阅读说明：本技术 一种连续式真空烧结炉 (Continuous vacuum sintering furnace ) 是由 王月富 高建星 程一军 陈晓旭 孔鹏 董永安 于 2021-08-11 设计创作，主要内容包括：本发明涉及烧结炉,具体为一种连续式真空烧结炉。包括依次连接的多个单体烧结炉和烧结产品传送机构；相邻单体烧结炉之间及两侧单体烧结炉的一端,密封连接有插板阀；单体烧结炉包括炉壳和加热室；烧结产品传送机构包括多个传送辊,单体烧结炉内的传送辊在炉壳内位于加热室的下方,加热室底部沿单体烧结炉的轴线方向开有与加热室等长的通槽；烧结产品传送机构还包括位于加热室内且由耐高温材料制成的托盘,托盘底部垂直固定有耐高温材料制成的支撑腿,支撑腿的一端与托盘底部固定、另一端穿过通槽而伸出加热室并与支撑板固定,支撑板位于传送辊上。本发明传送辊无需耐高温材料制成,也无需耐高温轴承,大大降低制造成本。(The invention relates to a sintering furnace, in particular to a continuous vacuum sintering furnace. Comprises a plurality of single sintering furnaces and a sintered product conveying mechanism which are connected in sequence; gate valves are hermetically connected between the adjacent monomer sintering furnaces and at one end of the monomer sintering furnaces on two sides; the single sintering furnace comprises a furnace shell and a heating chamber; the sintered product conveying mechanism comprises a plurality of conveying rollers, the conveying rollers in the single sintering furnace are positioned below the heating chamber in the furnace shell, and the bottom of the heating chamber is provided with through grooves with the same length as the heating chamber along the axial direction of the single sintering furnace; the sintered product conveying mechanism further comprises a tray which is located in the heating chamber and made of high-temperature-resistant materials, supporting legs made of the high-temperature-resistant materials are vertically fixed to the bottom of the tray, one end of each supporting leg is fixed to the bottom of the tray, the other end of each supporting leg penetrates through the through groove to extend out of the heating chamber and is fixed to the supporting plate, and the supporting plate is located on the conveying roller. The conveying roller is not required to be made of high-temperature-resistant materials, and is also not required to be made of high-temperature-resistant bearings, so that the manufacturing cost is greatly reduced.)

1. A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces (1) and a sintered product conveying mechanism which are connected in sequence; a gate valve (2) is hermetically connected between the adjacent monomer sintering furnaces (1) and at one end of each of the monomer sintering furnaces on the two sides; the single sintering furnace comprises a furnace shell (1.1) and a heating chamber (1.2) positioned in the furnace shell; the sintered product conveying mechanism comprises a plurality of conveying rollers (3) which are parallel to each other and vertical to the conveying direction, the conveying rollers (3) are respectively supported in each single sintering furnace (1) and each gate valve (2), the axes of the conveying rollers (3) are on the same horizontal plane, and the conveying rollers (3) are linked through gear transmission or chain wheel chain transmission in the furnace shell (1.1) and the gate valve (2); the device is characterized in that a conveying roller (3) in the single sintering furnace (1) is positioned below a heating chamber (1.2) in a furnace shell (1.1), and the bottom of the heating chamber (1.2) is provided with a through groove (1.2.1) with the same length as the heating chamber along the axial direction of the single sintering furnace; sintered product transport mechanism is still including being located heating chamber (1.2) and tray (4) of being made by high temperature resistant material, tray (4) bottom vertical fixation has supporting leg (5) that high temperature resistant material made, the one end of supporting leg (5) is fixed bottom tray (4), the other end passes logical groove (1.2.1) and stretches out heating chamber (1.2) and fixed with backup pad (6), backup pad (6) are located transfer roller (3).

2. The continuous vacuum sintering furnace according to claim 1, characterized in that the single sintering furnace at the leftmost side is used as a dewaxing furnace, the furnace shell (1.1) of the dewaxing furnace is provided with a water cooling structure, and a partition plate (1.3) is arranged between the furnace shell (1.1) and the heating chamber (1.2); the dewaxing furnace is provided with an inflation pipe (13) communicated with the heating chamber (1.2), the heating chamber (1.2) of the dewaxing furnace is internally provided with a horizontal inflation pipe (14) communicated with the inflation pipe (13), and the horizontal inflation pipe (14) is positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber.

3. A continuous vacuum sintering furnace as claimed in claim 1 or 2, characterized in that three-phase ac power is selected, each single sintering furnace is associated with a three-phase step-down transformer, the secondary side of the three-phase step-down transformer is connected in parallel with three rectifiers, and the three rectifiers respectively provide dc power for three temperature zones of the single sintering furnace.

4. A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces (1) and a sintered product conveying mechanism which are connected in sequence; one end of each of the monomer sintering furnaces (1) on the two sides is hermetically connected with a gate valve (2), a heat insulation gate valve (7) is hermetically connected between every two adjacent monomer sintering furnaces (1), or the heat insulation gate valves (7) are hermetically connected between every two adjacent monomer sintering furnaces, and the gate valves (2) are hermetically connected between every two adjacent monomer sintering furnaces; the single sintering furnace (1) comprises a furnace shell (1.1) and a heating chamber (1.2) positioned in the furnace shell (1.1); the sintered product conveying mechanism comprises a plurality of conveying rollers (3) which are parallel to each other and vertical to the conveying direction, the plurality of conveying rollers (3) are respectively supported in each single sintering furnace (1), each gate valve (2) and each heat insulation gate valve (7), the axes of the plurality of conveying rollers (3) are on the same horizontal plane, and the conveying rollers (3) are linked through gear transmission or chain wheel and chain transmission in the furnace shell (1.1), the gate valves (2) and the heat insulation gate valves (7); the device is characterized in that a conveying roller (3) in the single sintering furnace (1) is positioned below a heating chamber (1.2) in a furnace shell (1.1), and the bottom of the heating chamber (1.2) is provided with a through groove (1.2.1) with the same length as the heating chamber along the axial direction of the single sintering furnace (1); the sintered product conveying mechanism further comprises a tray (4) which is positioned in the heating chamber (1.2) and made of high-temperature-resistant materials, supporting legs (5) made of the high-temperature-resistant materials are vertically fixed at the bottom of the tray (4), one ends of the supporting legs (5) are fixed with the bottom of the tray (4), the other ends of the supporting legs penetrate through the through grooves (1.2.1) to extend out of the heating chamber (1.2) and are fixed with a supporting plate (6), and the supporting plate (6) is positioned on the conveying roller (3); the heat insulation gate valve (7) comprises a valve body (7.1), an air cylinder (7.2) and a heat insulation gate (7.3), the two ends of the valve body (7.1) are hermetically connected with the furnace shells (1.1) of the monomer sintering furnaces (1) on the two sides, the cylinder body of the air cylinder (7.2) is positioned outside the valve body (7.1) and fixed with the valve body (7.1), the piston rod of the air cylinder (7.2) extends into the valve body (7.1), and the heat insulation gate (7.3) is positioned in the valve body (7.1) and connected with the piston rod of the air cylinder (7.2).

5. A continuous vacuum sintering furnace according to claim 4, characterized in that the single sintering furnace at the leftmost side is used as a dewaxing furnace, the furnace shell (1.1) of the dewaxing furnace is provided with a water cooling structure, and a partition plate (1.3) is arranged between the furnace shell (1.1) and the heating chamber (1.2); the dewaxing furnace is provided with an inflation pipe (13) communicated with the heating chamber (1.2), the heating chamber (1.2) of the dewaxing furnace is internally provided with a horizontal inflation pipe (14) communicated with the inflation pipe (13), and the horizontal inflation pipe (14) is positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber.

6. A continuous vacuum sintering furnace according to claim 4 or 5, characterized in that the number of the single sintering furnaces (1) is four; the left side of the continuous vacuum sintering furnace is hermetically connected with a preparation chamber (8) through a gate valve (2), and the other end of the preparation chamber (8) is also hermetically connected with the gate valve (2); the preparation chamber (8) is different from the single sintering furnace (1) in that the preparation chamber (8) is not provided with a heating chamber (1) - (2) and a heating device; the right side of the continuous vacuum sintering furnace is also sequentially connected with a front cooling chamber (9), two aging furnaces (10) and a rear cooling chamber (11); a cooling fan and a heat exchanger are arranged on the front cooling chamber (9) and the rear cooling chamber (11); the aging furnace (10) and the monomer sintering furnace (1) have the same structure; the other ends of the monomer sintering furnace (1) at the rightmost side and the front cooling chamber (9), the front cooling chamber (9) and the aging furnace (10), the aging furnace (10) and the rear cooling chamber (11) are hermetically connected with gate valves (2); a simple heat insulation gate valve (7) is hermetically connected between the two aging furnaces (10); the sintered product conveying mechanism penetrates through the preparation chamber (8), the single sintering furnaces (1), the front cooling chamber (9), the aging furnaces (10), the rear cooling chamber (11), the gate valves (2) and the simple heat-insulating gate valves (7); the method is characterized in that a three-phase alternating-current power supply is selected, four single sintering furnaces and two aging furnaces respectively correspond to a three-phase step-down transformer, three rectifiers are connected in parallel on the secondary side of the three-phase step-down transformer, and the three rectifiers respectively provide direct-current power supply for three temperature areas of the single sintering furnaces or the aging furnaces.

7. A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces (1) and a sintered product conveying mechanism which are connected in sequence; one end of each single sintering furnace (1) at two sides is hermetically connected with a gate valve (2), and adjacent single sintering furnaces (1) are directly hermetically connected; the single sintering furnace (1) comprises a furnace shell (1.1) and a heating chamber (1.2) positioned in the furnace shell (1.1); the sintered product conveying mechanism comprises a plurality of conveying rollers (3) which are parallel to each other and vertical to the conveying direction, the conveying rollers (3) are respectively supported in each single sintering furnace (1) and the gate valve (2), the axes of the conveying rollers (3) are on the same horizontal plane, and the conveying rollers (3) are linked through gear transmission or chain wheel and chain transmission in the furnace shell (1.1) and the gate valve (2); the device is characterized in that a conveying roller (3) in the single sintering furnace (1) is positioned below a heating chamber (1.2) in a furnace shell (1.1), and the bottom of the heating chamber (1.2) is provided with a through groove (1.2.1) with the same length as the heating chamber (1.2) along the axial direction of the single sintering furnace (1); the sintered product conveying mechanism further comprises a tray (4) which is positioned in the heating chamber (1.2) and made of high-temperature-resistant materials, supporting legs (5) made of the high-temperature-resistant materials are vertically fixed at the bottom of the tray (4), one ends of the supporting legs (5) are fixed with the bottom of the tray (4), the other ends of the supporting legs penetrate through the through grooves (1.2.1) to extend out of the heating chamber (1.2) and are fixed with a supporting plate (6), and the supporting plate (6) is positioned on the conveying roller (3); one end of the tray (4) far away from the inlet of the single sintering furnace (1) is provided with a plug plate (12) vertical to the tray (4), and after the tray (4) completely enters the single sintering furnace (1), the plug plate (12) is just positioned between the adjacent single sintering furnaces (1) to play a role of a heat insulation plate.

8. The continuous vacuum sintering furnace according to claim 7, characterized in that the single sintering furnace at the leftmost side is used as a dewaxing furnace, the furnace shell (1.1) of the dewaxing furnace is provided with a water cooling structure, and a partition plate (1.3) is arranged between the furnace shell (1.1) and the heating chamber (1.2); the dewaxing furnace is provided with an inflation pipe (13) communicated with the heating chamber (1.2), the heating chamber (1.2) of the dewaxing furnace is internally provided with a horizontal inflation pipe (14) communicated with the inflation pipe (13), and the horizontal inflation pipe (14) is positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber.

9. A continuous vacuum sintering furnace according to claim 7 or 8, characterized in that the number of the single sintering furnaces (1) is four; the left side of the continuous vacuum sintering furnace is hermetically connected with a preparation chamber (8) through a gate valve (2), and the other end of the preparation chamber (8) is also hermetically connected with the gate valve (2); compared with the single sintering furnace (1), the preparation chamber (8) is characterized in that the preparation chamber (8) is not provided with a heating chamber (1.2) and a heating device; the right side of the continuous vacuum sintering furnace is also sequentially connected with a front cooling chamber (9), two aging furnaces (10) and a rear cooling chamber (11); a cooling fan and a heat exchanger are arranged on the front cooling chamber (9) and the rear cooling chamber (11); the aging furnace (10) and the monomer sintering furnace (1) have the same structure; the other ends of the monomer sintering furnace (1) at the rightmost side and the front cooling chamber (9), the front cooling chamber (9) and the aging furnace (10), the aging furnace (10) and the rear cooling chamber (11) are hermetically connected with gate valves (2); the two aging furnaces (10) are directly connected in a sealing way; the sintered product conveying mechanism penetrates through the preparation chamber (8), the single sintering furnaces (1), the front cooling chamber (9), the aging furnaces (10), the rear cooling chamber (11) and the gate valves (2); the method is characterized in that a three-phase alternating-current power supply is selected, four single sintering furnaces and two aging furnaces respectively correspond to a three-phase step-down transformer, three rectifiers are connected in parallel on the secondary side of the three-phase step-down transformer, and the three rectifiers respectively provide direct-current power supply for three temperature areas of the single sintering furnaces or the aging furnaces.

10. The continuous vacuum sintering furnace according to claim 9, wherein the vacuum pump independent from each single sintering furnace is eliminated, only the preparation chamber and the cooling chamber have independent vacuum pumps, and the single sintering furnaces and the aging furnaces have only one vacuum pump disposed at the furnace inlet end.

Technical Field

The invention relates to a sintering furnace, in particular to a continuous vacuum sintering furnace which is mainly used for sintering rare earth permanent magnets, titanium alloys and various MIMs and heat treatment of metal pieces.

Background

The continuous vacuum sintering furnace comprises a plurality of single sintering furnaces which are connected in sequence; determining the number of the single sintering furnaces according to different sintering products and sintering processes; one end of each monomer sintering furnace is connected with one end of each monomer sintering furnace through a gate valve; the continuous vacuum sintering furnace also comprises a conveying mechanism for sintering products, the conveying mechanism penetrates through each single sintering furnace and each gate valve, the sintering products are positioned on the conveying mechanism, the gate valves are opened, the sintering products are conveyed by the conveying mechanism to be transferred in the single sintering furnaces and between the adjacent single sintering furnaces, and the gate valves are closed after the transfer is finished. The single sintering furnace comprises a furnace shell and a heating chamber positioned in the furnace shell, wherein the inner wall of the heating chamber is provided with a heat preservation layer and heating parts which are uniformly distributed. Transport mechanism include a plurality of transfer rollers that are parallel to each other and perpendicular to direction of transfer, a plurality of transfer rollers support respectively in each monomer fritting furnace and each push-pull valve (also have a transfer roller in the push-pull valve usually), the axis of a plurality of transfer rollers is on same horizontal plane, in order to be located the sprocket chain transmission each other of stove outer covering and push-pull valve between each transfer roller, the lower part in the heating chamber is passed in the stove outer covering to the transfer roller in the monomer fritting furnace, a tray is placed on the sintered product is arranged in on the transfer roller or on the transfer roller, the sintered product is arranged in on the tray, the motor drives all transfer rollers rotation through gear or sprocket chain transmission, and realize the transfer of sintered product in the monomer fritting furnace and between the adjacent monomer fritting furnace.

The existing continuous vacuum sintering furnace has the following defects:

1) because the middle part of the conveying roller is positioned in the heating chamber, the conveying roller is made of high-temperature resistant materials (such as C-C composite materials), and a bearing for supporting the conveying roller is also a high-temperature resistant bearing; the conveying roller and the bearing thereof have larger consumption, so that the manufacturing cost of the existing continuous vacuum sintering furnace is high.

2) The heating chambers are separated by water-cooled gate valves, and cooling water takes away a large amount of heat, so that not only is energy consumption increased, but also the temperatures of two ends of a sintering area are low, and the uniformity of products is influenced.

3) In the existing continuous vacuum sintering furnace with three-phase alternating current power supply, each single sintering furnace adopts three single-phase transformers to respectively supply power for three temperature zones of the single sintering furnace, and the three single-phase transformers respectively correspond to one phase of three-phase alternating current, so that the quantity of the used transformers is large, the quantity of the temperature zones is limited, the power factor is low, and the quality of a power grid is influenced by three-phase imbalance caused by inconsistent power required by each temperature zone.

4) In order to improve the temperature of the two end surfaces, the existing sintering furnace adopts three sections of temperature control, namely a left section, a middle section and a right section, neglects the temperature difference between the upper part and the lower part, particularly the lower part, because the supporting materials are all heat conducting materials and no way of heat insulation is available, the lower part temperature is low, and the uniformity of a sintered product is reduced. The process has to be worked around to increase the temperature bandwidth of the process. But at a cost price.

Taking the sintered rare earth permanent magnet as an example, the number of the single sintering furnaces can be four; according to the preparation process of the sintered rare earth permanent magnet, the left side of the continuous vacuum sintering furnace is hermetically connected with a preparation chamber through a gate valve, and the other end of the preparation chamber is also hermetically connected with the gate valve; the preparation chamber is different from the single sintering furnace in that the preparation chamber is not provided with a heating device. The right side of the continuous vacuum sintering furnace is also sequentially connected with a front cooling chamber, two aging (treatment) furnaces and a rear cooling chamber; the front cooling chamber and the rear cooling chamber are provided with cooling fans and heat exchangers; the aging (treatment) furnace has the same structure as the single sintering furnace (the difference is that the temperature of the aging treatment is different from the sintering temperature); and gate valves are hermetically connected between the monomer sintering furnace at the rightmost side and the front cooling chamber, between the front cooling chamber and the aging furnace, between the two aging furnaces, between the aging furnace and the rear cooling chamber and at the other end of the rear cooling chamber. The conveying mechanism penetrates through the preparation chamber, the single sintering furnaces, the front cooling chamber, the aging furnaces, the rear cooling chamber and the gate valves.

Disclosure of Invention

The invention solves the defects of the existing continuous vacuum sintering furnace and provides an improved continuous vacuum sintering furnace.

The invention is realized by adopting the following technical scheme: a continuous vacuum sintering furnace comprises a plurality of single sintering furnaces and a sintered product conveying mechanism which are connected in sequence; gate valves are hermetically connected between the adjacent monomer sintering furnaces and at one end of the monomer sintering furnaces on two sides; the single sintering furnace comprises a furnace shell and a heating chamber positioned in the furnace shell; the sintered product conveying mechanism comprises a plurality of conveying rollers which are parallel to each other and vertical to the conveying direction, the conveying rollers are respectively supported in each single sintering furnace and each gate valve, the axes of the conveying rollers are on the same horizontal plane, and the conveying rollers are linked through gear transmission or chain wheel and chain transmission in the furnace shell and the gate valve; a conveying roller in the single sintering furnace is positioned below the heating chamber in the furnace shell, and the bottom of the heating chamber is provided with a through groove which is as long as the heating chamber (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace (namely the conveying direction of the sintered product conveying mechanism); the sintered product conveying mechanism further comprises a tray which is located in the heating chamber and made of high-temperature-resistant materials, supporting legs made of the high-temperature-resistant materials are vertically fixed to the bottom of the tray, one end of each supporting leg is fixed to the bottom of the tray, the other end of each supporting leg penetrates through the through groove to extend out of the heating chamber and is fixed to the supporting plate, and the supporting plate is located on the conveying roller. When the sintering device works, the sintered products are placed on the tray, and the motor drives all the conveying rollers to rotate through the transmission of the gears or the chain wheels and the chains, so that the sintered products are transferred in the monomer sintering furnaces and between the adjacent monomer sintering furnaces. According to the invention, through the through groove formed in the bottom of the heating chamber and the supporting legs are additionally arranged, the conveying roller is moved out of the heating chamber, the conveying roller is not required to be made of high-temperature-resistant materials, the consumption of the high-temperature-resistant materials of the sintered product conveying mechanism is greatly reduced, and a high-temperature-resistant bearing is not required, so that the manufacturing cost is greatly reduced.

The other technical scheme of the invention is as follows: a continuous vacuum sintering furnace comprises a plurality of single sintering furnaces and a sintered product conveying mechanism which are connected in sequence; one end of each of the monomer sintering furnaces on the two sides is hermetically connected with a gate valve, and a heat insulation gate valve is hermetically connected between every two adjacent monomer sintering furnaces, or a heat insulation gate valve is hermetically connected between every two adjacent monomer sintering furnaces, and a gate valve is hermetically connected between every two adjacent monomer sintering furnaces; the single sintering furnace comprises a furnace shell and a heating chamber positioned in the furnace shell; the sintered product conveying mechanism comprises a plurality of conveying rollers which are parallel to each other and vertical to the conveying direction, the conveying rollers are respectively supported in each single sintering furnace, each gate valve and each heat insulation gate valve, the axes of the conveying rollers are on the same horizontal plane, and the conveying rollers are linked through gear transmission or chain wheel and chain transmission in the furnace shell, the gate valves and the heat insulation gate valves; a conveying roller in the single sintering furnace is positioned below the heating chamber in the furnace shell, and the bottom of the heating chamber is provided with a through groove which is as long as the heating chamber (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace (namely the conveying direction of the sintered product conveying mechanism); the sintered product conveying mechanism also comprises a tray which is positioned in the heating chamber and is made of high-temperature resistant materials, supporting legs made of the high-temperature resistant materials are vertically fixed at the bottom of the tray, one end of each supporting leg is fixed with the bottom of the tray, the other end of each supporting leg penetrates through the through groove to extend out of the heating chamber and is fixed with a supporting plate, and the supporting plate is positioned on the conveying roller; the heat insulation gate valve comprises a valve body, a cylinder and heat insulation gate inserts, wherein two ends of the valve body are hermetically connected with furnace shells of the monomer sintering furnaces on two sides, a cylinder body of the cylinder is positioned outside the valve body and fixed with the valve body, a piston rod of the cylinder extends into the valve body, and the heat insulation gate inserts are positioned in the valve body and connected with the piston rod of the cylinder. When the heat-insulating flashboard works, the heat-insulating flashboard can move up and down under the driving of the cylinder, so that the opening and closing of the heat-insulating flashboard valve are realized. The technical scheme also has the technical effect of reducing the manufacturing cost of the technical scheme. The heat insulation flashboard valve isolates heat radiation between adjacent monomer sintering furnaces, and the heat insulation flashboard and the ports of heating chambers of the monomer sintering furnaces on two sides are not strictly sealed, so that gas between the adjacent monomer sintering furnaces cannot be strictly isolated, but because the pressure of the adjacent monomer sintering furnaces is the same or close to that of the adjacent monomer sintering furnaces, a large amount of gas exchange between the adjacent monomer sintering furnaces is avoided under the isolation of the heat insulation board, and the operation of the continuous vacuum sintering furnace and the realization of a normal sintering process are not influenced; but the structure of the heat insulation gate valve is greatly simplified and the cost is reduced compared with the traditional gate valve, more importantly, no cooling water is used for carrying away a large amount of heat, the energy is saved, the temperature uniformity of a heating chamber is improved, and the function of further reducing the manufacturing cost of the continuous vacuum sintering furnace is achieved.

The invention also discloses a technical scheme: a continuous vacuum sintering furnace comprises a plurality of single sintering furnaces and a sintered product conveying mechanism which are connected in sequence; one end of each single sintering furnace on two sides is hermetically connected with a gate valve, and adjacent single sintering furnaces are directly hermetically connected; the single sintering furnace comprises a furnace shell and a heating chamber positioned in the furnace shell; the sintered product conveying mechanism comprises a plurality of conveying rollers which are parallel to each other and vertical to the conveying direction, the conveying rollers are respectively supported in each single sintering furnace and the gate valve, the axes of the conveying rollers are on the same horizontal plane, and the conveying rollers are linked through gear transmission or chain wheel and chain transmission in the furnace shell and the gate valve; a conveying roller in the single sintering furnace is positioned below the heating chamber in the furnace shell, and the bottom of the heating chamber is provided with a through groove which is as long as the heating chamber (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace (namely the conveying direction of the sintered product conveying mechanism); the sintered product conveying mechanism also comprises a tray which is positioned in the heating chamber and is made of high-temperature resistant materials, supporting legs made of the high-temperature resistant materials are vertically fixed at the bottom of the tray, one end of each supporting leg is fixed with the bottom of the tray, the other end of each supporting leg penetrates through the through groove to extend out of the heating chamber and is fixed with a supporting plate, and the supporting plate is positioned on the conveying roller; the tray is provided with a plug plate perpendicular to the tray at one end far away from the entrance of the monomer sintering furnace, and after the tray completely enters the monomer sintering furnace, the plug plate is just positioned between adjacent monomer sintering furnaces to play a role of a heat insulation plate. Because the plug and the heating chamber access passage have certain clearance, the technical proposal is used when the sintering process has no large amount of gas release, or the released gas is not polluting gas, and when the adjacent monomer sintering furnaces have no pressure difference, such as vacuum heat treatment, has no gas release at all. On the basis of the technical effects of reducing the manufacturing cost of the two technical schemes, compared with the two technical schemes, the technical scheme removes a gate valve or a heat insulation gate valve between the adjacent monomer sintering furnaces, and takes the plug plate at the end part of the tray as a heat insulation plate between the adjacent monomer sintering furnaces, so that the structure is simplified, and the cost is further reduced; meanwhile, the heat dissipation is less, the temperature is uniform, and the energy is saved.

Drawings

FIG. 1 is a schematic structural view of a continuous vacuum sintering furnace according to an embodiment 2 of the present invention;

FIG. 2 is an enlarged view of the structure of the single sintering furnace of FIG. 1;

FIG. 3 is an enlarged view of the structure of the cooling furnace of FIG. 1;

FIG. 4 is a schematic longitudinal sectional view of the single sintering furnace of FIG. 1;

FIG. 5 is an enlarged view of a portion of the structure of FIG. 4;

FIG. 6 is an enlarged view of the simple thermal insulation gate valve shown in FIG. 1;

FIG. 7 is a schematic structural view of an embodiment 3 of the continuous vacuum sintering furnace according to the present invention;

FIG. 8 is an enlarged view of the structure of the single sintering furnace of FIG. 7;

FIG. 9 is a schematic view of the structure of the tray with the blanking panels of FIG. 8;

FIG. 10 is a schematic diagram of a power supply circuit of a single sintering furnace (or an extended aging furnace) of the continuous vacuum sintering furnace according to the present invention;

FIG. 11 is a schematic diagram showing the distribution of heating means in the single-body sintering furnace;

FIG. 12 is a sectional view of the leftmost single sintering furnace (dewaxing furnace) of the continuous vacuum sintering furnace according to the present invention;

fig. 13 is a graph of sintering temperature.

In the figure: 1-monomer sintering furnace, 1.1-furnace shell, 1.2-heating chamber, 1.2.1-through groove, 1.3-isolation plate, 2-gate valve, 3-conveying roller, 3.1-rotating shaft, 3.2-roller, 3.3-chain wheel, 4-tray, 5-supporting leg, 6-supporting plate, 7-simple heat-insulating gate valve, 7.1-valve body, 7.2-cylinder, 7.3-heat-insulating plug board, 8-preparation chamber, 9-front cooling chamber, 10-aging furnace, 11-rear cooling chamber, 12-plug plate, 13-inflation pipe and 14-inflation transverse pipe.

Detailed Description

Example 1

A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces 1 and a sintered product conveying mechanism which are connected in sequence; gate valves 2 are hermetically connected between the adjacent monomer sintering furnaces 1 and at one end of the monomer sintering furnaces on two sides; the single sintering furnace comprises a furnace shell 1.1 and a heating chamber 1.2 positioned in the furnace shell; the sintered product conveying mechanism comprises a plurality of conveying rollers 3 which are parallel to each other and vertical to the conveying direction, the plurality of conveying rollers 3 are respectively supported in each single sintering furnace 1 and each gate valve 2, the axes of the plurality of conveying rollers 3 are on the same horizontal plane, and the conveying rollers 3 are linked through gear transmission or chain wheel and chain transmission in the furnace shell 1.1 and the gate valve 2; a conveying roller 3 in the single sintering furnace 1 is positioned below a heating chamber 1.2 in a furnace shell 1.1, and the bottom of the heating chamber 1.2 is provided with a through groove 1.2.1 which is as long as the heating chamber (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace (namely the conveying direction of a sintered product conveying mechanism); the sintered product conveying mechanism further comprises a tray 4 which is located in the heating chamber 1.2 and is made of high-temperature-resistant materials, supporting legs 5 made of the high-temperature-resistant materials are vertically fixed at the bottom of the tray 4, one end of each supporting leg 5 is fixed to the bottom of the tray 4, the other end of each supporting leg penetrates through the through groove 1.2.1 to extend out of the heating chamber 1.2 and is fixed with the supporting plate 6, and the supporting plate 6 is located on the conveying roller 3.

The single sintering furnace at the leftmost side is used as a dewaxing furnace, a furnace shell 1.1 of the dewaxing furnace is provided with a water cooling structure, and an isolation plate 1.3 is arranged between the furnace shell 1.1 and a heating chamber 1.2; the dewaxing furnace is provided with an inflation pipe 13 which leads into the heating chamber 1.2, the heating chamber 1.2 of the dewaxing furnace is internally provided with an inflation transverse pipe 14 which is communicated with the inflation pipe 13, and the inflation transverse pipes 14 are positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber (as shown in figure 12). The partition plate 1.3 can prevent high-temperature organic steam formed by dewaxing from directly contacting with the inner wall of the furnace shell of the water-cooled dewaxing furnace, so that condensed liquid formed by the high-temperature organic steam on the inner wall of the furnace shell is prevented; argon is filled into the heating chamber through the gas filling pipe 13 and the gas filling transverse pipe 14, so that the extraction rate of the organic steam formed by dewaxing is improved.

The continuous vacuum sintering furnace selects a three-phase alternating current power supply, each single sintering furnace corresponds to a three-phase step-down transformer, the secondary side of each three-phase step-down transformer is connected with three rectifiers in parallel, and the three rectifiers respectively provide direct current power supply for three temperature areas of the single sintering furnaces. Thus, each temperature zone of the single sintering furnace 1 is provided with independent three-phase rectification, and power supply of the sintering furnace without alternating current waveform distortion and with high power factor is realized; the method is not limited by the number of temperature zones, and is easy to realize for non-three zones (only by connecting rectifiers in parallel); only one transformer is needed for each single sintering furnace, so that the cost is reduced and the circuit is simplified. The three temperature zones are distributed from top to bottom, the middle temperature zone is divided into a middle left temperature zone and a middle right temperature zone, and heating devices of the middle left temperature zone and the middle right temperature zone are mutually connected in parallel (shown in figure 11). Thus, the temperature uniformity of the heating chamber, particularly the bottom of the heating chamber, can be improved.

During specific implementation, the number of the through grooves 1.2.1 at the bottom of the heating chamber 1.2 is two, correspondingly, the number of the supporting legs 5 at the bottom of the tray 4 is two, each row is three, the lower ends of the supporting legs 5 in each row are respectively fixed with a supporting plate 6, and the supporting plates 6 are positioned on the conveying rollers 3. The conveying roller 3 consists of a supported rotating shaft 3.1 and rollers 3.2 fixed on the rotating shaft 3.1, and the number of the rollers 3.2 is consistent with that of the through grooves 1.2.1; a chain wheel 3.3 is fixed on the rotating shaft 3.1. The whole continuous vacuum sintering furnace can be only provided with one motor, all the conveying rollers 3 are driven by a transmission mechanism, and each single sintering furnace 1 can also be provided with one motor to drive the conveying rollers 3 in the single sintering furnace and adjacent gate valves. The upper end of the supporting leg 5 is directly fastened on the tray 4 by threads, and the supporting leg 5 and the tray 4 are both made of C-C composite materials. The space between the adjacent supporting legs 5 is filled with hard carbon felt.

Example 2

A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces 1 and a sintered product conveying mechanism which are connected in sequence; one end of each of the monomer sintering furnaces 1 on the two sides is hermetically connected with a gate valve 2, a simple heat insulation gate valve 7 is hermetically connected between every two adjacent monomer sintering furnaces 1, or a heat insulation gate valve 7 is hermetically connected between every two adjacent monomer sintering furnaces, and a gate valve 2 is hermetically connected between every two adjacent monomer sintering furnaces; the single sintering furnace 1 comprises a furnace shell 1.1 and a heating chamber 1.2 positioned in the furnace shell 1.1; the sintered product conveying mechanism comprises a plurality of conveying rollers 3 which are parallel to each other and vertical to the conveying direction, the plurality of conveying rollers 3 are respectively supported in each single sintering furnace 1, each gate valve 2 and each simple heat insulation gate valve 7, the axes of the plurality of conveying rollers 3 are on the same horizontal plane, and the conveying rollers 3 are linked through gear transmission or chain wheel and chain transmission in the furnace shell 1.1, the gate valves 2 and the simple heat insulation gate valves 7; a conveying roller 3 in the single sintering furnace 1 is positioned below a heating chamber 1.2 in a furnace shell 1.1, and the bottom of the heating chamber 1.2 is provided with a through groove 1.2.1 which is as long as the heating chamber (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace 1 (namely the conveying direction of a sintered product conveying mechanism); the sintered product conveying mechanism also comprises a tray 4 which is positioned in the heating chamber 1.2 and is made of high-temperature resistant materials, supporting legs 5 made of high-temperature resistant materials are vertically fixed at the bottom of the tray 4, one end of each supporting leg 5 is fixed with the bottom of the tray 4, the other end of each supporting leg 5 penetrates through the through groove 1.2.1 to extend out of the heating chamber 1.2 and is fixed with a supporting plate 6, and the supporting plate 6 is positioned on the conveying roller 3; the simple heat insulation gate valve 7 comprises a valve body 7.1, a cylinder 7.2 and a heat insulation gate 7.3, the two ends of the valve body 7.1 are hermetically connected with the furnace shells 1.1 of the monomer sintering furnaces 1 on the two sides, the cylinder body of the cylinder 7.2 is positioned outside the valve body 7.1 and fixed with the valve body 7.1, the piston rod of the cylinder 7.2 extends into the valve body 7.1, and the heat insulation gate 7.3 is positioned in the valve body 7.1 and connected with the piston rod of the cylinder 7.2. Furthermore, a vacuum pump communicated with the inner cavity of the valve body 7.1 is fixed on the valve body 7.1 of the simple heat insulation gate valve 7, and the vacuum pump simultaneously vacuumizes the monomer sintering furnaces 1 on the two sides of the simple heat insulation gate valve 7, so that the gas pressure of the adjacent monomer sintering furnaces 1 is balanced, and compared with the situation that the adjacent monomer sintering furnaces are respectively provided with the vacuum pump, one vacuum pump is saved, and the cost is further reduced.

The single sintering furnace at the leftmost side is used as a dewaxing furnace, a furnace shell 1.1 of the dewaxing furnace is provided with a water cooling structure, and an isolation plate 1.3 is arranged between the furnace shell 1.1 and a heating chamber 1.2; the dewaxing furnace is provided with an inflation pipe 13 which leads into the heating chamber 1.2, the heating chamber 1.2 of the dewaxing furnace is internally provided with an inflation transverse pipe 14 which is communicated with the inflation pipe 13, and the inflation transverse pipes 14 are positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber (as shown in figure 12). The partition plate 1.3 can prevent high-temperature organic steam formed by dewaxing from directly contacting with the inner wall of the furnace shell of the water-cooled dewaxing furnace, so that condensed liquid formed by the high-temperature organic steam on the inner wall of the furnace shell is prevented; argon is filled into the heating chamber through the gas filling pipe 13 and the gas filling transverse pipe 14, so that the extraction rate of the organic steam formed by dewaxing is improved.

Taking the sintered rare earth permanent magnet as an example, the number of the single sintering furnaces 1 can be four; according to the preparation process of the sintered rare earth permanent magnet, the left side of the continuous vacuum sintering furnace is hermetically connected with a preparation chamber 8 through a gate valve 2, and the other end of the preparation chamber 8 is also hermetically connected with the gate valve 2; the preparation chamber 8 is different from the single sintering furnace 1 in that the heating chamber 1.2 and the heating device are not provided in the preparation chamber 8. The right side of the continuous vacuum sintering furnace is also sequentially connected with a front cooling chamber 9, two aging (treatment) furnaces 10 and a rear cooling chamber 11; a cooling fan and a heat exchanger are arranged on the front cooling chamber 9 and the rear cooling chamber 11; the aging (treatment) furnace 10 has the same structure as the single sintering furnace 1 (except that the temperature of the aging treatment is different from the sintering temperature); the gate valves 2 are hermetically connected between the monomer sintering furnace 1 at the rightmost side and the front cooling chamber 9, between the front cooling chamber 9 and the aging furnace 10, between the aging furnace 10 and the rear cooling chamber 11 and at the other end of the rear cooling chamber 11; a simple heat insulation gate valve 7 is hermetically connected between the two aging furnaces 10; the sintered product conveying mechanism penetrates through the preparation chamber 8, the single sintering furnaces 1, the front cooling chamber 9, the aging furnaces 10, the rear cooling chamber 11, the gate valves 2 and the simple heat insulation gate valves 7.

The continuous vacuum sintering furnace adopts a three-phase alternating current power supply, the four single sintering furnaces and the two aging furnaces respectively correspond to a three-phase step-down transformer, the secondary side of the three-phase step-down transformer is connected with three rectifiers in parallel, and the three rectifiers respectively provide direct current power supply for three temperature areas of the single sintering furnaces or the aging furnaces (as shown in figure 10). Therefore, each temperature area of the single sintering furnace and the aging furnace is independent three-phase rectification, and power supply of the sintering furnace without alternating current waveform distortion and with high power factor is realized; the method is not limited by the number of temperature zones, and is easy to realize for non-three zones (only by connecting rectifiers in parallel); only one transformer is needed for each single sintering furnace or aging furnace, so that the cost is reduced and the circuit is simplified. The three temperature zones are distributed from top to bottom, the middle temperature zone is divided into a middle left temperature zone and a middle right temperature zone, and heating devices of the middle left temperature zone and the middle right temperature zone are mutually connected in parallel (shown in figure 11). Thus, the temperature uniformity of the heating chamber, particularly the bottom of the heating chamber, can be improved.

During specific implementation, the number of the through grooves 1.2.1 at the bottom of the heating chamber 1.2 is two, correspondingly, the number of the supporting legs 5 at the bottom of the tray 4 is two, each row is three, the lower ends of the supporting legs 5 in each row are respectively fixed with a supporting plate 6, and the supporting plates 6 are positioned on the conveying rollers 3. The conveying roller 3 consists of a supported rotating shaft 3.1 and rollers 3.2 fixed on the rotating shaft 3.1, and the number of the rollers 3.2 is consistent with that of the through grooves 1.2.1; a chain wheel 3.3 is fixed on the rotating shaft 3.1. The whole continuous vacuum sintering furnace can be only provided with one motor, all the conveying rollers 3 are driven by a transmission mechanism, and each single sintering furnace 1 can also be provided with one motor to drive the conveying rollers 3 in the single sintering furnace and adjacent gate valves. The upper end of the supporting leg 5 is directly fastened on the tray 4 by threads, and the supporting leg 5 and the tray 4 are both made of C-C composite materials. The space between the adjacent supporting legs 5 is filled with hard carbon felt.

Example 3

A continuous vacuum sintering furnace comprises a plurality of single sintering furnaces 1 and a sintered product conveying mechanism which are connected in sequence; one end of each single sintering furnace 1 on two sides is hermetically connected with a gate valve 2, and adjacent single sintering furnaces 1 are directly hermetically connected; the single sintering furnace 1 comprises a furnace shell 1.1 and a heating chamber 1.2 positioned in the furnace shell 1.1; the sintered product conveying mechanism comprises a plurality of conveying rollers 3 which are parallel to each other and vertical to the conveying direction, the plurality of conveying rollers 3 are respectively supported in each single sintering furnace 1 and the gate valve 2, the axes of the plurality of conveying rollers 3 are on the same horizontal plane, and the conveying rollers 3 are linked through gear transmission or chain wheel and chain transmission in the furnace shell 1.1 and the gate valve 2; a conveying roller 3 in the single sintering furnace 1 is positioned below a heating chamber 1.2 in a furnace shell 1.1, and the bottom of the heating chamber 1.2 is provided with a through groove 1.2.1 which is as long as the heating chamber 1.2 (the axial direction of the single sintering furnace is the length direction of the heating chamber) along the axial direction of the single sintering furnace 1 (namely the conveying direction of a sintered product conveying mechanism); the sintered product conveying mechanism also comprises a tray 4 which is positioned in the heating chamber 1.2 and is made of high-temperature resistant materials, supporting legs 5 made of high-temperature resistant materials are vertically fixed at the bottom of the tray 4, one end of each supporting leg 5 is fixed with the bottom of the tray 4, the other end of each supporting leg 5 penetrates through the through groove 1.2.1 to extend out of the heating chamber 1.2 and is fixed with a supporting plate 6, and the supporting plate 6 is positioned on the conveying roller 3; one end of the tray 4, which is far away from the inlet of the single sintering furnace 1, is provided with a plug plate 12 vertical to the tray 4, and after the tray 4 completely enters the single sintering furnace 1, the plug plate 12 is just positioned between the adjacent single sintering furnaces 1 to play a role of a heat insulation plate.

The single sintering furnace at the leftmost side is used as a dewaxing furnace, a furnace shell 1.1 of the dewaxing furnace is provided with a water cooling structure, and an isolation plate 1.3 is arranged between the furnace shell 1.1 and a heating chamber 1.2; the dewaxing furnace is provided with an inflation pipe 13 which leads into the heating chamber 1.2, the heating chamber 1.2 of the dewaxing furnace is internally provided with an inflation transverse pipe 14 which is communicated with the inflation pipe 13, and the inflation transverse pipes 14 are positioned at the top of the heating chamber and distributed along the axial direction of the heating chamber (as shown in figure 12). The partition plate 1.3 can prevent high-temperature organic steam formed by dewaxing from directly contacting with the inner wall of the furnace shell of the water-cooled dewaxing furnace, so that condensed liquid formed by the high-temperature organic steam on the inner wall of the furnace shell is prevented; argon is filled into the heating chamber through the gas filling pipe 13 and the gas filling transverse pipe 14, so that the extraction rate of the organic steam formed by dewaxing is improved.

Taking the sintered rare earth permanent magnet as an example, the number of the single sintering furnaces 1 can be four; according to the preparation process of the sintered rare earth permanent magnet, the left side of the continuous vacuum sintering furnace is hermetically connected with a preparation chamber 8 through a gate valve 2, and the other end of the preparation chamber 8 is also hermetically connected with the gate valve 2; the preparation chamber 8 is different from the single sintering furnace 1 in that the heating chamber 1.2 and the heating device are not provided in the preparation chamber 8. The right side of the continuous vacuum sintering furnace is also sequentially connected with a front cooling chamber 9, two aging (treatment) furnaces 10 and a rear cooling chamber 11; a cooling fan and a heat exchanger are arranged on the front cooling chamber 9 and the rear cooling chamber 11; the aging (treatment) furnace 10 has the same structure as the single sintering furnace 1 (except that the temperature of the aging treatment is different from the sintering temperature); the gate valves 2 are hermetically connected between the monomer sintering furnace 1 at the rightmost side and the front cooling chamber 9, between the front cooling chamber 9 and the aging furnace 10, between the aging furnace 10 and the rear cooling chamber 11 and at the other end of the rear cooling chamber 11; the two aging furnaces 10 are directly connected in a sealing way; the sintered product conveying mechanism penetrates through the preparation chamber 8, the single sintering furnaces 1, the front cooling chamber 9, the aging furnaces 10, the rear cooling chamber 11 and the gate valves 2. Meanwhile, the vacuum pump independent of each single sintering furnace can be removed, only the preparation chamber and the cooling chamber are provided with independent vacuum units, and the single sintering furnaces and the two aging furnaces are provided with only one vacuum pump and are arranged at the furnace inlet ends. The vacuum pump is saved.

The continuous vacuum sintering furnace adopts a three-phase alternating current power supply, the four single sintering furnaces and the two aging furnaces respectively correspond to a three-phase step-down transformer, the secondary side of the three-phase step-down transformer is connected with three rectifiers in parallel, and the three rectifiers respectively provide direct current power supply for three temperature areas of the single sintering furnaces or the aging furnaces (as shown in figure 10). Therefore, each temperature area of the single sintering furnace and the aging furnace is independent three-phase rectification, and power supply of the sintering furnace without alternating current waveform distortion and with high power factor is realized; the method is not limited by the number of temperature zones, and is easy to realize for non-three zones (only by connecting rectifiers in parallel); only one transformer is needed for each single sintering furnace or aging furnace, so that the cost is reduced and the circuit is simplified. The rectifier adopts zero-crossing triggering, duty ratio power regulation and power factor of 1. The three temperature zones are distributed from top to bottom, the middle temperature zone is divided into a middle left temperature zone and a middle right temperature zone, and heating devices of the middle left temperature zone and the middle right temperature zone are mutually connected in parallel (shown in figure 11). Thus, the temperature uniformity of the heating chamber, particularly the bottom of the heating chamber, can be improved.

During specific implementation, the number of the through grooves 1.2.1 at the bottom of the heating chamber 1.2 is two, correspondingly, the number of the supporting legs 5 at the bottom of the tray 4 is two, each row is three, the lower ends of the supporting legs 5 in each row are respectively fixed with a supporting plate 6, and the supporting plates 6 are positioned on the conveying rollers 3. The conveying roller 3 consists of a supported rotating shaft 3.1 and rollers 3.2 fixed on the rotating shaft 3.1, and the number of the rollers 3.2 is consistent with that of the through grooves 1.2.1; a chain wheel 3.3 is fixed on the rotating shaft 3.1. The whole continuous vacuum sintering furnace can be only provided with one motor, all the conveying rollers 3 are driven by a transmission mechanism, and each single sintering furnace 1 can also be provided with one motor to drive the conveying rollers 3 in the single sintering furnace and adjacent gate valves. The upper end of the supporting leg 5 is directly fastened on the tray 4 by threads, and the supporting leg 5 and the tray 4 are both made of C-C composite materials. The space between the adjacent supporting legs 5 is filled with hard carbon felt.

Continuous sintering process of NdFeB: and (3) placing the sintering material boxes (72) on the tray in order, opening the gate valve of the preparation chamber, and simultaneously starting the outer roller way motor and the roller way motor of the preparation chamber until the sintering material boxes reach a set position.

Starting the vacuum pump of the preparation chamber to reach the rated vacuum degree.

If the material is in a continuous working state, the material in the post-cooling chamber is conveyed out before the time of the beat conversion, and then the material is vacuumized and is ready to receive the cooling of the next batch.

Lifting all the gate valves, (except the gate valve outside the preparation chamber and the valve outside the after-cooling chamber) starting all the transmission motors until each tray moves to the next position. The transmission motors are independently controlled through the laser positioner.

At this point, the post-ageing oven is empty.

All of the gate valves are dropped to the closed position.

And filling argon into the two cooling chambers to a set pressure, and starting a fan for cooling.

And (3) when the temperature of the front cooling chamber reaches a set temperature, vacuumizing to a set value, opening the gate valve, starting the transmission motors of the front cooling chamber and the front aging chamber, and closing the gate valve after the transmission motors are in place.

And lifting a gate valve, starting a high-temperature aging chamber and a front cooling chamber transmission motor, and moving the sintering tray to the front cooling chamber. And (5) closing the gate valve and starting the cooling fan. After the set temperature was lowered, cooling was stopped. Starting the vacuum pump to set vacuum degree.

And lifting a gate valve, and reversely starting the transmission motors of the high-temperature aging furnace and the front cooling chamber to return the materials in the front cooling chamber to the high-temperature aging furnace. The temperature is raised to the aging temperature.

In order to fully utilize the time, the workpiece in the high-temperature aging furnace is continuously sintered according to the process while the front cooling chamber is cooled.

See the sintering curve shown in fig. 13 for details.

Sintering the titanium alloy MIM product. The production process is similar to NdFeB. The difference is that the dewaxing time is long and high temperature aging is not required. The method can be completed only by five chambers, namely a preparation chamber, a dewaxing chamber, a dehydrogenation chamber, a sintering chamber and a cooling chamber.