阅读说明：本技术 一种环向冷却与轴向冷却串联的主轴冷却结构及机床 (Main shaft cooling structure with annular cooling and axial cooling connected in series and machine tool ) 是由 林小亮 宋卫海 李曰阳 成小飞 刘鑫 于 2021-08-27 设计创作，主要内容包括：本发明公开了一种环向冷却与轴向冷却串联的主轴冷却结构及机床,主要包括主轴套；主轴套上的冷却回路由两部分串联组成：一是螺旋槽冷却管路；一是依次串联连接的轴向孔冷却管路,两部分管路串联连接组成循环式冷却回路。所述螺旋冷却槽处的冷却管路与所述若干轴向孔串联而成的冷却管路串联组成完整的冷却回路,使得进入所述冷却回路的冷却液呈循环式流动。(The invention discloses a main shaft cooling structure with annular cooling and axial cooling connected in series and a machine tool, which mainly comprise a main shaft sleeve; the cooling circuit on the main shaft sleeve is composed of two parts in series: firstly, a spiral groove cooling pipeline; firstly, the axial hole cooling pipeline is connected in series in sequence, and the two parts of pipelines are connected in series to form a circulating cooling loop. And a cooling pipeline at the spiral cooling groove is connected in series with a cooling pipeline formed by connecting the plurality of axial holes in series to form a complete cooling loop, so that cooling liquid entering the cooling loop flows in a circulating manner.)

1. A main shaft cooling structure with annular cooling and axial cooling in series connection is characterized by comprising a main shaft sleeve, a main shaft sleeve seat, a flange plate, an end face sealing ring and a radial sealing ring; the middle part of the main shaft sleeve is provided with a circle of bulges, one side of each bulge is connected with a main shaft sleeve seat sleeved on the main shaft sleeve, and two ends of the main shaft sleeve seat are sealed with the main shaft sleeve through radial sealing rings; the end face of the main shaft sleeve positioned on the other side of the bulge is connected with the flange plate, and the main shaft sleeve and the flange plate are sealed through an end face sealing ring; the two ends of the outer cylindrical surface of the spindle sleeve arranged in the spindle sleeve seat are provided with sealing ring grooves for mounting the radial sealing rings, a hoop cooling pipeline is arranged on the spindle sleeve section between the two sealing ring grooves, an axial hole cooling pipeline is arranged on the rest section of the spindle sleeve, one end of the axial hole cooling pipeline is connected with the hoop cooling pipeline in series to form a circulating cooling loop, and the other end of the axial hole cooling pipeline is communicated with the fan-shaped grooves on the flange plate.

2. The spindle cooling structure according to claim 1, wherein the circumferential cooling line includes a first annular groove, a plurality of spindle cover sector grooves, a middle annular groove, a spiral cooling groove, and a second annular groove, which are sequentially formed from a middle position of the spindle cover to one end of the spindle cover.

3. A spindle cooling arrangement as claimed in claim 2, wherein said first annular groove communicates with a coolant inlet located in the spindle sleeve; the second annular groove is communicated with a cooling liquid outlet positioned on the spindle sleeve seat.

4. The spindle cooling structure according to claim 2, wherein the spindle cover base fan-shaped groove is provided along a circumferential direction of the spindle cover.

5. The spindle cooling structure according to claim 2, wherein the axial bore cooling line includes a first axial bore, a second axial bore, and a third axial bore; the first axial hole is communicated with the first annular groove through a first radial hole; the second axial hole is communicated with the second annular groove through a second radial hole; the third axial hole and the third radial hole are communicated with the spindle sleeve seat sector groove.

6. The spindle cooling structure according to claim 2, wherein the number of the third axial holes, the third radial holes, and the spindle cover sector grooves is equal.

7. A spindle cooling structure as claimed in claim 5, wherein the first annular groove, the plurality of sector grooves, the intermediate annular groove, the spiral cooling groove, the second annular groove, the first axial hole, the second axial hole, the third axial hole and the flange sector grooves have the same diameter.

8. The spindle cooling structure according to claim 2, wherein a drain hole is further provided in the spindle hub, and the drain hole is located in a non-fitting section of the spindle hub and the spindle cover.

9. A machine tool comprising the spindle cooling structure according to any one of claims 1 to 8.

10. The machine tool of claim 9 further comprising a spindle, said spindle engaging the spindle sleeve through a bearing.

Technical Field

The invention relates to the technical field of machine tool spindle cooling, in particular to a spindle cooling structure and a machine tool, wherein the spindle nose end of the machine tool spindle is close to a workpiece to the maximum extent.

Background

With the rapid development of the manufacturing industry, the market has higher requirements on the performance of the numerical control machining center, the rotating speed of the main shaft is required to be high, the temperature rise of the main shaft is required to be small, and the machining precision of the numerical control machining center is maintained. The numerical control machining center drives the cutter to rotate at a high speed through the main shaft, so that the workpiece is machined. When the main shaft rotates at a high speed, on one hand, the main shaft drives a cutter cutting part to generate a large amount of heat, and on the other hand, the bearing also generates a large amount of heat when rotating at a high speed, and finally the temperature of the main shaft is increased; and further, the machining precision of the machining center is influenced, and in order to cool the main shaft, a cooling system is additionally arranged in the main shaft sleeve, so that the main shaft is cooled through heat dissipation of the cooling system. The existing spindle cooling systems mainly comprise two types, one type is that a spiral cooling groove is arranged on the outer cylindrical surface of a spindle sleeve, and after the spindle sleeve is arranged on a spindle sleeve seat, the cooling groove and the inner ring wall of the spindle sleeve seat form a cooling loop; the other type is that the axial direction of the main shaft sleeve is provided with cooling holes which are connected in series, two ends of the main shaft sleeve are provided with flange plates, the flange plates are provided with fan-shaped grooves, and the axial holes on the main shaft sleeve are sequentially connected in series through the fan-shaped grooves on the flange plates at the two ends to form a cooling loop; however, both cooling methods are only suitable for use with spindle noses that are located very close to the spindle pocket mounting surface, with the bearing locations within the cooling range of the cooling slot. However, a large number of complex workpieces require the spindle nose to be very close to the workpiece, and generally require the distance between the spindle nose and the mounting surface of the spindle sleeve seat to be between 100 mm and 200mm, so that the front end bearing of the spindle is far away from the cooling range of the cooling tank, and the temperature rise of the front end of the spindle is difficult to reduce.

In addition, the existing spiral cooling groove is generally arranged on the outer cylindrical surface of the main shaft sleeve, the mounting surface of the main shaft sleeve is far away from the end surface of the main shaft, the front bearing of the main shaft is not in the cooling range of the spiral cooling groove, and the heat at the front bearing of the main shaft cannot be dissipated in time, so that the machining precision of the main shaft is influenced.

Disclosure of Invention

The invention aims to provide a cooling structure of a main shaft of a numerical control machining center, and aims to solve the problems that the distance between the nose end of the main shaft and the mounting surface of a main shaft sleeve seat is large, a bearing at the front end of the main shaft is far away from the cooling range of a cooling groove, and the temperature rise at the front end of the main shaft is difficult to reduce.

The technical scheme adopted by the invention is as follows:

the invention provides a main shaft cooling structure with annular cooling and axial cooling connected in series, which mainly comprises a main shaft sleeve, a main shaft sleeve seat, a flange plate, an end face sealing ring and a radial sealing ring; the middle part of the main shaft sleeve is provided with a circle of bulges, one side of each bulge is connected with a main shaft sleeve seat sleeved on the main shaft sleeve, and two ends of the main shaft sleeve seat are sealed with the main shaft sleeve through radial sealing rings; the end face of the main shaft sleeve positioned on the other side of the bulge is connected with the flange plate, and the main shaft sleeve and the flange plate are sealed through an end face sealing ring; the two ends of the outer cylindrical surface of the spindle sleeve arranged in the spindle sleeve seat are provided with sealing ring grooves for mounting the radial sealing rings, a hoop cooling pipeline is arranged on the spindle sleeve section between the two sealing ring grooves, an axial hole cooling pipeline is arranged on the rest section of the spindle sleeve, one end of the axial hole cooling pipeline is connected with the hoop cooling pipeline in series to form a circulating cooling loop, and the other end of the axial hole cooling pipeline is communicated with the fan-shaped grooves on the flange plate.

As a further technical scheme, the annular cooling pipeline comprises a first annular groove, a plurality of spindle sleeve seat fan-shaped grooves, a middle annular groove, a spiral cooling groove and a second annular groove which are sequentially arranged from the middle position of the spindle sleeve seat to one end.

As a further technical scheme, the first annular groove is communicated with a cooling liquid inlet positioned on the main shaft sleeve seat; the second annular groove is communicated with a cooling liquid outlet positioned on the spindle sleeve seat.

As a further technical scheme, the spindle sleeve seat sector-shaped groove is arranged along the circumferential direction of the spindle sleeve.

As a further technical solution, the axial hole cooling pipeline includes a first axial hole, a second axial hole and a third axial hole; the first axial hole is communicated with the first annular groove through a first radial hole; the second axial hole is communicated with the second annular groove through a second radial hole; the third axial hole and the third radial hole are communicated with the spindle sleeve seat sector groove.

As a further technical scheme, the numbers of the third axial holes, the third radial holes and the spindle sleeve seat sector-shaped grooves are equal.

As a further technical scheme, the drift diameters of the first annular groove, the plurality of spindle sleeve seat fan-shaped grooves, the middle annular groove, the spiral cooling groove, the second annular groove, the first axial hole, the second axial hole, the third axial hole and the flange plate fan-shaped groove are consistent.

As a further technical scheme, a liquid discharge hole is further formed in the spindle sleeve seat and is located in the non-matching section of the spindle sleeve seat and the spindle sleeve.

In a second aspect, the invention further provides a machine tool, which comprises the spindle cooling structure and a spindle, wherein the spindle is matched with the spindle sleeve through a bearing.

The cooling circuit is located between the radial seal ring and the end face seal ring. And a cooling pipeline at the spiral cooling groove is connected in series with a cooling pipeline formed by connecting the plurality of axial holes in series to form a complete cooling loop, so that cooling liquid entering the cooling loop flows in a circulating manner.

The invention has the beneficial effects that:

1. the invention realizes the series connection of the annular cooling pipeline and the axial hole cooling pipeline on the main shaft sleeve, has compact structure, realizes the design of a main shaft cooling loop in a limited space, and realizes the cooling of the bearing at the front end of the main shaft;

2. compared with the existing main shaft cooling structure, the main shaft cooling structure provided by the invention can reduce the temperature rise of the main shaft by 5-8 ℃, reduce the temperature rise of the main shaft by 30-40%, and greatly ensure the processing precision of a processing center;

3. the first annular groove and the second annular groove are respectively communicated with the cooling liquid inlet and the cooling liquid outlet, and the cooling liquid inlet and the cooling liquid outlet can be arranged at any 360-degree position in the circumferential direction according to a specific structure; the size of the sector angle of the sector-shaped grooves of the spindle sleeve seats is related to the density of the axial holes, the denser the axial holes are, the better the cooling effect is, the design of the axial holes is as dense as possible under the condition of structural allowance, and the cooling effect of the front end of the spindle is ensured; the middle annular groove is communicated with a first radial hole, and the first radial hole can be arranged at any 360-degree position in the circumferential direction according to a specific structure; the spiral cooling groove mainly cools heat of the main shaft sleeve, and then cools a bearing at the rear end of the main shaft.

4. The pipeline drift diameters on the main shaft cooling structure are designed to be the same, so that the cooling liquid in the cooling pipeline can flow at a constant speed;

5. the sealing ring used by the sealing groove on the peripheral end face of the flange sector groove is a standard O-shaped sealing ring, and the appropriate standard O-shaped sealing ring is selected by calculating the length of the contour line of the sealing groove, so that the timeliness of replacement and good sealing performance of the sealing ring are ensured.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

Fig. 1 is an exploded view of the structure provided by the present invention.

Fig. 2 is a front view provided by the present invention.

Fig. 3 is a right side view provided by the present invention.

FIG. 4 is a schematic sectional view of the structure of A-A provided by the present invention.

FIG. 5 is a cross-sectional view B-B of the coolant entering the flange sector slots provided by the present invention.

Figure 6 is a cross-sectional view of a spindle cover segment C-C provided by the present invention.

FIG. 7 is a cross-sectional view of a flange segment groove D-D provided by the present invention.

FIG. 8 is a cross-sectional view of the coolant provided by the present invention entering the intermediate annular groove E-E from the flange sector groove.

Fig. 9 is a partial enlarged view of F in fig. 5 according to the present invention.

In the figure: 1 end face sealing ring, 2 flange plates, 3 first cylindrical roller bearing, 4 main shaft bearing, 5 main shaft sleeve, 6 right radial sealing ring, 7 main shaft sleeve seat, 8 second cylindrical roller bearing, 9 cooling liquid inlet, 10 right annular groove, 11 cooling liquid inlet radial hole, 12 first axial hole, 13 flange plate sector groove, 14 second axial hole, 15 first radial hole, 16 middle annular groove, 17 spiral groove, 18 left annular groove, 19 left radial sealing ring, 20 cooling liquid outlet, 21 leakage port, 22 third axial hole, 23 second radial hole, 24 main shaft sleeve sector groove and 25 third radial hole.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an", and/or "the" are intended to include the plural forms as well, unless the invention expressly state otherwise, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;

for convenience of description, the words "left" and "right" when appearing in the present disclosure are intended to correspond only to the left and right directions of the drawings themselves, and not to limit the structure, but merely to facilitate the description of the disclosure and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present disclosure.

As introduced by the background art, the defects in the prior art are overcome, and in order to solve the technical problems, the invention provides a spindle cooling structure and a machine tool with annular cooling and axial cooling connected in series, wherein a right annular groove, a plurality of uniformly arranged fan-shaped grooves, a middle annular groove, a spiral cooling groove and a left annular groove are sequentially arranged on the outer cylindrical surface of a spindle sleeve installed in a spindle sleeve seat from right to left; the right end of the main shaft sleeve is provided with a plurality of axial holes, and the axial holes are sequentially connected in series with the end face sealing ring and the sector groove on the outer cylindrical surface through the sector groove on the flange plate to form a cooling pipeline; the cooling pipelines at the spiral cooling grooves are communicated in series with the cooling pipelines at the plurality of axial holes through the middle annular groove, the radial holes and the axial holes to form a complete cooling loop, so that cooling liquid entering the cooling pipelines flows circularly; two sets of radial sealing rings are arranged on the left and right sides of the outer cylindrical surface of the main shaft sleeve arranged in the main shaft sleeve mounting seat, a plurality of end face sealing rings are arranged at the joint of the other end of the main shaft sleeve and the flange plate, and the cooling loop is positioned between the radial sealing rings and the end face sealing rings.

The invention provides a main shaft cooling structure with a spiral groove and a plurality of axial holes connected in series, which mainly comprises an end face sealing ring 1, a flange plate 2, a main shaft bearing 4, a main shaft sleeve 5, a right radial sealing ring 6, a main shaft sleeve seat 7, a cooling liquid inlet 9, a right annular groove 10, a cooling liquid inlet radial hole 11, a first axial hole 12, a flange plate fan-shaped groove 13, a second axial hole 14, a first radial hole 15, a middle annular groove 16, a spiral groove 17, a left annular groove 18, a left radial sealing ring 19, a cooling liquid outlet 20, a leakage opening 21, a third axial hole 22, a second radial hole 23, a main shaft sleeve fan-shaped groove 24, a third radial hole 25 and the like, and has the following specific structure:

in one embodiment of the present invention, as shown in fig. 4 to 8, the spindle cooling structure with spiral grooves connected in series with axial holes is provided with a plurality of flange sector grooves 13, a plurality of third axial holes 22, a plurality of third radial holes 25, a plurality of spindle cover sector grooves 24, a first axial hole 12 and a second axial hole 14.

Sealing ring grooves are formed in the left end and the right end of the outer cylindrical surface of the main shaft sleeve 5 installed in the main shaft sleeve seat 7, a right annular groove 10, a plurality of main shaft sleeve fan-shaped grooves 24, a middle annular groove 16, a spiral groove 17 and a left annular groove 18 are sequentially formed between the two sealing ring grooves from right to left, and the main shaft sleeve fan-shaped grooves 24 are uniformly arranged on the annular end surface of the main shaft sleeve, specifically referring to fig. 6; the right annular groove 10 is communicated with a cooling liquid inlet 9, and the cooling liquid inlet 9 is arranged on the spindle sleeve seat 7; the left annular groove 18 is communicated with a cooling liquid outlet 20, and a cooling liquid inlet 9 is arranged on the spindle sleeve seat 7; the right radial sealing ring 6, the right annular groove 10, the plurality of spindle sleeve fan-shaped grooves 24, the middle annular groove 16, the spiral groove 17, the left annular groove 18, the left radial sealing ring 19 and the spindle sleeve seat 7 form a spindle sleeve left end cooling pipeline;

a plurality of third axial holes 22, a first axial hole 12 and a second axial hole 14 which are uniformly distributed are formed in the right end of the main shaft sleeve 5, wherein one end of the first axial hole 12 is communicated with the right annular groove 10 through a cooling liquid inlet radial hole 11, and the other end of the first axial hole is communicated with the flange sector groove 13; one end of the second axial hole 14 is communicated with the middle annular groove 16 through a first radial hole 15, and the other end is communicated with the flange sector groove 13; the one end of third axial hole 22 is passed through radial hole 23 and main shaft cover sector groove 24 intercommunication, the other end with ring flange sector groove 13 intercommunication, a plurality of ring flange sector grooves 13, third axial hole 22, radial hole 23 and main shaft cover sector groove 24 communicate in proper order, 2 terminal surfaces of ring flange with the 5 links of main shaft cover are equipped with a plurality of sector grooves, ring flange sector groove 13 corresponds the sector groove periphery and is equipped with the end face seal groove, reachs the girth of seal groove through calculating to select suitable standard O type sealing washer as end face seal 1. The cooling liquid inlet radial hole 11, the first axial hole 12, the plurality of flange fan-shaped grooves 13, the plurality of end face seal rings 1, the plurality of third axial holes 22, the plurality of radial holes 23 and the plurality of main shaft sleeve fan-shaped grooves 24 form a cooling pipeline at the right end of the main shaft sleeve 5. The cooling pipelines at the left end and the right end of the main shaft sleeve 5 are communicated through a middle annular groove 16, a first radial hole 15 and a second axial hole 14 to form a complete circulating cooling loop, so that cooling liquid entering the cooling loop flows circularly. The cooling loop is located among the right radial sealing ring 6, the end face sealing rings 1 and the left radial sealing ring 19, and reliable sealing is achieved through the radial sealing rings and the end face sealing rings.

The annular groove, the spiral groove 17, the main shaft sleeve fan-shaped groove 24, the axial hole and the flange disc fan-shaped groove 13 are designed to be consistent in drift diameter size, so that the cooling liquid can circulate at a constant speed conveniently, and a proper cooling drift diameter is designed according to the required temperature rise of the main shaft.

The right annular groove 10 and the left annular groove 18 which are arranged in the embodiment are respectively communicated with a cooling liquid inlet and a cooling liquid outlet, and the cooling liquid inlet and the cooling liquid outlet can be arranged at any 360-degree position in the circumferential direction according to a specific structure; the size of the sector angle of the sector-shaped grooves of the spindle sleeve seats is related to the density of the axial holes, the denser the axial holes are, the better the cooling effect is, the design of the axial holes is as dense as possible under the condition of structural allowance, and the cooling effect of the front end of the spindle is ensured; the middle annular groove 16 is communicated with a first radial hole, and the first radial hole can be arranged at any 360-degree position in the circumferential direction according to a specific structure; the spiral groove 17 mainly functions to cool the heat of the main shaft sleeve, thereby cooling the main shaft rear end bearing.

The coolant flow sequence is as follows:

as shown in fig. 4, the cooling liquid enters the right annular groove 10 from the cooling liquid inlet 9; as shown in fig. 5, through the coolant inlet radial hole 11 into the first axial hole 12; as shown in fig. 7, then through the flange sector 13 into the third axial bore 22; as shown in fig. 6, the cooling liquid enters the main shaft sleeve fan-shaped groove 24 through the second radial hole 23, the cooling liquid enters the middle annular groove 16 through the first radial hole 15, the middle annular groove 16, the spiral groove 17 and the left annular groove 18 sequentially through the plurality of main shaft sleeve fan-shaped grooves 24, the plurality of third radial holes 25, the plurality of third axial holes 22 and the plurality of flange plate fan-shaped grooves 13, the second axial hole 14 is communicated with the middle annular groove 16, the cooling liquid finally enters the cooling liquid outlet 20 through the middle annular groove 16, the spiral groove 17 and the left annular groove 18 sequentially, the cooling liquid outlet 20 is connected to an inlet of a cooling device (not shown in the figure), an outlet of the cooling device is connected to the cooling liquid inlet 9, and thus a complete cooling cycle is completed.

In addition, the implementation also provides a machine tool which comprises a main shaft, the main shaft sleeve and a matched structure, wherein the main shaft and the bearing are installed in the main shaft sleeve, and the heat of the main shaft and the bearing is taken away through cooling liquid in a cooling loop on the main shaft sleeve.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.