阅读说明：本技术 一种渗碳齿轮脉动压力淬火工装和工艺 (Carburized gear pulsating pressure quenching tool and process ) 是由 刘克 杨兵 杨旭弛 尹建华 王倩 朱旭 蒋秋娥 向臻东 于 2019-10-18 设计创作，主要内容包括：本发明公开了一种渗碳齿轮脉动压力淬火工装和工艺,工装包括外底座和压环和顶杆,外底座内安装芯模；所述芯模包括内底座、多个滑块,内底座中心处设有一个阶梯孔,阶梯孔上大下小；多个滑块沿圆周方向均匀布置在阶梯孔的台阶面上,围成一个凹模,凹模中心孔顶部为圆锥形,下部为圆形的阶梯孔；滑块通过滑动螺栓与内底座连接,滑动螺栓中部的滑动部置于内底座侧壁的螺栓孔内,滑动螺栓的螺纹端与滑块连接,滑动螺栓上套装有弹簧,弹簧的两端分别连接内底座和滑块；所述的压环用于压紧齿轮；顶杆底部为锥形,位于凹模正上方。本发明结构简单,操作方便,装卸模方便,生产效率高,使用寿命长,且对渗碳齿轮有良好的矫形效果,保证了产品的质量。(The invention discloses a carburized gear pulsating pressure quenching tool and a process, wherein the tool comprises an outer base, a pressure ring and an ejector rod, and a core mold is arranged in the outer base; the core mold comprises an inner base and a plurality of sliding blocks, wherein a step hole is formed in the center of the inner base, and the step hole is large in upper part and small in lower part; the plurality of sliding blocks are uniformly arranged on the step surface of the stepped hole along the circumferential direction and form a female die in a surrounding manner, the top of the central hole of the female die is conical, and the lower part of the central hole of the female die is a circular stepped hole; the sliding block is connected with the inner base through a sliding bolt, a sliding part in the middle of the sliding bolt is arranged in a bolt hole in the side wall of the inner base, the threaded end of the sliding bolt is connected with the sliding block, a spring is sleeved on the sliding bolt, and two ends of the spring are respectively connected with the inner base and the sliding block; the pressing ring is used for pressing the gear; the bottom of the ejector rod is conical and is positioned right above the female die. The invention has the advantages of simple structure, convenient operation, convenient assembly and disassembly of the die, high production efficiency, long service life, good shape-righting effect on the carburized gear and product quality guarantee.)

1. a carburized gear pulsating pressure quenching tool is characterized in that: comprises an outer base (1), a pressure ring (6) and an ejector rod (8), wherein a core mold is arranged in the outer base (1); the core mold comprises an inner base (2) and a plurality of sliding blocks (3), wherein a stepped hole is formed in the center of the inner base (2), and the stepped hole is large in upper part and small in lower part; the plurality of sliding blocks (3) are uniformly arranged on the step surface of the stepped hole along the circumferential direction and form a female die in a surrounding manner, the top of the central hole of the female die is conical, and the lower part of the central hole of the female die is a circular stepped hole; the sliding block (3) is connected with the inner base (2) through a sliding bolt (5), a sliding part (51) in the middle of the sliding bolt (5) is arranged in a bolt hole in the side wall of the inner base (2), a threaded end (52) of the sliding bolt (5) is connected with the sliding block (3), a spring (4) is sleeved on the sliding bolt (5), and two ends of the spring (4) are respectively connected with the inner base (2) and the sliding block (3); the pressing ring (6) is used for pressing the gear; the bottom of the ejector rod (8) is conical and is positioned right above the female die.

2. The carburized gear pulsating pressure quenching tool as claimed in claim 1, which is characterized in that: clamping ring (6) include annular internal pressure ring (61) and outer pressure ring (62), internal pressure ring (61) and outer pressure ring (62) are coaxial, internal pressure ring (61) are located between outer pressure ring (62) and ejector pin (8).

3. The carburized gear pulsating pressure quenching tool as claimed in claim 2, which is characterized in that: the top surface of the outer base (1) is provided with a plurality of convex blocks (11) and two lifting bolt holes (12), and the convex blocks (11) are uniformly arranged along the circumferential direction and are positioned right below the outer pressure ring (62); the top surface of the inner base (2) is provided with a plurality of lugs (21), and the lugs (21) are uniformly arranged along the circumferential direction and used for supporting the inner hole of the gear.

4. The carburized gear pulsating pressure quenching tool of claim 1, characterized in that: the outer cylindrical surface of the sliding block (3) is provided with a plurality of square grooves (32), and the square grooves (32) are arranged along the bus of the sliding block (3).

5. The carburized gear pulsating pressure quenching tool of claim 1, characterized in that: the sliding block (3) is made of 20Cr2Ni4A alloy steel, the hardness of the base body of the sliding block (3) is 43HRC, and the hardness of the surface of the sliding block (3) is more than or equal to 59 HRC; the precision of the conical surface at the top of the sliding block (3) is higher than IT6 level, and the roughness is less than or equal to Ra0.8; the sliding bolt (5) is made of alloy steel, and the hardness of the sliding bolt (5) is 43 HRC; the ejector rod (8) is made of medium carbon alloy steel, the hardness of the ejector rod (8) is 32HRC, and the hardness of the conical surface at the bottom of the ejector rod (8) is more than or equal to 56HRC after induction quenching treatment; the conical surface at the bottom of the ejector rod (8) is ground, the precision is higher than IT6 level, and the roughness is less than or equal to Ra0.8.

6. The carburized gear pulsating pressure quenching tool of claim 2, characterized in that: the bottom surface of the inner compression ring (61) is provided with a plurality of square grooves, the square grooves penetrate through the inner compression ring (61), and the square grooves are uniformly distributed along the circumferential direction; a plurality of round holes (63) are formed in the middle of the inner compression ring (61), are positioned in the same horizontal plane and are uniformly arranged along the circumferential direction; the top of the inner compression ring (61) is provided with a plurality of threaded holes for connecting with an oil press of a quenching machine tool.

7. The carburized gear pulsating pressure quenching tool of claim 2, characterized in that: the bottom surface of the outer pressure ring (62) is provided with a plurality of square grooves, the square grooves penetrate through the outer pressure ring (62), and the square grooves are uniformly distributed along the circumferential direction; a plurality of round holes (64) are formed in the middle of the outer pressure ring (62), the round holes are located in the same horizontal plane and are evenly distributed along the circumferential direction, and a plurality of threaded holes used for being connected with an oil press of a quenching machine tool are formed in the top of the outer pressure ring (62).

8. A carburized gear pulsating pressure quenching process using the carburized gear pulsating pressure quenching tool as claimed in any one of claims 1 to 7, comprising the following processing steps:

1) Carburizing the gear, wherein during the carburizing treatment, the gear is horizontally arranged in a single-layer manner;

2) Firstly, mounting a pulsating pressure quenching tool of a carburized gear on a Gralison quenching press, and respectively connecting a mandril, an inner compression ring and an outer compression ring with three independent oil presses of the Gralison quenching press; then setting machine tool pressure quenching parameters;

3) Heating the gear to 800-820 ℃ and preserving heat for 40-90min, taking out the gear in a red hot state and sleeving the gear into a core mold, starting a press machine, and spraying oil for quenching; the ejector rod (8) and the sliding block (3) of the pulse pressure quenching tool for the carburized gear act to limit the positioning of the inner hole of the gear; the inner compression ring (61) acts on the upper end face of the inner hole of the gear to correct the flatness of the inner hole of the gear; the outer pressing ring (62) acts on the upper end face of the gear tooth part to correct the flatness of the gear tooth part;

4) After the pulse pressure quenching tool of the carburized gear and the gear are cooled, the pulse pressure quenching tool of the carburized gear is taken out of a quenching press, the gear is taken out of a core die, oil stains are removed by adopting a water sand blasting mode, and then finish machining is carried out.

9. the carburized gear pulsating pressure quenching process according to claim 8, wherein in the step 2), specific parameters of machine tool pressure quenching are as follows: pressure applied to the ram of 7200lbs, constant pressure; pressure applied to the inner pressure ring was 4800lbs, pulsation frequency 20 HZ; the pressure applied to the outer pressure ring was 7200lbs, pulsation frequency 20 HZ; keeping the pressure for 1 min; the oil flow was 1041 l.min.

10. The carbon gear pulse pressure quenching process as claimed in claim 8, wherein the initial time for pressing the gear by the inner pressure ring (61) and the outer pressure ring (62) in the step 3) is the same.

Technical Field

The invention belongs to the technical field of gear quenching, and particularly relates to a carburized gear pulsating pressure quenching tool and a carburized gear pulsating pressure quenching process.

Background

Gears are wheel-like mechanical parts that transmit torque by virtue of meshing of teeth. The gear can realize the functions of changing the rotating speed and the torque, changing the motion direction, changing the motion form and the like through the transmission with other toothed mechanical parts. The invention aims to solve the problems that the diameter of a gear is more than or equal to 300mm (shown in figure 2), the cylindrical part of an inner hole is higher than the tooth surface, the material is high-alloy carburizing steel such as 12CrNi3A and the like, the outer teeth are carburized, an inner hole spline is processed after quenching, a small amount of finish machining is left in the quenching stage, and the quenching treatment is directly carried out after the carburization. Because the carburizing temperature is about 930 ℃, the heat preservation time is about 10 hours, the carburizing deformation is large, the subsequent quenching and machining are affected, even the gear is scrapped, and the production cost of the gear is increased.

Disclosure of Invention

In order to solve the technical problems, the invention provides the pulsating pressure quenching tool and the process for the carburized gear, which have the advantages of simple structure, convenience in operation, convenience in die assembly and disassembly, high production efficiency and long service life, have a good shape righting effect on the carburized gear with a high-step inner hole of more than or equal to 300mm, and can ensure the quenching quality of the gear.

The technical scheme adopted by the invention is as follows: a carburized gear pulsating pressure quenching tool comprises an outer base, a pressure ring and a push rod, wherein a core mold is installed in the outer base; the core mold comprises an inner base and a plurality of sliding blocks, wherein a step hole is formed in the center of the inner base, and the step hole is large in upper part and small in lower part; the plurality of sliding blocks are uniformly arranged on the step surface of the stepped hole along the circumferential direction and form a female die in a surrounding manner, the top of the central hole of the female die is conical, and the lower part of the central hole of the female die is a circular stepped hole; the sliding block is connected with the inner base through a sliding bolt, a sliding part in the middle of the sliding bolt is arranged in a bolt hole in the side wall of the inner base, the threaded end of the sliding bolt is connected with the sliding block, a spring is sleeved on the sliding bolt, and two ends of the spring are respectively connected with the inner base and the sliding block; the pressing ring is used for pressing the gear; the bottom of the ejector rod is conical and is positioned right above the female die.

In the carburized gear pulsating pressure quenching tool, the pressing ring comprises an annular inner pressing ring and an annular outer pressing ring, the inner pressing ring and the outer pressing ring are coaxial, and the inner pressing ring is located between the outer pressing ring and the ejector rod.

In the carburized gear pulsating pressure quenching tool, the plurality of protruding blocks and the two lifting bolt holes are formed in the top surface of the outer base, and the plurality of protruding blocks are uniformly arranged in the circumferential direction and are located right below the outer ring.

In the carburized gear pulsating pressure quenching tool, the top surface of the inner base is provided with a plurality of bumps which are uniformly arranged along the circumferential direction and used for supporting the inner hole of the gear.

In the carburized gear pulsating pressure quenching tool, a plurality of square grooves are formed in the outer cylindrical surface of the sliding block and are arranged along the bus of the sliding block.

In the carburized gear pulsating pressure quenching tool, the sliding block is made of 20Cr2Ni4A alloy steel, the hardness of the sliding block substrate is 43HRC, and the hardness of the sliding block surface is more than or equal to 59 HRC; the precision of the conical surface at the top of the sliding block is higher than IT6 level, and the roughness is less than or equal to Ra0.8.

In the carburized gear pulsating pressure quenching tool, the sliding bolt is made of alloy steel, and the hardness of the sliding bolt is 43 HRC.

In the carburized gear pulsating pressure quenching tool, the ejector rod is made of medium carbon alloy steel, the hardness of the ejector rod is 32HRC, and the hardness of the conical surface at the bottom of the ejector rod is more than or equal to 56HRC after induction quenching treatment; the conical surface at the bottom of the ejector rod is subjected to grinding treatment, the precision is higher than IT6 level, and the roughness is less than or equal to Ra0.8.

In the carburized gear pulsating pressure quenching tool, the bottom surface of the inner compression ring is provided with a plurality of square grooves, the square grooves penetrate through the inner compression ring, and the square grooves are uniformly arranged along the circumferential direction; a plurality of round holes are formed in the inner compression ring, are located in the same horizontal plane and are evenly distributed along the circumferential direction, and a plurality of threaded holes used for being connected with an oil press of a quenching machine tool are formed in the top of the inner compression ring.

In the carburized gear pulse pressure quenching tool, the bottom surface of the outer ring is provided with a plurality of square grooves, the square grooves penetrate through the outer ring, and the square grooves are uniformly distributed along the circumferential direction; a plurality of round holes are formed in the inner part of the outer pressure ring, are located in the same horizontal plane and are evenly arranged along the circumferential direction, and a plurality of threaded holes used for being connected with an oil press of a quenching machine tool are formed in the top of the outer pressure ring.

A carburized gear pulsating pressure quenching process utilizing the carburized gear pulsating pressure quenching tool comprises the following processing steps:

1) Carburizing the gear, wherein during the carburizing treatment, the gear is horizontally arranged in a single-layer manner;

2) firstly, mounting a pulsating pressure quenching tool of a carburized gear on a Gralison quenching press, and respectively connecting a mandril, an inner compression ring and an outer compression ring with three independent oil presses of the Gralison quenching press; then setting machine tool pressure quenching parameters;

3) Heating the gear to 800-820 ℃ and preserving heat for 40-90min, taking out the gear in a red hot state and sleeving the gear into a core mold, starting a press machine, and spraying oil for quenching; the action of a mandril and a slide block of the pulsating pressure quenching tool of the carburized gear limits the positioning of the inner hole of the gear; the inner compression ring acts on the upper end face of the inner hole of the gear to correct the flatness of the inner hole of the gear; the outer pressing ring acts on the upper end face of the gear tooth part to correct the flatness of the gear tooth part;

4) After the pulse pressure quenching tool of the carburized gear and the gear are cooled, the pulse pressure quenching tool of the carburized gear is taken out of a quenching press, the gear is taken out of a core die, oil stains are removed by adopting a water sand blasting mode, and then finish machining is carried out.

In the carburized gear pulsating pressure quenching process, in the step 2), the specific parameters of the machine tool pressure quenching are as follows: pressure applied to the ram of 7200lbs, constant pressure; pressure applied to the inner pressure ring was 4800lbs, pulsation frequency 20 HZ; the pressure applied to the outer pressure ring was 7200lbs, pulsation frequency 20 HZ; keeping the pressure for 1 min; the oil flow was 1041 l.min.

In the carbon gear pulsating pressure quenching process, the initial time for pressing the gear by the inner pressure ring and the outer pressure ring in the step 3) is the same.

Compared with the prior art, the invention has the beneficial effects that:

1) the inner base is provided with the convex blocks, the outer base is provided with the plurality of convex blocks, the flatness of the gear is limited, oil flows conveniently, and the quenching effect of the gear can be guaranteed; the outer base is provided with the lifting bolt holes, so that the lifting bolt holes are convenient to mount and dismount; according to the invention, the spring is arranged between the sliding block and the inner base, when the ejector rod rises, the sliding block automatically contracts to form a gap with an inner hole of the gear, so that the material can be discharged conveniently; the outer cylindrical surface of the sliding block is provided with the plurality of square grooves arranged along the bus, so that the straightening effect is achieved, the oil flow is facilitated, and the quenching effect of the gear is further ensured.

2) the sliding block and the sliding bolt are made of alloy steel, the hardness of the base body of the sliding block and the sliding bolt is 43HRC, and the sliding block and the sliding bolt have good toughness; the outer surface of the sliding block is carburized, the hardness of the outer surface of the sliding block is more than or equal to 59HRC, the wear resistance is good, and the service life is long. The conical surface at the bottom of the ejector rod is subjected to induction quenching treatment, the hardness is more than or equal to 56HRC, the wear resistance is good, and the service life is long.

3) The inner oblique conical surface of the sliding block and the outer oblique conical surface of the ejector rod are ground, so that the precision is higher than IT6 level, the roughness is less than or equal to Ra0.8, the influence of tooling manufacturing errors on the shape correcting effect is eliminated, and the gear shape correcting precision is ensured. The square grooves are formed in the lower sides of the inner compression ring and the outer compression ring of the compression ring, and the circular holes are formed in the middle of the compression ring, so that the gear straightening mechanism has a straightening effect, is favorable for oil to flow, and can ensure the quenching effect of the gear.

4) The inner pressure ring and the outer pressure ring are respectively provided with the bolt holes, and the angles and the sizes of the bolt holes are fixed, so that the inner pressure ring and the outer pressure ring can be conveniently installed and detached; the pulse frequencies of the inner pressure ring and the outer pressure ring are consistent, the initial time of pressure application is the same, the deformation of the gear ring can be corrected in the pressure application process, and the quenching internal stress release and the size stability are facilitated in the pressure release process; the internal pressure ring and the external pressure ring have the same pulse frequency and the same initial time of pressure application, the deformation of the gear ring can be corrected in the pressure application process, and the pressure release process is favorable for quenching internal stress release and size stability.

Drawings

FIG. 1 is a schematic sectional structure view of a gear pulsating pressure quenching tool of the invention.

Fig. 2 is a top view of a female mold comprised of slides of the present invention.

Fig. 3 is a semi-sectional structural schematic diagram of a female die consisting of sliders in the invention.

Fig. 4 is a schematic view of the sliding bolt structure of the present invention.

FIG. 5 is a top view of the inner base of the present invention

FIG. 6 is a schematic cross-sectional view of the inner base of the present invention

FIG. 7 is a top view of the outer base of the present invention

FIG. 8 is a schematic view of a gear structure

In the figure: 1. an outer base; 11. a raised block; 2. an inner base; 21. a bump; 22. bolt holes; 3. a slider; 31. a threaded hole; 32. a square groove; 4. a spring; 5. a sliding bolt; 6. pressing a ring; 62. an outer pressure ring; 61. an inner compression ring; 8. and a push rod.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1-7, the gear tooth support device comprises an outer base 1, a pressure ring 6 and a push rod 8, wherein a plurality of convex blocks 11 and two lifting bolt holes 12 are arranged on the top surface of the outer base 1, and the convex blocks 11 are uniformly arranged along the circumferential direction and are used for supporting the gear tooth part. The two hoisting bolt holes 12 are matched with hoisting bolts, so that the hoisting is convenient. The outer base 1 in install the mandrel, the mandrel include interior base 2 and six sliders 3, interior base 2 center department be equipped with a shoulder hole, the shoulder hole is big-end-up, be equipped with six bolt holes 22 on the lateral wall of interior base, bolt hole 22 is the unthreaded hole, six bolt holes 22 are evenly arranged along the circumferencial direction. The plurality of sliding blocks 3 are uniformly arranged on the step surface of the stepped hole along the circumferential direction and form a female die in a surrounding manner, the top of the central hole of the female die is conical, and the lower part of the central hole of the female die is a circular stepped hole; slider 3 is connected with interior base 2 through slide bolt 5, and the screw hole of interior base 2 lateral wall is arranged in to the sliding part 51 at slide bolt 5 middle part, and slide bolt 5's screw thread end 52 is connected with slider 3, and the cover is equipped with spring 4 on the slide bolt 5, and interior base 2 and slider 3 are connected respectively to the both ends of spring 4. The bottom of the ejector rod 8 is conical and is positioned right above the female die. The ejector rod 8 descends, and the diameter of the female die can be expanded through the cooperation with the tapered hole in the top of the female die, so that the inner hole of the gear is fixed.

The outer cylindrical surface of the sliding block 3 is provided with the square grooves 32, and the square grooves 32 are arranged along the bus of the sliding block 3, so that the sliding block 3 is convenient for oil to flow on the basis of gear correction, and the quenching effect of the gear is ensured. The sliding block 3 is made of 20Cr2Ni4A alloy steel, the matrix hardness of the sliding block 3 is 43HRC, and the hardness of the surface of the sliding block 3 is more than or equal to 59 HRC; the sliding bolt 5 is made of alloy steel, and the hardness of the sliding bolt 5 is 43 HRC. This ensures the toughness of the slider 3 and the slide bolt 5, and ensures the wear resistance of the slider 3. The precision of the conical surface at the top of the sliding block 3 is higher than IT6 level, and the roughness is less than or equal to Ra0.8. The ejector rod 8 is made of medium carbon alloy steel, the hardness of the ejector rod is 32HRC, and the hardness of the conical surface at the bottom of the ejector rod is more than or equal to 56HRC after induction quenching treatment; the toughness and the wear resistance of the ejector rod 8 are ensured. The conical surface at the bottom of the ejector rod 8 is ground, the precision is higher than IT6 level, and the roughness is less than or equal to Ra0.8. The influence of the tooling manufacturing error on the shape correcting effect is eliminated, and the gear shape correcting precision is ensured.

Clamping ring 6 include annular internal compression ring 61 and outer pressure ring 62, internal compression ring 61 is coaxial with outer pressure ring 62, internal compression ring 61 is located between outer pressure ring 62 and ejector pin 8. The bottom surface of the inner compression ring 61 is provided with a plurality of square grooves, the square grooves penetrate through the inner compression ring 61, and the square grooves are uniformly distributed along the circumferential direction; a plurality of round holes 63 have been seted up to interior clamping ring 61 middle part position, and a plurality of round holes 63 are located same horizontal plane, and evenly arrange along the circumferencial direction. The bottom surface of the outer pressure ring 62 is provided with a plurality of square grooves, the square grooves penetrate through the outer pressure ring 6, and the square grooves are uniformly distributed along the circumferential direction; a plurality of round holes 64 are formed in the middle of the outer pressure ring 62, and the round holes 64 are located in the same horizontal plane and evenly arranged along the circumferential direction. The top parts of the outer compression ring 62 and the inner compression ring 61 are respectively provided with a plurality of threaded holes for connecting with an oil press of a quenching machine tool. The square grooves and the round holes on the inner compression ring 61 and the outer compression ring 62 enable the oil to have good fluidity, and the quenching effect of the gear can be guaranteed. The bottom of the outer ring 62 presses against the teeth of the gear.

The invention relates to a carburized gear pulsating pressure quenching process, which comprises the following processing steps:

1) the gear is carburized before quenching, and the charging mode of the gear is single-layer flat placement;

2) Before quenching, firstly installing a pulsating pressure quenching tool of the carburized gear on a Grarison quenching press, and respectively connecting the inner compression ring 61, the outer compression ring 62 and the ejector rod 8 with three independent oil presses of the Grarison quenching press; the outer base 1 is installed on a workbench of a quenching machine tool, and the inner base 2, the sliding block 3, the spring 4 and the sliding screw 5 are installed in the outer base 1 after being assembled. Then setting machine tool pressure quenching parameters, wherein the specific parameters of the machine tool pressure quenching are as follows: a pressure of 7200lbs (pounds), constant pressure, applied to the ram 8; pressure applied to the inner compression ring 61 was 4800lbs, pulsation frequency 20 HZ; a pressure 7200lbs applied to the outer ring 62, a pulsation frequency of 20 HZ; keeping the pressure for 1 min; the oil flow was 1041 l.min.

3) During quenching, the gear is heated to 800-820 ℃ and is kept warm for 40-90min to be completely austenitized, the possibility of forming massive ferrite is eliminated, and the microstructure can be fully transformed into martensite in the subsequent quenching process; taking out the gear in the red hot state, sleeving the gear in the core mold, starting a press, and spraying oil for quenching; the mandril 8 acts with the core mould slide block 3 to limit the size of the inner hole of the gear and position the gear; the internal compression ring 61 acts on the upper end face of the inner hole of the gear to correct the flatness of the inner hole of the gear; the outer ring 61 acts on the upper end surface of the gear tooth portion to correct the flatness of the gear tooth portion. The initial time for pressing the gear by the inner pressing ring 61 and the outer pressing ring 62 is the same.

4) After the pulse pressure quenching tool of the carburized gear and the gear are cooled, the pulse pressure quenching tool of the carburized gear is taken out of a quenching press, the gear is taken out of a core die, oil stains are removed by adopting a water sand blasting mode, and then finish machining is carried out.