A quenching die for thin-walled bearing inner ring

Abstract

The present invention discloses a quenching die for thin-walled bearing inner rings, comprising three bottom modules, a bottom die support die, an inner diameter limiting die, lower and upper inner diameter supporting dies, lower and upper inner diameter limiting cones, a cover plate, and an end limiting die. The three bottom modules are mounted on three guide rails in a one-to-one correspondence; the bottom die support die is enclosed by three bottom die support modules, each of which is arranged on the inner side of the three bottom modules; the inner diameter limiting die is enclosed by three inner diameter limiting templates, each of which is fixed on the top surface of the three bottom modules in a one-to-one correspondence; the lower and upper inner diameter supporting dies are arranged in a one-to-one correspondence on the lower and upper inner sides of the inner diameter limiting die; the lower and upper inner diameter limiting cones are arranged in a one-to-one correspondence in the inner hole of the bottom die support die and the inner holes of the lower and upper inner diameter supporting dies; the cover plate is arranged on the top surface of the inner diameter limiting cone and the inner diameter upper supporting die; and the end limiting die, on the top surface of which a plurality of butterfly spring washers are arranged, can be movably sleeved on the outer surface of the cover plate. The present invention can greatly reduce the deformation of the thin-walled bearing inner ring.

Description

Technical Field

[0001] The invention relates to a quenching die for a thin-wall bearing inner ring. Background Art

[0002] The inner ring of a thin-walled angular contact ball bearing has a wall thickness-to-diameter ratio of only 1:20 to 1:40, and its wall thickness is unevenly distributed at high temperatures. This makes it very easy for the bearing to warp significantly during the actual quenching process. If the deformation is too large and the allowance is insufficient, it can easily result in heat treatment rejects. Currently, many bearing manufacturers use free quenching or only limit end face die quenching. The drawback is that they often compensate for heat treatment deformation by using a large process design allowance. There is room for improvement as follows:

[0003] 1) The warping deformation of the end face is large, often more than 0.3mm;

[0004] 2) The ellipticity of the inner diameter is relatively large, usually around 0.5mm to 1mm.

[0005] If the above problems are not solved, large subsequent processing allowances cannot be avoided, and it will be difficult to reduce subsequent production rhythm and costs. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a quenching die for the inner ring of a thin-walled bearing, which can greatly reduce the deformation of the inner ring of the thin-walled bearing during the quenching process.

[0007] The object of the present invention is achieved as follows: A quenching die for a thin-walled bearing inner ring comprises three bottom die blocks, a bottom die support die, an inner diameter limiting die, an inner diameter lower supporting die, an inner diameter upper supporting die, an inner diameter lower limiting cone, an inner diameter upper limiting cone, a cover plate and an end limiting die; wherein,

[0008] The bottom module is a rectangular block and a guide rail groove with a T-shaped cross section is provided in the middle of the bottom surface along the longitudinal axis; the longitudinal axes of the three bottom modules intersect at a center point and are arranged at an angle of 120°, and the three bottom modules are equidistant from the center point; the three bottom modules are each slidably mounted on three guide rails through the guide rail grooves; each guide rail includes a guide rail base plate and a guide rail body fixed to the guide rail base plate; the guide rail body has a T-shaped cross section and includes a vertical portion and a transverse portion; the outer surface of the transverse portion has a limit groove provided in the inner side surface direction, and an inner mold outward movement limit rod is installed in the limit groove;

[0009] The outer circumference of the bottom mold support mold is cylindrical, and the inner circumference of the bottom mold support mold is an inverted conical surface. The bottom mold support mold is surrounded by three bottom mold support modules in a 120° fan-shaped ring, and the three bottom mold support modules are arranged one by one on the inner side of the three bottom modules;

[0010] The upper and lower parts of the inner circumference of the inner diameter limiting die are both inverted conical surfaces, the outer circumference of the inner diameter limiting die is cylindrical, and a plurality of annular oil grooves are provided at intervals on the outer circumference, each annular oil groove is fitted with a spring ring, and a limiting ring extends upward from the inner side of the top surface of the inner diameter limiting die; the inner diameter limiting die is enclosed by three inner diameter limiting die plates with 120° fan-shaped rings, and the three inner diameter limiting die plates are fixed to the top surfaces of the three bottom modules one by one by bolts;

[0011] The outer circumferential surfaces of the inner diameter lower support die and the outer circumferential surfaces of the inner diameter upper support die are conical surfaces that correspond one to one with the lower and upper parts of the inner circumferential surfaces of the inner diameter limiting die; the inner circumferential surface of the inner diameter lower support die is a stepped cylindrical shape that is larger at the top and smaller at the bottom, and the inner diameter lower support die is arranged at the lower inner part of the inner diameter limiting die; the inner circumferential surface of the inner diameter upper support die is a conical surface, and the inner diameter upper support die is arranged at the upper inner part of the three inner diameter limiting die plates;

[0012] The outer circumference of the inner diameter lower limiting cone is an inverted conical surface adapted to the inner circumference of the bottom mold supporting mold, and the inner diameter lower limiting cone is arranged in the inner hole of the bottom mold supporting mold;

[0013] The upper portion of the outer circumference of the inner diameter upper limit cone is a conical surface adapted to the inner circumference of the inner diameter upper support die, and the lower portion of the outer circumference of the inner diameter upper limit cone is a stepped cylindrical shape adapted to the inner circumference of the inner diameter lower support die, with the upper portion being larger than the lower portion. The inner diameter upper limit cone is arranged in the inner hole of the inner diameter upper support die and is located on the inner hole step surface of the inner diameter lower support die;

[0014] The cover plate is a solid cylinder with an upper diameter larger than a lower diameter of the cover plate, a middle diameter larger than the upper diameter of the cover plate, and a middle diameter larger than the outer diameter of the limiting ring of the inner diameter limiting die; the cover plate is arranged on the top surface of the inner diameter upper support die and the top surface of the inner diameter limiting cone;

[0015] The end limiting mold is a circular ring and the inner circumference is a stepped cylindrical shape. The upper inner diameter of the end limiting mold is adapted to the lower diameter of the cover plate, the middle inner diameter of the end limiting mold is adapted to the middle diameter of the cover plate, and the lower inner diameter of the end limiting mold is larger than the middle inner diameter of the end limiting mold; the total height of the end limiting mold is smaller than the total height of the cover plate, the upper height of the end limiting mold is smaller than the upper height of the cover plate, the middle height of the end limiting mold is larger than the middle height of the cover plate, and the end limiting mold can be moved downwardly and sleeved outside the cover plate; an annular spring groove is coaxially provided on the top surface of the end limiting mold, and a plurality of butterfly spring washers are arranged in the spring groove in a superimposed manner so that the top surface of the butterfly spring washers is higher than the top surface of the end limiting mold.

[0016] The above-mentioned quenching mold for the inner ring of a thin-walled bearing, wherein the quenching mold also includes three compression spring mechanisms; each compression spring mechanism includes an upright compression spring plate, a horizontally arranged compression spring rod with its outer end fixed on the inner side surface of the compression spring plate, and a compression spring sleeved on the compression spring rod; the compression spring plates of the three compression spring mechanisms are each installed one-to-one on the outer sides of the three guide rails by screws, so that the inner ends of the three compression springs are pressed one-to-one against the outer sides of the three bottom modules.

[0017] The above-mentioned quenching mold for the inner ring of a thin-walled bearing, wherein the inner mold outward movement limit rod is a threaded rod whose length is greater than the width of the transverse part of the guide rail body, so that the inner mold outward movement limit rod is fixed in the limit groove of the transverse part of the guide rail body by installing a clamping nut at each end of the two side surfaces exposed from the transverse part of the guide rail body.

[0018] The above-mentioned quenching die for the inner ring of a thin-walled bearing, wherein a plurality of vertical oil grooves are evenly distributed along the circumference on the outer peripheral surface of the inner diameter limiting die.

[0019] The above-mentioned quenching die for the inner ring of a thin-walled bearing, wherein a plurality of oil grooves are evenly distributed radially on the bottom surface of the end limit die.

[0020] The quenching die for the thin-walled bearing inner ring of the present invention has the following characteristics:

[0021] 1) The cover plate, the inner diameter upper support die and the inner diameter lower support die are pressed down in sequence by the pressing plate, driving the inner diameter limit die to move radially to control the inner diameter of the bearing inner ring, thereby controlling the inner diameter size and ovality of the bearing inner ring during the quenching process;

[0022] 2) By designing the cover plate and the end limit die into a split structure, and movably fitting the end limit die onto the cover plate, a butterfly spring washer is provided on the top surface of the end limit die. When the cover plate moves down to the limit position, the butterfly spring washer is pressed down by the pressure plate, pushing the end limit die to continue to move downward slightly, so that the lower end face of the end limit die is always in close contact with the small end face of the bearing inner ring. This can reduce the end face curvature of the bearing inner ring during the quenching process, and ensure that the bearing inner ring has a better height dimension, end face parallelism and flatness.

[0023] 3) Use the inner diameter lower limit cone and the inner diameter upper limit cone to control the inner diameter of the bearing inner ring to ensure that the bearing inner ring can evenly withstand the extrusion of thermal stress during the quenching process. The opening degree of the entire mold is the same from top to bottom, and the concentricity and vertical difference are good, thereby creating cost reduction and improvement space for subsequent process adjustments.

[0024] 4) It can be automatically demoulded, which is convenient for automated assembly line production and can be used in the quenching process of thin-walled parts with similar structures, with a certain degree of universality.

[0025] 5) After adopting the quenching die of the present invention, the deformation of the inner ring of the thin-walled bearing is significantly reduced compared with free quenching. In addition, since the shape and position dimensions of the thin-walled bearing inner ring are consistent in batches, it provides room for improvement in reducing the overall process margin, compressing the process, and even reducing parts consumables, and has good practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the structure of the quenching die for the inner ring of a thin-walled bearing according to the present invention (semi-axial section before press quenching);

[0027] Figure 2 yes Figure 1 Right side view (lower part) in;

[0028] Figure 3 Schematic diagram of the structure of the quenching die for the inner ring of a thin-walled bearing according to the present invention (semi-axial cross-section during press quenching);

[0029] Figure 4 Schematic diagram of the structure of the quenching die for the inner ring of a thin-walled bearing according to the present invention (semi-axial cross-section of the quenching oil flow direction during the press quenching process);

[0030] Figure 5 It is a structural schematic diagram of a quenching die for a thin-walled bearing inner ring according to the present invention (a semi-axial cross section during demoulding). DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings.

[0032] See also Figure 1 and Figure 2 The quenching die for the inner ring of a thin-walled bearing of the present invention includes three bottom module blocks 2, a bottom die support die 3, an inner diameter limiting die 4, an inner diameter lower supporting die 51, an inner diameter upper supporting die 52, an inner diameter lower limiting cone 61, an inner diameter upper limiting cone 62, three compression spring mechanisms 7, a cover plate 8A and an end limiting die 9.

[0033] The bottom module 2 is a rectangular block, and a guide rail groove with a T-shaped cross section is opened in the middle of the bottom surface of the bottom module 2 along the longitudinal axis; the longitudinal axes of the three bottom modules 2 intersect at a center point and are arranged at an angle of 120 degrees, and the three bottom modules 2 are at the same distance from the center point. The three bottom modules 2 are each slidably mounted on three guide rails 1 through the guide rail groove; each guide rail 1 includes a guide rail base plate 11 and a guide rail body 12 fixed on the guide rail base plate 11; the guide rail body 12 has a T-shaped cross section and includes a vertical portion and a horizontal portion. The outer side of the transverse portion is provided with a limiting groove 13 toward the inner side surface, and an inner mold outward limiting rod 14 is installed in the limiting groove 13. The inner mold outward limiting rod 14 is a threaded rod. The length of the inner mold outward limiting rod 14 is greater than the width of the transverse portion of the guide rail body 12. The diameter of the inner mold outward limiting rod 14 is adapted to the width of the limiting groove 13, so that the inner mold outward limiting rod 14 is fixed in the limiting groove 13 of the transverse portion of the guide rail body 12 by installing a clamping nut 140 at each end of the two side surfaces of the transverse portion exposed to the guide rail body 12.

[0034] The outer circumference of the bottom mold support mold 3 is cylindrical, and the inner circumference of the bottom mold support mold 3 is an inverted conical surface. The bottom mold support mold 3 is surrounded by three bottom mold support modules with 120° fan-shaped rings, and the three bottom mold support modules are arranged one by one on the inner side of the three bottom modules 2.

[0035] The upper part and the lower part of the inner circumference of the inner diameter limiting die 4 are both inverted cone surfaces, the outer circumference of the inner diameter limiting die 4 is cylindrical, and a number of annular oil grooves 40 are arranged at intervals on the outer circumference of the inner diameter limiting die 4, and each annular oil groove 40 is respectively fitted with a spring ring 4A surrounded by a cylindrical spring, and a plurality of vertical oil grooves 41 are evenly distributed along the circumference on the outer circumference of the inner diameter limiting die 4, and a limiting ring 42 extends upward from the inner side of the top surface of the inner diameter limiting die 4; the inner diameter limiting die 4 is enclosed by three inner diameter limiting die plates with a 120° fan-shaped ring, and the three inner diameter limiting die plates are each fixed one by one to the top surface of the three bottom modules 2 by bolts 4B.

[0036] The outer circumference of the inner diameter lower support die 51 is a conical surface that matches the lower part of the inner circumference of the inner diameter limiting die 4; the inner circumference of the inner diameter lower support die 51 is a stepped cylindrical shape with a larger upper part and a smaller lower part, and the inner diameter lower support die 51 is arranged at the inner lower part of the inner diameter limiting die.

[0037] The outer circumference of the inner diameter upper support die 52 is a conical surface that matches the upper inner circumference of the inner diameter limiting die 4; the inner circumference of the inner diameter upper support die 52 is conical, and the inner diameter upper support die is arranged at the inner upper part of the inner diameter limiting die.

[0038] The outer circumference of the inner diameter lower limiting cone 61 is an inverted conical surface adapted to the inner circumference of the bottom mold supporting mold 3 , and the inner diameter lower limiting cone 61 is arranged in the inner hole of the bottom mold supporting mold 3 .

[0039] The upper portion of the outer circumference of the inner diameter upper limit cone 62 is a conical surface that is adapted to the inner circumference of the inner diameter upper support mold 52, and the lower portion of the outer circumference of the inner diameter upper limit cone 62 is a stepped cylindrical shape that is larger at the top and smaller at the bottom that is adapted to the inner circumference of the inner diameter lower support mold 51. The inner diameter upper limit cone 62 is arranged in the inner hole of the inner diameter upper support mold 52 and is located on the step surface of the inner hole of the inner diameter lower support mold 51.

[0040] The compression spring mechanism 7 includes an upright compression spring plate 71, a horizontally arranged compression spring rod 72 with its outer end fixed on the inner side surface of the compression spring plate 71, and a compression spring 73 sleeved on the compression spring rod 72; the three compression spring plates 71 of the compression spring mechanism 7 are each installed one-to-one on the outer side surface of the guide rail base plate 11 of the three guide rails 1 and the outer side surface of the vertical part of the guide rail body 12 through two screws, so that the inner ends of the three compression springs 73 are pressed against the outer sides of the three bottom modules 2 one-to-one.

[0041] The cover plate 8A is a solid cylinder and the outer circumference is a stepped cylindrical shape. The upper diameter of the cover plate 8A is larger than the lower diameter of the cover plate 8A, the middle diameter of the cover plate 8A is larger than the upper diameter of the cover plate 8A, and the middle diameter of the cover plate 8A is larger than the outer diameter of the limiting ring 42 on the inner diameter limiting mold 4; the cover plate 8A is arranged on the top surface of the inner diameter support mold 52 and the top surface of the inner diameter upper limit cone 62.

[0042] The end limiting mold 9 is a circular ring and the inner circumference is a stepped cylindrical shape. The upper inner diameter of the end limiting mold 9 is adapted to the upper diameter of the cover plate 8A, and the middle inner diameter of the end limiting mold 9 is adapted to the middle diameter of the cover plate 8A; the total height of the end limiting mold 9 is less than the total height of the cover plate 8A, the upper height of the end limiting mold 9 is less than the upper height of the cover plate 8A, and the middle height of the end limiting mold 9 is greater than the middle height of the cover plate 8A, and the end limiting mold 9 can be moved downward to be sleeved on the outside of the cover plate 8A; an annular spring groove is coaxially opened on the top surface of the end limiting mold 9, and several butterfly spring washers 9A are arranged in a superimposed manner in the spring groove, so that the top surface of the butterfly spring washers 9A is higher than the top surface of the end limiting mold 9; a plurality of oil grooves 90 are evenly distributed radially on the bottom surface of the end limiting mold 9.

[0043] The quenching die for the thin-walled bearing inner ring of the present invention, when in use, connects the pressure plate 8B above the cover plate 8A to the piston rod of the hydraulic cylinder. When the die is quenched, the bearing inner ring 100 is placed on the bottom module 2 with the small end facing upwards and is sleeved on the outside of the inner diameter limit die 4, and the cover plate 8A is placed in. The piston rod of the hydraulic cylinder extends to drive the pressure plate 8B to press down the cover plate 8A and the several butterfly spring washers 9A on the top surface of the end limit die 9. The downward movement of the cover plate 8A drives the inner diameter upper limit cone 62, the inner diameter lower limit cone 61, the inner diameter lower support die 51 and the inner diameter upper support die 52 to move downward until the step surface between the lower and middle parts of the cover plate 8A hits the top surface of the limit ring 42 of the inner diameter limit die 4, and at the same time, through the inverted conical outer peripheral surface of the inner diameter lower support die 51 and the inner diameter upper support die The inverted conical outer circumference of 52 drives the three inner diameter limiting templates constituting the inner diameter limiting die 4 to move radially outward to limit the inner diameter of the bearing inner ring 100. At the same time, the inverted conical outer circumference of the inner diameter lower limiting cone 61 causes the three bottom die support modules constituting the bottom die support die 3 to move radially outward, and drives the three bottom die modules 2 to move outward along their respective axes one by one until the outer side surfaces of the three bottom die modules 2 contact the inner die outward movement limiting rods 14 on the three guide rails 1 one by one (see Figure 3 ).

[0044] The quenching liquid is divided into central spraying, external spraying, and bottom gushing immersion; the central spraying flows in from the inlet, first cooling and shrinking the bearing inner ring 100 to fit the inner diameter limit die 4, and the external spraying and bottom gushing immediately follow up to perform die quenching. The quenching oil is quickly injected from the central oil inlet, passes through the annular oil groove 40 and the vertical oil groove 41 on the inner diameter limit die 4, and contacts the inner diameter surface of the bearing inner ring 100. Then it overflows from the oil groove 90 on the end limit die 9 above the small end face of the bearing inner ring 100, and cooperates with the external spraying and bottom gushing to quickly immerse the bearing inner ring 100 (see Figure 4 ).

[0045] During the quenching process, the bearing inner ring 100 shrinks due to cooling, and the end face height is reduced. Since the pressure plate 8B presses on several butterfly spring washers 9A, several butterfly spring washers 9A can push the end limit mold 9 to continue to move slightly downward, so that the lower end face of the end limit mold 9 is always tightly attached to the small end face of the bearing inner ring 100, thereby reducing the end face curvature of the bearing inner ring 100 generated during the quenching process.

[0046] After quenching is completed, the piston rod of the hydraulic cylinder retracts, driving the pressure plate 8B to rise, so that the pressure of the butterfly spring washers 9A is released, and the end limit mold 9 is reset, and the cover plate 8A is removed. At the same time, the inner diameter limit mold 4 is retracted to the initial position by the reaction force of the spring rings 4A and the compression springs 73 on the three compression spring mechanisms 7, and pushes the inner diameter upper limit cone 62 and the inner diameter lower limit cone 61 to rise and return to their initial positions, so that the bearing inner ring 100 is demoulded (see Figure 5 ).

[0047] Because the three bottom modules 2 are correspondingly moved on the three guide rails 1 by the reaction force of the three compression springs 73, their return movement may be uneven. However, the multiple spring coils 4A mounted on the inner diameter limiting die 4 ensure that the three inner diameter limiting die plates return to their original positions evenly, achieving the desired demolding effect and simultaneously driving the three bottom modules 2 to return to their original positions synchronously. Therefore, the provision of the compression spring mechanism 7 can extend the life of the spring coils 4A on the inner diameter limiting die 4.

[0048] In the quenching die for thin-walled bearing inner rings of the present invention, the cover plate 8A, end-stop die 9, inner diameter stop die 4, and inner die outward limit rod 14 play a primary role throughout the press-quenching process. The end-stop die 9, along with the three bottom die blocks 2, limits the height of the bearing inner ring 100, thereby achieving optimal height dimensions, end face parallelism, and flatness. The cover plate 8A, inner diameter stop die 4, and inner die outward limit rod 14 limit the inner diameter of the bearing inner ring 100, controlling its inner diameter and ovality. In addition, by designing bottom mold support molds 3, inner diameter lower support molds 51 and inner diameter upper support molds 52 with various diameters, and loosening the clamping nut 140 to move the inner mold outward limit rod 14 to a suitable position in the limit groove 13 of the guide rail 1, and then tightening it with the clamping nut 140, the dimensions of the remaining parts remain unchanged, and it can adapt to bearing inner rings 100 with various inner diameters; in addition, by replacing the end limit molds 9 with different heights, it can adapt to bearing inner rings 100 with different heights.

[0049] The present invention's quenching die for thin-walled bearing inner rings alleviates the existing problem of deformation during quenching of thin-walled bearing inner rings. By employing an automated feeding mechanism, efficient automated production can be achieved. Its principles are generally applicable to similar thin-walled rings and similar parts, effectively improving the press quenching quality and efficiency of thin-walled ring parts.

[0050] The quenching die for the thin-walled bearing inner ring of the present invention has high repeat positioning accuracy, good shape and size consistency of the die-quenched product, and the flatness of the thin-walled bearing inner ring can be controlled within 0.2 mm; the inner diameter ovality of the thin-walled bearing inner ring can be controlled within 0.4 mm.

[0051] The above embodiments are only used to illustrate the present invention, rather than to limit the present invention. Those skilled in the art may make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the scope of the present invention and should be defined by the claims.

Claims

1. A quenching die for a thin-walled bearing inner ring, comprising three bottom die blocks, a bottom die support die, an inner diameter limiting die, an inner diameter lower supporting die, an inner diameter upper supporting die, an inner diameter lower limiting cone, an inner diameter upper limiting cone, a cover plate, an end limiting die, and three compression spring mechanisms; characterized in that: The bottom module is a rectangular block and a guide rail groove with a T-shaped cross section is provided in the middle of the bottom surface along the axis in the longitudinal direction; the axes in the longitudinal directions of the three bottom modules intersect at a center point and are arranged at an angle of 120°, and the distances from the three bottom modules to the center point are the same; the three bottom modules are each slidably mounted on the three guide rails through the guide rail grooves in a one-to-one correspondence; each guide rail includes a guide rail base plate and a guide rail body fixed to the guide rail base plate; the guide rail body has a T-shaped cross section and includes a vertical portion and a transverse portion, the outer surface of the transverse portion is provided with a limiting groove in the inner side surface direction, an inner mold outward movement limiting rod is installed in the limiting groove, the inner mold outward movement limiting rod is a threaded rod with a length greater than the width of the transverse portion of the guide rail body, so that the inner mold outward movement limiting rod is fixed in the limiting groove of the transverse portion of the guide rail body by installing a clamping nut at each end of the two side surfaces exposed from the transverse portion of the guide rail body; The outer circumference of the bottom mold support mold is cylindrical, and the inner circumference of the bottom mold support mold is an inverted conical surface. The bottom mold support mold is surrounded by three bottom mold support modules in a 120° fan-shaped ring, and the three bottom mold support modules are arranged one by one on the inner side of the three bottom modules; The upper and lower parts of the inner circumference of the inner diameter limiting die are both inverted conical surfaces, the outer circumference of the inner diameter limiting die is cylindrical, and a plurality of annular oil grooves are provided at intervals on the outer circumference, each annular oil groove is fitted with a spring ring, and a limiting ring extends upward from the inner side of the top surface of the inner diameter limiting die; the inner diameter limiting die is enclosed by three inner diameter limiting die plates with 120° fan-shaped rings, and the three inner diameter limiting die plates are fixed to the top surfaces of the three bottom modules one by one by bolts; The outer circumferential surfaces of the inner diameter lower support die and the outer circumferential surfaces of the inner diameter upper support die are conical surfaces that correspond one to one with the lower and upper parts of the inner circumferential surfaces of the inner diameter limiting die; the inner circumferential surface of the inner diameter lower support die is a stepped cylindrical shape that is larger at the top and smaller at the bottom, and the inner diameter lower support die is arranged at the lower inner part of the inner diameter limiting die; the inner circumferential surface of the inner diameter upper support die is a conical surface, and the inner diameter upper support die is arranged at the upper inner part of the three inner diameter limiting die plates; The outer circumference of the inner diameter lower limiting cone is an inverted conical surface adapted to the inner circumference of the bottom mold supporting mold, and the inner diameter lower limiting cone is arranged in the inner hole of the bottom mold supporting mold; The upper portion of the outer circumference of the inner diameter upper limit cone is a conical surface adapted to the inner circumference of the inner diameter upper support die, and the lower portion of the outer circumference of the inner diameter upper limit cone is a stepped cylindrical shape adapted to the inner circumference of the inner diameter lower support die, with the upper portion being larger than the lower portion. The inner diameter upper limit cone is arranged in the inner hole of the inner diameter upper support die and is located on the inner hole step surface of the inner diameter lower support die; The cover plate is a solid cylinder with an upper diameter larger than a lower diameter of the cover plate, a middle diameter larger than the upper diameter of the cover plate, and a middle diameter larger than the outer diameter of the limiting ring of the inner diameter limiting die; the cover plate is arranged on the top surface of the inner diameter upper support die and the top surface of the inner diameter limiting cone; The end limiting mold is a circular ring and the inner circumference is a stepped cylindrical shape, the upper inner diameter of the end limiting mold is adapted to the upper diameter of the cover plate, the middle inner diameter of the end limiting mold is adapted to the middle diameter of the cover plate, and the lower inner diameter of the end limiting mold is larger than the middle inner diameter of the end limiting mold; the total height of the end limiting mold is smaller than the total height of the cover plate, the upper height of the end limiting mold is smaller than the upper height of the cover plate, the middle height of the end limiting mold is larger than the middle height of the cover plate, and the end limiting mold can be movably sleeved on the outside of the cover plate downward; an annular spring groove is coaxially provided on the top surface of the end limiting mold, and a plurality of butterfly spring washers are arranged in the spring groove in a superimposed manner so that the top surface of the butterfly spring washers is higher than the top surface of the end limiting mold; Each compression spring mechanism includes an upright compression spring plate, a horizontally arranged compression spring rod with its outer end fixed on the inner side surface of the compression spring plate, and a compression spring sleeved on the compression spring rod; the compression spring plates of the three compression spring mechanisms are respectively installed on the outer sides of the three guide rails by screws, so that the inner ends of the three compression springs are pressed against the outer sides of the three bottom modules one by one.

2. The quenching die for thin-walled bearing inner ring according to claim 1, characterized in that: A plurality of vertical oil grooves are evenly distributed along the circumference on the outer peripheral surface of the inner diameter limiting die.

3. The quenching die for thin-walled bearing inner ring according to claim 1, characterized in that: A plurality of oil grooves are evenly distributed radially on the bottom surface of the end position limiting mold.

Images