JPH057231Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a heat treatment jig for suppressing the occurrence of distortion particularly during heat treatment of thin precision parts.

(Prior Art) When a thin precision part, for example, the outer peripheral part 1a of the synchronizing mesh ring 1 of an automobile transmission as shown in FIG. To prevent this, a jig as shown in FIG. 4 is used. That is, the jig has an outer diameter part 2a that fits into the inner diameter part 1b of the synchronized meshing ring (hereinafter referred to as a workpiece) 1, and is attached to a vertically movable plunger P of a heat treatment machine (quenching machine). A jig with the above configuration was set in a quenching machine, consisting of a plug 2 and a lower mold plate 4 which was mounted on a support ring 3 provided on the top surface of the bed B of the machine and had a hole 4a through which the plug 2 passed. After that, the workpiece is placed in a predetermined position on the lower mold plate 4, and the upper surface 1d of the workpiece is first pressed with the upper mold U. Next, the plunger P is raised and the outer diameter part of the plug 2 attached to it is pressed. 2a
is fitted into the inner diameter portion 1b of the workpiece 1, and in this state, the outer peripheral portion 1a is hardened (oil hardened) as described above.

By using the above jig, it is possible to prevent heat treatment distortions such as tapering and dulling of the inner diameter portion 1b of the workpiece 1.

In general, as a heat treatment jig, for example, as shown in Fig. 2 of Japanese Utility Model Application No. 59-95152 (the number inside the bracket represents the number used in the same publication), a tray 2 is used.
There is also a type in which vertical rods 3 having a Y-shaped cross section with equal spacing that fit into the inner diameter of the component 1 are erected.

(Problems to be solved by the invention) Among the above conventional techniques, in the former, the runout of the end surface 1c of the workpiece 1, that is, the end surface 1c and the inner diameter portion 1b.
There is a problem in that it is difficult to obtain a satisfactory value for the perpendicularity with.

This is because it is difficult to increase the perpendicularity between the upper surface 4b of the lower mold plate 4, which is fixed among the components of the jig, and the outer diameter portion 2a of the plug 2, which is attached to the moving vertically movable plunger P. In order to increase this perpendicularity, the perpendicularity between the lower surface A and the peripheral surface B of the support ring 3 that supports the lower mold plate 4, the perpendicularity between the lower surface C and the peripheral surface D of the lower mold plate 4, and the perpendicularity between the lower surface A and the peripheral surface D of the lower mold plate 4, and Parallelism of C, above C and upper surface 4b of lower die plate 4
It is also necessary to improve the accuracy of parallelism, etc., and there is a drawback that it requires a large amount of processing man hour (MANHOUR) cost.

Furthermore, the heat treatment jig shown in the latter Utility Model Publication is capable of attaching the tray 2 by inserting a protrusion formed at the lower end of the vertical rod 3 into a small hole made in the tray 2.
However, the protruding portion is loosely fitted into the small hole, and there is a gap between the inner diameter of the component and the outer circumference of the vertical rod 3, so that the end surface of the component 1 and the inner diameter are separated. It is difficult to improve the accuracy of the perpendicularity with

In view of the above, the present invention was devised for the purpose of preventing the heat treatment distortion, particularly in thin precision parts that are easily deformed by heat treatment.

(Means for Solving the Problems) The present invention will be explained with reference to FIGS. 1 and 2, which correspond to embodiments. A plug 5 which is equipped with a vertically movable plunger P of a heat treatment machine;
A lower mold plate 6 is integrally fixed to the lower end of the plug 5, has an upper surface 6a perpendicular to the plug outer part 5a, and has a keyway 6b formed on the outer periphery, and is supported by the bed B of the machine, A hole 7a is provided through which the plate 6 passes, and the key groove 6b is provided in the hole 7a.
It consists of a support ring 7 provided with a key 8 that fits into the support ring 7.

(Function) After setting the jig with the above configuration into a heat treatment machine (quenching machine), the workpiece 1 is lightly fitted onto the upper end of the outer diameter portion 5a of the plug 5, and the upper mold U of the machine is lowered. Then, the lower end of the upper mold U presses the upper end surface 1d of the workpiece 1, and the inner diameter part 1b is firmly fitted into the outer diameter part 5a of the plug 5, and the workpiece 1 is pushed down. Finally, the lower end surface 1c of the workpiece 1 is brought into contact with the upper surface 6a of the lower die plate 6. In this state, if the outer peripheral part 1a of the workpiece 1 is hardened (oil hardened) using the heat treatment machine, the perpendicularity between the end face 1c and the inner diameter part 1b of the workpiece 1 is accurately maintained. will be held.

When hardening is finished, first operate the vertical plunger P downward, and the plug 5 and the lower mold plate 6 will move downward, and at this time, the key groove 6b of the lower mold plate 6 will align with the key 8 of the support ring 7. Since the lower die plate 6 is guided by the key 8, it passes through the hole 7a of the support ring 7, contacts the bed B, and stops. As a result, the plug 5 comes off from the inner diameter portion 1b of the workpiece 1, so the upper mold U can be raised at this point to take out the workpiece 1.

(Embodiment) An embodiment of the present invention will be explained with reference to Figs. 1 to 3. 1 is a workpiece, which is a synchronizing mesh ring often used in automobile transmissions, and an outer peripheral portion 1a has a shift ring. A groove 1e into which a fork (not shown) fits and slides (rotationally slides) is formed, and an internal spline is formed in the inner diameter portion 1b. What is important for this part is the improvement of the surface finishing accuracy, as well as the improvement of the end face
This is to ensure the perpendicularity between c, 1d and the inner diameter portion 1b,
If the perpendicularity cannot be obtained accurately, the end faces 1c, 1
d causes uneven contact with adjacent gears, resulting in a lack of smooth synchronous operation and accelerated wear. However, since the above-mentioned parts are thin parts, they are likely to be deformed during heat treatment.

Reference numeral 5 denotes a plug that has an outer diameter portion 5a that fits into the inner diameter portion 1b of the workpiece 1 and is attached to the vertically movable plunger P of the heat treatment machine. It is formed so that it fits tightly into the cylinder and forms an accurate cylinder.

6 is integrally fixed to the lower end of the plug 5,
It is a lower mold plate having an upper surface 6a on which the workpiece 1 is placed, which is perpendicular to the outer diameter portion 5a of the plug, and key grooves 6b are formed at four locations equally around the circumference on the outer periphery.

The lower mold plate 6 is made relatively thin so as not to be deformed by the pressure of the upper mold U of the heat treatment machine on the workpiece 1, and the required stroke of the plug 5 and the lower mold plate 6 by the vertically movable plunger P is Reduce. The important thing is that the upper surface 6 of the lower die plate 6
a and the outer diameter portion 5a of the plug 5 are formed to be exactly at right angles.

Reference numeral 7 denotes a support ring, which is provided with a hole 7a through which the lower die plate 6 passes, and has four keys 8 fitted in the hole 7a to fit into the key groove 6b. Most of them are embedded and installed. The support ring 7 has its upper and lower surfaces 7b and 7c parallel to each other and its upper and lower surfaces 7b and 7c.
It is necessary to maintain the perpendicularity between and the circumferential surface 7d.

After the jig of the present invention constructed as described above is set in the heat treatment machine as shown in the figure, the vertically movable plunger P is operated upward, and the plug 5 and the lower die plate 6 are moved to the position shown in Fig. 2, that is, the lower die. Raise the plate 6 to a position where the lower surface thereof is flush with the upper surface 7b of the support ring 7, as shown in FIG. 2, or move the plunger P
Or by rotating the plug 5 and the lower mold plate 6,
The key groove 6b of the lower die plate 6 is shifted from the position of the key 8 of the support ring 7 so that it is supported by the support ring 7.

Here, the workpiece 1 is attached to the outer diameter portion 5a of the plug 5.
When the upper end is lightly fitted and the upper mold U of the heat treatment machine (quenching machine) is lowered, the lower end of the upper mold U presses the upper end surface 1d of the workpiece 1, and the inner diameter part 1b is The workpiece 1 is pressed down while firmly and tightly fitting into the outer diameter part 5a of the plug 5, and the lower end surface 1c of the workpiece 1 is finally brought into contact with the upper surface 6a of the lower die plate 6. In this state, if the outer peripheral part 1a of the workpiece 1 is hardened (oil hardened) using the heat treatment machine, the end face 1c and the inner diameter part 1 of the workpiece 1 are hardened.
Hardening is performed while the perpendicularity with b is maintained accurately.

When the hardening is finished, move the vertical plunger P downward, or rotate the plug 5 and lower mold plate 6 to bring the keyway 6b of the lower mold plate 6 into the position of the key 8 of the support ring 7. If the vertical plunger P is operated downward after matching, the plug 5 and the lower die plate 6 are moved downward.

At this time, since the key groove 6b of the lower mold plate 6 is fitted into the key 8 of the support ring 7, the lower mold plate 6 is guided by the key 8 and the hole 7a of the support ring 7 is inserted.
It passes through and comes into contact with bed B and stops. As a result, the plug 5 comes off from the inner diameter part 1b of the workpiece 1, so the upper die U is raised and the workpiece 1 is removed.
can be taken out.

(Effects of the invention) The heat treatment jig of the present invention has an outer diameter part that fits into the inner diameter part of the workpiece, and has a plug attached to the vertically moving plunger of the heat treatment machine, and a jig that is integrally attached to the lower end of the plug. a lower die plate which is fixed, has an upper surface perpendicular to the outer diameter of the plug, and has a keyway formed on its outer periphery, and is supported by the bed of the machine and has a hole through which the plate passes, and has the keyway formed in the hole. It consists of a support ring with a key that fits into the inner diameter of the workpiece, so that it is integral with the lower end of the plug that has an outer diameter that fits into the inner diameter of the workpiece. By fixing the mold plate, the workpiece can be tightly fitted into the plug, and the lower end surface of the workpiece can be pressed into contact with the upper surface of the lower mold plate. This ensures accurate perpendicularity and prevents distortion of the workpiece due to hardening. Therefore, unlike conventional jigs, there is no need for a large amount of machining man-hours to improve the perpendicularity and parallelism of the support ring itself, the parallelism of the support ring and the lower mold plate, etc. in order to increase the perpendicularity between the plug and the lower mold plate. Costs may also be reduced.

Further, a key groove is formed around the lower die plate, and a hole is provided for the lower die plate to pass through, and a support ring is provided in the hole with a key that fits in the key groove, and is supported on the bed. As a result, even though the plug and the lower die plate are integrated, it is possible to pull the plug downward after heat treatment, and the movement of the vertical plunger, that is, the movement of the plug and the lower die plate, is linear and stable. Since the stop position is also accurately maintained, the workpiece can be set smoothly and accurately.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the workpiece, Fig. 2 is a longitudinal sectional view of the heat treatment jig of the present invention, Fig. 3 is a plan view of the same, and Fig. 4 is a longitudinal sectional view of the heat treatment jig of the present invention.
The figure is a longitudinal sectional view of a conventional heat treatment jig. 1... Workpiece, 1a... Same outer periphery, 1b...
Same inner diameter part, 1c, 1d... Same end surface, 1e... Same groove, 2, 5... Plug, 2a, 5a... Same outer diameter part, 3, 7... Support ring, 4, 6... Lower mold Plate, 6a...Key groove, 8...Key, P...Vertical plunger, U...Upper mold, B...Bed.

Claims (1)

[Scope of utility model registration request] A plug that has an outer diameter portion that fits into the inner diameter portion of the workpiece and is attached to a vertically moving plunger of a heat treatment machine, and a plug that is integrally fixed to the lower end of the plug and has an upper surface that is perpendicular to the outer diameter portion of the plug, and A heat treatment jig comprising a lower die plate with a keyway formed on its outer periphery, a support ring supported by the bed of the machine, having a hole through which the plate passes, and a support ring provided in the hole with a key that fits in the keyway. .