JP3305662B2 - Workpiece support for induction hardening - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work support used for induction hardening of an annular work, and more particularly to a work support suitable for quenching a thin cylinder or a thin ring.

[0002]

2. Description of the Related Art When induction hardening an annular work such as a cylindrical body or a ring, a work support as shown in FIG. 6 has been used. In other words, the conventional work support 1 has a structure in which a fixed portion 3 made of a small-diameter disk is concentrically superimposed on a support portion 2 made of a large-diameter disk. The annular work 10 to be quenched is placed on the support 2 and is positioned from the inside by the fixing part 3.

In the quenching operation, the work 10 is concentrically supported inside the heating coil 4 by the work support 1, and the heating coil 4 is energized so that the work 10 is energized.
Is heated by high frequency. During heating, the work support 1 rotates around the center, and rotates the work 10 in the circumferential direction. When the heating is completed, the work support 1 descends and the work 1
Is immersed in the quenching liquid 5.

[0004]

By the way, in the induction hardening of an annular work using such a work support,
During heating, it is necessary to support the work 10 at a concentric position inside the heating coil 4 without play. For this purpose, the work support 1 is provided with a fixing portion 3 that fits inside the work 10, and the gap between the work 10 and the fixing portion 3 is set to a diameter difference of about 0.5 mm. ing.

[0005] However, the work 1 is heated by the heating coil 4.
When 0 is heated with high frequency, the work 10 is heated to the quenching temperature, but the heating temperature of the work support 1 is sufficiently lower than the quenching temperature. Therefore, the work 10 expands, but the work support 1 hardly expands. As a result, the gap between the work 10 and the fixed portion 3 is determined by setting the inner diameter of the work 10 to D.
Then, the diameter difference increases to about 0.5 mm + 0.01D. For example, in the case of the work 10 having an inner diameter D of 300 mm, the gap between the work 10 and the fixing portion 3 is about 3.
It increases to 5 mm.

When the work 10 is cooled after the completion of the heating, the work 10 shrinks and the gap with the fixed portion 3 returns to almost the original size.
The binding force for the distortion of 0 is lost, and the distortion is left. For this reason, especially when the work 10 is thin, a remarkable elliptical distortion remains after quenching, and a distortion removing step after quenching is required.

The original gap between the work 10 and the fixed part 3 is also set to be relatively large with a diameter difference of about 0.5 mm.
Since it is a dimension necessary for releasing 0, it is difficult to make this smaller than it is now. Further, extreme restriction of the gap is not preferable from the viewpoint of workability when setting a work.

The present invention has been made in view of the above circumstances, and high frequency quenching capable of suppressing distortion without problem even when the work is thin, without obstructing the attachment and detachment of the work. It is an object of the present invention to provide a work support.

[0009]

In order to achieve the above-mentioned object, a work support for induction hardening according to the present invention supports an annular work when the work is induction hardened by induction heating from the outside. A work support for induction hardening, wherein a base member for supporting the work from below and a predetermined interval in the circumferential direction are arranged on the base member so as to abut on a plurality of circumferential positions on the inner surface of the work. , A plurality of movable heads each of which is movable in the radial direction, and head driving means for urging the plurality of movable heads outward with a uniform pressure in the radial direction.

In the work support for induction hardening according to the present invention, a plurality of movable heads are forcibly retracted inward in the radial direction, and a work is set on the outside thereof. Energize outward with even pressure.
Thereby, the work is uniformly pressed outward at a plurality of positions in the circumferential direction and is fixed. In this state, when the work is heated by high frequency from the outside, the work expands to the outside. However, since the plurality of movable heads follow the expansion and keep the work from the inside, the distortion of the work is suppressed. The work shrinks inward during cooling, but the plurality of movable heads follow this, so that distortion of the work during cooling is also suppressed.

The plurality of movable heads urged radially outward with a uniform pressure easily forcibly retract radially inward by, for example, applying an external force against the urging force. The head does not hinder the attachment / detachment of the work.

Therefore, in the work support for induction hardening according to the present invention, even when the work is thin, distortion of the work is suppressed to such an extent that it is not necessary to correct the work, and the work detachability is not deteriorated.

The operation of forcibly retracting the plurality of movable heads to the inside in the radial direction can be performed manually, but it is more preferable to perform the operation mechanically by head driving means from the viewpoint of operability.

As the head driving means, a guide post vertically erected on the center of the base member, a slide ring externally fitted to the guide post so as to be able to move up and down, and radially arranged outside the slide ring, A plurality of links each of which converts a lifting operation of the slide ring into a reciprocating operation in the radial direction and transmits the reciprocating operation to the movable head, and is provided on a central portion of the base member, and the plurality of movable heads are urged radially outward It shall have a spring for urging the slide ring in the direction.

Because, according to this head driving means,
Since only one spring is required, and the elastic force of the spring is evenly distributed to the plurality of movable heads, the urging forces acting on the plurality of movable heads can be easily equalized without special adjustment. In addition, when the work starts to be distorted, the two movable heads sandwiching the center of the work are pushed toward the center and moved, corresponding to the portion deformed to the inside of the work.
Other movable heads not pushed by the work also move synchronously to the center side. Therefore, the force for preventing the distortion of the work becomes very large. That is, a large restraining force is applied only to the portion that is going to be deformed to the inside of the work. Therefore, distortion of the work is more effectively suppressed.

The spring here is compressed by the operation of a cylinder provided on the central portion of the base member to urge the slide ring in a direction in which the plurality of movable heads are urged radially outward, and It is preferable that the cylinder is configured to drive the slide ring in the reverse direction by the operation in the reverse direction to retract the plurality of movable heads inward in the radial direction.

According to this structure, the operation of forcibly retracting the plurality of movable heads inward in the radial direction is performed mechanically by the head driving means.

It is preferable that the movable head be in contact with a part of the work in the circumferential direction from the inside and to support the part of the work in the circumferential direction from below.

According to this movable head, the followability of the movable head to the distortion of the work is improved.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of a work support for induction hardening according to an embodiment of the present invention, FIG. 2 is a view taken along line AA of FIG. 1, FIG. 3 is a view taken along line BB of FIG. FIG. 4 is an explanatory view of distortion prevention in the work support for induction hardening.

As shown in FIGS. 1 and 2, the induction hardening work support according to the embodiment of the present invention is used for induction hardening of a work 10 formed of a thin ring. The work 10 is supported from below and inside during induction hardening.

The work support includes a disc-shaped base member 20, a shaft member 30 vertically provided through the center of the base member 20, a slide ring 40 externally fitted to the shaft member 30, and A spring 50 which is a coil spring which is located above the slide ring 40 and is externally fitted to the shaft member 30.
And

On the upper surface of the base member 20, as shown in FIG. 2 and the like, a plurality of radially extending grooves 21, 21,... Are formed radially at equal intervals in the circumferential direction. Are formed at 45 ° intervals.
A slider 23 is movably fitted in each groove 21.
As shown in FIG. 3, the slider 23 has overhangs 23a on both lower sides, and the overhangs 23a, 23a
Are held in the groove 21 by a pair of pressers 22 and 22 screwed to the upper surface of the base member 20 so as to engage with the base member 20.

A movable head 24 is provided at the tip of the slider 23.
Are provided integrally, and a connecting portion 25 for connecting to a link 44 described later protrudes from the upper surface of the slider 23. The movable head 24 moves in the radial direction of the base member 20 as the slider 23 moves. This movable head 24
Horizontal first contact surface 24a abutting on the lower surface of work 10
And a second vertical contact surface 24 abutting on the inner surface of the workpiece 10.
b, and supports the work 10 from below and inside.

The shaft member 30 includes a small-diameter guide post 31, a large-diameter portion 32, and a medium-diameter portion 3 integrally formed in order from top to bottom.
3 The guide post 31 protrudes upward through the center of the base member 20. The large-diameter portion 32 supports the base member 20 and is connected to the base member 20 by bolts 34.
It is fixed by.

The slide ring 40 includes the guide post 31
, And is axially movable by a slide bush 41. A ring-shaped stopper 42 is provided below the slide ring 40. The stopper 42 is fitted on the guide post 31 so as not to move in the axial direction.

On the outer surface of the slide ring 40, as shown in FIG. 2 and the like, a plurality of connecting portions 43, 43,. A plurality of connecting portions 43, 43,.
Correspond to a plurality of sliders 23, 23,... Arranged radially on the base member 20. One end of a link 44 is rotatably connected to each connecting portion 43,
The other end of the link 44 is rotatably connected to a connecting portion 25 protruding from the upper surface of the slider 23. Accordingly, the plurality of sliders 23 move radially outward when the slide ring 40 moves down, and move radially inward synchronously when the slide ring 40 moves up.

It is necessary that the plurality of links 44, 44,... Have the same length, but in this case, two brackets 44a, 44
The knuckle structure has a length adjustable by connecting b with a screw rod 44c.

The spring 50 is fitted around the guide post 31 together with the slide ring 40,
It is inserted in a compressed state between the spring retainer 51 and the upper part thereof. Spring retainer 5 fitted externally to guide post 31
1, the fixed position is adjustable in the axial direction to adjust the amount of compression of the spring 50. Reference numeral 52 denotes a spring receiver interposed between the slide ring 40 and the spring 50.

Next, a method of using the work support for induction hardening according to the present embodiment will be described.

The work support for induction hardening is attached to a drive device (not shown) for rotating the work 10 during heating, and lowering the work 10 after heating and immersing the work 10 in a quenching liquid. The length of each of the plurality of links 44 corresponding to the plurality of sliders 23 is set such that the movable ring 24 abuts against the inner surface of the work 10 and the slide ring 40 The stopper 42 is adjusted so as not to contact the stopper 42.

To set the work 10, first, the slide ring 40 is pulled upward against the urging force of the spring 50. Thereby, the sliders 23, 23,.
Move synchronously with the movable heads 24, 24,. Specifically, the movable heads 24, 24,.
Until the diameter of the circle formed by connecting the second contact surfaces 24b becomes smaller than the inner diameter of the workpiece 10.
Increase 0.

Next, the work 10 is placed on the first contact surfaces 24a of the movable heads 24, 24,... And the lifting force applied to the slide ring 40 is removed. As a result, the slide ring 40 is lowered by being pressed by the spring 50, and the sliders 23, 23,.
.. And move synchronously outward in the radial direction, so that the second contact surfaces 24b of the movable heads 24, 24... Abut against a plurality of circumferential positions on the inner surface of the workpiece 10 with uniform pressure.

Thus, the work 10 is supported concentrically with respect to the center of the base member 20.

When the work 10 is supported, the base member 2
While rotating 0 in the circumferential direction, the workpiece 10 is high-frequency heated by an outside heating coil (not shown). When the heating is completed, the base member 20 is lowered, and the work 10 is immersed in a quenching liquid and rapidly cooled.

While the workpiece 10 being heated expands outward,
The plurality of movable heads 24, 24,... Move outward following the expansion, and keep the work 10 from the inside at a predetermined pressure. Therefore, distortion of the workpiece 10 during heating is suppressed. The work 10 shrinks inward during cooling, but the plurality of movable heads 24, 24,... Follow this, so that the distortion of the work 10 during cooling is also suppressed.

If the work 10 is distorted, the work 10 is deformed into an ellipse as shown in FIG. Work 10
The portion deformed inward moves the two movable heads 24, 24 sandwiching the guide post 31 inward, but when the two movable heads 24, 24 move inward, the slide ring 40 rises and the spring 50 is moved. Because of the contraction, the other movable heads 24, 24... From which the work 10 separates also move inward. That is, 2 sandwiching the guide post 31
In order to move the movable heads 24, 24 inward, a force equivalent to moving all the movable heads 24, 24,. Therefore, the force for preventing the distortion of the work 10 becomes extremely large, and the distortion is particularly effectively suppressed.

Now, if there are eight movable heads 24, 24,..., And each pressing force on the work 10 is 5 kg, two movable heads 24, 24 for pressing the inside deformed portion of the work 10 outward. Pressing force is 2
0 kg, which is four times the restraining force as compared with the case where all the movable heads 24 are in contact with the work 10. Therefore, the distortion of the work 10 is effectively suppressed as compared with the case where the movable heads 24 are individually urged.

FIG. 5 is a longitudinal sectional view of a work support for induction hardening according to another embodiment of the present invention, and shows only head driving means for driving a movable head. The parts other than the head driving means are the same as those of the above-described workpiece support for induction hardening, and the same parts are denoted by the same reference numerals.

The head driving means shown here has a double-acting cylinder 60 provided concentrically above the guide post 31. The cylinder 60 includes a plurality of support members 61, 6 erected on the upper surface of the disc-shaped base member 20.
The rod 62, which is fixed downward by 1 and protrudes downward, advances and retreats.

The head 6 attached to the lower end of the rod 62
3 is opposed to the spring retainer 51 externally fitted to the guide post 31 from above. The spring retainer 51 can be moved up and down along the guide post 31 here. The head 63 is also connected to the slide ring 40 by a plurality of vertical arms 64,64. The lower end of each arm 64 is provided with a vertical groove 4 provided on the outer peripheral surface of the slide ring 40.
5, whereby the slide ring 40 can move up and down relative to the arms 64, 64 with a predetermined stroke. As described above, the slide ring 40 is externally fitted to the guide post 3 so as to be able to move up and down.

When the rod 62 of the cylinder 60 rises,
The slide ring 40 is pulled up by the arms 64, 64. Thereby, the plurality of movable heads 24, 2
4 ... are forcibly retracted inward in the radial direction. After the work 10 is placed on the movable heads 24, 24,... In this state, the rod 62 of the cylinder 60 is lowered. As a result, the spring retainer 51 is pressed down to a predetermined position, and the spring retainer 51 is pressed.
Spring 50 interposed between the slide ring 40 and
Are pressed against the plurality of circumferential positions on the inner surface of the work 10 by compressing the movable heads 24.

As described above, the head driving means shown in FIG. 5 urges the movable heads 24, 24... Radially outward by the cylinders 60 and the springs 50, and urges the movable heads 24, 24. Can be forcibly retracted radially inward.

The cylinder 60 may be of a single-acting type. In this case, when the movable heads 24, 24,.
Is forcibly driven upward, and the slide ring 40 is forcibly pulled upward against the urging force of the spring 50.
When the movable heads 24, 24,... Are urged radially outward, the fluid pressure of the cylinder 60 is released, and the slide ring 40 is returned to a state in which it can be moved up and down. Thus, the movable heads 24 are urged radially outward again by the spring 50.

[0045]

As described above, the work support for induction hardening according to the present invention comprises a plurality of movable heads which are urged radially outward with a uniform pressure to cover a plurality of circumferential positions on the inner surface of the work. By uniformly pressing outward, even when the work is thin, distortion of the work is suppressed, and the distortion removing step can be omitted. Therefore, the efficiency of quenching work of a thin work is improved.

In particular, in the case of a configuration in which the elastic force of the spring is distributed to the movable head via a link radially disposed around the spring, a large restraining force is applied only to the portion that is going to be deformed to the inside of the work. Work distortion can be suppressed more effectively.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a work support for induction hardening according to an embodiment of the present invention.

FIG. 2 is a view taken along line AA of FIG.

FIG. 3 is a view taken along a line BB in FIG. 1;

FIG. 4 is an explanatory view of distortion prevention in the work support for induction hardening.

FIG. 5 is a longitudinal sectional view of a work support for induction hardening according to another embodiment of the present invention, and shows only a head driving unit for driving a movable head.

FIG. 6 is an explanatory diagram of quenching using a conventional work support for induction hardening.

[Explanation of symbols]

 Reference Signs List 10 work 20 base member 21 groove 23 slider 24 movable head 30 shaft member 31 guide post 40 slide ring 44 link 50 spring 60 cylinder

Continuation of the front page (56) References JP-A-10-25518 (JP, A) JP-A-11-222621 (JP, A) JP-A-9-249912 (JP, A) Jpn. , U) (58) Fields investigated (Int. Cl. ⁷ , DB name) C21D 1/00 C21D 1/10 C21D 1/18 C21D 1/42 C21D 9/40 H05B 6/00-6/10 H05B 6 / 14-6/44

Claims (4)

(57) [Claims] 1. A high frequency quenching work support for supporting an annular work when the work is quenched by high frequency heating from the outside, comprising: a base member for supporting the work from below; Are arranged at predetermined intervals in the circumferential direction on the base member so as to contact a plurality of locations in the circumferential direction,
A plurality of movable heads each of which is movable in a radial direction, and head driving means for urging the plurality of movable heads outward with a uniform pressure in a radial direction;
The driving means is vertically provided on the center of the base member.
Guide post and the outer
Slide ring and radial outside of the slide ring
, Each of which moves the slide ring up and down
Converted to radial reciprocation and transmitted to the movable head
A plurality of links, provided on a central portion of the base member;
Direction in which multiple movable heads are urged radially outward.
And a spring for urging a slide ring . 2. The apparatus according to claim 1, wherein said head driving means includes a plurality of movable heads.
The workpiece support for induction hardening according to claim 1, wherein the workpiece is forcibly retracted radially inward . 3. The head driving means according to claim 2 , wherein
A guide post that stands vertically above the center of the
A slide ring externally fitted to the post
Radially outside the idling, each
Converting the idling elevating movement to a reciprocating movement in the radial direction
A plurality of links for transmitting to the movable head, and the base
Multiple movable heads are provided on the center of the member
The slide ring urges the slide ring in the direction urged outward.
A spring is provided in the base member.
Compressed by the operation of the cylinder provided on the core,
In the direction in which the multiple movable heads are biased radially outward,
Energizes the ride ring and the cylinder operates in the opposite direction.
Drive the slide ring in the opposite direction to
The workpiece support for induction hardening according to claim 2, wherein the workpiece is forcibly retracted inward in the radial direction . 4. The movable head is a part of a work in a circumferential direction.
Abut from the inside and support the part of the circumferential direction from below
The workpiece support for induction hardening according to claim 1, 2 or 3, wherein