JPH0570807A - Straightening jig - Google Patents

Abstract

PURPOSE:To provide a jig for stably supporting an unstable work and to utilize the jig in the sizing of powder metallurgy. CONSTITUTION:Plural through-holes 24 are radially formed in a cylindrical jig main body 22. A ball 25 is retractably placed in each through-hole 24, and a spring 26 is placed and energized in the direction for the ball 25 to project from the inner periphery of the main body 22. When the axis of the main body 22 is vertical, the balls 25 are positioned at the same height. When a sintered article 1 as the work is inserted into the main body 22 from above, the main body 2 of the sintered article 1 is horizontally placed on the balls 25. The sintered article 1 is pushed downward by the upper sizing punch, hence the ball 25 is retracted, and the sintered article 1 is smoothly drawn out of the main body 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a straightening jig used for sizing in powder metallurgy.

[0002]

2. Description of the Related Art For example, a sintered product 1 such as a joint as shown in FIG. 6 is obtained by molding a raw material powder containing a metal as a main component, sintering the powder, and then performing sizing and other corrections. .. The sintered product 1 has four protrusions 3 projecting from an annular body 2 in the axial direction. These protrusions 3 are separated by 90 °, but the adjacent protrusions 3 project in opposite directions (upward and downward in the drawing). Then, for example, the two protrusions 3 protruding to one side are connected to the driving side, and the two protrusions 3 protruding to the other side are connected to the driven side. In addition, each protrusion 3 also protrudes from the main body portion 2 in the outer peripheral direction.

FIG. 7 shows a turntable 6 used for sizing the sintered product 1 after sintering.
The turntable 6 is rotatably supported on a base 7 by a shaft 8 and has a plurality of storage holes 9 positioned equidistant from the center of rotation. The die 11 is fixed below the locus of the storage hole 9, and a lower punch 12 that moves vertically and is fitted into the die 11 from below is provided. Further, an upper punch 13 is provided which moves in the vertical direction and fits into the die 11 from above. These die 11 and both punches 12 and 13 form a die for sizing. Then, at the time of sizing, first, the sintered product 1 as a work is put into the storage hole 9 of the turntable 6. When the turntable 6 is rotated, the sintered product 1 is transferred to the base 7 together with the turntable 6.
Although it moves up, when the storage hole 9 containing the sintered product 1 before sizing overlaps the die 11, the turntable 6 stops,
Sintered product 1 is placed on lower punch 12, and further lower punch
12 is lowered and the sintered product 1 is fitted into the die 11. Then, the upper punch 13 descends and is fitted into the die 11 through the storage hole 9. In this way, the sintered product 1 is compressed by the punches 12 and 13 in the die 11, and the sizing is performed.
After this sizing, the upper punch 13 rises to come out of the storage hole 9, and the lower punch 12 rises to return the sintered product 1 into the storage hole 9. After the sizing of the sintered product 1 is removed from the mold position by the rotation of the turntable 6, the sintered product 1 is taken out of the turntable 6.

By the way, since the sintered product 1 has two protrusions 3 projecting from the main body 2 in opposite directions, whichever side of the projecting direction is downward, the main body 2 is on a horizontal plane. In the state in which 2 is horizontal, the two protrusions 3 support two points, so that they are not stably supported. As a result, as shown in FIG. 7, the sintered product 1 easily tilts in the storage hole 9 of the turntable 6, and it is difficult to support the main body 2 in a horizontal state. If the sintered product 1 is thus tilted in the storage hole 9, sizing will be hindered.

[0005]

As described above, conventionally, in the case of a work that is difficult to be stably supported, such as a work in which two protrusions protrude in opposite directions from the main body, for example, a sizing die is used. There is a problem that the work tends to incline from the normal posture during transportation to the work, which hinders corrective work such as sizing.

The present invention is intended to solve such a problem, and it is arranged so as to extend in the opposite directions from the main body.
Even if the work has two protrusions, it is possible to maintain the work in a proper posture when it is transferred to a mold for sizing, for example, and to perform correction work such as sizing without trouble. To do.

[0007]

The correction jig of the present invention comprises:
The orthodontic jig according to claim 1, which is for achieving the above-mentioned object, has a substantially cylindrical jig body having an up-down direction as an axial direction, and three places surrounding the center with the jig body. As described above, the jig is provided horizontally and is capable of projecting and retracting from the inner peripheral surface of the jig body and is urged in a direction projecting from the inner peripheral surface.

A correction jig according to a second aspect of the present invention is a jig body having a substantially cylindrical shape having an up-down direction as an axial direction, and a jig body which is embedded horizontally and retractably in an inner peripheral surface of the jig body. And a ring made of an elastic body protruding from the inner peripheral surface of the jig body in a natural state.

[0009]

The straightening jig of the present invention is used, for example, when a work is conveyed to a die for sizing when straightening such as sizing. When the correction jig according to claim 1 is used, a work is fitted from above into a substantially cylindrical jig body, and the work is placed on a support portion protruding from the inner peripheral surface of the jig body. Place it. As a result, even if the work has two protrusions protruding upward and downward from the horizontal main body, the work is supported by the supporting portions that are horizontally arranged at three or more locations surrounding the center of the jig main body. Stable and supported. Then, for example, if the work is pushed downward by an upper punch of a sizing die, the support part is sunk, and the work gets over the support part and comes down from the jig body, but the work is stably supported. By doing so, this work surely moves to the mold in a regular posture.

The same applies to the case of using the correction jig according to the second aspect of the present invention, in which the work is fitted from above into the substantially cylindrical jig body, and the work is fitted to the inner peripheral surface of the jig body. When placed on a ring protruding from the work, the work is stably supported by the horizontal ring. Further, if the work is pushed downward from this state, the ring elastically deforms and sinks, and the work gets over the ring and comes down from the jig body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The sintered product 1 obtained by molding and sintering the raw material powder is the same as that shown in FIG. 6 and FIG. Reference numeral 21 is a straightening jig, and the straightening jig 21 has a jig body 22 made of, for example, iron and having a cylindrical shape. The axial direction is the vertical direction. The inner diameter of the jig body 22 is substantially equal to the outer diameter of the body portion 2 of the sintered product 1. Further, on the inner peripheral surface of the jig body 22, there are four recessed grooves 23 which are vertically fitted and into which the respective protrusions 3 of the sintered product 1 are fitted.
Are formed. Further, in the jig body 22, four through holes 24 are respectively formed between the concave grooves 23 and are formed so as to radially penetrate the center of the jig body 22. These through holes 24
Are located on the same horizontal plane, are at the same height, and are 90 ° apart from each other. Then, in each of the through holes 24, a spherical ball 25 serving as a support, a coil-shaped spring 26, and a screw 27 are housed in this order from the inner peripheral side toward the outer peripheral side. The ball 25 is slidably fitted in the through hole 24 and can be retracted from the inner peripheral surface of the jig body 22. The spring 26 attaches the ball 25 to the jig body.
It is biased in a direction projecting from the inner peripheral surface of 22. Screw
The screw 27 is fixed by being screwed into the through hole 24 and holds the spring 26. The ball 25 is prevented from coming off by a claw portion 28 formed at the tip peripheral edge of the through hole 24 on the inner peripheral surface side of the jig body 22.

The turntable 31 used for sizing the sintered product 1 as a work after sintering is the same as the conventional one, and is made of vinyl chloride resin, for example, and is rotatable by a shaft 33 on a base 32. A plurality of circular storage holes, which are supported by and are equidistant from the center of rotation.
Although it has 34, the diameter of this storage hole 34 is the above-mentioned correction jig.
It is almost the same as the outer diameter of 21. As a result, the correction jig 21 can be detachably fitted into the storage hole 34. Further, the die is located below the locus of the storage hole 34.
36 is fixed and moves up and down to
A lower punch 37 that fits from below is provided inside. Further, an upper punch 38 that moves vertically and is fitted into the die 36 from above is provided. These die 36 and both punches 37, 38 form a die for sizing.

Next, the operation of the above configuration will be described. At the time of sizing, the sintered product 1 is put in the storage hole 34 of the turntable 31 while being supported by the straightening jig 21. That is, the sintered product 1 is placed in the correction jig 21 fitted in the storage hole 34 of the turntable 31. When the turntable 31 rotates in the direction shown by the arrow in FIG.
Put the sintered product 1 in the storage hole 34 of the, and perform sizing with the mold at the position indicated by B, and turntable at the position indicated by C.
The sintered product 1 is taken out from the storage hole 34 of 31. Sintered product 1 is
The main body 2 is made horizontal, and the projection 3 is aligned with the concave groove 23 and fitted into the jig main body 22 of the correction jig 21 from above. In this state, as shown in FIG. 3, the sintered product 1 is placed on the four balls 25 at the same height protruding from the inner peripheral surface of the jig body 22 without the projection 3 contacting the base 7. By mounting the main body 2, the main body 2 is reliably and stably supported in a horizontal posture, and the main body 2 does not tilt. Then, when the turntable 31 rotates, the sintered product 1 is conveyed together with the correction jig 21, but when the sintered product 1 before sizing is carried into the mold position, the turntable 31 is turned on.
31 is stopped, and the sintered product 1 is placed on the lower punch 37. Then,
The upper punch 38 descends and fits into the jig body 22, and the sintered product 1
Press down. As a result, the ball 25 is pushed by the main body 2 of the sintered product 1 and receives the force outward in the radial direction of the jig main body 22,
The ball 25 sinks into the through hole 24 against the force of the spring 26. Along with this, the sintered product 1 gets over the balls 25 and comes out downward from the jig body 22. In the meantime, the lower punch 37 is also lowered so that the sintered product 1 is fitted in the die 36 and the upper punch 38 is fitted in the die 36 through the jig body 22. Then, as shown in FIG. 4, both punches 37, 38 are set in the die 36.
Thereby, the sintered product 1 is compressed and sizing is performed. After this sizing, the upper punch 38 rises and the jig body
As it exits from 22, the lower punch 37 rises and the sintered product 1 returns into the jig body 22. Then, by the rotation of the turntable 31, the sizing sintered product 1 is carried out from the mold position.

As described above, in the above-described embodiment, by using the correction jig 21 in which the balls 25 are projected at the four locations on the inner peripheral surface of the jig body 22 that surround the center of the jig body 22, a horizontal body portion is obtained. Even if the sintered product 1 has two protrusions 3 projecting upward and downward from each of the two, that is, the sintered product 1 that cannot be stably supported by itself in a regular posture in which the main body 2 is horizontal on a horizontal plane, This can be stably supported in a regular posture in which the main body 2 is horizontal. Therefore, by mounting the sintered product 1 on the sizing turntable 31 using the straightening jig 21, the sintered product 1 can be reliably transferred to the sizing die in a proper posture, and sizing can be performed without any problems. You can do it. Further, since the ball 25 can be retracted into and out of the through hole 24 and is urged in a direction projecting from the inner peripheral surface of the jig body 22, the orthodontic jig 21 is transferred from the orthodontic jig 21 to the mold. It is possible to prevent the sintered product 1 from being scratched by simply pushing the sintered product 1 downward when removing the product.

The present invention is not limited to the above embodiment, but various modifications can be made. For example,
The straightening jig 21 of the above-described embodiment is a sintered product 1 in which two protrusions 3 project upward and downward from a horizontal main body 2.
However, the work to be supported is not limited to the sintered product 1 as in the above-mentioned embodiment, and various shapes are possible. Further, the supporting portion provided on the inner peripheral portion of the jig body is not limited to the ball 25 urged by the spring 26 as in the above embodiment. For example,
Like a correction jig 41 of another embodiment shown in FIG. 5, an annular groove 43 is formed in the inner peripheral surface of a cylindrical jig body 42 whose axial direction is the vertical direction.
May be formed horizontally and over the entire circumference, and a rubber O-ring 44, which is a support portion, may be fitted into the annular groove 43. In the correction jig 41 of the other embodiment, in the natural state, the inner peripheral portion of the O-ring 44 projects from the inner peripheral surface of the jig main body 42 and is fitted into the jig main body 42. The combined work is O
It rests on a ring 44 and is supported horizontally. Then, when the work is pushed downward, the O-ring 44 is compressed by the elasticity of the work itself and is recessed in the annular groove 43, and the work is removed from the jig body 42.

[0016]

According to the invention described in claim 1, a jig body having a substantially cylindrical shape and an inner peripheral surface of the jig body which is arranged horizontally at three or more places surrounding the center of the jig body. By using a straightening jig with a support protruding from the
For example, even if a work has two protrusions protruding in opposite directions from the main body, by fitting the work into the jig main body and placing it on the support part, the work can be surely placed in a normal posture. Can be kept. Therefore, for example, the correction work such as the sizing can be performed without any trouble by using the correction jig during the transportation to the sizing die. In addition, since the support part can be retracted from the inner peripheral surface of the jig body and biased in a direction projecting from this inner peripheral surface, for example, when transferring a workpiece from a straightening jig to a sizing die. By simply pushing the work piece downward, the work piece can be smoothly removed from the correction jig without damaging the work piece.

According to a second aspect of the present invention, a ring made of an elastic body which is horizontally embedded in the inner peripheral surface of the jig body so as to be retractable and protrudes from the inner peripheral surface of the jig body in a natural state. The same effect can be obtained also by using the correction jig provided with.

[Brief description of drawings]

FIG. 1 is a perspective view of a sintered product and a correction jig which are works showing an embodiment of the present invention.

FIG. 2 is a perspective view of a turntable used for sizing.

FIG. 3 is a cross-sectional view showing a state in which a sintered product is supported by a straightening jig mounted on the turntable.

FIG. 4 is a cross-sectional view showing a state where sizing is performed by the same mold.

FIG. 5 is a sectional view of a straightening jig showing another embodiment of the present invention.

FIG. 6 is a perspective view of a sintered product.

FIG. 7 is a sectional view showing an example of a conventional technique.

[Explanation of symbols]

 21 Orthodontic jig 22 Jig body 25 Ball (supporting part) 41 Orthodontic jig 42 Jig body 44 O-ring (ring)

Claims (2)

[Claims] 1. A substantially cylindrical jig main body having an up-down direction as an axial direction, and a jig main body which is horizontally arranged at three or more places surrounding the center of the jig main body and is capable of projecting and retracting from an inner peripheral surface of the jig main body. A jig for straightening, comprising: and a supporting portion biased in a direction projecting from the inner peripheral surface. 2. A substantially cylindrical jig body having an up-down direction as an axial direction, and a jig body which is embedded horizontally and retractably in the inner circumferential surface of the jig body and projects from the inner circumferential surface of the jig body in a natural state. A jig for straightening, comprising a ring made of an elastic body.