JPH11285740A - Structure of rotary cam bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a rotary cam bearing excellent in productivity. SOLUTION: This structure of a rotary cam bearing comprises a first slide plate 11 having a recessed arched surface 11a attached to an inner surface 13 (13a-13c) of a cam housing 12 of a bearing member 10 and a second slide plate 21 attached to a rotary cam 20 and having a projecting arcuate surface 21a slidable in the peripheral direction of the arch on the arcuate surface 11a of the first slide plate 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cam bearing structure.

[0002]

2. Description of the Related Art It is known that a rotary cam is used for forming a negative angle on a work. For example,
JP-A-11089 discloses a rotary cam bearing structure having a cam housing 12 provided on a lower mold 10 and a rotary cam 20 rotatably inserted into the cam housing 12, as shown in FIGS. Is disclosed. The rotary cam 20 has a columnar shape having a substantially L-shaped notch 22, and one end of the notch 22 is a bent portion 23. The side surface 26 of the rotary cam 20 excluding the notch 22 is a continuous arc surface. The inner surface 13 forming the lower-type cam housing portion 12 is an arc surface having the same curvature as the arc surface of the rotating cam 20. The rotating cam 20 slides on the inner surface 13 of the cam housing portion 12 while sliding on the cam housing portion 12.
Rotates around the axis of rotation. Therefore, the rotating cam 2
0 and the inner surface 13 of the cam housing 12 are required to have high precision.

[0003]

However, the rotating cam 20
In addition, the respective arc surfaces of the inner surface 13 of the cam housing portion 12 are continuous, and a very large number of man-hours are required for accurate manufacturing. An object of the present invention is to provide a rotary cam bearing structure having excellent productivity by reducing the number of continuous arc surfaces as compared with the conventional case.

[0004]

The present invention to achieve the above object is as follows. (1) From a first slide plate having a concave arc surface and a second slide plate having a convex arc surface slidable in the arc circumferential direction on the arc surface of the first slide plate. A plurality of the first slide plates are attached to the inner surface of a bearing member having an inner surface forming a cam housing portion, and the plurality of second slide plates are separated from the inner surface of the bearing member to form the cam housing portion. The rotating cam bearing structure is attached to a side surface of a rotating cam disposed in the rotating cam bearing, and the arc surface of the first slide plate and the arc surface of the second slide plate are slidably in contact with each other. (2) a bearing member having an inner surface forming a cam housing portion, and an arc surface disposed on the cam housing portion of the bearing member and slidable on the inner surface of the cam housing portion on at least a part of the side surface; A rotating cam that is rotatable, and the distance from the rotation axis of the rotating cam to the inner surface of the bearing member is partially different, and the inner surface of the bearing member serving as a sliding surface of the rotating cam is A rotating cam bearing structure, wherein the rotating cam bearing structure is an arc surface or a flat surface having a curvature larger than that of the rotation cam.

In the rotary cam bearing structure of the above (1), a plurality of first slide plates having a concave arc surface attached to a bearing member having an inner surface forming a cam accommodating portion, and an inner surface in the cam accommodating portion. A plurality of second slide plates having a convex arc surface, which are attached to the side surface of the rotating cam disposed apart from the slidable contact,
It guides the rotation of the rotating cam in the cam housing. The arc surfaces of the first slide plate and the second slide plate are shorter than the continuous long arc surfaces found in the conventional rotary cam bearing structure, so that they can be easily manufactured. Therefore, it is excellent in productivity. The rotation of the rotary cam in the cam housing of the bearing member is due to the sliding contact between the first slide plate and the second slide plate, and the cam housing of the bearing member to which the first slide plate is attached. Since the inner surface of the rotary cam and the side surface of the rotary cam to which the second slide plate is attached do not make direct sliding contact, the inner surface of the rotary cam may not be a continuous arc surface with high precision as in the related art, but may be, for example, a flat surface.
Therefore, by adopting the rotary cam bearing structure of the above (1), the inner surface of the cam accommodating portion of the bearing member and the side surface of the rotary cam become easier to manufacture as compared with the related art. In the rotary cam bearing structure of the above (2), the rotary cam has an arc surface slidable on the inner surface of the cam housing portion on at least a part of its side surface, and the arc surface is slidable on the inner surface of the cam housing portion. Upon contact, the rotating cam rotates in the cam housing. The arc surface formed on the side surface of the rotary cam is at least a part of the side surface, and the distance from the rotary shaft center of the rotary cam to the inner surface of the bearing member is partially different, and a bearing member serving as a sliding surface of the rotary cam is provided. Since the inner surface of is an arc surface having a curvature larger than that of the rotating cam or a flat surface,
Compared with the continuous arc surface seen in the conventional rotary cam bearing structure, it can be easily manufactured and has excellent productivity.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary cam bearing structure according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2 show a first embodiment of the present invention, FIG. 3 shows a second embodiment of the present invention, FIG. 4 shows a third embodiment of the present invention, and FIG. 5 shows a fourth embodiment of the present invention. An example is shown. However, parts corresponding to the conventional structure are denoted by the same reference numerals as in FIGS. The rotary cam bearing structure according to all the embodiments of the present invention exemplifies a case where the rotary cam bearing structure is used for forming a negative angle of a workpiece.

Referring to FIGS. 1 and 6, a description will be given of a molding die used for molding a negative angle of a work, which is common to all embodiments of the present invention. The molding die has a bearing member (lower die) 10 and an upper die (see FIG. 6) 30. The upper die 30 includes a pad 31 and a suspension cam 33 having a bending blade 35 at a lower end. The bearing member 10 is provided with a cam housing (groove) 12 for opening the rotating cam 20 and opening upward. The cam housing 12 extends in the direction of the rotation axis of the rotation cam 20. One of the opening edges of the cam storage section 12 is a holding section 14 for holding a work. The rotary cam 20 has a substantially L-shaped notch 22. The notch 22 has a bent portion 23 for forming a product surface on one surface, and a slide plate 24 is attached to the other surface.

[0008] A method of forming a negative angle on a work using the above-described forming die will be described below. First, the work w is placed on the holding section 14 at the opening edge of the cam storage section 12 (see FIG. 6). Next, the upper die 30 is lowered, and the work w is held by the pad 31. At the same time, the shift bending blade 35 comes into contact with the slide plate 24, the rotary cam 20 rotates in the direction B, and the shift bending portion 23 of the rotary cam 20 contacts the work w (see FIG. 7). As the upper mold 30 continues to descend,
The shift bending blade 35 moves down the slide plate 24, and the work w
push. The work w is bent along the shift bending portion 23 of the rotary cam 20 to form a negative angle. After the negative angle is formed, the upper die 30 is raised, and the suspension cam 33 is moved to the slide plate 2.
Move away from 4. Thereby, the rotating cam 20 rotates in the direction A, and the bending portion 23 of the rotating cam 20 is separated from the work w, so that the work w can be easily removed from the forming die. As described above, the negative angle of the workpiece is formed by rotating the rotary cam 20 in the cam housing 12.

First, a first embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. The cam accommodating portion 12 provided in the bearing member 10 is, for example, a substantially quadrangular prism or a groove having an opening at an upper portion of a prism such as an approximately octagonal prism as shown in FIG. The inner surface 13 forming the part 12 includes a plurality of planes. The inner surface 13 may have a surface that is not machined, for example, a curved surface. The rotating cam (punch block) 20 may be a bar or a plate, and a prismatic member, a columnar member, or the like is used. In addition, the rotating cam 20 is disposed apart from the inner surface 13 of the cam housing 12.

A rotary cam bearing structure according to a first embodiment of the present invention, as shown in FIG.
And a second slide plate 21. The first slide plate 11 is a substantially plate-shaped member, and one side surface is a concave arc surface 11a. Second slide plate 2
Reference numeral 1 denotes a substantially plate-like member, one side surface of which is a convex arc surface 21a. The arc surface 21a is the first slide plate 11
Is slidable on the arc surface 11a in the circumferential direction of the arc. Therefore, the curvature of the arc surface 21a of the second slide plate 21 may be the same as the curvature of the arc surface 11a of the first slide plate 11, or may be smaller than the curvature of the arc surface 11a. 1 and 2 show an example in which the curvatures of the arc surface 21a and the arc surface 11a are the same.

The first slide plate 11 is attached by bolts 15 at intervals on a plurality of planes of an inner surface 13 including a plurality of planes forming the cam housing portion 12 of the bearing member 10. First slide plate 11
It is desirable that at least three of the cam storage units 12 be attached to three different planes on the inner surface 13. For example, as shown in FIG. 1, the bottom surface 13 a of the inner surface 13 forming the substantially octagonal column-shaped cam housing portion 12 and the bottom surface 13 a
The first slide plate 11 is attached to both left and right sides 13b and 13c extending perpendicular to a. The arc surface 11a of each first slide plate 11 has the same distance from the rotation axis of the rotation cam 20 disposed in the cam housing 12, and is on the same circumference.

A plurality of second slide plates 21 are attached to the side surface of the rotary cam 20 by bolts 25. The position where the second slide plate 21 is attached to the rotary cam 20 is a position facing the first slide plate 21 when the rotary cam 20 is arranged in the cam housing 12. Therefore, as shown in FIG. 1, when three first slide plates 11 are mounted, three second slide plates 21 are also mounted. The arc surfaces 21a of the second slide plates 21 attached to the rotary cams have the same distance from the rotation axis of the rotary cam 20 and are on the same circumference.

When the rotating cam 20 and the cam housing 12 extend in the direction of the rotating shaft, the rotating cam 20 may be bent by its own weight. Therefore, the plurality of first slide plates 11 are attached in parallel to, for example, the bottom surface 13a of the inner surface 13 of the cam housing 12 at intervals in the axial direction of the rotating cam, and the plurality of second slide plates 11 It is desirable to mount the rotating cam 20 so as to face the first slide plate 11 in the axial direction of the side surface of the rotating cam 20.

The first slide plate 11 and the second slide plate 21 may be provided with positioning holes for attaching to the bearing member 10 and the rotary cam 20.
The positioning hole is formed in a state where the first slide plate 11 and the second slide plate 21 are combined.
The first slide plate 11 and the second slide plate 21 have through holes penetrating therethrough. Each slide plate 1
When the positioning holes are provided in the first and the first 21, the pins are inserted into the positioning holes of the first slide plate 11 after the first slide plate 11 is attached to the bearing member 10. Then, the positioning holes of the second slide plate 21 are fitted to the pins, and the position of the second slide plate 21 with respect to the first slide plate 11 is determined. Thereby, the second slide plate 21
Is mounted on the side surface of the rotary cam 20 at a position facing the first slide plate. Further, in order to position the first slide plate 11 and the second slide plate 21, a groove may be provided in each of the bearing member 10 and the rotary cam 20, or a reference pin may be provided upright.

On the arc surfaces on which the first slide plate 11 and the second slide plate 21 slide, members having sliding performance generally used as bearing members are used. For example, the first slide plate 11 is made of gray cast iron, and the second slide plate 21 is made of S45C.
Made of wood.

Next, the operation of the first embodiment of the present invention will be described. A plurality of second slides are provided in the cam housing 12 of the bearing member 10 to which the plurality of first slide plates 11 are attached.
When the rotary cam 20 to which the first slide plate 21 is attached is disposed, each of the first slide plates 11
Arc surface 11a and arc surface 2 of each second slide plate 21
1a is in slidable contact. Thereby, the rotating cam 20 moves the first slide plate 11
, And is rotated by being guided by the second slide plate 21.

The arc surfaces 11a and 21a of the first slide plate 11 and the second slide plate 21 are longer in the circumferential and axial directions of the arc than the arc surfaces of the conventional rotary cam and the cam housing. short. Therefore, it is easy to obtain accuracy,
Manufacturing becomes easy. And since each plate can be mass-produced, the production cost can be reduced.

The first slide plate 11 is separate from the bearing member 10, and the second slide plate 21 is separate from the rotary cam 20. When the shape changes, only the slide plate whose shape has changed needs to be replaced with a new slide plate, so that maintenance is easy.

The first slide plate 11 and the second slide plate 11
Slide plate 21 during rotation of rotary cam 20,
Since many surfaces that are not in sliding contact with each other are obtained, even if dust or the like enters the sliding contact surface, the dust or the like is likely to fall out of the sliding contact surface.

If the arc surface 11a of the first slide plate 11 and the arc surface 21a of the second slide plate 21 have the same curvature and the entire arc surfaces can be in sliding contact with each other, the first Since the contact surface of the first slide plate 11 with the second slide plate 21 increases, the first slide plate 11 can withstand a high surface pressure. Therefore, galling and wear are less likely to occur. As the curvature 21a of the second slide plate 21 becomes smaller than the curvature of the arc surface 11a of the first slide plate 11, the contact area becomes smaller, so that the pressure resistance of the first slide plate becomes smaller.

Since the rotary cam 20 is guided by the first slide plate 11 and the second slide plate 21 in the cam housing 12 and rotates, the rotary cam 20 may have a prismatic shape as shown in FIG. Since the rotating cam 20 can use a member that has not been subjected to processing for increasing accuracy while maintaining the shape obtained by casting, the productivity is excellent. Further, even in the case where the finishing process is performed to increase the accuracy, if the rotating cam 20 is a prismatic member, the accuracy is more easily obtained and the processing is easier than the cylindrical member, so that the productivity is excellent.

Further, since the inner surface 13 of the cam accommodating portion 12 of the bearing member 10 includes a flat surface, the rotation cam 20 as in the prior art is used.
Compared to the inner surface consisting of a continuous arc surface with the same curvature as
It can be easily manufactured, and the bearing member 10 is excellent in productivity. Even if an arc surface is formed on the inner surface 13, the cam accommodating portion can be easily manufactured because high accuracy is not required as in the related art. In addition, if the bearing member 10 having the cam housing 12 and the lower die are integrated, the die rigidity is improved.

Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment of the present invention, as shown in FIG. 3, the rotating cam bearing structure is disposed on the bearing member 10 having the inner surface 13 forming the cam housing 12 and the cam housing 12 of the bearing member 10. A rotatable rotary cam 20 having an arc surface 21a slidable on the inner surface 13 of the cam housing 12 on a part of its side surface.

The cam accommodating portion 12 of the bearing member 10 has a substantially quadrangular prism shape and has an opening at an upper portion, and the inner surface 13 is formed of a plurality of flat surfaces. Therefore, the bearing member 1 is moved from the rotation axis of the rotation cam 20.
The distance to the inner surface 13 of the cam storage part 12 of 0 is partially different. (Conventionally, since the inner surface of the cam housing was a continuous arc surface having a constant curvature, the distance from the rotation axis of the rotary cam to the inner surface of the cam housing of the bearing member was fixed.)

The rotary cam 20 is formed of a rod-shaped member having a discontinuous arc surface 21a. Desirably, at least three discontinuous arc surfaces 21a are provided as shown in FIG. Each arc surface 21 a is on the same circle and serves as a sliding contact surface with the inner surface 13 of the bearing member 10. The circumferential length of the arc of the arc surface 21 a is adjusted according to the rotation angle of the rotary cam 20. The side surface of the rotary cam 20 excluding the arc surface 21 a does not make sliding contact with the inner surface 13 of the bearing member 10.

Next, the operation of the second embodiment of the present invention will be described. In the second embodiment of the present invention, the rotating cam 20 has the arc surface 21a slidably contacting the bearing member 10 at three locations in the circumferential direction of the arc at the same time, so that the inside of the cam accommodating portion 12 is stabilized around the rotation axis. Rotate. Arc surface 21a of rotary cam 20 and bearing member 10
The portion in contact with the inner surface 13 is a straight line extending in parallel with the rotation axis of the rotation cam 20. Since the inner surface 13 of the cam housing portion 12 of the bearing member 10 that is in sliding contact with the rotating cam 20 is flat, compared to a conventional case where an arc surface having the same curvature as the rotating cam 20 is continuously manufactured, as compared with the conventional case. Can be easily manufactured.
Therefore, the bearing member 10 is excellent in productivity. In addition, the rotary cam 20 has an arc surface only partially on a side surface, and can be manufactured more easily than a conventional rotary cam 20 having a continuous arc surface. The bearing member 10 having the cam housing 12
The rigidity of the mold is improved by integrating the and the lower mold.

Next, a third embodiment of the present invention will be described with reference to FIG. The rotary cam bearing structure according to the third embodiment of the present invention differs from the second embodiment in the planar shape of the inner surface 13 of the bearing member 10 and the shape of the rotary cam 20. In the third embodiment,
The inner surface 13 of the bearing member 10 has three flat surfaces as shown in FIG. Therefore, the distance from the rotation axis of the rotation cam 20 to the inner surface 13 of the cam housing 12 of the bearing member 10 is partially different. FIG. 4 shows the bearing member 10.
Although the convex surface formed integrally with the bearing member 10 is shown, the convex surface may be formed separately from the bearing member 10. Rotating cam 20
Uses a rod-shaped member having a continuous arc surface similar to that of a conventional rotary cam. The rotating cam 20 is brought into contact with the bearing member 10 at three locations in the circumferential direction of the arc so that the arc surface 21a comes into sliding contact with the bearing member 10.
2, so that it can rotate stably around the rotation axis. Further, as shown in the second embodiment, the rotating cam 20
Those having a discontinuous arc surface may be used.

Next, the operation of the third embodiment of the present invention will be described. In the third embodiment of the present invention, the rotating cam 20 has the arc surface 21a slidably contacting the convex front end surface 11a of the bearing member 10 at three points in the circumferential direction of the arc at the same time, and the rotating shaft 20 Stable rotation around the core. The contact portion between the arc surface 21a of the rotating cam 20 and the inner surface 13 of the bearing member 10 is a straight line extending parallel to the rotation axis of the rotating cam 20. Since the inner surface 13 of the bearing member 10 that is in sliding contact with the rotary cam 20 is flat, it can be manufactured more easily than in a conventional case where an arc surface having the same curvature as the rotary cam 20 is continuously formed. Therefore, the bearing member 10 is excellent in productivity. Also,
The rotation angle of the rotary cam 20 can be increased as compared with the rotary cam bearing structure of the second embodiment because the circumferential length of the arc of the arc surface is longer. In addition, by integrating the bearing member 10 having the cam accommodating portion 12 and the lower die, the rigidity of the die is improved.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The fourth embodiment of the present invention is different from the third embodiment in the shape of the front end surface of the convex surface of the inner surface 13 of the bearing member 10. The convex front end surface 11a of the inner surface 13 of the bearing member 10 of the fourth embodiment is a concave arc surface. Other portions of the inner surface 13 are flat. Therefore, the distance from the rotation axis of the rotation cam 20 to the inner surface 13 of the cam housing 12 of the bearing member 10 is partially different. FIG. 5 shows a convex surface formed integrally with the bearing member 10, but may be formed separately from the bearing member 10. The rotary cam 20 has an arc surface 21a slidable on the entire front surface 11a of the convex surface of the bearing member 10 entirely or partially on the side surface. The curvature of the arc surface 21 a of the rotary cam 20 is made smaller than the curvature of the convex end surface 11 a of the bearing member 10.

Next, the operation of the fourth embodiment of the present invention will be described. The curvature of the arc surface 21a of the rotary cam 20 is
When the curvature of the arc surface 11a of the inner surface 13 is smaller than that of the inner surface 13, the rotation surface of the rotary cam 20 is brought into sliding contact with the arc surface 11a of the bearing member 10 to rotate the cam housing. Therefore, for example, one type of bearing member 1 having an arc surface 11a having a predetermined curvature
For zero, a plurality of types of rotary cams 20 can be used as long as the curvature of the arc surface 21a is smaller than the predetermined curvature of the arc surface 11a of the bearing member 10. In that case, since only one kind of bearing member 10 needs to be manufactured,
The types of tools for manufacturing the arc surface may be small.

The inner surface 13 of the bearing member 10 at the portion that comes into sliding contact with the rotary cam 20 is an arc surface 11a.
Since the contact surface between the rotary cam 20 and the bearing member 10 is larger than that of the case where is a flat surface, the bearing member 10 can withstand a high load. In addition, by integrating the bearing member 10 having the cam accommodating portion 12 and the lower die, the rigidity of the die is improved.

[0032]

According to the rotary cam bearing structure of the first aspect,
The rotating cam is guided by a first slide plate attached to the side surface and a second slide plate attached to the inner surface of the bearing member, and rotates in the cam housing of the bearing member. The arc surface of each of the first slide plate and the second slide plate has a short length in the axial direction and the circumferential direction of the arc, so that manufacture is easy. Further, since the rotating cam and the bearing member do not need to have a continuous arc surface as in the related art, the rotating cam and the bearing member are also excellent in productivity. According to the rotating cam bearing structure of the second aspect, the inner surface of the bearing member is an arc surface having a curvature larger than the arc surface of the rotating cam or a flat surface, and a continuous surface having the same curvature as the rotating cam as in the related art. Since the arc surface need not be formed, the productivity is excellent. In particular, when the inner surface of the bearing member is a flat surface, the productivity is high because the manufacturing is easy. In addition, at least a part of the side surface of the rotary cam may be an arc surface, and the fewer the side surface is an arc surface, the better the productivity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a bearing member according to a first embodiment of the present invention in a state where a rotating cam is disposed in a cam housing portion.

FIG. 2 is a perspective view of the rotary cam bearing structure according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a state in which a rotating cam is arranged in a cam housing portion of a bearing member according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of a third embodiment of the present invention in which a rotary cam is disposed in a cam housing of a bearing member.

FIG. 5 is a sectional view of a contact portion between a rotating cam and a bearing member according to a fourth embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a state in which a rotating cam is arranged in a cam housing portion of a conventional bearing member.

FIG. 7 is a cross-sectional view showing a state in which a rotating cam is arranged in a cam housing portion of a conventional bearing member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Bearing member 11 1st slide plate 11a Arc surface 12 Cam accommodating part 13 Inner surface 20 Rotating cam 21 2nd slide plate 21a Arc surface

Claims (2)

[Claims] A first slide plate having a concave arc surface; a second slide plate having a convex arc surface slidable in the arc circumferential direction on the arc surface of the first slide plate; A plurality of the first slide plates are attached to the inner surface of a bearing member having an inner surface forming a cam housing,
A plurality of the second slide plates are attached to a side surface of a rotating cam disposed in the cam storage portion apart from an inner surface of the bearing member, and the arc surface of the first slide plate and the second slide plate are separated from each other. A rotary cam bearing structure in which an arc surface is slidably contacted. 2. A bearing member having an inner surface forming a cam housing portion, and an arc surface disposed on the cam housing portion of the bearing member and slidable on the inner surface of the cam housing portion on at least a part of the side surface. And
A rotating cam that is rotatable, and a distance from a rotation axis of the rotating cam to an inner surface of the bearing member is partially different, and an inner surface of the bearing member serving as a sliding surface of the rotating cam is A rotating cam bearing structure, wherein the rotating cam bearing structure is an arc surface or a flat surface having a curvature larger than that of the rotation cam.