JPH01255720A - Universal joint - Google Patents

Abstract

PURPOSE:To provide a universal joint having a specially high mechanical strength and a sufficiently durable torsional strength by providing a reinforcement in a part of each of the outer surface of thin wall parts of first and second shaft members. CONSTITUTION:After a spherical body 5 is fitted between arcuated surfaces 4, 4 of yoke parts of a first shaft member 2a, a second shaft member 2b is laterally slid in such a posture that its center axis is orthogonal to the axis of the first shaft member 2a, so as to fit its arcuated surfaces 4, 4 on the spherical body 5. Thereafter, both members 2a, 2b are extended on a straight line, and then are fitted thereon with a back-up ring 10 so as to assemble a universal joint. With this arrangement, the spherical body 5 is rotatably held at its outer peripheral surface on four sides which are set on two orthogonal lines crossing the four sides at the centers of the four sides, by the arcuated surfaces 4, 4 of the two members 2a, 2b in a line contact condition. Further, the back-up ring 10 as a reinforcement is attached so as to cover a part of each of the outer peripheral surfaces of thin wall parts of the members 2a, 2b, thereby it is possible to obtain a high strength.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a universal joint, and more specifically, the present invention relates to a universal joint, and more specifically, a first shaft member and a second shaft member each having a pair of yoke portions, as well as a first shaft edge member and a second shaft member. and a spherical body interposed between the shaft member and movably joined together, and a pedestal having a truncated conical portion is formed on opposing surfaces of the pair of yoke parts, The pedestal is formed such that the angle of the virtual apex of its conical shape is approximately 90', and the pedestals are arranged so that the imaginary classes [V] of the opposing pedestals are substantially in contact with each other. An arcuate surface is formed on the opposing surfaces, and this arcuate surface has a central axis in a direction transverse to the shaft member, and has approximately the same diameter as the sphere rotatably held between the arcuate surfaces. The present invention relates to a universal joint formed of a part of the circumferential surface of a virtual cylindrical body.

[Prior Art] Generally, a universal joint is connected to the yoke portions of a first shaft member and a second shaft member via a cross pin or a sphere, but in either case, the structure is complicated and the number of parts is large. processing,
Assembly work was complicated.

In particular, in order to obtain a high-quality universal joint, high machining accuracy is required for each component, and the work of assembling these components is difficult, leading to high costs.

In view of these circumstances, the present inventor previously proposed a universal joint as shown in Japanese Utility Model Application Publication No. 51-59744. In this invention, the ball receiving surface of the yoke part is formed with a recess along the spherical surface, so the yoke part must be pushed apart when fitting the sphere.

Therefore, when the yoke portion and the shaft member are integrally formed, the material needs to have appropriate elasticity. If a material such as plastic is used as such a material, although it may be sufficient for low torque applications, it is not suitable for high torque applications in terms of Rtfx. Therefore, for high torque applications, for example, as shown in Figure 4 of the same publication, the yoke part and the shaft member are constructed separately from metal materials, and after the sphere is assembled, a fixing member such as a screw is used to attach the yoke part and the shaft member. I tried to make it stick. Such methods are unsatisfactory in terms of simplifying assembly processing and reducing manufacturing costs.

Therefore, the inventor of the present invention constructed the shaft member into two halves along the axial direction, and combined these halves into a single body.

[Problems to be Solved by the Invention] The above configuration is certainly preferable because it makes it possible to simplify assembly processing and reduce manufacturing costs, but when used for high torque applications, There was a problem that the mechanical strength was insufficient, especially that it could not sufficiently withstand torsional stress.

It is an object of the present invention to provide a universal joint that eliminates the above-mentioned drawbacks of the prior art, is easy to manufacture and can sufficiently reduce costs, and has high mechanical strength, especially sufficient resistance to torsional strength. With the goal.

[Means for Solving the Problems] In order to achieve the above object, a universal joint according to the present invention includes a first shaft member and a second shaft member, each having a pair of yoke portions.
and a sphere that is interposed between the first shaft member and the second shaft member to movably join them, and has a truncated conical portion on opposing surfaces of the pair of yoke portions. A pedestal is formed, and the pedestal has a conical virtual apex formed at an angle of approximately 90°, and is arranged such that the virtual vertices of the opposing pedestals are substantially in contact with each other. An arcuate surface is formed on opposing surfaces of the pedestal, and the arcuate surface has a central axis in a direction transverse to the shaft member, and the pedestal is rotatably held between the arcuate surfaces. A universal joint formed of a part of the peripheral surface of a virtual cylindrical body having approximately the same diameter as the sphere, the universal joint covering a part of the outer peripheral surface of the thin-walled part of the first shaft member and the second shaft member. It is characterized by the fact that reinforcements are attached.

Furthermore, in order to facilitate manufacturing and reduce costs, the first shaft member and the second shaft member are formed by two halves of approximately the same shape along the axial direction so as to have respective cork portions. It is assumed that FFvl exists.

For the same purpose, the first shaft portion, the material, and the second shaft member may be formed by an injection molding powder method.

Preferably, the reinforcing member is a backup ring that covers the thin portions of the first shaft member and the second shaft member and has a thickness that is at least approximately the same as the thickness of the cylindrical portion of each of the shaft members.

Furthermore, for the same purpose, the reinforcing material may be ribs provided on the outer surfaces of the first shaft member and the second shaft member along their axial directions.

It is more preferable that the ribs are provided from the tips of the first shaft member and the second shaft member to the vicinity of the thin wall portion of the yoke portion.

[Operations and Effects] The functions and effects of the universal joint according to the present invention are as follows.

To connect each yoke part of the first shaft member and the second shaft member to the sphere, there is no need to use any coupling means such as drilling, caulking, or screwing, and the first shaft member and the second shaft member are connected to each other. It is easy to connect and assemble by simply setting the fitting angle of the members, and the first shaft member, second shaft member, and sphere are made of relatively simple members. Each member can be provided at low cost. Furthermore, the sphere and each shaft member are rotatably held by making line contact with the arcuate surface of each shaft member on the four outer peripheral surfaces that lie on two intersecting axes that intersect at right angles to the center of the sphere. Therefore, torque can be transmitted smoothly between both shafts even if the target tolerance is relatively high.
Coupled with the fact that there is no drilling or assembling of parts in the sphere or yoke, a reinforcing material is attached to the thin-walled outer peripheral surfaces of the first and second shaft members to cover part of their outer peripheries. It has high strength and can be used satisfactorily for high torque applications.

A simple structure can be achieved by using the reinforcing member as a backup ring that covers the thin parts of the first shaft member and the second shaft member and has a thickness that is at least approximately the same as the thickness of the cylindrical part of each of the shaft members. However, it is possible to make the entire joint sufficiently strong.

Furthermore, ribs provided on the outer surfaces of the first shaft member and the second shaft member along the axial direction thereof can also have sufficiently high strength. When the ribs are provided from the tips of the first shaft member and the second shaft member to the vicinity of the thin wall portion of the yoke portion, the thin wall portion of the shaft member can be reinforced even more strongly.

In addition, if each shaft member is configured by a combination of halves of approximately the same shape, each half, that is, each shaft member, can be manufactured using a method that is highly mass-producible by means such as forging or press working. , it becomes easy to reduce the price.

Furthermore, if the first shaft member, the second shaft member, and the halves of these shaft members are formed by the injection molding powder method, no material is wasted during molding, and the yield is extremely high. It is possible to realize productivity and reduce the price of the - layer.

[Embodiments] Next, embodiments of the universal joint according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the universal joint (A) according to the present invention has a first
A shaft member (2a), a second shaft member (2b), several-headed conical pedestals (3), (3) formed on mutually opposing surfaces of the pair of yoke portions (1), (1); , arcuate surfaces (4), (4) formed on opposing surfaces of these pedestals (3), (3), and these arcuate surfaces (4)
, (4), a sphere (5) rotatably held between;
Backup rings (10
).

As shown in FIG.
is formed so that the angle of the pedestals (3) and (3) is approximately 90 degrees, and the virtual vertices of the opposing pedestals (3) and (3) are approximately 90 degrees. (,) are arranged so that they are almost in contact with each other.

A pair of arcuate surfaces (4), (4) formed on the upper surface of each pedestal (3), (31) are connected to the double shaft member (2a).
, a virtual cylindrical body (b) having a central axis in a direction substantially orthogonal to (2b) and having the same diameter as the sphere (5).
It is formed along a part of the circumferential surface of.

The universal joint (phantom) configured in this way is assembled as shown in FIG.
(After fitting the sphere (5) between 41, slide the second shaft member (2b), which is the other shaft member, in the horizontal direction with its axis perpendicular to the first shaft member (2a) and fit the arcuate surfaces (4), (4) of the second shaft member (2b) into the sphere (5).Then, both shaft members (2a).

Stretch (2b) in the -straight direction and then fit the backup ring (10).

As a result, the sphere (5) has two points perpendicular to its center.
On the four outer peripheral surfaces on the intersection line of the book, the arcuate surfaces (4), (4) of the first shaft member (2a) and the arcuate surfaces (4), .:4) of the second shaft member (2b) are 2. ．． Thus, it is held rotatably through line contact. As a result, both shaft members (2a),
In (2b), separation in the axial direction is prevented by the intervention of method #C (5). Double shaft members (2a), (2b
) are linearly connected, as shown in FIG. Since they are in line contact, both connected shaft members (2a), (
2b) are prevented from shifting in a direction perpendicular to their axes, and as a result reliable torque transmission is achieved.

The arc surfaces (4), (4) are formed along a part of the circumferential surface of a virtual cylinder (b) having the same diameter as the sphere (5), but in this case, the sphere ( The virtual cylindrical body (b) may be formed halfway so that the sphere (5) can be held at the center. In this way, when fitting the sphere (5), the positioning of the sphere (5) will be difficult. As a result, assembly becomes easier and productivity is further improved.

Note that the backup ring (10) is attached to the shaft member (2a).
.

Various methods can be considered for fixing to (2b).

For example, a key groove may be formed in one or both of the two, and a key may be inserted into the key groove from the key provided on the other side or from the outside.

Furthermore, it is also possible to fix the contacting portions of the two by explosive welding.

It is preferable that the thickness of the backup ring (10) is approximately the same as the thickness of the cylindrical portion (21) of the shaft member, including the thickness of the thin wall portion (20) when the backup ring (10) is attached. The length of the ring (10) is sufficient as long as it can cover at least the outer peripheral surface of the thin-walled part;
It does not necessarily have to extend to the cylindrical end of the shaft member (the end opposite to the side into which the sphere (5) is fitted).

On the other hand, as a reinforcing material, as shown in FIGS. 5 and 6, ribs (11) are provided on the outer surfaces of the first shaft member (2a) and the second shaft member (2b) along their axial directions. Although the shape of the ribs is not limited, the ribs may have at least the first shaft member (2a) and the second shaft member (2a).
It is preferable that the yoke portion b) be provided from the tip to the vicinity of the thin wall portion (20) of the yoke portion (1).

In this way, the mechanical strength of the thin-walled portion can be effectively increased. The thickness of the rib may be such that the thickness of the thin portion is approximately the same as the thickness of the cylindrical portion (21) of the shaft member.

Furthermore, the shaft member and the reinforcing material may be manufactured by an injection molding powder method, and this method is as follows. First, raw materials such as stainless steel powder and a suitable binder are sufficiently kneaded to coat the stainless steel powder with the binder. Next, in order to facilitate supply to injection molding b1, this is granulated into pellets using a granulator. After heating, this pellet-shaped material is injection molded into a mold having a predetermined shape. This molded body is heated to an appropriate temperature, subjected to binder removal treatment, and then sintered.This sintering process causes 30 to 40% shrinkage, which is then molded into the final product. The large amount of shrinkage allows for high precision, dense structure, and extremely high strength. When shaft members and reinforcing materials are manufactured using this method, the yield is significantly higher than those manufactured by casting or press working.

In addition to the above-mentioned stainless steel powder, as raw materials, it is also possible to select ceramic powder, plastic powder, etc. depending on the purpose of the universal joint, and either of them can be molded with a high yield.

[Another embodiment] As shown in FIGS. 7 and 8 (only one of which is shown), the double shaft members (2a) and (2b) each have a yoke portion (1
), (1) may be formed by halves (2a+) and (2a2) that are divided into two along the axial direction. And each half (2a7)
.

By fitting the backup ring (10) into (2a2), it is possible to combine both halves (2a+) and (21LZ) and reinforce both shaft members (2a) and (2b).

In this way, when the double shaft members (2a) and (2b) are formed by a combination of halves (2a, ) and (2a2), they can be easily manufactured by means such as casting. Moreover, since both shaft members (2a) and (2b) have substantially the same shape, it is easy to mass-produce the -layer.

It can also be mass-produced at an extremely low cost by pressing metal plates or the like.

Further, it goes without saying that the halves of the double shaft member can be manufactured with good yield by the injection molding powder method as described above.

It should be noted that although numbers are written in the claims section for convenience of reference to the drawings, the present invention is not limited to the structure of the attached drawings by these entries.

[Brief explanation of the drawing]

The drawings show an embodiment of the universal joint according to the present invention, in which Fig. 1 is a sectional view, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is the universal joint shown in Fig. 1. 4 is a plan view showing the assembly procedure of the universal joint according to the present invention, FIG. 5 is a cross-sectional view of a universal joint using a reinforcing material of another embodiment, and FIG. 5 is a sectional view taken along the line Vl-vr in FIG. 5, FIG. 7 is an exploded sectional view of a first shaft member (second shaft member) of a universal joint according to another embodiment, and FIG. 8 is a first shaft member shown in FIG. 7. (The second shaft member) is an internal side plan view of a half body that constitutes the second shaft member. DESCRIPTION OF SYMBOLS 1... Yoke part, 2a... First shaft member, 2b... Second shaft member, 3... Pedestal, 4... Arc surface, 5... Sphere,
10...Reinforcement material, a...Virtual apex of cone, b...Virtual cylindrical body, 2a,
2a2 ・・・・・・Half body. Agent Patent Attorney Osamu Kitamura Figure 2 Figure 5 Figure 6 Procedures Amendment Book ■, Indication of Case 1988 Patent Application No. 80520 2, Title of Invention Universal Joint 3, Person Making Amendment Case and Relationships Patent Applicant Address 5-9-22 Yamatedai, Ibaraki City, Osaka Name Toshiharu Ida 4, Agent 5 Subject of amendment 6 Contents of amendment The scope of the patent claims will be corrected as shown in the attached sheet. 7. One document stating the scope of claims after the revision of the list of attached documents.Claim 1. Having a pair of yoke parts (1) and (1).
A shaft member (2a), a second shaft member (2b), and a sphere (5) that is interposed between the first shaft member (2a) and the second shaft member (2b) and movably joins them. and the pair of yoke parts (1). The opposing surface of (1) has a pedestal (
3) is formed, and the pedestal (3) has a conical virtual apex (a) formed at an angle of approximately 90°,
And each opposing pedestal (3). (3) are arranged so that the virtual vertices (a) and (a) are almost in contact with each other, and an arcuate surface (4) is formed on the opposing surface of the pedestal (3), This arcuate surface (4) is a virtual cylinder that extends along the central axis in a direction across the shaft member and has approximately the same diameter as the sphere (5) rotatably held between the arcuate surfaces (4). The universal joint is formed of a part of the circumferential surface of the body (b), and the thin wall portion (21) of the first shaft member (2a) and the second shaft member (2b)
) A universal joint characterized in that a reinforcing material (10) is attached to the outer circumferential surface thereof to cover a part of the outer circumference. 2. A substantially identical half body (2a = ), (
2. The universal joint according to claim 1, wherein the universal joint is formed by 2a2). 3. The reinforcing material is attached to the first shaft member (2a) and the second shaft member (2b
2. A hack-up ring having a thickness that is substantially the same as at least the thickness of the cylindrical portion (2o) of each of the shaft members (2a) and (2b) by covering the thin-walled portion (21) of the shaft member (2a) and (2b). Universal joint as described. 4. The reinforcing material is attached to the first shaft member (2a) and the second shaft member (2b
3. The universal joint according to claim 1, wherein the joint is a rib provided on the outer surface of the joint along the axial direction thereof. 5. The ribs are connected to the first shaft member (2a) and the second shaft member (2b
) The universal joint according to claim ↓, wherein the universal joint is provided from the tip of the yoke portion (1) to the vicinity of the thin wall portion (21) of the yoke portion (1). 6. The universal joint according to claim 1, wherein the first shaft member (2a) and the second shaft member (2b) are formed by an injection molding powder method. 7. The universal joint according to claim 2, wherein the halves (2a, ) and (2a2) constituting the first shaft member (2a) and the second shaft member (2b) are formed by an injection molding powder method. .

Claims (1)

[Scope of Claims] 1. A first shaft member (2a) and a second shaft member (2b) having a pair of yoke portions (1), (1), and a first shaft member (2a) and a second shaft member (2b); It consists of a sphere (5) that is interposed between the shaft member (2b) and movably joins the two, and a truncated cone is formed on the opposing surfaces of the pair of yoke parts (1), (1). A pedestal (3) having a shaped part is formed,
The pedestal (3) has a conical virtual apex (a) formed at an angle of approximately 90°, and each of the opposing pedestals (
3), the virtual vertices (a) of (3) are arranged so that they are almost in contact with each other, and an arcuate surface (4) is formed on the opposing surface of the pedestal (3). and this arcuate surface (4) has a central axis in a direction crossing the shaft member,
and a virtual cylindrical body (b) having approximately the same diameter as the sphere (5), which is rotatably held between the circular arc surfaces (4).
The universal joint is formed by a part of the circumferential surface of the first shaft member (2a) and the second shaft member (2b).
1) A universal joint characterized in that a reinforcing material (10) is attached to the outer circumferential surface to cover a part of the outer circumference. 2. A substantially identical half body (2a_1) in which the first shaft member (2a) and the second shaft member (2b) are divided into two along the axial direction so as to have respective yoke portions (1), (1). , (2a_2)
2. The universal joint according to claim 1, wherein the universal joint is formed by: 3. The reinforcing material is attached to the first shaft member (2a) and the second shaft member (2b
3. The backup ring according to claim 1 or 2, wherein the backup ring has a thickness that is substantially the same as at least the thickness of the cylindrical portion (20) of each of the shaft members (2a), (2b) by covering the thin wall portion (21) of the shaft member (2a), (2b). universal joint. 4. The reinforcing material is attached to the first shaft member (2a) and the second shaft member (2b
3. The universal joint according to claim 1, wherein the joint is a rib provided on the outer surface of the joint along the axial direction thereof. 5. The ribs are connected to the first shaft member (2a) and the second shaft member (2b)
4. The universal joint according to claim 3, wherein the universal joint is provided from the tip of the yoke portion to the vicinity of the thin wall portion (21) of the yoke portion (1). 6. The universal joint according to claim 1, wherein the first shaft member (2a) and the second shaft member (2b) are formed by an injection molding powder method. 7. The universal joint according to claim 2, wherein the halves (2a_1) and (2a_2) constituting the first shaft member (2a) and the second shaft member (2b) are formed by an injection molding powder method.