JP6901242B2 - Power transmission mechanism with sliding constant velocity universal joint - Google Patents

Description

The present invention relates to a power transmission mechanism having a sliding constant velocity universal joint provided with a seal structure of a lubricant sealed inside the joint, which is used as a power transmission mechanism of various industrial machines such as steel equipment.

For example, as a power transmission mechanism of various industrial machines such as steel facilities, which coupling is used between the drive shaft and the driven shaft with a pair of shaft coupling portion. Conventionally, there is a shaft joint portion of this type using a sliding type double offset type (DOJ) (see, for example, Patent Document 1).

As shown in FIG. 4, the conventional power transmission mechanism of this type includes a structure in which a pair of shaft joint portions 111, 112 (sliding type constant velocity universal joint) are connected by a shaft 113. The main portion of each of the shaft joint portions 111 and 112 is composed of an outer joint member 114, an inner joint member 115, a ball 116 and a cage 117. In this power transmission mechanism , even if there is a misalignment between the pair of shaft joints 111 and 112, the rotational torque is transmitted at a constant speed between the drive shaft and the driven shaft.

In the outer joint member 114, linear track grooves 119 extending in the axial direction are formed at a plurality of locations on the inner peripheral surface 120 in the circumferential direction at equal intervals. In the inner joint member 115, linear track grooves 121 extending in the axial direction in pairs with the track grooves 119 of the outer joint member 114 are formed at a plurality of locations on the outer peripheral surface 122 in the circumferential direction at equal intervals.

The balls 116 are arranged between the track groove 119 of the outer joint member 114 and the track groove 121 of the inner joint member 115 to transmit rotational torque. The cage 117 is interposed between the inner peripheral surface 120 of the outer joint member 114 and the outer peripheral surface 122 of the inner joint member 115 to hold the ball 116.

In the constant velocity universal joint having the above configuration, as shown in FIG. 5, when a shaft misalignment occurs between the pair of shaft joint portions 111 and 112 and an operating angle is given, the inner joint member 115 and the outer joint member are provided. Rotational torque is transmitted to and from 114 via the ball 116 while allowing angular displacement and axial displacement. At this time, the internal component 118 including the inner joint member 115, the ball 116, and the cage 117 is slidable in the axial direction inside the outer joint member 114.

This constant velocity universal joint prevents leakage of lubricant 128 such as grease sealed inside the joint and prevents foreign matter such as dust and water from entering from the outside of the joint in the pair of shaft joint portions 111 and 112. It has a sealing structure for the purpose.

The seal structure is a rubber boot 131 having a large-diameter end portion 129 and a small-diameter end portion 130 and having a U-shaped folded shape in the middle, and is attached to an opening 132 of the outer joint member 114 in the axial direction. It is composed of a tubular metal fixing plate 133 overhanging. The boot 131 is mounted between the outer joint member 114 and the shaft 113 by fixing the large-diameter end portion 129 to the fixing plate 133 and fixing the small-diameter end portion 130 to the shaft 113.

Japanese Unexamined Patent Publication No. 2012-241882

By the way, in the conventional power transmission mechanism , by enclosing the lubricant 128 in the internal space p of the outer joint members 114 of the shaft joints 111 and 112, the shaft 113 takes an operating angle with respect to the outer joint member 114 and shafts. When the joint portions 111 and 112 rotate, the lubricity of the sliding portion inside the joint, that is, the sliding portion composed of the outer joint member 114, the inner joint member 115, the ball 116 and the cage 117 is ensured. I am doing it.

On the other hand, in this power transmission mechanism , when a shaft misalignment occurs between the pair of shaft joint portions 111 and 112 and an operating angle is given, the internal component 118 composed of the inner joint member 115, the ball 116 and the cage 117 is connected to the outer joint. It slides in the axial direction inside the member 114. When the internal component 118 slides, as shown in FIG. 5, the ball 116 of the shaft joint portion 111 located on the left side of the drawing abuts on the fixing plate 133, thereby restricting the axial displacement of the internal component 118 and the shaft 113. Will be done.

At this time, the lubricant 128 sealed in the internal space p of the outer joint member 114 flows out into the internal space q of the boot 131. Due to the outflow of the lubricant 128 into the internal space q of the boot 131, as shown in FIG. 6, the lubricant 128 pushes the boot 131 in the axial direction due to the action of centrifugal force due to high-speed rotation and inverts the boot 131.

In this way, rotational expansion occurs in the rubber boot 131 having low rigidity. As a result, the boot 131 may be damaged due to the occurrence of rotational expansion exceeding the plastic deformation of the boot 131.

Further, as described above, when the lubricant 128 easily flows out from the internal space p of the outer joint member 114 to the internal space q of the boot 131, the lubricant 128 existing in the internal space p of the outer joint member 114 is secured. In addition, it is necessary to enclose a large amount of the lubricant 128 in advance in the internal space p of the outer joint member 114. As a result, the amount of the lubricant 128 enclosed is increased.

Therefore, the present invention has been proposed in view of the above-mentioned improvements, and an object of the present invention is to prevent the lubricant from flowing out from the internal space of the outer joint member to the internal space of the boot, and to rotate the boot at high speed. It is an object of the present invention to provide a power transmission mechanism provided with a sliding constant velocity universal joint capable of improving performance.

The power transmission mechanism according to the present invention is an inner joint member that transmits torque between a bottomed tubular outer joint member and the outer joint member while allowing angular displacement and axial displacement via a torque transmission member. It is provided with a pair of shaft joint portions made of, and the inner joint member of the shaft joint portion is connected by a shaft member, and a boot is mounted between the outer joint member and the shaft member.

As a technical means for achieving the above-mentioned object, in the present invention, due to the axial displacement of the inner joint member, the torque transmission member and the inner joint member in one shaft joint portion do not protrude from the outer joint member, and the other. The displacement regulating portion that can come into contact with the bottom portion of the outer joint member in the shaft joint portion of the above is arranged so as to face the bottom portion of the outer joint member.

In the present invention, when the inner joint member is displaced in the axial direction, the displacement regulating portion provided in the other shaft joint member comes into contact with the bottom portion of the outer joint member to regulate the axial displacement of the inner joint member. Due to the regulation of axial displacement by the displacement regulating portion, the torque transmission member and the inner joint member in one of the shaft joint portions do not protrude from the outer joint member.

As described above, since the torque transmission member and the inner joint member do not protrude from the outer joint member, it is possible to prevent the lubricant sealed in the inner space of the outer joint member from flowing out into the inner space of the boot. As a result, it is possible to avoid rotational expansion in which the lubricant reverses the boot due to the action of centrifugal force due to high-speed rotation, so that damage to the boot can be prevented and the high-speed rotation performance of the boot can be improved.

The displacement regulating portion in the present invention preferably has a structure in which a plate having a convex portion that protrudes in the axial direction and has a convex portion that can come into contact with the bottom portion of the outer joint member is attached to an end portion of the shaft member that is exposed from the inner joint member.

If such a structure is adopted, when the inner joint member is displaced in the axial direction, the convex portion of the plate provided on the other axial joint member comes into contact with the bottom portion of the outer joint member, so that the inner side of the plate is formed by the convex portion. By restricting the axial displacement of the joint member, it becomes easy to prevent the torque transmission member and the inner joint member in one of the shaft joint portions from protruding from the outer joint member.

In the present invention, a structure in which the outer peripheral end portion of the plate is locked to the end surface of the inner joint member is desirable.

If such a structure is adopted, the shaft member can be prevented from coming off from the inner joint member by locking the outer peripheral end portion of the plate to the end surface of the inner joint member.

In the present invention, it is desirable to have a structure in which a partition plate for closing the opening of the outer joint member is arranged between the inner space of the outer joint member and the inner space of the boot.

If such a structure is adopted, the partition plate can surely prevent the lubricant sealed in the internal space of the outer joint member from flowing out into the internal space of the boot. As a result, the rotational expansion of the boot during high-speed rotation can be reliably avoided, so that the high-speed rotation performance of the boot can be further improved.

According to the present invention, when the inner joint member is displaced in the axial direction, the displacement regulating portion provided on the other shaft joint portion comes into contact with the bottom portion of the outer joint member, so that the axial direction of the inner joint member by the displacement regulating portion is provided. Due to the regulation of displacement, the torque transmission member and the inner joint member in one of the shaft joints do not protrude from the outer joint member. From this, it is possible to prevent the lubricant sealed in the internal space of the outer joint member from flowing out into the internal space of the boot. It is also possible to reduce the amount of lubricating material enclosed.

In addition, since the lubricant can avoid rotational expansion that reverses the boot due to the action of centrifugal force due to high-speed rotation, damage to the boot can be prevented and the high-speed rotation performance of the boot can be improved. As a result, the lubricity of the outer joint member in the internal space is improved, effective and stable sealing performance can be ensured for use at high speed rotation , and a sliding constant velocity universal joint having a long life and excellent durability is provided. A power transmission mechanism can be provided.

FIG. 5 is a cross-sectional view showing an overall configuration of a power transmission mechanism including a pair of shaft joints according to an embodiment of the present invention. It is sectional drawing which shows the state which took the operating angle by the shaft misalignment of a pair of shaft joints in the power transmission mechanism of FIG. (A) is a cross-sectional view showing the partition plate of FIG. 1, and (B) is a side view of (A). It is sectional drawing which shows the whole structure of the conventional power transmission mechanism. It is sectional drawing which shows the state which took the operating angle by the shaft misalignment of a pair of shaft joints in the power transmission mechanism of FIG. FIG. 5 is a cross-sectional view showing a state in which the boot is inverted at one of the shaft joints in the power transmission mechanism of FIG.

An embodiment of a power transmission mechanism having a sliding constant velocity universal joint according to the present invention will be described in detail below with reference to the drawings.

In this embodiment, for example, as a power transmission mechanism for various industrial machines such as steel equipment, a drive shaft and a driven shaft are connected via a sliding constant velocity universal joint (hereinafter, simply referred to as a constant velocity universal joint). Illustrate things. This power transmission mechanism is provided with a shaft joint consisting of a pair of constant velocity universal joints , and even if there is a misalignment between the pair of shaft joints, the rotational torque is constant between the drive shaft and the driven shaft. introduce.

In the following embodiment, the double offset type (DOJ), which is one of the sliding types that allow both angular displacement and axial displacement, is exemplified as the constant velocity universal joint, but the tripod is another sliding type. Type (TJ) and cross-groove type (LJ) constant velocity universal joints are also applicable.

FIG. 1 shows a power transmission mechanism in which the shaft joint portion has an operating angle of 0 °. The power transmission mechanism shown in the figure is composed of a pair of shaft joint portions 11 and 12 including a bottomed tubular outer joint member 14, an inner joint member 15, a ball 16 which is a torque transmission member, and a cage 17. A structure is provided in which a pair of shaft joint portions 11 and 12 are connected by a shaft 13 which is a shaft member. In each of the shaft joint portions 11 and 12, an internal component 18 composed of an inner joint member 15, a ball 16 and a cage 17 is housed in the internal space m of the outer joint member 14 so as to be slidable in the axial direction.

Regarding the outer joint member 14, the inner joint member 15, the ball 16 and the cage 17 constituting the pair of shaft joint portions 11 and 12, one shaft joint portion 11 (first shaft joint portion) and the other shaft joint portion 12 Since (the second shaft joint portion) has the same structure, one shaft joint portion 11 and the other shaft joint portion 12 are commonly described in detail below.

In the outer joint member 14, linear track grooves 19 extending in the axial direction are formed at a plurality of locations on the inner peripheral surface 20 in the circumferential direction at equal intervals. In the inner joint member 15, linear track grooves 21 extending in the axial direction in pairs with the track grooves 19 of the outer joint member 14 are formed at a plurality of locations on the outer peripheral surface 22 in the circumferential direction at equal intervals.

The balls 16 are arranged between the track groove 19 of the outer joint member 14 and the track groove 21 of the inner joint member 15 to transmit rotational torque. The number of balls 16 may be 6, 8, or other, and the number thereof is arbitrary. The cage 17 is interposed between the inner peripheral surface 20 of the outer joint member 14 and the outer peripheral surface 22 of the inner joint member 15 to hold the ball 16.

The outer joint member 14 has a tubular shape, and a flange 23 is integrally attached to an end portion located on the outer side in the axial direction by welding or the like. The flange 23 constitutes the bottom 24 of the outer joint member 14. The drive shaft and the driven shaft (not shown) are coaxially connected to the flange 23 by screwing or the like.

The shaft 13 is coupled to the inner joint member 15 so that torque can be transmitted by spline fitting by press-fitting into the shaft hole 25 of the inner joint member 15. The shaft 13 has a plate 27 attached to the shaft end portion 26 exposed from the shaft hole 25 of the inner joint member 15 by screwing.

In this way, the plate 27 is arranged to face the bottom 24 of the outer joint member 14. By locking the outer peripheral end portion 40 of the plate 27 to the inner end surface 41 of the inner joint member 15, the shaft 13 is prevented from coming off from the inner joint member 15.

In the power transmission mechanism having the above configuration, when a shaft misalignment occurs between the pair of shaft joint portions 11 and 12 and an operating angle (angle displacement of the shaft 13 with respect to the outer joint member 14) is given, the cage 17 holds the power transmission mechanism. The ball 16 is always maintained within the bisector of the operating angle at any operating angle, and the constant velocity of the joint is ensured.

In this power transmission mechanism , in both the shaft joint portions 11 and 12, the internal component 18 including the inner joint member 15, the ball 16 and the cage 17 can slide in the axial direction inside the outer joint member 14. When a shaft misalignment occurs between the pair of shaft joints 11 and 12 and an operating angle is given, the internal parts 18 of the shaft joints 11 and 12 slide in the axial direction, so that the pair of shaft joints 11 Allows axial displacement of the internal component 18 and shaft 13 between the parts 18 and 12.

In this constant velocity universal joint, by enclosing the lubricant 28 in the internal space m of the outer joint members 14 of the shaft joints 11 and 12, the shaft 13 takes an operating angle with respect to the outer joint member 14 and a pair of shafts. When the joint portions 11 and 12 rotate, the lubricity is ensured at the sliding portion inside the joint, that is, the sliding portion composed of the outer joint member 14, the inner joint member 15, the ball 16 and the cage 17. I am doing it.

This power transmission mechanism prevents leakage of the lubricant 28 such as grease sealed inside the joint and prevents foreign matter such as dust and water from entering from the outside of the joint in the pair of shaft joints 11 and 12. It has a seal structure of.

This seal structure is attached to a rubber boot 31 having a large-diameter end portion 29 and a small-diameter end portion 30 and having a U-shaped folded shape in the middle, and an opening 32 of the outer joint member 14 by screwing. It is composed of a metal fixing plate 33 having a tubular shape and protruding in the axial direction. As the material of the boot 31, various rubbers such as natural rubber, chloroprene rubber, nitrile rubber, and silicone rubber can be applied.

The boot 31 is an outer joint member by tightening and fixing the large-diameter end 29 to the outer peripheral surface of the fixing plate 33 with the boot band 34 and tightening and fixing the small-diameter end 30 to the outer peripheral surface of the shaft 13 with the boot band 35. It is mounted between the 14 and the shaft 13.

In the power transmission mechanism of the embodiment having the above configuration, as shown in FIG. 1, the outer joint protrudes in the axial direction from the outer end surface of each plate 27 for preventing the shaft 13 from coming off from the inner joint member 15. A convex portion 36, which is a displacement regulating portion that can come into contact with the bottom portion 24 of the member 14, is formed.

Here, as shown in FIG. 2, when a shaft misalignment occurs between the pair of shaft joint portions 11 and 12 and an operating angle is given, the internal component 18 of the shaft joint portions 11 and 12 slides in the axial direction. By doing so, the axial displacement of the internal component 18 and the shaft 13 is allowed between the pair of shaft joint portions 11 and 12. At this time, the convex portion 36 of the plate 27 in one of the shaft joint portions 12 (second shaft joint portion) located on the right side of the drawing abuts on the bottom portion 24 of the outer joint member 14, so that the internal component 18 is displaced in the axial direction. To regulate.

Due to the regulation of the axial displacement of the internal component 18 by the convex portion 36 of the plate 27, the internal component 18 in the other shaft joint portion 11 (first joint portion) located on the left side of the drawing, that is, the inner joint member 15, the ball. All 16 and the cage 17 are prevented from protruding from the opening 32 of the outer joint member 14.

The lubricant 28 sealed inside the outer joint member 14 exists in the internal space m including between the track groove 19 of the outer joint member 14 and the track groove 21 of the inner joint member 15. Therefore, since the internal component 18 does not protrude from the outer joint member 14, the lubricant 28 between the track grooves 19 and 21 is not pushed out by the ball 16 which is the internal component 18 due to the action of centrifugal force due to high-speed rotation. ..

Therefore, it is possible to prevent the lubricant 28 sealed in the internal space m of the outer joint member 14 from flowing out into the internal space n of the boot 31. As a result, the lubricant 28 can avoid rotational expansion that reverses the rubber boot 31 having low rigidity due to the action of centrifugal force due to high-speed rotation. In this way, by avoiding rotational expansion exceeding the plastic deformation of the boot 31, it is possible to prevent damage to the boot 31 and improve the high-speed rotational performance of the boot 31.

Further, since it is difficult for the lubricant 28 to flow out from the internal space m of the outer joint member 14 to the internal space n of the boot 31, it becomes easy to secure the lubricant 28 existing in the internal space m of the outer joint member 14. , The amount of the lubricating material 28 to be sealed in advance in the internal space m of the outer joint member 14 can be reduced.

As described above, since it is easy to secure the lubricant 28 in the internal space m of the outer joint member 14, the lubricity of the outer joint member 14 in the internal space m is improved, and the boot 31 that does not rotationally expand. As a result, it is possible to secure a stable sealing property that is effective for use at high speed rotation, and to provide a constant velocity universal joint having a long life and excellent durability.

Further, as shown in FIG. 1, this power transmission mechanism has a partition plate 37 that closes the opening 32 of the outer joint member 14 between the internal space m of the outer joint member 14 and the internal space n of the boot 31. It has an arranged structure. As shown in FIGS. 3A and 3B, the partition plate 37 has a through hole 38 through which the shaft 13 is inserted in the central portion, and a screw for attaching the fixing plate 33 to a plurality of locations in the circumferential direction of the peripheral portion. It has a shape in which a notch 39 is formed as an escape.

As shown in FIG. 1, the partition plate 37 is brought into contact with the opening 32 of the outer joint member 14, the partition plate 37 is covered with the fixing plate 33, and the partition plate 37 is fixed by screwing. In this way, by sandwiching the partition plate 37 between the opening 32 of the outer joint member 14 and the fixing plate 33, the partition plate 37 is formed between the internal space m of the outer joint member 14 and the internal space n of the boot 31. Deploy.

By adopting such a structure, as shown in FIG. 2, a shaft misalignment occurs between the pair of shaft joint portions 11 and 12, and an operating angle is imparted, so that the internal parts 18 of the shaft joint portions 11 and 12 are provided. With the partition plate 37, the lubricant 28 sealed in the internal space m of the outer joint member 14 in the shaft joint portion 11 located on the left side of the drawing flows out to the internal space n of the boot 31 when the lubricant 28 slides in the axial direction. You can definitely prevent that.

As a result, since the lubricant 28 does not exist in the internal space n of the boot 31, the rotational expansion of the boot 31 at the time of high-speed rotation can be reliably avoided, so that the high-speed rotation performance of the boot 31 can be further improved. Further, the amount of the lubricating material 28 to be sealed in advance in the internal space m of the outer joint member 14 can be significantly reduced.

The present invention is not limited to the above-described embodiments, and it goes without saying that the present invention can be carried out in various forms without departing from the gist of the present invention. Indicated by the scope of the claim and further includes the equal meaning described in the claims, and all modifications within the scope.

11, 12 Shaft joint 13 Shaft member (shaft)
14 Outer joint member 15 Inner joint member 16 Torque transmission member (ball)
24 Bottom 27 Plate 31 Boots 32 Opening 36 Displacement control part (convex part)
37 Partition plate m, n Internal space

Claims (4)

Through the first torque transmission member between the bottom portion and the first outer joint member having a bottomed tubular shape having an opening located on the opposite side in the axial direction from the bottom portion and the first outer joint member. A first shaft joint portion composed of a first inner joint member that transmits torque while allowing angular displacement and axial displacement, and a first shaft joint portion.
Through a second torque transmission member between the bottom portion and the second outer joint member having a bottomed tubular shape having an opening located on the opposite side in the axial direction from the bottom portion and the second outer joint member. It is provided with a second shaft joint portion composed of a second inner joint member that transmits torque while allowing angular displacement and axial displacement.
With the opening of the first outer joint member and the opening of the second outer joint member facing each other in the axial direction, the first inner joint member and the second inner joint member are attached to the shaft member. Boots are connected between the opening-side end of the first outer joint member and the shaft member, and between the open-side end of the second outer joint member and the shaft member, respectively. A power transmission mechanism with a sliding, constant-velocity joint that is mounted.
The first displacement restricting portion capable of contacting the bottom portion of the first outer joint member in the first shaft joint portion is arranged so as to face the bottom portion of the first outer joint member in the axial direction. When the bottom of the first outer joint member comes into contact with the first displacement regulating portion , the axial displacement of the first inner joint member to the bottom side of the first outer joint member is regulated. At the same time, the second torque transmission member and the second inner joint member in the second shaft joint portion are prevented from protruding from the second outer joint member.
The second displacement restricting portion of the second shaft joint portion that can come into contact with the bottom portion of the second outer joint member is arranged so as to face the bottom portion of the second outer joint member in the axial direction. When the bottom of the second outer joint member comes into contact with the second displacement regulating portion , the axial displacement of the second inner joint member to the bottom side of the second outer joint member is regulated. In addition, the first torque transmission member and the first inner joint member in the first shaft joint portion are prevented from protruding from the first outer joint member. Power transmission mechanism with fittings. In each of the pair of shaft joint portions, the displacement restricting portion exposes a plate having a convex portion that protrudes in the axial direction and can come into contact with the bottom portion of the outer joint member from the inner joint member at the end portion of the shaft member. The power transmission mechanism having the sliding type constant velocity universal joint according to claim 1, which has a structure attached to the above. The power transmission mechanism having a sliding constant velocity universal joint according to claim 2, wherein the outer peripheral end portion of the plate is locked to the end surface of the inner joint member in each of the pair of shaft joint portions. Claims 1 to 3 in which, in each of the pair of shaft joint portions, a partition plate for closing the opening of the outer joint member is arranged between the internal space of the outer joint member and the internal space of the boot. A power transmission mechanism having the sliding constant velocity universal joint according to any one of the items.

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