JP2577098Y2 - Universal joint - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-speed universal joint for supplying a lubricant to a bearing inserted into a shaft of a cross shaft.

[0002]

2. Description of the Related Art In general, in a universal joint, each shaft portion of a cross shaft is supported by a pair of yokes via bearings. Usually, as the above-mentioned bearing, a needle roller bearing as a radial bearing and a thrust washer as a thrust bearing are used. The above-described needle roller bearing has a bearing cap which is inserted into a shaft end of a cross shaft to form an outer ring, and a needle roller which is interposed between an inner peripheral surface and a shaft end peripheral surface of the bearing cap. (Hereinafter referred to as a needle roller). The thrust washer is interposed between the end surface of the shaft end of the cross shaft and the inner end surface of the bearing cap.

In such a universal joint, a lubricant reservoir is provided at an intersection of the cross shafts, and a supply hole extending from the lubricant reservoir to the shaft end is provided. In some cases, the centrifugal force generated by the rotation of the universal joint supplies the thrust washer and the needle roller in the bearing cap through the supply hole. In this universal joint, an oil seal seals the space between the open end of the bearing cap and the peripheral surface of the shaft of the cross shaft.

[0004]

However, in the above-described universal joint, the oil seal is located at the end of the lubricant supply path, so that the pressure of the lubricant sent to the shaft end by centrifugal force causes The lubricant gradually leaks out from the oil seal and leaks, and there is a possibility that the lubricant may be insufficient at an early stage to cause poor lubrication. For this reason, it is necessary to frequently supply the lubricant to the lubricant reservoir, and there is a problem that maintenance is troublesome.

Further, in the above-mentioned universal joint, the lubricant around the thrust washer and the needle roller is provided for lubrication with little replacement, so that the entire lubricant filled in the lubricant reservoir is effectively used. Therefore, substantial deterioration of the lubricant occurs at an early stage, and therefore, the lubricant has to be filled more frequently, so that maintenance is more troublesome.

An object of the present invention is to solve the above-mentioned technical problems and to provide a universal joint which does not require frequent replenishment of a lubricant and is easy to maintain.

[0007]

In order to achieve the above object, a universal joint according to the present invention comprises a bearing fitted to each shaft portion of a cross shaft and a lubricant provided at a cross portion of the cross shaft. In a universal joint having a reservoir portion and a supply hole formed through each shaft portion of the cross shaft to supply the lubricant of the lubricant reservoir portion to the inside of the bearing, the lubricant inside the bearing is supplied to the cross shaft. A plane containing the axis of each shaft part of the cross shaft
Circulation path for circulating back to the lubricant reservoir portion via the oil passage that extends in a direction perpendicular is formed with, said cross shaft
Extends along a direction perpendicular to the plane containing the axis of each shaft
Install a check valve in the oil passage that opens only on the lubricant reservoir side.
During rotation, lubricant flows from the lubricant reservoir through the circulation path
And is circulated through the lubricant reservoir .

[0008]

According to the above construction, during operation of the universal joint, the lubrication of the lubricant reservoir is sent to the shaft end side of the cross shaft through the supply hole by the centrifugal force and supplied to the inside of the bearing. Is returned to the lubricant reservoir through the circulation path and the check valve, whereby the lubricant is circulated between the lubricant reservoir and the inside of the bearing. The entirety of the lubricant filled in the lubricant reservoir can be effectively used for lubrication of the bearing. In addition, since the lubricant is circulated, there is no end portion of the lubricant supply path. Therefore, it is possible to avoid the occurrence of lubricant leakage that has conventionally been caused by a high pressure at the end of the lubricant supply path.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic front view showing an embodiment of the universal joint of the present invention, and FIG. 2 is a longitudinal sectional view of the cross shaft. With reference to these drawings, this universal joint A includes a cross shaft 1, a bearing B inserted into an end of each shaft portion 1a of the cross shaft 1, and an opening side of a bearing cap 2 of the bearing B. An oil seal 12 for sealing between the end 2a and the shaft 1a, a lubricant reservoir 7 provided at an axis crossing portion 1b of the cross shaft 1, and a universal joint formed through each shaft 1a. The supply hole 8 for supplying the lubricant in the lubricant reservoir 7 to the bearing element in the bearing cap 2 by the centrifugal force caused by the rotation of A, and the supply hole 8 is provided in the supply hole 8 to transfer the lubricant from the lubricant reservoir 7 to the bearing element And a circulation path 10 for returning the lubricant used for lubricating the bearing elements in the bearing cap 2 to the lubricant reservoir 7.

The main part of the bearing B is constituted by the bearing cap 2, the thrust washer 5 and the needle roller 6 housed in the bearing cap 2. The bearing cap 2 has a substantially cylindrical shape with a closed head and an open bottom. Between the inner peripheral surface of the bearing cap 2 and the peripheral surface of the shaft portion 1a, a needle roller accommodating portion 4 comprising an annular space is provided.
Are formed, and the needle roller 6 is accommodated in the needle roller accommodating portion 4. Further, between the inner end surface of the bearing cap 2 and the end surface of the shaft portion 1a, a thrust washer housing portion 3 formed of a cylindrical space is formed, and the thrust washer 5 is housed in the thrust washer housing portion 3. I have. The thrust washer 5 has, on at least one surface, a plurality of grooves 5b for supplying lubricant, which extend radially from the center hole 5a. Further, a guide ring 11 having an L-shaped cross section is inserted into the bearing cap 2, and the guide ring 11 comes into contact with the outer peripheral portion of the thrust washer 5 and the end of the needle roller 6 to form a thrust washer. 5 and the movement of the needle roller 6 are regulated.

The oil seal 12 has a known structure that seals a space between a slinger 13 having a substantially L-shaped cross section press-fitted into the shaft portion 1a and an inner peripheral surface of the opening end of the bearing cap 2. A through hole 14 penetrating the shaft crossing portion 1b is provided in the shaft crossing portion 1b of the cross shaft 1, and an annular step portion 14a is formed at both ends of the through hole 14. The circulation path 10 is provided with the oil seal 1 in the needle roller housing 4.
It comprises a communication passage formed in the shaft portion 1a so as to communicate the vicinity of the portion 2 with the inside of the step portion 14a, and is connected to the lubricant reservoir 7 through a passage in a seal unit U2 described later. The lubricant reservoir 7 is provided at the step 1 of the through hole 14.
It is formed by closing both ends of the through hole 14 with a pair of seal units U1 and U2 arranged in 4a. These seal units U1 and U2 are fixed to the step portion 14a by a snap ring 40.

The seal unit U1 is housed in the main body 30 and the groove on the outer peripheral surface of the main body 30,
and an O-ring 31 for hermetically sealing between itself and the peripheral surface of FIG. The seal unit U <b> 2 is housed in the O-ring 31 that is housed in the main body 30 and the groove on the outer peripheral surface of the main body 30 and seals the space between the main body 30 and the peripheral surface of the step portion 14 a of the through hole 14, and is housed in the groove on the inner end surface of the main body 30. And an O-ring 32 for sealing between the end face of the step portion 14a and the body 30 and the O-ring 32
, A first axial path 34 for communicating a middle part of the radial path 33 to the outside, a screw plug 35 capable of opening and closing the first axial path 34, A second axial path 36 for communicating the end of the direction path 33 with the lubricant reservoir 7, a check valve 37 provided in the second axial path 36, and a central part of the main body 30. A third axial path 38 that communicates the lubricant reservoir 7 with the outside,
A nipple 39 for injecting a lubricant is provided at an end of the third axial path 38. The circulation path 10 includes:
Radial path 33, second axial path 3 of seal unit U1
6 and the check valve 37, the lubricant reservoir 7
Is communicated to. The needle roller accommodating portion 4 includes the circulation path 10, the radial path 33 in the seal unit U2, and the second path.
Is communicated with the lubricant reservoir 7 through the axial path 36. The check valve 37 functions as a one-way valve having an opening in the flow path of the lubricant and allowing the flow of the lubricant only in the direction from the second axial path 36 toward the lubricant reservoir 7. I have.

When adding additional lubricant,
With the screw plug 35 removed and the first axial path 34 open to the outside, new lubricant is injected into the lubricant reservoir 7 from the nipple 39 through the third axial path 38. The injected lubricant flows through the supply hole 8 to the thrust washer housing section 3 and the needle roller housing section 4, and the old lubricant remaining in the thrust washer housing section 3 and the needle roller housing section 4 is removed from the circulation path. 1
0, through the radial path 33 and the first axial path 34,
Released outside. In this way, the lubricant inside the cross shaft 1 can be completely replaced with a new one. The check valve 37 is connected to the radial path 3 from the circulation path 10.
The old lubricant sent to the third and second axial paths 36 exerts a predetermined resistance on the lubricant so as not to be sent to the lubricant reservoir 7 side.

The controller 9 controls the amount of the lubricant sent from the supply hole 8 to the thrust washer housing 3 by centrifugal force. According to this embodiment, when the universal joint A is rotated, the centrifugal force accompanying the rotation causes the lubricant in the lubricant reservoir 7 to be supplied through the supply hole 8 and the controller 9 to the thrust washer housing 3 and the needle. The lubricant is supplied to the roller accommodating portion 4 and is lubricated by the lubricant. The lubricated lubricant is returned to the lubricant reservoir 7 through the circulation path 10, the radial path 33 inside the seal unit U2, and the second axial path 36, whereby the lubricant reservoir 7 A lubricant can be circulated between the bearing cap 2 and the inside.

In the conventional case in which the circulation path 10 is not provided, the seal member is located at the terminal side in the lubricant feeding direction, and high pressure is applied to the seal member. In the present embodiment in which the lubricant is circulated, no high pressure is applied to the oil seal 3 and the lubricant does not leak from the oil seal 3, so that from the lubricant supply operation to the next lubricant supply operation Can be made longer. Moreover, the thrust washer accommodating section 3
The lubricant supplied in the lubrication in the needle roller accommodating portion 4 is sequentially replaced with the above-mentioned circulation, and the entire lubricant filled in the lubricant reservoir 7 can be used effectively. The lubricant supply interval can be made longer, making maintenance much easier.

Note that the present invention is not limited to the above-described embodiment. For example, the bearing B can be constituted by removing the thrust washer 5, and another known seal can be used instead of the oil seal 12. Various design changes can be made within a range that does not change the gist of the present invention, such as adopting a seal member.

[0017]

As described above, according to the universal joint of the present invention, the lubricant supplied from the lubricant reservoir to the interior of the bearing is returned to the lubricant reservoir through the circulation path to thereby store the lubricant. Since the lubricant can be circulated between the portion and the inside of the bearing, the entirety of the lubricant filled in the lubricant reservoir can be effectively used. Moreover,
Since the lubricant is circulated, no local high pressure is applied and no lubricant leakage occurs. Therefore, it is not necessary to perform the operation of replenishing the lubricant for a long period of time, so that there is an effect that the maintenance becomes very easy.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a universal joint according to an embodiment of the present invention.

FIG. 2 is a schematic plan view of a universal joint.

[Explanation of symbols]

 A Universal joint B Bearing 1 Cross shaft 1a Shaft 7 Lubricant reservoir 8 Supply hole 10 Circulation path 37 Check valve

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroyuki Ide 1-4-1 Meieki Station, Nakamura-ku, Nagoya Tokai Passenger Railway Co., Ltd. (56) References Real Opening Sho-51-150338 (JP, U) JP-A-61-19135 (JP, U) JP-A-45-9204 (JP, Y1) British Patent Application Publication No. 2032059 (GB, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16D 3 / 41 F16N 9/00 F16N 7/38-7/40

Claims (1)

(57) [Scope of request for utility model registration] 1. A bearing fitted to each shaft portion of a cross shaft, a lubricant reservoir provided at a cross portion of the cross shaft, and a lubricant reservoir formed through each shaft portion of the cross shaft. A universal joint having a supply hole for supplying a portion of lubricant to the inside of the bearing ;
A circulation path is formed to circulate back to the lubricant reservoir side through an oil path extending along a direction orthogonal to the plane including the line, and a plane including the axis of each shaft of the cross shaft; Along the orthogonal direction
A check valve that opens only on the lubricant reservoir side is provided in the oil passage extending
A universal joint characterized by being circulated to a lubricant reservoir through a circulation path .