JP2008082395A - Grease filling method and grease filling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grease filling method and a grease filling device, capable of surely lubricating a needle bearing portion around a leg shaft with grease. <P>SOLUTION: When filling the grease G in the bearing portion interposed between the leg shaft 11 and a roller 7 mounted on the leg shaft 11, an area from the top end side of the leg shaft 11 to the peripheral surface of the roller 7 is covered by a cupped cover body 1 and an internal space of the cover body is closed by an elastic member that makes close contact with the roller. In the above state, the grease G is force-fed to the interior of the cover body 1 so as to lubricate the bearing portion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a grease filling method and a grease filling apparatus for a bearing portion disposed between a leg shaft of a tripod member or a bipod member of a constant velocity universal joint and a roller.

  When assembling a tripod type constant velocity universal joint used for a drive shaft or the like, the following steps are performed. First, the small-diameter boot band is inserted into the intermediate shaft of the drive shaft, the small-diameter portion of the boot is fixed to the intermediate shaft, and then the boot is filled with grease. Thereafter, a trunnion kit (consisting of a tripod member and a roller fitted on the leg shaft of the tripod member via a bearing such as a needle roller) is attached to the end of the intermediate shaft. Next, after filling the outer joint member with grease and assembling the outer joint member to the trunnion kit, the large diameter portion of the boot is fixed to the outer ring with the large diameter side boot band. This completes the assembly of the tripod constant velocity universal joint or drive shaft.

  Incidentally, a bearing portion such as a needle roller is interposed between the leg shaft of the trunnion kit and the roller for smooth rotation of the roller. If the bearing is poorly lubricated, an induced thrust is generated when the joint is operated, which adversely affects the NVH (noise, vibration, riding comfort) characteristics of the automobile.

  Therefore, conventionally, it has been proposed to infiltrate the lubricating oil in advance around the bearing portion of the leg shaft of the trunnion kit and assemble the trunnion kit to an outer joint member filled with grease (see Patent Documents 1 and 2). .

After assembling the trunnion kit in which the lubricant oil has been infiltrated around the bearing portion of the leg shaft in advance with the outer joint member filled with grease, slide the outer joint member manually to prevent the grease from being unevenly distributed. To make the grease spread and uniform.
Japanese Patent Laid-Open No. 11-063004 JP-A-11-270572

  When the above-mentioned grease is uniformly diffused, it is desirable that the grease is sufficiently infiltrated into the needle bearing portion of the trunnion kit in order to reduce the induced thrust and improve the joint life and durability. However, it is not possible to confirm whether the grease has surely infiltrated into the needle bearing portion around the leg shaft by manually sliding the outer joint member at the final assembly stage as in the prior art.

  In view of such a situation, the present invention provides a grease filling device capable of reliably infiltrating grease into a needle bearing portion around a leg shaft.

  The grease filling method according to the present invention is a grease filling method for filling a bearing portion interposed between a leg shaft of a tripod member or a bipod member and a roller mounted on the leg shaft, from the tip side of the leg shaft. Cover the roller surface with a cup-shaped cover, and with the elastic member in close contact with the roller closing the cover inner space, the grease is pumped into the cover inner space to apply grease to the bearing section. Infiltrate.

  According to the grease filling method of the present invention, grease can be filled inside the cover by pumping the grease into the space inside the cover. For this reason, if the grease filling is continued until the grease leaks to the outside from between the bearing portions, the bearing portion is completely infiltrated with the grease, which can be confirmed.

  The grease filling device of the present invention is a grease filling device for filling a bearing portion interposed between a leg shaft of a tripod member or a bipod member and a roller attached to the leg shaft, from the tip side of the leg shaft. An elastic member that includes a cup-shaped cover that can be crowned around the roller, and is provided with a nozzle structure for injecting grease into the cover, and closes the cover internal space in close contact with the roller Is provided on the cover peripheral wall.

  According to the grease filling device of the present invention, in the state where the tip of the leg shaft and the roller are covered with the cover, the inner space of the cover is closed by the elastic member. In this state, grease is injected through the nozzle structure and filled therein. For this reason, if the grease filling is continued until the grease leaks to the outside from between the bearing portions, the bearing portion is completely infiltrated with the grease, which can be confirmed.

  It is preferable that the grease ejection direction of the nozzle portion is a direction in which a rotational force is applied to the roller. Moreover, it is preferable to provide a detection means for detecting the number of rotations of the roller when the roller is rotated by applying a rotational force to the roller.

  According to the present invention, it is possible to confirm that the bearing portion is completely infiltrated with the grease by continuing to fill the grease until the grease leaks to the outside from between the bearing portions. For this reason, it is possible to prevent variation between products such as a drive shaft in which a constant velocity universal joint is assembled, and to reliably prevent generation of induced thrust due to poor lubrication of the bearing portion.

  In particular, if a rotational force is applied to the roller so that the roller rotates, the grease easily penetrates into the bearing portion, and it is possible to improve the prevention of induced thrust generation. Further, by rotating the roller, it is possible to detect an abnormality during rotation, and quality can be improved. Furthermore, the abnormality detection accuracy can be improved by detecting the number of rotations of the roller by the detecting means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an overall simplified view of the grease filling apparatus. The grease filling device fills a bearing portion of a tripod type constant velocity universal joint with grease, and includes a cover 1 (see FIG. 2 and the like) and a supply mechanism 2 for supplying grease into the cover 1. .

  As shown in FIG. 5, the tripod type constant velocity universal joint includes an outer ring 5 that is an outer joint member, a tripod member 6 that is an inner joint member, and a roller 7 that is a rolling element.

  The outer ring 5 has a bottomed cylindrical shape with one open end, and one end of a rotary shaft (not shown) (not shown) is connected to the center of the bottom. Three track grooves 8 extending in the axial direction are formed on the inner peripheral surface of the outer ring 5 at equal intervals in the circumferential direction. Each track groove 8 has a pair of roller guide surfaces 9 facing each other on both sides thereof. The roller guide surface 9 has an arc-shaped cross section and extends linearly in the axial direction of the outer ring 5.

  The tripod member 6 is formed by integrally forming three leg shafts 11 radially at equal intervals in the circumferential direction (120 ° intervals) on the outer peripheral surface of a cylindrical boss portion 10. The shaft end of the rotating shaft 12 (for example, a driven shaft) is connected to the shaft hole of the boss portion 10 by spline fitting. The tip end of each leg shaft 11 extends in the radial direction to the vicinity of the bottom surface of the track groove 8, and its outer peripheral surface is a cylindrical surface.

  The outer peripheral surface of the roller 7 has an arc shape in vertical section, and is configured to be in line contact with the roller guide surface 9. On the other hand, the inner peripheral surface of the roller 7 is formed in a cylindrical shape. Between the inner peripheral surface of the roller 7 and the outer peripheral surface of the leg shaft 11, a plurality of needle rollers 13 are disposed in a single row full roller state. The needle roller 13 is prevented from coming off by a retaining ring 15 while being sandwiched between washers 14 disposed at the root portion and the distal end portion of the leg shaft 11. Needle rollers 13 constitute a bearing portion.

  As shown in FIGS. 2 to 4, the cover 1 includes a main body 18 composed of a short cylindrical peripheral wall 16 and a wall 17 that closes one opening (upper opening) of the peripheral wall 16, and the inside of the main body 18. And a short cylindrical elastic member 20 attached to the inner peripheral surface 16 a of the peripheral wall 16 of the main body 18. The elastic member 20 is made of rubber, synthetic resin, or the like used for a sealing material or the like, and is disposed on the opening side of the main body 18.

  The nozzle structure 19 has a block body 22 having a hollow chamber 21, a connecting pipe 24 is connected to the block body 22, and the hollow chamber 21 and a communication hole 23 of the connecting pipe 24 are in communication. Further, as shown in FIG. 3, the block body 22 is provided with injection paths 25 arranged at a pitch of about 90 degrees along the circumferential direction. Each injection path 25 is inclined with respect to the axis of the cover 1 as shown in FIG. That is, one opening 25 a opens into the hollow chamber 21 and the other opening 25 b opens inside the cover 1. And the other opening part 25b has shifted | deviated to the clockwise direction with respect to one opening part 25a.

  Further, a bearing 26 is fitted into the wall 17 of the main body 18, and a connecting pipe 24 is fitted into the bearing 26. That is, a fitting hole 27 is provided in the wall 17 of the main body 18, and the bearing 26 is fitted in the fitting hole 27. For this reason, the main body 18 is provided and is rotatable around the axis O (see FIG. 2) of the cover 1.

  The cover 1 can cover the tip of the leg shaft 11 of the constant velocity universal joint and the roller 7 as shown in FIG. At this time, a slight gap is formed between the tip of the leg shaft 11 and the block body 22, and the outer peripheral surface 7 a of the roller 7 is in pressure contact with the inner peripheral surface 20 a of the elastic member 20. In the illustrated example, the outer peripheral surface 7 a of the roller 7 slightly bites into the inner peripheral surface 20 a of the elastic member 20. Due to the pressure contact between the outer peripheral surface 7 a of the roller 7 and the inner peripheral surface 20 a of the elastic member 20, the elastic member 20 acts as a seal member and the inside of the cover 1 is closed.

  The connecting pipe 24 is connected to the supply mechanism 2. The supply mechanism 2 includes a main body (mixing chamber) 30 that mixes breeze and air (air), and a grease supply passage 31 and an air passage 32 are connected to the main body 30. The main body 30 is provided with a trigger (not shown) for opening and closing the grease supply passage 31 and the air passage 32.

  That is, when the operator operates the trigger, the grease from the grease supply passage 31 can be supplied to the nozzle structure portion 19 via the connecting pipe 24 by air pressure. Thus, the trigger opens and closes the grease supply passage 31 and the air passage 32, and the interlocking mechanism with the valve mechanism of both passages is configured by an arbitrary system such as a mechanical system or an electrical system. In the case of the mechanical type, the valve mechanism is controlled by a mechanical mechanism to separate a certain amount of grease G, and then the grease G is pushed out with a set air pressure. In the case of the electric type, a certain amount of grease G is separated by using an electromagnetic valve, and then the grease G is pushed out with a set air pressure.

  Although not shown, the main body 30 is provided with a grease amount adjustment knob and an air pressure adjustment knob. By operating these knobs, the grease flow rate and the air flow rate are adjusted when the grease supply passage and the air passage are opened.

  By the way, the grease G pumped to the nozzle structure 19 is injected into the cover 1 through the injection paths 25 of the nozzle structure 19. At this time, in each ejection path 25, the other opening 25b is shifted in the clockwise direction with respect to one opening 25a. As a result, the roller 7 of the constant velocity universal joint rotates around the axis of the leg shaft 11. That is, the roller 7 rotates according to the reaction force that penetrates by injecting the grease G and the injection direction of the grease G.

  For this reason, this grease filling apparatus is provided with detection means for detecting the number of rotations of the roller 7. The detecting means can be composed of a magnetic encoder in which magnetic poles are alternately arranged in the circumferential direction and a sensor for detecting a magnetic pole change of the magnetic encoder. That is, the rotation speed is detected by attaching the magnetic encoder to the roller 7 side of the rotation side and attaching the sensor (rotation speed sensor) to the fixed side and detecting the magnetic pole change of the magnetic encoder accompanying the rotation of the roller 7. To do.

  Next, a grease filling method using the grease filling device will be described. First, the cover 1 is put on the leg shaft 11 and the roller 7 as shown in FIG. At this time, the elastic member 20 of the cover 1 is in close contact with the outer peripheral surface 7a of the roller 7 and sealed. The elastic member 20 also has an object of preventing damage to the outer peripheral surface of the roller 7.

  Thereafter, the trigger is operated to push the grease G in the grease supply passage into the cover 1 with air pressure. As a result, this air and grease G infiltrate the gap between the needle rollers 13, and excess grease G leaks out together with the air from the gap between the needle rollers 13. After confirming the overflow of the grease G, the finger is released from the trigger, and the grease filling operation is finished.

  By the way, the grease G is injected into the cover 1 through the injection path 25 of the nozzle structure 19. At this time, in each ejection path 25, the other opening 25b is shifted in the clockwise direction with respect to one opening 25a. As a result, the roller 7 of the constant velocity universal joint rotates around the axis of the leg shaft 11. That is, the roller 7 rotates according to the reaction force that penetrates by injecting the grease G and the injection direction of the grease G.

  When the roller 7 rotates, an abnormality during rotation is detected. In this detection, it is possible to determine the quality of the product by detecting rotational sound, rotational vibration, and the like. In addition, the rotation of the roller 7 facilitates the penetration of grease into the bearing portion.

  Further, since the grease filling apparatus includes the detection means, the number of rotations of the roller 7 is detected by the detection means. By this rotation speed detection (rotation speed detection), rotation abnormality detection can be detected with high accuracy. For example, when the pressure feeding force of the grease G is the same, the number of rotations (rotational speed) differs between normal rotation (normal rotation) and abnormal rotation. For this reason, the quality of the product can be determined.

  Thereafter, for the trunnion kit (comprising the tripod member 6 and the roller 7 fitted on the leg shaft 11 of the tripod member 6 via a bearing portion such as a needle roller 13) that has been filled with the grease G As in the conventional case, the outer joint member filled with grease is assembled. At this time, the outer joint member is moved back and forth lightly in the axial direction to evenly distribute the internal grease, and finally, the boot large-diameter portion is fixed to the outer peripheral surface of the outer joint member with a boot band. This completes a series of assembly steps.

  According to the present invention, it is possible to confirm that the bearing portion is completely infiltrated with the grease by continuing the filling of the grease G until the grease G leaks to the outside from between the bearing portions. For this reason, it is possible to prevent variation between products such as a drive shaft in which a constant velocity universal joint is assembled, and to reliably prevent generation of induced thrust due to poor lubrication of the bearing portion.

  In particular, if a rotational force is applied to the roller so that the roller rotates, the grease easily penetrates into the bearing portion, and it is possible to improve the prevention of induced thrust generation. Further, by rotating the roller, it is possible to detect an abnormality during rotation, and quality can be improved. Furthermore, the abnormality detection accuracy can be improved by detecting the number of rotations of the roller by the detecting means.

  As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the constant velocity universal joint is not limited to a single roller type, and is a double roller. It may be a type. Moreover, you may have a bipod member as a trunnion kit of a constant velocity universal joint. The inclination angle, diameter, number, and the like of the injection path 25 differ depending on the pressure feeding force of the grease G, the size of the constant velocity universal joint, etc., but depending on the injection of the grease G from the injection path 25 when the grease G is pumped. It can be arbitrarily changed within a range in which the roller 7 rotates. Furthermore, although the thickness and the axial length of the elastic member 20 vary depending on the material used, the elastic member 20 acts as a sealing material, and the roller 7 is given a rotational force by the injection of the grease G from the injection path 25. It can be arbitrarily changed within a range close to the roller 7 so that it can be applied.

  In addition, several types of covers 1 having different diameters are prepared, and the cover 1 having the optimum diameter for the constant velocity universal joint filled with the grease G can be selected. Further, if the cover 1 is connected to the main body 30 by screw connection or the like, it can be easily attached and detached.

It is a simplified diagram of a grease filling device showing an embodiment of the present invention. It is sectional drawing which shows the grease filling method using the said grease filling apparatus. It is a principal part cross-sectional top view of the said grease filling apparatus. It is the sectional view on the AA line of the said FIG. It is a cross-sectional view of a tripod type constant velocity universal joint.

Explanation of symbols

1 Cover 6 Tripod Member 7 Roller 11 Leg Shaft 19 Nozzle Structure

Claims (4)

In a grease filling method for filling a bearing portion interposed between a leg shaft of a tripod member or a bipod member and a roller attached to the leg shaft,
Covering from the tip end side of the leg shaft to the circumferential surface of the roller with a cup-shaped cover, and pressure-feeding grease to the cover internal space with the cover internal space closed by an elastic member in close contact with the roller The grease filling method is characterized in that grease is infiltrated into the bearing portion by the above. In a grease filling device for filling a bearing portion interposed between a leg shaft of a tripod member or a bipod member and a roller attached to the leg shaft,
A cup-shaped cover that can be crowned around the roller from the tip end side of the leg shaft is provided, and a nozzle structure for injecting grease into the cover is provided on the cover, and the roller is covered closely with the roller. A grease filling apparatus, characterized in that an elastic member for closing a body internal space is provided on a peripheral wall of a cover.   The grease filling device according to claim 2, wherein a grease ejection direction of the nozzle structure portion is a direction in which a rotational force is applied to the roller. 4. The grease filling apparatus according to claim 3, further comprising detection means for detecting the number of rotations of the roller.

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