JP2006275195A - Propeller shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To always surely secure ventilation inside and outside of boots, by returning grease in a ventilation groove inside the boots, by using centrifugal force. <P>SOLUTION: The boots 10 for blocking up an end part of a constant velocity universal joint 4, are installed by straddling one shaft and the other shaft 3, and a boots cover 16 is arranged on the end surface side of the boots. The ventilation groove 14 is formed in the shaft direction on an inner peripheral surface of a cylindrical wall 12 of the boots, and a bottom surface 14a of the ventilation groove is slantingly formed in the outer peripheral direction over the inner edge on the boots inner side from the outer edge on the boots cover side. Thus, the grease in the ventilation groove is returned inside along the bottom surface by using the centrifugal force. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle propeller shaft, and more particularly to a structure of a boot that covers a constant velocity joint provided in the middle of the propeller shaft.

  As a propeller shaft of this type of vehicle, one described in Patent Document 1 below is known.

  In this propeller shaft, a drive shaft connected to the transmission side of the vehicle and a driven shaft connected to the differential gear side are connected to each other via a joint mechanism having a torque transmission ball, and the end of the joint mechanism is closed. Thus, the boot is attached and fixed across the two shafts, and the inner space closed by the boot is filled with grease for lubrication.

  The boot mounting portion with respect to the driven shaft is constituted by a cylindrical wall, and a ventilation groove for releasing pressure in the boot due to thermal expansion or the like is formed on the inner peripheral surface of the cylindrical wall.

Furthermore, since the outer end side of the ventilation groove is open to the outside as it is, water drops and dust can easily enter the boot, so that the driven shaft side extends from the end surface of the cylindrical wall of the boot to the outer peripheral area. A boot cover is attached.
JP 2004-245354 A

  However, in this conventional propeller shaft, as described above, since the grease is filled in the inner space of the boot, the grease is clogged in the ventilation groove during operation of the constant velocity joint. There is. If it does so, it will become difficult to exhaust the pressure air in boots outside from a ventilation groove.

  As a result, there is a concern that the boot may be irregularly greatly deformed due to a pressure change in the boot, resulting in a decrease in durability.

  Therefore, the present invention is intended to provide a propeller shaft that can always reliably ensure ventilation inside and outside the boot.

  In order to solve the above-described problem, the invention described in claim 1 is a joint mechanism that transmits a rotational force from a drive shaft member to a driven shaft member, and one end attached to the drive shaft member of the joint mechanism. An end is attached to the driven shaft member to cover the outer periphery of the joint mechanism, and a boot filled with lubricating grease of the joint mechanism is connected to the inside and outside of the boot mechanism, and is inclined to the outer peripheral side. And a ventilation passage having an inclined portion.

  For example, as is well known, a centrifugal force acts on a propeller shaft of a vehicle by rotating at a high speed, and the present invention uses this centrifugal force to eliminate grease in the ventilation passage. It is.

  In other words, when the boot is deformed by centrifugal force and the lubricating grease prefilled inside enters the ventilation passage, the grease flows along the inclined portion by the centrifugal force. Eliminated from within. For this reason, the ventilation passage always has good air permeability.

  According to a second aspect of the present invention, there is provided a joint mechanism for transmitting rotational force from the drive shaft member to the driven shaft member, one end attached to the drive shaft member of the joint mechanism, and the other end attached to the driven shaft member. Covering the outer periphery of the joint mechanism, and formed on a fixed-side inner peripheral surface at least on the one end side of the boot, and a boot made of silicon rubber filled with lubricating grease for the joint mechanism on the inside, And a ventilation passage communicating with the inside and outside of the boot, wherein the ventilation passage is formed so as to be inclined toward the outer peripheral side by deformation due to the centrifugal force of the boot.

  Since the molding material of the boot is molded with soft silicone rubber against a relatively hard rubber that is a general molding material of boots, the boot is deformed by centrifugal force as the propeller shaft rotates, The ventilation passage is deformed to be inclined so that the outer peripheral side, that is, the inside of the boot is high and the outside is low.

  Therefore, the lubricating grease that has entered the ventilation passage is returned to the inside of the boot along the inclined surface of the ventilation passage by the centrifugal force. Therefore, it is possible to prevent the grease from leaking or scattering to the outside, and to improve the air permeability of the ventilation passage at all times.

  According to a third aspect of the present invention, there is provided a joint mechanism for transmitting rotational force from the drive shaft member to the driven shaft member, one end attached to the drive shaft member of the joint mechanism, and the other end attached to the driven shaft member. And the outer periphery of the joint mechanism is formed on the inner side of the boot, the inner side of the boot being filled with the grease for lubrication of the joint mechanism, and at least one end of the boot. A vent passage communicating with the boot and a boot cover provided on an outer periphery of the boot at least forming the vent passage of the boot, wherein the boot is formed of a material that can be deformed by centrifugal force, and the boot cover is formed of the boot It is characterized by being molded from a material having higher rigidity.

  According to this invention, the boot is deformed so that the ventilation passage is inclined toward the outer peripheral side by being bent and deformed to the outer peripheral side due to the influence of the centrifugal force accompanying the rotation. The amount of deformation is regulated. As a result, excessive deformation of the boot can be prevented.

  Hereinafter, each embodiment of the propeller shaft according to the present invention will be described in detail with reference to the drawings. In each embodiment, the propeller shaft is applied to a vehicle.

  FIG. 2 shows a first embodiment of the propeller shaft according to the present invention. The propeller shaft 1 includes a drive shaft (not shown) which is a drive shaft member connected to the transmission side, and one end portion via a cardan joint 2. A driven shaft 3 that is a driven shaft member connected to the drive wheel side and a constant velocity joint 4 that is a joint mechanism that connects the drive shaft and the driven shaft 3 to each other are provided.

  In the drive shaft, a holding portion 5 constituting an outer race of the constant velocity joint 4 is integrally provided at the rear end of the shaft main body portion, and the driven shaft 3 is a small-diameter stub shaft inserted and arranged inside the holding portion 5. 6 is integrally provided at the front end of the shaft main body.

  The constant velocity joint 4 includes an outer race formed by the holding portion 5, an annular inner race 7 provided on the outer periphery of the distal end portion of the stub shaft 6, and a rolling motion between the inner race 7 and the holding portion 5. A plurality of torque transmission balls 8 provided freely and a cage 9 for holding the torque transmission balls 8 are provided.

  A rubber boot 10 is attached between the holding portion 5 and the stub shaft 6, and the open end of the constant velocity joint 4 is sealed with the boot 10. Further, the constant velocity joint 4 is filled with lubricating oil such as grease, and the outflow of the lubricating oil is prevented by the boot 10.

  The boot 10 is integrally formed of flexible silicone rubber, and as shown in FIG. 1, the boot 10 is formed in a cylindrical shape in which a half section along the axial direction forms a substantially U-shape, that is, from the central portion 10 a to the outer peripheral side. The large-diameter end portion 10b is formed in a folded shape, and is fixed to the holding portion 5 via a metal cylindrical boot adapter 11. The outer peripheral end of the large-diameter end portion 10b is fixed by tightening the free end portion 11a of the boot adapter 11, while the small-diameter end portion 10c on the inner peripheral side is integrally formed with the cylindrical wall 12 at the tip portion. The tubular wall 12 is formed and fastened to the outer peripheral surface of the stub shaft 6 by a boot band 13. The base end portion of the boot adapter 11 is fixed to the outer peripheral surface of one end portion of the holding portion 5 by caulking.

  Further, a ventilation groove 14 is formed on the inner peripheral surface of the cylindrical wall 12 as a ventilation passage continuing from one end to the other end in the axial direction. The ventilation groove 14 has a bottom surface 14a formed in a substantially arcuate cross-sectional shape and a uniform overall cross-sectional area, and the cylindrical wall 12 and the stub shaft 6 fastened by the boot band 13. An air vent passage communicating the inside and outside of the boot 10 is formed between the two.

  Further, as shown in FIG. 1, a radial groove 15 is formed on the distal end surface of the cylindrical wall 12 to connect the end of the ventilation groove 14 to the outer periphery of the cylindrical wall 12.

  A rubber boot cover 16 is attached to the stub shaft 6 so as to cover from the front end surface of the cylindrical wall 12 of the boot 10 to the outer peripheral area. The boot cover 16 is integrally formed of a general chloroprene rubber having a hardness higher than that of the silicone rubber of the boot 10, and is fitted and fixed to the annular groove 6a of the stub shaft 6, and the mounting base 16a A cover cylindrical portion 16b that expands in a step shape and covers the outer peripheral surface of the cylindrical wall 12 in a non-contact state, and a root portion on the cylindrical wall 12 side of the boot 10 that extends from the tip of the cover cylindrical portion 16b A lip portion 16c that contacts the vicinity is formed, and a ventilation groove 17 is formed on the inner peripheral surface of the tip portion of the lip portion 16c so as to communicate the space portion on the outer peripheral side of the cylindrical wall 12 to the outside of the boot cover 16.

  Therefore, according to this embodiment, since the molding material of the boot 10 is molded of soft silicon rubber, when the propeller shaft 1 is rotationally driven during traveling of the vehicle, the boot 10 is as shown in FIGS. 3 and 4. The outer wall is bent and deformed by the rotational centrifugal force, and further bent and deformed outward as the centrifugal force increases. In particular, the cylindrical wall 12 is outwardly deformed by the outward bending of the small-diameter end portion 10c. Therefore, the vent groove 14 is inclined and deformed so that the bottom surface 14a thereof is inclined to the outer peripheral side, that is, the inner side of the boot 10 is sufficiently higher from the distal end side of the cylindrical wall 12. .

  Therefore, the grease that has entered the ventilation groove 14 is returned to the inside of the boot 10 along the inclined bottom surface 14a of the ventilation groove 14 by the centrifugal force. Accordingly, it is possible to reliably prevent the grease from being discharged or scattered to the outside and to obtain a good air permeability at all times.

  In addition, since the boot cover 16 is made of chloroprene rubber that is harder than the boot 14 and has high rigidity, the boot 10 is bent outward due to the influence of centrifugal force as described above. When it is deformed and bent more than a predetermined amount, the amount of deformation can be regulated by the lip portion 16c of the boot cover 16. As a result, it is possible to prevent the boot 10 from being excessively bent and deformed outward.

  Therefore, since excessive deformation of the boot 10 is restricted, deformation interference with the free end portion 11a of the boot adapter 11 due to large bending of the central portion 10a and large deformation of the small-diameter end portion 10c is eliminated. It is possible to improve the durability.

  Further, since excessive deformation of the boot 10 can be restricted by the boot cover 16, there is no need to change the structure, and an increase in the number of parts can be prevented. Therefore, an increase in manufacturing cost can be suppressed.

  FIG. 5 shows a second embodiment of the present invention, in which the boot 10 is formed of hard chloroprene rubber like the boot cover 16. The ventilation groove 14 has a bottom surface 14a (inclined portion) formed so as to be inclined upward from the distal end side of the cylindrical wall 12 along the inner side of the boot 10 with a slight angle.

  Therefore, when the propeller shaft 1 is rotationally driven during traveling of the vehicle, if the grease previously filled in the boot 10 enters the ventilation groove 14, the grease is caused by the centrifugal force. The inside of the boot 10 is returned from the inside of the ventilation groove 14 along the inclined bottom surface 14 a of the ventilation groove 14. For this reason, the grease inside the boot 10 is not discharged to the outside, and it is possible to ensure good ventilation of the ventilation groove 14 at all times.

  The boot 10 is made of hard chloroprene and has a relatively high overall rigidity. Therefore, the boot 10 is not greatly bent outward by the centrifugal force, but is slightly bent by the large centrifugal force. In the case of deformation, the small-diameter end portion 10c side is deformed outward, so that the inside of the ventilation groove 14 is pulled up and the inclination angle of the bottom surface 14a is further increased. It becomes possible to return to the inside.

  FIG. 6 shows a third embodiment, in which the boot 10 is made of silicon rubber as in the first embodiment, while the boot cover 16 is made of chloroprene rubber. In addition, the ventilation groove 14 is formed in a structure having a substantially uniform cross section as in the first embodiment.

  A reinforcing band 18, which is a metal cylindrical reinforcing member, is attached to the outer peripheral surface of the cover cylindrical portion 16 b of the boot cover 16 in a wound state.

  Therefore, according to this embodiment, since the boot cover 16 is reliably restrained from being deformed outward by the reinforcing band 18, the boot 10 is externally influenced by the centrifugal force as shown in FIG. Even if it is bent and deformed in the direction, the lip portion 16c can surely prevent the boot 10 from being excessively bent and deformed. Thereby, the durability of the boot 10 is improved.

  Further, when the boot 10 is slightly bent outward and deformed by centrifugal force, the bottom surface 14a of the ventilation groove 14 is formed in an upwardly inclined shape toward the inside as shown in FIG. It is effectively returned to the inside along the inclined bottom surface 14a. Therefore, it is not discharged to the outside.

  FIG. 7 shows a fourth embodiment, and the rubber material of the boot 10 and the boot cover 16 is the same as that of the first embodiment, but the cover cylindrical portion 16b of the boot cover 16 is replaced with the small diameter end portion 10c of the boot 10. Therefore, the lip portion 16c is in contact with the outer peripheral surface of the small-diameter end portion 10c at the substantially central position.

  Therefore, according to this embodiment, when the boot 10 is bent and deformed outward by the centrifugal force, the lip portion 16c of the boot cover 16 supports the substantially center position of the small diameter end portion 10c from the outside. The bending deformation can be effectively controlled. Thereby, the durability of the boot 10 is improved.

  FIG. 8 shows a fifth embodiment in which the structure of the ventilation passage is changed, and a ventilation hole 20 which is a ventilation passage is formed at a substantially central position of an end wall 19 provided on the drive shaft side of the holding portion 5. Has been. The vent hole 20 is formed in a conical shape in which an inner peripheral surface 20a is formed in an expanded shape at a predetermined angle from the outside toward the inside.

  Therefore, according to this embodiment, when the grease filled in the constant velocity joint 4 enters the vent hole 20, the grease is returned to the inside along the inclined inner peripheral surface 20a of the vent hole 20 by centrifugal force. It is. Accordingly, the grease is not discharged to the outside of the constant velocity joint 4 and it is possible to ensure good air permeability of the vent hole 20 at all times.

  The technical ideas other than the invention described in the claims, as grasped from the embodiment, will be described below.

  (1) The propeller shaft according to claim 1, wherein the inclined portion is formed in an upward inclined shape toward the boot.

  Since the grease that has flowed into the ventilation passage is returned to the inside of the boot along the inclined portion by the centrifugal force of the propeller shaft, the grease does not flow out to the outside.

  (2) The ventilation passage is formed in an inclined shape toward the inside of the boot on the inner periphery of the fixed side at least on one end side of the boot. Propeller shaft.

  (3) The propeller shaft according to (1) or (1), wherein the ventilation passage is formed by a through hole provided in the drive shaft member or the driven shaft member.

  (4) The propeller shaft according to (3), wherein the boot cover is formed of a material harder than the boot.

  According to the present invention, when the boot tries to bend and deform due to the centrifugal force of the propeller shaft, this displacement can be suppressed only by the hard boot cover, so that excessive deformation of the boot can be prevented and the structure Therefore, it is possible to prevent an increase in the number of parts.

  (4) The propeller shaft according to (3), wherein the boot is formed of soft silicon rubber, and the boot cover is formed of hard chloroprene rubber.

  (5) The propeller shaft according to (3), wherein a reinforcing member is provided on an outer peripheral side of the boot cover.

  Even when a large centrifugal force acts on the boot cover with the rotation of the propeller shaft, the reinforcement member can restrict the deformation of the boot cover. This makes it possible to reliably prevent excessive deformation of the boot.

  (6) In the boot, the outer peripheral portion is formed substantially in a folded shape from the center portion, and the outer peripheral end of the outer peripheral portion is fixed to the drive shaft member or the driven shaft member. The propeller shaft according to any one of claims (3) to (5), wherein one end side of the boot side is extended to the central portion side through an inner peripheral portion of the boot.

  When the boot tries to bend outward by centrifugal force, the center side is restricted by the one end side of the boot cover, so that the outer peripheral part comes into contact with the fixing member on the outer peripheral side. It can be surely prevented.

  Thereby, the interference between the boot and the fixing member is prevented, and the durability of the boot can be improved.

  (7) The propeller shaft according to any one of (2) to (6), wherein the ventilation passage is configured by a groove formed on an inner peripheral surface on one end side of the boot.

  The present invention is not limited to the configuration of each of the embodiments described above. For example, as the molding material of the boot 10, it is possible to use a flexible synthetic rubber in addition to the silicon rubber, The molding material is not limited to chloroprene rubber, and molding with a harder synthetic rubber material is also possible.

  It is also possible to form a plurality of the ventilation grooves 14.

  Further, the reinforcing member can be embedded in the inside of the boot cover 16 in advance when the boot cover 16 is formed, and can be formed in a cored bar state.

  Further, the propeller shaft can be applied to other equipment such as a ship in addition to the vehicle.

It is a longitudinal cross-sectional view of the principal part which shows 1st Embodiment of the propeller shaft which concerns on this invention. It is a side view showing a section of a propeller shaft provided for this embodiment. It is a longitudinal cross-sectional view which shows the state which the boot provided for this embodiment bent outward and deform | transformed with the centrifugal force. It is a longitudinal cross-sectional view which shows the state which the boot of this embodiment bent further outward by the centrifugal force, and was deformed. It is a principal part longitudinal cross-sectional view which shows the 2nd Embodiment of this invention. It is a principal part longitudinal cross-sectional view which shows the 3rd Embodiment of this invention. It is a principal part longitudinal cross-sectional view which shows the 4th Embodiment of this invention. It is a principal part longitudinal cross-sectional view which shows the 5th Embodiment of this invention.

Explanation of symbols

1 ... propeller shaft 3 ... driven shaft (driven shaft member)
4. Constant velocity joint (joint mechanism)
10 ... Boot 12 ... Tubular wall 14 ... Ventilation groove (ventilation passage)
14a ... Bottom (inclined part)
16 ... Boot cover

Claims (3)

A joint mechanism for transmitting rotational force from the drive shaft member to the driven shaft member;
A boot having one end attached to the drive shaft member of the joint mechanism and the other end attached to the driven shaft member to cover the outer periphery of the joint mechanism and filled with lubricating grease of the joint mechanism on the inside When,
A ventilation passage that communicates the inside and outside of the boot and has an inclined portion that is inclined toward the outer periphery;
A propeller shaft characterized by comprising: A joint mechanism for transmitting rotational force from the drive shaft member to the driven shaft member;
One end of the joint mechanism is attached to the drive shaft member, the other end is attached to the driven shaft member to cover the outer periphery of the joint mechanism, and the inside is filled with lubricating grease for the joint mechanism Rubber boots,
A ventilation passage formed on at least the fixed-side inner peripheral surface of the one end of the boot and communicating with the inside and outside of the boot,
The propeller shaft according to claim 1, wherein the ventilation passage is formed so as to be able to incline toward an outer peripheral side by bending deformation due to centrifugal force of the boot. A joint mechanism for transmitting rotational force from the drive shaft member to the driven shaft member;
A boot having one end attached to the drive shaft member of the joint mechanism and the other end attached to the driven shaft member covering the outer periphery of the joint mechanism and filled with lubricating grease of the joint mechanism When,
A vent passage formed on at least one fixed side inner peripheral surface of the one end of the boot and communicating between the inside and outside of the boot;
A boot cover provided on the outer periphery of the boot forming at least the ventilation passage of the boot;
A propeller shaft, wherein the boot is formed of a material that can be deformed by centrifugal force, and the boot cover is formed of a material having rigidity higher than that of the boot.

Images