JP2006151056A - Impact-absorbing propeller shaft for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily set impact absorption characteristic when a propeller shaft receives axial impact, contraction of an inner and an outer of two division shaft progresses and a distal end surface of the outer is collision-contacted with a side of a distal end surface of a bearing inserted/attached to an intermediate part of the inner. <P>SOLUTION: In the impact-absorbing propeller shaft 10 for the automobile, when both division shafts 11, 12 are contracted each other by impact applied to one division shaft 11, the distal end surface 21B of the outer 21 is collision-contacted with the side of the distal end surface of the bearing 40 and the bearing 40 is made slidable to the inner 22. Projections 61 are provided at a plurality of positions in a circumferential direction of an outer periphery, i.e., an outer periphery of the inner 22 and continued on the intermediate part inserted/attached with the bearing 40 with the same diameter and clamping the intermediate part between a distal end fitted to the outer 21 and it. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a shock absorbing propeller shaft for an automobile.

  As a shock-absorbing propeller shaft for automobiles, a plurality of split shafts are formed by constant velocity universal joints configured by engaging outer races provided on one split shaft with bearings attached to the outer periphery of an inner shaft provided on the other split shaft. There is something that is connected. The inner shaft has a support bracket supported by a bearing inserted in the middle portion.

In Patent Document 1, as the shock absorbing structure of the shock absorbing propeller shaft for an automobile, the outer race is formed into a bottomed disk shape, and a thin wall portion is formed in a portion of the bottom wall of the inner shaft facing the axial direction. The thing is disclosed. When the propeller shaft receives an axial impact and the inner shaft and the outer race contract each other, the inner shaft breaks through the opposing thin wall portion to absorb the impact.
JP 10-250390 A

  In the shock absorbing propeller shaft for an automobile disclosed in Patent Document 1, the propeller shaft receives an axial impact, the inner shaft and the outer race are contracted, and the front end of the outer race is inserted into the middle portion of the inner shaft. There is no consideration for the impact absorption after impacting the surface.

  The problem of the present invention is that the propeller shaft is subjected to an axial impact, and the inner and outer contractions of the two split shafts progress, and the outer tip side of the bearing is inserted into the intermediate part of the inner side of the bearing. The purpose is to simply set the shock absorption characteristics when it hits the surface.

  According to the first aspect of the present invention, a plurality of split shafts are connected by constant velocity joints, and a cylindrical outer of a constant velocity joint provided on one split shaft is connected to a shaft inner of a constant velocity joint provided on the other split shaft. When the front end is fitted, the bearing inserted in the middle part of the inner is supported by the support bracket, and when the one split shaft and the other split shaft contract with each other due to the impact received by one split shaft, In the shock absorbing propeller shaft for automobiles in which the outer end surface of the outer abuts against the end surface of the bearing and is slidable with respect to the inner, it is the outer periphery of the inner, and the intermediate portion where the bearing is inserted Convex portions are provided at a plurality of circumferential positions on the outer periphery sandwiching the intermediate portion where the bearing is inserted between the tip portion and the tip portion fitted to the outer portion.

  According to a second aspect of the present invention, in the first aspect of the present invention, the bearing is sandwiched between two stopper pieces press-fitted into the inner and supported by a support bracket via a rubber-like elastic member. The front end surface comes into contact with the front end surface of the bearing through the stopper piece.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the convex portion provided on the outer periphery of the inner has a straight shape along the axial direction of the inner.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the convex portion provided on the outer periphery of the inner has a helical shape that intersects the axial direction of the inner.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, an impact absorbing plate is provided on a portion of the inner peripheral portion of the outer that is spaced apart and opposed to the inner in the axial direction. When the one split shaft and the other split shaft contract each other due to the impact received on the split shaft, the shock absorbing plate attached to the outer first comes into contact with the tip of the inner, and the shock absorbing plate is broken. Subsequently, the outer end surface of the outer abuts against the end surface of the bearing so that the bearing can slide with respect to the inner.

(Claim 1)
(a) The propeller shaft receives an impact in the axial direction, and the contraction of the inner and outer of the two split shafts advances, and the outer end surface of the outer shaft comes into contact with the end surface of the bearing that is inserted in the middle part of the inner Then, the outer slides the bearing with respect to the inner, further contracts the outer with respect to the inner, and further absorbs and reduces the impact by the sliding friction. At this time, the convex portion provided on the outer periphery of the inner on which the bearing slides increases the sliding friction load, and as a result, the impact load absorption characteristic can be easily adjusted.

(Claim 2)
(b) The front end surface of the outer is in contact with the front end surface of the bearing through the stopper piece, pierces the rubber-like elastic member between the bearing and the support bracket, and slides the bearing and the stopper piece with respect to the inner. The sliding friction load of the bearing and the stopper piece with respect to the outer periphery of the inner increases due to the presence of the convex portion.

(Claim 3)
(c) The sliding friction load of the bearing and the stopper piece with respect to the outer periphery of the inner increases due to the presence of the straight convex portion.

(Claim 4)
(d) The sliding friction load of the bearing and the stopper piece with respect to the outer periphery of the inner increases due to the presence of the helical convex portion.

(Claim 5)
(e) Since the shock absorbing plate is provided on the inner peripheral portion of the outer, as the inner and outer contract by the axial shock received by the propeller shaft, the shock is first absorbed and relaxed by breaking the shock absorbing plate. By (a) to (d), the impact is further absorbed and mitigated by the sliding of the bearing (and the stopper piece) with respect to the inner.

  FIG. 1 is an overall view showing a shock absorbing propeller shaft for an automobile of Example 1, FIG. 2 shows an impact absorbing propeller shaft for an automobile of Example 1, (A) is a sectional view, and (B) is B of (A). FIG. 3 is a cross-sectional view taken along the line -B, FIG. 3 shows a shock absorbing propeller shaft for an automobile of Example 2, (A) is a cross-sectional view, and (B) is a cross-sectional view taken along the line BB in (A).

Example 1 (FIGS. 1 and 2)
As shown in FIG. 1, an impact absorbing propeller shaft 10 for an automobile (FR vehicle or 4WD vehicle) includes two shaft members divided into a front divided shaft 11 and a rear divided shaft 12. Are connected by a constant velocity joint (slidable joint) 20. The front end of the front split shaft 11 is connected to a connecting yoke 14 connected to the output shaft of the engine-side transmission via a universal joint 13, and the rear end of the rear split shaft 12 is connected to a universal joint 15. Thus, it is coupled to a coupling yoke 16 connected to the differential gear.

  In the propeller shaft 10, a cylindrical outer 21 of the constant velocity joint 20 is connected to one end of a hollow pipe 11 </ b> A constituting one split shaft 11 by friction welding. Further, the inner shaft 22 of the constant velocity joint 20 is connected to one end of the other split shaft 12. The inner 22 is fitted to the outer 21.

  As shown in FIG. 2, the constant velocity joint 20 includes an outer race 21A for an outer 21 provided on one split shaft 11 and an inner shaft 22A for an inner 22 provided on the other split shaft 12. Three bearings 22B (tripods) are provided at three positions on the outer periphery of the tip. Each bearing 22B of the inner 22 is slidably engaged with three grooves extending in the axial direction of the inner peripheral surface of the outer race 21A to constitute the constant velocity joint 20.

  The bearing 22B of the constant velocity joint 20 protrudes radially from three positions on the outer periphery 22C of the inner ring 22C that fits into a serration formed on the outer periphery of the inner shaft 22A. The inner ring 22C having the bearing 22B is sandwiched between a retaining ring 23 engaged with an annular groove provided at the front end of the inner shaft 22A and an annular stopper 24 provided at the rear end of the inner shaft 22A, and positioned on the inner shaft 22A. Retained. Accordingly, the stopper 24 prevents the bearing 22B from moving rearward in the axial direction with respect to the inner shaft 22A with a predetermined force.

  However, the propeller shaft 10 is an inner peripheral portion 25 of the outer race 21A that constitutes the outer 21, and is provided with a shock absorbing plate 30 attached to a portion facing the inner shaft 22A of the inner 22 that is spaced apart in the axial direction. It was.

  The shock absorbing plate 30 is made of resin (or metal), and the outer diameter portion of the outer peripheral boss 31 is press-fitted into the inner diameter portion of the inner peripheral portion 25 of the outer race 21A, and is attached to the inner peripheral portion 25 of the outer race 21A.

  When the front split shaft 11 and the outer 21 (outer race 21A) and the rear split shaft 12 and the inner 22 (inner shaft 22A and the bearing 22B) contract with each other (relatively shortened) due to an impact load caused by a car collision, When the front end portion (inner shaft 22A and bearing 22B) of the inner 22 abuts against the impact absorbing plate 30 attached to the inner peripheral portion 25 of the outer race 21A, the inner 22 (inner shaft 22A and bearing 22B) is caused by an impact load. The shock absorbing plate 30 is punched from the inner peripheral portion 25 of the outer race 21A and / or the shock absorbing plate 30 is broken and penetrated.

  Further, the propeller shaft 10 rotatably supports the bearing 40 inserted in the intermediate portion of the inner shaft 22A constituting the inner 22 on the annular support member 50, and supports the annular support member 50 on the support bracket 50A. .

  The annular support member 50 is formed by joining an inner ring 51 and an outer ring 52 via a rubber-like elastic member 53. The inner ring 51 has a diameter such as a small diameter part 51A, a medium diameter part 51B, and a large diameter part 51C. The outer ring 40A of the bearing 40 is fitted inside the middle diameter part 51B, the small diameter part 51A extends to the outer periphery of a stopper piece 41 described later, and the large diameter part 51C is a stopper piece 42 described later. It extends to the outer periphery. In the inner ring 51, seal members 54 and 55 are loaded on the inner circumferences of the small diameter portion 51A and the large diameter portion 51C, respectively, and both the seal members 54 and 55 seal the bearing 40 from both sides. The seal member 54 is in sliding contact with the outer periphery of the stopper piece 41, and the seal member 55 is in sliding contact with the outer periphery of the stopper piece 42.

  In the propeller shaft 10, the bearing 40 fitted to the inner ring 51 of the annular support member 50 is loaded in the middle part of the inner shaft 22 </ b> A of the inner 22, and in this state, both sides sandwich the bearing 40 at the middle part of the inner shaft 22 </ b> A. It is assumed that the annular stopper pieces 41 and 42 are press-fitted into each other. As a result, the inner ring 40B of the bearing 40 is positioned by being sandwiched between the end faces of the stopper pieces 41 and 42.

  The stopper piece 41 includes a large-diameter flange portion 41A and a small-diameter flange portion 41B. The large-diameter flange portion 41 </ b> A of the stopper piece 41 is close to the inner periphery of the outer end of the small-diameter portion 51 </ b> A of the inner ring 51 of the annular support member 50 and allows water to enter the inside of the inner ring 51 housing the bearing 40. To prevent. Further, the water that has entered from the gap between the large-diameter flange portion 41A and the inner ring 51 is guided by the annular groove 41C between the large-diameter flange portion 41A and the small-diameter flange portion 41B and falls downward to enter the inner ring 51. To prevent the ingress of water. The stopper piece 42 also includes a large diameter flange portion 42A and a small diameter flange portion 42B. The large-diameter flange portion 42 </ b> A of the stopper piece 42 is close to the inner periphery of the outer end of the large-diameter portion 51 </ b> C of the inner ring 51 of the annular support member 50, and water enters the inside of the inner ring 51 containing the bearing 40. To prevent. Further, the water that has entered from the gap between the large-diameter flange portion 42A and the inner ring 51 is guided downward by the annular groove 42C between the large-diameter flange portion 42A and the small-diameter flange portion 42B, and falls into the inner ring 51. To prevent the ingress of water.

  When the front split shaft 11 and the outer 21 (outer race 21A) and the rear split shaft 12 and the inner 22 (inner shaft 22A and bearing 22B) contract with each other due to an impact load due to a collision of the automobile, the outer 21 (outer race 21A). The front end surface 21B of the bearing 40 comes into contact with the front end surface of the stopper piece 41 with a boot 72 (described later) sandwiched between the front end surface of the bearing 40 and the bearing 40 together with the stopper pieces 41 and 42 at the intermediate portion of the inner shaft 22A. To be slidable.

  Here, in the propeller shaft 10, as shown in FIG. 2, the outer circumference of the inner shaft 22 </ b> A of the inner 22 has the same outer diameter at the intermediate portion (bearing insertion range A) where the bearing 40 is inserted. The outer periphery (bearing sliding range B), and the outer periphery sandwiching the bearing insertion range A in which the bearing 40 is inserted between the outer end 21 (outer race 21A) and the front end (bearing 22B). The convex portions 61 are provided by rolling or cutting at a plurality of circumferential positions. In the present embodiment, the convex portion 61 forms a straight spline extending along the axial direction of the inner shaft 22A over the entire length of the bearing sliding range B, which is continuous with the insertion range A of the inner shaft 22A. The part of the same diameter shaft with respect to the bearing sliding range B was extruded by roller rolling. Therefore, the reference outer diameter other than the extruded convex portion 61 is substantially the same as the outer diameter of the bearing insertion range A.

  The constant velocity joint 20 seals the connection space (grease filling chamber) 70 between the outer 21 and the inner 22 using a boot adapter 71 made of a metal thin plate and a boot 72 made of a rubber-like elastic body, and the inner shaft 22A. Grease for improving the rolling slidability and wear resistance of the bearing 22B is enclosed in the connection space 70.

The shock absorbing operation of the propeller shaft 10 is as follows.
(1) When an impact load from the front acts on the propeller shaft 10 due to a vehicle collision, the front split shaft 11 and the outer 21 (outer race 21A) move rearward, and the rear split shaft 12 and the inner 22 (inner shaft 22A). And the bearing 22B) are inserted into the outer race 21A.

  (2) When the inner 22 (the inner shaft 22A and the bearing 22B) comes into contact with the shock absorbing plate 30 attached to the inner peripheral portion 25 of the outer race 21A as a result of the above (1), the inner load 22 ( The inner shaft 22A and the bearing 22B) punch the impact absorbing plate 30 from the inner peripheral portion 25 of the outer race 21A and / or break through the impact absorbing plate 30, and the outer 21 and the inner 22 contract.

  (3) In the process of the above (2), in the inner 22, the stopper 24 which positions the inner ring 22C of the bearing 22B is broken, and the inner ring 22C further exceeds the stopper 24 from the serration of the inner shaft 22A, and the bearing 22B. Then, of the inner shaft 22A and the bearing 22B constituting the inner 22, only the inner shaft 22A removes the shock absorbing plate 30 from the inner peripheral portion 25 of the outer race 21A and / or the shock absorbing plate 30. Break through.

  (4) When the outer 21 and the inner 22 are further contracted through the above (2), the front end surface 21B of the outer 21 (outer race 21A) is pressed into the intermediate portion of the inner 22 (inner shaft 22A) with the boot 72 interposed therebetween. The outer 21 is brought into contact with the front end surface of the stopper piece 41, and the outer 21 slides the bearing 40 together with the stopper pieces 41 and 42 with respect to the intermediate portion of the inner 22 (inner shaft 22A), thereby further contracting the outer 21 and the inner 22.

  (5) As described above, the front split shaft 11 and the rear split shaft 12 are contracted with each other without protruding, and the drive unit including the internal combustion engine in the engine room is appropriately retracted to reduce the impact. To do.

According to the present embodiment, the following operational effects can be obtained.
(a) The propeller shaft 10 receives an impact in the axial direction, and the contraction of the inner 22 and the outer 21 of the two split shafts 11 and 12 proceeds, and the tip surface 21B of the outer 21 is inserted into the intermediate portion of the inner 22. When it comes into contact with the front end surface of the bearing 40, the outer 21 slides the bearing 40 with respect to the inner 22, further contracting the outer 21 with respect to the inner 22, and further absorbing and mitigating the impact by the sliding friction. . At this time, the convex portion 61 provided on the outer periphery of the inner 22 on which the bearing 40 slides increases the sliding friction load, and as a result, the impact load absorption characteristic can be easily adjusted.

  (b) The front end surface 21B of the outer 21 abuts against the front end surface of the bearing 40 through the stopper piece 41, breaks through the rubber-like elastic member 53 between the bearing 40 and the support bracket 50A, and the bearing 40 and the stopper pieces 41, 42 are obtained. Is slid with respect to the inner 22. The sliding friction load of the bearing 40 and the stopper pieces 41 and 42 with respect to the outer periphery of the inner 22 increases due to the presence of the convex portion 61.

  (c) The sliding friction load of the bearing 40 and the stopper pieces 41, 42 with respect to the outer periphery of the inner 22 can be easily reduced by the presence of the straight convex portion 61.

  (d) Since the shock absorbing plate 30 is provided on the inner peripheral portion of the outer 21, the shock absorbing plate 30 is first broken or punched as the inner 22 and the outer 21 contract due to the axial shock received by the propeller shaft 10. Then, the impact is further absorbed and reduced by the sliding of the bearing 40 (and the stopper pieces 41 and 42) with respect to the inner 22 according to the above-described (a) to (c).

(Example 2) (FIG. 3)
3 differs from Example 1 in FIG. 2 in that a convex portion 62 is provided in place of the convex portion 61 on the outer periphery of the bearing sliding range B of the inner shaft 22A of the inner 22. The convex portion 62 is a helical convex portion that intersects the axial direction of the inner shaft 22 </ b> A, and is continuous over the entire length of the bearing sliding range B.

  According to the present embodiment, the sliding friction load of the bearing 40 and the stopper pieces 41 and 42 with respect to the outer periphery of the inner 22 adjusts the amount of twist of the helical convex portion due to the presence of the helical convex portion 62, so that the sliding friction absorbing load is adjusted. Can be further fine-tuned.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in the present invention. For example, the convex portions of the present invention are not limited to those provided in the form of a continuous long groove in the axial direction of the outer periphery of the inner, and the convex portions provided in the axial direction of the outer periphery of the inner may be discontinuous. Alternatively, circular protrusions may be distributed on the outer periphery of the outer periphery.

FIG. 1 is an overall view showing a shock absorbing propeller shaft for an automobile according to a first embodiment. 2A and 2B show an automobile impact absorbing propeller shaft according to the first embodiment, in which FIG. 2A is a cross-sectional view and FIG. 2B is a cross-sectional view taken along line BB in FIG. 3A and 3B show a shock absorbing propeller shaft for an automobile according to a second embodiment. FIG. 3A is a cross-sectional view, and FIG. 3B is a cross-sectional view taken along line BB in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Propeller shaft 11, 12 Split shaft 20 Constant velocity joint 21 Outer 21B End surface 22 Inner 30 Shock absorbing plate 40 Bearing 41, 42 Stopper piece 50A Support bracket 53 Rubber-like elastic members 61, 62 Convex part

Claims (5)

A plurality of split shafts are connected by a constant velocity joint, and the tip of the constant inner joint of the constant velocity joint provided on the other split shaft is fitted to the cylindrical outer of the constant velocity joint provided on one split shaft, Support the bearing inserted in the middle part of the inner to the support bracket,
When the one split shaft and the other split shaft contract with each other due to the impact received on one split shaft, the outer end surface of the outer abuts against the front end surface of the bearing, and the bearing slides against the inner. In an automobile shock absorbing propeller shaft that enables
A plurality of circumferential directions on the outer circumference of the inner circumference, which have the same diameter as the intermediate portion where the bearing is inserted, and sandwich the intermediate portion where the bearing is inserted between the outer end and the tip portion fitted to the outer A shock-absorbing propeller shaft for automobiles, wherein a convex portion is provided at a position. The bearing is sandwiched between two stopper pieces press-fitted into the inner, and supported by a support bracket via a rubber-like elastic member,
The shock absorbing propeller shaft for an automobile according to claim 1, wherein a front end surface of the outer abuts against a front end surface of the bearing via a stopper piece.   The shock absorbing propeller shaft for an automobile according to claim 1 or 2, wherein the convex portion provided on the outer periphery of the inner has a straight shape along the axial direction of the inner.   The shock absorbing propeller shaft for an automobile according to claim 1 or 2, wherein a convex portion provided on an outer periphery of the inner has a helical shape intersecting with an axial direction of the inner. A shock absorbing plate is provided in the inner peripheral portion of the outer and facing away from the inner in the axial direction,
When the one split shaft and the other split shaft contract each other due to an impact received on one split shaft, the shock absorbing plate attached to the outer first comes into contact with the tip of the inner, and the shock absorbing plate 5. The automobile shock absorbing device according to claim 1, wherein the outer end surface of the outer member abuts against the front end surface side of the bearing so that the bearing can slide relative to the inner. Propeller shaft.

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