JP6286942B2 - Rear axle structure of the vehicle - Google Patents

Description

  The present invention relates to a vehicle having a rigid axle-type rear suspension in which a right wheel and a left wheel are connected by a single axle pipe, particularly for fixing a spindle supporting the left wheel and the right wheel to the axle pipe. Concerning structure.

  Rigid axle type rear suspensions are widely used in vehicles such as passenger cars. For example, as disclosed in Patent Document 1, this type of rear suspension includes a pair of spindles that rotatably support a left wheel and a right wheel, and a single axle pipe that connects the spindles. I have.

  Both ends of the axle pipe along the longitudinal direction are supported by the vehicle body via shock absorbers each combining a coil spring and a shock absorber. Further, the axle pipe has an open end opened toward the spindle, and the end of the spindle is abutted so as to close the open end. The end of the spindle is integrally fixed to the axle pipe by welding to the opening end of the axle pipe over the entire circumference.

Japanese Utility Model Publication No. 62-196702

  According to the conventional rear suspension, most of the impact acting on the spindle from the road surface while the vehicle is traveling is received by the welded portion between the spindle and the axle pipe.

  However, the end of the spindle is only welded in a state where it abuts against the opening end of the axle pipe. For this reason, it is inevitable that a large stress is concentrated on the welded portion between the spindle and the axle pipe, which causes a negative effect on the durability of the rear suspension.

  SUMMARY OF THE INVENTION An object of the present invention is to obtain a vehicle rear axle structure that can suppress the concentration of stress on the coupling portion between the opening end of the axle pipe and the spindle, increase the bending rigidity of the axle pipe, and has excellent durability. is there.

  In order to achieve the above object, a vehicle rear axle structure according to one aspect of the present invention includes an axle pipe having an open end, a spindle welded to the open end of the axle pipe, and rotatably supporting a wheel. A spring seat fixed to the end of the axle pipe and receiving a suspension coil spring interposed between the vehicle body and the vehicle body.

The spindle has an extension portion that extends from the opening end of the axle pipe to a position below the spring seat. The extension portion has an outer peripheral surface that abuts on the inner peripheral surface of the axle pipe at a position where a central axis of the suspension coil spring intersects the axle pipe, and extends from the suspension coil spring through the spring seat. The load transmitted to the axle pipe is received.

  According to a preferred embodiment of the present invention, a protrusion projecting inside the axle pipe is formed on the inner peripheral surface of the axle pipe positioned on the opening end side of the tip of the extension portion of the spindle.

  According to a preferred embodiment of the present invention, the protrusion is formed of a welded portion that joins the outer edge of the spring seat to the outer peripheral surface of the axle pipe.

  According to a preferred embodiment of the present invention, the extension portion of the spindle has a relief portion separated from the inner peripheral surface of the axle pipe at a position corresponding to the protrusion.

  According to the present invention, the load applied to the welded portion between the spindle and the opening end of the axle pipe can be reduced, and the load applied to the axle pipe from the suspension coil spring can be received by the extension portion of the spindle. Therefore, the bending rigidity of the axle pipe can be increased, and the durability around the spindle is improved.

1 is a perspective view of a vehicle according to a first embodiment. 1 is a cross-sectional view schematically showing a rigid axle type rear suspension in which a pair of spindles that support a right wheel and a left wheel are connected by a single axle pipe in the first embodiment. 1 is a perspective view showing a left end portion of a rigid axle type rear suspension according to a first embodiment. FIG. FIG. 4 is a perspective view of the rigid axle type rear suspension shown in FIG. 3 as viewed from the direction of arrow A in FIG. 3. FIG. 4 is a perspective view of the rigid axle type rear suspension shown in FIG. 3 as viewed from the direction of arrow B in FIG. 3. It is sectional drawing of the left end part of the rigid axle type rear suspension which concerns on 1st Embodiment. It is a top view of the spindle used in a 1st embodiment. It is sectional drawing of the left end part of the rigid axle type rear suspension which concerns on 2nd Embodiment. It is sectional drawing of the left end part of the rigid axle type rear suspension which concerns on 3rd Embodiment.

[First Embodiment]
Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 6.

  FIG. 1 shows a passenger car 1 which is an example of a vehicle. A left wheel 3a and a right wheel 3b are disposed at the rear of the vehicle body 2 of the passenger car 1. The left wheel 3 a and the right wheel 3 b are supported by the vehicle body 2 via a rigid axle type rear suspension 4.

  As shown in FIG. 2, the rear suspension 4 includes left and right trailing arms 5 a and 5 b, left and right spindles 6 a and 6 b, and an axle pipe 7. The trailing arms 5 a and 5 b extend in the front-rear direction of the vehicle body 2 and are arranged at intervals in the width direction of the vehicle body 2.

  Each of the trailing arms 5a and 5b has a front end portion 8 and a rear end portion 9 as representatively shown on the left side trailing arm 5a in FIGS. The front end portions 8 of the trailing arms 5a and 5b are rotatably supported by the vehicle body 2. Lower brackets 11 are fixed to the rear ends 9 of the trailing arms 5a and 5b, respectively.

  The axle pipe 7 is welded to the lower bracket 11 so as to straddle between the rear ends 9 of the trailing arms 5a and 5b. The axle pipe 7 of the present embodiment is formed of a round pipe and has circular opening ends 7a and 7b at both ends along the axial direction.

  Spring seats 12a and 12b are attached to both ends of the axle pipe 7, respectively. The spring seats 12 a and 12 b are elements that receive the suspension coil pile 13 that is installed between the spring seats 12 a and 12 b, and are adjacent to the opening ends 7 a and 7 b of the axle pipe 7.

  The spring seats 12 a and 12 b each have a joint portion 14 that spreads in a flare shape along the outer peripheral surface of the axle pipe 7. The outer edge portion 14 a of the joint portion 14 is welded to the outer peripheral surface of the axle pipe 7 at a plurality of locations. For this reason, in this embodiment, the some welding part 15 is formed ranging between the outer edge part 14a of the junction part 14, and the axle pipe 7. As shown in FIG. The welded portions 15 are arranged at intervals in the circumferential direction of the joint portion 14.

  Further, as the spring seats 12a and 12b are welded to the axle pipe 7, a protrusion 16 as shown in FIG. 6 is formed at a location corresponding to the welded portion 15 on the inner peripheral surface of the axle pipe 7. Yes. The protrusion 16 protrudes toward the inside of the axle pipe 7.

  As shown in FIGS. 3 to 5, a shock absorber bracket 17 is provided behind the spring seats 12a and 12b. The shock absorber bracket 17 is welded to the axle pipe 7 and the lower bracket 11. The shock absorber bracket 17 is connected to a lower end portion of a shock absorber (not shown) installed between the vehicle body 2 and the shock absorber bracket 17.

  The left and right spindles 6a and 6b are elements that rotatably support the left wheel 3a and the right wheel 3b, and have a common configuration. Therefore, in the present embodiment, the left spindle 6a will be described as a representative, and the right spindle 6b will be denoted by the same reference numeral, and the description thereof will be omitted.

  As shown in FIGS. 3 to 6, the spindle 6 a is an integral structure having a spindle body 20, a spindle shaft portion 21, and an extension portion 22. The spindle body 20 is formed in a solid cylindrical shape, and has a flange portion 23 at one end thereof. One end of the spindle body 20 including the flange portion 23 has a size capable of closing the opening end 7 a of the axle pipe 7.

  One end of the spindle main body 20 is welded over the entire circumference of the opening end 7 a in a state of abutting against the opening end 7 a of the axle pipe 7. As a result, a welded portion 24 that is continuous in the circumferential direction of the axle pipe 7 is formed at the boundary between one end of the spindle body 20 and the axle pipe 7.

  Further, a brake bracket 25 is welded to the outer peripheral surface of the spindle body 20. The brake bracket 25 supports a back plate of a drum brake provided on the left wheel 3a.

  The spindle shaft portion 21 protrudes coaxially from the other end of the spindle body 20 toward the opposite side of the flange portion 23. The spindle shaft portion 21 is an element that rotatably supports a hub in which the drum brake is built, and the wheel of the left wheel 3a is fixed to the hub.

  As shown in FIGS. 6 and 7, the extension portion 22 of the spindle 6 a protrudes coaxially from one end of the spindle body 20 toward the opposite side of the spindle shaft portion 21. In other words, the extension 22 is extended from the opening end 7 a of the axle pipe 7 so as to enter the inside of the axle pipe 7.

  The extension 22 of this embodiment is a solid columnar element. The extension portion 22 has a small diameter portion 27 and a large diameter portion 28. The small diameter portion 27 protrudes from one end of the spindle body 20. The small diameter portion 27 is an example of an escape portion and has an outer diameter smaller than the inner diameter of the axle pipe 7. The outer peripheral surface of the small diameter portion 27 is separated from the inner peripheral surface of the axle pipe 7. Therefore, a gap 29 continuous in the circumferential direction is formed between the outer peripheral surface of the small diameter portion 27 and the inner peripheral surface of the axle pipe 7.

  The large diameter portion 28 is located at the tip of the extension portion 22. The outer peripheral surface of the large-diameter portion 28 is configured to contact the inner peripheral surface of the axle pipe 7 immediately below the center portion of the spring seat 12a. In the present embodiment, the outer peripheral surface of the large diameter portion 28 is welded to the inner peripheral surface of the axle pipe 7 over the entire periphery. Therefore, a welded portion 31 that is continuous in the circumferential direction of the axle pipe 7 is formed between the outer peripheral surface of the large-diameter portion 28 and the inner peripheral surface of the axle pipe 7, and the spindle shaft portion 21 is firmly fixed to the axle pipe 7. Has been. Furthermore, according to the present embodiment, the welded portion 31 between the outer peripheral surface of the large diameter portion 28 and the inner peripheral surface of the axle pipe 7 is provided at a position where the central axis O1 of the suspension coil pull ring 13 intersects the axle pipe 7. It has been. In other words, the extension 22 of the spindle 6 a is abutted against the inner peripheral surface of the axle pipe 7 at a position where the central axis O 1 of the suspension coil ring 13 intersects the axle pipe 7 and is welded to the axle pipe 7. ing.

  In addition, in the present embodiment, one of the plurality of welded portions 15 between the spring seat 12 a and the axle pipe 7 is provided at a position corresponding to the small diameter portion 27 of the extension portion 22. For this reason, the protrusion 16 corresponding to the one welded portion 15 is positioned between the opening end 7 a and the large diameter portion 28 of the extension portion 22 in the axle pipe 7, and in the gap 29 inside the axle pipe 7. I'm here.

  As shown in FIGS. 3 to 5, a pedestal 33 is welded onto the outer peripheral portion of the joint portion 14 of the spring seat 12 a. The brake hose bracket 34 and the protector 35 are welded to the upper end portion of the pedestal 33. The brake hose bracket 34 is an element that holds a brake hose 36 spanned between the wheel cylinder of the drum brake and the vehicle body. The brake hose 36 is piped between the lower end of the suspension coil spring 13 and the drum brake back plate.

  The protector 35 is interposed between the lower end portion of the suspension coil spring 13 and the brake hose 36. The protector 35 is configured to prevent the broken suspension coil spring 13 from interfering with the brake hose 36 even when the suspension coil spring 13 is broken, for example.

  According to the first embodiment, the spindle 6a for supporting the left wheel 3a and the spindle 6b for supporting the right wheel 3b are respectively configured such that one end of the spindle body 20 is continuously connected to the opening ends 7a and 7b of the axle pipe 7 in the circumferential direction. The large-diameter portion 28 of the extension 22 that is welded and inserted inside the axle pipe 7 is continuously welded in the circumferential direction of the axle pipe 7 in contact with the inner peripheral surface of the axle pipe 7. .

  According to such a configuration, an impact transmitted from the road surface to the spindles 6 a and 6 b during traveling of the vehicle 1 is caused by the welded portion 24 between the spindle body 20 and the axle pipe 7, the extension portion 22, and the axle pipe 7. It is received by both the welding part 31 between. That is, the impact from the road surface can be transmitted not only to the welded portion 24 but also to the axle pipe 7 side via the extension 22. For this reason, the load burden in the welding part 24 is reduced, and it can avoid that stress concentrates on the welding part 24 located in the opening ends 7a and 7b of the axle pipe 7. FIG. Therefore, the welded parts 24 and 31 are hardly damaged. In addition, the spindles 6 a and 6 b can be firmly fixed to the axle pipe 7 by welding the large diameter portion 28 of the extension 22 and the axle pipe 7 to each other at the welded portion 31.

  Further, the large-diameter portion 28 of the extension portion 22 is located immediately below the central portion of the spring seats 12a and 12b, and at the position where the central axis O1 of the suspension coil spring 13 intersects the axle pipe 7 Abutted (welded). Therefore, the load applied to the axle pipe 7 from the suspension coil spring 13 via the spring seats 12a and 12b can be reliably received by the extension 22 of the spindles 6a and 6b.

  Therefore, the bending rigidity of the axle pipe 7 is improved, and the durability of the rear suspension 4 can be enhanced together with the ability to firmly fix the spindles 6a and 6b to the axle pipe 7.

  Further, according to the present embodiment, the protrusion 16 formed on the axle pipe 7 faces the gap 29 between the small diameter portion 27 of the extension 22 and the axle pipe 7. For this reason, even if the welded portions 24 and 31 are broken by an excessive impact, the large-diameter portion 28 of the extension 22 is caught by the protrusion 16. Therefore, the extension portion 22 can be prevented from coming out of the opening ends 7 a and 7 b of the axle pipe 7, and the spindles 6 a and 6 b can be held on the axle pipe 7.

[Second Embodiment]
FIG. 8 discloses a second embodiment. The second embodiment is different from the first embodiment in the configuration of the extension 22 of the spindle 6a. Other configurations of the rear suspension 4 are the same as those in the first embodiment. Therefore, in the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 8, the extension 22 is formed in a hollow shape having a center hole 41 on its axis. The center hole 41 extends over the entire length of the extension portion 22 and is opened at the end face of the large diameter portion 28.

  According to such a configuration, the extension portion 22 can be reduced in weight by the presence of the hollow hole 41. For this reason, although the extension part 22 is provided in the spindle 6a, the weight increase of the spindle 6a can be minimized.

  The center hole 41 is not specified to extend over the entire length of the extension 22, and for example, the tip of the center hole 41 may be extended to a position corresponding to the spindle body 20.

[Third Embodiment]
FIG. 9 discloses a third embodiment. The third embodiment is different from the first embodiment in the configuration of the extension 22 of the spindle 6a. Other configurations of the rear suspension 4 are the same as those in the first embodiment. Therefore, in the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 9, the extension 22 is formed in a solid columnar shape that fits tightly inside the axle pipe 7. A recess 51 is formed at a position corresponding to the protrusion 16 formed on the axle pipe 7 on the outer peripheral surface of the extension 22. The recess 51 is an example of a relief portion, and the protrusion 16 enters the inside of the recess 51.

  According to such a configuration, even if the welded portions 24 and 31 between the spindle 6 a and the axle pipe 7 are broken, the protrusion 16 is caught in the recess 51 of the extension portion 22. Therefore, the extension portion 22 can be prevented from coming out of the opening end 7 a of the axle pipe 7, and the spindle 6 a can be held on the axle pipe 7.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. For example, the extension part 22 of the spindles 6a and 6b is fixed to the axle pipe 7 by welding at a position where the central axis O1 of the suspension coil spring 13 intersects the axle pipe 7, but it is not necessarily fixed. The large diameter portion 28 may be configured to be in contact with the inner peripheral surface of the axle pipe 7. In addition, even if the large diameter portion 28 is in a position where the large diameter portion 28 is in contact with the axle pipe 7, the effect of the present invention can be sufficiently exerted as long as the spring seats 12 a and 12 b are within the region overlapping the axle pipe 7.

  Further, the extension part 22 of the spindles 6a and 6b may be fixed to the axle pipe 7 by means other than welding such as adhesion, fitting or caulking.

  2 ... Body, 3a ... Left wheel, 3b ... Right wheel, 6a, 6b ... Spindle, 7 ... Axle pipe, 7a, 7b ... Open end, 12a, 12b ... Spring seat, 13 ... Coil spring for suspension, 22 ... Extension .

Claims (4)

An axle pipe having an open end;
A spindle that is welded to the open end of the axle pipe and rotatably supports a wheel;
A rear axle structure of a vehicle comprising: a spring seat that is provided at an end of the axle pipe and receives a suspension coil spring provided between the axle pipe and the vehicle body;
The spindle has an extension portion configured to receive a load transmitted from the suspension coil spring to the axle pipe through the spring seat by extending from the opening end of the axle pipe to the lower portion of the spring seat. And
The extension portion of the spindle is configured such that an outer peripheral surface thereof abuts an inner peripheral surface of the axle pipe at a position where a central axis of the suspension coil spring intersects the axle pipe. Rear axle structure of the vehicle. The inner peripheral surface of the axle pipe from the front end of the extended portion of the spindle located at the open end, according to claim 1, characterized in that the formation of the projections projecting inwardly of the axle pipe Vehicle rear axle structure. The vehicle rear axle structure according to claim 2 , wherein the protrusion is formed of a welded portion that joins an outer edge portion of the spring seat to an outer peripheral surface of the axle pipe. The extension, the rear axle construction for a vehicle according to claim 2 or claim 3 characterized in that it has a relief portion spaced from the inner peripheral surface of the axle pipe at a position corresponding to the projection of the spindle.

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