JP2009274577A - Front fork - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid a swing movement based on a bending load of a wheel-side tube due to a fitting gap at an inner circumference of an axle bracket and an outer circumference of the wheel-side tube while preventing a slack of a screwed part of the axle bracket and the wheel-side tube. <P>SOLUTION: In this front fork 10, a tip face of a wheel-side tube 12 is collided with a bottom face at an inner circumference of an axle bracket 18, so as to fasten the wheel-side tube 12 and the axle bracket 18. Gap elimination means 70 for eliminating a fitting gap formed by the inner circumference of the axle bracket 18 and the outer circumference on a tip side of the wheel-side tube 12 is provided near an opening at the inner circumference of the axle bracket 18. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a front fork suitable for use in a motorcycle.

As described in Patent Document 1, as a front fork, the vehicle body side tube and the wheel side tube are slidably fitted, and the front end side outer peripheral portion of the wheel side tube is fitted to the inner peripheral portion of the axle bracket. There is one in which a male screw portion formed on the outer peripheral portion on the distal end side of the tube is screwed into a female screw portion formed on the inner peripheral portion of the axle bracket. In Patent Document 1, the front end surface of the wheel side tube is abutted against the bottom surface of the inner peripheral portion of the axle bracket to fasten the wheel side tube and the axle bracket (prior art 1), and the opening end of the axle bracket is provided. Each of them (prior art 2) that abuts against a stopper provided on the outer periphery of the wheel side tube is described.
Patent No. 3417698

  In Prior Art 1 described in Patent Document 1, the front end surface of the wheel side tube is abutted against the bottom surface of the inner peripheral portion of the axle bracket, and the wheel side tube and the axle bracket are fastened. It is firmly fastened to prevent loosening of the threaded portion of the axle bracket and the wheel side tube.

  Prior art 2 described in Patent Document 1 prevents swinging motion based on the bending load of the wheel-side tube caused by the fitting gap between the inner peripheral portion of the axle bracket and the outer peripheral portion of the wheel-side tube in the prior art 1 described above. As a result, an attempt is made to avoid the occurrence of creep failure near the threaded portion of the axle bracket and the wheel side tube. For this reason, in the prior art 2, a gap is provided between the front end surface of the wheel side tube and the bottom surface of the axle bracket, and the opening end portion of the axle bracket is opposed to a stopper portion provided on the outer peripheral portion of the wheel side tube. By combining, the bending load acting on the wheel side tube is transmitted to the axle bracket through the stopper part of the wheel side tube, and the swinging motion of the wheel side tube is prevented.

  However, in the related art 1 described in Patent Document 1, it is not possible to prevent the swinging motion based on the bending load of the wheel side tube resulting from the fitting gap between the inner peripheral portion of the axle bracket and the outer peripheral portion of the wheel side tube. . On the other hand, in the related art 2 described in Patent Document 1, it is impossible to prevent the screwed portion between the axle bracket and the wheel side tube from being loosened.

  An object of the present invention is to prevent the bending load of the wheel side tube caused by the fitting gap between the inner peripheral portion of the axle bracket and the outer peripheral portion of the wheel side tube while preventing the screwed portion of the axle bracket and the wheel side tube from loosening. It is to prevent the rocking motion based on.

  According to the first aspect of the present invention, the vehicle body side tube and the wheel side tube are slidably fitted, the front end side outer peripheral portion of the wheel side tube is fitted to the inner peripheral portion of the axle bracket, and the front end side outer periphery of the wheel side tube is fitted. In the front fork formed by screwing the male screw part formed on the inner part with the female screw part formed on the inner peripheral part of the axle bracket, the front end face of the wheel side tube abuts on the bottom surface of the inner peripheral part of the axle bracket. The side tube and the axle bracket are fastened, and clearance elimination means for eliminating the fitting gap formed between the inner peripheral portion of the axle bracket and the outer peripheral portion on the front end side of the wheel side tube is provided in the vicinity of the opening of the inner peripheral portion of the axle bracket. Is.

  According to a second aspect of the present invention, in the first aspect of the present invention, the gap eliminating means is fitted between the inner peripheral portion of the axle bracket and the outer peripheral portion on the front end side of the wheel side tube near the opening of the inner peripheral portion of the axle bracket. It consists of wedge-shaped parts press-fitted into the gap.

  According to a third aspect of the present invention, in the second aspect of the invention, the wedge-shaped component further includes a tapered outer peripheral surface having a diameter reduced toward the front end on the front end side of the annular body. It is inserted into the outer peripheral portion on the tip end side of the wheel side tube so that the tapered outer peripheral surface of the annular body can be press-fitted into the inner peripheral portion of the axle bracket.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, a male screw portion is further formed on the annular outer peripheral surface following the tapered outer peripheral surface of the annular body, and the male screw portion is formed on the inner peripheral portion of the axle bracket. It is made possible to tighten.

  According to a fifth aspect of the present invention, in the first aspect of the present invention, the clearance eliminating means further includes a slot extending over a certain range along the axial direction from the opening end of the axle bracket around the opening of the inner peripheral portion of the axle bracket. Further, tightening portions that are opposed to each other on both sides in the circumferential direction sandwiching the slit of the axle bracket are provided, and the corresponding tightening portions can be tightened with bolts.

(Claim 1)
(a) The front end surface of the wheel side tube is abutted against the bottom surface of the inner peripheral portion of the axle bracket, and the wheel side tube and the axle bracket are fastened to firmly fasten the axle bracket and the wheel side tube. It is possible to prevent loosening of the threaded portion of the wheel side tube.

  (b) In the vicinity of the opening of the inner peripheral portion of the axle bracket, there is provided a clearance eliminating means for eliminating the fitting gap formed by the inner peripheral portion of the axle bracket and the outer peripheral portion on the tip end side of the wheel side tube. As a result, the bending load acting on the wheel side tube is applied to the axle bracket via the clearance eliminating means while maintaining the abutting between the tip surface of the wheel side tube and the bottom surface of the inner peripheral portion of the axle bracket. Thus, the swinging movement of the wheel side tube is prevented, and as a result, the occurrence of creep destruction near the threaded portion of the axle bracket and the wheel side tube can be avoided.

(Claim 2)
(c) The clearance elimination means is composed of a wedge-shaped part that is press-fitted into the fitting gap between the inner peripheral portion of the axle bracket and the outer peripheral portion on the front end side of the wheel side tube near the opening of the inner peripheral portion of the axle bracket. . Thereby, it can press-fit by driving a wedge-shaped part etc., and can eliminate reliably the fitting gap which the inner peripheral part of an axle bracket and the front end side outer peripheral part of a wheel side tube make.

(Claim 3)
(d) The tapered outer peripheral surface of the annular body constituting the wedge-shaped part is press-fitted into the inner peripheral portion of the axle bracket, and the above (c) can be easily realized.

(Claim 4)
(e) By tightening the male thread part of the annular body constituting the wedge-shaped part into the female thread part of the axle bracket, the tapered outer peripheral surface of the annular body is press-fitted into the inner peripheral part of the axle bracket, and the above (c) is simplified. Can be realized.

(Claim 5)
(f) The clearance eliminating means is provided with a slit extending from the opening end of the axle bracket to a certain range along the axial direction around the opening of the inner peripheral portion of the axle bracket, and on both sides in the circumferential direction sandwiching the slit of the axle bracket. Opposing tightening portions were provided, and the opposing tightening portions could be tightened with bolts. Thereby, the slot of the axle bracket is tightened to reduce the diameter of the opening of the axle bracket, and the fitting gap formed by the inner peripheral portion of the axle bracket and the outer peripheral portion on the front end side of the wheel side tube can be reliably eliminated.

  1 is an overall sectional view showing a front fork, FIG. 2 is a lower sectional view of FIG. 1, FIG. 3 is an intermediate sectional view of FIG. 1, FIG. 4 is an upper sectional view of FIG. FIG. 6 is a cross-sectional view showing the clearance elimination means, FIG. 7 is a cross-sectional view showing the attachment structure of the wheel side tube of Example 2, and FIG. 8 shows the clearance elimination means. ) Is a plan view, FIG. 9B is a cross-sectional view, FIG. 9 is a cross-sectional view showing a wheel side tube mounting structure of Example 3, and FIG.

Example 1 (FIGS. 1 to 6)
As shown in FIGS. 1 to 4, the front fork 10 is configured by fitting a vehicle body side tube 11 and a wheel side tube 12 slidably in a liquid-tight manner. A bush 13 is provided on the outer periphery of the lower end of the vehicle body side tube 11, and a bush 14 is provided on the inner periphery of the upper end side of the wheel side tube 12. An oil hole 11 </ b> A is provided on the lower end side of the vehicle body side tube 11 to communicate an oil reservoir chamber 28, which will be described later, between the vehicle body side tube 11 and the wheel side tube 12 in an annular gap sandwiched between the bushes 13 and 14.

  The vehicle body side tube 11 is provided with a cap 16 detachably and liquid-tightly at the opening 15 at the upper end, and the vehicle body side tube 11 is provided with a vehicle body side mounting portion. As will be described later in detail, the wheel-side tube 12 is integrally provided with an axle bracket 18, and the axle bracket 18 is provided with an axle-side mounting portion 18 </ b> A.

  The front fork 10 accommodates a damper cylinder 21 and a piston rod 24 that constitute a damper 20 inside the vehicle body side tube 11 and the wheel side tube 12. That is, the front fork 10 has a damper cylinder 21 fixed inside the axle bracket 18 standing inside the wheel side tube 12. A stopper ring 21A engaged with the inner periphery of the lower end of the damper cylinder 21 by a bottom piece 51 to be described later, which is screwed to the bottom bolt 22 inserted into the damper cylinder 21 from the outside of the axle bracket 18 via the sealing material 22A. And the damper cylinder 21 is fixed to the bottom of the axle bracket 18 under the intervention of a flange 37A of an oil lock piece 37 described later.

  The front fork 10 has a spring load adjusting sleeve 23 screwed in a liquid-tight manner at the center of the cap 16, and a hollow piston rod 24 and a lock nut 23 </ b> A at the lower end of the spring load adjusting sleeve 23 inserted into the vehicle body side tube 11. And the piston rod 24 is fixedly supported to the vehicle body side tube 11. The piston rod 24 is slidably passed through a rod guide 25 provided at the upper end portion of the damper cylinder 21 and is inserted into an oil chamber 27 inside the damper cylinder 21. The piston rod 24 is attached to a piston bolt 24A provided at the insertion tip portion thereof. 26. The piston 26 is fixed by a nut 24B screwed to the piston bolt 24A. The piston 26 slides up and down on the inner surface of the damper cylinder 21. The oil chamber 27 is partitioned by the piston 26 into a piston rod side oil chamber 27A on the side where the piston rod 24 is inserted and a piston side oil chamber 27B on the side where the piston rod 24 is not inserted.

  The bottomed cylindrical rod guide 25 is provided with an inner collar 25C fitted with an O-ring 25B in an interior partitioned with an upper washer 25A that is caulked and fixed to the upper end portion of the damper cylinder 21, and is press-fitted into the inner collar 25C. The piston rod 24 is slidably supported by the bush 25D. The O-ring 25 </ b> B absorbs the axial misalignment between the damper cylinder 21 and the piston rod 24.

  In the front fork 10, between the vehicle body side tube 11 and the wheel side tube 12, the outer peripheral space of the damper cylinder 21 is an oil reservoir chamber 28, and the upper portion of the oil reservoir chamber 28 is a gas chamber (air chamber) 29.

  The front fork 10 includes a spring collar 31 formed by a combination of a plurality of members that are supported by the above-described spring load adjusting sleeve 23 provided on the cap 16 and moved up and down, and an upper spring seat 32 that is backed up by the spring collar 31; A suspension spring 34 is interposed between the lower spring seat 33 fixed to the outer periphery of the upper end portion of the damper cylinder 21.

  The front fork 10 buffers the impact force received from the road surface when the vehicle travels by the spring reaction force of the suspension spring 34 and the spring reaction force of the air spring of the air chamber 29.

  The damper 20 includes a piston valve device (extension-side damping force generation device) 40 and a bottom valve device (compression-side damping force generation device) 50. The damper 20 causes expansion and contraction vibration of the vehicle body side tube 11 and the wheel side tube 12 due to absorption of impact force by the suspension spring 34 and the gas spring of the air chamber 29 by the damping force generated by the piston valve device 40 and the bottom valve device 50. Suppress.

(Piston valve device 40)
The piston valve device 40 includes a pressure side channel 41 (not shown) and an extension side channel 42 that allow the piston rod side oil chamber 27A and the piston side oil chamber 27B to communicate with the piston 26 that is in sliding contact with the inner surface of the damper cylinder 21. The compression side channel 41 can be opened and closed by the compression side damping valve 43, and the extension side channel 42 can be opened and closed by the extension side damping valve 44. The compression-side damping valve 43 is backed up and supported by a valve stopper 43A that is locked by the piston rod 24. The expansion-side damping valve 44 is backed up and supported by a valve stopper 44A fixed by a nut 24B.

  Further, the piston valve device 40 has a bypass channel 46 in the piston rod 24 (piston bolt 24A) that bypasses the piston 26 and allows the piston rod side oil chamber 27A and the piston side oil chamber 27B to communicate with each other. The bypass channel 46 can be opened and closed by the needle 47A. At this time, the damping force adjusting rod 47 is screwed into the center of the spring load adjusting sleeve 23 provided on the cap 16, the damping force adjusting rod 47 is inserted into the hollow portion of the piston rod 24, and the needle 47A described above is inserted into the insertion end. Prepare.

  Therefore, when the front fork 10 is compressed, when the moving speed of the piston rod 24 is low, the oil in the piston-side oil chamber 27B is guided to the rod-side oil chamber 27A through the bypass oil passage 46 with the needle 47A. An extension side damping force is generated by the restriction resistance of the needle 47A. This damping force is adjusted by adjusting the position of the needle 47A by the damping force adjusting rod 47. When the moving speed of the piston rod 24 is medium to high, the oil in the piston-side oil chamber 27B flows into the rod-side oil chamber 27A through the pressure-side damping valve 43 of the pressure-side channel 41, and the deflection of the pressure-side damping valve 43 during this time A compression side damping force is generated by resistance.

  Further, when the front fork 10 is extended, when the moving speed of the piston rod 24 is low, the oil in the rod-side oil chamber 27A is guided to the piston-side oil chamber 27B through the bypass flow path 46 with the needle 47A. A compression side damping force is generated by the throttle resistance of the needle 47A. This damping force is adjusted by adjusting the position of the needle 47A by the damping force adjusting rod 47. Further, when the moving speed of the piston rod 24 is medium to high, the oil in the rod side oil chamber 27A flows into the piston side oil chamber 27B through the extension side damping valve 44 of the extension side flow path 42, and the extension side damping valve in the meantime. The extension side damping force due to the deflection resistance of 44 is generated.

(Bottom valve device 50)
In the bottom valve device 50, a pressure side valve 56A, a valve housing 53, and a valve stopper 54 are held by bolts 52 on a bottom piece 51 that fixes the damper cylinder 21 as described above. The valve stopper 54 holds an extension side valve (check valve) 57A and a spring 57B between the valve housing 53 and the valve stopper 53. The valve housing 53 is in liquid-tight contact with an intermediate portion of the damper cylinder 21, and forms a bottom valve chamber 55 below the piston-side oil chamber 27B. The valve housing 53 is provided with a pressure side valve 56A to allow communication between the piston side oil chamber 27B and the bottom valve chamber 55, and an expansion side valve 57A is provided with the piston side oil chamber 27B and the bottom valve chamber 55. And an extension side flow channel 57 (not shown). The bottom valve chamber 55 can communicate with an oil reservoir chamber 28 provided outside the damper cylinder 21 by an oil passage 58 provided on the wall surface of the damper cylinder 21.

  Further, the axle bracket 18, the bottom bolt 22, the bottom piece 51, and the bolt 52 can communicate with the piston-side oil chamber 27 </ b> B and the oil reservoir chamber 28 by bypassing the pressure-side channel 56 and the extension-side channel 57. A bypass channel 59 is provided. Further, a damping force adjusting rod 62 is inserted in a liquid-tight manner through an O-ring 63 and screwed into a cap 61 that is inserted in a liquid-tight manner by holding an O-ring 61A on the axle bracket 18 and is attenuated. The flow path area of the bypass flow path 59 of the wheel side tube 12 can be adjusted by the tip needle 62A of the force adjusting rod 62.

  Accordingly, when the front fork 10 is compressed, the oil corresponding to the volume of the piston rod 24 that has entered the damper cylinder 21 passes from the piston-side oil chamber 27B through the bypass channel 59 to the oil reservoir chamber 28 or the pressure-side channel 56. The oil is discharged to the oil reservoir chamber 28 through the bottom valve chamber 55 and the oil passage 58 on the wall surface of the damper cylinder 21. At this time, when the relative speed between the damper cylinder 21 and the piston rod 24 is low, a compression-side damping force is obtained by the throttling resistance of the needle 62A provided in the bypass passage 59. This damping force is adjusted by adjusting the position of the needle 62 </ b> A by the damping force adjusting rod 62. Further, when the relative speed between the damper cylinder 21 and the piston rod 24 is medium to high, the oil passing from the piston-side oil chamber 27B through the pressure-side flow path 56 is deflected and deformed by the pressure-side valve 56A and guided to the bottom valve chamber 55, A damping force is generated.

  When the front fork 10 is extended, the oil corresponding to the retraction volume of the piston rod 24 that retreats from the damper cylinder 21 is recirculated from the oil reservoir chamber 28 to the piston-side oil chamber 27B through the bottom valve chamber 55 and the expansion-side flow passage 57. The

  When the front fork 10 is compressed most, the check valve 36A of the oil lock collar 36 provided at the lower end of the vehicle body side tube 11 is fitted to the outer periphery of the oil lock piece 37 erected on the bottom of the wheel side tube 12. Then, an oil lock oil chamber is defined between the wheel side tube 12 and the oil lock piece 37 to restrict the maximum compression stroke.

  Further, when the front fork 10 is fully extended, the rebound spring 39 backed up and supported by a spring receiver 38 locked to the outer peripheral portion of the upper end of the damper cylinder 21 is compressed by the upper end washer of the oil lock collar 36 to restrict the maximum extension stroke. .

  However, in the front fork 10, when the vehicle body side tube 11 and the wheel side tube 12 are slidably fitted, as shown in FIG. The male threaded portion A that is fitted to the peripheral portion and formed on the outer peripheral portion on the front end side of the wheel side tube 12 is screwed into the female threaded portion B formed on the inner peripheral portion of the axle bracket 18, and the inner peripheral annular groove of the axle bracket 18 is The outer peripheral portion on the tip end side of the wheel-side tube 12 is liquid-tightly attached to the O-ring 19 loaded on the wheel.

  At this time, the front end surface of the wheel side tube 12 is brought into contact with the bottom surface of the inner peripheral portion of the axle bracket 18, and the male screw portion A of the wheel side tube 12 and the female screw portion B of the axle bracket 18 are fastened with a constant screwing torque. To do.

  Further, in the vicinity of the opening of the inner peripheral portion of the axle bracket 18, there is provided a clearance eliminating means 70 that eliminates the fitting gap formed by the inner peripheral portion of the axle bracket 18 and the outer peripheral portion on the front end side of the wheel side tube 12. The clearance elimination means 70 of the present embodiment is a wedge-shaped part that is press-fitted into the fitting gap between the inner peripheral portion of the axle bracket 18 and the outer peripheral portion on the front end side of the wheel side tube 12 near the opening of the inner peripheral portion of the axle bracket 18. 71.

  As shown in FIG. 6, the wedge-shaped component 71 includes an annular body 72, and includes a tapered outer peripheral surface 72 </ b> A that decreases in diameter toward the distal end on the distal end side of the annular body 72. In this embodiment, the straight outer peripheral surface 72B on the proximal end side of the annular body 72 is slightly larger in diameter than the straight outer peripheral surface 72C on the distal end side, and the tapered outer peripheral surface is more distal than the straight outer peripheral surface 72C on the distal end side. A surface 72A is provided. Further, the straight inner peripheral surface 72D on the proximal end side of the annular body 72 is slightly larger in diameter than the straight inner peripheral surface 72E on the distal end side, and the straight inner peripheral surface 72E on the distal end side is made the distal end of the wheel side tube 12. Insert on the side outer periphery. The annular body 72 has a wedge portion 72F at the intersection of the tapered outer peripheral surface 72A and the straight inner peripheral surface 72E.

  The axle bracket 18 has a straight inner peripheral surface 18A on the opening side larger than the straight inner peripheral surface 18B on the back side to which the outer peripheral portion on the distal end side of the wheel side tube 12 is fitted. The connection between the straight inner peripheral surface 18A and the straight inner peripheral surface 18B is a tapered inner peripheral surface 18C.

  The annular body 72 of the wedge-shaped part 71 is driven from the outside into the annular space of the outer periphery of the wheel side tube 12 and the inner periphery of the axle bracket 18, and the straight inner peripheral surface 72 </ b> E of the annular body 72 is the outer peripheral side on the front end side of the wheel side tube 12. The tapered outer peripheral surface 72A of the annular body 72 is press-fitted into the tapered inner peripheral surface 18C of the axle bracket 18, and the wedge portion 72F of the annular body 72 is inserted into the distal end side outer peripheral portion of the wheel side tube 12 and the axle bracket. It is assumed that the 18 tapered inner peripheral surfaces 18C are press-fitted into the intersection. The axle bracket 18 and the annular body 72 are press-fitted and held between the straight inner peripheral surface 18A on the opening side of the axle bracket 18 and the straight outer peripheral surface 72B on the proximal end side of the annular body 72.

According to the present embodiment, the following operational effects can be obtained.
(a) The front end surface of the wheel-side tube 12 is abutted against the bottom surface of the inner peripheral portion of the axle bracket 18 to fasten the wheel-side tube 12 and the axle bracket 18, thereby strengthening the axle bracket 18 and the wheel-side tube 12. By fastening, it is possible to prevent loosening of the threaded portion (male screw portion A and female screw portion B) of the axle bracket 18 and the wheel side tube 12.

  (b) In the vicinity of the opening of the inner peripheral portion of the axle bracket 18, there is provided gap clearance means 70 that eliminates the fitting gap formed by the inner peripheral portion of the axle bracket 18 and the outer peripheral portion on the front end side of the wheel side tube 12. As a result, the bending load acting on the wheel side tube 12 is passed through the clearance elimination means 70 while maintaining the abutting between the tip surface of the wheel side tube 12 and the bottom surface of the inner peripheral portion of the axle bracket 18 described above. Thus, the swinging movement of the wheel side tube 12 is prevented, and as a result, the occurrence of creep breakage near the threaded portion of the axle bracket 18 and the wheel side tube 12 can be avoided.

  (c) A wedge-shaped part 71 in which the gap eliminating means 70 is press-fitted into the fitting gap between the inner peripheral part of the axle bracket 18 and the outer peripheral part on the front end side of the wheel side tube 12 near the opening of the inner peripheral part of the axle bracket 18. It consisted of Thereby, the wedge-shaped part 71 is press-fitted by driving or the like, and the fitting gap formed by the inner peripheral portion of the axle bracket 18 and the outer peripheral portion on the front end side of the wheel side tube 12 can be reliably eliminated.

  (d) The tapered outer peripheral surface 72A of the annular body 72 constituting the wedge-shaped part 71 is press-fitted into the inner peripheral portion of the axle bracket 18, and the above (c) can be easily realized.

(Example 2)
The second embodiment is different from the first embodiment in that the annular body 72 constituting the wedge-shaped part 71 is replaced with an annular body 73 as shown in FIG. As shown in FIG. 8, the annular body 73 is different from the annular body 72 in that an octagonal outer peripheral surface 73A is provided at the base end (upper end) of the straight outer peripheral surface 72B on the base end side, and the straight outer peripheral surface 72B (tapered). The male threaded portion 73B is formed on the annular outer circumferential surface following the outer circumferential surface 72A. An internal thread portion 74 is provided on the straight inner peripheral surface 18B on the opening side of the axle bracket 18.

  A tool is engaged with the octagonal outer peripheral surface 73A of the annular body 73 of the wedge-shaped part 71, and the male threaded portion 73B is tightened into the female threaded portion 74 of the axle bracket 18, whereby the straight inner peripheral surface 72E of the annular body 73 is moved to the wheel side. The tapered outer peripheral surface 72A of the annular body 73 is press-fitted into the tapered inner peripheral surface 18C of the axle bracket 18 while being inserted into the distal end side outer peripheral portion of the tube 12, and the wedge portion 72F of the annular body 73 is inserted into the wheel side tube 12. It is assumed that the front end side outer peripheral portion and the tapered inner peripheral surface 18C of the axle bracket 18 are press-fitted.

  According to the present embodiment, in addition to the effects (a) to (c) of the first embodiment, the male screw portion 73B of the annular body 73 constituting the wedge-shaped part 71 is fastened to the female screw portion 74 of the axle bracket 18. Thus, the tapered outer peripheral surface 72A of the annular body 73 is press-fitted into the inner peripheral portion of the axle bracket 18, and the above-described (c) can be easily realized.

(Example 3)
The difference between the third embodiment and the first embodiment is that, as shown in FIGS. 9 and 10, the clearance eliminating means 70 is provided around the opening of the inner peripheral portion of the axle bracket 18 where the wheel side tube 12 is fitted. A slot 80 is provided over a certain range L along the axial direction from the open end of the bracket 18, and overhanging tightening portions 81 and 82 are provided opposite to both sides in the circumferential direction across the slot 80 of the axle bracket 18. is there. The bolt 83 inserted into the bolt insertion hole of the tightening portion 81 is screwed into the screw hole of the tightening portion 82 so that the opposing tightening portions 81 and 82 can be tightened.

  According to the present embodiment, in addition to the effects (a) and (b) of the first embodiment, the clearance eliminating means 70 is provided around the opening of the inner peripheral portion of the axle bracket 18 from the opening end of the axle bracket 18. A slot 80 is provided over a certain range along the axial direction, and tightening portions 81 and 82 are provided on both sides in the circumferential direction sandwiching the slot 80 of the axle bracket 18, and the opposing tightening portions 81 and 82 are bolted. It was possible to tighten with 83. Thereby, the slot 80 of the axle bracket 18 is tightened to reduce the diameter of the opening of the axle bracket 18, and the fitting gap formed by the inner peripheral portion of the axle bracket 18 and the outer peripheral portion on the front end side of the wheel side tube 12 is ensured. Can be eliminated.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration of the present invention is not limited to these embodiments, 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.

FIG. 1 is an overall cross-sectional view showing a front fork. FIG. 2 is a lower cross-sectional view of FIG. 3 is a cross-sectional view of the middle part of FIG. FIG. 4 is a top sectional view of FIG. FIG. 5 is a cross-sectional view showing the wheel side tube mounting structure of the first embodiment. FIG. 6 is a cross-sectional view showing the clearance elimination means. FIG. 7 is a cross-sectional view showing the wheel side tube mounting structure of the second embodiment. 8A and 8B show the clearance elimination means, where FIG. 8A is a plan view and FIG. 8B is a cross-sectional view. FIG. 9 is a cross-sectional view showing the attachment structure of the wheel side tube of the third embodiment. FIG. 10 is a plan view showing the clearance elimination means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Front fork 11 Car body side tube 12 Wheel side tube 18 Axle bracket 70 Gap clearance means 71 Wedge-shaped parts 72, 73 Annular body 72A Tapered outer peripheral surface 73B Male thread part 74 Female thread part 80 Slot 81, 82 Tightening part 83 Bolt

Claims (5)

The body side tube and the wheel side tube are slidably fitted, the outer peripheral part of the front end side of the wheel side tube is fitted to the inner peripheral part of the axle bracket, and the male thread part formed on the outer peripheral part of the front end side of the wheel side tube is In the front fork that is screwed into the female thread portion formed on the inner peripheral portion of the axle bracket,
The wheel side tube and the axle bracket are fastened by abutting the front end surface of the wheel side tube with the bottom surface of the inner periphery of the axle bracket.
A front fork characterized by comprising clearance elimination means for eliminating a fitting gap formed between the inner peripheral portion of the axle bracket and the outer peripheral portion on the front end side of the wheel side tube in the vicinity of the opening of the inner peripheral portion of the axle bracket.   The said clearance elimination means consists of a wedge-shaped part press-fitted in the fitting gap of the inner peripheral part of an axle bracket and the front end side outer peripheral part of a wheel side tube near the opening of the inner peripheral part of an axle bracket. Front fork.   The wedge-shaped part is provided with a tapered outer peripheral surface whose diameter decreases toward the front end on the front end side of the annular body, and the inner peripheral surface of the annular body is inserted into the outer peripheral portion on the front end side of the wheel side tube. The front fork according to claim 2, wherein a tapered outer peripheral surface of the front fork can be press-fitted into an inner peripheral portion of the axle bracket.   The front fork according to claim 3, wherein a male screw portion is formed on an annular outer peripheral surface following the tapered outer peripheral surface of the annular member, and the male screw portion can be tightened into a female screw portion formed on an inner peripheral portion of the axle bracket.   The clearance eliminating means is provided with a slit extending from the opening end of the axle bracket over a certain range along the axial direction around the opening of the inner peripheral portion of the axle bracket, and is opposed to both sides in the circumferential direction sandwiching the slit of the axle bracket. The front fork according to claim 1, wherein a tightening portion is provided, and the opposing tightening portion can be tightened with a bolt.

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