front fork

Abstract

The front fork (1) of the present invention comprises: a fork body (2), which has a vehicle body side tube (3) and an axle side tube (4); a cover body (5), which is installed on the vehicle body side tube (3); a cylinder (6), which is arranged in the axle side tube (4); a tubular rod (7), which can be inserted into the cylinder (6) movably in the axial direction; an electric appliance (8), which is accommodated in the cylinder (6); and an electric wire (9), which is inserted into the rod (7), passes through the cover (C) to be pulled out to the outside of the fork body (2), and is connected to the electric appliance (8); wherein, on the outer periphery of one side of the connecting tube (13b) or the rod (7), the connecting tube (13b) in the cover (C) and the rod (7) are restricted from axially moving toward the other side, and can be rotatably installed and connected to a connecting nut (27) screwed on the other side.

Description

Technical Field

[0001] The invention relates to a front fork. Background Art

[0002] Conventionally, as a front fork for supporting the front steering wheel of a suspended straddle-type vehicle, for example, a telescopic front fork is known, which includes: a fork body having a vehicle body side tube and an axle side tube movably inserted into the vehicle body side tube; and a shock absorber housed in the fork body that extends and contracts as the fork body extends and contracts.

[0003] The shock absorber comprises a cylinder, a piston that divides the cylinder into an expansion-side chamber and a compression-side chamber filled with hydraulic fluid, and a piston rod that is axially movable and inserted into the cylinder and connected to the piston. The shock absorber, for example, has the piston rod connected to a cap that closes the upper end of the body-side tube, while the cylinder is fixed to the lower end of the axle-side tube and housed within the fork body.

[0004] To improve the ride comfort of straddle-type vehicles, such front forks can adjust the damping force generated by the shock absorber using a controller located outside the fork. Forks with automatically adjustable damping force, for example, use electrorheological fluid or electromagnetic rheological fluid as the shock absorber's working fluid. By adjusting the current supplied to a coil housed in a piston, the viscosity of the working fluid is altered, thereby varying the damping force. Other front forks with automatically adjustable damping force, such as those disclosed in JP2014-190405A, incorporate a solenoid valve within the piston. Adjusting the amount of current flowing to the solenoid valve adjusts the damping force of the shock absorber.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: JP2014-190405A Summary of the Invention

[0008] Problems to be solved by the invention

[0009] As described above, front forks with automatic damping force adjustment incorporate damping force adjustment coils and solenoid valves within the shock absorber. These electrical components require power from an external power source or controller. Consequently, conventional front forks utilize a cylindrical piston rod and a cover with through-holes for wiring. While the wiring is sealed, it is routed through the piston rod and cover through-holes, leading to the fork body and connecting to an external power source.

[0010] However, in conventional front forks, a threaded portion at the upper end of the piston rod is threadedly connected to a threaded portion on the inner circumference of a cylindrical portion extending downward from the cover, and the piston rod is connected to the cover that holds the electrical wires. Therefore, when the cover and piston rod are threaded together, the cover must be rotated relative to the piston rod, which can cause the electrical wires to twist.

[0011] Therefore, an object of the present invention is to provide a front fork capable of preventing electric wires that supply power to internal electrical appliances from being twisted.

[0012] In order to achieve the above-mentioned purpose, the front fork in the solution of the present invention comprises: a telescopic fork body, which has a body side tube and an axle side tube and is telescopic; a cover, which is installed on the body side end of the body side tube; a cylinder, which is arranged in the axle side tube; a tubular rod, which can be inserted into the cylinder and moved freely in the axial direction, and one end of which is connected to the cover body; an electrical appliance, which is accommodated in the cylinder; and an electric wire, which is connected to the electrical appliance, inserted into the rod, and passes through the cover to be led out from the fork body to the outside; wherein the cover has a connecting tube connected to the rod, and is installed rotatably on the outer periphery of one side of the connecting tube and the rod while limiting its axial movement to the other side, and the connecting tube and the rod are connected by an annular connecting nut screwed on the outer periphery of the other side of the connecting tube and the rod.

[0013] In a front fork constructed in this manner, while the connecting nut is restricted from moving about the outer circumference of one of the connecting tube and the rod toward the other, it is mounted so as to be freely rotatable in the circumferential direction. Therefore, when the connecting nut is threaded onto the outer circumference of the other of the connecting tube and the rod, the connecting tube and the rod are drawn together and connected by the connecting nut without rotating. Therefore, in the aforementioned front fork, when attaching or detaching the cover to the rod, it is sufficient to rotate only the connecting nut without rotating the cover or the rod in the circumferential direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a longitudinal cross-sectional view of a front fork according to one embodiment of the present invention.

[0015] Figure 2 This is an enlarged longitudinal sectional view of the upper end portion of a front fork according to one embodiment of the present invention.

[0016] Figure 3 This is an enlarged plan view of a front fork according to an embodiment of the present invention as viewed from the axial direction.

[0017] Figure 4 This is an enlarged cross-sectional view of an adjuster portion of a front fork according to one embodiment of the present invention.

[0018] Figure 5 These are diagrams illustrating a procedure for disassembling a front fork according to one embodiment of the present invention.

[0019] Figure 6 This is an enlarged cross-sectional view of a connection portion between a connecting tube and a rod in a front fork according to a modified example of one embodiment of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be described below based on the embodiments shown in the drawings. Figure 1 and Figure 2 As shown, a front fork 1 according to one embodiment is constructed as follows: a telescopic fork body 2 having a body-side tube 3 and an axle-side tube 4 and being telescopic; a cap C mounted on the body-side end of the body-side tube 3; a cylinder 6 disposed in the axle-side tube 4; a piston rod 7, which is a tubular rod member and is inserted into the cylinder 6 so as to be freely movable in the axial direction and is connected to the cap C at one end; a solenoid 8, which is an electrical appliance and is accommodated in the cylinder 6; an electric wire 9, which is connected to the solenoid 8 and is inserted into the piston rod 7 and passes through the cap C to be led out from the fork body 2 to the outside; and a connecting nut 27, which connects the cap C and the piston rod 7. The body-side tube 3 of the front fork 1 is connected to the body of a suspension straddle-type vehicle (not shown), while the axle-side tube 4 is connected to the front wheel of the suspension straddle-type vehicle (not shown) and serves to suspend the straddle-type vehicle. Due to vibrations during travel of the suspension straddle-type vehicle, the body-side tube 3 and the axle-side tube 4 are relatively displaced along the axis A of the fork body 2, thereby expanding and contracting.

[0021] Hereinafter, each part of the front fork 1 according to an embodiment will be described in detail. Figure 1 and Figure 2 As shown, the front fork 1 includes a telescopic fork body 2 having a body-side tube 3 and an axle-side tube 4 slidably inserted into the body-side tube 3. When the fork body 2 vibrates, the axle-side tube 4 moves in and out of the body-side tube 3, causing the fork body 2 to extend and retract. While the fork body 2 in this embodiment is an inverted fork body with the axle-side tube 4 inserted into the body-side tube 3, an upright fork body with the body-side tube 3 inserted into the axle-side tube 4 may also be employed.

[0022] Next, the vehicle body side tube 3, which is the vehicle body side end of the fork body 2, is formed. Figure 2 A cap C is mounted on the upper end of the vehicle body side tube 3 to close the upper end opening of the vehicle body side tube 3. Figure 1 The lower middle end is blocked by the axle-side bracket 30. Furthermore, the cylindrical gap formed between the overlapping portions of the body-side tube 3 and the axle-side tube 4 is blocked by the annular seal member 20, which is attached to the lower end of the body-side tube 3 and in sliding contact with the outer periphery of the axle-side tube 4.

[0023] Thus, the interior of the fork body 2 becomes a sealed space, and a shock absorber D is housed within the fork body 2. The shock absorber D comprises a cylinder 6 housed within the axle-side tube 4, a piston 21 slidably inserted into the cylinder 6, and a piston rod 7, the lower end of which is connected to the piston 21 and the upper end of which protrudes out of the cylinder 6 and is connected via a cap C.

[0024] As previously described, the piston rod 7 is connected to the body-side tube 3 via the cap C, while the cylinder 6 is connected to the axle-side tube 4. Thus, the shock absorber D is mounted between the body-side tube 3 and the axle-side tube 4. As the fork body 2 expands or contracts, the piston rod 7 moves axially relative to the cylinder 6, thereby expanding or contracting.

[0025] In addition, in this embodiment, the piston rod 7 has a tubular piston retaining rod 7a as a small-diameter rod connected to the piston 21, and a tubular connector accommodating rod 7b as a large-diameter rod threadedly connected to the upper end of the piston retaining rod 7a, and is connected to the lower end of the cover C through a connecting nut 27.

[0026] The piston retaining rod 7a is provided with Figure 1 The threaded portion 7a1 on the outer periphery of the upper end and the sealing ring 7a2 installed on the outer periphery closest to the threaded portion 7a1, Figure 1 The lower end is connected to the piston 21.

[0027] In addition, the diameter of the connector receiving rod 7b is larger than that of the piston retaining rod 7a. Figure 1 The inner periphery of the lower end of the piston retaining rod 7a is provided with a threaded portion 7b1. Moreover, by making the threaded portion 7a1 at the upper end of the piston retaining rod 7a and the connector receiving rod 7b Figure 1 The piston retaining rod 7a and the connector receiving rod 7b are threadedly connected by screwing the threaded portion 7b1 on the inner circumference of the lower end of the piston retaining rod 7a into the piston retaining rod 7a. The piston retaining rod 7a and the connector receiving rod 7b are sealed by the aforementioned sealing ring 7a2. Alternatively, the piston retaining rod 7a and the connector receiving rod 7b may be formed as a single, integrated component.

[0028] Furthermore, the connector receiving rod 7b is Figure 1 In the upper end outer periphery of the connector receiving rod 7b, a flange 7b2 is provided. In addition, an annular stopper 28 is installed at a position spaced apart in the axial direction on the outer periphery of the connector receiving rod 7b, that is, on the outer periphery of the cylinder 6 side closer than the flange 7b2.

[0029] The connecting nut 27 comprises an annular nut portion 27a with a threaded groove on its inner circumference, and an annular extension portion 27b connected to the axial end of the nut portion 27a on the cylinder side. The inner diameter of the nut portion 27a is larger than the outer diameter of the flange 7b2, while the inner diameter of the extension portion 27b is smaller than the outer diameter of the flange 7b2 and slightly larger than the outer diameter of the connector receiving rod 7b.

[0030] Therefore, the fastening nut 27 has a stepped portion 27c. Figure 1 The inner diameter of the upper side is expanded in the middle and is aligned with the flange 7b2 of the connector receiving rod 7b. Figure 1 The lower surface of the connector accommodating rod 7b is opposite to the lower surface of the connector accommodating rod 7b. Furthermore, when the connector accommodating rod 7b, with the flange 7b2 facing upward, is inserted from above the connecting nut 27 onto the inner circumference of the connecting nut 27, the connecting nut 27 is fitted onto the outer circumference of the connector accommodating rod 7b, allowing for free axial movement, with the nut portion 27a facing upward. A stopper 28 is then attached and fixed to the outer circumference of the connector accommodating rod 7b, at a position at least the axial length of the extension portion 27b away from the flange 7b2.

[0031] The extension 27b of the connecting nut 27 is loosely fitted into the outer periphery of the connector receiving rod 7b, with the step 27c axially facing the flange 7b2 and the cylinder side end axially facing the stopper 28. Therefore, when the step 27c abuts against the flange 7b2, the extension 27b is restricted from moving toward the side opposite to the cylinder, and when Figure 1 When the lower end of the extension 27b contacts the stopper 28, the extension 27b is restricted from moving toward the cylinder. Therefore, the connecting nut 27 can move axially within the range between the flange 7b2 and the stopper 28, but will not fall off the connector receiving rod 7b. In addition, in this embodiment, the cross-sectional shape of the outer periphery of the extension 27b is hexagonal. Therefore, the user can grasp the extension 27b with a tool such as a wrench (not shown) and easily rotate the connecting nut 27. In addition, an annular groove 28a, for example, is formed on the outer periphery of the stopper 28, which serves as a mounting portion for mounting a C-shaped tool (not shown).

[0032] Next, the cylinder 6 is cylindrical. Figure 1 The upper end of the piston rod 7 is provided with an annular guide 22. The piston retaining rod 7a of the piston rod 7 is inserted into the inner side of the guide 22 so as to be movable in the axial direction. The guide 22 supports the piston rod 7 so as to be slidable and guides the piston rod 7 to move along the axial direction. Figure 1 Move up and down in the .

[0033] A liquid chamber L filled with a liquid such as hydraulic oil is formed within the cylinder 6. This liquid chamber L is divided into an extension-side chamber R1 and a compression-side chamber R2 by the piston 21. The extension-side chamber R1 referred to herein is the chamber that is compressed by the piston 21 when the shock absorber D is extended, of the two chambers divided by the piston 21. On the other hand, the compression-side chamber R2 is the chamber that is compressed by the piston 21 when the shock absorber D is contracted, of the two chambers divided by the piston 21. Furthermore, the piston 21 is connected to the lower end of the piston retaining rod 7a of the piston rod 7.

[0034] Thus, the shock absorber D in the front fork 1 of this embodiment is a single-rod type, with the piston rod 7 extending from one side of the piston 21 to the outside of the cylinder 6. However, the shock absorber D may also be a double-rod type, with the piston rods extending from both sides of the piston to the outside of the cylinder.

[0035] Furthermore, in addition to the cylinder 6, more specifically, the space between the shock absorber D and the fork body 2 serves as a reservoir R. The reservoir R stores the same liquid as that in the cylinder 6, and a gas chamber G is formed above the liquid level, which seals a gas such as air. Thus, the fork body 2 functions as the outer shell of a reservoir tank for storing a liquid different from the liquid in the cylinder 6.

[0036] In addition, although not shown in the figure, the liquid storage chamber R is connected to the compression side chamber R2, and is provided with a damping valve that applies resistance to the flow of liquid from the compression side chamber R2 to the liquid storage chamber R, and a check valve that only allows the flow of liquid from the liquid storage chamber R to the compression side chamber R2.

[0037] The piston 21 is also provided with a damping passage 21a, which connects the expansion-side chamber R1 and the compression-side chamber R2, and a solenoid valve SV, which resists the flow of liquid through the damping passage 21a. The solenoid valve SV includes a solenoid 8 as an electrical device and a valve body 25 driven by the solenoid 8.

[0038] In the front fork 1 according to this embodiment, although not shown in detail, the solenoid 8 includes, for example, a winding, a fixed core, a movable core inserted axially movable within the winding, and a spring biasing the movable core. Current flowing through the winding attracts the movable core toward the fixed core, applying thrust to the movable core. Furthermore, the solenoid 8 transmits the thrust applied to the movable core to the valve body 25. By adjusting the current flowing through the winding, the thrust applied to the valve body 25 can be adjusted. Therefore, the solenoid valve SV can adjust the resistance to the flow of fluid through the damping passage 21a according to the amount of current flowing through the solenoid 8. The solenoid valve SV can be a variable relief valve with adjustable valve opening pressure or a valve core with adjustable opening of the damping passage 21a. Alternatively, an orifice or damping valve can be provided in the damping passage 21a in series or parallel with the solenoid valve SV.

[0039] Then, the solenoid 8, an electrical device in the solenoid valve SV, receives power from an external power source (not shown) via an electrical wire 9 housed within the piston rod 7. The electrical wire 9 comprises an inner cable 9a, which is connected to the coil (not shown) of the solenoid 8 and inserted through the piston rod 7; and an outer cable 9b, which is connected to the inner cable 9a via a connector 9c, is retained by the cap C, and extends to the outside of the fork body 2.

[0040] One end of the outer cable 9b is connected to the inner cable 9a via a connector 9c, and the other end is provided with a coupler 9b1. This coupler 9b1 can be connected to an electric wire connected to an external power source (not shown). Therefore, when the coupler 9b1 is connected to the electric wire (not shown) on the external power source side, power can be supplied to the winding of the solenoid 8 via the electric wire 9.

[0041] Connector 9c includes a plug 9c1 internally equipped with a plug (not shown) that is electrically connected to the outer cable 9b, and a receptacle 9c2 internally equipped with contacts (not shown) that are electrically connected to the windings of solenoid 8 via the inner cable 9a. When plug 9c1 is inserted into receptacle 9c2, connector 9c maintains the plug inserted into the contacts, electrically connecting the inner cable 9a and the outer cable 9b. When plug 9c1 is removed from receptacle 9c2, contact between the plug and the contacts is severed, electrically isolating the inner cable 9a from the outer cable 9b. Alternatively, the outer cable 9b can be connected to receptacle 9c2 while the inner cable 9a is connected to plug 9c1.

[0042] The maximum width of connector 9c is smaller than the inner diameter of connector receiving rod 7b in piston rod 7, allowing connector 9c to be accommodated within connector receiving rod 7b and to be inserted and removed from above connector receiving rod 7b. Furthermore, inner cable 9a has sufficient length to allow connector 9c to be removed from the upper end of connector receiving rod 7b. When connector 9c is located within connector receiving rod 7b, it is accommodated in a relaxed state within connector receiving rod 7b.

[0043] Returning, if the fork body 2 extends and the shock absorber D extends, the piston 21 moves relative to the cylinder 6. Figure 1 As the shock absorber D moves upward in the cylinder 6, the expansion chamber R1 contracts and the compression chamber R2 expands. The fluid in the compressed expansion chamber R1 flows through the damping passage 21a of the piston 21 into the expanded compression chamber R2. Because the solenoid valve SV resists this fluid flow, the pressure in the expansion chamber R1 rises, causing the shock absorber D to generate a damping force that hinders the extension of the fork body 2. Furthermore, when the shock absorber D extends, the piston rod 7 retracts from the cylinder 6. This creates a fluid shortage within the cylinder 6 corresponding to the portion of the piston rod 7 that has retracted. This shortage is then supplied from the reservoir R through the check valve into the cylinder 6.

[0044] On the contrary, when the fork body 2 contracts and the shock absorber D contracts, the piston 21 moves relative to the cylinder 6. Figure 1As the damper D moves downward in the cylinder 6, the compression-side chamber R2 contracts and the extension-side chamber R1 expands. The fluid in the compressed compression-side chamber R2 moves through the damping passage 21a of the piston 21 into the expanded extension-side chamber R1. Furthermore, when the shock absorber D contracts, the piston rod 7 enters the cylinder 6. Excess fluid corresponding to the amount of piston rod 7 entering the cylinder 6 forms an excess. This excess fluid is then discharged from the compression-side chamber R2 through the damping valve into the reservoir chamber R. Because the solenoid valve SV resists the flow of fluid into the expansion-side chamber R1, and the damping valve resists the flow of fluid into the reservoir chamber R, the pressure in the compression-side chamber R2 rises, causing the shock absorber D to generate a damping force that hinders the contraction of the fork body 2.

[0045] Here, by adjusting the current supplied to the solenoid 8 in the solenoid valve SV, the resistance of the solenoid valve SV to the flow of the fluid can be adjusted. Therefore, the front fork 1 of this embodiment can adjust the damping force generated by the shock absorber D during extension and contraction.

[0046] Next, in the front fork involved in this embodiment, the cap C is configured to include: a cap body 5 that is screwed to the body side tube 3 and is used to close the opening of the body side tube 3; and a rod adapter 13 that is connected to the cap body 5 and connected to the piston rod 7.

[0047] The cover body 5 includes a cover portion 5a which is disc-shaped and is used to close the vehicle body side pipe 3. Figure 2 The opening at the upper end of the cylindrical portion 5b, which serves as the cover portion 5a in Figure 2 The fork side end of the lower end of the fork body protrudes inwardly while the center is consistent with the axis A; the wire hole 5c, which is formed from the cover portion 5a in Figure 2 While the opposite side end of the fork body at the upper end of the fork is connected to the cylindrical portion 5b, the center of the opening of the opposite side end of the fork of the cover portion 5a is eccentric from the axis A; the adjuster hole 5d is provided at a position of the cover portion 5a that is eccentric from the axis A and away from the position of the wire hole 5c, and passes through the cover portion 5a along the up and down directions as the axial direction; and the annular socket 5e stands upright from the outer peripheral side of the fork side end of the cover portion 5a toward the fork body side.

[0048] Furthermore, the cover body 5 is threadedly connected to the body side tube 3 by screwing a socket 5e having a threaded portion 5e1 on its outer periphery into a threaded portion 3a provided on the inner periphery of the upper end of the body side tube 3. The cover portion 5a of the cover body 5 closes the upper end opening of the body side tube 3 when the cover body 5 is screwed onto the inner periphery of the upper end of the body side tube 3. In addition, a sealing ring 26 is attached to the outer periphery of the socket 5e, that is, closer to the cover portion 5a than the threaded portion 5e1, and the sealing ring 26 is used to seal the gap between the cover body 5 and the body side tube 3. In addition, as Figure 3As shown, six notches 5a1 are provided at equal intervals along the circumferential direction on the outer periphery of the cover portion 5a to allow the cover body 5 to be gripped with a tool (not shown) when screwing the cover body 5 onto the vehicle body side tube 3. Furthermore, a threaded portion 5e2 is also provided on the inner periphery of the socket 5e.

[0049] The cylindrical portion 5b is a cylinder centered at the center thereof which coincides with the axis A of the fork body 2 of the cover portion 5a and is provided so as to extend from the cover portion 5a to the fork body 2. Figure 2 The fork body side end of the lower end in the fork body protrudes toward the fork body side.

[0050] In addition, if Figure 2 and Figure 3 As shown, the wire hole 5c is along the axial direction. Figure 2 The wire hole 5c extends vertically through the cover 5a and into the cylindrical portion 5b. Specifically, the wire hole 5c is composed of a large-diameter hole portion 5c1, which opens at the end opposite the fork body relative to the cover 5a and has a circular cross-section, and a small-diameter hole portion 5c2, which opens from the bottom of the large-diameter hole portion 5c1 and opens into the cylindrical portion 5b and has a smaller diameter than the large-diameter hole portion 5c1 and a circular cross-section.

[0051] like Figure 2 and Figure 3 As shown, the large diameter hole portion 5c1 is formed in a circular cross section, and the center of the opening is located at the center of the cover portion 5a. Figure 2 The opposite side end of the fork at the upper end is formed in a position deviated from the axis A and eccentrically relative to the cover portion 5a in the axial direction. In addition, the small-diameter hole portion 5c2 is a hole that is smaller than the large-diameter hole portion 5c1 and has a circular cross-section. It is formed along the axial direction of the cover portion 5a in a manner connected to the large-diameter hole portion 5c1 relative to the cover portion 5a. The center of the small-diameter hole portion 5c2 deviates from the axis A of the cover portion 5a and is eccentric. In the front fork 1 involved in this embodiment, the hole 5c for the electric wire is formed in the cover portion 5a so that when the cover body 5 is observed from the axial direction, a circle ( Figure 3 The circle shown by the single dotted line in the middle) M2 and the circle ( Figure 3 The circle (shown by the dashed line) M1 is contained within the range enclosed by the circle corresponding to the inner circumference of the large-diameter hole portion 5c1. Furthermore, the wire hole 5c can be positioned so that the center of the opening on the end of the cover portion 5a opposite the fork body is located eccentrically from the axis A. Therefore, it can be arranged in a direction inclined relative to the axis A and communicate with the interior of the cylindrical portion 5b.

[0052] Therefore, if the center of the opening of the wire hole 5c at the end of the cover 5a opposite the fork body is off-center relative to the axis A, the wire hole 5c can be positioned in the cover 5a with the axis A positioned inside the opening, or it can be positioned in the cover 5a with the axis A positioned outside the opening. Furthermore, the small-diameter hole portion 5c2 can be omitted, but its provision allows for a step portion 5c3 to be provided midway through the wire hole 5c, facing away from the fork body. Furthermore, the small-diameter hole portion 5c2 only needs to communicate with the large-diameter hole portion 5c1 and the interior of the cylindrical portion 5b. Therefore, it can be positioned so that only a portion of the small-diameter hole portion 5c2 overlaps with the large-diameter hole portion 5c1 when the cover body 5 is viewed from the axial direction. Furthermore, the cross-sections of the large-diameter hole portion 5c1 and the small-diameter hole portion 5c2 may be shapes other than circular, as long as the geometric center of the cross-section of the opening of the large-diameter hole portion 5c1 is located eccentrically relative to the axis A.

[0053] An annular guide 14 is fitted into the large diameter hole 5c1 of the wire hole 5c. The guide 14 comprises an inner seal ring 14a housed in an annular groove provided on the inner periphery along the circumferential direction; an outer seal ring 14b housed in an annular groove provided on the outer periphery along the circumferential direction; and a tapered portion 14c located on the inner periphery, i.e., closer to the inner seal ring 14a. Figure 2 The diameter of the fork body side on the lower side is expanded toward the fork body side.

[0054] Since the guide 14 is fitted into the electric wire hole 5 c whose center is eccentric from the axial center line A, it is also arranged at a position whose center is eccentric from the axial center line A with respect to the cover portion 5 a.

[0055] In this way, the inner portion of the large diameter hole 5c1, which is the opposite side of the fork body serving as the guide 14, is provided with a Figure 2 An annular seal holder 15 is pressed into the upper side of the guide member. The seal holder 15 expands the inner diameter of the guide member side so that it can hold the outer periphery of the annular seal 16 inserted into the inner peripheral side together with the guide member 14.

[0056] Thus, the outer cable 9b of the electrical wires 9 is inserted through the inner circumference of the guide 14 and the seal 16 fixed to the electrical wire hole 5c of the cover body 5. The outer circumference of the electrical wires 9 is sealed by the seal 16, which is retained by the inner circumference seal ring 14a on the inner circumference of the guide 14 and the seal holder 15. Furthermore, the gap between the guide 14 and the cover body 5 is sealed by the outer circumference seal ring 14b on the outer circumference of the guide 14.

[0057] The guide 14 not only holds the wires 9, the inner and outer sealing rings 14a and 14b, and positions the wires 9 relative to the cover body 5, but also bears the axial load generated by the press-fitting of the sealing bracket 15, thus performing multiple functions.

[0058] In addition, the outer cable 9b passes through the small diameter hole 5c2 and the cylindrical portion 5b. Figure 2 The outer cable 9b of the electric wire 9 extends from the upper end of the cylindrical portion 5b whose center is aligned with the axis A, and is led outward through the electric wire hole 5c, the center of which is eccentric with the axis A. Therefore, the electric wire 9 is led outward from a position eccentric with the axis A of the fork body 2 relative to the cover body 5.

[0059] Moreover, since the outer cable 9b of the electric wire 9 is bent near the position where it extends from the upper end of the cylindrical portion 5b and is inserted into the guide member 14, even if a force is applied to the outer cable 9b in the direction of pulling it out of the fork body, the portion (bent portion) 9b2 where the outer cable 9b is bent generates resistance, and the electric wire 9 is not easily pulled out.

[0060] Furthermore, an annular stopper ring 9d is provided near the outer periphery of the outer cable 9b, that is, near the lower end of the cylindrical portion 5b. Figure 2 Therefore, even if a large force is applied to the outer cable 9b in the direction of pulling out the fork body, the stopper ring 9d is in contact with the cylindrical portion 5b. Figure 2 The lower and middle ends abut against the outer cable 9b, limiting further displacement in the removal direction, thereby preventing the wire 9 from being pulled out of the fork body. Furthermore, the stopper ring 9d only needs to be secured to the outer periphery of the outer cable 9b so as not to pass through the cylindrical portion 5b. This facilitates attachment of the outer cable 9b to the cover body 5 after the outer cable 9b is attached to the cover body 5. For example, a binding band or the like can be used.

[0061] Furthermore, since the inner periphery of the guide member 14 includes a tapered portion 14c whose diameter increases toward the fork body side, the outer cable 9b bends along the surface of the tapered portion 14c, making it difficult to apply an excessive load to the bent portion 9b2 of the outer cable 9b. Moreover, when a force in the pulling direction is applied to the electric wire 9, the circumferential surface of the tapered portion 14c can support and protect the bent portion 9b2.

[0062] The adjuster hole 5d provided on the cover 5a is provided at a position eccentric from the axis A, that is, at a position away from the wire hole 5c, and penetrates the cover 5a in the vertical direction as the axial direction. The adjuster hole 5d is a hole with a circular cross section and serves as Figure 2 The inner diameter ratio of the fork body on the opposite side of the upper end is Figure 2 The lower part is small.

[0063] The rod adapter 13 and the cover body 5 together constitute the cover C and are connected to the piston rod 7. It includes: an outer tube 13a, which is screwed with the inner periphery of the socket 5e of the cover body 5; a connecting tube 13b, which is screwed with the inner periphery of the piston rod 7; Figure 2 a pair of arm portions 13c, 13c, which connect the outer cylinder 13a and the connecting cylinder 13b while being arranged in a 180-degree phase difference in the circumferential direction.

[0064] The outer cylinder 13a is Figure 2 The outer periphery of the middle upper end is provided with a threaded portion 13a1 that is screwed into the inner threaded portion 5e2 of the socket 5e. Figure 2 The outer periphery of the middle and lower end is provided with a threaded portion 13b1 which is screwed to the connecting nut 27 in the piston rod 7. The connector receiving rod 7b in the piston rod 7 is Figure 2 The upper end of the connecting rod 7b is inserted into the inner side of the lower end of the connecting tube 13b, and the connecting nut 27 fitted on the outer periphery of the connector receiving rod 7b is screwed onto the threaded portion 13b1 of the connecting tube 13b. Therefore, when the connecting nut 27 is screwed and screwed into the connecting tube 13b, the step portion 27c on the inner periphery of the connecting nut 27 and the screw thread of the connecting tube 13b are connected. Figure 2 A flange 7 b 2 is strongly clamped between the middle and lower ends. The flange 7 b 2 is provided on the outer periphery of the connector receiving rod 7 b , and the piston rod 7 is connected to the rod adapter 13 .

[0065] Furthermore, the outer tube 13a and the connecting tube 13b are not connected along the entire circumference, but are connected via arms 13c, 13c provided at intervals in the circumferential direction, so that two arc-shaped through holes 13d, 13d are formed between the outer tube 13a and the connecting tube 13b.

[0066] When the outer tube 13a of the rod adapter 13 constructed in this manner is inserted into the socket 5e of the cover body 5 and the threaded portion 13a1 and the threaded portion 5e2 are screwed together, the rod adapter 13 is connected to the cover body 5, and the front end of the cylindrical portion 5b of the cover body 5 is inserted and fitted into the connecting tube 13b. Figure 2 On the inner periphery of the upper end side.

[0067] In addition, if Figure 1As shown, a seal ring 31 attached to the inner circumference of the connecting tube 13b of the rod adapter 13 seals the connection between the cylindrical portion 5b and the connecting tube 13b, while a seal ring 7a2 seals the connection between the piston retaining rod 7a and the connector receiving rod 7b. Furthermore, the outer circumference of the wires 9 is sealed by the seal 16 and the inner circumference seal ring 14a, and the connection between the guide 14 and the cover body 5 is sealed by the outer circumference seal ring 14b. Thus, the space formed within the piston rod 7, the cylindrical portion 5b of the cover body 5, and the wire hole 5c is isolated from the outside, preventing liquid from flowing into this space from the fluid reservoir R and water and dust from outside the front fork from entering this space, thereby protecting the wires 9 housed therein.

[0068] Next, the adjuster 11 includes an operating portion 17 inserted into the adjuster hole 5d of the cover body 5; a plate 18 that moves vertically in response to operation of the operating portion 17; and a movable element 19 that is laminated on the plate 18 and fits onto the spring seat 12. The adjuster 11 can displace the movable element 19 along the axis A of the fork body 2 relative to the cover body 5 together with the spring seat 12 by operation of the operating portion 17.

[0069] The spring seat 12 can move relative to the cover body 5. Figure 1 The suspension spring 10 composed of a coil spring and mounted between the guide 22 is supported by the suspension spring 10. Figure 1 The suspension spring 10 exerts an elastic force that pushes the vehicle body side tube 3 and the axle side tube 4 away from each other, thereby urging the fork body 2 in the extension direction. Therefore, when the front fork 1 is installed between the front wheel and the vehicle body of a straddle-type vehicle (not shown), it elastically supports the vehicle body.

[0070] In addition, the spring seat 12 can move relative to the cover body 5 along the Figure 1 The axis A of the fork body 2 in the vertical direction moves, and the adjustment of the adjuster 11 changes the suspension spring 10. Figure 1 Therefore, in the front fork 1, the spring seat 12 is displaced in the vertical direction by operating the adjuster 11, and the support position of the upper end of the suspension spring 10 can be changed, so that the vehicle height of the suspension straddle type vehicle can be adjusted.

[0071] Next, the regulator 11 will be described in detail. Figure 2 As shown, the operating portion 17 includes a threaded shaft 17a, a Figure 2 The flange 17b at the upper end, the shaft 17c rising from the axis of the flange 17b, and the annular operating knob 17d installed on the outer periphery of the shaft 17c are rotatably accommodated in the adjuster hole 5d of the cover part 5a, except for the shaft 17c and the operating knob 17d.

[0072] A sealing ring 17 e is mounted on the outer periphery of the flange 17 b to seal between the operating portion 17 and the cover portion 5 a and prevent leakage of liquid from the liquid chamber R to the outside of the fork body 2 .

[0073] The threaded shaft 17a, flange 17b, and shaft portion 17c are formed from a single component. The outer circumference of shaft portion 17c and the inner circumference of operating knob 17d can be any shape other than circular, such as a double-sided width or a hexagonal shape, as long as they match. Therefore, when operating knob 17d is engaged with the outer circumference of shaft portion 17c, relative rotation of shaft portion 17c and operating knob 17d in the circumferential direction is prevented.

[0074] In addition, if Figure 3 As shown, the outer periphery of the operating knob 17d is provided with cutouts 17d1 arranged at equal intervals at six locations around it to facilitate gripping with a wrench, and the outer shape of the operating knob 17d is larger than the adjuster hole 5d and cannot enter the adjuster hole 5d. In addition, the operating knob 17d is prevented from falling off the shaft portion 17c by a C-shaped pin not shown in the figure installed on the outer periphery of the shaft portion 17c. The flange 17b is accommodated in the adjuster hole 5d, and its outer diameter is larger than the inner diameter of the opposite side of the fork body with the smallest diameter in the adjuster hole 5d, cooperating with the operating knob 17d and clamping the material of the cover portion 5a. Therefore, the operating portion 17 is restricted in its axial direction by the operating knob 17d and the flange 17b. Figure 2 As described above, when the operation knob 17d is rotated, the entire operation portion 17 rotates in the circumferential direction.

[0075] Furthermore, a disc-shaped plate 18 is screwed onto the threaded shaft 17a of the operating portion 17. Figure 4 As shown, the plate 18 has a through hole 18a through which the cylindrical portion 5b of the cover body 5 is inserted in the center, and a threaded hole 18b threadedly engaged with the outer periphery of the threaded shaft 17a, and is fitted to the inner periphery of the outer cylinder 13a of the rod adapter 13 so as to be axially movable.

[0076] Therefore, since the plate 18 is stopped by the outer tube 13a of the rod adapter 13, when the operating portion 17 is rotated, the plate 18 moves in the outer tube 13a of the rod adapter 13 along the axis A of the fork body 2, that is, Figure 2 In addition, the outer shape of the plate 18 is circular, but as long as the rotation is stopped by the rod adapter 13, it can also be a shape other than a circle.

[0077] In addition, the movable member 19 comprises: a cylindrical portion 19a, which abuts against the plate 18; and a pair of protruding pieces 19b, 19b, which stand up from the side end of the fork body, the side end of the fork body being the cylindrical portion 19a in Figure 2The protruding piece 19b, 19b has an arc-shaped cross section, extending axially from the cylindrical portion 19a to the Figure 2 The lower middle portion extends through the arms 13 c, 13 c of the rod adapter 13 and protrudes toward the outside of the rod adapter 13 through the through holes 13 d, 13 d.

[0078] The spring seat 12 is annular, with a diameter on the upper side being larger than that on the lower side, and a step portion 12a is formed in the middle of the axial direction. Figure 2 At the middle upper end, the inner periphery on the large diameter side is fitted with the outer side surface of the front end of the protruding piece 19 b of the movable member 19 , and is connected to the movable member 19 .

[0079] In the adjuster 11 constructed in this manner, when the plate 18 is moved up and down by rotating the operating portion 17, the movable member 19 and the spring seat 12 connected to the movable member 19 are also displaced in the vertical direction together with the plate 18. Therefore, by rotating the operating portion 17, the plate 18 can be moved up and down. Figure 1 The support position of the suspension spring 10 of the spring seat 12 is adjusted in the vertical direction, and the vehicle height of the suspension straddle-type vehicle using the front fork 1 can be adjusted. In addition, a sufficient gap is provided between the cover portion 5a of the cover body 5 and the connecting tube 13b of the rod adapter 13 to allow the plate 18 to move. This allows the plate 18 to not interfere with the cover portion 5a and the rod adapter 13 when the plate 18 is moved vertically within the aforementioned vehicle height adjustment range.

[0080] The front fork 1 is constructed as described above. When performing maintenance work, the cover body 5 is removed from the vehicle body side tube 3 and the vehicle body side tube 3 is slid toward the axle side tube 4 to expose the suspension spring 10 to the outside. Figure 5 As shown, after the suspension spring 10 is compressed until its upper end is positioned below the stopper 28, a C-shaped tool W is fitted into the annular groove 28a of the stopper 28. The tool W can be fitted into the annular groove 28a of the stopper 28 and has an outer diameter larger than that of the suspension spring 10. Therefore, it supports the upper end of the suspension spring 10 in place of the spring seat 12 and maintains the suspension spring 10 in a compressed state. The illustrated tool W is merely an example; any tool that can be attached to and detached from the stopper 28 and that supports the upper end of the suspension spring 10 may be used. Therefore, the shape and structure of the tool W can be modified as appropriate.

[0081] In this manner, when the upper end of the suspension spring 10 is supported by the tool W, the connecting nut 27 is positioned above the upper end of the suspension spring 10, and the connecting nut 27 can be operated from the outside without being interfered with by the suspension spring 10. Furthermore, by gripping the outer periphery of the extension portion 27b with a tool such as a wrench and rotating the connecting nut 27, the connecting nut 27 can be easily removed from the threaded portion 13b1, and the cap C can be removed from the piston rod 7.

[0082] Next, pull the connector 9c out of the connector receiving rod 7b, remove the plug 9c1 of the connector 9c from the socket 9c2, separate the inner cable 9a from the outer cable 9b, and completely remove the outer cable 9b and the cover C from the fork body 2. This allows the cover C to be completely removed from the body-side tube 3 without being interfered with by the wires 9. Removing the cover C from the body-side tube 3 completes the disassembly process, fully opening the upper end of the body-side tube 3, and allowing maintenance work such as replacement of the suspension spring 10 and seals within the fork body 2, and replacement or refilling of the hydraulic oil in the shock absorber D and the reservoir R.

[0083] After maintenance is complete, the cover C and outer cable 9b are installed on the fork body 2. The plug 9c1 and socket 9c2 are connected, and the inner cable 9a is connected to the outer cable 9b. Next, after inserting the upper end of the connector receiving rod 7b of the piston rod 7 into the connecting tube 13b of the cover C, the connecting nut 27 is threaded onto the threaded portion 13b1 provided on the outer circumference of the connecting tube 13b. The flange 7b2 of the connector receiving rod 7b is then clamped between the connecting nut 27 and the lower end of the connecting tube 13b, connecting the piston rod 7 to the cover C. During this operation of connecting the piston rod 7 to the cover C, the tool W is mounted on the stopper 28, and the upper end of the suspension spring 10 is supported by the tool W.

[0084] Then, the tool W is removed, and the upper end of the suspension spring 10 is supported on the spring seat 12. In this state, the body side tube 3 is rotated and the body side tube 3 is screwed onto the threaded portion 5e1 on the outer periphery of the cover body 5. The cover C is then connected to the body side tube 3, and the assembly of the front fork 1 is completed.

[0085] As described above, when the cap C is attached to or detached from the piston rod 7, the cap C and the piston rod 7 do not rotate; only the connecting nut 27 rotates. Therefore, the electric wire 9, which is attached to the cap C and inserted into the piston rod 7, does not rotate when the cap C is attached to or detached from the piston rod 7, and thus does not twist at all.

[0086] As described above, the front fork 1 of this embodiment comprises: a telescopic fork body 2 having a body-side tube 3 and an axle-side tube 4 and being extendable and retractable; a cap C mounted on the body-side end of the body-side tube 3; a cylinder 6 disposed within the axle-side tube 4; a cylindrical piston rod (rod member) 7 inserted into the cylinder 6 so as to be freely movable in the axial direction and connected at one end to the cap body 5; a solenoid (electrical device) 8 housed in the cylinder 6; and an electric wire 9 connected to the solenoid (electrical device) 8 and inserted through the axle-side tube 4. The piston rod (rod member) 7 is inserted into the cover C and is led out from the fork body 2 to the outside; wherein, the cover C has a connecting tube 13b connected to the piston rod (rod member) 7, and can be installed rotatably while limiting its axial movement toward the other side at a predetermined position on the outer periphery of the connecting tube 13b and the piston rod (rod member) 7. The connecting tube 13b and the piston rod (rod member) 7 are connected by an annular connecting nut 27 screwed on the outer periphery of the other side of the connecting tube 13b and the piston rod (rod member) 7.

[0087] In the front fork 1 constructed in this manner, although the connecting nut 27 is restricted from moving toward the other side on the outer periphery of one side of the connecting tube 13b and the piston rod (rod member) 7, it is installed in a manner so that it can rotate freely in the circumferential direction. Therefore, when the connecting nut 27 is screwed onto the outer periphery of the other side of the connecting tube 13b and the piston rod (rod member) 7, the connecting tube 13b and the piston rod (rod member) 7 are pulled together and connected by the connecting nut 27 without rotating.

[0088] Therefore, in the front fork 1 configured in this manner, when attaching or detaching the cap C from the piston rod (rod) 7, it is sufficient to rotate only the connecting nut 27 without rotating the cap C or the piston rod (rod) 7 in the circumferential direction. Therefore, according to the front fork 1 of this embodiment, when attaching or detaching the cap C from the piston rod (rod) 7, the electric wire 9 that supplies power to the internal solenoid (electrical device) 8 can be prevented from twisting while being inserted into the cap C and the piston rod (rod) 7.

[0089] Furthermore, in the front fork 1 according to the present embodiment, the connecting nut 27 is rotatably mounted on the outer periphery of the piston rod (rod member) 7 while being restricted in movement toward the connecting tube 13b by the flange 7b2, and is screwed into the threaded portion 13b1 on the outer periphery of the connecting tube 13b. Alternatively, the connecting nut 27 can be rotatably mounted on the outer periphery of the connecting tube 13b while being screwed into the outer periphery of the piston rod (rod member) 7 while being restricted in movement toward the piston rod (rod member) 7. Furthermore, the predetermined position of the connecting nut 27 on the outer periphery of one of the connecting tube 13b and the piston rod (rod member) 7, which restricts movement of the connecting tube 13b and the piston rod (rod member) 7 toward the other side, is set at a position where the connecting nut 27 can be screwed into the outer periphery of the other of the connecting tube 13b and the piston rod (rod member) 7. In this manner, the connecting nut 27 restricts movement of the connecting tube 13b and the piston rod (rod) 7 toward the other side by means of the outer periphery of one side of the connecting tube 13b and the piston rod (rod member) 7, and can be threadedly engaged with the outer periphery of the other side of the connecting tube 13b and the piston rod (rod member) 7, thereby drawing the connecting tube 13b and the piston rod (rod member) 7 closer together and connecting them. In the case of the front fork 1 according to this embodiment, a flange 7b2 is provided on the outer periphery of the connector receiving rod 7b. When the step portion 27c of the connecting nut 27 abuts the flange 7b2, the connecting nut 27 restricts movement toward the connecting tube 13b. The predetermined position is determined by the position of the flange 7b2. In addition, the connecting nut 27 only needs to limit the movement of one side of the connecting tube 13b and the piston rod (rod member) 7 toward the other side of the connecting tube 13b and the piston rod (rod member) 7 at a predetermined position. Therefore, when the connecting tube 13b and the piston rod (rod member) 7 are not connected, it can also be allowed to move in a direction away from the connecting tube 13b or the other side of the piston rod (rod member) 7, and can also be installed at a predetermined position relative to a predetermined position of one side of the connecting tube 13b and the piston rod (rod member) 7 so as to be freely rotatable in the circumferential direction in an axially fixed state.

[0090] Furthermore, in the front fork 1 according to this embodiment, the piston rod (rod) 7 is cylindrical, and the electric wire 9 is led out of the cylinder 6 through the piston rod (rod) 7. Therefore, according to the front fork 1 according to this embodiment, the electric wire 9 does not interfere with the relative displacement of the piston rod (rod) 7 with respect to the cylinder 6, and the fork body 2 can smoothly extend and retract.

[0091] Furthermore, in the front fork 1 according to this embodiment, the connecting tube 13b is fitted into the outer periphery of the cap-side end of the piston rod (rod member) 7. The piston rod (rod member) 7 has a flange 7b2 that abuts the end of the connecting tube 13b. The connecting tube 13b has a threaded portion 13b1 on its outer periphery. The connecting nut 27 is threadedly engaged with the threaded portion 13b1, and together with the connecting tube 13b, the flange 7b2 is clamped to connect the cap C and the piston rod (rod member) 7. According to the front fork 1 constructed in this manner, since the piston rod (rod member) 7 is fitted into the connecting tube 13b, the connection portion of the connecting nut 27 can be provided with sufficient strength to withstand bending moments, thereby improving the practicality of the front fork 1.

[0092] In addition, in the above embodiment, the upper end of the piston rod (rod member) 7 is inserted into the inner periphery of the connecting tube 13b, but if Figure 6 As shown, when the connecting tube 13b is inserted into the inner circumference of the upper end of the piston rod (rod member) 7, a flange 13b2 may be provided on the outer circumference of the connecting tube 13b, and a connecting nut 27 may be mounted on the outer circumference of the connecting tube 13b. Furthermore, a threaded portion 7b3 for threading the connecting nut 27 may be provided on the outer circumference of the connector receiving rod 7b. Specifically, the connecting tube 13b of the cap C is fitted into the inner or outer circumference of the cap-side end of the piston rod (rod member). A flange is provided on one end of the connecting tube 13b and the cap-side end of the piston rod (rod member) so as to abut against the other end. A threaded portion is provided on the outer circumference of the other end of the connecting tube 13b and the cap-side end of the piston rod (rod member). The connecting nut 27 is threadedly engaged with the threaded portion, and the flange is clamped between the connecting nut 27, the connecting tube 13b, and the other end of the piston rod (rod member) 7.

[0093] However, when the connecting tube 13b is inserted into the inner periphery of the upper end of the piston rod (rod) 7, the outer diameter of the connector receiving rod 7b becomes larger, and the outer diameters of the suspension spring 10, the vehicle body side tube 3 and the axle side tube 4 become larger. Figure 1 and Figure 2 When a structure is adopted in which the connector receiving rod 7 b is inserted into the inner periphery of the connecting tube 13 b as in the front fork 1 shown in the figure, the outer diameter of the front fork 1 can be reduced in size.

[0094] In the front fork 1 of this embodiment, the connecting nut 27 includes an annular nut portion 27a that is threadedly engaged with the threaded portion 13b1, and an annular extension portion 27b that is connected to one axial end of the nut portion 27a and is axially movably mounted on the outer periphery of the cap-side end of the piston rod (rod member) 7. The outer periphery of at least a portion of the extension portion 27b is configured to be gripped with a tool. With this configuration, the connecting nut 27 can be miniaturized, and the outer diameters of the suspension spring 10, the body side tube 3, and the axle side tube 4 can be reduced, thereby minimizing the outer diameter of the front fork 1. Furthermore, if the outer periphery of the nut portion 27a is configured to be gripped with a tool, the connecting nut 27 only needs to include the nut portion 27a and the stepped portion 27c that faces the flange 7b2, and does not need to include the extension portion 27b. In this way, when the outer circumference of the nut portion 27a is a shape that can be grasped by a tool, since the connecting nut 27 is screwed onto the outer circumference of the components arranged on the outer circumference of the connecting tube 13b and the piston rod (rod member) 7, it is necessary to ensure the wall thickness of the nut portion 27a, so the outer shape of the nut portion 27a is enlarged, and thus the outer shape of the front fork 1 is also enlarged. Therefore, in terms of miniaturization, it is advantageous to adopt a structure of the front fork 1 with an extension portion 27b that can be grasped by a tool. In addition, the outer circumference of the extension portion 27b of the connecting nut 27 can be a shape that can be grasped by a tool along its entire axial length, or it can be a shape that can be grasped by a tool only in a portion of the outer circumference. In addition, the outer circumference of the extension portion 27b is not limited to a hexagonal shape as long as it is a shape suitable for the tool used to rotate the connecting nut 27.

[0095] In addition, in the front fork 1 involved in this embodiment, the piston rod (rod member) 7 includes: a cylindrical piston retaining rod (small diameter rod member) 7a, which enters and exits the cylinder 6; a connector accommodating rod (large diameter rod member) 7b, one end of which is connected to the cylinder opposite side end of the piston retaining rod (small diameter rod member) 7a and has an inner diameter larger than that of the piston retaining rod (small diameter rod member) 7a; the electric wire 9 includes: an inner cable 9a, which is accommodated in the piston retaining rod (small diameter rod member) 7a; an outer cable 9b, which is accommodated in the connector accommodating rod (large diameter rod member) 7b and passes through the cover C and is led out to the outside of the fork body 2; a connector 9c, which is accommodated in the connector accommodating rod (large diameter rod member) 7b and connects the inner cable 9a and the outer cable 9b; wherein the other end of the connector accommodating rod (large diameter rod member) 7b is connected to the cover C by a connecting nut 27.

[0096] With the front fork 1 constructed in this manner, the electrical wires 9 can be separated into the inner cable 9a and the outer cable 9b by the connector 9c. This allows the cover C and the outer cable 9b to be completely removed from the fork body 2, simplifying maintenance. Furthermore, since the bulky connector 9c is housed within the connector housing rod 7b outside the cylinder 6, and only the piston retaining rod 7a, with its smaller outer diameter, is inserted into the cylinder 6, the pressure-bearing area of ​​the piston 21 is ensured without increasing the diameter of the cylinder 6. This allows for sufficient extension-side damping force while avoiding an increase in the size of the front fork 1. Furthermore, in the front fork 1 according to this embodiment, the electrical wires 9 are connected to the inner cable 9a and the outer cable 9b by the connector 9c, making maintenance of the front fork 1 easier. However, a configuration in which the electrical wires 9 are not split midway, with one end connected to the solenoid (electrical device) 8 and the other end extending through the electrical wire hole 5c in the cover body 5, is also possible.

[0097] Furthermore, the front fork 1 according to this embodiment includes: a suspension spring 10, which is disposed on the outer periphery of the piston rod (rod) 7 and housed within the fork body 2, urging the fork body 2 in the extension direction; and a stopper 28, which is disposed on the outer periphery of the piston rod (rod) 7, closer to the cylinder 6 side than the flange 7b2, and restricts movement of the extension portion 27b of the connecting nut 27 toward the cylinder 6. The stopper 28 has an annular groove (mounting portion) 28a for mounting a tool W for supporting the upper end of the suspension spring 10. With this configuration, the upper end of the suspension spring 10 is supported by the tool W mounted on the stopper 28. Rotation of the connecting nut 27 is not hindered by the suspension spring 10, thereby facilitating attachment and detachment of the cap C relative to the piston rod (rod) 7. The tool W only needs to be mountable on the stopper 28 and support the upper end of the suspension spring 10 to maintain the suspension spring 10 in a retracted state. Therefore, in the front fork 1 involved in this embodiment, since the tool W is a C-shaped circular plate, the mounting portion of the stopper 28 is an annular groove 28a to enable insertion and retention of the tool W, but it can also be appropriately designed according to the shape and structure of the tool W.

[0098] The front fork 1 according to this embodiment includes a suspension spring 10 housed within the fork body 2 and biasing the fork body 2 in an extension direction; and an adjuster 11 capable of adjusting the support position of a spring seat 12 supporting the suspension spring 10. The electric wire 9 is pulled out of the fork body 2 at a position eccentric from the axis A of the fork body 2 in the cover body 5. An operating portion 17 of the adjuster 11 is provided at a position eccentric from the axis A of the fork body 2 in the cover body 5, i.e., away from the electric wire 9. In the front fork 1 thus configured, the operating portion 17 of the adjuster 11 and the electric wire 9 are positioned eccentric from the axis A of the fork body 2 relative to the cover body 5. The operating portion 17 is not positioned around the outer periphery of the electric wire 9. This allows the operating portion 17 to be miniaturized regardless of the diameter of the electric wire 9. This prevents interference with the electric wire 9 when the user operates the operating portion 17. Furthermore, the electric wire 9 and the operating portion 17 can be relatively freely positioned on the cover body 5. Therefore, according to the front fork 1 of this embodiment, even if the solenoid (electrical device) 8 is provided therein, the operating portion 17 of the adjuster 11 can be miniaturized without the electric wire 9 interfering with the operation of the operating portion 17 , and the degree of design freedom can be improved.

[0099] Furthermore, in the front fork 1 involved in this embodiment, the cover body 5 includes: a disc-shaped cover portion 5a; a cylindrical portion 5b, which protrudes from the fork-side end of the cover portion 5a toward the inside of the fork body and has its center aligned with the axis A; a hole 5c for electric wires, which extends from the opposite side end of the fork body of the cover portion 5a into the cylindrical portion 5b, and the center of the opening of the opposite side end of the fork of the cover portion 5a is eccentric with the axis A; a guide member 14 that is annular and accommodated in the hole 5c for electric wires and has the electric wire 9 inserted through the inner circumference, and the electric wire 9 is bent after being inserted into the cylindrical portion 5b and the guide member 14. With this structure, the guide 14 positions the wire 9 relative to the cover body 5 in the wire hole 5c, which has an opening larger than the wire 9. This facilitates insertion of the wire 9 into the wire hole 5c. Furthermore, because the guide 14 and the cylindrical portion 5b bend the wire 9, even if a force is applied to pull the wire 9 out of the cover body 5, the bent portion 9b2 of the wire 9 acts as resistance, preventing the wire 9 from being pulled out of the cover body 5. Furthermore, the use of the guide 14 facilitates positioning the wire 9 at an offset position from the axis A at the end of the cover body 5 opposite the fork body, and allows the wire 9 to be bent. Furthermore, because the center of the cylindrical portion 5b coincides with the axis A, the wire 9 can be easily inserted into the cylindrical portion 5b when being pulled out of the cylinder 6 through the piston rod (rod) 7, simplifying assembly of the front fork 1.

[0100] Alternatively, if the opening of the wire hole 5c on the side opposite the fork body is offset from the axis A relative to the cover body 5, the guide 14 can be eliminated. Furthermore, in the front fork 1 according to this embodiment, the wire hole 5c is axially continuous within the cylindrical portion 5b. Specifically, the wire hole 5c is formed in the cover portion 5a so that, when the cover body 5 is viewed axially, the circle corresponding to the inner circumference of the small-diameter hole 5c2 and the circle corresponding to the inner circumference of the cylindrical portion 5b are contained within the area enclosed by the circle corresponding to the inner circumference of the large-diameter hole 5c1. This axial continuity of the wire hole 5c within the cylindrical portion 5b eliminates the need to bend the wire 9 when inserting it through the wire hole 5c and the cylindrical portion 5b of the cover body 5, thereby facilitating installation of the wire 9 on the cover body 5.

[0101] Furthermore, the front fork 1 according to this embodiment includes an outer peripheral seal ring 14b that seals between the outer periphery of the guide member 14 and the cover body 5, and an annular seal 16 that is laminated on the guide member 14 and seals between the guide member 14 and the electrical wires 9. This seal maintains the seal between the electrical wires 9 and the cover body 5 even when the electrical wires 9 are pulled outward from the electrical wire hole 5c in the cover body 5, preventing water, dust, and the like from entering the interior of the fork body 2. Alternatively, an annular groove may be provided on the inner wall of the electrical wire hole 5c in the cover body 5, and the outer peripheral seal ring 14b may be mounted in this annular groove and retained on the cover body 5.

[0102] Furthermore, the front fork 1 of this embodiment includes an inner circumferential seal ring 14a that seals the inner circumference of the guide 14 and the outer circumference of the electric wire 9. With this configuration, the outer circumference of the electric wire 9 is sealed not only by the seal 16 but also by the inner circumferential seal ring 14a. This allows the interior of the fork body 2 to be tightly sealed, effectively preventing water from entering the interior of the fork body 2 even when a suspension straddle-type vehicle equipped with the front fork 1 is cleaned using a high-pressure washer.

[0103] Furthermore, in the front fork 1 according to the present embodiment, the guide 14 includes a tapered portion 14c on the inner periphery of the fork body side that expands toward the fork body side. According to the front fork 1 constructed in this manner, since the electric wire 9 is bent along the surface of the tapered portion 14c, it is not easy to apply an excessive load to the bent portion 9b2 of the electric wire 9. Moreover, when a force in the pulling direction is applied to the electric wire 9, the bent portion 9b2 can be supported by the peripheral surface of the tapered portion 14c, and the electric wire 9 can be protected. Furthermore, in the front fork 1 according to the present embodiment, the guide 14 includes the inner peripheral sealing ring 14a and the outer peripheral sealing ring 14b. Regardless of the axial length ( Figure 2The vertical length of the guide 14 will be longer, so when the inner periphery does not have the tapered portion 14c, the angle of the bent portion 9b2 of the wire 9 relative to the direction of the axial centerline A becomes larger. In other words, even if the guide 14 maintains the inner sealing ring 14a and the outer sealing ring 14b to lengthen the axial length of the guide 14, the angle of the bent portion 9b2 of the wire 9 can be softened and the burden on the bent portion 9b2 can be reduced by providing the tapered portion 14c on the inner periphery of the guide 14. In addition, the tapered portion 14c in the guide 14 can be omitted. In the case where it is necessary to soften the angle of the bent portion 9b2, the inner diameter of the fork body side of the guide 14 can be increased instead of the tapered portion 14c, so that the support position of the wire 9 in the guide 14 is as close as possible. Figure 2 Above the middle.

[0104] Furthermore, in the front fork 1 according to this embodiment, a stopper ring 9d is provided on the outer periphery of the electric wire 9, facing the fork body-side end of the cylindrical portion 5b. With this configuration, even if a large force is applied to the electric wire 9 in the direction of removal from the fork body 2, the stopper ring 9d abuts against the cylindrical portion 5b, limiting further displacement of the electric wire 9 in the removal direction and preventing the electric wire 9 from being removed from the fork body 2.

[0105] As described above, the adjuster 11 in the front fork 1 according to this embodiment includes: an operating portion 17; a plate 18 threadedly engaged with the screw shaft 17a in the operating portion 17; and a movable member 19 that abuts the plate 18 and engages with the spring seat 12. This configuration of the adjuster 11 allows the operating portion 17 to be optimally positioned eccentrically from the axis A of the fork body 2 relative to the cover body 5, i.e., at a position that does not interfere with the electrical wires 9. Furthermore, the adjuster 11 can also employ other configurations, as long as it allows for changing the support position of the spring seat 12, which includes the operating portion and supports the upper end of the suspension spring 10. For example, in the case where the operating portion 17 of the adjuster 11 is screwed to the cover body 5 and moves vertically by rotation, the plate 18 may be eliminated and the lower end of the operating portion 17 may directly abut against the upper end of the movable member 19. Alternatively, the plate 18 may be eliminated and a cylindrical nut, which is locked in rotation, may be screwed onto the outer circumference of the threaded shaft 17a of the operating portion 17 and the lower end of the nut may abut against the movable member 19. In this manner, if the adjuster 11 adopts a structure that does not interfere with the electric wire 9, the design of the adjuster 11 can be modified as appropriate.

[0106] Furthermore, when the adjuster 11 is not provided, the cap C need not be constructed from multiple components, namely the cap body 5 and the rod adapter 13. Although not shown, the cap C may be constructed from a single component, comprising a cap that can be mounted on the open end of the vehicle body side tube 3 and a cylindrical connecting tube extending from the cap toward the rod. Therefore, the cap C may be constructed from a single component, regardless of the presence or absence of an adjuster, or from three or more components, if it can be constructed from a single component.

[0107] In addition, in the front fork 1 of this embodiment, the electrical appliance is configured as a solenoid 8. However, the electrical appliance is not limited to a solenoid 8. When the shock absorber D utilizes an electrorheological fluid or a magnetorheological fluid damper, and a coil is used to change the viscosity, the electrical appliance can also be a coil. Furthermore, in addition to being used to adjust the damping force of the shock absorber D within the front fork 1, the electrical appliance can also be a sensor-type device for detecting the pressure within the shock absorber D and the telescopic displacement of the fork body 2. It can also be a device composed of a damping force adjustment device and a sensor-type device. That is, the present invention is applicable to a front fork 1 in which an electrical appliance is housed within the cylinder 6. Furthermore, if the electrical appliance is displaced relative to the cylinder 6, but at least a portion of the electrical appliance remains inserted within the cylinder 6, this state is consistent with the definition of housing the electrical appliance within the cylinder 6. Furthermore, the rod is not limited to the piston rod 7 that retains the piston; it can also be a rod that simply moves in and out of the cylinder.

[0108] While the preferred embodiments of the present invention have been described in detail above, modifications, variations, and alterations may be made without departing from the scope of the claims.

[0109] This application claims priority based on Japanese Patent Application No. 2021-021556 filed with the Japan Patent Office on February 15, 2021, the entire contents of which are incorporated herein by reference.

Claims

1. A front fork, It has: a telescopic fork body having a body side tube and an axle side tube and being telescopic; a cover mounted on a body side end of the body side tube; a cylinder disposed in the axle side tube; a cylindrical rod, which is axially movable and inserted into the cylinder, and one end of which is connected to the connecting tube of the cover; an electrical appliance housed in the cylinder; an electric wire, which is connected to the electrical appliance, inserted into the rod, and passes through the cover to be led out from the fork body to the outside; and An annular connecting nut is rotatably mounted on the outer periphery of one of the connecting tube and the rod, and restricts the axial movement of the connecting tube and the rod toward the other side at a position where the connecting nut is threadedly engaged with the outer periphery of the other side of the connecting tube and the rod. The connecting tube and the rod are connected by screwing the connecting nut onto the outer periphery of the other of the connecting tube and the rod.

2. The front fork according to claim 1, in, The connecting tube is embedded in the inner or outer periphery of the cover side end of the rod. One of the connecting tube and the cover-side end of the rod, which is arranged on the inner circumference side, has a flange that abuts against the end of the other. The other of the connecting tube and the cover-side end of the rod disposed on the outer periphery has a threaded portion on the outer periphery. The connecting nut is screwed onto the threaded portion, and the flange is sandwiched between the connecting tube and the other of the cover-side ends of the rod that is arranged on the outer peripheral side, thereby connecting the cover and the rod.

3. The front fork according to claim 2, in, The coupling nut has: an annular nut portion, threadedly connected to the threaded portion; An annular extension portion is connected to one axial end of the nut portion and is installed on the outer periphery of the connecting tube and the cover side end of the rod member so as to be freely movable along the axial direction; the outer periphery of at least a part of the extension portion is in a shape that can be grasped using a tool.

4. The front fork according to claim 1, in, The rod has: a cylindrical small-diameter rod member, which enters and exits the cylinder; a large-diameter rod, one end of which is connected to the end of the small-diameter rod on the opposite side of the cylinder and has an inner diameter larger than that of the small-diameter rod; The electric wire has: an inner cable housed in the small-diameter rod; an outer cable, which is accommodated in the large-diameter rod and passes through the cover to be led out from the fork body to the outside; and a connector housed in the large-diameter rod and connecting the inner cable and the outer cable; the other end of the large-diameter rod is connected to the cover via the connecting nut.

5. The front fork according to claim 1, in, The cover side end of the rod is embedded on the inner circumference of the connecting cylinder.

6. The front fork according to claim 2, in, The cover side end of the rod is embedded in the inner periphery of the connecting tube. It comprises: a suspension spring, which is arranged on the outer periphery of the rod and housed in the fork body, and urges the fork body in an extension direction; and a stopper provided on the outer periphery of the rod, that is, at a position closer to the cylinder side than the flange, and restricting the connecting nut from moving toward the cylinder side; The stopper has a mounting portion to which a tool for supporting the upper end of the suspension spring can be mounted.

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