JPH1191672A - Link type front suspension unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operation performance of a pushrod. SOLUTION: A link type front suspension 2 of the front wheel is composed of a fork pipe 20, a pushrod 21, a buffer 22, an upper link 23 and a pivot link 24. The pushrod 21 and the buffer 22 are connected to axially rotate on almost the same axis in the side view, and the upper ends of the buffer 22 and the fork pipe 20 are coupled by an upper bracket 28. Further, the backside of a top bridge 3 and a steering stem 26 that couple the fork pipe 20 at the upper and middle parts respectively are pivotally turnably installed to a head pipe 5 at the center by a stem pipe 4. The tip of the pivot link 24 is coupled with a wheel shaft 31. The length of the upper link 23 is arranged to be the same as that of the pivot link 24. The upper link 23 on the left of the vehicle body is extended forward from the coupled point with the pushrod 21 so as to couple with an installation part 34 of a front fender. Further, a fender link 25 is provided on the right of the vehicle body with an end coupled with the fork pipe 20. An almost parallelogram link is thereby formed by the upper link 23, fender link 25, front fender 32 and fork pipe 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a link type front suspension device for a motorcycle.

[0002]

2. Description of the Related Art U.S. Pat. No. 4,775,163 shows a front link type suspension for a motorcycle. The front link type suspension has a pair of front forks extending to the left and right of the front wheel, a pivot link having one end pivotally attached to the front fork and supporting the front wheel axle at the other end, and one end pivotally connected to an intermediate portion of the pivot link. , The other end of which is connected to the shock absorber.

The push rod is connected to a damper spring having an upper end fixed to the vehicle body and a lower end of the damper. Of these, the push rod is attached to the damper via a connecting arm with a different axis from the damper spring. Are coaxial but are directly connected to the spring receiver without passing through the shaft.

Further, a front fender is supported by a push rod and moves integrally.

In addition, the push rod is formed of a pair of left and right main body rods that are substantially linear, and a push rod bracket that connects these left and right main body rods and serves as a connection part with a damper or the like. It is common that they are integrated by welding or formed integrally.

[0006]

By the way, the push rod is pivotally attached to the pivot link at the lower end, and the upper end is pivotally attached to the damper via the connecting arm, and the damper spring is connected to the spring receiver. The upper end of the damper is directly connected to the top bridge, and the upper end of the damper spring is fixed to the top bridge.

Therefore, when the push rod moves up and down due to the swing of the pivot link caused by the vertical movement of the front wheel, the damper at its upper end and the connecting portion with the damper spring tend to move irregularly in the front-rear direction. The bending will be added to the rod. For this reason, the operability is deteriorated, and the weight is increased due to the need for the bending strength.
The unsprung weight increases. Therefore, a main object of the present invention is to provide a push rod excellent in operability.

Further, if the front fender is supported by the push rod and moves integrally, when the front wheel moves up and down, the stroke amount between the front fender and the front wheel does not match. It is necessary to have sufficient clearance in advance. Another object is to reduce the clearance.

Further, in the case where the body rod portion and the push rod bracket constituting the push rod are divided and welded, it is premised that the same material is used. Therefore, if iron material is used, the overall weight increases, and aluminum material is used. The use of such a light alloy increases the cost. If the whole is formed integrally, much work is required for the finishing work. Therefore, another object of the present invention is to provide a structure advantageous for manufacturing such a push rod.

[0010]

SUMMARY OF THE INVENTION To solve the above-mentioned problems, a first aspect of the present invention relates to a link type front suspension device.
A pair of left and right front forks extending vertically in the front wheel and being steerably connected to a body frame at an upper end portion, a pair of left and right push rods provided substantially in parallel with the front fork, And a link-type front suspension having a pair of left and right pivot links for rotatably supporting the axle of the front wheel while pivotally attaching the lower end of the front axle, and a shock absorber connected between the upper end of the push rod and the front fork. In a motorcycle, a push rod and a shock absorber are arranged substantially coaxially in a side view, and the two are axially attached to each other, and a pair of left and right upper links provided substantially in parallel above a pivot link and a left and right front fork. The push rods are connected to each other.

According to a second aspect, in the first aspect,
The upper link extends forward from the push rod, this extension is attached to the front fender arranged between the left and right front forks, and the upper link and pivot link are made approximately equal in length. And

[0012] In a third aspect based on the second aspect,
A fender link is provided which is substantially parallel to the upper link at different heights, has one end pivotally attached to the fender link, and the other end pivotally attached to the front fork.

[0013] In a fourth aspect based on the first aspect,
The push rod is divided into a main body rod and a push rod bracket, each of which is made of a different material, and the upper end of the main body rod is fitted and fixed to the push rod bracket.

According to a fifth aspect, in the fourth aspect,
The main body rod is connected to the push rod bracket in a threaded manner.

[0015]

According to the first aspect of the present invention, the push rod and the shock absorber are arranged substantially coaxially and axially attached to each other.
Since the upper link is provided to connect the front fork and the push rod, no bending is applied to the push rod when the front wheel is moved up and down, and the push rod operates smoothly, improving operability. In addition, by not considering bending, the push rod can simply satisfy the tensile and compressive strengths, so that the weight can be reduced, and as a result, the unsprung weight can be reduced.

According to the second aspect, the front fender is supported by using the extended portion of the upper link,
Since the upper link and the pivot link are substantially equal in length and parallel to each other, the stroke amounts of the front wheel and the front fender become substantially equal, and as a result, the clearance between the front wheel and the front fender can be set to the minimum necessary.

According to the third invention, an upper link,
The substantially parallel fender link forms a substantially quadrilateral link between the front fender and the front fork, so that the front fender can be stably supported.

According to the fourth invention, the push rod is
Since the rod body and the push rod bracket made of different materials are assembled by fitting together, different materials can be combined, and each can be made of an optimum material, and the weight can be reduced. In addition, by finishing the rod body and the push rod bracket separately, an excellent appearance and marketability can be obtained.

According to the fifth aspect of the present invention, the length of the rod body can be made variable by connecting the rod body by screwing, so that it can be commonly applied to a plurality of models having different vehicle heights. In addition, parts can be shared.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. 1 is an overall side view of a motorcycle to which the present invention is applied, FIG. 2 is an enlarged side view of a part of a link type front suspension thereof, and FIG. 3 is a front view of an upper part of a push rod.

First, in FIG. 1, a link type front suspension 2 that supports a front wheel 1 is rotatably connected to a head pipe 5 by a stem pipe 4 via a top bridge 3, and can be turned by a handle 6. I have.

The head pipe 5 includes a main pipe 8 disposed in a front-rear direction above a V-type four-cycle engine 7;
The front down pipe 9 is attached to each front end of the front down pipe 9 obliquely descending forward of the engine 7.

The rear part of the main pipe 8 is connected to a pivot plate 10 extending long in the vertical direction as a pair of left and right parts. A rear swing arm 12 having a front end supported by a pivot part 11 of the pivot plate 10 extends rearward, and a rear end. The rear wheel 13 is supported. Rear swing arm 12
Is swingable up and down around the pivot portion 11 to form a rear suspension.

A seat rail 14 extends further rearward from a rear portion of the main pipe 8, and a rear cowl 15 and a seat 16 are supported thereon. A fuel tank 17 is supported on the main pipe 8 in front of the seat 16.

The lower ends of the front down pipe 9 and the pivot plate 10 are connected by a lower frame 18 which passes under the engine 7 in the front-rear direction, and a radiator 19 is supported on the front down pipe 9.

As shown in FIG. 2, the link type front suspension 2 includes a fork pipe 20, a push rod 21 and a shock absorber 22 parallel to the fork pipe 20, an upper link 23 for connecting these intermediate parts in the vertical direction, and respective lower ends thereof. Are provided as a pair of left and right pivot links 24, respectively.

The fork pipe 20 on the right side of the vehicle body has a fender link 25 having one end connected to a vertically intermediate portion between the connection portions of the upper link 23 and the pivot link 24 and the other end connected to a front fender (described later). It has.

The left and right fork pipes 20 are connected at their upper ends by the top bridge 3 and at their intermediate portions to the steering stem 26. The top bridge 3 and the steering stem 26 are connected to the stem pipe 4 at each central portion, and the stem pipe 4 is rotatably supported in the head pipe 5.

The fork pipe 20 is a tapered pipe member whose upper portion is tapered upward from the connection with the steering stem 26 and whose lower portion is also tapered downward. It can be manufactured by a known method such as swaging the extruded pipe member into a tapered shape. The lower end of the fork pipe 20 is pivotally connected to one end of a pivot link 24 and a shaft 27.

The shock absorber 22 is composed of a known hydraulic damper having a built-in damper spring. The upper end is supported by the front of an upper bracket 28, and the lower end is connected to the upper end of the push rod 21 by a shaft 29. Is being worn.

The push rod 21 is fork pipe 20
The lower end of the pipe member extends downward substantially in parallel with the shaft member, and the lower end of the pipe member is axially attached to the intermediate portion of the pivot link 24 by the shaft 30. The other end of the pivot link 24 is connected to the axle 31 of the front wheel 1.
It is attached to the shaft.

The upper link 23 is disposed in the vicinity of a front fender 32 disposed between the left and right fork pipes 20 and the push rod 21, and has one end connected to the shaft 3.
3, the shaft is attached to the fork pipe 20, and the intermediate portion is attached to the push rod 21 by the shaft 34. The length of the upper link 23 between the shafts 33 and 34 and the length of the pivot link 24 between the shafts 27 and 31 are substantially equal.

Therefore, the fork pipe 20, push rod 21, upper link 23 and pivot link 24 constitute a substantially parallelogram link mechanism, and the front wheel 1
The push rod 21 moves substantially parallel to the fork pipe 20 in response to the vertical movement of the push rod 21.

The front ends of the left and right upper links 23
It extends further forward than the push rod 21, and its extended end is mounted on a stay 35 that projects downward from the front fender 32 with a shaft 36.

On the right side of the vehicle body, the fender link 2
5 is disposed substantially parallel to a position lower than the mounting position of the upper link 23, and one end of a shaft 38 is attached to a stay 37 that extends downward longer from a stay 35 on the right side of the vehicle body of the front fender 32, The other end is attached to the fork pipe 20 by a shaft 39.

The line connecting the shafts 36 and 37 of the stays 35 and 37 is substantially parallel to the axis of the fork pipe 20. The front fender includes the upper link 23 on the left side of the vehicle body, the fender link 25 on the right side of the vehicle body, and the stays 35 and 37. A substantially parallelogram link mechanism is constituted by the fork pipe 32 and the fork pipe 20, and the front fender 32 is moved up and down substantially in parallel in response to the vertical movement of the front wheel 1.

The caliper bracket 4 is provided around the axle 31.
0 is rotatably supported at one end and a caliper 4 is provided at the other end.
1 is supported, and can be slidably contacted with the brake disc 42 during braking to directly receive a braking force.

A stay 43 projecting rearward is formed integrally with the caliper 41, and one end of a torque link 46 is axially attached to the stay 43 by a shaft 45, and the other end is axially attached to the fork pipe 20 by a shaft 47. I have.

As shown in FIG. 3, the push rod 21 is composed of a pair of right and left rod bodies 5 made of an appropriate gold pipe such as iron.
0, a substantially U-shaped push rod bracket 51 in front view
It is composed of

The push rod bracket 51 is formed of an appropriate light alloy such as an aluminum alloy, and has a pair of left and right connecting parts 53 projecting from the left and right sides of the central bridge part 52 in an arm shape. Each connecting portion 53 has a fitting hole 54 formed in the axial direction from the lower end, and the upper end of the rod body 50 press-fitted therein is connected and fixed by a pin 55.

If a male screw is formed around the upper end of the rod body 50 and a female screw is formed in the fitting hole 54, the connection can be made by screwing. In this case, the pin 55 can be omitted. The vehicle height can be adjusted freely, and as a result, common application to a plurality of models having different vehicle heights is possible, and parts can be shared.

Above the fitting hole 54 of the connecting portion 53, a female screw hole 56 is formed from the inside of the vehicle body in a direction perpendicular to the axis, and the shaft 34 is formed by screwing a male screw portion formed at one end thereof. It is attached by inserting.

Bosses 57 are formed in the upper part of the bridge 52 at an interval on the left and right, and an insertion hole 58 that opens upward is formed in each of the bosses 57.

A connecting hole 59 is formed from the side in a direction perpendicular to the axis of the insertion hole 58. The connection holes 59 in the left and right boss portions 57 are coaxial, and the attachment legs 60 at the lower end of the shock absorber 22 are inserted into the respective connection holes 59 so that the attachment holes 61 provided in the respective attachment legs 60 coincide with the connection holes 59. The male screw portion of the shaft 29 is screwed to the female screw portion of the connection hole 59 for connection.

Next, the operation of this embodiment will be described. This link type front suspension 2 is a push rod 2
The push rod 21 and the shock absorber 22 are arranged substantially coaxially in a side view and axially attached to each other, and the push rod 21 is supported by a double link by an upper link 23 and a pivot link 24.

Therefore, since it moves up and down in parallel with the fork pipe 20 and is rotatably connected to the lower part of the shock absorber 22 and the shaft 29, it operates smoothly without being bent, so that the operability is improved. I do. In addition, by not considering bending, the push rod can simply satisfy the tensile and compressive strengths, so that the weight can be reduced, and as a result, the unsprung weight can be reduced.

Since the upper link 23, the pivot link 24 and the fender link 25 are substantially parallel and have substantially the same length, the front fender 32 strokes by substantially the same stroke as the axle 31. As a result, the clearance between the front wheel 1 and the front fender 32 can be set to a necessary minimum.

Further, the front fender 32 on the right side of the vehicle body
Is provided with a stay 37 protruding downward longer than the stay 35 to which the upper link 23 is connected, and by connecting one end of the fender link 25 to the stay 37, the upper link 23, the front fender 32, and the fork pipe 2 are connected.
0, a substantially quadrilateral link can be formed, whereby the front fender 32 can be prevented from rotating and stably supported.

Further, by providing the fender link 25 on one side (the left side in the present embodiment) rather than on both sides of the vehicle body, the number of parts and weight can be reduced, and the other parts (the torque link 46 and the like in the present embodiment) can be reduced. ) Can be easily arranged without interference. However, the arrangement of the fender links 25 on the left and right sides of the vehicle body can be arbitrarily determined according to the structure around the front wheels.

Further, since the push rod 21 is assembled by fitting the rod body 50 and the push rod bracket 51 made of different materials to each other, it is possible to combine different materials, each of which is made of an optimum material, and the weight is reduced. It becomes possible. In addition, since the rod body 50 and the push rod bracket 51 are separately finished, an excellent appearance and productability can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall side view of a motorcycle to which the present invention is applied.

FIG. 2 is a partially enlarged side view of a link type front suspension.

FIG. 3 is a front view of the upper part of the push rod.

[Explanation of symbols]

1: front wheel, 2: link type front suspension, 5:
Head pipe, 20: fork pipe, 21: push rod, 22: shock absorber, 23: upper link, 24:
Pivot link, 25: fender link, 31: axle,
35: stay, 37: stay, 50: rod body, 5
1: Push rod bracket

Claims (5)

[Claims] 1. A pair of left and right front forks extending vertically with a front wheel interposed therebetween and operably connected to a vehicle body frame at an upper end portion, and a pair of left and right push rods provided substantially in parallel with the front fork. A link-type front suspension having a pair of left and right pivot links for pivotally supporting the lower ends thereof and rotatably supporting the axles of the front wheels, and a shock absorber connected between the upper ends of the push rods and the front forks. In the equipped motorcycle,
The push rod and the shock absorber are arranged substantially coaxially in side view, and they are axially attached to each other. The left and right front forks and the push rod are connected to each other by a pair of left and right upper links provided substantially parallel above the pivot link. Link type front suspension device characterized by the following. 2. An upper link is extended forward from a push rod, and this extended portion is axially attached to a front fender disposed between left and right front forks, and the upper link and the pivot link are substantially equal in length. The link type front suspension device according to claim 1, wherein: 3. A fender link substantially parallel to the upper link at different heights, one end of which is pivotally attached to the fender link, and the other end of which is pivotally attached to the front fork. Link type front suspension device described. 4. The push rod is divided into a main body rod and a push rod bracket, each of which is made of a different material, and wherein the upper end of the main body rod is fitted and fixed to the push rod bracket. The link type front suspension device described in the above. 5. The link type front suspension device according to claim 4, wherein the main body rod is connected to the push rod bracket in a threaded manner.