JP2004276795A - Front wheel suspension for motorcycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem of a double wishbone type front wheel suspension for a motorcycle that has large parts count, large size, and difficulty in designing a vehicular body front portion. <P>SOLUTION: In the front wheel suspension for the motorcycle, one swing arm 70 , and a cushion unit 50 arranged on a rotating shaft 17 of a front fork 12 are main structure requirements. Only one swing arm is required, so that the parts count can be reduced, and the device can be simplified. The cushion unit is arranged actually coaxially with the front fork, so that the device is easily made to be compact. Therefore, in spite of adopting the swing arm, the front wheel suspension is easily to be compact, and flexibility in designing the vehicular front portion is increased, and a designing cost can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a front wheel suspension device for a motorcycle in which a swing arm is combined with a cushion unit.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a front wheel suspension device for a motorcycle in which a swing arm is combined with a cushion unit is known (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-62-198888 (FIG. 1)
[0004]
FIG. 10 is a reproduction of FIG. 1 of Patent Document 1, wherein (1) is a handle, (3) is a front wheel, (5) is an engine, (11) is a handle post, (13) is a stay, and (17). Is a knuckle, (19) is an upper swing arm, (21) is a lower swing arm, (39) is a shock absorber, and (43) is a steering link mechanism.
[0005]
Note that parentheses (parentheses) are added to distinguish them from reference numerals used in the embodiments of the invention described later. That is, in the embodiments of the invention described below, parentheses are not added to the reference numerals.
[0006]
[Problems to be solved by the invention]
The above mechanism is called a double wishbone type front wheel suspension device, and two upper and lower swing arms (19) and (21) are indispensable, and the two swing arms (19) and (21) are spaced from each other. It is necessary to place and arrange, and the device becomes large.
[0007]
Further, since the shock absorber (39) is obliquely bridged between the upper and lower two swing arms (19) and (21), the number of parts increases and the device becomes complicated.
As described above, it is not preferable to dispose a large and complicated suspension device in front of a motorcycle having a limited space, and the design of the device becomes difficult.
Therefore, there is a demand for a more compact and simpler front wheel suspension device for a motorcycle on the premise of employing a swing arm.
[0008]
[Means for Solving the Problems]
In order to respond to the above demand, claim 1 attaches a front fork supporting a front wheel to a front portion of a body frame via a front wheel suspension device so as to be vertically movable and steerable, and separated from the front wheel suspension device to a body frame. A motorcycle in which a front wheel is steered by a handle by attaching a handle and connecting a front fork to the handle via a link mechanism, and the front wheel suspension device is capable of vertically moving and steering the front fork. The steering unit consists of a cushion unit connected to the body frame, a swing arm movably mounted on the body frame or the engine mounted on the body frame, and a connecting part connecting the front end of the swing arm to the front fork. The cushion is placed on or about the axis of rotation of the front fork Characterized in that a knit.
[0009]
Since the number of swing arms is one, the number of parts can be reduced, and the apparatus can be simplified. Further, since the cushion unit is arranged substantially coaxially on the front fork, the device can be easily made compact.
Therefore, according to the first aspect, the front wheel suspension device can be made compact despite the use of the swing arm, the degree of freedom in designing the front portion of the vehicle body can be increased, and the design cost can be reduced.
[0010]
According to a second aspect of the present invention, the connecting portion is a ball joint including a ball portion provided at one of the tip of the swing arm and the front fork and a cup portion provided at the other.
[0011]
By using a ball joint as the connecting portion, the front fork can be allowed to move up and down and rotate while restricting the front fork from moving forward and backward and left and right. Moreover, since the ball joint is a small component including the ball portion and the cup portion, the size and weight of the connecting portion can be reduced.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a front structural view of a motorcycle according to the present invention. A front structure of a motorcycle 10 includes a front fork 12 supporting a front wheel 11 movably up and down and steerable via a front wheel suspension device 20. The front wheel 14 is attached to the front portion 14 of the body frame 13, separated from the front wheel suspension device 20, the handle 15 is attached to the body frame 13, and the front fork 12 is connected to the handle 15 via a link mechanism 30, so that the front wheel 11 can be steered.
[0013]
The front wheel suspension device 20 can vertically move the cushion unit 50 that connects the front fork 12 to the vehicle body frame 13 so that the front fork 12 can move up and down and can be steered, and the engine (not shown) attached to the vehicle body frame 13 or the vehicle body frame 13. And a connecting portion 80 for connecting the front end of the swing arm 70 to the front fork 12, and the cushion unit is provided on the rotation shaft 17 of the front fork that rotates with steering or substantially on the shaft. 50 are arranged.
[0014]
Details of the link mechanism 30, the cushion unit 50, the swing arm 70, and the connecting portion 80 will be sequentially described with reference to the drawings.
[0015]
FIG. 2 is an arrow view of FIG. 1 (a perspective view of the link mechanism employed in the present invention). The link mechanism 30 is called a pantograph link, and is a top that receives the handle 15 via the handle holders 31. It comprises an upper link 34, a lower link 35, and three pins 36 to 38 for connecting the plate 32 and the lower damper holder 33.
[0016]
If the handle 39 is set as the rotation axis of the handle, when the handle 15 is steered around the rotation axis 39 of the handle, the damper holder 33 can be rotated about the rotation axis 17 of the front fork via the upper and lower links 34 and 35.
[0017]
The vertical displacement of the damper holder 33 is absorbed by bending the upper and lower links 34 and 35 into a V shape. Even if the rotary shaft 17 of the front fork moves up and down and back and forth (front and rear directions of the vehicle body) with respect to the rotary shaft 39 of the handle, the movement of the handle 15 can be smoothly transmitted to the damper holder 33.
[0018]
FIG. 3 is a detailed view of a damper holder part employed in the present invention. The damper holder part 33 is an element constituting the upper part of the front fork 12, is a cylinder having a slit 41, and the inner diameter of the cylinder is the damper. Adjust to the outside diameter of 51. If the damper 51 is inserted into the damper holder 33 and the bolt 42 is tightened, the damper 51 can be easily and firmly fixed to the damper holder 33. When the bolt 42 is loosened, the damper 51 can be removed, so that the damper 51 can be easily replaced.
[0019]
FIG. 4 is a sectional view of the cushion unit employed in the present invention.
A hollow portion 43 that opens forward is provided in the front portion 14 of the vehicle body frame 13, and a portion above the hollow portion 43 is a ceiling portion 44, and a portion below the hollow portion 43 is a floor portion 45. The top plate 32 is attached by bolts 47 through the. Since the bearing 46 is interposed, the top plate 32, that is, the handle 15 can be freely rotated around the rotation shaft 39 of the handle.
[0020]
The cushion unit 50 has a damper 51 and a spring 52 as a basic structure. The damper 51 is fixed to the damper holder 33, and a lower spring receiver 53 for receiving the spring 52 is attached to the damper holder 33 or the damper 51. The upper spring receiver 54 for holding the spring 52 is attached to the damper shaft 55.
[0021]
On the other hand, a rubber mount 59 including an outer cylinder 56, rubber 57, and an inner cylinder 58 is attached below the floor 45 of the body frame 13, and a bearing 61 is fitted to the inner cylinder 58. Then, the damper shaft 55 is inserted from below into the inner race (inner ring) 62 of the bearing 61, and a nut 64 is attached to the tip (upper end) of the damper shaft 55 via the washer 63, so that the damper shaft 55 is mounted on the rubber mount 59. To the inner cylinder 58. Since the nut 64 can be inserted into the hollow portion 43 from the front, the nut 64 can be easily assembled.
[0022]
Since the bearing 61 is interposed between the rubber mount 59 and the damper shaft 55, the damper 51 can be rotated around the rotation shaft 17 of the front fork.
When the damper 51 swings back and forth (right and left in the drawing) as indicated by an arrow, the rubber 57 is deformed to allow a change in the angle.
[0023]
The rubber mount 59 can be replaced with a ball joint (see FIG. 6). For example, the bearing 61, the inner cylinder 58, the rubber 57, the outer cylinder 56, the washer 63 and the nut 64 are eliminated, and a ball portion is integrally formed at the tip of the damper shaft 55. Then, a cup portion may be provided on the floor portion 45, and a ball portion may be fitted to the cup portion.
Since the ball joint has a simple structure, compactness can be easily achieved.
[0024]
FIG. 5 is a view taken in the direction of arrows 5-5 in FIG. 1. The swing arm 70 is an A-shaped arm, and left and right legs 71, 72 are attached to brackets 73, 74 extending from the body frame by pins 75, 75. By stopping, the tip portion 76 can be swung in the front and back directions in the drawing. Further, a cup portion 81 is provided at the distal end portion 76.
[0025]
FIG. 6 is a sectional view taken along line 6-6 in FIG. 1 (however, the front fork and the front wheel are non-sectional views). The front fork 12 has an inverted Y-shape, Is provided.
The connecting portion 80 is desirably a ball joint 83 formed by fitting a ball portion 82 extending from the front fork 12 to the cup portion 81.
[0026]
The operation of the motorcycle front wheel suspension having the above configuration will be described below.
Returning to FIG. 1, the front wheel suspension device 20 allows the front fork 12 to move vertically and steerably to the cushion unit 50 that connects the front fork 12 to the body frame 13, and the front fork 12 to move vertically to the engine mounted on the body frame 13 or the body frame 13. The swing unit 70 includes a swing arm 70 attached to the front fork 12 and a connecting portion 80 connecting the front end of the swing arm 70 to the front fork 12. 50 are arranged.
[0027]
Since only one swing arm 70 is used, the number of parts can be reduced, and the apparatus can be simplified. Further, since the cushion unit 50 is disposed substantially coaxially with the front fork 12, the device 20 can be easily made compact.
Therefore, despite the use of the swing arm 70, the front wheel suspension device 20 can be made compact, the degree of freedom in designing the front part of the vehicle body can be increased, and the design cost can be reduced.
[0028]
Further, as shown in FIG. 6, the connecting portion 80 is a ball joint 83 including a ball portion 82 provided on one of the front end of the swing arm 70 and the front fork 12 and a cup portion 81 provided on the other. It is characterized by the following.
By using the ball joint 83 as the connecting portion 80, the front fork 12 can be allowed to move up and down and rotate while restricting the front fork 12 from moving back and forth and left and right. In addition, since the ball joint 83 is a small component including the ball portion 82 and the cup portion 81, the size and weight of the connecting portion 80 can be reduced.
[0029]
Next, another embodiment of the present invention will be described.
FIG. 7 is a diagram of another embodiment of FIG. 1. In FIG. 7, the same parts as those in FIG. 1 are denoted by the same reference numerals, detailed description is omitted, and points different from FIG.
That is, in this embodiment, the link mechanism 90 for transmitting the steering operation of the handle 15 to the front fork 12 by offsetting the handle rotation axis 39 to the rear by a distance δ from the front fork rotation axis 17 is used. It is characterized by being arranged along the arm 70.
[0030]
FIG. 8 is a view taken in the direction of the arrow 8-8 in FIG. 7, and the structure related to the upper link 91 will be described. The upper link 91 includes a first lever 93 fixed to a handle support shaft 92 supporting the handle 15 and a vehicle body frame. A member for connecting the second lever 94 swingably attached to the second lever 94. When the first lever 93 is rotated to a position indicated by an imaginary line by operating the handle 15, the second lever 94 is linked with the position indicated by the imaginary line. Can be rotated up to.
[0031]
FIG. 9 is a view taken in the direction of the arrow 9-9 in FIG. 7, and the configuration of the lower link 95 will be described. The lower link 95 includes a third lever 96 integrated with the second lever 94 (see FIG. 8), This is a member for connecting a bracket 97 attached to, for example, the right leg of the fork 12, and when the third lever 96 rotates to the position of the imaginary line, the front fork 12 can be rotated to the position of the imaginary line.
Therefore, the steering operation of the steering wheel can be transmitted to the front fork 12, and predetermined steering can be performed.
[0032]
By the way, in FIG. 9, the tip of the swing arm 70 moves in the front and back direction of the drawing. This movement can be absorbed by providing a ball joint 100 including a ball part 98 and a cup part 99 at one end (preferably both ends) of the lower link 95. Reference numeral 101 denotes a recess provided on the upper surface of the swing arm 70. By providing the recess 101, interference between the swing arm 70 and the lower link 95 can be avoided.
[0033]
The angle adjustment between the handle 15 (see FIG. 8) and the front fork 12 can be arbitrarily performed by a length adjustment mechanism 105 including a nut portion 102, a bolt portion 103, and a lock nut 104.
[0034]
Returning to FIG. 7, as a result of the upper link 91 being along the body frame 13 and the lower link 95 being along the swing arm 70, the front portion of the motorcycle 10 can be cleared.
Further, the position of the handle 15 can be moved back and forth (for example, by δ) to the vehicle body, and the degree of freedom in designing the front part of the vehicle body can be remarkably improved.
[0035]
【The invention's effect】
The present invention has the following effects by the above configuration.
Claim 1 has a main configuration requirement of one swing arm and a cushion unit arranged on the rotation axis of the front fork. Since one swing arm is used, the number of parts can be reduced, The apparatus can be simplified. Further, since the cushion unit is arranged substantially coaxially on the front fork, the device can be easily made compact.
Therefore, according to the first aspect, the front wheel suspension device can be made compact despite the use of the swing arm, the degree of freedom in designing the front portion of the vehicle body can be increased, and the design cost can be reduced.
[0036]
According to a second aspect of the present invention, the connecting portion is a ball joint including a ball portion provided at one of the tip of the swing arm and the front fork and a cup portion provided at the other, and the connecting portion is formed as a ball joint. By doing so, it is possible to allow the front fork to move up and down and rotate while restricting the front fork from moving forward and backward and left and right. Moreover, since the ball joint is a small component including the ball portion and the cup portion, the size and weight of the connecting portion can be reduced.
[Brief description of the drawings]
1 is a front structural view of a motorcycle according to the present invention; FIG. 2 is a perspective view of a link mechanism employed in the present invention; FIG. 3 is a detailed view of a damper holder employed in the present invention; FIG. FIG. 5 is a sectional view taken along line 5-5 in FIG. 1 FIG. 6 is a sectional view taken along line 6-6 in FIG. 1 (however, front forks and front wheels are not sectioned)
FIG. 7 is a view of another embodiment of FIG. 1 FIG. 8 is a view taken in the direction of arrows 8-8 in FIG. 7 FIG. 9 is a view taken in the direction of arrows 9-9 of FIG. 7 FIG. Figure [Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 11 ... Front wheel, 12 ... Front fork, 13 ... Body frame, 14 ... Front part of body frame, 15 ... Handle, 17 ... Rotation axis of front fork, 20 ... Front wheel suspension device, 30, 90 ... Link Mechanism: 39: handle rotation axis, 50: cushion unit, 51: damper, 52: spring, 59: rubber mount, 70: swing arm, 80: coupling part, 81: cup part, 82: ball part, 83: ball Joint.

Claims (2)

A front fork supporting the front wheels is mounted on the front of the body frame via a front wheel suspension so as to be vertically movable and steerable, and a handle is attached to the body frame separately from the front wheel suspension, and a link mechanism is connected to the handle via a link mechanism. By connecting the front fork, the front wheel can be steered by the steering wheel,
The front wheel suspension device includes a cushion unit that connects the front fork to the body frame so as to be vertically movable and steerable, a swing arm attached to the body frame or an engine attached to the body frame so as to be vertically movable, and a front end of the swing arm. A connecting portion connected to the front fork,
A front wheel suspension device for a motorcycle, wherein the cushion unit is arranged on or substantially on the rotation axis of a front fork that rotates with steering. The front wheel suspension for a motorcycle according to claim 1, wherein the connecting portion is a ball joint including a ball portion provided at one of a tip of a swing arm and a front fork and a cup portion provided at the other. apparatus.

Images