JPH05112276A - Front wheel suspension device of motorcycle and motortricycle - Google Patents

Abstract

PURPOSE:To form a car body in a slim state and to improve cooling ability of an engine by arranging a lower arm above a front wheel together with an upper arm and forming no member protruding to the side of the front wheel. CONSTITUTION:Right and left plates 7 are arranged in a frontward protrusion state to the upper part of a down pipe 4 being a constituting element for a car body frame 1. Upper and lower arms 38 and 39, of which a front wheel suspension device is composed, are pivotally supported to the plates 7 by means of support axles 43 and 44 together with a knuckle arm 37. Thereby, a member protruding to the side of a front wheel 35 is not formed. It is achieved that a car body is formed in a slim state. Further, a steering shaft 106 is arranged to the upper part of the knuckle arm 37 and the steering shaft 106 is rotatably supported by means of a pipe member 109. The pipe member 109 is pivotally mounted on the front end part of the upper arm 38 through a pivot shaft 111 divided into sections on right and left sided, whereby a mounting space in a vertical direction may be reduced and slimness of the car body is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quadrilateral link type front wheel suspension system for motorcycles.

[0002]

2. Description of the Related Art In a motorcycle, a quadrilateral link is formed by pivotally connecting a vehicle body and a front wheel support member with an upper arm and a lower arm which are vertically paired with each other, and the upper arm is arranged above the front wheel. A suspension device in which a front wheel is disposed laterally is disclosed in Japanese Patent Laid-Open No. 64-5258.
It is known from Japanese Patent No.

[0003]

However, since there is a lower arm on the side of the front wheel and the lower arm is curved to the side in order to secure steering of the front wheel, a large bending to the side is required. The shaped lower arm is inconvenient for slimming the vehicle body and smoothing the inflow of traveling wind to the engine side.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a front wheel suspension system for a motorcycle having a quadrilateral link type front wheel suspension system, which can slim the vehicle body and improve the cooling performance of the engine.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention relates to an automatic two-piece structure in which a vehicle body and a front wheel support member are pivotally connected to each other by an upper arm and a lower arm which are paired vertically.
In a front wheel suspension system for a three-wheeled vehicle, the upper arm and the lower arm are both arranged above the front wheel. More specifically, a steered shaft is provided above the front wheel support member, and a pipe member that rotatably supports the steered shaft via upper and lower bearings is provided, and between the upper and lower bearings of the pipe member. The front end portion of the upper arm or the lower arm is pivotally attached via a pivot shaft divided into right and left.

[0006]

By arranging the lower arm as well as the upper arm above the front wheel, there is no member protruding laterally of the front wheel, so that the body can be made slim and the flow of cooling air to the engine can be smoothed.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1 showing an example of a motorcycle to which the present invention is applied, 1 is a vehicle body frame, 11 is an engine, 21 is a handlebar, 22 is a meter unit, 23 is a left / right two-light headlight, 24 is a fuel tank, and 25 is Carburetor, 2
6 is an air cleaner, 27 is an exhaust pipe, 28 is a muffler, 29
Is a radiator, 31 is a seat, 32 is an upper cowl,
33 is an under cowl, 34 is a rear cowl, 35 is a front wheel, 36 is a front fender, 37 is a knuckle arm that is a front wheel supporting member, 38 and 39 are upper arms and lower arms that form parallel links, 41 is a rear wheel, and 42 is a swing. It is an arm.

The body frame 1 is, as shown in FIG.
A front wheel suspension together with a knuckle arm 37 is mounted on the left and right plates 7 which are formed by the head pipe 2, the main pipe 3, the left and right down pipes 4, the left and right seat pipes 5, the sub pipes 6, and the like. An upper arm 38 and a lower arm 39 that constitute the device are pivotally supported by supporting shafts 43 and 44, respectively, and left and right plates 8 projecting rearward from the lower portion of the down pipe 4 are provided.
A swing arm 42 that constitutes a rear wheel suspension device is pivotally supported by a support shaft 45. The engine 11 has a cylinder portion 13 installed upright on a crankcase 12, and the cylinder portion 13
A carburetor 25 and an air cleaner 26 are provided in the rear of the cylinder section, and an exhaust pipe 27 and a muffler 28 are provided in the rear section of the cylinder section 13. A radiator 29 is arranged in the front of the cylinder section 13 in the upper cowl 32. A cooling air introduction port 46 to the cylinder portion 13 and the radiator 29 is formed on the lower front surface of the. Next, the drive device will be described.

Inside the crankcase 12 of the engine 11, as shown in FIG. 3, a crankshaft 14 and a main shaft 15 are provided.
The counter shaft 16 is housed, and the clutch 1
7 and the reduction gear train 18 are housed, and a hydraulic pump 51, which is rotationally driven by the counter shaft 16, is provided on the side surface of the crankcase 12. This hydraulic pump 51
Is a swash plate type, that is, a plurality of pistons 53 ... Are incorporated in a cylinder block 52 integrated with the counter shaft 16, and each head portion of the pistons 53 ... Is provided. The swash plate 54 has a variable tilt angle by an actuator 55, and the operation of the actuator 55 is controlled by a control unit 50. The control unit 50 is disposed below the seat 31 as shown in FIG. Has been done.

A swash plate type hydraulic motor 61 is incorporated in the hub of the front wheel 35. That is, the cylinder block 63 integrally provided in the hub of the front wheel 35 is rotatably supported on the support shaft 62 which is cantilevered at the lower end of the knuckle arm 37 at the right end, and a plurality of cylinder blocks 63 are supported in the cylinder block 63. , And the fixed swash plate 65 with which the heads of the pistons 64 are brought into pressure contact is provided. The suction oil passage 66 of the hydraulic motor 61 is connected to the discharge oil passage 56 of the hydraulic pump 51 via a supply oil passage 68, and the hydraulic motor 6
The discharge oil passage 67 of No. 1 is the intake oil passage 5 of the hydraulic pump 51.
7 through a return oil passage 69.

Further, a swash plate type hydraulic motor 71 is also incorporated in the hub of the rear wheel 41. That is, the cylinder block 73 integrally provided in the hub of the rear wheel 41 is rotatably supported on the support shaft 72, which is cantilevered at the left end portion at the rear end portion of the swing arm 42. Is assembled with a plurality of pistons 74, and a fixed swash plate 75 with which the heads of the pistons 74 are brought into pressure contact is provided. Similarly, the intake oil passage 76 of the hydraulic motor 71 is also connected to the discharge oil passage 56 of the hydraulic pump 51 via the supply oil passage 78, and the discharge oil passage 77 of the hydraulic motor 71 is also connected to the hydraulic pump 5.
It is connected to the first intake oil passage 57 through a return oil passage 79.

A variable orifice device 81 is provided in the discharge oil passage 56 from the hydraulic pump 51 which branches into the front and rear supply oil passages 68 and 78, and the front and rear return oil passages 69 and 79 join the hydraulic pump 51. Intake oil passage 57
Also, the same variable orifice device 81 is provided. That is, inside the variable orifice device 81, as shown in FIG. 4, pistons 82 that respectively advance into the discharge oil passage 56 and the intake oil passage 57, a spring 83 that biases the piston 82 toward the backward side, and a piston 82 has an internal lever 84 and the like, one end of which abuts, and the portion where the piston 82 advances is a variable orifice 85 that narrows the oil passage. The variable orifice device 81 on the discharge oil passage 56 side and the variable orifice device 81 on the intake oil passage 57 side.
As shown in FIG. 3, each has an outer lever 86 coaxial with the inner lever 84.
Is connected to the connector 88 via cables 87, 87,
A control cable 89 is connected to the connector 88.

The control cable 89 is connected to a brake lever 92 provided on the throttle grip 91 side of the handle 21. Here, 93 is a throttle valve, 94 is a throttle opening detector, and 95 is an engine speed detector.
Also, the detection signals of the engine speed detector 95 are input to the control unit 50. Then, the control unit 50 uses the swash plate 54 for gear shift operation of the hydraulic pump 51 based on the throttle opening and the engine speed.
Of the variable orifice device 81 on the discharge oil passage 56 side of the hydraulic pump 51 while controlling the automatic speed change operation by changing the inclination angle of the actuator 55 by the operation of the actuator 55.
In the above, the variable orifices having the same structure provided on the front and rear supply oil passages 68 and 78 are respectively controlled to control the front wheel 35.
And the driving force distribution ratio of the rear wheels 41 is optimally controlled.

On the other hand, the front wheel steering system has the configuration shown in FIG. That is, the upper and lower bearings 10 are provided in the head pipe 2.
The handle 21 is fixed to the upper end of a steering shaft 102 that is rotatably supported via 1, 101, and a drive pulley 103 is fixed to the upper part of the steering shaft 102.
Left and right cables 104 paired with this drive pulley 103
Is fixed at one end thereof, and 105 is a cable outer. As shown in FIGS. 13 and 14, a steering shaft 106 is fixedly installed on the upper end portion of the knuckle arm 37 that cantilevers the front wheel 35 from the right side of the vehicle body. The driven pulley 107 is fixed. The other end of the cable 104 forming a pair on the left and right is fixed to the driven pulley 107, and the steering shaft 10
6 is a pipe member 1 via upper and lower bearings 108, 108.
It is rotatably supported by 09.

Further, the pipe member 109 is provided with the upper arm 38 via a pivot shaft 111 divided into left and right.
Is pivotally supported at the front end of the. That is, FIG. 9 and FIG.
As shown in detail in FIG. 1, the left and right pivot shafts 111, 11 are provided between the upper and lower bearings 108, 108 of the pipe member 109.
1 is assembled via bearings 112, 112, and the heads of the pivot shafts 111, 111 are assembled to the front end portions of the left and right side pieces 38b, 38b of the upper wall 38a of the upper arm 38. Reference numeral 113 is a lock nut, and 114 is a cap. A protruding rod 115 extending downward and rearward is integrally formed in the lower portion of the pipe member 109. The left and right bifurcated distal ends 116 of the protruding rod 115 are provided with a bearing 117 at the front end of the lower arm 39. Support shaft 11 installed through
8 is assembled.

The supply oil passage 68 and the return oil passage 69 between the hydraulic pump 51 and the hydraulic motor 61 in the hub of the front wheels 35 are constructed as shown in FIGS. 2 and 3 and FIGS. 6 to 8. First, as shown in FIG. 3, the intake oil passage 66 and the discharge oil passage 67 of the hydraulic motor 61 are formed in the lower portion of the knuckle arm 37, and the supply oil passage 68 and the return oil passage 69 are as shown in FIG. , The support shaft 4 of the upper arm 38
In the three parts, the hose 68a, 69 divided into front and rear
It has a and hoses 68b and 69b. Hoses 68a, 6
9a is disposed through the upper arm 38. Then, as shown in FIG. 6, the left and right plates 7, 7 are
A pipe 1 for inserting and supporting the support shaft 43 of the upper arm 38.
21 is horizontally fixed, and the supply-side and return-side oil passages are formed symmetrically in the upper arm 38 from the pipe 121 through the support shaft 43.

That is, the support shaft 43 is composed of the left and right plates 7, 7
The bearings 122, 12 are installed in the pipe 121 fixed horizontally across the space.
2 and the collar 123, and the rear wall portion 38 of the upper arm 38 is attached to the left and right ends of the support shaft 43.
c Left and right boss portions 38d, 38d are supported via bearings 124, 124, respectively. 125 is bearing 124,12
It is a color between four. An oil supply passage 68c connected to the hose 68a is formed in the pipe 121, and the oil supply passage 68c is continuously connected to the collar 123.
d, the oil supply passage 68e for the support shaft 43, the oil supply passage 68f for the collar 125, and one boss portion 38 of the upper arm 38.
A supply oil passage 68g is formed in each of d, and the hose 68a is connected to an opening to the front surface of the rear wall portion 38c of the supply oil passage 68g. 126 is a hose connection fitting,
127 is a blind plug at the open end of the oil supply passage 68e of the support shaft 43. On the contrary, the other boss portion 38d of the upper arm 38 is provided with a return oil passage 69c which is open to the front surface of the rear wall portion 38c and is connected to the hose 69a, and which is continuous with the return oil passage 69c. Return oil passage 69d,
A return oil passage 69e is formed in the support shaft 43, a return oil passage 69f is formed in the collar 123, and a return oil passage 69g is formed in the pipe 121. The hose 69a is formed in the return oil passage 69g.
Are connected. Reference numeral 128 is a hose connection fitting, and 129 is a blind plug at the open end of the return oil passage 69e of the support shaft 43.

As shown in FIGS. 7 and 8, an under cover 131 is attached to the lower surface open portion of the upper arm 38. The supply oil passage 78 and the return oil passage 79 between the hydraulic pump 51 and the hydraulic motor 71 in the hub of the rear wheel 41 are configured as shown in FIGS. 2 and 3. That is, as shown in FIG. 3, the intake oil passage 76 and the discharge oil passage 77 of the hydraulic motor 71 are formed in the rear part of the swing arm 42, and the supply oil passage 78 and the return oil passage 79 are as shown in FIG. , A hose arranged through the swing arm 42.

As shown in FIG. 3, a rotary damper 132 is provided around one of the support shafts 45 of the swing arm 42. In addition, the upper arm 38 on the front wheel 35 side
A similar rotary damper 133 is also provided around the support shaft 43 (see FIGS. 5, 6, 7 and 13). As shown in FIG. 11, a rotary damper 134 for the swing arm 42 is arranged on the outer periphery of the hydraulic pump 51 on the engine 11 side, and the rotary damper 134 and the engine 11 are attached to the vehicle body frame 1'and The swing arm 42 may be supported via B.

According to the motorcycle described above, the control unit 50 changes the inclination angle of the swash plate 54 for speed change operation of the hydraulic pump 51 by the operation of the actuator 55 based on the throttle opening and the engine speed.
The discharge hydraulic pressure of the swash plate hydraulic pump 51 driven by 1 is supplied to the swash plate hydraulic motor 61 in the hub of the front wheels 35 via the supply oil passage 68, and also to the rear wheel 41 hub via the supply oil passage 78. It is supplied to the swash plate type hydraulic motor 71 inside. In this way, the front wheels 35 and the rear wheels 41 are both driven by the hydraulic pressure, and the gear shifting operation is performed automatically.

The braking operation is performed by the variable orifice device 81 provided on the discharge oil passage 56 side of the hydraulic pump 51 and the variable orifice device 81 also provided on the suction oil passage 57 side of the hydraulic pump 51. That is, when the brake lever 92 is grasped, the control cable 8
9, connector 88, cables 87, 87 and external lever 8
The internal levers 84 and 84 simultaneously swing via 6 and 86, and the pistons 82 and 82 advance synchronously into the discharge oil passage 56 and the intake oil passage 57, whereby the oil passages of the variable orifices 85 and 85 are moved. Are squeezed at the same time. In this way, the variable orifice 8 is provided in both the oil passages on the supply side and the return side.
Since the oil passage is simultaneously throttled by 5,85, the front wheel 35
The oil flow rate supplied to the swash plate type hydraulic motor 61 in the hub and the rear wheel 41 in the hub decreases, and the rotations of the front and rear hydraulic motors 61, 71 are simultaneously braked. 35 and the rear wheel 41 are braked.

The front and rear supply oil passages 6 in the variable orifice device 81 on the side of the discharge oil passage 56 of the hydraulic pump 51.
The control unit 50 controls each of the variable orifices provided on the 8 and 78 sides based on the throttle opening and the engine speed, so that the drive force distribution ratio between the front wheels 35 and the rear wheels 41 can be optimally obtained. A pipe member 109 that rotatably supports a steering shaft 106 that is fixed to the upper end of a knuckle arm 37 that supports the front wheels 35 from the right side of the vehicle body is rotatably supported by an upper arm 38 and a lower arm 39. Since the lower end of the front arm 35 is pivotally connected and the lower arm 39 is arranged above the front wheel 35 together with the upper arm 38, the plate-shaped knuckle arm 37 is located only on one side of the front wheel 35 as shown in FIG. It is only. Therefore, since it is not necessary to extend the lower arm to the side of the front wheel 35 as in the conventional case, the vehicle body can be made slim and, as shown in FIG.
The cylinder portion 13 of the engine 11 and the radiator 2 in front of it
It is possible to improve the cooling efficiency by minimizing the obstacles of the traveling wind flowing from the front to the 9th part.

Further, by providing a rotary damper 133 around the support shaft 43 of the upper arm 38, the engine 1
By arranging the damper to the upper front of 1,
This contributes to slimming the vehicle body and improving engine cooling. Further, with respect to the pipe member 109 that rotatably supports the steered shaft 106 at the upper end of the knuckle arm 37, the upper arm 38 is interposed between the upper and lower bearings 108, 108 via the left and right pivot shafts 111, 111.
Since the steering shaft 106 and the pivot shaft 111 are made to intersect by pivotally connecting the side end portions 38b and 38b of the pipe member 1 supporting the steering shaft 106 to each other.
The structure around the pipe member 109 can be made compact without the need for a structure to pass the pivot shaft above and below or in the front and rear of 09.

FIG. 15 shows an example in which a disc brake is used for the front wheels 35. In this case, the wheel center line C.I. A disc rotor 135 and a brake caliper 136 are arranged on the side opposite to the knuckle arm 37 with respect to L.
Ensure the steering balance. Next, FIGS. 16 to 19 showing an example of the case where the retractable dampers are used in the front and rear will be described. That is, as shown in FIG. 16, the front end portion of the telescopic damper 137 is connected to the rear end portion of the upper arm 38, and the telescopic damper 138 is also connected to the front end portion of the swing arm 42, so that the front and rear telescopic dampers are connected. Thirteen
7, 138 are connected by a connecting shaft 139.

Specifically, as shown in FIGS. 17 and 18,
In the recess 141 at the rear end of the upper arm 38, the pipe-shaped front end 137 a of the telescopic damper 137 is attached to the bolt 1.
43 and a nut 142. 144 is a hole for assembling a bolt and nut provided in the side piece portion 38b of the upper arm 38. Although not shown, the swing arm 42
The connection structure between the front end and the rear end of the telescopic damper 138 is substantially the same. As shown in FIG. 19, the left and right bifurcated rear end portions 1 of the telescopic damper 137 at the front are provided between the stays 9 and 9 projecting rearward at the upper portions of the left and right down pipes 4, 4.
37b and the pipe-shaped front end portion 138a of the retractable damper 138 at the rear are pivotally connected by a connecting shaft 139.
145 is a bolt for fixing the end of the connecting shaft 139 to the stay 9.

Thus, the telescopic damper 1 for the front wheel 35
37 and a telescopic damper 138 for the rear wheel 41 are arranged substantially in the same axis, and the spaces between them are opposed to each other and supported between the down pipes 4 and 4 of the vehicle body frame 1 via a connecting shaft 139. With this, the rigidity that the body frame 1 bears can be reduced. Incidentally, the vehicle body structure, the drive device, the suspension device, the steering device, and other specific detailed structures are not limited to the structures of the embodiments, and can be changed appropriately. For example, the front end of the lower arm may be pivotally mounted between the upper and lower bearings of the pipe member via a pivot shaft that is divided into left and right. Although the motorcycle has been described above as an example, it may be applied to a three-wheeled vehicle.

[0027]

As described above, according to the front wheel suspension system for a motorcycle according to the first aspect of the present invention, the lower arm and the lower arm are arranged above the front wheel, so that the member protruding laterally of the front wheel can be eliminated. Therefore, it is possible to slim the vehicle body and improve the cooling performance of the engine. According to the second invention, since the arm support shaft is provided on the side surface of the pipe having the steered shaft, the vertical mounting space is small, the vertical space can be effectively utilized, and the vehicle body can be made slim. Is improved.

[Brief description of drawings]

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

FIG. 2 is a side view showing hydraulic piping.

FIG. 3 is a configuration diagram of a hydraulic drive device.

FIG. 4 is a sectional view of the variable orifice portion.

FIG. 5 is a cutaway side view showing a front wheel steering device.

6 is a cross-sectional view taken along the line AA of FIG.

7 is a cross-sectional view taken along the line BB of FIG.

FIG. 8 is a sectional view taken along the line CC in FIG.

9 is a sectional view taken along the line DD of FIG.

10 is a cross-sectional view taken along the line EE of FIG.

FIG. 11 is a side view showing an example in which a rotary damper is provided on the outer circumference of the hydraulic pump.

FIG. 12 is a transverse plan view of the same.

FIG. 13 is a schematic perspective view of a front wheel suspension device according to the present invention.

FIG. 14 is a front view of the same.

FIG. 15 is a rear view showing an example in which a disc brake is provided.

FIG. 16 is a schematic side view of a motorcycle showing an example in which a telescopic damper is adopted in the front and rear.

FIG. 17 is an exploded perspective view of an upper arm and a telescopic damper.

FIG. 18 is a sectional view of the connecting portion.

FIG. 19 is a plan view showing a connecting portion of front and rear telescopic dampers.

[Explanation of symbols]

1 ... Body frame, 35 ... Front wheel, 37 ... Front wheel support member,
38 ... upper arm, 39 ... lower arm, 106 ...
Steering shaft, 108 ... Bearing, 109 ... Pipe member, 111 ...
Pivot axis.

Claims (2)

[Claims] 1. A front wheel suspension system for a motorcycle, comprising a vehicle body and a front wheel support member pivotally connected to each other by an upper arm and a lower arm forming a pair of upper and lower sides, wherein the upper arm and the lower arm are both arranged above the front wheel. Front wheel suspension system for motorcycles, which is characterized by that. 2. A steered shaft is provided above the front wheel support member, a pipe member is provided for rotatably supporting the steered shaft via upper and lower bearings, and between the upper and lower bearings of the pipe member, A front wheel suspension system for a motorcycle, wherein a front end portion of the upper arm or the lower arm is pivotally mounted via a pivot shaft divided into right and left.