JPH02293290A - Steering system for vehicle - Google Patents

Abstract

PURPOSE:To secure a sufficient steering angle without interfering with a fuel tank and a fairing by constituting linkage with a pair of rocking links, a pair of tension links and a pair of connecting rods. CONSTITUTION:When symmetrical handles 9L, 9R are rotated, driving is carried out by a pair of connecting rods 20L, 20R connected to rocking links 13L, 13R, rotating a top bridge 5 around a steering column 4, thus a front wheel is steered. At this time, with rotation of handle bases 10L, 10R, the rocking links 13L, 13R connected to a handle bracket 8 by tension links 17L, 17R are relatively rotated to these handle bases 10L, 10R. With this rotation, a relative positional relationship between the handle bases 10L, 10R and the connecting rods 20L, 20R varies according to each steering angle of the handles 9L, 9R, and if this steering angle is small, the steering angle is transmitted to the front wheel at the ratio of 1 : 1, and it is enlarged in proportion as going to larger, thus it is transmitted to the front wheel.

Description

[Detailed Description of the Invention] A. Object of the Invention (1) Industrial Application Field The present invention relates to a steering device mounted on a motorcycle, etc., and more particularly to a steering device in which a front fork for suspending a front wheel and a handle are separated and the two are interlocked and connected by a link. .

(2) Conventional technology Conventionally, in a steering device for a motorcycle, etc., a steering stem is rotatably supported on a head pipe provided at the front of a vehicle body frame, and a front fork connected to this steering stem, and a front A fork is known in which the fork is connected to a handle pivotally supported by a handle bracket on the upper part of the fork via a link mechanism (see, for example, Japanese Utility Model Application No. 61-3509).

(3) Problems to be Solved by the Invention However, when the steering angle of the steering wheel is increased in order to ensure a large steering angle of the front wheels in the above-mentioned conventional steering device, the steering wheel interferes with the fuel tank and fairing during full steering. This results in restrictions on the degree of freedom in designing the fuel tank and fairing. If the length of the handle is shortened to avoid this, a new problem arises: the rudder torque decreases and the handle becomes heavier. The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a steering device that can ensure a sufficient steering angle and steering torque without interfering with a fuel tank or a fairing.

B. Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a front fork that is pivotally supported on a frame via a steering stem, and a front wheel that is pivotally supported on the lower part of the front fork. With,
In a vehicle steering device in which left and right handles consisting of a grip part and a handle base are pivotally supported on a handle bracket fixed to the frame, and these handles and a front fork are connected by a link mechanism, the left and right handle bases are pivoted. are each independently pivoted to the steering wheel bracket via the steering stem, and the steering wheel pivot is positioned on the rotation axis of the steering stem;
The link mechanism includes a pair of swing links whose intermediate portions are pivoted to the left and right handle bases, a pair of tension links that connect the inner ends of these swing links to the handle bracket, and an outer side of the swing links. The first feature is that it consists of a pair of connecting rods that connect the end and the front fork. Further, the present invention provides a front fork that is pivotally supported on the frame via a steering stem, a front wheel that is pivotally supported on the lower part of the front fork, and a left and right grip that includes a grip portion and a handle base that is attached to a handle bracket that is fixed to the frame. In a vehicle steering device in which the handlebars are pivotably supported, and these handlebars and a front fork are connected by a link mechanism, the left and right handlebar bases are each independently pivoted to a handlebar bracket via a handlebar pivot, and the handlebar pivot are provided on the left and right sides of the handle stem, and the left and right handle bases pivoted to each handle pivot are crossed in front of the handle stem,
A second feature is that the link mechanism is configured by a pair of connecting rods that are connected to the left and right grip portions on opposite sides of the handle stem, and that connect the front fork and the front position of the handle pivot at each handle base. shall be.

(2) Effect According to the first feature of the present invention, when the left and right handles, which are independently pivoted on handle pivots provided on the handle bracket, are rotated in one direction, the swinging motions that are pivoted on the left and right handle bases are rotated. Driven by a pair of connecting rods connected to the outer ends of the links, the top bridge rotates around the steering stem, and the front wheels supported by the top bridge via the front forks are steered. At this time, as each handle base rotates, the swing link whose inner end is connected to the handle bracket by a tension link rotates relative to the handle base. This results in
The relative positional relationship between the handle base and the connecting rod changes depending on the steering angle, and when the steering angle is small, that steering angle is transmitted to the front wheels on a nearly one-to-one basis, increasing the steering angle. As the turning angle increases, the turning angle is expanded and transmitted to the front wheels. Therefore, the turning angle of the front wheels can be secured to be larger than the final turning angle of the steering wheel. According to the second feature of the present invention, when the left and right handles, which are independently pivoted on a pair of left and right handle pivots provided on the handle plate, are rotated in one direction, the handle pivots at the bases of the left and right handles are rotated. Driven by a pair of connecting rods connected to the front, the top bridge rotates around the steering stem, and the front wheels, which are supported by the top bridge via the front fork, are steered. At this time, the position of the handle pivot, which supports each handle base, is on the opposite side of the grip from the steering stem, so it is possible to secure a large distance between the handle pivot and the grip. It becomes possible to obtain steering torque. Therefore, even if the steering angle is reduced to avoid interference with the fuel tank or fairing, the steering angle can be expanded and transmitted to the front wheels.

(3) Examples Embodiments of the present invention will be described below based on the drawings.

1 to 4 show a steering device for a vehicle according to an embodiment of the present invention, FIG. 1 is a schematic side view of a motorcycle equipped with the device, and FIG. 2 is a perspective view of the steering device. , FIG. 3 is a plan view thereof, and FIG. 4 is a graph showing the relationship between the steering wheel turning angle and the front wheel turning angle.

As shown in FIG. 1, the motorcycle M has a head pipe 1,
It is equipped with a frame F composed of a main pipe 2, a down tube 3, etc., and on this frame F are mounted an engine E1, a fuel tank T, a sea }S, and a fairing C.
is installed. A top bridge 5 and an under bridge 6 are fixed to both upper and lower ends of the steering stem 4, which is rotatably supported within the head viper 1, and extends downward by connecting the left and right front portions of these bridges 5.6. A front wheel Wf is supported at the lower ends of the pair of front forks 7. Then, the inverted L with the lower end fixed to the frame F
Left and right handles 9L and 9R are pivotally supported on the upper surface of the letter-shaped handle bracket 8.
L, 9R and the top bridge 5 are connected by a link mechanism L.

As shown in detail in FIGS. 2 and 3, the left and right handles 9L, 9R have handle bases 10L, 10R and a grip portion 11L. 11R, and left and right handle bases 10L. The IOR is pivotally supported on the lower and upper surfaces of the handle bracket 8 on the rotational axis of the steering stem 4 by handle pivots 12 independently on the left and right sides. A pivot 14 is located at the center of the swing links 13L and 13R in the longitudinal direction of the left and right handle bases 10L and IOH.
These swing links 13L, 13
A pair of tensigon links 17L, 17 are connected to the inner end of R and the handle bracket 8 via pins 15 and l6.
Both ends of R are pivoted. The position of the pin 16 that pivotally supports the tension links 17L and 17R on the handle bracket 8 is set slightly forward of the position of the handle pivot 12 in the direction of movement of the vehicle body.

On the other hand, a pair of connecting rods 20L are connected to the outer ends of the swing links 13L, 13R and the front center of the top bridge 5 via a pin 18 and a pivot l9. Both ends of 2OR are pivoted. A turnbuckle 2l with reverse threads formed at both ends is attached to the intermediate portion of the connecting rods 20L and 20R, and by rotating this turnbuckle 21, the connecting rod 20L. The length of 20R can be finely adjusted.

In this way, there are tension links l7L, 17R between the left and right handle bases 10L, 10R and the tongue ridge 5.
, swing link 1 3 L, . 1 3 R, connecting rod 20L, 201'? The handles 9L, 9R have grip portions 11L. By transmitting the scraping action of 11R to the top bridge 5, the front wheel W supported on the front fork 7
f is designed to rotate around the steering stem 4. Next, the operation of this embodiment will be explained.

As shown in FIG. 3, when the left and right handlebars 9L, 9R are at the neutral position PO, the link mechanism L is positioned symmetrically with respect to the center line of the vehicle body. From this state, handle 9
When L and 9R are steered to the right to position P1, the swing links 13L and 13R provided at the handle base 10L and IOR
The position of the pivot 14 moves. Then, handle base 1
Handle pivot point 12, which is the center of rotation of 0L10R, and pin 1, which is the center of rotation of tension links 17L and 17R.
Since position 6 is undefeated, left and right swing links 1
3L and 13R both rotate around the axis l4. That is, a compressive force acts on the left tension link 17L, causing the swing link 13L to rotate slightly in the direction of arrow A, and a tensile force acts on the right tension link 17R, causing the swing link 13R to rotate in the direction of arrow B. Rotate widely in the direction. As a result, the position b of the pin 18 of the right connecting rod 2OR is shifted from the position a of the pin 18 of the left connecting rod 20L to the corresponding handle base 10L, IOR.
The connecting ronds 20L, 20R are displaced rearward in the traveling direction of the vehicle body, and the positions of the rejection shafts 19 of the connecting ronds 20L, 20R are displaced by an angle α to the right of the perpendicular bisector I1 of the left and right handle bases 10L, 10R. This indicates that the rotation angle of the top bridge 5 that rotates around the handle stem 4 together with the frame axis I9, that is, the front wheel turning angle θW is larger than the handle turning angle θh.

To explain this based on Fig. 4, the steering wheel turning angle θ
When h is small, the front wheel turning angle θW also increases in an approximately 1:1 proportional relationship with this θh, but as the steering wheel turning angle θh increases, the increase ratio of the front wheel turning angle θW increases,
In the end, the value of the steering wheel turning angle θh to obtain the maximum front wheel turning angle of 35'' is only 31°. Therefore, as shown in Fig. 3, the steering wheel turning angle 9 when the front wheel Wf is fully steered is 31°.・The positions P1 of L and 9R are both inside compared to the corresponding position PI' of the conventional handle, and it is possible to provide a margin of space between the fuel tank T and the fairing C. Fig. 5 and FIG. 6 shows another embodiment of the present invention, in which FIG. 5 is a perspective view of the steering device, and FIG. 6 is a plan view thereof.

The left and right handles 22L and 22R in this embodiment are
L connected to the tips of the linear grip parts 23L and 23H
It has letter-shaped handle bases 24L and 24R. A pair of left and right handles Brakent 25L fixed to the frame F
, 25R are provided with left and right handle pivots 26L, 26R located on both sides of the steering stem 4, and the handle base 24R of the right handle 22H.
is on the left handle pivot 26L, and the left handle 2
The 2L handle base 24L is the right handle pivot 2
They are each independently pivoted to 6H. The left and right handle bases 24L and 24R are bent inward and intersect vertically at the front positions of the handle pivots 26L and 26R, which are the pivot axes thereof, and are connected to the grip parts 23L and 23R on the opposite side of the steering stem 4. There is. The bent portions of the handle bases 24L, 24H and the front portion of the top bridge 5 are connected to a connecting rod 29 as a link mechanism L whose both ends are pivotally supported by a pin 27 and a pivot 28.
The connecting rods 29L and 29R are connected at the center thereof, and a turnbuckle 30 for length adjustment with reverse threads formed at both ends is attached to the center of the connecting rods 29L and 29R.

The lengths of the left and right handles 22L, 22R, that is, the grip portions 23L, 23R and the handle pivots 26L, 2
The distance of 6R is set longer than the conventional one by the amount of eccentricity e between the steering stem 4 and the handlebar pivots 26L, 26R, and this distance 7F/l/2 2L, 2
2 By increasing the length of R, it becomes possible to obtain a large steering torque. Therefore, the handle 22L. 22
Position P1 at full steering by reducing the R steering stroke
Even if it is set inside the conventional position PI', the distance jliL between the handle pivots 26L, 26R and the pin 27
By setting a large ratio Ll/L2 to the distance L2 between the steering stem 4 and the pivot shaft 28, the turning angle of the handles 22L and 22R can be increased and transmitted to the front wheels Wf. In this way, the handle 22L, 22
Due to the increase in steering torque due to the extension of the R arm length,
Even if the steering strokes of the handlebars 22L and 22H are reduced to avoid interference with the fuel handle T and the fairing C, a sufficient turning angle of the front wheel Wf can be ensured.
Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the embodiments described above, and various small design changes may be made without departing from the scope of the invention described in the claims. It is possible to do so. For example, the specific shapes such as the length and angle of each member constituting the link mechanism L and the handles 9L, 9R, 22L, and 22R are not limited to those of the embodiment, but can be changed as appropriate. Further, the present steering device is applicable not only to motorcycles but also to tricycles.

C. Effects of the Invention As described above, according to the first feature of the present invention, in a region where the steering angle is small, the steering angle is transmitted to the front wheels at a ratio of approximately 1:1, so that normal steering is not required during driving. You can feel it. In addition, in areas where the steering angle is large, the steering angle is magnified and transmitted to the front wheels, so the steering angle corresponding to the required maximum steering angle of the front wheels can be kept small. This prevents interference between the handlebar and the fuel tank and fairing, increasing the degree of freedom in its design. Also, the second aspect of the present invention
According to the feature of , large steering torque can be obtained by extending the length of the steering wheel, so even if the steering angle of the steering wheel is set small, the steering torque can be increased by expanding the steering angle of the steering wheel and transmitting it to the front wheels. This makes it possible to maintain a reasonable turning angle of the front wheels. This prevents interference between the handlebar and the fuel tank and fairing, increasing the degree of freedom in its design.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of a motorcycle equipped with a vehicle steering device according to an embodiment of the present invention, Fig. 2 is a perspective view of the steering device, Fig. 3 is a plan view thereof, and Fig. 4 is a steering wheel turning device. FIG. 5 is a perspective view of a steering device according to another embodiment of the present invention, and FIG. 6 is a plan view thereof. F... Frame, L... Link mechanism, Wf... Front wheel 4... Steering stem, 5... Top bridge, 7... Front fork, 8... Handle bracket, 9L, 9R.・Handle, 10L, 10R・
...Handle base, 11L, 11R...Grip part,
12...Handle pivot, 13L. 13R... Swing link, 17L. 17R...Tension link, 2
0L, 2OR...Connecting rod, 22L, 2
2R...Handle, 23L, 23R...Grip part, 24L. 24R...Handle M part, 25L, 25R
...Handle bracket, 26L, 26R...Handle pivot, 29L, 29R...Connecting rod Patent applicant Honda Motor Co., Ltd. Agent Patent attorney Ken Ochiai Doda Takahide Naka

Claims (1)

[Claims] [1] A front fork (7) is pivotally supported on the frame (F) via a steering stem (4), and a front wheel (Wf) is pivotally supported on the lower part of the front fork (7). , the handle bracket (
8), left and right handles (9L, 10R) consisting of grip parts (11L, 11R) and handle bases (10L, 10R).
9R), and these handlebars and the front fork (
7) are connected by a link mechanism (L), the left and right handle bases (10L, 10R) are independently pivoted to the handle bracket (8) via the handle pivot (12), and The handle pivot (
12) on the rotation axis of the steering stem (4), and connect the link mechanism (L) to the left and right handle bases (
A pair of swinging links (13L, 13R) whose intermediate parts are pivoted to the swinging links (10L, 10R);
, 13R) and a pair of tension links (17L, 17R) that connect the inner ends of the handle bracket (8);
A steering device for a vehicle, comprising a pair of connecting rods (20L, 20R) that connect the outer ends of the swing links (13L, 13R) and a front fork (7). [2] A front fork (7) is pivotally supported on the frame (F) via a steering stem (4), a front wheel (Wf) is pivotally supported on the lower part of the front fork (7), and the frame (F) The handle bracket (
8), left and right handles (9L, 10R) consisting of grip parts (11L, 11R) and handle bases (10L, 10R).
9R), and these handlebars and the front fork (
7) in a vehicle steering system connected by a link mechanism (L), the left and right handle bases (10L, 10R) are independently pivoted to the handle bracket (8) via handle pivots (26L, 26R). At the same time, the handle pivots (26L, 26R) are provided on the left and right sides of the handle stem (4), and the left and right handle bases (24L, 24R) pivoted on the respective handle pivots (26L, 26R) are placed in front of the handle stem (4). on the opposite side of the handle stem (4).
L, 23R) and the link mechanism (L, 23R).
), a pair of connecting rods (2
9L, 29R).