WO2004045941A1

WO2004045941A1 - Front two-wheel type tricycle and front frame used therefor

Info

Publication number: WO2004045941A1
Application number: PCT/JP2002/011951
Authority: WO
Inventors: Kinya Kanou
Original assignee: Kinya Kanou
Priority date: 2002-11-15
Filing date: 2002-11-15
Publication date: 2004-06-03
Also published as: AU2002368372A1

Abstract

A front two-wheel type tricycle, comprising a main frame (2), a steering shaft (7) rotatably pivoted at the front end of the main frame (2), and two front fork members (9) fitted to the steering shaft (7) so as to be rotated integrally with the steering shaft (7) and pivotally supporting front wheels (F) apart from each other in the lateral direction of a body, each of the front fork members (9) further comprising a base part (11) fitted to the steering shaft (7), a front wheel support part (12) longitudinally movably and unrotatably supported on the base part (11) relative to each other and pivotally supporting the front wheel (F), and an elastic member (13) energizing the front wheel support part (12) downward, wherein one front wheel (F) and the other front wheel (F) are formed so that distances thereof from the lower end of the steering shaft (7) are variable, independently of each other, according to loads acting on the front wheels (F).

Description

Description Front two-wheeled tricycle and front frame used for it

The present invention relates to a front two-wheeled three-wheeled vehicle that can be suitably used as a front-wheeled bicycle such as a bicycle for city driving or an off-road bicycle such as a mountain bike, and a front frame used therefor. Background art

For convenience of loading and prevention of overturning, front two-wheel or rear two-wheel three-wheeled bicycles have been put into practical use. On a two-wheeled bicycle, the vehicle body is made lean to resist the centrifugal force acting when turning, but on a three-wheeled vehicle, it is necessary to exert a centripetal force against the centrifugal force.

For this reason, in rear two-wheeled tricycles, a swing is made between the riding part and the rear two-wheel part, and the front wheel part is made lean with the rider. However, in such cases, there are the following problems. That is, the drive chain is easily twisted and disengaged by the swing between the rear two-wheel portion and the front wheel portion. When one of the rear two wheels is a driving wheel, the turning to the driving wheel side causes a phenomenon that the driving wheel is lifted off the road surface, and the driving force is reduced. In addition, since the rear wheel is located behind the rider's view range, the rear wheel can easily climb over obstacles such as road bumps, or there is a danger of falling off.

For this purpose, for example, Japanese Patent No. 253117998 discloses that instead of the rear two-wheeled vehicle, a front two-wheeled three-wheeled vehicle is adopted, We have proposed a tricycle with a mechanism that enables the front wheels to be independently steered and rotated, and generates a centripetal force that opposes the centrifugal force during turning.

Japanese Unexamined Patent Application Publication No. 2000-335056 discloses that the rear two wheels adopt an independent suspension in which the chain stays can move up and down independently so that the rear two wheels can be tilted. The need to swing between the front part and the rear two-wheel part when leaning This has reduced the adverse effects of chain twisting and other problems, and has proposed a tricycle that allows smooth running and turning.

However, the front two-wheeled three-wheeler according to the former proposal has two front wheels that are individually linked to each other to be steerable and rotatable, so that the front wheels rotate in a parallel state around each pivot point like a four-wheeled vehicle. Because of this, the structure is complicated, and when turning, one of the front wheels tends to slip due to the difference in turning radius.

Furthermore, the rear two-wheeled three-wheeled vehicle according to the latter proposal has a complicated device in order to make the chain stay itself swingable up and down, and since this proposal uses one chain drive mechanism, When turning or riding on an obstacle, the driving wheels are likely to idle, which may impair steering stability.

The present invention has been devised in view of the above-described problems, and uses two elastic fork members to provide two front fork members that are rotatably provided integrally with a steering shaft and respectively support the front wheels. Basically, it can be moved up and down independently. As a result, the steering performance and running stability can be improved to solve the above-mentioned problems, and since there is no swing mechanism for the vehicle body, the vehicle can stand still or run at a low speed without landing, and can also reduce the impact at the time of a bump collision. Another object of the present invention is to provide a front two-wheeled three-wheeled vehicle and a front frame used for the same, which can also be used as off-road bicycles such as mountain bikes while improving the ability to ride over projections and run in the city. Disclosure of the invention

The invention according to claim 1 of the present application comprises a main frame, a steering shaft rotatably supported at a front end of the main frame and having a handle at an upper end, and a steering shaft integrated with the steering shaft. A front frame having two front fork members rotatably provided and pivotally supporting the front wheels with the front wheels being separated in the width direction of the vehicle body, wherein each of the front fork members includes a base attached to the steering shaft; A front wheel supporting portion which is supported so as to be relatively movable and non-rotatable in the longitudinal direction with respect to the base portion and which pivotally supports the front wheel; and an elastic member which urges the front wheel supporting portion downward. Connect one front wheel and the other front wheel to the lower end of the steer link shaft. Is independently variable according to the load acting on the front wheel. In the invention according to claim 2, the front fork member has a base portion formed of a shaft-shaped or cylindrical fixed shaft body, and a front wheel supporting portion that is not rotatable relative to the fixed shaft body. A movable or axially-movable cylindrical or shaft-like moving shaft, which pivotally supports the front wheel at the lower end of the moving shaft, and the elastic member comprises a moving shaft. It is characterized in that the body is urged downward.

Further, in the invention according to claim 3, the fork member is characterized in that the base has one fixed shaft body having a non-circular cross section or a plurality of fixed shaft bodies having a non-circular cross section or a circular cross section. I have.

In the invention according to claim 4, the front fork member has a guide portion whose base portion extends downward from a steering shaft, and the front wheel support portion has a relative rotation disabled along the guide shaft of the guide portion. The elastic member biases the slide member downward independently of the other slide member.

In the invention according to claim 5, the guide portion is fixed between an upper holding plate and a lower holding plate at a lower end of a steering shaft, and the front wheel support portion is relatively immovable. It is characterized by comprising one guide shaft each having a non-circular cross section or a plurality of guide shafts each having a non-circular cross section or a circular cross section.

In the invention according to claim 6, the front fork member is formed of a shaft having a base fixed to a steering shaft, and the front wheel support is tiltably attached to the shaft. And an arm-shaped body which is urged downward by an elastic member.

The invention according to claim 7 is characterized in that the front wheel supporting portion includes a brake composed of a braking disk concentric with the front wheel and a braking device for braking a pad.

In the invention according to claim 8, the front wheel support portion is characterized in that its stroke is vertical and the shrinkable amount during traveling is 50 to 250 mm. Further, in the invention according to claim 9, the front fork member includes a panel of the elastic member. It is characterized in that an adjusting means for adjusting the pressure is provided.

In the tenth aspect of the present invention, the two front wheels have a length between the intermediate positions in the tire axial direction of 100 to 500 mm.

Further, in the invention according to claim 11, the elastic member is made of one or a combination of a coil panel, a torsion spring, a plate spring, a pneumatic spring, a hydraulic spring, or a rubbery elastic material. And

Further, in the invention according to claim 12, a steering shaft and two front forks provided on the steering shaft so as to be rotatable integrally with the steering shaft, and each of the front forks pivotally supporting the front wheel with the front wheel separated in the vehicle width direction. The front fork member includes a base mounted on the steering shaft, and is supported relative to the base so as to be relatively movable and non-rotatable in the length direction and to pivotally support the front wheel. A front wheel supporting portion, and an elastic member for urging the front wheel supporting portion downward, the distance between the one front wheel and the other front wheel being independently set to the lower end of the steer link shaft. It is characterized by being variable according to the weight of the front wheel.

Further, in the invention according to claim 13, the front fork member, wherein the base portion is formed of a shaft-shaped or cylindrical fixed shaft body, and the front wheel support portion is not rotatable relative to the fixed shaft body. In addition, the front and rear wheels are pivotally supported at a lower end portion of the movable or axially-movable cylindrical or axially-movable shaft. It is characterized by biasing the body downward.

In the invention according to claim 14, in each of the front fork members, the base has one fixed shaft body having a non-circular cross section or a plurality of fixed shaft bodies having a non-circular cross section or a circular cross section. It is characterized by.

In the invention according to claim 15, the front fork member includes a guide portion whose base portion extends downward from a steering shaft, and the front wheel support portion has a relative position along the guide shaft of the guide portion. The slide member is a non-rotatably guided vertically movable slide body, and the elastic member biases the slide body downward independently of the other slide body.

In the invention according to claim 16, the guide portion is located above a lower end of a steering shaft. One guide shaft each having a non-circular cross section, or a plurality of non-circular or circular cross-section guides, which are fixed between the holding plate and the lower lower holding plate, and guide the front wheel support portion so as to be relatively non-rotatable. And a guide shaft.

Further, in the invention according to claim 17, the front fork member is formed of a shaft body having the base fixed to a steering shaft, and the front wheel support is tiltably attached to the shaft body. And an arm-shaped body which is urged downward by the elastic member. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic perspective view illustrating an embodiment of the present invention,

Figure 2 shows the front view,

Figure 3 shows the left side view,

FIG. 4 is a partial front view illustrating a head pipe portion of the main frame, FIG. 5 is a plan view thereof,

FIG. 6 is a partial front view showing another example of the top pipe portion,

FIG. 7 is a partial cross-sectional view illustrating a front fork member,

FIG. 8 is a left side view illustrating a use state in which the tricycle is upright,

FIG. 9 is a left side view illustrating a state where the tricycle at the step position is upright, FIG. 10 (A) is a left side view illustrating a left turning state,

FIG. 10 (B) shows a diagram illustrating the instantaneous center of the turn,

Fig. 11 (A;) and Fig. 11 (B) are diagrams showing the state when the vehicle crosses the road shoulder. Fig. 12 is a partial left side view illustrating a tricycle equipped with a front fork member. Is a cross-sectional view showing an example of the front fork member,

FIG. 14 is a cross-sectional view showing an example of the front fork member.

FIG. 15 is a sectional view showing an example of the front fork member.

FIG. 16 is a sectional view showing still another example of the front fork member,

FIG. 17 is a left side view showing another example of the front fork member,

FIG. 18 is a partial perspective view illustrating a third embodiment of the present invention 3, FIG. 19 is a perspective view illustrating an embodiment of Invention 2 of the present application,

Figure 20 is a left side view with the front fork vertical.

Figure 21 shows the front view,

FIG. 22 is a perspective view illustrating a front fork member,

FIG. 23 is a front view illustrating a slide body,

Fig. 24 is a partially enlarged partial cross-sectional view of the slide body.

FIG. 25 is a sectional view taken along line X—X of FIG.

FIG. 26 is a left side view illustrating a use state where the tricycle is upright,

FIG. 27 is a left side view illustrating a state where the tricycle at the step position is upright, FIG. 28 (A) is a left side view illustrating a left turning state,

Fig. 28 (B) is a diagram illustrating the instantaneous center of the turn,

FIGS. 29 (A) and 29 (B) are diagrams showing a state when the vehicle crosses the road shoulder, and FIG. 30 is a left side view illustrating an embodiment of the present invention 4;

FIG. 31 is a front view thereof. BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described below with reference to the drawings, taking as an example a case where the present invention is an embodiment of the present invention 1 and the front two-wheeled tricycle is a front two-wheeled three-wheeled bicycle. 1 to 4, a front two-wheeled three-wheeled vehicle (hereinafter referred to as a three-wheeled vehicle 1) of the present invention includes a vehicle body 4 including a main frame 2 and a front frame 3, and the front frame 3 has a handle 6 at an upper end. The steering shaft 7 is provided, and two front fork members 9 are provided on both sides of the steering shaft 7 so as to be rotatable integrally with the steering shaft 7.

The front fork member 9 includes a base 11 attached to each of the steering shafts 7, a front wheel support 12 for pivotally supporting the front wheel F, and an elastic member 1 for urging the front wheel support 12 downward. 3 is provided. As shown in FIG. 3, the two front wheels F, F have a tire axial distance LW of 100 to 500 mm, preferably about 150 to 300 mm, and provide steering stability and turning. Satisfaction with sex. The main frame 2 has, at its front end, a vertical head pipe 21 (shown in detail in FIGS. 2 and 4) for supporting the front frame 3 so as to be steerable, and a saddle pipe 24 for attaching a saddle 22 at an upper end. A rear wheel near the intersection with a back fork 29 extending backward from the saddle pipe 24 and a chain stay 1 (not shown), which are connected by upper and lower connecting pipes 25 and 26 therebetween. Supports R.

In addition, a chain mechanism 30 that pivotally supports the crank shaft near the intersection of the lower end of the saddle pipe 24 and the lower joint pipe 26 and drives the rear wheel R by a crank arm and a pedal is a chain case. It is equipped with a well-known and drive mechanism housed in the vehicle. The main frame 2 may have any configuration.

In the present embodiment, in the present embodiment, as schematically shown in FIGS. 4 and 5, the steering shaft 7 extends through the center of the bottom of the upper and lower connecting plates 32 and 33 in a plane isosceles triangle shape. The handle 6 is fixed to a projecting portion which is fixed and projects upward from the upper connecting plate 32 of the steering shaft 7. In addition, a pivot shaft 36 (shown in FIG. 4) which passes vertically near the hypotenuse intersection of the upper and lower connecting plates 32, 33 is provided between the upper and lower connecting plates 32, 33 by the head pipe 21. The front frame 3 can rotate around the pivot shaft 36 by passing through the shaft. As described above, in the present embodiment, the steering shaft 7 of the front frame 3 is fixed at the center of the bottom of the upper and lower connecting plates 32 and 33, and can be rotated by the head pipe 21.

As shown in FIG. 6, a head pipe 21 is disposed on the upper connecting plate 32, and the handle 6 is provided on an upwardly projecting portion of the steering shaft 7 from the head pipe 21. It can be deformed freely.

In the present embodiment, the front fork member 9 is connected to the upper and lower connecting plates 32, 33, and from near the intersection of both sides of the base and the oblique side of the upper connecting plate 32, the bottom of the lower connecting plate 33 And a base 11 consisting of a shaft-shaped fixed shaft 11A extending downward through the vicinity of the intersection on both sides of the hypotenuse, and a cylindrical shape externally inserted below the fixed shaft 11A. A pair of left and right sides is formed, including a front wheel supporting portion 12 made of a moving shaft-shaped body 12A, and an elastic member 13 for urging the front wheel supporting portion 12 downward. In this way, the base 11 is attached to the steering shaft 7 so as to be able to turn integrally with the steering shaft 7 via the upper and lower connecting plates 32, 33. Further, as shown in FIGS. 3 and 7, the movable shaft-shaped body 12A, which is the front wheel support portion 12, has a front wheel bearing shaft 39 on the lower end portion for pivotally mounting the front wheel F in a cantilever manner. The fixed shaft 11A is inserted into its inner hole 40, the lower end of the fixed shaft 11A, and the upper end of the movable shaft 12A. Due to the sliding bearings 41, 42 provided on the front and rear sides, the front and fork members 9 can be extended and contracted relatively densely and relatively moved in the longitudinal direction, and the front fork member 9 can be expanded and contracted. 1 2 Move A) up and down. In addition, appropriate retaining means (not shown) is provided.

In this embodiment, the base 11 is a rod (shaft) -shaped fixed shaft 11 A, and the front wheel support 12 is a cylindrical moving shaft 12 A. As shown in FIGS. 13, 14 and 14, the base 11 may be cylindrical and the front wheel support 12 may be axial.

Further, the base portion 11 and the front wheel support portion 12 are provided with anti-rotation means 43 for preventing relative rotation. As shown in FIGS. 3 and 7, the detent means 43 is provided on one of the fixed shaft 11A and the movable shaft 12A. It comprises a key groove-shaped concave portion 45 extending and a convex portion 46 provided on the other side and formed of a key-shaped protruding piece fitted into the concave portion 45. The convex portion 46 is locked at the lower end of the concave portion 45 when the base portion 11 and the front wheel support portion 12 are in the maximum extended state. In addition, the convex portion 46 may be formed on the base portion 11 and the concave portion 45 may be formed on the front wheel support portion 12 (not shown). In addition, the concave portion 45 can be formed in a slot shape in which the thickness of the cylindrical body of the front wheel support portion 12 is notched, and at that time, it is preferable to provide a suitable water intrusion prevention means (not shown).

As shown in FIG. 15, the anti-rotation means 43 may be replaced with a key and a keyway, and may use a link mechanism that connects the base portion 11 and the front wheel support portion 12 and can be bent in a rectangular shape as shown in FIG. Also, as shown in FIG. 16, the cross section of the base 11 and the front wheel support 12 can be made non-circular. FIG. 17 also shows a guide shaft portion 7A in which, for example, the steering shaft 7 is extended downward to provide a concave portion 54 having a length more than twice the normal lifting stroke of the front wheel support portion 12. Locking brackets 57, 57 protruding from each front wheel support portion 12 and having a convex portion 46 engaged with the concave portion 54 are provided, and the locking brackets 57, 57 are vertically moved. Aggression The anti-rotation means 43 for preventing the front wheel support portion 12 from rotating by disposing it at a position not to be rotated is disclosed.

FIG. 18 further includes a base 11 composed of a shaft-like body fixed to the steering shaft 7 as described above, for example, as described above, and the front wheel support 12 is attached to the lower end of the shaft-like body. It discloses an embodiment of the "invention 3" of the present invention comprising an arm-shaped body 12B that is tiltably attached and urged downward by an elastic member 13. Thus, an arm-shaped body is provided at the lower end of the shaft-shaped body. The body 12B can be tilted only in one plane (for example, a vertical plane passing through the vehicle body center line or a parallel plane thereof with the vehicle body being vertical), so that the steering shaft 7 and the front fork member 9 are prevented from rotating. Detent means 4 3 can also be used.

Further, as shown in FIGS. 3 and 7, the elastic member 13 is disposed between the base 11 and the front wheel support 12 and is made of, for example, a coil panel. The elastic member 13 has its upper end abutted on the lower end of the base 11 and its lower end located at the bottom of the front wheel support portion 12, and is compressed and stored, as described above. The base portion and the front wheel support portion 12 are urged to extend. As shown in FIGS. 12, 13, and 14, when the base 11 is cylindrical, the lower end of the base 11 is pressed, for example, as if pressing the shaft-shaped front wheel support 12 at the lower end. A flexible member 13 such as a coil spring can be stored in the housing.

The elastic member 13 can also include a panel pressure adjusting means 50 for changing the spring force, as illustrated in FIG. In the case of FIG. 14, the spring pressure adjusting means 50 includes an adjusting shaft 52 that can freely rotate the closing plate 51 that closes the upper end of the base 11 and that is appropriately stopped such as a step, a retaining ring, and the like. The nut member 5 is screwed to the screw portion of the nut portion. The elastic member 13 is expanded and contracted by the reciprocation of the nut member 54 by the rotation of the adjustment shaft 52, and the spring force can be adjusted.

In addition, the elastic member 13 can be used according to the rider's weight, leg strength, vehicle weight, and usage conditions such as general vehicles, sport vehicles, mountain bikes for traveling on wasteland, cargo vehicles, and small vehicles. Usually, a coil spring having a relatively weak spring constant of about 1.5 to 7.5 NZmm Z pieces, preferably about 2.0 to 5.5 N / mm pieces is selected and used. Depending on the conditions of use, it is possible to run the front wheel F from the upper end of the front fork member 9 If the amount of shrinkage is in the range of 50 to 250 mm, preferably 100 to 200 mm, and the applied load (including impact load) depending on the operating conditions may increase, It is good to choose a large amount. As a result, in the event of collision with a rock on a rough terrain or a road shoulder during city driving, the spring is compressed, reducing the length from the upper end of the front fork member 9 to the front wheel F, causing a large impact on the front wheel F. Without this, the front wheel F can be lifted up and overridden, and the impact can be reduced to prevent a fall. Also, when a collision is made diagonally to the road shoulder, the front wheel F on the collision side is lifted up, while the other is installed normally, thereby significantly reducing the fall as described above, and the collision from the front. At the same time, it will improve the ability to get over projections.

In addition, even when the rider is not traveling, the weight of the rider and the amount of stationary settlement due to the inclination by gripping the handle can be set to, for example, 10 to 150 mm, preferably about 20 to 150 mm. . It can be 20 to 50 mm. When traveling on rough terrain, the amount of stationary settlement is increased to prevent separation between the front wheel F and the running surface to prevent hand breakage. This adjustment is performed by adjusting the initial compression amount of the elastic member 13. For this, a panel having different specifications can be used, or an appropriate adjusting means such as a spring pressure adjusting means 50 shown in FIG. 14 can be used. It is also possible to use multiple types of springs with different strengths in a vertical joint, and to use interchangeable auxiliary wheels that change part of the panel. Also, when a large reaction force acts on the front wheel F, it is preferable to use an elastic member 13 having a large panel constant to absorb the impact, and a material such as rubber can be used.

In such a three-wheeled vehicle 1, in the non-riding state, as shown in FIG. 8, the front fork member 9 is in the maximum extension state due to the elastic member 13 and the left and right front wheels F, F have the same height. And, by separating the tire axial distance LW, the steering wheel can be upright and stationary, for example, by locking in the front running direction. In addition, an appropriate brake means that operates when the vehicle is stationary can be provided. In addition, it enables low-speed running. In addition, the front two wheels allow the rider to drive the bicycle safely while clearly seeing the unevenness of the road surface on which he / she runs.

Further, when there is a step G on the road surface during traveling, as shown in Fig. 9, The front fork member 9 expands and contracts by the member 13 and also against the elastic member 13 to absorb and mitigate shocks when riding, thereby improving ride comfort. By adjusting the load acting on the front wheel F due to the movement, traveling in an upright state is possible.

Also, when turning, as shown in Fig. 10 (A), the vehicle body 4 can be leaned without using the swing means to separate the front wheel and the rear wheel, and the rider can easily resist the centrifugal force. The body can be turned inward while turning. In addition, since the front wheels F, F are separated from the body center line on both sides, even if the rider leans inward during turning, the amount of the center of gravity protruding outside the inside front wheel F decreases, Side slip is reduced. Since the front frame 3 rotates 0 as a unit, as shown in Fig. 10 (B), the distance between the axle line of the front wheels F 1 and F 2 and the axle line of the rear wheel R from the instantaneous center C is determined. As the front wheels Fl and F2 can move forward and backward to adjust the speed, slippage of the wheels during turning is reduced and power loss is reduced compared to a four-wheeled vehicle mechanism that forcibly steers each front wheel. It is thought that the vehicle can turn smoothly.

Furthermore, as shown in Fig. 11 (A), when the three wheels 1 collide with the roadside D, etc., the panel load of one of the collided front wheels F 1 is relatively small, and Since the front wheel F 2 remains without riding, the stability is maintained, and only the one front wheel F 1 is lifted against the elastic member 13 and lands on the road shoulder D (FIG. 11 (B )) To get on the shoulder D. Further, the other front wheel F2 is also held by the preceding front wheel F1, and can easily get on continuously, and can relatively easily get over without falling over like a normal motorcycle.

In this way, smooth city driving on rough terrain becomes possible. The fixed shaft 11A and the movable shaft 12A of the front fork member 9 can be omitted in number by arranging a plurality of them in parallel.

FIGS. 19 to 28 show an embodiment of the "invention 2" of the present invention, taking a case where the front two-wheeled tricycle is a mountain bike as an example. The tricycle 1 is composed of a main body 2 and a front frame 3, The front frame 3 includes a steering shaft 7 provided with a handle 6 at an upper end, and the steering shaft 7 on both sides of the steering shaft 7. It has two front fork members 9, 9 which are provided so as to be rotatable integrally with the steering shaft 7 and can be steered. The front fork members 9, 9 have two front wheels F, F having a widthwise interval LW of 100 to 500 m, preferably about 150 to 300 mm. . Note that FIGS. 20 to 24 show the front frame 3 which is actually mounted at an angle in a vertical direction.

The main frame 2 has, at its front end, a vertical head pipe 21 (shown in FIG. 19) for supporting the front frame 3 so as to be steerable, and a saddle pipe 24 for attaching a saddle 22 at the upper end. And a back fork 29 extending from the head pipe 21 to the center of the rear wheel, a connecting pipe 26 extending from the head pipe 21 to the vicinity of the center of the front wheel F, and pivotally connected to the connecting pipe 26. The rear wheel R is supported near the intersection of the chain stay 27 extending rearward and the back fork 29.

Furthermore, a well-known chain mechanism that pivotally supports the crankshaft near the intersection of the joint pipe 26 and the chain stay 27 near the lower end of the saddle pipe 24 and drives the rear wheel R by a crank arm and a pedal. A speed change drive mechanism is provided. In this embodiment, which is a mountain bike, a spring material 29a is interposed between the back forks 29 to enable the rear wheel R to move up and down and eliminate the chain cover.

Further, the steering shaft 枢 is rotatably supported by the head pipe 21, and the front fork member 9 is provided at a lower end thereof. The front fork member 9 includes a base 11 of the steering shaft 7, which includes a guide portion 11 B attached to a lower end in the present embodiment and extending downward, and a guide shaft 11 a of the guide portion 11 B, The front wheel support section 12 consisting of a slide body 12 C that can be moved up and down guided relative to the relative rotation along the lib, and this slide body 12 C faces downward independently of the other slide body 12 C It is formed by the elastic member 13 which urges against.

As shown in FIGS. 20 to 23, the guide portion 11B is provided between an upper holding plate 14A formed at the lower end of the steering shaft 7 and a lower holding plate 14B. A highly rigid frame body in which the guide shafts 11a and 11b are firmly fixed in two rows in front and rear and left and right. In this embodiment, the guide shafts 11a and 11b are formed using a tubular body having a circular cross section.

Further, as shown in FIGS. 22 to 25, the slide body 12C is a block body through which guide holes 14a, 14b before and after passing through the guide shafts 11a, 11b pass vertically. A cantilevered front wheel support shaft 19 (FIG. 25) for rotatably supporting a front wheel F that cantileverly projects outward and a disk 17a integral with the front wheel F; ) Is mounted, and a brake 17b having a pad for braking the disk 17a is attached. The disk 17a and the brake 17b constitute a braking means 17.

As shown in FIG. 24, the guide holes 14a and 14b are prevented from falling off by a seal 18a for removing dust and water, a retaining ring 18b inside the retaining hole 18a, and the retaining ring 18b. A dust-removing lubricating tool 18A composed of an oil-impregnated portion 18c made of felt and the like held up and down by a hard ring and a sliding bearing 18B composed of an oil-impregnated material such as resin or sintered metal are arranged vertically symmetrically. . The two slides 18C for supplying lubricant communicate with the cut-off portion of the central slide bearing 18B, whereby each slide body 12C is always smoothly guided by the guide shafts 11a and 11b. Can slide smoothly. The seal 18a is prevented from coming off by the holding plate 18D.

The elastic member 13 is formed of a coil spring, is externally inserted into the rear guide shaft 11b, interposed between the lower surface of the upper holding plate 14A and the upper surface of the slide body 12C, and Is urged downward.

The elastic member 13 can be the same as that used in the above-described embodiment. For example, it is generally 1.5 to 7.5 N / mm / piece, preferably 2.0 to 5.5 N, depending on the use conditions. Select a coil spring with a relatively weak panel constant of about / mm / piece and, according to the conditions of use, the amount of shrinkage possible when the front wheel F is running from the upper end of the front fork member 9 is 5 to 250 mm, preferably The range is 100 to 200 mm.

Note that even when the rider is not traveling, the weight of the rider and the amount of stationary settlement due to the inclination by gripping the steering wheel can be set to, for example, 10 to 150 mm, and preferably about 20 to 150 mm. It can be 20 to 50 mm. Wasteland driving At times, the amount of the stationary settlement is increased to prevent the front wheel F from separating from the running surface to prevent the vehicle from falling down. This adjustment is performed by adjusting the initial compression amount of the elastic member 13. For this, a panel having different specifications can be used, or an appropriate adjusting means such as the spring pressure adjusting means 50 shown in FIG. 14 can be used. It is also possible to use multiple types of panels with different strengths in a longitudinal connection, and it is also possible to use replaceable auxiliary wheels that change part of the panels. Also, as shown in Fig. 22, two types of coil springs 13U and 13L having the same diameter but different spring constants may be used, and a spring having a large panel constant is used as the shorter side spring. Thus, a large load at the time of abutment can be buffered, and the panel constant on the short side is 1.2 to 2.5 times, preferably 1.4 to 2.0 times the panel constant on the long side. In addition, the shock absorber 20 is also arranged on the lower surface of the slide body 12C, so that the impact at the time of abutment between the slide body 12C and the lower holding plate 14B can be reduced.

Thus, in the tricycle of the invention 2 of the present application, the front wheel F slides on the guide shafts 1 la and 11 b of the mating interior 11 A, which is the base 11, as the slide body 12 C as the front wheel F. In contrast to the three-wheeled vehicle according to Invention 1 of the present invention, the base 11 is a fixed shaft 11 A, and the front wheel support 12 is a moving shaft 12 A, Although the two units differ in their telescopic expansion and contraction, their basic operation does not differ.

That is, FIG. 26 is a diagram corresponding to FIG. 8 showing the upright state of the vehicle body 4, FIG. 27 is a diagram corresponding to FIG. 9 during the step running, and FIGS. 28 (A) and (B) are turning. Fig. 10 (A) and (B) correspond to Fig. 10 (A) and (B), and Figs. 29 (A) and (B) correspond to Figs. 11 (A) and (B). Can be demonstrated.

In this embodiment, the front wheel F has a smaller diameter than the rear wheel R. For example, a 20-inch front wheel F is adopted for the standard 26-inch rear wheel R of a mountain bike, and the wheel F is at most 24 inches or less. As a result, even if the front wheel F located right and left from the center line is further swung left and right by operating the steering wheel, the front wheel F does not interfere with the rotational operation range of the pedal, and the intense steering operation particularly on off-road is facilitated.

In the present embodiment, the base 11 has two guide shafts 11a and 11b. The base 11 may be provided with three or more guide shafts 11a, or one guide shaft 11a may be used. However, in the case of one guide shaft 11a, the cross-sectional shape of the guide shaft 11a is made elliptical or rectangular, the keyway is formed, etc., so that the relative rotation between the base 11 and the front wheel support 12 is prevented. A detent means is provided.

Further, as the front fork member 9, various mechanisms can be adopted, for example, a parallel crank mechanism having the steering shaft as one link formed on both sides of the steering shaft and the front movable wheel pivotally supported by the vertical movable link, Further, as the elastic member 13, deformation such as using one or a combination of a torsion panel, a plate panel, and a rubber elastic material in addition to the coil spring, the air, and the hydraulic panel is also possible.

In this embodiment, a disc brake is used for the braking means 1, but a caliper type brake can also be used.

FIGS. 30 and 31 show an embodiment of the present invention 4 丄 relating to a front frame used for a front two-wheeled three-wheeled vehicle, in which a steering shaft 7 and two front fork members 9 provided integrally with the steering shaft 7 are provided. The front fork members 9, 9 have two front wheels F, F, an interval LW in the width direction of 100 to 50 Oimn, preferably 150 to 30 Omn. The front fork member 9 has a guide portion having guide shafts 1 la and 11 b between an upper holding plate 14 A at the lower end of the steering shaft 7 and a lower holding plate 14 B at the lower side. A base part 11 composed of 11 B, a front wheel support part 12 composed of a slide body 12 C which is guided along the guide part 11 B so as to be relatively non-rotatable and can move up and down, and a slide body 12 C of The other slide body 12 C is formed by an elastic member 13 urged downward independently of the other slide body 12 C. The distance between the wheel F and the other front wheel F and the lower end of the steering shaft 7 is independently variable according to the load applied to the front wheel F.

In the present embodiment, the base portion 11 is formed using two guide shafts 11a and 11b having a circular cross section. However, the base portion 11 includes three or more guide shafts 11a, or one guide shaft. The base 11 can also be constituted by the shaft 11a. However, in the case of one guide shaft 11a, the relative rotation of the base 11 and the front wheel support 12 such as forming the cross-sectional shape of the guide shaft 11a into an elliptical shape or a rectangular shape, forming a key groove, etc. Is provided. The slide body 12C rotatably supports a front wheel F and a disk 17a integrated with the front wheel F in a block body which is guided by the guide shafts 11a and lib and can move up and down. It has a front wheel support shaft 19 that protrudes outward in a cantilever manner.

The front frame according to Invention 4 of the present application can form a front two-wheeled three-wheeled vehicle by assembling with the main frame. For example, it constitutes a main part of the front two-wheeled three-wheeled vehicle shown in FIGS. Not only do not touch the ground, but also make it possible to run at rest or at very low speed. It can be suitably used.

Further, similarly to the front two-wheeled three-wheeled vehicle of the invention 1 of the present invention shown in FIGS. 1 and 7, a base 11 composed of a shaft-shaped fixed shaft 11A and a lower end portion pivotally support the front wheel and fix the front wheel. A front fork member 9 composed of a movable shaft member 12A that is externally non-rotatably and expandably and contractably attached to the shaft member 11A and is urged downward by the elastic member 13 can also be used. Each front fork member & can be modified such that the base portion 11 includes one fixed shaft body 11 A having a non-circular cross section or a plurality of fixed shaft bodies 11 A having a non-circular cross section or a circular cross section. Further, similarly to the front two-wheeled three-wheeled vehicle according to the third aspect of the present invention shown in FIG. 18, a shaft-shaped base 11 fixed in a steering manner, and a downwardly-slidingly mounted to the base 11 in a tiltable manner. It is also possible to employ a front fork member 9 having a front wheel support portion 12 composed of an arm-like body biased by the member 13.

As described above, the front two-wheeled three-wheeled vehicle of the present invention can stand upright and stand still, can reduce the impact in the event of a collision with a stone, a step, or the like, enhances riding comfort, prevents overturn, and can easily get over. Also, when turning, as with a normal motorcycle, the vehicle can lean without using the swing means that separates the front and rear wheels, and the rider can easily lean inside and turn when opposing the centrifugal force. . In addition, the front fork member expands and contracts on the shoulder of the road to reduce the impact of one of the front wheels when riding, and also makes it easy for the other front wheel to ride.

Further, when configured as in claim 2, the front wheel can be moved up and down on a straight line, and the relationship between the amount of expansion and contraction and the panel reaction force can be made primary, thereby facilitating panel setting. In addition, when configured as in claim 3, braking of the front wheels is ensured, and the handle operation is smooth.

When configured as in claim 4, control of the distance from the lower end of the steering shaft to the front wheels is smooth.

Further, when configured as in claim 5, the rigidity of the front fork member is increased.

In addition, when configured as in claim 6, the structure can be simplified and the cost can be reduced.

In addition, when the vehicle is configured as in claim 7, traveling braking can be smoothed and safety can be ensured. Industrial applicability

As described above, the front two-wheeled three-wheeled vehicle according to the present invention and the front frame used for the two-wheeled three-wheeled vehicle are provided with two front fork members that are rotatably provided integrally with the steering shaft and that respectively support the front wheels. Basically, it can be moved up and down independently. This improves steering performance and running stability and solves the conventional problems.Without the vehicle's swing mechanism, it enables stationary or low-speed running without landing, and reduces the impact of a bump collision. In addition to improving the ability to ride over protrusions, it can be suitably used as an off-road bicycle such as a mountain bike as well as running in the city.

Claims

The scope of the claims

1. A steering shaft rotatably supported at the front end of the main frame and the main frame of;!: And having a handle at the upper end, and provided on the steering shaft so as to be rotatable integrally with the steering shaft; A front frame having two front fork members for pivotally supporting the front wheels in the width direction of the vehicle body, wherein each of the front fork members has a base attached to the steering shaft; A front wheel supporting portion that is supported so as to be relatively movable and relatively unrotatable in the length direction and that pivotally supports the front wheel; and an elastic member that urges the front wheel supporting portion downward, the one front wheel; A front two-wheeled three-wheeled vehicle, wherein the distance between the other front wheel and the lower end of the steer link shaft is independently variable according to the load acting on the front wheel.

2. In the front fork member, the base portion is formed of a shaft or a tubular fixed shaft, and the front wheel supporting portion is inserted or removed so as to be relatively non-rotatable and extendable relative to the fixed shaft. The front wheel is pivotally supported at a lower end portion of the moving shaft, and the elastic member biases the moving shaft downward. The front two-wheeled three-wheeled vehicle according to claim 1, wherein:

3. The said each fork member, The said base part has each one non-circular cross-section, or non-circular cross-section or several fixed axial body of circular cross-section, The said Claim 2 characterized by the above-mentioned. Front two-wheeled tricycle.

4. The front fork member comprises a guide portion whose base extends downward from the steering shaft, and the front wheel support portion comprises a slide member which is guided along the guide shaft of this guide portion so as to be relatively non-rotatable and can move up and down. The front two-wheeled three-wheeled vehicle according to claim 1, wherein the elastic member biases the slide body downward independently of the other slide body.

5. The guide portion is fixed between the upper holding plate at the lower end of the steering shaft and the lower holding plate below, and each guide shaft has a non-circular cross-section for guiding the front wheel supporting portion so as to be relatively non-rotatable. 5. The front two-wheeled three-wheeled vehicle according to claim 4, comprising a plurality of guide shafts having a non-circular cross section or a circular cross section.

6. The front fork member is formed of a shaft having the base fixed to a steering shaft, and the front wheel support is tiltably attached to the shaft and urged downward by an elastic member. The front two-wheeled three-wheeled vehicle according to claim 1, characterized in that the front two-wheeled three-wheeled vehicle comprises an arm-shaped body. '

7. The front two-wheeled three-wheeled vehicle according to claim 1, wherein the front wheel supporting portion includes a brake formed of a braking disk concentric with the front wheel and a brake for braking a pad. '

8. The front two-wheeled three-wheeled vehicle according to claim 1, wherein the front wheel supporting portion has a stroke that is vertically movable and a shrinkable amount during traveling is 50 to 250 mm.

9. The front two-wheeled three-wheeled vehicle according to claim 1, wherein the front fork member is provided with adjusting means for adjusting a spring pressure of the elastic member.

10. The front two-wheeled three-wheeled vehicle according to claim 1, wherein the two front wheels have a length between the intermediate positions in the tire axial direction of 100 to 500 mm.

11. The elastic member according to claim 1, wherein the elastic member is made of one or a combination of a coil panel, a torsion spring, a leaf spring, a pneumatic spring, a hydraulic spring, or a rubbery elastic material. The front two-wheeled three-wheeled vehicle described in the paragraph.

1 2. The steering shaft and the steering shaft can rotate integrally with the steering shaft. And two front fork members pivotally supporting the front wheels at intervals in the vehicle body width direction. Each of the front fork members has a base attached to the steering shaft, and a length relative to the base. A front wheel supporting portion that is supported so as to be relatively movable in the direction and relatively unrotatable and that pivotally supports the front wheel, and an elastic member that urges the front wheel supporting portion downward, the one front wheel and the other A front frame, wherein a distance between a front wheel and a lower end of a steer link shaft is independently variable according to a load applied to the front wheel.

13. The front fork member, wherein the base portion is formed of an axial or cylindrical fixed shaft, and the front wheel support portion is inward or outward so that it cannot rotate relative to the fixed shaft and can contract. And a lower end portion of the movable shaft body pivotally supports the front wheel, and the elastic member urges the movable shaft body downward. 13. The front frame according to claim 12, wherein:

14. The front fork member, wherein the base has one fixed shaft body having a non-circular cross-section or a plurality of fixed shaft bodies having a non-circular or circular cross-section. The front frame described in the item.

15. The front fork member includes a guide portion whose base extends downward from the steering shaft, and the front wheel support portion is guided along the guide shaft of the guide portion so as to be incapable of relative rotation and can move up and down. The front frame according to claim 12, wherein the front frame comprises a slide body, and the elastic member urges the slide body downward independently of the other slide body.

16. The guide portion is fixed between an upper holding plate at the lower end of the steering shaft and a lower holding plate at a lower portion, and each guide has a non-circular cross-section for guiding the front wheel supporting portion so as to be relatively non-rotatable. 16. The front frame according to claim 15, wherein the front frame comprises a shaft, or a plurality of guide shafts having a non-circular cross section or a circular cross section.

17. The front fork member is formed of a shaft having the base fixed to a steering shaft, and the front wheel support is tiltably attached to the shaft and urged downward by an elastic member. 13. The front frame according to claim 12, wherein the front frame is formed of an arm-shaped body.