JP3479946B2 - Oscillation restoration mechanism of tricycle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front frame of a three-wheeled bicycle in which a front frame for supporting front wheels and a seat is configured to be swingable left and right with respect to a rear frame for supporting rear two wheels. The present invention relates to an oscillating restoring mechanism for returning to the state.

[0002]

2. Description of the Related Art As a three-wheeled bicycle, in order to facilitate its turning, a front frame supporting front wheels and a seat is swingable left and right with respect to a rear frame supporting two rear wheels. The one of the formula is known. In such a swing-type three-wheeled bicycle, the front frame is restored to the neutral state during straight running after swinging the front frame to the left or right and turning, and the front frame is stopped when the vehicle is stopped or running straight. A swing restoring mechanism for holding the neutral state is provided.

By the way, as the swinging restoring mechanism, one using a torsion bar shown in FIG.
7946 gazette), the one which adopted the Knighthart mechanism shown in FIG. 9 (see Jpn. Pat. Appln. KOKAI No. 2-37673), etc. are known.

That is, in the swing restoring mechanism shown in FIG. 8, the front frame 1 is attached to the swing shaft 136 fixed to the rear frame 106 side.
04 is swingably supported to the left and right, and the torsion spring 146 wound around the swing shaft 136 is used to rotate the front frame 10
When the front frame 104 swings left or right about the swing shaft 136, the front frame 104 receives a restoring force from the torsion spring 146. At this time, one end of the torsion spring 146 is received by the stopper 151.

The swing restoring mechanism shown in FIG. 9 includes a front frame 204 including a pair of left and right pipe frames.
To the prismatic swing shaft 236 fixed to the rear frame side.
It is configured to be elastically supported so as to be capable of swinging via one Neilhard rubber 246, and when the front frame 204 swings to the left and right, the Neilhard rubber 246 is deformed and a restoring force is generated therein.

[0006]

However, in the swing restoring mechanism shown in FIG. 8, the stopper 151 needs to have a large diameter to increase its rigidity in order to receive the reaction force of the torsion spring 146. Because of the stopper 151, there is a problem that the space between the front frame 104 and the swing shaft 136 is widened to increase the vehicle height, and as a result, the luggage space is reduced.

Further, in the swing restoring mechanism shown in FIG. 9,
There is a problem that the Nighthard rubber 246 is deformed due to deterioration over time, its original restoring function is impaired, and rattling occurs near the neutral point.

The present invention has been made in view of the above problems. The object of the present invention is to suppress the vehicle height to a large space for a cargo bed and to accurately determine the neutral point mechanically. Another object of the present invention is to provide a rocking restoration mechanism for a three-wheeled bicycle that can always maintain a stable restoration function.

[0009]

In order to achieve the above object, the invention according to claim 1 is such that a front frame supporting a front wheel and a seat is swingable left and right with respect to a rear frame supporting two rear wheels. in swinging restoring mechanism for restoring the previous frame tricycle comprising constituting a neutral state, the serial before
Place the frame in the center of the vehicle width direction along the longitudinal direction of the vehicle.
Lead pipe of the main pipe
Immediately below, fixed to either the front frame or the rear frame
The rocking shaft is placed on the other side of the front frame or the rear frame.
A bearing pipe that pivotally supports the swing shaft is arranged in the center of the vehicle width direction.
By doing so, the front frame is centered on the swing axis.
Support the rear frame so that it can swing left and right.
To the vertical <br/> end by shaft support provided on the downward rotatably provided axially supported by a pair of levers to the rear frame, through between the rear frame and the levers of the pivot axis The left and right springs are mounted to urge both levers in opposite rotation directions about the shaft support portion of one end of the levers so that the other end of each lever abuts the main pipe, and the middle portion of each lever abuts. The stopper pipe should be composed of the bearing pipe
Characterized in that it was.

[0010] Further, an invention according to claim 2, wherein, in the invention according to the first aspect, to urge the lever on the left side in the right spring, the upper end of the urging to the levers on the right side of the lever on the left side of the spring It is characterized in that the main pipe is clamped from both sides by a section.

Further, the invention according to claim 3 is characterized in that, in the invention according to claim 1 or 2, a stopper for restricting right and left swing of the front frame is provided on the rear frame.

Therefore, according to the first or second aspect of the invention, the left and right swings of the front frame are restored by the left and right independent springs, respectively, so that the springs are unlikely to suffer from settling due to secular change, and are always A stable restoration function can be maintained. Further, by disposing the pivotal fulcrum of the lever below the swing shaft, it is possible to suppress the vehicle height to a low level and to expand the load carrier space secured on the rear frame. Further, the neutral point of the front frame is not determined by the balance of the urging force (spring force) of the left and right springs, but the pair of left and right levers are urged by the springs in opposite rotation directions, and the middle portion of each lever is urged. Is determined by abutting the stopper on the rear frame side, the biasing forces of the springs do not affect each other, the neutral point of the front frame is mechanically determined accurately, and the spring Adjustment of preload becomes easy.

According to the third aspect of the present invention, the left and right swing angles of the front frame are restricted by the stopper within a predetermined range, so that high stability of the vehicle body is ensured.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of a three-wheeled bicycle equipped with a swing restoring mechanism according to the present invention, FIG. 2 is a partial plan view showing a body frame structure of the rear portion of the three-wheeled bicycle, FIG. 3 is a partial side view of the same, and FIG. 3 is a sectional view taken along the line AA of FIG. 3, FIG. 5 is a perspective view of the swing restoring mechanism according to the present invention, and FIGS. 6 and 7 are explanatory views showing the neutral state and the swinging state of the swing restoring mechanism, respectively. .

First, the schematic structure of the three-wheeled bicycle 1 shown in FIG. 1 will be described. The three-wheeled bicycle 1 is an auxiliary power type electric bicycle, which is driven by receiving auxiliary power corresponding to the pedaling force of an occupant. .

The three-wheeled bicycle 1 according to this embodiment is of a swing type, and the front frame 4 supporting the front wheels 2 and the seat 3 swings with respect to the rear frame 6 supporting the rear two wheels 5. It is configured to be movable, and its return to the neutral state is performed by the swing restoring mechanism 10 according to the present invention.

By the way, the front frame 4 has a head pipe 7 located in front of the vehicle body, and a handle stem 8 is rotatably inserted through the head pipe 7. And
A handle 9 is attached to the upper end of the handle stem 8, and a front fork 11 is attached to the lower end of the handle stem 8. The front wheel 2 is rotated by a front axle 12 at the lower end of the front fork 11. Freely supported. The upper half of the front wheel 2 is covered by the front fender 13.

Further, the front frame 4 has a large-diameter main pipe 14 extending from the head pipe 7 toward the rear of the vehicle body at the center in the vehicle width direction, and a power unit is provided in the front half of the main pipe 14. 15 and controller 52
Are attached, and these are covered by an upper cover 53a and a lower cover 53b. The seat 3 is supported on the upper end of a seat pipe 16 erected on the main pipe 14, and an outer box 17 is provided below the seat 3 along the seat pipe 16. An openable / closable lid 17a is provided on the upper portion of the outer box 17, and by opening the lid 17a, an inner box (not shown) accommodating a battery can be taken in and out of the outer box 17. .
1 and 2, 54 is a pair of left and right seat stays.

Thus, the power unit 15 has a pedaling force detecting means (not shown) for detecting the pedaling force of the occupant inputted to the crankshaft 20, and the controller so as to generate auxiliary power corresponding to the detected pedaling force. The electric motor 55 controlled by 52, a combination force mechanism (not shown) for combining pedal force and auxiliary power, and the like are unitized, and the pedal force applied to the pedal 18 by the occupant passes through the crank 19 and the crankshaft 20.
Is transmitted to the rear wheel 5 supported by the rear frame 6.

That is, the endless chain 2 is provided between the sprocket 21 connected to the crankshaft 20 and the sprocket 23 connected to the intermediate shaft 22 supported by the rear frame 6.
4 is wound, and another sprocket 25 is attached to the intermediate shaft 22 and a sprocket 2 is attached to one rear axle 26.
An endless chain 28 is wound between 7 and the driving force is transmitted from the crankshaft 20 to the intermediate shaft 22 via the sprocket 21, the chain 24 and the sprocket 23, and further from the intermediate shaft 22 to the sprocket 25 and the chain. Two
8 and the sprocket 27 and is transmitted to one rear axle 26, and the rear axle 26 and one rear wheel 5 attached to this rear axle 26.
Is driven to rotate and the three-wheeled bicycle 1 is made to run. That is, the three-wheeled bicycle 1 according to the present embodiment employs the one-wheel drive system.

On the other hand, the rear frame 6 is, as shown in FIGS. 2 to 4, a bearing pipe 35 extending in the front-rear direction at the center portion in the vehicle width direction and a substantially rectangular pipe frame shape welded to the lower surface thereof. It is configured to include a luggage carrier 29, a cross pipe 33 that is laid across the luggage carrier 29, and substantially oval fender frames 30 that are bonded to the left and right ends of the luggage carrier 29. Between two front and rear cross pipes 3
1, 32 are installed. As shown in FIG. 1, each fender frame 30 is arranged so as to surround each rear wheel 5, and a rear fender 34 that covers the upper half of the rear wheel 5 is attached to the fender frame 30. Also, a pair of left and right brackets 3 are provided on the cross pipes 31 and 32.
1a and 32a are respectively bonded, and the basket 56 shown in FIG. 1 is attached to these brackets 31a and 32a by bolts and nuts (not shown).

By the way, as shown in FIGS. 2 and 3, the bearing pipe 35 of the rear frame 6 is arranged immediately below the main pipe 14 on the front frame 4 side.

The front frame 4 is supported by the bolt-shaped swing shaft 36 inserted through the bearing pipe 35 so as to be swingable right and left with respect to the rear frame 6. That is,
Two front and rear brackets 37, 38 are attached to the rear portion of the main pipe 14 on the front frame 4 side, and both brackets 37, 38 are fixed by a nut 39 to the swing shaft 36 inserted through the bearing pipe 35. . Therefore,
The front frame 4 is supported by the rear frame 6 so as to be swingable right and left about a swing shaft 36. 2 and 3, reference numeral 40 denotes a bracket that supports the rear axle 26, one of which is welded to the bearing pipe 35.

As described above, the front frame 4 is rear frame 6
The rocking restoring mechanism 10 according to the present invention is provided between the front frame 4 and the rear frame 6, though the rocking restoring mechanism 10 is swingably supported to the left and right.

Here, details of the structure of the swing restoring mechanism 10 according to the present invention will be described with reference to FIGS.

The swing restoring mechanism 10 has a pair of left and right levers 41, 42 arranged so as to sandwich the main pipe 14 and the bearing pipe 35 from both sides at the center portion in the vehicle width direction. , 42 are rotatably supported on the rear frame 6 side by a bolt-shaped support shaft 43 so as to be rotatable left and right. That is, as shown in detail in FIG. 5, two lugs 44 are connected to the lower portion of the bearing pipe 35 in the front-rear direction, and the lower ends of the left and right levers 41 and 42 are attached to the nut 4
5, it is rotatably supported by the support shaft 43 attached to the lug 44 .

The left and right levers 41 and 42 are
A pair of left and right springs 46 and 47 interposed with an appropriate preload between the intermediate portion and the platform 29 are urged in opposite directions about the support shaft 43. That is, the left lever 41 is urged in the clockwise direction in FIG. 4 by the right spring 46 interposed between the middle portion of the left lever 41 and the bracket 48 connected to the luggage carrier 29, and the right lever 41 is The lever 42 is urged in the counterclockwise direction in FIG. 4 by a spring 47 on the left side interposed between an intermediate portion of the lever 42 and a bracket 49 connected to the carrier 29.

By the way, the upper and lower end portions 41a and 42a of the left and right levers 41 and 42 and the intermediate portion (springs 46 and 4) are formed.
41b and 42b are bent at a right angle to form a flat contact portion. As described above, the left and right levers 41 and 42 are supported by the springs 46 and 47 to support the spindle 43. When the three-wheeled bicycle 1 is stopped and is traveling straight ahead, the left and right levers 41 and 42 have upper end portions 41a and 42a, as shown in FIG. The main pipe 14 on the fourth side is clamped from both sides to keep it in a neutral state. At this time, the intermediate portion 41 of the left and right levers 41, 42
As shown in FIG. 6, b and 42b come into contact with the bearing pipe 35 that constitutes the stopper portion to prevent the levers 41 and 42 from further rotating. Although not shown in FIGS. 6 and 7, the lever 4 is provided on both sides of the main pipe 14.
A resin receiving member 50 to which the upper end portions 41a and 42a of the first and the second portions 42 and 42 abut is bound.

As described above, in the present embodiment, the neutral point of the front frame 4 is not determined by the balance of the urging force (spring force) of the left and right springs 46, 47, but by the springs 46, 47. The springs 46, 47 are mechanically determined by urging the levers 41, 42 in opposite rotational directions to bring the intermediate parts 41b, 42b into contact with the bearing pipe 35 as a stopper.
The biasing force (spring force) of the springs does not affect each other, and even if there is some variation in the preload of the springs 46 and 47, the neutral point of the front frame 4 can always be accurately determined, and Adjustment of preload of 46 and 47 becomes easy. In addition, each spring 46,
The adjustment of the preload of 47 is performed by adjusting the mounting positions of the springs 46 and 47 on the brackets 48 and 49, advancing and retracting an unillustrated adjusting bolt screwed to the upper end portions 41a and 42a of the levers 41 and 42, and the like. Done by

In order to turn the three-wheeled bicycle 1 to the left, for example, when the occupant tilts the posture to the left while seating on the seat 3 and swings the front frame 4 to the left, FIG.
As shown in, the main pipe 1 that constitutes the front frame 4
4 swings to the left (counterclockwise in FIG. 7) about the swing shaft 36, and the left lever 41, which abuts against this, swings in the same direction (counterclockwise in FIG. 7) about the support shaft 43. Turn it. Then, the spring 46 on the right side, which urges the lever 41 on the left side, expands, whereby a restoring force for returning the front frame 4 to the neutral state acts on the lever 41 on the left side and the main pipe 14, so that the three-wheel bicycle When the vehicle 1 makes a left turn and goes straight, the front frame 4
Is restored to the neutral state shown in FIG. 6 by the restoring force. At this time, since the lever 42 on the right side is immovable and the intermediate portion 42b is kept in contact with the bearing pipe 35 as a stopper portion, no restoring force is generated in the spring 47 on the left side. do not do.

As shown in FIG. 4, a pair of left and right stoppers 51 are attached to the left and right of the cross pipe 33 (see FIG. 2) of the rear frame 6, and each stopper 51 is attached to the cross pipe 33. The support base 51a which is bound
When the front frame 4 is in a neutral state, both elastic bodies 51b are placed on the left and right sides of the main pipe 14 when the elastic body 51b made of rubber is fitted and screwed. It is located a predetermined distance away from this. As shown in FIG. 7, the front frame 4 of the three-wheeled bicycle 1 swings to the left until the main pipe 14 contacts the left stopper 51 (until the swing angle reaches the maximum value α). )Permissible.

Although not shown, in the case where the occupant tilts the posture to the right and swings the front frame 4 rightward because the three-wheeled bicycle 1 turns right, the main pipe forming the front frame 4 is rotated. 14 is to the right of the swing shaft 36 (see FIG.
The lever 4 on the right side that swings in the clockwise direction
2 is rotated about the support shaft 43 in the same direction (clockwise in FIG. 7). Then, the left spring 47 for urging the right lever 42 expands, whereby a restoring force for returning the front frame 4 to the neutral state acts on the right lever 42 and the main pipe 14, so that the three-wheel bicycle is operated. When the vehicle 1 makes a right turn and goes straight, the front frame 4 is returned to the neutral state shown in FIG. 6 by the restoring force. At this time, the lever 41 on the left side is immovable, and the intermediate portion 41b holds the bearing pipe 35 serving as the stopper portion, so that no restoring force is generated on the spring 46 on the right side.

When the front frame 4 of the three-wheeled bicycle 1 swings to the right, the main pipe 14 moves to the right side of the stopper 5.
1 is allowed (until the swing angle reaches the maximum value α).

As described above, in the swing restoring mechanism 10 according to the present invention, the left and right swings of the front frame 4 are restored by the left and right independent springs 46 and 47, respectively. Compared with a spring that generates a restoring force against the swing in both the left and right directions, the springs 46 and 47 are less susceptible to fatigue due to aging, and a stable restoring function can always be maintained.

Further, by disposing the support shaft 43, which is a shaft fulcrum of the pair of left and right levers 41, 42, below the swing shaft 36, the height of the main pipe 14, that is, the vehicle height is suppressed to be low, and the rear frame 6 is provided. The luggage carrier space secured above can be arranged at a low position, so that the luggage carrier space can be expanded.

Further, the front frame 4 is stopped by the stopper 51.
Since the left and right swing angles of the vehicle are restricted within a predetermined range (angle 2α), high stability of the vehicle body is ensured.

In the above description, the present invention is particularly applied to an auxiliary power type three-wheeled bicycle. However, the present invention is also applicable to an ordinary rocking type three-wheeled bicycle other than the auxiliary power type. Of course there is.

[0039]

As is apparent from the above description, claim 1
According to the invention described in 2, the left and right swings of the front frame are restored by the left and right independent springs, respectively, so that the springs are unlikely to suffer from fatigue due to aging, and always maintain a stable restoring function. You can Further, by disposing the pivotal fulcrum of the lever below the swing shaft, it is possible to suppress the vehicle height to a low level and to expand the load carrier space secured on the rear frame. Furthermore, the neutral point of the front frame is the biasing force (spring force) of the left and right springs.
It is not determined by the balance of the above, but it is determined by urging the pair of left and right levers in opposite rotational directions by springs so that the intermediate part of each lever abuts the stopper part on the rear frame side. The urging forces do not affect each other, and the neutral point of the front frame is mechanically accurately determined, and the spring preload can be easily adjusted.

Further, according to the third aspect of the invention, since the left and right swing angles of the front frame are restricted within a predetermined range by the stopper, it is possible to obtain an effect that a high stability of the vehicle body can be secured. To be

[Brief description of drawings]

FIG. 1 is a side view of a three-wheeled bicycle including a rocking and restoring mechanism according to the present invention.

FIG. 2 is a partial plan view showing a vehicle body frame structure of a rear portion of a three-wheeled bicycle including a swing restoring mechanism according to the present invention.

FIG. 3 is a partial side view showing a vehicle body frame structure of a rear portion of a three-wheeled bicycle including a swing restoring mechanism according to the present invention.

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

FIG. 5 is a perspective view of a swing restoring mechanism according to the present invention.

FIG. 6 is an explanatory view showing a neutral state of the swing restoring mechanism according to the present invention.

FIG. 7 is an explanatory view showing a swing state of the swing restoring mechanism according to the present invention.

FIG. 8 is a perspective view showing a configuration of a conventional swing restoring mechanism (torsion spring type).

FIG. 9 is a cross-sectional view showing a configuration of a conventional swing restoring mechanism (Nighthart mechanism).

[Explanation of symbols]

1 tricycle 2 front wheels 3 sheets 4 front frame 5 rear wheels 6 rear frame 10 Swing restoration mechanism 14 Main pipe 35 Bearing pipe (stopper part) 36 swing axis 41, 42 lever 41a, 42b Upper end of lever 41b, 42b Lower end of lever 43 Support shaft (Lever shaft support) 46, 47 springs 51 stopper

Claims (3)

(57) [Claims] 1. A rocking restoration for returning the front frame of a three-wheeled bicycle to a neutral state, in which a front frame supporting front wheels and a seat is configured to be rockable left and right with respect to a rear frame supporting two rear wheels. A mechanism, in which the front frame is centered in the vehicle width direction along the longitudinal direction of the vehicle body.
The main pie is constructed by including the arranged main pipe.
On either side of the front or rear frame
The fixed swing shaft is arranged and the front frame or the rear frame
Bearing pipe that pivotally supports the swing shaft at the center of the other vehicle width direction
By arranging the
As a core, it is swingably supported to the left and right with respect to the rear frame.
At the same time, in the shaft support provided vertically below the swing shaft.
Thus one end provided with a rotatably axially supported by a pair of levers to the rear frame, opposite to each other the two levers at the left and right spring interposed between the rear frame and the levers about its one end shaft support The bearing pipe is urged in the rotating direction to bring the other end of each lever into contact with the main pipe, and the intermediate portion of each lever is in contact with the stopper portion.
A rocking restoration mechanism for a three-wheeled bicycle, which is configured as follows . 2. A method of left side lever biased in the right spring, characterized by energizing the right lever on the left side of the spring at the upper end of the levers that sandwich the main pipe from both sides claimed A swing restoring mechanism for a three-wheeled bicycle according to item 1. 3. The swing restoring mechanism for a three-wheeled bicycle according to claim 1, wherein a stopper for restricting left and right swing of the front frame is provided on the rear frame.