JP2023114706A - Quadricycle - Google Patents

Abstract

To guarantee safety for fall protection, offer ease of pedaling, and stabilize a left and right balance and a forth and back balance.SOLUTION: A power-assisted quadricycle 1 includes two front wheels 42, two rear wheels 52, cranks 64a and 64b that transmit power to the rear wheels 52 and rotate about crank shafts, a seat 71 on which a driver is seated, and a hip support member 72 that supports the hip of the driver who is seated on the seat 71. A fore-and-aft direction distance L from the center of the crank shaft to the rearmost end of the seat is larger than a vertical direction distance H orthogonal to the fore-and-aft direction from the center of the crank shaft to a seat uppermost end.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an electrically assisted four-wheeled bicycle that can be safely and safely driven by elderly people.

Conventionally, there are three-wheeled bicycles as bicycles for the elderly. More specifically, bicycles with one front wheel and two rear wheels (one front wheel and two rear wheels) (see, for example, Patent Document 1), There is also a type with two front wheels and one rear wheel (two front wheels and one rear wheel).

JP-A-9-263289

Generally, in an electric three-wheeled bicycle, from the viewpoint of safety to prevent overturning when used by elderly people, etc., it is preferable that the position of the seat be as low as possible so that the rider's legs touch the ground. However, in this case, the distance between the pedals and the seat in the height direction becomes small, and the legs do not extend when the pedals are rotated, making it difficult to pedal.

Therefore, for example, regarding the positional relationship between the pedals and the seat, it is conceivable to increase the distance from the pedals to the seat in the front-rear direction and shorten the distance from the pedals to the seat in the vertical direction, thereby making it easier to pedal.

However, in this case, there is a large distance between the position of the driver's body and the steering wheel.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a four-wheeled bicycle capable of ensuring safety against overturning, realizing ease of pedaling, and stabilizing the left-right, front-rear balance.

In order to achieve the above object, the four-wheeled bicycle of the present invention includes two front wheels, two rear wheels, a crank that rotates around the crankshaft for transmitting power to the rear wheels, and a driver's seat. A seat and a waist support member for supporting the waist of the driver seated on the seat, wherein a distance L from the center of the crankshaft to the rearmost end of the seat is a distance L from the center of the crankshaft to the top end of the seat. is larger than the vertical distance H perpendicular to the longitudinal direction.

By setting H>L, even if the seat position is lowered so that the driver's legs touch the ground, the distance between the pedals and the seat in the height direction will not be too close to make pedaling difficult. However, at that time, the distance between the position of the user's body and the steering wheel is large due to the above, so the left-right front-rear balance becomes unstable. Therefore, in the present invention, a four-wheeled bicycle is used instead of a three-wheeled bicycle, and by providing a waist support member behind the seat, the above problem is solved, the left-right and front-back balance is stabilized, and pedaling can be stably performed. .
Therefore, the four-wheeled bicycle of the present invention can prevent overturning when used by the elderly, eliminate the difficulty of pedaling and facilitate pedaling, and stabilize the left-right and front-back balance when riding or running. Therefore, you can drive safely.

According to the present invention, it is possible to realize all of the safety of preventing overturning, the ease of rowing, and the stabilization of balance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view of the electric assist three-wheeled bicycle which shows embodiment of this invention. It is a perspective view of the frame structure in the same embodiment. It is a perspective view of the front-wheel rocking mechanism in the same embodiment. It is an enlarged view of the battery attachment part in the same embodiment. It is an enlarged view of the waist support part in the same embodiment. It is an enlarged view of the drive part in the same embodiment. It is an enlarged view of a differential gear part in the same embodiment.

An embodiment of the present invention will be described below with reference to the drawings. In particular, the present embodiment provides a tilt of the frame similar to that of a conventional two-wheeled bicycle when turning, and facilitates pedaling when starting at a low speed for elderly people who find it difficult to ride a conventional two-wheeled bicycle. It is a four-wheeled bicycle that can

In this embodiment, an example in which the four-wheeled bicycle according to the present invention is a four-wheeled bicycle with an electric power assist is used, but the present invention can also be applied to a four-wheeled bicycle without an electric power assist.

In the following description, the left-right direction in FIGS. 1 and 2 is defined as the front-rear direction (horizontal direction), the up-down direction is defined as the up-down direction, the front is defined as the right, and the back is defined as the left.

<Overall composition>
The electrically assisted four-wheeled bicycle 1 (four-wheeled bicycle 1) includes a body frame 2, a front frame 3, a rear frame 4, two front wheels 42, two rear wheels 52, a handlebar 11, a seat 71, mainly have

The front frame 3 has a front upper stay 22 and a front lower stay 23 .

The front upper stay 22 has a suspension bracket 31 at its front lower end. The suspension bracket 31 connects the swing arm 41 at the center in the left-right direction so that the swing arm 41 can swing left and right. The swing arm 41 rotatably supports a pair of left and right front wheels 42 via a pair of left and right knuckle arms 61a and 61b. The swing arm 41 slidably supports a pair of left and right dampers 43 (springs). That is, dampers 43 are arranged on the left and right sides of the swing arm 41 in order to connect the suspension bracket 31 of the front frame 3 and the swing arm 41 so that the swing arm 41 can be tilted left and right.

The suspension bracket 31 supports the bearing 13 at a laterally central position, and the bearing 13 rotatably supports the steering shaft 12 . The steering shaft 12 is also supported by an upper handle bracket 33 and a lower handle bracket 34 provided on the front upper stay 22 . The steering shaft 12 has a handle 11 on its top. The handle 11 has brake levers 56a and 56b.

The steering shaft 12 is slidably supported by knuckle arms 61a and 61b via tie rods 62. As shown in FIG. As a result, the operation of the steering wheel 11 is transmitted to the front wheels 42 and the steering shaft 12 steers the front wheels 42 .

The brake levers 56 a and 56 b transmit the input brake operation to the front brake device 44 and the rear brake device 45 . The front brake device 44 is attached to the knuckle arm 61b. The rear brake device 45 is attached to the axle housing 93 (Fig. 7).

A lock 78 for locking the electrically assisted four-wheeled bicycle 1 is attached to a predetermined position of the steering shaft 12 .

The front upper stay 22 has a front carrier 75 . The front carrier 75 attaches the front basket 76 and the headlight 83 to the front upper stay 22 . In particular, the front carrier 75 (front frame 3 ) supports the front basket 76 so that it is positioned above the center of rotation of the front wheel 42 .

The front upper stay 22 has a battery stay 32 that supports the base battery 81a. The battery 81 drives the motor 21 that powers the electrically assisted four-wheeled bicycle 1 . That is, the battery 81 is a drive battery that drives the rear wheels 52 via the cranks 64a and 64b. The battery 81 is removable from the base battery 81a. Thus, when the electrically assisted four-wheeled bicycle 1 is driven by the motor 21 , it is arranged between the steering shaft 12 and the crankshaft 65 and attached to the front upper stay 22 .

The body frame 2 has a motor bracket 24 , a seat tube 25 , a seat bracket 35 and a rear pivot 36 .

The motor bracket 24 attaches the motor 21 to the body frame 2 via bolts. The motor 21 is connected to cranks 64a and 64b via a crankshaft 65 to rotate the cranks 64a and 64b. The motor 21 has a control function (not shown) that prevents the driving force of the rear wheels 52 from exceeding a set value.

Cranks 64 a and 64 b rotate around crankshaft 65 and transmit power to rear wheels 52 . Cranks 64a, 64b have pedals 63a, 63b at their distal ends. The pedals 63a, 63b transmit torque from the driver to the cranks 64a, 64b. Cranks 64 a and 64 b are connected to front sprocket 54 .

The seat tube 25 has a front end substantially in the same vertical position as the cranks 64a, 64b connected to the motor bracket 24, and a rear end extending rearward and upward from the front end. The seat tube 25 (vehicle frame 2 ) has a horizontal portion 25 a extending parallel to the front-rear direction between the crankshaft 65 and the seat 71 . The horizontal portion 25a is a portion of constant length extending from the front end to the rear end.

A seat bracket 35 is attached to the rear end of the seat tube 25 . The seat bracket 35 attaches a seat (saddle) 71 for seating a driver and a waist support member 72 to the seat tube 25 via a seat frame 73 . The seat frame 73 is fixed to the seat bracket 35 with a bolt or the like through an elongated hole having a longitudinal direction in the front-rear direction. The seat frame 73 is fixed to the seat bracket 35 at desired positions of the long holes, so that the positions of the seat 71 and the waist support member 72 can be adjusted forward and backward with respect to the seat bracket 35 .

Here, in the electrically assisted four-wheeled bicycle 1 according to this embodiment, as shown in FIG. The seat 71, the vehicle body frame 2, and the like are configured to be larger than the vertical distance H perpendicular to the front-rear direction.

A rear pivot 36 connects the rear frame 4 to the body frame 2 .

The rear frame 4 supports rear wheels 52 and rear sprockets 53 . The rear sprocket 53 is interlocked with the hub of the rear wheel 52 .

Chains 55 a and 55 b are stretched between the front sprocket 54 and the rear sprocket 53 . The chains 55 a and 55 b are connected by a counter sprocket 92 . The chains 55a, 55b also have required chain tensioners 91a, 91b. Chains 55 a and 55 b transmit torque input from the driver via pedals 63 a and 63 b and torque input from motor 21 to rear wheel 52 via rear sprocket 53 .

The rear wheels 52 are supported by the rear frame 4 via axle shafts 94 . Axle shaft 94 is housed in axle housing 93 . A differential gear 95 is attached to an intermediate portion of the left and right axle shafts 94 .

<Effects of this embodiment>
The present embodiment configured as described above has the following effects.
1, the distance L from the center of the crankshaft 65 to the rearmost end of the seat 71 is greater than the distance H from the center of the crankshaft 65 to the top end of the seat 71 in the vertical direction. configured to grow.

As a result, even if the seat 71 is lowered so that the rider can sit with his legs on the ground, the distance between the pedals 63a, 63b and the seat 71 is too close to make it difficult to pedal.

Further, if the distance L in the front-rear direction is greater than the distance in the vertical direction H as described above, the distance between the driver and the steering wheel 11 may be large depending on the body type of the driver, and the left-right front-rear balance may become unstable if left as it is. It may get lost. Therefore, in the present embodiment, the four-wheeled bicycle 1 having four wheels instead of a three-wheeled bicycle is configured, and the waist support member 72 is provided to solve the above problem, stabilize the left-right front-rear balance, and provide stable pedaling. can do.
Therefore, the four-wheeled bicycle 1 of the present invention can prevent overturning when used by the elderly, eliminate the difficulty of pedaling to facilitate pedaling, and stabilize the left-right front-rear balance when riding or running. You can drive safely and securely.

In addition, particularly in this embodiment, the front frame 3 and the swing arm 41 are connected to the left and right sides of the swing arm 41 so as to be tiltable to the left and right. This allows the entire vehicle body to be neutral when stationary. For this reason, the electrically assisted four-wheeled bicycle 1 does not require a stand hanging operation for fixing the electrically assisted four-wheeled bicycle 1 . This allows elderly people to comfortably handle the electric assist four-wheeled bicycle 1 .

Further, particularly in this embodiment, the position of the seat 71 in the front-rear direction is made adjustable. Thereby, it is possible to provide the position of the seat 71 that matches the body shape of the driver.

In addition, in this embodiment, the battery 81 is arranged between the steering shaft 12 and the crankshaft 65, so that the center of gravity of the vehicle body is positioned forward, thereby improving stability during riding. As a result, even elderly people can drive the electric assist four-wheeled bicycle 1 safely and securely.

In addition, particularly in this embodiment, since the front basket 76 is provided above the rotation centers of the two front wheels 42, the running stability is further improved when the vehicle is loaded. As a result, even elderly people can drive safely and securely.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist and technical idea of the present invention.

In addition, in the above description, descriptions such as "the same", "equal", and "different" regarding external dimensions and sizes are not strictly defined. In other words, "same", "equal", and "different" mean "substantially the same", "substantially equal", and "substantially different", with design and manufacturing tolerances and errors allowed. .

In addition to the methods already described above, the methods according to the above-described embodiments and modifications may be appropriately combined and used.

In addition, although not exemplified one by one, the present invention can be implemented with various modifications within the scope of the invention.

1 Electric power-assisted four-wheeled bicycle 2 Body frame 3 Front frame 4 Rear frame 12 Steering shaft 25a Horizontal portion 41 Swing arm 42 Front wheel 52 Rear wheel 64a, 64b Crank 65 Crankshaft 71 Seat 72 Lumbar support member 76 Front basket 81 Battery H Up and down Directional distance L Forward/backward distance

Claims (6)

two front wheels and
two rear wheels and
a crank rotating about a crankshaft that transmits power to the rear wheel;
a seat for the driver, and
a waist support member that supports the waist of the driver seated on the seat,
A longitudinal distance L from the center of the crankshaft to the rearmost end of the seat is greater than a distance H in a vertical direction orthogonal to the longitudinal direction from the center of the crankshaft to the topmost end of the seat,
A four-wheeled bicycle characterized by: In the four-wheeled bicycle according to claim 1,
a swing arm that rotatably supports the front wheel;
A four-wheeled bicycle, further comprising: a front frame that connects the swing arm so as to be left-right tiltable at a center of the four-wheeled bicycle in a left-right direction perpendicular to the front-rear direction and the up-down direction. In the four-wheeled bicycle according to claim 1 or claim 2,
A four-wheeled bicycle, wherein the seat is adjustable in position in the front-rear direction. In the four-wheeled bicycle according to any one of claims 1 to 3,
a steering shaft for steering the front wheels;
A four-wheeled bicycle, further comprising: a drive battery arranged between the steering shaft and the crankshaft for driving the rear wheel via the crank. In the four-wheeled bicycle according to any one of claims 1 to 4,
A four-wheeled bicycle, further comprising a vehicle body frame that supports the seat and has a horizontal portion that extends parallel to the front-rear direction between the crankshaft and the seat. In the four-wheeled bicycle according to any one of claims 1 to 5,
front basket and
A four-wheeled bicycle, further comprising: a front frame supporting the front basket above the center of rotation of the front wheel.