JPS616087A - Steering front one-wheel power transmission gear for motor tricycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a power transmission device to one steering wheel of a front- and rear-wheel drive type automatic tricycle.

One front steering wheel and two rear steering wheels are arranged at the front end of the body frame, and balloon tires (ultra low pressure tires) are attached to each of the front and rear wheels, and these are connected to a power unit mounted on the body frame and a power transmission device. We have already proposed a so-called automatic three-wheeled vehicle for traveling on rough terrain (automatic three-wheeled buggy vehicle), in which the front and rear wheels are connected together to drive the front and rear wheels simultaneously.

This type of tricycle has a body frame 90 as shown in FIG.
A toothed belt 95 is suspended and connected between the output shaft 92 of the power unit 91 mounted in the vehicle, the transfer device 94 disposed below the roadside non-frame 93 of the output shaft 92, and the two rear wheels Wr+ and Wr2. The above body frame 9
A motive power system consisting of a telescoping shaft drive mechanism 99 equipped with constant velocity ball joints 97 and 98 at both ends is connected to a front wheel drive device 96 on a front fork 89, which is a mounting device pivotally supported at the front end of the motor vehicle. A transmission means was interposed, and the front wheel drive device 96 and the single steering front wheel Wf' were connected by a toothed belt 88.

Therefore, the single steering wheel W f ' is driven by the vertical movement of the front fork 89, more specifically, by the vertical movement of the bottom case 89' of the front fork, the shaft drive mechanism 99 rotates around the constant velocity ball joint 97 on the vehicle body side. Since it swings up and down, the inertial weight during swinging is large, and therefore the inertial force is large.

Furthermore, since the interaxial distance L between the constant velocity ball joint 97, which is the center of swing, and the front wheel drive device 96 of the front fork 89 becomes long, the moment of inertia around the constant velocity ball joint 97 becomes large.

This tends to cause vibrations due to an increase in the load applied to the front fork 89, and also causes adverse effects such as a decrease in damping response and an increase in steering moment, which adversely affects the front fork 89's functionality.

Furthermore, due to the increase in the buffer stroke, the upper swing space of the shaft drive mechanism located between the upper part of the power unit and the fuel tank is increased, which makes it easier to interfere with other auxiliary equipment and increases the installation space. This is inconvenient for tricycles, motorcycles, etc., which have large restrictions. Moreover, it is unfavorable in terms of external design when viewed from the side.

The present invention has been made in view of the problems in the power transmission device of the shaft drive mechanism to one wheel in front of the steering wheel of a three-wheeled motor vehicle or a two-wheeled motor vehicle, etc., and has been made to effectively solve the problem.
The purpose of this is to rotatably arrange a part of the drive shaft mechanism between the transfer device on the body frame side and the front wheel drive device on the front fork side inside the frame member that makes up the body frame. At the same time, a short telescopic shaft drive mechanism is connected between the front end of the frame member and the front wheel drive device with joint members such as constant velocity ball joints on both ends, and the front fork is steered left and right with respect to the vehicle body frame. However, it is configured to enable torque transmission, thereby reducing the inertial weight and moment of inertia associated with the vertical movement of the shaft drive mechanism applied to the front fork, thereby improving the response of the front fork and reducing vibration etc. Accordingly, it is an object of the present invention to provide a power transmission device for one wheel in front of a steering wheel of a tricycle, etc., which is designed to improve riding comfort.

A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

Fig. 1 is a side view of a three-wheeled motor vehicle for traveling on rough terrain equipped with a power transmission device to one wheel in front of steering according to the present invention, Fig. 2 is a plan sectional view taken along line C1 to C2 of the main part, and Fig. 3 is C3~ in Figure 2
04 line, FIG. 4 is a front view thereof, and FIG. 5 is a rear view thereof. In this embodiment, a three-wheeled motor vehicle is shown, but it can also be applied to a two-wheeled motor vehicle.

As shown in Fig. 1, the vehicle body frame F includes a main frame 2 with a rectangular cross section extending rearward and downward from the upper part of the head pipe 1, a down tube 3 extending downward from the lower part of the head pipe 1, and this down tube 3. Two bottom frames 4 and 5 are fixed to both sides of the frame and are bent while extending downward. Left and right parallel center frames 6 and 7 which are inclined and whose upper ends are fixed near the rear side of the main frame 2; and a rear frame 8°9 which extends left and right parallel to the rear from the main frame 2;
．． A rear down frame 10 which connects the rear part of the frame 9 and the lower part of the center frames 6 and 7, respectively; and a hollow cylindrical sub-frame 12 which further connects the lower part of the down tube 3 and the rear lower part of the main frame 2. It consists of To explain this subframe 12 in detail, the front end is formed into an angular cross section as shown in FIG. are supported by stays 13, and these are fixed together by welding or the like.

FIG. 5 shows the state of connection at the rear of the sub-frame 12. Between the left and right center frames 6 and 7, a cross member 14 whose central portion is bent upward in an arc shape is installed and connected. has two flanges 15 and 16
The flanges 17 and 18 protruding from the subframe 12 are brought into contact with the flanges 17 and 18 to be integrally connected.

There are also two locations 7 on the rear lower surface of main frame 2.
Lunges 19 ′, 20 are provided to protrude downward, and a bunker member 2 provided on the upper surface of the subframe 12
3 and 24, respectively.

The sub-frame 12 is constructed as a reinforcing member located below the non-frame 2 at approximately the center of the vehicle body frame F in the longitudinal direction.

FIG. 2 is a plan cross-sectional view taken along line C+-C2 in FIG. 1, showing a power transmission path to the single steering wheel Wf disposed within the subframe 12.

That is, bearings 25 are fitted to the front and rear ends of the sub-frame 12, respectively, and a drive shaft 26 is rotatably supported through the bearings, passing through the inside as shown in FIG. , spline shafts 27 are carved on both ends.

The rear end is formed into an angular cross section as shown in the figure, and a transfer device 28 is provided thereon, and the transverse shaft 2
9 is rotatable via a bearing 30, and connected to the drive shaft 26 is a pair of bevel gears G1 with a spline connection of 1μ.
and 02 are meshed and connected, and the driving toothed boob IJ-32 of the output shaft 31 on the power unit P side, the driven toothed boob IJ-33 fixed to the horizontal shaft 29, and the two rear wheels Wr+, W
A toothed belt 34 given appropriate tension by a tensioner mechanism 63 is suspended around a driven toothed pulley 62 on a driven shaft 35 that supports r2, thereby transmitting power. (It is possible to drive three wheels simultaneously, one front wheel and two rear wheels.

That is, the front fork Ff adopts a telescoping system as shown in Figs. A pair of left and right fork pipes 39 and 40 are provided, and a pair of bottom cases 41 and 42 are fitted into the lower sides of the fork pipes 39 and 40 so as to be extendable and slidable in the axial direction. A base 4344 protruding from the front steering wheel Wf is connected to the base 4344 by a stabilizer 46 equipped with a front wheel drive device 45 serving as a torque transmission device for the power unit (P).

That is, the stabilizer 46 is provided with a lateral drive shaft 49 by a bearing 48 in the direction of the axle 47 that supports the front wheel Wf.
is supported, and a vertical drive shaft 50 is rotatably supported in the longitudinal direction of the vehicle body frame F so as to form orthogonal coordinates with the lateral drive shaft 49. Arranged to allow torque transmission. A drive toothed pulley 51 is fixed to the outside of the lateral drive shaft 49, and a driven toothed pulley 52 is fixed to the front steering wheel Wf, on which a toothed belt 53 is suspended.

Further, the rear end of the vertical drive shaft 50 is a spline shaft 54, to which a constant velocity ball joint 55 is spline-coupled, and the front end of the drive shaft 26 is a spline shaft 54 that moves forward and backward in the axial direction and transmits torque. A so-called tripod type constant velocity ball joint 56 that can perform
The constant velocity ball joints 55 and 56 are connected by a front drive shaft 57.

The vertical and horizontal bending centers of the constant velocity ball joint 55 are made to approximately coincide with the center of rotation of the steering shaft 36 as shown in FIG. , the drive shaft 26 is approximately on the center line in the longitudinal direction in the plane of the vehicle body frame F, and on the side, connects the rear side of the non-frame 2 and the upper side of the bottom case 4142, and is located between the main frame 2 and the power unit P. It will be arranged.

Incidentally, instead of the toothed belts 34 and 53, the power transmission means of this part may be a shaft drive mechanism, or a transmission member such as another belt, chino, etc. may be used. In the figure, the constant velocity ball joint 55 is shown as a separate structure using a spline connection, but it is obvious that a structure in which the shaft portion and the joint portion are integrally formed may be used, and of course, other types of joint members may also be used. .

The front wheel Wf and the front wheel drive device 45 are controlled by the fork pipe 39, 40 and the bottom case 41 according to the road surface undulations.
．． 42 mutually extend and contract, a buffering effect is achieved and external vibrations are absorbed. No front fork Ff
When the front drive shaft 57 moves up and down, the constant velocity ball joint 56 on the vehicle body side bends and follows it while absorbing the expansion/contraction displacement in the axial direction, so torque can be transmitted without any problem. The distance between the fast ball joint 56 and the front wheel drive device 45 is the same as in Figure 6,
Since it is shorter than 2, it can be made lighter by this weight difference, thereby suppressing the inertia force generated during vertical swing, reducing the load on the front fork Ff, and improving riding comfort. can.

In addition, when the front fork Ff is turned left or right, the bending center of the constant-velocity ball joint 55 is made substantially the same as the steering axis 36, so that it can be freely followed and the torque can be transmitted smoothly and quietly. Ru. Furthermore, by having the configuration as explained above, the center of swing is located at the subframe 1.
Since the constant velocity ball joint 56 is used at the front end of the power unit P, the upper part of the power unit P, especially the upper part of the cylinder head 58, is the same as that of a conventional tricycle without a front wheel drive device. The degree of freedom in mounting can be increased, and the side appearance design can be made to be comfortable and desirable. Of course, since the drive shaft 26 is housed within the sub-frame 12, there is no danger to the outside, which improves running safety, and furthermore, it does not cause damage to other components due to getting involved or coming into contact with them. etc., and since it is possible to prevent the infiltration of yellow dust, etc., it is advantageous for long-term durability and can be maintenance-free.

Next, a modified embodiment of the present invention will be described based on FIG.

In this modified embodiment, the constant velocity ball joint 56' on the side of the vehicle body frame F has only a bending action, like the constant velocity ball joint 55 on the front fork Ff side, and the front drive due to the expansion and contraction buffer vertical movement. shaft 57
A front shaft drive mechanism of spline type 60 is provided, which absorbs the axial expansion and contraction displacement of ' by spline fitting.

As is clear from the above description, according to the present invention, the main part of the shaft drive mechanism, which is a power transmission member to one front steering wheel, is arranged inside the structural members of the vehicle body frame disposed in the longitudinal direction, and The front shaft drive mechanism that swings vertically and the front shaft drive mechanism are connected to the front fork, reducing the load on the front fork to less than 1/3 compared to the conventional method. Since the inertial weight and radius of inertia associated with the vertical movement of the power unit can be set small, the inertial force and moment of inertia can be suppressed, thereby improving ride comfort. It has features such as creating an effective space between the parts, increasing the degree of freedom in installing auxiliary equipment, preventing interference with them, and providing an excellent external design on the side. It is ideal as a power transmission device to the front wheel of a tricycle, motorcycle, etc.

4 Detailed Description of the Invention Fig. 1 is a side view of a three-wheeled motor vehicle for traveling on rough terrain equipped with a power transmission device to one wheel in front of steering according to the present invention, and Fig. 2 is a plane cross-section of the same main part taken along line 01-02. Figure 3 is from C3 in Figure 2.
04 line sectional view, Figure 4 is the same front view, Figure 5 is the same rear view,
FIG. 6 is a side view showing the structure of a tricycle equipped with a conventional power transmission device, and FIG. 7 is a side sectional view of a power transmission device according to another embodiment.

In addition, in the drawing, 1 is a head pipe, 3 is a down tube, and 6 is a head pipe.
and 7 are center frame, 12 is subframe, 26 is tribunyaft, 39 and 40 are fork pipes, 41
and 42 are the bottom case, 45 is the front wheel drive device, 46 is the stabilizer, 55 and 56 are constant velocity ball joints, 5
7 is a front drive shaft.

Claims (1)

[Scope of Claims] 1) A power transmission device in which a power unit is mounted on a vehicle body frame, and one front wheel on a steering device side that is pivotally supported in front of the vehicle body frame is connected to the power unit via a shaft drive mechanism, The shaft drive mechanism for the front single wheel drive is disposed inside the vehicle body frame member arranged in the longitudinal direction, and both ends are provided between the front end of the shaft drive mechanism and the front wheel drive device on the steering device side. A single-wheel power transmission device before steering for a tricycle, characterized in that a front shaft drive mechanism equipped with a constant velocity ball joint is interposed in the front shaft drive mechanism. 2) The front steering wheel of a tricycle according to claim 1, wherein the front shaft drive mechanism is connected to a constant velocity ball joint capable of transmitting torque while moving in the axial direction toward the vehicle body. Power transmission device. 3) The single-wheel power transmission device before steering of a tricycle according to claim 1, wherein the front drive shaft mechanism has a telescopic structure using a spline system with constant-velocity ball joints at both ends. 4) The drive shaft mechanism and the front drive shaft mechanism are rotatably connected and are located substantially at the center in the longitudinal direction in the plane of the vehicle body frame, and are disposed between the main frame and the power unit on the side. The single-wheel power transmission device before steering for a tricycle according to item 1.