JPS6112458A - Vehicle brake device having two rear wheels - Google Patents

Abstract

PURPOSE:To enhance the maintainability of a vehicle brake device, by forming a cover for covering the periphery of a member to be braked in a rear wheel brake, with a pair of halved members which are axially splitable from each other, and by coupling at least one of the halved member to the stationary side through an axially extendable pipe. CONSTITUTION:In an arrangement in which the output power of an engine is transmitted to a rear axle 17 through an output shaft 23, bevel gears 24, 25, a drive shaft 19 and a final speed change gear unit 25, a rear shaft part 21 in the drive shaft 19, which is coupled with a front shaft part 20 by means of a universal joint 22 is provided thereon with a hydraulic disc brake 28 for braking rear wheels. The periphery of a disc rotor 29 in this disc brake 28, which is splinedly coupled with the rear shaft 21, is surrounded by a cover 30 composed of a pair of longitudinally splitable cover halved members 31a, 31b which are made abutted against each other in the axial direction of the rear shaft 21. Further, one 31b of the halved members is attached to a mission casing 12 through a tubular rubber boot 42, thereby it is possible to facilitate the exposure of the disc rotor, a caliper, etc.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a four-wheeled motor vehicle or a three-wheeled motor vehicle in which engine power is transmitted to two left and right rear wheels via a drive shaft extending in the longitudinal direction of the vehicle body. The present invention relates to a brake device for such a vehicle, and particularly to a brake device for one rear wheel.

(Technical background of the invention and its problems) In this type of vehicle for traveling on rough terrain, the brake for the rear wheels has conventionally been generally installed on the rear axle that supports the two left and right rear wheels. Recently, the present applicant has attempted to provide a drive shaft for transmitting engine power to the rear axle, and has already filed a patent application as Japanese Patent Application No. 59-18416.

By the way, when a brake is provided on the drive shaft as shown in the above-mentioned prior art, the projected area from the front and rear directions is larger than when it is provided on the rear axle, and the brake is more likely to be hit by obstacles on the road surface while driving. In this case, it is necessary to cover the area around the brake to protect it from obstacles, flying stones, etc.

However, if the area around the brake is simply covered with a cover, the cover must be removed from the drive shaft to expose the entire brake every time, for example, the pads are inspected or replaced, reducing maintainability. There were still issues such as:

[Purpose of the invention]

The present invention was made based on these circumstances,
To provide a brake device for a vehicle having two rear wheels that improves maintainability without the need to disassemble the entire cover or remove it from the drive shaft during maintenance and inspection of the brake.

[Summary of the invention]

That is, in order to achieve the above object, the present invention provides a braked member of a rear wheel brake on the drive shaft that transmits engine power to the rear axle, covers at least the periphery of the braked member of this brake with a cover, and The cover is constructed by a pair of cover halves that are separably abutted in the axial direction of the drive shaft, and at least one of the cover halves is provided with a telescoping tube that is freely expandable and retractable in the axial direction of the drive shaft. It is characterized in that it is connected to a case or an engine that supports the rear axle via the rear axle.

[Embodiments of the Invention] A first embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Reference numeral 1 in FIG. 1 is a frame that constitutes the vehicle body, and a support pipe 3 located at the front end of the main pipe 2 has a front axle 4.
is supported. Left and right front wheels 5 are located at both ends of the front axle 4.
．． 5 is supported so as to be steerable, and left and right underpipes 6.6 are led out rearward from this front axle 4, and the rear ends of these underpipes 6.6 are raised up. It is connected to the rear end of the main pipe 2. In addition, from the rear end of the main pipe 2, the left and right seat rails 1
, 1 are led out, and a back pipe 8 is connected between the rear end of the seat rail 7.7 and the rear end of the underpipes 6, 6.
, 8 have been constructed.

Between the main pipe 2 and the under pipes 6, 6,
An engine 9 is mounted, and above the engine 9 there are a fuel tank 10 and a sea 1-11 of 1ffl in the front and rear.
In addition, footrests 13 and 13 are installed on both left and right sides of the transmission case 12 of the engine 9.

On the other hand, left and right support cases 14.15 are fixed to the back pipe 8.8, respectively.
The final reduction gear case 1B is supported between 4 and 15.

And the support case 14.15 and the final gear case 1
8 includes a rear axle 17 that supports left and right rear wheels 16.
is rotatably supported, and this final reduction gear case 18
A drive shaft 19 that transmits engine power to the rear axle 17 is installed between the front end opening of the transmission case 12 and a power outlet 12 a provided at the center of the rear surface of the transmission case 12 . The drive shaft 19 of this embodiment is formed by connecting a front shaft 20 and a rear shaft 21 with a universal joint 22, and extends in the longitudinal direction approximately on the center line of the vehicle body. The front end of the front shaft 20 is connected to the output shaft 23 of the engine power inside the Mizramin case 12 via bevel gears 24 and 25, and
The rear end of the rear shaft 21 is housed in the final reduction gear case 18! 125, that is, it is connected to the rear axle 17 via a pinion 26 and a ring gear 27, which are always in mesh with each other.

The front wheels 5, 5 and the rear wheel 16.1B are both equipped with ultra-low pressure wide balloon tires.

Incidentally, a hydraulic disc brake 28 for braking the rear wheels is provided on the rear axle 21. That is, the reference numeral 29 is a braked member to which a braking force is applied, that is, in the case of this embodiment, a disk-shaped disc rotor. , fixed so that it can slide only in the axial direction. The circumference of the disc rotor 29 is covered with a metal cover 30, and this cover 30 has a front and rear bipartite structure formed by a pair of cover halves 31a and 31b abutting against each other in the axial direction of the rear wheel 21. is doing. That is, one cover half body 31a consists of a substantially disc-shaped flange wall integrally provided at the front end opening edge of the final reduction gear case 1B, and covers the rear surface side of the disc rotor 29. Further, the other cover half body 31b has a substantially dish-like shape, and its outer peripheral edge abuts against the front surface of the one cover half body 31a, and at multiple points along the circumferential direction of this abutting portion. Insert bolt 32... and insert bolt 1
-33..., it is removably fixed to one cover half body 31a. and,
A caliper 34 is bolted to the upper part of one cover half 31a, and this caliper 34 enters into the cover 30 through an opening 44 formed in the cover half 31a. Therefore, the cover 30 of this embodiment
integrally covers not only the disc rotor 29 but also the caliper 34. The caliper 34 holds a pair of pads 35a and 35b that press the disc rotor 29, and a cylinder chamber 36 in the caliper 34 has a piston 37 that presses one pad 35a.
are slidably fitted together, and this cylinder chamber 36 is connected through a brake hose 38 to a mask cylinder 40 actuated by a brake pedal 39. Therefore, when the brake pedal 39 is depressed, the hydraulic pressure generated in the mask cylinder 40 is applied to the cylinder chamber 36, and the piston 37 advances toward the disc rotor 29, causing the pad 35
a to the disc rotor 29, and the disc rotor 29 moves in the axial direction due to this compression, and is also pressed to the pad 35b on the opposite side, and both pads 35a
, 35b It is now being squeezed as a punishment.

In addition, a through hole 41 through which the rear shaft 21 passes is formed in the center of the front surface of the other cover half body 31b.
The opening diameter of the through hole 41 is larger than the outer diameter of the universal joint 22. Such a through hole 41 and the power outlet 1 of the mission case 12
A tubular rubber boot 42 that is extendable and retractable in the axial direction of the drive shaft 19 is installed between the drive shaft 19 and the drive shaft 19, and is tightened by a band 43.
The tightening is fixed by 43, and this rubber boot 4
2 substantially coaxially covers the connecting portion between the front shaft 20 and the rear shaft 21.

According to such a configuration, the cover 30 that covers the disc rotor 29 and the caliper 34 is divided into front and rear parts along the axial direction of the drive shaft 19, and one of the cover halves 31a is integrated with the final reduction gear case 18. Since the other cover half 31b is connected to the transmission case 12 via the rubber boot 42, for example, the pad 35a,
When replacing or inspecting 35b,
First, loosen the nuts 33... and remove the cover half body 31a,
31b are separated from each other and the other cover half body 31b located on the front side is shifted forward, the rubber boot 42 is shrunk and the disc rotor 29 and caliper 34 can be exposed to the outside. As a result, there is no need to disassemble the entire cover 30 or remove it from the drive shaft 19 every time maintenance and inspection work is performed, so that maintainability is improved.

Note that the present invention is not limited to the first embodiment described above, and FIG. 4 shows a second embodiment of the present invention.

In this second embodiment, a drum brake 51 is mounted on the drive shaft 19.
A drum 52 as a braked member is spline-engaged with the rear shaft 21. Further, a brake shoe plate 53 that covers the opening of the drum 52 is integrally formed at the front end opening of the final reduction gear case 18 . The brake shoe 55 is extended by a brake cam 56, and the brake cam 56 is connected to the brake pedal 39 via a lever 57 and a brake wire (not shown). Note that reference numeral 58 is a spring for returning the brake shoe.

A cover 59 that covers the periphery of such a drum brake 51
is constructed by a pair of cover halves 60a and 60b facing each other front and back, and the rear cover halves 60a are also used as the brake shoe plates 1 and 53.

Therefore, in the second embodiment as well, the drum 52 can be exposed by simply shifting the front cover half 60a forward with the nut 33811, and the brake can be removed in the same way as in the first embodiment. Maintenance and inspection work can be easily performed.

In carrying out the present invention, the heat dissipation of the brake may be improved by providing ventilation holes or cooling fins in the cover.

Further, in each of the above embodiments, the front cover half is movable, but on the contrary, the rear cover half may be connected to the final reduction gear case via a telescopic tube. In some cases, the front cover half is connected to the transmission case, and the rear cover half is connected to the final reduction gear case through telescopic tubes, and both cover halves can be moved. good.

Further, the vehicle according to the present invention is not limited to a four-wheeled motor vehicle, but may be a tricycle with one front wheel.

〔Effect of the invention〕

According to the present invention described in detail above, by simply shifting the cover half body in the axial direction of the drive shaft, at least the braked member of the brake can be exposed to the outside. Since there is no need to disassemble the entire cover or remove it from the drive shaft, there is an advantage that maintainability is improved.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention.
The figure is a side view of a four-wheeled motor vehicle, and the second figure is a plan view of the same.
FIG. 3 is a cross-sectional view of the power transmission line, and FIG. 4 is the second embodiment of the present invention.
It is a sectional view showing an example. 1...Vehicle body (frame), 9...Engine, 12.
...Mission case, 16...Rear wheel, 17...Rear axle, 18...Case (final reduction gear case), 19...
・Drive shaft, 28.51... Brake (disc brake, drum brake), 29, 52... Braked member (
disc rotor, drum), 30 ... cover, 31
a, 31b, 60a, Bob--cover half body, 42... telescopic tube (rubber boot).

Claims (1)

[Scope of Claims] A vehicle that has two left and right rear wheels behind the engine, and the power of the engine is transmitted to the rear axle of the rear wheels via a drive shaft extending in the longitudinal direction of the vehicle body, comprising: A braked member of a rear wheel brake is provided on the drive shaft, and at least the periphery of the braked member of the brake is covered with a cover, and the cover can be divided into a pair of cover halves in the axial direction of the drive shaft. At least one of the cover halves is connected to a case or an engine that supports the rear axle via a telescoping tube that is expandable and retractable in the axial direction of the drive shaft. Brake system for vehicles with two rear wheels.