JP2021095069A - Vehicular braking device - Google Patents

Abstract

To provide a vehicular braking device capable of securing reliability of brake piping in a vehicle adopting a beam type De Dion axle.SOLUTION: A vehicle with a De Dion axle includes: a drive shaft coupled to a wheel 8; a hollow member 41 accommodating a part of the drive shaft in an inner space thereof; a beam member coupling the hollow member 41, the beam member including a connection surface 35 connected to the hollow member 41, a back surface 36 opposed to the connection surface 35 and a coupling surface 37 continuing the connection surface 35 and the back surface 36 and opposed to the wheel; a braking mechanism 60 generating braking force in the wheel 8; and brake piping 70 transmitting hydraulic pressure generated through a brake pedal operation to the braking mechanism 60. The brake piping 70 includes: an L-shaped rigid pipe 72 continuously extending from the back surface 36 to the coupling surface 37 of the beam member; and a flexible hose 73 having one end connected to the L-shaped rigid pipe 72 and the other end connected to the braking mechanism.SELECTED DRAWING: Figure 3

Description

The present invention relates to a vehicle braking device.

In recent years, for the purpose of reducing unsprung weight, it has been considered to adopt a De Dion axle as an axle in commercial vehicles such as trucks. In addition, as a braking device used in a vehicle, a hydraulic type such as a disc type brake that is driven by transmitting hydraulic pressure to a piston in a brake mounted on a wheel through a brake pipe such as a brake hose made of a rubber hose. A braking device is known (Patent Document 1).

JP-A-2017-196930

When a De Dion axle is used in a commercial vehicle such as a truck, it is conceivable that the De Dion pipe will be beamed to ensure strength. In that case, it is necessary to secure a connecting surface between the saddle and the beam, and the beam end surface is adjacent to the wheel.

As a result, the space for disposing the brake pipe between the axle beam and the wheel of the wheel is reduced, and the risk of interference between the brake hose and the wheel during traveling is increased. As a result, the reliability of the brake piping may not be guaranteed.

From the above, the problem to be solved in the present application is to provide a vehicle braking device capable of ensuring the reliability of the brake piping in a vehicle adopting a beam type De Dion axle.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following aspects or application examples.

(1) The vehicle braking device according to this application example is a vehicle braking device that applies braking force to the wheels of the vehicle by using the hydraulic pressure generated by operating the brake pedal in a vehicle equipped with a dodion axle. A pair of drive shafts connected to the wheels, a pair of hollow members accommodating a part of the pair of drive shafts in the internal space, and a beam member connecting the pair of hollow members. A beam member including a connecting surface connected to the hollow member, a back surface facing the connecting surface, a connecting surface connecting the connecting surface and the back surface and facing the wheel, and a control inside the wheel. The braking mechanism includes a braking mechanism for generating power and a brake pipe for transmitting the hydraulic pressure generated by the operation of the brake pedal to the braking mechanism, and the brake pipe is continuous from the back surface of the beam member to the connecting surface. Includes an L-shaped rigid pipe extending from the ground and a flexible hose having one end connected to the L-shaped rigid pipe and the other end connected to the braking mechanism.

As described above, according to the vehicle braking device according to the present application example, the connecting surface of the beam member connecting the pair of hollow members of the Dodion axle is connected to the connecting surface connected to the hollow member and the back surface facing the connecting surface. A brake pipe can be formed by an L-shaped rigid pipe that continuously extends from the back surface to the connecting surface on the connecting surface that connects the surface and the back surface and faces the wheels. Therefore, even if the space for arranging the brake pipe between the axle beam and the wheel of the wheel is small, the risk of interference between the brake pipe and the wheel can be reduced by configuring the brake pipe with the rigid L-shaped pipe, and the brake. The reliability of the piping can be ensured.

It is an upper view (a) and a side view (b) which show the outline of the vehicle braking device and the suspension device of the vehicle which concerns on one Embodiment of this invention. It is a figure which shows typically the hydraulic vehicle braking system including the braking device for a vehicle which concerns on one Embodiment of this invention. It is a detailed view of the part B of FIG. 1 which shows the braking device for a vehicle which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an upper view (a) and a side view (b) showing an outline of a braking mechanism 60 included in a hydraulic vehicle braking system 50 of a vehicle according to an embodiment of the present invention, and a suspension device. The side view of FIG. 1 (b) shows a partially simplified cross section of FIG. 1 (a) along the line AA. Further, the same reference numerals are given to the same configurations on the left and right sides with respect to the center of the vehicle. This suspension device is a De Dion type suspension device, and is, for example, a rear axle provided at the rear of an electric commercial vehicle (hereinafter referred to as a vehicle) such as an electric truck.

The vehicle is equipped with a motor 2 as a traveling drive source, and the driving force of the motor 2 is a power transmission mechanism 4 including a reduction gear composed of a plurality of reduction gears and a differential gear connected to the reduction gear, and a pair of drive shafts. It is transmitted to the left and right wheels 8 via 6 in order. The wheels 8 are supported by a side rail (vehicle body) 10 extending in the front-rear direction Y of the vehicle via a suspension device. Further, the power transmission mechanism 4 including the motor 2 and the differential gear is supported on the vehicle body side (not shown). These members can be supported on the vehicle body side via, for example, a cross member of the frame or the side rail 10.

The suspension device is composed of a pair of spindles 12, a pair of saddles (hollow members) 41, a pair of leaf springs (elastic bodies) 16, an axle beam (beam members) 31, and the like. The spindle 12 is a pair of members provided at both ends in the vehicle width direction X.

The hub 20 is connected to the end of the spindle 12 on the outside of the vehicle, and the wheel 9 is attached to these hubs 20. A rubber tire is attached to the wheel 9 to form the wheel 8.

The braking mechanism 60 has a function of generating a braking force with respect to the wheel 8 inside the wheel 8. Details will be described later. The braking mechanism is connected to 60, a brake pipe 70 that transmits the brake hydraulic pressure generated by operating the brake pedal described later. The brake pipe 70 includes an L-shaped rigid pipe 72, a flexible hose 73 that connects one end of the L-shaped rigid pipe and the braking mechanism 60, and a flexible hose 71 that connects to the other end of the L-shaped rigid pipe. The L-shaped rigid pipe is a metal pipe whose middle portion is bent into an L-shape, and has rigidity to withstand deformation due to external stress. On the other hand, the flexible hoses 71 and 73 are tube members made of a material such as rubber such as butyl chlorinated or resin such as polytetrafluoroethylene, and can be deformed by external stress. The L-shaped rigid pipe 72 may be made of a material such as ceramic or resin having a higher rigidity than the flexible hoses 71 and 73. Further, the angle of the bent portion of the L-shaped rigid pipe 72 does not necessarily have to be a right angle, and the directions of one end and the other end of the opening of the pipe may be changed.

The inner end of the pair of drive shafts 6 located inside the vehicle in the vehicle width direction X is composed of a flexible joint 22 and is connected to the gear of the power transmission mechanism 4. Further, a part of the flexible joint 22 is covered with the boots 24.

The pair of saddles 41 are a pair of hollow members joined to the inner end of each spindle 12 in the vehicle width direction X. Each saddle 41 communicates with the spindle 12 inside, and each drive shaft 6 is housed in the internal space. Each saddle 41 is connected to a leaf spring 16 by a U-bolt.

The leaf spring 16 extends in the front-rear direction Y of the vehicle and is connected to each side rail 10 to elastically support the vehicle body.

The axle beam 31 is a member connected to each saddle 41 and is joined to each spindle 12 and each saddle 41 to form an axle structure 30. The axle beam 31 is supported by the side rail 10 via a shock absorber (not shown), and supports each wheel 8 while ensuring the rigidity of the axle structure 30.

The axle beam 31 extends with a connecting portion 32 extending in the vehicle width direction X and a pair of extending portions 33 extending from the connecting portion 32 in the vehicle width direction X and the vehicle front-rear direction Y, that is, inside the rear rear of the vehicle. A pair of axle end portions 34 extending from the existing portion 33 in the vehicle width direction X are formed as a plate-shaped integral forged product having a predetermined width.

As described above, in the above-mentioned suspension device, each leaf spring 16 suspends the axle structure 30, each drive shaft 6, and each wheel 8 under the spring and elastically supports them.

In the present embodiment, the form of connecting to the leaf spring 16 on the seating surface on the upper surface of the saddle 41 will be described, but the present invention is not limited to this, and the leaf spring 16 is connected to the seating surface on the lower surface of the saddle 41. It can be applied to the form of connecting with. Further, as the elastic body, an air spring may be used instead of the leaf spring 16.

FIG. 2 is a diagram schematically showing a hydraulic vehicle braking system 50 of a vehicle according to an embodiment of the present invention. The hydraulic vehicle braking system 50 in the present embodiment includes four braking mechanisms 60 that brake each of the four wheels.

The hydraulic vehicle braking system 50 includes a brake pedal 51, which is one of the means for instructing these braking mechanisms 60 to brake. The brake pedal 51 is, for example, a foot brake operated by the driver's foot.

A brake booster 52, a master cylinder 53, and a hydraulic pressure adjusting unit 59 are arranged between the brake pedal 51 and each braking mechanism 60. Further, a brake fluid tank 54 for supplying the brake fluid to the master cylinder 53 is provided.

The brake booster 52 is a booster for the brake pedal 51 and is connected to the vacuum tank 55 and the vacuum pump 56 by an air pipe. The brake booster 52 assists the pedaling force applied to the brake pedal 51 by the decompressed air generated by the vacuum tank 55 and the vacuum pump 56, and even when the pedaling force is relatively light, the brake hydraulic pressure is increased to sufficiently brake. It helps to obtain.

The master cylinder 53 has a function of converting the pedaling force of the brake pedal 51 into brake fluid pressure. When the driver operates the brake pedal 51, the brake fluid is supplied from the brake fluid tank 54 to the master cylinder 53 according to the amount of operation. As a result, the master cylinder 53 generates the brake fluid pressure. The brake hydraulic pressure generated by the master cylinder 53 is transmitted to the hydraulic pressure adjusting unit 59 through the main brake pipes 58a and 58b.

The hydraulic pressure adjusting unit 59 has a function of distributing the transmitted brake hydraulic pressure to the brake pipe 70 corresponding to each braking mechanism 60. The distributed brake fluid pressure is further transmitted to each braking mechanism 60 via each brake pipe 70.

The hydraulic pressure adjusting unit 59 is, for example, a hydraulic unit. The hydraulic pressure adjusting unit 59 includes a pump and a valve mechanism that increase and decrease the pressure so as to generate and / or adjust the brake hydraulic pressure transmitted to each braking device. Therefore, the brake fluid pressure can be independently generated / adjusted without using the master cylinder 53. As a result, the hydraulic pressure adjusting unit 59 can realize, for example, an anti-lock braking system by individually controlling the brake hydraulic pressure transmitted to each braking mechanism 60.

FIG. 3 is a detailed view of part C of FIG. 1, which is a diagram schematically showing a braking mechanism 60 included in the hydraulic vehicle braking system 50 of the vehicle according to the embodiment of the present invention.

The axle end 34 has an axle-side connecting surface 35 that is joined to the saddle 41. Further, the axle side back surface 36 facing the axle side connection surface 35, the axle side connection surface 35 and the axle side back surface 36 are continuous, and have a connecting surface 37 facing the wheel 8. The axle end 34 is joined to the saddle 41 by screwing a bolt inserted from the back surface 36 on the axle side with a bolt receiving portion provided on the saddle 41.

The braking mechanism 60 is a so-called disc brake system including a caliper 61, a piston 62, a brake pad 65, and a brake disc 66. A cylinder into which the piston 62 is inserted is formed in a part of the caliper. A worn brake pad 65 is attached to the piston 62 facing the caliper 61. Further, a disc-shaped brake disc 66 is arranged between the caliper 61 and the piston 62. The brake disc 66 is connected to the hub 20 and rotates with the wheel 9, that is, the wheel 8. Although only one piston is shown in FIG. 3, the braking mechanism 60 may have a plurality of pistons, or a plurality of pistons may be arranged so as to face each other with the brake disc 66 in between. I do not care. Further, the caliper 61 is connected to the saddle 41 via the bracket 64. The caliper 61 and the bracket 64 can be connected in a displaceable relative positional relationship.

A brake pipe 70 is connected to the braking mechanism 60. The brake pipe includes an L-shaped rigid pipe 72 and a flexible hose 73 having one end connected to the L-shaped rigid pipe 72 and the other end connected to the braking mechanism 60. Further, the flexible hose 71 connected to the other end of the L-shaped rigid pipe 72 is connected to the hydraulic pressure adjusting unit 59 of FIG. 2, and the brake hydraulic pressure is supplied via the flexible hose 71.

The brake fluid pressure generated by the driver operating the brake pedal 51 is formed on the caliper 61 of the braking mechanism 60 via the brake pipe 70, that is, the flexible hose 71, the L-shaped rigid pipe 72, and the flexible hose 73. It is supplied to the cylinder. The brake fluid pressure in the cylinder pushes out the piston 62 and presses the brake pads against the brake disc 66. At the same time, the position of the caliper 61 is changed by the reaction force that the piston 62 is pushed out, and the brake pad provided on the caliper 61 side is pressed against the brake disc 66. That is, the brake pads attached to the caliper 61 and the piston 62 are pressed against the brake disc 66 by the brake hydraulic pressure. Since the caliper 61 and the saddle 41 are connected to the braking mechanism 60, the wheels 8 can be braked by generating a braking force on the brake disc 66.

Here, since the caliper 61 is displaced, the flexible hose 73 for supplying hydraulic pressure to the cylinder in the caliper 61 needs to be deformable. Further, since the suspension device moves up and down depending on the traveling state of the vehicle, the flexible hose 71 that supplies the brake fluid pressure to the braking mechanism 60 attached to the suspension device also needs to be deformable.

The suspension device according to the present embodiment is configured such that the saddle 41 to which the caliper 61 of the braking mechanism 60 is attached is joined to the axle end 34, which is the end of the axle beam 31, by bolts. It is necessary to secure a connecting surface between the saddle 41 and the axle end 34, and the axle end 34 is adjacent to the wheel 9. Further, in the axle end 34, since the axle side rear surface 36 is adjacent to the wheel 9 for arranging the bolts, the space between the axle side rear surface 36 and the inner surface of the wheel 9 is small. Here, an L-shaped rigid pipe 72 that continuously extends from the axle-side back surface 36 of the axle beam 31 to the connecting surface 37 can be arranged, and the flexible hoses 71 and 73 can be connected to the L-shaped rigid pipe 72. Since the L-shaped rigid pipe 72 is not deformed, there is a risk that the flexible hose will be deformed and interfere with the inner surface of the wheel 9, which may occur when the flexible hose is installed in the space between the rear surface 36 on the axle side and the inner surface of the wheel 9. Can be reduced.

From the above, according to the vehicle braking device according to the present invention, the reliability of the brake piping can be ensured in the vehicle adopting the beam type De Dion axle.

This completes the description of the embodiment of the vehicle braking device 1 according to the present invention, but the embodiment is not limited to the above embodiment.

1 Vehicle braking device 2 Motor 4 Power transmission mechanism (differential gear)
6 Drive shaft 8 Wheels 9 Wheels 10 Side rails 12 Spindles 16 Leaf springs (elastic body)
20 Hub 22 Flexible Joint 24 Boots 30 Axle Structure 31 Axle Beam 32 Connecting Part 33 Extending Part 34 Axle End 35 Axle Side Connecting Surface 36 Axle Side Rear 37 Axle Side Connecting Surface 41 Saddle 42 Saddle Side Joint Surface 50 Hydraulic Vehicle Brake system 51 Brake pedal 52 Brake booster 53 Master cylinder 54 Brake fluid tank 55 Vacuum tank 56 Vacuum pump 58a, 58b Main brake piping 59 Hydraulic pressure adjustment unit 60 Braking mechanism 61 Caliper 62 Piston 64 Bracket 65 Brake pad 66 Brake disc 70 Brake piping 71, 73 Flexible hose 72 L-shaped rigid pipe

Claims (1)

A vehicle braking device that applies braking force to the wheels of the vehicle by using the hydraulic pressure generated by operating the brake pedal in a vehicle equipped with a De Dion axle.
A pair of drive shafts connected to each of the pair of wheels,
A pair of hollow members that accommodate a part of the pair of drive shafts in the internal space,
A beam member that connects the pair of hollow members, the connecting surface that connects to the hollow member, the back surface that faces the connection surface, and the connection surface and the back surface that are continuous and face the wheel. A beam member with a surface,
A braking mechanism that generates braking force inside the wheel,
A brake pipe that transmits the hydraulic pressure generated by operating the brake pedal to the braking mechanism, and
Including
The brake pipe includes an L-shaped rigid pipe that continuously extends from the back surface of the beam member to the connecting surface, and a flexible hose that has one end connected to the L-shaped rigid pipe and the other end connected to the braking mechanism. Braking device for vehicles including.

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