JPH0512505Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wet brake system for a vehicle, and particularly to one installed in an axle system having a planetary gear reducer.

[Prior art]

In general, a vehicle wet brake system installed on an axle device with a planetary gear reducer consists of a brake disc, a disc plate, a brake plate, an annular piston, etc., and uses hydraulic pressure to control the annular piston provided on the internal gear hub. By driving the brake disc, a brake disc spline-fitted to the drive shaft is sandwiched between a disc plate and a brake plate to perform braking.

Conventionally, the outer circumferential portions of the disc plate and brake plate are spline-fitted to the internal gear of a ring member of an internal gear hub, and the ring member supports the braking torque acting on the disc plate and brake plate. There is.

Further, movement of the brake plate in the axial direction of the ring member is regulated by an annular stopper that is spline-fitted with an internal gear of the ring member on the outer side of the brake plate and is fixed to the ring member with a bolt.

[Problem that the invention attempts to solve]

In conventional wet brake devices, spline teeth are formed on the outer periphery of the brake plate for spline engagement with the internal gear of the ring member, which increases the manufacturing cost of the brake plate.

In addition, the stopper that restricts the axial movement of the brake plate was spline-fitted to the ring member and fixed to the inner circumferential surface with bolts.
It is difficult to install and remove the stopper, making it difficult to replace the brake plate efficiently. Moreover, space must be provided in the stopper for bolt attachment, and the stopper becomes thick and the brake device becomes larger in the axial direction. Ta. Moreover, since spline teeth are formed on the outer periphery of the stopper like the brake plate, the manufacturing cost becomes high.

[Means for solving problems]

The wet braking device for a vehicle according to the present invention is a wet braking device for a vehicle that is installed on an axle device having a planetary gear reducer. An annular brake plate is provided between the disks, and partially circular notched engagement portions are formed on the inner periphery of the brake plate corresponding to the planetary pins of the planetary gear reducer, and each planetary pin is provided in each notched engagement portion. By engaging a portion of the brake plate, the rotational torque acting on the brake plate is supported by the planetary pin.

[Effect]

In the wet brake system for a vehicle according to the present invention, an annular brake plate is disposed at a radial position corresponding to the annular piston and between the carrier of the planetary gear reducer and the brake disc, and the inner circumference of the annular brake plate is disposed at a radial position corresponding to the annular piston. A portion of each planetary pin of the planetary gear reducer is engaged with a partially circular notch engaging portion formed in the portion.

When the brake pedal is operated to drive the annular piston, the brake disc is pressed against the brake plate that is in contact with the carrier, and the rotational torque of the brake disc acts on the brake plate, and this rotational torque rotates at a slower speed than the brake disc. It is supported by multiple planetary pins that apply braking force to the brake disc.

[Effect of idea]

According to the wet brake system for a vehicle according to the present invention, as explained above, since the rotational torque acting on the brake plate is supported by a plurality of planetary pins, there is no need to form spline teeth on the outer periphery of the brake plate. The structure of the brake plate can be simplified and manufacturing costs can be reduced.

In addition, since there is no need to provide a stopper or the like to restrict the axial movement of the brake plate, the structure of the brake device can be simplified, the brake plate can be easily replaced, and the axial dimension can be reduced. , the brake device can be configured compactly. Furthermore, the number of parts constituting the brake device can be reduced, and manufacturing costs can be reduced.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, an axle device 2 provided at the shaft end of a drive shaft 1 that drives the drive wheels of a vehicle has a planetary gear reducer 3 as a final reduction device.
and a brake device 4, and is fixed to a tire wheel 6 at the outer periphery of the outer end surface of the carrier 5 of the planetary gear reducer 3.

The axle housing 7 is fitted onto the drive shaft 1 and fixed to the vehicle body, and is attached to the tire wheel 6.
The outer end is fitted into the hub body 9 of the internal gear hub 8 by spline fitting, and the nut 10 is screwed to the end to fix it to the internal gear hub 8. has been done.

The internal gear hub 8 is composed of a hub body 9 and a cylindrical ring member 11. An internal gear 12 is formed on the inner peripheral surface of the ring member 11. Main body 9
The hub body 9 and the ring member 11 are integrally connected by fitting the spline teeth 9a and fitting the stop ring 13 between the internal gear 12 and the hub body 9. However, the hub body 9 and the ring member 11 may be formed integrally.

The outer circumferential side of the internal gear hub 8 is surrounded by a wheel hub 14, and the outer circumferential end of the wheel hub 14 is fixed to the tire wheel 6 with bolts 15 together with the outer circumferential edge of the carrier 5, and the inner inner circumferential portion of the inner gear hub 8 is surrounded by a wheel hub 14. A pair of bearings 32 is housed inside and rotatably supported by the hub body 9 and the axle housing 7.

The planetary gear reducer 3 includes a carrier 5, a ring gear 12 of a ring member 11 of an internal gear hub 8, and a spline shaft portion 16 at an end of a drive shaft 1.
Consisting of a sun gear 17 spline-fitted to the carrier 5, four planetary pins 19 attached to the carrier 5, and four planetary gears 20 rotatably supported by the planetary pins 19 via bearing metals 18. The planet gear 20 meshes with the sun gear 17 and the ring gear 12 of the ring member 11 to rotate around the planet pin 19, and integrally with the carrier 5 and the wheel hub 14 around the drive shaft 1. Tire wheel 6 rotates and is fixed to carrier 5
is rotated at a reduced speed around drive shaft 1.

To explain each of the planet pins 19, an annular washer 21 is provided at an eccentric position on the drive shaft 1 side of the outer end surface.
is fixed with a bolt 22, and an engaging portion 19a cut out in a semicircular shape is formed on the outer side of the drive shaft 1 on the inner end surface, and a notched groove portion is formed approximately at the center of the circumferential surface of the engaging portion 19a. 19b is formed, and both ends of the planetary pin 19 are inserted into and supported by the carrier 5.

The inner periphery of the washer 21 is connected to the carrier 5 and the bolt 2.
The bolt 22 pulls the planet pin 19 and the brake plate 30 outward through the washer 21, and the cover plate 23, which is fixed to the carrier 5 with the bolt 24, The head of the bolt 22 is accommodated in the groove 23a formed on the inner side to prevent the planetary pin 19 from rotating relative to the carrier 5.

The brake device 4 includes a brake cylinder 26 consisting of a substantially annular cylinder groove 9b formed at the outer end of the outer periphery of the hub body 9 and an annular piston 25 fitted in the cylinder groove 9b, and a spline shaft portion. 16, and a disc-shaped brake disc 28 disposed between the carrier 5 and the hub body 9, spline-fitted to the brake sleeve 27, and extended to the vicinity of the ring gear 12. , brake disc 2
A pair of annular friction linings (not shown) are lined on both the inner and outer end surfaces of the brake disc 8 and the ring gear 12 is spline-fitted with the ring gear 12, which is disposed between the brake disc 28 and the piston 25 at a radial position corresponding to the piston 25. It is composed of an annular disc plate 29 having a circular shape, and an annular brake plate 30 disposed between the brake disc 28 and the carrier 5 at a radial position corresponding to the piston 25.

Each planet pin 1 is provided on the inner circumference of the brake plate 30.
A partially circular notch engaging portion 30a at a position corresponding to 9
A protrusion 30b that engages with the notch groove 19b of the engaging portion 19a is formed on the outer side of the inner peripheral surface of the notched engaging portion 30a, and the brake plate 30 is protrudes inward and engages with the notch groove 19b of the planetary pin 19 so as not to contact the brake disc 28 and always abut against the inner end surface of the carrier 5 when the brake pedal (not shown) is not operated. and bolt 2
2 and washer 21, and is adapted to rotate integrally with the carrier 5.

The disk plate 29 is spline-fitted to the ring member 11 so as to be movable in the axial direction and rotationally restrained, and is connected to an oil passage 3 formed in the axle housing 7 and the hub body 9 from a hydraulic pressure supply device (not shown).
When hydraulic pressure is supplied to the brake cylinder 26 through 1, the piston 25 is pressed toward the brake plate 30, and the disc plate 29, brake disc 28, and brake plate 30 are sandwiched between the piston 25 and the carrier 5. , brake disc 28
Apply braking force to A receiving portion 5a for receiving the brake plate 30 is formed on the inner end surface of the carrier 5 facing the brake plate 30.

Next, the operation of the brake device 4 will be explained.

When assembling the brake plate 30 to the planet pin 19, each engagement part 19b of the planet pin 19 is positioned on the drive shaft 1 side and inserted into the carrier 5, so that each notch engagement part 30a is attached to each engagement part 19b. After installing the brake plate 28 correspondingly, rotate each planet pin 19 by 180°.
The notch groove 19b and the protrusion 30b are rotated and assembled by engaging with each other.

The brake plate 30 engages with the engagement portion 19a of the planetary pin 19 at the notch engagement portion 30a, and the carrier 5
The bolt 22 and the washer 2 rotate integrally with the
1, the position of the brake plate 30 and the brake disc 28 is restricted to the outside, and a slight space is left between the brake plate 30 and the brake disc 28.

Each planetary pin 19 rotates integrally with the carrier 5, is pulled outward via a bolt 22 and a washer 21, and is received by a cover plate 23. Further, since the nut portion of the bolt 22 engages with the groove portion 23a of the cover plate 23 and rotationally restrains each planet pin 19, the engagement between the planet pin 19 and the brake plate 30 does not come off.

Next, by operating the brake pedal of the vehicle, hydraulic pressure is supplied to the cylinder 2 from the hydraulic pressure supply device through the oil passage 31.
6, the piston 25 advances outward and the outer end surface of the piston 25 touches the disk plate 2.
9 to press the brake disc 28 toward the brake plate 30, and sandwich the brake disc 28 between the disc plate 29 and the brake plate 30 in a state in which it is brought into contact with the receiving portion 5a of the carrier 5. The rotational torque acting on the brake plate 30 at this time is decelerated by the fixed and non-rotating disk plate 29, and is also decelerated by the planetary pin 19, which is transmitted to the engagement portion 19a of the planetary pin 19, which rotates at a slower speed than the brake disk 28. and is simultaneously decelerated by carrier 5.

In the vehicle wet brake system of the present invention,
As explained above, the engaging portion 19a of the planetary pin 19 is connected to the notch engaging portion 30a on the inner circumferential surface of the brake plate 30.
Since the brake plate 30 is engaged and fixed, the structure of the brake plate 30 is simple and the manufacturing cost can be reduced.

In addition, since the brake plate 30 can be removed simply by removing the bolts 15, 22, and 24, the brake plate 30 can be easily replaced.

Further, since the brake plate 30 is always pulled outward by the washer 21, a constant distance can be maintained between the brake plate 30 and the brake disc 28.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional view of the axle device, and FIG. 2 is a cross-sectional view of the axle device.
FIG. 2...Axle device, 3...Planetary gear reducer,
4...brake device, 5...carrier, 19...
Planetary pin, 25... Piston, 28 Brake disc, 30... Brake plate, 30a... Notch engaging portion.

Claims (1)

[Scope of Claim for Utility Model Registration] In a wet brake system for a vehicle installed on an axle device having a planetary gear reducer, there is provided a vehicle between the carrier of the planetary gear reducer and the brake disc at a radial position corresponding to the annular piston of the brake device. An annular brake plate is provided, a partially circular notch engaging portion is formed on the inner circumferential portion of the brake plate corresponding to the planetary pin of the planetary gear reducer, and a portion of each planetary pin is inserted into each notch engaging portion. A wet type brake device for a vehicle, characterized in that the planetary pin is configured to support rotational torque acting on a brake plate when engaged with the planetary pin.