JP3922981B2 - Braking structure for passenger work vehicles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a braking structure of a riding service vehicle of excellent durability for demonstrating a stable braking function for a long time. <P>SOLUTION: Wet type multiple disk front wheel brakes 90 and wet type multiple disk rear wheel brakes 70 are brake-operated by pressure oil fed from a master cylinder 102, an operation lever 73a to operate the rear wheel brakes 70 is connected to a hydraulic cylinder 100 operated by the pressure oil fed from the master cylinder 102, and an operation lever 73a of the right and left rear wheel brakes 70 is connected in an interlocking manner to a single parking tool 104 via a mechanical interlocking mechanism having an equalizer function. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a braking structure for a passenger work vehicle used for various purposes such as transportation of various equipment and materials.
[0002]
[Prior art]
As a brake structure for the passenger work vehicle, for example, as disclosed in JP-A-2002-39235, a structure using a drum brake is known.
[0003]
[Problems to be solved by the invention]
The drum brake has a structure in which the brake shoe mounted on the drum is pressed against the inner surface of the drum, so that the brake performance tends to be greatly deteriorated as the wear of the shoe progresses, and maintenance for the wear is necessary. In particular, passenger work vehicles often run on rough terrain and rough roads, and a considerably large braking load may be applied to the brake. Frequent maintenance is required to ensure a reliable braking function. It was.
[0004]
It is an object of the present invention to provide a braking structure for a passenger work vehicle that can exhibit a stable braking function for a long period of time and has excellent durability.
[0005]
[Means for Solving the Problems]
[Configuration, Action, and Effect of Invention of Claim 1]
[0006]
Braking structure passenger work vehicle according to the invention of claim 1, the axle case before the right and left front wheels are supported lifting the front axle is mounted to support the right and left to each other via a suspension mechanism, the front axle case In the brake structure of a passenger work vehicle that incorporates a wet multi-plate type front wheel brake and has a wet multi-plate type rear wheel brake in the rear wheel drive system ,
The front axle has a flange portion for attaching a front wheel on one end side, the other end side is connected to a transmission shaft on the upper transmission side, and a friction plate group for front wheel brakes is attached to an intermediate portion in the axial direction. And is supported on the front axle case via bearing portions arranged on both sides of the friction plate group,
A brake chamber in which the friction plate group is accommodated inside the front axle case is formed, and between the friction plate group and the flange portion, and inside the front axle case on the radially outer side of the bearing portion, In addition to the brake chamber, a lubricating oil chamber having a lubricating oil storage space and connected to the brake chamber is formed .
[0007]
According to the above configuration, the wet multi-plate type brake that presses the friction plate group in the lubricating oil to exert the braking force is highly waterproof and heat resistant, and has a good braking function stably over a long period of time. It can be demonstrated. Further, since braking is applied to the front wheels and the rear wheels, powerful braking can be performed.
Further, according to the above configuration, since the lubricant chamber communicating with the brake chamber containing the friction plate group is provided in the front axle case separately from the brake chamber, even if the volume of the brake chamber containing the friction plate group is small A lot of lubricating oil can be held in the front axle case.
[0008]
Therefore, according to the invention of claim 1, constituting the braking structure passenger work vehicle which is excellent in durability with rough terrain or even traveling on rough road stable and reliable braking function can be a long period of time exhibit be able to.
[0009]
[Configuration, Action, and Effect of Invention of Claim 2]
[0010]
According to a second aspect of the present invention, in the first aspect of the invention, the front wheel brake and the rear wheel brake are configured to be braked by pressure oil supplied from a master cylinder.
[0011]
According to the above configuration, the front wheel brake and the rear wheel brake can be braked simultaneously by operating the master cylinder with a brake pedal or the like to send out pressure oil. In this case, it is possible to configure a brake that can provide a large braking force even with a relatively small hydraulic pressure by increasing the number of friction plate groups or increasing the diameter of the friction plate groups.
[0012]
Therefore, according to the invention of claim 2, while providing the above-mentioned effect of the invention of claim 1, it can be effectively used as a brake structure suitable for a passenger work vehicle in which a strong braking function is desired.
[0013]
[Configuration, Action, and Effect of Invention of Claim 3]
[0014]
According to a third aspect of the present invention, in the second aspect of the present invention, the operating lever for operating the rear wheel brake is linked to a hydraulic cylinder that is operated by pressure oil supplied from the master cylinder, and the left and right rear wheel brakes are connected. The operation lever is linked to a single parking operation tool through a mechanical linkage mechanism having an equalizer function.
[0015]
According to the above configuration, when the vehicle is stopped, the master cylinder is operated to brake the front wheel brake and the rear wheel brake at the same time. When the vehicle is parked, only the rear wheel brake is braked with human operation force by operating the parking operation tool. Let In this case, the friction plate pressure contact force caused by operating the parking operation tool is smaller than the friction plate pressure contact force caused by the hydraulic operation, but the braking force at the time of parking should be such that the vehicle body does not move due to its own weight even on a sloping ground. Well, there are no practical problems.
[0016]
Therefore, according to the invention of claim 3, the front wheel and the rear wheel can be braked at the same time to reliably stop traveling, and braking can be applied at the time of parking with an inexpensive structure without providing a dedicated parking brake. .
[0017]
[Configuration, Action, and Effect of Invention of Claim 4]
[0018]
According to a fourth aspect of the invention, in the invention of the second or third aspect, the front wheel brake includes a friction plate pressing piston that operates by being supplied with pressure oil, and the return position of the piston in the brake release direction is provided. It is configured to be adjustable.
[0019]
According to the above configuration, the front wheel case incorporated in the front axle case is operated by the piston, so that the front axle case can be downsized compared to the case where the front wheel brake is operated by the hydraulic cylinder. This is advantageous for the front axle case being directed. In addition, by adjusting the piston reverse return position, it is possible to minimize the play of the piston when braking and to increase the response of the braking operation.
[0020]
Therefore, according to the invention of claim 4, the effect of the invention of claim 2 or 3 is brought about, and the steered front wheel can be braked accurately.
[0021]
[0022]
[0023]
[0024]
[0025]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the entire side surface of the work vehicle according to the present invention, and FIG. 2 shows the entire plane. This work vehicle includes a two-seater specification driving unit 4 at a front and rear intermediate portion of a four-wheel traveling vehicle body 3 having left and right front wheels 1 to be steered and left and right rear wheels 2 fixed in direction. At the same time, the vehicle is configured as a four-wheel drive vehicle provided with a rear loading unit 5 behind the operation unit 4. In this example, a dump bed 6 is provided on the rear loading unit 5.
[0026]
3 to 7 show the structure of the vehicle body frame in the traveling vehicle body 3.
The main frame 7 of the vehicle body frame is composed of a pair of left and right front main frames 7a made of a square pipe material, and a rear main frame 7b connected to the rear end of the main frame 7 in a stepped manner through a vertical frame 7c. A front frame 8, a driving unit frame 9, a seat support frame 10, an engine mounting frame 11, a mission support frame 12, and the like are connected to the main frame 7, and a sheet metal erected on the left and right above the front end of the driving unit frame 9 A four-column protective frame 15 that covers the operating unit 4 is flange-connected across the upper end of the front mast 13 of the structure and the upper end of a rear mast 14 made of pipe standing on the left and right ends of the operating unit frame 9. ing.
[0027]
The protective frame 15 is composed of a pair of left and right portal frames 15a connected to the front mast 13 and the rear mast 14, and a plurality of stays 15b connecting them, as indicated by phantom lines in FIG. In addition, a sunshade 16 is attached to the upper end of the protective frame 15 as necessary.
[0028]
A front cover 17 is attached to the front of the vehicle body. The front cover 17 includes a lower cover 17 a that covers the front frame 8 from the front and left and right sides, and a front upper cover 17 b that covers the front frame 8, the upper part of the operation unit frame 9, and the front mast 13. In the front cover 17, a radiator 18 with an electric fan connected to an engine 30 described later is accommodated. Further, a step 20 is stretched under the front main frame 7a and the driving unit frame 9, and various operation levers such as a steering handle 21 and a front panel are mounted on the driving unit frame 9. Is done. Further, a driver's seat 22 and a passenger's seat 23 are mounted on the seat support frame 10 so as to be able to lift and rotate, and a driver rear cover 24 covering the seat support frame 10 and the rear mast 14 is provided. .
[0029]
The left and right engine mounting frames 11 are mounted and supported by front and rear, left and right vibration-proof rubbers (not shown) on the engine 30 with the crankshaft centered in the front-rear direction, and a transmission case 31 is connected to and supported by the transmission support frame 12. A hydraulic continuously variable transmission 32 that receives engine power is provided at the front of the transmission case 31.
[0030]
As shown in FIGS. 9 to 11, the mission support frame 12 is pivotally coupled across brackets 33 a and 34 a of horizontal frames 33 and 34 that are horizontally mounted on the lower front portion and the upper rear portion of the main frame 7. The rubber bushes 35 are inserted into the shaft support connecting portions at both ends of the frame so that the transmission vibration is absorbed.
[0031]
As shown in FIGS. 12 and 13, the continuously variable transmission 32 includes an axial plunger type variable displacement pump 36 and an axial plunger type fixed displacement motor 37 that are vertically moved in a casing formed integrally with the front portion of the transmission case 31. Are arranged side by side and closed from the front by the port block 38. The swash plate angle of the pump 36 is changed to change the pressure oil supply direction and the supply amount from the pump 36 to the motor 37, thereby providing a motor output. The shaft 39 is configured to continuously change in a forward and reverse direction. Then, the pump input shaft 40 is driven in conjunction with the engine 30 via a shaft transmission mechanism 42 having a pair of universal joints 41 interposed therebetween, and the shifting power extracted from the motor output shaft 39 is input to the mission case 31. Are transmitted to the left and right rear wheels 2, and part of the transmission power is transmitted to the front differential device 45 via the universal joint 43 and the transmission shaft 44 to drive the left and right front wheels 1. ing.
[0032]
The continuously variable transmission 32 uses the lubricating oil stored in the transmission case 31 as hydraulic oil, pressurizes the oil taken out via the strainer 46 with the charge pump 47, and the charge oil passage of the continuously variable transmission 32. The drain oil is reduced into the mission case 31. The upper surface of the transmission case 31 is provided with an oil filter 48 for purifying charge oil, and the shaft transmission mechanism 42 is provided with a fan 49 for cooling the continuously variable transmission 32.
[0033]
The transmission case 31 is provided with a gear-type sub-transmission mechanism 50 that shifts the power from the motor output shaft 39 in two steps of high and low in a constant mesh form. That is, the subtransmission mechanism 50 is provided between the first shaft 51 that is gear-linked to the motor output shaft 39 and the second shaft 52 that is disposed confrontingly with the motor output shaft 39. The shift sleeve 53 splined on the two shafts 52 is shifted to the right in the drawing of FIG . 12 and meshed with the boss of the large diameter gear 54 loosely fitted to the first shaft 51, whereby the motor output is changed to the gear 55, The second shaft 52 can be driven at a low speed by the speed reduction between 56 and the speed between the gears 57 and 54, and the shift sleeve 53 is shifted leftward in FIG. As a result, the second shaft 52 is driven at high speed.
[0034]
The power shifted by the sub-transmission mechanism 50 having the above configuration is transmitted from the second shaft 52 to the bevel pinion shaft 60 via the gears 58 and 59 and then the differential device 62 with a differential lock via the bevel pinion gear 61. Is extracted from the left and right rear wheel drive output shaft 63 which is the differential shaft of the differential device 62. The left and right rear wheels 2 are pivotally supported via a bearing block 66 supported by a leaf spring 64 and a shock absorber 65, and linked to the rear wheel drive output shaft 63 via a pair of universal joints 67 and a transmission shaft 68. Has been.
[0035]
A brake case 69 is assembled to the left and right sides of the mission case 31. The brake case 69 is provided with a rear wheel drive output shaft 63 and a wet multi-plate type rear wheel brake 70. The rear wheel brake 70 brakes the output wheel 63 for driving the rear wheel by pressing the friction plate 71 group interposed between the output shaft 63 for driving the rear wheel and the inner surface of the brake case 69 with the pressing plate 72. The operation of the operation shaft 73 mounted on the brake case 69 and the rotation of the pressing plate 72 around the output shaft axis cause the pressing plate 72 to rub due to the action of the ball cam 74. the plate 71 group by releasing pressing or pressing, the braking force to the rear wheel driving output shaft 63 is adapted to be applied or released.
[0036]
When assembling, the rear wheel drive output shaft 63 is pre-assembled to the brake case 69 together with the brake components, and the pre-assembled brake case 69 is attached to the left and right side surfaces of the transmission case 31. The differential device 62 is supported between the brake cases 69.
[0037]
The power of the bevel pinion shaft 60 is transmitted to the front wheel drive output shaft 80 via the shift gear 76, the idle gear 77, the clutch gear 78, and the clutch sleeve 79 that is spring-engaged and engaged with the clutch gear 78. The power extracted from the front wheel drive output shaft 80 is transmitted to the front differential device 45 through the transmission shaft 44 as described above, and the front wheel 1 is driven at a speed synchronized with the rear wheel 2. Here, when the front wheel drive system is reversely driven at the time of turning and starts to rotate at a higher speed than the rear wheel drive system, the clutch sleeve 79 is automatically retracted from the clutch gear 78 to transmit power to the front wheel drive system. Refused. Further, by manually operating the shift gear 76 so as to be disengaged from the idle gear 77, it is possible to obtain a two-wheel drive state in which the driving of the front wheels 1 is stopped and only the rear wheels 2 are driven to travel.
[0038]
The left and right front wheels 1 are pivotally supported by a front axle case 85 that is independently suspended via a suspension mechanism 84. As shown in FIG. 15, the suspension mechanism 84 extends from the vehicle body frame so as to be swingable up and down. A suspension arm 81, a suspension spring 82, a shock absorber 83, and the like are included. A front axle 87 mounted on the front axle case 85 and a transmission shaft 86 extending from the front differential device 45 are connected by a ball-type shaft joint 88, and a flange 87a provided at the outer end of the front axle 87 is provided. The front wheel 1 can be attached to the front.
[0039]
The left and right front axle cases 85 are also used as brake cases, and front wheel brakes 90 are respectively incorporated therein. The front wheel brake 90 is constructed in a wet multi-plate type so as to brake the front axle 87 by pressing a friction plate 91 group interposed between the front axle 87 and the inner surface of the front axle case 85 by a ring-shaped piston 92. The piston 92 is advanced and displaced in the braking direction by the pressure oil supplied through the pipe 93, and is returned and displaced in the braking release direction by the return spring 94 and the pressing plate 95. The backward return position of the piston 92 can be changed by adjusting the advance / retreat of the adjusting bolt 96, and this adjustment minimizes the play of the piston 92 when braking and increases the response of the braking operation. Be able to.
The front axle case 85 is pivotally supported by bearings 89 provided on both sides of the friction plate 91, with a front axle 87 having the friction plate 91 group attached to an intermediate portion in the axial direction. A brake chamber 98 for accommodating the friction plate 91 group is formed between the bearing portions 89 on both sides .
Further, the front axle case 85 has the brake chamber as a lubricant chamber connected in communication with the brake chamber 98 in order to secure the amount of lubricant retained in the case and sufficiently ensure the life of the lubricant. An oil storage chamber 97 different from 98 is formed in an annular shape.
[0040]
FIG. 16 shows a brake operation system. An operation lever 73 a is provided at the outer end of the operation shaft 73 for operating the left and right rear wheel brakes 70. A pair of hydraulic cylinders 100 that push and pull each operation lever 73 a are operated by the brake pedal 101. Connected to a master cylinder 102 via a pipe 103. The master cylinder 102 and the front wheel brake are connected by the pipe 93, and the left and right front wheels 1 and the rear wheel 2 can be braked simultaneously by depressing the brake pedal 101. The operation lever 73a is mechanically linked to a parking lever (parking operation tool) 104 via an operation wire 105, a stabilizer link 106, and left and right brake wires 107, and operates the parking lever 104 during parking. Thus, the left and right rear wheels 2 can be braked.
[0041]
As shown in FIG. 13, the rear end of the pump input shaft 40 of the continuously variable transmission equipped in the transmission case 31 is provided with a gear 107 for taking out power and closes the opening 108 formed on the upper surface of the transmission case 31. The power take-out device 109 is attached. The power take-out device 109 includes gears 110 and 111 meshing with the gear 107 in the case and a rear-side power take-out shaft 112, and the hydraulic pump 113 is driven by the taken-out power. .
[0042]
The hydraulic pump 113 serves as a pressure oil source for a dump cylinder (not shown) that moves up and down the loading platform 6, and manually operates by sucking the hydraulic oil stored in the hydraulic oil tank 114 disposed below the left seat. As shown in FIGS. 17 to 19, a metal pipe 116 that is supplied to the control valve 115 of the type and led out from the control valve 115 is provided along the main frame 7 and connected to the coupler 117. 117 and the dump cylinder are connected by a hydraulic hose. Further, it is also possible to use another hydraulically driven implement connected to the coupler 117 by piping.
[0043]
Here, the hydraulic oil tank 114, the control valve 115, the pipe 116, and the support bracket 118 of the coupler 117 are tightened and held at appropriate positions on the main frame 7 by U bolts 119 and clamp fittings 120. These models are not installed on models that do not have a hydraulic option. If there is a request to equip the hydraulic option at a later date, the hydraulic equipment can be easily installed as described above. When the hydraulic option is not installed, the power take-out device 109 and the hydraulic pump 113 are removed from the mission case 21 and the opening 108 is closed with a lid cover 121 as shown in FIG.
[0044]
[Another embodiment]
The present invention can also be implemented in the following forms.
(1) The front wheel brake 90 can also be configured to be operated by a hydraulic cylinder in the same manner as the rear wheel brake 70.
(2) The front wheel brake 90 can also be incorporated in the case of the front differential device 45.
(3) In addition to the parking lever 104, a parking pedal can be used as the parking operation tool.
(4) As a mechanical linkage mechanism that links the parking operation tool and the operation lever 73a of the rear wheel brake 70, an operation rod can be used in addition to using a wire.
[Brief description of the drawings]
1 is an overall side view of a passenger work vehicle. FIG. 2 is an overall plan view of the passenger work vehicle. FIG. 3 is an overall side view showing a vehicle body structure of the passenger work vehicle. ] Overall side view of the frame structure [Fig. 6] Perspective view showing a part of the frame structure [Fig. 7] Perspective view showing the frame structure and upper attachment members [Fig. 8] Plan view of the transmission structure [Fig. 9] Side view [Fig. 10] A longitudinal side view showing the rear end connecting portion of the mission support frame. [Fig. 11] A longitudinal rear view thereof. [Fig. 12] A transverse plan view showing the internal structure of the mission case. [Fig. Fig. 14 is a vertical side view showing the front part of the transmission case when the power take-off device is removed. Fig. 15 is a vertical rear view of the front wheel shaft support. Fig. 16 is a block diagram of the brake operation system. 17] Hydraulic piping a-a sectional view in side view Figure 19 Figure 18 shows a perspective view and FIG. 18 hydraulic pipe structure showing Concrete EXPLANATION OF REFERENCE NUMERALS
DESCRIPTION OF SYMBOLS 1 Front wheel 2 Rear wheel 70 Rear wheel brake 73a Operation lever 85 Front axle case 90 Front wheel brake 100 Hydraulic cylinder 102 Master cylinder 104 Parking operation tool

Claims (4)

The front axle case that supports the front axle to which the left and right front wheels are mounted is supported separately on the left and right via a suspension mechanism, and a wet multi-plate type front wheel brake is incorporated into the front axle case, and the rear wheel drive system is incorporated. A braking structure for a passenger work vehicle equipped with a wet multi-plate type rear wheel brake ,
The front axle has a flange portion for attaching a front wheel on one end side, the other end side is connected to a transmission shaft on the upper transmission side, and a friction plate group for front wheel brakes is attached to an intermediate portion in the axial direction. And is supported on the front axle case via bearings arranged on both sides of the friction plate group,
A brake chamber in which the friction plate group is accommodated is formed inside the front axle case, and between the friction plate group and the flange portion, and inside the front axle case on the radially outer side of the bearing portion, A braking structure for a passenger work vehicle having a lubricating oil storage space separately from the brake chamber and having a lubricating oil chamber connected to the brake chamber .   The braking structure for a passenger work vehicle according to claim 1, wherein the front wheel brake and the rear wheel brake are configured to be braked by pressure oil supplied from a master cylinder.   The operation lever for operating the rear wheel brake is linked to a hydraulic cylinder operated by pressure oil supplied from the master cylinder, the operation levers for the left and right rear wheel brakes are used as a single parking operation tool, and an equalizer function is provided. The brake structure for a passenger work vehicle according to claim 2, wherein the braking structure is interlocked and connected via a mechanical linkage linkage mechanism.   4. The passenger work vehicle according to claim 2, wherein the front wheel brake is provided with a piston for pressing a friction plate that is operated by pressure oil supply, and the return position of the piston in the brake release direction is adjustable. Braking structure.

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