JP2002302022A - Brake device for crawler tractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a mechanism in a brake device of a crawler tractor wherein the driving force of an engine is transmitted to a HST for traveling to execute the gear shift operation by the HST for traveling, and the driving force of the engine is transmitted to a HST for turning to control the traveling by the HST for turning. SOLUTION: A braking mechanism 74 is mounted near a traveling drive taking-out part at a lower part of a transmission case 5 and an auxiliary transmission 41, and when a brake pedal 54 is pressed, the HST for traveling 22 is returned to a neutral position, and then the braking mechanism 74 is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler tractor brake device. More specifically, the present invention relates to a crawler tractor brake device disposed on a crawler tractor that transmits a driving force of an engine into a transmission case disposed rearward and transmits a driving force shifted from a traveling drive take-out portion to a traveling device. is there.

[0002]

2. Description of the Related Art Conventionally, in a differential mechanism of a working vehicle having a crawler-type traveling device, one of gears constituting a planetary gear uses an internal gear, so that the planetary gear has a radial direction. It was getting bigger. In addition, since the steering brakes are provided on the left and right axles, a brake mechanism is required on the left and right, and the brake mechanism is enlarged to brake a large torque.

[0003]

In the prior art, the size of the brake mechanism itself becomes large, and it is necessary to take a large space for disposing the brake mechanism. For this reason,
The degree of freedom in design decreases. Further, when operated by the link mechanism, the overall length of the link mechanism becomes longer.

[0004]

In order to solve the above problems, the present invention uses the following means. A crawler tractor brake disposed on a crawler tractor disposed on a crawler tractor for transmitting a driving force of an engine into a transmission case disposed rearward and transmitting a driving force shifted from a traveling drive take-out portion to a traveling device. The apparatus is provided in a traveling drive take-out section below a transmission case.

According to a second aspect of the present invention, after the driving force of the engine is shifted by the traveling hydraulic continuously variable transmission, it is transmitted into the transmission case, and the driving force shifted by the traveling drive take-out portion is transmitted to the traveling F. A crawler tractor brake device disposed on a crawler tractor that transmits to the device,
When the brake pedal is depressed, the swash plate of the traveling hydraulic continuously variable transmission is returned to the neutral position, and then the parking brake provided on the traveling drive take-out section is operated.

According to a third aspect of the present invention, the engine is provided on a crawler tractor for transmitting the driving force from the traveling drive take-out section to the traveling device via the auxiliary transmission provided in the transmission case. A brake device for a crawler tractor, which is provided at a traveling drive take-out portion below a transmission case and near an auxiliary transmission.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The problems and means to be solved by the present invention are as described above. Next, an embodiment of the present invention shown in the attached drawings will be described. 1 is a front perspective view of a crawler tractor, FIG. 2 is an overall side view, FIG. 3 is a side view showing an arrangement of an engine, an HST and a transmission case, FIG. 4 is a side sectional view showing a configuration inside a rear transmission case, and FIG. 6 is a side view showing an operation device of a crawler tractor, FIG. 6 is a side view showing an operation configuration of a brake pedal, FIG. 7 is a front view thereof, FIG. 8 is a side view showing an operation configuration of a main shift lever, and FIG. FIG. 10 is a diagram showing an interlocking configuration of the main transmission lever and the main transmission lever.
Is a side sectional view showing the structure of the brake mechanism, and FIG. 11 is a plan sectional view of the same.

First, a schematic configuration of a crawler tractor as an embodiment provided with a steering device according to the present invention will be described. As shown in FIGS. 1 and 2, an engine 3 is disposed above a front portion of the crawler traveling device 1, and a rear transmission case 5 is disposed above a rear portion. The engine 3 is covered by a bonnet 4 and the engine 3 is fixed between lower left and right main frames 6,6. A steering column 2 is provided at a rear portion of the hood 4, a round steering handle 7 for performing a steering operation is disposed on the steering column 2, and a seat 8 is disposed behind the steering handle 7. 2 and sheet 8
The step 18 is arranged below and between the steps to constitute an operation unit. These operating parts are covered by a cabin 9. At the rear end of the vehicle, a three-point link type mounting device 10 for mounting various working machines is provided.

The crawler-type traveling device 1 is supported by a crawler frame 15.
A front transmission case 16 is fixed to the front end of the drive sprocket 11 to support the drive sprocket 11, and an idler 12,
Are rotatably supported between the driving sprocket 11 and the idler 12, and a crawler belt 14 surrounds the driving sprocket 11, the idler 12, and the rolling wheels 13, 13. It is winding.

Next, the drive transmission system of the crawler tractor will be described with reference to FIGS. A damper case (or clutch case) 19 is provided at the rear of the engine 3.
The output shaft 42 of the damper in the damper case 19 is extended rearward, and an input of a hydraulic traveling continuously variable transmission (hereinafter referred to as traveling HST) 22 attached to the front of the rear transmission case 5 is provided. Connected to the shaft. In the rear transmission case 5, a sub transmission 41, a PTO transmission 43, and the like are housed. The auxiliary transmission 43 has the traveling H
The output of ST22 is transmitted, and the PTO transmission 43 is connected to the input shaft of the traveling HST 22 via the clutch 44. A traveling drive take-out portion is provided at a lower front portion of the rear transmission case 5, and an output shaft 102 is provided at the traveling drive take-out portion.

A front transmission case 16 is provided in front of the engine 3 with a hydraulic continuously variable transmission for turning (hereinafter referred to as a turning HST) 20 attached to the front.
The front transmission case 16 is supported by a front portion of the main frame 6 and is disposed at a front position of the body. The turning H is driven by the power from the engine 3.
ST20, the output of the turning HST20 and the output from the auxiliary transmission 41 are combined to form a drive sprocket 1
1 is driven. The motor-side output of the traveling HST 22 is input to the differential gear mechanism via the transmission shaft 45 after being shifted by the auxiliary transmission 41. Then, in the differential gear mechanism, it is input to sun gears of planetary gear assays arranged on the left and right. HST2 for turning
The motor output of 0 is divided into two parts, one is directly input to the ring gear of the planetary gear assay, and the other is input to the ring gear via the reverse gear. Thus, the rotation of the motor of the turning HST 20 causes the ring gears to rotate in opposite directions. The combined power of the sun gear and the ring gear is transmitted to the left and right sprockets 11 by a planetary carrier. For this reason, when turning straight, the motor rotation of the turning HST 20 is stopped, and when turning, the motor rotation of the turning HST 20 is gradually increased to enable smooth turning.

In the traveling HST 22, the traveling HST
The output shaft 101 of the traveling HST 22 is driven by the rotation of the input shaft 22. The drive ratio and the rotation direction of the output shaft 101 are controlled by swash plate angle control of the input shaft side hydraulic pump. It is. The driving force of the output shaft 101 is transmitted to the auxiliary transmission 41, and the driving force shifted by the auxiliary transmission 41 is transmitted to the output shaft 102 of the traveling drive take-out unit. The transmission shaft 45 described above is connected to the output shaft 102 of the traveling drive take-out unit. Output shaft 10
A brake mechanism 74 is provided in the vicinity of 2, and the output shaft 102 is braked by the brake mechanism 74. The output shaft 102 is connected to a sun gear that drives the sprocket 11 via the transmission shaft 45. By stopping the output shaft 102, the driving of the sprocket 11 can be stopped and braking can be applied. .

The brake mechanism 74 is provided at a traveling drive take-out section below the transmission case that includes the auxiliary transmission mechanism 41. HST2 for traveling ahead of the auxiliary transmission 41
2 and a brake mechanism 74 is provided below the traveling HST 22. Since the brake mechanism 74 that constitutes the parking brake is provided at the lower part of the rear transmission case 5 where the traveling drive is taken out, the brake mechanism 74 can be provided at a position close to a brake pedal described later. Further, the design of the link mechanism and the like can be easily performed, and the distance between the links can be shortened, so that friction loss and play can be reduced, and operability is improved. Further, due to the structure of the crawler tractor, a large space can be taken below the cabin, between the traveling HST 22 and the engine 3, and the space can be used effectively.

Next, the structure of the turning operation, the main speed change operation and the brake operation will be described. First, in FIG.
The steering 51 is connected to a steering box 52, and the operation of the steering 51 is transmitted to the conical link mechanism 53 via the steering box 52. The main speed change lever 55 is also connected to the conical link mechanism 53 via a link mechanism. And
A brake pedal 54 is provided near the conical link mechanism 53.

The conical link mechanism 53 has a steering 5
1 and an operation from the main shift lever 55 are input. In the conical link mechanism 53, the connecting portion of the link moves along the bottom and side surfaces of the cone. The end points of the straight-moving rod and the turning rod are positioned with a phase difference of 90 degrees to the bottom circle of the cone, and the other end points of both rods are located at the vertices of two large and small cones. The movement of the apex of each straight turning cone is the traveling H
ST, which relates to the position of the operation arm of the turning HST. The turning angle of the main transmission lever 55 is proportional to the inclination of the bottom surface of the cone, and the turning angle of the steering wheel 51 is proportional to the turning angle of the bottom circle of the cone.

In the stopped state, even if the steering wheel 51 is turned in the left-right direction, the distance from the top of the cone to the bottom circle is always equal, and the operating arms of the traveling HST and the turning HST are not moved. Therefore, the traveling HST
And the hydraulic motor of the HST for turning is not driven, and the body continues to stop. Next, when the main transmission lever 55 is tilted in the forward direction, the operation arm of the traveling HST is rotated forward. However, the operation arm of the turning HST does not move irrespective of the inclination of the bottom surface because the end point of the turning rod is located on the rotation center line of the conical bottom surface. For this reason, the operation arm of the turning HST does not move, and the aircraft moves straight. When the steering wheel 51 is turned from this state, the operation arm of the traveling HST moves in the deceleration direction, and the turning HST operation arm moves. That is, as the steering wheel 51 is turned, the body speed is automatically reduced and the vehicle turns. In the reverse state, when the steering wheel 51 is turned, the operation arm of the turning HST moves in a direction opposite to that in the forward movement. As a result, the operation of the turning HST is reversed between the forward movement and the reverse movement, and the reverse handle phenomenon is eliminated.

As described above, by the conical link mechanism 53,
The operation of the steering 51 and the operation of the main transmission lever 55 are linked. Further, in the present embodiment, the operation of the brake pedal 54 is
Or the rotation of the operation arm of the traveling HST.

Next, the link structure of the brake will be described with reference to FIGS. 6 and 7. FIG. The brake pedal 54 is connected to the above-described brake mechanism 74 via a link mechanism.
To activate the parking brake. The brake pedal 54 is fixed to a support shaft 62.
Is rotatably supported at the upper part of the front column. When the brake pedal 54 is depressed, the support shaft 62 rotates together with the brake pedal 54. An arm 63 and an arm 64 are fixed to the support shaft 62, and rods 65 and 66 are connected to tips of the arms 63 and 64, respectively. The rod 65 and the rod 66 are disposed vertically, respectively.
1 is connected. The cam lever 61 is rotatably supported by a support shaft fixed to the side surface of the box containing the conical link mechanism 53, and is configured to rotate up and down as the rod 66 slides up and down.

At the lower end of the rod 65, an arm 68 is provided.
The arm 68 is rotatably supported by a support shaft 67. An arm 69 that rotates integrally is fixed to the arm 68, and a rod 70 is connected to a tip of the arm 69. Rod 7
Numeral 0 is disposed in the longitudinal direction of the fuselage. One end of an L-shaped arm 72 rotatably supported by a support shaft 71 is connected to the rear end of the rod 70. The other end of the L-shaped arm 72 is connected to a vertically arranged rod 73, and the lower end of the rod 73 is connected to an operating arm 113 of a brake mechanism 74. Thus, when the brake pedal 54 is depressed, the operation arm 113 rotates, and the brake mechanism 74 operates. As a result, the brake mechanism 74 can be installed at a position close to the brake pedal 54, which facilitates design, shortens the distance between links, and improves security.

A parking brake lever 75 is provided inside the brake pedal 54 so that the parking brake lever 75 can be locked when the brake pedal 54 is depressed (brake is applied). Have been. By depressing the brake pedal 54 and rotating the parking brake lever 75 upward, the brake pedal 54 is held in the depressed state, and the parking brake is applied. The parking brake is released by rotating the parking brake lever 75 downward.

Next, the link mechanism of the main shift lever 55 will be described with reference to FIG. The lower end of the main transmission lever 55 is pivotally supported on a support shaft 90, and an arm extending forward is fixed to the lower end of the main transmission lever 55. An upper end of a rod 81 is connected to a tip of the arm, and an arm rotatably supported by a shaft 82 is connected to a lower end of the rod 81. The arm supported by the shaft 82 rotates integrally with the arm 83. Thus, by rotating the main speed change lever 55, the arm 83 is rotated back and forth.

A lower end of the arm 83 is connected to a rear end of a rod 91, and a front end of the rod 91 is connected to an arm 84 fixed to a shaft 89. Arm 84 is axis 8
The arm is pivoted in the front-rear direction around the center 9 and a rod 85 is connected to the arm. In addition,
The shaft 89 is connected to the conical link mechanism 53 described above. The rod 85 connects the arm 86 and the arm 84, and the arm 86 is rotatably supported at the lower end. A plate 87 disposed in the front-rear direction is connected to the arm 86, and an arm 88 of the HST 22 is connected to a tip of the plate 87. With such a link mechanism, the main transmission lever 55 is operated to operate the traveling HST 22.

Next, the linkage between the brake pedal 54 and the main shift lever 55 will be described with reference to FIG. As described above, the shaft 89 connected to the conical link mechanism 53 rotates together with the main speed change lever 55. And
One end of an arm 92 is fixed to the shaft 89. When the main shift lever 55 is turned, the arm 92 is turned. When the arm 92 is turned, the main shift lever 55 is also turned. A protrusion 93 is provided at the tip of the arm 92, and the protrusion 93 is configured to protrude in the rotation axis direction of the arm 92. Projection 93
Is located inside the cam portion of the cam lever 61 described above, and the projection 93 comes into contact with the inside of the cam of the cam lever 61 by the rotation of the cam lever 61.

When the brake pedal 54 is depressed, the cam lever 61 rotates, and the arm 92 is returned to a predetermined position by the cam lever 61. The position where the arm 92 is returned by the cam lever 61 corresponds to the neutral position of the main transmission lever 55. Therefore, by depressing the brake pedal 54, the main shift lever 55 is returned to the neutral position, and the brake mechanism 7 is depressed.
4 is operated. That is, the travel HST 22 and the brake mechanism 74
The system can be operated. Then, by operating the brake pedal 54, first, the main transmission lever 55 connected to the traveling HST 22 is returned to the neutral position, and the traveling HST 2
2 to apply the brake. The parking mechanism can be operated by the brake mechanism 74. Thus, the braking force by the HST and the braking force by the brake mechanism 74 can be used. Since the brake mechanism 74 is configured to apply a brake after braking by the HST, the brake mechanism 74 can be configured to be small. Further, by adjusting the operation timings of the two brakes, the wear of the parking brake in the brake mechanism 74 can be prevented.

Next, the structure of the brake mechanism 74 will be described with reference to FIGS. The output shaft 102 is rotatably held by a transmission case 107 and a brake cover 108 via bearings, and a gear 106 is inserted and fixed to the rear end of the output shaft 102. The gear 106 meshes with the gear of the auxiliary transmission mechanism 41, and transmits the driving force from the auxiliary transmission mechanism 41 to the output shaft 1
02. The brake cover 10
8 is attached to the mission case 107,
The brake mechanism 7 is disposed in front of the brake mechanism 74.
4 is covered.

The output shaft 102 has a pressure plate 1
03 and a plurality of sets of friction plates 104 and brake plates 105 alternately arranged. The front portion of the pressure plate 103 is inserted inside the brake cover 108, and the sliding direction is regulated by the brake cover 108. The pressure plate 103 has a brake cover 108
A spring 110 whose one end is locked is connected to the pressure plate 103 to urge the pressure plate 103 forward. Pressure plate 103 and brake cover 1
08, a ball 109 is provided, which fits into a groove formed in the pressure plate 103 and the brake cover 108. The groove provided in the pressure plate 103 is formed in an arc shape with the output shaft 102 as the center.
By rotating 3, the depth of the groove into which the ball 109 fits becomes shallower. Therefore, by rotating the pressure plate 103, the ball 10
9 is pushed backward. That is, by rotating the pressure plate 103, the pressure plate 103 is slid backward.

Behind the pressure plate 103, a friction plate 104 and a brake plate 10
5 are alternately arranged. Friction plate 10
Reference numeral 4 denotes an outer peripheral portion engaged with the transmission case 107, and the brake plate 105 engaged with the output shaft 102. The friction plate 104 cannot rotate with respect to the transmission case 107, and can slide in the front-rear direction. The brake plate 105 cannot rotate relative to the output shaft 102, and can slide in the front-rear direction. Friction plate 104
The brake plate 105 is configured to be sandwiched between ribs of the pressure plate 103 and the transmission case 107. And pressure plate 1
The friction plate 104 is pressed against the brake plate 105 by sliding 03 backward. As described above, the friction plate 104
Cannot rotate with respect to the transmission case 107, and the brake plate 105 cannot rotate with respect to the output shaft 102. For this reason, by rotating the pressure plate 103, the output shaft 102 is connected to the transmission case 10.
7 is fixed. Thereby, the output shaft 102
And acts as a parking brake.

The pressure plate 103 has a shaft 11
The rear end of the shaft 112 abuts, and an arm 113 is fixed to the front end of the shaft 112. The peripheral part of the pressure plate 103 has a shape in which one portion is cut out, and the rear end of the shaft 112 abuts on the notch. The rear end of the shaft 112 is formed in a semicircular shape, and a flat chord portion is in contact with a notch of the pressure plate 103. From this state, the shaft 11
By rotating 2, the pressure plate 103 comes into contact with the edge of the semicircular portion of the shaft 112, and the pressure plate 103 rotates.

In the above configuration, by rotating the arm 113 fixed to the shaft 112, the shaft 112 is rotated, and the pressure plate 103 is rotated. The arm 113 is connected to a rod 73 connected to the brake pedal 54 via a link. That is, when the brake pedal 53 is depressed, the arm 113 is rotated, and the pressure plate 103 is pressed against the friction plate 104 and the brake plate 105 to apply braking.
As described above, the driving drive take-out portion is provided at the lower portion of the rear transmission case 5, and the driving drive take-out portion is provided with the brake mechanism 7
By operating the brake mechanism 74 with the brake pedal 53, the brake operation mechanism including the brake pedal 54 can be made compact, and the design can be facilitated and the security can be improved.

[0030]

According to the present invention, a crawler tractor is provided for transmitting a driving force of an engine into a transmission case disposed rearward and transmitting a driving force shifted from a traveling drive take-out portion to a traveling device. The crawler tractor brake device is provided in the traveling drive take-out portion below the transmission case, so that the space in the transmission case can be effectively used. Further, the brake device can be arranged at a position close to the brake pedal.

According to a second aspect of the present invention, after the driving force of the engine is shifted by the traveling hydraulic continuously variable transmission, it is transmitted into the transmission case, and the driving force shifted by the traveling drive take-out portion is transmitted to the traveling device. A crawler tractor brake device disposed on a crawler tractor disposed on a crawler tractor for transmitting to a traveling drive take-out unit after returning a swash plate of a traveling hydraulic continuously variable transmission to a neutral position when a brake pedal is depressed. By operating the parking brake, the brake capacity can be reduced, and the brake device can be made compact.

According to a third aspect of the present invention, the crawler tractor transmits the driving force of the engine to the traveling device from the traveling drive take-out portion via the auxiliary transmission provided in the transmission case. The brake device for the crawler tractor is provided in the traveling drive take-out portion below the transmission case and near the auxiliary transmission, so that an interlocking mechanism between the brake device and the transmission can be easily configured.

[Brief description of the drawings]

FIG. 1 is a front perspective view of a crawler tractor.

FIG. 2 is an overall side view.

FIG. 3 is a side view showing an arrangement of an engine, an HST, and a transmission case.

FIG. 4 is a side sectional view showing a configuration inside a rear transmission case.

FIG. 5 is a side view showing a crawler tractor operating device.

FIG. 6 is a side view showing an operation configuration of a brake pedal.

FIG. 7 is a front view of the same.

FIG. 8 is a side view showing an operation configuration of a main shift lever.

FIG. 9 is a diagram showing an interlocking configuration of a brake pedal and a main shift lever.

FIG. 10 is a side sectional view showing a configuration of a brake mechanism.

FIG. 11 is a plan sectional view of the same.

[Explanation of symbols]

 53 Conical Link Mechanism 54 Brake Pedal 55 Main Gear Lever 61 Cam Lever 62 Support Shaft 74 Brake Mechanism 89 Shaft 92 Arm 93 Projection 102 Output Shaft 103 Pressure Plate 104 Friction Plate 105 Brake Plate

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B62D 55/06 B62D 55/06 F term (reference) 3D041 AA09 AA12 AB07 AC15 AC19 AC29 AD42 AE33 AE42

Claims (3)

[Claims] 1. A crawler tractor brake device provided on a crawler tractor for transmitting a driving force of an engine into a transmission case disposed rearward and transmitting a driving force shifted from a traveling drive take-out portion to a traveling device. A crawler tractor brake device provided at a traveling drive take-out portion below a transmission case. 2. A crawler tractor that transmits the driving force of the engine to a transmission case after transmitting the driving force through a hydraulic continuously variable transmission, and transmits the driving force shifted from the traveling drive take-out portion to the traveling device. A crawler tractor brake device that is disposed, and when a brake pedal is depressed,
A brake device for a crawler tractor, wherein a parking brake provided on a traveling drive take-out unit is operated after returning a swash plate of a traveling hydraulic continuously variable transmission to a neutral position. 3. A crawler tractor brake device disposed on a crawler tractor for transmitting a driving force to a traveling device from a traveling drive take-out portion via a subtransmission device disposed in a transmission case. A brake device for a crawler tractor, which is provided in a traveling drive take-out portion below a transmission case and near a subtransmission.