초록 ▼

The present invention is a crawler device for a crawler type vehicle, which lowers the vehicle height, decreases the vehicle width, and exhibits superior stability during operation. For this purpose, in a crawler type vehicle having, on right and left sides of either one of front or rear portion, or

The present invention is a crawler device for a crawler type vehicle, which lowers the vehicle height, decreases the vehicle width, and exhibits superior stability during operation. For this purpose, in a crawler type vehicle having, on right and left sides of either one of front or rear portion, or both of the front and rear portions of a vehicle body, crawler devices each having a sprocket, an idler disposed on a truck frame, and a crawler belt passed through the sprocket and the idler, the crawler device can include a front end link coupled to a forward part of the truck frame by a pin at a lower end portion thereof and to the side of said vehicle body by a pin at the upper end portion thereof, and can include a rear end link coupled to a rearward part of the truck frame by a pin at the lower end portion thereof and to the side of the vehicle body at a position behind the front end link by a pin at the upper end portion thereof.

대표청구항 ▼

The present invention is a crawler device for a crawler type vehicle, which lowers the vehicle height, decreases the vehicle width, and exhibits superior stability during operation. For this purpose, in a crawler type vehicle having, on right and left sides of either one of front or rear portion, or

The present invention is a crawler device for a crawler type vehicle, which lowers the vehicle height, decreases the vehicle width, and exhibits superior stability during operation. For this purpose, in a crawler type vehicle having, on right and left sides of either one of front or rear portion, or both of the front and rear portions of a vehicle body, crawler devices each having a sprocket, an idler disposed on a truck frame, and a crawler belt passed through the sprocket and the idler, the crawler device can include a front end link coupled to a forward part of the truck frame by a pin at a lower end portion thereof and to the side of said vehicle body by a pin at the upper end portion thereof, and can include a rear end link coupled to a rearward part of the truck frame by a pin at the lower end portion thereof and to the side of the vehicle body at a position behind the front end link by a pin at the upper end portion thereof. 1. Pressure-control valve with a first control piston (1), which is disposed between a first pressure chamber (6), which adjoins the first control piston (1) and is connected to at least one working line (A, B), and a second pressure chamber (7), which adjoins the first control piston (1) and is pr loaded against a stop (3) by a first preloading spring (4), and a throttle (8) connecting the first pressure chamber (6) and the second pressure chamber (7), wherein the second pressure chamber (7) is connected to a second control piston 11, which is preloaded by a second preloading spring (17) and which, when a predetermined pressure in the second pressure chamber (7) is exceeded, is displaced to an extent such that a control edge (12) of the second control piston (11) clears a connection of the second pressure chamber (7) to a hydraulic fluid discharge point (23), characterised in that the first control piston (1) comprises a control edge (2) which connects an actuating pressure line (5) to the hydraulic fluid discharge point (23) when the first control piston (1) is displaced against the first preloading spring (4), the throttle (8) being disposed in a bore (9) in the first control piston (1); and an actuator (15), which is activated by a control signal, act on the second control piston (11) against the second preloading spring (17), said second control piston (11) having a maximum force exerted thereon and said first control piston being lifted off from said stop (3) when no force is provided by said actuator (15) to thereby produce a maximum pressure in working lines (A, B). 2. Press re-control valve according to claim 1, characterised in that control edge (12) of the second control piston (11) clears a discharge point having a cross section greater than that of the throttle (8). 3. Pressure-control valve according to claim 1 or 2, characterised in that the second control piston (11) is a differential area piston comprising two differeing areas (19, 20) which act in oppiosoition to one another and on which the pressure from the second pressure chamber (7) acts. 4. Pressure-control valve according to claim 1, characterised in that the actuator (15) is a proportional magnet having an electric current flowing therough it as control signal. 5. Press re-control valve according to claim 1, characterised in that, adjoining the control edge (2), the first control piston (1) comprises at the outer circumference at least one recess (24) via which hydraulic fluid can run off out of the actuating pressure line (5) to the hydraulic fluid dishcarge point 23). 6. Pressure-control valve according to claim 5, characterised in that the recess (24) is not connected either to the first pressure chamber (6) or the second pressure chamber (7). 7. Pressre-cotnrol valve according to claim 1, characterised in that the first preloacding spring (4) is supported against a first threaded pin (10), and a minimum regulation pressure in the working me (A, B) can be set by the latter upon maximum activation of the actuator (15). 8. Pressure-control valve according to claim 1, characterised in that the second preloading spring (17) is supported against a second threaded pin (18), and the maximum regualtion pressure in the working line (A, B) can be set at the latter when the actuator (15) is inactive. 9. Pressure-control valve according to claim 1, characterised in that a shuttle valve piston (21) is disposed between the first pressure chamber (6) and two said working lines (A, B), which piston is slidably disposed said bore (9) in the first control piston (1) of the pressure-control valve and can be displaced between two end positions through the action of a respective higher pressure of a hydraulic fluid in one of the two working lines (A, B), wherein the shuttle valve piston (21) comprises an inner through-bore (22) which extends over its entire length and via which the higher pressure is admitted to the first pressure chamber (6) when the shuttle valv e piston (21) is on one of two end positions thereof.