JPS5819969Y2 - Brake and suspension locking devices for hydraulically driven wheel vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a brake and suspension locking device for a hydraulically driven wheel vehicle.

The parking brake, service brake lock, and suspension mechanism of conventional hydraulically driven wheeled vehicles were operated independently or in conjunction with an outrigger mechanism. ,
Complicated operations were required, such as stepping on the brake pedal, turning on the brake lock valve, and turning on the suspension lock valve (in the case of interlocking with the ARA I-IJ gear, operating the outrigger lever).

If these operations were forgotten, there were dangers such as the vehicle body dragging during excavation because the brakes were not working, and the safety ratio worsening because the suspension lock was not working.

The present invention was developed in view of the above circumstances, and its purpose is to automatically release the parking brake, service brake lock, and suspension lock when driving, and to automatically release the parking brake when the vehicle is stopped. The suspension lock is activated, and the service brake is also locked by pressing the brake pedal once, so that excavation work can be started immediately.

Hereinafter, the present invention will be explained with reference to the drawings.

In the drawing, 1 is a pump, 2 is an operating valve, 3 is a brake valve,
4 is a clutch valve, 5 is a travel motor, and the brake valve 3 is composed of a counterbalance valve 3□ and a crossover load safety valve 3□.

These components constitute a running circuit R.

Further, 8 is a shuttle valve, 9 is a foot brake, 10 is a booster, 11 is a brake lock valve, and 12 is a cylinder for operating the brake lock valve 11.

13 is a cylinder for operating the parking brake 14, 15 is a service brake, 6 is a suspension lock valve, and T is a suspension lock cylinder.

Ports 8a and 8b of shuttle valve 8 are connected to lines 16 and 11 between operating valve 2 and brake valve 3 of traveling circuit R via lines 18 and 19.

The port 8c of the shuttle valve 8 is connected to the tank 20, and the port 8d is connected to the cylinder 12.13 via the pilot line 21.
and the pilot port 6a of the suspension lock Palflo.

The cylinder port 9a of the mask cylinder of the foot brake 9 is connected to the brake lock valve 1 via the booster 10.
The port 11b is connected to the pipe line 21, 2.
Brake cylinder 1 of the service brake 15 via 2
5a and 15b, and these constitute a service brake circuit S.

Ports 6a and 6b of the suspension lock valve 6 are connected to the tank 20, and the old ports 6c and 6ci are connected to the tank 20.
is connected to the suspension lock cylinder 1 via conduits 23 and 24.

The brake lock valve 11 has a brake operating pressure holding position A with a check valve C and a brake operating pressure release position B, and is controlled by a cylinder 12 operated by pilot pressure from a travel circuit R.

The holding position A of the brake lock valve 11 is such that the brake hydraulic fluid compressed by the pedal is in the brake cylinder 15.
Check valve C prevents leakage from a and 15b to maintain the brake state when the vehicle is parked.The release position B is the brake operating position when the vehicle is running, and the brake hydraulic fluid compressed by the pedal. Since there is no check valve C, it is released from the brake cylinders 15a, jl, and 5b by releasing the pedal.

The above brake control state is switched by the cylinder 12.

In the cylinder 12, the pilot pressure overcomes the spring 12b to position the release position B of the brake lock valve 11 on the port side, and the spring 12b positions the holding position A on the port side when no pilot pressure is applied.

Next, the operation will be explained.

When the vehicle is traveling, the oil pressure in the traveling circuit R increases, and the high pressure side is taken out by the shuttle valve 8, and this pilot pressure is used to operate the cylinder 13 to release the parking brake 14, and the pilot pressure is used to operate the cylinder 12. The brake lock valve 11 is switched to release the braking by the service brake 15, and the suspension lock valve 6 is further actuated by pilot pressure to release the suspension lock by the suspension lock cylinder T.

In this case, when the clutch valve 4 is disengaged during gear shifting while driving or when the vehicle is dismounted, the pressure in the driving circuit decreases, and there is a possibility that the parking and service brakes 14, 15 and the suspension lock cylinder 1 will operate, so the pressure inside the brake valve 3 will decrease. The switching pressure of the counter balance valve 31 is the switching pressure of the shuttle valve 8, the parking brake 14, the brake lock valve 11,
The pressure is set higher than the release pressure of the suspension lock valve 6 to prevent these from operating while driving.

In the past, the brakes would not work even when starting due to calluses14.
15 and the suspension lock is released, and then the counter balance valve 31 is switched and the motor 5 is driven, so that the vehicle does not travel with the suspension locked by the brake 14, 15 or the suspension lock cylinder 1.

When the operation valve 2 is returned to neutral when stopped, the pilot pressure is eliminated, so the parking brake 14 is put into the braking state by the biasing force of the spring 13b in the cylinder 13, and the parking brake 14 is braked by the biasing force of the spring 13b in the cylinder 13. The lock valve 11 reaches the holding position A on the port side, and the service brake 15 becomes available for braking.Furthermore, the suspension lock valve 6 is switched and returns to the lock position, and the suspension lock cylinder 1 is locked.

Depress the brake pedal on the broken foot brake 9 and transfer the brake hydraulic pressure from the mask cylinder to brake cylinder 1.
5a and 15b, the brake hydraulic pressure is locked by the check valve C, and when the hood brake 9 is depressed once to maintain the brake state, the service brake 15 is also locked.

As described in detail above, the present invention includes a shuttle valve 8 that takes out the high pressure side hydraulic pressure generated in the traveling circuit R during driving, and a pilot pressure from the shuttle valve 8 that operates against the spring 13b to release the parking brake 14. A foot brake 9 is provided in the circuit S of the service brake 15 and supplies hydraulic pressure to the brake cylinders 15a and 15b of the service brake 15, and a foot brake 9 is provided in the circuit S of the service brake 15 and operates on the side. The brake lock valve 11 has a holding position A having a check valve C that restricts the flow of oil from the brake 9 only to the brake cylinders 15a and 15b, and a release position B that releases the brake hydraulic pressure in the brake cylinders 15a and 15b.
, the spring 12b is activated by the pilot pressure from the shuttle valve 8.
The cylinder 12 operates against the pressure and switches the brake lock valve 11 from the holding position A to the release position B, and the cylinder 12 locks and releases the lock of the suspension lock cylinder 1, and also controls the pilot pressure from the shuttle valve 8. This is a brake and suspension lock device for a hydraulically driven wheel type vehicle, characterized in that it is equipped with a suspension lock valve 6 that performs a lock release operation from an I.

Therefore, when traveling, the high pressure side of the travel circuit R is taken out by the shuttle valve 8 due to an increase in the oil pressure of the travel circuit R, and this high pilot pressure causes the cylinder 13 to spring 13b/
The released pilot pressure operates against the spring 12b and positions the brake lock valve 11 at the port-side release position B. The braking by the service brake 15 is released, and furthermore, the pilot pressure switches the suspension lock valve 6 to release the suspension lock by the suspension lock cylinder γ, so when driving, the parking brake, service brake lock, and suspension are automatically activated. The lock will be released.

When the vehicle is stopped, the pilot pressure disappears, so the parking brake 14 is applied by the biasing force of the spring 13b in the cylinder 13.
Suspension lock valve 6
When the vehicle stops, the parking brake and suspension lock are activated automatically so that the suspension is locked by the suspension cylinder 1.

Also, when the brake pedal of the foot brake 9 is depressed to send brake hydraulic pressure to the brake cylinders 15a and 15b to stop the vehicle from traveling, the pilot pressure is released and the brake lock valve 11 returns to the force of the spring 12b, locking the brake hydraulic pressure and automatically The brake state can be maintained, and the service brake can be locked and the excavation work can be started immediately by depressing the brake pedal once.

[Brief explanation of the drawing]

The drawing is a hydraulic circuit diagram of an embodiment of the present invention. 8 is a shuttle valve, 13.12 is a cylinder, 11 is a half frame lock valve, and 6 is a suspension lock valve.

Claims (1)

[Scope of Claim for Utility Model Registration] A shuttle valve 8 that takes out the high pressure side hydraulic pressure generated in the traveling circuit R during driving, and a pilot pressure from the shuttle valve 8 that operates against the spring 13b to release the parking brake 14. The actuated cylinder 13 and the brake cylinder 15a of the service brake 15 are provided in the circuit S of the service brake 15. A foot brake 9 supplies hydraulic pressure to the brake cylinder 15b, and a circuit S of the service brake 15 connects the foot brake 9 to the brake cylinder 15a. The holding position A and the brake cylinder 15a have a check valve C that allows oil to flow only to the 15b side. The brake lock valve 11 has a release position B that releases the brake hydraulic pressure in the brake lock valve 15b, and the brake lock valve 11 operates against the spring 12b by pilot pressure from the shuttle valve 8 to shift the brake lock valve 11 from the holding position A to the release position B. A hydraulic system characterized by comprising a cylinder 12 for switching positions, a suspension lock valve 6 for locking and releasing the lock of the suspension lock cylinder T, and for releasing the lock by biloft pressure from the shuttle valve 8. Brake and suspension locking devices for drive wheel vehicles.