JPS6323218Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field This invention relates to a hydraulic circuit for an oil clutch vehicle equipped with power steering.

Prior Art FIG. 1 shows a conventional hydraulic circuit in a forklift truck equipped with power steering and an oil clutch. Engine (not shown)
The oil supplied from the oil tank 2 by the oil pump 1 driven by
minute) is supplied to the flow divider valve 6 through the brake valve 5, and a portion is returned to the oil tank 2 through the oil filter 7. Further, oil is also supplied from the control valve 4 to the lift cylinder 8 and the tail cylinder 9 by switching the valve.

The oil supplied to the flow divider valve 6 is used for the clutch booster 10 (2.3/min) and the steering valve 1 that controls the power cylinder 11.
2 (9.2/min). The oil for the clutch booster 10 (2.3/min) passes through the clutch booster 10 and is directly returned to the oil tank 2 via a pipe 13, and only the oil for the steering valve 12 (9.2/min) is returned to the oil clutch 15 via a pipe 14. Supplied. The oil (9.2/min) supplied to the oil clutch 15 is distributed by a distribution valve 16 installed inside the oil clutch 15.
The nozzle 16a sprays oil onto the clutch disk 17 for cooling (1/min), and the nozzle 16a sprays oil into the clutch disk 17 for cooling (8.2/min).

In order to prevent the oil clutch 15 from being filled with the oil sprayed from the nozzle 16a onto the clutch disk 17, the flow rate of the suction oil cannot be reduced below 8.2/min. Therefore, in the conventional hydraulic circuit configuration, unless the capacity of the oil pump 1 and the engine that drives it are increased, the amount of oil for cooling the oil clutch 15 can be reduced by 1/2.
It was not possible to increase the amount by more than 10 minutes, and troubles due to insufficient cooling sometimes occurred when operating the clutch in a half-way position. Further, the distribution valve 16 sprays oil onto the clutch disk 17, and at the same time sucks up oil accumulated in the oil clutch 15 by negative pressure and collects it in the tank 2. However, when the oil is in a low temperature state, the oil Due to the increased viscosity, sufficient negative pressure could not be obtained, the amount of oil sucked up changed, and the amount of oil sprayed onto the clutch disk was also affected, making it impossible to obtain stable cooling performance.

Purpose This invention was made to eliminate the above-mentioned conventional defects, and its purpose is to increase the amount of oil for cooling the oil clutch without increasing the capacity of the oil pump and the engine that drives it. To provide a hydraulic circuit for an oil clutch vehicle that can prevent insufficient cooling of the clutch affected by oil temperature.

Embodiment An embodiment embodying this invention will be described below with reference to FIG.

In the hydraulic circuit of this embodiment, an oil suction valve 20 is provided in the oil clutch 15, a cooling oil injection nozzle 21 is provided, the steering valve 12 and the suction valve 20 are connected by a pipe 14, and the clutch booster 10 and It differs from conventional hydraulic circuits in that it is connected to a cooling injection nozzle 21 through a pipe 22.

Therefore, the oil used in the steering valve 12 is used only for sucking oil into the oil clutch 15, and the oil used in the clutch booster 10 is used only for cooling the oil clutch 15.

Next, the operation of the hydraulic circuit configured as described above will be explained.

The oil supplied from the oil tank 2 by the oil pump 1 is supplied by a flow divider (not shown) in the control valve 4 at a constant flow rate (1.5/min) to the flow divider valve 6 through the brake valve 5. Ru. The oil supplied to the flow divider valve 6 is divided into the clutch booster 10 (2.3/min) and the steering valve 12 (9.2/min). The oil diverted to the clutch booster 10 is sprayed onto the clutch disc 17 via a pipe 22 as cooling oil (2.3/min) by a cooling oil injection nozzle 21.

Therefore, more than twice as much cooling oil is sprayed onto the clutch disc 17 as compared to the conventional case. Therefore, the cooling capacity of the oil clutch 15 is increased, and troubles due to insufficient cooling when operating the clutch half-way are prevented.

Note that this invention is not limited to the above-mentioned embodiments, and can be arbitrarily modified without departing from the spirit of this invention.

Effects of the invention As detailed above, this invention differs from the conventional ones by providing a suction valve and a cooling oil injection nozzle instead of providing a distribution valve with a complicated structure that has an oil suction function and an oil injection function. Therefore, the structure is simple, and if a distribution valve is used in the past, the amount of oil for cooling and suction changes depending on the temperature, but this invention does not use a distribution valve, so it is possible to use a cooling oil injection nozzle. The amount of oil sprayed onto the clutch disc is not affected by oil temperature, providing oil clutch cooling performance. Moreover, it is possible to increase the amount of oil for cooling the oil clutch without increasing the capacity of the oil pump and the engine that drives it, and this has the excellent effect of preventing troubles due to insufficient cooling of the clutch.

[Brief explanation of the drawing]

FIG. 1 is a hydraulic circuit diagram of a conventional oil clutch vehicle, and FIG. 2 is a hydraulic circuit diagram showing an embodiment of this invention. Oil pump...1, Flow divider valve...
...6, Clutch booster...10, Steering valve...12, Piping...13, 14, 22, Oil clutch...15, Oil suction valve...2
0. Cooling oil injection nozzle...21.

Claims (1)

[Scope of utility model registration request] The oil supplied from the oil pump to the power cylinder and clutch booster is returned to the tank through a cooling system within the oil clutch, and the power cylinder is connected to an oil suction valve provided within the oil clutch. A hydraulic circuit for an oil clutch vehicle in which piping and piping connecting the clutch booster and a cooling injection nozzle provided in the oil clutch are each independently provided.