JPS6337522Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure oil device for securing a pressure oil source used for hydraulic control of hydraulic machines such as water turbines and pump water turbines.

In general, conventional hydraulic equipment for hydraulic machines does not have a special function for draining control oil, but instead uses a method such as bringing in a filtering device specifically designed for oil draining to drain the oil after it has been used for a certain period of time. The cleanliness of the control oil was maintained. FIG. 1 shows an example of a conventional pressure oil device. Oil discharged from the pressure oil pump 3 from the oil collection tank 1 through the suction strainer 2 is supplied to the pressure oil tank 6 by the unloader valve 5 operated by the pilot valve 4, or is supplied to the oil collection tank 1. be returned. (FIG. 1 shows the unloaded state.) 7 is a check valve, and 8 is a hydraulic switching valve for operating the servo motor 9.

In normal operation, the pressure oil pump 3 is operated continuously, and the pressure oil in the pressure oil tank 6 is consumed by the servo motor 9, so that the pilot valve 4 is switched due to changes in the oil pressure in the pressure oil tank 6, and the unloader valve 5 is switched. The pressure oil tank 6 is operated in an on-load state, that is, a state in which oil is supplied to the pressure oil tank, or in an unload state, that is, in a state in which the entire amount of oil discharged from the pressure oil pump is returned to the oil collection tank.
The mechanism controls the hydraulic pressure to a nearly constant pressure.

The suction strainer 2 provided on the suction side of the pressure oil pump 3 is used to prevent foreign matter from entering the pressure oil pump 3 and damaging the pressure oil pump 3. The target is If the suction strainer 2 is too finely woven, the suction head of the pump will change in a short period of time due to clogging, making it impossible to continue operating the pressure oil pump 3, which is undesirable.

On the other hand, for example, the pilot valve 4 has a built-in movable valve with a small gap, and thus requires oil of higher purity than the pressure oil pump 3. For this reason, as mentioned above, conventionally, in order to maintain the cleanliness of the control oil, the operation of the pressure oil equipment is stopped after a certain period of use, and a special oil filtration equipment (not shown) is brought in to perform overwork. The need arose. However, such an oil filtration method has problems such as the cost of the oil filtration device, the hassle of overwork, and the suspension of operation of the pressure oil device.

The present invention was developed in view of the above circumstances, and it allows continuous operation of the hydraulic oil equipment without stopping its operation.
Moreover, it is an object of the present invention to provide a pressure oil device that can drain oil with sufficient precision for operating pilot valves and the like.

An embodiment of the present invention will be described below with reference to FIG. Components that are the same as those in FIG. 1 are designated by the same reference numerals and their explanations will be omitted. The unloader drain oil main pipe 14 is branched, and the main pipe 14 is provided with a variable adjustment throttle valve 10.
and a line filter 13 are provided.

Next, the action will be explained.

In the unloaded state, oil flows from the oil collection tank 1 through the suction strainer 2, is lifted by the pressure oil pump 3, and flows to the oil drain side of the unloader valve 5.
Since the variable adjustment throttle valve 10 is provided and throttled, a certain amount of oil flows from the primary side of the variable adjustment throttle valve 10 to a branched oil drain pipe 15. This divided oil passes through a two-way tank 11, an orifice 12, and a line filter 13 and is returned to the oil collection tank. In this way, in the unloaded state, a certain amount of oil in the oil collection tank 1 flows through the line filter 13, so that the oil in the oil collection tank 1 is kept clean. In addition, even when the entire pressure oil equipment is in operation,
By temporarily closing the two-way socket 11 provided in the branch pipe 15, the line filter 13
Elements can be easily replaced. In addition, compared to a system in which a variable adjustment throttle valve 10 is installed and a line filter is inserted directly into the main pipe line 14 of the oil drain pipe in order to divert waste oil, the capacity required for the pressure oil equipment can be reduced without installing a line filter with a capacity larger than the required capacity. You can select a line filter that is suitable for your needs.

As mentioned above, according to the present invention, it is possible to easily remove foreign substances inside the oil that cause malfunction and wear of the pressure oil equipment equipment, improve the reliability of the pressure oil equipment itself, and at the same time improve the reliability of the pressure oil. It is thus possible to significantly improve the reliability of the controlled equipment.

Moreover, the oil can be drained without stopping the operation of the pressure oil device itself.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of a conventional hydraulic oil system for a hydraulic machine, and FIG. 2 is a schematic diagram showing an embodiment of the present invention. 1... Oil collection tank, 2... Suction strainer, 3... Pressure oil pump, 4... Pilot valve, 5... Unloader valve, 6... Pressure oil tank, 7... Check valve, 8... ... Hydraulic switching valve, 9 ... Servo motor, 10 ... Variable adjustment throttle valve, 11 ...
Two-way lock, 12... Orifice, 13... Line filter, 14... Unloader valve oil drain main line, 15... Unloader valve branch line.

Claims (1)

[Scope of utility model registration request] An oil collection tank that stores oil, a pressure oil tank that is installed separately from this oil collection tank and stores pressurized oil,
A pressure oil pump that sucks oil in the oil collection tank and sends it to the pressure oil tank, and is installed in the system between the discharge side of this pressure oil pump and the pressure oil tank, and the downstream flow path is connected to the pressure oil tank side. or a selectable unloader valve on the oil collection tank side, and an unloader valve oil drain main pipe line leading from the unloader valve to the oil collection tank;
A pilot for operating the unloader valve that switches the downstream flow path of the unloader valve to the pressure oil tank side when the pressure of the pressure oil tank is lower than a predetermined value, and to the oil collection tank side when the pressure of the pressure oil tank is higher than a predetermined value. In a hydraulic oil system for a hydraulic machine comprising a valve, an unloader valve branch pipe branching from the unloader valve main drain oil pipe line and reaching an oil collection tank, and a two-way cock installed on the unloader branch pipe line. , a line filter installed on the unloader branch pipe between this two-way tank and the oil collection tank, and a variable line filter installed on the unloader valve oil drain main pipe on the downstream side of the branch point with the unloader branch pipe. A pressure oil device for a hydraulic machine, characterized by comprising an adjustment throttle valve.