JPS6143992Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an oil rotary vacuum pump, and more particularly to an oil rotary vacuum pump having a function of purifying oil in an oil tank using a filter.

[Technical background of the invention and its problems]

Oil rotary vacuum pumps are usually constructed by installing a cylinder in which an eccentrically rotating rotor is housed in an oil tank.In order to improve the lubrication, vacuum degree, and pumping speed in the cylinder, the oil in the oil tank is The air flows into the cylinder, and the rotation of the rotor evacuates the vacuum container.

In the above-mentioned pump, the gas to be exhausted passes through the oil tank, so if the exhaust gas contains harmful substances, these harmful substances are not discharged outside the pump and are absorbed into the oil. It gets mixed in. Therefore, conventionally, the oil is purified using a filter and only the purified oil is supplied into the cylinder to prevent contamination inside the cylinder.

However, in the case of such a pump, when replacing the filter element due to functional deterioration, it is necessary to stop the supply of oil to the cylinder, and the pump must be stopped to prevent seizure, etc. inside the cylinder. The problem is that it has to be done. In addition, due to clogging of the above elements, etc.
This has the disadvantage that if oil is no longer supplied into the cylinder or if the amount of oil supplied decreases, the pump may suffer damage such as seizure.

[Purpose of invention]

This idea was made in view of the above points,
The object of the present invention is to provide an oil rotary vacuum pump that can constantly supply oil into a cylinder without having to stop the pump even when replacing a filter element.

[Summary of the idea]

In order to achieve the above object, the oil rotary vacuum pump of the present invention is provided with a cylinder in which an eccentrically rotating rotor is housed in an oil tank and whose one side is sealed by a side wall of the pump, and the oil in the oil tank is passed through a filter and returned to the oil tank. In an oil rotary vacuum pump, the end of the communication pipe through which the purified oil flows is provided in an oil rotary vacuum pump, which performs evacuation by rotation of the rotor and purifies the oil in the oil tank by the filter. , an oil supply hole is provided in the side wall of the pump, one end of which is connected to a communication hole that opens into the oil in the oil tank, and which branches from the communication hole and opens into the cylinder, and is connected to the filter of the communication pipe. A stop valve is interposed between each of the oil tanks, and during normal operation, purified oil flowing through the communication pipe is supplied into the cylinder from the oil supply hole, and when the filter is replaced, each of the above By closing the stop valve, oil in the oil tank is supplied into the cylinder through the communication hole and the oil supply hole. Therefore, there is no need to stop the pump even when replacing the filter.

[Example of idea]

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2.

FIGS. 1 and 2 show an embodiment in which the present invention is applied to a rotary vane type oil rotary vacuum pump, in which a cylinder 2 is fixed to the inside of one side of an oil tank 1. A pump side surface 3 is fixed to the pump so as to close the other side surface. A rotor 4 is arranged eccentrically inside the cylinder 2 so that a part of the rotor 4 is always in contact with the inner circumferential surface of the cylinder 2, and is attached to the rotor 4 so as to pass through the center axis thereof. The drive shaft 5 is rotatably supported by bearings 6, 6 provided on the side surface of the oil tank 1 and the pump side surface 3, respectively, and has one end extending outside through the side surface of the oil tank 1 (not shown). Connected to a drive source such as a motor. Further, rotary blades 8, 8 are provided at diametrically symmetrical positions of the rotor 4, and are biased in the radial direction by a spring 7.
It is designed to be in close contact with the inner circumferential surface of. Furthermore, an intake passage 9 is provided on the suction side of the cylinder 2 and extends to the outside through the oil tank 1, and on the discharge side, an intake passage 9 is opened into the oil tank 1 and an exhaust valve 10 such as a check valve is provided at the open end. A fitted exhaust passage 11 is provided.

Further, a communication pipe 12 is connected to the lower part of the oil tank 1, and a stop valve 13,
An oil pump 14, a filter 16 in which an element 15 is disposed, and a stop valve 17 are provided in this order. The end of the communication pipe 12 is
It penetrates through the oil tank 1 and is connected to a communication hole 18 provided on the upper surface of the pump side surface 3.
The end of the cylinder 1 opens into the oil inside the oil tank 1, and an oil supply hole 19 is provided which branches from the middle of the communication hole 18 and opens into the cylinder 2. A pressure gauge 20 is connected to a pipe branching from between the oil pump 14 and the filter 16, and an exhaust port 21 is provided on the upper surface of the oil tank 1.

When evacuation is performed in this embodiment, the rotor 4 is rotated by a drive source connected to the drive shaft 5, and the internal gas of the vacuum container or the like is sucked through the intake passage 9 and exhausted from the exhaust passage 11. This exhaust gas is then exhausted to the outside from the exhaust port 21. At this time, if the gas contains harmful substances, some of the harmful substances will be mixed into the oil, so the oil in the oil tank 1 is sent to the filter 16 by operating the oil pump 14. , this filter 16
After the harmful substances are removed by the element 15 inside the oil tank 1, the oil is returned to the oil tank 1 through the communication pipe 12 and the communication hole 18.

In addition, since the inside of the cylinder 2 becomes a vacuum during pump operation, the purified oil flows into the cylinder 2 through the oil supply hole 19 due to the pressure difference between the inside of the cylinder 2 and the communication hole 18, and the oil flows into the cylinder 2 through the oil supply hole 19. Made to enhance lubrication and airtightness. At this time, in this embodiment, the flow rate flowing through the communication pipe 12 by the oil pump is made larger than the amount flowing into the cylinder 2 from the oil supply hole 19, and the diameter of the oil supply hole 19 is made smaller than the diameter of the communication hole 18. Therefore, all the oil flowing into the cylinder 2 is purified oil.

When the function of the element 15 in the filter 16 deteriorates due to harmful substances, the amount of oil passing through the element 15 decreases and the pressure gauge 20 shows a higher pressure value than usual, so the stop valves 13 and 17 are closed and the oil Stop the pump 14 and replace the element 15. At this time, the oil in oil tank 1 is
Since the oil flows into the cylinder 2 through the communication hole 18 and the oil supply hole 19, there is no need to stop the pump, and it is possible to prevent the occurrence of seizure and poor vacuum degree.

[Effect of idea]

As described above, the oil rotary vacuum pump according to the present invention connects the end of the communication pipe through which purified oil flows to the communication hole provided in the side wall of the pump and having one end opened in the oil, and It is configured with an oil supply hole that branches out from the hole and opens into the cylinder.
During oil purification, oil from the communication pipe is sent into the cylinder through the oil supply hole, and when oil purification is stopped, the oil in the oil tank is sent from the communication hole into the cylinder through the oil supply hole. As a result, purified oil is normally supplied into the cylinder, thereby preventing contamination within the cylinder, and oil can always be supplied into the cylinder even when the filter element is replaced. As a result, the pump does not seize due to element clogging, and there is no need to stop the pump when replacing the element.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, with FIG. 1 being a front sectional view and FIG. 2 being a side sectional view. 1... Oil tank, 2... Cylinder, 3... Pump side wall, 4... Rotor, 5... Drive shaft, 6... Bearing,
7... Spring, 8... Rotating blade, 9... Intake passage, 1
0... Exhaust valve, 11... Exhaust passage, 12... Communication pipe, 13, 17... Stop valve, 14... Oil pump, 15... Element, 16... Filter, 1
8...Communication hole, 19...Oil supply hole, 20...Pressure gauge, 21...Exhaust port.

Claims (1)

[Scope of utility model registration request] A cylinder is provided in the oil tank, which houses a rotor that rotates eccentrically, and one side of which is sealed by the pump side wall.
An oil rotary vacuum pump is provided with a communication pipe for returning the oil in the oil tank to the oil tank via a filter, and the oil in the oil tank is purified by the filter by evacuation by the rotation of the rotor, The end of the communication pipe through which the purified oil flows is connected to a communication hole provided in the side wall of the pump, one end of which opens into the oil in the oil tank, and branches from the communication hole and opens into the cylinder. An oil rotary vacuum pump characterized in that an oil supply hole is provided, and a stop valve is interposed between the filter of the communication pipe and the oil tank.