JPH084988A - Method of depressurizing intermittent lubricating system - Google Patents

Abstract

PURPOSE:To provide a depressurizing method which can surely depressurize an intermittent lubricating system and which can supply a specific volume of lubricant. CONSTITUTION:A gear pump 7 driven by a motor 6 and a selector valve 10 are provided between a lubricant storage chamber 1a and a discharge passage 20, and accordingly, the pressure of the lubricant is increased by normally rotating the gear pump 7 by the motor 6. Due to the increased pressure, the pressure limiting and depressurizing spool 9 is moved so that the selector valve 10 communicates the discharge port 7, and a passage 17 and a discharge passage 20 with one another so as to limit the pressure. The motor 6 instantly changes its rotating direction into a reverse direction, just after the stopping of the rotation. Thus obtained sucking pressure allows the spool to move back to its original position, and accordingly, the discharge passage 20 is communicated with the communication passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a depressurizing method for promptly removing residual pressure of lubricating oil in a pipe in an intermittent greasing system for intermittently supplying a lubricant to a lubrication necessary portion of various equipment.

[0002]

2. Description of the Related Art A system for intermittently supplying a lubricant to a rotating portion or a sliding portion of various equipment is such that a lubricating oil in a storage chamber is sent to a single pipe type piston distributor by a lubrication pump and a fixed amount of lubrication is carried out by the distributor. It is designed to supply oil to the lubrication point.

By the way, when a viscous material such as grease is used as a lubricant and the lubrication is carried out in an intermittent greasing system, the viscosity due to the consistency may cause the operation of the system to be disturbed.

That is, although the single pipe type piston distributor in the intermittent lubrication system is not shown in the drawing, the oil supply pump is installed in the main pipe with a certain amount of lubricating oil contained in the oil chamber above the piston formed in the distributor. When a new oil is started to be sent to the piston, the piston moves upward, the oil in the oil chamber is sent to the lubrication point, and when the pressure in the main pipe decreases due to the depressurizing action, the piston returns to the initial position, at which time the oil Since the structure is such that new oil enters the chamber, and because of that structure, a greasing operation is required after the discharge operation, the system pressure must be increased and depressurized without interruption.

Conventionally, the depressurizing mechanism of the system is generally performed by releasing the residual pressure from a closed circuit by a switching valve or the like provided in the circuit of the system.
Further, the switching driving force of the switching valve and the like depends only on the return force of the spring.

[0006]

However, when the lubricating oil is grease, the pipe resistance due to its viscosity is much higher than that of oil, so when the system is large or the viscosity of the grease is affected by the ambient temperature. If it becomes higher, the switching valve may not be switched only by the spring force of the depressurizing mechanism, the depressurizing operation may not be performed smoothly, and the residual pressure hinders the greasing operation of the distributor, hindering the quantitative distribution. There is a problem of coming.

SUMMARY OF THE INVENTION An object of the present invention is to provide a depressurizing method for an intermittent greasing system which is capable of forcibly performing depressurizing operation to surely cause a grease storage operation of a distributor.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention promptly reverses the motor after stopping the driving of the pump by the normal rotation of the motor, and switches by the suction force by the reverse rotation of the gear pump. This is a structure that assists the depressurizing operation that connects the discharge passage of the valve and the storage chamber.

[0009]

[Function] When the gear pump is driven by the normal rotation of the motor, the lubricating oil in the storage chamber is sent to the discharge port and the pressure rises,
The movement of the spool of the switching valve causes the discharge port and the discharge passage to communicate with each other by the movement due to this pressure increase, the lubricating oil is supplied toward the distributor, and when the pressure of the lubricating oil further rises due to the completion of the discharging operation of the distributor, the spool moves. Then, the discharge passage is communicated with the storage chamber and the discharge port, and the lubricating oil from the gear pump is returned to the storage chamber.

When the motor is stopped in this state, the spool is returned to its original position due to the stop of the discharge of the gear pump, and the discharge passage and the storage chamber are communicated with each other to reduce the pressure in the distributor.

At this time, the motor reversely rotates for a fixed time instantly at the same time when the normal rotation is stopped, and the lubricating oil in the discharge passage is forcibly returned to the storage chamber by the suction force by the reverse rotation of the gear pump. , Promptly and surely assists the return of the spool to the depressurized position, and depressurizes the distributor.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the intermittent greasing system comprises a greasing and depressurizing mechanism 2 for intermittently pumping the lubricating oil in the storage container 1 by a pump, and a piston connected to this mechanism 2 through a pipe 3. Type distributor 4, and the greasing and depressurizing mechanism 2 is a distributor 4
The lubricating oil is supplied to and depressurized.

The greasing / depressurizing mechanism 2 has a gear pump 7 driven by a motor 6 capable of rotating in the pump body 5 in the forward and reverse directions.
A push button spool 8 and a switching valve 10 provided with a pressure suppression / depressurization spool 9 are incorporated.
The storage container 1 for the lubricating oil is mounted on the upper side of the supply side plate 11, and the discharge side plate 12 fixed to the lower portion of the pump body 5 is provided with the discharge port joint 13.

As shown in FIG. 2, the suction port 1 of the gear pump 7 is
4 communicates with the chamber 15 provided in the pump body 5 and the storage chamber 1a in the storage container 1 via the passage 16 of the supply side plate 11, and the discharge port 17 of the pump 7 is a cylinder hole of the switching valve 10. It communicates with the inside of 18.

The cylinder hole 18 in the switching valve 10 communicates with the chamber 15 through the passage 19, and also communicates with the discharge port joint 13 through the discharge passage 20 and the passage 21 of the discharge side plate 12, and the cylinder hole 18 is formed. Push button spool 8 on the right side of FIG. 1 and pressure control and depressurization spool 9 on the left side of FIG.
Has been inserted.

As shown in FIG. 3A, the push button spool 8
Has a conical taper cam portion 22 on the outer peripheral surface on the base end side and a small diameter shaft 23 on the front end side, and is inserted into the cylinder hole 18 so as to be movable in the axial direction. The holder 24 is fixed to the outer side of the holder 24 so that the base end portion protrudes outside the holder 24 so that the pushing operation can be performed.

A limit switch 25 is incorporated in the holder 24, and when the push button spool 8 is pushed in, the switch 25 is pushed by the taper cam portion 22 so that the motor 6 is energized for normal rotation. .

Further, as shown in FIG. 3 (B), the pressure suppressing / depressurizing spool 9 has a small diameter portion 26 on the outer peripheral surface on the base end side, and a spring 27 moves it into the cylinder hole 18 to the original position shown in FIG. When the spool 9 is in the original position, the base end surface of the spool 9 and the tip of the small diameter shaft 23 of the push button spool 8 come into contact with each other, and the push button spool 8 is pushed back. In position.

As shown in FIG. 1, when the pressure suppressing / depressurizing spool 9 is in the original position, the proximal end side head portion 28 blocks the communication between the discharge port 17 and the discharge passage 20, and the small diameter portion 26 discharges the passage 19 to the discharge passage 19. The passage 20 is communicated, and the inside of the pipe 3 is in a reduced pressure state.

The built-in controller incorporated in the energizing circuit of the motor 6 sets the forward rotation drive of the gear pump 7 for a fixed time, and after the forward rotation drive is stopped, the rotation is instantaneously switched to reverse rotation. Reverse operation is performed within 1 second.

The intermittent greasing system used in the depressurizing method of the present invention has the above-mentioned structure. Next, the intermittent greasing and depressurizing method will be described.

As shown in FIG. 1, the push button spool 8 is in a state in which the pressure suppressing / depressurizing spool 9 of the switching valve 10 is in the original position.
1 from the outside to the left in FIG. 1, the taper cam portion 22
Pushes the limit switch 25 to turn on the contact, and the motor 6 starts forward rotation drive.

The gear pump 7 directly connected to the motor 6 rotates and the lubricating oil such as grease filled in the storage chamber 1 is stored in the chamber 1.
5 and the suction port 14 of the gear pump 7 to be guided to the discharge port 17 of the gear pump 7. The lubricating oil in the discharge port 17 gradually increases in pressure, and the pressure control / depressurization spool 9 is pushed and moved to the left side in FIG. Then, the passage 19 is closed by the proximal side head portion 28 of the spool 9.

At this time, as shown in FIG. 2A, the discharge port 17 of the gear pump 7 and the discharge passage 20 communicate with each other, and the lubricating oil is
After reaching the piston type distributor 4 through the passage 21, the discharge port joint 13 and the pipe 3, the piston type distributor 4 is discharged at a predetermined working pressure and then heads to the lubrication point.

After the piston type distributor 4 finishes discharging,
The pipeline becomes a closed circuit, and the pressure in the pipeline is further increased by driving the gear pump 7.

Along with this increase in pressure, the pressure control / depressurization spool 9 further moves by compressing the spring 27 to the left side in FIG. 1, and as shown in FIG. When balanced with, the passage 19 is opened and communicates with the discharge port 17 and the discharge passage 20, so that a part of the lubricating oil discharged from the gear pump 7 returns to the storage chamber 1a, and the inside of the pipe line has a predetermined pressure. It is kept under control.

When the pump operation time set by the controller incorporated in the electric circuit has elapsed, the motor 6 instantaneously switches from normal rotation to reverse rotation by internal control, and performs reverse operation within 1 second, for example.

By this reverse rotation operation, the functions of the suction port 14 and the discharge port 17 of the gear pump 7 are reversed, and the pressure suppressing and depressurizing spool 9 is moved by the restoring force of the spring 27 and the suction pressure of the gear pump 7 as shown in FIG. It is forcibly sucked to the right from the state.

Due to the above-mentioned suction action, the pressure suppressing / depressurizing spool 9 returns to the original position shown in FIG.
Since 0s communicate with each other, the depressurizing action in the pipe 3 becomes smooth, and therefore the reliable operation of the piston type distributor 4 in the intermittent lubrication system of lubricating oil can be guaranteed.

[0031]

As described above, according to the present invention, after the pump is stopped by the normal rotation of the motor, the motor is quickly rotated in the reverse direction. Therefore, the suction force by the reverse rotation of the pump is used to drive the switching valve. The return force of a certain spring can be supplemented, and the intermittent greasing system can be reliably depressurized.
The grease storage operation of the distributor becomes accurate, and quantitative distribution can be realized.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a depressurizing device of an intermittent greasing system.

FIG. 2 (A) is an enlarged vertical sectional view showing a pressurized state of the switching valve in the same as above, and FIG. 2 (B) is an enlarged vertical sectional view showing a suppressed state before starting depressurization.

FIG. 3A is an enlarged front view of a push button spool in a switching valve, and FIG. 3B is an enlarged front view of a pressure suppression and depressurization spool.

[Fig. 4] Circuit diagram of intermittent greasing system

[Explanation of symbols]

 1 Storage Container 2 Greasing / Depressurizing Mechanism 3 Piping 4 Distributor 5 Pump Body 6 Motor 7 Gear Pump 8 Push Button Spool 9 Suppressing / Depressurizing Spool 15 Chambers 16, 19, 21 Passage 20 Discharge Passage 25 Limit Switch

Claims (1)

[Claims] 1. A gear pump provided between a lubricating oil storage chamber and a discharge passage is driven by a motor to send out the lubricating oil in the storage chamber toward the discharge passage, and is located between the discharge port and the discharge passage of the gear pump. In the intermittent greasing system in which the switching valve for switching the spool movement due to the pressure fluctuation of the discharge lubricating oil switches the communication between the discharge port of the gear pump and the discharge passage and the storage chamber, the pump drive by the normal rotation of the motor A depressurizing method for an intermittent greasing system, characterized in that after the motor is stopped, the motor is immediately rotated in the reverse direction, and the depressurizing operation for communicating the discharge passage of the switching valve with the storage chamber is assisted by the suction force generated by the reverse rotation of the gear pump.