JPS585218Y2 - Liquid quantitative supply device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid quantitative supply device that can stably supply a fixed amount of liquid from a liquid storage tank to a liquid receiver.

Generally, when a liquid is supplied to a liquid receiver, it is often required that the amount of liquid supplied be constant, that is, neither too much nor too little of an appropriate level.

For example, a unitized differential (a type of differential device).

In a break-in machine (hereinafter simply referred to as a differential), if the amount of lubricant supplied is larger than a predetermined amount, the lubricant overflows from around the load shaft, and the excess lubricant is forced out. If the lubricating oil is supplied too much, failures such as damage to the oil seal that seals the lubricating oil will occur.On the other hand, if the lubricating oil is supplied in a small amount, the cleaning effect will decrease, and if the lubricating oil becomes even less, the cleaning effect will decrease. This causes problems such as seizure on the tooth surface of the gear.

Therefore, several types of lubricating oil quantitative supply devices have been used in the past, one of which is to connect an oil feed pump to the oil flow path that connects the oil reservoir and the differential, and to connect the pump to the differential. A solenoid valve and a variable throttle valve are connected to the valve, and the throttle valve adjusts the amount of lubricating oil flowing through the oil flow path.A timer is connected to the solenoid valve or the pump, and the timer controls the operation of the pump. There was a type that supplied a fixed amount of lubricating oil to the differential by controlling the time or the excitation time of the solenoid of a solenoid valve.

However, such a supply device has the drawback that the viscosity of the lubricating oil changes due to changes in ambient temperature, changing its flow resistance, and as a result, the amount of lubricating oil supplied to the differential is not constant.

In addition to this, clogging of the filter installed on the pump suction side to prevent foreign matter from being inhaled, clogging in the middle of the piping, and errors in the timer can also make it difficult to supply lubricating oil at a constant rate. Ta.

In addition, as another lubricating oil fixed quantity supply device, a flow path communicating with the oil storage tank and a flow path communicating with the shaft are each connected to the measuring chamber of the measuring cylinder, and a check valve is installed in each of these two flow paths. The metering piston of the metering cylinder is reciprocated by another driving cylinder, and after a certain amount of lubricating oil is stored in the metering chamber from the oil storage tank by the backward stroke of the metering piston, the same amount is stored by the forward stroke of the metering piston. Devices for supplying a quantity of lubricating oil to a differential were also known.

However, although this device avoids the problem of oversupply of lubricating oil, it can continue to operate even if the liquid level in the oil reservoir drops and air is sucked into the metering cylinder. The amount of lubricant supplied to the differential is insufficient or not supplied at all, but it is overlooked.
The risk of insufficient cleaning effect or seizure of tooth surfaces still cannot be avoided.

Of course, this problem also exists in the above-described apparatus in which the amount of lubricant supplied is determined by regulating the supply time.

□The present invention has been made with the aim of eliminating the drawbacks of the above-mentioned prior art, and its gist is to provide a measuring cylinder that selectively communicates with a liquid supply passage and a liquid discharge passage through a valve. , wherein a backward stroke of the metering piston in the metering cylinder causes an amount of liquid corresponding to the backward stroke to be accommodated in the metering cylinder from the liquid storage tank through the liquid supply passage, and whose magnitude is equal to the backward stroke of the metering piston. A pipe connecting a liquid storage tank and a measuring cylinder in a liquid metering supply device that supplies a fixed amount of stored liquid to a target liquid receiver through the liquid discharge passage by a forward stroke of the cylinder. A liquid feeding pump that can pump liquid but not gas is connected in the middle of the passage, and allows the metering piston to move backward due to the pressure of the liquid sent from the liquid pump to the metering cylinder, while moving forward in the forward direction. The system is equipped with a metering piston drive device that forcibly moves the metering piston, and the metering piston inevitably stops moving back when the liquid pump sucks in gas and becomes unable to send liquid.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to drawings showing an embodiment of the present invention applied to a device for supplying a predetermined amount of lubricating oil to a differential.

In FIG. 1, 1a is an oil storage tank containing lubricating oil 1b.

A pipe line 2a as a lubricating oil supply passage is inserted into this oil storage tank 1a, and a filter 2C is attached to the tip of the pipe line 2a, and the other end of this pipe line 2a is connected to a measuring chamber 7C of a measuring cylinder 7a. ing.

In the middle of this pipe 2a, there is a pump 4, such as a gear pump or a centrifugal pump, which can pump liquid but cannot pump gas.
is connected to the pump 4 so that the lubricating oil 1b in the oil storage layer 1a can be sucked up and pumped to the metering cylinder 7a.

An electromagnetic on-off valve 5 is inserted between the pump 4 and the metering cylinder 7a in this conduit 2a, and a solenoid 5a is inserted between the pump 4 and the metering cylinder 7a.
The pump 4 is activated based on an electrical signal sent to the
The lubricating oil 1b fed under pressure from the lubricating oil 1b can be circulated or blocked.

Further, 12 is a relief valve.

On the other hand, a conduit 2b is connected to the differential 3, and the other end of this conduit 2b is connected to a measuring chamber 7C of a measuring cylinder and cylinder 7a, and the lubricating oil 1b measured by the measuring cylinder 7a is transferred to the differential.
It forms a discharge passage that leads to.

In the middle of this conduit 2b, an electromagnetic on-off valve 6 is inserted which operates based on an electric signal sent to a solenoid 6a.

・ . A metering piston 7b built into the metering cylinder 7a is connected by a connecting rod 11 to a piston 9b of an air cylinder 9a serving as a metering piston driving device.

This air cylinder 9a is a single-acting cylinder that is supplied with pressurized air only to the piston side chamber 9C from an air supply source 13 via an electromagnetic switching valve 14.

Dogs 8b and 8b are attached to the connecting rod 11 so that their positions can be adjusted, and limit switches 8C and 3d, which are activated by contact between the dogs 8a and 8b, are arranged at appropriate intervals along the connecting rod 11. Based on the signals from the limit switches 8C and 8d, the electromagnetic on-off valves 5 and 6 and the electromagnetic switching valve 14 are operated as described in detail below.

When the electromagnetic on-off valve 5 is opened, the lubricating oil 1b sucked up from the oil storage tank 1b by the pump 4 is pumped through the electromagnetic on-off valve 5 to the metering cylinder 7a.

At this time, the metering piston 7b is moved back by the pressure of the fed lubricating oil, and the lubricating oil is accommodated in the metering chamber 7C.

When the required amount of lubricating oil is contained in the metering chamber 7C, the dog 8b attached to the connecting rod 11, which retreats together with the metering piston 7b, comes into contact with the limit switch 8d.

As a result, the solenoid 5a is demagnetized, the pipe line 2a is cut off, the supply of lubricating oil to the metering cylinder 7a by the pump 4 is cut off, and the quantitative supply device waits in this state.

The differential 3 is connected to the conduit 2b, and based on the connection completion signal, the solenoid 6a is energized to open the conduit 2b, and the electromagnetic switching valve 14 is switched to the state on the left side in FIG. 1 to open the air cylinder 9a. starts operating.

Due to the operation of this air cylinder 9a, the metering piston 7b
is moved forward, and a certain amount of lubricating oil 1b stored in the metering chamber 7C is supplied to the differential 3 via the conduit 2b.

Then, at the same time when the metering piston 7b reaches the forward end and stops, the dog 8a contacts the limit switch 8C, and as a result, the electromagnetic switching valve 6 is closed, and the electromagnetic switching valve 14
is returned to the state on the right side in FIG. 1, and the operation of the -cycle is completed.

Lubricating oil 1 is supplied to differential 3 using such a lubricating oil quantitative supply device.
When supplying lubricating oil b, the lubricating oil sucked up by the pump 4 from the oil storage tank 1a is once introduced into the measuring cylinder 7a and a predetermined amount of lubricating oil is accumulated in the measuring chamber 7C, and then is supplied to the differential 3 for the first time. Therefore, in addition to adjusting the flow rate with a throttle valve, the operating time of the pump for pressure-feeding lubricating oil or the temperature can be controlled using a timer to control the solenoid valve installed in the flow path. This prevents changes in the amount of lubricating oil supplied due to changes in the viscosity of the liquid that occur as a result of changes in the viscosity of the liquid.

Also, the lubricating oil 1b sent to the measuring cylinder 7a is supplied to the pump 4.
Since the lubricating oil 1b in the oil storage tank 1a decreases and the oil level drops, and air is sucked in from the filter 2C attached to the tip of the pipe line 2, the pump 4 does not force the gas to the metering cylinder 7a, so the metering piston 7b does not move back, and the operation of the device stops, indicating that the supply of lubricating oil has been stopped, so sufficient lubricating oil is not supplied to the differential 3. It is possible to reliably avoid problems such as insufficient cleaning effect and seizure of the tooth surfaces due to the break-in operation of the differential 3 starting immediately.

Since the air cylinder 9a used in the embodiment described above is not required to move the metering piston 7b backward, the air supply source is connected to the rod side chamber 7d of the metering cylinder 7a via the electromagnetic switching valve 14, as shown in FIG. By connecting 13, it is possible to omit the air cylinder 9a, which has the advantage of simplifying the device.

Further, the pump 4 does not necessarily have to be provided in each quantitative supply device, and can be shared and used by a plurality of quantitative supply devices.

Furthermore, it is of course possible to use the embodiment apparatus described in detail above to supply a fixed amount of liquid other than lubricating oil, and the present invention does not exclude such a case.

As described in detail above, in the present invention, when the liquid pumped to the measuring cylinder by the liquid pump reaches a certain amount, the measuring piston is moved forward by a driving device such as an air cylinder.
By providing a liquid constant supply device that supplies liquid in a measuring cylinder to a liquid receiver, it is possible to stably supply a fixed amount of liquid to the liquid receiver, thereby eliminating various problems caused by excessive or insufficient supply of liquid. This has the effect of preventing harmful effects before they occur.

Furthermore, in the liquid quantitative supply device according to the present invention, the metering piston is forcibly moved in the forward direction by the drive device, but is moved in the backward direction by the pressure of the liquid pumped by the liquid pump. Since it is said that the liquid pump is unable to pump gas under pressure, if the liquid level in the liquid storage tank drops and the liquid pump sucks in air, the metering piston will retreat. No directional pressure acts, and the retraction of the metering piston is necessarily stopped.

Therefore, the operation of the liquid dispensing device itself stops there, and air is actually sucked into the metering cylinder, as when the metering piston is moved by a drive device both in the forward and backward directions. Even though a predetermined amount of liquid cannot be supplied, the operation of the liquid metering supply device continues as it is, and it is possible to reliably prevent various problems from occurring.

In addition, in a liquid metering supply device in which the metering piston is forcibly moved in both forward and backward directions, there is an attempt to prevent the above-mentioned malfunction from occurring due to detection of gas being sucked into the metering cylinder. For example, a special device is required to detect the suction of gas, which inevitably increases the cost of the device, but the liquid quantitative supply device according to the present invention does not require such a detection device. It is completely unnecessary and an increase in device cost can be avoided.

Furthermore, since the metering piston driving device only needs to be capable of driving the metering piston in one direction, the structure is simple and the cost of the device can be reduced.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams showing different embodiments of the present invention. 1a: oil storage tank, 11b: lubricating oil, 2a, 2b: pipe line, 3
: Differential, 4: Pump, 5, 6: Solenoid on/off valve, 5a, 6a
: Solenoid, 7a: Measuring cylinder, 7b: Measuring piston, 7C: Measuring chamber, 7d: 0'/de side chamber, 8a, 8b:
Dog, 8C, 8d: Limit switch, 9a: Air cylinder, 12: Relief valve, 13: Air supply source, 14
: Solenoid switching valve.

Claims (1)

[Scope of utility model registration request] A metering cylinder is provided that is selectively communicated with a liquid supply passage and a liquid discharge passage by a valve, and when a backward stroke of a metering piston in the metering cylinder causes a liquid to flow from the liquid storage tank through the liquid supply passage in an amount corresponding to the backward stroke. of liquid is contained in the metering cylinder, and by a forward stroke of the metering piston equal to the backward stroke, a certain amount of the contained liquid is transferred to the intended liquid receiver through the liquid discharge passage. In the liquid metering supply device of the supply type, a liquid pump capable of pumping liquid but not gas is connected to a pipe line connecting the liquid storage tank and the measuring cylinder, and A metering piston driving device is provided that allows the metering piston to move backward due to the pressure of the liquid sent from the pump to the metering cylinder, while forcibly moving the metering piston in the forward direction. 1. A liquid metering supply device, characterized in that, when liquid delivery becomes impossible due to suction, the metering piston inevitably stops retracting.