JP2001182659A - Liquid supply method, liquid supply pump suitable for being used in this method and liquid supply device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive liquid supply device capable of accurately supplying liquid of a prescribed supply quantity in a prescribed time and generating no bubble regardless of viscosity of the liquid. SOLUTION: In this liquid supply device 100 of one embodiment, the inside of a piston housing is divided into two parts by a single diaphragm 130; one is formed as a piston chamber 121; a piston 140 is made to internally exist; a cam 170 controlled by a servomotor 160 is brought near to this; the other chamber is formed as a liquid sub-tank chamber 122; a pressurized liquid L from a liquid pressurizing tank 210 is injected; and the piston 140 is pushed away rightward via the diaphragm 130. When rotating the cam 170 by half, the diaphragm 130 is pushed away by the piston 140, so that liquid L in the liquid sub-tank chamber 122 can be supplied outside from a discharge means such as a nozzle through a liquid discharge valve 330 from an entrance 125.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of accurately supplying a predetermined amount of a liquid such as an ink or a solvent within a predetermined time regardless of the viscosity of the liquid. The present invention relates to a liquid supply system, a liquid supply pump suitable for the system, and a liquid supply device.

[0002]

2. Description of the Related Art Conventionally, as a liquid supply system, there are various systems using a diaphragm type pump, a bellows type pump, a cylinder, etc., in which a liquid in a tank is pressurized and supplied by opening and closing a valve.

[0003]

The above-mentioned pressurizing and valve opening / closing system is a system in which the liquid pressurized in the tank is controlled only by opening / closing the valve. Inferior.

The diaphragm pump system is a system in which the diaphragm is driven by a combination of air and vacuum, or a piston shaft driven by a motor, so that it is inexpensive, but the control accuracy is poor and the air in the liquid is inferior. And cavitation easily occur.

[0005] The bellows pump system is inexpensive, but inferior in quantitative supply and is susceptible to the viscosity of the liquid.

Further, although the cylinder system is excellent in fixed-quantity supply, it is easily affected by the viscosity of the liquid.
In addition, since the liquid and the cylinder are in direct contact with each other, the sealing performance on the sealing surface is inferior, and liquid leakage easily occurs.

As described above, each system has advantages and disadvantages.

Accordingly, the present invention is intended to solve these problems, and irrespective of fluctuations in the viscosity of a liquid.
An inexpensive liquid supply method capable of accurately supplying a predetermined supply amount of liquid within a predetermined time and preventing the incorporation of bubbles, a liquid supply pump suitable for the method, and a liquid supply device therefor. With the goal.

[0009]

Therefore, according to the first aspect of the present invention, the liquid in the liquid pressurizing tank is continuously pressurized and maintained, and the liquid has an elastic surface on a part of the wall surface. The above object is attained by adopting a liquid supply method in which pressurization and depressurization operations are repeatedly repeated at a constant interval on the elastic wall surface when passing through the liquid sub-tank.

[0010] According to the second aspect of the present invention, the liquid supply pump is provided with one diaphragm incorporated in the piston housing, and the inside of the piston housing is divided into two chambers. The piston head of a piston comprising a piston head and a piston shaft connected to the piston head for moving the piston head is disposed so that the piston head can move. A pump provided with a liquid port in the other of the two chambers, and a piston drive device for moving the piston shaft of the pump. The problem has been solved.

According to a third aspect of the present invention, in the liquid supply pump according to the second aspect, the piston driving device includes: a servomotor; a gear unit connected to a rotation shaft of the servomotor; The problem is solved by comprising a cam connected to a gear unit and a controller / driver for controlling the rotation of the servomotor.

Further, in the invention according to claim 4,
In the liquid supply pump according to claim 2, the cam according to claim 3 is provided such that a peripheral surface of the cam is disposed close to an end of the piston shaft according to claim 2, wherein The above problem is solved by providing an adjusting device for adjusting a distance between an end portion and a peripheral surface of the cam.

Further, according to a fifth aspect of the present invention, in the liquid supply pump according to the second to fourth aspects, the cam according to the third and fourth aspects is configured such that the servomotor is driven by the servomotor.
By rotating the liquid supply, one cycle of liquid supply is completed to solve the above-mentioned problem.

Further, in the invention according to the sixth aspect, the liquid supply device is constructed such that a single diaphragm is incorporated in the interior of the piston housing and the interior of the piston housing is divided into two chambers, and one of the two chambers is provided. , A piston head connected to the piston head and configured to move the piston head by a piston is disposed so that the piston head of the piston can perform the piston movement, and the piston shaft is the piston on the one chamber side. A liquid supply pump disposed in a state of being led out of the housing and having a liquid inlet / outlet formed in the other of the two chambers; a piston drive device for causing the piston shaft of the pump to perform piston movement; and the pump A liquid pressurizing tank for pressurizing and supplying and injecting a predetermined amount of liquid from the liquid port to the other chamber side; A liquid supply source for supplying a predetermined amount of liquid before pressurization to the tank, and a pressurizing gas for supplying a pressurized gas for pressurizing the surface of the liquid injected into the liquid pressurized tank at a constant pressure. A pressurized gas supply source, a liquid supply valve led out from below the liquid pressurized tank and sequentially connected from the liquid pressurized tank side to a pipe arranged on the liquid inlet / outlet side of the other chamber of the pump. A liquid discharge valve, a discharge means connected to the liquid discharge valve, a supply / discharge pipe connecting an intermediate portion between the liquid supply valve and the liquid discharge valve, and the liquid inlet / outlet of the pump, and the liquid supply valve And a switching device for alternately switching between a liquid supply function and a liquid discharge function of the liquid discharge valve and the liquid discharge valve.

Further, in the invention according to claim 7, the liquid supply pump of the liquid supply device according to claim 6 is constituted by the liquid supply pump according to claims 3 to 5, and The problem has been solved. According to the eighth aspect of the present invention, in the liquid supply apparatus according to the sixth aspect, the liquid supply valve is closed, the liquid discharge valve is opened, and the cam is rotated by the servo motor. Pressing a shaft, discharging the liquid injected into the liquid sub-tank through the liquid inlet / outlet and the liquid discharge valve, after discharging the liquid, opening the liquid supply valve, closing the liquid discharge valve, and By rotating the cam a further half turn, the cam returns to the standby position, and control is performed so as to increase the interval between the outer peripheral portion of the cam and the piston shaft, thereby solving the problem.

Therefore, according to the liquid supply method of the present invention, a predetermined amount of liquid can be accurately supplied from the liquid pressurized tank to the liquid sub-tank regardless of the viscosity of the liquid, and the liquid can be supplied from the liquid sub-tank to the outside. A predetermined amount of liquid can be supplied accurately, and the supply rate of the liquid can be precisely controlled.

According to the liquid supply pump of the second aspect, there is no entrainment of air and no liquid leakage, and a predetermined amount of liquid can be supplied.

According to the liquid supply pump of the third aspect, in addition to the function and effect of the liquid supply pump of the second aspect, a predetermined amount of liquid can be supplied accurately.

According to the liquid supply pump of the fourth aspect, in addition to the operation and effect of the liquid supply pump of the second aspect, the amount of liquid to be supplied by adjusting the interval between the piston shaft and the cam. Can be easily adjusted, and by controlling the rotation of the cam, the liquid supply rate can be controlled.

Further, according to the liquid supply pump of the fifth aspect, in addition to the operation and effect of the liquid supply pump of the second to fourth aspects, a predetermined amount of liquid can be accurately supplied by a half rotation of the cam. In the other half rotation, a predetermined amount of liquid can be accurately injected into the liquid sub-tank.

Furthermore, according to the liquid supply apparatus of the sixth aspect, the liquid supply apparatus can be configured at a very low cost, regardless of the viscosity of the liquid, and without causing entrainment of air, generation of cavitation, and liquid leakage. A predetermined amount of liquid can be accurately supplied within a predetermined time.

Further, according to the liquid supply device of the present invention, in addition to the operation and effect of the liquid supply device of the sixth embodiment, a predetermined amount of liquid can be accurately supplied by an inexpensive pump. The feed rate can be precisely controlled.

According to the liquid supply apparatus of the eighth aspect, in addition to the function and effect of the liquid supply apparatus of the sixth aspect, a predetermined amount of liquid can be accurately supplied by half a rotation of the cam, and other liquid supply apparatuses can be provided. It is possible to perform a repetitive motion for accurately injecting a predetermined amount of liquid into the liquid sub-tank by half a rotation.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will now be described with reference to FIGS. 1 to 3. FIG.

FIG. 1 is a configuration diagram of a liquid supply device according to one embodiment of the present invention. FIG. 2 is a configuration diagram showing the liquid supply device shown in FIG. FIG. 3 is a block diagram of a control device suitable for controlling the liquid supply pump of the liquid supply device shown in FIG.
First, the configuration of a liquid supply device according to an embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, reference numeral 1 indicates a liquid supply device of the present invention. The liquid supply device 1 is roughly composed of a liquid supply pump section 100, a liquid pressurization section 200, and a liquid supply / discharge pipe 300 of the present invention.

The liquid supply pump section 100 also includes a liquid supply pump 110 and a piston driving device 150 for the liquid supply pump 110.

The liquid supply pump 110 includes a frame 111
A single diaphragm 130 forming an elastic wall is incorporated in an intermediate portion inside a piston housing 120 having a predetermined capacity and fixed inside, and the inside of the piston housing 120 is divided into two chambers. Is a piston chamber 121, and the other chamber is a liquid sub-tank chamber 122.
In the piston chamber 121, the piston head 1
41 and a piston shaft 142 connected to the piston head 141 for piston movement of the piston head 141 are arranged so that the piston head 141 of the piston 140 can perform piston movement. It is disposed in a state of being led out from the side wall 123 of the piston housing 120,
The liquid sub-tank chamber 122 facing the side wall 123
Liquid L on the side wall 124 of the piston housing 120 on the side
Is formed in a structure in which an entrance 125 is formed.

As shown in FIG. 3, the piston driving device 150 for moving the piston shaft 142 by a piston includes a servo motor 160 and the servo motor 16.
A gear unit 162 connected to the 0 rotation shaft 161;
The gear unit 162 includes, for example, an elliptical cam 170 connected to the gear unit 162, and a controller / driver 180 for controlling the rotation of the servo motor 160. The cam 170 has a camshaft 171 connected to a rotary shaft 161 of the servomotor 160 by a joint 172.

The cam 170 has a peripheral surface 170.
A is disposed close to the end of the piston shaft 142, and a micrometer 190 which is an adjusting device for adjusting a gap G between the end of the piston shaft 142 and the peripheral surface 170A of the cam 170. Are disposed close to the servomotor 160. In the illustrated example, the cam 170 is configured to complete one cycle of liquid supply by making one rotation with the servo motor 160.

The liquid pressurizing section 200 includes a liquid pressurizing tank 210 and a liquid replenishing pump 220 constituting a liquid replenishing source.
And a regulator 230 and an air gauge 240 that constitute a pressurized gas supply source.

The liquid pressurized tank 210 is a device for supplying and injecting a predetermined amount of liquid L from the inlet / outlet 125 to the liquid sub-tank chamber 122 via a liquid supply / discharge pipe 300 described later. The liquid L before pressurization is supplied to the liquid pressurized tank 210 from the liquid supply source by the liquid supply pump 220 in a fixed amount. The surface of the liquid contained in the liquid pressurized tank 210 is pressurized by a pressurized gas source of the pressurized gas supply source, in this case, pressurized air from a pressurized air source (not shown). The liquid is supplied from above the liquid pressurizing tank 210 via 230 and pressurized at a constant pressure. The pressure is constantly monitored by the air gauge 240.

The liquid supply / discharge pipe 300 is led out from below the liquid pressurized tank 210, and is sequentially connected to the pipe 310, which is connected to the entrance 125 of the liquid subtank chamber 122, from the liquid pressurized tank 210 side. Connected liquid supply valve 320 and liquid discharge valve 330
A discharge means 340 such as a nozzle connected to the liquid discharge valve 330;
0 and the liquid discharge valve 330, and the other end is connected to the entrance 125 of the liquid sub-tank chamber 122.
And a supply / discharge pipe 350 connected to the supply port.

The liquid supply device 1 of the present invention is configured as described above. Next, this operation will be described. First, as shown in FIG.
The piston head 141 is retracted so as to contact the side wall 123 of the piston housing 120, and the short-axis side of the cam 170 of the piston drive device 150 is slightly moved between the piston 170 and the end of the piston shaft 142 of the liquid supply pump 110. The interval G is set using the micrometer 190 so as to be widened. At the position (width of the gap G) of the cam 170 (cam shaft), the supply amount (or discharge amount) of the liquid L
The discharge speed is determined by the rotation speed of.

Next, the liquid L is supplied and supplied to the liquid pressurized tank 210 from the liquid supply source by the liquid supply pump 220, and the regulator 230 is supplied from the pressurized gas supply source.
, The surface of the liquid L contained in the liquid pressurizing tank 210 is continuously pressurized and maintained.

First, the liquid supply valve 320 is opened, the liquid discharge valve 330 is closed, and the pipe 31 is closed.
A predetermined amount of liquid L is supplied from the inlet / outlet 125 to the liquid sub-tank chamber 122 through the liquid supply valve 320 and the supply / discharge pipe 350. The supply amount of the pressurized liquid L is determined by the capacity of the liquid sub-tank chamber 122, and the capacity is determined by the capacity of the piston housing 120 and the diaphragm 1
It is determined by 30 partition positions.

The liquid L pressurized and supplied into the liquid sub-tank chamber 122 is applied to the diaphragm 13 forming an elastic wall surface.
When 0 is pressed, the piston head 141 of the piston chamber 121 is pressed against the side wall 123 by the pressure of the pressurized liquid L, and comes into contact with the side wall 123 and stops. With this operation, the predetermined amount of the liquid L is injected into the liquid sub-tank chamber 122 (the state of FIG. 1).

Next, a predetermined amount of liquid L injected into the liquid sub-tank chamber 122 from the liquid measuring state shown in FIG.
Will be described. The controller / driver 1
The servo motor 160 is operated under the control of 80,
As shown in FIG. 2, the cam 170 is driven to rotate,
70 is rotated half a turn so that the cam surface on the long axis side
Is pressed. At the same time, the liquid supply valve 32
0 is closed and the liquid discharge valve 330 is opened. As shown in FIG. 2, the piston 140 presses and moves to the left, pushes the diaphragm 130 having an elastic surface, and presses the predetermined amount of the liquid L injected into the liquid sub-tank chamber 122.
Extrude. The extruded liquid L is in the liquid sub-tank chamber 1
The liquid is discharged (supplied) from the discharge means 340 to the outside through the supply / discharge pipe 350 and the liquid discharge valve 330 from the entrance 125 of the nozzle 22.

When a predetermined amount of liquid L is discharged, the servo motor 1 is controlled under the control of the controller / driver 180.
Activate the cam 170 to rotate the cam 170 half a turn.
To the standby position as shown in FIG.
A gap G is provided between the end of the cam 42 and the end of the cam 170.

Next, the liquid discharge valve 330 is closed, the liquid supply valve 320 is opened, and the liquid L pressurized from the liquid pressurizing tank 210 is sucked (injected) into the liquid sub-tank chamber 122 in the same manner as described above. .

In the above-described embodiment, the liquid supply device has been described as having a one-cycle configuration in which the supply (discharge or discharge) of the liquid L and the preparation (injection) of the liquid L are completed by one rotation of the cam 170. One rotation of the cam may perform two or more cycles of liquid and suction operations.

The reason why the piston driving device 150 is composed of the servomotor 160 and the gear unit 162 is that the accurate supply amount (discharge amount, or discharge amount) of the liquid is controlled by the rotation control accuracy of the cam 170 and the position adjustment accuracy of the cam. Since the discharge amount) and the supply time (discharge time or discharge time) are determined, they are used to improve the rotational speed and position accuracy of the cam 170 in the cycle.

As described above, the liquid supply device 1 of the present invention continuously pressurizes and maintains the liquid L in the liquid pressurizing tank 210, and applies the liquid L to a part of the wall surface by the diaphragm 130. When the liquid L is passed through the liquid sub-tank chamber 122 formed on the elastic surface, the operation of pressurizing and depressurizing the diaphragm 130 (elastic wall surface) is continuously repeated at a constant interval, so that the liquid L can be accurately discharged. And the fixed amount of liquid can be supplied (discharged or discharged) to the outside.

[0044]

As described above, according to the liquid supply apparatus of the present invention, it is possible to: Regardless of the viscosity of the liquid, a predetermined amount of liquid
1. It can be supplied accurately within a predetermined time. The liquid supply amount can be easily controlled by changing the distance between the cam position and the end of the piston. There is no entrapped air or cavitation in the liquid to be supplied (discharged or discharged). 4. 4. Since the piston chamber and the liquid sub-tank chamber are separated by the diaphragm, no liquid leakage occurs when measuring the volume. A number of excellent effects can be obtained, such as a low-cost configuration without requiring a large investment.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a liquid supply device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating the liquid supply device in a state of liquid measurement illustrated in FIG. 1 in a state of liquid supply.

FIG. 3 is a configuration diagram of a control device suitable for controlling a liquid supply pump of the liquid supply device shown in FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Liquid supply apparatus of one Embodiment of this invention, 100 ... Liquid supply pump part of this invention, 110 ... Liquid supply pump, 12
0: piston housing, 121: piston chamber, 122
... liquid sub-tank chamber, 125 ... liquid sub-tank chamber 122
Liquid inlet / outlet, 150 ... piston drive, 160 ...
Servo motor, 170: cam, 180: controller /
Driver, 190: Micrometer, 200: Liquid pressurizing unit, 210: Liquid pressurizing tank, 220: Liquid replenishing pump, 230: Regulator, 240: Air gauge, 3
00: liquid supply / discharge piping, 310: pipe, 320 ...
Liquid supply valve, 330: liquid discharge valve, 340: discharge means such as nozzle, 350: supply / discharge pipe

Claims (8)

[Claims] 1. A liquid in a liquid pressurizing tank is continuously pressurized and maintained, and when the liquid passes through a liquid sub-tank having an elastic surface on a part of the wall, the liquid continuously contacts the elastic wall. Wherein the pressurizing and depressurizing operations are repeated at regular intervals. 2. A single diaphragm is incorporated in a piston housing, and the inside of the piston housing is divided into two chambers. A piston head and a piston head are connected to one of the two chambers, and the piston head is caused to perform a piston movement. The piston head of a piston constituted by a piston shaft is disposed so as to be able to perform a piston movement, and the piston shaft is disposed in a state where the piston shaft is led out of the piston housing on the one chamber side. A liquid supply pump, comprising: a pump having a liquid inlet / outlet formed in the other chamber of the chamber; and a piston drive device for moving the piston shaft of the pump. 3. A servo motor, a gear unit connected to a rotating shaft of the servo motor, a cam connected to the gear unit, and a controller / driver for controlling rotation of the servo motor. The liquid supply pump according to claim 2, comprising: 4. A cam according to claim 3, wherein a peripheral surface of the cam is disposed close to an end of the piston shaft according to claim 2, and the end of the piston shaft and the end of the cam are arranged. The liquid supply pump according to claim 2, further comprising an adjusting device that adjusts a distance from the peripheral surface. 5. The liquid supply apparatus according to claim 2, wherein one cycle of the liquid supply is completed by rotating the cam according to claim 3 by one turn by the servo motor. The liquid supply pump according to claim 4. 6. A piston housing having a single diaphragm incorporated therein, the interior of the piston housing is divided into two chambers, and one of the two chambers is connected to a piston head and the piston head to move the piston head. The piston head of a piston constituted by a piston shaft is disposed so as to be able to perform a piston movement, and the piston shaft is disposed in a state where the piston shaft is led out of the piston housing on the one chamber side. A liquid supply pump in which a liquid port is formed in the other chamber of the chamber; a piston drive device for causing the piston shaft of the pump to make a piston movement; and a fixed amount of liquid from the liquid port of the pump to the other chamber. A liquid pressurizing tank for supplying and injecting under pressure, and a liquid supplementing tank for replenishing the liquid pressurizing tank with liquid before pressurization in a fixed amount. A supply source, a pressurized gas supply source for supplying a pressurized gas for pressurizing the surface of the liquid injected into the liquid pressurized tank with a constant pressure, A liquid supply valve and a liquid discharge valve sequentially connected from the liquid pressurized tank side to a pipe provided on the liquid inlet / outlet side of the other chamber of the pump, and discharge means connected to the liquid discharge valve; A supply / discharge pipe connecting an intermediate portion between the liquid supply valve and the liquid discharge valve and the liquid inlet / outlet of the pump; and alternately providing a liquid supply function and a liquid discharge function of the liquid supply valve and the liquid discharge valve. And a switching device for switching to the liquid supply device. 7. The liquid supply apparatus according to claim 6, wherein the liquid supply pump is the liquid supply pump according to any one of claims 3 to 5. 8. The liquid supply valve is closed, the liquid discharge valve is opened, the cam is rotated by the servomotor to press the piston shaft, and the liquid injected into the liquid sub-tank is removed by the liquid. The liquid is discharged through an inlet / outlet and the liquid discharge valve, and after discharging the liquid, the liquid supply valve is opened, the liquid discharge valve is closed, and the cam is further rotated half a turn so that the cam returns to the standby position. 7. The apparatus according to claim 6, wherein a control is performed so that a gap is provided between an outer peripheral portion of the piston and the piston shaft.
The liquid supply device according to item 1.