JP2003093942A - Device for ejecting fixed quantity of liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eject a liquid with high speed and high precision. SOLUTION: A device for ejecting fixed quantity of the liquid is constituted of a pump section which is composed of a plunger chamber bored in a cylinder block and of a plunger reciprocating in the plunger chamber and which measures an ejecting liquid by a desired quantity, a valve section for changing over a sucking liquid flow passage and a discharging liquid flow passage, a storing section for storing the liquid which can be communicated with the pump section according to a position of the valve section and an ejecting section provided with an ejecting port for ejecting the liquid. Further the device is characterized by that the pump section and the valve section are successively disposed and a most advanced position of the plunger is made to be a surface where a front end face of the plunger is joined to the valve section and the pump section. The valve section is disposed attachably and detachably to the pump section. The plunger chamber is constituted of a cylindrical member fitted into a hole bored in the cylinder block. The valve section is constituted of a changeover valve provided with a valve block having a first flow passage communicated with a storage vessel and a second flow passage communicated with the ejecting section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to liquids of all viscosities, for example, low-viscosity substances such as water and alcohol, to high-viscosity fluids such as adhesives and pasty or cream-like industrial materials. The present invention relates to a method and a device for discharging ink at high speed and with high accuracy.

[0002]

2. Description of the Related Art Conventionally, in a device for quantitatively discharging a liquid, (1) the compressed air whose pressure has been adjusted is applied to the liquid in a storage container for a desired time, and a desired amount of the liquid is discharged from the discharge port at the tip of the nozzle. (2) A plunger that discharges a desired amount of liquid from the discharge port at the tip of the nozzle by moving a plunger that is liquid-tightly arranged in the liquid in the storage container (3) A cylinder is provided between the storage container and the nozzle, and a plurality of through holes provided in the cylinder are provided such that one plunger moves forward and backward in one through hole. In the mechanism in which the liquid is sucked from the storage container into the cylinder by the backward movement, and the liquid is discharged from the cylinder to the nozzle by the forward movement of the plunger, the plurality of plungers sequentially act on the liquid to pressurize the liquid. It allows to discharge the desired amount of liquid from the discharge port of the nozzle tip, multiple-plunger pump discharge device, various ones such as have been developed.

[0003]

However, with these techniques, it has been impossible to discharge with a high takt time as required at present, with high accuracy and maintaining quantitativeness. For example, in the die bonding process and the like in semiconductor manufacturing, it is required to discharge a large amount in a short time due to the advent of large-sized devices having high performance and the demand for higher tact to improve productivity. On the other hand, since high quality products are required, high precision discharge and fine coating are required. In order to meet such a demand, the above-mentioned conventional techniques have problems.

For example, (1) the air-type discharge device uses air pressure as a pressure source for discharging liquid, but since the air pressure is rich in compressibility, it is very difficult to greatly change the pressure in a short time. Therefore, it is not suitable to discharge with a high-speed tact. In addition, even when it is necessary to apply a high pressure to the liquid, such as when a large amount of liquid is discharged in a short time and especially when the liquid to be discharged is a high-viscosity liquid, a sudden pressure change in the storage container Therefore, there is a limit in shortening the ejection time, and there is a problem that ejection cannot be performed with high-speed tact.

In the plunger type discharge device of (2), the plunger disposed liquid-tightly in the vicinity of the liquid head in the storage container is
This is a method of pressurizing and discharging all of the stored liquid. Here, since the amount of liquid to be pressurized depends on the residual liquid amount in the storage container, the desired pressure reaching time when the liquid agent is pressurized to the desired pressure is fast when the residual liquid amount is small, If the amount of residual liquid is large, it will be delayed. In this way, since the pressure change at the time of discharge differs depending on the residual liquid amount in the storage container,
Due to this, there is a problem that the ejection amount varies.
If the amount of liquid to be stored in advance is small, it is necessary to replace the storage container in a short cycle, which causes a problem that work efficiency deteriorates.

(3) In the multiple plunger pump type discharge device, since a plurality of plungers successively pressurize the liquid in sequence, when control is transferred from one plunger to another plunger Since the liquid is pressurized by the two plungers at the same time, the applied force is not uniform, so that there is a problem that pulsation occurs in the discharged liquid and the flow velocity is not uniform. Therefore, when liquid is applied and drawn on the work with this device in a line shape, unevenness and distortion occur in the line width and line height, making it impossible to form a uniform applied shape. In that case, it is practically impossible to form by coating.

An object of the present invention is to provide a discharging method and apparatus for discharging these liquids at high speed and with high precision by solving these problems associated with high-speed and highly-accurate quantitative discharge of liquids.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a plunger chamber bored in a cylinder block and a plunger reciprocating in the plunger chamber, a pump unit for measuring a desired amount of liquid to be discharged, and a suction and discharge unit. In the configuration of the valve unit that switches the liquid flow path, the storage unit that stores the liquid that can communicate with the pump unit depending on the position of the valve unit, and the discharge unit that has the discharge port that discharges the liquid, the pump unit and the valve unit. SUMMARY OF THE INVENTION A gist of a liquid constant-quantity discharge device is characterized in that the plungers are arranged in a continuous manner, and the most advanced position of the plunger is a surface where the front end surface of the plunger is joined to the valve portion and the pump portion.

The above-mentioned valve section is a switching valve having a valve block having a first flow path communicating with the storage container and a second flow path communicating with the discharge section. To a desired amount, a valve unit that switches between suction and discharge liquid flow paths, a storage unit that stores the liquid that can communicate with the pump unit depending on the position of the valve unit, and a discharge port that discharges the liquid. In the configuration including the discharge section, the pump section is composed of a cylinder block to which a cylinder provided with a plunger is mounted, and the valve section is connected to the first flow path and the discharge section communicating with the storage container. What is needed is a liquid constant-quantity discharge device characterized in that it is a switching valve having a valve block having a second flow path, and that the pump section and the valve section are arranged in series. It is set to.

The above-mentioned switching valve is a slide type switching valve, and in this case, the present invention comprises a pump section for metering the liquid to be discharged to a desired amount, and a valve section for switching the liquid channels for suction and discharge. In a cylinder block in which a cylinder equipped with a plunger is mounted, in a configuration including a storage portion that stores liquid and a discharge portion that discharges liquid, which is capable of communicating with the pump portion depending on the position of the valve portion. A pump part is configured, the valve part is a slide-type switching valve including a valve block having a first flow path communicating with the storage container and a second flow path communicating with the discharge part, and A gist of a liquid quantitative discharge device is characterized in that a pump portion and a valve portion are connected to each other.

By disposing the cylinder block and the valve block so as to be in intimate contact with and in sliding contact with each other, the pump section and the valve section are connected to each other. In that case, the present invention is
A pump unit that measures the amount of liquid to be discharged to a desired amount, a valve unit that switches the liquid flow paths for suction and discharge, a storage unit that stores the liquid that can communicate with the pump unit depending on the position of the valve unit, and discharges the liquid And a discharge section having a discharge port, wherein the pump section is composed of a cylinder block to which a cylinder equipped with a plunger is mounted, and the first flow path communicating the valve section with a storage container and the discharge section. A slide type valve valve having a second flow path communicating with the one side, a one-way rotation type, or a rotary type switching valve having a reciprocating smooth sliding surface, and
A gist of a liquid quantitative discharge device is characterized in that a pump part and a valve part are connected to each other by arranging a cylinder block and a valve block so as to be in intimate contact with each other and to slide together.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In a constant amount discharge method of a liquid, a liquid is sucked from a storage container into a plunger chamber by a retreating operation of a plunger, and the liquid is discharged from a plunger chamber to a nozzle by an advancing operation of the plunger. Is performed by one inhalation operation and one ejection operation of the plunger. Since the liquid is not pressurized by the plurality of plungers at the same time, the pressure applied to the liquid is constant, so that the discharged liquid does not pulsate and the flow velocity becomes uniform. Therefore, even if the liquid is applied and drawn in a linear shape on the work, unevenness and distortion do not occur in the width and height of the line, and a uniform applied shape can be formed.
A high-definition pattern shape can be formed by coating.
Furthermore, since the ejection is performed once by moving the plunger once, the ejected liquid has no pulsation and can be ejected at a constant flow rate, so that the desired drawing shape can be made uniform and high. It can be finely applied and formed.

Further, the discharge means that the liquid flows out from the nozzle due to the pressure difference between the liquid and the atmospheric pressure induced by pressurizing the liquid. The smaller the volume of the liquid to be pressed is, the more rapidly the liquid pressure can be raised, which is effective when a large amount of liquid is discharged in a short time, and especially when the discharged liquid is a high-viscosity liquid agent. Is. Therefore,
It is preferable to suck and pressurize the liquid into the plunger chamber with a single discharge amount, rather than pressurize the liquid amount corresponding to a plurality of discharge amounts. More preferably, there is no liquid remaining in the plunger chamber after the liquid has been discharged from the plunger. Since the amount of liquid to be discharged at one time is sucked into the plunger chamber and the liquid in the plunger chamber is discharged by applying pressure by moving the plunger, it is possible to minimize the amount of liquid to be pressurized, Therefore, it is possible to effectively eliminate the influence caused by the liquid, and it is possible to significantly shorten the time from the pressurization of the liquid until the liquid is ejected from the nozzle, which enables high-speed ejection. .

Here, it is preferable that the liquid suction start position and the liquid discharge end position of the plunger be the same for each discharge. To make the amount of liquid to be pressurized constant for each discharge always means that the amount of liquid to be pressurized does not depend on the amount of remaining liquid in the storage container, and the liquid pressure when the plunger pressurizes the liquid at the time of discharge Since the process of increasing the discharge amount can be equalized for each discharge, there is no variation in the discharge amount depending on the residual liquid amount in the storage container. More preferably, the liquid discharge start position of the plunger for each discharge is set to the same position, and the liquid discharge end position of the plunger for each discharge is set to the same position. Since the position of the plunger at the start and end of each discharge is always constant, the liquid compression amount is always constant regardless of the amount of liquid stored in the container, and stable and highly accurate discharge can be performed. . More preferably, the liquid suction start position of the plunger for each discharge is set to the same position, and the liquid suction end position of the plunger for each discharge is set to the same position.

A specific device configuration is such that a nozzle for discharging a liquid, a storage container for storing the liquid, a cylinder block having a plunger chamber inside, a plunger for moving forward and backward in contact with the plunger chamber, and driving the plunger. And a switching valve that connects the plunger chamber and the storage container or nozzle to each other. In this device, the plunger connected to the drive means moves back and forth in contact with the inner wall, the plunger retreats by an amount equal to the discharge amount, sucks the liquid from the storage container into the plunger chamber, and the plunger equals the discharge amount. Then, the liquid is discharged by moving from the plunger chamber to the nozzle. At this time, the switching valve connects the plunger chamber and the storage container when the plunger moves backward and sucks the liquid into the plunger chamber, and when the plunger moves forward and discharges the liquid from the plunger chamber, the switching valve connects the plunger chamber and the nozzle. Operates to communicate.

By connecting the storage container and the switching valve through the liquid feed pipe, the liquid agent storage portion and the discharge mechanism portion can be separated from each other, and therefore the storage container can be arranged in a place that is easy to handle. Yes, for example, when the remaining amount of liquid in the storage container is low, it is possible to easily perform the operation of replenishing the liquid storage container with liquid or replacing the entire storage container filled with liquid in advance. Become. Furthermore, considering the amount of liquid stored in the container from the pot life of the liquid to be used and the amount of work per day, it is possible to store an appropriate amount in a planned manner. It is also possible to eliminate the replenishment work of No. 1 or to replenish appropriately.

Further, since the discharge mechanism and the discharge port can be separated by connecting the nozzle and the switching valve through the liquid feed pipe, the discharge mechanism can be installed in the fixed portion and the nozzle can be moved. For example, since it becomes possible to mount the robot on a robot for working, the movable part can be made extremely lightweight. As a result, it becomes possible to perform the coating work, for example, the drawing work for coating the surface of the work in a desired pattern shape at an extremely high speed.

When the liquid in the storage container is a highly viscous fluid, or when the liquid is quickly sucked into the plunger chamber, suction by the backward movement of the plunger in order to transfer the liquid in the storage container to the plunger chamber. It is preferable to provide a pressurizing device for pressurizing the liquid in the storage container to assist the force.

The switching valve may be a slide type switching valve. Preferably, the switching valve is a slide valve including a valve block that has a first flow passage communicating with the storage container and a second flow passage communicating with the nozzle and that slides to switch the communicating portion. The closer the first flow path and the second flow path are to each other, the more the loss time at the time of switching can be shortened and the discharge can be performed at a high takt time.

The drive means and / or the switching valve can operate based on the signal of the control section. Preferably,
During discharge, the switching valve is controlled so that the plunger communicates with the nozzle, and the drive means is further controlled to pressurize the liquid, and during suction, the switching valve is controlled so that the plunger communicates with the storage container, and is further driven. Control means to aspirate liquid.

The number of plungers can be plural. At this time, since multiple different ejections can be performed with different plungers each time, when any one ejection operation of the plungers causes the other plunger to suck or stop, the liquid is ejected during the next ejection. Since the sucked plunger can quickly discharge the liquid, the time required for sucking the liquid can be effectively eliminated and a faster takt time can be achieved.

Furthermore, it is possible to make the driving means equal to the number of plungers. In addition, the plunger can be independently controlled. At this time, the discharge operation speed of the plunger when one plunger discharges the liquid and the suction operation speed when the other plunger sucks the liquid into the plunger chamber can be easily adjusted to different speeds. It is possible and preferable that one of the plurality of plungers has a speed suitable for discharging when engaged in discharging and a speed suitable for sucking when involved in sucking.

Further, the liquid ejection device of the present invention comprises a nozzle for ejecting a liquid, a storage container for storing the liquid, a plunger pump, a driving means for driving the plunger pump, a plunger chamber and a storage container or nozzle. And a cylinder block constituting the plunger pump and a valve block constituting the selector valve are arranged so as to be in intimate contact with and in sliding contact with each other. When the pump part and valve part are connected to each other and the tip of the plunger is on the surface where the valve block and cylinder block are joined, the suction operation is started and the discharge operation is completed. It is possible to pressurize the minimum necessary amount of liquid without compressing a certain amount of liquid, and it is possible to control the liquid with high responsiveness, so that it is possible to discharge with high-speed tact, and the plunger tip. Since the position is always constant for each ejection, it is possible to eject with high accuracy.

Therefore, liquid discharge and suction are switched by the forward / backward movement of the plunger, which is a component of the pump unit, and the movement of the valve block, which is a component of the valve unit, associated therewith. More specifically, the valve that is a component of the valve unit. When the position of the block is in a position where the pump section and the liquid storage section communicate with each other, the plunger moves backward to a position corresponding to the discharge amount, moves the liquid from the storage container into the plunger chamber, and starts the backward movement of the plunger. It is configured so that the liquid is discharged from the tip of the nozzle by retreating to the above position, and at this time, the tip position of the plunger at the start of retraction and at the time of completion of discharge is the surface where the valve block and the cylinder block are joined.

Here, the liquid is slightly compressible, and when pressurized, its volume is reduced. That is, in order to pressurize the liquid, it is necessary to compress the liquid, and it becomes more difficult to cause a steep pressure increase as the amount of liquid to be pressurized increases. For example, in this device, the higher the amount of liquid to be pressurized, the higher the moving speed of the plunger, and the pressure increasing process becomes unequal. That is, if the amount of liquid to be compressed is small, it is possible to increase the pressure with a small amount of movement of the plunger. Therefore, by setting the tip position of the plunger at the time of starting the retreat and at the time of completion of discharge to the surface where the valve block and the cylinder block are joined, the minimum amount of liquid required can be stored without storing excess liquid in the plunger chamber. It becomes possible to pressurize.

Further, since the pressure is applied to the required minimum amount of liquid, the liquid is ejected from the nozzle tip according to the operation of the plunger, and for example, from the nozzle ejection port although the plunger is stopped after the completion of ejection. The liquid does not continue to be discharged slowly, the delay of the discharge completion due to the expansion of the compressed liquid and the liquid sag can be eliminated, and the liquid can be controlled with high responsiveness. Further, by keeping the liquid suction start position and the liquid discharge completion position at the tip of the plunger at a constant position in this way, the amount of liquid to be pressurized is constant from the plunger tip to the nozzle tip. Therefore, the compression amount of the pressure buffer is always a constant amount, and therefore, the liquid amount for each ejection is stable and accurate ejection is possible.

Further, since one discharge is performed by one advance movement of one plunger, the liquid discharged from the nozzle tip has no pulsation. Further, since all the liquid sucked into the plunger chamber is discharged from the plunger chamber, there is no liquid staying in the vicinity of the plunger, and the liquid staying for a long time is not denatured in the plunger chamber. For example, the adhesive will not solidify and the plunger will not be fixed.

[0028]

The liquid discharge and suction are switched by the forward / backward movement of the plunger, which is a component of the pump section, and the movement of the valve block, which is the component of the valve section, which is accompanied by the movement of the plunger. When the parts are in communication with each other, the plunger retracts to a position corresponding to the discharge amount and sucks the liquid from the storage container by the amount to be discharged into the plunger chamber, and then the valve block communicates with the pump part and the nozzle part. To the position where the retreat movement has started, and the liquid is ejected from the nozzle tip. At this time, the tip end position of the plunger at the time of starting the retreat and at the time of completing the discharge is the surface where the valve block and the cylinder block are joined. Therefore, by setting the tip position of the plunger at the time of starting the retreat and at the time of completion of discharge to the surface where the valve block and the cylinder block are joined, the minimum amount of liquid required can be stored without storing excess liquid in the plunger chamber. It becomes possible to pressurize.

Further, since the pressure is applied to the minimum necessary amount of liquid, the liquid is ejected from the tip of the nozzle according to the operation of the plunger, and for example, from the nozzle ejection port although the plunger is stopped after the completion of ejection. The liquid does not continue to be discharged slowly, the delay of the discharge completion due to the expansion of the compressed liquid and the liquid sag can be eliminated, and the liquid can be controlled with high responsiveness. Further, by keeping the liquid suction start position and the liquid discharge completion position at the tip of the plunger at a constant position in this way, the amount of liquid to be pressurized is constant from the plunger tip to the nozzle tip. Therefore, the compression amount of the pressure buffer is always a constant amount, and therefore, the liquid amount for each ejection is stable and accurate ejection is possible.

Further, since one discharge is performed by one advance movement of one plunger, the liquid discharged from the nozzle tip has no pulsation. Moreover, since all the liquid sucked into the plunger chamber is discharged from the plunger chamber,
There is no liquid that stays near the plunger, and the liquid that has stayed for a long time does not denature in the plunger chamber. For example, the adhesive will not solidify and the plunger and plunger chamber will not be fixed.

As described above, when the pump portion and the valve portion are arranged so as to be connected to each other and the tip end position of the plunger is on the surface where the valve block and the cylinder block are joined, the suction start and the discharge can be completed. Therefore, it is possible to pressurize the minimum necessary amount of liquid without compressing the excess amount of liquid, and it is possible to control the liquid with high responsiveness, and therefore it is possible to discharge with high-speed tact. Further, since the plunger tip position is always constant for each discharge, it is possible to discharge with high precision. In the present invention, it goes without saying that the suck back operation can be performed by adjusting the stop position of the plunger by the control means.

[0032]

The details of the present invention will be described with reference to Examples. The present invention is not limited to these examples.

Embodiment 1 Referring to FIGS. 1 and 2, one embodiment of the present invention will be described. In the drawing, reference numeral 31 denotes a block-shaped metal material and a plunger chamber A3.
1a, a cylinder block having a cylindrical through hole forming a plunger chamber B31b. Plunger room A31
a, Plunger rod A27 in plunger chamber B31b
The plunger rod B28 is fitted in such a manner that it can move back and forth, and the stroke of each plunger rod is set so that the front end surface of the plunger rod at the most forward position is flush with one side surface of the cylinder block 31. A valve block 34 is disposed on one side surface of the cylinder block 31 having the opening of the through hole so as to be in close contact with and in sliding contact with the cylinder block 31, and the valve block 34 is pressed against the cylinder block 31 by a pressing member 35. Prevents leakage of liquid between both blocks. Incidentally, reference numerals 29 and 30 in the drawing are seal portions for preventing liquid from leaking from between the cylinder block and the plunger rod.

A flow path is formed in the valve block 34 as shown in the figure. The valve block 34 constitutes a slide valve together with the cylinder block 31, and opens and closes the flow path between the storage container 1 and the nozzle 2 to open the nozzle 2 Control the liquid supplied to. Further, a portion of the surface of the valve block 34, which is in pressure contact with the cylinder block 31, in which the flow path is not open functions as a cylinder head. That is, the slide valve is the valve block 34.
And the cylinder block 35, so that the plunger chamber B31b and the nozzle 2 communicate with each other when the plunger chamber A31a and the storage container 1 are connected, and the plunger chamber B31b and the storage chamber when the plunger chamber A31a and the nozzle 2 communicate with each other. Based on a signal from the air control means 10, the valve block 34 slides with respect to the cylinder block 31 to perform switching operation so that the container 1 communicates.

Further, since the valve block 34 is in pressure contact with the pushing member 35 and the cylinder block 31, in order to smooth the sliding of the valve block 34, the pushing force of the pushing member 35 of the valve block 34 is reduced. It is preferable to reduce the friction coefficient of the contact surface of (1) and the contact surface with the cylinder block 31, and specifically, the contact area can be reduced.

The motor A20 is connected to the ball screw A23 via a gear A21. Plunger rod A2
7 is the plunger chamber A31 by the rotation operation of the motor A20.
It is attached to the plunger rod mounting plate A25 so as to be inscribed in a and move forward and backward. The plunger rod B28 is inscribed in the plunger chamber B31b by the rotation of the ball screw B24 so that the plunger rod B28 moves back and forth.
Gear B22 connected to the ball screw B24 so that the plunger rod B28 moves backward when the plunger rod A27 moves forward, and the plunger rod B28 moves forward when the plunger rod A27 moves backward. Is gear A2
It is connected to 1.

The pushing member 35 at the tip of the air cylinder A36 is
Since the cylinder block is pressurized and fixed by the air pressure supplied from the air control means 10, the valve block 3
4 is in close contact with the cylinder block 31 and the pressing member 35 and can relatively slide, thereby preventing unnecessary leakage of liquid. When a constant air pressure is constantly supplied from the air control means 10, the air cylinder A
The pressing member 35 at the tip of 36 can always bring the valve block 34 and the cylinder block 31 into contact with each other with a desired force. If a spring or the like is used as the pressing force, the force for holding down the valve block 34 is displaced due to alteration or deformation of the material or the like, which is not preferable. Furthermore, the air cylinder A
By using 36, even if the contact surface between the valve block 34 and the cylinder block 31 is worn and the width of the valve block 34 becomes small, the air pressure adjusted to a constant pressure is supplied to the air cylinder A36. Therefore, the valve block 34 can be brought into contact with the cylinder block 31 with the same force as before wear, and no gap is generated on the contact surface between the valve block 34 and the cylinder block 31, so that unnecessary liquid is not generated. Can be prevented from leaking.

A stopper is attached to the air cylinder A36, and when a force is applied to the valve block 34 in a direction away from the cylinder block 31, the air cylinder A36
The valve block 34 and the cylinder block 31 can be prevented from separating from each other. The valve block 34 slides parallel to the contact surface with the cylinder block 31, so that the plunger chamber B31b communicates with the storage container 1 when the plunger chamber A31a communicates with the nozzle 2, and the plunger chamber B31b communicates with the nozzle 2.
The position is controlled so that the plunger chamber A31a communicates with the storage container 1 when communicating with the storage container 1. This sliding motion is
This can be performed by controlling the air cylinder B37 by the air control means 10.

2 connected to both ends of the air cylinder B37
The valve block 34, which has the same width as the distance between the arms of the two valve block support arms 33, is sandwiched between the two support arms 33, and the valve block 34 is slid.

The valve block 34 is not adhesively fixed, but the valve block support arm 33 of the air cylinder B37 and the pushing member 35 of the air cylinder A36.
Since the pressure supply to the air cylinder A36 is cut off and the pressing member 35 reduces the pressure applied to the valve block 34, the valve block 3 can be easily pressed.
4 can be removed, facilitating replacement when the valve block 34 wears.

The motor B38 is connected to the ball screw C39, and the relative distance between the base block 49 and the sub block 50 is changed by the ball screw C3 by the rotating operation of the motor B38.
It can be changed in 9 axial directions.

The base block 49 has a motor A20,
A ball screw A23, a ball screw B24, a plunger rod A27, a plunger rod B28, a plunger rod mounting plate A25, and a plunger rod mounting plate B26 are fixed, and the sub block 50 has a plunger chamber A31.
Since a, the plunger chamber B31b, the cylinder block 31, the nozzle 2 and the valve block 34 are fixed, by moving the relative distance between the base block 49 and the sub block 50 by the rotation of the ball screw C39,
Plunger rod A27 and plunger rod B28
Plunger rod A27 while keeping the relative distance between
Since the relative distance between the plunger rod B28 and the valve block 34 can be adjusted, the plunger rod position can be brought close to the valve block 34 when the plunger rod that performs a small amount of discharge is displaced only slightly, which is unnecessary. It is possible to effectively remove the residual liquid in the cylinder.

When the center of the maximum stroke amount of the plunger rod moving forward and backward is the position where the tip of the plunger rod A27 and the tip of the plunger rod B28 are aligned, when discharging an amount that does not require the maximum stroke,
For example, when a small amount is discharged, the advancing / retreating operation is performed only a small amount as compared with the maximum stroke amount of the plunger rod. At this time, since the liquid from the tip end position of the plunger rod to the valve block 34 at the end of the discharge acts as a buffer, it is preferable that the liquid serving as the buffer is particularly removed when the discharge is performed by high-speed tact.

Liquid can be replenished to the storage container 1 as appropriate. It is also possible to replace it with another storage container 1 in which the liquid is stored. The air cylinder A36 and the air cylinder B37 are connected to the air control means 10,
Air can be supplied as needed. Further, the air control unit 10, the motor A20, and the motor B38 are connected to the control unit 11 and operate based on a signal from the control unit 11.

The discharge work is carried out by (1) adjusting the tips of the plunger rod A27 and the plunger rod B28 to positions equidistant from the cylinder block (positions aligned). This position is the base position. (2) The plunger rod A27 is moved forward by driving the motor A1 by a volume amount which is half the desired discharge amount. At this time, the rotation of the motor A1 is performed so that the plunger rod B28 moves backward by a volume amount which is half the desired discharge amount.
It is transmitted to gear B22 via 21. (3) Since the amount of advancement of the plunger rod A27 from the reference position at this time is the maximum when the desired amount is discharged, the motor is moved so that the tip end position of the plunger rod A27 approaches the valve block 34. B
38 is driven to adjust the relative distance between the base block 49 and the sub block 50 so that the remaining amount of liquid in the plunger chamber A31a is minimized, preferably zero.
By driving the motor B, the plunger rod A27 and the plunger rod B28 move in translation integrally,
The relative distance between the plunger rod A27 and the plunger rod B28 does not change.

(4) Here, the storage container and the plunger chamber A
The position of the valve block 34 is adjusted so that the nozzle 2 and the plunger chamber B31b communicate with each other. (5) Next, the plunger rod B28 is moved forward by driving the motor A20 by the desired discharge volume amount. At this time, the rotation of the motor A20 causes the plunger rod A27 to move backward by the desired discharge volume amount, so that the liquid in the storage container 1 is sucked into the plunger chamber A31a. (6) Further, the storage container 1 and the plunger chamber B31b are communicated with each other, that is, the nozzle 2 and the plunger chamber A3.
The position of the valve block 34 is adjusted so that 1a communicates. (7) The plunger rod A27 is moved forward by driving the motor A20 by the desired discharge volume amount. Plunger room A
Since 31a was filled with a desired amount of liquid, the liquid is ejected from the ejection port at the tip of the nozzle 2 by driving the motor A20. In addition, the storage container 1 and the plunger chamber B31
b communicates with each other, and at this time, the plunger rod B28 moves backward by the desired discharge volume amount by the rotation of the motor A20, so that the liquid in the storage container 1 is sucked into the plunger chamber B31b. (8) The liquid is ejected by the following 4 to 7 operations.

As described above, the ejection is performed by the advance of the one plunger rod, and at the same time, the other plunger rod sucks the liquid into the plunger chamber, so that the ejection work can be performed with a high-speed tact.

Embodiment 2 In Embodiment 1 described above, the two plunger rods are driven by the single motor, but in this embodiment, the motors 60 and 61 are respectively provided to the two plunger rods 27 and 28.
Is connected to the plunger chamber A3.
This is an example in which pneumatic pressure is applied to the liquid in the storage container 1 so that the liquid can be quickly filled in the liquids 1a and B31b, and the main features are as follows.

(1) Since the motors 60 and 61 are connected to the two ball screws 23 and 24, respectively, the two plunger rods 27 and 28 can be independently moved. This makes it possible to change the discharge and inhalation speeds, so it is possible to slow down the filling speed without changing the ejection speed in liquids that require a long time to inhale, which is not suitable for liquids. It is possible to suppress the occurrence of cavitation and the like without applying force.

(2) Two independent motors 60, 6
By rotating 1 in the same direction, the relative distance between the plunger rod A27 and the plunger rod B28 and the valve block 34 can be adjusted while keeping the relative distance between the plunger rod A27 and the plunger rod B28 constant. In No. 2, it is unnecessary to separate the base block and the sub-block as shown in FIG. 3 and slide them by the motor.

(3) From the storage container 1 to the plunger chamber A31
Since the air inside the storage container 1 can be pressurized by the air control means 10 so that the liquid can be quickly sucked into the a and B31b, the liquid can be supplied to the plunger chamber at a high speed, and the speed can be increased. Discharge work can be performed at the takt time. The effect is great when ejecting a high-viscosity liquid. In the present invention, the storage container and the cylinder block can be communicated with each other via a liquid feeding tube. In this case, since the storage container and the apparatus main body can be installed at positions separated from each other, the storage container can be easily replaced even if the apparatus main body is installed at a position where the operator cannot reach. . Similarly, it is also possible to connect the valve block and the nozzle via a liquid feeding tube.

Embodiment 3 In Embodiments 1 and 2 described above, a slide type switching valve is used as the switching valve, but in this example, a rotary type switching valve having a smooth sliding surface is used as the switching valve, and a cylinder is used. A hole that communicates with the pump section provided on the surface of the cylinder block that is in close contact with the valve block by rotating the disk-shaped valve body that has an arcuate flow path on the surface that contacts the block in one direction or by repeatedly rotating it. And a hole communicating with the liquid storage container provided on the contact surface, and a hole communicating with the nozzle provided on the contact surface, by the arc-shaped flow path provided on the disc-shaped valve body,
A switching operation is performed between a state in which the pump portion and the liquid storage container communicate with each other and a state in which the pump portion and the nozzle communicate with each other, and the first embodiment
Alternatively, as in the case of 2, the flow path is switched.

Although all of the above-mentioned embodiments have been described as having two pump parts, the present invention uses one pump part.
It is also possible to configure the liquid flow path so as to connect the plunger chamber and the liquid storage container or to connect the plunger chamber and the nozzle. Also, although the plunger chamber was directly drilled in the cylinder block, a separate cylinder can be fitted into the mounting hole drilled in the cylinder block to form the plunger chamber. Alternatively, a separate cylinder may be fitted into a mounting hole formed in the cylinder block to form a plunger chamber, and the sliding surface that comes into close contact with the valve portion may be formed of a hard member. Even if the plunger chamber is formed directly in the cylinder block, the surface of the cylinder block that comes into contact with the valve portion is heavily worn, so the sliding surface that is in close contact with the valve portion may be formed of a hard member.

[0054]

As described above, since the pump portion and the valve portion are arranged so as to be connected to each other and the most advanced position of the plunger is the surface where the front end face of the plunger is joined to the valve portion and the pump portion, the surplus It is possible to pressurize the minimum necessary amount of liquid without compressing a certain amount of liquid, and it is possible to control the liquid with high responsiveness, and therefore it is possible to discharge with high-speed tact. Further, since the plunger tip position is always constant for each discharge, it is possible to discharge with high precision.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a first embodiment.

FIG. 2 is an enlarged view of a main part of the first embodiment.

FIG. 3 is a schematic diagram of a second embodiment.

[Explanation of symbols]

1 Storage container 2 nozzles 10 Air control means 11 Control unit 20 Motor A 21 Gear A 22 Gear B 23 Ball screw A 24 Ball screw B 25 Plunger rod mounting plate A 26 Plunger rod mounting plate B 27 Plunger rod A 28 Plunger rod B 29 Seal part 30 Seal part 31 cylinder block 31a Plunger room A 31b Plunger room B 32 Storage container mounting port 33 Support arm 34 Valve block 35 Push member 36 Air cylinder A 37 Air cylinder B 38 Motor B 39 Ball screw C 40 Liquid Delivery Tube A 41 Air cylinder B Air tube mounting port 1 42 Air cylinder B Air tube mounting port 2 43 Air tube C 44 Air tube D 45 Air cylinder A Air tube mounting port 1 46 Air cylinder B Air tube mounting port 2 47 Air Tube E 48 Air tube F 49 base block 50 sub-blocks 60 Motor C 61 Motor D

Continued front page    F term (reference) 3H071 AA01 AA15 BB13 CC11 CC17                       CC37 CC47 DD01 DD06 DD11                       DD42 DD72                 3H075 AA01 AA12 AA17 BB02 BB13                       BB16 BB30 CC11 CC30 CC36                       DA03 DA04 DA07 DB03 DB22                 4F041 AA06 AB02 BA02 BA05 BA10                       BA32 BA34 BA35                 4F042 AA07 BA12 CA01 CB02 CB07                       CB08 CB11 CB18 CB24

Claims (10)

[Claims] 1. A pump unit comprising a plunger chamber bored in a cylinder block and a plunger reciprocating in the plunger chamber, a pump unit for measuring a desired amount of liquid to be discharged, and a valve unit for switching a liquid passage for suction and discharge. A storage section that stores fluid, and a discharge section that has a discharge port that discharges the liquid;
In the above configuration, the pump portion and the valve portion are connected to each other, and the most advanced position of the plunger is the surface where the front end face of the plunger is joined to the valve portion and the pump portion. apparatus. 2. The liquid constant-quantity discharge device according to claim 1, wherein the valve portion is detachably disposed on the pump portion. 3. The plunger chamber comprises a cylindrical member mounted in a hole formed in the cylinder block.
Quantitative discharge device for any of the liquids. 4. The switching valve according to claim 1, wherein the valve portion is a switching valve including a valve block having a first flow passage communicating with the storage container and a second flow passage communicating with the discharge portion. Liquid dispensing device. 5. The liquid quantitative dispensing device according to claim 1, wherein the switching valve is a slide type switching valve. 6. The liquid constant-volume discharge device according to claim 1, wherein the switching valve is a rotary switching valve having a smooth sliding surface. 7. A slide valve, which is brought into close contact with a cylinder block by applying a pressure, is provided.
Or a liquid constant-quantity discharge device according to any one of 6 above. 8. The liquid quantitative discharge device according to claim 1, further comprising a pressurizing means for pressurizing the liquid in the storage container. 9. The liquid constant-quantity discharge device according to claim 1, wherein a plurality of pump parts are provided, and a plurality of plungers constituting the pump part are driven by a single drive source. 10. The liquid constant-quantity discharge device according to claim 1, wherein a plurality of pump parts are provided and a plurality of plungers forming the pump part are driven by independent drive sources.