JP4136477B2 - Liquid dispensing device - Google Patents

Description

[0001]
[Technical field to which industry belongs]
The present invention discharges liquids of all viscosities, for example, low viscosity substances such as water and alcohol, to high viscosity fluids such as adhesives, pastes, or creamy industrial materials at high speed and with high accuracy. Method and apparatus.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a device that discharges liquid in a fixed amount, (1) Air is applied to a liquid in a storage container for a desired time, and a desired amount of liquid is discharged from a discharge port at the tip of the nozzle. (2) Plunger-type discharge device that pressurizes the liquid by moving a liquid-tight plunger to the liquid in the storage container and discharges a desired amount of liquid from the discharge port at the tip of the nozzle. 3) A cylinder is provided between the storage container and the nozzle, and a plurality of through holes provided in the cylinder are provided so that one plunger is advanced and retracted in one through hole. In the mechanism in which the liquid is sucked into the cylinder and the liquid is discharged from the cylinder to the nozzle by the forward movement of the plunger, the plurality of plungers act on the liquid in order to pressurize the liquid, Discharging a 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]
[Problems to be solved by the invention]
However, with these techniques, it has been impossible to discharge with high accuracy and high quantitativeness while maintaining a fast tact time as currently required.
For example, in the die bonding process in semiconductor manufacturing, it is required to discharge a large amount in a short time due to the appearance of large-sized devices with high performance and the demand for higher tact to improve productivity. On the other hand, since a high-quality product is required, high-precision discharge and fine coating are required.
In order to satisfy such a requirement, the conventional techniques have problems.
[0004]
For example, (1) Air type discharge device uses air pressure as a pressure source for discharging liquid, but since air pressure is rich in compressibility, it is very difficult to change the pressure greatly in a short time, so high speed It was unsuitable to discharge with a short tact.
Even when a large amount of liquid is discharged in a short time and particularly when the liquid to be discharged is a high-viscosity liquid agent, it is necessary to apply a high pressure to the liquid. Therefore, there is a limit to shortening the discharge time, and there is a problem that the discharge cannot be performed with high-speed tact.
[0005]
The plunger-type discharge device (2) is a method in which a plunger disposed in a liquid-tight manner near the liquid head in the storage container pressurizes and discharges all the stored liquid. Here, since the amount of liquid to be pressurized depends on the amount of residual liquid in the storage container, the desired pressure arrival time when the liquid agent is pressurized to a desired pressure is fast when the residual liquid amount is small, If there is a large amount of residual liquid, it will be slow. Thus, since the pressure change at the time of discharge differs depending on the amount of remaining liquid in the storage container, there is a problem that the discharge amount varies due to this.
If the amount of liquid stored in advance is set to a small amount, an operation of exchanging the storage container at a short cycle is required, resulting in a problem that work efficiency deteriorates.
[0006]
(3) In the multiple plunger pump type discharge device, since a plurality of plungers sequentially pressurizes the liquid, when the control shifts from one plunger to the other plunger, the liquid is Since the pressure is simultaneously applied by the two plungers, the applied force is not uniform, and thus there is a problem in that the pulsation is generated in the discharged liquid and the flow velocity is not uniform.
For this reason, if liquid is applied and drawn on the workpiece in a linear shape with this device, unevenness and distortion occur in the line width and line height, and a uniform application shape cannot be formed. In this case, it is substantially impossible to form the coating.
[0007]
An object of the present invention is to provide a discharge method and apparatus for discharging a liquid at high speed and with high accuracy by solving these problems concerning high-speed and high-precision quantitative discharge of the liquid.
[0008]
[Means for Solving the Problems]
The present invention comprises a plunger chamber bored in a cylinder block and a plunger that reciprocates in the plunger chamber, a pump unit that measures the amount of liquid to be discharged to a desired amount, a valve unit that switches between suction and discharge liquid flow paths, In a configuration with a storage part for storing liquid and a discharge part having a discharge port for discharging liquid, which can communicate with the pump part depending on the position of the valve part, the pump part and the valve part are connected to each other, and The gist of the liquid dispensing apparatus is characterized in that the most advanced position of the plunger is the surface where the front end surface of the plunger is joined to the valve portion and the pump portion.
[0009]
The valve section is a 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 section. In this case, the present invention provides a desired amount of liquid to be discharged. A pump section for metering the liquid, a valve section for switching the liquid flow path for suction and discharge, a storage section for storing the liquid that can communicate with the pump section according to the position of the valve section, and a discharge section having a discharge port for discharging the liquid In the configuration of the above, the above-described pump unit is configured by a cylinder block equipped with a cylinder having a plunger, and the above-described valve unit is connected to the first flow path communicating with the storage container and the second flow communicating with the discharge unit. The gist of the liquid dispensing device is characterized in that it is a switching valve having a valve block having a passage, and the pump part and the valve part are connected to each other.
[0010]
The above-described switching valve is a slide-type switching valve. In this case, the present invention provides a pump unit that measures the amount of liquid to be discharged to a desired amount, a valve unit that switches a suction and discharge liquid flow path, In the configuration of the storage part that stores the liquid that can communicate with the pump part depending on the position, and the discharge part that includes the discharge port that discharges the liquid, the pump part is configured by a cylinder block in which a cylinder having a plunger is mounted. The above-described valve unit is a slide-type switching valve having a valve block having a first channel communicating with the storage container and a second channel communicating with the discharge unit, and a pump unit The gist of the liquid dispensing apparatus is characterized in that the valve portions are connected to each other.
[0011]
The cylinder block and the valve block are arranged so as to be in close contact with each other, and the pump unit and the valve unit are arranged to be connected. In this case, the present invention measures the liquid to be discharged to a desired amount. By the pump unit, the valve unit for switching the liquid flow path for suction and discharge, the storage unit for storing the liquid that can communicate with the pump unit depending on the position of the valve unit, and the discharge unit having a discharge port for discharging the liquid In the configuration, the pump unit is configured by a cylinder block to which a cylinder having a plunger is attached, the first flow path communicating with the storage container, and the second flow path communicating with the discharge section. A rotary type switching valve having a sliding block, a one-way rotating type, or a reciprocating smooth sliding surface, and a cylinder block and a valve block. It is summarized as dispensing system for a liquid, characterized in that arranged by connecting the pump unit and the valve unit by disposing in close contact and sliding fit and.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the method of quantitative dispensing of liquid, in which the liquid is sucked from the storage container into the plunger chamber by the retreating operation of the plunger, and the liquid is discharged from the plunger chamber to the nozzle by the advancement operation of the plunger, It is characterized by performing the operation and one discharging operation. Since the liquid is not pressurized by a plurality of plungers at the same time, the applied pressure applied to the liquid is constant, so that no pulsation occurs in the discharged liquid and the flow rate becomes uniform. For this reason, even if the liquid is applied and drawn on the workpiece in a linear shape, the width and height of the line are not uneven or distorted, and a uniform applied shape can be formed, and a high-definition pattern shape can be applied. Can be formed. Furthermore, since one discharge is performed by one movement of the plunger, there is no pulsation in the discharged liquid, and it is possible to discharge the liquid at a constant flow rate. It can be finely applied and formed.
[0013]
Moreover, since the discharge means that the liquid flows out from the nozzle due to the pressure difference between the liquid induced by pressurizing the liquid and the atmospheric pressure, the liquid is pressurized in order to effectively induce the pressure difference. The smaller the volume of the liquid, the better. The liquid pressure can be increased more steeply, which is effective when a large amount of liquid is discharged in a short time and particularly when the liquid to be discharged is a high-viscosity liquid agent. Therefore, it is preferable to pressurize a single discharge amount by sucking the liquid into the plunger chamber rather than pressurizing a liquid amount corresponding to a plurality of discharge amounts. More preferably, there is no remaining liquid in the plunger chamber after completion of the plunger liquid discharge. 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 furthermore, it is possible to greatly shorten the time from the pressurization of the liquid until the liquid is discharged from the nozzle, thereby enabling high-speed discharge. .
[0014]
Here, it is preferable that the liquid suction start position and the liquid discharge end position of the plunger are made equal for each discharge. Making the amount of liquid to be pressurized at each discharge constant 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 at the time of discharge pressurizes the liquid Since the process of increasing the amount can be made equal for each discharge, there is no variation in the discharge amount depending on the remaining 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 high-precision 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.
[0015]
A specific device configuration includes a nozzle for discharging liquid, a storage container for storing liquid, a cylinder block having a plunger chamber therein, a plunger inscribed and retracted in contact with the plunger chamber, and drive means for driving the plunger And a switching valve that communicates the plunger chamber with the storage container or nozzle. In this device, the plunger connected to the driving means moves forward and backward in contact with the inner wall, the plunger moves backward by an amount equal to the discharge amount, sucks liquid from the storage container into the plunger chamber, and the plunger is equal to the discharge amount. The liquid is discharged by discharging the liquid from the plunger chamber to the nozzle by moving forward only. At this time, the switching valve communicates the plunger chamber and the storage container when the plunger moves backward to suck the liquid into the plunger chamber, and when the plunger moves forward and discharges the liquid from the plunger chamber, the plunger chamber and the nozzle are connected. Operates to communicate.
[0016]
By connecting the storage container and the switching valve via the liquid feed pipe, the liquid agent storage part and the discharge mechanism part can be separated, so that the storage container can be disposed in an easy-to-handle place, for example, When the remaining amount of the liquid in the storage container is reduced, it is possible to easily perform the operation of replenishing the liquid storage container with the liquid or replacing the storage container filled with the liquid in advance. Furthermore, the amount of liquid stored in the container can be stored in a planned manner, considering the pot life of the liquid to be used and the daily work amount. It is possible to dispense with the replenishment work or to replenish appropriately.
[0017]
Further, since the discharge mechanism and the discharge port can be separated by communicating the nozzle and the switching valve via the liquid feed pipe, the discharge mechanism is installed in the fixed part, and the nozzle is moved to the movable part, for example, a robot. Therefore, the movable part can be made extremely lightweight. This makes it possible to carry out a coating operation, for example, a drawing operation for applying a desired pattern shape on the workpiece surface at a very high speed.
[0018]
When the liquid in the storage container is a highly viscous fluid, or when the liquid is quickly sucked into the plunger chamber, the suction force by the backward movement of the plunger is assisted to feed the liquid in the storage container into the plunger chamber. In order to do so, it is preferable to provide a pressurizing device for pressurizing the liquid in the storage container.
[0019]
The switching valve can be a slide type switching valve. Preferably, the switching valve is a slide valve having a first flow path that communicates with the storage container and a second flow path that communicates with the nozzle, and a valve block that slides and switches a portion that communicates. As the first flow path and the second flow path are adjacent to each other, the loss time at the time of switching can be shortened and the discharge can be performed with a high tact time.
[0020]
The driving means and / or the switching valve can operate based on a signal from the control unit. Preferably, the switching valve is controlled so that the plunger communicates with the nozzle at the time of discharge, the driving means is controlled to pressurize the liquid, and the suction valve is controlled so that the plunger communicates with the storage container at the time of suction. Further, the driving means is controlled to suck the liquid.
[0021]
The number of plungers can be plural. At this time, since a plurality of discharges can be performed with different plungers each time, in the discharge operation of any one of the plungers, the other plunger is sucked or stopped, so that the liquid is discharged at the next discharge. Since the sucked plunger can quickly discharge the liquid, the time required for effectively sucking the liquid can be made unnecessary, and a faster tact time can be achieved.
[0022]
Furthermore, it is possible to make the drive means equal to the number of plungers.
Further, the plunger can be controlled independently. 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 preferable that one of the plurality of plungers is suitable for discharging when the plunger is engaged in discharging, and is preferable for suction when engaging in the suction.
[0023]
Furthermore, the liquid ejection device of the present invention communicates the nozzle that ejects the liquid, the storage container that stores the liquid, the plunger pump, the driving means that drives the plunger pump, the plunger chamber, and the storage container or nozzle. A switching valve is provided, and a cylinder block constituting the plunger pump and a valve block constituting the switching valve are arranged so as to be in close contact with each other and to slide together. When the pump unit and the valve unit are connected and the tip of the plunger is on the surface where the valve block and the cylinder block are joined, the suction operation is started and the discharge operation is completed. Without compressing the amount of liquid, it becomes possible to pressurize the minimum amount of liquid, and the liquid can be controlled with high responsiveness. Since the position is always constant for each discharge, it is possible to discharge with high accuracy.
[0024]
Therefore, liquid discharge and suction are switched by the forward / backward movement of the plunger, which is a component part of the pump unit, and the movement of the valve block, which is a component part of the valve unit, and the position of the valve block, which is a component part of the valve unit. When the pump unit and the liquid storage unit 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 moves the plunger to the position where the backward movement starts. Advance The nozzle is moved so that the liquid is discharged from the tip of the nozzle. At this time, the position of the tip of the plunger at the start of the retraction and at the completion of the discharge is the surface where the valve block and the cylinder block are joined.
[0025]
Here, the liquid is slightly compressible, but pressurizes to reduce the volume. That is, in order to pressurize the liquid, it is necessary to compress the liquid, and it becomes difficult to cause a steep pressure increase as the amount of liquid to be pressurized increases. For example, in this apparatus, the more the amount of liquid to be pressurized, the more the pressure increase process becomes equal unless the plunger moving speed is increased. That is, if the amount of liquid to be compressed is small, the pressure can be increased with a small amount of plunger movement. Therefore, by setting the tip position of the plunger at the start of retraction and at the completion of discharge as the surface where the valve block and the cylinder block are joined, excess liquid is not stored in the plunger chamber, and the necessary minimum amount of liquid is stored. It becomes possible to pressurize.
[0026]
In addition, since pressure is applied to the minimum required amount of liquid, the liquid is discharged from the nozzle tip according to the operation of the plunger. For example, the liquid is gently discharged from the nozzle discharge port even though the plunger is stopped after completion of the discharge. Thus, the discharge completion delay due to the expansion of the compressed liquid, and the liquid sag can be eliminated, and the liquid can be controlled with high responsiveness.
In addition, by constantly setting the liquid suction start position and the liquid discharge completion position at the plunger tip in this way, the amount of liquid to be pressurized from the plunger tip to the nozzle tip is also constant. Therefore, the compression amount of the pressure buffer is always a constant amount, so that the liquid amount for each discharge is stable and accurate discharge is possible.
[0027]
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 does not solidify and the plunger is not fixed.
[0028]
[Action]
The discharge and suction of the liquid 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 the component of the valve unit, and the position of the valve block is in communication with the pump block. The plunger moves backward to a position corresponding to the discharge amount, sucks the liquid from the storage container by the amount to be discharged into the plunger chamber, and then moves the valve block to a position where the pump unit and the nozzle unit communicate with each other. Then, the plunger is moved forward to the position where the backward movement is started, and the liquid is discharged from the tip of the nozzle. At this time, the tip position of the plunger at the start of retraction and at the completion of discharge is defined as a surface where the valve block and the cylinder block are joined.
Therefore, by setting the tip position of the plunger at the start of retraction and at the completion of discharge as the surface where the valve block and the cylinder block are joined, excess liquid is not stored in the plunger chamber, and the necessary minimum amount of liquid is stored. It becomes possible to pressurize.
[0029]
In addition, since pressure is applied to the minimum amount of liquid, liquid is discharged from the nozzle tip according to the operation of the plunger. For example, the liquid is gently discharged from the nozzle discharge port even though the plunger is stopped after completion of discharge. Thus, the discharge completion delay due to the expansion of the compressed liquid, and the liquid sag can be eliminated, and the liquid can be controlled with high responsiveness.
In addition, by constantly setting the liquid suction start position and the liquid discharge completion position at the plunger tip in this way, the amount of liquid to be pressurized from the plunger tip to the nozzle tip is also constant. Therefore, the compression amount of the pressure buffer is always a constant amount, so that the liquid amount for each discharge is stable and accurate discharge is possible.
[0030]
Furthermore, 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 does not solidify and the plunger and the plunger chamber are not fixed.
[0031]
In this way, since the pump portion and the valve portion are connected and disposed, and when 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 discharge can be completed. Without compressing the amount of liquid, that is, it is possible to pressurize the minimum necessary liquid, and the liquid can be controlled with high responsiveness, and therefore, it can be discharged at high speed.
Further, since the plunger tip position is always constant for each discharge, it is possible to discharge with high accuracy.
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]
【Example】
The details of the present invention will be described in Examples. The present invention is not limited to these examples.
[0033]
Example 1
An embodiment of the present invention will be described with reference to FIGS.
In the figure, reference numeral 31 denotes a cylinder block having a cylindrical through-hole formed in the block-shaped metal material to form the plunger chamber A31a and the plunger chamber B31b. A plunger rod A27 and a plunger rod B28 are fitted in the plunger chamber A31a and the plunger chamber B31b so as to be able to advance and retreat. The front end surface of the plunger rod in the most advanced position is the one side surface of the cylinder block 31. And is set to be flush with each other. A valve block 34 is disposed on one side surface of the cylinder block 31 having the opening of the through hole so that the valve block 34 is in close contact with and slid, and the valve block 34 is pressed against the cylinder block 31 by a pressing member 35. Prevents leakage of liquid between both blocks.
In the figure, 29 and 30 are seal portions for preventing liquid from leaking from between the cylinder block and the plunger rod.
[0034]
The valve block 34 is formed with a flow path as shown in the figure, forms a slide valve with the cylinder block 31, opens and closes the flow path between the storage container 1 and the nozzle 2, and supplies it to the nozzle 2. Control the liquid. Further, the portion of the valve block 34 that is in pressure contact with the cylinder block 31 functions as a cylinder head. That is, the slide valve is constituted by the valve block 34 and the cylinder block 35, and the plunger chamber B31b and the nozzle 2 communicate with each other when the plunger chamber A31a and the storage container 1 are coupled, and the plunger chamber A31a and the nozzle 2 communicate with each other. In doing so, the valve block 34 is slid and switched with respect to the cylinder block 31 based on a signal from the air control means 10 so that the plunger chamber B31b and the storage container 1 communicate with each other.
[0035]
Further, since the valve block 34 is in pressure contact between the push member 35 and the cylinder block 31, in order to smooth the sliding of the valve block 34, the contact surface of the valve block 34 with the push member 35. The contact surface with the cylinder block 31 preferably has a low coefficient of friction. Specifically, the contact surface can be reduced by reducing the contact area.
[0036]
The motor A20 is connected via a ball screw A23 and a gear A21.
The plunger rod A27 is attached to the plunger rod mounting plate A25 so as to move inward and backward with respect to the plunger chamber A31a by the rotation operation of the motor A20.
The plunger rod B28 is attached to the plunger rod mounting plate B26 so that the plunger rod B28 is moved inward and backward by rotating the ball screw B24, and when the plunger rod A27 moves forward, the plunger rod B28 moves backward. The gear B22 connected to the ball screw B24 is connected to the gear A21 so that the plunger rod B28 moves forward when the plunger rod A27 moves backward.
[0037]
Since the push member 35 at the tip of the air cylinder A36 presses and fixes the cylinder block by the air pressure supplied from the air control means 10, the valve block 34 is in close contact with the cylinder block 31 and the push member 35, and is relatively Thus, it is possible to prevent the unnecessary liquid from leaking.
When a constant air pressure is always supplied from the air control means 10, the push member 35 at the tip of the air cylinder A36 can always bring the valve block 34 and the cylinder block 31 into contact with each other with a desired force. The use of a spring or the like as the applied pressure is not preferable because the force that holds the valve block 34 is displaced due to alteration or deformation of the material.
Furthermore, the use of the air cylinder A36 means that 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 is reduced, the air pressure adjusted to a constant pressure is reduced. Since it is supplied to the cylinder A36, the valve block 34 can be brought into contact with the cylinder block 31 with the same force as before the wear, and no gap is generated on the contact surface between the valve block 34 and the cylinder block 31. It is possible to prevent leakage of unnecessary liquid.
[0038]
A stopper is attached to the air cylinder A36 to prevent the air cylinder A36 from being retracted when a force is applied to the valve block 34 in a direction away from the cylinder block 31, so that the valve block 34 and the cylinder block 31 are not separated. You can also
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.
This sliding operation can be performed by the air control unit 10 controlling the air cylinder B37.
[0039]
A valve block 34 formed with the same width as the distance between the arms of the two valve block support arms 33 connected to both ends of the air cylinder B37 is sandwiched between the two support arms 33, and the valve The block 34 is slid.
[0040]
The valve block 34 is not adhesively fixed, but is merely pressure-fixed to the valve block support arm 33 of the air cylinder B37 and the pressing member 35 of the air cylinder A36. When the pressure supply is cut off and the pressing member 35 reduces the pressurization of the valve block 34, the valve block 34 can be easily removed and the replacement when the valve block 34 is worn is facilitated.
[0041]
The motor B38 is connected to the ball screw C39, and the relative distance between the base block 49 and the sub block 50 can be changed in the axial direction of the ball screw C39 by the rotation operation of the motor B38.
[0042]
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 to the base block 49, and a plunger chamber A31a and a plunger are fixed to the sub block 50. Since the chamber B31b, the cylinder block 31, the nozzle 2 and the valve block 34 are fixed, the plunger rod A27 and the plunger rod B28 are moved by moving the relative distance between the base block 49 and the sub block 50 by the rotation of the ball screw C39. Since 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 constant, the plunger rod that performs a small amount of discharge is slightly displaced. If stomach, the plunger rod position it is possible to close the valve block 34, the unnecessary liquid can be effectively removed that remains in the cylinder.
[0043]
When the center of the maximum stroke amount that the plunger rod moves 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 discharging a minute amount Moves forwards and backwards by a small amount compared to the maximum stroke of the plunger rod. At this time, the liquid from the plunger rod tip position at the end of the discharge to the valve block 34 functions as a buffer. Therefore, it is preferable to exclude the liquid as the buffer particularly when discharging at high speed tact.
[0044]
The storage container 1 can be appropriately replenished with liquid. Moreover, it is also possible to replace | exchange for another storage container 1 in which the liquid was stored.
The air cylinder A36 and the air cylinder B37 are connected to the air control means 10, and can supply air as required. The air control means 10, the motor A 20, and the motor B 38 are connected to the control unit 11 and operate based on a signal from the control unit 11.
[0045]
The discharge work is
(1) Adjust the tip of plunger rod A27 and plunger rod B28 to a position where they are equidistant from the cylinder block. This position is the base position.
(2) The plunger rod A27 is moved forward by driving the motor A1 by a volume amount that is half the desired discharge amount. At this time, the rotation of the motor A1 is transmitted to the gear B22 via the gear A21 so that the plunger rod B28 moves backward by half the volume of the desired discharge amount.
(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 moves the tip position of the plunger rod A27 closer to the valve block 34. B38 is driven, and the relative distance between the base block 49 and the sub-block 50 is adjusted so that the liquid remaining amount in the plunger chamber A31a is minimized, and preferably zero.
By driving the motor B, the plunger rod A27 and the plunger rod B28 move in translation integrally, so the relative distance between the plunger rod A27 and the plunger rod B28 does not change.
[0046]
(4) Here, the storage container 1 And the plunger chamber A31a are communicated, that is, the position of the valve block 34 is adjusted so that the nozzle 2 and the plunger chamber B31b communicate.
(5) Next, the plunger rod B28 is moved forward by driving the motor A20 by a desired discharge volume. At this time, the rotation of the motor A20 causes the plunger rod A27 to move backward by the desired discharge volume, so that the liquid in the storage container 1 is sucked into the plunger chamber A31a.
(6) Further, the position of the valve block 34 is adjusted so that the storage container 1 and the plunger chamber B31b communicate with each other, that is, the nozzle 2 and the plunger chamber A31a communicate with each other.
(7) The plunger rod A27 is moved forward by driving the motor A20 by a desired discharge volume. Since the plunger chamber A31a is filled with a desired amount of liquid, the liquid is discharged from the discharge port at the tip of the nozzle 2 by driving the motor A20. Further, the storage container 1 and the plunger chamber B31b are in communication with each other, and at this time, the plunger rod B28 moves backward by a desired discharge volume 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 discharged by the following operations 4 to 7.
[0047]
In this way, discharge is performed by the advancement of one plunger rod, and at the same time, the other plunger rod sucks the liquid into the plunger chamber, so that the discharge operation can be performed with high-speed tact.
[0048]
Example 2
In the first embodiment, the two plunger rods are driven by a single motor. However, in this embodiment, the motors 60 and 61 are connected to the two plunger rods 27 and 28, respectively. This is an example in which air pressure is applied to the liquid in the storage container 1 so that the plunger chambers A31a and B31b can be quickly filled with the liquid, and the main features are as follows.
[0049]
(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 moved independently. As a result, the discharge and suction speeds can be changed, so that it is possible to reduce the filling speed without changing the discharge speed in a liquid that takes a long time for suction, and suction that is inappropriate for the liquid. It is possible to suppress the occurrence of cavitation without applying force.
[0050]
(2) By rotating the two independent motors 60 and 61 in the same direction, the plunger rod A27 and the plunger rod B28 and the valve block 34 are kept constant while keeping the relative distance between the plunger rod A27 and the plunger rod B28 constant. In the second embodiment, it is not necessary to divide the base block and the sub-block as shown in FIG. 3 and slide them with a motor.
[0051]
(3) Since the air in the storage container 1 can be pressurized by the air control means 10 so that the liquid can be quickly sucked into the plunger chambers A31a and B31b from the storage container 1, the liquid supply to the plunger chamber can be performed at a high speed. Therefore, the discharge operation can be performed with a faster tact time. Great effect when discharging 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 out of the reach of the operator. . Similarly, the valve block and the nozzle can be communicated with each other via a liquid feeding tube.
[0052]
Example 3
In the first and second embodiments, a slide-type switching valve is used as the switching valve. However, in this embodiment, a rotary switching valve having a smooth sliding surface is used as the switching valve, and the surface in contact with the cylinder block is circular. A hole communicating with the pump portion provided on the surface of the cylinder block which is in close contact with the valve block of the cylinder block by rotating the disc-shaped valve body forming the arc-shaped flow path in one direction or repeatedly rotating, and the above-mentioned close contact surface The pump unit and the liquid storage container communicate with each other by an arc-shaped flow path provided in the disc-shaped valve body with a hole communicating with the liquid storage container provided in the plate and a hole communicating with the nozzle provided on the contact surface. The flow path is switched in the same manner as in the first or second embodiment by performing a switching operation between the state in which the pump unit and the nozzle communicate with each other.
[0053]
In any of the above-described embodiments, the one having two pump parts has been described. However, in the present invention, the pump part is used as one, the liquid flow path is connected to the plunger chamber and the liquid storage container, or the plunger It is also possible to switch the chamber and the nozzle so as to communicate with each other.
In addition, the plunger chamber is directly drilled in the cylinder block, but a separate cylinder can be fitted into the mounting hole drilled in the cylinder block to form the plunger chamber. In addition, the cylinder block is processed. It is also possible to use a material that is easy to do, fit a separate cylinder into the mounting hole bored in the cylinder block to form a plunger chamber, and form a sliding surface that is in close contact with the valve portion with a hard member.
Even if the plunger chamber is formed directly on the cylinder block, the surface of the cylinder block that contacts the valve portion is highly worn, and the sliding surface that is in close contact with the valve portion may be formed of a hard member.
[0054]
【The invention's effect】
In this way, the pump unit and the valve unit are connected and arranged, and the most advanced position of the plunger is the surface where the front end surface of the plunger is joined to the valve unit and the pump unit, thereby compressing an excess amount of liquid. In other words, it is possible to pressurize the minimum necessary liquid, that is, the liquid can be controlled with high responsiveness, and can be discharged at a high tact time.
Further, since the plunger tip position is always constant for each discharge, it is possible to discharge with high accuracy.
[Brief description of the drawings]
1 is a schematic diagram of Example 1. FIG.
FIG. 2 is an enlarged view of a main part of the first embodiment.
3 is a schematic diagram of Example 2. FIG.
[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 Sealing part
31 Cylinder block
31a Plunger chamber A
31b Plunger chamber B
32 Storage container attachment 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 feed 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 A 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

Claims (13)

A plunger section formed in a cylinder block and a plunger that reciprocates in the plunger chamber; a pump section that measures a desired amount of liquid to be discharged; and a valve section that has a valve block and switches between a suction and discharge liquid flow path; capable pump portion communicates with the position of the valve portion, and a reservoir for storing the liquid, and a discharge portion provided with a discharge port for discharging liquid, in a configuration Ru provided with,
The valve portion is configured to switch the suction and discharge liquid flow paths by sliding the valve block on the surface of the cylinder block having the opening of the plunger chamber, and the plunger block at the time of completion of discharge. An advancing position is a position where a plunger front end surface reaches a sliding surface between the cylinder block and the valve block .  2. The liquid dispensing apparatus according to claim 1, wherein the valve portion is detachably disposed on the pump portion. Plunger chamber, dispensing system for a liquid according to claim 1 or 2 is constituted by a cylindrical member mounted in a hole formed in the cylinder block.  4. The liquid dispensing apparatus according to claim 1, wherein the 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. .  The liquid dispensing apparatus according to any one of claims 1 to 4, wherein the switching valve is a slide-type switching valve.  The liquid dispensing apparatus according to claim 1, wherein the switching valve is a rotary switching valve having a smooth sliding surface. The liquid dispensing apparatus according to claim 5, further comprising a slide valve that applies air pressure to closely contact the cylinder block.  The liquid dispensing apparatus according to claim 1, further comprising a pressurizing unit that pressurizes the liquid in the storage container.  The liquid dispensing apparatus according to claim 1, wherein a plurality of pump units are provided, and a plurality of plungers constituting the pump units are driven by a single drive source.  The liquid dispensing apparatus according to claim 1, wherein a plurality of pump units are provided, and a plurality of plungers constituting the pump units are driven by independent drive sources. The liquid quantitative discharge device according to claim 9 or 10, wherein a suction operation of another plunger is performed during the discharge operation of any one of the plungers. The liquid dispensing apparatus according to any one of claims 1 to 11, wherein one line is formed by a single suction operation and a single discharge operation of the plunger. The liquid dispensing apparatus according to claim 1, wherein the pump unit measures a liquid to be discharged to a desired amount by controlling a last retracted position of the plunger.

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