JP5263262B2 - Metering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a quantitative discharge device which can improve the accuracy of the discharge amount of a liquid material. <P>SOLUTION: The quantitative discharge device 10 is structured so that, in a pair of opening/closing valves 40, 50, flow channel portions 41b, 51b of cavities 41, 51 and extension portions 41c, 51c thereof have the same cross-sectional area and support shafts 42b, 52b of valve bodies 42, 52 and extension shafts 42c, 52c thereof have the same cross-sectional area. Therefore, in a discharge preparation step, even when the valve bodies 42, 52 move in the cavities 41, 51 for opening/closing the valves 40, 50, the internal volume of the valves 40, 50 does not change, so that the liquid material inside the valves 40, 50 does not move. Consequently, in a discharge step, when an extrusion pin 62 extrudes the liquid material in a connecting pipe 25, the liquid material can be discharged quantitatively by the moved volume of the extrusion pin 62 with high accuracy. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a fixed amount discharge device that discharges a fixed amount of liquid material.

  2. Description of the Related Art Conventionally, as a fixed amount discharge device for discharging a liquid material in a fixed amount, for example, a fixed amount discharge device as disclosed in Patent Document 1 below is known. The fixed amount discharge device shown in FIG. 2 of Patent Document 1 supplies a fixed amount of liquid material from a nozzle provided at the tip of the syringe by supplying pressurized air to the liquid material stored in the syringe.

JP 2001-79472 A JP 2005-349363 A JP 2006-35149 A

  However, the following problems are present in the above-described conventional fixed-quantity dispensing apparatus. That is, it is very difficult to achieve a minute discharge of about 1 mg with high accuracy (for example, an error of ± 0.01 mg) by adjusting the discharge amount with pressurized air.

  Therefore, in order to realize such a small amount of discharge, a method of filling a liquid material in a flow path sandwiched between a pair of valves and pushing out the liquid material filled there by a pin is conceivable. At this time, it is considered that the amount of liquid material pushed out by the pin is controlled with high accuracy by controlling the movement amount of the pin with high accuracy.

  However, in such a technique, if the internal volume of the valve to be used fluctuates, it becomes difficult to push out the pin with high precision of the liquid material. Therefore, a valve in which the fluctuation of the internal volume is suppressed is necessary. It becomes.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a quantitative discharge device that improves the accuracy of the discharge amount of the liquid material.

  A fixed amount discharge device according to the present invention is a fixed amount discharge device that discharges a fixed amount of liquid material from a discharge nozzle, and is disposed in a flow path for flowing the liquid material from a syringe for storing the liquid material to the discharge nozzle, respectively. A pair of on-off valves and a push pin disposed in a flow path between the pair of on-off valves and moving forward and backward with respect to the flow path. The open / close valve has a cylindrical cavity and a direction in which the cavity extends. A shaft-like valve body that advances and retreats along the cavity, and the cavity constitutes a part of the flow path of the liquid material, and the flow path portion through which the liquid material flows and the flow path of the liquid material From the cross-sectional area of the flow path part and the extension part, which is arranged linearly with respect to the flow path part and is interposed between the extension part having the same cross-sectional area as the flow path part and the flow path part and the extension part. An enlarged portion having a large cross-sectional area, and the valve body is a flow path of the cavity And an extension shaft having the same cross-sectional area as the support shaft and an enlarged portion of the cavity, and when the valve body advances and retreats, And a diameter-enlarging part that closes the flow path part or the extension part.

  In this quantitative discharge device, a pair of on-off valves are arranged in a flow path for flowing the liquid material from the syringe to the discharge nozzle. In this on-off valve, the flow path portion and the extension portion of the cavity have the same cross-sectional area, and the support shaft and the extension shaft of the valve body have the same cross-sectional area. For this reason, even when the valve element advances and retreats in the cavity for opening and closing the on-off valve, the internal volume of the on-off valve does not change and the liquid material inside the on-off valve does not move. Therefore, when the push-out pin arranged in the flow path between the pair of on-off valves pushes out the liquid material in the flow path, the push-out amount of the liquid material can be adjusted with high accuracy. The discharge amount of the liquid material can be adjusted with high accuracy from the apparatus.

  In addition, a branch channel that branches upward from the channel between the pair of on-off valves and accommodates the push pin is further provided, and the branch channel has a branch flow and an outer peripheral surface of the push pin inside the channel side. The seal part which prevents inflow of the fluid material from the clearance gap with the internal peripheral surface of a path | route may be provided, and the aspect which has the recessed part for defoaming in a part of the outer peripheral surface may be sufficient as an extrusion pin. In this case, the liquid material mixed with bubbles can be guided to a branch channel that branches upward from the channel, and defoamed through the depression of the push pin.

  ADVANTAGE OF THE INVENTION According to this invention, the fixed quantity discharge apparatus by which the precision improvement of the discharge amount of the liquid material was achieved is provided.

FIG. 1 is a schematic configuration diagram of a quantitative discharge device according to an embodiment of the present invention. FIG. 2 is a diagram showing a procedure for discharging a liquid material using the fixed amount discharge apparatus of FIG. FIG. 3 is a diagram showing a procedure for performing defoaming of the liquid material by using the quantitative discharge device of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected about the same or equivalent element, and the description is abbreviate | omitted when description overlaps.

  As shown in FIG. 1, a fixed amount discharge device 10 according to an embodiment of the present invention is a fixed amount discharge device that discharges liquid material stored in a syringe 20 from a discharge nozzle 30 with a small discharge amount of about 1 mg. is there. The syringe 20 is a container for storing the liquid material to be discharged, and pumps the liquid material to the flow path at a predetermined pressure. A pair of on-off valves 40 and 50 are respectively arranged in the flow path from the syringe 20 to the discharge nozzle 30, and the on-off valves 40 and 50 are communicated with each other through a connecting pipe 25. Hereinafter, for convenience of explanation, of the pair of on-off valves 40, 50, the one on the upstream side of the flow path is referred to as the first on-off valve 40, and the one on the downstream side of the flow path is referred to as the second on-off valve 50. Called.

  The first on-off valve 40 includes a cylindrical cavity 41 and a shaft-like valve body 42 that advances and retreats in the cavity 41 along the extending direction thereof.

  The cavity 41 includes an enlarged portion 41a into which the liquid material in the syringe 20 flows in via the syringe pipe 21, and a flow path portion 41b and an extended portion 41c that are linearly arranged so as to sandwich the enlarged portion 41a. .

  The enlarged portion 41a is a portion having a hexagonal cross section, and the inner diameter of the central portion is larger than the inner diameter of the end portion on the flow path portion 41b side and the end portion on the extension portion 41c side.

  The flow path portion 41b and the extension portion 41c are cylindrical portions having the same cross-sectional shape and the same cross-sectional area, and extend along the direction of the axis of the valve body 42 described later. Here, the same cross-sectional shape and the same cross-sectional area are intended for a cross-section orthogonal to the axis of the valve body 42. Since the flow path part 41b is connected to the connecting pipe 25 and constitutes a part of the flow path of the liquid material, the liquid material can flow inside the flow path part 41b. On the other hand, the extension 41c is removed from the flow path of the liquid material, and the liquid material cannot flow through the extension 41c.

  The gap between the inner peripheral surface of the flow path portion 41b and the extension portion 41c and the outer peripheral surface of the valve body 42 is sealed by a seal portion S provided inside each. The seal part S of the flow path part 41b is provided on the side opposite to the enlarged part 41a side with respect to the position where the connecting pipe 25 is attached. Therefore, although the seal part S of the flow path part 41b prevents the liquid material from flowing out to the outside, the flow of the liquid material from the enlarged part 41a to the connecting pipe 25 is not hindered. The seal portion S of the extension portion 41c is provided at a position close to the enlarged portion 41a, and the liquid material in the enlarged portion 41a hardly flows into the extension portion 41c.

  The valve body 42 includes an enlarged diameter portion 42a accommodated in the enlarged portion 41a of the cavity 41, and a support shaft 42b and an extended shaft 42c that are linearly arranged so as to sandwich the enlarged diameter portion 42a.

  The enlarged diameter portion 42a is a spherical portion, and its diameter is larger than the diameters of the support shaft 42b and the extension shaft 42c, and is larger than the diameters of the flow path portion 41b and the extension portion 41c for accommodating them.

  The support shaft 42b and the extension shaft 42c are round bar-shaped portions having the same cross-sectional shape and the same cross-sectional area, and are arranged so as to extend along the same straight line (the axis of the valve body 42). It is attached to the enlarged diameter part 42a so that the enlarged diameter part 42a may be pinched | interposed from the side to do. Here, the same cross-sectional shape and the same cross-sectional area are intended for a cross-section orthogonal to the axis of the valve body 42.

  The support shaft 42 b is accommodated in the flow path portion 41 b, and one end portion thereof is connected to the enlarged diameter portion 42 a and the other end portion is connected to the driving means 43. The extension shaft 42c is accommodated in the extension portion 41c, and one end portion thereof is connected to the enlarged diameter portion 42a, and the other end portion is a free end. The driving means 43 to which the support shaft 42b is connected is for generating a driving force in the axial direction (extending direction) of the valve body 42 to advance and retract the valve body 42 along the extending direction. A pneumatic cylinder or a hydraulic cylinder can be employed.

  Since the first opening / closing valve 40 has the above-described configuration, the opening / closing operation of the valve can be performed by operating the driving unit 43.

  That is, when opening the first on-off valve 40, the valve body 42 is advanced to the side away from the driving means 43, and the enlarged diameter portion 42a in the enlarged portion 41a is connected to the communication port between the enlarged portion 41a and the flow path portion 41b. Move away from. As a result, the flow path from the enlarged portion 41a to the flow path portion 41b is opened, the liquid material that has flowed from the syringe 20 into the enlarged portion 41a flows into the flow path portion 41b, and the connecting pipe provided in the flow path portion 41b. The liquid material flows out from 25.

  On the other hand, when the first on-off valve 40 is closed, the valve body 42 is retracted toward the side closer to the driving means 43, and the communication port between the enlarged portion 41a and the flow passage portion 41b is formed by the enlarged diameter portion 42a in the enlarged portion 41a. Block. Thereby, the flow path from the enlarged part 41a to the flow path part 41b is closed, and the liquid material that has flowed into the enlarged part 41a from the syringe 20 does not flow into the flow path part 41b, and the liquid material remains in the enlarged part 41a.

  In the first on-off valve 40, as described above, the flow path portion 41b and the extension portion 41c have the same cross-sectional area, and the support shaft 42b and the extension shaft 42c have the same cross-sectional area. No change in volume occurs during the opening / closing operation. Therefore, the liquid material inside the first on-off valve 40 does not move when the first on-off valve 40 is opened or closed, and therefore the liquid material does not flow out to the connecting pipe 25, and the connecting pipe 25 No inflow from. Therefore, the liquid material inside the connecting pipe 25 does not substantially move during the opening / closing operation of the first opening / closing valve 40.

  A valve seat 44 is provided around the communication port between the enlarged portion 41a and the flow channel portion 41b. The valve seat 44 increases the rigidity of the communication port, or between the communication port and the enlarged diameter portion 42a. It may be possible to improve the sealing performance.

  The second on-off valve 50 has the same configuration as the first on-off valve 40 described above. That is, the second on-off valve 50 includes a cavity 51 similar to the cavity 41 of the first on-off valve 40 and a valve body 52 similar to the valve body 42 of the first on-off valve 40.

  Therefore, like the first on-off valve 40, the second on-off valve 50 can perform the opening / closing operation of the valve by operating the driving means 53.

  That is, when opening the second on-off valve 50, the valve body 52 is advanced to the side away from the driving means 53, and the enlarged diameter part 52a in the enlarged part 51a is connected to the communication port between the enlarged part 51a and the flow path part 51b. Move away from. Thereby, the flow path from the flow path portion 51b to the enlarged portion 51a is opened, and the liquid material that has flowed into the flow path portion 51b to which the connecting pipe 25 is attached flows into the enlarged portion 51a, and is further provided in the enlarged portion 51a. The liquid material is discharged from the discharge nozzle 30.

  On the other hand, when the second on-off valve 50 is closed, the valve body 52 is retracted toward the side closer to the drive means 53, and the communication port between the enlarged portion 51a and the flow path portion 51b is formed by the enlarged diameter portion 52a in the enlarged portion 51a. Block. Thereby, the flow path from the flow path portion 51b to the enlarged portion 51a is closed, and the liquid material that has flowed into the flow path portion 51b from the connecting pipe 25 does not flow into the enlarged portion 51a, and the liquid material is in the flow path portion 51b. stay.

  Also in the second on-off valve 50, with respect to a cross section orthogonal to the axis of the valve body 52, the flow path portion 51b and the extension portion 51c have the same cross-sectional area, and the support shaft 52b and the extension shaft 52c have the same cross-sectional area. Therefore, the volume does not change during the valve opening / closing operation described above. Therefore, as with the opening / closing operation of the first opening / closing valve 40, the liquid material inside the second opening / closing valve 50 does not move during the opening / closing operation of the second opening / closing valve 50. The liquid material inside the nozzle 30 also does not move substantially.

  A liquid extruding section 60 is provided in the flow path between the first on-off valve 40 and the second on-off valve 50, that is, in the middle of the connecting pipe 25.

  The liquid extruding unit 60 includes a branch pipe 61 that branches upward so as to be orthogonal to the connection pipe 25, an extrusion pin 62 that is accommodated in the branch pipe 61, and a drive unit 63 that drives the extrusion pin 62. ing.

  One end of the branch pipe 61 is in communication with the connecting pipe 25, and forms a branch flow path that branches off from the liquid material flow path described above. At both ends of the branch pipe, a gap between the inner peripheral surface and the outer peripheral surface of the push pin 62 is sealed by a seal portion S provided inside the branch pipe. Therefore, the liquid material in the connection pipe 25 hardly flows into the branch pipe 61 due to the seal portion S at the end on the connection pipe 25 side, and the liquid material in the branch pipe 61 is discharged to the outside by the seal part on the opposite side. Outflow is prevented.

  Further, a defoaming pipe 70 is connected to the branch pipe 61 at a position sandwiched between the seal portions S at both ends. One end portion of the defoaming tube 70 is connected to the branch tube 61, and the other end portion extends upward.

  The push pin 62 extends along the extending direction of the branch pipe 61. One end of the push pin 62 is connected to the driving means 63, and the other end is a free end. The drive means 63 to which the push pin 62 is connected is for generating a driving force in the extending direction of the push pin 62 and moving the push pin 62 back and forth along the extending direction. For example, a servo motor or a stepping motor is used. A linear actuator that combines a driven ball screw and a linear guide can be employed. Further, the push-out pin 62 is formed with a defoaming recess 62a on a part of the outer peripheral surface thereof.

  Since the liquid extruding part 60 is configured as described above, the liquid material in the connecting pipe 25 can be pushed out by operating the driving means 63. That is, when the liquid material is introduced into the connecting pipe 25, the push pin 62 is retracted in advance toward the driving means 63, and after the liquid material is introduced into the connecting pipe 25, the push pin is moved away from the driving means 63. By advancing 62, the liquid material in the connecting pipe 25 is pushed out.

  In addition, in the liquid extruding part 60, the liquid material guided to the branch pipe 61 can be defoamed by the recess 62 a of the push pin 62. That is, the branch pipe 61 and the defoaming pipe 70 are locally opened through the concave portion 62a by matching the position of the concave portion 62a of the push pin 62 with the position of the seal portion S at the end on the connecting pipe 25 side. Thereby, the liquid material mixed with bubbles is selectively flowed from the branch pipe 61 to the defoaming pipe 70 to defoam the liquid material.

  Next, with reference to FIG. 2, a procedure for discharging the liquid material using the above-described quantitative discharge device 10 will be described.

  FIG. 2A shows a material filling stage of the liquid material of the fixed quantity discharge device 10. At this stage, the first on-off valve 40 has the valve body 42 in the advanced position and the valve is open, and the second on-off valve 50 has the valve body 52 in the retreat position and the valve is closed. Therefore, the liquid material stored in the syringe 20 flows into the connecting pipe 25 through the first on-off valve 40, and the inside of the first on-off valve 40 and the connecting pipe 25 is filled with the liquid material. In the material filling stage, the push pin 62 of the liquid pusher 60 is in the retracted position.

  At this stage, the flow path from the syringe 20 to the discharge nozzle 30 is filled with the liquid material over the entire area. Filling the flow paths other than the first on-off valve 40 and the connecting pipe 25 (that is, the second on-off valve 50 and the discharge nozzle 30) is performed at the time of trial driving before the material filling stage.

  FIG. 2B shows a liquid material discharge preparation stage of the quantitative discharge device 10. In the discharge preparation stage following the material filling stage, the valve body 42 of the first on-off valve 40 is retracted to close the first on-off valve 40, and the valve body 52 of the second on-off valve 50 is advanced to advance. 2 on-off valve 50 is opened. As described above, during the opening / closing operation of the first on-off valve 40 and the second on-off valve 50, the liquid material inside the connecting pipe 25 and the discharge nozzle 30 does not substantially move. Even in the discharge preparation stage, the push pin 62 of the liquid pusher 60 is still in the retracted position.

  FIG. 2 (c) shows the liquid material discharge stage of the quantitative discharge device 10. In the discharge stage following the discharge preparation stage, the push-out pin 62 of the liquid extruding unit 60 advances and presses the liquid material inside the connecting pipe 25. As a result, the liquid material inside the connecting pipe 25 flows toward the open second on-off valve 50 and is discharged from the discharge nozzle 30 via the second on-off valve 50. That is, the liquid material is discharged from the discharge nozzle 30 by the amount of volume movement of the push pin 62 (that is, only the volume of the liquid material displaced by the push pin 62). Therefore, a fixed amount of liquid material is repeatedly discharged by keeping the amount of forward and backward movement of the push-out pin 62 constant by the driving means 63 of the liquid extruding unit 60.

  As described above, in the on-off valves 40 and 50 of the fixed-quantity discharge device 10, the flow passage portions 41b and 51b and the extension portions 41c and 51c of the cavities 41 and 51 have the same cross-sectional area, and the valve element 42 , 52 support shafts 42b and 52b and extension shafts 42c and 52c have the same cross-sectional area. Therefore, even when the valve bodies 42 and 52 advance and retreat in the cavities 41 and 51 in order to open and close the on-off valves 40 and 50 in the discharge preparation stage shown in FIG. The internal volume does not change, and the liquid material inside the on-off valves 40 and 50 does not move.

  Therefore, in the discharge stage shown in FIG. 2C, the push pin 62 arranged so as to intersect the connecting pipe 25 that is a flow path between the pair of on-off valves 40 and 50 is a liquid material of the connecting pipe 25. When the is pushed out, a fixed amount of liquid material can be discharged with high accuracy (for example, a discharge amount of about 1 mg with an error of ± 0.01 mg) by the amount of volume movement of the push pin 62. That is, in the fixed quantity discharge device 10, the amount of liquid material extruded can be adjusted with high accuracy, and as a result, the amount of liquid material discharged can be adjusted with high accuracy.

  In the above-described material filling stage, the flow path from the syringe 20 to the discharge nozzle 30 needs to be filled with the liquid material over the entire area, and no bubbles are mixed in the liquid material. Is preferred.

  Therefore, it is preferable to perform a defoaming treatment as described below prior to the material filling stage. FIG. 3 is a diagram showing a procedure for defoaming the liquid material.

  In the defoaming process, first, as shown in FIG. 3A, the first on-off valve 40 advances the valve body 42 to open the valve, and the second on-off valve 50 has the valve body 52. Regress and keep the valve closed. Then, the liquid material is introduced from the syringe 20 into the connecting tube 25.

  Subsequently, as shown in FIG. 3B, the push-out pin 62 is moved by the driving means 63 of the liquid extruding unit 60 while the first on-off valve 40 is opened and the second on-off valve 50 is closed. Make it progress. At this time, the position of the concave portion 62a of the push pin 62 is matched with the position of the seal portion S at the end on the connecting pipe 25 side. Then, the branch pipe 61 and the defoaming pipe 70 are locally opened through the recess 62a. Thereby, the liquid material mixed with bubbles selectively flows from the branch pipe 61 to the defoaming pipe 70, and the liquid material is defoamed.

  In addition, since the specific gravity of the foam is lower than that of the liquid material and the foam is likely to be present on the upper side of the liquid material, the foam is mixed by branching the branch pipe 61 of the liquid extruding unit 60 from the connecting pipe 25 to the upper side. The liquid material is effectively introduced into the branch pipe 61.

  DESCRIPTION OF SYMBOLS 10 ... Fixed-quantity discharge apparatus, 20 ... Syringe, 30 ... Discharge nozzle, 40, 50 ... On-off valve, 41, 51 ... Cavity, 41a, 51a ... Expansion part, 41b, 51b ... Channel part, 41c, 51c ... Extension part, 42, 52 ... Valve body, 42a, 52a ... Diameter expansion part, 42b, 52b ... Support shaft, 42c, 52c ... Extension shaft, 60 ... Liquid extrusion part, 62 ... Extrusion pin, S ... Seal part.

Claims (2)

A fixed amount discharge device for discharging a fixed amount of liquid material from a discharge nozzle,
A flow path for flowing the liquid material from a syringe storing the liquid material to the discharge nozzle;
A pair of on-off valves respectively disposed in the flow path;
An extrusion pin disposed in the flow path between the pair of on-off valves and moving forward and backward with respect to the flow path;
The on-off valve has a cylindrical cavity and a shaft-like valve body that advances and retreats in the cavity along its extending direction,
The cavity is
Constituting a part of the flow path of the liquid material, and a flow path section through which the liquid material flows;
An extension portion that is linearly arranged with respect to the flow path portion so as to be separated from the flow path of the liquid material, and has the same cross-sectional area as the flow path portion;
Including an enlarged portion interposed between the flow path portion and the extension portion, and having a cross-sectional area larger than the cross-sectional area of the flow path portion and the extension portion,
The valve body is
A support shaft housed in the flow path portion of the cavity;
An extension shaft housed in the extension of the cavity and having the same cross-sectional area as the support shaft;
A fixed-quantity discharge device including an enlarged-diameter portion that is accommodated in the enlarged portion of the cavity and closes the flow passage portion or the extension portion of the cavity when the valve body advances and retreats. Branching upward from the flow path between the pair of on-off valves, and further comprising a branch flow path for accommodating the push pin,
The branch channel has a seal portion for preventing the fluid material from flowing in from the gap between the outer peripheral surface of the push pin and the inner peripheral surface of the branch channel inside the channel.
The quantitative discharge device according to claim 1, wherein the extrusion pin has a defoaming recess in a part of an outer peripheral surface thereof.

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