JP2019074000A - Syringe pump - Google Patents

Abstract

To prevent piston slide resistance from increasing due to residues adhering to an inner peripheral surface of a cylinder or an outer peripheral surface of an annular seal material, in a syringe pump.SOLUTION: A syringe pump is provided with: cleaning and drying means 31 of supplying cleaning liquid L to an interval portion between a piston 4 and an inner peripheral surface of a cylinder 3 on an opposite side to a charging chamber 10 with respect to an annular seal material 13 mounted in the piston 4, to clean the interval portion, and supplying gas for dryness A to the cleaned interval portion, to dry the cleaned interval portion; and a seal liquid supply means 32 of supplying to the interval portion seal liquid S having lubricity, following cleaning and drying processing at the interval portion by the cleaning and drying means 31.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a syringe pump used to supply various liquids such as liquid paint and paint hardening liquid to a coating machine, and more specifically, to a piston slidably disposed inside a cylinder, the piston and the inner circumferential surface of the cylinder An annular seal member is provided for sealing the gap, and the liquid filled in the filling chamber between the bottom wall of the cylinder and the piston through the filling passage is discharged by the sliding of the piston toward the side of the bottom wall. The syringe pump discharges from the filling chamber through the

  Conventionally, in this type of syringe pump, after the liquid such as paint filled in the filling chamber is discharged from the filling chamber by sliding of the piston, the cleaning solution and the drying gas are sequentially supplied to the empty filling chamber. In this way, a cleaning and drying process is generally performed in which the filling chamber in the cylinder is cleaned and dried prior to the next liquid filling.

  Then, in Patent Document 1 below, when the filling chamber is cleaned, a cleaning gap having a large gap width is created between the inner circumferential surface of the cylinder and the piston, and the cleaning solution supplied to the filling chamber is made into the cleaning gap. There has been proposed a syringe pump in which the residue adhering to the inner circumferential surface of the cylinder, the outer circumferential surface of the annular seal material in the piston, and the like is washed away by a cleaning solution by passing the solution.

JP, 2014-224517, A

  However, the residue attached to the inner peripheral surface of the cylinder and the outer peripheral surface of the annular seal material in the piston (in particular, the residue in the form of a film formed by the curing component contained in the liquid paint and the paint curing liquid) It is difficult to completely remove it by itself, and therefore, in the conventional syringe pump, the sliding resistance of the piston becomes large due to the accumulation of this residue, and the sliding of the piston becomes defective and the pump function decreases. There has been a problem of causing an unexpected pump stop or causing premature wear of the annular seal material on the piston.

  Moreover, in order to prevent this, the maintenance work for disassembling each part of the pump and removing attached residue must be frequently performed, which increases the maintenance burden and reduces the operation efficiency of the pump. There was a problem.

  In view of this situation, the main object of the present invention is to effectively solve the above problems by rational improvement.

The first feature configuration of the present invention relates to a syringe pump, and the feature is that
The piston slidably disposed inside the cylinder is equipped with an annular seal member for sealing between the piston and the inner circumferential surface of the cylinder,
A syringe which discharges the liquid filled in the filling chamber between the one bottom wall of the cylinder and the piston through the filling passage from the filling chamber through the discharge passage by the sliding of the piston toward the one side bottom wall A pump,
A cleaning solution is supplied to a gap between the piston and the inner peripheral surface of the cylinder on the side opposite to the filling chamber with respect to the annular seal member to clean the gap, and the gap after cleaning There is provided a washing / drying means for supplying a drying gas to the part to dry the gap after washing, and
Subsequent to the cleaning and drying process of the gap portion by the cleaning and drying means, a seal liquid supply means for supplying a sealing liquid having lubricity to the gap portion is provided.

  According to this configuration (see FIGS. 9 and 10), the gap portion 29 between the piston 4 and the cylinder inner peripheral surface 3a on the side opposite to the filling chamber 10 with respect to the annular seal member 13 of the piston 4 is cleaned. After being subjected to washing and drying processing by the sequential supply of the washing liquid L and the drying gas A by the drying means 31, the seal liquid S having the lubricating property is supplied to the gap portion 29 by the seal liquid supply means 32. The adhesion residue (in particular, a film-like residue formed by a curing component contained in the liquid filled in the filling chamber 10) remains on the inner peripheral surface 3a of the cylinder and the outer peripheral surface of the annular sealing material 13 regardless of the drying process. Also, the seal function between the cylinder inner peripheral surface 3a and the piston 4 by the sealing function of the seal liquid S supplied to the gap portion 29 (strictly speaking, the outside of the cylinder inner peripheral surface 3a and the annular seal member 13 While maintaining high sealability) between the surfaces, an increase in the piston sliding resistance by adhering residues, it can be effectively prevented by the lubricating function of the supplied sealing liquid S.

  In addition, a liquid film of the sealing liquid S is formed on the inner peripheral surface 3a of the cylinder and the outer peripheral surface of the annular sealing material 13 with the sliding of the piston 4 after supplying the sealing liquid S to the gap portion 29. By the presence of the above, adhesion of the residue itself to the cylinder inner peripheral surface 3a and the outer peripheral surface of the annular seal member 13 can be suppressed, and from this point as well, increase in piston sliding resistance due to the adhesion residue can be prevented. .

  Therefore, according to the above configuration, it is possible to effectively prevent the pump function from being lowered due to an increase in the sliding resistance of the piston 4 due to the adhesion residue, unexpected pump stoppage or premature wear of the annular seal member 13 or the like. Can.

  Further, maintenance work for disassembling each part of the pump and removing attached residue is unnecessary, or the frequency of the necessity can be reduced, and the burden of maintenance can be reduced and the operation efficiency of the pump can be enhanced. it can.

A second feature of the present invention specifies an embodiment suitable for the implementation of the first feature, the feature being
A cleaning supply passage for guiding the cleaning solution and the drying gas to the gap portion; a cleaning discharge passage for discharging the cleaning solution and the drying gas supplied to the gap portion from the gap portion; An on-off valve is provided in each of the seal liquid supply path leading to the gap portion,
Control means for controlling the cleaning and drying means and the sealing liquid supply means is, as on-off valve control for opening and closing each on-off valve,
When the cleaning liquid and the drying gas are supplied to the gap portion, the on-off valve provided in the seal liquid supply passage is closed, and the cleaning supply passage and the cleaning discharge passage are provided. Open the on-off valve,
When the seal liquid is supplied to the gap portion, the on-off valve provided on each of the cleaning supply path and the cleaning discharge path is closed, and the on-off valve provided on the seal liquid supply path is opened. It is in the point which is made to the composition.

  According to this configuration, when the cleaning liquid L and the drying air A are supplied to the gap portion 29 (see FIG. 8), the on-off valve V1, which is interposed in each of the cleaning supply passage 33 and the cleaning discharge passage 37. Since V3 is opened, the cleaning liquid L and the drying gas A supplied to the gap portion 29 through the cleaning supply path 33 are supplied to the gap portion 29 through the cleaning discharge path 37. It is possible to supply the cleaning liquid L and the drying gas A temporarily to the gap portion 29 so as to discharge from the space, whereby the processing effect and processing of the cleaning and drying process on the gap portion 29 can be provided. It can increase the efficiency.

  In addition, when the sealing liquid S is supplied to the gap portion 29 (see FIG. 10), the on-off valves V1 and V3 interposed in the cleaning supply passage 33 and the cleaning discharge passage 37 are closed to make the clearance The seal liquid S can be effectively applied in a pressurized form to the seal portion between the cylinder inner peripheral surface 3a connected to the portion 29 and the outer peripheral surface of the annular seal member 13, whereby the adhesion residue An increase in piston sliding resistance can be more effectively prevented.

The third feature of the present invention specifies an embodiment suitable for the implementation of the first or second feature, the feature being
A seat member is provided to abut and stop the piston sliding to a side away from the one side bottom wall;
The piston and the seat member have a structure in which a relay chamber is formed between the piston and the seat member when the piston abuts on the seat member.
The piston is provided with a communication passage for connecting the relay chamber to the gap portion,
The cleaning and drying unit and the sealing liquid supply unit are configured to supply the cleaning liquid, the drying gas, and the sealing liquid to the gap through the relay chamber and the communication passage.

  According to this configuration (see FIGS. 8 and 10), when the piston 4 is in contact with the seat member 14, the cleaning liquid L and the drying gas A and the sealing liquid S are respectively passed through the relay chamber 28 and the communication passage 30. Can be supplied smoothly and accurately to the gap portion 29, thereby enhancing the processing effect and processing efficiency of the cleaning and drying process on the gap portion 29, and further increasing the piston sliding resistance due to the adhesion residue. It can be effectively prevented.

The fourth feature of the present invention specifies an embodiment suitable for implementing any of the first to third features, and the feature is
After the filling chamber is filled with the liquid through the filling passage, and the filling passage and the discharge passage are closed, the piston is pressed by a piston rod by a predetermined moving amount for pressurization by the side of the one bottom wall The air bubble is slidingly moved to detect the pressure change of the liquid in the filling chamber at that time, and based on the detected pressure change, it is determined whether the liquid in the filling chamber contains bubbles or not. It is in the point provided with the existence judging means.

  According to this configuration (see FIG. 5), it is possible to prevent the liquid discharge from becoming unstable due to the inclusion of air bubbles in the liquid T filled in the filling chamber 10.

  That is, when the liquid T filled in the filling chamber 10 contains air bubbles, a large amount of the liquid T is discharged from the filling chamber 10 at the beginning of the discharge step of discharging the liquid T from the filling chamber 10 At the end of the discharge process in which the piston 4 approaches the one-side bottom wall 7 of the cylinder 3, the filling chamber 10 already becomes empty without liquid even though the discharge process is not yet completed. Cause trouble.

  On the other hand, in the above configuration, after filling the filling chamber 10 with the liquid T, the piston 4 is pressed by the piston rod 5 in a state in which the filling passage 23 and the discharge passage 20 are closed to prevent fluid delivery from the filling chamber 10. Based on the change form of the pressure change on the rising side of the liquid T in the filling chamber 10 when it is slid to the one side bottom wall 7 side (that is, the pressure side) of the cylinder 3 by the predetermined pressure moving amount e. Then, the presence or absence of bubbles in the liquid T in the filling chamber 10 is determined by the bubble presence / absence determination means 38a.

  That is, when there is no air bubble in the liquid T filled in the filling chamber 10, the pressure of the liquid T in the filling chamber 10 rises promptly due to the incompressibility of the liquid T when pressure is applied by the piston sliding. When air bubbles are present in the liquid T filled in the chamber 10, the pressure of the liquid T in the filling chamber 10 rises only slowly due to the compressibility of the air bubbles regardless of the pressure due to the piston sliding.

  Using this fact, the presence / absence of bubbles in the liquid T in the filling chamber 10 is determined by the bubble presence / absence determination means 38a.

  Therefore, when the liquid T filled in the filling chamber 10 contains air bubbles, an alarm for prompting the pump to stop is issued prior to the start of liquid discharge from the filling chamber 10 according to the determination by the air bubble presence / absence determination means 38a. Appropriate measures such as stopping the pump or automatically stopping the pump can be taken, thereby destabilizing the liquid discharge caused by the inclusion of air bubbles in the liquid T filled in the filling chamber 10 Can be prevented.

The fifth feature of the present invention specifies an embodiment suitable for the implementation of the fourth feature, and the feature is that
The bubble presence / absence determination means is configured to return and slide the piston away from the one side bottom wall by the pressure of the liquid in the filling chamber after detecting a change in pressure of the liquid in the filling chamber. It is on the point.

  According to this configuration (see FIG. 5), the piston 4 is slid toward the one-side bottom wall 7 by the predetermined pressure moving amount e by the bubble presence / absence determination means 38a, and the bubbles in the liquid T in the filling chamber 10 are After determining the presence or absence, the pressure of the liquid T in the filling chamber 10 can be rapidly reduced to a pressure suitable for liquid supply to the supply destination without wasting the liquid T in the filling chamber 10 wastefully.

  That is, in the syringe pump of this type, when the piston 4 is made to slide away from the one side bottom wall 7 of the cylinder 3 in order to prevent the bubbles T from being contained in the liquid T filled in the filling chamber By sliding the piston 4 by the pressure of the liquid T filled in the chamber 10, the filling chamber 10 is maintained at a positive pressure. Thereafter, in order to reduce the pressure of the liquid T in the filling chamber 10 raised in the bubble presence / absence judgment by the bubble presence / absence judgment means 38a to a pressure suitable for liquid supply to the supply destination, the filling raised in the bubble presence / absence judgment The method of sliding the piston 4 away from the one side bottom wall 7 of the cylinder 3 by the pressure of the liquid T in the chamber 10, and the method of discharging a part of the liquid T in the filling chamber 10 from the filling chamber 10 Can be considered.

  However, in the former method of sliding the piston 4 by the pressure of the liquid T in the filling chamber 10 raised in the determination of the presence or absence of bubbles, the piston 4 is smooth due to the increase in the sliding resistance of the piston due to the adhesion residue as described above. There is a problem that it is difficult to properly reduce the pressure of the liquid T in the filling chamber 10, and the latter method of discharging a part of the liquid T in the filling chamber 10 There is a problem that the liquid T to be discharged is wasted.

  On the other hand, according to the fifth feature configuration subordinate to the first feature configuration described above, the increase in the sliding resistance of the piston can be effectively prevented by the supply of the seal liquid S by the seal liquid supply means 32 as described above. In the state where the sliding failure of the piston 4 is effectively prevented while adopting the former method of sliding the piston 4 by the pressure of the liquid T in the filling chamber 10 raised by the determination of the presence or absence of bubbles, The pressure of the liquid T in the filling chamber 10 can be reliably and smoothly reduced to a pressure suitable for liquid supply to the supply destination without wasting a part of the liquid T in 10 wastefully.

Longitudinal sectional view of syringe pump showing bubble removal process Enlarged vertical sectional view of cylinder and piston Enlarged view of one side bottom wall in cylinder Longitudinal sectional view of a syringe pump showing a filling process Longitudinal sectional view of a syringe pump showing a bubble presence / absence determination process Longitudinal sectional view of a syringe pump showing a discharge process Longitudinal cross-sectional view of a syringe pump showing a cleaning and drying process for a gap portion Enlarged cross-sectional view showing the cleaning and drying process for the gap portion Longitudinal cross-sectional view of syringe pump showing seal liquid supply to gap portion Enlarged sectional view showing seal liquid supply to the gap portion Longitudinal sectional view of a syringe pump showing the second half of the washing and drying process for the filling chamber Device configuration diagram showing another embodiment

  1 to 3 and 8 show a syringe pump 2 for supplying a liquid paint T to a coating machine 1, and the paint T supplied to the coating machine 1 from this syringe pump 2 is a car body or the like by the coating machine 1. It is sprayed on the substrate and used to paint the substrate.

  The syringe pump 2 includes a cylinder 3, a piston 4 slidably installed inside the cylinder 3, and a piston rod 5 for pressing the piston 4 from the back side.

  The cylinder 3 is attached to the one side bottom wall 7 attached to one end in the longitudinal direction via the annular connection member 6 and the other side bottom attached to the other end in the longitudinal direction via the annular connection member 8 It has a wall 9.

  Inside the cylinder 3, the filling chamber 10 is formed between the one side bottom wall 7 and the piston 4, and in the one side bottom wall 7 of the cylinder 3, the filling hole 11 opening to the filling chamber 10 and the discharge A hole 12 is formed.

  An annular seal 13 is mounted on the outer peripheral edge of the front face of the piston 4 to make the inner peripheral surface 3 a of the cylinder 3 slide in sliding movement of the piston 4. The space between the circumferential surface 3 a and the piston 4 is sealed.

  On the other hand, a seat member 14 is internally provided in the cylinder 3 on the side of the other side bottom wall 9 in contact with the other side bottom wall 9, and the piston rod 5 has the other side bottom wall 9 and Rod through holes 15 and 16 formed in the seat member 14 are penetrated.

  In addition, the piston rod 5 is caused to move forward and backward by rotating the screw rod 17 engaged with the inner screw portion 5 a by the servomotor 18 via the transmission device 19.

  The discharge hole 12 in the one-side bottom wall 7 is connected to the paint inlet of the coating machine 1 through a discharge passage 20, and a paint supply valve Va for the coating machine 1 is interposed in the discharge passage 20.

  The recovery passage 21 is branched from the discharge passage 20 at a position upstream of the paint supply valve Va, and the recovery passage 21 is connected to the recovery container 22.

  The dump valve Vb and the saver valve Vc are interposed in the collection passage 21 in order from the upstream side at predetermined intervals.

  On the other hand, the switch 24 is connected to the filling hole 11 in the one side bottom wall 7 through the filling passage 23. This switching device 24 is a fluid supplied to the filling chamber 10 through the filling passage 23 and the filling hole 11. Is selectively switched to one of a plurality of types of paints T1 to Tn having different colors and the like, a cleaning liquid L such as thinner, and a drying gas A such as dry air.

Moreover, in the syringe pump 2 of this example, the following structure is provided as a characteristic structure other than the above basic structure.
That is, on the one side bottom wall 7 of the cylinder 3 is attached a projecting pin 25 which protrudes by a predetermined dimension (for example, about 0.3 mm) in the filling chamber 10 from the inner surface of the one side bottom wall 7. Even when the piston 4 is brought closest to the side of the one side bottom wall 7 with the pressure by the piston rod 5, the inner surface of the one side bottom wall 7 and the front face 4a of the piston 4 A bottom gap 26 is left between them.

  Further, the annular seal 13 is equipped on the piston 4 by retracting its front edge by a predetermined dimension (for example, about 1 mm) from the front surface 4 a of the piston 4, whereby the piston 4 is on the side of the one side bottom wall 7 A groove-shaped annular gap 27 is formed around the bottom gap 26 in the closest state to the bottom gap 26.

  Further, in the one side bottom wall 7 of the cylinder 3, each of the filling hole 11 and the discharge port 12 is formed in the one side bottom wall 7 so as to be opened to the formation position of the annular gap 27.

  On the other hand, in the piston 4 and the seat member 14 on the other side bottom wall 9 side, the relay chamber 28 is formed between the piston 4 and the seat member 14 in the state where the piston 4 abuts on the seat member 14 In the piston 4, a relay chamber 28 is communicated with a gap portion 29 between the piston 4 and the cylinder inner peripheral surface 3 a on the side opposite to the filling chamber 10 with respect to the annular seal member 13. A passage 30 is formed.

  Further, a cleaning / drying unit 31 for a clearance portion is provided as a cleaning / drying means for selectively supplying a cleaning liquid L such as thinner and a drying gas A such as dry air to the clearance portion 29. A seal liquid supply device 32 for a gap portion is provided as a seal liquid supply means for supplying the seal liquid S having lubricity.

  The cleaning / drying unit 31 for the gap portion is provided around the piston rod 5 in the cleaning supply passage 33 having the on-off valve V1 and the other side bottom wall 9 and the rod through holes 15 and 16 of the seat member 14 respectively. The cleaning liquid L and the drying gas A are sent to the relay chamber 28 through the flow path portion 34, and similarly, the seal liquid supply device 32 for the gap portion includes the seal liquid supply path 35 with the on-off valve V2 interposed, The seal liquid S is sent to the relay chamber 28 through the flow passage portion 34 around the piston rod 5.

  The cleaning liquid L and the drying gas A supplied to the gap portion 29 are supplied to the on-off valve V3 through the flow path portion 36 around the other side bottom wall 9 and the seat member 14 in the central mounting hole 8a of the connecting member 8. It is discharged to the cleaning discharge passage 37 with the

  Reference numeral 38 denotes a pump controller, which measures load torque m of the servomotor 18 as information indicating the pressure of the fluid filled in the filling chamber 10, and measures it under a set painting schedule. The respective valves Va to Vc and V1 to V3 and the switch 24 and the servomotor 18 are automatically operated based on the load torque m.

  Specifically, the pump controller 38 executes the following steps (a) to (f) in this order for each paint supply to the coating machine 1 each time.

  (A) In filling the filling chamber 10 with the used paint T, first, as shown in FIGS. 1 and 2, the piston 4 is brought into contact with the projecting pin 25 of the one-side bottom wall 7 by pressing with the piston rod 5 With the paint supply valve Va and the saver valve Vc closed and the dump valve Vb opened while holding the state, the paint T to be used for that time from the switch 24 to the filling chamber 10 through the filling passage 23 for a set time. Carry out the bubble removal step to be supplied.

  That is, in this air bubble removal process, the paint T used for that time is made to pass temporarily in the order of filling path 23 → filling hole 11 → annular gap 27 and bottom gap 26 → discharge port 12 → discharge path 20 And the gas remaining in the filling passage 23 and the filling chamber 10 (ie, the drying gas A remaining in the filling passage 23 and the filling chamber 10 in the previous washing and drying process for the filling passage 23 and the filling chamber 10) .

  The gas A removed from the filling passage 23 and the filling chamber 10 together with the paint T is accumulated in a mixed state with the paint T in a portion between the dump valve Vb and the saver valve Vc in the recovery passage 21 through the dump valve Vb.

  That is, in the state where the dump valve Vb is opened and the saver valve Vc is closed as described above, the recovery passage 21 is removed by removing the residual gas A in the filling passage 23 and the filling chamber 10 by extrusion with the paint T. Compared to exhausting the residual gas A in the filling passage 23 and the filling chamber 10 by extruding with the coating material T in an all-over manner, the amount of the coating material T spent for eliminating the residual gas A is effectively reduced. Can.

  (B) Subsequent to the bubble removing step, as shown in FIG. 4 as the filling step, with the paint supply valve Va and the dump valve Vb closed, the piston rod 5 is independent of the piston 4 on the one side bottom wall 7 Move backward to the side away from the head to retract the tip of the piston rod 5 to a position corresponding to the required supply amount of the paint T at that time, and with this, the paint T used for that time continues to the previous bubble removal step. By supplying from the switch 24 to the filling chamber 10 through the filling passage 23, the piston 4 is slid away from the one-side bottom wall 7 by the supply pressure of the paint T.

  Then, the pressure of the paint T in the filling chamber 10 is transmitted to the piston rod 5 via the piston 4 in contact with the piston rod 5, and the load torque m of the servomotor 18 being measured rises. When it is detected that the filling chamber 10 is filled with the paint T, the paint supply from the switch 24 is stopped to complete the filling process.

  That is, at the end of this filling process, the used paint T of that time is measured by the amount necessary for the paint supply to the coating machine 1 of that time, and the filling chamber 10 is filled.

  Also, in order to fill the filling chamber 10 with the paint T, the piston 4 is made to slide away from the one-side bottom wall 7 by the supply pressure of the paint T from the switch 24 as described above. Is maintained at a positive pressure, thereby preventing external gas from infiltrating into the filling chamber 10 in the filling step or bubble formation of gas dissolved in the paint T.

  (C) When the filling step is completed, as shown in FIG. 5 as the bubble presence / absence determination step, the determination unit 38a as bubble presence / absence determination means in the pump controller 38 closes the paint supply valve Va and dump valve vb and switches Under the condition that the fluid supply from the vessel 24 is stopped, the piston rod 5 is advanced to press the piston 4 to slide the piston 4 toward the one side bottom wall 7 by the predetermined pressure transfer amount e. Air bubbles in the paint T filled in the filling chamber 10 based on the change form of the measured load torque m at this time (ie, the change form of the measured load torque m indicating the change form of the paint pressure in the filling chamber 10) Determine if it exists.

  That is, when air bubbles do not exist in the paint T in the filling chamber 10, when the piston 4 is moved to the side of the one side bottom wall 7, the pressure of the paint T in the filling chamber 10 When bubbles are present in the paint T in the filling chamber 10, while rising quickly, even if the piston 4 is moved to the side of the one side bottom wall 7, the paint in the filling chamber 10 because of the compressibility of the bubbles. The pressure at T rises only slowly.

  From this, when the piston 4 is slid toward the one-side bottom wall 7 by the predetermined moving amount for pressurization e, the determination unit 38a determines that the increase in the measured load torque m is quick. When it is determined that there is no air bubble in the paint T in the case, and the shift to the next discharge step is permitted, while the piston 4 is slid toward the one side bottom wall 7 by a predetermined moving amount for pressurization e. When the increase in measured load torque m is slow, it is determined that air bubbles are present in the paint T in the filling chamber 10, and the transition to the next discharge step is prohibited, and the administrator is notified of the necessity of measures. Issue an alert.

  In addition, when the determination section 38a as the bubble presence / absence determination means determines that there is no bubble, the piston rod 5 is retracted by a predetermined amount before moving to the discharge step, and the pressure of the paint T in the filling chamber 10 causes the piston 4 to Is returned to the side away from the one-side bottom wall 7 by a predetermined amount of movement, the pressure of the paint T in the filling chamber 10 is reduced to a pressure suitable for supplying the paint to the coating machine 1.

  (D) If it is determined in the bubble presence / absence determination step that no bubbles are present from the determination unit 38a, as shown in FIG. 6 as the discharge step, the paint supply valve Va is opened with the dump valve Vb closed, The piston 4 is caused to slide toward the one side bottom wall 7 at a predetermined speed until the piston 4 abuts against the projecting pin 25 on the one side bottom wall 7 by pressing by the rod 5, whereby the need for the metering in the previous filling step A supply amount of used paint T is supplied to the coating machine 1 through the discharge hole 12 and the discharge passage 20.

  (E) When the discharge process is completed, the paint supply valve Va is closed and the dump valve Vb and the saver valve Vc are opened at the beginning of the cleaning process, and the piston 4 is brought into contact with the projecting pin 25 by the piston rod 5 While being held in the state, the cleaning solution L is supplied from the switch 24 to the filling chamber 10 through the filling passage 23, whereby the used paint T remaining in the filling passage 23, the bottom gap 26 and the annular gap 27 is washed away Together with L, it is collected in the collection container 22 through the collection passage 21.

  Thereafter, as shown in FIGS. 7 and 8, the piston rod 5 is moved backward until the tip of the piston rod 5 is retracted into the rod through hole 16 of the seat member 14 on the other side bottom wall 9 side, With the supply valve Va and the dump valve Vb closed, by continuing the supply of the cleaning liquid L from the switch 24, the piston 4 is slid to the contact position with the seat member 14 by the supply pressure of the cleaning liquid L. The filling chamber 10 is filled with the cleaning liquid L.

  Then, in a state in which the piston 4 is held in the contact position to the seat member 14 by the filling of the filling chamber 10 with the cleaning liquid L, the on-off valve V2 in the sealing liquid supply passage 35 is closed and the on-off valve in the cleaning supply passage 33 The cleaning liquid L is supplied from the cleaning / drying machine 31 for the gap portion as the cleaning / drying means in a state where the on / off valve V3 in V1 and the cleaning discharge path 37 is opened, the cleaning liquid L is supplied to the cleaning supply path 33 → The flow passage portion 34 around the piston rod 5 in the rod through holes 15 and 16 of the other bottom wall 9 and the seat member 14 → relay chamber 28 → communication passage 30 → the clearance portion 29 → the central mounting hole 8a of the connecting member 8 The passage portion 36 around the other side bottom wall 9 and the seat member 14 and the discharge passage 37 for cleaning are passed in this order.

  That is, the cleaning solution L is allowed to pass through the gap portion 29 between the cylinder inner peripheral surface 3a and the piston 4 on the side opposite to the filling chamber 10 with respect to the annular sealing material 13 by this cleaning solution supply. In the form, the clearance 29 is washed.

  Further, following the cleaning process for the gap portion 29, the drying gas A is supplied from the cleaning / drying device 31 for the gap portion as the cleaning / drying means, whereby the drying gas A is transferred to the gap portion 29 after cleaning. Similarly, the clearance 29 after the cleaning is subjected to a drying process in the form of being temporarily passed.

  Furthermore, as shown in FIGS. 9 and 10, following the above-described cleaning and drying process for the clearances 29, the cleaning supply passage 33 is maintained while the piston 4 is held in the contact position with respect to the seat member 14. The on-off valve V1 in the case and the on-off valve V3 in the cleaning discharge passage 37 are closed, and the on-off valve V2 in the sealing liquid supply passage 35 is opened. By supplying the seal liquid S having the lubricating property, the seal liquid S is flowed from the seal liquid supply path 35 to the other side bottom wall 9 and the flow passage portion around the piston rod 5 in the rod through holes 15 and 16 of the seat member 14 respectively. The pressure is supplied to the gap portion 29 through the relay chamber 28 through the communication passage 30.

  That is, by supplying the sealing liquid S to the gap portion 29 in this manner, the sealing liquid S is supplied to the space between the inner peripheral surface 3 a of the cylinder 3 adjacent to the gap portion 29 and the outer peripheral surface of the annular sealing member 13. The sealing function and the lubricating function are applied to the seal portion, whereby the components contained in the paint T previously filled in the filling chamber 10 (particularly, the curing components contained in the paint T, etc.) are cleaned by the cleaning liquid L. Even if it remains on the inner peripheral surface of the cylinder 3 or the outer peripheral surface of the annular seal member 13 as an adhesion residue formed into a film regardless of that, the increase in piston sliding resistance caused by the adhesion residue is suppressed and the pump function is good To be able to keep

  Incidentally, the seal liquid S supplied from the seal liquid supply device 32 for the gap portion has an effective sealing function and a lubricating function also to the seal portion between the other side bottom wall 9 and the piston rod 5 penetrated therethrough. Do.

  (F) In the second half of the cleaning and drying process for the filling chamber 10, as shown in FIG. 11, the drying gas A is changed from the switch 24 to the cleaning liquid L and supplied to the filling chamber 10 through the filling passage 23. The dump valve Vb and the saver valve Vc are opened in a state in which the paint supply valve Va is closed, and in this state, the piston rod 5 is moved forward to push the piston 4 by the piston rod 5. The cleaning fluid L remaining in the filling passage 23 and the filling chamber 10 is discharged to the recovery container 22 through the recovery passage 21 by extrusion with the drying gas A.

  Then, after the drying process, the supply of the drying gas A from the switch 24 is stopped, thereby leaving the bottom gap 26 and the annular gap 27 between the one side bottom wall 7 and the piston 4. , And returns to the state provided at the start of supply of the next used paint T from the switch 24 (FIG. 1).

[Another embodiment]
Next, another embodiment of the present invention will be listed.

  FIG. 12 shows an example in which a syringe pump 2 ′ for supplying a curing liquid is juxtaposed to the syringe pump 2 for supplying a coating material T to the coating machine 1 and the syringe pump for supplying the curing liquid. 2 'mixes the curing liquid K with the paint T passing through the discharge passage 20 in parallel with the paint supply from the paint supply syringe pump 2 to the coating machine 1.

  The syringe pump 2 'for supplying the curing liquid has the same structure as the syringe pump 2 for supplying the paint, and the same function as each part of the syringe pump 2 for supplying the paint in the syringe pump 2' for supplying the curing liquid. The same reference numerals as used in the paint supply syringe pump 2 are attached to the parts that perform the above.

  In addition, a bubble removing step of passing the curing liquid K supplied from the switch 24 'through the bottom gap 26' and the annular gap 27 'to remove the residual gas in the filling chamber 10', and moving the piston 4 'by a predetermined pressure A bubble presence / absence judgment step of judging presence / absence of air bubbles in the curing liquid K in the filling chamber 10 'based on the change form of the measured load torque m' when sliding it to the side of the one bottom wall 7 'by the amount e; Also, in a state where the piston 4 'is in contact with the seat member 14', the seal liquid supply device 32 'for the gap portion as the seal liquid supply means opposes the annular seal member 13' to the filling chamber 10 '. The same pump controller 38 is also used for each step such as the seal liquid supply step of supplying the seal liquid S 'having lubricity to the gap portion 29' between the inner peripheral surface of the cylinder 3 'and the piston 4' on the side. Is the same as the syringe pump 2 for paint supply To run like.

  In the above-mentioned embodiment, although the example which made the seat member 14 the independent member different from the other side bottom wall 9 was shown, it may be replaced with this, and the structure which combines the other side bottom wall 9 with the seat member 14 may be used. .

  The liquid to be discharged by the syringe pump of the present invention (that is, the liquid to be filled in the filling chamber 10) is not limited to the liquid paint T and the curing liquid K for paint, and there may be adhesion residue As long as it is a liquid, it may be a liquid for any application.

  In addition, the sealing liquid S supplied to the gap portion 29 between the inner circumferential surface 3a of the cylinder and the annular sealing material 13 on the side opposite to the filling chamber 10 with respect to the annular sealing material 13 has lubricity. Also, any sealing liquid may be used as long as it does not adversely affect the application of the liquid T.

  Furthermore, the structure of the flow channel for guiding each of the cleaning liquid L, the drying gas A and the sealing liquid S to the gap 29 is not limited to the flow channel structure shown in the above embodiment, and various flow channel structures are adopted. be able to.

  The present invention can be utilized in a syringe pump used for various applications in various fields.

Reference Signs List 3 cylinder 4 piston 3 a cylinder inner circumferential surface 13 annular seal member 23 filling passage 7 one side bottom wall 10 filling chamber T paint (liquid)
20 Discharge path 2 Syringe pump 29 Gap part L Cleaning solution A Drying gas 31 Cleaning dryer for gap part (washing and drying means)
S Seal fluid 32 Seal fluid supply device for gap part (seal fluid supply means)
33 cleaning supply path 37 cleaning exhaust path 35 seal fluid supply path V1 to V3 on-off valve 38 pump controller (control means)
14 seat member 28 relay chamber 30 communication passage e moving amount for pressurization 38a determination unit (bubble presence / absence determination means)

Claims (5)

The piston slidably disposed inside the cylinder is equipped with an annular seal member for sealing between the piston and the inner circumferential surface of the cylinder,
A syringe which discharges the liquid filled in the filling chamber between the one bottom wall of the cylinder and the piston through the filling passage from the filling chamber through the discharge passage by the sliding of the piston toward the one side bottom wall A pump,
A cleaning solution is supplied to a gap between the piston and the inner peripheral surface of the cylinder on the side opposite to the filling chamber with respect to the annular seal member to clean the gap, and the gap after cleaning There is provided a washing / drying means for supplying a drying gas to the part to dry the gap after washing, and
A syringe pump provided with a sealing liquid supply means for supplying a sealing liquid having lubricity to the clearance portion following the cleaning and drying processing of the clearance portion by the cleaning and drying means. A cleaning supply passage for guiding the cleaning solution and the drying gas to the gap portion; a cleaning discharge passage for discharging the cleaning solution and the drying gas supplied to the gap portion from the gap portion; An on-off valve is provided in each of the seal liquid supply path leading to the gap portion,
Control means for controlling the cleaning and drying means and the sealing liquid supply means is, as on-off valve control for opening and closing each on-off valve,
When the cleaning liquid and the drying gas are supplied to the gap portion, the on-off valve provided in the seal liquid supply passage is closed, and the cleaning supply passage and the cleaning discharge passage are provided. Open the on-off valve,
When the seal liquid is supplied to the gap portion, the on-off valve provided on each of the cleaning supply path and the cleaning discharge path is closed, and the on-off valve provided on the seal liquid supply path is opened. The syringe pump according to claim 1, wherein the syringe pump is configured. A seat member is provided to abut and stop the piston sliding to a side away from the one side bottom wall;
The piston and the seat member have a structure in which a relay chamber is formed between the piston and the seat member when the piston abuts on the seat member.
The piston is provided with a communication passage for connecting the relay chamber to the gap portion,
The cleaning and drying means and the sealing liquid supply means are configured to supply the cleaning liquid, the drying gas, and the sealing liquid to the clearance through the relay chamber and the communication passage. Syringe pump.   After the filling chamber is filled with the liquid through the filling passage, and the filling passage and the discharge passage are closed, the piston is pressed by a piston rod by a predetermined moving amount for pressurization by the side of the one bottom wall The air bubble is slidingly moved to detect the pressure change of the liquid in the filling chamber at that time, and based on the detected pressure change, it is determined whether the liquid in the filling chamber contains bubbles or not. The syringe pump according to any one of claims 1 to 3, further comprising presence determination means.   The bubble presence / absence determination means is configured to return and slide the piston away from the one side bottom wall by the pressure of the liquid in the filling chamber after detecting a change in pressure of the liquid in the filling chamber. The syringe pump according to claim 4.

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