Liquid discharge device, container for that substance, and method of containerization.

Abstract

The current invention involves dropping liquid and enhancing its ability. Operation of discharge procedures in liquid material discharge devices (20) including The nozzle assembly (35) is fitted with an outlet opening (33) through which the liquid material is released. Through that channel, the switching valve (51) is connected to the injector assembly (35) and the regulator. Release, the release device also includes an additional pressure-generating section (60) with a pressure-generating channel. The pressure (62) under which the liquid material under pressure is supplied to the switching valve (51) and Negative pressure section (70) which includes the diversion channel (72) in which the pressure can be set to a relatively low value. The pressure in the pressure channel is lowered, causing the switch valve (51) to be moved between positions. One of the openings is the release port (33), which is connected to the pressure-generating port (62) and the opening. The release (33) is cut off from the diversion channel (72), and the second position of the release opening (33) It is connected to the diversion channel (72) and the discharge opening (33) is cut off from the pressure-generating channel. (62);

Description

[0001] The present invention relates to a liquid material dispensing device, a coating device, and a coating method that dispense liquid materials ranging from low viscosity liquid materials to high viscosity liquid materials such as solder paste, silver paste, and adhesives, in a quantitative manner, regardless of the filler content.

[0002] Conventionally, screw-type dispensing devices are known in which a screw is formed on the surface of a rod-shaped body in a spiral shape along the longitudinal direction of the rod-shaped body, and the rotation of this screw causes the flange to transport and discharge the liquid. The applicant has also disclosed in Patent Document 1 a screw-type dispensing device that dispenses a fixed amount of liquid, and in particular a device that dispenses liquid containing fillers with high precision.

[0003] The discharge device of Patent Document 1 shown in Figure 14 is a screw-type liquid material discharge device 10 that discharges liquid by the rotation of the screw 7, comprising a screw 7 having spiral blades on the surface of a rod 8 extending longitudinally from the tip, a motor 9 (rotational drive mechanism) for rotating the screw 7, a main body 1 having a liquid inlet 4 for supplying liquid material, a screw through-hole 2 through which the screw 7 passes, and a housing 5 covering the discharge port end of the screw 7, and a nozzle 6 attached to the tip of the housing 5 and communicating with the inside of the housing 5. In this discharge device 10, it is proposed as a preferred embodiment that the gap between the screw 7 and the inner wall surface of the housing 5 be wider than the particle size of the filler or the particle size of the filler cluster.

[0004] Another form of discharge device is a jet-type discharge device that uses a rapidly advancing plunger to impart inertial force to a liquid material, causing it to be ejected from the discharge port in the form of separated droplets. As an example of a dispensing device in which a plunger is seated when a droplet is discharged, there is a droplet metering dispensing device proposed by the applicant in Patent Document 2, in which a switching valve is in a first position and the plunger rod is moved backward by valve operating air to open the discharge port, and a switching valve is in a second position and the plunger rod, which has been moved forward by a plunger rod extension means, is brought into contact with the valve seat to stop rapidly and discharge the liquid in droplet form from the discharge port of the valve.

[0005] Japanese Patent Publication No. 2002-326715, Japanese Patent No. 4663894

[0006] (a) A discharge device that rotates and discharges a screw having spiral blades extending longitudinally from the tip on the surface of a rod, or (b) a discharge device that discharges a liquid material by rotating or advancing the rod. In a discharge device in which the discharge port and the liquid material supply source remain in communication even during the standby period of the discharge operation, there is a problem of liquid leakage in which the liquid material leaks from the discharge port during the standby period of the discharge operation. For example, in the discharge device 10 disclosed in FIG. 14, since a gap is provided between the screw and the inner wall surface of the housing, the liquid material may leak from the discharge port through the gap during the standby period of the discharge operation. This problem appears prominently when discharging a liquid material with a low viscosity.

[0007] In order to solve such a problem, Patent Document 1 proposes applying pressure to the liquid material in a pulsed manner during discharge, and applying a negative pressure to the liquid material in the storage container during the discharge standby period to prevent the liquid material from dripping from the tip of the nozzle.

[0008] However, the method of applying pressure to the liquid material in a pulsed manner (that is, the method of applying pressure to the liquid material by sending air into the space in the storage container for each discharge) has a problem that it takes time until the residual pressure in the liquid chamber communicating with the discharge port is released due to the compressibility of air. Since this problem causes a decrease in productivity, it has been required to shorten the time required for releasing the residual pressure in the liquid chamber.

[0009] An object of the present invention is to provide a discharge device, a coating device, and a coating method that can effectively solve the problem of liquid leakage and further improve the workability of the discharge operation.

[0010] The present invention relates to a liquid material dispensing device, and is characterized in that the liquid material dispensing device comprises a discharge port for dispensing a liquid material, a liquid chamber communicating with the discharge port and supplied with the liquid material, a thrust-generating member disposed in the liquid chamber and providing the thrust necessary for dispensing the liquid material, a thrust-generating member drive source for operating the thrust-generating member, and a discharge control unit, wherein the device is provided with a pressurizing section having a pressurizing channel for supplying pressurized liquid material into the liquid chamber, a negative pressure section having a retraction channel that can be set to a pressure relatively lower than the pressure in the liquid chamber, a liquid valve section having a liquid material supply port communicating the liquid chamber and the pressurizing channel, and a liquid material opening port communicating the liquid chamber and the retraction channel, and the liquid valve section is provided with a switching valve that switches between a first position that communicates the liquid chamber and the liquid material supply port and blocks the liquid chamber and the liquid material opening port, and a second position that communicates the liquid chamber and the liquid material opening port and blocks the liquid chamber and the liquid material supply port. The present invention relating to the above-described liquid material dispensing device may be characterized in that the pressurizing section comprises a liquid storage container and a pressurizing source that supplies pressurized air to the liquid storage container, and the negative pressure section comprises a negative pressure source that communicates directly or indirectly with the retraction channel. Preferably, the negative pressure section comprises a liquid material retraction container with a diameter larger than that of the retraction channel. More preferably, the negative pressure section comprises a discharge channel for discharging the liquid material stored in the retraction container. Even more preferably, the negative pressure section comprises a discharge channel opening / closing mechanism that connects or blocks the discharge channel from the outside. In the present invention, which includes this discharge channel opening / closing mechanism, the negative pressure section may be characterized by comprising a pressurizing source that supplies pressurized air to the retractable container, and a negative pressure section switching valve having a pressurized position that connects the pressurizing source and the retractable container, and a depressurized position that connects the negative pressure source and the retractable container. Preferably, the discharge channel opening / closing mechanism is an opening / closing valve, the pressurizing section comprises a pressurizing section opening / closing valve that connects or blocks the pressurizing section and the liquid valve section, and the discharge control unit closes the pressurizing section opening / closing valve, sets the negative pressure section switching valve to the pressurized position, opens the discharge channel opening / closing mechanism, and discharges the liquid material in the retractable container to the outside according to predetermined discharge conditions. The discharge conditions referred to herein include discharge at regular intervals and discharge at regular intervals.

[0011] In the present invention, which includes the above-described retraction container, the negative pressure section may be characterized by comprising an elongated negative pressure adjustment pipe arranged inside the retraction container, with one opening of the negative pressure adjustment pipe communicating with the retraction passage and the other opening of the negative pressure adjustment pipe being located in the space inside the retraction container. In the present invention, which includes the above-mentioned pressurized source and negative pressure source, the discharge control unit may be characterized in that, during discharge standby, it applies a negative pressure from the negative pressure source to the retraction channel necessary to prevent liquid dripping from the discharge port, and at the end of discharge, it applies a stronger negative pressure from the negative pressure source to the retraction channel than during discharge standby. In the present invention, which includes the above-mentioned pressurized source and negative pressure source, the discharge control unit may be characterized in that, during discharge operations, it applies the pressurized force from the pressurized source to the liquid storage container necessary to discharge the liquid material from the discharge port, and during discharge standby, it applies a stronger pressurized force from the pressurized source to the liquid storage container than during discharge operations. In the present invention relating to the liquid material discharge device described above, the thrust-applying member may be a screw that rotates and has a smaller diameter than the liquid chamber, or a rod-shaped member that imparts inertial force to the liquid material by rapid advancement, or the thrust-applying member may be a male helical rod that rotates eccentrically, the liquid chamber may have a female helical inner wall surface that cooperates with the thrust-applying member, and the thrust-applying member and the liquid chamber may constitute a single-axis eccentric screw pump mechanism.

[0012] The present invention relates to a liquid material dispensing device, and comprises a nozzle member having a discharge port for dispensing a liquid material, a switching valve communicating with the nozzle member, and a discharge control unit, wherein the switching valve is provided with a pressurized section having a pressurized passage for supplying pressurized liquid material to the switching valve, and a negative pressure section having a retraction passage that can be set to a pressure relatively lower than the pressure in the pressurized passage, the switching valve constitutes a liquid valve section having a liquid supply port communicating with the discharge port, a liquid material supply port communicating with the pressurized passage, and a liquid material opening port communicating with the retraction passage, the switching valve is characterized by switching between a first position that communicates the discharge port and the pressurized passage and blocks the discharge port and the retraction passage, and a second position that communicates the discharge port and the retraction passage and blocks the discharge port and the pressurized passage, preferably the liquid valve section and the nozzle member are communicated via a flexible tube.

[0013] The present invention relates to a coating apparatus comprising the above-mentioned liquid material dispensing device, a work table on which an object to be coated is placed, an XYZ drive mechanism for moving the liquid quantitative dispensing device and the work table relative to each other, and a drive mechanism control unit for controlling the operation of the XYZ drive mechanism.

[0014] The present invention relates to a coating method, and is a method for coating a liquid material using a coating apparatus comprising: a liquid material dispensing device; a work table on which an object to be coated is placed; an XYZ drive mechanism for relatively moving the liquid quantitative dispensing device and the work table; and a drive mechanism control unit for controlling the operation of the XYZ drive mechanism, wherein the dispensing control unit, during the dispensing operation, operates a thrust-applying member with the switching valve of the liquid valve unit in the first position to discharge the liquid material from the discharge port, and when the discharge is completed, stops the operation of the thrust-applying member and switches the switching valve unit of the liquid valve unit to the second position to stop the discharge of the liquid material from the discharge port. The present invention relates to a coating method, and is a method for coating a liquid material using a coating apparatus comprising: a liquid material dispensing device equipped with a pressurizing source and a negative pressure source; a work table on which an object to be coated is placed; an XYZ drive mechanism for relatively moving the liquid quantitative dispensing device and the work table; and a drive mechanism control unit for controlling the operation of the XYZ drive mechanism, wherein the dispensing control unit, during the dispensing operation, operates a thrust-applying member with the switching valve of the liquid valve unit in the first position to discharge the liquid material from the discharge port, and when the discharge is completed, stops the operation of the thrust-applying member and switches the switching valve unit of the liquid valve unit to the second position. The discharge of liquid material from the discharge port is stopped by doing so, and during the discharge standby period, the negative pressure source provides the necessary negative pressure to the retraction channel to prevent dripping from the discharge port, and at the end of discharge, the negative pressure source provides a stronger negative pressure to the retraction channel than during the discharge standby period. Preferably, the discharge control unit provides the necessary pressurizing force to the liquid storage container from the pressurizing source during the discharge operation to discharge the liquid material from the discharge port, and during the discharge standby period, the pressurizing source provides a stronger pressurizing force to the liquid storage container than during the discharge operation.

[0015] The present invention relates to a coating method, and is a method for coating a liquid material using a coating apparatus comprising: a liquid material dispensing device equipped with the above-mentioned discharge channel opening / closing mechanism, the above-mentioned negative pressure section switching valve, and the above-mentioned pressurized section opening / closing valve; a work table on which an object to be coated is placed; an XYZ drive mechanism for relatively moving the liquid quantitative dispensing device and the work table; and a drive mechanism control unit for controlling the operation of the XYZ drive mechanism, wherein the discharge control unit, during the dispensing operation, operates a thrust-applying member with the switching valve of the liquid valve section in the first position to discharge the liquid material from the discharge port, and when the discharge is completed, stops the operation of the thrust-applying member and switches the switching valve section of the liquid valve section to the second position to stop the discharge of the liquid material from the discharge port, and according to predetermined discharge conditions, closes the pressurized section opening / closing valve, sets the negative pressure section switching valve to the pressurized position, opens the opening / closing valve constituting the discharge channel opening / closing mechanism, and discharges the liquid material in the retractable container to the outside. The discharge conditions referred to herein include discharging at regular intervals and discharging at regular intervals.

[0016] According to the present invention, it is possible to provide a dispensing device, a coating device and a coating method thereof that can effectively solve the problem of dripping and further improve the workability of the dispensing operation.

[0017] This is a schematic cross-sectional view of the main part illustrating the pressure state in the flow path of the discharge device according to the first embodiment, where (a) shows the discharge operation and (b) shows the discharge standby state. This is a schematic cross-sectional view of the main part illustrating the pressure state in the flow path of a conventional discharge device, where (a) shows the discharge operation and (b) shows the discharge standby state. This is a schematic perspective view of the liquid material discharge device according to Example 1. This is a schematic perspective view of a coating device equipped with the liquid material discharge device according to Example 1. This is a schematic top view of the liquid material discharge device according to Example 1. This is a cross-sectional view of the main part of the liquid material discharge device according to Example 1, illustrating the first position of the switching valve. This is a cross-sectional view of the main part of the liquid material discharge device according to Example 1, illustrating the second position of the switching valve. This is a cross-sectional view of the main part illustrating the negative pressure section of the liquid material discharge device according to Example 1. This is an explanatory diagram illustrating the liquid material discharge device according to Example 2. This is a cross-sectional view of the main part illustrating the negative pressure section of the liquid material discharge device according to Example 2. This is a cross-sectional view of the main part illustrating the negative pressure section of the liquid material discharge device according to Example 3. This is a cross-sectional view of the main part illustrating the liquid material discharge device according to Example 4. This is an overall configuration diagram of the liquid material discharge device according to Example 5. Figure 2 of Patent Document 1 is a cross-sectional view of the main part of a conventional discharge device. This is a schematic cross-sectional view of the main part illustrating the pressure state in the flow path of a discharge device according to a second embodiment, where (a) shows the discharge operation and (b) shows the discharge standby state.

[0018] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following, for the sake of convenience of explanation, the storage container 12 side may be referred to as the upward direction and the nozzle 33 side as the downward direction. <Configuration of the first embodiment> Figure 1 is a schematic cross-sectional view of the main part illustrating the pressure state in the flow path of the discharge device 20 according to the first embodiment, where (a) shows the discharge operation and (b) shows the discharge standby state. As shown in Figure 1, the liquid material discharge device 20 according to the first embodiment mainly consists of a discharge unit 30, a liquid valve section 50, a pressurizing section 60, and a negative pressure section 70. In Figure 1, the liquid material 25 under the same pressure as the liquid chamber 32 is colored a dark color, and the liquid material 25 under a different pressure than the liquid chamber 32 is colored a light color.

[0019] The discharge unit 30 includes a rod 31 which is a thrust-applying member, a liquid chamber 32 through which the rod is inserted, a discharge port 33 provided at the lower end of a nozzle that communicates with the liquid chamber 32, a liquid material supply port 34 that communicates with the side surface of the liquid chamber 32, and a rod drive source 37 that rotates the rod 31. In the first embodiment, a rod-shaped member is exemplified as the shape of the thrust-applying member, but it is not limited thereto, and various members that apply a mechanical action such as forward and backward movement, parallel movement or vibration to the liquid chamber bottom opening 38 can be applied. In particular, the present invention is suitable for a type of discharge device in which the thrust-applying member does not block the liquid chamber bottom opening 38 when it is in discharge standby mode. This type of discharge device also includes a jet-type discharge device in which the thrust-applying member sits on the bottom surface of the liquid chamber and divides the liquid material.

[0020] The liquid valve section 50 is equipped with a switching valve 51. The switching valve 51 in the first embodiment includes a flow path A81 directly connected to the discharge unit 30, a flow path B82 that functions as a pressurized flow path, a flow path C83 that functions as a retraction flow path, and a valve body 55 that switches the communication between flow path A81 and flow paths B82 and C83. The switching valve 51 is a three-way valve that can switch the communication between the pressurized section 60 and the liquid chamber 32 or the negative pressure section 70 and the liquid chamber 32, but the type and structure of the valve are not limited. For example, a valve that moves the valve body back and forth with an electromagnetic motor or an air motor, or a valve that deforms a diaphragm with a solenoid drive unit can be used. The operation of the switching valve 51 will be described later. In Figure 1, the gap between the liquid chamber 32 and the rod 31 is set to be wide, but as shown in Figure 14, the gap between the liquid chamber 32 and the rod 31 may be set to be narrower to generate a stronger liquid thrust force due to the operation of the rod 31.

[0021] The pressurized section 60 comprises a storage container 12, a pressurized passage 62 connecting the storage container and the liquid valve section 50, and a pressurizing device (not shown) for pressurizing the storage container. Here, the pressurized passage 62 may be made of a flexible tube or may be formed in a member that can be attached to and detached from the storage container 12 (for example, a liquid transfer block described later). The storage container 12 is not limited to the shape shown and can be of any shape. In the discharge device 20 of the first embodiment, the upper space inside the storage container 12 is in communication with a pressurizing device (not shown).

[0022] The negative pressure section 70 is provided with a retraction channel 72 having an end opening 74. The end opening 74 of this retraction channel is open to the atmosphere or communicates with a negative pressure generating device (not shown). Preferably, a negative pressure generating device is provided, and the liquid material in the retraction channel 72 is pre-adjusted to a desired pressure and prepared so that the desired pressure is quickly applied to the liquid material in the liquid chamber 32 immediately after the switching operation of the switching valve 51. Preferably, the receptacle channel 72 has an inner diameter that is sufficiently larger than the inner diameter of the discharge port 33 over its entire length. More preferably, a receptacle container with a diameter larger than the receptacle channel 72 is provided between the end opening 74 of the receptacle channel and the negative pressure generating device (not shown). This receptacle container can take any shape as long as it has a diameter larger than the receptacle channel 72, but from the viewpoint of installation space, a tubular shape is disclosed as an example of a preferred configuration (see receptacle pipe 76 described later).

[0023] <Conventional configuration and operation> Figure 2 is a schematic cross-sectional view of the main components illustrating the pressure state within the flow path of a conventional discharge device, where (a) shows the discharge operation and (b) shows the discharge standby state. The conventional discharge device 10 shown in Figure 2 has the same discharge unit configuration as the first embodiment, but differs from the first embodiment shown in Figure 1 in that the discharge unit communicates with the storage container 12 without going through the switching valve 151. Also, the switching valve 151 of the discharge device in Figure 2 differs from the switching valve 51 of the first embodiment, which switches the flow path of liquid, in that it is a valve that switches the flow path of gas.

[0024] In the discharge device 10, as in the first embodiment, the liquid material in the liquid chamber 32 is discharged from the discharge port 33 by the rotational motion of the rod 31. As shown in Figure 14, the gap between the liquid chamber 32 and the rod 31 may be set to be narrow so that a strong liquid propulsion force is generated by the operation of the rod 31. During the discharge operation, as shown in Figure 2(a), the storage container 12 is in communication with pipe B17 via adapter 14, pipe A16, and switching valve 151, and is subjected to pressurization from pipe B17. That is, the valve body 155 of the switching valve 151 takes the first position which connects pipe A16 and pipe B17, and pressurized air regulated to the desired pressure upstream of pipe B17 is supplied to the upper space inside the storage container 12 via pipe A16.

[0025] When the discharge operation is completed, as shown in Figure 2(b), the operation of the rod drive source 37 is stopped to stop the movement of the rod 31, and the valve body 155 of the switching valve 151 is switched to the second position which connects pipe A16 and pipe C18. The inside of pipe C18 is pressurized so that negative pressure is generated in the storage container 12, and when the switching valve 151 is switched to the second position, the pressurized air inside pipe A16, adapter 14 and storage container 12 flows rapidly toward pipe C18. As a result, the air pressure inside the storage container 12 decreases, and the pressure effect on the liquid material 25 inside the storage container 12 also decreases, so that the liquid material is no longer discharged from the discharge port 33.

[0026] When the discharge is in standby mode, the switching valve 151 holds in the second position, so that pipes A16 and C18 are in communication, and negative pressure is supplied into the storage container 12, preventing the liquid material from dripping out of the discharge port 33. Thus, the conventional dispensing device 10 prevents dripping of liquid material during dispensing and while waiting for dispensing by pressurizing or depressurizing the upper space inside the storage container 12. However, the conventional discharge device 10 has the problem of a response delay due to the compressibility of the gas. This response delay problem occurs not only when the switching valve 151 is in the first position, but also when it is in the second position.

[0027] In contrast, in the discharge device 20 of the present invention, pressure is transmitted to the liquid chamber 32 by the liquid material 25, so there is no problem of response delay when switching the switching valve 51. The position switching of the switching valve 51 in the first embodiment will be described in detail below with reference to Figure 1.

[0028] <Switching operation of the first embodiment> During the discharge operation, as shown in Figure 1(a), the switching valve 51 takes the first position which connects the pressurized passage 62 and the passage A81, and the liquid material 25 is supplied from the storage container 12 to the liquid chamber 32. Here, the storage container 12 is connected to a pressurizing device (not shown), and the upper space inside the storage container 12 is constantly pressurized to a desired pressure. During the discharge operation, the communication between the retraction passage 72 and the liquid chamber 32 is blocked.

[0029] When the discharge operation is completed, as shown in Figure 1(b), the operation of the rod drive source 37 is stopped to stop the movement of the rod 31, and the switching valve 51 is switched to the second position which connects the retraction passage 72 and the passage A81. The retraction passage 72 is pressure-regulated so that negative pressure is generated in the liquid chamber 32, and when the switching valve 51 is switched to the second position, the liquid material in the passage A81 and the liquid chamber 32 flows rapidly toward the retraction passage 72. In other words, the liquid material 25 in the retraction passage 72 is at a lower pressure than the liquid material 25 in the passage A81 and the liquid chamber 32, so when the switching valve 51 is switched from the first position to the second position, a force is generated that pulls the liquid material in the passage A81 and the liquid chamber 32 toward the retraction passage 72. As a result, the liquid pressure in the liquid chamber 32 decreases, and the liquid material is no longer discharged from the discharge port 33.

[0030] Here, it is disclosed that it is preferable to change the negative pressure acting on the liquid chamber 32 between the end of discharge and the discharge standby period. Specifically, it is disclosed that a strong negative pressure is generated in the receptacle channel 72 during the discharge operation in order to generate a strong pull-back effect immediately after the end of the discharge operation, thereby applying a strong negative pressure at the end of discharge, and a weaker, appropriate negative pressure (i.e., a negative pressure to prevent dripping) is generated in the receptacle channel 72 during the discharge standby period after the end of discharge.

[0031] In addition, in the discharge device 10 of the first embodiment, since the communication between the storage container 12 and the liquid chamber 32 is blocked when the device is in discharge standby mode, the pressure of the pressurized air supplied to the storage container 12 can be made different during discharge operation and when the device is in discharge standby mode. That is, in discharge standby mode, the pressure applied to the storage container 12 is adjusted to a desired pressure (a relatively higher pressure compared to when the device is in discharge operation), so that the optimal pressure can be quickly supplied to the liquid chamber 32 immediately after the switching operation of the switching valve 51.

[0032] In this first embodiment, the pressure in the liquid chamber communicating with the discharge port is adjusted by utilizing the pressure difference of an incompressible liquid material. Therefore, the responsiveness of the switching valve is significantly better than that of conventional discharge devices that utilize the pressure difference of a gas. Furthermore, the good responsiveness of pressurization and depressurization contributes to improving the quality and productivity of the discharge operation. During discharge standby, dripping from the discharge port can be prevented.

[0033] <Configuration of the second embodiment> Figure 15 is a cross-sectional side view of the main part illustrating the liquid material dispensing device 20 according to the second embodiment. In the following, the configurations common to the first embodiment (Figure 1) will not be explained, and the different configurations will be described in detail. The liquid valve section 50 is equipped with a switching valve 51 similar to that of the first embodiment. The switching valve 51 of the second embodiment includes a flow path A81 with a connecting section 59 as an outlet, a flow path B82 that functions as a pressurized flow path, a flow path C83 that functions as a retraction flow path, a valve body 55 arranged in the switching flow path 84, and a valve body drive device (not shown) that switches communication between flow path A81 and flow paths B82 and C83 by moving the valve body 55 back and forth across flow path A81. During the discharge operation shown in Figure 15(a), the valve body 55 is located on the right side of the flow path A81, and the liquid material that flows into the flow path B82 from the liquid material supply port 53 flows out to the nozzle 35 from the liquid outlet 34. In the discharge standby state shown in Figure 15(b), the valve body 55 is located on the left side of the flow path A81, and the discharge port 33 and the end opening 74 are in communication via the retracted flow path 72, the liquid material release port 54, the switching flow path 84, the flow path A81, and the liquid inlet 34, and the pressure remaining in the flow path inside the nozzle 35 is released. The switching valve 51 illustrated in Figure 15 differs from the first embodiment in that a connecting portion 59 is provided at the lower end, and that the flow paths B82 and C83 open upward, while the flow path A81 opens downward. However, the lengths of the flow paths A81, B82, and C83 are not limited to the illustrated configuration, and there are configurations where the distance is so short that it cannot be called a flow path, and such configurations are also included in the technical concept of the present invention. Furthermore, the flow path A81 does not necessarily have to open vertically downwards; for example, it may open horizontally or diagonally downwards.

[0034] A discharge member 48 is detachably attached to the connecting portion 59 by fasteners such as screws or bolts. The upper part of the discharge member 48 is cap-shaped, and the lower part is a nozzle 35 having a narrow-diameter discharge channel. In this embodiment, the lower end of the nozzle 35 is the discharge port 33, but it is not limited to this, for example, a flexible tube may be connected to the nozzle 35, and a nozzle member having a discharge port may be connected to the other end of the flexible tube. Alternatively, a flexible tube may be connected to the connecting portion 59, and the nozzle 35 may be connected to the other end of this flexible tube. The connection between the flexible tube, the connecting portion 59, and the nozzle 35 can be made by well known connecting means (for example, joint connection, press-fit connection). The longer the length of the flexible tube, the more pronounced the advantageous responsiveness of this embodiment compared to the conventional example becomes. Furthermore, by connecting the discharge member 48 and the nozzle member to the other end of the flexible tube, it becomes possible to construct a lightweight head unit in which only the nozzle member is mounted on the XYZ drive mechanism.

[0035] The pressurizing section 60 is the same as in the first embodiment and includes a storage container 12, a pressurizing channel 62 that connects the storage container and the liquid valve section 50, and a pressurizing device (not shown) that pressurizes the storage container. The negative pressure section 70 is equipped with a retraction channel 72 having an end opening 74. The basic configuration of the negative pressure section 70 is the same as in the first embodiment, but the second embodiment differs from the first embodiment in that the retraction channel 72 is a straight pipe extending in the vertical direction.

[0036] The discharge device 20 of the second embodiment described above has significantly better responsiveness when switching the switching valve compared to conventional discharge devices that utilize the pressure difference of the gas. By connecting the discharge member 48 and the nozzle member with a flexible tube to form a lightweight head section, it is possible to improve the discharge speed and productivity by reducing the weight of the head section that moves relative to it.

[0037] The details of the present invention will be described below with reference to examples, but the present invention is not limited in any way by examples.

[0038] <Structure> Figure 3 is a schematic perspective view of a liquid material dispensing device 20 according to Example 1. The dispensing device 20 comprises a dispensing unit 30 for dispensing liquid material and a liquid transfer unit 40 for supplying and receiving liquid material from the dispensing unit 30. Figure 4 is a schematic perspective view of a coating apparatus 201 equipped with a liquid material dispensing device 20 according to Embodiment 1. The coating apparatus 201 comprises a frame 202 on which a table 207 is mounted, a relative drive unit 205 provided with a holding unit 204, and an adjustment table 208 on which an adjustment workpiece is placed. A dispensing unit 30 or a measuring unit 203 is mounted on the holding unit 204. An object to be coated 206 is placed on the table 207, and the coating operation is performed while the dispensing unit 30 and the measuring unit 203 and the table 207 are moved relative to each other in the XYZ directions. The relative drive unit 205 comprises, for example, a magnet and linear guide for a linear motor, a motor and a ball screw, and moves the dispensing unit 30 and the measuring unit 203 and the table 207 relative to each other in the XYZ directions.

[0039] Figure 5 is a schematic top view of the liquid material dispensing device 20 according to Embodiment 1. Figures 6 and 7 are cross-sectional views of the main part of the flow path of the dispensing device 20, and are cross-sectional views taken along line A-A in Figure 5. Here, Figure 6 shows the liquid valve section 50 in a first position where it connects the liquid chamber 32 and the pressurized flow path 62, and Figure 7 shows the liquid valve section 50 in a second position where it connects the liquid chamber 32 and the retraction flow path 72.

[0040] (Discharge unit) The discharge unit 30 includes a rod 31 that extends vertically, a discharge unit body 36 through which the rod 31 is inserted, a liquid chamber 32 which is a space provided inside the discharge unit body 36, a nozzle 35 having an internal flow path that communicates with the liquid chamber 32, a discharge port 33 provided at the lower end of the nozzle 35, a liquid material supply port 34 that communicates with the side surface of the liquid chamber 32, and a rod drive source 37 (not shown) that rotates the rod 31.

[0041] The liquid chamber 32 in Embodiment 1 is a vertically extending cylindrical elongated hole formed within the discharge unit body 36. A sealing member is fitted at the upper opening of the liquid chamber 32 through which the rod 31 is inserted. The lower opening of the liquid chamber 32 communicates with the internal flow path of a nozzle 35 which is detachably disposed at the tip of the discharge unit body 36. The lower part of the rod 31, which has a diameter slightly smaller than the inner diameter of the liquid chamber 32, is positioned inside the liquid chamber 32. It is preferable that the gap between the lower part of the rod 31 and the inner wall surface of the liquid chamber 32 be wider than the particle size of the filler or the particle size of the filler cluster. The lower part of the rod 31 has a helical groove or vanes on its surface and rotates within the liquid chamber 32 by a rod drive source 37 (for example, a rotational drive source such as a motor), which is not shown. As the rod 31 is rotated by the rod drive source 37, thrust is applied to the liquid material in the liquid chamber 32, and the liquid material is discharged from the discharge port 33 which opens downwards.

[0042] (Liquid transfer unit) The liquid transfer unit 40 consists of an integrally arranged liquid valve section 50, a pressurizing section 60, and a negative pressure section 70. The liquid transfer unit 40 is positioned on the side of the discharge unit 30. More specifically, the pressurizing section 60 is connected to one side of the liquid valve section 50, and the negative pressure section 70 is connected to the side of the liquid valve section 50 perpendicular to the side on which the pressurizing section 60 is connected.

[0043] The liquid valve section 50 consists of a switching valve 51 and a valve block 52, the valve block 52 being connected to the side of the discharge unit 30. More specifically, the valve block 52 is connected to the side of the discharge unit body 36, thereby connecting the liquid outlet 34 provided on the side of the discharge unit body 36 with the first opening of the flow path A81 provided on the side of the valve block 52.

[0044] The switching valve 51 is a diaphragm-type three-way valve that switches between a first position in which the discharge unit 30 and the pressurizing section 60 (storage container 12) are connected, and a second position in which the discharge unit 30 and the negative pressure section 70 (receiving pipe 76) are connected. The switching valve 51 is equipped with a dialam rod A57 and a diaphragm rod B58 on the upper part of the diaphragm 56. When the switching valve 51 takes the first position in which the diaphragm rod A57 is lowered and the diaphragm rod B58 is raised, the diaphragm 56 deforms and the pressurizing section 60 (storage container 12) and the liquid chamber 32 are connected. When the switching valve 51 takes the second position in which the diaphragm rod A57 is raised and the diaphragm rod B58 is lowered, the diaphragm 56 deforms and the negative pressure section 70 (receiving passage 72) and the liquid chamber 32 are connected.

[0045] The valve block 52 has three passages inside: passage A81, passage B82, and passage C83. The first opening of passage A81 is provided on the side of the valve block 52, and the second opening is provided on the top surface of the valve block 52. The second opening of passage A81 is selectively connected to either passage B82 (pressurized passage 62) or passage C83 (reserved passage 72) by a switching valve 51. The first opening of the flow path B82 is provided on the upper surface of the valve block 52, and the second opening is provided on the side surface of the valve block 52. The first opening of the flow path B82 communicates with the flow path A81 when the switching valve 51 is in the first position, and is blocked from the flow path A81 when the switching valve 51 is in the second position. The second opening of the flow path B82 communicates with the end opening of the pressurized flow path 62 provided on the side surface of the liquid transfer block A61.

[0046] The pressurizing section 60 is comprised of a liquid transfer block A61, a storage container 12, and a pressurizing device (not shown) that supplies adjusted pressurized air to the storage container 12. The liquid transfer block A61 has a pressurized passage 62 formed inside it. The storage container 12 and the passage B82 are connected via the pressurized passage 62, and the pressurized liquid material 25 is supplied to the liquid valve section 50.

[0047] The storage container 12 in which the liquid material is stored is detachably disposed on the liquid transfer block A61. The lower opening of the storage container 12 is in communication with the pressurized passage 62. An adapter 14 is detachably disposed on the upper part of the storage container 12, which is in communication with a pipe A16 made of a flexible tube. The liquid material 25 in the storage container 12 is supplied with pressurized air adjusted to a desired pressure via the tube provided on the adapter 14, and is in a state of being pressed toward the liquid transfer block A61.

[0048] The negative pressure section 70 mainly consists of a liquid transfer block B71, a sill pipe 76, and a negative pressure generating device (not shown). The negative pressure section 70 is maintained at a pressure lower than the pressure in the liquid chamber 32 during discharge operations, and when communicating with the liquid chamber 32, it applies relative negative pressure to the liquid material in the liquid chamber 32. The liquid transfer block B71 has a retraction channel 72 and a discharge channel 73 formed inside it. The liquid transfer block B71 is positioned on the side perpendicular to the side of the valve block 52 that is connected to the discharge unit 30 (see Figure 3).

[0049] Figure 8 is a cross-sectional view of the main part illustrating the negative pressure section 70 of the liquid material dispensing device 20 according to Embodiment 1. The sill pipe 76 is positioned at the top of the liquid transfer block B71 so as to communicate with the internal flow paths (72, 73) of the liquid transfer block B71. That is, the lower part of the sill pipe 76 is in communication with the sill flow path 72 and the discharge flow path 73 of the liquid transfer block B71 (see Figure 8). The sill flow path 72 is in communication with the liquid material opening 54 and the flow path C83 of the valve block 52. The upper part of the sill pipe 76 is in communication with one end of pipe D77. The other end of pipe D77 is in communication with a negative pressure generating device such as a vacuum pump (not shown), so that a desired negative pressure is applied to pipe D77.

[0050] The outer end of the discharge channel 73 is tightly sealed by a plug 47 that functions as a discharge channel opening / closing mechanism for communicating or blocking the discharge channel 73 with the outside. By detaching the detachable plug 47, the liquid material stored in the escape tube 76 can be discharged to the outside. By detaching the plug 47 and periodically discharging the liquid material in the escape tube 76, it is possible to prevent the liquid material from being sucked into the tube D77.

[0051] It is preferable to provide a switching valve (refer to the negative pressure section switching valve 78 described later) for switching the communication between a negative pressure generating device (not shown) and a pressurizing device (not shown) in the tube D77. This is because by reducing the pressure supplied to the adapter 14 to atmospheric pressure, switching the switching valve 51 to the first position, removing the plug 47, and supplying a pressurizing force from the pressurizing device through the tube D77, the liquid material can be quickly discharged from the escape tube 76. Such a configuration is particularly effective when discharging a highly viscous liquid material that does not flow out simply by removing the plug 47.

[0052] In the first embodiment, by arranging all of the long escape tube 76, the rectangular parallelepiped-shaped switching valve 51, and the long storage container 12 so as to extend in the vertical direction, the liquid feeding unit 40 is configured to be compact.

[0053] <Operation> The operation of the liquid material discharge device 20 according to the first embodiment will be described while referring to FIGS. 6 and 7. (During discharge) As a preparatory work, the liquid material 25 supplied from the storage container 12 is filled until it reaches the discharge port 33 through the pressurizing channel 62, the liquid valve section 50 (channel A81, channel B82), and the liquid chamber 32. A desired pressure is supplied to the storage container 12 from a pressurizing device (not shown) through the adapter 14. The switching valve section 51 is set to the first position where the pressurizing channel 62 and the liquid chamber 32 are in communication (FIG. 6), and by rotating the rod 31, the liquid material 25 in the liquid chamber 32 is discharged from the discharge port 33. At this time, the discharge amount is adjusted by adjusting the rotation speed, rotation time, and / or the air pressure applied to the storage container 12 of the rod 31.

[0054] (At the end of discharge A) The rotation of the rod 31 is stopped, and the switching valve unit 51 is set to the second position, which connects the retraction passage 72 and the liquid chamber 32. When the switching valve unit 51 is set to the second position (Figure 7), the pressure remaining in the liquid chamber 32 and passage A81 is released toward the retraction passage 72, which is regulated to a negative pressure, and the discharge of the liquid material from the discharge port is quickly terminated. In addition, since the pressure in the liquid chamber 32 and passage A81 is set to the same low pressure as the retraction passage 72 and retraction pipe 76, dripping from the discharge port 33 due to the weight of the liquid material 25 can also be prevented. At this time, since the communication between the storage container 12 and the liquid chamber 32 is blocked, the pressure supply to the storage container 12 can be continued as is, and there is no need to reduce the pressure.

[0055] (Discharge end B: Two-stage adjustment) This section describes an embodiment in which the negative pressure applied to the refrigeration channel 72 immediately after the end of discharge is set to a high pressure, and the negative pressure applied to the refrigeration channel 72 during the discharge standby period is set to a relatively low pressure. To enable the rapid release of residual pressure in the liquid chamber 32 immediately after discharge is complete, a negative pressure generator (not shown) is used during the discharge operation to apply a relatively stronger negative pressure to the retraction channel 72 compared to the discharge standby state. When the rotation of the rod 31 is stopped and the switching valve section 51 is set to the second position, the pressure remaining in the liquid chamber 32 and channel A81 is rapidly released toward the retraction channel 72 by the strong negative pressure, and the discharge of the liquid material from the discharge port is rapidly completed. After the pressure remaining in the liquid chamber 32 and channel A81 is released, a negative pressure generator (not shown) communicating with the retraction channel 72 is used to apply a relatively weaker negative pressure to the retraction channel 72 compared to the discharge operation (the negative pressure necessary to prevent dripping from the discharge port 33). This prevents dripping from the discharge port 33 due to the weight of the liquid material 25.

[0056] The discharge device 20 of Embodiment 1 described above can pressurize or depressurize the liquid material 25 in the liquid chamber 32 by switching the flow of liquid with the switching valve 51. Since the pressurization and depressurization of the liquid chamber 32 are performed via an incompressible liquid material, the response is extremely good. In addition, when the device is in standby mode for discharge, it is possible to prevent liquid from dripping from the discharge port.

[0057] Figure 9 is a cross-sectional side view of the main part for explaining the liquid material ejection device according to Example 2. Hereinafter, the description of the configuration common to Example 1 will be omitted, and mainly the different configurations will be described. The configuration of the ejection unit 30 of Example 2 is the same as that of Example 1. The liquid valve unit 50 and the pressurizing unit 60 are different from Example 1 in that they include a liquid feed block C91 and a tank 94. The liquid feed block C91 is a member that integrally forms the valve block 52 and the liquid feed block A61 of Example 1. Therefore, the switching valve 51 and the liquid feed block B71 are connected to the liquid feed block C91. The liquid feed block C91 has a flow path A81, a flow path B82, and a flow path C83 inside it. The flow path B82 functions as a retreat flow path, and the flow path C83 functions as a pressurizing flow path.

[0058] The flow path C83 communicates with the tank 94 via a tube F96 made of a flexible tube. The tank 94 is a large container in which the liquid material 25 is stored. Pressurized air adjusted to a desired pressure is supplied to the liquid material 25 stored in the tank 94 from the tube E95. The liquid material 25 pressed by this pressurized air is supplied to the flow path C83 in the liquid feed block C91 via the tube F96. Also in Example 2, as in Example 1, the pressure supplied to the tank 94 via the tube E95 may be constant, and there is no need to depressurize for each ejection.

[0059] Figure 10 is a cross-sectional view of the main part for explaining the negative pressure part 70 of the liquid material ejection device according to Example 2. The retreat tube 76 of Example 2 includes an elongated negative pressure adjustment tube 49 that extends vertically inside the retreat tube 76. The negative pressure adjustment tube 49 having a smaller diameter than the retreat tube 76 has one end opening communicating with the retreat flow path 72, and the other end opening is disposed in the space inside the retreat tube 76. In Example 2, by providing the negative pressure adjustment tube 49, the height of the liquid surface can be kept constant, so that the negative pressure supplied to the retreat tube 76 can be made constant or less regardless of the amount of the liquid material in which the negative pressure is retreated. On the other hand, in the retreat tube 76 (see FIG. 8) that does not have the negative pressure adjustment tube 49, as the amount of the liquid material stored in the retreat tube 76 increases, it is necessary to increase the negative pressure supplied from the tube D77.

[0060] When a negative pressure adjustment pipe 49 is provided, the sucked liquid material 25 flows down from the end of the negative pressure adjustment pipe 49 and is stored in the sump pipe 76. Therefore, it is sufficient to supply the negative pressure necessary to create negative pressure in the liquid material in the negative pressure adjustment pipe 49 from pipe D77. In other words, it is no longer necessary to adjust the negative pressure applied to the sump channel 72 in order to prevent dripping, according to the amount of liquid material stored in the sump pipe 76. When the water head of the liquid material stored in the sump pipe 76 reaches the height of the end of the negative pressure adjustment pipe 49, the effect of the negative pressure adjustment pipe 49 is lost. Therefore, the liquid material in the sump pipe 76 is discharged from the discharge channel 73 before that happens.

[0061] The length of the negative pressure adjustment pipe 49 is, for example, 1 / 3 or more of the length of the relief pipe 76, preferably 1 / 2 or more. The negative pressure adjustment pipe 49 in Example 2 has the same diameter as the relief passage 72. Preferably, the liquid material is filled up to the end of the negative pressure adjustment pipe 49 in the waiting pipe 76 before the discharge operation is performed. This is because by keeping the lower end position (the tip of the discharge port 33) and the upper end position (the end of the negative pressure adjustment pipe 49) of the flow path filled with liquid material constant, the pressure at the discharge port 33 can be kept constant.

[0062] The discharge device of Example 2 achieves good responsiveness similar to that of Example 1, while also providing the advantageous effect of simplifying the pressure adjustment necessary to prevent dripping. The negative pressure adjustment pipe 49 of Example 2 can also be applied to other examples.

[0063] Figure 11 is a cross-sectional side view of the main part illustrating the liquid material dispensing device 20 according to Embodiment 3. In the following, the configurations common to Embodiment 2 will not be described, and the different configurations will be described in detail. The configuration of the liquid transfer unit (liquid valve section 50, pressurizing section 60, and negative pressure section 70) in Example 3 is the same as in Example 2. The discharge unit 30 in Example 3 differs from that in Example 2 in the shape of the thrust-applying member (rod) and the liquid chamber. The discharge device 20 of Example 3 has a rotary positive displacement single-screw eccentric pump mechanism and is used for discharging high-viscosity fluids or fluids mixed with solids containing powders or particles. This single-screw eccentric pump mechanism is configured such that a male screw rotor 131 is fitted into a female screw stator inner bore 132. From another perspective, the male screw rotor 131 acts as a thrust-generating member, and the female screw stator inner bore 132 becomes a liquid chamber that communicates with the discharge port 33.

[0064] The male screw-type rotor 131 is formed, for example, in the shape of a single male screw, has a longitudinal cross-sectional shape that is approximately circular, and the pitch of the helical shape is set to 1 / 2 the pitch of the stator bore 132. When this rotor 131 rotates in a predetermined direction, the liquid material present in the space between the rotor 131 and the stator bore 132 is transferred and discharged from the discharge port 33. At this time, the rotor 131 performs eccentric rotational motion, rotating on its own axis while revolving around the central axis of the stator bore 132. The upper end of the rotor 131 is connected to a rotor drive mechanism (not shown) that causes the rotor 131 to perform eccentric rotational motion.

[0065] The discharge device 20 of Example 3 has the problem that when it is in standby mode for discharge, the communication between the stator bore 132 and the discharge port 33 is not blocked, so liquid dripping occurs from the discharge port 33. For this reason, it is necessary to quickly release the residual pressure in the stator bore 132 and apply negative pressure to the stator bore 132 when it is in standby mode for discharge. In this regard, the discharge device 20 of Embodiment 3 is equipped with a liquid transport unit similar to that of Embodiment 2. Therefore, by connecting the stator inner bore 132 and the negative pressure section 70 with the switching valve 51 when discharge is completed, the residual pressure in the stator inner bore 132 can be quickly released, and the problem of liquid dripping can be resolved. Furthermore, it is also possible to implement a configuration in which the negative pressure applied to the retraction channel is high immediately after discharge is completed, and the negative pressure applied to the retraction channel is relatively low when discharge is in standby mode.

[0066] The discharge device 20 of Embodiment 3 described above has extremely good responsiveness because the pressurization and depressurization of the stator bore 132 is performed via an incompressible liquid material. Furthermore, since it is equipped with the same liquid transfer unit as Embodiment 2, pressure adjustment necessary to prevent dripping is simple.

[0067] Figure 12 is a cross-sectional side view of the main part illustrating the liquid material dispensing device 20 according to Embodiment 4. In the following, the configurations common to Embodiments 2 and 3 will not be described, and the different configurations will be described in detail. The configuration of the liquid transfer unit (liquid valve section 50, pressurizing section 60, and negative pressure section 70) in Example 4 is the same as in Examples 2 and 3. The discharge unit 30 of Example 4 is a known jet-type discharge device in which a rod 31 reciprocates at high speed, and the forward movement of the rod 31 causes liquid material to be discharged in droplet form from the discharge port 33. In this discharge unit 30, when the discharge is in standby mode, the tip of the rod 31 does not rest on the bottom surface of the liquid chamber 32, so that communication between the discharge port 33 and the liquid chamber 32 is maintained even when the discharge operation is in standby mode. Therefore, although liquid dripping may occur from the discharge port 33 when the discharge operation is in standby mode, the liquid transport unit, which has the same configuration as in Examples 2 and 3, prevents the occurrence of liquid dripping. During discharge operation, the tip of the rod 31 may rest on the bottom surface of the liquid chamber 32 or it may not rest on the bottom surface of the liquid chamber 32.

[0068] A piston chamber (not shown) is provided at the top of the discharge unit body 36, and a piston provided at the top of the rod 31 slides within the piston chamber. This piston chamber is in communication with a switching valve 39, and the rod 31 reciprocates when pressurized air is supplied to the piston chamber or when air is discharged from the piston chamber via the switching valve 39.

[0069] In the discharge device of Example 4, which is equipped with the same liquid transfer unit as in Examples 2 and 3, it is possible to achieve good responsiveness while also realizing the advantageous effect of simplifying the pressure adjustment necessary to prevent dripping.

[0070] <Structure> Figure 13 is an overall configuration diagram of the liquid material dispensing device 20 according to Example 5. The discharge unit 30 is a known jet-type discharge device or a known screw-type discharge device. Inside the discharge unit body 36, there is a liquid chamber 32 that is in fluid communication with the discharge port 33 and the internal flow path of the switching valve 51. The switching valve 51 is disposed on the side of the discharge unit body 36 and is fluidly connected to the liquid chamber 32, the pressurized flow path 62 and the retracted flow path 72.

[0071] As shown in Figure 13, a pressurized section opening / closing valve 101 is provided upstream of the storage container 12, a discharge channel opening / closing valve 102 is provided in the discharge channel 73 which communicates with the sill pipe 76, and a negative pressure section switching valve 78 which switches the gas flow path is provided upstream of the sill pipe 76. The switching valve 51 which switches the liquid flow path has a first position which connects the storage container 12 and the liquid chamber 32, and a second position which connects the sill pipe 76 and the liquid chamber 32. The pressurized section opening / closing valve 101, the discharge channel opening / closing valve 102, the switching valve 51, and the negative pressure section switching valve 78 open and close based on commands from the control unit 99. Alternatively, the pressurized section on / off valve 101 may be installed between the storage container 12 and the switching valve 51, rather than upstream of the storage container 12. In other words, the pressurized section on / off valve 101 may be installed in the pressurized flow path 62 and controlled to connect or disconnect the storage container 12 and the switching valve 51.

[0072] The pressurizing valve 101 is provided on the pipe A16 that supplies air adjusted to a desired pressure to the storage container 12, and connects or disconnects the air supply source 111 and the storage container 12. That is, the pressurizing valve 101 has an open position that connects the air supply source 111 and the storage container 12 and a closed position that disconnects them. The discharge channel opening / closing valve 102 is installed in the discharge channel 73 and functions as a discharge channel opening / closing mechanism that connects or blocks the refrigeration pipe 76 to the outside world. That is, the discharge channel opening / closing valve 102 has an open position that connects the discharge channel 73 to the outside world and a closed position that blocks it from the outside world.

[0073] The negative pressure switching valve 78 is connected to pipe G97 which communicates with the pressurizing source 112 and pipe H98 which communicates with the negative pressure source 113, and selectively switches communication with pipe D77 (and the relief pipe 76). That is, the negative pressure switching valve 78 has a pressurizing position in which pipe G97 and the relief pipe 76 communicate, and a depressurizing position in which pipe H98 and the relief pipe 76 communicate. The air supply source 111 and the pressurization source 112 supply pressurized air adjusted to the desired pressure, and the negative pressure source 113 applies an intake pressure to the inside of the pipe H98 to the desired negative pressure.

[0074] <Discharge operation> (during discharge) The process begins with the liquid material 25 supplied from the storage container 12 filling the container through the pressurized channel 62, the switching valve 51, and the liquid chamber 32 to the discharge port 33. The control unit 99 sets the pressurizing valve 101 to the open position and simultaneously sets the switching valve 51 to the first position, which connects the pressurizing passage 62 and the liquid chamber 32. Almost simultaneously, the control unit 99 operates the rod 31, causing the liquid material in the liquid chamber 32 to be discharged from the discharge port 33.

[0075] (When dispensing ends) The control unit 99 stops the operation of the rod 31, sets the switching valve unit 51 to the second position which connects the retraction passage 72 and the liquid chamber 32, and sets the negative pressure switching valve 78 to the reduced pressure position. As a result, the pressure remaining in the liquid chamber 32 is released toward the retraction passage 72 which is regulated to negative pressure, and the discharge of liquid material from the discharge port is quickly terminated.

[0076] <Liquid material discharge operation> This section describes the operation of discharging the liquid material accumulated in the refrigeration pipe 76 to the outside. The control unit 99 closes the pressurizing valve 101 and sets the switching valve 51 to the first position, which connects the storage container 12 and the liquid chamber 32. As a result, the storage container 12 and the liquid chamber 32 are in communication, but because the pressurizing valve 101 is closed, the liquid material in the storage container 12 is not pressurized, and the risk of liquid material leaking from the discharge port 33 is minimized. In addition, when the switching valve 51 is in the first position, the communication between the negative pressure pipe 76 and the liquid chamber 32 is blocked by the switching valve 51.

[0077] The control unit 99 sets the negative pressure switching valve 78 to a pressurized position that connects pipe G97 and pipe D77. As a result, the inside of the refrigeration pipe 76 changes from a negative pressure environment to a pressurized environment. Next, the control unit 99 switches the discharge channel opening / closing valve 102 to the open position. As a result, the liquid material in the sill pipe 76 is discharged to the outside through the discharge channel opening / closing valve 102. When the switching valve 51 is in the first position, the communication between the sill channel 72 and the liquid chamber 32 is blocked, so the liquid material in the sill pipe 76 does not flow into the liquid chamber 32 via the sill channel 72.

[0078] According to the liquid material dispensing device of Embodiment 5 described above, the opening and closing and switching of each valve can be performed automatically based on the command of the control unit 99, so that the periodic disposal of the liquid material in the sill pipe 76 can be automated.

[0079] The present invention is applicable to liquid material dispensing devices of various dispensing methods. Examples of dispensing methods in which the liquid material comes into contact with the workpiece before it separates from the dispensing part include the tubing type, which has a flat tubing mechanism or a rotary tubing mechanism; the plunger type, which dispenses liquid material by moving a plunger that slides in close contact with the inner surface of a storage container with a nozzle at its tip by a desired amount; the screw type, which dispenses liquid material by the rotation of a screw; and the valve type, which controls the dispensing of liquid material to which a desired pressure has been applied by opening and closing a valve.

[0080] Examples of discharge methods in which the liquid material contacts the workpiece after it has moved away from the discharge section include a jet type in which a valve body collides with a valve seat to eject the liquid material from the nozzle tip, a plunger jet type in which a plunger is moved and then stopped abruptly to eject the liquid material from the nozzle tip, and a continuous jet or demand inkjet type.

[0081] 1: Main body, 2: Screw through hole, 3: Flow path, 4: Inlet, 5: Housing, 6: Nozzle, 7: Screw, 8: Rod, 9: Motor, 10: Liquid material dispensing device, 11: Mounting port, 12: Storage container, 13: Control unit, 14: Adapter, 15: Seal member, 16: Pipe A, 17: Pipe B, 18: Pipe C, 20: Liquid material dispensing device, 25: Liquid material, 30: Dispensing unit, 31: Rod, 32: Liquid Chamber, 33: Discharge port, 34: Liquid supply port, 35: Nozzle, 36: Discharge unit body, 37: Rod drive source, 38: Liquid chamber bottom opening, 39: Switching valve, 40: Liquid supply unit, 45: Opening, 47: Plug, 48: Discharge member, 49: Negative pressure adjustment pipe, 50: Liquid valve section, 51: Switching valve, 52: Valve block, 53: Liquid material supply port, 54: Liquid material opening, 55: Valve body, 56: Diaphragm, 57: Dial Ramro Rod A, 58: Dial Ram Rod B, 59: Connecting part, 60: Pressurizing part, 61: Liquid transfer block A, 62: Pressurized passage, 70: Negative pressure part, 71: Liquid transfer block B, 72: Relief passage, 73: Discharge passage, 74: End opening, 76: Relief pipe, 77: Pipe D, 78: Switching valve, 81: Passage A, 82: Passage B, 83: Passage C, 84: Switching passage, 91: Liquid transfer block C, 94: Tank, 95: Pipe E, 96: Pipe F, 97: Pipe G, 98: Pipe H, 99: Control unit, 101: Pressurization valve, 102: Discharge channel valve, 111: Air supply source, 112: Pressurization source, 113: Negative pressure source, 131: Rotor, 132: Stator bore, 151: Switching valve, 155: Valve body, 201: Coating device, 202: Stand, 203: Measurement unit, 204: Holding unit, 205: Relative drive unit, 206: Coating target object, 207: Table, 209: Adjustment table