JP2006198459A - Material discharge device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material discharge device in which a request to miniaturize a piston can be fulfilled by adopting a plurality of pistons, satisfactory pressure can be imparted to each of pistons by minimizing a pressure supply part and a valve opening can be opened/closed with high precision. <P>SOLUTION: The material discharge device is provided with: a piston rod 12 having a needle valve 17 for opening/closing the valve opening 18 in a syringe case 11; an upper piston 14 and a lower piston 15 which are fit to the piston rod; a pressure supply part 21 for pressurizing pistons to open the valve opening; another pressure supply part 22 for pressurizing pistons to block the valve opening; and a material supply part 20 for supplying a material into a chamber 19 in the syringe case. The piston rod is provided with first, second, third and fourth openings 45A-45D and first and second key grooves 46A, 46B which are used for imparting the fluid pressure to be supplied from the pressure supply part 21 or the pressure supply part 22 to each of pistons. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a material discharge device, and more particularly to an improvement of a material discharge device suitable for discharging a high viscosity material.

  In a device that discharges an adhesive, a sealing material, or the like, since the material to be discharged has a high viscosity, it is difficult to perform ON / OFF control of material discharge only by applying pressure by a pump. Therefore, conventionally, a configuration is adopted in which air pressure is applied to the piston, and the valve hole is opened and closed by a needle valve connected to the piston rod to perform ON / OFF control of material discharge.

  Patent Document 1 discloses a material discharge device suitable for discharging the above-described high-viscosity material. In the device described in the document 1, a piston is fixed to a piston rod connected to a needle valve, and air is selectively supplied to a chamber formed in two places above and below the piston so that the needle valve has a valve hole. It is configured to open and close.

JP-A-1-281968

By the way, with the miniaturization of the object to which the sealing material is applied, there is a demand for miniaturization of the discharge device itself attached to the coating robot. In this case, it is necessary to reduce the diameter of the piston included in the components of the discharge device.
However, in the type of device described in Patent Document 1, it is necessary to set the pressure of the pump that supplies the high-viscosity material to the discharge device to be high, so that when the piston is reduced in diameter, it is applied to the piston. Pressure is relatively low. Therefore, it is difficult to control the operation of quickly opening and closing the valve hole by the needle valve, which causes a material leakage or a variation in the amount of material applied at the start or end of material application. Invite

  In such a case, if it is configured to provide a plurality of pistons in order to back up the reduction in the diameter of the pistons, and pressure can be applied to each piston, it becomes possible to obtain a pressure that is the sum of these, resulting in high viscosity. It is possible to quickly open and close the valve hole with respect to the supply pressure of the material.

  However, when the pressure supply structure corresponding to each of the plurality of pistons is adopted, not only the number of supply units for applying pressure to each piston increases, but also the tube or piping path for supplying pressure is complicated. This causes another inconvenience.

[Object of invention]
The present invention has been devised by paying attention to such inconveniences, and its purpose is to meet the demand for downsizing each piston by employing a plurality of pistons and to supply pressure. It is an object of the present invention to provide a material discharge device that can apply sufficient pressure to each piston with a minimum supply portion, and can accurately open and close valve holes.

To achieve the above object, the present invention provides a valve rod that opens and closes a valve hole in a syringe case, a piston rod that is connected to the valve rod and that can be moved forward and backward together with the valve rod, and the piston rod. A plurality of pistons attached to a plurality of locations in the axial direction, pressure applying means for applying pressure to these pistons, and a material supply unit for supplying material into a chamber formed on the upstream side of the valve hole, In the material discharge device provided so that the material in the chamber can be discharged by opening the valve hole,
The pressure application means includes a single opening pressure supply unit that applies pressure to the piston in a direction in which the valve rod opens the valve hole, and a single pressure application unit that applies pressure to the piston in a direction in which the valve rod closes the valve hole. One occlusion pressure supply,
The piston rod includes passages that apply fluid pressures supplied from the open pressure supply unit and the closing pressure supply unit to the pistons, respectively.

  In the present invention, the piston rod includes an outer tube portion and an inner shaft portion accommodated in the outer tube portion, and the passage is formed between the outer tube portion and the inner shaft portion. It is preferable to adopt.

  In the present invention, the “high viscosity material” is used for materials having a viscosity of about 50 Pa · s to 1,000 Pa · s. Moreover, the medium which gives a pressure contains fluids, such as oil other than air.

  According to the present invention, it is possible to simultaneously apply pressure to each piston by a single open pressure supply unit and a block pressure supply unit, respectively, and the configuration can be simplified, and the diameter of the piston can be reduced. However, it is possible to control the valve hole to be opened and closed quickly.

  Further, since the passage formed in the piston is formed between the outer cylinder portion and the inner shaft portion, passage formation in the shaft-shaped piston can be performed very easily.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view of the material ejection device according to the present embodiment, and FIG. 2 (A) is a plan view. FIG. 2B is a right side view of FIG. In these drawings, the material discharge device 10 has an upper end portion attached to a robot arm (not shown), a syringe case 11 to which a nozzle is attached at the lower end portion, and a syringe case 11 disposed in the syringe case 11 along the axial direction. A piston rod 12 provided so as to be able to advance and retreat, an upper piston 14 and a lower piston 15 attached at two upper and lower positions along the axial direction of the piston rod 12, and a valve connected to the lower end of the piston rod 12 in the figure. A valve hole 18 that is opened and closed by a needle valve 17 as a rod, a material supply unit 20 that supplies a high-viscosity material into a chamber 19 provided above the valve hole 18, and the upper piston 14 and the lower piston 15 An open pressure supply unit 21 and a closing pressure supply unit 22 are provided as pressure applying means for applying pressure. To have.

  The syringe case 11 has a substantially square outer shape in plan view, and includes an upper case 11C provided on the lower case 11A via an intermediate case 11B. The lower case 11A has a nozzle attachment port 25 formed at the lower end thereof, a valve hole 18 located above the nozzle attachment port 25, and a material supply unit 20 connected to the chamber 19 on the side surface. Is formed. In the upper part of the chamber 19, a seal member 29 is arranged around the needle valve 17, and the seal member 29 is held at a fixed position by a seal presser 30 provided in the upper part.

  The intermediate case 11B is fixed in a state of being interposed between the lower case 11A by four bolts 32 inserted from the upper end corner portion of the upper case 11C. In the intermediate case 11B, a flange portion 36 is formed on the inner periphery of a substantially central portion in the vertical direction, and an upper chamber 37 is formed between the flange portion 36 and the upper case 11C. A lower chamber 40 is formed between the rod guide 39 and the rod guide 39 disposed below the flange portion 36.

  The piston rod 12 includes an outer cylinder portion 45 extending through the flange portion 36 and the rod guide 39 and an inner shaft portion 46 accommodated in the outer cylinder portion 45. The needle valve 17 is connected to the lower end portion via a cap nut 48. The outer cylinder portion 45 has an elongated bottomed cylindrical shape whose upper end is opened, and first to third openings 45A, 45B, and 45C are formed in the peripheral wall portion.

  The inner shaft portion 46 is accommodated in the outer tube portion 45 and is held by the outer tube portion 45. The inner shaft portion 46 is formed with first and second key grooves 46A and 46B along the axial direction at two positions in the circumferential direction, and the first and second key grooves 46A and 46B are formed corresponding to the upper and lower portions of the first key groove 46A. The first and second openings 45A and 45B are located, respectively, while the third opening 45C is located below the second keyway 46B. Note that the upper end of the second key groove 46B is configured to communicate with the inside of the upper chamber 37 as a fourth opening 45D. Here, the fluid pressures supplied from the open pressure supply unit 21 and the closing pressure supply unit 22 by the first to fourth openings 45A to 45D and the first and second key grooves 46A and 46B are changed to the pistons. 14 and 15 are provided.

  The upper piston 14 fixed to the piston rod 12 is disposed in the upper chamber 37 so as to be positioned above the first opening 45A and below the fourth opening 45D. . Further, a coil spring 49 is interposed between the upper piston 14 and the upper case 11C, so that the piston rod 12 and the needle valve 17 are always kept in a state of being biased downward. Further, the lower piston 15 is disposed above the second opening 45B and below the third opening 45C.

  The open pressure supply portion 21 constituting the pressure applying means is formed at one location of the flange portion 36 in the intermediate case 11C. The open pressure supply unit 21 is connected to a pump (not shown), and the air supplied to the open pressure supply unit 21 is supplied to the lower surface side of the upper piston 14 in the upper chamber 37. At the same time as applying an upward force to the upper piston 14, the lower piston 15 is supplied to the lower piston 15 through the first opening 45 </ b> A, the first keyway 46 </ b> A, and the second opening 45 </ b> B. It is designed to give ascending power.

  On the other hand, the closing pressure supply unit 22 is formed at one place on one side surface of the upper case 11C. The blocking pressure supply unit 22 is connected to a pump connected to the open pressure supply unit 21 and is provided so as to be selectively supplied with pressure via a switching valve (not shown). The air supplied to the blocking pressure supply unit 22 is supplied to the upper surface side of the upper piston 14 in the upper chamber 37, and at the same time, the fourth opening 45D, the second key groove 46B, and the third opening. It is supplied to the upper surface side of the lower piston 15 in the lower chamber 40 through the portion 45C, and thereby a downward force is applied to the upper and lower pistons 14 and 15.

  In FIG. 1, reference numeral 50 denotes a peephole formed in the lower case 11 </ b> A, and reference numeral 51 denotes a stopper shaft that restricts the ascent limit of the piston rod 12. An inversion concave portion 52 is formed at the center of the lower end of the stopper shaft 51, and the inversion concave portion 52 is arranged so that the fourth opening portion is formed even when the upper end of the piston rod 12 abuts against the lower end of the stopper shaft 51. The inner diameter is set so as not to block 45D. Further, a passage hole 54 is formed in the outer periphery of the lower end of the stopper shaft 51, and the reverse concave portion 52 and the upper chamber 37 are communicated with each other through the passage hole 54.

  Next, operation | movement of the material discharge apparatus 10 which concerns on this embodiment is demonstrated.

  Here, as shown in FIG. 1, it is assumed that the tip, that is, the lower end of the needle valve 17 is in a position where the valve hole 18 is closed, and a high-viscosity material is filled into the chamber 19 at a predetermined pressure from the material supply unit 20. It is assumed that

  In the case of discharging the material, air is introduced from the open pressure supply unit 21, and the air is supplied into the space between the lower surface side of the upper piston 14 and the flange portion 36. At the same time, air is supplied from the first opening 45A to the lower surface side of the lower piston 15 through the first key groove 46A and the second opening 45B. As a result, ascending pressure is applied to the upper piston 14 and the lower piston 15, respectively, and the needle valve 17 ascends together with the piston rod 12 that holds the pistons 14 and 15 fixed, and the valve hole 18 is opened. The high-viscosity material in the chamber 19 is discharged from the nozzle tip (not shown).

  When stopping the discharge, the pressure supply from the open pressure supply unit 21 is switched and the air is supplied from the closing pressure supply unit 22. The air supplied from the closing pressure supply unit 22 applies pressure to the upper surface of the upper piston 14 to generate a downward force, and at the same time, the second key groove 46B and the third opening from the fourth opening 45D. A pressure is applied to the upper surface of the lower piston 15 through 45C to generate a descending force. As a result, the needle valve 17 descends to close the valve hole 18, and the subsequent material discharge is stopped.

  The material discharge device 10 moves along a trajectory previously taught to an object to be coated while attached to a robot arm (not shown), thereby automatically applying a high-viscosity material such as a sealing material. It can be performed.

  Therefore, according to such an embodiment, even if the open pressure supply unit 21 and the closing pressure supply unit 22 are each single, the first to fourth openings 45A to 45D, the first and second With the key grooves 46A and 46B, it is possible to simultaneously apply an upward pressure and a downward pressure to the upper piston 14 and the lower piston 15, so that even if the upper piston 14 and the lower piston 15 are reduced in diameter, a pressure shortage occurs. Can be avoided, and the opening and closing of the valve hole 18 by the needle valve 17 can be performed quickly.

Although the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, the present invention is not limited to this.
That is, the invention has been illustrated and described with particular reference to certain specific embodiments, but the embodiments described above are within the scope of the technical idea and scope of the invention. On the other hand, those skilled in the art can make various modifications in shape, material, quantity, and other detailed configurations.
Accordingly, the description limited to the shape disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which excluded the limitation of all or part is included in this invention.

  For example, in the above embodiment, the case where two of the upper piston 14 and the lower piston 15 are used is shown and described, but the number of pistons can be further increased. In this case, it is sufficient to add openings in the piston rod 12 located above and below the increased piston. By configuring in this way, it is possible to effectively avoid pressure shortage when a piston having a smaller diameter is employed.

  Moreover, although the case where the piston rod 12 was comprised by the outer cylinder part 45 and the inner side shaft part 46 was shown in the said embodiment, it is also possible to form an opening part and a groove | channel using the piston rod of a single axis structure. It is. However, if the configuration of the above-described embodiment is adopted, it is possible to obtain the convenience in manufacturing the piston rod.

It is a whole structure of the material discharge apparatus which concerns on this embodiment, Comprising: Sectional drawing which follows the AA line in FIG. 2 (A). (A) is a top view of the said material discharge apparatus. (B) is the right side view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Material discharge apparatus 11 Syringe case 12 Piston rod 20 Material supply part 21 Opening pressure supply part (pressure provision means)
22 Blocking pressure supply part (pressure applying means)
45 outer cylinder portion 46 inner shaft portion 45A first opening (passage)
45B second opening (passage)
45C third opening (passage)
45D 4th opening (passage)
46A First keyway (passage)
46B Second keyway (passage)

Claims (2)

A valve rod that opens and closes a valve hole in the syringe case, a piston rod that is connected to the valve rod and that can be moved forward and backward together with the valve rod, and a plurality of piston rods that are attached to a plurality of locations in the axial direction of the piston rod A piston, a pressure applying means for applying pressure to the pistons, and a material supply unit for supplying a material into a chamber formed on the upstream side of the valve hole, and by opening the valve hole, In the material discharge device provided so that the material can be discharged,
The pressure application means includes a single opening pressure supply unit that applies pressure to the piston in a direction in which the valve rod opens the valve hole, and a single pressure application unit that applies pressure to the piston in a direction in which the valve rod closes the valve hole. One occlusion pressure supply,
The material discharge apparatus according to claim 1, wherein the piston rod is configured to include passages that respectively apply fluid pressures supplied from the open pressure supply unit and the closing pressure supply unit to the pistons. The piston rod includes an outer tube portion and an inner shaft portion accommodated in the outer tube portion, and the passage is formed between the outer tube portion and the inner shaft portion. Item 2. The material discharge device according to Item 1.

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