JPH0448854Y2 - - Google Patents

Description

[Detailed explanation of the idea]

INDUSTRIAL APPLICATION FIELD The present invention relates to a discharge device with a variable discharge flow rate, and more particularly, it is suitable for use in connection with a sealing gun for applying adhesives, sealants, etc. by an industrial robot, for example. The present invention relates to a variable discharge flow rate discharge device that can be implemented. Prior Art A typical prior art is shown in FIG.
The main body 1 of the sealing gun is formed with a nozzle 2 through which adhesive or sealant is discharged, and a valve body 5 can be seated on a valve seat 4 of a valve chamber 3 provided in the main body 1. . A piston 8 housed in a cylinder chamber 7 is connected to a valve rod 6 connected to the valve body 5 , and a spring 9 causes the valve body 5 to move against the valve seat 4 .
is biased in the direction of seating. A coating agent such as an adhesive or a sealant is pumped into the valve chamber 3 from a pump 10 through a conduit 11. Air pressure is supplied to the cylinder chamber 7 via an electromagnetic switching valve 12 . When such a main body 1 is attached to the working end of an industrial robot and a coating agent is applied,
When the coating path has a corner, that is, an intersection between two straight lines, or when a sudden change in the posture of the working end is required, the speed along the coating path changes due to the characteristics of industrial robots. In the prior art shown in FIG. 4, when the piston 8 is in contact with the contact portion 13 while air pressure is being fed to the cylinder chamber 7 via the electromagnetic switching valve 12, the coating agent is discharged from the nozzle 2. It remains supplied at a constant flow rate. Therefore, as the speed of the working end decreases, the amount of coating agent applied per unit length of the coating path, and therefore its width, increases. Therefore, when the speed of the working end decreases, it is desired that the flow rate of the coating agent discharged from the nozzle 2 decreases, thereby making the width over which the coating agent is applied uniform. To solve this problem, it may be considered to vary the flow rate of the coating agent by the pump 10 depending on the speed of the working end. At this time, the viscosity of the coating agent is high, and the compressibility of the coating agent makes it dependent on the length of the pipe line 11, so the response time until a change in the supply amount of the pump 10 appears as a change in the discharge amount of the nozzle 2. There will be a delay. Another prior art that solves this problem is No. 5
As shown in the figure. In this prior art, compressed air is supplied to one chamber 7a through a variable secondary pressure reducing valve 14, and compressed air that is not depressurized is supplied to the rod side chamber 7b. In this way, the secondary pressure of the pressure reducing valve 14 is changed to stop the piston 8 and therefore the valve body 5 at a desired position. In the prior art shown in FIG. 5, the piston 8 is accurately stopped at a desired position depending on the pressure of the coating agent in the valve chamber 3 and the frictional force between the valve stem 6 and the piston 8. This requires complicated control and is not practical. Problems to be Solved by the Invention An object of the present invention is to provide a discharge device that can accurately adjust the discharge flow rate, has a simplified configuration, and has a variable discharge flow rate. Means for Solving the Problems The present invention provides a valve hole 47, a valve chamber 23 in which a valve seat 24 connected to the valve hole 47 is formed, a first cylinder chamber 27 that is partitioned from the valve chamber 23, and a first cylinder chamber 27 that is partitioned from the valve chamber 23. A second cylinder chamber 31 that is connected to the first cylinder chamber 27 and has a larger diameter than the first cylinder chamber 27; and a spring chamber 3 that is connected to the second cylinder chamber 31 and has a smaller diameter than the second cylinder chamber 31.
6 is formed with respective axes on a straight line in this order; a main body 21 having axes on the straight line within the main body 21 and extending from the valve chamber 23 to the first cylinder chamber 27; It has a valve body 25 for seating on the valve seat 24.
4, a valve rod 26 is displaceable such that the valve body 25 is seated and can be separated; a first piston 28 is housed in a first cylinder chamber 27 and fixed to the valve rod 26; The second piston 32 is housed and has a pressing part 33 that protrudes into the first cylinder chamber 27, and the pressing part 33 has a smaller diameter than the inner diameter of the first cylinder chamber 27.
2, a first compression spring 35 interposed between the first piston 28 and the pressing part 33, and a second compression spring 37 interposed between the second piston 32 and the bottom 59 of the spring chamber 36. The main body 21 is formed with a first port 38 facing the first cylinder chamber 27 and closer to the valve chamber 23, a second port 40 closer to the second cylinder chamber 31, and a second port 40 facing the spring chamber 36. 3 ports 41 are formed,
Furthermore, means 29, 30 for supplying fluid to the valve chamber 23, a working fluid pressure source 42, and electromagnetic switching valve means 43, 44, comprising: (a) a first port 38 set to atmospheric pressure; 40 is supplied with working fluid from the working fluid pressure source 42, and the third port 41 is supplied with working fluid from the working fluid pressure source 42, or the third port 41 is set to atmospheric pressure, whereby the valve body 25 is Seated on the valve seat 24, the second piston 32 is connected to the first cylinder chamber 27 and the second cylinder chamber 3.
(b) Supplying working fluid from a working fluid pressure source 42 to the first port 38 and setting the second port 40 to atmospheric pressure. (b1) The working fluid from the working fluid pressure source 42 is supplied to the third port 41, whereby the first piston 28 comes into contact with the pressing part 33, and the second piston 32 comes into contact with the first abutting part 33. It is in contact with part 45,
Or (b2) the third port 41 is set to atmospheric pressure, whereby the first piston 28 comes into contact with the pressing part 33, and the second piston 32 moves into the step-like position between the second cylinder chamber 31 and the spring chamber 36. This discharge device is characterized in that it includes such electromagnetic switching valve means 43 and 44 that come into contact with the second contact portion 46 and is capable of variable discharge flow rate. Effect According to the present invention, a fluid such as a coating agent is supplied to the valve chamber 23 from the supply means 29 and 30, and the working fluid pressure source 42 supplies a working fluid such as compressed air. , electromagnetic switching valve means 4
3 and 44 in three operating modes (a), (b1), and (b2), thus supplying a fluid such as a coating agent using the working fluid from a single working fluid pressure source 42.
(a) shut off, (b1) supply at a low flow rate, or (b2)
Can be supplied at large flow rates. Such a configuration is simple and does not require complex control. Embodiment FIG. 1 is a sectional view of an embodiment of the present invention.
A sealing gun main body 21 for applying fluid coating agents such as adhesives and sealants is fixed to the working end of the industrial robot. The coating agent is discharged from a nozzle 22 formed in the main body 21. A valve chamber 23 is formed in the main body 21, and a valve body 25 is seated on a valve seat 24 facing the valve chamber 23, and can be displaced to the right in FIG. 1 and separated. A valve rod 26 integrally connected to the valve body 25 is fixed to a first piston 28 provided in a first cylinder chamber 27 . Valve body 25 and valve stem 2
6 may be manufactured separately, and both may be integrally connected. A coating agent is supplied to the valve chamber 23 from a pump 29 via a conduit 30 at a constant pressure. The main body 21 also has a second cylinder chamber 31 connected to the first cylinder chamber 27, and a second piston 32 is housed in the second cylinder chamber 31. The second piston 32 is the first piston 2
It has a cylindrical pressing part 33 extending toward the 8 side. A spring chamber 34 is formed in the pressing portion 33 . Spring chamber 34
The spring 35 housed in is in contact with the first piston 28 . A spring chamber 36 connected to the second cylinder chamber 31 is formed in the main body 21, and a spring 37 is housed in the spring chamber 36. The spring 37 biases the second piston 32 in a direction in which the valve body 25 is seated close to the valve seat 24 . Spring 35, 37 is chamber 57
When the pressure is at atmospheric pressure, the valve body 25 touches the valve seat 24.
The pistons 28 and 32 are seated in the valve closed state.
It functions to determine the position of the The main body 21 is provided with a port 38 that communicates with a chamber 57 on the valve stem side of the first cylinder chamber 27, and a port 40 that communicates with one chamber 39 of the first piston 28.
A port 41 connected to the valve chamber 36 side is formed.
Compressed air from this air pressure source 42 is supplied to port 38 or 40 via a two-position electromagnetic switching valve 43, and compressed air is supplied to port 41 via a two-position electromagnetic switching valve 44. In the main body 21 , contact portions 45 and 46 that contact the second piston 32 are formed in the second cylinder chamber 31 . The electromagnetic switching valves 43 and 44 perform switching operations such that the operations shown in Table 1 are achieved.

[Table] Before the start of coating, the valve body 25 is seated on the valve seat 24, as shown in FIG. For this purpose, the solenoid valve 43 is in the valve position 43b,
Compressed air is supplied to the port 40, and the solenoid valve 4
4 is the valve position 44a, and the compressed air is supplied to the port 41. Port 38 is open to atmospheric pressure by valve position 43b. In order to control the flow rate of the coating agent discharged from the nozzle 22 to a small value, the solenoid valve 43 is set at the valve position 43a.
The solenoid valve 44 remains in the valve position 44a. Compressed air is thereby supplied to the port 38, the first piston 28 is displaced to the right in FIG. 1, and the second piston 32 is moved to the right in FIG.
It comes into contact with the pressing part 33 of. The pressure receiving area of the second piston 32 due to the compressed air from the port 41 is larger than the pressure receiving area of the compressed air coming from the port 38 of the first piston 28, so the second piston 32 abuts on the contact portion 45. In the state
The first piston 28 is maintained in contact with the pressing portion 33. In this way, the distance d1 between the valve seat 24 and the valve body 25 is a relatively small value, and therefore the valve hole 47 formed in the valve seat 24 is separated from the valve chamber 23.
The flow rate of the coating material discharged from the nozzle 22 through the nozzle 22 is small. When the speed along the coating path at the working end of the industrial robot decreases, the discharge flow rate of the coating material is controlled to be small in this way. To increase the discharge flow rate of the coating agent, set the solenoid valve 43 to the valve position 43a as shown in FIG.
The valve position of the solenoid valve 44 is switched to 44b. This brings the port 41 to atmospheric pressure. Therefore, the second piston 32 is pushed by the first piston 28 and is displaced to the right in FIG.
It is displaced to the right in FIG. 3 by d2 and comes into contact with the contact portion 46. At this time, the first piston 28 is in contact with the pressing portion 33. Therefore, the distance d3 between the valve seat 24 and the valve body 25 is a relatively large value (d3=d1+d2), and the coating agent is supplied from the valve chamber 23 to the valve hole 47 at a large flow rate.
As another embodiment of the present invention, in order to achieve the state shown in FIG. 1 in which the valve body 25 is seated on the valve seat 24, the solenoid valve 44 is set to the valve position 44a in the above embodiment. However, as valve position 44b,
The port 41 may be opened to atmospheric pressure. When this is done, the second piston 32 is in contact with the contact portion 46. To further describe the configuration, the main body 21 has a valve hole 4.
7, a valve chamber 23 in which a valve seat 24 connected to the valve hole 47 is formed, a first cylinder chamber 27 that is partitioned from the valve chamber 23 and has a larger diameter than the valve chamber 23,
A second cylinder chamber 31 that is connected to the cylinder chamber 27 and has a larger diameter than the first cylinder chamber 27 and a spring chamber 36 that is connected to the second cylinder chamber 31 and has a smaller diameter than the second cylinder chamber 31 are arranged in a straight line 58 in this order. It is formed with each axis of . As described above, the second cylinder chamber 31 has a larger diameter than the first cylinder chamber 27, so that the stepped contact portion 45 between the first cylinder chamber 27 and the second cylinder chamber 31 is formed. It is formed. Further, the spring chamber 36 has a smaller diameter than the second cylinder chamber 31 as described above, and thereby the second cylinder chamber 36 has a smaller diameter than the second cylinder chamber 31.
A stepped contact portion 46 is formed between the cylinder chamber 31 and the spring chamber 36. The valve stem 26 is connected to the main body 21
It has an axis on the straight line 58 and extends from the valve chamber 23 to the first cylinder chamber 27. This valve stem 26 has a valve body 25 for seating on the valve seat 24. Pressing portion 3 formed on second piston 32
3 protrudes into the first cylinder chamber 27, and this pressing portion 33 has a smaller diameter than the inner diameter of the first cylinder chamber 27, as is clear from FIG. Compressed air can be reliably supplied into the chamber 39 of the first cylinder chamber 27. The compression spring 35 is connected to the first piston 28 and the pressing part 3
3, and another compression spring 37 is interposed between the second piston 32 and the bottom 59 of the spring chamber 36. A port 38 formed in the main body 21 is formed near the valve chamber 23 facing the cylinder chamber 27, another port 40 is formed near the cylinder chamber 31, and yet another port 41 is formed near the cylinder chamber 31. It is formed facing the spring chamber 36. In this way, with a simple configuration, it becomes possible to switch the application flow rate of the coating material into two stages near the nozzle 22, so there is no response delay and the application process can be adjusted according to the speed of the working end of the industrial robot. It becomes possible to accurately switch and adjust the flow rate of the agent. The present invention can not only adjust the discharge flow rate of the coating agent but also the discharge flow rate of other fluids. Effects of the Invention As described above, according to the present invention, it is possible to switch the discharge flow rate to a plurality of discharge flow rates stepwise and accurately adjust it with a simple configuration, and the configuration for this purpose can be simplified. Particularly according to the invention, the first piston 28 fixed to the valve stem 26 is connected to the second piston 3
The amount of movement of the second piston 32 is limited by a pressing portion 33 formed in the first cylinder chamber 27 and the second cylinder chamber 31.
By the contact portion 45 and the second cylinder chamber 31
A step-like second abutment 46 between the spring chamber 36 and the spring chamber 36 limits the amount of movement, thus allowing the use of a working fluid, such as compressed air, from a single working fluid pressure source 42 to open the valve hole. The fluid supplied from 47 can be shut off and adjusted to a small flow rate or a large flow rate.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an embodiment of the present invention, Fig. 2 is a sectional view showing the operating state when the discharge flow rate of the coating material is set to a small value in the embodiment of Fig. 1, and Fig. 3 is the same as Fig. 1. 4 is a cross-sectional view showing the state when the discharge flow rate of the coating material is set to a large value in the embodiment shown in FIG.
The figure is a sectional view of the prior art, and FIG. 5 is a sectional view of another prior art. 21... Body, 22... Nozzle, 23... Valve chamber, 24... Valve seat, 25... Valve body, 26... Valve stem, 27... First cylinder chamber, 28... First piston, 29 ... pump, 31 ... second cylinder chamber, 32 ... second piston, 42 ... air pressure source,
48...Third piston, 55...Third cylinder chamber.

Claims (1)

[Claims for Utility Model Registration] A valve hole 47, a valve chamber 23 in which a valve seat 24 connected to the valve hole 47 is formed, a first cylinder chamber 27 separated from the valve chamber 23, and a first cylinder chamber. 27 and a second cylinder chamber 31 having a larger diameter than the first cylinder chamber 27;
A spring chamber 36 having a smaller diameter than the cylinder chamber 31 has a main body 21 formed with respective axes on a straight line in this order; It extends across one cylinder chamber 27 and has a valve body 25 for seating on the valve seat 24.
4, a valve rod 26 is displaceable such that the valve body 25 is seated and can be separated; a first piston 28 is housed in a first cylinder chamber 27 and fixed to the valve rod 26; The second piston 32 is housed and has a pressing part 33 that protrudes into the first cylinder chamber 27, and the pressing part 33 has a smaller diameter than the inner diameter of the first cylinder chamber 27.
2, a first compression spring 35 interposed between the first piston 28 and the pressing part 33, and a second compression spring 37 interposed between the second piston 32 and the bottom 59 of the spring chamber 36. The main body 21 is formed with a first port 38 facing the first cylinder chamber 27 and closer to the valve chamber 23, a second port 40 closer to the second cylinder chamber 31, and a second port 40 facing the spring chamber 36. 3 ports 41 are formed,
Furthermore, means 29, 30 for supplying fluid to the valve chamber 23, a working fluid pressure source 42, and electromagnetic switching valve means 43, 44, comprising: (a) a first port 38 set to atmospheric pressure; 40 is supplied with working fluid from the working fluid pressure source 42, and the third port 41 is supplied with working fluid from the working fluid pressure source 42, or the third port 41 is set to atmospheric pressure, whereby the valve body 25 is Seated on the valve seat 24, the second piston 32 is connected to the first cylinder chamber 27 and the second cylinder chamber 3.
(b) Supplying working fluid from a working fluid pressure source 42 to the first port 38 and setting the second port 40 to atmospheric pressure. (b1) The working fluid from the working fluid pressure source 42 is supplied to the third port 41, whereby the first piston 28 comes into contact with the pressing part 33, and the second piston 32 comes into contact with the first contacting part 33. It is in contact with part 45,
Or (b2) the third port 41 is set to atmospheric pressure, whereby the first piston 28 comes into contact with the pressing part 33, and the second piston 32 moves into the step-like position between the second cylinder chamber 31 and the spring chamber 36. A discharge device having a variable discharge flow rate, characterized in that it includes such electromagnetic switching valve means 43 and 44 that come into contact with the second contact portion 46.