JP2936691B2 - valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The valve of the present invention will be described in detail according to the following items.

A. Industrial application fields B. Summary of the invention C. Prior art [Fig. 5] D. Problems to be solved by the invention [Fig. 5] E. Means for solving the problems F. Examples [Fig. 1 and 2] a. Valve body b. Pressure control means, flow rate control c. Stopper G. Usage example [Figs. 3 and 4] a. Outline of fine powder injection device [Fig. 3] b. Flow control system [Fig. 4] H. Effects of the invention (A. Industrial application field) The present invention relates to a novel valve. Specifically, the valve body is provided with a tubular valve body having rubber elasticity and a closed space positioned so as to surround the outside thereof, and by supplying high-pressure air into the closed space, the valve body is changed by changing the pipe diameter of the valve body. The present invention relates to a valve for adjusting the flow rate of a fluid passing therethrough, which can increase the operating speed of the valve element when increasing the flow rate of the fluid flowing through the valve element, and the rubber elasticity of the valve element is slightly deteriorated. It is an object of the present invention to provide a novel valve that does not lower the operating speed of the valve element.

(B. Summary of the Invention) When the flow rate of the fluid passing through the valve body is increased, the valve of the present invention actively discharges the air in the closed space by the negative pressure generator, thereby flowing through the valve body. The operation speed of the valve body when increasing the flow rate of the fluid can be increased, and the operation speed of the valve body does not decrease even if the rubber elasticity of the valve body slightly deteriorates. Also, by providing a plurality of stoppers on the inner peripheral surface of the housing, the valve body is prevented from expanding more than necessary, so that the flow rate of the fluid in the fully opened state can be kept constant.

(C. Prior Art) [FIG. 5] A valve used for controlling the flow of a fluid such as a liquid or a gas or a powder or controlling the flow rate is provided with a rubber-elastic tubular valve body using high-pressure air. In such a case, the pressure of the high-pressure air is reduced, and the pressure of the high-pressure air is reduced to change the flow path in the opening direction by the elasticity of the valve body.

FIG. 5 shows an example a of a conventional valve provided with such a valve body.

In the drawing, reference numeral b denotes a housing, which comprises a cylindrical main part c and pipe joints d and d.

The pipe joints d, d are formed by integrally forming the tubular portions e, e and the flange portions f, f protruding from the outer peripheral surface thereof, and the flange portions f, f close the both ends of the main portion c. Both ends of a tubular valve body g made of a rubber material are externally fitted and fixed to ends of the tubular portions e, e of the pipe joints d, d facing each other. Thereby, the tubular portion e,
A flow path h through which fluid flows is formed by e and the valve body g, and a closed space i surrounding the valve body g from the outside is formed by the main part c and the flange parts f and f. A high-pressure air supply pipe extending from an air compressor (not shown) is connected to the closed space i.

Thus, when high-pressure air is supplied into the closed space i to increase the pressure in the closed space i, the pipe diameter of the valve body g is reduced, and the flow rate of the fluid flowing through the flow path h of the valve body g decreases. Then, when high-pressure air is further supplied into the closed space i, the valve body g is deformed as shown by the two-dot chain line in FIG. 5, the flow path h is closed, and the flow of the fluid is stopped. In this state, the supply of high-pressure air to the closed space i is stopped, and
When an exhaust port (not shown) is opened, the valve element g is caused to flow by the elasticity of the valve element and the pressure of the fluid flowing through the valve element g.
Is opened so that the fluid flows through the flow path h.

(D. Problems to be Solved by the Invention) [FIG. 5] This type of conventional valve a has a low operating speed, particularly when the valve g is deformed in a direction in which the flow path h opens. In addition, there is a problem that this becomes remarkable over time.

That is, in the conventional valve a, when the flow path h is opened, the supply of the high-pressure air to the closed space i is stopped, and the closed space i is opened, so that the valve body g is made elastic by its rubber elasticity. , The high-pressure air remaining in the closed space i must be discharged only by the elasticity of the valve body g. There has been a problem that it takes time and the operation speed is slow. Further, when the negative pressure is applied in the flow path of the valve element g, the situation is further increased.

In addition, the rubber elasticity of the valve body g deteriorates with time, and furthermore, the elasticity of the valve body g is remarkably reduced when elongation or cracks occur due to local stress due to repeated deformation. This has been a serious problem in devices requiring the responsiveness of valves.

(E. Means for Solving the Problems) In order to solve the above problems, the valve of the present invention includes a valve body formed of a material having rubber elasticity and a tubular shape, and the valve body is sealed around the outside of the valve body. A housing forming a space, a high-pressure air is supplied to the closed space by a positive pressure generator to change a cross-sectional area of the valve body, thereby adjusting a flow rate of a fluid passing through the valve body, and further comprising a closed space. When a negative pressure generator is connected to the space and the flow rate of the fluid is increased, the negative pressure generator discharges the compressed air in the closed space. A stopper is provided so as to prevent the valve body from becoming unnecessarily thick by blocking it even when the compressed air in the closed space is exhausted by the negative pressure generator and the valve body expands, and is stopped when it comes into contact with the stopper. It is.

Therefore, in the valve of the present invention, when the flow rate of the fluid is reduced, high-pressure air is supplied into the closed space to deform the valve body so that the pipe diameter is reduced, and when the flow rate of the fluid is increased. Since the high pressure air in the closed space is positively discharged by the negative pressure generator and the valve body is sucked from the outside and deformed in the direction in which the pipe diameter increases, especially when the flow rate of the fluid is increased, the valve body is used. Can be performed quickly,
Moreover, since the deformation in the direction of expanding the pipe diameter can be performed without relying on the rubber elasticity of the valve body, even if the rubber elasticity of the valve body deteriorates with time, the speed of the operation of expanding the pipe diameter may decrease. No.

Further, in the present invention, since the plurality of stoppers are protrudingly provided on the inner peripheral surface of the housing, even when the pressure in the closed space is reduced, the valve body comes into contact with the stopper and the pipe diameter does not expand more than necessary. . Therefore, the pipe diameter of the valve body in the fully opened state, in other words, the flow rate of the fluid can be always kept constant, and the flow rate can be controlled more stably.

(F. Embodiment) [FIGS. 1 and 2] The details of the valve of the present invention will be described below according to a first embodiment.

(A. Valve Body) The valve 1 includes a cylindrical housing and a tubular valve body disposed in the housing.

Reference numeral 2 denotes a housing, which has a cylindrical main portion 3, pipe joints 4 and 4 'attached to both ends of the main portion 3, and the pipe joints 4, 4' so as not to be detached from the main portion 3. It is composed of holding members 5, 5 'for holding.

The main part 3 is joined to its right end (the rightward direction in FIG. 1 is the right side, and the leftward direction is the left side. In the following description, this direction is used when indicating the direction). The flange 6 is formed so as to protrude outward, and an annular notch 6a is formed on the inner peripheral edge on the side where the joining flange 6 is formed. Each of the left end face of the main portion 3 and the notch 6a .. Or 8, 8,... Are formed in a circle facing left or right.
A screw hole 9a is formed substantially at the center of the peripheral wall 9 of the main part 3 in the axial direction.

The pipe joints 4 and 4 'are integrally formed with tubular portions 10, 10' having a diameter approximately half the diameter of the main portion 3 and mounting flanges 11, 11 'projecting outward from the outer peripheral surface of the tubular portions 10, 10'. The outer diameters of the mounting flanges 11 and 11 'are formed to be substantially the same as or slightly smaller than the inner diameter of the main part 3.

Also, the left-side pipe joint 4 has a relatively long tubular portion 10,
The mounting flange 11 is formed at a position slightly closer to the right side from the center in the axial direction.
The length of 0 'is half of the tubular portion 10 of the left pipe joint 4, and the mounting flange 11' is formed at the right end thereof.

, 12 ′, 12 ′,... Are bottomed screw holes formed to open leftward or rightward, respectively, at portions near the periphery of the mounting flanges 11, 11 ′. And the screw hole
, 12 ', 12', ... are arranged at equal intervals in the circumferential direction.

The holding members 5, 5 'are formed in a circular band shape having the same outer diameter as the outer diameter of the main part 3, and the inner surfaces of the holding members 5, 5' (in the case of the left holding member 5, An annular notch 13, 13 ′ is formed on the outer peripheral edge of the right measurement surface and the right holding member 5 ′ (the left side surface), whereby the holding member 5,
Thin portions 14, 14 'are formed on the outer periphery of 5'.

The inner diameter of the center hole 15 of the left holding member 5 is formed to be slightly larger than the outer diameter of the tubular portion 10 of the left fitting 4, and the inner diameter of the center hole 15 ′ of the right holding member 5 ′ is the tubular shape of the right fitting 4 ′. Part 1
It is formed substantially the same as the inside diameter of 0 '.

The cutouts 13 and 13 ′ are provided with the surface facing inward and the housing 2.
Surface inclined at an angle of approximately 45 ° to the axis of
13a, 13'a (hereinafter referred to as "seal surfaces").

The diameter of the base of the cutouts 13, 13 ′, that is, the portion where the inside of the thin portions 14, 14 ′ intersects the sealing surfaces 13 a, 13 ′ a is substantially the same as the inner diameter of the main portion 3.

, 16 ′, 16 ′,... Are holding members 5,
5 'is a screw insertion hole formed at a portion except for the thin portions 14 and 14' at circumferentially equal intervals.
, 16 ′, 16 ′,...
4 ′ mounting flanges 11, 12 ′
.., 12 ′, 12 ′,.

, 17 ′, 17 ′,... Are holding members 5,
Screw insertion holes formed in the 5 'thin portions 14, 14' at regular intervals in the circumferential direction, and the screw insertion holes 17, 17, ...
, 17 ', 17', ... respectively correspond to screw holes 7, 7, ..., 8, 8, ... formed in both end faces of the main part 3.

Then, the holding member 5 is fitted to the left fitting 4 from the left side (the side where the tubular portion 10 protrudes long from the mounting flange 11) such that the sealing surface 13a is on the mounting flange 11 side. .. And the holding member 5
Screws 18, 18,... From the left are aligned with screw insertion holes 16, 16,.
Are screwed into the screw holes 12, 12,..., Whereby the pipe joint 4 and the holding member 5 are connected.

Also, the right fitting (1)
1 '), the holding member 5' is superimposed on the mounting flange 11 'such that the sealing surface 13'a is on the mounting flange 11' side, and the screw holes 12 ', 12',.・
Are screwed from the right side with the screw insertion holes 16 ', 16',... Aligned with the screw insertion holes 16 ', 16',.・ Screw holes 12 'and 1
2 ', ..., whereby the pipe joint 4' and the holding member 5 'are connected.

The pipe joint 4 and the holding member 5 and the pipe joint 4 'and the holding member 5' which are connected in this manner have the mounting flanges 11, 11 'of the pipe joints 4, 4' from the left or right of the main part 3. 3 is inserted so as to be fitted inside, and the screw insertion holes 17 of the holding members 5, 5 '
17, ..., 17 ', 17', ... and the screw hole 7 of the main part 3,
, 8, 8, ...
19, 19, ..., 19 ', 19', ..., screw insertion holes 17,
17, ..., 17 ', 17', ..., screw holes 7,
, 8, 8, ... are respectively attached to both ends of the main part 3.

Reference numerals 20 and 20 denote O-rings, which are sealing surfaces 13a and 13'a of the holding members 5 and 5 'and holding members 5 and 11 of the mounting flanges 11 and 11'.
The screws 18 are arranged separately in annular spaces defined by the surface facing the 5 'side and the inner peripheral surface 9b of the main part 3.
18 ', 18', ... and 19, 19, ..., 19 ', 19',
Are tightly adhered to the respective surfaces forming the space, whereby the space between the inner peripheral surface 9b of the main portion 3 and the mounting flanges 5, 5 'is kept airtight.

Numeral 21 denotes a tubular valve body formed of a material rich in rubber elasticity. Both ends 21a, 21a of the tubular portion 10 of the left pipe joint 4 protrude from the mounting flange 11 to the right and the right pipe joint. Each of which is separately fitted to the 4 'tubular portion 10', and
It is fixed with an adhesive.

Thus, the tubular portions 10 and 10 'of the two pipe joints 4 and 4' are connected to each other through the valve body 21, and the outer peripheral surface of the valve body 21 and the main portion 3 are provided outside the valve body 21. Inner peripheral surface 9b and mounting flange
A cylindrical closed space 22 is formed by 11, 11 '.

The joining flange 6 of the main part 3 is for connecting a required pipe or the like forming a fluid flow path to the valve 1.

(B. Pressure control means, flow rate control) 23 is a high-pressure air supply / discharge device, which has an air supply port 23a for discharging high-pressure air and an intake port 23b for sucking air.

Reference numeral 24 denotes a supply / exhaust switching valve, and the air supply port 24a is connected to the air supply port 23a of the high-pressure air supply / discharge device 23, and the exhaust port 24b is connected to the supply port 23b of the high-pressure air supply / discharge device 23. .

Reference numeral 25 denotes a ventilation pipe, and a nipple 25a at one end thereof is screwed into a screw hole 9a formed in the main part 3 of the housing 2, and the other end is connected to a ventilation port 24c of the supply / exhaust switching valve 24.

Therefore, the supply / exhaust switching valve 24 is connected to the ventilation port 24c and the air supply port 24a.
And the high-pressure air discharged from the high-pressure air supply / discharge device 23 is supplied into the closed space 22 of the valve 1 through the supply / exhaust switching valve 24 and the ventilation pipe 25, and the closed space 22
The pressure inside is increased. The valve body 21 is crushed toward the axis by the pressure, and the pipe diameter is reduced at the center. When the pipe diameter of the valve body 21 is reduced, the flow rate of the fluid flowing through the valve body 21 is reduced. And, the valve element 21 is shown in FIG.
As shown by the dashed line, when the flow path is completely crushed, the flow rate of the fluid becomes zero, that is, the flow of the fluid is completely stopped.

Further, in this state, when the air supply / exhaust switching valve 24 is switched to communicate the ventilation port 24c and the exhaust port 24b, the closed space 22
Since the air inside is actively discharged through the ventilation pipe 25, the supply / exhaust switching valve 24 and the high-pressure air supply / discharge device 23, the enclosed space 22
The inside becomes instantaneously the same as the pressure in the valve body 21.
The pipe wall of the valve body 21 is in the original state, that is, cylindrical, and the flow rate of the fluid is increased.

When the flow rate of the fluid flowing through the valve body 21 is increased, the pressure that has previously crushed the valve body 21 is positively removed, so that the restoring operation of the valve body 21 is extremely fast. This is done regardless of the deterioration of rubber elasticity of 21.

When the flow rate of the fluid flowing through the valve body 21 is increased, the high-pressure air in the closed space 22 is positively discharged to be equal to the pressure of the valve body 21. The pressure inside 21 may be slightly negative.

(C. Stopper) 26, 26,... Are stoppers protruding from the inner peripheral surface 9b of the main part 3 of the housing 2 toward the axis thereof, and each of the stoppers 26, 26,. The size of the circle circumscribing the tip is substantially the same as the diameter of the outer peripheral surface of the valve body 21 in a state where it is not crushed.

Therefore, even if the sealed space 22 is slightly negatively-pressed and the tube wall of the valve body 21 is pulled toward the anti-axis side, the expansion of the tube diameter of the valve body 21 due to this is applied to the stoppers 26, 26,. Since the valve body 21 is blocked at the contact, the valve body 21 is prevented from being unnecessarily thick.

(G. Usage Example) [FIGS. 3 and 4] FIGS. 3 and 4 show an example of the use of the above-described valve 1 in a flow control system in a fine powder injection device.

(A. Outline of Fine Powder Injection Apparatus) [FIG. 3] Reference numeral 27 denotes a fine powder injection apparatus, which applies fine powder made of metal, inorganic material, or the like to a required workpiece, that is, an object to be processed by using the pressure of high pressure air. The spraying performs a process such as etching, polishing, or perforation of the surface of the work. The fine powder supply tank 28, a processing chamber 30 for performing the above-described processing on the work 29, an air blower 31, It comprises an air compressor 32 for supplying high-pressure air to the body supply tank 28 and the like.

The portion 33 except the bottom of the fine powder supply tank 28 is a storage chamber for storing the fine powder 34, and the fine powder 34 is supplied from the fine powder supply unit 35 into the storage chamber 33 as needed. A high-pressure air ejection recess 36 having an upper surface opened at the bottom of the storage chamber 33 is formed at the bottom of the fine powder supply tank 28, and the upper surface of the high-pressure air ejection recess 36 is closed by a sintering filter 37.
The upper end of the suction nozzle 38 protrudes from the center of the sintering filter 37 into the storage chamber 33, and the lower end of the suction nozzle 38 is opened to the negative pressure generating chamber 39 formed at the bottom of the fine powder supply tank 28. ing. 40 is an injection nozzle arranged in the processing chamber 30,
Reference numeral 41 denotes a blower pipe extending from a high-pressure air discharge port of the air compressor 32. The blower pipe 41 branches into two branch pipes 42 and 43 from the middle thereof, and one end of the branch pipe 42 has a high-pressure air ejection recess. The other end of the branch pipe 43 is connected to one end of the negative pressure generating chamber 39. 44
Is a feed pipe connecting the other end of the negative pressure generation chamber 39 and the injection nozzle 40, and 45 is a space arranged above the suction nozzle 38 in the storage chamber 33 to form a space therebetween. The forming member, 46 is a reduction pipe connected between the bottom of the collection hopper 47 disposed at the bottom of the processing chamber 30 and the storage chamber 33, and 48 connects the internal space of the space forming member 45 and the exhaust fan 31. There is an exhaust pipe.

A part of the high-pressure air discharged from the air compressor 32 flows into the high-pressure air ejection concave portion 36, and then is injected into the storage chamber 33 through the sintering filter 37, and the fine particles mainly under the space forming member 45 due to the air vibration effect. Further, another part of the high-pressure air discharged from the air compressor 32 flows through the negative pressure generating chamber 39 at a high speed, and the air flow generates a negative pressure in the suction nozzle 38. The agitated fine powder 34 is sucked by the suction nozzle 38 and taken out to the negative pressure generating chamber 39, from where it rides on high-pressure air and blows through the supply pipe 44 to eject the injection nozzle 40.
From the work 29. Then, the fine powder 34 scattered in the processing chamber 30 is returned to the storage chamber 33 through the reduction pipe 46 together with the high-pressure air ejected from the injection nozzle 40, and the high-pressure air is formed above the space forming member 45. Filter
After flowing into the space forming member 45 through 45a, the air flows into the blower 31 via the exhaust pipe 48, where the fine powder 34 is finally separated and then discharged to the outside of the blower 31.

(B. Flow control system) [FIG. 4] In the pipes through which high-pressure air or fine powder flows, such as the blower pipe 41, the branch pipes 42, 43, or the exhaust pipe 48, the valves 1, 1,. Are interposed, and the air flowing through the various pipes is controlled by adjusting the opening degree of the internal flow passages of the valves 1, 21,.... To adjust the flow rate or stop the flow.

FIG. 4 shows a control system for performing such control.

24 _1, 24 ₂ in the figure, 24 ₃ is a so-called three-way valve-type supply and exhaust changeover valve, respectively, the gas supply port 24a _1, 24a _2, 24a _3, the exhaust port 24b _1, 24b _2, 24b ₃ and vent 24c ₁ , 24c ₂ , 24c ₃ , and each supply / exhaust switching valve 24 is provided with a moving valve element 49, and by moving the moving valve element 49, the air supply port 24 a and the ventilation port 24 c
(A first position), a position where the exhaust port 24b and the vent 24c are communicated (a second position), and a position where the vent 24c is not communicated with any of the ports 24a and 24b (the first position). 3rd position) is formed separately.

The moving valve body 4 of the supply / exhaust switching valve 24 ₁ , 24 ₂ , 24 ₃
Is adapted to be moved by 9 _1, 49 _2, 49 ₃ is electromagnetic means (not shown).

The supply / exhaust switching valve 24 ₁ , 24 ₂ , 24 ₃ is 1
The two high-pressure air supply / discharge devices 23 are connected in parallel.

That is, a ventilation pipe 50 is connected to the air supply port 23a of the high-pressure air supply / discharge device 23, and the ventilation pipe 50 is branched into three on the way, and each of the branched ventilation pipes 50 ₁ , 50 ₂ , 50 ₃ each has an air supply / exhaust switching valve 24 ₁ , 24 ₂ , 24 ₃ air supply ports 24 a ₁ , 24
a ₂ and 24a ₃ are separately connected.

Further, a ventilation pipe 51 is connected to the intake port 23b of the high-pressure air supply / discharge device 23, and the ventilation pipe 51 is branched into three on the way, and each branched ventilation pipe 51 ₁ , 51 ₂ , 51 _3. each tip of supply and exhaust changeover valve 24 _1, 24 _2, 24 ₃ of the outlet 24b _1, 24
b ₂ and 24b ₃ are separately connected.

Vent 24c ₁ of the supply and exhaust changeover valve _{24 1, 24 2, 24 3} , 24c 2, 2
4c ₃ is connected to the enclosed space 22, 22, 22 of the valve 1 _1, 1 _2, 1 ₃ through the respective vent pipes 25, 25, 25 as described above.

The opening and closing operation of the valve 1 can be performed by setting the movable valve element 49 of the supply / exhaust switching valve 24 to a predetermined position.

In Figure 4, the valve 1 ₁ shown on the left is for the moving valve body 49 ₁ of the supply and exhaust changeover valve 24 ₁ was also shown in wo was in the first position to occlude it.

When the moving valve element 49 ₁ of the supply and exhaust changeover valve 24 ₁ in the first position, the supply and exhaust changeover valve 24 ₁ is passed through vents 24c ₁ and the air supply port 24a ₁ communicate with each other, the high pressure air supply and discharge device 23 air openings 23a- vent pipe 50 ₁ - the supply and exhaust changeover valve 24 ₁ air inlets 24a ₁ - vent 24c ₁
- vent pipe 25 closed space 22 ₁ a flow path is formed that is high pressure air to crush the valve body 21 ₁ enters the valve 1 ₁ of the closed space 22 ₁ and thus closing the valve 1 _1.

Further, in Figure 4, the valve 1 ₂ shown in the middle shows the one in which the moving valve member 49 and _second intake and exhaust changeover valve 24 ₂ in the second position in order to open it.

When the moving valve element 49 and _second intake and exhaust changeover valve 24 ₂ in the second position, is passed through the vent 24c ₂ of the supply and exhaust changeover valve 24 ₂ exhaust port 24b ₂ communicate with each other, the valve 1 _second closed space 22 ₂ -Vented vibe 25
- intake and exhaust switching valve 24 _{and second} vents 24c ₂ - outlet 24b ₂ - vent vibrator 51 ₂ - is the flow path of the inlet port 23b of the high pressure air supply and discharge device 23 is formed by the high pressure air valve 1 _second closed space 22 It is discharged from the ₂ to the outside from the high pressure air supply and discharge device 23 through the channel, the closed space 22 _{and second} valve 1 ₂ is the same or稍負pressure state and pressure of the valve body 21 in ₂ valve 1 ₂ Is released.

In the valve 1 ₃ shown in the right side in FIG. 4, wherein the moving valve element 49 ₃ of air supply and exhaust changeover valve 24 ₃ to maintain the state of reduced flow rate of the fluid flowing in the third position It was done.

When the moving valve element 49 ₃ of air supply and exhaust changeover valve 24 ₃ to the third position, the supply and exhaust changeover valve 24 ₃ air inlets 24a _3, also not communicated in any exhaust port 24b ₃ and vent 24c ₃ Moreover, it is blocked there. Therefore, the _third of the supply / exhaust switching valve 243
Position an appropriate pressure to the first and to position the valve 1 ₃ closed space 22 ₃ immediately before the addition of, after the fluid flowing through the valve 1 ₃ at a predetermined flow rate, a supply and exhaust changeover valve 24 ₃ 3 by the position, enclosed space of the valve 1 ₃
22 ₃ is maintained at a predetermined pressure, so that the fluid flowing through the valve 1 ₃ is maintained at a predetermined flow rate.

Further, when the air supply and exhaust changeover valve 24 ₃ to the third position, since this ventilation pipe 50 _3, 51 ₃ connected to are both closed in the part, which is connected to the high pressure air supply and discharge device 23 vent never end of the pipe 50 and 51 are opened, when performing air blowing or exhaust air to the other air supply and exhaust changeover valve 24 _1, 24 _2, nor interfere.

(H. Effect of the Invention) As is clear from the above description, the valve of the present invention has a valve body formed in a tubular shape from a material having rubber elasticity, and a closed space surrounding the outside of the valve body. And a housing to be formed, by supplying high-pressure air to the enclosed space by a positive pressure generator to change the cross-sectional area of the valve body to adjust the flow rate of the fluid passing through the valve body, and further to the enclosed space. When a negative pressure generator is connected to increase the flow rate of the fluid, a plurality of stoppers are provided inward on the inner peripheral surface of the housing in the valve configured to discharge the compressed air in the closed space by the negative pressure generator. Even if the compressed air in the closed space is exhausted by the negative pressure generator and the valve body expands, it is stopped when it comes into contact with the stopper so that the valve body does not become unnecessarily thick. And

Therefore, in the valve of the present invention, when the flow rate of the fluid is reduced, high-pressure air is supplied into the closed space to deform the valve body so that the pipe diameter is reduced, and when the flow rate of the fluid is increased. Since the high pressure air in the closed space is positively discharged by the negative pressure generator and the valve body is sucked from the outside and deformed in the direction in which the pipe diameter increases, especially when the flow rate of the fluid is increased, the valve body is used. Can be performed quickly,
Moreover, since the deformation in the direction of expanding the pipe diameter can be performed without relying on the rubber elasticity of the valve body, even if the rubber elasticity of the valve body deteriorates with time, the speed of the operation of expanding the pipe diameter may decrease. No.

Further, in the present invention, since the plurality of stoppers are protrudingly provided on the inner peripheral surface of the housing, even when the pressure in the closed space is reduced, the valve body comes into contact with the stopper and the pipe diameter does not expand more than necessary. . Therefore, the pipe diameter of the valve body in the fully opened state, in other words, the flow rate of the fluid can be always kept constant, and the flow rate can be controlled more stably.

In the above-described embodiment, the supply and exhaust of high-pressure air to and from the closed space are performed by one high-pressure air supply / discharge device connected via a supply / exhaust switching valve. You may do it.

Further, the specific shapes or structures shown in the above embodiments are only examples of the embodiment of the valve of the present invention, and these limit the technical scope of the present invention. Must not be interpreted.

[Brief description of the drawings]

FIGS. 1 and 2 show an embodiment of the valve of the present invention. FIG. 1 is a longitudinal sectional view, FIG. 2 is an exploded perspective view with a part cut away, and FIGS. Shows an example of using the valve of the present invention in a valve control system in a fine powder injection device, FIG. 3 is a schematic side view showing the entire fine powder injection device, FIG. 4 is a conceptual diagram showing a valve control system,
FIG. 5 is a longitudinal sectional view showing an example of a conventional valve. DESCRIPTION OF SYMBOLS 1 ... Valve 2 ... Housing 9b ... Inner peripheral surface 21 ...
... Valve, 22 ... Closed space, 23 ... Positive pressure generator, 23 ... Negative pressure generator, 26 ... Stopper

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16K 7/00-7/20

Claims (1)

(57) [Claims] A valve body formed in a tubular shape from a material having rubber elasticity; and a housing surrounding the outside of the valve body to form a closed space, and a high-pressure air is generated in the closed space by a positive pressure generator. By changing the cross-sectional area of the valve body by supplying the valve body, the flow rate of the fluid passing through the valve body is adjusted, and a negative pressure generator is connected to the closed space. In the valve configured to discharge the compressed air in the closed space by the negative pressure generator, a plurality of stoppers are protruded inward on the inner peripheral surface of the housing, and the compression in the closed space is performed by the negative pressure generator. A valve, wherein even if the air is discharged and the valve body expands, the valve body is prevented from contacting with the stopper so that the valve body does not become unnecessarily thick.