JPH0232872Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention supplies air pressure into the pump driving cylinder to displace the pump driving piston, and along with the movement of the pump driving piston, the piston is moved via the pump driving rod. The present invention relates to a pump device that reciprocates a pump-side piston within a pump-side cylinder.

Prior Art The present applicant previously published Utility Application No. 59-39564 with a device named ``Pump Device'', which supplies air pressure to the cylinder on the pump driving side to displace the piston, and as the piston moves, the pump is driven. A pump device has been proposed which is configured to reciprocate a piston in a pump-side cylinder via a piston rod.

Problems that the invention aims to solve However, in the above pump device, grease was applied to the inner peripheral surface of the cylinder on the pump drive side for lubrication to make the movement of the piston smooth.
As the piston reciprocates, the outer circumferential edge of the piston slides on the inner circumferential surface of the cylinder, forming a ball of grease, which is blown into the pump drive rod as air pressure is supplied. Ta. However, due to the lack of installation space due to the structure, an exhaust air filter could not be installed, and there was a problem in that grease was discharged to the outside from the exhaust port of the rod and scattered around. Furthermore, there was a problem in that exhaust noise was generated during switching by the switching valve due to the reciprocating displacement of the piston.

Therefore, an object of the present invention is to provide a pump device that solves the above problems.

Means and Effects for Solving Problems The present invention divides the inside of the pump drive side cylinder, which is supplied with air pressure as a pump drive source, into an upper chamber and a lower chamber, and the air pressure is transferred from the lower chamber to the upper chamber. A pump driving side piston having an intake passage for supplying air pressure and an exhaust passage for discharging air pressure from an upper chamber, a switching valve that alternately closes the intake passage and the exhaust passage, and a hollow part inside that communicates with the exhaust passage. one side is provided with the pump drive side piston and the other side is provided with a pump side piston that reciprocates within the pump side cylinder, and an exhaust passage is provided between the pump drive side piston and the pump side piston via a hollow part. a pump driving rod having an exhaust hole communicating with the atmosphere, a wall portion provided between the exhaust passage and the exhaust hole and defining a hollow portion of the rod into an upper space and a lower space; established,
It consists of a cylindrical body with one end opening into the upper space, the other end extending to at least a position where an exhaust hole is provided, communicating with the lower space, and having a passage area smaller than the passage area of the hollow part, and the pump drive side Grease balls generated as the piston reciprocates are allowed to pass through the wall or cylindrical body of the rod and adhere to the bottom of the rod, and the inside of the rod has a noise-muffling structure.

Embodiment The figure shows an embodiment of the pump device according to the present invention. In the figure, 1 is the air motor main body, and pneumatic piping 2
It has a pneumatic supply port 3 connected to the pneumatic pressure supply port 3, and is supplied with pneumatic pressure as a driving source through the pneumatic piping 2.
4 is an air cylinder (pump drive side cylinder),
The lower side is screwed into the air motor main body 1, and the upper opening is closed with a cap 5. Reference numeral 6 denotes a rubber air piston (pump driving side piston), which has a central exhaust passage 6a and a plurality of intake passages 6b on the outside of the exhaust passage 6a. The inside of the air cylinder 4 is defined into an upper chamber 4b and a lower chamber 4c by slidingly contacting the inner circumferential surface 4a. The inner circumferential surface 4a of the air cylinder 4 is sufficiently coated with grease, and when the air piston 6 is displaced in the directions of arrows _X1 and _X2 , as will be described later, the circumferential edge 6c slides on the inner circumferential surface 4a. can be smoothly displaced. Valve seats 6d and 6e protrude annularly from the peripheries of the exhaust passage 6a and the intake passage 6b. Moreover, the air piston 6 is attached so as to cover the flange portion 7a of the attachment member 7 by both sides. A small hole 7b corresponding to the intake passage 6b of the air piston 6 is bored in the flange 7a of the mounting member 7, and the intake passage 6b communicates the upper chamber 4b and the lower chamber 4c via the small hole 7b. ing.

Reference numeral 8 designates a switching valve, which includes an annular lower valve body 9 that contacts the valve seat 6e from the lower chamber 4c side and closes the intake passage 6b, and an annular lower valve body 9 that contacts the valve seat 6d from the upper chamber 4b side and closes the exhaust passage. an upper valve body 10 having a spherical protruding seating surface 10a that closes the valve 6a; and a plurality of connecting pins 1 that are inserted into the intake passage 6b and connect the valve bodies 9 and 10.
1 and more. The connecting pin 11 has a smaller diameter than the intake passage 6b and is slightly longer than the length of the intake passage 6b. Therefore, when one of the exhaust passage 6a and intake passage 6b of the air piston 6 is closed, the switching valve 8 opens the other. Close the valves alternately.

Reference numeral 12 denotes a pump drive rod, which has a hollow cylindrical shape with a hollow part formed inside that communicates with the exhaust passage 6a, and has an exhaust hole 13 opened to the atmosphere in the central part 12a that protrudes from the air motor main body 1. have A mounting member 7 is screwed onto the upper end of the rod 12, and the air piston 6 is attached to the rod 1 by the mounting bracket 7.
It is attached to 2. The outer periphery of the rod 12 and the air motor main body 1 are hermetically sealed by an O-ring 4, so that no air pressure leaks from the outer periphery of the rod 12. Reference numeral 15 denotes a coil spring on the upper chamber side, which is locked inside the cap 5 so as to face the upper valve body 9, and comes into contact with the upper valve body 9 as described later when the air piston 6 moves upward. Reference numeral 16 denotes a coil spring on the lower side of the room, which is wound around the outer periphery of the rod 12 and is fixed to the air motor main body 1 facing the lower valve element 10. When the air piston 6 moves downward, the coil spring 16 is attached to the lower valve element 10. come into contact with A regulator 17 is disposed in the middle of the pneumatic piping 2 and controls the pneumatic pressure supplied to the air motor main body 1 to a predetermined pressure.

Reference numeral 18 denotes a pump body, which has a discharge port 18a for discharging fluid, and is integrally connected to the air motor body 1 via a connecting portion 19. Reference numeral 20 denotes a pump side cylinder, the upper side of which is screwed into the pump body 18, and the foot valve 21 attached to the lower side.
The foot valve 21 connects the fluid flow path 21a to the check valve chamber 21.
The valve is closed by the pole 22 in b, and functions as a check valve. Reference numeral 23 denotes a ball stopper, which has a rod shape, for example, and is suspended horizontally at the upper opening of the check valve chamber 21b, and prevents the pawl 22 from coming off from the check valve chamber 21b. A pipe 25 from the tank 24 is connected to the flow path 21a, and the fluid in the tank 24 flows into the cylinder 20 through the pipe 25 and the flow path 21a, pushing up the ball 22.

26 is a piston on the pump side, which has a center hole 26a and a plurality of flow paths 26b outside the center hole 26a, and has an outer circumferential edge 26c that slides on the inner circumferential surface of the cylinder 20 to move the inside of the cylinder 20 upward. It is divided into a chamber 20a and a lower chamber 10b. Further, the piston 26 is inserted into the shaft portion 12b at the lower end of the rod 12 through a center hole 26a, and is mounted so as to be freely displaceable in the directions of arrows X ₁ and X ₂ . 27 is a valve body, which connects the flow path 26b of the piston 26.
The valve seat 26d faces the valve seat 26d, and is fixed to the lower end of the rod 12 by a nut 28. Therefore, the piston 26 is disposed between the stepped portion 12c of the rod 12 and the valve body 27 so as to be displaceable along the shaft portion 12b. 29 is a V-packet that airtightly seals between the pump body 18 and the outer periphery of the rod 12.

Reference numeral 32 denotes an extension of the main part of the present invention, which extends into the inside of the rod 12 so as to cover the exhaust hole 13 to prevent grease balls from being discharged from the exhaust hole 13 to the outside of the rod 12, as will be described later. There is. The extending portion 32 is located between a wall portion 32b provided between the exhaust passage 6a and the exhaust hole 13 and defining the hollow interior of the rod 12 into an upper space 12f and a lower space 12g, and approximately at the center of the wall portion 32b. Cylindrical body 32a provided through
It becomes more. The upper end of the cylinder 32a is the upper space 12f.
The lower end extends to a position below the position where the exhaust hole 13 is provided, and communicates with the lower space 12g. The cylindrical body 32a has a smaller diameter than the inner diameter of the rod 12a, and the passage area of the cylindrical body 32a is smaller than the passage area of the hollow portion of the rod 12.

Next, the operation of the pump device having the above structure will be explained.

Air pressure is adjusted to a predetermined pressure by a regulator 17 and is supplied into the air motor main body 1 from an air pressure supply port 3 through a pneumatic pipe 2 . Since the switching valve 8 is pressed in the direction of arrow _X1 by the air pressure supply, the lower valve element 9 closes the intake passage 6b of the piston 6, and the upper valve element 10 opens the exhaust passage 6a. For this reason,
The inside of the upper chamber 4b of the air cylinder 4 is communicated with the exhaust hole 13 and becomes atmospheric pressure, and the inside of the lower chamber 4c becomes air pressure, and this pressure difference causes the air piston 6 to exhaust the air inside the upper chamber 4b through the exhaust hole 13. While moving, move in the direction of arrow _X1 .

Note that the air piston 6 is smoothly displaced as the peripheral edge 6c slides on the inner peripheral surface 4a coated with grease.

As the air piston 6 is displaced, the air in the upper chamber 6b is guided along the spherical shape of the protruding seating surface 10a of the upper valve body 10 and smoothly flows into the exhaust passage 6b. Therefore, at the entrance of the exhaust passage 6b, the generation of eddy air flow that becomes a resistance when the air piston 6 is displaced is suppressed.

The rod 12 is displaced together with the air piston 6, and the pump-side valve body 27 is brought into contact with the valve seat 26d of the piston 26, thereby displacing the piston 26 in the direction of arrow _X1 while keeping the valve closed. Due to the displacement of the piston 26, the fluid in the upper chamber 20a of the cylinder 20 is discharged to the discharge port 1.
8a to another container 31 via piping 30, and negative pressure is generated in the lower chamber 20b, causing the ball 2
2 leaves the seat, opens the flow path 21a, and sucks the fluid in the tank 24 into the lower chamber 20b of the cylinder 20.

When the air piston 6 is further displaced in the direction of arrow _X1 , the upper valve body 10 of the switching valve 8 comes into contact with the spring 15. When the spring 15 is compressed and its resiliency becomes large, the switching valve 8 is displaced relative to the air piston 6 in the direction of arrow _X2 due to the pressing force of the spring 15. Therefore, the lower valve body 9 of the switching valve 8 is separated from the valve seat 6e to open the intake passage 6b, and the protruding seating surface 10a of the upper valve body 10 comes into contact with the valve seat 6d to open the exhaust passage 6a. Close the valve. Therefore, the air pressure in the lower chamber 4c flows into the upper chamber 4b through the intake passage 6b.

Since the pressure receiving area on the upper chamber 4b side of the air piston 6 is larger than the pressure receiving area on the lower chamber 4c side by the circular cross-sectional area of the rod 12, the air piston 6 is pressed by the air pressure in the upper chamber 4b and moves in the opposite direction of the arrow X. Displaces in _two directions. The air piston 6 is displaced in the direction of arrow _X2 while allowing air in the lower chamber 4c to flow into the upper chamber 4b from the intake passage 6b with the exhaust passage 6a closed.

As the air piston 6 returns in the direction of arrow _X2 ,
The pump-side valve body 27 is unseated to open the flow path 26b, and the piston 26 is pressed by the stepped portion 12c of the rod 12 and displaced in the direction of arrow _X2 . piston 2
6, the ball 22 of the foot valve 21 closes the flow path 21a, and the lower chamber 20b of the cylinder 20
The fluid filled in the upper chamber 2 passes through the flow path 26b.
Let it flow into 0a. Further, as the piston 26 moves downward, the rod 12 is inserted into the cylinder 20 from the outside of the pump body 18, and a volume of fluid corresponding to the cross-sectional area of the inserted rod 12 is transferred to the discharge port 1.
The liquid is fed under pressure to the container 31 from 8a.

When the air piston 6 is displaced downward in the direction of arrow _X2 , the lower chamber side valve body 9 of the switching valve 8 comes into contact with the spring 16. When the spring 16 is compressed and the elastic force increases,
The switching valve 8 is displaced in the direction of arrow _X1 with respect to the air piston 6 by the pressing force of the spring 16. For this reason,
The upper valve element 10 of the switching valve 8 moves away from the valve seat 6d to open the exhaust passage 6a, and the lower valve element 9 contacts the valve seat 6e to close the intake passage 6b. Therefore, the air pressure in the upper chamber 4b is discharged from the exhaust hole 13 of the rod 12 through the exhaust passage 6a, and the air pressure in the upper chamber 4b is discharged from the exhaust hole 13 of the rod 12.
There is atmospheric pressure inside.

In this way, the upper chamber 4b in the air cylinder 4
A pressure difference is created between the air piston 6 and the lower chamber 4c, and the air piston 6 is again displaced upward in the direction of arrow _X1 . tank 2
The fluid in the air piston 4 is continuously pumped into the container 31 by the reciprocating movement of the piston 26, which is integrally displaced with the air piston 6.

As the air piston 6 slides on the inner peripheral surface a of the air cylinder 4 and reciprocates in the directions of arrows X ₁ and X ₂ as described above, the peripheral edge 6 of the air piston 6
c gradually gathers the grease applied to the inner circumferential surface 4a to form a grease ball.

This grease ball is then vigorously blown away by the air pressure and passes through the exhaust passage 6a and intake passage 6b of the air piston 6 by the upper chamber 4b and lower chamber 4c of the air cylinder 4, and reaches the inside of the rod 12.

However, the grease balls that entered the upper space 12f of the rod 12 from the exhaust passage 6a are
The wall portion 32b of the extension portion 32 is blown away in the X ₂ direction.
or to the bottom 12h of the lower space 12g through the cylindrical body 32a. Therefore, due to the extension part 32 that covers the exhaust hole 13 from the inside, the grease balls pass through the exhaust hole 13 together with the air pressure and scatter to the outside, and the surroundings of the pump device are covered with the exhaust hole 13.
This can ultimately prevent the inconvenience caused by contamination due to grease balls.

Further, the air exhausted from the air cylinder 4 to the upper space 12f in the rod 12 through the exhaust passage 6a reaches the upper space 12f, which has a wider flow area than the exhaust passage 6a narrowed to the exhaust passage 6a, and is further expanded. Rear cylinder body 32 squeezed by cylinder body 32a of exit part 32
It reaches a lower space 12g which is wider than the flow path area of a, and is finally exhausted to the atmosphere through the small diameter exhaust hole 13.

Therefore, the air exhausted from the air cylinder 4 flows through the exhaust passage 6a, which has a narrow flow path area, through the cylindrical body 32a,
The flow velocity becomes relatively high when passing through the exhaust hole 13, and the upper space 12f and the lower space 1 have a large flow path area.
When passing through 2g, the flow rate becomes relatively slow. Therefore, as mentioned above, air flows into the upper space 12f,
While passing through the cylindrical body 32a, the lower space 12g, and the exhaust hole 13, the noise is attenuated and a silencing effect is produced.

That is, when the air piston 6 reciprocates, the switching valve 8 comes into contact with the spring 15 or the spring 16 and generates exhaust noise, but the noise generated when the switching valve 8 switches is suppressed by the above action, and the exhaust noise is reduced. This reduces the noise and makes the pump equipment quieter.

In addition, in the present invention, the above-mentioned cylindrical body 3 is placed inside the rod 12.
2a and a wall portion 32b, the rod 1
The space within 2 can be used effectively and the configuration can be made more compact.

Further, although the air flow path is narrowed by the cylindrical body 32a of the extending portion 32, the air exhaust efficiency is not reduced during pump operation and the operation of the air piston 6 is not obstructed.

Effects of the invention As described above, the pump device according to the invention prevents foreign matter from being discharged to the outside from the exhaust hole even if foreign matter is forcefully blown from the pump drive side cylinder into the pump drive rod by air pressure. For example, even if grease applied to the inner wall of the cylinder on the pump driving side for lubrication is gathered together with the reciprocating movement of the piston and blown off as grease balls, the walls and wall portions that define the hollow part in the rod will not be damaged. The penetrating cylinder allows grease balls to pass through the wall or cylinder and adhere to the bottom of the rod, and as a result, the grease balls are not discharged from the exhaust hole, eliminating the inconvenience of contaminating the vicinity of the exhaust hole. be able to. Furthermore, the flow path of the hollow part of the pump drive rod is constricted by a cylinder between the upper space and the lower space, thereby achieving a noise-muffling effect, thereby attenuating the noise generated during the switching operation of the switching valve. It has features such as being able to make operating noise quieter, and moreover, making effective use of the hollow space formed inside the rod, allowing for a more compact structure.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view for explaining one embodiment of the pump device according to the present invention. 1...Air motor main body, 4...Air cylinder, 4a...Inner peripheral surface, 6...Air piston, 6c
...Peripheral portion, 8...Switching valve, 9...Lower valve body, 1
0... Upper valve body, 12... Rod, 13... Exhaust hole, 15, 16... Coil spring, 18... Pump body, 20... Pump cylinder, 26... Piston, 27... Valve body, 32 ...Extending portion, 32a...
... Cylindrical body, 32b... Wall portion.

Claims (1)

[Claims for Utility Model Registration] The inside of a pump drive side cylinder supplied with air pressure as a pump drive source is divided into an upper chamber and a lower chamber, and an intake passage that supplies the air pressure from the lower chamber to the upper chamber; a pump driving side piston having an exhaust passage for discharging air pressure from the upper chamber; a switching valve for alternately closing the intake passage and the exhaust passage; and a hollow portion inside communicating with the exhaust passage. death,
One side is provided with the pump drive side piston, and the other side is provided with a pump side piston that reciprocates within the pump side cylinder, and the exhaust passage is connected between the pump drive side piston and the pump side piston through the hollow part. a pump driving rod having an exhaust hole communicating with the atmosphere through the pump drive rod; a wall portion provided between the exhaust passage and the exhaust hole and defining a hollow portion of the rod into an upper space and a lower space; It is provided through the wall, one end opens into the upper space, the other end extends at least to a position where the exhaust hole is provided, communicates with the lower space, and has a passage area smaller than the passage area of the hollow part. A pump device consisting of a cylindrical body having a passage area.