JPS6043184A - Reciprocating pump device - Google Patents

Abstract

PURPOSE:To prevent the invasion of fluid into the main body of an air cylinder and improve the durability of the device by a method wherein one end of bellows, fitted into the rod of a piston, is secured to the main body of the air cylinder at a position apart from the surface of the rod by a predetermined distance while the other end thereof is secured to the surface of the rod. CONSTITUTION:Bellows 22a, 22b are fitted into the rods 4a, 4b of pistons 16a, 16b and are covered while the one ends of the bellows 22a, 22b are secured to the air cylinder main body 2 at the positions apart from the surfaces of the rods 4a, 4b by predetermined distances (h) and the other ends thereof are secured to the outer peripheral surfaces of the rods 4a, 4b. According to this method, the fluid will never be adhered to a part whereat the rods 4a, 4b slide on the main body 2 of the air cylinder and, therefore, the invasion of the fluid into the main body 2 may be prevented perfectly. Pump chambers 23a, 23b are provided with surge tanks 21a, 21b to mitigate the impact of surging. According to such constitution, the durability of the device may be improved remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reciprocating pump device, and more particularly to a reciprocating pump device.
The reciprocating pump device of the present invention integrally connects an air piston sliding within an air cylinder body and a piston reciprocating within the pump device with a rod, and a seal attached to the inner wall of the housing of the pump device is attached to the piston. In a fluid pump device that allows contact with the outer circumferential surface of the piston rod, - one end of the bellows is fixed to the air cylinder body at a position a predetermined distance from the surface of the rod, and the other end of the bellows is fixed to the surface of the rod.

Conventional piston pumps have a structure in which the packing is constantly rubbing against the inside of the cylinder or the rond surface, and there is also a small gap between the piston and the cylinder, so the packing is often worn, especially when using materials containing silica sand, and the packing has to be replaced frequently. There was a weak point that I had to do. In addition, as the piston rod reciprocates inside and outside the cylinder, the material attached to the rod comes into contact with the outside air, which may cause malfunction, especially if the material is quick-drying, so measures must be taken to prevent it from sticking. was there.

An object of the present invention is to solve the above-mentioned problems and provide a pump device suitable for pumping materials including aggregate.

An embodiment of the present invention will be described below with reference to the drawings. 1a is the pump device on the right side. Compressed air passages 13 and 14 are opened in the air cylinder main body 2, which is a cylindrical shape with a bottom. The air cylinder body 2 is also provided with pins 28 and 29 for detecting the ultimate position of the air piston 15 (described later). A cylindrical intermediate housing 3a is fixed to one end of the air cylinder main body 2, and forms a pump chamber 23a inside. A material suction pipe 11a and a surge tank 21a are attached to the intermediate housing 3a.

An end housing 20a is attached to the end of the intermediate housing 3a with a seal pressing plate 18a in between. A pump chamber 24a is formed inside the end housing 20a. FIG. 2 shows an enlarged view of part A, and shows the seal presser plate 18.
a supports a seal 19a made of a ring-shaped flexible elastic body in cooperation with the end housing 20a. Seal 19a
The distal end portion forms a lip 31a'r.

A check valve 25a is attached to the end of the end housing 20a. A valve seat 32a is provided at the boundary between the end housing 20a and the check valve 25a, and when there is no pressure, the ball 26a is seated on the valve seat 32a by the elastic force of the spring 27a. The figure shows the 0 check valve 25a in the open state where material is being fed under pressure.
is in communication with the discharge pipe 12a.

An air piston 15 is slidably provided inside the air cylinder body 2. A piston 16a is attached to the tip of a rod 4a extending from the air piston 15, and the piston 16a can reciprocate within the pump chambers 23a and 24a. It is necessary to provide a gap between the inner walls of the pump chambers 23a and 24a and the outer peripheral surface of the piston 16a. In the pump chamber 23a, a telescopic bellows 22a is fitted to the rod 4a, and one end of the bellows 22a is fixed to the air cylinder body 2 at a position 33a a predetermined distance from the surface of the rod 4a. The other end is at position 12 above the rod 4a.
It is secured to the rod 4a at 34a. On the opposite side of the air piston 15, a rod 4b and a piston 16b are provided symmetrically to the rod 4a and the piston 16a.

A bellows 22b is fitted onto the rod 4b.

A pump device 1b is provided symmetrically to the pump device 1a with the air cylinder main body 2 as the center of symmetry. That is, with the air cylinder body 2 as the center of symmetry, the intermediate housing 3b, the end housing 20b1, and the check valve 25b are provided on the left side of the air cylinder body 2, symmetrically with the intermediate housing 3a, the end housing 20a, and the check valve 25a. It is being A pump chamber 23b is formed in the intermediate housing 3b, and includes a material suction pipe 11b and a surge tank 21b.
is installed. Pump chambers 23b and 24b are provided in the intermediate housing 3b and the end housing sink 2ob, respectively.
is formed, and a seal 19 is formed by the seal pressing plate 18b.
I support b'e. The check valve 25b communicates with the discharge pipe 12b. 32b is the valve seat. 26b is a ball, and 27b is a \pull.

10 is a material can containing a material containing aggregate such as silica sand or a high viscosity material M'.

FIG. 4 is a 70-seat of the switching mechanism. 6.7.8 is a switching valve, 9 is a pressure reducing valve, 025a is a check valve of the pump device 1a on the right side, 25b is a check valve of the pump device 1b on the left side, and 10 is a material can.

The operation of the apparatus of the present invention having the configuration described above will be explained. Right pump device 1a and left pump device = t
In case b, the suction stroke and the discharge stroke are performed in reverse, so the mechanism for sucking and discharging the material will be explained with respect to the pump device 1a on the right side. If the pump starts running,
First, the air in the pump chamber and the suction pipe 11a is discharged and then the material is discharged, but since the principle of operation is the same, here we will explain the state in which the pump chamber and the suction pipe 11a are filled with material.

Compressed air enters the cylinder through the switching valve 6 and the passage 13 provided in the air cylinder body 2, pushing the air piston 15 and piston 16a to the right. Since the volume of the pump chamber 24a formed in the end housing 2Oa is small, the material inside is pressurized. As shown in FIG. 2, the pressurized material pushes against the lip 30a of the piston 16a and the lip 31at of the seal 19a in the direction of arrow C. Here, the lip 31a is held down by the seal pressing plate 18a, and when the curve of the lip 31a is in the opposite direction, the lip 31a is pressed against the circumferential surface of the piston 16a due to the pressure. improve. The pressurized material pushes the ball 26a of the check valve 25a and is discharged through the discharge pipe 12a.

When the air piston 15 reaches the right extreme position, the switching valve 8
When the bottle 28 is pushed, the switching valve 6 is operated, compressed air is sent into the cylinder from the passage 14, and the air piston 15 is
In contrast, the piston 16a is pushed to the left. The rod 4a moves into the air cylinder body 2 with the movement of the air piston 15, but since it is sealed by the bellows 22a, it does not touch the material and is therefore prevented from entering the air cylinder body 2. . As the piston 16a moves to the left, the volume of the pump chamber 24a increases, no negative pressure is created inside, and the ball 26a of the check valve 25a is pressed against the valve seat 32a. When the piston 16a is further pushed to the left, the negative pressure becomes thicker, and as shown in FIG.
A phenomenon that some amount of water enters the pump chamber 24a from between the lip 31a of the piston 9a and the piston 16a occurs.

In addition, by moving the piston 16a, the pump chamber 23
The volume of a is actually small and is discharged from the suction pipe 11a, but the volume of the pump chamber 23b of the left pump device 1b increases by the same volume, so the material is discharged from the suction pipe 11a, ll
It only moves through b.

The effects of the present invention are as follows.

In the present invention, a bellows is fitted and covered over the histone rod, one end of the bellows is fixed to the air cylinder body at a predetermined distance from the surface of the rod, and the other end of the bellows is fixed to the outer peripheral surface of the rod. Therefore, there is no risk of particles adhering to the part where the rod slides on the air cylinder body, and this completely prevents particles from entering the air cylinder, allowing the equipment to operate for a long time without any problems. can be used.

In FIG. 3, considering the stroke in which the piston 16a moves to the left, the lip 31a of the seal 19a
Immediately before the piston 16a leaves the lip 31a, the negative pressure in the pump chamber 24a reaches its maximum, and at the moment the piston 16a leaves the lip 31a, the pressure in the pump chamber 23a drops suddenly and a pressure wave is generated.

At this time, assuming that the surge tank 21a is not provided, a water hammer effect occurs due to the generation of this pressure wave, and the alarming pressure changes are repeated in the pump chamber 23a. The bellows 22a repeatedly expands, collapses, and collapses in response to the pressure change, which may result in damage. Since the present invention provides a surge tank in the pump chamber, it is possible to soften the impact, protect the bellows, and improve durability. To explain more specifically what it means to soften the impact, firstly, the gas trapped in the upper part of the surge tank (usually air, but it is also possible to use a gas other than air). is maintained at atmospheric pressure and has the effect of releasing pressure waves.

Second, when the pressure within the pump chamber changes, material within the surge tank moves in and out of the pump chamber, mitigating pressure changes within the pump chamber. That is, when the pressure in the pump chamber drops, material is replenished into the pump chamber to reduce the pressure drop.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the apparatus of the present invention, FIG. 2 is an enlarged view of section A in FIG. 1, and FIG. 4 is a flow sheet of the switching mechanism. 1a. 0. Right pump device lb,, left pump device 2゜9. Air cylinder body 3a-3b...Intermediate housing 4a%4b...Rod 6.7.8. . -Switching valve 9...pressure reducing valve 15,...air pistons 16a, 16b, -pistons 19a, 19b, -seals 20a, 20b. 0. End flange 21a, 21
b, 6. Surge tanks 22a, 22b,... bellows 25a, 25b --- Check valve agent Tsuneteru Aragaki Figure 2 Figure 3 brt Figure 4

Claims (1)

[Claims] / An air piston that slides within the air cylinder body and a piston that reciprocates within the pump device are integrally connected by a rod, and a seal attached to the inner wall of the housing of the pump device is attached to the piston. In a fluid pump device, a bellows is fitted into the rod of the piston, one end of the bellows is fixed to the air cylinder body at a position a predetermined pressure kl away from the surface of the rod, and the other end of the bellows is fixed to the air cylinder body at a position a predetermined pressure kl away from the surface of the rod. A reciprocating pump device characterized in that the end is fixed to the surface of a rod. (c) An air piston sliding inside an air cylinder body and a piston reciprocating inside the pump device are integrally connected by a rod, In a fluid pump device in which a seal attached to the inner wall of the housing of the pump device can come into contact with the outer peripheral surface of the screw, a bellows is fitted onto the rod of the piston, and one end of the bellows is attached to the surface of the rod. The bellows is fixed to the air cylinder body at a predetermined distance from the rod, the other end of the bellows is fixed to the surface of the rod, and a surge tank is provided in the pump chamber to soften the shock.