JPH0125905B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an accordion-shaped bellows which is disposed within a cylinder of a fluid pressure actuated device and is used with one end in close contact with the cylinder and the other end in close contact with a piston.

Generally, bellows are made of soft synthetic resin, etc., so if a pressure difference occurs between the inside and outside of the bellows, the bellows becomes thick or collapses, so there are places where the pressure difference occurs. There was a drawback that it could not be used for

The object of the present invention is to provide a bellows that can eliminate the above-mentioned drawbacks.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, reference numeral 1 denotes a telescopic bellows made of soft synthetic resin or the like similar to the conventional one, and a first plate member 2 is fitted into the fitting hole 3 in contact with the small diameter portion of the outer periphery of the bellows 1. It has been installed. Further, a second plate member 5 having a through hole 4 in the center is attached to the large diameter portion of the inner circumference of the bellows 1 with its outer circumference contact-fitted. 1st
The plate member 2 has an outer diameter larger than the outer diameter of the bellows 1. Also, small holes 6, 7 are formed in the first and second plate members 2, 5 through which fluid passes between the first plate member 2 and between the second plate member 5 when the bellows 1 expands and contracts.
is drilled.

FIG. 2 shows a bellows constructed as described above applied to a submersible pump, in which 11 is a cylinder, the bottom plate 12 of which is provided with a water passage hole 14 equipped with a first valve 13, and the top plate 15 of which is provided. An opening 16 is formed therein. The upper end of the bellows 1 is in close contact with the periphery of the opening 16, and a water guide hole is provided in the through hole 4 of the second plate member which is fitted in contact with the large diameter part of the inner circumference of the bellows 1. 17, and a rod 18 having a length equal to or longer than the length of the cylinder 11 is arranged to be movable up and down. A piston 20 having a chamber 19 and having a slightly smaller diameter than the bellows 1 is integrally formed at the lower end of the rod 18, and the water guide hole 17 and the chamber 19 are communicated with each other. The lower end of the bellows 1 is in close contact with the upper surface of the piston 20, and a plate member 23 having a water passage hole 22 with a second valve 21 in the center is also in close contact with the lower surface of the bellows 1, thereby closing the chamber 19. . Reference numerals 24 and 25 are filter members for preventing gravel and the like from entering the cylinder 1, 26 is a connecting rod that moves the rod 18 up and down, and 27 is a connecting rod that allows water that has risen through the water guide hole 17 to flow out to the outside. 28 is a guide plate that prevents the rod 18 from wobbling in the lateral direction.

Next, the operation of the pump constructed as described above will be explained.

Put the cylinder 11 into the water. At this time, the bellows 1 enters the water in a contracted state due to the weight of the cylinder 11. When the cylinder 11 reaches the bottom of the well etc., the rod 18 is lowered and the bellows 1
When the rod 18 is raised after being expanded, the bellows 1 is contracted, the first valve 13 is opened, and water flows into the cylinder 11. At this time, the volume inside the bellows 1 decreases and the volume inside the cylinder 11 increases, so the pressure inside the bellows 1 decreases
The pressure becomes higher than the pressure inside the first plate member 2, especially at the moment when the rod 18 rises.
As a result, the bellows 1 does not become medium thick.

And when Rod 18 finishes rising, Rod 1
Lower 8. At this time, the bellows 1 is extended, the second valve 21 opens, and the first valve 13 closes, so the water in the cylinder 11 enters the chamber 19 of the piston 20 through the second valve 21 and enters the water introduction hole 17. enter.
By repeatedly moving the rod 18 up and down, the water that has entered the water guide hole 17 rises and is pumped up. Furthermore, when the rod 18 is lowered, the second valve 21 opens, so that the water pressure of the water level that has risen through the water guide hole 17 is applied to the inside of the cylinder 11, and the difference between the pressure inside the bellows 1 and the pressure inside the bellows 1 becomes large. Therefore, bellows 1 will not collapse.

Fig. 3 shows an application of the above-mentioned bellows to a fluid pressure cylinder that raises and lowers objects using water pressure; 32 is a discharge port provided at the bottom of the cylinder 31;
is a valve. Components that are the same as those in FIG. 2 are designated by the same reference numerals, so their explanation will be omitted.

Next, the operation of the cylinder will be explained.

First, the valve 33 is closed and water is allowed to flow into the cylinder 31 from the water introduction hole 17 of the rod 18.
Then, when the water pressure inside the cylinder increases, the bellows 1 contracts in accordance with the increase, and the rod 18 rises. At this time, the pressure between the cylinder 31 and the bellows 1 becomes higher than the pressure inside the bellows 1,
The second plate member 5 prevents the bellows 1 from being crushed. Next, when the valve 33 is opened and the water in the cylinder 31 is discharged from the outlet 32, the water pressure is reduced and the rod 18 is lowered by its own weight. Note that water is allowed to flow into the cylinder 31 from the water introduction hole 17 of the rod 18, but it may also be made to flow directly into the cylinder 31. Also, although water has been described here using water, oil may also be used. Of course.

As described above, the present invention has the fitting hole of the first plate member contact-fitted with the small diameter part of the outer circumference of the bellows, and the second plate member having the through hole in the center part of the large diameter part of the inner circumference. Since the outer periphery is a contact fit, the bellows will not collapse even if the external pressure becomes higher than the internal pressure, and conversely, the internal pressure will become higher than the external pressure. However, I never become overweight. In addition, since the outer diameter of the first plate member is formed larger than the outer diameter of the bellows, when the bellows is disposed and used in a cylinder of a fluid pressure actuated device, the outer circumference of the first plate member is formed on the inner circumferential surface of the cylinder. The bellows can be prevented from being damaged by friction by preventing the outer periphery of the bellows from coming into sliding contact with the inner peripheral surface of the cylinder. Moreover, as the bellows expands and contracts, the fluid between the first plate members passes through the small holes, so even if the bellows is placed inside the cylinder with the outer periphery of the first plate member in sliding contact with the inner peripheral surface of the cylinder, the expansion and contraction is carried out smoothly. Furthermore, by bringing the outer periphery of the first plate member into sliding contact with the inner peripheral surface of the cylinder, there is no need to bring the piston into sliding contact with the inner peripheral surface of the cylinder; in other words,
Because the piston can be placed with clearance against the inner peripheral surface of the cylinder without frictional contact,
It has excellent effects such as smooth movement of the piston itself.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the bellows of the embodiment, FIG. 2 is a sectional view of the submersible pump, and FIG. 3 is a sectional view of the fluid pressure cylinder. 1... Bellows, 2... First plate member, 3... Fitting hole,
4... Through hole, 5... Second plate member.

Claims (1)

[Scope of Claims] 1. A bellows in the shape of a bellows, which is disposed in a cylinder of a fluid pressure actuated device and is used with one end in close contact with the cylinder and the other end in close contact with a piston, the outer peripheral portion of the bellows The insertion hole of the first plate member is contact-fitted into the small diameter part of the second plate member, and the outer periphery of the second plate member having a through hole in the center is contact-fitted with the large diameter part of the inner circumference part of the second plate member. The bellows is characterized in that its outer diameter is larger than the outer diameter of the bellows, and the first plate member is provided with a small hole through which fluid passes between the first plate members when the bellows expands and contracts. .