JPH01164801A - Pulsation absorbing device - Google Patents

Abstract

PURPOSE:To enable execution of control of a high order, by a method wherein a nozzle flapper is situated in a device body on the air chamber side, and a strong spring to inversely energize a weak spring flapper to energize the flapper to the nozzle side is brought into contact with the flapper. CONSTITUTION:An exhaust pipe 22 is engaged with a device body 11 on the air chamber side, a nozzle 26 is integrally threadedly mounted to the inner end part of the exhaust pipe 22, and a flapper 31 is separably situated in a position facing the nozzle 26. A comparatively weak compression spring 32 to energize the flapper 31 to the nozzle 26 side is situated between a spring support part 33 of the flapper 31 and a moving separation member 13, and a comparatively strong compression soil spring 57 to energize the flapper 31 in a direction in which it is separated away from the nozzle 26 is situated between the flapper 31 and a flange part 53. Since the displacement tendency of the vibration center of the moving separation member 13 is sensed at an initial state and the vibration center of the moving separation member 13 can be returned to a proper neutral point, this constitution enables execution of analogue control of a high order.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention absorbs and smooths ripples (pulsations) generated in the hydraulic pressure output from a diaphragm pump, piston pump, booster, etc. This invention relates to a pulsation absorbing device.

(Prior Art) Generally, an accumulator has an air chamber and a liquid chamber separated through a movable separation member in the device body, and the gas filled in the air chamber is expanded and contracted to supply the liquid into the liquid chamber. This absorbs and smooths out the ripples in the hydraulic pressure.

In most conventional accumulators, the air chamber is filled with compressed gas until it reaches a certain pressure, and then the air chamber is sealed to maintain that constant pressure.

Such a fixed pressure type accumulator has the disadvantage that it cannot respond to large changes in hydraulic pressure. In other words, normal hydraulic pressure ripples can be absorbed by the expansion and contraction of the air chamber as described above, but since the range of variation of the movable separation member to do this is limited, it is difficult to absorb fluid pressure ripples that exceed the range of variation. There are problems that cannot be addressed.

As a means to deal with such problems, the
There is a device shown in Japanese Patent No.-6725. In the device described in this publication, a pair of valve operation plates are integrally provided to the movable separation member via a rond, and the air supply valve or the exhaust valve is opened by the pair of operation plates.

For example, if the air pressure is too high and the movable separation member is too biased towards the liquid chamber and cannot perform its ripple absorbing function sufficiently, one operation panel opens the exhaust valve, the air pressure in the air chamber is reduced, and the movable separation member is moved toward the liquid chamber. The separating member is returned to a position where sufficient engraving and shrinkage can be achieved.

On the other hand, if the air pressure is too low and the movable separation member is too biased toward the air chamber to perform its ripple absorption function, the air supply valve is opened by the other operation panel, increasing the air pressure inside the air chamber. and the movable separating member is returned to a position where sufficient engraving and retraction can be achieved.

(Problem to be Solved by the Invention) The device described in this publication has a pair of operation plates located at a position where the air supply valve is actuated so that the movable separation member can perform the movement (vibration) necessary for ripple absorption. There is a backlash between the position and the position where the exhaust valve is actuated.

This backlash is naturally necessary for this device to function as an accumulator, but the air pressure in the air chamber will not be reduced until the υ1 air valve is bent by one operation plate, and the pressure in the air chamber will not be reduced until the The air pressure in the air chamber is not increased until the air supply valve is activated by the plate, and in the dead zone area during that time, the air chamber is either in a direction where it should be depressurized or it is in a direction where it should be increased. It is impossible to predict.

For example, even if the same pressure reduction is performed, it is predicted that the pressure in the air chamber should tend to be reduced, rather than starting pressure reduction after the vibration center of the movable separation member is largely displaced toward the liquid chamber as in the past. If the center of vibration of the movable separating member is controlled to return to an appropriate neutral point at an early stage, sophisticated control becomes possible, but this is not possible with conventional on/off control.

An object of the present invention is to provide an analog control type pulsation absorbing device that can sense the displacement tendency of the vibration center of a movable separation member at an early stage and control the vibration center of the movable separation member to return to an appropriate neutral point. It is about providing.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides that an air chamber 14 and a liquid chamber 15 are formed separately through a movable separation member 13 in an apparatus main body 11.12.
Due to the engraving and contraction of the gas filled inside, the liquid chamber 15
In a pulsation absorbing device in which ripples in the hydraulic pressure supplied to the inside are smoothed, a nozzle 2 is installed in the device main body 11 on the air chamber side.
6 is fixedly provided, and a flapper 31 is provided at a position opposite to this nozzle 26 so as to be able to move toward and away from the movable separating member 13. A relatively weak spring 32 that biases this flapper 31 toward the nozzle side A relatively strong spring 57 is provided between the nozzle 26 and the spring 32 to urge the flapper 31 away from the nozzle 26.
A gap 61 is provided between the nozzle 26 and the flapper 31 to adjust the air pressure of the gas supplied into the air chamber 14.

(Function) When the present invention operates as a normal accumulator, the gas in the air chamber 14 expands or contracts with the ripple of the liquid pressure supplied to the liquid chamber 15, and the relatively weak spring The movable separating member 13 vibrates while the movable separating member 32 freely expands and contracts. At this time, the relatively weak spring 32
The flapper 31 expands and contracts within an allowable range that is roughly balanced with the relatively strong spring 57.
is not significantly displaced, the air pressure adjustment gap 61 between the nozzle 26 and the flapper 31 does not change much, and the air pressure inside the air chamber 14 is maintained within a certain range.

On the other hand, for example, the ripple center of the liquid pressure supplied to the liquid chamber 15 tends to rise overall, and the vibration center of the movable separation member 13 gradually rises, causing the relatively strong spring 57 to rise. When the relatively weak spring 32 exceeds the allowable range in which it can freely expand and contract while maintaining a balance between the As the air pressure adjustment gap 61 is brought closer, the air pressure adjustment gap 61 is narrowed accordingly, and the air pressure inside the air chamber 14 increases against the rising liquid liquid, and this increased air pressure causes the vibration center of the movable separation member 13 to move to the appropriate neutral position. will be returned to.

Such automatic adjustment function works similarly even when the ripple center of the liquid pressure supplied to the liquid chamber 15 tends to decrease overall.

(Examples) Hereinafter, the present invention will be described in detail with reference to examples shown in the drawings.

The peripheral edge of the movable separating member 13 is held between the upper device body 11 and the lower device body 12, and the device body 11.1
2, an air chamber 14 and a liquid chamber 1 are connected via this movable separation member 13.
5 are formed separately. The movable separation member 13 is
The diaphragm is a diaphragm that moves up and down depending on the fluctuation of the liquid pressure in the liquid chamber 15, and as the movable separation member 13 moves, the gas filled in the air chamber 14 expands and contracts. Through this action, ripples in the hydraulic pressure supplied into the liquid chamber 15 are absorbed and smoothed.

The lower device main body 12 has a liquid inlet 1 communicating with the liquid chamber.
6 and a liquid outlet 17 are provided.

An exhaust pipe 22 is fitted into the device main body 11 on the air chamber side via an O-ring 21, and this exhaust pipe 22 is connected to its 7 flange portion 2.
3 and the nut 1-25 screwed onto the outer threaded portion 24, the exhaust pipe 22 is fixed to the main body 11 by tightening, and the nozzle 26 is integrally screwed onto the inner end of this exhaust pipe 22, and eventually the air chamber side This nozzle 26 is fixedly provided within the main body 11 of the apparatus.

A flapper 31 is provided at a position facing this nozzle 26 so as to be able to move toward and away from it, and a relatively weak (small spring constant) compression coil spring 32 that urges this flapper 31 toward the nozzle side is attached to a spring receiving portion of this flapper 31. 33 and the center disk 34 of the movable separation member 13.

A pinion 41 is rotatably fitted into the upper part of the device main body 11, and a shaft portion 44 of the pinion 41 is rotatably held by a screw 42 screwed into the device main body 11 via an O-ring 43. There is. A groove 45 into which a cutting edge of a driver or the like is fitted is provided on the end surface of the shaft portion 44 .

The pinion 41 is meshed with a gear 54 that is fitted and screwed onto a flange portion 53 of a spring adjusting threaded tube 52 that is threaded onto a threaded portion 51 of the exhaust pipe 22 .

A guide tube 55 is fitted into the lower part of the exhaust pipe 22 so as to be movable up and down, and a flange portion 56 of the guide tube 55 is engaged with a groove formed around the flapper 31.

The flapper 3 is placed between the opposing flanges 53 and 56 against the relatively weak compression coil spring 32.
A relatively strong compression coil spring 57 (having a large spring constant) is provided that biases the nozzle 1 in a direction away from the nozzle 26 .

An air pressure adjustment gap 61 is provided between the nozzle 26 and the flapper 31, and the air pressure adjustment gap 61 allows gas to be supplied into the air chamber 14 through a ventilation hole 62 formed in the guide tube 55. It communicates with the inside of the air chamber 14.

Compressed air is supplied to the air chamber 14 from an air supply hole 63 provided in the upper part of the device main body 11. A throttle 64 is provided in the compressed air supply pipe system.

-〇- When adjusting the air pressure adjustment gap 61, the pinion 41
The spring adjustment screw tube 52 is rotated together with the gear 54.
is rotated relative to the fixing screw portion 51, and this threaded cylinder 52 is moved and adjusted in the vertical direction, and the relatively strong compression coil spring 5 is rotated.
Adjust the 7 affiliated forces.

Next, the operation of this embodiment will be explained.

When operating as a normal accumulator to remove ripples (pulsation) in the discharge pressure of a diaphragm pump, piston pump, booster, etc., the liquid chamber 1 is
The movable separation member 13 vibrates in response to ripples in the hydraulic pressure supplied into the air chamber 5, and the gas within the air chamber 14 repeatedly expands or contracts.

At this time, the relatively weak compression coil spring 32 freely expands and contracts within a permissible range that maintains a balance with the relatively strong compression coil spring 57, so the flapper 31 does not displace significantly and the nozzle 26・Flapper 3
The air pressure adjustment gap 61 between the air chambers 14 and 14 does not change much, and the air pressure inside the air chambers 14 is maintained within a certain range.

On the other hand, for example, the ripple of the liquid pressure supplied to the liquid chamber 15 tends to fluctuate in the pressure increasing direction as a whole, and the center of vibration of the movable separation member 13 gradually rises, making it relatively weak. When the spring 32 exceeds the allowable range in which it can freely expand and contract, the relatively weak spring 32 moves the flapper 31 closer to the nozzle 26 against the relatively strong spring 57, and the air pressure adjustment gap 61 is narrowed accordingly. The compressed air supplied into the air chamber 14 from the air supply hole 63 passes through the air pressure adjustment gap 61, passes through the inner hole 65 of the exhaust pipe 22, and is exhausted to the outside, so that the exhaust resistance increases and the air chamber The air pressure in 14 increases in opposition to the upwardly increasing hydraulic pressure, and this increased air pressure returns the center of oscillation of movable separating member 13 to its proper neutral position.

Additionally, the ripple center of the liquid pressure supplied to the liquid chamber 15 tends to fall overall, and the vibration center of the movable separation member 13 gradually falls, causing the relatively weak spring 32 to become a relatively strong spring. 57, the flapper 31 is separated from the nozzle 26 by the relatively strong urging force of the spring 57, and the air pressure adjustment gap 61 is enlarged accordingly. The air pressure in the air chamber 14 decreases in sync with the downward trend of the liquid pressure, and the center of vibration of the movable separating member 13 is returned to an appropriate neutral position.

In this embodiment, a diaphragm is illustrated as the movable separation member 13, but a piston may be used instead. In that case, it goes without saying that the piston must be slid within the cylinder.

〔Effect of the invention〕

According to the present invention, a nozzle is fixedly provided in the device main body on the air chamber side, a flapper is provided in a position opposite to this nozzle so as to be able to approach and separate, and a relatively weak force is applied to the flapper toward the nozzle side. A spring is provided between the movable separation member, and a relatively strong spring is provided that urges the flapper in a direction to separate it from the nozzle, and the gas supplied into the air chamber is provided between the nozzle and the flapper. Since a pressure adjustment gap of This enables advanced analog control to control indoor air pressure.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the pulsation absorbing device of the present invention. 11, 12...Device main body, 13...Movable separation member, 14
... Air chamber, 15. Liquid chamber, 26 Nozzle, 31. Flapper, 32. Relatively weak spring, 57. Relatively strong spring, 61. Air pressure adjustment gap.

Claims (1)

[Claims] (1) An air chamber and a liquid chamber are formed separately within the device body via a movable separation member, and the ripples in the liquid pressure supplied to the liquid chamber are smoothed by the expansion and contraction of the gas filled in the air chamber. In the pulsation absorbing device, a nozzle is fixedly provided in the device main body on the air chamber side, a flapper is provided in a position opposite to this nozzle so as to be able to move toward and away from the device, and this flapper is energized toward the nozzle side. A relatively strong spring is provided between the movable separation member and the movable separation member, and a relatively strong spring is provided that urges the flapper away from the nozzle, and a relatively strong spring is provided between the nozzle and the flapper in the air chamber. A pulsation absorbing device characterized by being provided with a gap for adjusting the air pressure of supplied gas.