GB2115076A

GB2115076A - Apparatus for continuous supply of high-pressure fluid

Info

Publication number: GB2115076A
Application number: GB08222126A
Authority: GB
Inventors: Yoshiichi Yamatani
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-02-12
Filing date: 1982-07-30
Publication date: 1983-09-01
Also published as: CA1202822A; SE8204320D0; GB2115076B; AU8718382A; DE3234950A1; SE8204320L; JPS58142001A

Abstract

Apparatus for continuous supply of high-pressure fluid comprises pressure- intensifying pumps with pressure- intensifying cylinders 1 and 2 within which operate pistons or rams 3 and 4 respectively. They feed, through non- return discharge ports 13 and 14, a common gathering chamber 17. If desired, two or more separate such chambers 17 can be used. The, or each, chamber 17 feeds through another non- return valve 18 the supply duct 19 provided with accumulator 20. Use of such a gathering chamber 17 reduces noise and gives smoother operation by absorbing sudden impact pressure changes at piston extreme positions. <IMAGE>

Description

SPECIFICATION Apparatus for continuous supply of high-pressure fluid The present invention relates to an apparatus for the continuous supply of high-pressure fluid, of the type in which pressure intensifying pumps, each including a pressure-intensifying cylinder and a piston or ram are driven, out of phase with each other, by a common drive.

Hitherto, when high-pressure fluid is produced and supplied continuously by operating pressureintensifying pumps out of phase, the production of the high-pressure fluid in a given pressureintensifying cylinder stops momentarily at piston top dead centre, corresponding for example to bottom dead centre of a piston or a ram in another pressure-intensifying cylinder. A sudden change of pressure thereby occurs and a noise is generated. To reduce this noise, Japanese Patent Application No.

54-122974 proposes that, just before a piston or a ram in one pressure-intensifying cylinder reaches top dead centre, it should operate a device to start the piston or ram in the other pressure-intensifying cylinder. However, impact pressure at this start point is unavoidable. Also, because the pressureintensifying cylinder is connected directly with a duct through a non-return valve, the impact pressure is transferred to the duct and smooth operation is prevented. In order to reduce noise and improve operation, an accumulator is used, but the volume of such an accumulator must be very large to counteract the effect of the impact pressure.

The present invention sets out to reduce the noise and provide smooth operation in apparatus for the continuous supply of high-pressure fluid, preferably by providing small-scale apparatus capable of performing the desired operation with good energy efficiency.

In one aspect the present invention consists in apparatus for the continuous supply of highpressure fluid of the type in which pressureintensifying pumps each including a pressureintensifying cylinder and a piston or ram are driven, out of phase with each other, by a common drive; wherein a discharge port in each pressureintensifying cylinder is connected through a nonreturn valve to a gathering chamber; the or each gathering chamber is connected to a supply duct for high-pressure fluid through a further non-return valve; and an accumulator is connected to the supply duct on the other side of the further nonreturn valve or valves from the or each gathering chamber.

The invention will be more fully described, by way of example with reference to the accompanying drawing, in which: Figure 1 is a diagram illustrating an embodiment of the present invention.

Pressure-intensifying cylinders 1 and 2 contain respective pistons or rams 3 and 4. Cams 5 and 6 respectively are operatively connected to these pistons or rams 3 and 4. A common drive gives the piston or rams oppositely phased reciprocating movements, e.g. simultaneous equal and opposite motions. Pressure-intensifying chambers 7 and 8 defined within the pressure-intensifying cylinders 1 and 2 respectively are provided with suction ports 11 and 12 for fluid, having non-return valves 9 and 10.

They are also provided with discharge ports 13 and 14 for high- pressure fluid. Discharge ports 13 and 14 are connected to gathering chamber 17 for high pressure fluid through non-return valves 15 and 16 respectively. Gathering chamber 17 is connected to a supply duct 19 for high pressure fluid through non-return valve 18, and an accumulator 20 is connected to the supply duct 19.

Gathering chamber 17 is common to the respective pressure-intensifying cylinders 1 and 2 in the example illustrated. However, two gathering chambers 17 for high-pressure fluid may be arranged separately, one for each pressure-intensifying cylinder, and be both connected to the supply duct 19 through separate non-return valves.

A safety valve 21 is also provided for the gathering chamber 17. Reference 22 designates an exhaust port for the supply duct 19.

The operation of the apparatus illustrated is as follows: The pistons or rams 3 and 4 are operated in opposite phase by rotation of the cams 5 and 6. Fluid is drawn in the pressure-intensifying chamber7 and 8, through the suction ports 11 and 12 and through non-return valves 9 and 10 on the downstroke of the relevant piston or ram. High- pressure fluid is pumped into the gathering chamber 17 through the discharge ports 13 and 14. The fluid drawn into the pressure-intensifying chambers 7 and 8 is subject to an increase of pressure during the upstroke of the relevant piston or ram 3 and 4. High pressure fluid eventually reaches the supply duct 19 via the non-return valve 18 and is exhausted from the exhaust port 22.

When operation is considered in detail it can be established that fluid in, say, cylinder 1 opens the non-return valve 15 by overcoming pressure in the gathering chamber 17. Consequent increase of pressure in the gathering chamber 17 eventually opens non-return valve 18 and feeds duct 19. When the piston or ram 3 reaches top dead centre, the pressure in the chamber 7 starts to decrease. The valve 15 closes. The pressure in the gathering chamber 17 also decreases momentarily as this takes place, and pressure in the supply duct 19 overcomes the pressure in the gathering chamber 17 by the action of the accumulator 20 and thus also closes non-return valve 18. Subsequently, nonreturn valve 16 opens in accordance with the pressure of fluid caused by the upstroke of the piston or ram 4 in the pressure-intensifying cylinder 2 on the other side. The cycle above is thus repeated, and so on.

The high impact pressure generated at that moment when the pistons or rams 3 and 4 start to ascend from their lower dead centre is absorbed by a buffer action. Pressure change in the supply duct 19 and consequent noise and damage by impact pressure are prevented and the apparatus performs smoothly.

The driving gear for the pistons or rams of the pressure-intensifying cylinder in the abovementioned embodiment can use a crank mechanism or oil pressure mechanism as well as a cam mechanism as shown. However, the change of reciprocation speed becomes larger by the rotation of the crank mechanism, and it is not always appropriate to use such a crank mechanism in the apparatus for generating ultrahigh pressure. Oil-pressure devices may be utilised for the drive but such devices are sometimes complex and energy losses may occur. A device as shown, utilizing cams, converts a rotary motive power directly into a reciprocation. The shape of cam can be optimised to regulate a reciprocation of the piston or ram with good energy efficiency. This device can effect accurate power transmission with a simple construction.

Claims

1. Apparatusforthe continuous supply of highpressure fluid of the type in which pressureintensifying pumps each including a pressureintensifying cylinder and a piston or ram are driven, out of phase with each other, by a common drive: wherein a discharge port in each pressureintensifying cylinder is connected through a nonreturn valve to a gathering chamber; the or each gathering chamber is connected to a supply duct for high-pressure fluid through a further non-return valve; and an accumulator is connected to the supply duct on the other side of the further nonreturn valve or valves from the or each gathering chamber.

2. Apparatus as claimed in claim 1 having a common gathering chamber for the pressureintensifying pumps.

3. Apparatus as claimed in claim 1 or 2 which comprises a cam mechanism to move the piston or ram in each pressure-intensifying cylinder.

4. Apparatus for the continuous supply of highpressure fluid substantially as herein described with reference to, and as illustrated in the accompanying drawing.