LOW PRESSURE STARTER DEVICE FOR PNEUMATIC PUMPS

Abstract

The invention relates to a low-pressure starter device for pneumatic pumps with a pivoting directional air-control valve, characterised in that the low-pressure starter system consists of a retractable push piston actuated by a variable-tension spring that exerts pressure on the shaft of a pivoting element of the body of the directional valve, during start-up, in an end operating positions, said device being formed by a retractable piston, a sealing gasket, a spring and a spring stop.

Claims

1.-7. (canceled)

8. A low pressure starting device for pneumatic pumps with pivoting air control directional control valve, characterised by its low pressure starting system consisting of a retractable push piston driven by a variable tension spring which presses on the shaft of the pivoting element of the directional control valve body, during start-up, in one of the extreme operating positions, driven by an electronic pressure control system which allows the starting pressure to be varied automatically, comprising of: a retractable piston (3.1), a sealing gasket (3.4), a spring (3.2) and, a spring stop (3.3), wherein the spring stop holds the pivoting valve in its start position until it reaches the required minimum start pressure, and once this minimum starting pressure is reached, the low pressure starting device pulls back against the spring pressure and remains in this position until the air motor pressure is released when the air motor is shut down, at which time it returns to its initial position.

9. The low pressure starting device for pneumatic pumps with pivoting directional air control valve of claim 1 wherein it can have a driving fluid other than compressed air but which is equally suitable for driving pneumatic devices such as double diaphragm pneumatic pumps or piston pumps.

10. The low pressure starting device for pneumatic pumps with pivoting directional air control valve of claim 1 wherein the spring (3.2) can be an elastomer whose elastic properties allow the retractable piston to be operated.

11. The low pressure starting device for pneumatic pumps with pivoting directional air control valve of claim 1 wherein the retractable piston can be operated by means of air or pressurised hydraulic fluid instead of the spring.

12. A low pressure starting device for pneumatic pumps with pivoting directional air control valve, characterised in that the pivoting valve provided with an inlet drum and an outlet drum distributes the compressed air to the pump chambers to be driven alternately and both drums are replaceable.

Description

DESCRIPTION OF THE DRAWINGS

[0021] In order to supplement the description herein and to assist in a better understanding of the features of the invention, a set of drawings is attached hereto as an integral part of the description, which illustratively and non-limitingly depicts the following:

[0022] FIG. 1.—A sectional view of the retractable push piston in its exhaust position with a schematic of its interior.

[0023] FIG. 2.—A sectional view of the push piston in its compression position.

[0024] FIG. 3.—A schematic diagram of the interior of the air motor with a pivoting valve and LSD with its push piston in the exhaust position.

[0025] FIG. 4.—A schematic diagram of the interior of the air motor with a pivoting valve and LSD with its push piston in the compression position.

[0026] FIG. 5.—A cross section view of the push piston is shown.

PREFERRED IMPLEMENTATION OF THE INVENTION

[0027] The operation of the low pressure starting device for pneumatic pumps takes place through the interaction of the following pump components using the air pressure which is fed into the motor via the air motor inlet (1). This pressure acts on the pivoting valve (2) and on the LSD's (3) retractable push piston (3.1). When the pressure reaches the set minimum start value the piston retracts backwards (FIG. 2) due to the action of the compressed air and separates from the free-moving pivoting valve (2). The spring (3.2) is compressed and loaded to produce the discharge of force when the pressure inside the air motor is no longer active. The retracting piston can also be operated by means of air or pressurised hydraulic fluid instead of the spring 3.2.

[0028] When the motor is running the compressed air passes alternately through the air inlet ports (6) and, after passing through the inside of the controlling diaphragm or piston pump, it leaves the air motor through the air outlet ports (7) alternately in the direction of the air motor outlet (8).

[0029] Once the air pressure is removed due to the stoppage of the device, the pressure in the inlet chamber of the air motor disappears and the LSD piston automatically pushed by the spring or by any pressure system used for this purpose, returns to its initial position pushing the pivoting valve and keeping it in its starting standby position ready to start again with the working cycle.

[0030] The valve can have a different actuating fluid other than compressed air, but can still be used to actuate pneumatic devices such as pneumatic double diaphragm pumps or piston pumps.