PISTON PUMP WITH QUICK EXHAUST SLIDE VALVES

Abstract

A pneumatically driven piston pump and its quick exhaust slide valves, which allows air to be evacuated from the piston pump's piston chambers directly into the environment without having to pass through the main distributor valve, in such a way that it does not cause a drop in temperature due to the expansion of the compressed air which freezes the humidity of the air itself, clogging the compressed air circulation ducts and causing the pump to shut down or stall. Such an air-operated piston pump with quick exhaust valves allows the passage of air with low restriction, which increases the efficiency of the piston pump and decreases its compressed air consumption compared to the same air motor without quick exhaust valves.

Claims

1-9. (canceled)

10. A piston pump with quick exhaust slide valves comprising: a single piston in two air piston chambers with reciprocating motion separating the two piston air chambers and two quick exhaust valves, one of the quick exhaust valves for each air piston chamber, which prevent, by means of a sliding mechanism of the quick exhaust valves, the evacuation of the air from the air piston chambers through a main air distribution valve, preventing the main distribution valve from freezing and allowing the air to be discharged directly into the environment from the piston pump.

11. The piston pump with quick exhaust slide valves according to claim 10 wherein the piston pump having a main exhaust system which comprises: at least one compressed air inlet connection; at least one of the main air distribution valve; at least two piston limit switch sensors; the two air piston chambers; at least two of the quick exhaust slide valves; at least one pneumatic piston pump silencing system; and an air chamber piston.

12. The piston pump with quick exhaust slide valves according to claim 10 wherein the quick exhaust slide valves have a guided slide or moving part which allows air to enter the air piston chamber and when the stroke is reversed to be exhausted directly from the air piston chamber into the environment via the main exhaust system of the piston pump.

13. The piston pump with quick exhaust slide valves according to claim 10 wherein the quick exhaust valves comprise a prismatic slide system with a moving part, a stationary sleeve and housing, so that the moving part has linear travel guided by the stationary sleeve and housing.

14. The piston pump with quick exhaust slide valves according to claim 13 wherein each of the quick exhaust slide valves has three ports, one of the ports is always open, and the other two of the ports are closed by a moving part, one of the three ports being in an operating position of a moving part.

15. The piston pump with quick exhaust slide valves according to claim 14 wherein the moving part is displaced by the dynamic pressure of the compressed air, depending on whether it arrives at one port or the other port, the moving part comprises: a compressed air inlet port; an air outlet port to the atmosphere; an air motor port; the moving part of quick exhaust slide valve; the stationary sleeve of quick exhaust slide valve; and quick exhaust slide valve body/housing.

16. The piston pump with quick exhaust slide valves according to claim 10 wherein the quick exhaust valves are independent accessories externally coupled to the piston pump, and the independent accessories are used in any pneumatic system as independent quick exhaust valves.

17. The piston pump with quick exhaust slide valves according to claim 10, wherein the quick exhaust valves electronically operated.

18. The piston pump with quick exhaust slide valves according to claim 13, wherein the moving part of the quick exhaust valves has a part of flexible and elastic material which deforms elastically when the quick exhaust valve receives air under pressure from a convex side of the part, contracting and allowing the passage of pressurised air and, when the quick exhaust valve receives the pressurised air from a concave side of the part, the part elastically deforms and expands to fill an entire cylindrical cross-section of a housing of the quick exhaust valve.

19. The piston pump with quick exhaust slide valves according to claim 18 wherein the part of flexible and elastic material exerts thrust force to move the moving part until the moving part butts against the housing sealing an air inlet port of the quick exhaust valve.

20. The piston pump with quick exhaust sliding valves according to claim 19 wherein the moving part has a part of flexible and elastic material located in the area that contacts the stationary sleeve in one of the operating positions, sealing an air outlet port of the valve.

21. The piston pump with quick exhaust slide valves according to claim 20 wherein the moving part has the two of the parts of flexible material assembled by means of fittings or bolted to a structure of a rigid material, the rigid material being metallic or plastic.

22. The piston pump with quick exhaust slide valves according to claim 12 wherein the moving part is entirely made of a single piece of flexible and elastic material.

22. The piston pump with quick exhaust slide valves according to claim 12, wherein the quick exhaust slide valves are integrated in a pneumatic actuator on which the quick exhaust slide valves are to operate, wherein the pneumatic actuator has housings into which the moving part and stationary parts of the quick exhaust valves are inserted.

23. The piston pump with quick exhaust slide valves according to claim 12, wherein the design of the quick exhaust slide valves prevents the possibility of misalignment of the moving part, ensuring the guidance of said moving part, which makes it possible to lengthen travel of the moving part to increase the section of the compressed air passage, reducing load loss and improving the performance of the quick exhaust slide valve with respect to designs of the same size, which have a short travel so that the moving part, without guidance, does not become misaligned and cause leaks and/or malfunctioning.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0008] The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:

[0009] FIG. 1a is a pneumatic diagram of the pneumatically driven piston pump with quick exhaust valves and slide mechanism;

[0010] FIG. 1b is a longitudinal section of the piston pump of a pneumatically driven piston pump with quick exhaust valves and slide mechanism;

[0011] FIG. 2a is a pneumatic diagram of the pneumatically driven piston pump with quick exhaust valves and slide mechanism, operating in a downward direction;

[0012] FIG. 3 is a pneumatic diagram of the pneumatically driven piston pump with quick exhaust valves and slide mechanism, operating in an upward direction;

[0013] FIG. 4a is a diagram of the quick exhaust valve with its air inlet port, air outlet port, motor port, moving part, stationary part and housing;

[0014] FIG. 4b is a longitudinal section of the quick exhaust valve with its air inlet port, air outlet port, motor port, moving part, stationary part and housing;

[0015] FIG. 5 is a diagram of the quick exhaust slide valve in the air release position; and

[0016] FIG. 6. is a diagram of the quick exhaust slide valve in the air inlet position.

DETAILED DESCRIPTION OF THE INVENTION

[0017] The air motor that drives the piston pump has a power piston that separates the two air chambers that make up the pump and moves alternately from one chamber to the other, causing the pump to move. The air motor also has a compressed air inlet to a main air distribution valve, which feeds compressed air alternately into the air piston chambers to cause their reciprocating motion aided by the actuation of the end-of-stroke sensors. The quick exhaust valves are located in the communication ports with the two air piston chambers and are intended to evacuate the compressed air from the piston pump piston chambers without passing through the main compressed air distribution valve of the motor.

[0018] Two quick exhaust valves are required for each pneumatically driven piston pump: one evacuates the air from the upper air piston chamber and the other evacuates the air from the lower air piston chamber. In this way, both chambers have their own valve for evacuating air directly to the outside, preventing the air to be evacuated from having to pass through the main air distribution valve and preventing the sudden expansion of the compressed air from causing the generation of ice in the main distribution valve that could prevent its normal operation and draught, and also reducing the pressure loss from the extraction of compressed air from the motor to the atmosphere. The quick exhaust valves with slide system have a movable element which has a dual function: firstly, when in the air inlet position, it allows air to enter the corresponding air piston chamber; secondly, when in the air exhaust position, it allows air from air piston chamber to escape directly into the atmosphere via the pump's silencing system in turn prevents the air from having to return to the main distributor valve before it is released into the environment.

[0019] The invention consists of a piston pump and two quick exhaust valves with slide mechanism, each consisting of: [0020] a moving part. Such a moving part may consist of a single piece of elastomeric material or an assembly consisting of a rigid structure and two elastomeric sealing elements assembled to it. This moving part alternates between two positions depending on whether compressed air is entering or leaving the air piston chamber, closing the corresponding air port (either the one communicating with the main distributor valve or the one communicating to the atmosphere) and leaving the other one open, alternately. [0021] a stationary sleeve. The sleeve consists of a rigid part that houses and guides the moving part and provides a sealing layer at the air passage port to the atmosphere. [0022] a housing containing the moving part and the stationary cylinder sleeve, which in the case of piston air motors may be part of the construction parts of such a motor that benefit from the smaller size required to achieve the same performance as traditional exhaust valves, allowing the motor construction parts to be smaller, or of the same size, but with superior pneumatic performance . . . ;.

[0023] Compared to existing quick exhaust valves, this invention improves on existing quick exhaust valves by removing obstacles in the air passage from the main air distribution valve to the air piston chamber. This is achieved with a moving part of greater length than usual, allowing it to seal against a surface outside the geometric space between the air piston chamber port and the main distributor valve port. Moreover, since the sleeve and the moving part are prismatic in shape, the moving part is always guided by the sleeve, thus avoiding any possibility of misalignment that could lead to irregular operation or even failure, which can occur with existing valves.

[0024] This piston pump with quick exhaust valve has one of its applications in pneumatically driven reciprocating piston pumps for fluid transfer. The piston pump with quick exhaust valve allows the air stored in the air piston chambers of the piston pump's air motor to exhausted directly into the environment without passing through the internal ducts of the motor or the main air distribution valve, and without causing it to freeze. This prevents the creation of ice in the motor's air ducts and in its main distributor valve, which can cause the piston pump to stop and stall. On the other hand, this arrangement of the quick exhaust valves minimises pressure losses in the motor's operating air circuit, increasing its efficiency and reducing compressed air consumption.

[0025] The piston pump (FIG. 1a) consists of: [0026] a compressed air inlet connection (1), [0027] a main air distributor valve (2), [0028] two piston limit switch sensors (3a and 3b), [0029] air piston chambers (4a and 4b), [0030] quick exhaust slide valves (5a and 5b), [0031] pneumatic piston pump silencing system (6), [0032] air chamber piston (7)

[0033] Quick exhaust valves with slide mechanism (FIG. 4a) are composed of: [0034] compressed air inlet port (7), [0035] air outlet port to the atmosphere (8), [0036] air motor port (9), [0037] moving part of quick exhaust slide valve (10), [0038] stationary part of quick exhaust slide valve (11), [0039] quick exhaust slide valve body/housing (12),

[0040] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.

[0041] FIG. 1a shows the operating diagram of the piston pump air motor of which a sectional view is shown in FIG. 1b with all its component systems in the position of filling the upper piston chamber (4a) and emptying the lower piston chamber (4b).

[0042] When the main air distribution valve (2) is in the downward position (FIG. 2), it sends compressed air to the air inlet of the upper quick exhaust valve (5a) and communicates the air inlet of the lower quick exhaust valve (5b) to the atmosphere. The dynamic air pressure is responsible for positioning the moving part of the upper quick exhaust valve (5a) to allow air to flow into the upper air piston chamber (4a), and for positioning the moving part of the lower quick exhaust valve (5b) to exhaust air from the lower air piston chamber (4b) to the atmosphere via the silencer (6), preventing the exhaust air from returning to the main distributor valve (2) and protecting it against temperature drops and freezing. Since the upper air piston chamber (4a) is supplied with compressed air and the lower air piston chamber (4b) is connected to the atmosphere, the air piston chamber (7) moves downwards.

[0043] When the air chamber piston (7) reaches its downward stroke end, the lower stroke end sensor (3b) is actuated by the air piston (7), causing the main distributor valve (2) to switch to its upward position as shown in the figure (FIG. 3).

[0044] When the main air distributor valve (2) is in the upward position (FIG. 3), it sends compressed air to the air inlet of the lower quick exhaust valve (5b) and communicates the air inlet of the upper quick exhaust valve (5a) to the atmosphere. The dynamic air pressure is responsible for positioning the moving part of the lower quick exhaust valve (5b) to pass air into the lower air piston chamber (4b), and for positioning the moving part of the upper quick exhaust valve (5a) to exhaust air from the upper air piston chamber (4a) to the atmosphere via the silencer (6), preventing the exhaust air from returning to the main distributor valve (2) and protecting it against temperature drops and freezing. Since the lower air piston chamber (4b) is supplied with compressed air and the upper air piston chamber (4a) is connected to the atmosphere, the air piston moves upwards.

[0045] The limit switch sensors (3a and 3b) can be of any type to actuate the main distributor valve (2) and can have sensing technology of any type such as pneumatic, electrical or mechanical. These sensors may be independent elements attached to the motor from the outside or they may form a constructive part of the motor itself.

[0046] FIG. 4b shows a sectional view of a quick exhaust valve with a slide mechanism, the housing of which is part of one of the piston pump parts.

[0047] The quick exhaust slide valve (5a, 5b) has two operating positions which alternate with each change of position of the main air distributor valve (2).

[0048] One of these two positions, the air evacuation position (FIG. 5), occurs when there is no compressed air at the compressed air inlet port (7), because the main distributor valve (2) is in the position that communicates the port (7) of the quick exhaust valve in question with the atmosphere. In this position, the air piston chamber (4a or 4b) to which the quick exhaust slide valve (5a or 5b) is connected has compressed air which must be exhausted to the atmosphere. The compressed air enters the quick exhaust valve with slide mechanism through the air motor port (9), and the dynamic air pressure pushes the moving part (10) to close the compressed air inlet port (7). When the moving part (10) is placed in this position, the air outlet port to the atmosphere (8) remains open, so that the compressed air in the piston chamber (4a or 4b) is exhausted to the atmosphere.

[0049] The other operating position of the quick exhaust slide valve (5a, 5b), in which the air inlet is represented in the figure (FIG. 6), is when compressed air is present at the compressed air inlet port (7), because the main distributor valve (2) has been positioned to communicate air pressure to this quick exhaust valve with slide mechanism (5a or 5b).

[0050] In this position, the compressed air in the air inlet port (7) pushes the moving part (10) and the dynamic pressure of the air causes the moving part (10) to position itself and maintain the position shown in the image (FIG. 6) and the flexible element of the moving part to deform elastically, allowing the air to pass through. In this way, the compressed air flows to the air motor through the motor port (9), while simultaneously the moving part (10) closes the air outlet port to the atmosphere (8).

[0051] The passage from one position to another of the moving part (10) is always a guided linear movement, as part of the moving part (10) remains inside the stationary part (11), in the form of a prismatic or sliding system, with reduced play between the two parts to ensure the guiding effect. This avoids misalignment of the moving part (10) that may cause malfunction due to poor sealing or deterioration of the seal (10).