WO2021260408A1

WO2021260408A1 - Head for a volumetric pump

Info

Publication number: WO2021260408A1
Application number: PCT/IB2020/055855
Authority: WO
Inventors: Enrico Vezzosi; Costantino COCO
Original assignee: Comet S.P.A.
Priority date: 2020-06-22
Filing date: 2020-06-22
Publication date: 2021-12-30

Abstract

A head for a volumetric pump comprises: a pumping chamber (3); a suction opening (4) placed in communication with the pumping chamber (3); a suction valve (5) arranged along the suction conduit to only enable flow directed towards the pumping chamber (3); a delivery opening (6) placed in communication with the pumping chamber (3); and a delivery valve (7) is arranged along the delivery conduit (6) to only enable flow coming from the pumping chamber (3). The suction opening (4) is provided with a seat (41), inside which the suction valve (5) is housed, and a suction fitting (51), removably associated with the seat (41) for retaining the suction valve (5) in position. The delivery opening (6) is provided with a seat (61), inside which the delivery valve (7) is housed, and a delivery fitting (71), removably associated with the seat (61) for retaining the suction valve (5) in position.

Description

“Head for a volumetric pump”

DESCRIPTION

The present invention relates to a head for a volumetric pump, and a volumetric pump provided with the head according to the invention.

Generally, volumetric pumps comprise at least one cylinder which is provided with a suction valve, located at a suction opening of the pump, and a delivery valve, located at a delivery opening of the pump. The suction opening and the delivery opening are in communication with a pumping chamber of the pump, i.e. a space inside which the piston, when performing its alternated stroke, sucks fluid through the suction opening and compresses it at the delivery opening. The suction and delivery valves regulate the one- directional flow of the fluid from the suction opening towards the delivery opening.

In currently available pumps, the suction valves and the delivery valves are enclosed inside the head of the pump. Every intervention on the valves therefore requires the dismounting of the head, which is frequently connected to the body of the valve through a high number of screws. The operation is therefore relatively laborious and, given that the valves are parts subject to notable wear, especially in the presence of abrasive fluids, in many sectors it must be repeated with a certain frequency. In some cases, to prevent the disassembly of the head, the latter is provided with dedicated openings for access to the valves. Such openings are provided with respective closing plugs. The creation of such access openings complicates the head production process and often implies an increase in the dimensions of the heads.

The main aim of the present invention is that of offering a head for a volumetric pump that allows access to the suction and delivery valves in a simple and quick way.

Further characteristics and advantages of the present invention will become more apparent in the following detailed description of an embodiment of the present invention, illustrated by way of non limiting example in the attached figures, wherein:

- figure 1 is a sectional view of a volumetric pump provided with a head according to the present invention;

- figure 2 is an enlargement of the head zone of figure 1.

The head for a volumetric pump according to the present invention comprises a main body (1), predisposed to be connected to the body (10) of a pump. The head comprises a pumping chamber (3), intended, in use, to house at least one portion of a pumping element (2) which, when activated in a known way, performs alternate suction and delivery cycles of a fluid, respectively at the inlet and the outlet of the pumping chamber (3).

The head comprises a suction opening (4), placed in communication with the pumping chamber (3). The suction opening (4) is predisposed to place the pumping chamber (3) in communication with an external environment to the head. A suction valve (5), known in the sector, is associated with the suction opening (4), to allow only direct flow towards the pumping chamber (3). The suction valve (5) is substantially a one-directional valve, which can be activated between an open configuration and a closed configuration, which is provided with a shutter which is kept in the closed position by an elastic element. During the suction step, the depression that is created in the head chamber (3) by the pumping element (2) produces the movement of the shutter into the open position and the suction of the fluid into the head chamber (3). During the delivery step, the pressure created in the head chamber (3) acts in accordance with the elastic element, bringing the shutter into the closed position.

In the embodiment represented, which is preferred but not exclusive, the suction opening (4) is afforded within the main body (1) concentrically to a longitudinal axis (Z). The suction opening (4) is connected, on one side, to the pumping chamber (3), whereas on the other side it is open to an external environment with respect to the head.

The head further comprises a delivery opening (6), placed in communication with the pumping chamber (3). The delivery opening (6) is configured to place the pumping chamber in communication (3) with an external environment to the head. A delivery valve (7) is arranged along the delivery conduit (6) to only enable flow coming from the pumping chamber (3).

The delivery valve (7) is substantially a one-directional valve, which can be activated between an open configuration and a closed configuration, which is provided with a shutter which is kept in the closed position by an elastic element. During the delivery step, the depression that is created in the head chamber (3) by the pumping element (2) produces the movement of the shutter into the open position and enables the ejection of the fluid from the head chamber (3). During the suction step, the depression created in the head chamber (3) acts in accordance with the elastic element, bringing the shutter into the closed position.

In the embodiment represented, which is preferred but not exclusive, the delivery opening (6) is afforded within the main body (1) concentrically to a longitudinal axis (Z). For construction convenience, preferably, but not necessarily, the longitudinal axis of the delivery opening (6) is aligned with the longitudinal axis (Z) of the suction opening (4). The delivery opening (6) is connected, on one side, to the pumping chamber (3), whereas on the other side it is open to an external environment with respect to the head. Advantageously, the suction opening (4) is provided with a seat (41), inside which the suction valve (5) is housed, and a suction fitting (51), removably associated with the seat (41). The suction fitting (51) is configured to retain the suction valve (5) in position in the seat (41).

The suction fitting (51) comprises an attachment means to a fluid supply conduit. In the pump according to the present invention, the suction fitting (51), removably connected to the seat (41), also performs a plug or cover function for the suction valve (51). Access to the suction valve (5) itself is therefore very easy, only requiring the removal of the suction fitting (51).

In the embodiment represented, which is preferred but not exclusive, the seat (41) of the suction opening (4) comprises a bottom wall (42) in contact with which the suction valve (5) is arranged. The bottom wall (42) is substantially defined by a shoulder of the suction opening (4), arranged transversally to the longitudinal axis (Z) of the suction opening (4). At an opposite end to the bottom wall (42), the seat (41) is open towards the outside and is provided with a coupling means to the suction fitting (51). Such coupling means preferably comprises a thread. A sealing means is interposed, in a known way in the sector, between the suction fitting (51) and the seat (41) and between the suction fitting (51) and the suction valve (5). When the suction fitting (51) is connected to the seat (41), the suction valve (5) is kept in position inside the seat (41).

Advantageously, the delivery opening (6) is provided with a seat (61), inside which the delivery valve (7) is housed, and a delivery fitting (71), removably associated with the seat (61). The delivery fitting (71) is configured to close the seat (61) and to hold the suction valve (5) in position.

The delivery fitting (71) comprises an attachment means to a fluid supply conduit. In the pump according to the present invention, the delivery fitting (71), removably connected to the seat (61), also performs a plug or cover function for the delivery valve (7). Access to the delivery valve (7) itself is therefore very easy, only requiring the removal of the delivery fitting (71).

In the embodiment represented, which is preferred but not exclusive, the seat (61) of the delivery opening (6) comprises a bottom wall (62) in contact with which the delivery valve (7) is arranged. The bottom wall (62) is substantially defined by a shoulder of the delivery opening (6), arranged transversally to the longitudinal axis (Z) of the delivery opening (6). At an opposite end to the bottom wall (62), the seat (61) is open towards the outside and is provided with a coupling means to the delivery fitting (71). Such coupling means preferably comprises a thread. A sealing means is interposed, in a known way in the sector, between the delivery fitting (71) and the seat (61) and between the delivery fitting (61) and the delivery valve (7). When the delivery fitting (71) is connected to the seat (61), the delivery valve (7) is kept in position inside the seat (61).

The head according to the present invention is substantially suitable to be used in any volumetric pump.

A volumetric pump comprises a motor shaft (S) rotating about a main axis (X) . In a known way, the motor shaft can be connected to an activation motor for rotation about the main axis (X). The motor shaft (S) is supported by a body (10) of the pump, through a rotatable means, e.g. ball bearings.

The motor shaft (S) comprises at least one eccentric portion (E), contained within the body (10). The pump comprises at least one pumping element (2), which can be activated in a known way for performing a work cycle that comprises at least one fluid suction step and at least one fluid delivery step. The pumping element (2) is movable with respect to the pumping chamber (3) so as to vary the volume thereof for performing the suction and delivery steps.

The pumping element (2) is for example in the form of a piston, as in the embodiment shown. In other embodiments, which are not shown, the pumping element could be in the form of a membrane or a rotating lobed element, or another form known in the sector of volumetric pumps. The activation of the pumping element (2) takes place by the motor shaft (S). The pumping element (2) is preferably connected, in a known way, to the eccentric portion (E) of the motor shaft (S), by means of a rotatable coupling about an axis (XI) parallel to the main axis (X). In particular, the pumping element (2) comprises a foot (22), connected to the eccentric portion (E) rotatably about the axis (XI) parallel to the main axis (X). In turn, the foot (22) is connected to a head portion (21) about a further axis of rotation (X2) parallel to the main axis (X).

It would also be possible to provide two or more pumping elements, connected to the motor shaft (S), in a known way, with distribution in a line, star or V arrangement. In this case the motor shaft (S) would be provided with a suitable number of eccentric portions.

The head according to the present invention is associated with the body (10) of the pump so that the pumping element (2) is movable at least in part within the pumping chamber (3), sealingly, for performing the suction and delivery steps.

In the embodiment represented, which is preferred but not exclusive, the pump comprises at least one piston (2), movable along a sliding direction (Y) in opposite directions for a suction stroke and a delivery stroke. The sliding direction (Y) is perpendicular to the main axis (X) .

At least one head portion (21) of the piston (2) is movable sealingly within the pumping chamber (3) along the suction and delivery strokes. In particular, the piston (2) is movable along a seat concentric to the sliding direction (Y) . In a known way, such seat is provided with an annular gasket (23), placed in contact with the lateral surface of the piston (2) which substantially limits or blocks leaks of fluid along the surface of the piston (2). Thanks to the head according to the present invention, access to the suction (5) and delivery (7) valves is very simple and quick, as it simply requires the removal of the suction (5) and delivery (7) fittings. The removal of both fittings (5,7) does not require the dismounting of the head, or the removal of the latter from the pump. Furthermore, it is not even necessary to predispose any further removal plugs or covers for access to the valves (5,7) themselves.

Claims

1) A head for a volumetric pump, comprising: a main body (1); a pumping chamber (3); a suction opening (4), placed in communication with the pumping chamber (3) and configured to place the pumping chamber (3) in communication with an external environment; a suction valve (5) arranged along the suction conduit to only enable flow directed towards the pumping chamber (3). a delivery opening (6), placed in communication with the pumping chamber (3) and configured to place the pumping chamber (3) in communication with an external environment; a delivery valve (7) is arranged along the delivery conduit (6) to only enable flow coming from the pumping chamber (3); characterised in that: the suction opening (4) is provided with a seat (41), inside which the suction valve (5) is housed, and a suction fitting (51), removably associated with the seat (41) and configured to retain the suction valve (5) in position in the seat (41) the delivery opening (6) is provided with a seat (61), inside which the delivery valve (7) is housed, and a delivery fitting (71), removably associated with the seat (61) and configured to retain the suction valve (5) in position in the seat (61).

2) The head according to claim 1 wherein: the seat (41) of the suction opening (4) comprises a bottom wall (42) in contact with which the suction valve (5) is arranged; at an opposite end of the bottom wall (42), the seat (41) is open towards the outside and is provided with a coupling means to the suction fitting (51).

3) The head according to claim 1 wherein: the seat (61) of the delivery opening (6) comprises a bottom wall (62) in contact with which the delivery valve (7) is arranged; at an opposite end of the bottom wall (62), the seat (61) is open towards the outside and is provided with a coupling means to the delivery fitting (71).

4) The head according to claim 1, wherein: the suction opening (4) is afforded within the main body (1) concentrically to a longitudinal axis (Z); the delivery opening (6) is afforded within the main body (1) concentrically to a longitudinal axis (Z) aligned with the longitudinal axis (Z) of the suction opening (4).

5) A volumetric pump comprising: at least one pumping element (2), which can be activated for performing a work cycle that comprises at least one fluid suction step and at least one fluid delivery step; a head (1) according to one of the previous claims, associated with a body (10) of the pump; wherein the pumping element (2) is movable with respect to the pumping chamber (3) so as to vary the volume thereof for performing the suction and delivery steps.

6) The volumetric pump according to claim 5, wherein the pumping element (2) comprises a piston, movable along a sliding direction (Y) in opposite directions for a suction stroke and a delivery stroke, wherein at least one head portion (21) of the piston (2) is sealingly movable within the pumping chamber (3) along the suction and delivery strokes.

7) The volumetric pump according to claim 5, wherein, in particular, the piston (2) is movable along a seat concentric to the sliding direction (Y), and wherein such seat is provided with an annular gasket (23), placed in contact with the lateral surface of the piston (2) to limit or block leaks of fluid along the surface of the piston (2).