The invention generally relates to a pressure chamber type diaphragm valve for opening / closing a fluid passage such as water or gas or controlling a flow rate or pressure and in particular to self-cleaning pressure chamber type diaphragm valve.

Background of the Invention:
A pressure chamber type diaphragm valve is used for opening / closing a fluid passage such as water or gas or controlling a flow rate or pressure. The pressure chamber type diaphragm valve may be operated purely on basis of pressure, in which case it is traditionally referred to as an entire pressure chamber type diaphragm valve. Alternatively, the pressure chamber type diaphragm valve may be operated on basis of a solenoid mechanism, in which case it is traditionally referred to as a solenoid based pressure chamber type diaphragm valve.

One of the typical common place uses of the solenoid based pressure chamber type diaphragm valve is in the form of water solenoid valve which is used extensively in washing machines, dish washers, water purifiers and similar products to switches ON/OFF water intake from supply line.

Figure 1 is a diagram showing a conventional entire pressure chamber diaphragm valve that comprises a valve body (1), an inlet (2), an outlet (3) and a valve seat (4) located in a flow path (5) between the inlet (2) and the outlet (3). A diaphragm valve (6) is located on the valve seat (4). The diaphragm valve (6) includes a diaphragm 7 and a diaphragm receiver (9). The diaphragm valve (6) is fixed to the valve body 1 vide an outer periphery portion (8) of the diaphragm (7). The diaphragm valve (6) together with the valve body (1) defines a chamber (10). The diaphragm receiver (9) is provided with a bleed hole (11) which establishes path between the inlet (2) and the chamber (10). The diaphragm receiver (9) is further provided with a central hole (12) which establishes path between the chamber (10) and the outlet (3). A pilot hole (13) is provided in the chamber (10). Opening / closing of the pilot hole (13) by an opening / closing means (14) opens / closes the flow path (5). In particular, when the opening / closing means (14) closes the pilot hole (13), the inlet water pressure (P1) is guided to the chamber (10) through the bleed hole (11), thereby bringing the pressure in the chamber (P2) to a value which is greater than the inlet water pressure (P1). Hence, the diaphragm valve (6) is pressed against the valve seat (4) by the pressure in the chamber (10) thereby closing the flow path (5). On the other hand, when the opening / closing means (14) opens the pilot hole (13), the chamber (10) communicates with the outflow port 3, so that the pressure in the chamber (10) (P2) decreases and reaches a value which is less than the inlet water pressure (P1). In this condition, the diaphragm valve (6) is pushed up by the inlet water pressure (P1) and separates from the valve seat (4) thereby opening the flow path (5).

Figure 2 is a diagram showing a conventional solenoid based pressure chamber type diaphragm valve that comprises a valve body (21), an inlet (22), an outlet (23) and a valve seat (24) located in a flow path (25) between the inlet (22) and the outlet (23). A diaphragm valve (26) is located on the valve seat (24). The diaphragm valve (26) includes a diaphragm (27) and a diaphragm receiver (29). The diaphragm valve (26) is fixed to the valve body (21) vide an outer periphery portion (28) of the diaphragm (27). The diaphragm valve (26) together with the valve body (21) defines a chamber (30). The diaphragm receiver (29) is provided with a bleed hole (31) which establishes path between the inlet (22) and the chamber (30). The diaphragm receiver (29) is further provided with a central hole (32) which establishes path between the chamber (30) and the outlet (23). There is further provided a solenoid mechanism (33) which interacts with the central hole (32) to open / close the flow path (25). In particular, the solenoid mechanism (33) comprises a plunger (34) which exhibits to-and-fro movement with respect to the central hole (32). The plunger (34) is provided with a sealing element (35) which selectively seals the central hole (32). The solenoid mechanism (33) further comprises a resilient member (36) which exerts force on the plunger in a direction towards the central hole (32), thereby causing the central hole (32) to be sealed by the sealing element (35). The solenoid mechanism (33) further comprises an electromagnetic coil (37) which in response to receiving an AC/DC electrical signal causes the plunger to move away from the central hole (32). Thus, when the electromagnetic coil (37) which in response to receiving an AC/DC electrical signal, the central hole (32) is not sealed by the sealing element (35).

When the central hole (32) is sealed by the sealing element (35), the inlet water pressure (P1) is guided to the chamber (10) through the bleed hole (31), thereby bringing the pressure in the chamber (P2) to a value which is greater than the inlet water pressure (P1). Hence, the diaphragm valve (26) is pressed against the valve seat (24) by the pressure in the chamber (30) thereby closing the flow path (25). On the other hand, when the central hole (32) is not sealed by the sealing element (35), the chamber (30) communicates with the outflow port (23), so that the pressure in the chamber (30) (P2) decreases and reaches a value which is less than the inlet water pressure (P1). In this condition, the diaphragm valve (26) is pushed up by the inlet water pressure (P1) and separates from the valve seat (24) thereby opening the flow path (25).

It has been observed that over the time, the bleed hole (11 or 31) is blocked by accumulation of dirt particles or sludge or scaling or foreign particles. Due to the accumulation of the dirt particles or sludge or scaling on the bleed hole or foreign particles, the inlet water pressure (P1) is not guided to the chamber (10 or 30). Thus, the inlet water pressure (P1) becomes greater than pressure in the chamber (P2) which in effect pushes the diaphragm (7 or 27) away from the valve seat (4 or 24), and more particularly, separates the diaphragm (7 or 27) from the valve seat (4 or 24). This causes failure in balancing pressure and hence undesired water flow between the inlet and the outlet.

Thus, there exists a need to provide a solution to address the aforesaid problem faced by accumulation of the dirt particles or sludge or scaling or foreign particles on the bleed hole.

Summary of the Invention:
This summary is provided to introduce a selection of concepts in a simplified format that is further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention nor is it intended for determining the scope of the invention.

In accordance with an embodiment, the present invention provides a diaphragm valve for use in a pressure chamber type diaphragm valve for opening / closing a fluid passage such as water or gas or controlling a flow rate or pressure. The diaphragm valve comprises a diaphragm and a diaphragm receiver. The diaphragm receiver defines a bleed hole. The diaphragm valve further comprises a self-cleaning mechanism co-operating with the bleed hole and removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole. In an embodiment of the invention, the self cleaning mechanism comprises a spring portion attached with a shaft portion, the shaft portion being adapted to traverse through the bleed hole thereby removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole.

The present invention further provides a solenoid based pressure chamber type diaphragm valve. The solenoid based pressure chamber type diaphragm valve, comprises a valve body; an inlet; an outlet; a valve seat located in a flow path between the inlet and the outlet; and a diaphragm valve located on the valve seat, the diaphragm valve comprises a diaphragm; a diaphragm receiver defining a bleed hole; and a self-cleaning mechanism co-operating with the bleed hole for removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole.

To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

Brief Description of the drawings:
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Figure 1 demonstrates a sectional view of a conventional entire pressure chamber diaphragm valve;
Figure 2 demonstrates a sectional view of a conventional solenoid based pressure chamber type diaphragm valve;
Figure 3 demonstrates an exploded perspective view of diaphragm valve in accordance with an embodiment of the invention;
Figure 4 demonstrates a sectional view of the diaphragm valve in accordance with an embodiment of the invention in OFF state;
Figure 5 demonstrates a sectional view of the diaphragm valve in accordance with an embodiment of the invention in ON state; and
Figure 6 demonstrates a sectional view of a solenoid based pressure chamber type diaphragm valve comprising the diaphragm valve in accordance with an embodiment of the invention.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The device and examples provided herein are illustrative only and not intended to be limiting.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Now referring to Figure 3, the present invention provides a diaphragm valve (100) for use in a pressure chamber type diaphragm valve (not shown) for opening / closing a fluid passage such as water or gas or controlling a flow rate or pressure. The diaphragm valve (100) comprises a diaphragm (102) and a diaphragm receiver (104). The diaphragm receiver (104) defines a bleed hole (106). The diaphragm valve (100) further comprises a self-cleaning mechanism (108) co-operating with the bleed hole (106) and removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (106).

In an embodiment of the invention, the self cleaning mechanism (108) comprises a spring portion (110) attached with a shaft portion (112), the shaft portion (112) being adapted to traverse through the bleed hole (106) thereby removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (106).

Now referring to Figures 4 and 5, the working of the self cleaning mechanism (108) would be explained. The spring portion (110) contacts the diaphragm receiver (104) and is an expanded state when the diaphragm valve (100) is closing the flow path (not shown) or in other words, when the diaphragm valve (100) is in OFF state. In this state, the shaft portion (112) traverses through the bleed hole (106) to a first extent, as specifically shown in Figure 4. On the other hand, when the diaphragm valve (100) is in comes to ON state (i.e. when the flow path is open), diaphragm receiver (104) compresses the spring portion (110). In response to the spring portion being compressed, the shaft portion (112) traverses through the bleed hole (106) to a second extent, which is greater than the first extent, as specifically shown in Figure 5. Thus, the shaft portion (112) exhibits a to-and-fro motion with respect to the bleed hole (106) when the diaphragm valve (100) changes its state i.e. from ON state to OFF state and vice-versa. The to-and-fro motion of the shaft portion (112) dislodges or removes any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (106). It may be noted that the shaft portion (112) never completely seals the bleed hole (106) and there is sufficient space between the shaft portion (112) and the bleed hole (106) for guiding the inlet water pressure (P1) to the chamber (10) during.

Now referring to Figure 6, there is illustrated a solenoid based pressure chamber type diaphragm valve (200) constructed in accordance with the teachings of the present invention. The solenoid based pressure chamber type diaphragm valve (200) a valve body (201), an inlet (202), an outlet (203) and a valve seat (204) located in a flow path (205) between the inlet (202) and the outlet (203). A diaphragm valve (206) is located on the valve seat (204). The diaphragm valve (206) includes a diaphragm (207) and a diaphragm receiver (209). The diaphragm valve (206) is fixed to the valve body (201) vide an outer periphery portion (208) of the diaphragm (207). The diaphragm valve (206) together with the valve body (201) defines a chamber (210). The diaphragm receiver (209) is provided with a bleed hole (211) which establishes path between the inlet (202) and the chamber (210). The diaphragm receiver (209) is further provided with a central hole (212) which establishes path between the chamber (210) and the outlet (203). There is further provided a solenoid mechanism (213) which interacts with the central hole (212) to open / close the flow path (205). In particular, the solenoid mechanism (213) comprises a plunger (214) which exhibits to-and-fro movement with respect to the central hole (212). The plunger (214) is provided with a sealing element (215) which selectively seals the central hole (212). The solenoid mechanism (213) further comprises a resilient member (216) which exerts force on the plunger in a direction towards the central hole (212), thereby causing the central hole (212) to be sealed by the sealing element (215). The solenoid mechanism (213) further comprises an electromagnetic coil (217) which in response to receiving an AC/DC electrical signal causes the plunger to move away from the central hole (212). Thus, when the electromagnetic coil (217) which in response to receiving an AC/DC electrical signal, the central hole (212) is not sealed by the sealing element (215).

The solenoid based pressure chamber type diaphragm valve (200) further comprises a self-cleaning mechanism (218) co-operating with the bleed hole (211) and removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (211). In an embodiment of the invention, the self cleaning mechanism (218) comprises a spring portion (219) attached with a shaft portion (220). The shaft portion (220) is adapted to traverse through the bleed hole (211) thereby removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole.

The self-cleaning mechanism (218) is located in the chamber (210) such that one end of the spring portion contacts the diaphragm receiver (104), the another end of the spring portion contacts the valve body (201), and the shaft portion traverses through the bleed hole (211).

It may be noted that while no figure has been provided illustrating an entire pressure chamber diaphragm valve comprising the self-cleaning mechanism, since the construction of the entire pressure chamber diaphragm valve is substantially similar to the solenoid based pressure chamber type diaphragm valve (200) in relation to the diaphragm, the diaphragm receiver, the bleed hole in the diaphragm receiver, and the formation of the chamber, an entire pressure chamber diaphragm valve can be made by incorporating the self-cleaning mechanism in the chamber such that one end of the spring portion contacts the diaphragm receiver, the another end of the spring portion contacts the valve body, and the shaft portion traverses through the bleed hole.

While certain present preferred embodiments of the invention have been illustrated and described herein, it is to be understood that the invention is not limited thereto. Clearly, the invention may be otherwise variously embodied, and practiced within the scope of the description.

WE CLAIM:

1.A diaphragm valve (100) for use in a pressure chamber type diaphragm valve, said diaphragm valve (100) comprising:
a diaphragm (102);
a diaphragm receiver (104) defining a bleed hole (106); and
a self-cleaning mechanism (108) co-operating with the bleed hole (106) for removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (106).

2. The diaphragm valve as claimed in claim 1, wherein the self cleaning mechanism (108) comprises a spring portion (110) attached with a shaft portion (112), the shaft portion (112) being adapted to traverse through the bleed hole (106) thereby removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (106).

3. The diaphragm valve as claimed in claim 2, wherein the spring portion (110) contacts the diaphragm receiver (104) and is an expanded state when the diaphragm valve (100) is in OFF state.

4. The diaphragm valve as claimed in claim 2, wherein the shaft portion (112) traverses through the bleed hole (106) to a first extent when the diaphragm valve (100) is in OFF state.

5. The diaphragm valve as claimed in claim 2, wherein the diaphragm receiver (104) compresses the spring portion (110) when the diaphragm valve (100) is in ON state.

6. The diaphragm valve as claimed in claim 2, wherein the shaft portion (112) traverses through the bleed hole (106) to a second extent, which is greater than the first extent, when the diaphragm valve (100) is in ON state.

7. The diaphragm valve as claimed in claim 2, wherein the shaft portion (112) exhibits a to-and-fro motion with respect to the bleed hole (106) when the diaphragm valve (100) changes its state from ON state to OFF state and vice-versa.

8. The diaphragm valve as claimed in claim 2, wherein there is provided a space between the shaft portion (112) and the bleed hole (106).

9. A pressure chamber type diaphragm valve (200), comprising:
a valve body (201);
an inlet (202);
an outlet (203);
a valve seat (204) located in a flow path (205) between the inlet (202) and the outlet (203); and
a diaphragm valve (206) located on the valve seat (204), the diaphragm valve (206) comprises:
a diaphragm (207);
a diaphragm receiver (209) defining a bleed hole (211); and
a self-cleaning mechanism (218) co-operating with the bleed hole (211) for removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole (211).

10. The pressure chamber type diaphragm valve as claimed in claim 9, wherein the self cleaning mechanism (218) comprises a spring portion (219) attached with a shaft portion (220), the shaft portion (220) being adapted to traverse through the bleed hole (211) thereby removing any dirt particles or sludge or scaling or foreign particles accumulated in the bleed hole.

11. The pressure chamber type diaphragm valve as claimed in claim 9, wherein the diaphragm valve (206) is fixed to the valve body (201) vide an outer periphery portion (208) of the diaphragm (207).

12. The pressure chamber type diaphragm valve as claimed in claim 9, wherein the diaphragm valve (206) together with the valve body (201) defines a chamber (210), and the bleed hole (211) establishes path between the inlet (202) and the chamber (210).

13. The pressure chamber type diaphragm valve as claimed in claim 12, wherein the self-cleaning mechanism (218) is located in the chamber (210) such that one end of the spring portion (219) contacts the diaphragm receiver (209), the another end of the spring portion (219) contacts the valve body (201), and the shaft portion (220) traverses through the bleed hole (211).

14. The pressure chamber type diaphragm valve as claimed in claim 12, wherein the diaphragm receiver (209) is further provided with a central hole (212) which establishes path between the chamber (210) and the outlet (203).

15. The pressure chamber type diaphragm valve as claimed in claim 14, wherein the pressure chamber type diaphragm valve is a solenoid based pressure chamber type diaphragm valve and comprises a solenoid mechanism (213) which interacts with the central hole (212) to open / close the flow path (205).

16. The pressure chamber type diaphragm valve as claimed in claim 15, wherein the solenoid mechanism (213) comprises:
a plunger (214) which exhibits to-and-fro movement with respect to the central hole (212), that the plunger (214) being provided with a sealing element (215) which selectively seals the central hole (212);
a resilient member (216) which exerts force on the plunger in a direction towards the central hole (212), thereby causing the central hole (212) to be sealed by the sealing element (215); and
an electromagnetic coil (217) which in response to receiving an AC/DC electrical signal causes the plunger to move away from the central hole (212).