NZ580924A - A water pump having a check valve - Google Patents

Abstract

A water pump having a check valve is disclosed. The water pump comprises a power casing having a motor mounted therein, a water casing attached to the power casing, an impeller, a pressure tank, a check valve, and a reed switch. The water casing comprises an outlet connector, an outlet tube connected to the outlet connector, and a supplementary tube. The impeller is mounted rotatably within the water casing and is connected to and driven by the motor. The pressure tank is connected to the water casing and the check valve is mounted in the outlet connector. The check valve comprises a washer adapted to mount around an annular flange of the outlet connector, a gasket attached to the washer, a piston rod mounted through the washer and gasket and having a rod body protruding through the washer and the gasket, a collar formed around an end of the rod body, and a cavity defined between rod body and the collar. The check valve also includes at least one magnet mounted in the cavity of the piston rod, a pad mounted around the rod body and abutting the collar, a guiding seat mounted around the rod body, and a spring mounted around the pad and mounted between the guiding seat and the collar. The reed switch is mounted in the water pump to be selectively switched on or off by the at least one magnet.

Description

P580924 Received at IPONZ 12/08/2010 NEW ZEALAND PATENTS ACT, 1953 No: Date: COMPLETE SPECIFICATION CHECK VALVE AND A WATER PUMP WITH THE SAME We, WALRUS PUMP CO., LTD., a Taiwanese company of 83-14, Da Pian Tou, Ho Chuoh Village, San Chi, Taipei Hsien, Taiwan, Republic of China, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: (followed by page la) 3Q10/225590SL1.DOC P580924 Received at IPONZ 12/08/2010 la (followed by page lb) CHECK VALVE AND A WATER PUMP WITH THE SAME 1. Field of the Invention The present invention relates to a check valve, especially to a check valve for a water pump with long lifespan. 2. Description of the Prior Arts Water pumps pressurize water to deliver the water to desired places, especially for delivering water from lower places to higher places. The conventional pump has a conventional check valve. The conventional check valve is connected to an outlet tube of the conventional pump to prevent 10 backflow to protect the impeller. The conventional check valve comprises a piston rod and a spring. When the impeller is operated to pressurize and deliver out the water, the piston rod is pushed to press the spring so that the water flows out of the outlet tube. When the impeller is not operated, the spring pushes the piston rod to move back to seal the outlet tube so that the backflow 15 does not stream back to cause the impeller damage.

However, when the piston rod is pushed by the pressurized water to press the spring, the pushing force is usually to large to over-press the spring. Therefore, the spring may be broken easily after long term over-pressing.

A preferred example of the present invention seeks to provide a water pump 20 comprising check valve to mitigate or obviate one or more of the aforementioned problems, or at least that seeks to provide the public with a useful choice.

The present invention provides a water pump comprising: a power casing having a motor mounted therein; a water casing attached to the power casing and comprising: 25 an outlet connector; 2464238 l.DOC P580924 Received at IPONZ 12/08/2010 lb (followed by page 2) an outlet tube connected to the outlet connector; and a supplementary tube; an impeller mounted rotatably in the water casing, connected to and driven by the 5 motor; a pressure tank connected to the water casing; a check valve mounted in the outlet connector and comprising: a washer mounted around an annular flange of the outlet connector; a gasket attached to the washer; a piston rod mounted through the washer and the gasket and comprising: a rod body protruding through the washer and the gasket; a collar formed around an end of the rod body; and a cavity defined between the rod body and the collar; at least one magnet mounted in the cavity of the piston rod; 15 a pad mounted around the rod body and abutting the collar; a guiding seat mounted around the rod body; and a spring mounted around the pad and mounted between the guiding seat and the collar; and a reed switch mounted in the water pump to be selectively switched on or off by the 20 at least one magnet.

The term "comprising" as used in this specification means "consisting at least in part of. When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same 25 manner.

There is described herein a check valve for a water pump. The check valve for a water pump has a guiding seat, a washer mounted in an inner end of an outlet connector, a gasket abutting the washer, a piston rod, a pad and a spring. The piston rod is movably to 2709998_l.doc P580924 Received at IPONZ 12/08/2010 2 selectively allow the water flow. The pad is attached to a collar of the piston rod. The spring is mounted around the pad and is mounted between the collar and the guiding seat. Therefore, the spring is not over-pressed since the pad stops the piston rod from moving when the pad is clamped between the collar 5 and the guiding seat.

The present invention will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which Fig. 1 is a front view in partial section of a water pump with a check valve in accordance with the present invention; Fig. 2 is a side view in partial section of the water pump in Fig. 1; Fig. 3 is an exploded perspective view of the check valve in Fig. 1 with an outlet connector; Fig. 4 is a perspective view of a guiding seat of the check valve in Fig. 3; Fig. 5 is another perspective view of the guiding seat in Fig. 4; Fig. 6 is a front view in partial section of the guiding seat in Fig. 4; Fig. 7 is a side view in partial section of a gasket of the check valve in Fig. 3; Fig. 8 is an operational front view in partial section of the check valve 20 in Fig. 3, shown sealing the outlet tube; Fig. 9 is an operational front view in partial section of the check valve in Fig. 3, shown opening the outlet tube; and Fig. 10 is an enlarged front view of the water pump in Fig. 1. 2464238J .DOC P580924 Received at IPONZ 12/08/2010 3 With reference to Figs. 1 and 2, a water pump with a check valve (10) in accordance with the present invention comprises an outlet tube (101), an outlet connector (101), a power casing (20), a water casing (30), an impeller (40) and a pressure tank (50).

With reference to Figs. 1, 3 and 4, the outlet connector (101) is formed on an end of the outlet tube (100) and has an outer end (102), an inner end (103), an annular flange (104) formed in the inner end (103) and multiple fastening holes (105).

The check valve (10) is mounted in the outlet connector (101) and 10 comprises a washer (11), a gasket (12), a piston rod (13), at least one magnet (14), a pad (15), a guiding seat (1 6) and a spring (17).

The washer (11) is mounted around the flange (104) and may be L-shaped in cross section.

With further reference to Fig. 8, the gasket (12) is attached to the 15 washer (11) and has an annular body (121) and multiple resilient elements (122). The resilient elements (122) are perpendicularly mounted separately in the annular body (121) and are leaned by an angle 0. The angle 0 may be 5 degrees.

The piston rod (13) is mounted through the washer (11) and the gasket 20 (12) and has a rod body (13 1), a collar (132), a cavity (133) and a protruding part (134). The rod body (131) protrudes through the washer (11) and the gasket (12). The collar (132) is formed around an end of the rod body (131). The cavity (133) is defined between rod body (131) and the collar (132). The protruding part (134) is formed around an outside wall of the collar (132) and 2464238 l.DOC P580924 4 Received at IPONZ 12/08/2010 abuts the washer (11) to selectively seal the inner end (103) of the outlet connector (101).

The at least one magnet (14) is mounted in the cavity (133) of the piston rod (13) and is secured and sealed by a glue layer (141). The glue layer 5 (141) may be flushed with an end of the collar (132). The magnet (14) may correspond to a reed switch to selectively switch on or off the reed switch.

The pad (15) is mounted around the rod body (131), abuts the collar (13 2) and may abut the glue layer (141).

With further reference to Figs. 5 to 7, the guiding seat (16) is mounted 10 around the rod body (131) and has a body (161), a through hole (162), two positioning protrusions (163), two fastening holes (164), two guiding protrusions (165) and multiple notches (166). The through hole (162) is formed through the body (161) and is mounted around the rod body (131). The positioning protrusions (163) are formed oppositely on an annular edge of the 15 body (161). The fastening holes (164) are formed respectively through the positioning protrusions (163) and respectively align with fastening holes (105) of the outlet connector (101). The guiding protrusions (165) are formed oppositely on the annular edge of the body (161) and are respectively located between the positioning protrusions (163). The notches (166) are formed 20 respectively in bottoms of the positioning and guiding protrusions (163, 165).

The spring (17) is mounted around the pad (15) and is mounted between the guiding seat (16) and the collar (132). An end of the spring (17) may be secured in the notches (166) of the guiding seat (16).

With reference to Fig. 2, the power casing (20) has a motor (21) P580924 Received at IPONZ 12/08/2010 mounted therein. The water casing (30) is attached to the power casing (20) and has a supplementary tube (302). The impeller (40) is mounted rotatably in the water casing (30) and is connected to and is driven by the motor (21).

With reference to Figs. 1, 2 and 10, the pressure tank (50) is connected to the water casing (30) and has a base (51), a cover (52), a receiving seat (53), a diaphragm, a pressing seat (55), a spring (56), a plug (57), an adjusting screw (58) and a box (59). The base (51) is connected to the supplementary tube (302) of the water casing (30) via a connecting tube (51 1). The cover (52) is mounted detachably on the base (5 1) to define a cavity between the base (5 1) and the cover (52). The receiving seat (53) and the pressing seat (55) are mounted in the cavity of the pressure tank and are attached securely to the base (51). The diaphragm is mounted between the receiving seat (53) and the pressing seat (55). The spring (56) is mounted in the cavity of the pressure tank and presses against the pressing seat (55). The plug (57) is mounted in the spring (56) and presses against the spring (56). The adjusting screw (58) is mounted through the plug (57) and is mounted through the cover (52). When the adjusting screw (58) is rotated, the position of the plug (57) is adjusted to press or release the spring (56). The clamping force between the receiving seat (53) and the pressing seat (55) is adjusted by the spring (56). Therefore, the user easily adjusts the pressure to the diaphragm. The box (59) is attached outside the pressure tank (50) to contain the circuit board and has a detachable lid (591) so that the circuit board is repaired easily.

With further reference to Fig. 9, when the motor (21) is operated to rotate the impeller (40), the water in the water casing (30) is pressurized and 246423S_1.DOC P580924 6 Received at IPONZ 12/08/2010 flows through the outlet tube (100). The pressurized water pushes the piston rod (13) to move upward so that the water flows out of the water pump.

The present invention has following advantages. Because the spring (17) is mounted around the pad (15), the pad (15) stops the piston rod (13) from 5 moving when the glue layer (141) and the guiding seat (16) clamp the pad (15). Therefore, the spring (17) is not over-pressed since the pad (15) has a certain height. Thus, the life-span of the check valve (10) as described is prolonged.

Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details 10 of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

P580924 Received at IPONZ 12/08/2010

Claims (9)

Claims:

1. A water pump comprising: a power casing having a motor mounted therein; 5 a water casing attached to the power casing and comprising: an outlet connector; an outlet tube connected to the oudet connector; and a supplementary tube; an impeller mounted rotatably in the water casing, connected to and driven by the 10 motor; a pressure tank connected to the water casing; a check valve mounted in the oudet connector and comprising: a washer mounted around an annular flange of the outlet connector; a gasket attached to the washer; 15 a piston rod mounted through the washer and the gasket and comprising: a rod body protruding through the washer and the gasket; a collar formed around an end of the rod body; and a cavity defined between the rod body and the collar; at least one magnet mounted in the cavity of the piston rod; 20 a pad mounted around the rod body and abutting the collar; a guiding seat mounted around the rod body; and a spring mounted around the pad and mounted between the guiding seat and the collar; and a reed switch mounted in the water pump to be selectively switched on or off by the 25 at least one magnet.

2. The water pump as claimed in claim 1, wherein: the guiding seat of the check valve comprises: a body; 30 a through hole formed through the body and mounted around the rod body; two positioning protrusions formed oppositely on an annular edge of the body; 2688558-1 7 P580924 Received at IPONZ 12/08/2010 two guiding protrusions formed oppositely on the annular edge of the body and respectively located between the positioning protrusions; and multiple notches formed respectively in bottoms of the positioning and guiding protrusions; and 5 an end of the spring of the check valve is secured in the notches of the guiding seat.

3. The water pump as claimed in claim 1, wherein the piston rod of the check valve has a protruding part formed around an outside wall of the collar and abutting the washer adapted to selectively seal an inner end of the outlet connector. 10

4. The water pump as claimed in claim 2, wherein the piston rod of the check valve has a protruding part formed around an outside wall of the collar and abutting the washer adapted to selectively seal an inner end of the outlet connector. 15

5. The water pump as claimed in any one of-claims 1-4, wherein the check valve further comprises a glue layer formed in the cavity of the piston rod to secure and seal the at least one magnet.

6. The water pump as claimed in claim 5, wherein the glue layer of the check valve is 20 flushed with an end of the collar.

7. The water pump as claimed in claim 6, wherein the gasket of the check valve comprises: an annular body; and 25 multiple resilient elements perpendicularly mounted separately in the annular body and leaned by an angle

8. The water pump as claimed in claim 1, wherein the pressure tank comprises: a base connected to the supplementary tube of the water casing via a connecting 30 tube; a cover mounted detachably on the base to define a cavity between the base and the cover; 2688558-1 8 P580924 Received at IPONZ 12/08/2010 a receiving seat and a pressing seat mounted in the cavity and attached securely to the base; a diaphragm mounted between the receiving seat and the pressing seat; a spring mounted in the cavity and pressing against the pressing seat; a plug mounted in the spring and pressing against the spring; and an adjusting screw mounted through the plug and mounted through the cover.

9. A water pump being substantially as hereinbefore described with reference to the accompanying drawings. WALRUS PUMP CO.. LTD. By the authorised agents A J Park Per 2688558-1 9