WO2006100656A1

WO2006100656A1 - A drain plunger

Info

Publication number: WO2006100656A1
Application number: PCT/IE2006/000016
Authority: WO
Inventors: Noel Flynn
Original assignee: HOUSE MOSQUITO Ltd
Current assignee: HOUSE MOSQUITO Ltd
Priority date: 2005-03-22
Filing date: 2006-03-22
Publication date: 2006-09-28
Anticipated expiration: 2007-09-22
Also published as: IES20060225A2; IE20060226A1

Abstract

A drain plunger (1) comprises a handle (2), a suction cup (6), a valve (17) configured to open on an upward stroke such that the suction cup (6) applies less pressure in an upward stroke than in a downward stroke, said valve being located within the handle (2), and a vent (5) to atmosphere for the valve. The valve (17) opens automatically by virtue of suction within the cup (6) during the upward stroke. The handle comprises a chamber (4) having the vent (5), the chamber being configured to receive and retain liquid during the downward stroke when the valve is closed, the valve being located below the chamber. There is a reservoir (10) for unblocking agent, and a blade (15) for opening the reservoir automatically by pushing action on the handle in a downward stroke. The blade (15) is formed by an upper extremity of a piston (7) which is movable axially within the handle and which comprises an outlet (18) at its lower extremity. The piston (7) comprises a side opening (21) for venting the valve (17) to atmosphere and for flow of unblocking agent into the chamber (4) during a downward stroke, the side opening (21) allowing flow of unblocking agent from the chamber (4) to the outlet (18) of the piston during an upward stroke.

Description

"A Drain Plunger"

INTRODUCTION

Field of the Invention

The invention relates to plungers for freeing obstructions in drains, for example, in sink or shower drains.

Prior art Discussion

The conventional drain plunger comprises a handle and a suction cup, and is thus of simple construction. The user presses the cup onto the surface around a drain opening to obtain the best possible seal with its rim. The handle is pushed down, causing water to be pushed along the drain. The handle is then pulled, so that a vacuum is created within the suction cup, causing the water to be sucked towards the plunger.

US5927957 describes a plunger having a connection to a tap for application of water under pressure. US 2496525 describes a plunger having a flap valve in the deformable wall of the suction cup.

The invention is directed towards providing an improved plunger for more effective dislodgement of an obstruction in a drain.

SUMMARY OF INVENTION

According to the invention, there is provided a drain plunger comprising: a handle, a suction cup, a valve configured to open on an upward stroke such that the suction cup applies less pressure in an upward stroke than in a downward stroke, said valve being located within the handle, and a vent to atmosphere for the valve.

In one embodiment, the valve opens automatically by virtue of suction within the cup during the upward stroke.

In another embodiment, the handle comprises a chamber having said vent.

In a further embodiment, the chamber is configured to receive and retain liquid during the downward stroke when the valve is closed, the valve being located below the chamber.

In one embodiment, the valve is a rotatable valve.

In another embodiment, the plunger further comprises a reservoir for unblocking agent, and control means to allow flow of the agent into a drain.

hi a further embodiment, the control means allows flow of unblocking agent during an upward stroke when the valve is open.

In one embodiment, the control means comprises means for opening the reservoir automatically by pushing action on the handle in a downward stroke.

In another embodiment, the control means comprises a seal for the unblocking agent reservoir and a blade for cutting the seal during the pushing action.

In a further embodiment, the blade is formed by an upper extremity of a piston which is movable axially within the handle and which comprises an outlet at its lower extremity. In one embodiment, the piston comprises a side opening for venting the valve to atmosphere and for flow of unblocking agent into the chamber during a downward stroke, the side opening being located and configured to allow flow of unblocking agent from the chamber to the outlet of the piston during an upward stroke.

In another embodiment, the piston extends through the chamber.

In a further embodiment, the piston comprises stop members to limit upward and downward movement of the piston within the handle.

In one embodiment, the valve is within the piston.

In another embodiment, the handle is telescopic for compact storage.

In a further embodiment, the unblocking agent reservoir comprises a socket to receive a disposable unblocking agent cartridge.

Detailed Description of the Invention

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: -

Fig. 1 is a an elevational view of a plunger of the invention;

Figs. 2 to 6 inclusive are cross-sectional views showing the. plunger in use;

Figs. 7(a), 7(b), 7(c), and 7(d) are alternatively elevation and cross-sectional views showing a piston of the plunger in more detail; Figs. 8 and 9 are cross-sectional views of an alternative plunger; and

Figs. 10(a) and 10(b) are cross-sectional views of an alternative plunger handle.

Description of the Embodiments

Referring to Figs. 1 to 7 a drain plunger 1 of the invention is illustrated. The plunger 1 is of plastics moulded construction. It comprises a handle 2 with a threaded cap 3 for receiving a disposable cartridge 10 of unblocking agent. The cartridge 10 has a lower breakable seal 1 l.The handle 2 is integral with a chamber 4, which is in turn connected to a deformable suction cup 6.

The chamber 4 comprises a pair of opposed vents 5. A piston 7 moves within the chamber 4 in a vertical direction on a central axis of the plunger 1. Referring particularly to Figs. 7(a) to 7(d), the piston 7 comprises an upper tapered edge forming a blade 15, and it is of generally tubular construction. It also comprises a rotatable valve 17 in a lower section. The piston 7 slides within a sleeve 20 formed by a plastics moulding which is integral with the chamber 4 and the handle 2. The sleeve 20 is retained in fixed position by friction within a top through-hole 23 of the suction cup 6.

The piston 7 also comprises a collar 19 for preventing downward movement beyond a limit set by abutment of the collar and the upper edge of the sleeve 20. The piston also comprises a lower opening 18, and a side slot 21. Finally, the piston comprises a transverse pin 22 for preventing upward movement beyond a limit set by the pin 22 and the top of the chamber 4.

In operation, the user "fills" the plunger by inserting a full cartridge 10 into the handle 2 after removing the screw cap 3. The plunger 1 is now ready for use, as shown in Fig. 2. When a drain D, such as the drain of a sink, is blocked the plunger is placed over the drain hole in conventional manner for a plunger, with the cup contacting the drain hole rim. The plunger is then pushed down as shown in Fig. 3, causing downward pressure in the drain. This causes the piston 7, which can not move below the level of the drain hole, to cut the cartridge membrane 11 as the latter moves downwardly relative to it. This causes a downward flow under gravity of unblocking agent to flow from the cartridge 10 and down through the piston 7 and out the aperture 21 into the chamber 4 as indicated by the arrows L.

In the upward stroke, which follows immediately afterwards, the situation is as shown in Fig. 4. As the cup 6 begins to re-shape, suction is created within the cup 6. This suction pulls the water in the drain up, as shown by the letter P in Fig. 4. The suction also pulls open the valve 17, thereby drawing down the unblocking agent. The downward flow of unblocking agent and the suction below the cup 6 are easily able to maintain the valve 17 open, allowing all of the unblocking agent to flow freely through the opening 18.

The user leaves the unblocking agent to take effect for about 20 minutes, or other duration depending on the nature of the unblocking agent. After this time the plunger 1 is pushed down in a stroke as shown in Fig. 5. The pressure of the water within the area encompassed by the cup 6 helps to keep the valve 17 closed, and so there is full downward pressure as for a conventional drain plunger.

The next upward stroke is shown in Fig. 6. In this stroke there is reduced upward suction pressure on the drain water because the suction opens the valve 17. This vents the space below the cup 6 to atmosphere via the valve 17, the slot 21, and the chamber vents 5. In the example of Fig. 6, the water in the sink surrounds the chamber 4, and there is a flow of water in the direction of the arrows Q down into the drain. Because of venting to the surrounding water or air, there is reduced suction on the upward stroke. Thus for repeated cycles of downward stroke followed by upward stroke there is a net greater pressure along the drain away from the drain hole. Thus, the plunger not only provides pushing and pulling action on the drain water, but it also automatically dispenses an unblocking agent. The fact that this is automatic is particularly effective.

Referring to Figs. 8 and 9 an alternative plunger, 50, comprises a handle which incorporates a reservoir 51 for unblocking agent. The handle 51 is connected to a cup 55 at an upper sleeve of the cup. A tear-band 52 prevents movement of the handle 51 relative to the cup 55 until use. The handle incorporates, within the cup sleeve, a valve 56, a blade 57, a membrane seal 58 for unblocking agent, and vents 59.

In operation, the user tears away the band 52 and pushes the plunger against a drain hole, causing the blade 57 to move relative to the membrane 58, to thereby break the membrane 58.The unblocking agent then flows out through the valve 56 as shown in Fig. 8 and operation of the plunger 50 is in general as described above for the plunger 1.

As shown in Figs. 10(a) and 10(b) the plunger of the invention may incorporate a telescopic handle 70 having mutually sliding parts 71 and 72 which interlock with a bayonet-type connector 74 at extended and retracted positions. This allows it to be more compact for transport and storage. The handle 71 also incorporates a slot 73 to enable easier extraction of the cartridge.

It will be appreciated that the invention provides a drain plunger which is particularly effective because it automatically dispenses unblocking agent in a manner whereby it is drawn quickly and comprehensively down into the drain towards the obstruction. It is also particularly effective because it applies a net downward pressure, helping to move the obstruction along the drain. To achieve this, the user does not need to operate the plunger in a manner differently from a conventional plunger, other than to insert the unblocking agent cartridge. Also, the plunger may operate without a depth of water, such as in a shower tray, because venting to air achieves the benefit of reduced pressure being applied on the upward stroke.

The invention is not limited to the embodiments described but may be varied in construction and detail.

Claims

1. A drain plunger comprising:

a handle (2),

a suction cup (6),

a valve (17) configured to open on an upward stroke such that the suction cup (6) applies less pressure in an upward stroke than in a downward stroke, said valve being located within the handle (2), and

a vent (5) to atmosphere for the valve.

2. A drain plunger as claimed in claim 1, wherein the valve (17) opens automatically by virtue of suction within the cup (6) during the upward stroke.

3. A drain plunger as claimed in claims 1 or 2, wherein the handle comprises a chamber (4) having said vent (5).

4. A drain plunger as claimed in claim 3, wherein the chamber (4) is configured to receive and retain liquid during the downward stroke when the valve is closed, the valve being located below the chamber.

5. A drain plunger as claimed in any preceding claim, wherein the valve is a rotatable valve (17).

6. A drain plunger as claimed in any preceding claim, further comprising a reservoir (10) for unblocking agent, and control means (11, 15) to allow flow of the agent . into a drain.

7. A drain plunger as claimed in claim. 6, wherein the control means (11, 15) allows flow of unblocking agent during an upward stroke when the valve is open.

8. A drain plunger as claimed in claims 6 or 7, wherein the control means comprises means (15) for opening the reservoir automatically by pushing action on the handle in a downward stroke.

9. A drain plunger as claimed in claim 8, wherein the control means comprises a seal (11) for the unblocking agent reservoir (10) and a blade (15) for cutting the seal during the pushing action.

10. A drain plunger as claimed in claim 9, wherein the blade (15) is formed by an upper extremity of a piston (7) which is movable axially within the handle and which comprises an outlet (18) at its lower extremity.

11. A drain plunger as claimed in claim 10, wherein the piston (7) comprises a side opening (21) for venting the valve (17) to atmosphere and for flow of unblocking agent into the chamber (4) during a downward stroke, the side opening (21) being located and configured to allow flow of unblocking agent from the chamber (4) to the outlet (18) of the piston during an upward stroke.

12. A drain plunger as claimed in any of claims 3 to 11, wherein the piston (7) extends through the chamber (4).

13. A drain plunger as claimed in any of claims 10 to 12, wherein the piston (7) comprises stop members (19, 22) to limit upward and downward movement of the piston (7) within the handle (2).

14. A drain plunger as claimed in any of claims 10 to 13, wherein the valve (17) is within the piston (7).

15. A drain plunger as claimed in any preceding claim, wherein the handle (70) is telescopic for compact storage.

16. A drain plunger as claimed in any of claims 6 to 15, wherein the unblocking agent reservoir comprises a socket to receive a disposable unblocking agent cartridge (10).