This invention relates to taps and is primarily concerned with adaptors for taps for use in a variety of environments from public washrooms to private homes.
One problem with taps in public washrooms is that if a conventional tap is used which can be turned, on by turning the tap handle, the tap can be left on resulting in wastage of water. Attempts to solve this problem have been suggested in which a tap has to be pushed down in order to open it but the problem with this arrangement is that it is difficult to wash one's hands if one hand has to be used to hold down the tap in order to keep it open. Further, such pressed-down taps tend to become clogged with lime scale and like deposits so that, in time, only a very little amount of water flows when the tap is pressed down. Eventually, the tap can be held in the pressed down position so that water flows continuously or, in the alternative, the tap becomes so stiff that it cannot be pushed down at all.
Various delay means have been suggested in order to avoid the necessity of holding the tap down in order to keep it open while, at the same time, limiting the time in which the tap is on in order to prevent or at least limit the wastage of water. In one suggestion, an adaptor for a tap was provided which had an insert body having a central bore in which was located an actuator rod which opened the tap when depressed and which was biased to a closed position by a spring.
Return movement of the actuator rod to the closed position under the action of the spring was delayed by a piston movable in a chamber and connected to the actuator rod. A ring on the piston engaged the walls of the chamber and the frictional effect of this engagement delayed return of the actuator rod to the closed position. A major disadvantage of this arrangement is that the ring is susceptible to wear calling for frequent replacement if the delaying action was to function effectively.
In another suggestion, an actuator rod was again displaced by a pressing action to open a tap against the action of a spring which urged the actuator rod towards the closed position. In this case, return movement of the actuator rod was delayed by the engagement of a resilient ring on the actuator rod but, again, the ring was susceptible to wear so that frequent replacement is necessary if the delaying action is to function effectively.
The disadvantages of the existing taps were overcome by the applicant's earlier invention, as detailed in GB 2289933 by providing an adaptor for a tap which can be turned on and which allows water to flow with hands off operation for only a limited period of time and which avoids the use of friction rings and thereby avoids the need for frequent replacement.
However, in these days of increased water shortages tap manufacturers not only face the problem, that of the wasting of water they also face a demand from users to limit water to the amounts required for individual jobs. For example, at home, the water required to wet a toothbrush prior to use is sufficiently less than that required to wash one's hands. Therefore, it is desirable to have a one-push tap, which provides a predetermined amount of water, as described above, which can operate in two or more modes in which the volume of water dispensed is different in each mode.
According to a first aspect of the present invention there is provided a tap adapter comprising a tap head, a tap body and a plunger, the plunger being slidably mounted within the body so as to be movable from a closed position to both a first open position and a second open position; resilient means being arranged to return the plunger from either open position to said closed position, the adapter being arranged such that the return to the closed position from said first and second open positions takes different lengths of time.
Preferably, the resilient means includes a first spring and a second spring, the second spring being arranged to counteract rotational movement of the plunger away from the closed position.
Preferably, the first open position lies in line with the closed position and the second open position is rotationally offset from the closed position.
Most preferably, the tap head and tap body have cooperating means which control the movement of the plunger between the closed and open positions.
In one embodiment there is a protrusion on the inside of the tap head and a channel in the wall of the tap body, such that movement of the plunger is only possible by moving the protrusion through said channel.
In said embodiment the channel comprises a first portion of a first length and a second portion positioned adjacent, but rotationally displaced from said first portion such that the protrusion can move from said first portion to said second portion in response to the rotation of the head.
Most preferably the first portion is shorter than the second portion and said first open position is achieved when the protrusion lies at the base of said first portion and the second open position is achieved when the protrusion lies at the bottom of said second portion.
Most preferably, the length of time required for the plunger to return from the first open position to the closed position lies in the range 5 to 8 seconds and the length of time required for the plunger to return from the second open position to the closed position lies in the range 10 to 360 seconds.
According to a second aspect of the present invention there is provided tap comprising a tap base, a tap head, a tap body and a plunger, the plunger being slidably mounted within the body so as to be movable from a closed position to both a first open position and a second open position; resilient means being arranged to return the plunger from either open position to said closed position, the adapter being arranged such that the return to the closed position from said first and second open positions takes different lengths of time.
An embodiment of the present invention will now be further described, by way of example, with reference to the drawings, wherein:—
Referring to the drawings, an adaptor for a tap, as detailed in
A control passage 7 of circular cross-section extends along the interior of the plunger 1. At one end of the passage 7 a cross-bore or aperture 9 of circular cross-section extends to the exterior of the plunger 1 and spaced therefrom and at the other end of the passage 7 two diametrically arranged and diametrically opposed apertures or holes 8 of circular cross-section extend into the chamber 14 at the exterior of the plunger 1.
Collars 10 and 11 formed on the exterior of the plunger 1 retain a circular cup seal 12 of V-shaped cross-section. The seal 12 forms on one of its sides one end of the chamber 13 within the body 2 and on its other side one end of the second chamber 14 formed within the body 2. The other end of the second chamber 14 is formed by a retaining cap 15 mounted on the body 2 and having apertures 16 for the passage of air. Between the collar 11 and a wall formed by an end or portion of the interior of the body 2 of reduced cross-section relative to the interior of the body 2 forming the chamber 13, there is arranged the spring means in the form of a coil spring 17.
A bore extends along the interior of the plunger 1 and one end of the bore forms the control passage 7. At the end of the plunger adjacent the spigot the bore is internally screw-threaded. A needle valve 6 has a screw-threaded boss 6A corresponding to the thread of the threaded portion of the bore. The needle valve is of metal or plastics material or may be moulded from plastics material with a tapered bore made during moulding. The needle valve 6 extends into the control passage 7 with the boss 6A engaging the internal screw-threading of the plunger 1. Rotation of the boss 6A causes the needle valve 6 to move along the bore of the plunger 1.
At the end of the plunger 1 remote from its end attached to the head 3 there is provided a tubular portion 18 of reduced cross-section relative to the parts of the plunger containing the needle valve 6. The tubular portion 18 has a frusto-conical collar 19 at one end thereof and a head 20 at the other end thereof, the collar 19 being provided with a rubber ring seal 21 and the head 20 being provided with a rubber ring seal 22. Surrounding the portion 18 is a cylindrical extension 23 projecting from the body 2.
As shown in
The adaptor for a tap as described above operates as follows:
1. Pushing plunger 1 down evacuates chamber 13 allowing air to pass seal 12 while allowing air into chamber 14 via aperture 16.
2. Upon release of the plunger the spring 17 forces the plunger up to create a low pressure resistance in chamber 13 maintained by seals 12 and 21 but allowing air to slowly leak through apertures 8 and aperture 9 via the adjustable tapered needle valve.
3. The time delay is created by adjusting the flow of air passing through the tapered needle valve from inlet aperture 8 to aperture 9.
4. The water flows in the direction of arrow X via outlet 30 in the direction of arrow Y. The water is shut off by seal 22 when plunger 1 is pushed back up.
As shown in
The tap can be thought of as a whole entity suitable for controlling the flow of a fluid. To this end the operation of the substantial part of the tap will operate as the prior art tap described previously herein. However, the tap can also be thought of as a tap base 51 and a tap adapter. The tap base would be coupled to the plumbing system in a house or public washroom and the tap adapter could be retrofitted thereto in order to upgrade an existing tap to use the adapter of the present invention. The tap base would be any tap base, designed to comply with appropriate national plumbing standards. The tap adapter, when in use, will be arranged to fit to any such tap base.
The tap adapter comprises a tap head 49, a tap body 50 and a plunger 38. The plunger 38 is slidably mounted within the body 50 so as to be movable from a closed position as illustrated in
Resilient means in the form of a first spring 40 and second spring 33 are arranged to return the plunger from either open position to the closed position.
As will become clear with a review of the adapter as illustrated in
As can be seen in more detail in
The length of time required for the plunger to return from the first open position to the closed position lies in the range 5 to 8 seconds. The length of time required for the plunger to return from the second open position to the closed position lies in the range 10 to 360 seconds.
The volume of water passed by the tap in each action is set both by the length of the first and second portions 56 & 58, by the tension of the spring and by the position of the restrictor 28 as illustrated in relation to the prior art tap, when adapted for use in the dual action tap described herein.
When in use a person wishing a short burst of water will strike the tap from above causing a downward movement of the tap head 49 and plunger 38 into said first open position, at the base of the first portion 56. If a user wishes a larger volume of water to be passed he or she will first rotate the head 49 and therefore the plunger 38 and thereafter urge the tap downwards into said second open position, at the base of the second portion 58.
Modifications can be incorporated without departing from the invention as claimed. For example, the invention also extends to taps fitted with the adaptor above-described.
Number | Date | Country | Kind |
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0615925.5 | Aug 2006 | GB | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/GB07/02961 | 8/3/2007 | WO | 00 | 2/9/2009 |