GB1559819A - Liquid supply apparatus - Google Patents

Description

(54) LIQUID SUPPLY APPARATUS (71) We, AQUA-MARINE MANUFACTUR ING LIMITED, a company organized and existing under the laws of Ontario, Canada, of 36 Vine Avenue, Toronto 165, Ontario, Canada, 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: - This invention relates generally to liquid supply apparatus, particularly though not exclusively to self-contained liquid supply apparatus such as those which are utilized in boats, trailers, and living quarters located in isolated areas.

The present invention provides a liquid supply apparatus including a pump for pumping liquid from a liquid reservoir to a faucet, an electric motor operatively connected to said pump, conduit means for connection of the apparatus to a source of liquid under pressure, a valve having at least three outlets and connected (a) to said source conduit means, (b) to said faucet and (c) to said reservoir; such that in a first position of said valve said source conduit means is connected to the reservoir, in a second position of said valve said reservoir is connected to said faucet and in a third position of said valve said source conduit means is connected to said faucet, and an override switch for said electric motor operable by movement of said valve such that in said first and third positions said override switch is operative to deenergise said pump motor and in said second position said override switch permits said pump motor to be energised.

Thus for self-contained liquid supply apparatus such as those utilized in boats, trailers and the like, the owner of the vehicle is able to station it at a location where access may be had to a larger pres surized apparatus. Pressurized water outlets are often available in marinas, trailer parks, and so forth. In such instances, the owner of the vehicle is able to tie his vehicle supply apparatus directly into the pressurized outlet via said source conduit means and to be able to turn said faucet on without causing his vehicle pump motor to run. He may also fill the vehicle reservoir from the outside pressurized apparatus preferably utilizing at least part of the conduit running between the faucet and the reservoir, since this reduces the number of conduits or pipes required.However, the pump necessary to pump water from the reservoir to the tap when the vehicle is in isolation is located in that same line, and therefore it is desirable to incapacitate the pump during the time the reservoir is being filled from the outside pressurized system.

As preferred said source conduit means terminates adjacent said valve and the valve includes a masking portion movable therewith and adapted when the valve is in said second position to cover the termination of said conduit means for preventing ingress of dirt, grease and other contaminants.

Said valve preferably includes a rotatable cam for operating said override switch.

Said valve may include a rotatable valve member and the valve may have a fourth connection through a shut-off valve along a filling line to said reservoir to fill the same, and in which a line interconnecting the reservoir, the pump and said faucet resists liquid movement in the reverse direction from the pump to the reservoir when the pump is shut off.

As an alternative said valve may include as a valve member a sliding gate having two apertures therein and said source conduit means includes a one way check valve, said pump is connecteWto said three-way valve by way of a one-way check valve, and said three-way valve is connected to said reservoir by a filling line.

As preferred said faucet is arranged to control switch means for energising said pump motor such that when said faucet is closed, said pump motor is de-energised and when the faucet is opened said pump motor is energised. Said faucet may include a rotatable shaft for moving a valve member within a fluid passageway, and when said shaft is moved a small amount from said closed faucet position, said switch means is operative to energise the pump motor, either before or after the liquid passageway is partly opened. Said faucet may include a rotatable shaft for operating the faucet, said shaft being movable upon application of additional torque beyond a position in which the faucet is fully opened to a further position in which said switch means de-energises said pump motor.

A preferred embodiment of the invention will now be described with reference to the accompanying drawings, wherein: - Figure 1 is an exploded perspective view of a faucet for use in the liquid supply apparatus of this invention; Figure 2 is an axial sectional view of a shaft member of the faucet of Figure 1; Figures 3-6 are schematic views of some of the components of the faucet of Figure 1, showing sequential positions in the operation thereof; Figure 7 is a schematic view of the liquid supply apparatus of this invention; Figures 8, 9 and 10 are schematic views of a suitable valve for use in the apparatus of Figure 7.

In Figure 1 there is shown a faucet or a tap assembly 10 which is seen to include a tubular member 12 having a gate-type closure which includes a transverse integral rectangular channel 14 in which the gate (not seen in the Figure) reciprocates. The gate has an opening therethrough, and is adapted to move between a first position in which the opening is aligned with the central bore of the tubular member 12, and another position in which it is out of alignment with the bore, the gate thus closing the bore in the same manner as a valve.

The gate is caused to reciprocate between its two extreme positions by the rotation of a shaft 16 to which is connected a sprocket (not visible) which cooperates with a toothed portion on the gate in the manner of a rack-and-pinion arrangement. As can be seen, the shaft 16 is keyed at 18, and this is for the purpose of permitting the shaft 16 to register in non-rotating relation ship with a cam and shaft member 20. As best seen in Figure 2, the cam and shaft member 20 has an internal bore 22, which includes an integral key 23 adapted to register with the keyway 18 of the shaft 16.

Thus, when the member 20 is assembled to the shaft 16, the two rotate together, without slipping. The member 20 includes a circular portion 24, an upstanding shaft 26, and a downwardly depending cam portion 28. At the top of the shaft 26 is a splined or toothed portion 30, for interlocking with a knob, or equivalent structure adapted to be grasped and turned by hand.

The circular portion 24 has around a part of its periphery a step 34 which covers only a portion of a complete circle, for example in the region of 240 . As can be seen, the step 34 ends at vertical walls 35, one of which is shown in broken lines behind the shaft 26 in Figure 1.

It is intended that the step 34 with the end walls 35 thereof cooperate with another component of the assembly, of which only a portion is shown in Figure 1 as an inwardly projecting rigid tooth member 37.

When assembled together, the tooth member 37 projects into the step 34 so that it comes into mechanical interference with the walls 35, thus providing two "stops", determining the maximum angular rotation of the cam and shaft member 20 with respect to other portions of the assembly.

The cam portion 28 is interrupted by an opening 38, which opens downwardly through the bottom rim of the cam portion 28.

As best seen in Figure 3, the cam portion 28 is substantially circular for the most part, but includes a region 40 of which the radius gradually decreases in the counter-clockwise direction from a location near the bottom of the cam portion 28 as seen in the Figure 3 representation, to a location at approximately the "2 o'clock" position.

Also forming part of the assembly of Figure 1 is a micro-switch 42 having a sensing member 44 projection therefrom.

In Figure 1 the micro-switch 42 would appear in its correct horizontal relationship to the other parts if seen from directly above, although the Figure itself shows the switch in exploded relationship somewhat vertically above its true location. When assembled together, the micro-switch 42 is located such that the sensing member 44 bears against the cam portion 28 in the manner shown in Figure 3.

Attention is now directed to the leftward end of the tubular member 12 in Figure 1, which is seen to include an internally threaded collar portion 46, from which upwardly extends an integral post 48 which is adapted to receive a coil spring 50 of which one end 51 is receivable between two upwardly extending integral, spaced apart jaws 52. The other end 54 of the spring 50 is adapted to be received in a downwardly opening slot (not visible in Figure 1) in the underside of a finger member 55 which has a rounded end with an opening 56 adapted to register with the post 48, and which has a pointed end 58 long enough to enter the opening 38 in the cam portion 28, when the cam and shaft member 20 is in an appropriate rotational orientation.

Before discussing the operation and advantages of the structure shown in Figure 1, it is appropriate to recall one of the disadvantages of the system disclosed in U.S.

Patent No. 3,700,002, touched on earlier in this specification. The system of the U.S. patent is arranged in such a way that if the tap is turned on only sufficiently to close the micro-switch (thus causing the pump to operate), but not sufficiently to open the valve, then the pump will continue to operate indefinitely without doing any useful work, and thus wasting electrical energy. Likewise, when the tap is turned off, it may be turned off only sufficiently to cut off the water flow without opening the micro-switch to cause the pump to shut off. The present invention eliminates this problem by positively biasing the tap to an off position after the tap has been moved close to the closed position, whereby a positive closure of the valve and shut-off of the pump are simultaneously assured. The way in which this is achieved will be explained subsequently.

Another problem associated with the system of U.S. Patent 3,700,002 has also been dealt with, and relates to the risk of getting an air-lock in the pump when the reservoir has been emptied. As previously explained, when the pump is not self-priming (for example a centrifugal pump), there is a serious risk that an air-lock will occur in the pump, because when the reservoir has been drained down to the location of the water outlet from the reservoir, air can enter the pipe running between the reservoir and the inlet of the pump. If the reservoir is subsequently filled without doing anything to remove the air-lock, the airlock will remain. In the system described in U.S. Patent 3,700,002, the problem is avoided by the provision of a master switch which overrides the tap-controlled switch, and is capable of turning off the pump.To purge an air-lock in the pump, the said master switch is operated to prevent the pump from running, and the tap is opened to permit water contained in the pipe between the outlet side of the pump and the tap to flow back through the pump and force the air-lock into the water reservoir.

The foregoing is a rather complex procedure and the invention disclosed herein is such as to simplify the air-lock purging procedure considerably.

Attention is now directed to Figures 3-6, with the help of which the operation of the assembly illustrated in Figures 1 and 2 will be further explained.

Firstly it is to be understood that the finger member 55, as seen from above, is biased in the clockwise direction by the spring 50, this having the effect of biasing the cam and shaft member 20 to its furthest counter-clockwise limit position, as determined by contact between the tooth member 37 and the furthermost wall 35 (in broken lines in Figure 1). It is assumed that Figure 3 of the drawings illustrates this furthest counter-clockwise limit position for the member 20, and the cam portion 28 which forms a part thereof. In the condition of Figure 3 it is also assumed that the finger member 55 is still exerting a residual clockwise pressure on the counter-clockwise edge of the opening 38, in order to keep the member 20 firmly pushed to its limit position.In this limit position, it will be seen that the sensing member 44 of the micro-switch 42 is extended to its "off" position, and it is to be understood that the micro-switch 42 controls the operation of a pump which is arranged to pump water from a tank or reservoir to the assembly 10 shown in Figure 1. It is also to be understood that the furthest counter-clockwise rotary position of the cam and shaft member 20 corresponds with the "off" position of the gate contained within the rectangular channel 14, thereby closing the through-bore in the tubular member 12, and in effect shutting the valve.

Before proceeding to Figure 4, it,should be pointed out that a spring member 60 is secured to the cam portion 28 at about the location shown. The spring member 60 projects angularly away from the surface of the cam portion 28, and has a purpose which will become clear subsequently in this specification.

Attention is now directed to Figure 4, which is similar to Figure 3, but shows the cam portion 28 (and of course the other associated parts of the member 20) after clockwise rotation through an angle of 80 or 90 . The rotation of the cam portion 28 has caused the finger member 55 to come out of the opening 38, and it can be seen in Figure 4 as simply resting in biased relation against the outer surface of the cam portion 28. During the rotation from the Figure 3 to the Figure 4 condition, the finger member 55 would continue to exert a counter-clockwise biasing pressure on the cam portion 28 up to the moment when it slips out of the opening 38. At that point, the biasing pressure on the cam portion 28 suddenly ceases.It will also be seen in Figure 4 that the sensing member 44 of the micro-switch 42 has been caused to "ride up" over the "hill" 62 in the surface of the cam portion 28, and now presses against a part of the surface of the cam portion 28 of a greater radius, thereby turning the micro-switch 42 on and causing the pump to operate. It will further be seen from the close spacing in Figure 3 between the "hill" 62 and the sensing member 44, that the micro-switch 42 is turned on (thus starting the pump) before the finger member 55 leaves the opening 38, i.e. before the counter-clockwise biasing pressure exerted on the cam portion 28 ceases. Another event also takes place before the counter-clockwise biasing pressure exerted on the cam portion 28 ceases, and this is the initiation of the opening of the gate forming part of the valve closure for the tubular member 12.Because of this arrangement, it does not matter whether the micro-switch 42 closes before the gate valve begins to open, or vice versa. The important thing is that, over the full rotational range during which the micro-switch 42 is switched and during which the gate valve begins to open, the finger member 55 exerts a counter-clockwise biasing pressure on the cam portion 28. It will thus be understood that, when the point is reached where the end of the finger member 55 is just emerging from the opening 38, the gate valve will be already partially open (only a minor amount of opening is sufficient), and the pump wil be running. As the cam portion 28 (and thus the member 20) is rotated further in the clockwise direction through the conditions shown in Figures 4 and 5, the gate valve will continue to open further, and the pump will remain on.In Figure 5, it can be seen that the spring member 60 has come around into contact with a corner of the microswitch 42. This constitutes in effect a limit or "stop" which is sensed by the person operating the tap, and which in effect determines the "full open" position of the tap. It will be seen that, as the cam portion 28 rotates through the Figure 4 position to that shown in Figure 5, the sensing member 44 of the micro-switch 42 remains depressed thus keeping the pump on. At the condition shown in Figure 5, the sensing member 44 is just adjacent the opening 38 which has been swung around almost a full 180 from the situation shown in Figure 3.The contact between the spring member 60 and the micro-switch 42 however, prevents the operator from rotating the cam portion 28 a few degrees further so that the sensing member 44 enters the opening 38, and thus shuts off the pump.

However, if the operator should apply positive clockwise rotational pressure to the knob 32 and thus to the - cam and shaft member 20, it will be possible to bend the spring 60 as shown in Figure 6 so that the sensing member 44 does enter the opening 38, thus shutting off the pump. The purpose of this capability of turning off the pump while the gate valve is fully open will be explained in a moment. First however it is instructive to trace the portions shown in Figures 3-5 as the tap is closed, i.e. as the cam portion 28 is rotated in the counter-clockwise direction from Figure 5 through Figure 4 to the shut-off position of Figure 3. To begin with, rotation from the Figure 5 to the Figure 4 orientation will merely progressively close off the gate valve, while the pump continues to run, thus supplying water to the tap.Shortly beyond the Figure 4 orientation, however (in the counter-clockwise direction), the pointed end of the finger member 55 will enter the opening 38 and will instantly exert a counter-clockwise biasing torque against the cam portion 28, thus quickly rotating the same in the counter-clockwise direction to the Figure 3 condition. Between the initial "grab" of the finger member 55 and the final ppsition shown in Figure 3, two events will take place. One is the opening of the micro-switch 42 and thus the shutting off of the pump, while the other is the complete closure and shutting off of the gate valve.It will thus be understood that the operator of the tap will find that the flow of water can be gradually reduced to a given minimum level by counter-clockwise rotation of the knob 32, but that once this minimum level is achieved the cam and shaft member 20 of the knob 32 are suddenly subjected to a closing torque due to the exertion of the finger member 55. As these portions rotate under the applied torque, the operator will see the trickle of water completely shut off and will (probably) hear the pump shut off as well.

In a case where, upon opening the tap, the switch closes before the valve begins to open, it will be understood that it will be impossible for the operator to "leave" the tap in a condition representing a point between these two events, i.e. a condition in which the valve is closed but the switch is still "on" with the motor running. This is due to the fact that the resilient biasing finger 55 exerts positive closure torque over the full range between the two events just mentioned.

Similarly, in the case of the reverse sequence for the switch and valve, it will again be impossible for the operator to "leave" the tap in a condition in which the switch is off and the motor not running, but the valve is still partly open. Again, this is due to the fact that the resilient biasing finger 55 exerts positive closure torque over this entire range.

Attention is once more directed to Figure 6. When the respective components are in the condition shown in Figure 6, the gate valve is fully open and the pump is off. This satisfies the two conditions necessary for purging an air-lock in the reverse direction through the pump. More specifically, the pump is off, thus no longer urging water in the direction from the reservoir to the tap, and the tap itself is open, thus permitting water located in the line between the tap and the pump to move backwardly through the pump and into the portion of the line between the reservoir and the pump, thus expelling the air-lock into the reservoir.

It will be understood that the specific components shown in Figures 3-6 could be arranged in such a way that the sensing member 44, instead of dropping into the opening 38, drops into an earlier depression or pocket, such as the pocket shown in broken lines by the numeral 63 in Figure 4.

Naturally, with the provision of an "earlier" pocket 63 for the sensing member 44, the spring member 60 would have to be relocated so as to contact the microswitch 42 earlier in the rotation of the cam portion 28.

It will also be understood that the spring member 60 would have to be located at a vertical level against the outer surface of cam portion 28 sufficient to clear the finger member 55. In other words, these two would have to be arranged so as to eliminate the risk of mechanical interference.

The present invention provides advantages in the situation arising when a boat docks at a marina or a trailer arrives at a camp ground. In either of these condiions, the trailer or boat owner usually will refill his water reservoir, and while at the dock or camp ground generally will take water directly from the city water supply rather from his own water reservoir. In conventional systems presently available, a number of adjustments have to be made by the boat or trailer owner depending upon whether he wants to go on city water, refill his reservoir tank, or take water from his reservoir tank. The present invention provides a much simpler system than is currently available for achieving these objectives, and the same is illustrated schematically in Figure 7.In Figure 7 a reservoir tank 66 is adapted to provide water to be pumped by pump 67 along a line 68 to a three-way valve which is shown schematically at 70. A line 72 carries pressurized city water through a connector 73, a one-way check valve 75, and a pressure reducing valve 76 (if needed). From the pressure reducing valve 26, the city water is carried to a second connection on the valve 70. A third connection leads to the taps on the boat or in the trailer, while a fourth connection connects through a shut-off valve 79 to a filling line 80 leading to the tank 66.

In certain applications the filling line 80 may not be required, but the operation which is described below will be seen to be independent of the presence of the filling line 80. The filling line 80 is provided where in-place systems include a tank and a pump and also include a one-way check-valve in the line 68 leading from the pump to the valve 70, in order to prevent flow in the reverse direction from the valve 70 to the tank 66. In such cases, the filling line 80 may be connected from the outlet of the valve 79 to a suitable filling aperture in the tank 66. However, where the check-valve is not present in the line 68, and where the pump 67 is a centrifugal pump through which water can flow in the reverse direction, there is no need for the filling line 80, and such need not be provided.

The valve 70 is shown three times in Figure 7, identified by the numerals 1, 2 and 3. These positions are associated with the following operational modes. In position number 1 of the valve 70, city water from the source line 72 passes either along line 68 through the pump 67 to fill the tank 66, or (if there is a one-way check-valve in the line 68 which prevents flow in the reverse direction) through the valve 79 and filling line 80 to the tank 66. In this mode, the connection to the taps is closed.

In position number 2 of the valve 70, water in the tank 66 can be pumped by the pump 67 directly to the taps in the boat or trailer, and the city water connection is closed. In position number 2, it will be understood that the valve 79 would be shut off in order to prevent short-circuiting of the water from the tank back along the filling line 80.

In position number 3, the city water is connected directly to the taps of the boat or trailer, and the connection to the pump 67 of the tank 66 is closed. Again in position number 3, it will be understood that the valve 79 will have to be closed to prevent water passing from the city water system to the filling aperture of the tank 66.

Where the line 80 is not provided (i.e.

where there is no check-valve in the line 68 and where the pump 67 is a centrifugal pump), the above modes may be read by ignoring the mention of the valve 79 of the filling line 80.

Advantageously a micro-switch 78 is provided at a fixed location with respect to the rotational axis of the valve 70, and the micro-switch 78 constitutes a master overriding control for the pump 67. For example the micro-switch 78 could be wired in series with the primary switch controlling the motor of the pump, i.e. the switch 42 shown in Figure 1.

The rotary element of the valve 70 has associated with it an outwardly projecting cam surface 81 which when aligned with the sensing element of the micro-switch 78 turns the latter on, which permits the pump 67 to be energized whenever the tap (discussed in relation to the earlier Figures) is turned on. The micro-switch 78 is turned on only in position number 2, where the flow of water is adapted to pass directly from the tank 66 through the pump 67 to the taps in the trailer or boat. In both of the other conditions, the overriding microswitch 78 is off, whereby the opening of one of the taps or valves discussed in connection with the earlier Figures will not energize pump 67 (since it is not needed in either case).

In a preferred embodiment of this invention, the valve 70 will be mounted in close association with the standard connector 73, and the rotary portion of the valve 70 will have an outwardly projecting finger or "mask" portion adapted to be situated in front of the connector 73 whenever the valve is in position number 2, namely the position where water to the taps is coming directly from the tank 66. This will prevent dirt and dust from entering the connector 73 under these circumstances. In the other two positions of the valve 70, of course, a hose from the city water eonnection would be coupled to the connector 21, thus - eliminating any problem of dirt or dust contamination in this respect.

Attention is now directed to Figures 8 10, which show schematically a valve construction which may be substituted for the valve 70 in Figure 7. These figures illustrate the operative portions of a valve which includes sliding gate 83 having two apertures 84 and 85 therethrough.

A line 86 from the pump leads through a check-valve 87 and can pass water directly-through to the line 89 whenever one of the apertures 84 and 85 is in alignment with these two lines. City water comes in through- a line 90 and through a checkvalve - 91 to - be directly connected to the line 89. Both of these are in full communication with a line 93 which goes to the taps in the boat or trailer A further line 95 is in- con'plete communication with the tap, the city water and the line 89, and leads up against the gate 83 so as-to be blocked thereby in certain of its positions. On the other side of the gate 83, the line 95 communicates through to a line 97 which passes to the filling opening of the tank.

In the particular position shown in Figure 8, the -opening 84 is interposed in alignment between the lines 86 and 89, such that water can be pumped directly from the tank to the taps. The water- cannot get out into the city water system due 'to the checkvalve' gl, and cannot recirculate back'to the tank fill due to the fact that there is no aperture allowing communication - between the lines 95 and 97. Thus Figure 8 represents the mode in which water from the tank can be pumped to the taps. This corres- ponds to the position number 2 in Figure 7, in which the microswitch 78 is "on" and allows energization of the pump 67.

In Figure 9 the gate 83 is in an intermediate position, in which neither of the openings 84 and 85 is interposed in any of the lines. Thus, water cannot be pumped from the tank along line 86, and water cannot be recirculated to fill the tank along line 97. However water from the city water system can pass through the check-valve 91 and along line 93 to the taps. Figure 9 corresponds to position 3 in Figure 7, in which the microswitch 78 is "off", preventing operation of the pump 67.

Figure 10 shows a condition in which the two apertures 84 and 85 are interposed against the lines 97 and 86, respectively. In this mode, water from the city water system under pressure can pass through the checkvalve 91 and along the filling line 97 to fill the tank. Water from the city water system could not pass along the line 86 due to the presence of the check-valve 87. At the same time in Figure 10, water from the city water system could pass out along line 93 to the taps, if these should be turned on.

Figure 10 corresponds to some extent to position 1 in Figure 7, and certainly in this mode the microswitch 78 would be turned "off", so that the accidental opening of one of the taps during the filling operation -would not call upon the pump 67 to pump against a closed gate.

Reference should be made to co-pending Patent application No. 41082/75 (Serial No. 1559817) from which the present application is divided and to co-pending Patent application No. 28575/78 (Serial No.

1559818) which is also divided from application No. 41082/75. Both these applica-- tions include claims to features of the apparatus described herein; WHAT WE- CLAIM IS:- 1. A liquid supply - apparatus including a pump for pumping liquid from a liquid reservoir to a faucet, an electric motor operatively connected to said pump, conduit means for connection of the apparatus to a source of liquid under pressure, a valve having at least three outlets and con-nected (a) to said source conduit means, (b) to said faucet and (c) to said reservoir; such that in a-first position of said valve said source conduit means is connected to the reservoir, in a second position of said valve said reservoir is connected to said faucet and in a third position of said valve said source conduit means is connected to said - faucet, -and an - override switch for said electric motor operable by movement of said valve such that in said first and

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (10)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   the sensing element of the micro-switch 78 turns the latter on, which permits the pump 67 to be energized whenever the tap (discussed in relation to the earlier Figures) is turned on. The micro-switch 78 is turned on only in position number 2, where the flow of water is adapted to pass directly from the tank 66 through the pump 67 to the taps in the trailer or boat. In both of the other conditions, the overriding microswitch 78 is off, whereby the opening of one of the taps or valves discussed in connection with the earlier Figures will not energize pump 67 (since it is not needed in either case).

   In a preferred embodiment of this invention, the valve 70 will be mounted in close association with the standard connector 73, and the rotary portion of the valve 70 will have an outwardly projecting finger or "mask" portion adapted to be situated in front of the connector 73 whenever the valve is in position number 2, namely the position where water to the taps is coming directly from the tank 66. This will prevent dirt and dust from entering the connector 73 under these circumstances. In the other two positions of the valve 70, of course, a hose from the city water eonnection would be coupled to the connector 21, thus - eliminating any problem of dirt or dust contamination in this respect.

   Attention is now directed to Figures 8 10, which show schematically a valve construction which may be substituted for the valve 70 in Figure 7. These figures illustrate the operative portions of a valve which includes sliding gate 83 having two apertures 84 and 85 therethrough.

   A line 86 from the pump leads through a check-valve 87 and can pass water directly-through to the line 89 whenever one of the apertures 84 and 85 is in alignment with these two lines. City water comes in through- a line 90 and through a checkvalve - 91 to - be directly connected to the line 89. Both of these are in full communication with a line 93 which goes to the taps in the boat or trailer A further line 95 is in- con'plete communication with the tap, the city water and the line 89, and leads up against the gate 83 so as-to be blocked thereby in certain of its positions. On the other side of the gate 83, the line 95 communicates through to a line 97 which passes to the filling opening of the tank.

   In the particular position shown in Figure 8, the -opening 84 is interposed in alignment between the lines 86 and 89, such that water can be pumped directly from the tank to the taps. The water- cannot get out into the city water system due 'to the checkvalve' gl, and cannot recirculate back'to the tank fill due to the fact that there is no aperture allowing communication - between the lines 95 and 97. Thus Figure 8 represents the mode in which water from the tank can be pumped to the taps. This corres- ponds to the position number 2 in Figure 7, in which the microswitch 78 is "on" and allows energization of the pump 67.

   In Figure 9 the gate 83 is in an intermediate position, in which neither of the openings 84 and 85 is interposed in any of the lines. Thus, water cannot be pumped from the tank along line 86, and water cannot be recirculated to fill the tank along line 97. However water from the city water system can pass through the check-valve 91 and along line 93 to the taps. Figure 9 corresponds to position 3 in Figure 7, in which the microswitch 78 is "off", preventing operation of the pump 67.

   Figure 10 shows a condition in which the two apertures 84 and 85 are interposed against the lines 97 and 86, respectively. In this mode, water from the city water system under pressure can pass through the checkvalve 91 and along the filling line 97 to fill the tank. Water from the city water system could not pass along the line 86 due to the presence of the check-valve 87. At the same time in Figure 10, water from the city water system could pass out along line 93 to the taps, if these should be turned on.

   Figure 10 corresponds to some extent to position 1 in Figure 7, and certainly in this mode the microswitch 78 would be turned "off", so that the accidental opening of one of the taps during the filling operation -would not call upon the pump 67 to pump against a closed gate.

   Reference should be made to co-pending Patent application No. 41082/75 (Serial No. 1559817) from which the present application is divided and to co-pending Patent application No. 28575/78 (Serial No.

   1559818) which is also divided from application No. 41082/75. Both these applica-- tions include claims to features of the apparatus described herein; WHAT WE- CLAIM IS:- 1. A liquid supply - apparatus including a pump for pumping liquid from a liquid reservoir to a faucet, an electric motor operatively connected to said pump, conduit means for connection of the apparatus to a source of liquid under pressure, a valve having at least three outlets and con-nected (a) to said source conduit means, (b) to said faucet and (c) to said reservoir; such that in a-first position of said valve said source conduit means is connected to the reservoir, in a second position of said valve said reservoir is connected to said faucet and in a third position of said valve said source conduit means is connected to said - faucet, -and an - override switch for said electric motor operable by movement of said valve such that in said first and

   third positions said override switch is operative to de-energise said pump motor and in said second position said override switch permits said pump motor to be energised.
2. 2. Apparatus as claimed in claim 1 wherein said source conduit means terminates adjacent said valve and the valve includes a masking portion movable therewith and adapted when the valve is in said second position to cover the termination of said conduit means for preventing ingress of dirt, grease and other contaminants.
3. 3. Apparatus as claimed in claim 1 or 2 wherein said valve includes a rotatable cam for operating said override switch.
4. 4. Apparatus as claimed in any preceding claim wherein said valve includes a rotatable valve member.
5. 5. Apparatus as claimed in claim 4 wherein said valve has a fourth connection through a shut-off valve along a filling line to said reservoir to fill the same, and in which a line interconnecting the reservoir the pump and said faucet resists liquid movement in the reverse direction from the pump to the reservoir when the pump is shut off.
6. 6. Apparatus as claimed in any of claims 1 to 3 wherein said valve includes as a valve member a sliding gate having two apertures therein.
7. 7. Apparatus as claimed in claim 6 wherein said source conduit means includes a one-way check valve, said pump is connected to said three-way valve by way of a one-way check valve, and said three-way valve is connected to said reservoir by a filling line.
8. 8. Apparatus as claimed in any preceding claim wherein said faucet is arranged to control switch means for energising said pump motor such that when said faucet is closed, said pump motor is de-energised and when the faucet is opened said pump motor is energised.
9. 9. Apparatus as claimed in claim 8 wherein said faucet includes a rotatable shaft for moving a valve member within a fluid passageway, and when said shaft is moved a small amount from said closed faucet position, said switch means is operative to energise the pump motor, either before or after the fluid passageway is partly opened.
10. 10. A liquid supply apparatus as claimed in claim 1 and substantially as described with reference to Figures 7 to 10 of the accompanying drawing.