IE74131B1

IE74131B1 - Improvements in or relating to ablutionary installations

Info

Publication number: IE74131B1
Application number: IE930810A
Authority: IE
Inventors: Stephen Russel Georg Thorndale; Terence Leslie Winnington
Original assignee: Caradon Mira Ltd
Priority date: 1992-10-31
Filing date: 1993-10-26
Publication date: 1997-07-02
Also published as: GB2272023A; GB9222870D0; IE930810A1; GB2272023B

Abstract

A centrifugal pump 8 has parallel inlet and outlet connections 18 and 22 respectively on one side of an impeller 17, and a spiral flow diffuser 19 of increasing cross-section in the direction of flow from the periphery of the impeller 17 to an outlet chamber 21 concentric with the inlet 18. The impeller 17 is mounted on a drive shaft 16 of a motor 9 controlled by a flow responsive switch 24 positioned in the outlet 22.

Description

This invention concerns improvements in or relating to ablutionary installations and in particular, though not exclusively, ablutionary shower installations of the kind in which there is a shower head to which water is supplied by a connection to a source of preconditioned water at a desired or predetermined or selected temperature.

The water source may be a mixing valve connected to the hot and cold supplies or a water heater connected to the cold supply. In many installations, it is necessary to boost the water pressure to obtain a satisfactory spray by pumps fitted in the water circuit.

Centrifugal pumps commonly have an outlet tangential to the purrip motor housing and this can give rise to problems in making the necessary .connections where the available space is limited.

The present invention has been made from a consideration of this problem and has for its object the provision of a centrifugal pump which can be fitted in a simple manner.

Other features, benefits and advantages of the invention will be understood from the description of the exemplary embodiments herein.

According to a first aspect of the invention there is provided a centrifugal pump comprising a casing having a water inlet and a water outlet parallel to the water inlet, an impeller mounted for rotation in the casing, an insert received in the casing for conducting water from the water inlet to the impeller and for conducting pumped water from the impeller to the water outlet, a pumping chamber bounded by an outer wall of the insert peripherally of the impeller, and a flow diffuser provided by a spiral duct in the outer wall of the insert arranged to receive pumped water from the pumping chamber and to conduct the pumped water to the water outlet with the spiral duct being of increasing cross-section in the direction of water flow.

The spiral duct diffuses the pumped water so that the velocity energy in the pumped water leaving the impeller is changed in part into pressure energy reducing the water velocity and enables the water outlet to be arranged parallel to the water inlet. In this way, the water connections to the pump are simplified for fitment of the pump, especially where the available space is limited. -2741 31 Advantageously, the water inlet and water outlet are provided on the same side of the impeller. As a result, the pump is compact with only limited access required for making the water connections.

Preferably, the water outlet is in communication with an outlet chamber arranged to receive pumped water from the spiral duct.

Advantageously, the outlet chamber is concentric with the water inlet. By such arrangement, the water outlet can be provided at any desired location with respect to the water inlet.

Preferably, the pump is controlled by switch means responsive to water flow so that the pump operates only when there is sufficient water flow.

Advantageously, the switch means is located at the water outlet and is magnetically actuated by displacement of a piston between first and second positions in response to water flow to control operation of the pump.

Preferably, the piston is resiliently biased to the first position in which the pump is switched off, and is movable in response to water flow against the biasing to the second position for switching the pump on.

By such resilient biasing, the piston is automatically returned to the first position to switch the pump off when there is insufficient water flow. Furthermore, the pump can be installed with the water outlet directed downwards without affecting operation of the switch means.

Advantageously, the piston is a close fit in the outlet in the first position and a clearance fit in the outlet in the second position with respective guide vanes at each end for locating and aligning the piston in the outlet.

Preferably, the pump is driven by an electric motor controlled by the switch means in response to water flow. In a preferred arrangement, the impeller is mounted on a shaft rotatable by the motor with the motor positioned on the side of the impeller remote from the water inlet and water outlet.

According to a second aspect of the invention there is provided a pump unit for an ablutionary shower installation comprising the pump according to the first aspect of the invention housed in a mounting box providing an enclosure for the pump.

Preferably, the pump is mounted on a back wall of the box and a front cover of the box is removable for access to the pump. -3Advantageously, the mounting box has a slide rail provided with an adjustable support bracket for a spray head.

Preferably, the slide rail is provided with an apertured ring member for passage of a flexible pipe connecting the water outlet to the spray head.

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings wherein:FIGURE 1 is a perspective view of an ablutionary shower installation embodying the invention; FIGURE 2 is a side view of the booster pump unit shown in Figure 1; FIGURE 3 is a front view of the booster pump unit shown in Figure 2 with the cover removed; . FIGURE 4 is a front view similar to Figure 3 with the pump shown in section; FIGURE 5 is a front view similar to Figure 4 with the pump shown in part section; and FIGURES 6a.b.c are cross-sections through the flow switch showing different stages of operation.

The ablutionary shower installation shown in the accompanying drawings comprises a booster pump unit 1 connected by respective flexible pipes 2 and 3 to a source of preconditioned water (not shown) and a shower spray head 4.

The source of preconditioned water may be a mixing valve for hot and cold water to provide water having a temperature selected by the user, and the booster pump unit 1 is operable to increase the pressure of the preconditioned water supplied to the spray head 4.

The spray head 4 comprises a handset carried by an adjustable support bracket 5 mounted on a slide rail 6 of the booster pump unit 1.

The support bracket 5 can be slid up and down the rail 6 and clamped at any adjusted position to vary the vertical height of the spray head 4 above the base of the installation, for example a shower tray or bath.

The support bracket 5 is also adjustable to vary the attitude of the spray head 4 in any adjusted position.

The spray head 4 is detachable from the support bracket 5 and is prevented from positioning below the spillover level of the base of the installation by passing the flexible pipe 3 through a retainer ring 7 mounted at the lower end of the slide rail 6. -4The booster pump unit 1 comprises a centrifugal pump 8 and a motor 9 supported on the back wall 10 of a rectangular mounting box 11 provided with through holes for screws 12 to fix the mounting box 11 to a wall structure.

The slide rail 6 extends vertically upwards from the mounting box 11 and is secured at the lower end by the upper fixing screw 12. The upper end of the rail 6 is secured by a mounting bracket 13 fixed to the wall structure by screws (not shown).

The mounting box 11 is closed by a mating rectangular cover 14 to form an enclosure 15 for the pump 8 and motor 9. The cover 14 is releasably secured to the mounting box 11 for installation and maintenance .of the booster pump unit 1.

The motor 9 is mounted above the pump 8 and has a drive shaft 16 on which an impeller 17 of the pump 8 is mounted.

The pump 8 has a casing 8a in which the impeller 17 is received. The casing 8a has a water inlet 18 and a water outlet 22 at the lower end on the side of the impeller 17 remote from the motor 9.

The water outlet 22 extends parallel to the water inlet 18 and is connected to the spray head 4 by the pipe 3. The water inlet 18 is coaxial with the drive shaft 16 and is connected to the source of preconditioned water by the pipe 2.

An insert 33 is located in the casing 8a and is arranged to conduct water from the inlet 18 to the impeller 17 and from the impeller 17 to an outlet chamber 21 in communication with the outlet 22. The outlet chamber 21 is concentric with the inlet 18.

A pumping chamber 34 is bounded peripherally of the impeller 17 by an outer wall 33a of the insert 33 and communicates with a flow diffuser 19 provided by a spiral duct 20 in the outer wall 33a of the insert 33.

The duct 20 is bounded peripherally of the insert 33 by the casing 8a and is of progressively increasing cross-section in the direction of water flow from the pumping chamber 34 to the outlet chamber 21 so as to diffuse the pumped water.

The motor 9 is connected to a power source (not shown) such as the mains electricity supply via a switch relay 23 controlled by switch means 24 responsive to water flow at the outlet 22. -5The switch means 24 comprises a reed switch 25 that is actuated by a magnet 26 carried by a piston 27 mounted in the outlet 22.

The piston 27 is a close fit in a first bore portion 28 of the outlet 22 and a clearance fit in a second bore portion 29 of the outlet 22.

The piston 27 has guide vanes 30 at one end sized to fit the first bore portion 28 and guide vanes 31 at the other end sized to fit the second bore portion 29.

The reed switch 25 is positioned externally of the second bore portion 29 and the piston 27 is axially biased by a spring 32 to the position shown in Figure 6a in which it is received in and substantially blocks the first bore portion 28 when there is no water flow.

In this position, the reed switch 25 is open and the relay 23 is switched to interrupt the power supply to the motor 9 so that the pump 8 does not operate.

The piston 27 is displaced against the spring bias as water flow occurs and, as it reaches the intermediate position shown in Figure 6b, the reed switch 25 is closed by the magnet 26 and the relay 23 is switched to connect the power supply to the motor 9 thereby bringing the pump 8 into operation to boost the water pressure.

As the water pressure increases, the piston 27 is moved to the position shown in Figure 6c in which it no longer blocks the first bore portion 28 allowing water to flow around the outside of the piston 27 through the outlet 22 to the spray head 4.

On cessation of the water flow, the piston 27 is automatically returned to the position shown in Figure 6a by the spring 32. As a result, the reed switch 25 is opened and the relay 23 is switched to interrupt the power supply to the motor 9 so that the pump 8 stops.

As will be understood, the parallel arrangement of the water Inlet 18 and water outlet 22 on the same side of the impeller 17 is compact and simplifies connection to the water source and spray head 4.

The water source may be a mixing valve as described or an instantaneous water heater or any other suitable controllable water supply. Preferably, the water source is adapted to maintain the selected water temperature substantially constant, for example a thermostatically controlled mixing valve. -6The spray head may be adjustable to vary the spray type and/or pattern and may be incorporated in a handset as shown or wall mounted.

It will be understood that the invented centrifugal pump has general application and use where it is desired to boost water pressure for any reason and is not limited to the shower booster pump unit above-described. Such applications and uses will be apparent to those skilled in the art and are deemed to be within the scope of the invention.

It will also be appreciated that the invented centrifugal pump abovedescribed may be modified without departing from the concept of parallel inlet and outlet with spiral diffuser. For example, the flow switch may be of any suitable type and may be arranged to sense water flow at the inlet. For .some applications, the flow switch may be replaced by a manually operable switch to activate the pump motor. Other variations and modifications will be apparent to those familiar with the diverse applications and uses of centrifugal pumps and are deemed to be within the scope of this invention.

Claims

1. A centrifugal pump comprising a casing having a water inlet and a water outlet parallel to the water inlet, an impeller mounted for rotation in the casing, an insert received in the casing for conducting water from the water inlet to the impeller and for conducting pumped water from the impeller to the water outlet, a pumping chamber bounded by an outer wall of the insert peripherally of the impeller, and a flow diffuser provided by a spiral duct in the outer wall of the insert arranged to receive pumped water from the pumping chamber and to conduct the pumped water to the water outlet with the spiral duct being of increasing cross-section in the direction of water flow. .

2. A centrifugal pump according to Claim 1 wherein the water inlet and water outlet are provided on the same side of the impeller.

3. A centrifugal pump according to Claim 1 or Claim 2 wherein the water outlet is in communication with an outlet chamber arranged to receive pumped water from the spiral duct.

4. A centrifugal pump according to Claim 3 wherein the outlet chamber is concentric with the water inlet.

5. A centrifugal pump according to any one of the preceding Claims wherein the pump is controlled by switch means responsive to water flow.

6. A centrifugal pump according to Claim 5 wherein the switch means is located at the water outlet and is magnetically actuated by displacement of a piston between first and second positions in response to water flow to control operation of the pump.

7. A centrifugal pump according to Claim 6 wherein the piston is resiliently biased to the first position in which the pump is switched off, and is movable in response to water flow against the biasing to the second position for switching the pump on.

8. A centrifugal pump according to Claim 6 or Claim 7 wherein the piston is a close fit in the outlet in the first position and a clearance fit in the outlet in the second position with respective guide vanes at each end for locating and aligning the piston in the outlet.

9. A centrifugal pump according to any one of Claims 5 to 8 wherein the switch means controls a motor for the pump in response to water flow.

10. A centrifugal pump according to Claim 9 wherein the impeller is mounted on a rotatable drive shaft of the motor. -811. A centrifugal pump according to Claim 9 or Claim 10 wherein the motor and water inlet are arranged on opposite sides of the impeller.

11. 12. A centrifugal pump according to any one of the preceding Claims substantially as hereinbefore described with reference to the accompanying 5 drawings.

12. 13. A pump unit comprising the centrifugal pump according to any one of the preceding Claims housed in a mounting box providing an enclosure for the pump.

13. 14. A pump unit according to Claim 13 wherein the pump is mounted on a 10 back wall of the box and a front cover of the box is removable for access to the pump.

14. 15. A pump unit according to Claim 13 or Claim 14 wherein the mounting box has a slide rail provided with an adjustable support bracket for a spray head. 15

15. 16. A pump unit according to Claim 15 wherein the slide rail is provided with an apertured ring member for passage of a flexible pipe connecting the water outlet to the spray head.

16. 17. A pump unit according to any one of Claims 13 to 16 wherein the water inlet is connected to a mixer valve for hot and cold water.

17. 20

18. An ablutionary shower installation incorporating the pump unit according to any one of Claims 13 to 17.