GB2324594A

GB2324594A - Immersion heater mounting

Info

Publication number: GB2324594A
Application number: GB9808531A
Authority: GB
Inventors: Rainer Sickmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-04-23
Filing date: 1998-04-23
Publication date: 1998-10-28
Also published as: GB9808531D0

Abstract

An assembly for fitting an immersion heater to a hot water cylinder 16, the immersion heater including a heating element 13 and a water circulator device 14. The water circulator device 14 comprises a circulator casing which fits over the heating element, and an upstand pipe 17 which directs heated water to the top of the hot water cylinder. The assembly includes apparatus which enables the rotational orientation of the water circulator device to be adjusted to a predetermined orientation and apparatus for fixedly securing the water circulator device. The upstanding pipe 17 may be secured to the circulator casing 14 such that at least a portion of the upstanding pipe 17 lies within the circulator casing 14 (see Figure 3A, not shown).

Description

Immersion Heater Assembly This invention relates to an assembly for fitting an immersion heater to a hot water cylinder.

Electric immersion heaters such as those used in domestic hot water cylinders may be provided with a circulator device which provides an efficient and economical method of heating water in a hot water cylinder. The circulator device consists of a circulator casing which typically fits over the heating elements of an immersion heater. The circulator device also incorporates an upstand pipe which extends from one end of the circulator casing to the top of the inside of the hot water cylinder. In this way, hot water is provided at the top of the cylinder at the point where it is drawn from the tank. Such a circulator requires an immersion heater in which the position of the heating plate of the immersion heater with respect to the wall of the hot water cylinder can be placed in such a way as to ensure that the upstand pipe be located vertically. This is accomplished utilising a shaped flange, typically oval in shape, which ensures correct positioning of the element and therefore of the circulator casing and the upstand pipe.

Alternative immersion heaters incorporate a round threaded neck, where the immersion heater is attached to the hot water cylinder via the screw threads on the neck of the immersion heater, typically by means of a circular threaded joint on the hot water cylinder itself. These immersion heaters are now commonplace, however they do not enable a circulator device to be utilised. This is due to the circular screw threaded joint which is provided between the immersion heater and the hot water cylinder which does not enable the immersion heater to be precisely rotationally oriented.

These immersion heaters are not as efficient or as economical as the immersion heaters which incorporate a circulator device.

Accordingly, it is an object of the present invention to provide a heater end assembly enabling the use of a circulator device in conjunction with screw threaded joint immersion heaters.

According to a first aspect, the present invention provides an assembly for mounting an immersion heater in a wall of a hot water cylinder, said immersion heater being of the type comprising a heating element enclosed within a circulator casing such that, in use, said circulator casing having a longitudinal axis which extends into the interior of the hot water cylinder from said wall and is oriented about said longitudinal axis in a predetermined manner with respect to the cylinder, the assembly comprising means whereby said circulator casing may be located in or adjacent to an aperture formed in said wall of said hot water cylinder and rotated about said longitudinal axis prior to being secured relative to said wall in said predetermined orientation.

The assembly may include an annular flange member to which an end of said circulator casing is connected, in use, said annular flange member being adapted to be seated against a first annular shoulder surrounding said aperture formed in said wall of the hot water cylinder, and may further include locking means whereby said flange member may be rotated relative to said first annular shoulder prior to being secured thereto in said predetermined orientation.

The assembly may further include a generally tubular adaptor ring having a first end and a second end, said first end having a first externally threaded portion adapted to be inserted into said aperture from the exterior thereof and to threadably engage an internally threaded bushing located in said aperture, wherein said first annular shoulder is provided by said second end of said adaptor ring, and the assembly may further include a locking member whereby said annular flange member may be clamped against said second end of said adaptor ring.

The annular flange member may comprise a peripheral part of a baseplate member to which said circulator casing is adapted to be secured, in use.

Said second end of said adaptor ring may include a second externally threaded portion and said locking member may include a second internally threaded portion adapted to engage said second externally threaded portion and a second annular shoulder adapted to clamp said flange member against said first annular shoulder when said second internally and externally threaded portions are engaged and tightened.

The adaptor ring may further include an external annular flange having a first side which seats against said bushing located in said aperture and a second side against which said locking ring seats when engaged with said adaptor ring.

The assembly may further include a first annular fluid seal which surrounds said first externally threaded portion of said adaptor ring and which is interposed, in use, between said first side of said external annular flange of said adaptor ring and said bushing located in said aperture.

The assembly may further include a second annular fluid seal interposed between said annular flange member and said first annular shoulder.

The annular shoulder may be formed in the interior of a bushing located in said aperture.

Said annular flange member may be formed integrally with said circulator casing.

Said bushing may include a first internally threaded portion adjacent said first annular shoulder on the exterior side thereof, and the assembly may further include an externally threaded locking ring adapted to threadably engage said first internally threaded portion of said bushing.

Said bushing may include a second internally threaded portion adjacent said first internally threaded portion on the exterior side thereof, and said second internally threaded portion may be adapted to be threadably engaged, in use, by an externally threaded mounting collar of an immersion heater element device,such that the immersion heater element extends through said bushing into the interior of the circulator casing.

According to a second aspect, the present invention provides a water heater comprising a hot water cylinder and an immersion heater having a circulator casing, wherein said circulator casing is secured to said cylinder by means of a mounting assembly as defined above.

According to a third aspect, the present invention provides circulator apparatus for an electric immersion heater including a circulator casing and an upstand pipe which is secured to the circulator casing, characterised in that the upstand pipe is secured to the circulator casing via an access port in the circulator casing such that at least a portion of the upstand pipe lies within the circulator casing.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings of which: Fig. 1A is an exploded cross-sectional side view of one embodiment of the invention; Fig. 1B is an end view of a baseplate member forming part of the assembly of Fig. lA; Fig. 1C is an end view of a locking ring of Fig.

lA; Fig. 2 shows the assembly of Fig. 1 in use; Fig. 3A is a cross-sectional side view of an alternative embodiment; and Fig. 3B is an end view of a locking ring of Fig.

3A.

Referring to Fig. 1 and Fig. 2, a wall 1 of a hot water cylinder 16 is shown having a bush assembly 2 mounted within a hole 3 in the wall 1 of the hot water cylinder 16. An adaptor ring 4 is joined to the bush assembly 2 via screw threads 5 in a leading edge of the adaptor ring 4 and screw threads 6 in the bush assembly 2. A fluid seal 7 is provided between the adaptor ring 4 and the bush assembly 2. In this way, a sealed junction is provided between the adaptor ring 4 and the bush assembly 2 when the adaptor ring 4 is joined to the bush assembly 2.

Subsequently, a baseplate member 8 is located within the trailing edge of the adaptor ring 4. A peripheral part of the baseplate member 8 forms an annular flange member. The baseplate member 8 has two holes 39 therethrough for the location of a heating element 13 which is attached to the baseplate member 8 via the two holes 39. These holes 39 enable the rotational position of the baseplate member 8 with respect to the bush assembly 2 to be verified. A third hole (not shown) may be provided on the baseplate member 8 for the location of a thermostat tube and thermostat (not shown). A locking member in the form of a locking ring 9 is provided for fixedly retaining the annular flange member portion of the baseplate member 8 to retain the baseplate member 8 in its rotationally oriented position. The locking ring 9 is provided with screw threads 10 on its inside face such that the locking ring 9 may be joined to the adaptor ring 4 via the screw threads 11 on the outside face of the trailing edge of adaptor ring 4. A further fluid seal 12 may be provided between the baseplate member 8 and the adaptor ring 4 to provide a sealed junction between the hot water cylinder 16 and the immersion heater assembly.

The seal 12 is of a suitable known material.

The baseplate member 8 and associated heating element 13 is adapted to co-operate with a water circulator device which includes a circulator casing 14 . The circulator casing 14 may be attached to the baseplate member 8 such that when the rotational position of the baseplate member 8 with respect to the bush assembly 2 in the wall 1 of the hot water cylinder 16 is adjusted, the corresponding rotational position of the circulator casing 14 with respect to the bush assembly 2 is also adjusted.

In this way, the circulator casing 14 may be oriented such that an upstand pipe 17 fixed to the circulator casing 14 stands substantially vertically within the hot water cylinder 16. Thus when water in the hot water cylinder 16 is heated at the element 13 within the circulator casing 14, the water passes through the circulator casing 14, being drawn in through the access port 15, and rises through the upstand pipe 17. The upstand pipe 17 is connected to the circulator casing 14 via a short inter-connection tube 18, and this enables hot water to be delivered to the top of the hot-water cylinder 16. Thus hot water is provided at the top of the hot water cylinder 16 close to the drawoff pipe 19, which is used to draw hot water out of the hot water cylinder 16.

The problem encountered with modern immersion heaters whereby water circulator devices (such as that shown in Fig 2) cannot be utilised, because the circulator casing and associated upstand pipe cannot be correctly oriented, is overcome by the ability of the baseplate member 8 and the circulator casing 14 to be rotationally oriented. This enables the upstand pipe 17 to be located substantially vertically within the hot water cylinder 16.

An alternative embodiment of the invention is shown at Fig. 3. In this embodiment, the circulator casing 20 is shown having an annular flange member 21. The annular flange member 21 of the circulator casing 20 is located between a shoulder 22 of the bush assembly 23 in the wall 1 of the hot water cylinder 16 (shown in Fig. 2) and a locking ring 24. The locking ring 24 is provided with screw threads around its circumference which co-operate with screw threads around the inner circumference of the bush assembly 23 in the wall 1 of the hot water cylinder 16. The screw threads are indicated at 25. The locking ring 24 is also provided with holes 35 therethrough for the location of a fixing tool (not shown) by which means the locking ring 24 may be secured.

In this way, the circulator casing 20 may be precisely rotationally oriented within the hot water cylinder 16 such that the upstand pipe 26 may be located substantially vertically, the circulator casing 20 being secured in the desired position utilising the locking ring 24.

Subsequently, an immersion heater generally shown at 27 (which may be an immersion heater of a known type), having heating elements 28 is located through the bush assembly 23 in the wall 1 of the hot water cylinder 16, such that the heating elements 28 lie within the circulator casing 20 in the hot water cylinder 16. A fluid seal 29 of a suitable known material is provided between the immersion heater 27 and the bush assembly 23. The immersion heater 27 may also incorporate a thermostat tube and thermostat (not shown). The fluid seal 29 has an inside diameter greater than the outside diameter of a protruding portion 30 of the immersion heater 27 such that the fluid seal 29 fits over the portion 30. The portion 30 is of outside diameter less than the inside diameter of the bush assembly 23 and has screw threads around its outer circumference which co-operate with screw threads around the inner circumference of the bush assembly 23. The screw threads are generally shown at 31. Thus the immersion heater 27 may be fixedly secured within the bush assembly 23 in the wall 1 of the hot water cylinder 16, thereby providing a sealed junction between the hot water cylinder 16 and the immersion heater assembly.

Water enters the circulator casing 20 via an access port 32 where it is heated at the heating elements 28.

It will be appreciated that the circulator device of the Fig 3 embodiment may be of the type shown in the embodiment of Fig 1. In the Fig 3 embodiment, a circulator device is shown wherein the water heated by the heating elements 28 passes by convection into the upstand pipe 26 and to the top of the hot water cylinder 16, via a port 33 in the wall of the upstand pipe 26. The upstand pipe 26 is located in the circulator casing 20 via an access port 34. The upstand pipe 26 and the end wall 36 of the circulator casing 20 are provided with a passage 37 therethrough for the location of a retaining screw 38 which enables the upstand pipe 26 to be secured within the circulator casing 20.

The embodiment of Fig 3 provides an alternative arrangement for overcoming the problem encountered with modern immersion heaters, since the circulator casing 20 may be rotationally oriented and secured prior to locating the immersion heater 27. This enables the upstand pipe 26 to be located substantially vertically within the hot water cylinder 16. The rotational orientation of the immersion heater 27 is not important in the embodiment of Fig 3 as the circulator casing 20 may be rotationally oriented independently of the immersion heater 27 and the heating elements 28.

An immersion heater utilising circulator apparatus provides a faster, more efficient method of heating water than those where circulator apparatus cannot be utilised.

Modifications and improvements may be made to the foregoing within the scope of the invention.

Claims

1. An assembly for mounting an immersion heater in a wall of a hot water cylinder, said immersion heater being of the type comprising a heating element enclosed within a circulator casing such that, in use, said circulator casing having a longitudinal axis which extends into the interior of the hot water cylinder from said wall and is oriented about said longitudinal axis in a predetermined manner with respect to the cylinder, the assembly comprising means whereby said circulator casing may be located in or adjacent to an aperture formed in said wall of said hot water cylinder and rotated about said longitudinal axis prior to being secured relative to said wall in said predetermined orientation.

2. An assembly as claimed in Claim 1, including an annular flange member to which an end of said circulator casing is connected, in use, said annular flange member being adapted to be seated against a first annular shoulder surrounding said aperture formed in said wall of the hot water cylinder, and further including locking means whereby said flange member may be rotated relative to said first annular shoulder prior to being secured thereto in said predetermined orientation.

3. An assembly as claimed in Claim 2, further including a generally tubular adaptor ring having a first end and a second end, said first end having a first externally threaded portion adapted to be inserted into said aperture from the exterior thereof and to threadably engage an internally threaded bushing located in said aperture, wherein said first annular shoulder is provided by said second end of said adaptor ring, the assembly further including a locking member whereby said annular flange member may be clamped against said second end of said adaptor ring.

4. An assembly as claimed in Claim 3, wherein said annular flange member comprises a peripheral part of a baseplate member to which said circulator casing is adapted to be secured, in use.

5. An assembly as claimed in Claim 3 or Claim 4, wherein said second end of said adaptor ring includes a second externally threaded portion and said locking member includes a second internally threaded portion adapted to engage said second externally threaded portion and a second annular shoulder adapted to clamp said flange member against said first annular shoulder when said second internally and externally threaded portions are engaged and tightened.

6. An assembly as claimed in Claim 5, wherein said adaptor ring further includes an external annular flange having a first side which seats against said bushing located in said aperture and a second side against which said locking ring seats when engaged with said adaptor ring.

7. An assembly as claimed in Claim 6, further including a first annular fluid seal which surrounds said first externally threaded portion of said adaptor ring and which is interposed, in use, between said first side of said external annular flange of said adaptor ring and said bushing located in said aperture.

8. An assembly as claimed in any one of Claims 2 to 7, further including a second annular fluid seal interposed between said annular flange member and said first annular shoulder.

9. An assembly as claimed in Claim 2, wherein said first annular shoulder is formed in the interior of a bushing located in said aperture.

10. An assembly as claimed in Claim 9, wherein said annular flange member is formed integrally with said circulator casing.

11. An assembly as claimed in Claim 9 or Claim 10, wherein said bushing includes a first internally threaded portion adjacent said first annular shoulder on the exterior side thereof, the assembly further including an externally threaded locking ring adapted to threadably engage said first internally threaded portion of said bushing.

12. An assembly as claimed in Claim 11, wherein said bushing includes a second internally threaded portion adjacent said first internally threaded portion on the exterior side thereof, said second internally threaded portion being adapted to be threadably engaged, in use, by an externally threaded mounting collar of an immersion heater element device,such that the immersion heater element extends through said bushing into the interior of the circulator casing.

13. A water heater comprising a hot water cylinder and an immersion heater having a circulator casing, wherein said circulator casing is secured to said cylinder by means of a mounting assembly as claimed in any one of Claims 1 to 12.

14. Circulator apparatus for an electric immersion heater including a circulator casing and an upstand pipe which is secured to the circulator casing, characterised in that the upstand pipe is secured to the circulator casing via an access port in the circulator casing such that at least a portion of the upstand pipe lies within the circulator casing.