IES58221B2

IES58221B2 - Electrical convector heater

Info

Publication number: IES58221B2
Authority: IE
Inventors: Ronald Michael Warren
Original assignee: Bitech Eng
Priority date: 1991-11-19
Filing date: 1992-11-03
Publication date: 1993-08-11
Also published as: ES1022967U; GB2261723B; FR2683895B3; IES922787A2; GB9124662D0; ES1022967Y; FR2683895A3; DE9214962U1; BE1006459A6; AU634701B3; GB2261723A

Abstract

An electrical convector heater comprising a casing (1) adapted to receive a heating element (15) supported by a side portion (6) when fitted to the body portion (1). Perforate closure members (3, 19) act as an air outlet and air inlet for the air convector chamber within body portion (1). The body portion (1) is selected from a range having different lengths for accommodating suitably dimensioned heating elements (15), 50 that similar side portions (6) can be fitted to body portions (1) of different lengths to vary the side or rating of the convector heater. The controls are all mounted in the side portion (6).

Description

ELECTRICAL· CONVECTOR HEATER This invention relates to an electrical convector heater.

Various designs of electrical convector heaters have evolved with the passage of time but these designs generally include a casing in which one or more electrical heating elements are mounted together with the necessary electrical components for making electrical connections with, for supporting and for controlling the elements. The casing has an air inlet and outlet and may further include an electrical fan to increase the throughput of air, i.e. to provide forced convection, instead of natural convection.

It is a time-consuming operation to assembly the various parts of conventional convector heaters and variations in design, e.g. either to change the appearance, or the nominal rating, or both, usually involves re-tooling and changes in the assembly procedure.

The present invention seeks to facilitate the manufacture and assembly of an electrical convector heater, especially to reduce assembly time where the size and/or design of the heater needs to be changed to suit customer requirements.

EP-A-0 237 428 discloses an electrical convector heater having a thermostat assembly comprising a housing through which pass end portions of a heating element. The housing contains electrical components for connecting and controlling an external supply of electricity to the heating element. The thermostat housing is contained by a body portion, i.e. within a convection chamber in the body portion. No specific means are described for supporting the heating element in the body portion of the convector heater but it is clear that (from a safety point of view) the heating element is not mounted on the thermostat housing. This reference does not address the problem solved by the present invention.

In accordance with the invention, an electrical convector heater comprises a body portion in which is received at least one heating element, the body portion defining a convection chamber for air which is heated by v said element, said chamber having an air inlet and an air outlet; a perforate closure member fitted to the air outlet; and a side portion through which pass end portions of said element and which contains electrical components for connecting and for controlling an external supply of electricity to said element, characterised in that said body portion and said heating^ element are each selected from respective ranges of body portions and heating elements having different lengths, whereby the convector heater has a required size or rating, said element is mounted on the side portion, and said side portion is fitted to one side of the body portion on the exterior of the convector chamber.

As the heating element is mounted on the side portion and the side portion is fitted to one side of the body portion on the exterior of the convection chamber, and as the side portion contains all of the electrical components, the side portion can be commonly fitted to body portions having different lengths. Heating elements of different lengths can also be easily mounted on the side portion to suit the length of the body portion. The body portion need be only of simple construction (e.g. a pressed steel casing), so that a range of body portions, having different lengths, can easily be manufactured. Hence, a subassembly of the side portion and appropriate dimensioned heating element can be easily fitted to a body portion of a required length so as to provide convector heaters of different sizes, ratings or designs to suit varying customer requirements.

Preferably, the electrical heating element (or elements) is of a type where the electrical connections are made at one end only. These connections and the main means for mounting the element are all suitably provided in the side portion. The main element mounting means is preferably an integral bracket on the side portion. When initially mounted in this way the element extends, in cantilever fashion, from the side portion into the interior of the body portion. However, the remote end of the heating element may be supported by a mounting or bracket on a perforate closure member fitted to the convection air inlet.

According to one embodiment of the invention, an electrical fan is also mounted in the side portion and the side portion includes an outlet for air heated by the element and expelled by the fan.

The invention enables the body portion to be made as a pressed-metal casing, whereby its shape and design can be readily varied (as long as it fits the side portion). The casing may be left open at its lower end but (optionally) a perforate member is fitted thereto in the convection air inlet. A perforate closure member is normally fitted to the convection air outlet. The side portion is preferably a plastics injection moulding in which the above-mentioned main element mounting or bracket is integrally formed. Additional mountings or brackets for the other electrical components may also be integrally formed in the side portion, since this reduces or substantially eliminates the need for separate brackets or mountings. This assists in reducing manufacturing and assembly costs. Where a fan is fitted for forced convection, the side portion may optionally include an integrally moulded part which forms the, or part of the housing or volute chamber for the fan.

This can also reduces manufacturing and assembly costs.

In the preferred embodiment of the invention, the side portion includes an upper closure member on which controls are mounted, this member also preferably being made as an injection moulding. The upper closure member may be integral, or a separate part of the side portion.

The body portion may be provided with means for making a snap fit with the side portion but securing screws, for example, can also be used for safety.

The body portion and the side portion may also be of such a construction that injection moulded feet are snapfitted thereto, the feet being provided to raise the body portion above floor level.

An embodiment of the invention will now be described with reference to the accompanying schematic Drawings in which: Figs 1 and 2 are perspective views of electrical convector heaters in accordance with an embodiment of the invention, Fig. 3 is an exploded view, in perspective and partly cut away showing component parts of the embodiment of the invention, Fig. 4 is a simplified side elevation of a side portion of the heater showing an integral and internal fan moulding, Fig. 5 is a perspective view of an electrical heating element, and Fig. 6 is a perspective view of a bracket for supporting a remote end of the element.

Figs. 1 and 2 each show an electrical convector heater having a body portion 1, which is a sheet metal pressing, joined to a side portion 2, which is of an injection moulded plastics construction. The body portion 1 and side portion each have a generally rectangular cross-section, in a vertical plane. The side portion 2 has a generally Cshaped cross-section in a horizontal plane whereby one end of the body portion 1 is received in the side portion 2.

A perforate closure member or grille 3 extends across the open top of body portion 2 and acts as an outlet for heated air escaping from the heater by natural convection. Another perforate closure member or grille 19 (Fig. 3) is fitted to the open bottom of the body portion 1 so as to act as an inlet for air which is drawn in either natural convection, or by an electrical fan which expels heated air through grille 4 by forced convection. One end of the grille 3 is received in an end closure member 5 and its other end is received in an end closure member 6 in which a thermostatic control knob 7a and switches 8 are mounted.

A timer control knob 7b is mounted on a front face of side portion 2 and it controls a timer (within portion 2) for turing the heater on and off at preselected times. The grille 3, which fits over marginal edges of the body portion and under the end closures 5 and 6 is of pressed metal construction. The end closures are of injection moulded plastics construction. As shown in Fig. 3, end closure member 6 can be integrally formed as part of the side portion 2. Injection moulded plastics feet 9 are a snap fit into the body portion 1 and side portion 2.

The difference between Figs. 1 and 2 is that a forced air outlet 4 is shown in Fig. 1 (which is missing from Fig. 2, since the heater of Fig. 2 operates by natural convection) and that the body portion in the heater of Fig. is longer than that in Fig. 1, so as to receive a longer heating element (not shown), and thereby provide an increased heat output.

Referring to the simplified drawing of Fig. 3, it can be seen that the body portion 1 contains no electrical components and is simply a metal pressing with a cut-outs 10 and 20 in the side panel 11. The body portion 1 defines a convection chamber la having an air inlet lb and an air outlet lc. The panel 11 has inwardly directed edges which are secured together, e.g. by pop rivets or spot welding. The body portion 1 may be left open at the bottom but 5 preferably has fitted thereto a perforate bottom closure member 19 in the convection air inlet lb. Member 19 preferably is provided with a moulded bracket 13 which supports the furthest end 14 of the heating element 15 when the side portion 2 is fitted to the body portion 1. The 10 body portion 1 thereby only receives the heating element 15, which passes through the cut out 10 and is slotted into the bracket 13. Fig. 6 shows an enlarged view of bracket 13 which has a rectangular portion of folded construction to receive end 14 of element 15. It also has legs 13a, 13b 15 with feet for attachment to grille 19.

In Fig. 3, the end closure member 6 is formed as an integral part of side portion 2. Member 5 and grille 3 are similar to those shown in Figs. 1 and 2.

The heating element 15 is mounted, at its other end 16, I - x in brackets 17 which are preferably integral with (but could be secured to) the side portion 2. Thus, in the process of assembly, the heating elements 15 is initially cantilevered 25 from the side portion 2 but its furthest 14 is supported by bracket 13 when the heater is assembled. Fig. 5 is an enlarged view of heating element 15. The element has a double row of hairpin element portions 15a extending from each side, the element portions being supported by an 30 insulating board 15b. Each row of element portions 15a is connected, in series, to respective terminals 15c, 15d and to a common terminal 15e mounted on the board 15b. All electrical connections to element 15 are thus made in side portion 2. The element 15 is selected from a range of 35 elements having different lengths to provide different electrical outputs.

Fig. 4 shows the outside end panel of side portion 2 and indicates (by broken lines) the position of a major part of an integrally mounted fan housing or volute chamber communicating with the grille 4. The integral housing 18 receives an electric motor (not shown) with an impeller (not shown) mounted on its shaft. The fan (when fitted) draws air inwardly from the body portion 1, e.g. through a suitably positioned cut-out 20 in panel 11.

All of the electric components for making connection to and controlling the heating element 15 and the fan 18 (when fitted), including all knobs and switches, are mounted on the side portion 2 and end closure member or portion 6. Hence, the side portion with all of its electrical components can be pre-assembled, together with all cable clamps and terminal blocks etc. before the side portion is fitted to the body portion 1. Preferably, the mountings and brackets (not shown) for these components are integrally formed in the side portion to reduce costs and assembly time.

The body portion 1 is one of a range having different lengths and/or external finishes, the heating element 15 being of an appropriate length to provide the required heat output. Heaters with different ratings and/or external finishes may therefore be quickly assembled to suit customer requirements. If a fan is to be fitted, then the side portion 2 has the integral moulding 18 and outlet grille 4.

To facilitate assembly, the body portion 1 may be provided with spring-loaded tabs (not shown) to engage with corresponding recesses or slots (not shown) in side portion 2, or vice versa.

The feet 9 may be similarly snap-fitted to the base of the body portion 1 at one end and to the base of the side portion 2.

The design and length of the grille 3 can be varied to suit the required dimensions and customer requirements.

Similar switches 8 may be used with different heaters but their external appearance can be varied by using 5 different dollies. The number of switches may be varied (e.g. according to whether a fan is fitted, or not) and the missing switch may be replaced by a blanked-off portion on the moulding. The bank of switches, their associated thermostat knob, and the timer control knob can be located 10 in a recess (22) in the side portion and behind a hinged transparent cover to comply with standards for drip-proof” construction. However, various other arrangements are possible.

Claims

CLAIMS:

1. An electrical convector heater comprising a body portion (1) in which is received at least one heating element (15), the body portion (1) defining a convection chamber (la) for air which is heated by said element (15), said chamber having an air inlet (lb) and an air outlet (lc) ; a perforate closure member (3) fitted to the air outlet (lc); and a side portion (2) through which pass end portions of said element (15) and which contains electrical components for connecting and for controlling an external supply of electricity to said element (15), characterised in that said body portion (1) and said heating element (15) are each selected from respective ranges of body portions and heating elements having different lengths, whereby the convector heater has a required size or rating, said element (15) is mounted on the side portion (2), and said side portion (2) is fitted to one side (11) of the body portion (1) on the exterior of the convector chamber (la).

2. A heater according to Claim 1 wherein the side portion (2) includes an integral means (17) for mounting one end of the heating element (15), said element (15) having electrical connections at one end only.

3. A heater according to any of the preceding Claims wherein an electrical fan is mounted in the side portion and the side portion includes an outlet for air heated by the element and expelled by the fan.

4. A heater according to Claim 3 wherein the body portion (1) is a metal pressing and the side portion (2) is a plastics moulding in which there is provided an integral housing (18) for the fan.

5. A heater according to any of the preceding Claims wherein the body portion (1) and the side portion (2) each have a rectangular section, in a vertical plane, the side portion (2) having a generally C-shaped cross-section in a horizontal plane for receiving one end of the body portion 5 (1) .