GB2217001A

GB2217001A - Mounting cooker hob panels

Info

Publication number: GB2217001A
Application number: GB8803877A
Authority: GB
Inventors: Evor Geoffrey Turner
Original assignee: Electrolux AB
Current assignee: Electrolux AB
Priority date: 1988-02-19
Filing date: 1988-02-19
Publication date: 1989-10-18
Also published as: GB8803877D0

Abstract

A cooker comprises a support chassis 1 and a hob panel 2 attached to and located on the support chassis by resilient engagement via a plurality of brackets 3, 5 disposed between the support chassis and the hob panel. <IMAGE>

Description

A COOKER/HOB ASSEMBLY The present invention relates to cookers of the type comprising a support chassis and a hob panel supported by the support chassis. The invention relates particularly but not exclusively to electric cookers.

Hob panels for cookers are commonly formed from vitreous enameled pressed steel and are attached to the support chassis by means of mild steel brackets. These brackets are generally welded to the hob and are attached to the support chassis with self tapping screws. Electric cooker hobs generally incorporate further steel brackets which are welded to the hob panel and radiant heating elements set into apertures in the hob panel and mechanically fastened to the element brackets with machine screws and nuts. The heating elements are further supported by chrome plated steel spiders typically having three legs which are supported by the perimeter of the hob apertures. Electrical connections and wiring under the hob are protected by conduit assemblies which require further self tapping screws to secure them to the hob panel.

Beside the complexity associated with a large number of welding operations and the use of a large number of self tapping and other screws, difficulties can arise from the use of vitreous enamel coating. For Example, holes pre-pierced in component brackets for fixing screws, typically self tapping screws, are reduced in diameter by the enamel coating which makes the screwing very difficult to achieve. Holes pre-pierced in- component brackets for the fixing of radiant heating elements also have the disadvantage that the vitreous enamel coating acts as an insulator. To overcome this problem, it is necessary to weld monel metal component washers at these positions and to use machine screws and nuts to provide electrical conductivity between the hob panel and radiant heating elements.

Where several welding spots are applied to secure brackets to the hob panel, stresses are sometimes introduced. These stresses can deform the hob and after the hob is vitreous enameled, these stress areas sometimes cause the vitreous enamel to split and to become detached from the hob panel. Even when these problems are avoided, it is difficult to ensure that the brackets are welded in position accurately and specially designed jigs and fixtures (and sometimes special electrode designs) are required to enable access to the welding area.

An object of the present invention is to provide a hob in which welding is eliminated and screw fittings minimised so as to alleviate at least some of the above disadvantages.

Accordingly the invention provides a cooker comprising a support chassis and a hob panel attached to and located on said support chassis by resilient engagement with a plurality of brackets located between said support chassis and hob panel.

Preferably said hob panel has downwardly extending side walls and the inner surfaces of said side walls resiliently engage one or more of said brackets.

Preferably at least one of said brackets engages said hob panel to prevent upward movement thereof.

In a preferred embodiment, the cooker is an electric cooker and at least one heating element is supported in an aperture in hob panel by a spider member having legs which are releasably engaged with the perimeter of the aperture.

This embodiment, at least one heating element is attached to a conduit assembly, said conduit assembly being releasably attached to the underside of said hob panel by cooperating recess and projection configurations formed in the conduit assembly and a downwardly extending wall portion of said hob panel. Such a configuration simplifies the assembly of the cooker.

The invention enables a cooker to be constructed in which only one screw needs to be unscrewed before the entire hob panel assembly can be removed from the support chassis.

Preferred embodiments of the invention are described below by way of example only with reference to figures 1 15 of the accompanying drawings, of which: Figure 1. is a three dimensional exploded view of the main components of a cooker in accordance with the invention; Figure 2. is a three dimensional view, showing a part of the hob panel cutaway to reveal a supporting bracket; Figure 3. is a three dimensional view of a spider used in the cooker of Figure 1; Figure 4. is a representation of the wall portion of a hob panel aperture into which the spider is fitted; Figure 5. is a diametral cross section through one of the hob panel apertures shown in Figure 1; Figure 6. is a cross section through a portion of an aperture side wall showing a locking slot for receiving a leg of the spider shown in Figure 3;; Figure 7. is a similar cross section showing another slot in the side wall of a hob panel aperture; Figure 8. is a cross section showing the attachment of the rear of a conduit assemble shown in Figure 1 to the rear of the support chassis; Figure 9. is a cross section showing the attachment of the front of the hob panel to the front end of a side wall of the support chassis; Figure 10. is a cross section taken on X - X of Figure 12; Figure 11. is a cross section taken on XI - XI of Figure 12; Figure 12. is a plan view of the underside of the hob panel shown in Figure 1; Figure 13. is a similar plan view of an alternative construction, in which the upturned flange shown in Figure 10 does not incorporate a dimple but is profiled to fit the circumference of the hob panel aperture side wall.

Figure 14. shows inside elevation the sequence of operations required to assemble the cooker of Figure 1; Figure 15. shows the corresponding series of operations in plan view.

Figure 1 shows a support chassis (1) on which a hob panel (2) is located by means of two front brackets (5) and two rear brackets (3). The front brackets (5) are screwed onto the support chassis (1) by self tapping screws (6) (only one of which is shown for clarity) and the rear brackets (3) are screwed to the rear wall of the hob panel (2) by self tapping screws (25) (only one of which is shown for clarity). The forks to front bracket (5) and to rear bracket (3) provide a resilient engagement between the hob panel (2) and support chassis (1) as is described in detail below.

A conduit assembly (8) fits beneath the hob panel (2) and conducts electric wiring to four radiant heating elements (7) (only two of which are shown for clarity).

The heating element (7) are secured to the diamond shaped portion (8a) of the conduit assembly by "taptite" screws.

Portion (8a) carries extensions (8b) which engage wall portions (2b) of heating element apertures in the hob plate (2). Conduit assembly (8) includes a tag portion (16) at its rear which is screwed by a self tapping screw (14) to the support chassis (1) at location (15). As will be described in more detail below. The rear portion conduit assembly (8) engages a flange (2a) (Figure 2) extending inwardly from the rear wall of hob plate (2) and thereby prevents the resilient engagement provided by the brackets (3) and (5) from being released. Self tapping screw (14) is the only screw that needs to be undone before the hob plate (2) can be released from support chassis (1).

Each heating element aperture in hob plate (2) is provided with a spider (10) (only two of which are shown for clarity) which supports a respective radiant heating element (7). The spiders (10) engage the wall portions (2b) in a manner described in detail below. The heating element apertures are provided with trim portions (11) (only two of which are shown for clarity) as is conventional. A sleeve (12) is provided for conduit assembly (8) as is conventional.

A splash plate (13) is fitted around and engaged with support brackets (4) which are screwed to the rear of support chassis (1).

Figure 2 shows a portion of hob panel (2) cut away to reveal its engagement with front bracket (5). Bracket (5) is generally of box form and is formed from a generally Tshaped sheet metal stamping, the ends (5a and 5b) of the T-bar being folded inwardly to form parallel side walls and the upright of the T being folded to form a base portion with a downwardly extending portion extending from the base portion (not referenced). The tips (5c and 5d) of ends (5b and 5a) are folded inwardly so as to engage the interior surface of the side wall (2b) of hob panel (2) obliquely. The resilience of the sheet metal brackets (5) ensures that the two brackets (5) press outwardly against the interior of hob panel (2) and prevent it from being displaced sideways.Friction between the edges of tips (5c and 5d) and wall (2b) tend to prevent hob panel (2) from being displaced forwardly or rearwardly. The height of end portions (5a and 5b) of bracket (5) is approximately equal to the height above an inwardly extending flange (2a) to the horizontal portion of hob panel (2) such that engagement between the lower edges of ends (5a and 5b) and flange (2a) prevents the front of hob panel (2) from being lifted off chassis (1).

Rear brackets 3 are of similar configuration to front brackets (5) but face in the opposite directions and are fixed to hob panel (2) rather than support chassis (1) downwardly extending portions (3a) (Figure 1) resiliently engage with the top inner edges of the side walls of chassis (1) to prevent hob panel (2) from being twisted with respect to the support chassis. However, as will be described below the rear of hob panel (2) can be lifted to release the engagement of portions (3a) of brackets (3) with the chassis (1) to enable the hob panel (2) to be removed. Lifting of the rear portion of hob panel (2) is normally prevented by screw (14) which secures conduit assembly (8) to the rear of chassis 1, the conduit assembly (8) itself engaging rear portion of the flange (2a).

Figure 3 shows spider (10). Spider (10) comprises three arms (10a,10b and lOc) which are equiangularly spaced at an Angle of 100 . The free ends of arms (10a,10b and lOc) incorporate stepped portions (one of which is shown at lOd) and these stepped portions engage apertures or slots in hob panel aperture side walls (2b) (Figure 1) as is described below.

Figure 4 shows a side wall (2b) with a looking slot (17) shown and also the locations of (18) prime and (19) prime of two apertures which receive the free ends of the legs of spider (10). The mouth of slot (17) is displaced by an angle from an equiangular spacing as shown.

Accordingly the resilience of the spider arm end slot (17) tends to ensure that the spider arm remains in the locking portion (17a) (Figure 6) of slot (17). As can be seen from Figures 5 and 7, apertures (18) and (19) are rectangular and somewhat greater in height than the stepped portions (lOd) of the spider arms. As can be seen from Figure 5, the heating element (7) is supported on the spider (10).

Figure 8 shows the attachment of conduit assembly (8) to the rear portion of support chassis (1) by screw (14).

Flange (2a) of hob panel (2) extends immediately beneath the rear portion of conduit assembly (8) and thereby prevents the rear of hob panel (2) from being lifted from support chassis (1).

As can be seen from Figure 9, flange (2a) similarly prevents the front of hob panel (2) from being lifted from front bracket (5), which is itself screwed to the side wall of chassis (1) by a screw 6.

Figure 12 shows conduit assembly (8) located on the interior of hob panel (2). The end portion (8a) of conduit assembly (8) is in the form of a parallelogram rather than diamond shaped in Figure 1 but otherwise the arrangement is as in Figure 1. Cover portions (8b) which extend from portion (8a) prime carry dimples (8c) (Figure 10) which engage in apertures located at (2c) (Figures 10 and 12) in the aperture side walls (2b) of the hob panel (2). An alternative embodiment to the dimpled fixing arrangement may be used which incorporates screw fastenings, adhesives or any other suitable method of retention. Covers (8b) protect the terminals of the heating elements (7) (not shown). Similarly, as shown in Figure 11 the rear portion of conduit assembly (8) also carries dimples (8d) which similarly engage in apertures located at (2c).It would be noted that since the heating elements (7) (not shown in Figure 12) are secured to the conduit assembly by "taptite" screws and are supported by the spiders (10) (Figure 1) which are in turn supported and keyed into slot (17) and apertures (18 and 19) (Figures 5 & 6), then the conduit assembly is fully supported. The dimples (8d) serve merely to locate the conduit assembly and hence the heating elements (7).

Figure 13 shows an alternative construction in which the cover portions (8b) prime of conduit assembly (8) have part circular profiles which are complementary to the hob panel aperture to the side walls (2b). However, dimples (8d) maybe provided to located the rear portion of conduit assembly (8) as shown.

Fitting of hob panel (2) to the body of the cooker is illustrated in side elevation in Figures (14a) to (c) and in plan view in Figures (15a) to (c). Referring to Figures 14 and (15a) the hob panel (2) is first positioned above the chassis at an angle as shown and the front portion is lowered onto support bracket (5) as shown by arrow X. The rear portion of the hob panel (2) is raised sufficiently to prevent rear bracket (3) from fouling the support chassis (1) so that the hob panel (2) can be rotated clockwise as shown arrow Y.

When the hob panel (2) is aligned in plan view as shown in Figure (15b) the rear portion thereof is lowered to engage brackets (3) with the interior of the support chassis side walls.

In this position the front bracket (5) capture the hob panel (2) by virtue of the hob panel flange (2a) (Figure 2).

To hold the hob panel (2) to the chassis (1) a single self taping screw (14) (Figure 1) is screwed into downwardly extending portion 16 of conduit assembly (8) to attach it to support chassis (1). The splash plate panel (13) is secured independently to the chassis (1) by using two support brackets (4) as can also be seen from Figure 1. It would be noted that disassembly can be carried out by reversing the above sequence.

Thus a cooker is provided in which only two screws (25 - Figure 1) are required to be inserted into the hob panel (2) and only one screw (14 - Figure 1) is required to be unscrewed to enable the hob panel (2) to be removed.

Furthermore the conduit assembly (8) and heating elements (7) can be rapidly disassembled by unslotting the spiders (10) from the hob panel aperture side walls (2b) thus manufacture and servicing is simplified considerably.

Claims

1. A cooker comprising a support chassis and a hob panel attached to and located on said support chassis by resilient engagement with a plurality of brackets located between said support chassis and hob panel.

2. A cooker as claimed in claims 1 wherein said hob panel has downwardly extending side walls and the inner surfaces of said side walls resiliently engage one or more of said brackets.

3. A cooker as claimed in claim 1 or claim 2 wherein at least one of said brackets engages said hob panel to prevent upward movement thereof.

4. A cooker as claimed in claim 3 as dependent on claim 2 wherein the lower portions of said side walls have an inwardly extending flange whose upper surface engages said at least one bracket.

5. A cooker as claimed in claim 3 or claim 4 wherein at least one other of said brackets normally prevents said hob panel from being rotated in a horizontal plane with respect to said support chassis.

6. A cooker as claimed in claim 5 wherein engagement with said at least one other bracket can be released by tilting said hob panel and engagement with said at least one bracket can subsequently be released by rotating said hob panel, thereby freeing said hob panel from said support chassis.

7. A cooker as claimed in claim 6 wherein disengagement from said at least one other bracket is normally prevented by releasable fixing means.

8. A cooker as claimed in claim 7 wherein said releasable fixing means is provided at one point only on the cooker, and is the only fixing means required to be released before the hob panel can be disengaged from said support chassis.

9. A cooker as claimed in claim 7 or claim 8 wherein said releasable fixing means comprises a conduit which is releasable, engages a side wall of said hob panel and is screwed to said support chassis.

10. A cooker as claimed in any of claims 2 to 9 wherein said brackets are formed from generally T-shaped members, the ends of the T-bar of each T-shaped member being folded towards one another and resiliently engaging a said side wall.

11. A cooker as claimed in claim 10 wherein the tips of said ends engage said side wall obliquely.

12. A cooker as claimed in any preceding claim which is a electric cooker.

13. A cooker as claimed in claim 12 comprising at least one heating element supported in an aperture in said hob panel by a spider member having legs which are all releasable engaged with the perimeter of said aperture.

14. A cooker as claim din claim 13 wherein the legs of said spider member engage in slots or apertures in a downwardly extending wall portion of the hob panel which extends around said first-mentioned aperture.

15. A cooker as claimed in claim 15 wherein at least one of said legs engages a slot or aperture in said wall portion which comprises a locking portion normally engaged by said at least one leg and an entry portion circumferntially spaced from the locking portion and providing access to and from the locking portion for insertion and removal of the spider member, said at least one leg being resiliently biased from the access portion to the locking portion.

16. A cooker as claimed in any of claims 12 to 15 wherein at least one heating element is attached to a conduit assembly, said conduit assembly being releasable located on the underside of said hob panel by cooperating recess and projection configurations formed in the conduit assembly and a downwardly extending wall portion of said hob panel.

17. A cooker as claimed in claim 16 comprising a plurality of heating elements extending from a portion of said conduit assembly, said portion being located by downwardly extending wall portions of said hob panel which surround respective heating elements, said projection and recess configurations being formed in said wall portions and said portion of said conduit assembly.

18. A cooker as claimed in claim 17 wherein side walls of said conduit assembly have complementary profiles to downwardly extending wall portions of said hob panel with which they are respectively engaged.

19. An electric cooker substantially as described hereinabove with reference to Figures 1 to 12, 14 and 15 of the accompanying drawings, optionally as modified in accordance with Figure 13 of the accompanying drawings.