GB2312153A

GB2312153A - Electrical appliance with optical indicating means

Info

Publication number: GB2312153A
Application number: GB9707921A
Authority: GB
Inventors: Helmut Kaiser; Franz Bauer; Horst Gschossmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-04-19
Filing date: 1997-04-18
Publication date: 1997-10-22
Anticipated expiration: 2017-04-18
Also published as: GB9707921D0; DE29623763U1; FR2747823A1; GB2312153B; FR2747823B1

Description

2312153 ELECTRICAL APPLIANCE WITH OPTICAL INDICATING MEANS The present

invention relates to an electrical appliance and has particular reference to provision of an optical indication of operation of the appliance.

It is know n in household appliances to provide operational indications by way of small pilot lamps which sit in a housing opening at any part of the household appliance. In that case, the lamp is arranged in the interior of the housing and radiates out from this opening or projects out of the opening beyond the upper side of the housing. It is a disadvantage of optical indications of that kind that they are visible to the user only when the user is in the right position relative to the lamp. Frequently, the lighting-up of the lamp is difficult to recognise in the case of bright sunlight.

In German Utility Model GM 78 20 095 there is described an electrical fondue appliance with a substantially cylindrical housing in which an incandescent bulb is fastened centrally in a lamp holder. The light of the bulb can pass out through openings distributed around the housing circumference. Thus, operation of the appliance is indicated in all directions to persons seated around the appliance. A disadvantage in that case is, however, the poor visibility of the light issuing from the housing as well as the cost and complication caused by the required all round perforation of the housing. There is therefore a need, in an electrical appliance, to provide an operational indication which may be visible all round to a user. 25 According to the present invention there is provided an electrical appliance comprising a housing provided with optical indicating means for 2 indicating an operational state of the appliance, the indicating means comprising optical conductor means substantially completely surrounding the housing and light-emitting means arranged to feed light to the conductor means for issue therefrom to be visible circumferentially Of the housing.

The light emitted by the light-emitting means, for example a lamp or lamps, is conducted by the optical conductor means from the interior of the housing circumferentially outwards to be readily visible to the user. Thus, a clear indication of the operational state can be provided circumferentially with one lamp or a small number of lamps, in which connection the geometric arrangement of the lamp in the housing, the structuring of the interior of the housing and the arrangement of other components of the appliance, for example electronic assemblies, are independent of the constraint represented by rectilinear propagation of light in air. Light exit openings possibly needed in the housing can be closed off by the optical conductor means itself.

Preferably, the optical conductor means projects circumferentially slightly out of the surface of the housing. The extent of this projection is determined on the one hand by the requirement for visibility of the operational indication and on the other hand by the need for protection of the optical conductor means against damage due to mechanical impact. Due to the integration of the optical conductor means into the housing surface, a clearly visible operational indication can be achieved without producing disruptive steps and projections at the surface of the housing.

Advantageously, the optical conductor means displays at least one reflective surface, which substantially completely surrounds the housing 3 and at which a light fed into the optical conductor means from the lamp is reflected outwardly all round from the housing. Consequently, an operational indication which is visible all round can be realised with a single optical conductor. At the reflective surface, light can be guided in such a manner to a boundary surface of the optical conductor that it is radiated by the optical conductor, for example upwardly. Alternatively, the optical conductor can be bent up at its outer circumference towards the user. In order to increase the brightness of the operational indication at a preferred point, the lamp can be arranged in immediate proximity of a part of the encircling reflective surface.

Preferably, the optical conductor means comprises an optical conductor plate, which can if desired serve as a base or partition member of the housing. The optical conductor means is in that case a component of the housing and can, apart from the function of providing an operational indication, assume additional functions otherwise associated with the housing or components of the housing. For example, an otherwise additionally required base part can be dispensed with. Mounting means for the lamp or lamps, for associated electrical connecting elements and for switch elements and the like can be provided at the member. Thereby, the indicating means serving as a base or partition member can then be produced as a separate subassembly. During assembly, for example, the lamp or lamps and the electrical connecting elements can be pre-assembled at the pl ate. The plate is then fastened to the housing, whereby the appliance inclusive of indicating means may be ready for function. When mounting thesubassembly, the connection to the current supply of the lamp or lamps can be produced in particularly simple manner if the contact terminal element is formed to be resilient. This can then compensate for 4 spacing tolerances to the voltage-carrying contacts and ensure a reliable electrical connection of the optical indicating means to the voltage supply available internally of the appliance.

In the case of an appliance with a vapour exit duct in a base region thereof, the optical conductor plate advantageously forms a part of the duct. In addition, the plate can have outlet openings in the region of the duct so as to ensure the running-off of condensation water from the housing. The optical conductor plate serving as a base member thus fulfills additional functions, which further simplifies the overall construction of the appliance. Preliminary assembly and checking of the base subassembly is possible externally of the appliance housing.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a side elevation of an electrical water kettle embodying the invention, in sectional illustration substantially along the line I-I in Fig. 2; Fig. 2 is a plan view of an optical conductor plate serving as a base part of the kettle in Fig. 1; Fig. 3 is an elevation, to enlarged scale and substantially along the line III-III in Fig. 2, of a lamp and an electrical connecting element mounted in the optical conductor plate; Fig. 4 is a plan view of a contact clip for the electrical connection of the two lamps shown on the plate in Fig. 2; Figs. 5a and 5b are schematic detail elevations of modifications of the optical conductor plate; and Fig. 6 is a plan view of 'a luminous ring for the kettle of Fig. 1.

Referring now to the drawings, there is shown a household appliance 1 in the form of an electrical water cooker set down on a pedestal 3. The appliance 1 comprises a tubular casing 5, which converges conically upwards and which has a conical pouring spout 7 and a handle-shaped handle 9 disposed opposite one another. An actuating switch 11 for the appliance 1 is arranged above the handle 9. The upwardly open casing 5 is closed by a circular lid 13. The casing 5 together with an annular skirt 17 and an optical conductor plate 19 of PC plastics material forms a housing 15 of the appliance.

The downwardly conically enlarging end portion of the casing 5 ends in a cylindrical plug portion 21, which extends at an angle therefrom and is slightly offset inwardly. The upwardly narrowing skirt 17 is plugged onto the portion 21 as far as an abutment edge 23. For the reception of the skirt 17 at its lower end portion, an annular groove 25 is formed at the circumference of the optical conductor plate 19. An external, substanti al l y vertically extending wall 27 bounding the groove encompasses the skirt 17 and projects slightly outwards below the outer surface of the lower end portion of the skirt 17 and thereby of the housing 15. Several support feet 29, which are distributed uniformly around the circumference, are formed at the underside of the plate 19. The base of a water vessel of the appliance 1 is formed by a fine steel plate 31, which is bent circumferentially and with the interposition of an annular seal 33 around the lower rim of the portion 25 21 of the casing 5. A substantially closed space 34 is formed underneath the vessel. A connection between the plate 31 and the portion 21 is secured by the inward wall surface of the skirt 17 in this region. A 6 circular aluminium plate 35, which serves as a heat distributor, is fastened at the underside of the plate 31. An annular tubular heating ele"t 37 is welded to the plates 31 and 35. An electrical regulating unit 39 is enclosed by the element 37 and attached to the plate 35 in about the middle thereof. The unit 39 is electrically supplied in a known manner on the setting-down of the appliance 1 onto the pedestal 3 by means of a coupling unit 41 arranged therein. For this purpose, an electrical mains lead 39 extends into the interior of the pedestal 3 and supplies the coupling unit 41 with electrical current. This unit projects, in the form of a dome, in a pedestal dome 45 and through a central circular coupling opening 47 of the plate 19 into the interior of the housing 15 and supplies the regulating unit 39 with the mains voltage when the appliance 1 is placed on the pedestal 3. The heating element 37 is electrically connected with the regulating unit 39 by way of a feed line 49. The regulating unit separates the heating element 37 from the mains current in particular on drying-up of the appliance 1, when the water therein begins to boil or when the appliance is switched off by way of the switch 11.

The plate 19 is drawn upwardly in dome shape in its centre. In this 20 region, it has the circular opening 47, through which the coupling unit 41 projects into the regulating unit 39 and makes contact therewith. In that case, the unit 39 closes the opening 47. Three assembly openings 51 are arranged around the opening 47 in the plate 19 and receive screws for screw-fastening of the plate to the regulating unit 39 thereby the housing base to the housing 15. Two incandescent lamps 55 (Fig. 3) are retained at the optical container plate 19 (omitted in Figs. 1 and 2 for reasons of simplification) in the region between the dome and the annular 7 groove 25. For this purpose, a groove-s haped depression 57 is formed in the plate 19 in immediate proximity of the groove 25. The portion of the depression 57 adjoining the groove 25 is covered by a semi -cylindrical cover 59. The glass bulb 63 of the lamp 55 is plugged through the opening 61 formed thereby. A filament of the lamp 55 (not shown) is in that case retained below an upper side 65 of the plate 19, whereby the coupling of light into the optical conductor is improved.

A cut-out 69 is formed in the plate 19 in prolongation of the depression 57 and towards the centre of the plate 19 and serves for mounting a spring element 67. The metallic spring element 67 has a first resilient portion 71 and a second resilient portion 73, which are connected together by way of a bearing portion 75. The lamp 55 lying in the depression 57 is urged by the first portion 71 into the opening 61 towards the groove 25. In that case, the first resilient portion 71 bears against a vertical wall of the depression 57. The bearing portion 75 of the spring element 67 rests on the upper side 65 of the plate 19. The second resilient portion 73 extends upwardly out of the cut-out 69 away from the plate 19 towards the regulating unit 39. On tightening the plate 19 from below against the regulating unit 39, the upper end portion of the second portion 73 is urged against corresponding electrical contact points of the unit 39 (not shown), whereby the lamp 55 can be supplied with mains voltage.

The two lamps 55 are electrically connected in series by means of a resilient metallic contact clip 81 (Fig. 4) and urged into the depression 57 of the plate 19. The clip 81 is formed in the shape of a flat tape and extends substantially in U-shape. The two end portions 83 are each turned through 90 out of the vertical plane of a middle portion 85 of 8 the clip. Consequently, the middle portion 85 stands on edge on the plate 19, whilst the end portions 83 extend substantially parallel to the plate 19. The clip 81 is guided by a first rib 87 and four second ribs 88 disposed uniformly along the length thereof on the plate 19 and urged against the lamps 55 for electrically conductive connection therewith.

The four second ribs 88 have clamping hooks 89. The first rib 87 arranged in centre, by contrast to the four second ribs 88, does not have a clamping hook. The clip 81 is plugged onto the plate 19 from above and retained between the first rib 87 arranged in the region of the middle portion 85 of the clip and the four second ribs 88 at both sides. It is guided by the ribs 87 and 88 to stand upright on the upper side 65 of the plate 19. The end portions 83 of the clip 81 are urged, by virtue of their resilience, against the sockets of the lamps 55 in that the end portions 83 are hooked, under bias, under the clamping hooks 89 of the two outermost ribs 88.

The light emitted by the lamps 55 propagates towards all sides in the p] ate 19 and i s gui ded by thi s to the outer rim outl ine of the p] ate 19. The wall 27 serves as a light conductor which deflects the arriving light through 90 relative to the substantially horizontal direction of propagation and guides it upwardly for radiation outwardly at the upper end portion of the wall 27. In the variant according to Fig. 5a, a reflective surface 95 is formed circumferentially at the external outline of an optical conductor plate 19a and reflects the light arriving in horizontal direction in this region at least in part upwardly and externally past the skirt 17 so as to be easily visible to a user looking at the appliance from above. Alternatively, as shown in Fig. 5b, the circumferential wall of the plate is formed with a surface serration 97, 9 which provides numerous reflective surfaces.

The incandescent lamps 55 can be arranged at suitable locations on the plate 19 in dependence on the given geometry, the optical conductivity of the optical conductor and the desired lighting behaviour of the plate 19. The number of the lamps 55 can also be varied. Moreover, it will be obvious that, in place of lamps 55, other lightemitting elements, for example luminescent diodes, can be used. Moreover, the operational state indicator can be incorporated in other household appliances, such as coffee machines, egg boilers and the like.

The handle 9 of the appliance 1 is set against the outward wall of the casing 5. It consists of a uniformly curved grip part 99 and a rodshaped functional extension 101. This extends, with substantially Ushaped cross-section, downwardly along the casing 5 and the skirt 17 and together with their outward walls forms a substantially vertically extending hollow space 103, which at its upper end portion has an opening for vapour rising up in the water vessel. A switch rod 105, which is actuable by way of the switch 11 to be displaceable substantially vertically, is accommodated in the hollow space 103. The regulating unit 39 can be actuated by means of the rod 105 by way of a switch arm 107 articulated thereto. The switch arm 107 projects through an opening 109 of the skirt 17 into the space 34. In this region, the course of the skirt 17 departs from the otherwise conically converging annular shape.

The skirt 17 extends inwardly all round directly below the plug portion 21 and has there an opening 109 for the arm 107. The skirt extends below the arm 107 substantially in the form of a base plate 111 out again to the skirt circumference. A vapour passage opening 113 is provided in the base plate 111. A steam-sensing or temperature- sens i ng element of the regulating unit 39 is arranged in the region of the opening 113. A vapour exit opening 115 is formed between the skirt 17 and the plate 19.

For that reason, the plate 19 is shaped in this region, in departure from the rest of its structure as a flat plate without the annular groove 25.

The functional part 101 of the handle covers the skirt 17 as well as the plate 19 in this region. For fastening of the functional part 101 to the plate 19, this has at its lower end portion a fastening arm 117, which extends horizontally and thus parallelly to the plate 19 and which, by means of an elongate opening formed therein, is hooked into a flat bearing rib 119 of the plate 19. In addition, vapour slots 121 are formed in the functional part 101 in horizontal extension of the opening 115.

Vapour arising in the interior of the casing 5 initially rises up, travels downwardly from above through the hollow space 103 of the part 101, then through the vapour passage opening 113, the vapour exit opening and the vapour slots 121 out of the appliance 1. A vapour exit channel 122 is thereby formed. Water condensing can in that case escape through exit openings 123 of the plate 19. In order that the vapour can be conducted reliably out of the appliance 1, a sealing wall 125, which is closed upwardly by a part region of the underside of the regulating unit 39, extends approximately in U-shape on the plate 19. The space 127 thereby formed is open substantially only to the outside by the vapour exit opening 115.

Alternatively, the optical conductor plate 19 can be formed in two parts. A plate-shaped base part 200 closes the appliance 1 downwardly, whilst an open luminous ring 201 of optically conductive material is retained at the base part 200. The luminous ring 201 has a flat annular body plate 203, from the upper side of which a narrow rim 205 extends circumferentially upwards. At the upper side of the plate 203, two sets of four wedge-shaped optical conductor wedges 207 are formed one behind the other within the rim 205. An encircling groove 209 for the reception of the lower end portion of the housing 15 or of the skirt 17 is formed between the outer side surface of the wedges 207 and the inward surface of the rim 205. Openings, into which respective lamps 213 are plugged, preferably light-emitting diodes, are provided at the end faces 211 of the wedges 207. The light fed tangentially into the wedges 207 by the lamps 213 is so reflected at reflective surfaces 215, which are formed by the inner side surfaces, of the wedges 207 that light is radiated radially outwards along the luminous ring 201. The ring 201 is subdivided into the eight optical conductor wedges 207 so that an adequate circumferential radiation of light is achieved.

Claims

1 An electrical appliance comprising a housing provided with optical indicating means for indicating an operational state of the appliance, the indicating means comprising optical conductor means substantially completely surrounding the housing and light-emitting means arranged to feed light to the conductor means for issue therefrom to be visible circumferentially of the housing.

2. An appliance as claimed in claim 1, wherein the optical conductor means projects outwardly of the circumference of the housing.

3. An appliance as claimed in claim 1 or claim 2, wherein the optical conductor means has at least one reflective surface which substantially completely surrounds the housing and reflects light from the lightemitting means outwardly of the housing.

4. An appliance as claimed in claim 3, wherein the lightemitting means is arranged in the immediate proximity of part of the reflective surface.

5. An appliance as claimed in any one of the preceding claims, wherein the optical conductor means comprises an optical conductor plate forming a base member or partition member of the housing.

6. An appliance as claimed in claim 5, wherein the plate is provided with mounting means mounting the light-emitting means and electrical connecting means for the light-emitting means.

13

7. An appliance as claimed in claim 6, wherein the electrical connecting means comprises a resilient contact element.

8. An appliance as claimed in any one of claims 5 to 7, wherein the appliance is provided in a lower region thereof with a vapour outlet duct, the duct being defined in part by the plate.

9. An appliance as claimed in claim 8, wherein the plate is provided with water outlet openings in the region of the duct.

10. An appliance as claimed in any one of claims 5 to 9, wherein the plate together with components carried by the plate forms a subassembly 10 connected to the housing.

11. An electrical appliance substantially as hereinbefore described with reference to the accompanying drawings.