FR2616560A1 - Arrangement especially for a slim multi-function keyboard - Google Patents

Abstract

The invention relates to an arrangement especially for multi-function keyboards. This arrangement is characterised in that a part of the movable control element 5 is produced from a light-diffusing material, in that a recess 13 is formed in the support 7 at the periphery of the passage 6 for guiding the element 5 and in communication with the latter, in the region of the part made of light-diffusing material of the element 5, a light source 14 such as a light-emitting diode is placed in this recess 13 so that its light ray is oriented perpendicularly to the axis of the control element 5 and can penetrate laterally into the latter so as to light up the said part uniformly. The invention relates to slim multi-function keyboards.

Description

 The present invention relates to an arrangement in particular for a multifunctional keyboard of small thickness, comprising at least one mobile control member guided in a passage drilled in a support such as a plate and intended to close an electrical contact under the effect of pressure. exerted on the movable member, such as a contact provided on the surface of a plate carrying a printed circuit.

 The known arrangements for thin multifunctional keyboard, of the type which has just been stated, do not allow on the control member light indications as to their functions and, where appropriate, their control state.

 The present invention therefore aims to overcome this drawback.

 To achieve its object, the arrangement according to the invention is characterized in that at least part of said movable member is made of a light-diffusing material, that a recess is made in the support at the periphery of said guide passage and in communication with it, at the level of the light-diffusing material part of the movable member, that a light source such as a light-emitting diode is placed in this recess so that its light ray is oriented perpendicularly to the axis of the control member and can penetrate laterally therein to uniformly illuminate this part.

 According to an advantageous characteristic of the invention, the movable member has a substantially cylindrical shape and the light source is placed so as to be able to penetrate through the edge thereof.

 According to another advantageous characteristic of the invention, the light-diffusing material constituting the movable member is chosen from the family of polyamides.

The invention will be better understood, and other objects, characteristics, details and advantages thereof will appear more clearly during the explanatory description which follows, made with reference to the appended schematic drawings given solely by way of example illustrating a embodiment of the invention, and in which
FIG. 1 is a perspective view of a multifunction keyboard arranged according to the present invention, and
- Figure 2 is a sectional view with cutaway, along line II-II of Figure 1.

 Referring to FIG. 1, it can be seen that a multifunctional keyboard arranged according to the present invention comprises on its control front face a number of control zones which are provided with luminous indications relating to their function or to their state of control or operation.

 Figure 2 illustrates the arrangement that achieves this particular effect. A multifunctional keyboard according to the present invention comprises for this purpose from the front control face towards the rear face of the keyboard a plate 2 forming a finger guide and provided with an orifice 3 delimiting the control area 1, a film 4 made of flexible material. , slightly deformable, for example polycarbonate, and a movable control member 5 which is guided in a passage 6 drilled in a support plate 7 and carries on its rear surface a control end piece 8 which closes an electrical contact, when the member 5 is pressed, this contact being made in the form of a cup 9 provided on the front surface of a plate 10 carrying a printed circuit. In the pressed state of the control member 5 the cup is crushed and established an electrical circuit between one or more zones at its periphery and a central part. An interlayer 11 is disposed on the printed circuit board 10 and is covered with a flexible film 12 made of an electrically insulating material, such as polyester.

The insert 11 is cut at the cup 9 to allow the action of the member 8 thereon.

 In the example shown, the control member 5, of substantially cylindrical shape, is made of a light-diffusing material. This material is advantageously chosen from the family of polyamides.

The support plate 7 has at the periphery of the movable member 5 and in communication with the guide passage 6 thereof a recess 13. A light source such as a light-emitting diode 14 is placed in this recess 13 so that its light ray enters the mobile light-diffusing member 5, through the edge, namely the peripheral cylindrical surface of the latter. The recess 13 extends from the rear face of the support plate 7 but passes through it entirely through this plate.

 The keyboard according to the invention can be designed so that the diffuser member 5 moves only slightly, for example 0.4 millimeters, under the effect of a control pressure exerted on the film 4 forming the front face in the control zone delimited by the opening 3 in the finger guide 2.

During this race, the control member 5 can be swept by the light ray emitted by the diode 14 connected to the printed circuit.

 It is easily understood that the specific arrangement according to the present invention allows uniform lighting of the movable member 5 throughout the part made of diffusing material. Of course the member 5 can be made up as a whole by this material. It is thus easy, by providing on the front surface of the movable member suitable covers to ensure that each control zone bears a light indication relating to its function and / or its operating state, as is apparent from FIG. 1 Despite the presence of the light source 14, a keyboard according to the invention can have a very small thickness, for example of the order of 3 to 15 millimeters, depending on the dimensions of the diodes and the finger guides.

Claims (3)

 1. Arrangement in particular for a multifunctional keyboard of small thickness, comprising at least one mobile control member (5) guided in a passage (6) drilled in a support (7) such as a plate and intended to close an electrical contact under the effect of a pressure exerted on the movable member (5), such as a contact provided on the surface of a plate (10) carrying a printed circuit and located on the rear side of the keyboard, characterized in that at at least a part of said movable member (5) is made of a light-diffusing material, that a recess (13) is made in the support (7) at the periphery of the guide passage (6) and in communication therewith , at the level of the light-diffusing material part of the member (5), a light source (14) such that a light-emitting diode is placed in this recess (13) so that its light ray is oriented perpendicular to the axis of the control member (5) and can penetrate laterally therein for lightning er said part uniformly.  2. Arrangement according to claim'l, characterized in that the material constituting the movable control member (5) is chosen from the family of polyamides.  3. Arrangement according to one of claims 1 or 2, characterized in that the front surface of the part of light-diffusing material of the movable control member (5) is covered with a cover having recesses corresponding to indications associated with the mobile organ.