GB2206236A - Switch actuator of variable orientation - Google Patents

Abstract

A membrane-type electrical control panel has a switch (5) beneath a membrane cover (3) and a switch actuator button (7) which is operable through the membrane. The actuator button is preferably in the form of a prism having a triangular or other cross section and, in a first orientation (see Figure 1b), extends through a complementary aperture (6) in a frame member (1) to operatively engage the switch (5). At the mouth of aperture (6) the frame member comprises a recess (8) for retaining the button (7) in a second orientation (see Figure 2b) flush with the frame member out of operative contact with the switch, hence disenabling the switch. Thus, the button may be stored under the membrane (3) within the control assembly so that it can be reused for enabling the switch subsequently, if required. <IMAGE>

Description

Membrane-type Electrical Control Panel This invention relates to an electrical control panel which is suitable particularly, but not exclusively, for use with a photocopying or like machine.

Photocopiers generally include a control panel comprising various switches actuated by buttons or keys which may be depressed by an operator to select particular features required such as, for example, the number of copies to be made, the copy contrast, the magnification, etc.

In existing photocopiers the control panels comprise buttons which protrude through complementary apertures in a moulded plastic plate known as a bezel.

When a photocopier is manufactured it is generally provided with the potential to perform certain functions which may not be required by the customer.

In this situation, the relevant switch(es) may be disenabled at the factory by removing the associated button(s) and replacing the existing bezel with a new bezel having the respective aperture(s) blanked off. The control panel is thus "de-featured". Frequently, the original button and bezel would be discarded.

At a later stage, however, the customer may want the photocopier to be upgraded to perform more functions, in which case the relevant switches have to be re-enabled using a new plastic bezel and button. A set of different bezels has to be kept in stock relating to the various de-featured options of a particular photocopier.

There is a trend nowadays to use control panels, wherein all the switches and actuating buttons are disposed beneath a single membrane cover labelled with the relevant features at the area of the respective buttons. Cost savings are achieved by using membrane labels instead of plastic moulded bezels.

According to the present invention there is provided an electrical control panel comprising switch means beneath a membrane cover, and an actuator button for the switch means operable through said membrane, characterised by means for retaining the actuator button in either one of first and second orientations in which the switch means is enabled and disenabled respectively.

A membrane-type electrical control panel in accordance with the invention has the advantage thatthe actuator buttons, even of disenabled switches, are retained in the control panel assembly at all times which results in a further cost saving since it avoids the need to maintain a stock of spare actuator buttons merely for re-enabling purposes.

In a specific embodiment the actuator button retaining means comprises a frame member having an aperture through which the actuator button may extend in the first orientation to engage the switch means, and a recess at the mouth of the aperture to accommodate the actuator button in the second orientation in spaced relation to the switch means.

Suitably, the aperture and the recess in the frame member are complementary to the actuator button and in the second orientation in which the switch means is disenabled the actuator button is adapted to lie flush with the frame member and therefore provide a solid, flat backing beneath the membrane cover reducing the risk of damage to the membrane at the area of the disenabled feature.

The actuator button is preferably in the form of a prism having a triangular cross section since this configuration is particularly easy to release from the retaining recess.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure la is a broken-away perspective view of part of a control panel in accordance with the invention with the actuator button about to be inserted in the enabled orientation, Figure ib is a sectional view of the control panel with the actuator button inserted in the enabled orientation, Figures 2a is a broken-away perspective view of the part of the control panel in Figures la with the actuator button about to be inserted in the disenabled orientation, and Figure 2b is a sectional view of the control panel in Figure ib with the actuator button inserted in the disenabled orientation.

The control panel herein described is specifically intended for use with a photocopying machine and comprises a frame member 1 having a recess 2 for accommodating a membrane 3 (shown in broken lines in Figures la and 2a) so that the membrane lies flush with the top surface of the frame member. Membranes of this type are conventionally used in contemporary control panels and keyboard applications.

Beneath the frame member 1 is disposed a printed circuit board 4 on which is mounted a conventional switch 5 in known manner.

The frame member 1 comprises an aperture 6 directly above the switch 5. In a plane parallel to the printed circuit board 4 the aperture 6 is triangular in cross section. The aperture 6 accommodates a prismatic actuator button 7 having a complementary triangular cross section.

As can be seen from Figure ib the actuator button extends through the aperture 6 and at its lower end is in operative engagement with the switch 5. At its upper end the actuator button 7 is substantially flush with the top surface of the surrounding frame member 1, although the button 7 may alternatively protrude slightly above the frame member to help visual identification and to permit the operator more positive contact therewith.

The membrane 3 extends over the actuator button 7 and may bear information such as a word or symbol indicating the function of the switch 5. Thus an operator may press the membrane 3 to depress the actuator button and hence operate the switch 5 below.

In practice, a complete control panel would comprise a plurality of switches and button actuators similar to that described above, each controlling a different function of the copier, but all covered by the one single membrane bearing relevant feature information at the area of the respective button actuator to indicate the different functions of the various switches.

Referring now to Figure 2a, when it is required to disenable the switch 5, the membrane 3 is temporarily removed and the actuator button 7 lifted out of recess 6. At the mouth of aperture 5, the frame member 1 comprises a prismatic recess 8 which is triangular in cross section and is complementary to the button actuator 7 in the orientation shown in Figure 2a Having removed the actuator button in the orientation shown in Figure la, it is rotated so that its axis is parallel to the upper surface of frame member 1 as shown in Figure 2a, and is then inserted into the recess 8 such that one of the flat sides 9 of the prismatic actuator button 7 lies substantially flush with the surrounding surface of frame member 1.In this orientation the actuator button 7 is retained out of operative engagement with switch 5 so that when the membrane 3 is replaced, it may be pressed in the area of button 7 without operating the switch. The switch 5 is thus effectively disenabled. If desired, the membrane 3 may be repiaced with a substitute without any feature information at the area of the disenabled switch.

With this arrangement, the button actuator 7 is always retained within the control panel assembly so that when it is desired to re-enable the switch 5 the membrane 3 may simply be removed and the button actuator 7 withdrawn and re-inserted in the orientation shown in Figures la and lb.

It is noted that the triangular cross section allows the actuator button 7 to be removed easily, for example with the aid of a simple levering tool. Also, the recess 8 around aperture 6 permits easy access for removing the button 7 from its enabled orientation. The edges of the button are preferably rounded to facilitate removal.

In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the present invention. For example, the actuator button need not be a prism of triangular cross section, but may for example have a rectangular, square, or semi-circular cross section.

Claims (8)

Claims:

1. An electrical control panel comprising switch means beneath a membrane cover, and an actuator button for the switch means operable through said membrane, characterised by means for retaining the actuator button in either one of first and second orientations in which the switch means is enabled and disenabled respectively.

2. An electrical control panel as claimed in claim 1, wherein the actuator button retaining means comprises a frame member having an aperture through which the actuator button may extend in the first orientation to engage the switch means, and a recess at the mouth of the aperture to accommodate the actuator button in the second orientation in spaced relation to the switch means.

3. An electrical control panel as claimed in claim 2, wherein the actuator button is in the form of a prism.

4. An electrical control panel as claimed in claim 3, wherein the prismatic actuator button is triangular in cross section.

5. An electrical control panel as claimed in claim 3 or claim 4, wherein the actuator button has rounded edges.

6. An electrical control panel as claimed in any of claims 2 to 5, wherein the aperture and the recess in the frame member are complementary to the actuator button.

7. An electrical control panel as claimed in any of claims 2 to 6, wherein in the second orientation in which the switch means is disenabled the actuator button is adapted to lie flush with the frame member.

8. An electrical control panel comprising switch means beneath a membrane cover substantially as herein described with reference to Figures la and ib and Figures 2a and 2b of the accompanying drawings.