GB2246196A

GB2246196A - Optical interface between a control member and an electric circuit switch

Info

Publication number: GB2246196A
Application number: GB9015564A
Authority: GB
Inventors: Jean Fran Ois Charles
Original assignee: TECHNIPHONE
Current assignee: TECHNIPHONE
Priority date: 1989-05-30
Filing date: 1990-07-16
Publication date: 1992-01-22
Anticipated expiration: 2010-07-16
Also published as: FR2647947A1; GB9015564D0; FR2647947B1; GB2246196B

Abstract

An optical interface between a control member such as a push-button (2) and an electric switchable device (5) with open and closed circuit states comprises a light emitter (6), a light receiver (7), and a member (9), displaceable by said control member between a position in which a zone 11 permits light from the emitter (6) to reach the receiver (7) to put the device (5) into one state, and a position where a zone 10 prevents light reaching the receiver (7) to put the device into the other state. The zone (10) may be non-reflective or may block transmission between a confronting emitter/receiver pair. The zones 10 and 11 may be cylindrical and the surface on which the emitter and receiver are mounted may be part- cylindrical. The system is usable with intercommunication systems on board an aircraft. <IMAGE>

Description

Interface system between a control member such as a push-button and a device for closing and opening an electric circuit.

The present invention relates essentially to an interface system between a control member such as a push-button and a device for closing, making or switching on and for opening, breaking or switching off an electric circuit, of the kind comprising a switchable device with two states corresponding to the open and closed states, respectively, of said electric circuit, which comprises two elements the putting in communication and the isolation of which are representative of both states of the switchable device and a switching member which carries means for putting in communication and isolating said elements of the switchable device and is displaceable by said control member between a position for putting said elements in communication and a position for isolating these elements.

There are already known interface systems wherein the switchable devices with two states comprise electric contacts for instance an open circuit or rest contact and a closed circuit or making or operating contact and the switching member carries the corresponding movable so-called sliding electric contact, the rest and make contacts being shaped as pliers, clips or like claps.

Such a system suffers from great inconveniences. As to the switched information it is mandatory te make them transit through the contacts of the interface thereby generally involving a diversion of the switched information between their starting point and their arrival point. As to the contacts themselves it appears tha their major drawbacks are the deformation of the pliers, clips or clamps, their wear, the impairment with time of the electric performances of the contacts such as their resistance and insulation and a bad behaviour under vibrations.

The main object of the present invention is to provide an interface system which removes the inconveniences of the known systems.

To reach that goal the interface system according to the invention is characterized in that the switchable device is a device wherein the putting in communication or the isolation of said elements occurs according as the switching member is in a coupling position without any mechanical contact in proximity of these elements or assumes a position remote therefrom.

According to an advantageous characterizing feature of the invention the switchable device is an opto-coupler comprising light emitter and receiver elements and the switching member carries means adapted to allow or to prevent the receiving by the receiver element of the light emitted by the emitter element according as the member is in either one of its two positions.

According to another advantageous characterizing feature of the invention the emitter and receiver elements are arranged so as to prevent a direct receiving by the receiver element of the light emitted by the emitter element and the switching member carries in aligned relation to the direction of its displacement a light transmission zone or range between both elements and a non-transmission zone or range.

The invention will be better understood and further obJects, characterizing features, details and advantages thereof will appear more clearly as the following explanatory description proceeds with reference to the accompanying diagrammatic drawings given by way of non limiting examples only illustrating several presently preferred specific embodiments of the invention and wherein:: - Figure 1 is a diagrammatic view of a first embodiment of an interface system according to the present in-.-ention; - Figure 2 is a top view with parts broken away of a control box or cabinet enclosing an interface system according to Figure 1 for several push-buttons; - Figure 3 is a view in cross-section taken upon the line III-III of Figure 2; - Figure 4 is a view in cross-section taken upon the line IV-IV of Figure 2; - Figure 5 is a view in cross-section taken upon the line V-V of Figure 3; - Figure 6 is a diagrammatic view showing a second embodiment of the invention; and - Figures 7 and 8 are diagrammatic top view and cross-sectional views, respectively of a third embodiment of an interface system according to the invention.

Figure 1 diagrammatically shows a first embodiment of an interface system 1 according to the invention between a push-button shown at 2 and a device 3 for opening or closing an electric circuit 4. The device 3 could be of any suitable known type for instance a transistor or like semiconductor device or a relay. In this first embodiment the interface comprises a switchable device with two states which consists of an opto-coupler 5 comprising light emitter and receiver diodes 6 and 7 and a switching member shown at 9 which is displaceable by the push-button 2 between two positions shown in solid and chain-dotted lines, respectively, in which the switching member allows or prohibits the receiving by the emitter diode 7 of the light emitted permanently by the emitter diode 6 of the opto-coupler.

For that purpose the switching member 9 which is displaceable in the axial direction of the push-button 2 carries two axially aligned zones or ranges, namely a first zone 10 shown in black and adapted to isolate the receiver diode 7 from the emitter diode 6 and a zone 11 adapted to allow the propagation of the light from the emitter diode 6 towards the receiver diode 7.

Wit reference to Figures 2 to 5 is hereinafter described a concrete or practical e.-.bodiment of an interface system according to the invention based upon the principle illustrated on Figure 1.

As shown on Figure 2 the interface system is enclosed within a control box 13 provided on its front face with five push-buttons 2. The interface system is the same for all the push-buttons. The latter are mounted on a yoke rail 14 which extends at the front face of the box 13. The yoke rail exhibits a U-shaped cross-section.

The push-buttons 2 are mounted in the front leg 15 of the yoke 14. For that purpose the front leg 15 is formed with a thoroughfare hole for each push-button through which the latter extends with an inner portion forming a cylindrical tubular end part 16 within the inner space of the yoke or clevis. On this end part 16 is fitted a slide 17 which forms the switching member 9 of Figure 1. This slide while allowing the rotation of the push-button 2 is a movable in the axial direction only of the button owing to a radial pin 19 which is screwed into the outer surface of the slide and extends within a guide slot 20 formed in the base wall 21 of the clevis or yoke at right angles ço the center line axis thereof, i.e. in the axial direction of the push-button 2.The rail leg 22 of the yoke or clevis 14 is provided in axial relation to each opening in the front leg with a circular bore through which extends along the center line axis of the corresponding push-button 2 the rotary axis or shaft 25 of a member for varying an electric value such as a potentiometer shown at 26. The shaft or axis 25 exhibits an axial slot 26 which diametrally extends through this axis or shaft. The latter extends in coaxial relationship into the inner space of the end part 16 of the button 2 and is made fast in rotation with the latter by a pin 29 diametrally mounted into the end of the end part 16. A coil spring 31 is mounted in coaxial relationship about the rotary shaft 25 and bears with one end onto the inner face of the rail leg 22 of the yoke and with its opposite end upon a shoulder surface 32 of the slide 17. Since the latter bears in axial relationship with its forward front face upon a radial shoulder surface 33 of the end part 16 of the push-button and the latter exhibits a collar or flange 35 in engagement with its outer radial face with the inner face of the front leg 15 of the yoke or clevis 14, the spring 31 would keep the slide 17 and the push-button in their relative axially interlocked position and thus constitutes a means for returning or moving the push-button back into its outwards extended position. It should further be pointed out that the axial slot 27 in the shaft 25 of the potentiometer 26 has a length allowing the push-button 2 to be depressed or driven inwards.

Referring in particular to Figures 3 to 5 there is seen that a plate with printed circuits 37 is mounted on the yoke rail 14 at the free ends of its leg walls 15 and 22. This plate 37 exhibits the opto-coupler 5 of Figure 1 on its lower surface located inside of the yoke 14. This opto-coupler is arranged with respect to the slide 17 in a way which will be described hereinafter by disclosing the structural details of the slide. It is moreover seen that the potentiometer 26 is also mounted onto the inner face of the plate 37.

As shown on Figures 2, 3 and 5 the slide 17 exhibits in its flat face in front of the plate 37 a parallelepiedic recess .38 which is open at the free end of the slid. This recess 38 is divided into two axially aligned zones 40 and 41. Both zones exhibit each one an axial leng h which corresponds to the size of the opto-coupler 5 (as shown in particular on Figure 2). The zone 41 which is located towards the end of the slide is covered over its whole inner surface with a black layer or coating whereas the inner surface of the zone 40 is adapted to reflect the light.The opto-coupler 5 is arranged below the plate 37 so that its surface in front of the slid on which are located the light emitter and receiver dudes 6 and 7 is in front of the black zone 41 when the psh-button 2 is in its outwards extended position as shown for the button located on the left-hand side on Firre 2. Under these conditions the light emitted by the emitter diode may not reach the receiver diode. On the contrary when the push-button is depressed like the button located on the right-hand side of Figure 2 the opto-coupler is in front of the zone 40 which owing to the reflecting power of its surface would transmit the light between the emitter and receiver diodes.

The operation of the interface system which has just been described appears from the description of the structure thereof. It is easily understood that the slide 17 due to its two zones 40 and 41 axially aligned and shaped as light reflecting and non-reflecting zones, respectively, would cause the opto-coupler to be activated when the corresponding push-button is depressed. In this case an electric current would flow through the circuit of the receiver diode 7 which causes the switching device 3 located in the electric circuit 4 to close. It should be pointed out that irrespective of the axial position of a push-button the latter may be turned to cause the shaft 24 of the potentiometer 26 to be rotated and thus the magnitude of an electric value to be varied.

Figure 6 diagrammatically shows an embodiment of the interface wherein the slide 17 consists of an integral part of the inner portion of the push-button. In this case the surface of the opto-coupler 5 which comprises the emitter and receiver diodes 6 and 7 is of semicylindrical shape and the zones 40 and 41 for transmitting light or isolating the receiver diode, respectively, are directly lying onto the cylindrical inner end part of the push-button.

The zone 40 which prevents the receiving of the light emitted by the emitting receiving 6 by the receiver diode 7 could also be made as a surface shutting both diodes instead of a non-reflecting surface.

Another embodiment of the interface is shown on Figures 7 and 8 wherein the emitter and receiver diodes 6 and 7 are located in confronting relationship at some distance from each other. The switching member is in this case formed of an opaque portion 47 of the push-button 2 which engages the space between both diodes when the button is depressed and is withdrawn from this space when the button is lying in its outwards moved position.

Without leaving the scope of the present invention the switchable device could also be formed of a Hall effect transistor junction. In such a case the switching member could be a magnet.

It appears from the description of the invention which has just been made that the latter provides an interface system which makes it possible from a manual control to act upon a switching member located outside of an intercommunication system for instance on board an aircraft without making use of mechanical contact pieces carrying the electric information or data.

Apart from the fact that in the interface system according to the invention the switchable device and the switching member do not come in mechanical contact with each other it is seen that the switched information or data do not transit through the interface as would be the case in the known interface systems. The system according to the invention brings therefore about a great improvement to the reliability or dependability of the interface.

Claims

CLAIMS:

1. An interface system between a control member such as a push-button and a device for closing and opening an electric circuit, of the type comprising a switchable device having two states corresponding to the open and closed states of said electric circuit, which comprises light emitter and receiver elements and a switching member carrying means adapted to allow or to prevent the receiving by the receiver element of the light emitted by the emitter element according as the switching member is in either one of the two positions, the switching member being displaceable between these two positions by said control member , characterized in that the switching member carries in aligned relationship in the direction of its displacement a zone for transmitting light between both elements and a non-transmitting zone.

2. An interface system according to claim 1, characterized in that said zones are zones with a reflecting surface and with a non-reflecting surface, respectively.

3. An interface system according to claim 1 or 2, characterized in that the switching member is formed of a slide made fast with the push-button for axial motion therewith.

4. An interface system according to claim 3, characterized in that the push-button is rotatable and its end opposite to the operating end is coupled to an element such as the shaft of a potentiometer for varying an electric value of the electric circuit -.respective of the axial position of the button, the slide being possibly mounted in non-rotatable relationship onto said coupled end.

5. An interface system according to claim 4, characterized in that the push-buttor is mounted onto the front face of a supporting yoke forming a part of a control box and advantageously U-shaped and the slide is mounted inside of the yoke onto the inner portion of the push-button underneath a printed circuit plate which carries the device having two switchable states

6. An interface system according to one of the foregoing claims, characterized in that the slide is formed of an integral part of the push-button and is made as an at least partially cylindrical end part carrying on its outer surface zones for transmitting or isolating the light emitted by the diode emitter element and in that the emitter diode and the diode receiver element are arranged within an at least partially cylindrical surface complementary of the surface of the end part of the slide, the push-button being rotatable.

7. An interface system substantially as described herein with reference to and as shown in the accompanying drawings.