FI98004C - Selector switch - Google Patents

Abstract

The invention relates to a mechanically actuated switch. The switch comprises an operating lever (1) provided with an actuating cam (2) and a switching member (8), the latter fixed to a support (4), which contains a plurality of microcontacts (15). It comprises means of moving the operating lever (1) so that the actuating cam (2) can actuate at least two of these microcontacts (15) in succession. <IMAGE>

Description

98004 5

This invention relates to a mechanical selector switch.

Switches of this type usually include a rotatably or movably movable control lever and a coupling member. This member includes fixed contact elements and a shaft driven by a control lever, to which are attached movable contact chain elements which can always be brought into contact with certain fixed contact elements. The mechanism by which the interaction of these two types of contact elements is achieved determines the space required by the member. In certain highly integrated devices, this space requirement is too large for the space constraints of the device.

In addition, if a good seal is desired for the coupling, seals must be used in the coupling element in the path of the shaft, which will reduce the operational reliability of the device.

From the article "Sliding selector switch" in IBM Technical Disclosure Bulletin, Vol. 22, no. 6, November 1979 (page 2324), a selector switch corresponding to such requirements has become known. However, this switch, which includes a drive cam attached to the control lever for acting with the microcontacts, includes relative movement of this cam in a direction perpendicular to the plane defined by the microcontacts.

30 The substructure formed by the control lever and the operating cam is thus a mechanical body subject to certain stresses, in particular elastic ones.

Thus, it is an object of the present invention to provide a low-volume selector switch which has a high tightness and in which this substructure is substantially simpler.

The selector switch according to the invention comprises a control lever and 2 98004 switching means fixed to the base and provided with a plurality of microcontacts, the control lever further having at least one operating cam and the selection switch further comprising means for moving the control lever characterized in that the coupling member is implemented by bubble button technology and that the operating cam moves at the same distance from the base at all times.

10

In addition, notches are placed in the base of the selector switch, and the guide lever has a cursor device which cooperates with the notches so that the operating cam stops at the microcontactors.

15

In the first embodiment of the selector switch, the control lever rotates.

In another embodiment of the selector switch, the control lever 20 moves movably.

In addition, each microcontact of the selector switch is covered by a bubble.

25 In one variation of the selector switch, the microcontacts are covered with a uniform cover.

According to a further feature of the selector switch, the electrical conductors connected to the microcontrollers are connected to a comb 30 adapted to be connected to a ribbon cable connector.

The various objects and features of the invention will become more apparent from the following description of embodiments thereof, which, however, is not intended to limit it in any way, and which is carried out with reference to the accompanying drawings, in which: li 3 98004

Figure 1 is a sectional view of a rotary switch according to the invention;

Figure 2 is a plan view of the switch of Figure 1; 5

Figures 3A and 3B are cover and sectional views, respectively, of a unitary cover;

Figure 4 shows an alternative embodiment of the rotary switch-10;

Figure 5 is a sectional view of a linear switch; and

Figure 6 is a plan view of this linear switch.

15

In different figures, the same elements are denoted by the same reference numerals.

The selector switch shown in Fig. 1 and seen from above in Fig. 2 comprises a knob-type control lever 1 provided with a drive cam 2. This knob is fixed to the shaft 3 by glue, screwing or in any other known manner, and the shaft is connected to the base 4 by a flange 5 and can twist it. The knob also includes 25 ball-type alignment devices 6 which can engage the notches 7 of the base 4. The switch further comprises a coupling member 8 fixed to the base 4.

In the first embodiment, the switching member is implemented by a known bubble button technique, as previously used in particular in the manufacture of keyboards.

It comprises an active layer 9, on the upper surface of which an outer layer 10 provided with bubbles 11 is attached, and on the lower surface an attachment layer 12, which is provided with an attachment 35 on the upper surface of the base 4. The bubbles 11 are arranged in a circle with a radius equal to the distance separating the drive cam 2 from the axis of the guide knob 1.

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The active layer 9 comprises a microcontact 15 in the middle of each bubble 11, which makes electrical contact between the two electrical conductors 16, 17 when the operating cam applies pressure to the Bubble perpendicular to the plane 5 of the substrate 4. When the bubble is released from the pressure, the contact opens due to the elasticity of the bubble. The conductor array of microcontacts is connected to a comb 18 which is connected to a flexible ribbon cable. This type of connection is also known in connection with the manufacture of keyboards.

10

In the second embodiment of the coupling member shown in Fig. 3, the principles of the previous structure are applied, except for the structure of the outer layer 10. This layer now does not contain bubbles but a uniform, cut-ring-shaped cover 20, the axis of symmetry of which coincides with the axis of the control knob 11. The microcontacts 15 are arranged on a circle having a radius substantially equal to the central radius of the cut ring 20, the center of which coincides with said axis of symmetry. This cut ring 20 20, like the bubbles 11, is made by thermoforming.

In the two embodiments described above, the tightness is provided by a bubble film type system because, unlike in known devices, the coupling member 25 has no mechanical contact with the external component. The connection takes place via pressure. In addition, the space taken up by the coupling member is limited to the thickness of the film.

In the third embodiment of the coupling member, the microcontactors 15 are not integrated in the membrane, but are conventional microcontactors mechanically attached to the substrate 4 according to the arrangement described above. Although this structure requires more space, it has the advantages associated with conventional microcontactors.

In the three cases described above, the coupling member 8 and the control knob 1 are located on the same side of the base 4.

35 li 5 98004

In the alternative embodiment shown in Figure 4, they are located on opposite sides of the base. The figure shows only the essential parts of the device. The ball 6 and the notches 7 can be located on either side of the base 4 anywhere.

In the various examples shown above, the control knob is provided with a single operating cam. Without departing from the scope of the invention, it may include several of them.

10

The invention has been described in connection with a rotary switch. It can also be applied to a linear coupling as shown in section in Figure 5 and in plan view in Figure 6. The base 4 has a groove 30. The flange 5 of the guide knob shaft 3 15 is positioned so that the knob remains substantially in contact with the base 4 and can slide in the groove 30. Microswitches 15, the bubbles 11 and the notches 7, the operation of which here is the same as in the rotary switch, are arranged parallel to the groove 30 so that each non-rotating guide knob 1 acts appropriately on each basic contact. In the same way as in the case of a rotary switch, where the bubbles can be replaced by a cut ring, they can be replaced here by a piece like a cut cylinder. The groove 30, which is straight in Figure 6, may also be curved in shape without departing from the scope of the invention.

Claims (7)

98004 A selector switch comprising a control lever (1) and a coupling member (8) fixed to the base (4) and provided with a plurality of microcontacts (15), the control lever (1) having at least one operating cam (2) and the selector switch comprising further means for moving the control lever (1) so that the drive cam (2) can act on at least two microcontacts (15) in succession, characterized in that the coupling member (8) is implemented by bubble button technology and the drive cam moves at the same distance from the base. Switch according to Claim 1, characterized in that notches (7) are arranged in the base (4) and in that the guide lever (1) has a cursor device (6) which cooperates with the notches (7) so that the operating cam ( 2) stops at at least one microcontact (15). Switch according to one of the preceding claims, characterized in that the control lever (1) rotates. Switch according to Claim 1 or 2, characterized in that the control lever (1) moves movably. 25 Switch according to one of the preceding claims, characterized in that each microcontact (15) is covered by a bubble (11). Switch according to one of Claims 1 to 4, characterized in that all the microcontacts (15) are covered by a unitary cover (20). Switch according to one of the preceding claims, characterized in that the electrical conductors (16, 17) connected to the microcontactors (15) are connected to a comb (18) which is adapted to be connected to a ribbon cable connector. Il 98004