CONTROL MODULE FOR AN ELECTRONIC DEVICE THAT IS SUITABLE TO WITHSTAND IMPACTS

Description

Technical field of the invention

[0001] The invention falls within the field of electronic devices, and in particular components enabling the control of functions of an electronic device.

[0002] More specifically, the invention relates to a control module for an electronic device adapted to withstand shocks.

[0003] Advantageously, the present invention is particularly suited to portable electronic devices, for example electronic watches. Technological background

[0004] The control mechanisms of electronic devices are generally made up of switches adapted to allow or prevent the passage of a current, enabling, for example, the transmission of a command for the execution of a function.

[0005] In particular, in order to allow or prevent the passage of a current, switches are designed to occupy a rest position and a connection position, in at least one of which they are driven by the action of a user.

[0006] We are particularly familiar with switches comprising a flexible membrane covering an elastic blade adapted to connect terminals together when it is stressed by a user, i.e. when it is under pressure, and to prohibit any connection between the terminals when it is at rest.

[0007] Electronic devices often include a push button designed to be manipulated by the user so as to make contact with the flexible membrane of the switch, via a striker, in order to deform the elastic blade into its connection position.

[0008] When the electronic device is subjected to a shock at the push button, the elastic blade is likely to deform plastically under the effect of the forces applied to it, and consequently, it risks suffering irreversible damage.

[0009] One solution to avoid this problem is to increase the dimensions of the contact surface of the striker so that it distributes the transmitted forces as much as possible in order to reduce the pressure to which the elastic blade is subjected.

[0010] However, this solution may not be feasible for applications where dimensions are critical design constraints, for example in microelectronic or micromechanical fields, such as the watchmaking industry.

[0011] Furthermore, this solution may not be feasible, for example due to manufacturing constraints.

[0012] Another solution is to create an extra thickness in the flexible film. Since this film is generally made of silicone, this extra thickness is designed to deform elastically during an impact in order to absorb the forces.

[0013] However, such an increased thickness is unsuitable for absorbing significant forces, such as those generated by an impact corresponding to a deceleration of 5000G, as specified in NIHS 91-30. Indeed, the flexible film deforms so much under the applied forces that it transmits them to the elastic blade and the terminal, which then deform plastically. US patent 4,207,448 A discloses a control module for an electronic device according to the preamble of claim 1. Summary of the invention

[0014] In order to resolve the aforementioned drawbacks, the present invention relates to a control module for an electronic device according to claim 1.

[0015] It should be noted that, in the present invention, the switch can therefore advantageously be a standard component available commercially.

[0016] In particular embodiments, the invention may further comprise one or more of the following features, taken individually or in all technically possible combinations.

[0017] In particular embodiments, the shock absorber has the shape of a disc.

[0018] In particular embodiments, the switch includes connection terminals and an elastic blade fixed to the frame, the elastic blade being moved into a connection position in which it generates contact between the connection terminals when the switch is in the connection state, and being moved into a rest state in which it prohibits contact between the connection terminals when the switch is in the rest state, the damper being arranged against at least one of the connection terminals so that the latter is interposed between the damper and the striking element.

[0019] In particular embodiments, the pusher comprises a pusher head to which is connected a pusher rod engaged in sliding motion in a guide tube and comprising a free end to which is fixed the striking element, the pusher comprising a spring interposed between the pusher head and the guide tube so as to constrain the pusher to move to a rest position.

[0020] In particular embodiments, the striking element comprises a substantially cylindrical body including a radial dimension extending in a direction orthogonal to the direction of movement of the pusher, said radial dimension being less than the outside diameter of one end of the guide tube at which it is arranged.

[0021] According to another aspect, the present invention relates to a watch comprising a case in which an electronic watch movement is housed, the watch being characterized in that the latter comprises a control module as described above, the pusher being engaged through a case with which the case is fitted and the switch being fixed to a structure of the watch movement. Brief description of the figures

[0022] Other features and advantages of the invention will become apparent from the following detailed description, given by way of non-limiting example, with reference to the accompanying drawings in which: there figure 1 schematically represents a cross-sectional view of a watch case housing an electronic watch movement comprising a control module according to an embodiment not covered by the present invention and a detail view of a switch of the control module; figure 2represents a cross-sectional view of a watch case in which is housed an electronic watch movement comprising a control module according to an example of an embodiment of the invention.

[0023] Note that the figures are not necessarily drawn to scale for reasons of clarity. Detailed description of the invention

[0024] In the example of an embodiment of the invention shown in the figure 2 and described in this text, the invention is applied to the field of watchmaking. In particular, the invention relates to a control module 10 arranged here in an electronic watch movement housed in a watch case, having a case 20, and intended for the control of a function upon request for example from a user.

[0025] As seen on the figures 1 and 2The control module 10 includes a push button 11 that moves in translation along a direction AA and is intended to be activated by the user. In the specific examples shown in the figures, the push button 11 is engaged through the housing 20 so as to be accessible to the user. Alternatively, the push button may be rotationally movable or, more generally, may be actuated by any type of movement.

[0026] The control module 10 further includes a switch 12 intended to be operated by a user upon activation of the push button 11. In particular, the switch 12 is adapted to occupy a connected state and a rest state, the push button 11 being configured to, when it actuates said switch 12, drive it into one or the other of these states.

[0027] As schematically shown in the detailed view of the figure 1In an embodiment not covered by the present invention, the switch 12 may comprise a frame 120 to which are attached an elastic blade 121 made of electrically conductive material and connection terminals 122 and 123. As seen in the detail view of the figure 1 The switch 12 may include a connection terminal called the "central terminal" 122 arranged in the direction of travel of the push button 11, i.e. in alignment with the direction AA, and one or more peripheral terminals 123. Preferably, the elastic blade 121 is configured to occupy, when the push button 11 is activated by the user, a connection position in which it generates a contact between the central terminal 122 and the peripheral terminal(s) 123.

[0028] In particular, when the user presses the push button 11, the latter applies pressure to the elastic blade 121, deforming it into an unstable planar position in which it is in contact with all the central terminals 122 and peripheral terminals 123. The elastic blade 121 is also configured to occupy, when the push button 11 is not pressed by the user, a stable rest position in which it prevents contact between the central terminal 122 and peripheral terminals 123. As can be seen in the detail view of the figure 1 , when in this position, the elastic blade 121 can be bent so as to be prestressed to exhibit elastic characteristics.

[0029] The switch 12 may also include a flexible membrane 124 covering the elastic blade 121, which the push button 11 is intended to press against when activated. However, this flexible membrane 124 is not essential to the invention.

[0030] The pusher 11 includes a pusher head 110 extending outside the case 20 and intended to be operated by the user. The pusher 11 also includes a striking element 111 connected to the pusher head 110 by means of a pusher rod 112 which slides within a guide tube 113 fixed in a through opening in the case 20. For example, the striking element 111 is screwed into the pusher rod 112, or is fixed by any suitable means within the reach of a person skilled in the art.

[0031] The guide tube 113 has, at one end, a first portion by which it is engaged in the through opening of the case 20, and has, at a second end, a second portion having a larger outside diameter than the first portion so as to form a shoulder with the latter. As shown in the figure 1 The guide tube 113 is arranged to bear against the frame 20 by means of this shoulder. The pusher 11 includes a spring 114 working in compression, interposed between the pusher head 110 and the shoulder of the guide tube 113 so as to constrain the pusher 11 to move into a rest position.

[0032] As illustrated on the figure 1 , the striking element 111 rests against the first end of the guide tube 113 when the pusher 11 is in its rest position.

[0033] The striking element 111 comprises a substantially cylindrical body including a radial dimension extending in a direction orthogonal to the direction AA, said radial dimension being advantageously less than the outside diameter of the first portion of the guide tube 113. This feature makes it easier to assemble the striking element 111 onto the pusher stem 112, insofar as it can be carried out before the pusher 11 is fixed to the case 20 of the watch, i.e. before it is engaged in the through opening of said case 20.

[0034] In the example implementation shown on the figure 1 , the body of the striking element 111 has a bearing surface intended to apply, directly or indirectly, pressure on the elastic blade 121 when the pusher 11 is stressed by the user, in order to cause its deformation until it occupies the connection position.

[0035] Advantageously, the control module 10 includes a damper 116 configured to absorb a portion of the forces involved when the push button 11 actuates the switch 12, by deforming elastically, at least when said forces exceed a predetermined threshold. The damper 116 is therefore made of an elastically deformable material, such as an elastomer, or has an elastically deformable structure, such as a compression spring.

[0036] In the example implementation shown on the figure 1The damper 116 is arranged on the bearing surface so as to be subjected to compression against the switch when the striker moves the switch 12 to its engaged or unengaged state. Specifically, when the push button 11 is activated, the damper 116 applies pressure to the switch 12 to move it to its engaged or unengaged state. In this embodiment, the damper 116 is preferably in the form of a disc with a thickness suitable for absorbing a significant portion of the forces involved while transmitting another portion of these forces to the switch 12 to change its state.

[0037] In the example of an embodiment of the invention shown on the figure 2, the damper 116 is arranged between the structure 21 of the watch movement and the switch 12, in the extension of the direction AA; the switch 12 is thus interposed between the damper 116 and the pusher 11. In other words, the damper 116 is arranged at the rear of the switch 12, against it, if we consider that the front of the switch 12 is opposite the pusher 11.

[0038] Thus, if the switch 12 was subjected to excessive forces, it would be able to transmit part of these forces by moving or deforming locally slightly in the damper 116 which would absorb part of the forces transmitted by the switch 12.

[0039] The invention is described in the context of its application to an electronic device, namely a watch. However, it is understood that the invention is not limited to this application and could be advantageously used with any other portable or non-portable electronic device.

[0040] More generally, it should be noted that the implementation and realization methods considered above have been described as non-limiting examples, and that other variants are therefore conceivable.

Claims

1. Control module (10) of an electronic appliance comprising a push-piece (11) comprising a striker element (111), and a switch (12) adapted to occupy a connected state and an idle state, said striker element (111) being configured to drive the switch (12) into the connected state or into the idle state when the push-piece (11) is acted on, the control module (10) furthermore comprising a shock absorber (116) configured to absorb, by deforming elastically, a part of the forces involved when the striker element (111) drives the switch (12) into the connected state or into the idle state, at least when said forces are above a predetermined threshold, the control module (10) being characterised in that the shock absorber (116) is intended to be arranged between a structure (21) of the horological movement and the switch (12), in line with the direction of travel of the push-piece (11), and in that the switch (12) includes a frame (120) against which the shock absorber (116) is arranged in abutment so that said switch (12) is interposed between the striker element (111) and said shock absorber (116).

2. Control module (10) according to claim 1, wherein the shock absorber (116) is in the form of a disc.

3. Control module (10) according to one of claims 1 or 2, wherein the switch (12) comprises connection terminals (122, 123) and an elastic blade (121) all secured to the frame (120), the elastic blade (121) being moved into a connection position in which it gives rise to contact between the connection terminals (122, 123) when the switch (12) is in the connection state, and being moved into an idle state in which it prevents contact between the connection terminals (122, 123) when the switch is in the idle state, the shock absorber (116) being arranged against at least one of the connection terminals (122, 123) so that the latter is interposed between the shock absorber (116) and the striker element (111).

4. Control module (10) according to one of claims 1 to 3, wherein the push-piece (11) comprises a pusher head (110) to which a pusher rod (112) slidably engaged in a guide tube (113) is connected and comprising a free end to which the striker element (111) is secured, the push-piece (11) comprising a spring (114) interposed between the pusher head (110) and the guide tube (113) so as to force the push-piece (11) to move towards an idle position.

5. Control module (10) according to claim 4, wherein the striker element (111) includes a body with a substantially cylindrical shape comprising a radial dimension extending in a direction orthogonal to the direction of movement of the push-piece (11), said radial dimension being less than the outside diameter of an end of the guide tube (113) at which it is arranged.

6. Watch comprising a case in which an electronic horological movement is housed, the watch being characterised in that it includes a control module (10) according to one of claims 1 to 5, the push-piece (11) being engaged through a middle (20) with which the case is provided and the switch (12) being secured to a structure (21) of the horological movement.