FR2492580A1 - Magnetic pushbutton switch in tubular body - defining closed chamber containing magnet actuating movable electrical contacts via its magnetic field - Google Patents

Abstract

The switch has a tubular body (1) in which a permanent magnet (7) is slidable. The magnet is biassed away from one closed end (3) at the body by a coil spring (9a) in the body. An axial actuator rod (6) connected to the magnet projects through the body other end and mounts a push button cap (8) which can be pushed to telescope over the body against a further coil spring (9) inside the cap. Pressing the cap drives the magnet towards the body closed end so that its magnetic field influences a leaf contact (11) of a switch adjacent the body closed end but unconnected to it, closing the switch. Releasing the cap allows the magnet to return to its rest position, allowing the switch to open.

Description

 The present invention relates to control pushbuttons and more particularly it relates to pushbuttons to be used between two different media in which are located, on the one hand, the intervention element to initiate the command and, on the other hand, part, the item to be ordered.

 The present invention is more particularly the case where it is necessary to achieve and maintain a seal between the medium in which the control action is carried and that in which are located the body or bodies to be actively controlled. This is the case, as a rule when it comes to controlling an organ placed in a gaseous or liquid medium different from the actuating medium or in a deleterious, explosive, radioactive medium, etc., with respect to which the operating medium must be protected.

 Some solutions have been proposed to solve the problem above. Thus, it is known to use push-type contactors resiliently biased and comprising a rod mounted with sealing in a support body in which such a rod can be slid. The sealed connection between the body and the rod is provided by means of O-rings which can be mounted either on the rod or in the immobilization housings provided in the support body.

 Such a solution, implemented for many years, is unsatisfactory because the progressive wear of the O-rings does not allow to achieve a durable seal between the two environments.

 The object of the invention is to provide a solution to the technical problem set out above and to propose a simple solution, inexpensive and easy to implement, which allows to consider all possible applications.

 Another object of the invention is to provide a control pusher which is capable, in a very small volume, of achieving a perfect seal between two media at the time of assembly but also over time and thus ensuring,> particularly long and lasting use.

 Another object of the invention is to provide a control pushbutton which can be conveniently made in any size and, therefore, which can receive any possible application from the moment it is necessary to control an organ or'device device in a different medium from that at which the control action is carried.

 To achieve the above aims, the object of the invention is characterized in that it comprises a tubular body delimiting at least one closed bottom chamber containing a control member constituted by a magnet responsible for influencing by magnetic field. the position of a movable actuating member located outside the chamber.

 Various other characteristics of the invention will emerge from the detailed description which follows, made with reference to the accompanying drawings which show, by way of non-limiting examples, several embodiments of the object of the invention.

 Fig. 1 is a sectional elevation of a first embodiment of the subject of the invention.

 Fig. 2 is a cut-elevation illustrating an alternative embodiment.

 Fig. 3 is a sectional elevation showing another embodiment of the device of the invention.

 Fig. 4 is a sectional elevation showing another embodiment of the pusher.

 Figs. 5 and 6 are elevation sections showing two particular states of operation of an alternative embodiment of the example according to FIG. 4.

 According to the first embodiment shown in FIG. 1, the control pusher according to the invention comprises a tubular body I which can be made of any suitable material.

The body I delimits a chamber 2 having a bottom 3 closed and a second bottom 4 open. The chamber 2 contains a movable control member 5, resiliently biased, constituted by a rod 6 mounted with the possibility of sliding through the bottom 4. According to the envisaged manufacturing technique and the nature of the constituent material used, the bottom 4 may be formed by repoussage around the tidë or, still, constituted by a tip mounted and attached to the tubular body I by gluing, welding, screwing, etc ...

 The rod 6 supports a permanent magnet 7 which is slidably mounted inside the chamber 2. Opposite the magnet 7, the rod 6 is associated with an actuating button 8, for example consisting of in the form of a cap surrounding the tubular body 1. For example, the cap 8 may be constituted by an independent piece reported anyway suitable in tiout of the rod 6. An elastic member 9 is associated with the movable member 5, so as to always urge the latter in a stable rest position in which the permanent magnet 7 is away from the closed bottom 3 of the chamber 2.The elastic member 9 may be constituted by a spring, of the helical type of small section, interposed between the open bottom 4 and the cap 8. Another solution, illustrated in phantom in FIG. I, consists in arranging a spring 9a between the closed bottom 3 of the tubular body 1 and the permanent magnet 7.

 Fig. I shows that the control pusher, made in the above form, can be mounted, in any suitable sealed manner, through a support 10, establishing a physical and sealed separation between two media A and B in which are located, d on the one hand, for example an electric switch 11 to be actuated. and, on the other hand, the button or cap 8. According to the targeted technique and the application in question, the connection between the tubular body I and the partition wall 10 can be established by engagement with the press, by screwing, by gluing, welding, etc ...

 The example of fig. 1 relates to the implementation of the pusher of the invention for the control of an electrical switch 11 comprising a blade 12 elastically deformable made of conductive material and secured to a terminal 13. The deformable blade 12 is normally held in position resting open relative to a second terminal 14 on which it must be brought to establish or close an electrical circuit not shown.

 In the rest position illustrated in FIG. 1, permanent laimer 7 * is kept away from the bottom 3 parttl'action of the spring 9 or 9a, so that it has no influence on the state of the deformable blade 12 which represents the body d direct actuation of the switch. When the switch 11 must be controlled, it is sufficient to exert a thrust in the direction of the arrow fl on the button 8, so as to slide in the same direction the movable member 5, against the action permanent spring 9 or 9a which is thus progressively put under higher stress.La magnet 7 is thus close to the bottom 3 which represents a stop limiting the axial sliding amplitude of the movable member 5 relative to the tubular body 1. When the permanent magnet 7 reaches this stop position, the magnetic field that it develops is sufficient to attract the deformable blade 12 which is thus brought into contact with the terminal 14. This results in the closure of the electrical circuit on which is placed the switch 11, as long as the permanent magnet 7 occupies the same position.

 When the action exerted on the button 8 ceases, the spring 9 or 9a restores the stored energy and pushes the movable member 5 in the opposite direction to that of the arrow fl. The permanent magnet 7 is thus progressively moved away from the closed bottom 3, so that the influence of the magnetic field ceases progressively with the distance and, consequently, the deformable blade 12 is normally brought back to its rest position, for example by the elastic memory that it possesses.

 As is apparent from the above, the device of the invention makes it possible to establish a tight separation between the media A and B since the seal between the support 10 and the tubular body 1 is easily achievable with the techniques of known connection and the closed bottom 3 opposes any communication between the two environments.

 This results in a control pusher of great simplicity, high reliability and a constant resistance over time, since the relative displacement members constituting it do not involve a seal or gasket likely to experience wear and tear. rapid deterioration, especially in case of intensive use.

 Fig. 2 shows an alternative embodiment in which the tubular body 1 is made of a conductive material and represents, for example by the bottom 3, the second contact terminal 14a for the blade 12 of the electric switch 11.

 The operation of the above device is identical to that previously described and the bringing of the permanent magnet close to the closed bottom 3 has the effect of exerting such an influence on the blade 12 that it is drawn into contact with said bottom, to establish the closure of the electrical circuit on which it is placed.

 According to a development of the invention, the tubular body 1 is made to include a closed bottom 15, establishing a sealed physical separation between the first chamber 2 and a second chamber 16, coaxial, extending from the bottom 15 constituting the partition separation chamber, opposite the open bottom 4. The chamber 16 is closed by a bottom 17 of the same type as the bottom 4.

 The bottom 17 provides, through a central opening 18, the guiding of a finger 19, made integral with a permanent magnet 20, arranged, with sliding possibility, inside the chamber 16. An elastic member 21 is placed between the permanent magnet 20 and the open bottom 17 so as to always urge the slide thus formed in the direction of the arrow f2, that is to say for which the finger 19 is remote from the elastically deformable blade 12.

According to the arrangement shown, the blade 12 of the switch 11 is intended to be brought into contact with the terminal 14 which is, for example, disposed opposite the bottom 17 relative to the plane of the blade 12.

 According to the invention, the permanent magnet 20 is chosen to have the same polarity as that of the permanent magnet 7 associated with the movable member 5 which is constituted identically to what has been described previously. The magnet 20 and the rod 19 represent an intermediate actuating member.

 In the rest position illustrated in FIG. 3, the moving body 5 is returned to the rest position by the elastic member 9, for example in a stable position in which the permanent magnet 7 abuts against the open bottom 4. Similarly, the elastic member 21 keeps the slider in the rest position in which the permanent magnet 20 is applied or held against the wall or the separation bottom 15.

 When the switch 11 is to be controlled, the movable member 5 is moved in the direction of the arrow fl, so that the permanent magnet 7 is progressively closer to the partition 15. When the magnetic influence between the two elements of the same polarities become sufficient, the displacement in the direction of the arrow f1 of the permanent magnet 7 has the effect of pushing, in the opposite direction to that of the arrow f2> the permanent magnet 20 which causes in its movement the finger 19 made to protrude from the bottom 17 in the direction of the deformable blade 12. When the finger 19 comes into contact with the blade 12, it is moved and brought into electrical contact with the terminal 14. The closure of the circuit remains established both that the initial action in the direction of the arrow f1 is exerted on the button 8 of the movable member 5.

 On the contrary, when this action ceases, the elastic member 9 brings the movable member 5 back into the initial position and, simultaneously, the spring 21 urges the reverse displacement of the slide, so as to return the permanent magnet 20 substantially in abutment against the dividing wall 15.

 In the embodiment described above, and according to the constitution of the switch 11, the body 1 can also be made of any suitable material, even non-conductive, since the action of the finger 19 is only intended to deform the blade 12 to establish its contact with the terminal 14. As previously, it can be expected to play the function of the terminal 14 by the finger 19 and the body 1 which is then made of a conductive material electricity of in order to establish the desired circuit via the support 10.

The object of the invention can find many applications whenever it is necessary to control a device located in an environment physically separate from that at which the control action is to be exerted. The object of the invention finds a preferred application in the case where it is necessary to establish a rigorous seal between the media A or B, for security reasons in particular, because the bottom 3 or 15 establishes, certainly, a tight separation against any transfer even of small importance between the volumes corresponding to media A and
B.

 Among the applications particularly selected, it should be noted that relating to the constitution of a control pusher for quartz watches, that is to say control push functions calculation or even illumination of a such shows. Indeed, the simple but reliable structure allows achievements in small volumes establishing, nevertheless, a perfect seal to dust and liquid fluids. it thus becomes possible to envisage the production of perfectly weatherproof quartz watches in a manner that is sustainable over time, a thing that has never been achieved until now by the known means used to ensure the control of mechanical members in the watches of the classic type.

 It should be noted that according to the characteristics of the permanent magnets chosen, it is possible to envisage by this means a direct actuation control of a mechanical member, such as a lever or a ratchet, with a view to similar application to replace the deformable blade 12.

 Fig. 3 shows that in the particular application to watches, in particular it may be advantageous to give the chamber 2 an axial measurement greater than that of the chamber 16. This makes it possible to have an effective axial stroke of the movable member 5 and, afterwards, represents a safety measure avoiding the unwanted control of the switch 11 as a result of unintentional contact of small amplitude with the button 8. For example, the chamber 2 may have a length twice that of from the bedroom 20.

 Fig. 4 shows another embodiment according to which the control pusher comprises a tubular body la of the same embodiment as that of the flg. 3. In this example, the same references assigned to the subscript a refer to similar constituents.

 According to this embodiment, the chamber 2a contains a control member 5a which is of the fixed type. Sa organ is constituted by an electromagnet 22 adapted inside the chamber and connected by conductors 23 and 24 for example li a cap or lid 25 closing the chamber 2a. The cover 25 carries, for example, a contactor 26 for controlling will power supply of the electromagnet electrical energy from a source of production or distribution not shown.

 In the state according to FIG. 4, the electromagnet 22 is not powered. The spring 21a keeps the permanent magnet 2ta against the partition wall 15a so that the rod 19a does not exert any control action of an electric switch for example.

 When the switch 26 is operated, the electromagnet 22 is energized and creates a magnetic field whose polarity is chosen to achieve a repulsive effect on the permanent magnet 20a.

The bucket slurry is thus displaced, as before, in the opposite direction to that of the arrow f2, so that the rod 19a assumes an actuation control function, for example as described above.

 When the contactor 26 is released, the magnetic field developed by the electromagnet ceases and, as a result, the permanent magnet 20a returns to its rest position under the action of the spring 21a.

 Although this is not shown, it is conceivable that the switch 26 can be made in the form of a push button that can be operated manually.

 Fig. 5 illustrates a development of the example according to FIG. 4. According to this development, the permanent magnet 2ta is extended by a rod 19b having, in its part permanently located outside the bottom 17, two notches 27 spaced by a measurement equal to the stroke of the magnet 20a inside the room 16a.

The notches 27 are intended to cooperate with the complementary end 28 of a leaf spring 29 carried by the bottom 17a. The electromagnet 22 disposed in the chamber 2a is, in this example, connected to a source of electrical energy by an inverter contactor 30.

By way of example, the contactor 30 may be of the double-blade type that can cooperate in two distinct contact positions with, in each case, two of three conductors 31, 32, 33 for feeding the electromagnet.

 In the state according to FIG. 5, the electromagnet 22 is not powered and the magnet 20a is held against the partition wall by the engagement of the portion 28 in the extreme notch 27.

 If in this state, the reversing contactor is placed, for example, in the position according to FIG. 6, the supply of the electromagnet 22 creates a magnetic field that pushes the permanent magnet in the direction of the arrow f3. Under the repulsion force, the spring 29 fades and releases the rod 19a which is axially again immobilized, when the magnet 20a abuts against the bottom 17a, by the automatic engagement of the spring 29 in the corresponding notch.

 This state is maintained even if the inverting contactor 30 is brought back to the neutral position because the breaking of the magnetic field has no influence on the permanent magnet which remains immobilized by the spring 29 and the rod 19a.

 If the reversing contactor 30 is then operated in the second possible position of supply contact, the electromagnet 22 is subject to a reverse supply of the previous one. This creates a magnetic field which produces an attraction effect of the permanent magnet 20a brought back to the first position with erasure and then locking of the spring 29.

 This embodiment represents a pusher type å operating back and forth.

 The invention is not limited to the examples described and shown, since various modifications can be made without departing from its scope.

Claims (9)

CLAIMS:  1 - magnetic control pusher characterized in that it comprises a tubular body (1) defining at least one chamber (2) closed bottom (3) containing a control member (5) constituted by a magnet (7) loaded with influencing by magnetic field the position of a movable actuating member (12) located outside the chamber.  2 - Pusher according to claim 1, characterized in that it comprises a tubular body (1) delimiting at least one chamber (2) closed bottom (3) containing a movable control member (5), resiliently biased in the position of rest and understand  aD a control button (8) accessible from the end of the body opposite the closed bottom and connected to at least one magnet (7) responsible for causing the change of state of an electric switch (11).  3 - Pusher according to claim 2, characterized in that it comprises a movable control member (5) comprising a cap-shaped control knob surrounding the tubular body (1), a rod (6) integral with the button, a permanent magnet (7) axially guided in the chamber of the tubular body (2) and a return spring (9) always returning said member to a rest position in which the magnet is away from the closed bottom of the chamber.  4 - Pusher according to claim 2 or 3, characterized in that the tubular body (1) is made of conductive material and is one of the terminals of the switch (11) influenced by the magnet (7), which is formed by a deformable conductive blade (12) connected to the other terminal.  5 - Pusher according to claim 1 or 2, characterized in that the tubular body (1) defines two coaxial chambers (2-16) separated by a common base (15) closed, one being equipped with the control member (5) and the other containing a movable actuating member formed by a permanent magnet (20) extended by a finger (19) projecting out of the chamber.  6 - Pusher according to claim 5, characterized in that it comprises a tubular body (1) defining two coaxial chambers (2-16) separated by a common bottom (15), the tune containing an actuating member (19). -20) elastic return (21) and the other control member (5) which is constituted by a button (8), a rod (6), a permanent magnet (7) of the same polarity as the magnet permanent member (20) of the actuating member and a return spring (9).  7 - Pusher according to claim 6, characterized in that the chamber (2) containing the movable control member (5) may be longer than the chamber (16) of the movable actuating member (19). 20).  8 - Pusher according to claim 5, characterized in that it comprises a tubular body (1) defining two chambers (2-16a) coaxial separated by a common bottom (15a), one containing a movable actuating member ( 19a-20a) elastic return (21a) and the other, the control member (5) which is constituted by an electromagnet (22) whose power is supplied from a contactor (26) .  9 - Pusher according to claim 5, characterized in that it comprises a tubular body (1) delimiting two coaxial chambers (2-16a), one of which contains a movable actuating member 20a) extended by a rod 09a) cooperating with a locking spring (29) and the other of which contains a control member constituted by an electromagnet (22) able to be fed via a reversing contactor (30).