ELECTRIC SWITCH WITH SINGLE ROTARY AND AXIAL ACTUATION MEMBER

Abstract: The invention proposes a rotary electric switch (10) also having axial actuation of the type comprising a single actuation member (36) which is mounted rotatably and axially slidingly along its axis of rotation (A), in a housing (13) of the switch, in such a way as to rotate an upper coding wheel (52) which cooperates with a first series (70, 72, 80, 82) of contact elements carried by the housing (13), and in such a way as to constitute the axial control member for the triggering of an elastically deformable lower conductive element (100), from a stable rest position, so that it cooperates with a second series (102, 104, 110) of fixed contact elements carried by the housing (13), and of the type in which an upper span (40) of the single actuation member (36) is guided in rotation and in axial sliding, in a complementary upper part (12, 18) of the housing (13), characterized in that the lower end span (44) of the single actuation member (36) runs axially downwards through the lower conductive element (100, 120) and is guided in rotation and in axial sliding in a complementary lower part (14, 46) of the housing (13).

Description: "Electric switch with single rotary and axial actuation member" The present invention relates to a rotary electric switch also having axial actuation. The invention relates in particular to an electric switch making it possible for example, by means of a single actuation member, to perform separate electrical switching operations with a view in particular to controlling a function of an electronic apparatus subsequent to a prior choice made by scrolling a menu or a list on a d isplay screen . Such a function must for example be provided for in a portable telephone set which comprises means allowing for example the user to store in a reg ister a series of telephone numbers which he can then call directly without having to d ial the other party's number on the keypad . For this purpose, the telephone comprises a display screen on which the user can scroll, in two opposite scrolling directions, the list of parties, each with his previously stored number. Accord ing to a known design , this d rop-down d isplay operation requires two electric switches one or other of which the user presses, via separate pulses or continuously, so as to scroll the list in one or other of the two scrolling directions. Once the user has selected the party whom he wishes to call, he must then enable this selection and instigate the automatic dial-up calling operation by acting on a third electric switch . This design therefore necessitates the provision of three electric switches which , in the known products, are constructed in the form of separate components which must be mounted on a printed circuit board of the telephone. Such solutions are therefore particularly expensive in that they call upon a large number of components, in that they make it necessary to mount the components, for example by flat transfer, on the printed circuit board and in that, for each switch, they make it necessary to call upon a separate actuation button. Moreover, the function of selecting and calling a stored number must be as ergonomic as possible as far as the user is concerned. I ndeed , it is especially desirable for the user to be able to manipulate his telephone set with one hand , that is to say with the hand with which he holds his telephone. For this purpose, it has already been proposed that the various switches be arranged along one of the lateral edges of the telephone so that the user can manipulate them with one or more fingers. It is however, readily understood that it is necessary to place the three switches in an adjacent manner so that the corresponding actuation buttons are situated close together so as to ease the manipulation by the user, without the latter having to move his hand with respect to the portable telephone. Such an adjacent layout of the switches along an edge of the printed circuit board is not so easy to achieve g iven the current design of miniaturized switches which are fixed on the board by the flat transfer technique. Moreover, given the ever larger number of electronic functions integrated into a portable telephone, and the complexity of these operations when this involves in particular surfing the "Internet" network with a view in particular to accessing messaging functions, it is desirable to minimize the bulk of the switches on the printed circuit board. The document US-A-5, 180,050 describes and represents a rotary electric switch also having axial actuation of the type comprising a single actuation member which is mounted rotatably and axially slid ing ly along its axis of rotation, in a housing of the switch, in such a way as to rotate an upper coding wheel which cooperates with a first series of contact elements carried by the housing , and in such a way as to constitute the axial control member for the triggering of an elastically deformabie lower conductive element, from a stable rest position, so that it cooperates with a second series of fixed contact elements carried by the housing , and of the type in which an upper span of the single actuation member is guided in rotation and in axial sliding , in a complementary upper part of the housing . By virtue of such a design, it is possible to produce numerous electrical signals by virtue of the coding wheel which can be rotated in one or other direction so as to produce in succession separate series of electrical pulses. By acting axially on the single actuation member, it is possible to produce, regard less of the angular position of the sing le actuation member around its axis of rotation , an electrical enabling pulse by pressing on the single actuation member, that is to say more precisely by pushing the central part of the control button fixed to the upper free end of the single actuation member which projects axially out of the housing , the large diameter peripheral part of the control button serving for the rotational manipulation of the latter, that is to say for the rotational driving in the two d irections of the single actuation member and hence of the coding wheel. The invention aims to propose a novel design of an electric switch of this type which makes it possible to construct a switch of very reduced dimensions and in which the various components are of simple design, whilst easing the operations for mounting and assembling the switch . The invention also aims to allow better axial guidance of the sing le actuation member so as to avoid interference-jamming phenomena, especially when the user acts on the periphery of the control button so as to axially depress the latter with a view to producing an electrical enabling pulse. For this purpose, the invention proposes a switch of the type mentioned above, characterized in that the lower end span of the sing le actuation member runs axially downwards through the lower conductive element and is guided in rotation and in axial sliding in a complementary lower part of the housing . Accord ing to other characteristics of the invention : - the lower end span of the single actuation member is a cylindrical span which is received in a complementary hole formed in a lower wall of the housing ; - the coding wheel is axially secured to the single actuation member ; - the single actuation member comprises a collar for axial control of the triggering of the lower conductive element whose d iameter is g reater than the diameter of the lower end span of the single actuation member and wh ich delimits a shoulder oriented axialiy downwards which runs opposite a facing part of the upper face of the lower conductive element ; - the elastically deformabie lower cond uctive element constitutes the spring for returning the single actuation member, vertically upwards, into a position corresponding to the stable rest state of the lower conductive element ; - the control collar belongs to the coding wheel ; - the elastically deformabie lower conductive element returns the single actuation member, vertically upwards, into a rest position determined by the abutting of the upper face of the coding wheel against a facing part of the lower internal face of an upper wall of the housing ; - the housing comprises a hollow upper part and a hollow lower part which delimit between themselves an internal cavity in which are arranged the various components of the switch, and in that the upper part comprises a horizontal upper wall comprising a passage through which the upper free end of the sing le actuation member projects axially upwards so as to constitute a stem for operating the rotation and axial sliding of the single actuation member ; - the electrical contact elements of the said first series are mounted held vertically between the two upper and lower parts of the housing level with the horizontal sealing plane connecting the two parts. Other characteristics and advantages of the invention will become apparent on reading the detailed description which follows for the understanding of which reference will be made to the appended drawings in which : - Figure 1 is an exploded perspective view of the main components of an exemplary embodiment of an electric switch in accordance with the teachings of the invention ; - Figure 2 is a perspective view of the electric switch of Figure 1 which is illustrated in the assembled position of its components ; - Fig ure 3 is a view on a large scale, in axial section through a vertical plane along the line 3-3 of Figure 6, in which the sing le actuation member is illustrated in the top axial position of rest ; - Figure 4 is a view on a large scale along the line 4-4 of Figure 5 ; - Figure 5 is a plan view on a large scale of the electric switch of Figure 2 ; - Figure 6 is a side view on a large scale of the electric switch of Figure 2 ; and - Figure 7 is a sectional view along the line 7-7 of Figure 6. I n the description which follows, identical, similar or analogous components and elements will be designated by the same reference numerals. In order to aid the understanding of the description and the claims, the terms horizontal, vertical, upper, lower, etc. will be used , non-limitingly, with reference in particular to Figures 1 , 2, 3, 4 and 6 of the appended drawings. The electric switch 10 according to the invention consists in essence of a housing 13 made of an insulating plastic comprising an upper part 12 and a lower part 14 which are joined together along a horizontal sealing plane P. The upper part 12 of the housing 10 consists in essence of a horizontal upper wall 16 of substantially rectangular shape which comprises a cylind rical central hole 18 with vertical axis A, and of a side wall 20 delimited by an annular lower face 22 which , in cooperation with the corresponding upper annular face 24 of the lower part 14 of the housing 1 3, delimits the sealing plane P. Likewise, the lower part 14 consists in essence of a lower horizontal wall 26 in the form of a rectangular plate, thicker than the upper wall 16 , and of a side wall 28. The side walls 20 and 28 laterally delimit an internal cavity 30 of the housing 13 which is delimited vertically towards the bottom and towards the top respectively by the internal upper face 32 of the lower wall 26 and by the internal lower face 34 of the upper wall 16. The electric switch 1 0 also comprises a single actuation member 36 which takes the form of a globally cylind rical stepped member with vertical axis A which is mounted rotatably and axially slidingly in the housing 1 3 of the switch 10. The single actuation member 36 in the form of a stepped cylindrical rod is for example a moulded plastic piece whose upper free end 38, fir-tree-shaped in section , projects axially vertically upwards, through the cylindrical hole 1 8 , out of the housing 13 so as to allow the mounting of a control button, not represented in the figures, allowing the single actuation member 36 to be rotated, about the axis A, and slid axially, by downward vertical depression . The fir tree shape, together with a ring of notches, allows the mounting and fixing of a control button in a sing le operation, in an undismantleable manner, without excessively raising the total height of the switch/button assembly, that is to say while keeping very reduced overall d imensions. The large diameter upper span 40 of the stepped rod 36 is axially slidingly and rotatably received in the upper hole 18. It runs vertically downwards inside the cavity 30 and it is extended by an intermediate span 42 of lesser diameter, then by a lower free end span 44 of smaller diameter which runs axially downwards through, in accordance with the teachings of the invention, a complementary cylindrical hole 46 formed in the lower wall 26 of the lower part 14 of the housing 13. Thus, the single actuation member 36 is guided rotationally and axially slidingly in zones or spans 40-18 and 44-46 which are maximally axially spaced given the overall height of the housing 13 which here is, by way of example, equal to 2.75 mm. To have a large guidance length of the lower span 44, as is represented in the figures and in particular in Fig ure 3, the lower wall 26 of the lower part 14 of the housing 13 is extended axially downwards by a central guidance ferrule 48 which projects beyond the external lower face 50 of the lower wall 26, this ferrule being for example received in a complementary hole of a printed circuit board , not represented , on which the electric switch 10 is mounted. According to a known overall arrangement, the single actuation member 36 carries and drives a coding wheel 52 which takes the form of a horizontal disc made of insulating plastic 54 delimited vertically towards the top by an annular upper face 56 and whose crenellated lower face receives and rotationally drives a conductive element 60 in the form of a star here comprising , by way of example, eight branches 62. As may be seen in the details, in particular in Figures 3 and 7, the central part of the disc 54 is complementary with the spans 40 and 42 of the stepped single actuation member 36 and complementary shapes are provided for the slippage-free rotational driving of the coding wheel 52 by the single actuation member 36 (see Figure 7) . The tabs or branches 62 are designed to cooperate or otherwise, as a function of the angular position of the single actuation member 36 and hence of the coding wheel 52 with respect to the housing 13, with fixed electrical contact elements belonging to a first series 70 of contact elements. As may be seen in particular in Figure 1 , this first series of contact elements 70 comprises a common central contact 72 with two parallel horizontal branches transversely spaced , each of which terminates in a free contact end 74 of inwardly curved shape with its convexity turned vertically upwards so as to cooperate permanently with the central annulus 61 which joins together the branches 62 of the star-shaped conductive element 60 of the coding wheel 52. The common fixed central contact 72 comprises a common connecting tab 76 which projects laterally out of the housing , the plane horizontal part 78 linking the tab 76 and the branches 74 being received clamped vertically at the level of the sealing plane P and in a complementary shape formed for example in the annular face 24, so as to immobilize the common contact 72 in the position mounted in the cavity 30. The first series of electrical contact elements 70 also comprises two separate contact elements 80 and 82 for constituting a rotary coding having two pathways according to whether a branch 62, depending on the angular position of the single actuation member 36, establishes electrical contact between a branch 74 and one or the other of the elements 80 or 82. In the same way as for the common central contact 72, each contact element 80, 82 comprises an inwardly curved free end 84, 86 intended to cooperate with a branch 62, and each contact element comprises a connecting tab 88, 90 and a horizontal linking part 92, 94. The various components which make it possible, by virtue of axial actuation of the single actuation member 36, to produce an enabling pulse will now be described . These components comprise in particular a conductive dome 100 and a second series 102 of fixed electrical contact elements carried by the lower part 14 of the housing 13. These components constitute, in a known overall manner, a simple monostable electric switch . I n a known manner, the electrical contact elements of the series 102 take the form of metallic inserts embedded in the moulded plastic of the lower part 14, which, to ease the understanding of their construction , are also represented in an exploded manner in Figure 1 . These electrical contact elements comprise a common central contact 104 with an annular central part 106 and a connecting tab 108 which projects laterally out of the lower part 14 of the housing 13. The electrical contact elements of the series 102 also comprise a common annular peripheral contact 1 10 which comprises two connecting tabs 1 12. In a known manner, and as may be seen in particular in Figure 3, the annular parts 106 and 1 14 of the two electrical contact elements 104 and 1 10 are flush in the bottom 32 of the lower part 14 of the housing so as to be able to cooperate with the elastically deformabie conductive dome 100 whose peripheral part 1 16 is always in contact with the annulus 1 14 and whose central part 1 18, when the dome 100 is in its stable rest position illustrated in the figures, is situated vertically above the annulus 106. Downward vertical depression, counter to its own elasticity, of the dome 100 causes its central part 1 18 to come into contact with the annulus 106 so as to establish electrical contact between the two electrical contact elements 1 04 and 1 10. To allow the passage of the lower free end span 44 for guid ing the single actuation member 36, the dome 100 comprises a central hole 120 through which the span 44 is received with radial play. I n order to constitute an axial control member for the triggering of the dome 100 , the single actuation member 36 acts on the latter's central part 1 1 8 so as to depress it vertically downwards. For this purpose, and according to the exemplary embodiment of the invention illustrated in the figures, the single actuation member 36 acts on the central part 1 18 of the dome 100 by way of an annular collar 122 belonging to the plastic disc 54 of the coding wheel 52. This collar 122 defines an annular shoulder 124 which is oriented axial ly downwards and which cooperates with the opposing upper face of the central part 1 18 of the dome 1 00. The dimensions of the various components are such that, as may be seen in particular in Figure 3 and in the stable rest position of the dome 100, that this part functions as a spring for elastically returning , vertically upwards, the single actuation member 36 by acting on the collar 122 of the cod ing wheel 52 which repels vertically upwards the single actuation member 36 to which it is tied in terms of rotation and axial translation . The topward position of rest of the coding wheel 52, and hence of the single actuation member 36, being determined by the abutting of the upper face 56 of the disc 54 of the cod ing wheel 52 against the opposing lower face 126 of an annular relief portion 128 formed centrally in the internal lower face 34 of the upper part 12 of the housing 1 3. Thus, starting from the rest position illustrated in Figure 3, and regardless of the ang ular position of the single actuation member 36, and hence of the coding wheel 52, at this instant, it is possible to deform the dome 1 00 by acting on the single actuation member 36, then functioning as a push button , so as to cause the downwards axial translation of the coding wheel 52, and hence of the collar 122, which acts via its shoulder 124 on the dome 100. During the axial enabling action , the coding wheel 52 displaces vertically with the single actuation member 36 and it elastically deforms the branches of the electrical contacts 72, 80 and 82 which bend in the manner of built-in beams. During this depression , a self-wiping effect occurs between the convex inwardly curved free ends 74, 84, 86 of the branches of the contacts of the first series 70 and the corresponding contacting parts of the lower face of the star 60, 61 , 62. By way of a variant (not represented) , it is possible to construct the control shoulder integral with the single actuation member 36. To assemble the two parts 12 and 14 of the housing 13, that is to say to close up the housing with all its components in the cavity 30, provision may for example be made for means of linking by elastic interlocking , or clipping , which here are represented by way of example in the form of four lugs 130 which run vertically upwards from the four opposite corners of the annular upper face 24 of the lower part 14 so as each to be received through a complementary hole 132 formed in the upper part 12 of the housing 13 , each lug 130 comprising a vertical- retention upper beading 134. By way of a variant, the headings 134 can be made after assembly by hot crimping . The design according to the invention makes it possible to obtain a switch of very reduced dimensions insofar as, in addition to its thickness or heig ht of 2.75 mm, its width and its length are respectively equal to 7 and 8 mm.

Claims: CLAI MS 1 . Rotary electric switch (10) also having axial actuation of the type comprising a single actuation member (36) which is mounted rotatably and axially slidingly along its axis of rotation (A), in a housing (1 3) of the switch , in such a way as to rotate an upper coding wheel (52) which cooperates with a first series (70, 72, 80, 82) of contact elements carried by the housing (13), and in such a way as to constitute the axial control member for the triggering of an elastically deformabie lower conductive element ( 100), from a stable rest position , so that it cooperates with a second series (1 02, 104, 1 10) of fixed contact elements carried by the housing (13), and of the type in which an upper span (40) of the sing le actuation member (36) is guided in rotation and in axial sliding , in a complementary upper part (12, 18) of the housing ( 13) , characterized in that the lower end span (44) of the single actuation member (36) runs axially downwards through the lower conductive element (100, 120) and is guided in rotation and in axial sliding in a complementary lower part ( 14, 46) of the housing ( 1 3) . 2. Electric switch (10) according to the preceding claim, characterized in that the lower end span (44) of the single actuation member (36) is a cylindrical span which is received in a complementary hole (46) formed in a lower wall (14, 26) of the housing (13). 3. Electric switch (10) according to any of the preceding claims, characterized in that the coding wheel (52) is axially secured to the single actuation member (36) . 4. Electric switch (10) accord ing to any one of the preced ing claims , characterized in that the single actuation member (36) comprises a collar (122) for axial control of the triggering of the lower conductive element whose diameter is greater than the diameter of the lower end span (44) of the single actuation member (36) and which delimits a shoulder ( 124) oriented axially downwards which runs opposite a facing part (1 18) of the upper face of the lower conductive element (100). 5. Electric switch (10) according to the preceding claim, characterized in that the elastically deformabie lower conductive element (1 00) constitutes the spring for returning the single actuation member (36), vertically upwards, into a position corresponding to the stable rest state of the lower conductive element. 6. Electric switch (10) according to one of Claims 4 or 5, taken in combination with Claim 3, characterized in that the control collar (122) belongs to the coding wheel (52). 7. Electric switch (10) according to the preceding claim, characterized in that the elastically deformabie lower conductive element (1 00) returns the single actuation member (36), vertically upwards, into a rest position determined by the abutting of the upper face (56) of the coding wheel (52, 54) against a facing part (126, 128) of the lower internal face (34) of an upper wall (16) of the housing (13). 8. Electric switch (10) according to any one of the preceding claims, characterized in that the housing ( 13) comprises a hollow upper part (12) and a hollow lower part (14) which delimit between themselves an internal cavity (30) in which are arranged the various components (36, 52, 70, 1 02) of the switch , and in that the upper part (12) comprises a horizontal upper wall (16) comprising a passage (18) through which the upper free end (38) of the single actuation member (36) projects axially upwards so as to constitute a stem for operating the rotation and axial sliding of the single actuation member (36). 9. Electric switch (10) according to the preceding claim, characterized in that the electrical contact elements of the said first series (70) are mounted held vertically between the two upper (12) and lower (14) parts of the housing (13) level with the horizontal sealing plane (P) connecting the two parts.

Inventors: JANNIERE ALAIN, JURET BERNARD, JANNIERE, ALAIN, JURET, BERNARD
Applicants: ITT MFG ENTERPRISES INC, JANNIERE ALAIN, JURET BERNARD, ITT MANUFACTURING ENTERPRISES INC., JANNIERE, ALAIN, JURET, BERNARD
Application year: 2000
Main classification: H01H25
IPC codes: H01H25