FR2769125A1 - ECONOMICAL ROTARY SWITCH FOR CONTROL PANEL - Google Patents

Abstract

The device comprises two molded parts, one of which is fixed and the other can rotate around an axis and perform a reciprocating movement along this axis. The cooperation of four toothings arranged in a ring around the axis transforms an axial back and forth into a rotational movement of a predefined angle. A first series of teeth 33 of the movable part cooperates with a first series of teeth 30 of the fixed part in order to rotate the movable part, on the outward journey, by a fraction of said predefined angle. On return, a second series of teeth 36 of the moving part cooperates with a second series of teeth 34 of the fixed part to complete the rotation. The device can be used in particular as a switch or inverter in a heating or air conditioning control panel in the passenger compartment of a vehicle.

Description

* 1 Economic rotary switch for control panel The invention

  relates to a switching device, in particular for a vehicle heating / ventilation or air conditioning control panel, comprising a stator and a rotor

  suitable for occupying at least two positions relative to the stator

  angular working positions, said working positions being deduced from each other by a rotation of a predefined angle about an axis, the rotor being provided with a contact member which selectively comes into electrical contact, according to the angular position of the rotor, with conductive pads extending substantially in a plane perpendicular to the axis

  to define an electric circuit of variable configuration.

  Such a device can be used for example for controlling

  der the opening and closing of the electric circuit, or the stopping and running in one direction and the other of an electric motor. The number of circuit configurations is 2 in the first case and 3 in the

  second case. It can also have other values.

  The object of the invention is to provide such a device in a simple and economical manner, by giving it simplicity

  of use, compactness, precision and reliability.

  The invention relates in particular to a device of the kind defined in

  introduction, and provides that the rotor and the stator include

  first and second molded parts are respectively provided each with a first toothing and a second toothing arranged in a crown around the axis, the first

  molded part also being movable in parallel translation-

  ment to the axis, relative to the second molded part, between first and second axial positions, the first teeth cooperating with each other to transform a first axial movement of the first molded part from its first axial position to its second axial position in an angular movement of a fraction of said predefined angle from one of said working positions, and the second teeth cooperating with each other to transform a second axial movement of the first molded part from its second position

  axial to its first axial position in an angular movement

  laire of the complementary fraction of said predefined angle to the next working position, the first molded part being biased towards its first axial position by

elastic return means.

  The translational movement of the rotor is transformed into a rotational movement between two working positions by the cooperation of teeth belonging to two molded parts.

  only, which allows simple and economical manufacturing

  than. The absence of an intermediate part ensures good precision of the rotor positions and good reliability of the device. Finally, the user just has to press a push button located for example on a control panel to switch from one working position to another, then release it to allow the stator to make its second axial movement under the action of the means of recall

elastic.

  Optional features of the invention, complementary

  or alternative, are set out below: - The teeth of a first of the two pairs formed respectively by the first teeth and by the second teeth project axially towards one another so as to come into mutual contact during some movement

corresponding axial.

  - The teeth of said first pair are the first teeth. - The second molded part has the general shape of a cup, the bottom of which internally has teeth of

said first pair.

  - Each of the teeth of the second pair consists of a multiplicity of teeth projecting radially outward for one toothing and inward for the other toothing, the teeth of each toothing being sufficiently

  spaced apart from each other in the circumferential direction

  tial to allow the passage of the teeth of the other toothing during the purely axial movement preceding the entry into

  mutual contact of the teeth of the first pair.

  - In each angular working position, each tooth of one of the teeth of the second pair is framed and immobilized in the circumferential direction by two

teeth next to the other teeth.

  - The teeth of a toothing of the second pair project radially inwards from the side wall of

the cup.

  - The conductive areas are defined by metal blades fixed to a peripheral edge of the cup and delimiting with it a volume in which is trapped

the rotor.

  - The contact member is integral in translation with the first molded part so as not to be in contact with the

  conductive pads only in said first axial position.

  - Said predefined angle is contained an integer number of times

in a ride.

  The characteristics and advantages of the invention will be

  described in more detail in the description below, in

  referring to the appended drawings, in which: - Figures 1 and 2 are exploded perspective views of a switching device according to the invention; - Figure 3 is an axial sectional view of the device; - Figure 4 is a diagram illustrating the mutual cooperation of the teeth of the different teeth; and

  - Figures 5 and 6 are diagrams illustrating the cooperation

  mutual agreement between the contact member and the conductive areas

trices.

  In the description below, the convenience will be adopted

  convention that the device is oriented in space as shown in Figure 3, that is to say the axis of the rotor being vertical and the first axial movement being directed from bottom to top. In reality, the device can

  operate in any orientation. In particular

  link, when it is part of a motor vehicle heating or air conditioning control panel, the axis

  is generally roughly horizontal and the first movement

  axial stator is oriented towards the front of the vehicle.

  The illustrated device comprises a stator 1 fixed by means not shown on the control panel not shown of an air conditioning installation of the passenger compartment of a motor vehicle, and a rotor 2 movable relative to the stator 1 rotating around d 'an axis A and in translation along this same axis. The stator 1 comprises a part 3 of injection-molded plastic material, having the general shape of a cup having a disk-shaped bottom 4 and a generally cylindrical side wall 5 of revolution, extending downwards from the periphery of the bottom 4. A tubular appendage 6 extends upwards from the central part of the bottom 4. A blind bore 7, cylindrical of revolution around the axis A, passes through the bottom 4 and the appendix 6 and is closed at its upper end by a second bottom 8. The side wall 5 is connected downwards to an annular flange 9 extending radially outwards, and a flange 10 turned axially downwards

  extends from the periphery of the flange 9.

  The stator also comprises three metal blades 11, 12 and 13, having as a whole, as shown in FIGS. 5 and 6, a circular contour whose diameter corresponds to the inside diameter of the flange 10. These three blades are applied to the underside of the flange 9 and fixed by lugs 14 formed on this face and folded down like rivet heads on the underside of the blades. Each of the three blades thus extends over a fraction

  of the circular surface delimited by the rim 10.

  The rotor 2 comprises a piece 15 of injection molded plastic. The part 15 also forms a cup comprising a bottom 16 oriented radially and a substantially cylindrical side wall 17 of revolution extending upwards from the periphery of the bottom 16. The

  cup 16, 17 is housed in volume 18 delimited radially-

  ment by the side wall 5 of the part 3, upwards by the bottom 4 of the latter and downwards by the blades 11-13. The part 15 also comprises a rod 19 projecting along the axis A, downwards from the bottom 16, and passing through a hole 20 in the blade 11. A tubular projection 21, open at its upper end, extends towards the top, along the axis

  A, from the bottom 16, and adjusts in the bore 7.

  The rotor further comprises a metal disc 22 pierced in its center to thread onto the rod 19 and fixed to the underside of the bottom 16 by means of lugs 23 projecting from the latter, passing through notches 24 formed

  at the periphery of the disc 22 and folded down on the underside

  laughter of it. Three short slots 26 formed in the disc 22, at mutual distances of 120, extending substantially circumferentially a short distance from the peripheral edge of the disc, delimit with this edge respective bands 27 which are deformed downwards out of the plane of the disc to form contact pads 27 capable of coming into contact with the blades 11-13. A helical spring 28, housed in the bore 7 and inside the tube 21, is supported

  upwards on the bottom 8 and downwards, via

  diary of a ball 29, on the bottom 16.

  Each of the parts 3 and 15 has two teeth arranged in a crown around the axis A. A first toothing of the part 3 comprises twelve teeth 30 projecting from the bottom 4, having working surfaces 31 turned axially downwards and inclined to a horizontal plane. These faces 31 are arranged vis-à-vis the upper faces 32 similarly inclined with four teeth 33 formed on the upper face of the bottom 16 of the part 15 and located at mutual angular distances of 90 o. The second toothing of the part 3 comprises three teeth 34 projecting radially inwards from the side wall 5 and located at mutual angular distances from. Each tooth 34 has a working surface 35 turned axially upward and inclined relative to a horizontal plane, in the opposite direction to the inclination of the surfaces 31 and 32. The second teeth of the part 15 is composed of twelve teeth 36 regularly distributed around the axis A, projecting radially outward from the wall 17, and each having a surface of

  work 37 inclined in the same way as surfaces 35.

  For each of the three teeth 34, an opening 38, formed in the bottom 4 and in the side wall 5, allows, during the demolding of the part 3, the extraction of a mold element necessary for the production of the tooth, which allows

  make teeth 34 and 30 in a single molded part.

  Figure 3 shows the rotor in a first axial position or low position, in which it is held by the spring 28 so that the contact pads 27

  come into contact with the metal blades 11-13.

  FIG. 4 represents the partial development in a plane of the radial projection on a cylindrical surface of the profiles of the four teeth described above. Unlike the twelve teeth 30, which follow one another without interruption like saw teeth, the twelve teeth 36 are spaced from each other, by a distance slightly greater than the circumferential length of the teeth 34. In the first axial position, as we seen in Figure 4, each of the teeth 34 is interposed between two consecutive teeth 36, which corresponds to a well defined angular position of the stator. At the same time, the projecting edge 40 delimiting upward the working surface 32 of each tooth 33 is at a slightly lower level, for example 0.3 mm, than the projecting edges 41 delimiting the surfaces downwards.

  working 31 of the teeth 30, and the edge 40 is axial-

  ment opposite a point 42 of the surface 31 of one of the teeth 30 near the edge 41 of the same tooth. The rod 19 cooperates, directly or indirectly, with a push button mounted on the control panel, allowing the rod 19 to be pushed in to move the rotor upwards, the tube 21 sliding in the bore 7. The movement of the rotor is then purely axial, for example over a length of 0.6 mm, until the edge 40 of each tooth 33 comes into contact with the surface 31 of the tooth 30 opposite point 42. Then , the surface 32 of the tooth 40 slides on the surface 31 of the tooth 30, producing a rotational movement concomitant with the axial movement, until the edge 40 comes to coincide with the re-entrant edge 43 which limits upwards the surface 31, as shown in broken lines in FIG. 4. The total axial stroke thus produced is for example 2 mm. The teeth 34 and 36 have respective inclined surfaces 44 and 45 which pass opposite and at a distance from each other during the above helical movement, the angular amplitude of which corresponds to the angular distance between the point 42 and the edge 43 of each tooth 30, a little less than a twelfth of a turn. In the position thus reached, the teeth 36 are at a higher level than the teeth 34, and the tooth 36-1 which was initially at the right of a tooth 34, that is to say upstream of that here relative to the direction of rotation of the rotor, is now located so that its working surface 37 is axially opposite the working surface 35

  tooth 34. When the user releases the button-

  spring 28 pushes the rotor down, in a purely axial movement until the surfaces 35 and 37 come into mutual contact. Then, the axial movement is accompanied by a rotational movement in the same direction as the previous one, due to the cooperation of these same surfaces, until the tooth 34 can penetrate the interval between the tooth 36 -1 and the next tooth of the same teeth. The rotor has then turned a twelfth of a turn, and maintains this angular position until it returns to its

first axial position.

  The blades 11, 12 and 13 are obtained by eliminating the peripheral region of a monobloc disc 50 shown in Figures 1 and 2, provided with electrical connection tabs 51, 52 and 53 which remain attached respectively to the blades 11, 12 and 13 and pass through notches 39 formed in the rim 10. The blade 11 comprises an annular region 54 surrounding the central hole 20, and two opposite angular sectors 55 and 56, both symmetrical with respect to an axis A1 situated in the plane of the blades and intersecting the axis A. The blades 12 and 13, symmetrical to one another with respect to the axis A1, are respectively disposed in the two remaining angular sectors and are separated from the region 54 and from the sectors 55 and 56 by intervals formed by two internal cutouts 57 formed in the disc 50. The cutouts 57 also form respective notches 58 in the blades 12 and 13, facing the annular region 54, each of the blades 12 and 13 thus entering, on the part and

  on the other side of the notch 58, directed radially inwards

  laughing, a horn 59 close to sector 55 and a horn 60

close to sector 56.

  It follows from the above description that the rotor can

  occupy with respect to the stator twelve stable working positions, deducing from each other by rotations of a twelfth of a turn, that is to say 30 o, and in which the studs 27 come into contact with the blades 11 -13. Each pad 27 can therefore occupy twelve positions relative to the blades, these twelve positions being the same for the three pads which are arranged in a pitch of 120, multiple of. As can be seen in FIG. 5, where the three contact points used for a particular working position of the rotor are designated by the reference 61 and the other nine by the reference 62, the twelve contact points of the pads 27 are symmetrical two two to the A1 axis. Among the six contact points located on each side of this axis, two are on the sector 55, one on the horn 59 of the blade 12 or 13 placed on this side, one at the notch

  58, one on horn 60 and the last on sector 56.

  The three contact points 61 in FIG. 5 are those of the sector 55 contact points furthest from the axis A1

  below this, that of sector 56 also below

  below the axis A1, and that of the horn 59 above the axis. For a working position close to the previous one, the contact points used 61 are those shown on the

  Figure 6, respectively closest to the axis A1, au-

  below it, on sector 55, on horn 60 au-

  below the axis and between the horns 59 and 60 above the axis. In the position of FIG. 5, the contact disc 22 electrically connects the blade 12, shown above the axis Ai, to the blade 11 and the blade 13 is switched off. In the position of FIG. 6, it is the blade 12 which is off and the blade 13 connected to the blade 11. By continuing to rotate in the same direction, we then reach a position where the contact points are symmetrical with those of FIG. 6 relative to the axis A1, which corresponds to the same configuration of the circuit as the position of FIG. 5, then a position where the contact points are symmetrical to those of FIG. 5, corresponding to the same configuration as the position of Figure 6. We then find the arrangement of Figure 5, each stud having rotated, and so on. Thus, for the successive working positions, the disc 22 alternately places the blade 12 and the blade 13 in connection with the blade 11. For all the intermediate angular positions of the rotor, the three studs 27 are distant from the blades 11-13 due axial movement of the rotor, which avoids any electrical interference. The device can be used as a simple switch, in particular for putting a refrigerant compressor on and off, one of the tabs 52 and 53 not being connected to the electrical circuit, or as an inverter, for example for feed in one direction and in the other the drive motor of an air inlet flap. It also allows, by adapting the number and shape of the conductive pads, to achieve a higher number of

  electrical circuit configurations.

  Conversely, the two configurations sought in the example described could be obtained with less than twelve working positions of the rotor. This number has been chosen here so as to reconcile a sufficiently large inclination of the working surfaces of the teeth (of the order of 45 °) to ensure that the rotor is driven in rotation, a reduced axial stroke and a diameter of the teeth sufficient to allow

their manufacture.

he

Claims (10)

Claims   1. Switching device, in particular for vehicle heating / ventilation or air conditioning control panel, comprising a stator (1) and a rotor (2) suitable for occupying at least two angular working positions relative to the stator, said positions work deducting from each other by a rotation of a predefined angle about an axis (A), the rotor being provided with a contact member (22) which selectively comes into electrical contact, according to the angular position of the rotor, with conductive pads (11-13) extending substantially in a   plane perpendicular to the axis to define an electric circuit   that of variable configuration, characterized in that the rotor and the stator respectively comprise first and second molded parts (3, 15) each provided with a first toothing and a second toothing arranged in a crown around the axis, the first molded part also being movable in translation parallel to the axis, relative to the second molded part, between first and second axial positions, the first teeth (30, 33) cooperating with each other to transform a first axial movement of the first molded part from its first axial position to its second axial position in an angular movement of a fraction of said predefined angle from one of said working positions, and the second teeth (34, 36) cooperating with each other to transform a second axial movement of the first molded part from its second position   axial to its first axial position in an angular movement   laire of the complementary fraction of said predefined angle to the next working position, the first molded part being biased towards its first axial position by   elastic return means (28).   2. Device according to claim 1, characterized in that the teeth (30, 33) of a first of the two pairs formed respectively by the first teeth and by the second teeth project axially towards one another so as to come into mutual contact during the movement corresponding axial.   3. Device according to claim 2, characterized in that the teeth of said first pair are the first teeth. 4. Device according to claim 3, characterized in that the second molded part has the general shape of a cup whose bottom (4) internally carries a toothing (30) of said first pair.   5. Device according to one of claims 2 to 4,   characterized in that each of the teeth of the second pair consists of a multiplicity of teeth projecting radially outward for one toothing (36) and inward for the other toothing (34), the teeth of each toothing being sufficiently spaced from each other in the circumferential direction to allow the passage of the teeth of the other toothing during the purely axial movement preceding the coming into mutual contact of the teeth of the first pair.   6. Device according to claim 5, characterized in that, in each angular working position, each tooth (34) of one of the teeth of the second pair is framed and immobilized in the circumferential direction by two   neighboring teeth (36) of the other toothing.   7. Device according to one of claims 5 and 6,   Attached to claim 4, characterized in that the teeth (34) of a toothing of the second pair protrude radially inwards from the side wall (5) of the cup.   8. Device according to one of claims 4 and 7,   characterized in that the conductive areas are defined   by metal blades (11-13) fixed to a peripheral edge   that (9, 10) of the cup and delimiting therewith a   volume (18) in which the rotor is trapped.   9. Device according to one of the preceding claims,   characterized in that the contact member (22) is integral in translation with the first molded part (15) so as to be in contact with the conductive pads only in said first axial position.   10. Device according to one of the preceding claims,   characterized in that said predefined angle is contained a whole number of times in a round.