FR2638273A1 - Assembly of flat linear actuating modules - Google Patents

Abstract

The present invention relates to an assembly of flat linear actuating modules, in which each module comprises a flat movable coil 20, 22, 24 mounted on tracks 31, 32. On each side of this coil and approximately parallel to it is a flat means for applying a magnetic field perpendicularly to the plane of the coil, this field being in one direction in one half of the area occupied by the coil at rest and in the opposite direction in the second half. One magnetic field application means only is present between two coils, and closure means surround the terminal magnetic field application means.

Description

ENOUGH! BLOCKING OF MODULES ACTUATED;! FLAT LINEAR RS
The present invention relates to the field of electronic keyboard music devices and the production of an assembly of flat modular actuators.

In electronic music devices, we have made a lot of progress as far as the electronic part is concerned and, from a musical point of view, a given device can fulfill very many functions thanks to the various programs that we can introduce into a processor. control. However, the mechanical part of electronic keyboard devices is still quite primitive, lacking flexibility in many respects
- on the one hand, it is generally not possible to replace at one chosen location on the keyboard one type of key with another (for example a piano key with a joy stick (control stick), a white key with a black button, etc.);
- on the other hand, all the keys constituting the keyboard are fixed in advance and it is not possible for the user to increase the number of keys without buying a new complete keyboard.

 Thus, a first object of the present invention is to provide a keyboard of an electronic music device having more flexibility of manufacture and use than the keyboards of the prior art.

 For this, the present invention provides a modular keyboard.

 Another object of the present invention is to provide such an apparatus in which the keys are retroactive, that is to say oppose to the actions of the user a reaction of a nature chosen according to the type of function which one wishes to confer. - go to the button.

 To obtain this retroactivity, as is known, it is necessary to associate 9 each key module with a driving element. One of the prejudices which the invention had to overcome resides in the fact that the realization of a motor element of suitable power and sufficiently flat to fit in the space allocated for example to a piano key, seemed an insurmountable obstacle technically and / or economically. Indeed, if we consider an octave of classical piano (12 keys), it occupies a width of 165 millimeters, that is to say that the mechanics associated with each key has a width which must not exceed 13.75 millimeters.

To make a perfect modular system, it is desirable that each motor element does not exceed this width. Otherwise, we would have to shift the motor elements relative to each other, which would mean that the system would no longer be perfectly modular.

 Another object of the present invention has therefore been to provide a particular flat linear motor which can be assembled in modular fashion with other motors. This motor, or modular actuator according to the present invention can of course find other applications than those of a musical instrument keyboard, and could for example be used in the field of robotics.

 To achieve these and other objects, the present invention provides a modular retroactive keyboard provided with keys making it possible to return to the user a characteristic sensation of said key, in which each key is an element of a flat, self-contained parallelepiped module comprising a motor, a position sensor and electrical connection cores, each module includes means for fixing it to the adjacent module, the keys are connected to a central processing unit to give them the desired response by action on the motor and to process the sensor signals.

 According to an embodiment of the invention, each module comprises a plate or mobile arm identical for all the keys, this plate comprising means for interchangeably fixing thereon facings having the desired appearance, shape and dimension of a considered, original or classic instrument.

 According to another aspect, the present invention provides for an assembly of flat linear actuator modules. Each module includes: a flat moving coil mounted on slides allowing it to slide in its plane in a given direction, means for supplying current to the coil, of each category of this coil and substantially parallel thereto a flat means for applying a magnetic field in a direction orthogonal to the plane of the coil, this field being in a first direction in a first half of the surface occupied by the coil at rest and in the opposite direction in the second half, and spacing means to maintain a constant distance between the magnetic field application means. In this assembly, only one magnetic field application means is present between two coils, and closing means surround the means. application of extreme magnetic field.

 According to one embodiment of the present invention, the magnetic field application means are permanent magnets in the form of plates oriented in opposite directions in each half surface.

 According to an embodiment of the present invention, the magnetic field application means are flat coils oriented in opposite directions in each half surface.

 According to one embodiment of the present invention, this assembly comprises identical support frames provided with spacing means with respect to the neighboring chasies, each base comprising fixing means for carrying: a means for applying a magnetic field, guide rods of an adjacent flat mobile spool, a position detector of said coil.

These objects, characteristics and advantages, as well as others of the present invention, will be explained in more detail in the following description of exemplary embodiments made in connection with the appended figures, which:
Figure 1 shows a keyboard according to the present invention consisting of modular keys;
FIG. 2 illustrates the fact that various functions can be associated with each key
FIG. 3 is an extremely diagrammatic representation of a modular actuator according to the present invention;
FIGS. 4A and 4B represent top views of magnets included in an actuator module according to the present invention
FIG. 5 represents a simplified schematic perspective view of two modules of an actuator according to the present invention; ;
FIG. 6 represents a front view of an actuator module according to the present invention; and
FIG. 7 schematically illustrates a matrix assembly of actuator modules according to the present invention.

Thus, Figure 1 schematically illustrates the type of embodiment of a keyboard according to the present invention. This keyboard comprises individual modules 1, each of which comprises an actuating arm or plate 2. Inside the module are included:
- a key position detector,
- an elenent motor or actuator making it possible, depending on the action detected on the key, to provide a resistive and possibly return force determined by a central processor receiving from each key the position indication and providing a control for the motor. In addition, 9 each module is associated with an electronic card comprising means for preprocessing the detector signals and means for amplifying signals; returned by the central processor.

 According to a characteristic of the invention, these modules can be connected together in a simple manner, for example by snap-fastening or by fixing by rods and clamping.

 According to one aspect of the invention, as shown in FIG. 2, in the case where the keyboard is intended to form a keyboard for a musical instrument, the trays or arms 2 can be provided with facings corresponding to the appearance of the keys musical instrumental classics, for example a black key 4, a white key 6 or a joy stick 8.

 Thus, the modular keyboard according to the present invention has the double advantage of being able to understand any number of keys but in addition that each key can be associated with a different function provided that the associated program is properly modified in the process! central to have the reactions corresponding to this type of key.

 FIG. 3 shows schematically and simplified a type of motor suitable for producing actuator modules which can be used for example in a keyboard such as that illustrated in FIG. 1. This motor comprises means for creating fixed magnetic fields of shape flat, hereinafter called polarization elements, between which are arranged coils movable in translation in their plane. The voice coils receive a current determined by a central processor.

 Each polarization element is divided into two halves along a vertical plane, as shown by flowers 4A and 4B, so as to apply fields in opposite directions in each of these two halves.

 Figure 4A represents the case where each polarization element comprises in its left part a magnet plate 10 whose north face is visible and in its right part a magnet plate 11 whose south face is visible.

 As shown in Figure 43? for reasons of comfort and cost of the lovers, each plate could be divided into several elementary plates, for example lO-l and 1n-2 for the left part and 11-1 and 11-2 for the dodo part.

 More particularly, FIG. 3 represents three polarization elements 14, 16 and 18 in the form of plates and three flat coils 20, 22 and 24. In addition, to the left of the polarization element 14 which is at one end of a set of modules is disposed a closing plate of the magnetic field 26, for example a soft iron plate. Thus, for example, to constitute an assembly of two modules according to the present invention, one will successively assemble a first closure plate 26, a polarization element 14 then successive assemblies corresponding to each module including a movable flat coil 20 and an element of fixed polarization 16 then a second moving coil 22 associated with its polarization element 18. To make a set of two modules only, instead of placing a new coil 24 behind the polarization element 18 as shown, we will place behind this element 18 a closing plate for the field lines similar to the plate 25.

 The assembly of FIG. 3 shows that, except for the ends of the assembly, to add a module to an existing assembly, it suffices to add an assembly comprising a polarization element and a coil.

 Thus, as will be seen below, the present invention provides elementary modules comprising, on a fixed chassis, provided with means of connection with the adjacent chassis, a support for a biasing element and a moving coil.

 FIG. 5 represents a perspective view a little more detailed than that of FIG. 3 but still very schematic of a set of two polarization elements 15 and the and of two moving coils 22 and 24. Each moving coil is linked to runners 30 and 31 capable of sliding on guide rods 32 and 33, these rods being, as will be seen below, secured to a chassis carrying a polartsation element adjacent to the spool. In addition, each spool is attached to a set of translational movement into rotational movement comprising a first arm 34 integral with the coil and moving from front to back and from back to front in the direction of the current passing through the coil, and a second arm 35 articulated on an axis 36 also integral with the fixed frame of the polarization element associated with the coil considered. The connection between the articulated arm 35 and the reciprocating arm 34 is made by a conventional connection system schematically designated by a part in an arc 37. The arm 35 is linked to a third arm 37 which therefore moves in rotation relative to the axis 36. This third arm 37 corresponds to the aforementioned plate or actuating arm of the module considered. The dimensions of the various elements of the system for transforming translational movement into rotational movement, in relation to the value of possible displacement of the coil along the guide rods, will for example be chosen so that a possibility of travel is obtained. in rotation by 10 relative to a rest position.

It is on the arm or plate 37 that it will be possible to snap on or fix in another way selected facings.

 Of course, other means for transforming the translational movement into the rotational movement could be used and, for other applications, we could also seek to use the translational movement of the voice coil directly.

 FIG. 6 represents a front view of a schematic embodiment of a coil and of a magnetizing element mounted on a chassis to form an elementary module.

 The coil is designated by the reference 40 and its access terminals by the references 41 and 42.

 The polarization element comprises a plate 43 whose north face is visible and a plate 44 whose south face is visible so as to create opposite fields in the two vertical halves of the coil.

 As in the case of FIG. 5, a system for transforming the translational movement of the coil into a rotational movement has been shown, designated by the same references 34 to 38.

 The chassis 50 has a substantially flat rear face and comprises means for housing and blocking, for example by force, the magnetization plates 43 and 44. The ch ssis comprises means 51, 52 and 53, 54 for fixing the rods of guide 32 and 33 on which the moving coil 40 slides via the slides 30 and 31.

 Also shown at the upper part of the chassis, a resistive strip 60 whose ends are secured to access terminals 61 and 62. On this resistive strip can slide a short-circuit wiper 64 secured to the slide 31 so that the resistance between terminals 61 and 62 is representative of the position of the voice coil.

 On the other hand, projecting stops are provided to ensure a determined spacing with respect to the rear face of the adjacent chassis. There are shown four lateral stops 71 to 74 and a central stop 75. Preferably, the substantially planar rear face of the frames 50 will include notches intended, in cooperation with the stops 71 75 to position one relative to the other two successive chassis. Several chassis naturally "stick" to each other under the effect of magnetic attraction. It will however be preferable to provide passages for fixing rods or bolts.

 As will be clear for the fall of the art, for the set of actuator modules as illustrated in FIGS. 3, 5 and 6 to function satisfactorily, the chanp created by a moving coil should not have no influence on the adjacent coil. This will be the case if we ensure that the maximum field created by a coil when current flows through it does not exceed approximately one tenth of the field created by the polarizing elements.

 Returning to FIG. 3, it will be emphasized that a polarization element is used for the two coils which surround it. This makes it possible to obtain a particularly compact flat motor.

 The constraints set out above (width of 13.75 mm per module for a piano keyboard) could easily have been satisfied in the context of an experimental arrangement according to the present invention by using conventional elements comprising flat coils with a thickness of of the order of 6 mm, these coils forming part of a rectangle of 60 mm x 12n mm, and the polarization elements being made up of rare earth magnet plates with a thickness of 6 mm, which leaves a gap on each side of each coil less than 1mm (1.75 / 2mm).

 Hitherto, a linear form of modular assembly of flat actuators has been shown. Other types of assemblies are also possible.

 Figure 7 schematically illustrates an example of matrix assearblage. This assembly consists of Ait flat magnets (seen at the end) arranged in 4 rows (il1 ... 4) and 4 columns (j = l. .4). All the magnets in one column have the same direction of magnetization (symbolized by an arrow) and the magnets in two adjacent columns have opposite directions of magnetization. Coils B are arranged so as to undergo previously the field of polarization elements grouping magnets of adjacent rows. However, it will be noted that here the concept of polarization element is not fixed as in the case of the linear assemblies previously described. As shown in the figure, while for the coils B11, B12, B21, B22 the polarization elements correspond to magnets in columns 1 and 2 and columns 3 and 4, on the other hand, for the coil B31, the polarization elements group magnets in columns 2 and 3. This increases design flexibility, and allows very dense actuator arrangements capable of adapting to particular needs.

 Figure 7 also schematically shows magnetic field ferneture plates 31-S4, it being understood that the two plates 81 are connected by a magnetic path.

 Of course, the present invention is susceptible of numerous variants and modifications.

 For example, the polarizing elements instead of being permanent magnets could be flat coils with an iron core fed by continuous coding, which constitutes a means of complementary adjustment of the actuators making it possible to apply the same condition by modifying the continuous field of all polarization elements.

 On the other hand, in addition to the assemblies previously described in a linear row and in a matrix, other arrangements may be adopted. For example, the linear assembly could, with small variations in shape, be a ring assembly.

 It would then be useless to provide the parts for closing the magnetic field. Similarly, the matrix assembly could be an assembly in concentric rings.

 Furthermore, the modular actuator according to the present invention has been described in its application 9 the creat4on of a keyboard. In this case, the actuator is essentially used to provide a reaction force to an action on a keyboard key. Another application of this actuator would be to make it actually act as a motor, for example in the context of robotic applications where it is often sought to bring together a large number of activators in a small volume.

Examples of other possible variants of the invention include the following
- the moving coils can include iron bands inserted between the turns of the copper band wound in a flat coil in order to optimize the consumption characteristic as a function of the power supplied
- various types of potentiometric, optical, inductive position sensors, for example, can be used
- two or more moving coils of the same assembly can be mechanically and / or electrically coupled; ;
- the displacement of a coil can be used, via a contactor linked to this coil and associated with a multi-pole switch to cause a determined sequential actuation of several other coils of a given set

Claims (5)

REVENICATIONS  1. Assembly of flat linear actuator nodules, in which each module comprises  a flat moving coil (20, 22, 24; 40) mounted on slides (31, 32) allowing it to slide in its plane in a determined direction,  means (41, 42d for supplying current to the coil,  on each side of this coil and substantially parallel to it a flat means for applying a magnetic field in a direction orthogonal to the plane of the coil, this change being in a first direction in a first half of the surface occupied by the coil at rest and in the opposite direction in the second half, and  spacing means (71-75) for maintaining a gap observed between the means for applying the magnetic field,  characterized in that  only one magnetic field application means is present between two coils; and  closing means frame the means for applying extreme magnetic fields.  2. Module assembly according to claim 1, ca characterized in that the magnetic field application means are permanent magnets (10, 11; 101 ... 11-2) in the form of plates oriented in opposite directions in each half surface  3. Module assembly according to claim 1, characterized in that the means of application of the magnetic edge are flat coils oriented in opposite directions in each half-surface.  4. assembly of nodules according to claim 1, characterized in that it comprises  a position detector associated with each coil;  a central processor; and  interfaces for cotnmander the means of allnentation of each coil in response to the signals of the detectors processed by the processor.  5. Assembly of modules according to claim 4, characterized in that it comprises identical support chassis provided with spacing means relative to the vo'sins chassis, each chassis (50) comprising fixing means for carrying  - a magnetic field application core (43, 44),  - guide rods (32, 33) of an adjacent flat voice coil, and  - a position detector (6 wire) of the ladS coil.