DISPLAY MODULE FOR AN INSTRUMENT PANEL WITH FLUID MOVEMENT

• US 20140283732A1
• Filed: 11/13/2012
• Published: 09/25/2014
• Est. Priority Date: 11/14/2011
• Status: Active Grant

• Current Assignee: Sonceboz Automotive SA (Société industrielle de Sonceboz SA)
• Original Assignee: Moving Magnet Technologies
• Inventors: Heinrich, Sbastien
• Granted Patent: US 9,614,426 B2
• Time in Patent Office: Days
• US Class Current: 116/284
• CPC Class Codes: G01D 13/22 Pointers, e.g. settable pointer
• CPC Class Codes: H02K 37/14 with magnets rotating within the armatures
• CPC Class Codes: H02K 37/16 having horseshoe armature cores
• CPC Class Codes: H02K 7/116 with gears

Abstract

A display module has a two-phase motor which includes a rotor including N pairs of poles magnetised radially, in alternate directions, N being equal to 3 or 5, and a stator part including at least two W-shaped circuits made from radial pole teeth extending inwards from a peripheral closed belt and including a coil on a central leg of the W, said W-shaped circuits being arranged in such a way that when the central tooth of one of the W-shaped circuits is positioned facing a rotor magnetic transition, at least one central tooth of another W-shaped circuit is positioned facing a rotor magnetic pole. Said display module additional includes at least one specific mechanical interaction (between the rotor and the stator, comprising angular friction at a force that is substantially constant depending on the speed of the rotor relative to the stator, and at a value lower than the torque produced by the electromagnetic interaction between the rotor and the stator.

Claims

1. A display module having a two-phase non-lubricated motor comprising:

a rotor having N pairs of poles magnetised radially, in alternate directions, N being equal to 3 or 5;

a stator having at least two W-shaped circuits made from radial polar teeth extending inwards from a closed peripheral belt and having a coil on the central leg of the W, the W-shaped circuits being disposed so that, when the central tooth of one of the W-shaped circuits is situated facing a rotor magnetic transition, at least one central tooth of another W-shaped circuit is situated facing a rotor magnetic pole; and

at least one mechanical interaction between the rotor and the stator providing angular friction at a force that is substantially constant according to the relative speed of the rotor with respect to the stator, and with a value less than the torque produced by the electromagnetic interaction between the rotor and the stator.

2. A display module according to claim 1, comprising a housing secured to the stator, an assembly for the mechanical reduction of the speed of the motor, comprising an output wheel driving a pointer, and in that the mechanical interaction means consists of comprises at least one curved friction arm at a distal part of the output wheel and a sliding track secured to the housing.

3. A display module according to claim 2, wherein the friction arm is a polyoxymethylene polymer material.

4. A display module according to claim 2, wherein the sliding track comes into contact with an end of the friction arm.

5. A display module according to claim 4, wherein the end has a curved shape.

6. A display module according to claim 2, wherein there are N of the flexible friction arms, sliding ends of which are spaced apart by 360/N degrees, N being equal to 2 or 3.

7. A display module according to claim 1, wherein the stator comprises an annular belt, a set of teeth extending radially from an annular segment forming a shoulder fixed on the housing, having a mechanical connector of complementary shape.

8. A display module according to claim 1, wherein at least five of the teeth have identical lengths, measured radially.

9. A display module according to claim 1, wherein the length of the wound teeth is identical.

10. A display module according to claim 9, wherein the length of the coil and of the teeth carrying the coil are substantially equal but less than a cross section of a hollowed-out central area of the stator.

11. A display module according to claim 1, wherein the ends of the teeth are parallelepipedal in shape.