WO2002039799A1

WO2002039799A1 - Hybrid circuit for the control of electric motors that uses the cover of the reduction gear as heat dissipator

Info

Publication number: WO2002039799A1
Application number: PCT/ES2000/000426
Authority: WO
Inventors: Antonio Ferre Fabregas; Jordi Bigorra Vives; Ignacio Longares Felipe
Original assignee: Lear Automotive (Eeds) Spain, S.L.
Priority date: 2000-11-07
Filing date: 2000-11-07
Publication date: 2002-05-16

Abstract

The invention relates to a multichip circuit for the control of electromechanical devices actuating the displacement of moving parts in vehicles such as windows, sliding sunroofs, seats, backrests, etc., whose electromechanical devices generally comprise an electric motor (1) actuating a transmission housed in a box (3) that is provided with at least one cover (4), said electric motor (1) being connected to an electronic control circuit whose components (6) are arranged on an IMS plate that closes an opening to access the box (3). An aluminum plate (5) that dissipates the heat of said IMS plate is mounted externally and a conducting layer is mounted inside the box (3). Said plate carries the different components (6) which are mounted on the surface thereof. Only a connector (9) for the supply and communication of said electronic circuit, which is equipped for controlling other electric motors and the above-mentioned motor, protrudes to the outside, said connector being coupled on the box (3) of the motor.

Description

HYBRID ELECTRIC MOTOR CONTROL CIRCUIT USING THE REDUCING GEAR COVER AS

HEAT DISSIPATOR.

5 Field of the invention

The present invention concerns a multichip circuit suitable for control of one or more electromechanical devices for driving the movement of moving parts of vehicles, such as window windows, sliding roofs, seats, backrests, etc., whose electromechanical devices, which can also include locks, generally comprise an electric drive motor and a transmission and have an associated electronic control circuit of said electric motor, constituted according to the invention by means of said multichip circuit arranged on an IMS board and whose IMS board It is in turn arranged to cover at least in part an access opening to a box of said transmission, the components of said multichip control circuit located inside said box being conveniently protected, in general without encapsulating.

The multichip circuit of the invention can provide for example a mixed control of a window regulator device, as well as the lock of a door (or

20 central locking of several doors) and of a source of illumination of the automobile enclosure, associating it to said door as a module for the government of its possible opening or of the movement of the associated moon.

The multichip circuit assembly object of this invention and the electromechanical device to which it is associated thus constitute an integrated mechatronic module 25.

Throughout this memory, a chip will be understood as any encapsulated semiconductor device or more generally without encapsulation (preferred application), in which case the device will have electrodes on one of its surfaces. The semiconductor device may be of any kind such as a diode, transistor (eg MOS power), or a more complex module constituting an integrated circuit

The IMS plates, short for the English name "INSULATED METAL SUBSTRATE" (insulated metal substrate), consist of a relatively thick metal layer (usually aluminum), a very thin layer of an electrical insulator and another layer of a metal (usually copper) The copper and aluminum layers are separated by the electro-insulating layer. In this type of substrate, it is in the copper layer that the tracks that allow the conduction of the electric current are recorded and where the electronic components are arranged. Aluminum acts as a radiator of the heat generated in the copper layer by the electronic devices arranged there.

Background of the Invention The use of IMS boards as a substrate for electronic control circuits including in particular power devices has been known for several years. Thus, patents US-A-5,408,128, DE-A-19854180 (INT RECTIFIER CORP) and US-A-5,513,072 (KABUSHIKl KAISHA TOSHIBA), among others. The electromechanical devices referred to in this invention, for example an electric motor of a window window or car roof, require, for proper operation, a stop and start control in both directions of rotation for normal use, voluntarily ordered by a user, and an automatic stop device, or reversal of direction of rotation, in case of detecting, in a safe way, an overexertion of the electric motor during a closing operation, whose overexertion is indicative that the Luna has encountered an obstacle in her career. This automatic stop or reversal of the direction of rotation of the electric motor is of great importance for safety purposes since such an obstacle is often a part of the body of a person or pet occupying the vehicle or from outside it is peeking inside the vehicle . The drive of other moving parts of a vehicle, such as sunroofs, have similar requirements.

In various executions of the state of the art all these functions are controlled by a microprocessor (with a memory capable of accommodating various control programs) integrated in a control circuit that includes a power distribution stage to the electric motor and a detector device called hereinafter sensor, such as Hall effect or similar to detect the intensity consumed, speed and the direction of rotation of the electric motor shaft. This control circuit is generally arranged on a printed circuit board associated with an assembly formed by said electric motor and a transmission, generally of the screw-endless type and toothed crown. However, the association of such a printed circuit board with the electric motor and transmission assembly of each window, seat, backrest or the like represents a serious space problem due to the narrowness of the space available in the places where such devices must go housed, and also the printed circuit board must be protected, avoiding exposure to dirt, moisture and possible shocks. Another drawback is the need to include an electrical wiring connection between the printed circuit board and the electric motor.

On the other hand, patents EP-A-474904 (SIEMENS AG) and WO-A- 91/01060 (BROSE FAHRZEUGTEILE) refer to operating systems for electric motors for vehicle windows, comprising a drive unit that has an associated control circuit comprising a microprocessor, organized on a printed circuit board. Patents DE-A-3424581 (ASMO CO LTD) and EP-A-803628 (AUDI AG) refer to an electromechanical device for window regulators of a vehicle with a mechanism or protective means of anti-pinch for detection of such a situation of risk.

Recently, great interest has arisen in the possibility of integration, in the electromechanical devices (such as electric motors) of the electronic circuits and components that are used to control and actuate said electromechanical elements.

Thus, a detailed description of various mechatronic module technologies for power devices with control logic can be found in the publication "Technologies for Intelligent Power Mechatronics" by J. Will Specks, Motorola, Munich, March 28-29-2000. In many cases the proximity of electronic circuits to the electric motor is due to the need to reduce the distance traveled by electrical signals, especially high power, which can cause electromagnetic compatibility problems. At the same time, the electric motor is a source significant heat, which is a problem in many systems due to the increase in temperature generated and which can cause malfunction, and even the destruction of the electronic circuit itself. In addition, these electronic circuits must be protected from the environment to avoid any damage that may occur.

Brief exposition of the invention

In this invention a multichip circuit is presented for control of an electromechanical device for driving moving parts in a car, together constituting a mechatronic module integrated on a substrate that has the following main characteristics: the electronic components are arranged in an IMS substrate, with its metallic layer on the outside, which allows a better elimination of the heat generated by the electric motor; - the components are generally arranged without encapsulating (that is, in the form of a silicon die) on the copper layer where the tracks where the electric current circulates have previously been recorded, allowing the circuit to be compacted in a much smaller area , facilitating its installation in relation to the module; - the electronic components are connected to each other and to the circuit tracks by surface mounting techniques for VLSI circuits such as "wirebonding" or "flip-chip"; The IMS substrate itself where the electronic devices are located is provided as a cover, or part of it, of the transmission box of said module, leaving the aluminum layer on the outside and housing the copper layer with all electronic devices in inside; in this way, the elimination of heat is facilitated and the IMS substrate itself exercises the function of protecting electronic devices against environmental aggressions. In accordance with the above principles, using uncapsulated circuits and VLSI interconnection techniques mounted on a substrate that acts as both a radiator and protection, the circuit is compacted in a much smaller area, which allows a greater ease to integrate a greater amount from electronic devices in a circuit housed in the same electric motor that presents, in general, space limitations.

In the IMS substrate there is also a surface mount connector that allows the power supply of the circuit and communication with the outside through different input / output lines. The connector used must ensure a good seal of the module once it is arranged in the transmission box associated with the electric motor.

The electronic devices that are housed in the module are preferably sensors of various types, power transistors, an oscillator, a microprocessor / microcontroller, external signal conditioning circuits, external communication circuits and transistor control circuits. of power

Part or all of the electronic devices can be ASICs, that is to say specific application circuits made specifically for the mechatronic module to achieve greater compaction of the circuit.

The microprocessor is mainly used to execute an electric motor control algorithm. This algorithm allows to perform an anti-pinch function to avoid crushing a member or object interposed in the mobile panel race (moon or similar). That is, the detection of an impediment or difficulty in the rotation of the electric motor. The microprocessor can also, through the input / output lines, monitor and control other external devices.

The information generated by these sensors is communicated to the microprocessor. This information is used in the aforementioned algorithm. The different sensors introduced allow the use of different anti-pinch algorithms such as pulse counting or the detection of current peaks.

The sensors preferably used are magnetic sensors such as Hall or GMR effect, magnetic current sensors, vibration sensors and temperature sensors. These sensors allow to capture external signals that inform the direction of rotation and the speed of rotation of the electric motor, the mechanical movement of the module, the current supplied to the electric motor, false clamp alarms and temperature and overtemperature.

The signal conditioning circuits monitor the signals from external devices, such as sensors or switches and prevent the appearance of "glitches" or bounces at the microprocessor inputs.

The control circuits of the power transmitters allow the performance of electric motor control techniques based on the pulse width modulation (in English PWM). These techniques allow "soft start" and "soft stop" of the electric motor, that is to say the start and stop with stepped speed.

For a better understanding of the features of the invention, it will be described, from this point, on the basis of preferred embodiments of the invention, which are provided for illustrative purposes only, and therefore should not be No way interpreted with limitation.

Brief explanation of the drawings

The following detailed description cited includes references to the accompanying drawings, in which: Fig. 1 is an overall perspective view of the mechatronic module referred to in the present invention; Fig. 2 is a cross-sectional view of the transmission cover and housing assembly including the IMS plate and a surface mount connector, according to a first embodiment; Fig. 3 is an explanatory block diagram of a possible organization of the components of the multichip circuit of the invention; Figs. 4 and 5 show in plan and elevation respectively a possible realization of said multichip circuit with the connection of components to each other and to the IMS board by means of the "wirebonding"technique; and Figs. 5 and 6 are two views equivalent to the previous ones, where the union of the components of the multichip circuit with each other and the tracks of the IMS board has been carried out by means of a flip-chip technique. Detailed description of preferred embodiments

Referring firstly to Fig. 1, there is shown an electromechanical device intended for actuating and controlling the movement of moving parts of vehicles to which control the present invention relates. Such a device is of special application in the automotive industry for the controlled movement of moving parts of a vehicle such as window windows, sunroofs, seats, backrests, etc. The device comprises a motor 1 provided with a housing 2, whose motor 1 drives a transmission, itself known, housed in a box 3 provided with a cover 4, to which box 3 said motor housing 2 is fixed 1. As is explained above, the motor 1 is connected to an electronic control circuit arranged in an IMS board that constitutes precisely said cover 4, as can be seen better in Fig. 2. In said Fig. 2 it has been illustrated, in section , the box that houses the transmission, without representing the latter for clarity of the drawing, and for being alien to the object of the invention. It is appreciated that the cover 4 of said box 3 comprises an IMS circuit, with its thick aluminum layer 5 outside, in order to properly dissipate the thermal energy generated by the components (particularly power) of the circuit, and with said components 6 arranged in surface mounting and in this example connected to each other and to the tracks P1 ... Pn of the circuit by a wirebonding technique consisting of connecting cable bridges 7a. The thin electro-insulating layer 8 is also appreciated between said metallic outer layer 5 and the mentioned tracks P1 ... Pn and a surface mount connector 9, for the power and communications functions of said electronic circuit.

The aforementioned IMS plate in cover functions 4 may include two or more conductive faces, one of them supporting connection tracks and the second carrier of the circuit components, indicated above, in surface mounting.

An example of a possible embodiment of the multichip circuit according to the invention is shown schematically in Fig. 3, which generally comprises the following basic components: - a microprocessor 10 (next to which a clock 27 has been indicated), with at least one memory or specialized memory area 10a, capable of housing a control algorithm (optionally replaceable, by programming); - a temperature sensor 11 and one or more sensors of an operation parameter of the electric motor;

- several power devices or modules arranged in an assembly 12 for driving the electric motor;

- at least one device 28 (eg a power transistor) to avoid the effects of battery inversion;

- a circuit comprising the following sub-blocks:

- 13: input monitoring, for example, a button 20,

- 14: control of the power actuators, and - 15: control of communications with the outside through said connector 9, linked to one or more buses (By

Ex. CAN or LIN).

Although said last circuit can be organized in the form of the three aforementioned sub-blocks 13, 14, 15 differentiated, applied respectively to each of the three mentioned functions to be fulfilled, in a preferred embodiment of the invention it will be constituted by a single circuit ASIC 19.

The sub-block or input monitoring chip 13 will generally include an input adaptation stage and a signal filter stage. For its part, the communications control sub-block or chip will include, for example, transceivers: a CAN transceiver, an SCI transceiver, a controller of said CAN bus and a UART.

As indicated, the components of this circuit are arranged on the IMS plate without encapsulation, and said plate, acting as a cover of the cavity of the housing that houses the transmission is hermetically sealed, or at least by a seal and said uncapsulated components advantageously integrate a layer of protective epoxy resin

Below the microprocessor 10 and on the right side of the drawing of Fig. 3 different sensors are appreciated that may include the circuit and specifically an instantaneous intensity sensor 16 of consumption of an electric motor 21 driving a window regulator or sunroof (eg a Hall or GMR effect sensor that has been represented close to a group of actuating power transistors of said motor 21 ) capable of presenting a clamping problem in its performance. A position or speed sensor 17 and a temperature sensor 11 (of which there will be at least one) have also been indicated to ensure the integrity of the circuit. Depending on the algorithm used (loaded in memory 10a) one or more of the indicated sensors will be used. Finally, a vibration sensor 18 is provided to provide cooperation with said anti-pinch algorithm stored in the memory of the microprocessor 10, to discriminate false pinch detections from those valid detections.

The power supply devices 24 have been illustrated in the form of power FET transistors, according to a classic assembly (H-bridge) controlling, for example, the motor 21 for driving a window regulator of a door, the motor 22 for driving the lock of said door and a light source 23 of the interior of the vehicle (generally known in the sector as "courtesy light"), together constituting a module associable with said multifunctional door. However, the provision indicated as merely exemplifying should be considered. Each device or power supply block 24 also includes a resistor 25 for measuring the intensity consumed by each device, the measurement of which is read by the control of the power actuators 14 and can be used for the detection of accidental overcurrents, producing in this case the disconnection of the group of transistors avoiding their destruction, also allowing the elimination of protection fuses.

In Figs. 4 and 5, a multichip electronic circuit is shown with its components connected to each other and to the IMS board by means of the aforementioned "wirebonding" technique, while in Figs. 6 and 7 illustrate an electronic multichip circuit in all equivalent to the circuit of Figs. 4 and 5 except that the union of its components with each other and the tracks of the IMS board has been carried out using the flip-chip technique. The different components arranged on the IMS board and their functionality are identical in both cases. IMS board it comprises an aluminum substrate 5, heat sink generated by the circuit, on the outer face of the box 3 (see Fig. 2) and several conductive tracks P1 .... Pn on the inner face, the substrate 5 being isolated from the tracks P1 .... Pn by a layer of dielectric material 8 disposed therebetween. Next to one edge of the plate there is a connector 9, surface mounted with multiple connections. The circuit essentially comprises, as described with reference to Fig. 3: a control device formed by a microprocessor 10; an ASIC circuit 19 that includes sub-blocks applied to the functions of input monitoring, control of power actuators, and control of communications with the outside; several power supply modules 12, a temperature sensor 11 and a consumption intensity sensor of at least one power supply module 12. A voltage regulator 26 for feeding the different components also appears in Fig. 4.

In the exemplary embodiment of Figs. 4 and 5, most of the connections between the components and the tracks P1 ... Pn and between the components (generically designated with reference 6, Fig. 2) with each other are made using the wirebonding technique consisting of establishing cable bridges connection 7a, some of which, especially related to power distribution, are of greater section to resist the passage of higher intensity current.

In the exemplary embodiment of Figs. 6 and 7, the components 6 are connected to each other through the tracks P1 .... Pn and are connected to said tracks P1 .... Pn by the flip-chip technique consisting of small granules 7b of conductive material . In Fig. 6, practically the same components as in Fig. 4, described above, have been indicated, with the addition of a motor speed sensor 17, capable of providing information, together with the intensity sensor 16 to a more complex algorithm resident in the memory 10a of the microprocessor 10. The aforementioned algorithm stored for example in a "flash" memory 10a may be reformed including updates or improvements thereof, being programmable through the communications bus and supported on the chip or subblock 15 of communications control, cited. The inclusion of a voltage regulator 26 to feed the different components of the circuit being explained must be understood as optional given the possibilities of useful space on the IMS board by the capacity of the circuit, although said regulating element could be installed in a point on the outside of the set.

Claims

1.- Multichip circuit for control of electromechanical devices for driving the movement of moving parts of vehicles such as window windows, sliding roofs, seats, backrests, etc., whose electromechanical devices generally comprise an electric motor (1) provided with a housing (2), whose electric motor (1) drives a transmission housed in a box (3) provided with at least one cover (4), to whose box (3) said housing (2) of the electric motor (1) is attached , said electric motor (1) being connected to an electronic control circuit, CHARACTERIZED because the components of said electronic control circuit are arranged in at least one IMS (insulated metal substrate) plate which is arranged by closing at least in part an opening for accessing said box (3) of said transmission, the aluminum plate (5) having heat dissipation of said IMS plate being arranged on the outer face and at least one conductive layer on the inner face, carrier of the different components (6) in surface mounting, said components (6) being enclosed within said box (3) with only a power and communications connector (9) protruding from said electronic circuit, prepared outside to control other electric motors, in addition to the envelope whose box (3) is attached.

2. Multichip circuit according to claim 1, characterized in that said IMS plate is the cover of the access opening to the transmission-carrying box (3) (2).

3. Multichip circuit according to claim 1, characterized in that said IMS board includes at least two conductive faces one of them supporting connection tracks (P1 ... Pn) and the second carrier of the components (6) in assembly superficial.

4. Multichip circuit according to claim 2, characterized in that said electronic circuit comprises the following basic components: - at least one microprocessor (10) with at least one memory (10a) to house a control algorithm; - at least one temperature sensor (11) and at least one sensor (16, 17) of a motor operating parameter or controlled electric motors;

- various power supply devices (24) for motor drive or controlled electric motors; Y

- at least one device (28) to avoid the effects of battery inversion.

5. Multichip circuit according to claim 4, characterized in that said circuit further comprises: - a set that integrates sub-blocks (13) for monitoring inputs and (15) for control of communications with the outside through said said connector (9) linked to one or more buses (such as CAN, LIN) of the vehicle.

6. Multichip circuit according to claim 5, characterized in that it also includes a sub-block (14) for controlling the power actuators (24).

7. Multichip circuit according to claim 6, characterized in that it comprises three blocks (13, 14 and 15) differentiated according to each of the three mentioned functions to be fulfilled.

8. Multichip circuit according to claim 6, characterized in that said input monitoring sub-blocks (13); control of power actuators (14); and control of communications with the outside (15) are constituted by at least one ASIC circuit (19).

9. Multichip circuit according to any one of claims 4 to 8, characterized in that: said components (6) are arranged on the IMS plate without encapsulating; said plate, in function of cover (4) of the cavity that houses the transmission of the housing of one of the motors to be controlled is hermetically sealed, and the connection of the components to each other and to the tracks of the circuit is carried out by a technique of "wirebonding" or "flip-chip".

10. Multichip circuit according to one of claims 4 to 8, characterized in that: said components (6) are arranged on the IMS plate without encapsulation and integrate a layer of protective epoxy resin; the aforementioned IMS plate in cover functions (4) of one of the motors to be controlled integrates a closing joint, and the connection of the components to each other and to the tracks of the circuit is carried out by means of a wirebonding or flip technique. -chip".

11. Multichip circuit according to claim 4, characterized in that said sensor of an electric motor operating parameter is a sensor (16) of the instantaneous consumption intensity of at least one of the controlled electric motors (21) capable of present a problem of impingement in their performance.

12. Multichip circuit according to claim 4, characterized in that said sensor of an operating parameter of the electric motor is a sensor (17) of the axis rotation speed of at least one of the electric motors to be controlled (21) , such as a Hall effect sensor or a GMR sensor.

13. Multichip circuit according to claim 4, characterized in that it also includes a vibration sensor (18).

14. Multichip circuit according to one of claims 4 to 8, characterized in that the electronic components (6) are connected to the tracks (P1 ... Pn) of the circuit by means of a surface mounting technique for VLSI circuits.

15. Multichip circuit according to claim 6, characterized in that the power supply devices (24) comprise several groups of power FET transistors, each group controlling the motors (21) driving a window regulator of a door, the motor (22) for actuating the lock of said door and a light source (23) of the interior of the vehicle, together constituting a module associable with said multifunctional door.

16. Multichip circuit according to claim 15, characterized in that each power supply block (24) also includes a resistor (25) for measuring the intensity consumed by each device, the measurement of which is read by said control (14) of the power actuators and is useful for detection of accidental overcurrents, causing in this case the disconnection of the group of transistors (24).