Control module for motor vehicles

A motor vehicle control module is described comprising a control unit with a carrier body, a circuit arrangement applied on the carrier body, a housing body that at least partially encloses the carrier body, at least one stamped grid with several stamped grid connections integrated in the housing body, and also the sensors and/or actuators with sensor elements and sensor connections and respectively actuator elements and actuator connections associated to the control unit. To reduce the space requirement and the costs and to improve the susceptibility to faults in the signal transmission from the sensors/actuators to the control unit, at least some of the sensors/actuators are situated in the control unit or in the immediate proximity of the control unit and are contacted by directly joining their respective sensor connections or actuator connections with stamped grid connections of the stamped grid of the control unit.

BACKGROUND OF THE INVENTION 
In motor vehicles, control modules are being used increasingly as control 
units and associated sensors/actuators for a variety of tasks and means of 
operation--in particular for the open-loop and/or closed loop control of 
travel-specific operations and processes. The sensors serve to acquire 
measured values and the actuators to operate final controlling elements 
(for instance, sensors are provided for measuring temperature, engine 
speed or pressure and actuators for operating on-off valves or motors) 
while the measured-value signals from the sensors and the output signals 
from the actuators are processed and evaluated by the control units of the 
motor vehicle. The sensors consist of a sensor element and sensor 
connections and the actuators consist of an actuator element and actuator 
connections. The control units are made up of a carrier element (printed 
circuit board) with circuitry arranged on it and a housing which encloses 
at least part of the circuit arrangement, where a stamped grid is 
integrated in the housing and is connected electrically to the circuit 
arrangement (for instance, by means of bond wires) to provide the terminal 
contacts and connector. The sensors and actuators that are normally fitted 
to the motor vehicle units (engine, gearbox etc.) through separate 
connecting parts (such as threads) and hermetically enclosed by a housing 
are connected to the separately arranged control units (for instance, in 
the engine compartment or in the interior of the motor vehicle) by means 
of connecting leads and connectors on the stamped grid of the control 
units. 
With these motor vehicle control modules comprising sensors/actuators and 
associated control units, it is a disadvantage that in order to connect 
the sensors/actuators to the control units numerous frequently very long 
connecting leads (cable tree) and numerous connectors are required for 
contacting. It is often difficult to locate these in the motor vehicle and 
they take up a lot of space and are very costly. Another disadvantage is 
that the reliability of signal transmission is not always guaranteed 
because of the long signal path from the sensors/actuators to the control 
units and because of the susceptibility to faults in the connecting leads 
and connectors. 
SUMMARY OF THE INVENTION 
The object of the invention is to provide a control module for motor 
vehicles of the type discussed above that avoids the disadvantages 
outlined above and has other advantageous features. 
This object is solved in accordance with the invention by a motor vehicle 
control module which comprises: a control unit with a carrier body, a 
circuit arrangement applied to the carrier body, a housing body at least 
partially enclosing the carrier body, and at least one stamped grid with 
several stamped grid connections integrated in the housing body; and, 
sensors and/or actuators formed respectively, of sensor elements and 
sensor connections and of actuator elements and actuator connections, 
assigned to the control unit; and wherein at least some of the sensors 
and/or actuators are arranged in the control unit or in the immediate 
proximity of the control unit, and these sensors and actuators are 
contacted by directly joining their sensor connections and actuator 
connector connections to stamped grid connections of the stamped grid of 
the control unit. 
Advantageous further developments of the invention are disclosed and 
claimed. 
In the control module described here, at least some (preferably all) of the 
sensors/actuators are contacted directly with the associated control unit 
by joining the connections of the sensors/actuators directly to the 
stamped grid connections of the control unit. With sensors/actuators 
situated in the immediate proximity of the control unit, this direct 
joining and contacting of the sensor/actuator connections is effected, for 
example, by means of spring elements or forked elements, fitted to the 
ends of the stamped grid connections, that encompass or enclose the 
sensor/actuator connections. This direct joining and contacting is 
effected preferably, however, by attaching the sensor/actuator elements to 
the stamped grid or stamped grids of the control unit and by making an 
electrical contact between the sensor/actuator connections and the stamped 
grid connections. In this preferred embodiment, the sensors/actuators, 
i.e., the sensor/actuator elements and the sensor/actuator connections, 
are, together with the stamped grids and the stamped grid connections 
respectively, enclosed by the housing body of the control unit. The number 
of sensors/actuators provided and the number of sensor/actuator 
connections to be contacted determines the number of stamped grids 
required in the control unit and the number of stamped grid connections on 
the respective stamped grid. 
Owing to the direct joining and contacting of sensors/actuators and control 
unit, the control module described has the following advantageous 
features: 
the complexity of connecting leads (cables) in the motor vehicle is reduced 
drastically, resulting not only in simplifications in manufacture but also 
in a reduction of the space required and the costs; 
contacting of the sensors/actuators is effected without connectors, leading 
to a further reduction of the space required and the costs; 
the susceptibility to faults in signal transmission is reduced and hence 
the reliability and electromagnetic compatibility of the control module is 
improved; 
in the event of the sensors/actuators being attached directly to the 
stamped grid connections of the control unit, no separate housing is 
required for the sensors/actuators.

DESCRIPTION OF A PREFERRED EMBODIMENT 
In accordance with FIGS. 1 and 2, the (gearbox) control module 1 integrated 
in the gearbox equipment space comprises a gearbox control device as 
control unit 10, several sensors 20 for measurement of rotational speed, 
for registering pressure and for identifying selector lever position, and 
actuators 30 for valve operation. 
The gearbox control unit 10 of control module 1 consists of a baseplate 11 
designed, for example, as a heat sink (and made, for example, of aluminum 
with the dimensions 160 mm.times.150 mm.times.14 mm), a carrier body 12 
designed, for example, as a printed circuit board joined to the baseplate 
11 thermally and mechanically by adhesion (and made, for example, of 
Al.sub.2 O.sub.3 with the dimensions 110 mm.times.80 mm.times.1 mm), a 
thick film circuit arrangement 13 on the carrier body 12 with numerous 
passive and active SMD semiconductor components potted with a molding 
compound 14, a housing body 15 (made, for example, of 
glassfiber-reinforced plastic) which encloses the circuit arrangement 13 
to protect the semiconductor elements, several (for example nine) stamped 
grids 17 integrated horizontally and vertically in the housing body 15 and 
joined to the circuit arrangement 13 by means of (for example) bond wires 
16, whereby these stamped grids can have a varying number of stamped grid 
connections 18 (for example, between 3 and 12 stamped grid connections), 
and a connector 19 through which the gearbox control unit 10 and the 
control module 1 are connected to the gearbox by means of connecting leads 
in such a way that the gearbox receives the output signal from the control 
module 1 or gearbox control unit 10 in the form of a control signal. Many 
of the stamped grids 17 make up the connector 19 of the gearbox control 
unit 10, and the rest of the stamped grids 17 take up and contact the 
sensors 20 and actuators 30. For the sake of clarity, only some of the 
stamped grids 17 are shown in FIGS. 1 and 2: stamped grids 17.1-17.4 for 
contacting sensors 20, stamped grids 17.5 and 17.6 for contacting 
actuators 30, and stamped grid 17.7 for forming a part of connector 19. 
Three rotary speed sensors 20.1, 20.2 designed as Hall sensors for 
registering rotational speed, four selector lever sensors 20.3 for 
identifying selector lever position and designed as Hall sensors, and one 
pressure sensor 20.4 for registering pressure are provided as sensors 20 
of the gearbox control module 1. The four selector lever sensors 20.3 are 
arranged on the stamped grid 17.3, two speed sensors 20.1 on the stamped 
grid 17.1, one speed sensor 20.2 on the stamped grid 17.2 and the pressure 
sensor 20.4 on the stamped grid 17.4. Also, an actuator 30.1 (made, for 
example, in the form of a proportional valve) joined to the stamped grid 
17.5 is provided and an actuator 30.2 (made, for example, in the form of a 
proportional valve) joined to the stamped grid 17.6. The selector lever 
sensors 20.3 activated by the selector lever shaft 2 detect the position 
of the gearbox selector lever according to the driver's command 
(parked/forwards/reverse), the two speed sensors 20.1 detect the engine 
output speed and the power output direction of encoder 3, the speed sensor 
20.2 detects the rotational speed of the engine, the pressure sensor 20.4 
registers the gearbox oil pressure, the actuator 30.1 controls the gearbox 
ratio and the actuator 30.2 controls the gearbox oil cooling. The 
information from sensors 20 and actuators 30 is sent on to the gearbox 
control unit 10 which processes this information and supplies a control 
signal. Each of the sensors 20 consists of a sensor element 21 as sensor 
body and three sensor connections 22, the actuators 30 of an actuator 
element 31 as actuator body and two actuator connections 32. 
The sensors 20 and the gearbox control device 10 are joined by placing (for 
example, by surface welding) the sensor elements 21 on the respective 
stamped grids 17 (two sensor elements 21.1 on stamped grid 17.1, one 
sensor element 21.1 on stamped grid 17.2, four sensor elements 21.3 on 
stamped grid 17.3, one sensor element 21.4 on stamped grid 17.4) and by 
contacting the respective three sensor connections 22 (22.1, 22.2, 22.3, 
22.4) with the corresponding stamped grid connections 18 (18.1, 18.2, 
18.3, 18.4). The conductive link between the actuators 30 (30.1, 30.2) and 
the gearbox control device 10 is effected by directly contacting the 
stamped grid connections 18 (18.5, 18.6) (which have forked/spring 
elements at their ends) of the corresponding stamped grid 17 (17.5, 17.6) 
with the two actuator connections 32 (32.1, 32.2) of the actuators 30 
(30.1, 30.2) that are immediately adjacent to the gearbox control device 
10--for instance, by enclosing or toothing the actuator connections by 
means of the forked/spring elements. 
The process for manufacturing the gearbox control module 1 from gearbox 
control device 10 and sensors 20/actuators 30 will now be described with 
reference to FIG. 3. Various steps in the process are shown in FIGS. 3a to 
3g: 
FIG. 3a shows a single stamped grid 17 of the gearbox control device 10 
with three stamped grid connections 18 made, for example, of a copper-tin 
alloy (such as copper alloyed with 6% tin). 
FIG. 3b shows the top view and FIG. 3c shows the side view of the stamped 
grid 17 partially coated with plastic 40 (a "primary coated part"). In the 
plastic 40 on both sides (on the upper side and on the lower side) at the 
level of the stamped grid connections 18, holes 41 are formed for 
centering; between the stamped grid connections 18, openings 42 are formed 
as separating aids; and on the upper side of the plastic 40, elevations 43 
("noses") and also on the side of plastic 40 elevations 44 are formed as a 
centering aid and to support the primary coated part. Furthermore, at one 
end of the stamped grid 17 and on the upper side of the plastic 40 there 
is a recess 45 for mounting a magnet 23 used for signal amplification and 
the sensor 20 (sensor element 21, sensor connections 22) bonded on it. 
FIG. 3d shows the stamped grid 17 partially coated with plastic 40 and with 
sensor 20 and magnet 23 integrated in the recess 45. 
In FIG. 3e, the recess 45 is filled with a silicon molding compound to 
protect the sensor connections 22; the end piece of the stamped grid 17 
opposite to the sensor 20 has been bent downwards by 90.degree.. 
In FIG. 3f, the stamped grid 17 prepared for placing in an injection mold 
is shown in top view; the grid is coated in the injection mold with a 
second plastic material (such as glass-fiber reinforced plastic, for 
example) to form the housing body 15. 
FIG. 3g shows a partial view of the finally assembled control module 1; the 
circuit arrangement 13 situated on the heat sink 11 and the printed 
circuit board 12 has been joined here to the stamped grid 17 and the 
stamped grid connections 18 by means of bond wires 16. The circuit 
arrangement 13 and the stamped grid 17 (and therefore also the sensor 20) 
are enclosed by housing body 15.