WO1982001068A1

WO1982001068A1 - Electromechanical converter

Info

Publication number: WO1982001068A1
Application number: PCT/DE1981/000142
Authority: WO
Inventors: Gmbh Robert Bosch
Original assignee: Balcke G; Neu H; Herden W
Priority date: 1980-09-20
Filing date: 1981-09-16
Publication date: 1982-04-01
Also published as: EP0060859A1

Abstract

In the proposed converter, a first magnet (2) arranged on a diaphragm box (1), a magnetic field responsive element (3) and a second magnet (4) provided for the setting are arranged on one spindle inside the casing (5). For the balancing of the pressure detector, the position of the magnets (2, 4) is adjustable along the spindle (fig. 1). The converter itself may be arranged inside a pressure tight envelope. By setting the characteristics of the magnets (2, 4) and/or of the element (3), various physical magnitudes may be measured.

Description

Mechanical-electrical converter

State of the art

The invention is based on a converter according to the type of the main claim and the subordinate ones

Claims 5 and 6.

It is known to use transducers for measuring the pressure, in particular the intake air pressure, of an internal combustion engine serving to drive a motor vehicle, said transducers having a diaphragm can exposed to the pressure to be measured. In this case, a permanent magnet is arranged on one wall of the membrane box and in the vicinity of a magnetic field-sensitive element, for example a Hall IC, so that the distance from the permanent magnet to the magnetic-field-sensitive element varies with pressure-dependent deflection of the membrane, and thus its output signal is influenced. This output signal is then a measure of the pressure measured. The disadvantage of the proposed arrangement is that the spatial assignment of the permanent magnet and the magnetic field-sensitive element to one another cannot be changed, and different requirements for different pressure sensors cannot be adapted so that there is no possibility of adjusting the sensor in a simple manner when assembling the sensor.

Advantages of the invention

The pressure sensor according to the invention with the characterizing features of the main claim and the independent claim 5, on the other hand, has the distribution that the spatial position of the permanent magnet and the magnetic field-sensitive element can be adjusted to one another when assembling the pressure sensor, thereby adjusting the sensor to achieve a desired one Characteristic curve is possible, with a further permanent magnet being arranged coaxially for compensation purposes.

The sensor according to the invention with the characterizing features of the independent claim 6 also has the advantage that the difference between a measuring pressure and a reference pressure can be measured. The reference pressure can either be variable or an absolute pressure. This opens up a particularly simple possibility for controlling the injection of an internal combustion engine, since this injection usually takes place as a function of the amount of air that is passed through. However, the amount of air is proportional to the difference between the weighted atmospheric pressure and the absolute pressure in the intake manifold, so that a signal proportional to this, which corresponds to the load, can be determined directly with a single sensor without, as is known in the art, two separate ones Sensors required.

The same effect can finally be achieved in an advantageous manner according to the invention in that the sensor is surrounded by a pressure-tight housing, so that a measuring or reference pressure can be applied to the interior of the housing. Since, in any case, tight housings are used in electronic control devices in motor vehicles to protect the switching devices against moisture and the like, it is thereby possible in a particularly simple manner to display a differential pressure signal without any significant additional measures.

The transducer according to the invention with the characterizing features of claim 23 has the further advantage that a linear characteristic input variable / output variable is achieved in that the characteristic of the magnetic field-sensitive component is adjusted accordingly depending on the size to be measured. This makes it possible to operate display elements or control circuits directly with the encoder according to the invention without having to undertake a characteristic equalization.

Thus, in the case of measuring a gas pressure as a component, a field plate with a parabolic characteristic is used according to the invention line area is used, since in this way the hyperbolic dependence of the output signal on the deflection of the membrane is compensated. By suitable selection of the component or its range of characteristic curves, it is accordingly possible to generate a linear characteristic curve without any further components.

In order to measure the flow velocity of a gas, the negative pressure is measured at a narrow point of a Venturi tube. The quadratic dependence of the negative pressure on the flow velocity is compensated for by the hyperbolic dependence of the output signal of a linear magnetic field-sensitive element on the deflection of the membrane.

In the same way, according to the invention, the height is measured, for example in an aircraft, since the dependence of the air pressure on the height is also quadratic. In this case, it is additionally possible to measure the sinking / climbing speed of the aircraft in that the determined output signal is guided to a differentiating stage.

Overall, compared to the known mechanical measuring arrangements for flow speed, height and sink / climb speed, the absence of mechanical elements with friction means that absolutely hysteresis-free measurements are possible, the resolution of the measurement size being very suitable by suitable selection of the components and the transducer ring can be held. Compared to the known mechanical systems, the overall linear characteristic of the converter is also advantageous, which can only be achieved with great effort in mechanical systems. In addition, the few components used result in simple and therefore cost-effective production, and particularly temperature-stable behavior can be achieved by suitable measures specified in the subclaims.

drawing

The invention is illustrated in the drawing and explained in more detail in the following description. FIG. 1 shows a cross section through a first embodiment of a pressure serisor according to the invention; Figure 2 shows a cross section through a second embodiment of a pressure sensor according to the invention, Figure 3 shows a cross section through a third embodiment of a pressure sensor according to the invention; Figure 4 is a schematic diagram of an intake manifold of an internal combustion engine; Figures 5 to 9 cross sections and views of a fourth, fifth, sixth and seventh embodiment of a pressure sensor according to the invention; FIGS. 10 to 13 are diagrams for explaining the linearization of the overall characteristic of the transducers according to the invention; FIG. 14 shows an eighth exemplary embodiment of a converter according to the invention; FIG. 15 shows the circuit diagram of a first circuit for evaluating the output signal of a converter according to the invention; FIG. 16 shows a circuit diagram of a second embodiment of a circuit for evaluating the output signal of an invent according to the converter; FIG. 17 shows a circuit diagram of a third embodiment of a circuit for evaluating the output signal of a converter according to the invention.

Description of the embodiments

In FIG. 1, 1 denotes a membrane box, one wall of which carries a first permanent magnet 2. A magnetic field-sensitive element 3 is arranged in the vicinity of the first permanent magnet 2 and a second permanent magnet 4 is arranged in the vicinity of the side of the magnetic field-sensitive element 3 facing away from the first permanent magnet 2. The first permanent magnet 2, the magnetic field-sensitive element 3 and the second permanent magnet 4 lie in one axis, namely in the axis of a housing 5, which is equipped at both ends with blind holes, which are each provided with a fine thread 6 and 7, respectively. Disks 8 and 9 can be screwed into the fine threads 6 and 7, respectively. The disk 8 carries the other wall of the membrane box 1 on its side facing the housing interior. The second permanent magnet 4 is arranged on the other disk 9. The magnetic field-sensitive element 3 is finally connected to the housing 5 in a spatially fixed manner via a holder.

The deflection of the membrane box 1 is dependent on the pressure in the box and the pressure in the housing 5. With the housing 5 open, as shown in FIG. 1, the pressure sensor measures the difference between the measuring pressure in the membrane box 1 and the atmosphere.

As can easily be seen from FIG. 1, the relative position of the first permanent magnet 2 with respect to the magnetic field-sensitive element 3 can be changed by screwing the screw in or out Disc 8 can be varied. The same applies to the position of the second permanent magnet 4 relative to the magnetic field-sensitive element 3, which can be varied by screwing the disk 9 in or out.

To avoid mechanical play of the disks 8, 9 in the fine threads 6, 7, springs 10, 11 are finally provided, which are supported on the one hand on the side of the disks 8 and 9 facing the housing interior and on the other hand on the shoulders of the respective blind bores. When the discs 8 and 9 are screwed in, these springs 10 and 11 are preloaded, so that mechanical play is eliminated as a result.

In a further embodiment of the invention, the blind bores are not equipped with a fine thread and the disks are pressed into the bores in a snug fit.

In the second exemplary embodiment of a pressure sensor according to the invention shown in FIG. 2, an arrangement is also used to vary the relative position of the first permanent magnet 2 or the second permanent magnet 4 with respect to the magnetic field-sensitive element 3, in which the magnets 2 or 4 of disks 8 'or 9 'are carried in one axis with the magnetic field-sensitive element 3. In the embodiment according to FIG. 2, however, the disks 8 'or 9' rest on end surfaces of the housing 5 which are perpendicular to the axis and are screwed to the latter. The variation of the distance is achieved in that thin washers 12 and 13 are arranged between the washers 8 'and 9' and the housing 5, so that by a suitable choice of the thickness of the washers 12, 13 and a number of several thin washers the desired spatial distance of the elements 2, 3, 4 to each other is adjustable. In the third exemplary embodiment of a sensor according to the invention shown in FIG. 3, in deviation from the exemplary embodiment according to FIG. 2, the second permanent magnet 4 is not arranged directly on the disk 9 which can be screwed in and out, rather there is a further membrane box between the second permanent magnet 4 and the disk 9 14, which, as in the exemplary embodiment according to FIG. 3, can be designed as a closed absolute pressure can or which can be supplied with a reference pressure via a separate connecting piece.

The position of the first permanent magnet 2 and the second permanent magnet 4 relative to the magnetic field-sensitive element 3 is changed by the action of the measuring pressure on the membrane box 1 and the absolute or relative reference pressure on the further membrane box 14. The output signal of this element 3 therefore depends on the measuring pressure and the reference pressure. If the second diaphragm box 14, as shown in FIG. 3, is designed as an absolute pressure cell, the arrangement according to FIG. 3 is particularly suitable for use in the control of ignition and injection systems in motor vehicles. In these systems, the intake manifold vacuum or intake manifold absolute pressure in conjunction with the atmospheric pressure is usually used as a control variable. 3, the output voltage U _{A of} the magnetic field-sensitive element 3 is:

ü

where α and ß are constants and P _{atm is} the atmospheric pressure and P _{u is} the intake manifold vacuum. The constants α and ß can be varied independently of one another the can steepness and magnetic data can be set in wide ranges so that a desired degree of height correction is achieved in accordance with the measured atmospheric pressure. For example, if you choose α = ß, you get:

where P _{s is} the intake manifold absolute pressure. In the case of an injection system for an internal combustion engine, the following applies to the injection quantity EM, which is proportional to the quantity of air m:

where A and B are constants and B is usually on the order of 0.05 to 0.10. As can be readily seen, the sensor according to FIG. 3 immediately results in a signal corresponding to the air quantity m and thus the injection quantity EM.

It goes without saying that the arrangement according to the figure in which two membrane boxes are used can also be designed in the manner shown in FIG. FIG. 4 shows a basic diagram of an intake manifold 20 of an internal combustion engine. The direction of the intake air is indicated by arrows 21. In the intake manifold 20, a throttle valve 23 is shown rotatable about a fulcrum 22 in three positions 23a for a closed throttle valve, 23b for a half-opened throttle valve and 23c for a fully open throttle valve. Finally, 20 ports 24, 25 are arranged on the intake manifold in such a way that when the throttle valve 23a is closed, the port 24 is connected to the part on the engine side and the port 25 is connected to the part of the intake manifold 20 facing away from the engine, in each case based on the position of the throttle valve 23. If the throttle valve 23 is opened and it is in the position 23b, this relationship is reversed, ie the connection 24 is now connected to the part of the intake manifold 20 facing away from the engine and the connection 25. This means that the difference between the pressure values measured at the connections 24, 25 is positive in one case and negative in the other case. When the throttle valve 23c is fully open, the difference between the pressure values measured at the connections 24, 25 is finally practically zero, since due to the position of the throttle valve 23 there is no longer any pressure difference.

If the connections 2k, 25 are now connected to the diaphragm sockets 1, 14 of the exemplary embodiment according to FIG. 3, in addition to the analog signal for the pressure difference between the atmosphere and the intake manifold, a digital signal can be generated for the position of the throttle valve in each case , because, as already mentioned, the pressure difference is once positive, once negative and once zero. The same effect can be achieved with an embodiment of a pressure sensor according to the invention according to FIG. 5, in which one pressure is introduced via a connection 30 into the measuring diaphragm socket 1 and the other pressure via a connection 31, which is located in the wall of the latter Case pressure sealed housing 5 befin det. In this case too, the deflection of the permanent magnet 2 is dependent on the pressure difference at the connections 24, 25, which are connected to the connections 30, 31 of the pressure sensor.

Finally, it is also possible to arrange a pressure sensor as shown in FIGS. 1, 2, 3 and 5 in a further housing 32, as is indicated, for example, in FIGS. 6a, b and c. The housing 32 is also designed to be pressure-tight. In the housing 32 there are two connections 30a and 31a, which in the exemplary embodiment shown in FIG. 6 are connected to the membrane socket 1 via a line 34 or to the interior of the housing via a line 33. Corresponding to the sensors according to FIGS. 3 and 5, the connections 24, 25 of the suction pipe 20 are connected to the connections 30a, 31a or vice versa. The deflection of the permanent magnet 2 is in turn a function of the pressure difference, so that a signal corresponding to the throttle valve position is in turn generated.

In the current electronic control systems for internal combustion engines in motor vehicles, the control device is surrounded by a housing which protects the control device against moisture and the like. If this housing is now made pressure-tight, it can serve as housing 32, as shown in FIGS. 6a to c. Such Arrangement with an electronic control unit, which is accommodated together with a pressure transmitter in a common housing, is described below. It is therefore possible overall to achieve an arrangement with only little additional effort (seal and additional connection) with which the measurement of the pressure difference on the intake manifold 20 is possible in the manner described above for controlling engine sizes.

In the arrangement according to FIGS. 7 and 8, the pressure transducer with its foot part 26, which is kept smaller in outer diameter and which contains the threaded washer 9 and the helical spring 11, is inserted into a plastic press designed as an intermediate base 28, which together with an upper part 36 also pressed from plastic includes the pressure transmitter according to Figure 1 and if necessary can be sealed airtight and moisture-proof. The connection 30 of the pressure transducer protrudes into the longitudinal bore 27 of a connection piece 38 formed on the upper part 36, onto which a connecting hose, not shown, can be pushed, with which the longitudinal bore 27 of the connection piece 38 can be connected to the intake pipe of an internal combustion engine, not shown, and can then bring about the negative pressure prevailing in the intake pipe in the double diaphragm can 1. The connection 30 is sealed from the outside air pressure prevailing in the upper part 36 by a rubber ring 39, the penetration of moisture being prevented by a disk-shaped Teflon element 35 inserted into a pressure compensation opening 29. An annular sealing bead 37 and an annular groove 37a receiving this sealing bead are provided on the superimposed end faces of the upper part 36 and the intermediate base 28. The intermediate floor 28 of the housing enclosing the pressure sensor serves as the lid of a pot-shaped base part 40, which is also pressed from plastic and contains a cutout 43 that runs from the top 41 to the bottom 42. This is closed at the bottom by a metal plate 44, which serves as a heat sink for a semiconductor circuit 45. This is, for example, a transistor coil ignition device, the switching time of which is shifted as a function of the pressure prevailing in the intake pipe and thus leads to a pressure-dependent adjustment of the ignition time. For pressure-dependent adjustment, a Hall IC, preferably serving as a magnetic field-sensitive element 3, is provided with three connecting tabs 46, each of which is soldered to one of three thin, leaf-shaped connecting lines 47. These connecting lines 47 are extrusion-coated in the manner shown in FIG. 7 from the plastic of the base part 40 in such a way that their angled end section 48 protruding into the recess 43 forms a soldering point for a flexible connecting lug 49, which leads to the semiconductor circuit 45. At the. Opposite edge of the semiconductor circuit 45 are provided in the material of the lower part 40 injected tongues 50 which are connected to the semiconductor circuit 45 at their end portions projecting into the recess 43 via a connecting wire 51 (FIG. 7) and at their other end portion 52 into the inner cavity 53 protrude into a one-piece molded on the bottom part 40 socket 54, where they can be connected by a suitable connector sleeve.

In the exemplary embodiment shown, the semiconductor circuit 45 is cast airtight and moisture-tight with a silicone gel layer. This potting layer 55 also includes a large part of the connecting wires 49 and 51. As can be seen from the axial section shown in FIG. 7, 28 sealing ribs 56, 57 are arranged on the underside of the intermediate base, which engage in suitable recesses 58, 59 on the upper side 41 of the lower part 40 and are tightly connected to the latter by adhesive.

The particular advantage of the above-described combination of an electronic and an electronic-mechanical construction device according to the invention into a unitary assembly is that this combination can take place in a space-saving and assembly-safe manner, which results in high long-term stability and low costs.

FIG. 9 shows a modified embodiment of the invention, which differs advantageously from those according to FIGS. 7 and 8 in that the vacuum sensor shown in FIG. 9 can be installed upside down and is freely accessible for testing and adjustment purposes, as long as the very simply constructed, upper part made of plastic indicated in FIG. 9 at 60 has not yet been put on. In this embodiment variant, the supply of the pressure or of the negative pressure prevailing in the intake pipe of an internal combustion engine, not shown, takes place - in contrast to the exemplary embodiment according to FIGS is guided to a central annular space 65, into which the connection 30 of the pressure transmitter, which is used for connection to the double diaphragm box 1, projects. The metal housing 5 of the pressure sensor, which is otherwise designed as shown in Figure 1, is by several supported on the top of the intermediate floor 62, resiliently formed tongues 66; it is held when placing the upper housing part 60 by a foam rubber cushion 67 placed on the foot part 26 of the pressure transducer so that the pressure transducer can withstand even the strongest shaking stresses occurring during operation on motor vehicles.

The dependence of the deflection s of the membrane of the pressure cell 1 on the measuring pressure p is linear, as is shown schematically in FIG. 10 by the course 120. In contrast, the induction B at the location of the component 3 has a hyperbolic profile 121 as a function of the deflection s, as can be seen from FIG. 11. The amount of induction B, which is exerted on the component 3 by the fixed compensation magnet 4, is independent of the deflection s, as can be seen from the curve 122 in FIG. 11. The magnets 2, 4 and the component 3 are arranged in one axis. If the compensation magnet 4 were now moved along this axis, the course 122 in the ordinate direction in FIG. 11 would also change.

If one took a component with a linear characteristic as component 3, the combination of the curves 120, 121, 122 would result in a non-linear curve overall. In order to compensate for this non-linear course when measuring the absolute or differential pressure, a field plate is provided according to the invention as component 3, which has an area 124 with a parabolic course in at least part of its characteristic curve 123, as is shown schematically in FIG. The overall characteristic curve of the encoder now results from a combination of the curves 120, 121, 122, 123, the hyperbo lical course 121 of the induction at the measurement site is compensated for by the parabolic course in the area 12U of the field plate. Overall, this results in a linear characteristic curve 125 for the related resistance R / R _{o of} the field plate over the measuring pressure p, as shown in FIG. When the compensation magnet 4 is taken into account, the position of the course 125 in the ordinate direction is variable, as is indicated by the course 126 shown in broken lines.

If a component with a linear characteristic curve, for example a linear Hall IC, is used for the magnetic field-sensitive component 3 instead of a field plate, an absolute pressure arrangement can advantageously be used for measuring the height, for example in an aircraft. According to the barometric height formula, the pressure decreases with increasing height, the non-linearity of the relationship between height and pressure being compensated for by the hyperbolic curve 121 according to FIG. 11. In this case, a linear component 3 gives a linear output signal for the height.

To measure the flow velocity of a gas, according to the invention, an indirect measurement is carried out via the negative pressure at a constriction 130 of a Venturi tube 131, as is shown schematically in FIG. 14. The connector 30 of the pressure cell 1 is connected directly to the constriction 130 of the venturi tube 131 and the interior of the housing 5 is connected to the atmospheric external pressure.

The negative pressure p _u at the constriction 130 of the venturi tube

131 is proportional to the square of the flow velocity (v ² ). Now used as a magnetic field sensitive Lich component 3, in turn, one with a linear characteristic, for example a Hall IC, the nonlinear, namely quadratic characteristic of the measured variable flow velocity is compensated for by the hyperbolic curve 121 according to FIG. 11, and once again using such a linear component 3 a linear overall characteristic of 14 according to FIG. 14.

FIG. 15 shows an evaluation and display circuit for a Hall IC. From terminal 115, a first line leads to a terminal 150 connected to operating voltage U _B and a second line via a display instrument 152 to the tap of a potentiometer 153, which is connected between operating voltage and ground and a third terminal to ground. The first and the third connection serve for the power supply of the Hall IC, while the measurement signal can be removed via the second connection. The measurement signal is displayed directly on the display instrument 152. In the measurements of the height and the flow velocity described in detail above, in which a linear Hall IC is expediently used, this measured variable can therefore be read directly on the display instrument 152.

If a transducer according to the invention, as described above, is used to measure the height, for example in an aircraft, the rate of descent / climb of the aircraft can advantageously be detected and displayed using an evaluation and display circuit as shown in FIG. 6 . For this purpose, a differentiating element, consisting of the resistor 155, a capacitor 154 and an operational amplifier 156 is connected to the display instrument 157. Thereby is over the number adornment limb 154, 155, 156 formed the first time derivative of the altitude and thus the sinking or climbing speed of the aircraft and displayed on the display instrument 157.

An expedient combination of these two circuits is shown in FIG. 17, the circuit part designated by the reference numbers 152, 153 being used, as already explained, to display the height on the display instrument 152. The measurement signal is also passed through the differentiating capacitor 154 and a resistor 158 to an operational amplifier 156, which is bridged by the resistor 155 and a capacitor 159. Between the operational amplifiers 156, 160 there is the display instrument 157 for the sinking / climbing speed of the aircraft, the one input of the operational amplifier 160 continuing to be led to the potentiometer 153 and, on the other hand, connected to ground via a capacitor 161. Once the measurement signal has been directly evaluated, the altitude is displayed on the display instrument 152, and the evaluation via the differentiator 155, 154 causes the aircraft's sink / climb speed to be displayed on the display instrument 157.

Claims

Expectations

1. Mechanical-electrical converter with a housing, in the axis of which are arranged close to one another one behind the other a) a membrane box (1) exposed to a measuring pressure, one wall of which carries a first permanent magnet (2), b) a magnetic field-sensitive element (3), c ) a second permanent magnet (4) characterized by the following features: d) the housing (5) has two bores lying in the axis; e) disks (8, 9) are inserted into the bores, one of which carries the other wall of the membrane box (1) and the other carries the second permanent magnet (4).

2. Converter according to claim 1, characterized in that the bores are each provided with a nut thread, in particular fine thread (6, 7) and the disks (8, 9) are screwed into the fine thread (6, 7).

3. Converter according to claim 2, characterized in that in the housing (5) springs (10, 11) between the disks (8, 9) and supports in the housing (5) are arranged.

4th Transducer according to claim 1, characterized in that the disks are press-fit into the bores.

5. Mechanical-electrical converter with a housing, in the axis of which are arranged close to one another one behind the other a) a membrane box (1) exposed to a measuring pressure, one wall of which carries a first permanent magnet (2); b) a magnetic field sensitive element (3); c) a second permanent magnet (4) characterized by the following features d) the other side of the membrane disc (5) and the second permanent magnet (4) are each arranged on a disk (8 ', 9'); e) the disks (8 ', 9') are screwed onto end faces of the housing (5) perpendicular to the axis; f) between the washers (8 ', 9') and the end faces are thin washers (12, 13).

6. Mechanical-electrical transducer with a housing, in the axis of which are arranged close to one another one behind the other a) a measuring membrane exposed to a measuring pressure (1), one wall of which carries a first permanent magnet (2); b) a magnetic field sensitive element (3); c) a second permanent magnet (4), characterized by the following features d) a further, an absolute or relative reference pressure exposed membrane box (1L) is arranged in the axis, one wall of which carries the second permanent magnet (4).

7. Transducer according to claim 6, characterized in that the housing (5) has two bores lying in the axis and in the bores disks (8, 9) are inserted, one of which is the other wall of the membrane box (5) and the other carries the other wall of the further membrane box (14).

8. converter according to claim 7, characterized in that the bores are each provided with a nut thread, in particular fine thread (6, 7) and the disks (8,9) are screwed into the fine thread (6, 7).

9. Transducer according to Claim 8, characterized in that springs (10, 11) are arranged in the housing (5) between the disks (8, 9) and supports in the housing (5).

10. Converter according to claim 7, characterized in that the discs are pressed into the bores in a snug fit.

11. Transducer according to claim 6, characterized in that the other side of the membrane box (5) and the other side of the further membrane box (14) are each arranged on a disk (8 ', 9'), the disks (8, 9 ' ) are screwed onto end faces of the housing (5) perpendicular to the axis and are screwed between the disks (6 ', 9') onto end faces of the housing (5) perpendicular to the axis and between the disks (8 ', 9') ) and thin washers (12, 13) on the end faces.

12. Transducer according to one of the preceding claims, characterized in that the housing (5) or a further housing (32) surrounding the housing (5) is designed to be pressure-tight and is provided with a first connection (31a) that one of the diaphragm boxes (1 , 14) is provided with a further connection (30a) and that the connections (30a, 31a) are connected to the intake manifold (20) above (24) or below (25) the throttle valve (23).

13. Converter according to claim 12, characterized in that the further housing (32) also serves to accommodate an electronic control unit for the internal combustion engine.

14. Transducer according to one of the preceding claims, characterized in that a housing (32, 60) enclosing the pressure transmitter is designed as a cover of a pot-shaped base part (40) in which an electronic switching device (45), in particular an ignition adjusting device which operates as a function of pressure, runs - and moist-

15. Transducer according to claim 14, characterized in that between the housing enclosing the pressure sensor (32, 60) a plastic intermediate floor (28) is arranged and that in the bottom part (40) molded, for connecting the electronic switching device (45) serving Connection lines (47) are formed, which are inserted through the intermediate floor (28, 62) and protrude into the interior of the upper housing part (36, 60).

16. Converter according to claim 15, characterized in that the connection (30) of the pressure transmitter through a connection (30) surrounding seal, in particular ring seal (39) is sealed off from a connecting piece (38) which contains a longitudinal bore (27) with which the diaphragm box (1) is in pressure connection.

17. Converter according to one of claims 14 to 16, characterized in that a connecting piece (38) is integrally formed on the upper part (36) made of plastic.

18. Converter according to one of claims 14 to 16, characterized in that a connecting piece (63) is integrally formed on the intermediate floor (62).

19. Converter according to one of claims 14 to 18, characterized in that in the bottom part (40) made of plastic connection lugs (47, 50) are formed, the end portions of which serve to accommodate the electronic switching device (45) cavity (43) of the bottom part (40) protrude.

20. Converter according to claim 19, characterized in that on the bed part (40) is formed a plug socket (54) in which the outwardly guided, tongue-shaped connecting lugs (50) are accessible.

21. Converter according to one of claims 17 to 20, characterized in that the cabbage space (43) serving to receive the switching device (45) is designed as a recess which is continuous from the top (41) to the underside (42) of the bottom part (40) which is closed at the bottom by a metal plate (44).

22. Transducer according to claim 21, characterized in that the cavity (43) is at least partially poured out with a moisture-proof casting compound (55), in particular from silicone gel.

23. Mechanical-electrical converter according to one of the preceding claims for measuring different types of physical quantities with a pressure cell and at least one magnet and a magnetic field-sensitive component, the relative position of which can be changed as a function of an expansion of the pressure dose, characterized in that the characteristic curve of the component (3) and / or magnets (2, 4) is set so that there is a linear overall characteristic of the transducer with respect to the quantity to be measured (pressure, flow speed, height, sink / climb speed).

24th Transducer according to Claim 23, characterized in that the quantity to be measured is a gas pressure and the component (3) is a field plate operated in the parabolic characteristic area (124).

25. Converter according to claim 23, characterized in that the variable to be measured is a flow velocity of a gas which is measured via the negative pressure of a Venturi tube (131) and the component (3) is a linear Hall IC.

26. Transducer according to claim 23, characterized in that the measuring variable is a height which is measured via the air pressure, the pressure nozzle (1) being evacuated and the component (3) being a linear Hall IC.

27. Converter according to claim 26, characterized in that the variable to be measured is a sink / climb rate and that the Hall IC is followed by a differentiating stage (151, 154).