CN106052940B

CN106052940B - Device for determining pressure and method for producing the same

Info

Publication number: CN106052940B
Application number: CN201610217752.2A
Authority: CN
Inventors: F·克洛普
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2015-04-10
Filing date: 2016-04-08
Publication date: 2020-11-03
Anticipated expiration: 2036-04-08
Also published as: JP6587972B2; CN106052940A; JP2016200594A; DE102015206470A1

Abstract

The invention relates to a device for determining a pressure and a method for producing the same. The device is configured with: a housing having a cavity and a first sealing structure; a sensor device having a second sealing structure in engagement with the first sealing structure such that a mouth of the cavity is closable by the sensor device, wherein the sensor device is configured for determining a pressure loading the cavity; and a sealing device disposed at least partially in the cavity and configured for compressing the second sealing structure against the first sealing structure by applying a compressive force to the sensor device.

Description

Device for determining pressure and method for producing the same

Technical Field

The invention relates to a device for determining a pressure and to a method for producing a device for determining a pressure. The invention relates in particular to a pressure sensor, preferably a high-pressure sensor, having a self-sealing construction technique and a connection technique. A "high-pressure sensor" is to be understood to mean, in particular, a sensor which is designed to determine a pressure of more than 2000 bar, preferably more than 2500 bar, particularly preferably more than 3000 bar, wherein the high-pressure sensor is advantageously not damaged. 1 bar corresponds to 100000 pascals.

Background

In hydraulics and in many fields of process technology, pressure sensors, i.e. devices for determining pressures (in particular pressures greater than 50 bar), play an important role. In particular, in the construction of motor vehicles, such devices are used in various systems, for example in direct fuel injection devices and in driving dynamics control devices. So-called piezoresistive high-pressure sensors are generally used here, which have particularly precise and robust properties and can be produced with relatively low outlay.

In piezoresistive pressure sensors, there are resistances sensitive to elongation on a suitably designed steel diaphragm, which are used to connect a wheatstone bridge. The pressure to be determined exerted on the steel diaphragm causes the steel diaphragm to deform. And therefore may cause elongation of the material of the electrical resistance on the surface of the steel diaphragm. The electrical resistance is arranged in such a way that elongation or contraction can be sensed. The resulting wheatstone bridge (also called resistance bridge) detuning is proportional to the given pressure in the case of small membrane deflections of the steel membrane and can be evaluated by suitable electronic means.

DE 102009025486 a1 describes a two-part pressure sensor, the two parts of which are fixed to one another by means of a weld seam. The first part is a housing with an external thread which is not in contact with the fluid whose pressure is to be determined. The second part has a measuring section, the deformation of which caused by the pressure to be determined is measured and evaluated to determine the pressure to be determined.

Disclosure of Invention

The invention discloses a device for determining a pressure and a method for producing a device for determining a pressure.

Accordingly, the present invention provides a device for determining a pressure, comprising: a housing having a cavity and a first sealing structure; a sensor device having a second sealing structure, which is in engagement with the first sealing structure in such a way that by means of the first sealing structure and the second sealing structure a mouth of the cavity can be closed by the sensor device, wherein the cavity is loaded with a pressure to be determined, the sensor device being configured for determining the pressure to be determined; and a sealing arrangement arranged at least partially, preferably completely, in the cavity and configured for pressing a second sealing arrangement onto the first sealing arrangement by applying a pressing force onto the sensor arrangement.

The pressure to be determined is in particular the pressure of a fluid that can be introduced into the cavity and is loaded with the pressure to be determined, whereby the cavity is also loaded with the pressure to be determined. The housing of the device may also be referred to as a pressure nipple. The sealing means and the sensor means may be referred to as a mating part. The mouth of the cavity is understood to be the through-flow connection from the cavity to the outside of the device. A through-flow connection is understood to be a path that can receive fluid to pass from one location to another.

Furthermore, the invention provides a method for producing a device for determining a pressure, comprising the following steps: constructing a housing having a cavity and a first sealing structure; constructing a sensor device having a second sealing structure; introducing the sensor device into the cavity in such a way that the mouth of the cavity can be closed or already closed by the sensor device; the sealing arrangement with the second sealing structure is arranged at least partially, preferably completely, in the cavity, such that the sealing arrangement presses the second sealing structure against the first sealing structure by applying a pressing force to the sensor arrangement.

The invention is based on the following recognition: the production of a pressure sensor consisting of a plurality of components advantageously enables the individual components to be produced separately and also optimally with regard to the required production effort. Furthermore, the individual components produced can be connected to one another in such a way or in such a way that deformation of the components which determines the pressure is minimized. High voltage sensors often require a new part precision of about 0.5% FS (Full Scale; english: Full Scale), for example. In order to achieve this accuracy, it is advantageous if no offset of the zero signal of the pressure sensor, i.e. of the device for determining the pressure, occurs when the individual components of the pressure sensor are joined. It is furthermore particularly advantageous that the device according to the invention is self-sealing, i.e. the higher the pressure applied to the cavity, the more tightly the sensor device closes the mouth of the cavity.

Furthermore, the device according to the invention eliminates welds that are loaded in tension, which increases the strength of the device. Furthermore, the design of the device according to the invention ensures that both when the device is produced and when the device is removed or installed at the site of use: the sensor device of the device is better mechanically decoupled from external influences.

Furthermore, the advantages of the device according to the invention described herein are independent of the specific method used for manufacturing the sensor device of the device. An embodiment of the sensor device with a thin-layer-based measuring cell is described below, which shows one of several examples.

Advantageous embodiments and improvements result from the following description with reference to the figures.

According to a preferred refinement, the sensor device has: a diaphragm in communication with the cavity; and a measurement unit configured to determine a pressure to be determined to load the cavity based on the deformation of the diaphragm. The measuring unit can in particular have a wheatstone bridge. The diaphragm can be designed as a thinned section of a one-piece base body of the sensor device, which can be made of steel, for example. The pressure to be determined can thus be determined particularly accurately.

According to a further preferred development, the sealing device is mounted on the housing under the influence of a pretensioning force such that, as a result of the pretensioning force, the sealing device is pressed against the sensor device in such a way that the second sealing structure is pressed against the first sealing structure which is in engagement with the second sealing structure. The pressure-tight connection of the sensor device to the housing is thus ensured even in the absence of additional pressure or with only a small additional pressure, so that no pressure loss occurs at the first mouth of the cavity, but rather the first mouth is pressure-tightly closed by the sensor device. Thus, in other words, the device is self-sealing.

According to a further preferred development, the sealing device is fixed to the housing by means of at least one weld seam. It is thus possible to achieve a fixed connection of the sealing device to the housing.

According to a further preferred development, the first sealing structure has a first external cone and the second sealing structure has a first internal cone, wherein the first internal cone can be pressed onto the first external cone in a form-fitting manner in order to close the mouth of the cavity. That is, the first inner cone portion may be press-fit into the first outer cone portion in a pressure-tight manner. The mouth leading out of the cavity of the housing can thus be closed particularly tightly. "external taper" is to be understood in particular as meaning the side of a conical recess in the element. "internal taper" is to be understood to mean, in particular, a tapered outer surface of the element.

According to a further preferred development, the sensor device has a third sealing structure which is designed to cooperate with the sealing device for sealing purposes. The third seal structure may have or consist of a second external conical portion. The third sealing structure may additionally or alternatively have or consist of a sealing edge. The sealing edge is also referred to as the snap edge. This makes it possible to achieve a particularly pressure-tight connection between the sensor device and the sealing device.

According to a further preferred refinement, the third sealing structure of the sensor device has a second external cone portion, wherein the sealing device has a fourth sealing structure configured as a second internal cone portion, which can be brought into engagement or is already brought into engagement with the third sealing structure. In particular, the second internal taper can be pressed (for example by pretensioning) onto the second external taper, i.e. the second internal taper can be pressed into the external taper. The pressure tightness between the sensor device and the sealing device is thus further improved.

According to a preferred development of the production method according to the invention, the sealing device is pressed into the cavity when the sealing device is arranged or introduced into the cavity, in order to fix the sealing device in the cavity and in order to apply a pressing force to the sensor device, in such a way that a pretensioning force exists between the sealing device and at least the sensor device (and optionally the housing). It can be provided that the sealing device is fixed in the cavity of the housing only by means of the described pretensioning force, i.e. that an interference fit exists. The interference magnitude of the interference fit is preferably selected as follows: the connection between the sealing device and the housing is still pressure-tight when the cavity is inflated under the application of the pressure to be determined. The interference can be adapted to the desired pressure depending on the area of use of the device according to the invention.

According to a further preferred development, the sealing device is engaged with a predetermined pretensioning force into the cavity and is fixed to the housing by means of a weld seam, when the sealing device is arranged or introduced into the cavity, in order to fix the sealing device in the cavity and in order to apply a pressing force to the sensor device. A pressure-tight connection between the sealing device and the housing can thus be provided by means of said weld seam. A combination of an interference fit and, for example, an adjoining weld is also conceivable for fixing the sealing device in the cavity.

Drawings

The invention is explained in detail below with reference to embodiments shown in the schematic drawings of the figures. The figures show:

fig. 1 is a schematic block diagram of a device 1 for determining pressure according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of an apparatus 100 for determining pressure according to another embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of an apparatus 100 for determining pressure according to another embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of an apparatus 300 for determining pressure according to another embodiment of the present invention;

FIG. 5 is a schematic cross-sectional view of an apparatus 400 for determining pressure according to another embodiment of the present invention;

FIG. 6 is a schematic detail view of the sensor device 120 of the device 100 in FIG. 2;

fig. 7a) to 7c) various possible sensor devices 120 of the device according to the invention; 320, a first step of mixing; 520; and

fig. 8 is a schematic flow diagram for explaining the method according to the invention for producing a device for determining a pressure.

Throughout the drawings, identical or functionally identical elements and devices are provided with the same reference numerals, as long as no further description is given. The numbering of the method steps is merely for the sake of clarity and should not particularly indicate a definite temporal order if no further explanation is given. In particular, several method steps can also be carried out simultaneously.

Detailed Description

Fig. 1 shows a schematic block diagram of a device 1 for determining a pressure according to an embodiment of the invention.

The device 1 has a housing 10 with a cavity 12 having a mouth 13 which leads outwardly from the cavity 12 onto the outside of the housing 10. The housing 10 also has a first sealing structure 14. The device 1 further comprises a sensor device 20 with a second sealing structure 24. The second sealing structure 24 is in engagement with the first sealing structure 14 in such a way that the mouth 13 of the cavity 12 can be closed or already closed by the sensor device 20 by means of the first sealing structure 14 and the second sealing structure 24.

The cavity is pressurized with the pressure to be determined in that a fluid pressurized with the pressure to be determined is introduced into the cavity or has been introduced into the cavity, and the sensor device 20 is designed for determining the pressure to be determined.

The device 1 also has a sealing device 50 which is arranged completely in the cavity 12 and which is configured for pressing the second sealing structure 24 onto the first sealing structure 14 in engagement with the second sealing structure 24 by applying a pressing force to the sensor device 20.

The sensor device 20, the sealing device 50 and the housing 10 are preferably elements that are manufactured separately from one another, i.e. none of two of the three elements are manufactured integrally with one another.

Fig. 2 shows a schematic block diagram of an apparatus 100 for determining pressure according to another embodiment of the present invention.

The device 100 is a variant of the device 1. Sensor device 120 of device 100 has a diaphragm 122, which is part of an integral base 123 of sensor device 120. The base 123 is preferably made of steel. The diaphragm 122 can be formed, for example, by drilling the base 123, so that a section that is thinner than the rest of the base 123 is formed as the diaphragm 122. On a first outer surface of the membrane 122 facing away from the cavity 12, the measurement unit 60 is configured for determining the pressure based on a deformation of the membrane 122. The measurement unit 60 of the device 100 is described in detail below with reference to fig. 6.

The base body 123 of the sensor device 120 is rotationally symmetrical with respect to a rotational symmetry axis R1, which intersects the diaphragm 122, in particular is perpendicular to the diaphragm 122. When in the following axial, tangential or radial directions are mentioned, these are always to be understood as being defined with reference to the axis of rotational symmetry R1.

The base body 123 also has a first internal taper 124, i.e. a tapered section of the base body 123 facing the outer surface of the housing 110, as a second sealing structure, wherein the first internal taper 124 widens increasingly in the radial direction as it becomes further away from the diaphragm 122 in the axial direction. The housing 110 of the device 100 has, as a first sealing structure, a first external cone 114 facing the cavity 12 and being rotationally symmetrical about a rotational symmetry axis R1. The first internal taper 124 forms a fit with the first external taper 114 in such a way that a movement of the base body 123 in the first direction D1 and thus of the sensor device 20 in the first direction D1, which is parallel to the rotational axis of symmetry R1 and faces away from the cavity 12, is positively hindered, so that the first port 13 of the cavity 12 can be closed by the first and

second sealing structures

114, 124 in mutual engagement. The first port 13 is closed by the sensor device 120, in particular when the second sealing structure 124 is pressed against the first sealing structure 114 as a result of the pressure of the loading cavity 12. In a second direction D2, opposite to the first direction D1, the cavity 12 has a second mouth 115 through which the cavity 12 can be loaded with the pressure to be determined.

The base body 123 of the sensor device 120 has a third sealing structure, which is configured as a second external cone 126, which is coaxial to the rotational symmetry axis R1 and to the first internal cone 124 and is formed radially inside the first internal cone 124.

The sealing device 150 is arranged in the cavity 12, and in the device 100, it is pressed into the cavity 12 under pretensioning force in such a way that the sealing device 150 is thereby fixed relative to the housing 110. The sealing device 150 is rotationally symmetrical about a rotational symmetry axis R1 and has a through-opening 155 which establishes a fluid connection between the second mouth 115 of the cavity 12 and the diaphragm 122 on the outer side of the diaphragm 122 facing away from the measuring cell 60.

The sealing device 150 has, as a fourth sealing structure, a second internal taper 154, the second internal taper 154 being configured to be rotationally symmetrical about a rotational symmetry axis R1 and being penetrated by the through portion 155. The second internal taper 154 is designed such that it can form a form-fitting connection with the second external taper 126. Furthermore, the sealing device 150 is pressed into the cavity 12 with a pretension, which is selected and the sealing device 150 is introduced into the cavity 12 in such a way that the second internal taper 154 is pressed onto the second external taper 126, so that a pressure-tight connection is formed. The through-flow connection between the second mouth 115 and the first and

second sealing structure

114, 124, which are associated with one another, is thus closed in particular.

On the outside facing away from the cavity 12, the housing 110 has an internal thread 117, by means of which the housing 110 can be screwed as a pressure nipple, for example, into an injection system, for example, a fuel injection system of a vehicle. At the end of the housing 110 facing away from the diaphragm 122 in the axial direction (which is also referred to as the pressure-side end), a sealing edge 116 of the housing is formed, by means of which sealing edge 116 a pressure-tight connection can be established when the housing 110 is installed in the system. A cover 118 can be provided on the end of the housing 110 in the axial direction at the membrane 122, through which the measuring unit 60 can be contacted. On the side of the cover 118 facing away from the housing 110, a circuit board 119 can be arranged, by means of which the data signals of the measuring unit 60 can be evaluated and/or transmitted.

Fig. 3 shows a schematic cross-sectional view of a device 200 for determining a pressure according to another embodiment of the present invention. The device 200 is a variant of the device 100 according to fig. 2, which differs from the device 100 in that the sealing device 250 of the device 200 is not fixed to the housing 110 by means of an interference fit, but by means of a weld 265. The weld seam 265 in particular surrounds the seal 250 tangentially, i.e. rotationally symmetrically with respect to the rotational symmetry axis R1. Likewise, in the device 200, the sealing device 250 exerts a pressing force on the sensor device 120 on the basis of the pretension.

Fig. 4 shows a schematic cross-sectional view of an apparatus 300 for determining a pressure according to another embodiment of the present invention. The device 300 is a variant of the device 100 according to fig. 2, which differs from the device 100 in the configuration of the sensor device 320 and the sealing device 350.

In the arrangement 300, instead of the second external taper 126 as a third sealing structure, the sensor arrangement 320 has, as a third sealing structure, a sealing edge 326 which is directed toward the second mouth 115 and toward the sealing arrangement 350 and is configured rotationally symmetrically about the rotational symmetry axis R1. The sealing device 350 of the arrangement 300 does not have a fourth sealing structure, but rather a flat outer side 351 is formed axially on the end of the sealing device 350 facing the sensor device 320, so that the sealing edge 326 together with the flat outer side 351 of the sealing device 350 establishes a pressure-tight connection on the basis of the pressing force exerted by the sealing device 350 on the sensor device 320.

Fig. 5 shows a schematic cross-sectional view of an apparatus 400 for determining a pressure according to another embodiment of the present invention. The device 400 is a variant of the device 300 according to fig. 4, which differs from the device 300 by the configuration of the sealing device 450.

In the arrangement 400, a blind hole 457 which is rotationally symmetrical with respect to the rotational symmetry axis R1 and in which a sealing ring 458 is inserted is formed in the outer side 351 of the sealing arrangement 450 facing the sensor arrangement 320. The sealing edge 326 of the sensor device 320 is brought into pressure-tight engagement with the sealing ring 458 on the basis of a pretensioning force, i.e. on the basis of a pressing force exerted on the sensor device 320 by the sealing device 450.

A further sealing edge 454 is formed on the sealing device 450, which engages in a pressure-tight manner with a sealing ring 458. The further sealing edge 454 is preferably formed on the surface of the blind hole 457 of the sealing arrangement 450 facing the sensor arrangement 320, the axis of rotational symmetry R1 being perpendicular to this surface.

The sealing ring 458 is rotationally symmetrical about a rotational symmetry axis R1 and is preferably metallic and deformable by the sealing edges 326, 454.

Fig. 6 shows a schematic detail view of the sensor device 120 of the device 100 in fig. 2. Fig. 6 shows a schematic top view of the sensor device 120 in the second direction D2 on the left side and a cross-sectional view of a part of the sensor device 120 on the right side.

On an outer side 61 of the sensor device 120 facing away from the housing 110, a measuring unit 60 is arranged, which is configured as a thin-film structure according to fig. 6. The thin-film structure has or consists of an insulating layer 62 (for example silicon oxide) and a functional layer 64. All piezoresistive materials can be used as the functional layer 64, such as nickel-chromium alloy, platinum, polysilicon, titanium oxynitride, etc.

In the functional layer 64, for example during the production method according to the invention, at least four resistors 610 are structured, for example by wet etching, dry etching, laser removal or the like. The resistor 610 is connected as a wheatstone bridge and has a loop-shaped area 612, so that the resistance value of the resistor 610 changes due to the deformation, in particular the elongation, of the membrane 122. The supply lines to the wheatstone bridge and the contact surfaces can be implemented in the plane of the functional layer 64 or in an additional metallization plane. Additionally, the functional layer may be protected by a passivation layer (e.g. silicon nitride) or other means (e.g. gel coating).

The circuit board 119 can have an evaluation circuit, by means of which the voltage across the wheatstone bridge can be evaluated and an output signal proportional to the pressure to be determined can be provided on the basis thereof, for example in the form of a voltage from zero to five volts or in the form of a current from four to twenty milliamps, for example, or in digital form. The output signal can be intercepted on the circuit board and sent out, for example, by means of a suitable plug, which forms an upper part of the cover 118.

Fig. 7a) to 7c) show schematic cross-sectional views of various

possible sensor devices

120, 320, 520 of the device according to the invention. Fig. 7a) shows the base body 123 of the sensor device 122 from fig. 2 and 3. Fig. 7b) shows a base body 323 of the sensor device 320 from fig. 4 and 5. Fig. 7c) shows a further possible form of a base body 523 of the sensor device 520, which has a shoulder 524 as a second sealing structure, which is pressed against a corresponding plate of the housing by the sealing device.

Fig. 8 shows a schematic flow diagram for explaining the method according to the invention for producing a device for determining a pressure. The manufacturing method is particularly suitable for manufacturing the device 1; 100, respectively; 200 of a carrier; 300, respectively; 400, and a part of the content has already been explained in detail with reference to fig. 1 to 7 c). The manufacturing method can be adapted in particular to all variants and modifications described with reference to the device according to the invention.

In step S01, a structure having a cavity 12 and a first seal structure 14 is constructed; 114 of the housing 10; 110. in step S02, the second seal structure 24 is configured; 124; 524 of the sensor device 20; 120 of a solvent; 320, a first step of mixing; 520. in step S03, the sensor device 20 configured accordingly; 120 of a solvent; 320, a first step of mixing; 520 into the cavity 12, so that the mouth 13 of the cavity 12 passes through the sensor device 20; 120 of a solvent; 320, a first step of mixing; 520 may be closed or enclosed. In step S04, the sealing device 50; 150; 250 of (a); 350 of (a); 450 are at least partially disposed in the cavity 12 such that the sealing device 50; 150; 250 of (a); 350 of (a); 450 by applying a squeezing force to the sensor device 20; 120 of a solvent; 320, a first step of mixing; 520 to position the second seal structure 24; 124; 524 to the first seal structure 14; 114, i.e. to improve their tightness.

A sealing device 50; 150; 250 of (a); 350 of (a); 450 can be pressed into the cavity 12 in such a way that the sealing device 50; 150; 250 of (a); 350 of (a); 450 and at least sensor device 20; 120 of a solvent; 320, a first step of mixing; 520 there is a pre-load force. A sealing device 50; 150; 250 of (a); 350 of (a); 450 can be engaged into the cavity 12 under a predetermined pretension and fixed to the housing 10 by means of a weld 256; 110.

Although the present invention has been described above with reference to the preferred embodiments, it is not limited thereto but can be modified in various ways. The invention is particularly susceptible of being varied or modified in various ways without thereby departing from the core of the invention.

Claims

1. Device (1; 100; 200; 300; 400) for determining a pressure, comprising:

a housing (10; 110) having a cavity (12) and a first sealing structure (14; 114);

a sensor device (20; 120; 320; 520) having a second sealing structure (24; 124; 524), which is adapted to the first sealing structure (14; 114) in such a way that a mouth (13) of the cavity (12) can be closed by the sensor device (20; 120; 320) by means of the first sealing structure (14; 114) and the second sealing structure (24; 124; 524), wherein the cavity (12) is charged with a pressure to be determined, the sensor device (20; 120; 320; 520) being configured for determining the pressure to be determined; and

a sealing device (50; 150; 250; 350; 450) which is arranged at least partially in the cavity (12) and which is configured for pressing the second sealing structure (24; 124; 524) onto the first sealing structure (14; 114) by applying a pressing force to the sensor device (20; 120; 320; 520).

2. The apparatus of claim 1, wherein the first and second electrodes are disposed on opposite sides of the housing,

characterized in that the sensor device (120; 320; 520) has:

a membrane (122) in connection with the cavity (12); and

a measuring unit (60) configured for determining the pressure to be determined, at which the cavity (12) is loaded, on the basis of a deformation of the diaphragm (122).

3. The apparatus of claim 1 or 2,

characterized in that the sealing device (150; 250; 350; 450) is mounted on the housing (110) under a pretensioning force, so that the sealing device (150; 250; 350; 450) is pressed against the sensor device (20; 120; 320) on the basis of the pretensioning force, so that the second sealing structure (24; 124; 524) is pressed against the first sealing structure (14; 114).

4. The apparatus of claim 1 or 2,

characterized in that the sealing device (250) is fixed to the housing (110) by means of at least one weld seam (256).

5. The apparatus of claim 1 or 2,

characterized in that the first sealing structure (114) has a first external cone and the second sealing structure (124) has a first internal cone, wherein the first internal cone can be pressed onto the first external cone in a form-fitting manner in order to close the mouth (13).

6. The apparatus of claim 1 or 2,

characterized in that a third sealing structure of the sensor device (120; 320) is designed for sealing action together with the sealing device (150; 250; 350; 450), said third sealing structure having an external cone (126) and/or a sealing edge (326).

7. The apparatus of claim 6, wherein the first and second electrodes are disposed on opposite sides of the substrate,

characterized in that the third sealing structure of the sensor device (120) has a second external cone portion (126), while the sealing device (150; 250) has a fourth sealing structure configured as a second internal cone portion (154), which fourth sealing structure can form a fit with the second external cone portion (126).

8. Method for manufacturing a device for determining a pressure, comprising the steps of:

(S01) constructing a housing (10; 110) having a cavity (12) and a first seal structure (14; 114);

(S02) constructing a sensor device (20; 120; 320) having a second sealing structure (24; 124);

(S03) introducing the sensor device (20; 120; 320; 520) into the cavity (12) in such a way that the mouth (13) of the cavity can be closed by the sensor device (20; 120; 320; 520); and

(S04) arranging a sealing arrangement (50; 150; 250; 350; 450) at least partially in the cavity (12) such that the sealing arrangement (50; 150; 250; 350; 450) presses the second sealing structure (24; 124; 524) against the first sealing structure (14; 114) by applying a pressing force to the sensor arrangement (20; 120; 320).

9. The method of claim 8, wherein the first and second light sources are selected from the group consisting of,

characterized in that, when the sealing device (50; 150; 250; 350; 450) is arranged (S04) in the cavity (12), the sealing device (50; 150; 250; 350; 450) is pressed into the cavity (12) in such a way that a preload is present between the sealing device (50; 150; 250; 350; 450) and at least the sensor device (20; 120; 320) in order to fix the sealing device (50; 150; 250; 350; 450) in the cavity (12) and in order to apply the pressing force to the sensor device (20; 120; 320).

10. The method according to claim 8 or 9,

characterized in that, when the sealing device (250) is arranged in the cavity (12) (S04), the sealing device (250) is engaged in the cavity (12) under a predetermined prestress and is fixed to the housing (10; 110) by means of a weld seam (256) in order to fix the sealing device (250) in the cavity (12) and in order to apply the pressing force to the sensor device (20; 120; 320).