Sensor housing

Abstract

The present invention relates to a sensor housing, comprising: - a sensor body having at least one main holder disposed therein; - a sensor cover having at least one auxiliary holder adapted to be disposed on the sensor body such that the main holder and the auxiliary holder are enclosed within the sensor body; - a locking unit having at least one locking element for releasably connecting the main holder and the auxiliary holder, wherein the locking element comprises a magnetizable or magnetic material and is mounted to be movable between a locked position and a released position such that the locking element can be moved between the locked position and the released position by an applied magnetic field, wherein in the locked position the locking element locks the main holder (21) and the auxiliary holder (31), and in the released position the locking element does not lock the main holder and the auxiliary holder.

Description

TECHNICAL FIELD

[0001] The present invention relates to a sensor housing. BACKGROUND

[0002] Sensors are used in process automation technology in many application areas. In most applications, the sensor is in direct contact with the medium to be measured. Sensors for turbidity, oxygen, fluorescence or spectroscopic measurements, such as ultrasonic sensors or optical sensors, have a sensor housing for protecting sensitive sensor components from the medium to be measured or other environmental influences. However, in order to be able to guarantee the best possible measurement quality, the sensor must be regularly maintained. For this purpose, it can be necessary to ensure access to the sensitive sensor components arranged in the sensor housing.

[0003] For this reason, two-part sensor housings are often used, which allow the sensor housing to be opened and closed again. Since the sensor housing is in contact with the medium to be measured, it must be ensured that the two-part sensor housing does not open itself during operation as a result of environmental influences, for example vibrations or impacts.

[0004] In order to prevent accidental opening of the two-part sensor housing, the two parts of the sensor housing are usually adhesively bonded to one another. However, the disadvantage of adhesive bonding is that the sensor housing can only be opened with difficulty at the next maintenance and that the sensor housing can be damaged during opening. Furthermore, the sensitive sensor components can be damaged by the gases released by the adhesive. SUMMARY

[0005] It is therefore an object of the present invention to provide a sensor housing which can be easily opened and at the same time prevents accidental opening of the sensor housing.

[0006] According to the invention, this object is achieved by a sensor housing according to claim 1.

[0007] The sensor housing according to the invention comprises:

[0008] - a sensor body having at least one primary holder arranged in the sensor body,

[0009] - a sensor cover having at least one secondary holder,

[0010] - a locking unit having at least one locking element for releasably connecting the main holder and the auxiliary holder. The sensor cover is adapted to be arranged on the sensor body such that the main holder and the auxiliary holder are enclosed in the sensor body. The locking element comprises a magnetizable or magnetic material and is mounted so as to be movable between a locking position and a release position such that the locking element can be moved between the locking position and the release position by an applied magnetic field, wherein in the locking position the locking element locks the main holder with the auxiliary holder and in the release position the locking element does not lock the main holder with the auxiliary holder.

[0011] The sensor housing according to the present application makes it possible to remove the sensor cover from the sensor body without having to exert a great deal of force. This prevents the sensor housing from being inadvertently damaged when the sensor cover is removed. At the same time, the locking unit ensures that the sensor housing is effectively protected against accidental opening, for example against accidental opening during sensor operation. Thus, a leakproof and reliable sensor housing is provided.

[0012] According to one embodiment of the present application, the locking unit comprises a securing element which is adapted to move the locking element from the release position into the locking position and / or to hold it in the locking position.

[0013] According to a further embodiment of the present application, the securing element comprises a spring element or a permanent magnet.

[0014] According to one embodiment of the present application, the sensor housing further has an internal magnetic field source and a control unit. The internal magnetic field source comprises an electrical coil which is connected to the control unit. The electrical coil is adapted to be controlled by the control unit such that a magnetic field is generated which covers the locking element in order to move the locking element into the release position.

[0015] According to one embodiment of the present application, the locking element comprises a permanent magnet.

[0016] According to one embodiment of the present application, the locking element has a ring-shaped spring element which is adapted to move the locking element from the release position into the locking position and / or to hold it in the locking position.

[0017] According to one embodiment of the present application, the locking element has two opposite permanent magnets which are fastened to the ring-shaped spring element.

[0018] According to one embodiment of the present application, the sensor body has a first thread and the sensor cover has a second thread which is complementary to the first thread, or the sensor body has a first bayonet closure part and the sensor cover has a second bayonet closure part which is complementary to the first bayonet closure part.

[0019] According to one embodiment of the application, a recognition feature is applied to the outside of the sensor housing in order to indicate the position of the locking element in the sensor housing.

[0020] The above object is also achieved by a sensor housing module according to claim 10.

[0021] The sensor housing module according to the application has a sensor housing according to the application and an external magnetic field source. The external magnetic field source comprises a permanent magnet or an electric coil. BRIEF DESCRIPTION OF DRAWINGS

[0022] The application is explained in more detail based on the following description in conjunction with the drawings. Shown are:

[0023] Figure 1 A cross-sectional view of a sensor housing according to the application is shown, which has a first embodiment of a locking unit,

[0024] Figure 2 A cross-sectional view of a sensor housing according to the application is shown, which has a first embodiment of a locking unit, Figure 1 The sensor housing shown, with an alternative locking unit in its released position,

[0025] Figure 3 A side view of a sensor housing according to the application is shown, in which an alternative locking unit in its locked position is visible,

[0026] Figure 4 A cross-sectional view of a sensor housing according to the application is shown, which has a first embodiment of a locking unit, Figure 3 The sensor housing shown, with an alternative locking unit in its released position,

[0027] Figure 5 A side view of a sensor housing according to the application is shown, in which an alternative locking unit in its locked position is visible,

[0028] Figure 6 A cross-sectional view of a sensor housing according to the application is shown, which has a first embodiment of a locking unit, Figure 5 The sensor housing shown, with an alternative locking unit in its released position,

[0029] Figure 7 An alternative embodiment of a sensor housing is shown, which has an internal magnetic field source,

[0030] Figure 8 An embodiment of a sensor cover is shown, which has a bayonet closure,

[0031] Figure 9 A side view of a sensor cover according to the application is shown, in which an alternative locking unit in its locked position is visible, Figure 7 The sensor cover shown, with an alternative locking unit in its released position,

[0032] Figure 10 A cross-sectional view of a sensor housing according to the application is shown, which has a first embodiment of a locking unit, Figure 7sensor cover, with a magnetic field source and a locking element in its released position,

[0033] Figure 11 a cross-sectional view of a further embodiment of a sensor housing, with a further embodiment of a locking unit is shown,

[0034] Figure 12 a cross-sectional view of a sensor housing is shown, Figure 10

[0035] Figure 13 a cross-sectional view of a sensor housing is shown, Figure 10

[0036] Figure 14 a cross-sectional view of a sensor housing is shown,

[0037] Figure 15 a cross-sectional view of a sensor housing is shown, Figure 13 DETAILED DESCRIPTION

[0038] Figure 1 A sensor housing 1 is shown, which has a sensor body 20, a sensor cover 30 and a locking unit 40. The sensor housing 1 is suitable for accommodating sensitive sensor components, for example optical emitters / detectors or ultrasound generators / detectors or printed circuit boards with sensitive electronic components. Preferably, a sealing ring, for example an O-ring, can also be fitted between the sensor body 20 and the sensor cover 30.

[0039] The sensor body 20 has at least one main holder 21, which is arranged in the sensor body 20. The main holder 21 is for example a hole, a recess, a groove or a similar cavity in the sensor body 20. In addition, the sensor body 20 can have a first thread 22 (see Figure 1 ). In an alternative embodiment, the sensor body 20 has a first bayonet closure part 23 (see Figure 9 ). The sensor body 20 has for example a cylindrical shape and extends along an extension axis X.

[0040] ​​​The sensor cover 30 has at least one secondary holder 31. The secondary holder 31 is for example a hole, a recess, a groove or a similar cavity in the sensor cover 30. The sensor cover 30 is adapted to be arranged on the sensor body 20 such that the primary holder 21 and the secondary holder 31 are enclosed in the sensor body 20. Furthermore, the sensor cover 30 can have a second thread 32 (see Figure 1 ) complementary to the first thread 22 of the sensor body 20 in order to form a threaded closure. In an alternative embodiment, the sensor cover 30 has a second bayonet closure part 33 (see Figure 8 ) complementary to the first bayonet closure part 23 in order to form a bayonet closure. The sensor cover 30 has for example a cylindrical shape and extends along the extension axis X.

[0041] The locking unit 40 comprises at least one locking element 41. The locking element 41 is adapted to connect the primary holder 21 and the secondary holder 31 such that the sensor cover 30 cannot be removed from the sensor body 20. The locking element 41 contains a magnetizable or magnetic material. The locking element 41 can be mounted in the primary holder 21 and the secondary holder 31. The locking element 41 is mounted such that it is movable between a locking position in which the locking element 41 locks the primary holder 21 with the secondary holder 31 and a release position in which the locking element 41 releases the primary holder 21. Because the locking element 41 contains a magnetizable or magnetic material, the locking element 41 is adapted to be moved between the locking position and the release position by an applied magnetic field. The locking element 41 is for example a magnetizable metal pin (see Figure 1 、 Figure 2 and Figure 7 ), a magnetic element (see Figures 3 to 6 and Figures 8 to 10 ) or a ring with a magnetic element (see Figures 11 to 15 ). Other embodiments of the locking element 41 are possible as long as they are compatible with the technical teaching of the present invention.

[0042] In Figure 1 , the locking element 41 is a magnetizable metal pin extending parallel to the extension axis X. In this embodiment, the locking element 41 is movable parallel to the extension axis X between its locking position and its release position. In the embodiment shown in Figure 1 , the sensor housing 1 has to be mounted or used in such a way that the locking element 41 is moved by a first force Fl, in this case the force of gravity, into its locking position.

[0043] Figure 2 A modified embodiment of the sensor housing 1 shown in Figure 1 is shown. As Figure 2As can be seen, the locking unit 40 may also have a fixing element 42, which is adapted to move the locking element 41 from the released position to the locked position and / or hold it in the locked position. The force generated by the fixing element 42 in Figure 1 , Figure 3 , Figure 5 , Figure 8 , Figure 12 and Figure 14 The diagram is schematically illustrated by thin arrows (or two such arrows) extending in the direction of the force. Therefore, the sensor housing 1 is always locked under normal conditions, i.e., unaffected by external or internal magnetic fields. For this embodiment, the sensor housing 1 can therefore be mounted or used in any orientation independent of the direction of gravity. Figures 1 to 4 In the illustrated embodiment, the fixing element 42 includes a permanent magnet. However, it can also be designed as a spring element (see...). Figures 5 to 15 ).

[0044] When the fixing element 42 is designed as a permanent magnet, it is arranged within the sensor cover 30 such that the locking element 41 is exposed to the magnetic field of the permanent magnet in both its locked and released positions. Therefore, a first force F1, induced by the magnetic field of the fixing element 42 and suitable for moving the locking element 41 to the locked position, is always applied to the locking element 41. The first force F1 generated by the magnetic field of the fixing element 42 is greater than the frictional resistance acting on the locking element 41 during its movement. The frictional resistance depends on the material properties and geometry of the locking element 41; therefore, it is preferable to select the permanent magnet of the fixing element 42 based on these parameters.

[0045] Figure 2 The locking element 41 is shown in the released position. In order to... Figure 2 The embodiments shown and others Figure 1 The locking element 41 in the illustrated embodiment moves to the released position, as shown. Figure 2 As can be seen, the locking unit 40 is exposed to the external magnetic field source 2. In this case, the external magnetic field source 2 can be arranged externally relative to the sensor housing 1, that is, outside the sensor housing 1. The sensor housing 1 and the external magnetic field source 2 form the sensor housing module 10. The second force F2 is applied to the locking element 41 by the magnetic field of the external magnetic field source 2. Figure 2 , Figure 4 , Figure 6 , Figure 7 , Figure 10 , Figure 11 , Figure 13 and Figure 15The second force F2 exerted by the magnetic field of the external magnetic field source 2 on the locking element 41 is greater than the first force Fl exerted by the fixing element 42 and / or the gravitational force, which is symbolically shown by the thickness of the arrows.

[0046] Figure 2 The external magnetic field source 2 is schematically shown as a permanent magnet. Of course, the external magnetic field source 2 can also be, for example, an electric coil suitable for generating a magnetic field. All permanent magnets shown in the figures have a N-pole denoted with "+" and a S-pole denoted with "-".

[0047] Figure 3 The locking element 41 is shown in its locked position. The fixing element 42 exerts a first force Fl on the locking element 41. In Figure 3 In the embodiment shown, the locking unit 40 is arranged horizontally. Therefore, the external magnetic field source 2 for moving the locking element 41 should be arranged radially with respect to the extension axis X of the sensor housing 1 in order to move the locking element 41 into its release position. In order to simply detect the position at which the magnetic field should be applied to the sensor housing 1 or the locking unit 40 arranged in the sensor housing 1 in order to open the sensor housing 1, an identification feature (for example, a marking, a symbol or a text) can be applied to the outside of the sensor housing 1. Said identification feature allows the user to position the locking element 41 in the sensor housing 1. This makes it possible for the external magnetic field source 2 (for example, a permanent magnet or an electric coil) to optimally apply the magnetic field generated by the external magnetic field source 2 to the locking element 41, i.e. for the second force F2 generated by the magnetic field of the external magnetic field source 2 to optimally act on the locking element 41.

[0048] Figure 4 The locking element 41 is shown in its release position. By means of its magnetic field, the external magnetic field source 2 exerts a second force F2 on the locking element 41, which forces the locking element 41 into its release position, so that the sensor cover 30 can be removed.

[0049] In Figure 5 The fixing element 42 is an elastic spring, which presses the locking element 41 into the locked position with a first force Fl.

[0050] Figure 6 It is shown how the external magnetic field source 2 presses the locking element 41 into the release position by means of its magnetic field. The second force F2 of the magnetic field of the external magnetic field source 2 is greater than the first force Fl of the elastic spring.

[0051] Figure 7An alternative embodiment is shown in which the internal magnetic field source 2' is arranged within the sensor housing 1. In this variation, the internal magnetic field source 2' is designed as an electric coil. The electric coil is connected to a control unit 3 for control by the control unit 3. As in Figure 5 As in the illustrated embodiment, the locking element 41 is pressed into its locked position by the fixing element 42 (spring element). Therefore, when the coil is not energized, the locking element 41 is in its locked position. If the locking element 41 is to be moved to its released position, the coil is activated to generate a magnetic field. The magnetic field of the coil causes the locking element 41 to be located within the magnetic field of the coil when in its locked position, thus a second force F2 acts on the locking element 41. Here, the magnetic field is also chosen such that the second force F2 is greater than the first force F1 generated by the fixing element 42. An advantage of this embodiment is that the sensor housing 1 can therefore be easily opened by activating the internal magnetic field source 2'. Figure 7 For simplicity, the internal magnetic field source 2' is drawn next to the locking unit 40, but it can also be arranged, for example, such that the locking unit 40 or a portion thereof is enclosed by the internal magnetic field source 2' (i.e., the coil).

[0052] Of course, as long as it is technically possible, Figure 7 The illustrated embodiments can also be combined with other embodiments described herein. For example, the locking element 41 can be moved to its released position by an internal magnetic field source 2' or an external magnetic field source 2.

[0053] Figure 8 A sensor cover 30 with a second bayonet closure component 33 is shown.

[0054] Figure 9 A view of the sensor cover 30 from below is shown, i.e., along the extending axis X of the sensor housing 1. The locking unit 40, arranged within the sensor cover 30, is shown as visible. In this embodiment, the retaining element 42 is radially movable relative to the extending axis X, i.e., applying a first force F1 radially relative to the extending axis X on the locking element 41. The locking element 41 is fastened (e.g., adhesively bonded) to the retaining element 42.

[0055] Figure 9 The illustrated embodiments are particularly suitable for variations of the sensor housing 1, which have threaded connections or bayonet closures for connecting the sensor body 20 and the sensor cover 30. In the locked position, the locking element 41 thus prevents or restricts rotational movement of the sensor cover 30 relative to the sensor body 20.

[0056] Figure 10The locking element 41 is shown in its release position. The second force F2 resulting from the magnetic field of the magnetic field source 2 is indicated by the arrow and moves the locking element 41 out of the locking position and into the release position.

[0057] Figure 11 A partial cross-sectional view of another embodiment of the sensor housing 1 is shown. The fixing element 42 of the locking unit 40 has here a ring design and extends around the extension axis X. In this embodiment, the locking unit 40 is mounted in an auxiliary holder 31 (here for example a recess) of the sensor body 20 and is adapted to engage in a main holder 21 (here for example a groove) of the sensor cover 30.

[0058] Figure 12 A partial cross-sectional view of another embodiment of the sensor housing 1 is shown. The fixing element 42 of the locking unit 40 has here a ring design and extends around the extension axis X. In this embodiment, the locking unit 40 is mounted in an auxiliary holder 31 (here for example a recess) of the sensor body 20 and is adapted to engage in a main holder 21 (here for example a groove) of the sensor cover 30. Figure 11 The locking unit 40 shown has a locking element 41 and a fixing element 42 in its locking position. The locking element 41 is fastened (for example adhesively bonded or fixed in another known fastening manner) to the fixing element 42. Here, the shape (for example oval) of the fixing element 42 is such that the fixing element has a pretension when arranged in the sensor housing 1. The pretension of the fixing element 42 generates a first force Fl that presses the locking element 41 and / or the fixing element 42 into the main holder 21 (here a groove) of the sensor body 20. When the sensor cover 30 is arranged in the sensor body 20, the locking element 41 and / or the fixing element 42 thus engage in the groove 21 of the sensor body 20. In this embodiment, the fixing element 42 is for example made of metal or plastic.

[0059] Figure 13 The locking element 41 is shown in its release position. The magnetic field of the magnetic field source 2 generates a second force F2 (which is greater than the first force Fl generated by the fixing element 42) that deforms the fixing element 42; for example, forces the fixing element 42 from its oval shape into a circular shape, so that the fixing element 42 no longer engages in the groove 21 of the sensor cover 30.

[0060] As Figures 11 to 13 The locking unit 40 is shown as preferably having two locking elements 41 that are fastened to the ring-shaped fixing element 42 opposite one another. In order to move the locking elements 41 into their release position, in this embodiment the two locking elements 41 should be subjected to the magnetic field simultaneously.

[0061] Figure 14One alternative embodiment of the securing element 42 is shown. Here, the locking element 41 is also fastened (for example, adhesively bonded) to the securing element 42. In this exemplary embodiment, the securing element 42 is a clamping ring which, when inserted into the sensor housing 1, has a pretension due to its shape. The clamping ring extends around the extension axis X. The clamping ring is seated in the auxiliary holder 31, for example in a recess in the sensor cover 30. The locking element 41 is designed such that only a portion of the locking element 41 engages in the main holder 21 (here also a groove or recess) of the sensor body 20. This portion, which engages in the groove or recess, has a greater radius with respect to the extension axis X compared to the remainder of the securing element 42, for example.

[0062] Figure 15 The locking element 41 in its released position is shown. The second force F2, which is generated by the magnetic field of the magnetic field source 2, moves the locking element 41 (again a permanent magnet) in order to pull the clamping ring out of the groove. As Figures 11 to 13 As described in the embodiment of the clamping ring is deformed here also due to the second force F2.

[0063] List of reference signs

[0064] 1 sensor housing

[0065] 2 magnetic field source

[0066] 3 control unit

[0067] 10 sensor housing module

[0068] 20 sensor body

[0069] 21 main holder

[0070] 22 first thread

[0071] 23 first bayonet closure part

[0072] 30 sensor cover

[0073] 31 auxiliary holder

[0074] 32 second thread

[0075] 33 second bayonet closure part

[0076] 40 locking unit

[0077] 41 locking element

[0078] 42 securing element

[0079] F1 first force

[0080] F2 second force

[0081] X-axis extension.

Claims

1. A sensor housing (1) comprising: - a sensor body (20) having at least one primary holder (21) arranged in the sensor body (20), - a sensor cover (30) having at least one secondary holder (31), the sensor cover (30) being adapted to be arranged on the sensor body (20) such that the primary holder (21) and the secondary holder (31) are enclosed in the sensor body (20), - a locking unit (40) having at least one locking element (41) for releasably mechanically connecting the primary holder (21) of the sensor body (20) and the secondary holder (31) of the sensor cover (30) using the locking element (41), wherein the locking element (41) comprises a magnetizable material and the locking element (41) is mounted movable between a locking position and a release position, such that the locking element (41) is movable between the locking position and the release position by an applied external magnetic field from an external magnetic field source (2), wherein in the locking position the locking element (41) mechanically locks the primary holder (21) of the sensor body (20) and the secondary holder (31) of the sensor cover (30) and in the release position the locking element (41) does not mechanically lock the primary holder (21) of the sensor body (20) and the secondary holder (31) of the sensor cover (30).

2. The sensor housing (1) according to claim 1, wherein the locking unit (40) comprises a fixation element (42) adapted to move the locking element (41) from the release position into the locking position and / or to hold the locking element (41) in the locking position.

3. The sensor housing (1) according to claim 2, wherein the fixation element (42) comprises a spring element or a permanent magnet.

4. The sensor housing (1) according to claim 3, wherein the sensor housing (1) further has an internal magnetic field source (2') and a control unit (3), wherein the internal magnetic field source (2') comprises an electric coil connected to the control unit (3), wherein the electric coil is adapted to be controlled by the control unit (3) such that a magnetic field is generated covering the locking element (41) in order to move the locking element (41) into the release position.

5. The sensor housing (1) according to any one of claims 1-4, wherein the locking element (41) comprises a permanent magnet.

6. The sensor housing (1) according to any one of claims 1-4, wherein the locking element (41) has a ring-shaped spring element adapted to move the locking element (41) from the release position into the locking position and / or to hold the locking element (41) in the locking position.

7. The sensor housing (1) according to claim 6, wherein the locking element (41) has two opposite permanent magnets which are fastened to the ring-shaped spring element.

8. The sensor housing (1) according to any one of claims 1-4, wherein the sensor body (20) has a first thread (22) and the sensor cover (30) has a second thread (32) which is complementary to the first thread (22), or the sensor body (20) has a first bayonet closure part (23) and the sensor cover (30) has a second bayonet closure part (33) which is complementary to the first bayonet closure part (23).

9. The sensor housing (1) according to any one of claims 1-4, wherein an identification feature is attached to the outside of the sensor housing (1) in order to indicate the position of the locking element (41) in the sensor housing (1).

10. A sensor housing module (10) having a sensor housing (1) according to any one of claims 1-9 and an external magnetic field source (2), wherein the external magnetic field source (2) comprises a permanent magnet or an electric coil.

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