Cleaning unit for sensors

Abstract

The invention relates to a cleaning unit (10) for a sensor (1), the sensor (1) having a sensor housing (2) and a drive shaft (3), the cleaning unit (10) comprising: a holding element extending along an axis (X1) and being suitable for being mounted on the drive shaft (3) so that the cleaning unit (10) can be moved by the drive shaft (3); a wiper element, which is fastened to the holding element and has a ring axially surrounding the holding element so that when the holding element is mounted on the drive shaft (3), the ring is in contact with the sensor housing (2) of the sensor (1), wherein the ring has at least one tooth extending radially relative to the axis (X1).

Description

Technical Field

[0001] The invention relates to a cleaning unit for a sensor and a sensor having the cleaning unit. Background Art

[0002] In analytical measurement technology, in particular in the field of water management and environmental analysis and in industry (for example in food technology, biotechnology and the pharmaceutical industry), as well as for various laboratory applications, it is of vital importance to have a detailed understanding of the composition or state of the measured medium to be monitored. These measured quantities can be acquired and / or monitored by various sensors, such as optical or acoustic sensors.

[0003] The sensor is arranged in a sensor housing in order to protect the sensor electronics from environmental influences, for example from the measured medium. However, over time the sensor housing may become dirty due to environmental influences. For this reason, the sensor housing, in particular the window of the sensor housing for detecting the sensor, must be cleaned regularly so that the sensor always provides the best measurement results. In most cases, if the sensor housing is not cleaned correctly, for example because the cleaning unit is defective, this has a direct impact on the quality of the sensor measurement results. For example, dirt deposits on the sensor housing may lead to a greater rotational resistance of the cleaning unit and cause defects in the cleaning unit. For this reason, it is important to provide the sensor with a reliable cleaning unit. Summary of the invention

[0004] The object of the present invention is therefore to provide a cleaning unit for a sensor which is robust, reliable and cost-effective.

[0005] The cleaning unit according to the present invention comprises:

[0006] a holding element extending along the axis and suitable for being mounted on the drive shaft so that the cleaning unit can be moved by the drive shaft,

[0007] a wiper element which is fastened to the holding element and has a ring which axially surrounds the holding element so that the ring is in contact with the sensor housing of the sensor when the holding element is mounted on the drive shaft,

[0008] The ring has at least one tooth extending radially relative to the axis.

[0009] The cleaning unit according to the invention makes it possible to avoid dirt deposits in the region of the axis of rotation of the cleaning unit, i.e. around the drive shaft. Thus, the motor connected to the drive shaft located in the interior of the sensor body is prevented from being subjected to unnecessarily high torques, which ultimately leads to a longer service life of the motor and more efficient cleaning of the sensor housing.

[0010] According to one embodiment of the invention, the wiper element further has a lip which extends radially with respect to the axis and is designed to come into contact with the sensor housing when the retaining element is mounted on the drive shaft.

[0011] According to one embodiment of the invention, the ring and the lip are formed in one piece.

[0012] According to one embodiment of the invention, the wiper element is made of rubber.

[0013] According to one embodiment of the invention, the holding element and the wiper element are produced by a multi-component injection molding process.

[0014] According to one embodiment of the invention, the lip is adapted to clean a predetermined area of ​​the sensor housing when the cleaning unit is moved by the drive shaft around the axis at a certain angle, wherein the number of teeth is selected so that the teeth are arranged on the ring so that when the cleaning unit rotates around the angle, the teeth pass in all directions, thereby avoiding deposits between the teeth.

[0015] According to one embodiment of the invention, the teeth have a cleaning surface and the lip has a cleaning surface.The two cleaning surfaces are arranged in a plane.

[0016] According to one embodiment of the invention, the holding element is detachably attached to the drive shaft, for example by means of screws.

[0017] According to one embodiment of the invention, the sensor has a sensor housing and a drive shaft, and the cleaning unit is attached to the drive shaft.

[0018] According to one embodiment of the invention, a sliding element is arranged on the drive shaft between the cleaning unit and the sensor housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is explained in more detail based on the following description of the accompanying drawings. As shown below:

[0020] - Figure 1 shows an exemplary representation of a sensor with a cleaning unit according to the invention;

[0021] - Figure 2 Shows Figure 1 An enlarged cross-sectional view of the cleaning unit shown,

[0022] - Figure 3 Shown from different perspectives Figure 1 Sensor with cleaning unit,

[0023] - Figure 4 Shows Figure 3 An enlarged cross-sectional view of the cleaning unit shown,

[0024] - Figure 5 Shows Figure 1 The wiper element of the cleaning unit shown,

[0025] - Figure 6 Shown from different perspectives Figure 5 The wiper element shown,

[0026] - Figure 7 A view showing a region of the sensor housing to be cleaned by a cleaning unit, wherein the cleaning unit is in a first position,

[0027] - Figure 8 Shows Figure 7 An area is shown in which the cleaning unit is in a position different from the first position. DETAILED DESCRIPTION

[0028] Figure 1 A sensor 1 with a cleaning unit 10 according to the invention is shown. The sensor 1 has a sensor housing 2 and a drive shaft 3. A motor (not shown) for driving the drive shaft 3 is arranged in the sensor housing 2. The motor is, for example, an electric motor and is frictionally connected to the drive shaft 3. For example, the rotor of the electric motor can also serve as the drive shaft 3. The drive shaft 3 extends out of the sensor housing 2 along the axis X1 so that the cleaning unit 10 can be attached to the drive shaft 3.

[0029] Figure 2 An alternative embodiment of a cleaning unit 10 is shown. The cleaning unit 10 comprises a holding element 20 and a wiper element 30.

[0030] The holding element 20 extends along the axis X1 and is suitable for being mounted on the drive shaft 3 so that the cleaning unit 10 can be moved by the drive shaft 3. For example, the holding element 20 can be detachably attached to the drive shaft 3 by means of screws 4 (see Figures 2 to 4 ).

[0031] Of course, other detachable fastening types are also conceivable for attaching the holding element 20 to the drive shaft 3. The advantages of a detachable connection of the holding element 20 or the cleaning unit 10 to the drive shaft 3 are obvious: a worn cleaning unit 10 can thus be replaced quickly and easily without having to replace other components of the sensor 1.

[0032] According to one embodiment, the sliding element 5 is arranged between the cleaning unit 10 and the sensor housing 2 (see Figure 2 and Figure 4). The sliding element 5 surrounds the drive shaft 3. The sliding element 5 is, for example, a washer or another element which reduces the effort of movement during the movement of the cleaning unit 10. The sliding element 5 provides an optimal fit of the cleaning unit 10 on the drive shaft 3. The support surface of the cleaning unit 10 on the surface of the sensor housing 2 (at Figure 2 The support surface 5 (indicated by plane E1 in the figure) is also enlarged by the sliding element 5 without increasing the effort required to rotate the cleaning unit 10. The support surface thus stabilizes and supports the cleaning unit 10 in an optimal manner. Thus, for example, when forces occur radially on the cleaning unit 10 with respect to the axis X1, a supporting effect of the cleaning unit 10 on the sensor housing 2 is achieved.

[0033] The wiper element 30 is attached to the holding element 20, for example, by form fit. For example, the holding element 20 has a recess or groove to receive the wiper element 30 (see, for example, Figure 2 and Figure 4 ). The wiper element 30 is preferably made of rubber. The holding element 20 is preferably made of metal or plastic. The wiper element 30 and the holding element 20 can also be produced by a multi-component injection molding process, so that, for example, the holding element 20 is injection molded from plastic and the wiper element 30 is injection molded from rubber.

[0034] The wiper element 30 has a ring 31 which axially surrounds the retaining element 20 so that, when the retaining element 20 is mounted on the drive shaft 3, the ring 31 is in contact with the sensor housing 2 of the sensor 1 (see, for example, Figure 4 ). The ring 31 without the retaining element 20 is Figure 5 In addition to the ring 31 , the wiper element 30 preferably has a lip 34 .

[0035] The ring 31 has at least one tooth 32. The tooth 32 extends radially relative to the axis X1. Figures 5 to 8 As shown, the ring 31 has, for example, eight teeth 32. Any number of teeth 32 may be chosen. The number of teeth 32 is preferably a function of the angle of rotation of the cleaning unit 10, as will be explained below.

[0036] Figure 7 and Figure 8 The cleaning unit 10 and in particular the lip 34 are shown adapted to clean a predetermined area B of the sensor housing 2, for example an area of ​​the sensor housing 2 where a window (not shown) is arranged, when the cleaning unit 10 is moved by the drive shaft 3 at an angle W about the axis X1. Figure 7 The cleaning unit 10 is shown in a first, starting position. Figure 7 The arrow in denoted the moving direction of the cleaning unit 10 . Figure 7It is also shown that deposits A have accumulated in areas not swept by the lip 34. If these deposits are not removed, they may solidify over time, which may result in greater effort being expended when moving the cleaning unit 10.

[0037] Figure 8 The cleaning unit 10 is shown in Figure 7 Different positions. Here it is illustrated that the deposit A ​​is displaced due to the movement of the tooth 32 , but this occurs when the cleaning unit 10 is moved over the area B. FIG.

[0038] The number of teeth 32 is preferably selected such that when the cleaning unit 10 is rotated through the angle W, the deposits A are displaced.

[0039] In other words, the number of teeth 32 is selected and the teeth 32 are arranged on the ring 31 so that they pass all the way around when the cleaning unit 10 rotates at the angle W. This ensures that no deposits A accumulate between the teeth 32; instead, the deposits A are moved or removed by the teeth 32.

[0040] This means that when the cleaning unit 10 is rotated, for example, at an angle W of 90°, four teeth 32 evenly spaced from each other are arranged on the ring 31 so as to pass through all directions together. In this case, each tooth rotates at 90°, resulting in a full range of 360° achieved by the even spacing of the teeth.

[0041] The lip 34 extends radially relative to the axis X1 and is designed to come into contact with the sensor housing 2 when the retaining element 20 is mounted on the drive shaft 3 .

[0042] like Figure 5 and Figure 6 As can be seen in the figure, the lip 34 and the ring 31 are preferably constructed in one piece. This allows these elements to be replaced in one working step when the lip 34 and the ring 31 are replaced. In addition, it is thus ensured that when the lip 34 is released from the retaining element 20, the lip 34 cannot fall into the measured medium under any circumstances, because the ring 31 retains the lip 34.

[0043] like Figure 6 As can be seen in FIG. 3 , the tooth 32 has a cleaning surface 33. The cleaning surface 35 of the tooth is suitable for contacting the sensor housing 2. The lip 34 also has a cleaning surface 33. The cleaning surface 33 of the lip is also suitable for contacting the sensor housing 2. The two cleaning surfaces 33, 35 are preferably arranged in the plane E1. Thus, uniform cleaning of the sensor housing 2 is achieved.

[0044] Reference numerals list

[0045] 1 Sensor

[0046] 2 Sensor housing

[0047] 3 Drive shaft

[0048] 4 Screws

[0049] 5 Sliding element

[0050] 10 Cleaning unit

[0051] 20 Holding element

[0052] 30 Wiper element

[0053] 31 rings

[0054] 32 teeth

[0055] 33 Clean surface of lip

[0056] 34 Lip

[0057] 35 teeth cleaning surface

[0058] A Sediment

[0059] Area B

[0060] E1 plane

[0061] W angle

[0062] X1 axis

Claims

1. A cleaning unit (10) for a sensor (1), the sensor (1) having a sensor housing (2) and a drive shaft (3), the cleaning unit (10) comprising: a holding element (20) extending along an axis and suitable for being mounted on the drive shaft (3) so that the cleaning unit (10) can be moved by the drive shaft (3), a wiper element (30) which is fastened to the retaining element (20) and has a ring (31) which axially surrounds the retaining element (20) so that when the retaining element (20) is mounted on the drive shaft (3), the ring (31) is in contact with the sensor housing (2) of the sensor (1), wherein the ring (31) has at least one tooth (32) extending radially relative to the axis (X1), The wiper element (30) further comprises a lip (34), wherein the lip (34) is adapted to clean a predetermined area (B) of the sensor housing (2) when the cleaning unit (10) is moved by the drive shaft (3) around the axis (X1) at an angle (W), wherein the number of the teeth (32) is selected so that the teeth (32) are arranged on the ring (31) so that when the cleaning unit (10) rotates around the angle (W), the teeth (32) pass in all directions, thereby avoiding deposits between the teeth (32).

2. The cleaning unit (10) according to claim 1, wherein: The lip (34) extends radially relative to the axis (X1) and is designed to come into contact with the sensor housing (2) when the retaining element (20) is mounted on the drive shaft (3).

3. The cleaning unit (10) according to claim 2, wherein: The ring (31) and the lip (34) are formed in one piece.

4. The cleaning unit (10) according to one of the preceding claims, wherein The wiper element (30) is made of rubber.

5. The cleaning unit (10) according to one of claims 1 to 3, wherein: The holding element (20) and the wiper element (30) are produced by a multi-component injection molding process.

6. The cleaning unit (10) according to claim 2 or 3, wherein: The teeth (32) have a cleaning surface and the lip (34) has a cleaning surface, wherein both cleaning surfaces are arranged in a plane (E1).

7. The cleaning unit (10) according to one of the preceding claims 1 to 3, wherein The holding element (20) is detachably attached to the drive shaft (3).

8. The cleaning unit (10) according to claim 7, wherein: The retaining element (20) is attached to the drive shaft (3) by means of screws (4).

9. A sensor (1) having a cleaning unit (10) according to one of the preceding claims, wherein: The sensor (1) has a sensor housing (2) and a drive shaft (3), and the cleaning unit (10) is attached to the drive shaft (3).

10. The sensor (1) according to claim 9, wherein: A sliding element (5) is arranged on the drive shaft (3) between the cleaning unit (10) and the sensor housing (2).

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