HEIGHT LEVEL SENSOR WITH A BEARING HAVING A LOCKING MEANS

Description

[0001] The invention relates to a sensor according to the preamble of claim 1.

[0002] DE 10 2019 200 029 A1, DE 197 33 719 C1, DE 10 2011 118 775 B3 and DE 10 2012 106 021 A1 describe sensor arrangements each having a lever arm which is mounted in a housing or a base unit in a rotationally deflectable manner.

[0003] The invention is based on the object of proposing a sensor comprising a base unit and a lever unit, wherein the sensor is designed to be relatively cost-effective and / or robust and / or compact and / or to measure precisely.

[0004] This object is achieved according to the invention by the sensor according to claim 1.

[0005] The invention relates to a sensor having a lever unit which is mounted in a bearing of a base unit in a rotationally deflectable manner, wherein the lever unit has a shaft which is mounted in the bearing with its shaft bearing section, and a lever connected to this shaft, wherein the shaft has an encoder and wherein the base unit has at least one sensor element which detects the encoder or the magnetic field generated and / or modulated by the encoder, wherein the bearing of the base unit has a plurality of locking means, in particular locking hooks and / or locking projections, which are arranged circumferentially on the inner casing of the bearing and are formed integrally with the bearing, and wherein these locking means directly or indirectly hold and / or guide the shaft bearing section. Two spaced-apart rows of locking means, formed integrally with the bearing, are arranged circumferentially on the inner casing of the bearing.The shaft bearing section of the lever unit has a groove in which a snap ring is arranged, which is designed such that it can be received or is received or is mounted on the bearing side in a substantially form-fitting manner by the locking means or both rows of locking means.

[0006] Indirect holding and / or guiding of the shaft bearing section by the locking means is preferably understood to mean that a snap ring or another connecting means, which forms or enables a mutual positive connection between the bearing and the shaft bearing section, is held and / or guided and / or mounted by means of the locking means.

[0007] The bearing of the base unit is advantageously essentially cup-shaped or hollow-cylindrical.

[0008] The sensor is preferably designed as an angle sensor for measuring a rotation angle between the lever unit and the base unit.

[0009] The sensor is expediently designed as a chassis position sensor for detecting the relative deflection and / or position between a vehicle chassis and a chassis unit by means of an angle measurement of the sensor. For this purpose, the sensor has, in particular, a lever unit that is rotatably deflectably mounted in a bearing of a base unit. The lever unit has a shaft that is mounted in the bearing with its shaft bearing section, and a lever that is particularly preferably arranged substantially perpendicular to this shaft.

[0010] It is preferred that the lever unit is essentially formed in one piece from plastic, with the exception of the encoder, and that a housing of the base unit, in which at least the sensor element is arranged, is formed in one piece from plastic together with the bearing of the base unit.

[0011] The preferably substantially one-piece lever unit, with the exception of the encoder, preferably also has a connecting element integrally connected to the lever of the lever unit for coupling to a motor vehicle component.

[0012] Preferably, the shaft bearing section, in particular the entire lever unit, is made of carbon fiber-reinforced and / or glass fiber-reinforced plastic. The lever unit and the base unit are expediently made of PBT, or rather, the respective housing. These housings are each formed as a single piece and are produced in an injection molding process.

[0013] Advantageously, either the shaft bearing section, and in particular the entire lever unit, is made of carbon fiber-reinforced plastic, and the bearing of the base unit, in particular the bearing and the housing of the base unit together, is made of glass fiber-reinforced plastic, or alternatively, the shaft bearing section, and in particular the entire lever unit, is made of glass fiber-reinforced plastic, and the bearing of the base unit, in particular the bearing and the housing of the base unit together, is made of carbon fiber-reinforced plastic. In particular, both units are not made of carbon fiber-reinforced plastic at the same time, because this could potentially lead to electrical coupling due to the same choice of material.

[0014] An encoder is preferably understood to be a permanent magnet, which is in particular substantially cylindrical and magnetized substantially radially with respect to the shaft, particularly preferably diametrically. Alternatively, the encoder is preferably designed as a non-permanently magnetic, ferromagnetic target.

[0015] The sensor element is preferably understood to be a magnetic field sensor element, in particular a Hall element or a magnetoresistive magnetic field sensor element. Alternatively, the sensor element preferably has at least one energized conductor loop and detects the magnetic field modulated by the encoder or an electrical voltage induced in the conductor loop by the encoder. In particular, the sensor element has at least one generator conductor loop for generating a magnetic field and one or two receiver conductor loops in which the resulting induced electrical voltage is detected as a function of the magnetic field resulting from the generator conductor loop and the encoder.

[0016] The sensor element advantageously detects the magnetic field of the encoder or the magnetic field modulated by the encoder.

[0017] Preferably, the bearing of the base unit, in particular the entire base unit, is made of glass fiber reinforced plastic.

[0018] The preferred design of the shaft bearing section and / or the bearing made of carbon fiber reinforced plastic results in a reduction in surface friction between the shaft bearing section and the bearing due to the abrasion of plastic or carbon fiber.

[0019] In particular, the sensor is designed such that no grease or additional lubricant is incorporated into the bearing or the shaft bearing section. Alternatively, the bearing of the base unit or the shaft bearing section preferably comprises an additional lubricant or grease.

[0020] The locking means are preferably designed as locking hooks and / or locking projections and / or locking lugs.

[0021] It is preferred that the two rows of locking means are configured substantially parallel to one another. Particularly preferably, these two rows of locking means form a groove, most preferably an interrupted groove, on the inner surface of the bearing. This groove particularly advantageously does not protrude into the inner surface of the bearing, but is formed exclusively by the two rows of, in particular protruding, locking means.

[0022] The snap ring is preferably substantially round / circular or, alternatively, preferably not circular, but substantially oval or oval / round and wave-shaped. The ring is advantageously designed with interrupted sections.

[0023] It is preferred that the locking means of the at least one row along the circumferential direction or the inner circumference or the circumferential line or an inner circumferential line on the inner shell of the bearing each have a smaller or substantially equal width than / as the distances to the directly adjacent locking means.

[0024] It is preferred that the locking means of the at least one row are formed and arranged along the circumferential direction or the inner circumference or the circumferential line or an inner circumferential line on the inner shell of the bearing in each case substantially uniformly spaced from the respectively adjacent locking means, wherein the at least one row of locking means or in each case both rows of locking means spaced apart from one another each particularly preferably have six locking means.

[0025] It is expedient for the encoder to be arranged at the end of the shaft, on the side facing away from the lever, wherein this encoder is held exclusively in a form-fitting manner by the plastic body of the shaft and is particularly encompassed laterally, particularly preferably around its entire circumference. For this purpose, the shaft particularly preferably has two or three or more fingers or projections that fix the encoder laterally in a form-fitting manner, particularly with regard to the full height or axial extent of the encoder, wherein most preferably none of these fingers or projections supports the encoder from below. Expediently, the encoder is not connected to the shaft by adhesive.

[0026] It is preferred that the housing of the base unit has at least two fastening means, each comprising a thread or a substantially star-shaped recess, wherein the fastening means are designed such that a screw can be screwed into the material of the corresponding fastening means by at least partially cutting into the material of this fastening means. The fastening means are in particular made of plastic and are integrally connected to the housing of the base unit or are jointly formed integrally from plastic. Alternatively, one of the two fastening means is preferably designed as an element which can be positively inserted into a recess of a motor vehicle component and which is not screwed in and in particular has an insertion nose or insertable positioning aid, for example designed as a mandrel, which has an exemplary star-shaped or polygonal peripheral shape or such a profile.

[0027] The housing of the base unit preferably has at least two recesses, which are created during the formation of the housing and which each expose a portion of the sensor element and / or a signal processing element. In particular, in the area around these recesses, in particular at least 1 mm around these recesses, or the entire surface adjacent to the recess, the overmolded portion of the housing of the sensor element and / or the housing of the signal processing element is laser-activated, in particular prior to overmold formation. This, in particular, increases the adhesion or tightness between the housing and the sensor element or the signal processing element.

[0028] It is preferred that the shaft of the lever unit has a collar which is designed such that it engages around a circumferential edge or a circumferential upper edge of the essentially hollow-cylindrical bearing and is supported axially thereon. In particular, the collar and the circumferential upper edge of the bearing are designed such that the collar can engage with / on the edge or can be fixed / connected in a form-fitting manner. Particularly preferably, the bearing has a groove on its outer casing below the upper edge into which, for example, a lubricant or grease is introduced and into which, very particularly preferably, an annular seal is introduced, whereby the collar of the lever unit is sealed off from the bearing.

[0029] The lever unit conveniently has a collar at the transition between the lever and the shaft.

[0030] Preferably, the sensor is designed as an angle sensor and / or height sensor and / or chassis position sensor.

[0031] The shaft preferably has a substantially central recess which extends from the side of the lever as a blind hole in the direction of the base unit, wherein in particular this central recess is at least partially cylindrical and / or funnel-shaped and / or tapered.

[0032] The base unit expediently comprises a sensor element and a signal processing element, each of which is electrically contacted with and fastened to a leadframe. The leadframe projects into a connector, in particular with two parallel connection areas. The connector is expediently part of the housing of the base unit, and the sensor element, the signal processing element, and part of the leadframe are embedded or at least partially embedded in the housing, or the housing is formed during the encapsulation of these elements and part of the leadframe in a single injection molding process, wherein the bearing, the connector, and the fastening means are particularly preferably formed simultaneously as part of the housing.

[0033] The housing of the base unit preferably has at least two or three recesses, which are created during the formation of the housing and which each expose a part of the sensor element or the signal processing element. In particular, the sensor element or the integrated sensor and signal processing element is exposed by two opposing recesses. In the area around these recesses, the overmolded part of the housing of the sensor element or the signal processing element, i.e., the individual housing of these elements, is laser-activated, in particular before overmold formation. Furthermore, the housing of the base unit particularly preferably has additional, expediently two, centering recesses.

[0034] The sensor element and the signal processing element are expediently integrated as one component. Reference symbol

[0035] 1 Lever unit 11 Shaft 12 Lever 13 Shaft bearing section 14 Encoder 15 Means for laterally gripping the encoder 16 Collar of the lever unit 17 Groove 18 Snap ring 19 Essentially central recess 2 Base unit 21 Bearing 22 Sensor unit 23 Latching means 24 Fastening means of the base unit housing 25 Signal processing element 26 Circumferential edge of the bearing 27 Leadframe 28 Connector 29 Recesses of the base unit housing 30 Groove in the outer casing below the upper edge of the base unit bearing

[0036] They show in schematic representation Fig. 1 an embodiment of the sensor, Fig. 2 an exemplary lever unit, Fig. 3 an exemplary base unit Fig. 4 the exemplary sensor from Fig. 1 in a section, and Fig. 5Exemplary embodiment of the bearing and the shaft bearing section mounted therein in a section.

[0037] Fig. 1shows an embodiment of the sensor. The sensor comprises a lever unit 1 and a base unit 2. The lever unit consists of a lever 12, on which a shaft 11 with a shaft bearing section 13 is arranged, wherein the shaft bearing section 13 is inserted and mounted in bearing 21 of the base unit. At the lower end of the shaft bearing section 13, an encoder 14 is arranged, which is held exclusively in a form-fitting manner by exemplary projections or fingers 15 of the shaft bearing section. These projections 15 each encompass it laterally over its entire height, but they do not engage under or enclose the encoder 14. At the transition between the lever 12 and the shaft 11, the lever unit 1 has a collar 16, which encompasses the upper circumferential edge of the bearing 21 of the base unit 2. As an example, lever unit 1, with the exception of encoder 14, is made in one piece from carbon fiber reinforced plastic, in a single injection molding process.

[0038] At least the housing of the base unit 2, in which the sensor element 22 and the signal processing element 25 are both arranged and secured by a lead frame 27, and to which the fastening means 24 are attached, as well as the bearing 21 of the base element, are, for example, integrally formed from glass fiber reinforced plastic, specifically in a single injection molding process. The housing of the base unit 2 also forms a connector 28 with the lead frame as contacts.

[0039] One of the fastening elements 24 of the base unit, in the foreground in Fig. 1has an injected metal sleeve for screwing the sensor to a vehicle component (not shown). The rear fastening means 24 is designed, for example, as a mandrel with a star-shaped profile for insertion into a receptacle of the vehicle component (not shown). Bearing 21 of the base element has locking means 23, with which the shaft bearing unit is guided or mounted, for example indirectly by means of a snap ring.

[0040] Based on Fig. 4 is the embodiment from Fig. 1illustrated in a section, wherein the snap ring 18 is mounted on the side of the lever unit 1 in a groove 17 of the shaft bearing unit 13 and the snap ring 18 is also guided or mounted by the locking means 23 of the bearing 21 of the base unit 2. The locking means 23 are integrally connected to the bearing 21 and arranged on its inner surface circumferentially along an inner circumferential line or, for example, on essentially two mutually parallel inner circumferential lines, whereby the locking means 23 form an interrupted groove on the inner surface of the bearing 21.

[0041] The housing of the base unit 2 has three recesses 29, which are created during the construction of the housing and which expose a portion of the sensor element 22 on both sides and the signal processing element 25 on one side. In the area around these recesses 29, the overmolded part of the housing of the sensor element 22 or the signal processing element 25 is laser-activated, i.e., the individual housing of these elements, thereby ensuring a tight connection between the element housings and the housing of the base unit 2. The collar 16 of the lever unit 1 engages around the circumferential upper edge 26 of the bearing 21. The encoder 14 is arranged at the lower end of the shaft 11 and is held exclusively in a form-fitting manner by lateral engagement, with one of the projections 15 or fingers of the shaft being illustrated in this section.

[0042] Fig. 2shows an exemplary lever unit 1 with lever 12, which is formed essentially at a right angle to shaft 11. Shaft 11 comprises shaft bearing section 13, which can be inserted into the bearing of the base unit (not shown) and is mounted there for rotational movement. Shaft bearing section 13 has a circumferential groove 17, with which snap ring 18 can be connected or engages or dips into this groove. At the lower end of shaft 11, or end facing away from the lever, encoder 14 is attached by means of projections or fingers 15, which grip the encoder 14 on the sides and hold and fix the encoder 14 exclusively in a form-fitting manner. The projections or fingers 15 protrude downwards from shaft 11 essentially as far as the height of encoder 14 in this direction.

[0043] Based on the Fig. 3the base unit 2 is illustrated by way of example, which has a bearing 21, two fastening means 24 of the base unit and plug 28. Bearing 21 is essentially pot-shaped or hollow-cylindrical and has on its inner surface two essentially parallel rows of locking lugs as locking means 23, which together form an interrupted groove on the inner surface of the bearing 21, for receiving or supporting or guiding the snap ring (not shown), which in turn engages with the shaft bearing section (not shown) of the lever unit.

[0044] Fig. 5 shows, by way of example, a section through the bearing 21 of the base unit and the shaft bearing section 13 of the lever unit mounted there. The shaft preferably has a substantially central recess 19, which extends from the side of the lever 12 as a blind hole, tapering toward the base unit.

[0045] The shaft of the lever unit also has a collar 16, which is designed such that it engages around a circumferential edge 26 or a circumferential upper edge of the essentially hollow-cylindrical bearing 21 and is axially supported thereon. The collar 16 and the circumferential upper edge 26 of the bearing are designed such that the collar can engage with / on the edge or can be fixed / connected in a form-fitting manner. For example, the bearing 21 has a groove 30 on its outer surface below the upper edge 26, into which, for example, a lubricant or grease is introduced and into which, for example, an annular seal is introduced, whereby the collar 16 of the lever unit is sealed off from the bearing 21.

[0046] On the inner surface of the bearing 21, two spaced-apart rows of locking means 23 are arranged circumferentially (hatched differently here for visual clarity), but each formed integrally with the bearing. These two rows of locking means 23 are, as shown in the example, formed essentially parallel to one another and together form an interrupted groove on the inner surface of the bearing 23. This groove does not protrude into the inner surface of the bearing but is formed exclusively by the two rows of protruding locking means 23. A snap ring 18 is inserted into this interrupted groove of locking means 23 and the groove 17 on the shaft bearing section 13 and connects the shaft bearing section 13 and the bearing 21 in a form-fitting manner.

[0047] The base unit also has two fastening means 24.

[0048] At the end of the shaft, on the side facing away from the lever 12, the encoder 14 is arranged. This encoder 14 is held exclusively in a form-fitting manner by the plastic body of the shaft and is laterally encompassed. For this purpose, the shaft has several fingers or projections 15 that fix the encoder 14 laterally in a form-fitting manner with regard to its full height and axial extent. Sensor element 22 is embedded in the housing of the base unit below the encoder 14 or opposite it and is exposed on opposite sides by a recess 29 above and below the sensor element 22. The sensor element housing is laser-activated or laser-roughened in the area around the recess to ensure a tight connection to the injection-molded housing of the base unit.

Claims

1. Sensor which has a lever unit (1) which is rotationally deflectably mounted in a bearing (21) of a base unit (2), wherein the lever unit (1) has a shaft (11), which is mounted by way of its shaft bearing portion (13) in the bearing (21), and has a lever (12) connected to said shaft (11), wherein the shaft (11) has an encoder (14), and wherein the base unit (2) has at least one sensor element (22) which detects the encoder (14), wherein the bearing (21) of the base unit has multiple detent means (23), in particular detent hooks and / or detent projections, which are arranged in encircling fashion on the inner shell of the bearing (21) and which are formed as a single piece with the bearing, and wherein said detent means (23) directly or indirectly hold and / or guide the shaft bearing portion (13), characterized in that in each case two mutually spaced-apart rows of detent means (23) are arranged in encircling fashion on the inner shell of the bearing (21) so as to be formed integrally with the bearing (21), and in that the shaft bearing portion (13) of the lever unit (1) has a groove (17) in which a snap ring (18) is arranged, which snap ring is configured such that, at the bearing side, it is received substantially in form-fitting fashion by the two rows of detent means.

2. Sensor according to Claim 1, characterized in that the lever unit (1) is formed substantially, with the exception of the encoder (14), as a single piece from plastics, and in that a housing of the base unit (2), in which at least the sensor element (22) is arranged, is formed as a single piece from plastics together with the bearing (21) of the base unit (2).

3. Sensor according to at least one of the preceding claims, characterized in that the two rows of detent means (23) are configured to be substantially parallel to one another.

4. Sensor according to at least one of the preceding claims, characterized in that the detent means (23) of the at least one row each have a width along the peripheral direction / the inner circumference, on the inner shell of the bearing, which is smaller than the spacings to the directly adjacent detent means (23).

5. Sensor according to at least one of the preceding claims, characterized in that the detent means (23) of the at least one row are each formed and arranged so as to be substantially uniformly spaced apart, along the peripheral direction / the inner circumference, on the inner shell of the bearing (21), from the respectively adjacent detent means (23), wherein the at least one row of detent means (23), or each of the two mutually spaced-apart rows of detent means (23), each have in particular six detent means.

6. Sensor according to at least one of the preceding claims, characterized in that the shaft bearing portion (13), in particular the entire lever unit (1), is formed from carbon-fibre-reinforced plastics.

7. Sensor according to at least one of the preceding claims, characterized in that the bearing (21) of the base unit (2) is formed from glass-fibre-reinforced plastics.

8. Sensor according to at least one of the preceding claims, characterized in that the encoder (14) is arranged at the end of the shaft (11) on the side averted from the lever (12), wherein said encoder (14) is held exclusively in form-fitting fashion, and is in particular engaged around laterally, particularly preferably over its full circumference, by the plastics body of the shaft.

9. Sensor according to at least one of the preceding claims, characterized in that the housing of the base unit (2) has at least two fastening means (24) which each comprise a thread or a substantially star-shaped recess, wherein the fastening means (24) are configured such that a screw can be screwed into the material of the corresponding fastening means (24) by virtue of said screw at least partially cutting into the material of said fastening means (24).

10. Sensor according to at least one of the preceding claims, characterized in that the housing of the base unit (2) has at least two recesses (29) which are generated during the production of the housing and which each expose a part of the sensor element (22) and / or of a signal processing element (25).

11. Sensor according to Claim 10, characterized in that the overmoulded part of the housing of the sensor element (22) and / or of the housing of the signal processing element (25) is laser-activated in the region around said recesses (29), in particular before the overmoulding process.

12. Sensor according to at least one of the preceding claims, characterized in that the shaft (11) of the lever unit (1) has a collar (16), which is configured to engage around, and be supported axially on, an encircling edge (26) of the substantially hollow cylindrical bearing (21).

13. Sensor according to at least one of the preceding claims, characterized in that the sensor is configured as an angle sensor and / or ride height sensor and / or chassis position sensor.