Sensor system for detecting the rotational movement of a shaft

Abstract

Sensor system (100) for detecting the rotational movement of a shaft (101), comprising: a housing (1) having a connection cable opening (1.2.3) in a housing end wall (1.2.1) and adapted to be mounted on a shaft end (101.1) of the shaft (101) to be detected, a printed circuit board (6) arranged in the housing (1), a connection device (9) for connecting a connection cable (102), which is arranged adjacent to the connection cable opening (1.2.3) on a side facing the connection cable opening (1.2.3) on the printed circuit board (6), and a circuit board cover element (11) which is arranged between the circuit board (6) and the housing end wall (1.2.1) and has a receiving space (11.3) open in the direction of the housing end wall (1.2.1), wherein in a receiving space bottom wall (11.3.1) of the receiving space (11.3) a connection device opening (11.4) corresponding to the connection device (9) is formed, into which the connection device (9) is immersed in such a way, that the connection device (9) is accessible from the outside via the connection cable opening (1.2.3) and the receiving space (11.3), characterized in that a gap (13) between an outer peripheral surface (11.1) of the circuit board cover element (11) and an inner peripheral surface (1.2.2.1) of the housing (1) is sealed by a housing seal (12), and a gap (14) between an inner peripheral surface (11.4.1) of the connection device opening (11.4) of the circuit board cover element (11) and an outer peripheral surface (9.1) of the connection device (9) is sealed by a connection device seal (10).

Description

[0001] The present invention relates to a sensor system for detecting the rotational movement of a shaft, comprising: a housing having a connecting cable opening in a housing end wall and configured to be mounted on a shaft end of the shaft to be detected, a printed circuit board arranged in the housing, a connection device for connecting a connecting cable, which is arranged adjacent to the connecting cable opening on a side of the printed circuit board facing the connecting cable opening, and a printed circuit board cover element arranged between the printed circuit board and the housing end wall and having a receiving space open in the direction of the housing end wall, wherein a connection device opening corresponding to the connection device is formed in a receiving space bottom wall of the receiving space, into which the connection device is inserted in such a way thatthat the connection device is accessible from the outside via the connection cable opening and the receiving space.

[0002] Such a sensor system is known from WO 2018 / 219454 A1.

[0003] From DE 39 37 190 A1 a housing for an electronic circuit is known, which comprises a circuit receiving space and a connection device for a detachable electrical connection of information and supply lines.

[0004] From DE 198 03 358 A1 a housing for accommodating components is known, which comprises a trough-shaped lower part and a hood-shaped upper part, wherein the upper part has a sealing ring on the edge of its side wall and the lower part has a step running around the inside of its side wall as a support surface for the sealing ring.

[0005] From WO 92 / 11 745 A1, a multi-part RF-shielding housing for a circuit is known, which includes a printed circuit board and a plug, wherein the plug is connected to plug terminals mounted in the printed circuit board.

[0006] From DE 10 2007 018 759 A1 an angle sensor is known which has an axially short and radially wider design.

[0007] The present invention is based on the object of creating a reliable sensor system for detecting the rotational movement of a shaft.

[0008] This object is achieved by a sensor system for detecting the rotational movement of a shaft having the features of main claim 1.

[0009] The sensor system according to the invention for detecting the rotational movement of a shaft comprises a multi-part housing. The housing preferably comprises a pot-shaped housing part that forms a housing end wall and a housing peripheral wall of the housing and is preferably made of a material with good magnetic conductivity. The housing is designed to be fixedly mounted on a shaft end of the shaft to be detected in such a way that the shaft extends into the housing and can rotate within the housing. The housing is designed such that a rotor unit can be attached to the shaft end within the housing.A connection cable opening is formed in the front wall of the housing, through which a typically multi-core connection cable or a connecting element arranged at one end of the connection cable, for example a connecting plug, can be inserted into the housing to establish an electrical connection and / or a data connection with the sensor system.

[0010] The sensor system according to the invention for detecting the rotational movement of a shaft further comprises a circuit board arranged in the housing. Specifically, the circuit board is arranged such that, in the assembled state of the sensor system, the circuit board is arranged transversely to the shaft to be monitored and axially spaced from the shaft end. A sensor device is preferably arranged on the circuit board, which, during operation of the sensor system, interacts in a known manner, for example, magnetically, capacitively, or optically, with the rotor unit attached to the shaft end to detect the rotational movement of the shaft. The rotor unit preferably comprises at least one excitation magnet, and the sensor unit a so-called Wiegand sensor.Preferably, an evaluation device is also arranged on the circuit board, which typically comprises a so-called ASIC or a microcontroller and is configured to evaluate sensor signals provided by the sensor device in order to detect the rotational movement of the shaft in a known manner.

[0011] The sensor system according to the invention for detecting the rotational movement of a shaft further comprises a connection device for connecting the connecting cable to the circuit board. The connection device is arranged adjacent to the connecting cable opening on a side of the circuit board facing the connecting cable opening, so that the connecting cable or the connecting element arranged thereon can be connected to the connection device through the connecting cable opening. The connection device is preferably designed as a so-called printed circuit board connector.

[0012] The sensor system according to the invention for detecting the rotational movement of a shaft further comprises a printed circuit board cover element arranged between the printed circuit board and the housing end wall of the housing and essentially completely filling an inner cross-section of the housing, so that only a relatively narrow gap exists between an outer peripheral surface of the printed circuit board cover element and an inner peripheral surface of the housing peripheral wall of the housing. The printed circuit board cover element has a pocket-shaped receiving space open toward the housing end wall, specifically toward the connecting cable opening.In a receiving space floor wall of the receiving space, which delimits the receiving space in the direction of the circuit board, a connection device opening is formed that corresponds to the connection device. The connection device extends into this opening from a side of the receiving space floor wall opposite the receiving space in such a way that the connection device is accessible externally via the connection cable opening and the receiving space for connecting the connection cable. The connection device opening is formed such that only a relatively narrow gap exists between an inner circumferential surface of the connection device opening and an outer circumferential surface of the connection device.

[0013] According to the invention, the gap between the outer peripheral surface of the circuit board cover element and the inner peripheral surface of the housing peripheral wall of the housing is sealed by a housing seal, preferably designed as an O-ring, and the gap between the inner peripheral surface of the connection device opening of the circuit board cover element and the outer peripheral surface of the connection device is sealed by a connection device seal. The housing seal provided according to the invention and the connection device seal likewise provided according to the invention can reliably prevent contaminants potentially penetrating the housing via the connection cable opening, which could cause malfunctions and / or damage to electrical or electronic components located on the circuit board, from penetrating the circuit board area.This creates a reliable sensor system for detecting the rotational movement of a shaft.

[0014] Preferably, a circumferential groove is formed in the outer peripheral surface of the circuit board cover element, in which the housing seal is arranged. This makes it possible to easily and reliably prevent the housing seal from slipping out of the gap between the outer peripheral surface of the circuit board cover element and the inner peripheral surface of the housing peripheral wall of the housing.

[0015] In a preferred embodiment, the connector seal is clamped between the circuit board and the circuit board cover element and thus reliably secured, preventing the connector seal from slipping. Preferably, the connector seal rests against the circuit board cover element along the entire circumference of the connector and is pressed radially against the outer circumferential surface of the connector by the axial compression caused by the clamping. This reliably prevents contaminants from penetrating the circuit board area along the connector.

[0016] Preferably, the connection device seal has, on a side facing the circuit board cover element, a shoulder that protrudes in the direction of the circuit board cover element and extends into the gap between the inner circumferential surface of the connection device opening and the outer circumferential surface of the connection device. This allows for particularly reliable prevention of contaminants from penetrating the area of the circuit board along the connection device.

[0017] Preferably, a printed circuit board carrier element, to which the printed circuit board is attached, is arranged on a side of the printed circuit board facing away from the printed circuit board cover element. A gap between an outer peripheral surface of the printed circuit board carrier element and the inner peripheral surface of the housing is sealed by an additional housing seal, preferably designed as an O-ring. This allows the penetration of contamination into the area of the printed circuit board to be particularly reliably prevented. Preferably, a circumferential groove is formed in the outer peripheral surface of the printed circuit board carrier element, in which the additional housing seal is arranged.

[0018] In a preferred embodiment, the sensor system according to the invention comprises a cover element that partially closes the connecting cable opening in the assembled state. Preferably, the cover element essentially completely closes an area of the connecting cable opening that, in the assembled state of the sensor system, is not filled by the connecting cable connected to the connection device or a cable guide advantageously arranged in the connecting opening. This can prevent coarse contaminants from penetrating the housing.

[0019] Preferably, the connecting cable opening extends into the peripheral wall of the housing, and a portion of the connecting cable opening formed in the end wall of the housing is substantially completely closed by the cover element in the assembled state. In this embodiment, the connecting cable is inserted laterally into the housing through the portion of the connecting cable opening formed in the peripheral wall of the housing, wherein the portion of the connecting cable opening formed in the peripheral wall of the housing is configured such that it is substantially completely filled by the connecting cable and the cable guide advantageously arranged in the connecting opening.

[0020] Preferably, the cover element is arranged in the connecting cable opening and rests against a circuit board cover element end wall facing the housing end wall, thereby reliably preventing coarse contaminants from penetrating the receiving space of the circuit board cover element. Preferably, the cover element is substantially flush with an outer side of the housing end wall.

[0021] Particularly preferably, a labyrinth sealing device, i.e., a sealing device whose sealing effect is based on an increase in the flow path length, is formed between the cover element and the circuit board cover element end wall in order to prevent even finer contaminants from penetrating the receiving space. For example, the cover element and the circuit board cover element can have correspondingly designed, interlocking stepped profiles.

[0022] Preferably, the cover element is fastened to the circuit board cover element in the assembled state.

[0023] Particularly preferably, the cover element is attached to the circuit board cover element in the assembled state via a preferably removable snap connection. This enables easy installation of the cover element. Preferably, a protruding locking means is formed on the cover element, which engages and locks into a locking recess in the circuit board cover element that corresponds to the locking means.

[0024] It is expressly pointed out that the cover element described above can also be used to create a reliable sensor system for detecting the rotational movement of a shaft independently of the housing seal and the connection device seal, so that the cover element described above essentially represents an independent invention.

[0025] An embodiment of the present invention is described below with reference to the accompanying figures. Herein: Fig. 1 schematically shows a sensor system according to the invention mounted on a shaft for detecting the rotational movement of a shaft in a sectional view, and Fig. 2 an enlarged view of the Fig. 1 marked section II, Fig. 3 a top view of the sensor system Fig. 1, but without a cover element and without a connecting cable, Fig. 4 a printed circuit board of the sensor system arranged on a carrier element Fig. 1, Fig. 5 a circuit board cover element of the sensor system Fig. 1, and Fig. 6 a cover element of the sensor system Fig. 1.

[0026] The figures show a sensor system 100 according to the invention, which is mounted on a shaft 101, in particular on a shaft end 101.1 of the shaft 101, in order to detect its rotational movement.

[0027] The sensor system 100 comprises a housing 1, which consists of a housing base part 1.1 extending substantially transversely to the shaft 101, which forms a housing base wall 1.1.1, and a pot-shaped housing part 1.2, which forms a housing end wall 1.2.1 and a housing peripheral wall 1.2.2, and has a circular cross-section.

[0028] In the housing base part 1.1., a shaft opening 1.1.2 is formed through which the shaft end 101.1 extends into the housing 1.

[0029] In the pot-shaped housing part 1.2, a connecting cable opening 1.2.3 is formed, which extends from the housing end wall 1.2.1 into the housing peripheral wall 1.2.2 and through which a connecting cable 102 extends into the housing 1.

[0030] The sensor system 100 comprises a rotor unit 2, which is arranged in the housing 1 and fastened to the shaft end 101.1, and which comprises a plurality of permanent magnets 2.1.

[0031] The sensor system 100 comprises a printed circuit board carrier element 3, which is arranged in the housing 1. The printed circuit board carrier element 3 radially surrounds the rotor unit 2 and has a circumferential groove 3.2 on an outer circumferential surface 3.1.

[0032] A lower housing seal 4 designed as an O-ring is arranged in the groove 3.2, which seals a gap 5 between the outer circumferential surface 3.1 of the circuit board carrier element 3 and an inner circumferential surface 1.2.2.1 of the housing circumferential wall 1.2.2 of the housing 1.

[0033] The sensor system 100 comprises a printed circuit board 6, which is arranged transversely with respect to the shaft 101 in the housing 1 and is fastened to the printed circuit board support element 3. A sensor device 7, an evaluation device 8, and a connection device 9 are arranged on the printed circuit board 6.

[0034] For reasons of clarity, only a magnetic field sensor 7.1, which is arranged concentrically to the shaft 101 on a side of the circuit board 6 facing the shaft 101, and a Wiegand sensor 7.2, which is arranged concentrically to the shaft 101 on a side of the circuit board 6 facing away from the shaft, are shown in the sensor device 7.

[0035] For reasons of clarity, only one electronic component 8.1 of the evaluation device 8, designed as an integrated circuit, is shown.

[0036] The connection device 9 is designed as a so-called printed circuit board connector and is arranged adjacent to the connection cable opening 1.2.3 on the side of the printed circuit board 6 facing away from the shaft and toward the housing end wall 1.2.1. A connector plug 102.1 arranged at one end of the connection cable 102 is inserted into the connection device 9.

[0037] A connection device seal 10 is arranged on the connection device 9 along the entire circumference on an outer circumferential surface 9.1 of the connection device 9, which seal is supported on the printed circuit board 6 and has a protruding shoulder 10.1 surrounding the connection device 9 on a side facing away from the printed circuit board 6.

[0038] The sensor system 100 comprises a circuit board cover element 11, which is arranged between the circuit board 6 and the housing end wall 1.2.1 in the housing 1. The circuit board cover element 11 is supported on the circuit board 6 and the housing end wall 1.2.1 and is connected to the circuit board support element 3 via pins 3.3 formed on the circuit board support element 3. The circuit board cover element 11 has a circumferential groove 11.2 on an outer peripheral surface 11.1.

[0039] An upper housing seal 12 designed as an O-ring is arranged in the groove 11.2, which seals a gap 13 between the outer peripheral surface 11.1 of the circuit board cover element 11 and the inner peripheral surface 1.2.2.1 of the housing peripheral wall 1.2.2 of the housing 1.

[0040] The printed circuit board cover element 11 has, in an area accessible via the connection cable opening 1.2.3, a pocket-shaped receiving space 11.3 which is open in the direction of the housing front wall 1.2.1.

[0041] In a receiving space floor wall 11.3.1 delimiting the receiving space 11.3 in the direction of the printed circuit board 6, a connecting device opening 11.4 is formed which corresponds to the connecting device 9, in particular to the outer circumferential surface 9.1 of the connecting device 9, into which the connecting device 9 is inserted, so that the connecting plug 102.1 can be plugged into the connecting device 9 from the outside via the connecting cable opening 1.2.3 and the receiving space 11.3.

[0042] On a side facing the circuit board 6, the connection device opening 11.4 is delimited by a shoulder 11.3.1.1 protruding from the receiving space floor wall 11.3.1 and extending around the connection device opening 11.4. The shoulder 11.3.1.1 of the receiving space floor wall 11.3.1 is pressed against the connection device seal 10 along the entire circumference of the connection device opening 11.4, i.e., along the entire circumference of the connection device 9, so that the connection device seal 10 is clamped between the circuit board 6 and the circuit board cover element 11. The shoulder 10.1 of the connection device seal 10 extends into a gap 14 between the outer circumferential surface 9.1 of the connection device 9 and an inner circumferential surface 11.4.1 of the connection device opening 11.4 and seals the gap 14.

[0043] The sensor system 100 comprises a cable guide element 15 which is fastened to the circuit board cover element 11 and covers an edge 11.3.2 of the receiving space 11.3 as well as an edge 11.2.2.2 of the housing peripheral wall 1.2.2, and on which the connecting cable 102 rests.

[0044] The sensor system 100 comprises a cover element 16, which is inserted into the connecting cable opening 1.2.3 and completely closes the part of the connecting cable opening 1.2.3 formed in the housing end wall 1.2.1. The cover element 16 is fastened to the circuit board cover element 11 via a snap connection formed by a locking means 16.1 formed on the cover element 16 and protruding from the cover element 16 and a locking recess 11.5 formed in the circuit board cover element 11. The locking means 16.1 dips into the locking recess 11.5 and snaps into place there. The cover element 16 rests against a circuit board cover element end wall 11.6 facing the housing end wall 1.2.1 and is essentially flush with the housing end wall 1.2.1.

[0045] A projection 16.2 is formed on the cover element 16, which protrudes into a portion of the connecting cable opening 1.2.3 formed in the housing peripheral wall 1.2.2 and ends flush on an outer side with a housing edge 1.2.3 located between the housing end wall 1.2.1 and the housing peripheral wall 1.2.2. The projection 16.2 of the cover element 16 bears against the connecting cable 102 and presses the connecting cable 102 against the cable guide 15. The projection 16.2 of the cover element 16 and the cable guide 15 are designed such that the portion of the connecting cable opening 1.2.3 formed in the housing peripheral wall 1.2.2 is essentially completely closed by the connecting cable 102, the cable guide 15, and the projection 16.2.

[0046] On an inner side of the cover element 16 facing the circuit board cover element 11, a projecting shoulder 16.3 is formed, which forms a step profile 16.4 that interacts with a step profile 11.6.1 formed in the circuit board cover element end wall 11.6 to form a labyrinth sealing device 17 between the cover element 16 and the circuit board cover element 11. List of reference symbols 100 sensor system 1 housing 1.1 Housing base part 1.1.1 Housing base wall 1.1.2 Shaft opening 1.2 pot-shaped housing part 1.2.1 Housing front wall 1.2.2 Housing peripheral wall 1.2.2.1 Inner circumferential surface 1.2.2.2 Edge 1.2.3 Connection cable opening 2 rotor unit 2.1 Permanent magnets 3 PCB carrier element 3.1 Outer peripheral surface 3.2 Groove 3.3 Pens 4 Housing seal 5 gap 6 circuit board 7 Sensor device 7.1 Magnetic field sensor 7.2 Wiegand sensor 8 Evaluation device 8.1 Electronic component 9 Connection device 9.1 Outer peripheral surface 10 Connection device seal 10.1 paragraph 11 PCB cover element 11.1 Outer peripheral surface 11.2 Groove 11.3 Recording room 11.3.1 Recording room floor wall 11.3.1.1 Paragraph 11.3.2 Edge 11.4 Connection device opening 11.4.1 Inner peripheral surface 11.5 Recess 11.6 PCB cover element front wall 11.6.1 Step profile 12 Housing seal 13 gap 14 gap 15 Cable management element 16 Cover element 16.1 Restraints 16.2 Lead 16.3 paragraph 16.4 Step profile 17 Labyrinth sealing device 101 Wave 101.1 Shaft end 102 connection cables 102.1 Connector

Claims

[1] Sensor system (100) for detecting the rotational movement of a shaft (101), comprising: a housing (1) having a connection cable opening (1.2.3) in a housing end wall (1.2.1) and adapted to be mounted on a shaft end (101.1) of the shaft (101) to be detected, a printed circuit board (6) arranged in the housing (1), a connection device (9) for connecting a connection cable (102), which is arranged adjacent to the connection cable opening (1.2.3) on a side facing the connection cable opening (1.2.3) on the printed circuit board (6), and a circuit board cover element (11) which is arranged between the circuit board (6) and the housing end wall (1.2.1) and has a receiving space (11.3) open in the direction of the housing end wall (1.2.1), wherein in a receiving space bottom wall (11.3.1) of the receiving space (11.3) a connection device opening (11.4) corresponding to the connection device (9) is formed, into which the connection device (9) is immersed in such a way, that the connection device (9) is accessible from the outside via the connection cable opening (1.2.3) and the receiving space (11.3), characterized by , that a gap (13) between an outer peripheral surface (11.1) of the circuit board cover element (11) and an inner peripheral surface (1.2.2.1) of the housing (1) is sealed by a housing seal (12), and a gap (14) between an inner peripheral surface (11.4.1) of the connection device opening (11.4) of the circuit board cover element (11) and an outer peripheral surface (9.1) of the connection device (9) is sealed by a connection device seal (10). [2] Sensor system (100) according to claim 1, wherein a circumferential groove (11.2) is formed in the outer peripheral surface (11.1) of the circuit board cover element (11), in which groove the housing seal (12) is arranged. [3] Sensor system (100) according to one of the preceding claims, wherein the connection device seal (10) is clamped between the circuit board (6) and the circuit board cover element (11). [4] Sensor system (100) according to claim 3, wherein the connection device seal (10) has, on a side facing the circuit board cover element (11), a projecting shoulder (10.1) which dips into the gap (14) between the inner circumferential surface (11.4.1) of the connection device opening (11.4) and the outer circumferential surface (9.1) of the connection device (9). [5] Sensor system (100) according to one of the preceding claims, wherein a circuit board carrier element (3) is arranged on a side of the circuit board (6) facing away from the circuit board cover element (11), and wherein a gap (5) between an outer peripheral surface (3.1) of the circuit board carrier element (3) and the inner peripheral surface (1.2.2.1) of the housing (1) is sealed by a further housing seal (4). [6] Sensor system (100) according to one of the preceding claims, comprising a cover element (16) which partially closes the connection cable opening (1.2.3) in the assembled state. [7] Sensor system (100) according to claim 6, wherein the connecting cable opening (1.2.3) extends into a housing peripheral wall (1.2.2) of the housing (1) and a part of the connecting cable opening (1.2.3) formed in the housing end wall (1.2.1) is substantially completely closed by the cover element (16) in the assembled state. [8] Sensor system (100) according to claim 6 or 7, wherein the cover element (16) is arranged in the connection cable opening (1.2.3) and bears against a circuit board cover element end wall (11.6) of the circuit board cover element (11) facing the housing end wall (1.2.1). [9] Sensor system (100) according to claim 8, wherein a labyrinth sealing device (17) is formed between the cover element (16) and the circuit board cover element end wall (11.6). [10] Sensor system (100) according to one of claims 6 to 9, wherein the cover element (16) is fastened to the circuit board cover element (11) in the assembled state. [11] Sensor system (100) according to 10, wherein the cover element (16) in the assembled state is fastened to the circuit board cover element (11) via a snap connection (11.5,16.1).

Images