DE102021120695A1 - Sensor arrangement, sensor device and corresponding use - Google Patents

Abstract

The invention thus generally proposes a sensor arrangement (1) with at least one magnetic field sensor (2) which is mounted on a printed circuit board (3), a holder (4) holding the magnetic field sensor (2), the holder (4) having a fastening area ( 5) with which the holder (4) is mounted on the printed circuit board (3) and that at least one connecting leg (6) of the magnetic field sensor (2) is guided on the holder (4) to the fastening area (5), before, and that the magnetic field sensor (2) is pretensioned with a permanent magnet (11) and that the holder (4) has at least one holder (15) for the permanent magnet (11). The use of such a sensor arrangement (1) or a sensor device (16) is preferably of interest for measuring rotating objects such as engine shafts in the automotive industry, but is not limited to this area

Description

The invention relates to a sensor arrangement with a magnetic field sensor which is mounted on a printed circuit board by a holder. Such sensor arrangements or sensor devices are used industrially, for example, for monitoring rotating objects such as motor shafts.

The assembly of magnetically biased magnetic field sensors on printed circuit boards is a multi-step, relatively costly and time-consuming process. It is known that magnetic field sensors such as Hall sensors are glued onto a permanent magnet. Permanent magnets can be inserted through insertion openings in the printed circuit board and brought to ferromagnetic concentrator sheets. Due to the magnetic force, the permanent magnet can adhere permanently to the concentrator plate in the installation situation. The usually free-standing connection pins of the Hall sensor are inserted or positioned through holes in or on the printed circuit board using the THT (through-hole technology) method. The connecting legs of the magnetic field sensor are usually angled and are vertical in relation to the printed circuit board in known sensor arrangements. In a subsequent step, the connection pins of the magnetic field sensor are connected to the printed circuit board by soldering. It is also known that magnetic field sensors can be attached to a concentrator plate via a magnet, and that the concentrator plate can be attached directly to the printed circuit board by soldering using the SMT (surface-mounting technology) method. Finally, the legs of the magnetic field sensor are put through holes in the circuit board and soldered.

Furthermore, the invention includes an associated sensor device for detecting a rotational movement and/or rotational position of a rotating object with a sensor arrangement as described above.

The invention also relates to the use of such sensor arrangements and sensor devices.

The measurement of rotating objects, for example a magnetically conductive encoder wheel that is attached to a motor shaft, generally takes place as follows. The sensor wheel is equipped with measuring tracks, for example an A/B track and optionally a Z track, which can each be read out by a magnetically preloaded magnetic sensor. A measurement signal can thus be generated in each case, which allows conclusions to be drawn about the speed, angular position and/or the direction of movement of the encoder wheel. The measuring tracks can be formed very easily by means of teeth and recesses on the sensor wheel.

The object of the invention is to improve the sensor arrangement or sensor device described in the introduction.

To solve this problem, the features of claim 1 are provided according to the invention in a sensor arrangement. In particular, it is therefore proposed according to the invention to solve the problem in a sensor arrangement of the type described above that the magnetic field sensor is prestressed with a permanent magnet and that the holder has at least one holder for the permanent magnet. The advantage here is that the prestressed permanent magnet forms a magnetic field during a measurement, which means that a metal disk itself does not have to be magnetizable or magnetically coated, which can significantly simplify and reduce the production of a metal disk. A further advantage of such a sensor arrangement is a simplified, automated and cost-effective assembly of the magnetic field sensor on the printed circuit board, since the magnetic field sensor can be attached directly to the printed circuit board via the holder as an SMT component by reflow soldering.

Thus, the fastening area of the holder can be designed not only advantageously for mounting the holder on the printed circuit board, but also for making electrical contact with the connecting leg of the magnetic field sensor on the printed circuit board.

According to the invention, the object can also be achieved by further advantageous embodiments according to the dependent claims.

In a preferred embodiment of the invention it can be provided that the printed circuit board is arranged in a rear extension of the magnetic field sensor. Thus, advantageously, a required installation space transverse to a measuring direction can be kept as small as possible.

In a further embodiment it can be provided that one or the permanent magnet is arranged between the magnetic field sensor and the printed circuit board. Thus, a permanent magnet, for example the already mentioned one, can be arranged very advantageously between the magnetic field sensor and the printed circuit board, as a result of which even more space can be saved. A sensor arrangement can thus be used for measurements in a particularly small space.

According to a preferred embodiment of the invention it is provided that the holder by THT method and / or SMT method to at least at least one level of the circuit board is attached. Such an embodiment of the invention is very easy to install and advantageously stabilizes the holder together with the magnetic field sensor on the printed circuit board.

According to a further embodiment of the invention, it is provided that the at least one connecting leg of the magnetic field sensor is routed parallel to a plane of the printed circuit board. Thus, the at least one connecting leg advantageously takes up little space. Furthermore, a potential buckling of the at least one connection leg can be prevented as a result.

In addition, a free end of the at least one connecting leg guided to the printed circuit board can advantageously be electrically contacted to the printed circuit board in the fastening area.

In a further embodiment of the invention, it is provided that the at least one connecting leg of the magnetic field sensor is guided on the holder in a curved manner to the fastening area. A curved guidance of the at least one connecting leg can lead to a further saving of space in the sensor arrangement. Furthermore, it is extremely advantageous that a curvature of the at least one connecting leg can lead to the formation of at least one contacting section, which can be positioned favorably for electrical contacting on the printed circuit board.

According to a further embodiment of the invention, it is provided that the free end of the at least one connecting leg of the magnetic field sensor is surrounded by the holder. Protection of the free end of the at least one connecting leg is thus advantageously ensured by the holder.

In addition, the or a free end of the at least one connecting leg can be attached to the printed circuit board by THT methods or SMT methods, as a result of which the sensor arrangement can be stabilized. This can be implemented in particular in a contacting section to the printed circuit board that is at a distance from the free end.

In a further embodiment of the invention it is provided that the circuit board has a corresponding fastening area to the fastening area of the holder. Forming the respective fastening areas of the printed circuit board and holder with a precise fit facilitates assembly of a sensor arrangement according to the invention. It is advantageous here that the corresponding fastening area of the printed circuit board can lie flat against the fastening area of the holder. In addition, electrical contact points between the connecting legs of the magnetic field sensor and the printed circuit board can be implemented in a favorable manner with corresponding fastening areas.

Furthermore, at least one recess and/or soldering points can be provided in the corresponding fastening area of the printed circuit board. In this case, the at least one recess can fasten the holder to the printed circuit board in order to stabilize the holder. The at least one recess can also advantageously be used to attach the sensor device to an end user such as a measuring device.

The soldering points can be used for electrical contacting of the at least one connecting leg of the magnetic field sensor and/or for further fastening devices of the sensor device or an end user.

According to a further embodiment of the invention, it is provided that the holder is shaped for bending the at least one connecting leg of the magnetic field sensor. As a result, a magnetic field sensor can advantageously be simply positioned in the holder and aligned by bending the at least one connecting leg, which simplifies assembly.

Alternatively, the magnetic field sensor can be injected into the holder with at least one preferably bent connecting leg. The device consisting of holder and magnetic field sensor can thus be produced mechanically, inexpensively and quickly in one process.

In a further advantageous embodiment of the invention, it is provided that the holder is fastened with the fastening area along the printed circuit board. As a result, a space-saving sensor device can be implemented, which can be used advantageously for measurements in the smallest of spaces.

In a further embodiment of the invention it is provided that the magnetic field sensor is aligned transversally, preferably at an angle of 90°, to the plane of the printed circuit board. In this way, the magnetic field sensor can be aligned for measurements in the tightest of spaces. Alignment of the magnetic field sensor at an angle of 90° vertically to the printed circuit board is relatively stable and allows the sensor arrangement to be easily installed on a measuring device, for example. A transverse arrangement in relation to a plane can be characterized, for example, in that a characteristic plane can be specified which intersects the plane in a straight line and/or which encloses an angle of more than 0° and less than 180° with the plane. A special case is the (essentially) vertical arrangement or even an arrangement at an angle of 90°.

According to a further advantageous embodiment of the invention, it is provided that the permanent magnet is connected to a concentrator plate. The concentrator sheet can bring about a homogenization of the magnetic field provided by the permanent magnet, which has an advantageous effect on the quality of the measurement.

A concentrator plate can also be referred to as a homogenization plate.

In a further advantageous embodiment it can be provided that the holder has a receiving space for the concentrator plate and/or the permanent magnet. As a result, the concentrator plate and/or the permanent magnet can be easily integrated into a sensor arrangement.

Furthermore, the receiving space can be matched to a dimension and/or a cross section of the receiving part and/or the permanent magnet. As a result, relative displacements of individual components of the sensor arrangement can be avoided, as a result of which the sensor arrangement can be implemented in a compact manner for interference-free measurements.

It is possible that in one embodiment of the invention the receiving space can be matched to a dimension and/or a cross section of the receiving part and/or the permanent magnet. As a result, the concentrator plate and/or permanent magnet can be flexibly exchanged, which can be advantageous with regard to the longevity and applicability of a sensor device.

According to a further embodiment of the invention, it is provided that the concentrator plate is made of metal and/or is designed as a support plate. A metal concentrator plate can be shaped in such a way that the metal sensor and/or the permanent magnet can be positioned with an exact fit on the concentrator plate. The concentrator sheet metal, in particular the support sheet metal, can have holding devices that can be positioned exactly on the holder, as a result of which the concentrator sheet metal can be assembled in a robust manner.

A concentrator plate can also be made of a magnetically active material, in particular with the concentrator plate being magnetically bonded to the permanent magnet. The advantage here is that the permanent magnet can be held magnetically in the final installation position and/or during a measurement.

According to a further advantageous embodiment of the invention, it is provided that the holder has at least one holder for the permanent magnet, preferably a holder in which the permanent magnet can be attached, in particular without any gluing process. Thus, the permanent magnet can be built directly into the holder without a gluing process, which advantageously reduces the assembly time. For example, the permanent magnet can be mounted without adhesive and/or adhere due to its magnetic force.

In a further advantageous embodiment of the invention, it is provided that the at least one holder of the permanent magnet is matched to a dimension and/or a cross section of the permanent magnet. This allows the permanent magnet to be snapped into the holder very easily and positioned in a robust manner.

Alternatively, the at least one holder can be tunable in terms of a dimension and/or a cross section of the or further permanent magnets, as a result of which permanent magnets with different dimensions can be easily inserted and exchanged in the holder.

According to a further embodiment of the invention, it is provided that the at least one connecting leg of the magnetic field sensor is guided around the permanent magnet. The advantage here is that space can be saved in relation to the printed circuit board in a vertical orientation, as a result of which assembly of the sensor device on the end user can be facilitated.

According to a further advantageous embodiment of the invention, it is provided that the magnetic field sensor is a Hall sensor, Hall sensor ASIC or an XMR sensor, in particular an AMR, GMR or TMR sensor. The use of such sensors ensures particularly robust measurement signals.

Advantageously for the sensor arrangement, the magnetic field sensor can rest separately from the permanent magnet on a side of the concentrator plate facing away from the permanent magnet.

In order to solve the task mentioned at the outset, a sensor device is additionally or alternatively proposed for detecting a rotational movement and/or a rotational position of a rotating object. According to the invention, this sensor device has at least one sensor arrangement which is designed as described above and/or according to one of the claims directed to a sensor arrangement. Since this sensor device is based on the highly compact and easy-to-assemble sensor arrangements according to the invention, it can also be designed to be particularly compact and easy to assemble.

Finally, to achieve the stated object, the features of the subordinate claim directed to a use are provided according to the invention when using a sensor arrangement or a sensor device. In particular, it is therefore proposed according to the invention that a sensor arrangement according to the invention, in particular as described above and/or according to one of the claims directed to a sensor arrangement, or a sensor device as described above and/or according to the claim directed to a sensor device, for detecting a rotary movement and/or a rotational position of a rotating object. It is advantageous that the detection of a rotating movement, for example, is possible by the invention even in the smallest of spaces.

The invention will now be described in more detail using an exemplary embodiment, but is not limited to the exemplary embodiment. Further exemplary embodiments result from combining the features of individual or multiple claims with one another and/or with one or more features of the exemplary embodiment.

• 1 eine Leiterplatte als Basis einer erfindungsgemäßen Sensorvorrichtung mit einer Sensoranordnung,
• 2 eine assemblierte erfindungsgemäße Sensorvorrichtung mit einer Sensoranordnung,
• 3 eine Seitenansicht eines Querschnitts einer Sensorvorrichtung mit einer Sensoranordnung, und
• 4 eine Untersicht eines erfindungsgemäßen Halters.

It shows:

• 1 a printed circuit board as the basis of a sensor device according to the invention with a sensor arrangement,
• 2 an assembled sensor device according to the invention with a sensor arrangement,
• 3 a side view of a cross section of a sensor device with a sensor arrangement, and
• 4 a bottom view of a holder according to the invention.

1 shows a holder 4 which is connected to a printed circuit board 3 via a fastening area 5 . in the in 1 illustrated embodiment, two brackets 14 of the holder 4 are used in recesses 10 of the circuit board 3, whereby the sensor device 16 can be easily mounted and / or stabilized.

Alternatively, the holder 4 can also have one or more than two holders 14 . In addition, the at least one mount 14 can attach the sensor device 16 to an end user such as a measuring device. A holder-less connection between holder 4 and printed circuit board 3 is also conceivable.

A magnetic field sensor 2 is incorporated in the holder 4 and is aligned transversely (here vertically or 90°) to the printed circuit board 3, as a result of which a space-saving sensor arrangement 1 or sensor device 16 is implemented. It can be said that the circuit board 3 is arranged in a rearward extension of the magnetic field sensor 2 .

The at least one connecting leg 6 (not visible) of the magnetic field sensor 2 is guided through the holder 4 to the fastening area 5 of the holder 4 to the printed circuit board 3, where the free end 7 of the at least one connecting leg 6 is electrically contacted by soldering it to the printed circuit board 3, for example .

In an alternative embodiment, the at least one connecting leg 6 can also be electrically contacted to the printed circuit board 3 outside of the holder 4 .

To attach the holder 4 to the printed circuit board 3 and/or to make electrical contact with the at least one connecting leg 6 of the magnetic field sensor 2 on the printed circuit board 3, the fastening area 9 of the printed circuit board 3 can be designed completely corresponding to the fastening area 5 of the holder 4.

The 1 FIG. 1 also shows a cylindrical permanent magnet 11 and a precisely fitting support plate for the permanent magnet 11, designed as a concentrator plate 12, which are not yet installed in the receiving space 13. The dashed lines indicate assembly steps of the sensor arrangement 1 or sensor device 16 , the support plate being magnetically attached to the permanent magnet 11 and the permanent magnet 11 being fastened in the receiving space 13 by two holders 15 .

The receiving space 13 is in the 1 shown as a pit, but can be shaped differently depending on the design of the holder 4 and/or the permanent magnet 11 and oriented with respect to the printed circuit board 3 . For example, the receiving space 13 can be implemented as a horizontal surface as an extension of the printed circuit board 3 . The distance between the receiving space 13 and the printed circuit board 3 can also vary from the 1 deviate from the form shown, the distance may be shorter or longer.

In 2 a completely assembled sensor arrangement 1 or sensor device 16 according to the invention is shown. The magnetic field sensor 2 is connected to the support plate, which is attached to the permanent magnet 11 on its side facing away from the magnetic field sensor 2 . All three components just described are aligned transversally (here even vertically) to the printed circuit board 3 to save space.

As an alternative to the in 2 illustrated embodiment, the or a magnetic field sensor 2, the support plate or a concentrator plate 12 and the or a permanent magnet 11 can be oriented in a modified orientation to the printed circuit board.

3 shows a cross section of a sensor device 16 with a sensor arrangement 1 according to FIG 1 and 2 described embodiment of the invention. The at least one connecting leg 6 of the magnetic field sensor 2 runs below the permanent magnet 11 in the direction of the printed circuit board 3. The at least one connecting leg 6 is guided in the holder 4 and, after passing through the permanent magnet 11, is bent in the transverse (here vertical) direction.

Before reaching the printed circuit board 3 , the at least one connecting leg 6 is bent again and guided in the fastening area 5 of the holder 4 in the direction of the printed circuit board 3 . The attachment area 5 of the holder 4 is in contact with the attachment area 9 of the printed circuit board 3, which is designed to correspond to the attachment area 5 of the holder 4.

The at least one connecting leg 6 is bent twice more, so that a free end 7 of the at least one connecting leg 6 forms a contacting section 8 for making electrical contact with the printed circuit board 3 . This contacting section 8 of the at least one connecting leg 6 can be soldered onto the printed circuit board 3 using an SMT method, for example. In an alternative design, it is also conceivable that the free end 7 of the at least one connecting leg 6 is formed transversely (here vertically) to the printed circuit board 3 and is electrically contacted.

Depending on the design of the holder 4, the at least one connecting leg 6 may not be bent, bent once or bent more than once. The electrical contacting of the at least one connecting leg 6 can also be implemented as an alternative to the SMT method, for example the at least one connecting leg 6 can be inserted and soldered through a hole in the corresponding fastening area 9 of the printed circuit board 3 using the THT method.

In 4 a bottom view of a holder 4 which is connected to a guide plate 3 is shown. For clearer representation are in this 4 The magnetic field sensor 2, the support plate and the permanent magnet 11 are not shown. The holder 4 leads four connecting pins 6 of the magnetic field sensor 2 into the fastening area 5 of the holder 4. Here the free ends 7 of the four connecting pins each form a contact section 8. In the form shown here, the four connecting pins 6 with the magnetic field sensor 2 are injected into the holder 4 .

Alternatively, however, a holder 4 can also be constructed in such a way that a magnetic field sensor 2 is inserted into the holder, whereupon at least one connecting leg 6 of this magnetic field sensor can be bent.

The invention thus generally proposes a sensor arrangement 1 with at least one magnetic field sensor 2, which is mounted on a circuit board 3, with a holder 4 holding the magnetic field sensor 2, that the holder 4 forms a fastening area 5, with which the holder 4 is mounted on the circuit board 3 and that at least one connecting leg 6 of the magnetic field sensor 2 is guided on the holder 4 to the fastening area 5, and that the magnetic field sensor 2 is pretensioned with a permanent magnet 11 and that the holder 4 has at least one holder 15 for the permanent magnet 11. The use of such a sensor arrangement 1 or a sensor device 16 is preferably of interest for measuring rotating objects such as engine shafts in the automotive industry, but is not limited to this area.

Reference List

1

sensor arrangement

2

magnetic field sensor

3

circuit board

4

holder

5

Mounting area of the holder

6

leads

7

free end of the at least one connecting leg

8th

contacting section

9

Mounting area of the circuit board

10

recess

11

permanent magnet

12

concentrator plate

13

recording room

14

bracket

15

bracket

16

sensor device

Claims (19)

Sensor arrangement (1), with at least one magnetic field sensor (2) on a circuit board (3) is mounted, with a holder (4) holding the magnetic field sensor (2), that the holder (4) forms a fastening area (5) with which the holder (4) is preferably mounted flat on the printed circuit board (3), and that at least a connecting leg (6) of the magnetic field sensor (2) on the holder (4) is guided to the fastening area (5), characterized in that the magnetic field sensor (2) is pretensioned with a permanent magnet (11) and that the holder (4) is at least has a holder (15) for the permanent magnet (11). Sensor arrangement (1) according to the preamble of claim 1 or after claim 1 , characterized in that the circuit board (3) is arranged in a rear extension of the magnetic field sensor (2). Sensor arrangement (1) according to one of the preceding claims, characterized in that one or the permanent magnet (11) is arranged between the magnetic field sensor (2) and the printed circuit board (3). Sensor arrangement (1) according to one of the preceding claims, characterized in that the holder (4) is attached to at least one level of the printed circuit board (3) by the THT method and/or SMT method. Sensor arrangement (1) according to one of the preceding claims, characterized in that the at least one connecting leg (6) of the magnetic field sensor is guided parallel to a plane of the printed circuit board (3) and/or that a free end (7) of the at least one connecting leg (6 ) is electrically contacted to the printed circuit board (3) in the fastening area (5). Sensor arrangement (1) after claim 1 , characterized in that the at least one connecting leg (6) of the magnetic field sensor (2) on the holder (4) is curved out to the fastening area (5). Sensor arrangement (1) according to one of the preceding claims, characterized in that the free end (7) of the at least one connecting leg (6) of the magnetic field sensor (2) is surrounded by the holder (4), in particular ends in the holder (4), and/or that the free or one free end (7) of the at least one connecting leg (6) is attached to the printed circuit board by THT methods or SMT methods, in particular in a contacting section (8) spaced apart from the free end (7). Sensor arrangement (1) according to one of the preceding claims, characterized in that the circuit board (3) has a corresponding fastening area (9) to the fastening area (5) of the holder (4), that the corresponding fastening area (9) of the circuit board (3) lies flat against the fastening area (5) of the holder (4), and that the corresponding fastening area (9) of the printed circuit board (3) has at least one recess (10) and/or soldering points. Sensor arrangement (1) according to one of the preceding claims, characterized in that the holder (4) is shaped for bending the at least one connecting leg (6) of the magnetic field sensor (2) or that the magnetic field sensor (2) is provided with at least one preferably bent connecting leg (6 ) is injected into the holder (4). Sensor arrangement (1) according to one of the preceding claims, characterized in that the holder (4) is fastened with the fastening area (5) along the printed circuit board (3). Sensor arrangement (1) according to one of the preceding claims, characterized in that the magnetic field sensor (2) is aligned transversally, preferably at an angle of 90°, to the plane of the printed circuit board (3). Sensor arrangement (1) according to one of the preceding claims, characterized in that the magnetic field sensor (2) is pretensioned with a permanent magnet (11) and/or that the permanent magnet (11) is connected to a concentrator plate (12) and/or that the holder (4) has a receiving space (13) for the concentrator plate (12) and/or the permanent magnet (11) and that the receiving space (13) is adapted to a dimension and/or a cross section of the concentrator plate (12) and/or the permanent magnet (11) is tuned and/or tunable. Sensor arrangement (1) according to one of the preceding claims, characterized in that the concentrator plate (12) is made of metal and/or as a support plate and/or the concentrator plate (12) is made of a magnetically active material, in particular the concentrator plate with the permanent magnet ( 11) is magnetically attached. Sensor arrangement (1) according to one of the preceding claims, characterized in that the holder (4) has at least one holder (15) for the permanent magnet (11), preferably one holder (15) in which the permanent magnet (11) can be fastened , in particular without any gluing process and/or glue-free. Sensor arrangement (1) according to one of the preceding claims, characterized in that that the at least one holder (15) of the permanent magnet (11) is matched and/or can be matched to a dimension and/or a cross section of the permanent magnet (11). Sensor arrangement (1) according to one of Claims 10 until 13 , characterized in that the at least one connecting leg (6) of the magnetic field sensor (2) is guided around the permanent magnet (11). Sensor arrangement (1) according to one of the preceding claims, characterized in that the magnetic field sensor (2) is a Hall sensor, Hall sensor ASIC or an XMR sensor, in particular an AMR, GMR or TMR sensor and/ or that the magnetic field sensor (2) rests on a side of the concentrator plate (12) facing away from the permanent magnet (11). Sensor device (16) for detecting a rotational movement and/or a rotational position of a rotating object, having a sensor arrangement (1) according to one of the preceding claims. Use of a sensor arrangement (1) according to one of Claims 1 until 17 or a sensor device (16). Claim 18 for detecting a rotational movement and/or a rotational position of a rotating object.

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