CN112539270B

CN112539270B - Transmission gear sensor

Info

Publication number: CN112539270B
Application number: CN201910896606.0A
Authority: CN
Inventors: 潘尚春
Original assignee: Hamlin Electronics Suzhou Co Ltd
Current assignee: Hamlin Electronics Suzhou Co Ltd
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2022-09-13
Anticipated expiration: 2039-09-20
Also published as: CN112539270A

Abstract

The invention provides a transmission gear sensor. The invention discloses a transmission gear sensor, comprising: a sensor assembly including a plurality of magnetic sensors disposed on a Printed Circuit Board (PCB) and spaced apart from each other along a first direction, the sensor assembly disposed within a sensor assembly housing; a magnet disposed within a magnet carrier housing that is slidably coupled to the sensor assembly housing and movable relative to the sensor assembly housing along an axis parallel to the first direction, the magnet carrier housing also being coupled to a gear shift device, wherein movement of the gear shift device results in movement of the magnet carrier housing relative to the sensor assembly housing, wherein all of the magnetic sensors are equidistant from the magnet in a second direction perpendicular to the first direction.

Description

Transmission gear sensor

Technical Field

The present disclosure relates generally to the field of automotive sensors, and more particularly to magnetic transmission gear sensors for automobiles.

Background

Many automobiles include a transmission gear sensor (sometimes also referred to as a "PRND position sensor") for determining the position of an automobile gear shifting device. The output from the transmission gear sensor may be communicated to the electrical system of the vehicle, which may prevent the vehicle from starting unless the shifting device is in, for example, a "park" position or a "neutral" position.

Some transmission range sensors utilize magnets and hall effect sensors to determine the position of an automotive shifting device. For example, a conventional transmission gear sensor may include a magnet carrier that is coupled to a gear shifting device of an automobile and holds a plurality of magnets. As the shifter is moved, the position of the magnet carrier moves relative to a plurality of hall effect sensors mounted on a printed circuit board located adjacent the magnet carrier. The output of the hall effect sensor is affected by the position of the magnetic field emitted by the magnet relative thereto and can therefore be used to determine the position of the gear shifting device.

Conventional transmission gear sensors include one hall effect sensor for each discrete position of the shifter (e.g., "park," "reverse," "neutral," and "forward") and a corresponding number of magnets. Thus, conventional transmission gear sensors may be relatively large and expensive due to the number of components required. Accordingly, it is desirable to provide a transmission gear sensor having a reduced size and reduced cost relative to conventional transmission gear sensors.

With respect to these and other considerations, the present disclosure may be useful.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter.

A transmission gear sensor according to a non-limiting embodiment of the present disclosure may include: a sensor assembly including a plurality of magnetic sensors disposed on a Printed Circuit Board (PCB) and spaced apart from each other along a first direction; and a magnet disposed adjacent to the PCB and movable along an axis parallel to the first direction, wherein all of the magnetic sensors are equidistant from the magnet in a second direction perpendicular to the first direction.

A transmission gear sensor according to another non-limiting embodiment of the present disclosure may include: a sensor assembly including a plurality of magnetic sensors disposed on a Printed Circuit Board (PCB) and spaced apart from each other along a first direction, the sensor assembly disposed within a sensor assembly housing; a magnet disposed within a magnet carrier housing that is slidably coupled to the sensor assembly housing and movable relative to the sensor assembly housing along an axis parallel to the first direction, the magnet carrier housing also being coupled to a gear shift device, wherein movement of the gear shift device results in movement of the magnet carrier housing relative to the sensor assembly housing, wherein all of the magnetic sensors are equidistant from the magnet in a second direction that is perpendicular to the first direction.

Drawings

FIG. 1A is a schematic diagram illustrating a side view of a transmission gear sensor according to an exemplary embodiment of the present disclosure;

FIG. 1B is a schematic diagram illustrating a plan view of the transmission gear sensor shown in FIG. 1A;

FIG. 2A is a graph showing the strength of the magnetic field emitted by the magnet of the transmission gear sensor shown in FIGS. 1A and 1B, as measured by the sensor of the transmission gear sensor and as a function of the position of the magnet in the Y direction;

fig. 2B is a graph showing a binary on/off signal and a gear corresponding to the analog signal shown in fig. 2A.

Detailed Description

A transmission gear sensor according to the present disclosure will now be described more fully with reference to the accompanying drawings, in which preferred embodiments of the transmission gear sensor are presented. However, the transmission gear sensor may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will convey certain exemplary aspects of the transmission gear sensor to those skilled in the art.

Fig. 1A and 1B schematically show a side view and a plan view, respectively, of a transmission gear sensor 10 (hereinafter "sensor 10") according to an exemplary embodiment of the present disclosure. For convenience and clarity, terms such as "top," "bottom," "above," "below," "vertical," "horizontal," "lateral," and "longitudinal" may be used herein to describe the relative positions and orientations of the various components of the sensor 10, the geometry and orientation of each component with respect to the sensor 10 as it is shown in fig. 1A and 1B. The terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.

As used herein, an element or operation recited in the singular and proceeded with the word "a" or "an" should be understood as not excluding plural elements or operations, unless such exclusion is explicitly recited. Furthermore, references to "one embodiment" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

The sensor 10 may generally include a sensor assembly 12 and a magnet carrier 14 that holds a magnet 15. The sensor assembly 12 and the magnet carrier 14 may include a sensor assembly housing 16 and a magnet carrier housing 18, respectively. The magnet carrier housing 18 may be coupled to the bottom of the sensor assembly housing 16 in a manner that facilitates linear movement between it and the sensor assembly housing. For example, the housings 16, 18 may be provided with mating track features or similar structures (not shown) that allow movement of the magnet carrier 14 relative to the sensor assembly 12 in directions parallel to the Y-axis of the illustrated cartesian coordinate system (hereinafter referred to as the "Y-direction") while preventing movement of the magnet carrier 14 relative to the sensor assembly 12 in directions parallel to the X-axis and Z-axis (hereinafter referred to as the "X-direction" and "Z-direction," respectively). The magnet carrier 14 may also be coupled, directly or indirectly, to a gear shift device 17 of the automotive transmission such that movement of the gear shift device 17 moves the magnet carrier 14 relative to the sensor assembly 12 in the Y direction as indicated by arrow 19.

The sensor assembly 12 may include a Printed Circuit Board (PCB)20 disposed within the sensor assembly housing 16 and lying in an XY plane. A plurality of hall effect sensors 22 a-22 d (hereinafter "sensors 22 a-22 d") may be disposed on the PCB20 in a longitudinally spaced arrangement (i.e., spaced apart in the Y-direction). Since the sensors 22a to 22d are all mounted on the surface of the PCB20, all of the sensors 22a to 22d may be evenly spaced from the magnet 15 in the Z-direction as shown by the gap g in fig. 1A. The longitudinal position of the sensors 22a to 22d in the Y direction may correspond to the park, reverse, neutral and forward positions of the gear shift device 17. In some embodiments, the longitudinal spacing between the sensors 22 a-22 d may be irregular (as shown in fig. 1A and 1B), with the spacing between the sensors 22a, 22B being less than the spacing between the sensors 22B, 22c, and the spacing between the

sensors

22c, 22d being greater than the spacing between the sensors 22B, 22 c. The present disclosure is not limited in this respect. In various embodiments, the longitudinal spacing of the sensors 22 a-22 d may be uniform.

Referring to fig. 1B, the sensors 22 a-22 d may be disposed on the PCB20 in a laterally staggered arrangement (i.e., staggered in the X-direction). In various embodiments, the position of the sensors 22 a-22 d along the X direction may be selected such that each sensor produces a desired or optimized output signal in response to longitudinal movement of the magnet 15 relative to the sensors 22 a-22 d, as described further below. For example, the sensors 22 a-22 d may be spaced apart from the Y-axis by a first distance d1, a second distance d2, a third distance d3, and a fourth distance d4, respectively, in the X-direction, wherein the first distance d1 is greater than the second distance d2, the third distance d3 is greater than the first distance d1, and the fourth distance d4 is greater than the first distance d1 but less than the third distance d 3. Exemplary positions (in millimeters) of each of the sensors 22 a-22 d relative to the illustrated cartesian coordinate system are provided in parentheses in fig. 1B. The present disclosure is not limited to the exemplary locations provided, and it is contemplated that the lateral/longitudinal spacing of the sensors 22 a-22 d may vary with respect to the arrangement shown in fig. 1B. In some embodiments, the sensors 22 a-22 d may not be laterally staggered, and all of the sensors 22 a-22 d may have the same position along the X-direction (e.g., all of the sensors 22 a-22 d may be disposed on the Y-axis).

Referring to fig. 2A, a graph of the strength of the magnetic field emitted by magnet 15, measured by each of sensors 22A-22 d, as a function of the position of magnet 15 in the Y-direction is shown. The closer the magnet 15 is to one of the sensors 22a to 22d in the Y direction, the stronger the magnetic field measured by that sensor. When the position of the longitudinal center of the magnet 15 in the Y direction is equal to the position of a specific one of the sensors 22a to 22d in the Y direction, the magnetic field measured by the sensor is strongest. For example, when the position of the magnet 15 in the Y direction is 8mm (the same position as the sensor 22 a), a signal peak associated with the sensor 22a is generated. When the position of the magnet 15 in the Y direction is 17mm (the same position as the sensor 22 b), a signal peak associated with the sensor 22b is generated. When the position of the magnet 15 in the Y direction is 28mm (the same position as the sensor 22 c), a signal peak associated with the sensor 22c is generated. When the position of the magnet 15 in the Y direction is 43.5mm (the same position as the sensor 22 d), a signal peak associated with the sensor 22d is generated.

The signals associated with each of the sensors 22a to 22d can be used to determine the position of the magnet 15 in the Y direction and thus the position of the gear change device of the vehicle relative to the park, reverse, neutral and forward positions in the vehicle transmission. For example, the signals measured by the sensors 22 a-22 d may be converted into corresponding binary "on/off" signals as shown in fig. 2B, wherein a signal exceeding a predetermined value (e.g., 7.6 millitess) may be interpreted as entering an "on" or "high" state, and wherein a signal falling below a predetermined value (e.g., 1.8 millitess) may be interpreted as entering an "off" or "low" state. As shown in fig. 1B, this determination may be made by a logic controller 30 (e.g., microcontroller, programmable logic controller, ASIC, etc.) connected to the sensors 22 a-22 d via the PCB 20. In a non-limiting example, it may be determined that the shift device of the automotive transmission is in the park position when the binary output of sensor 22a is high and the outputs of the other sensors 22 c-22 d are low. When the binary output of sensor 22b is high and the outputs of the

other sensors

22a, 22c, 22d are low, it can be determined that the shift device is in the reverse position. When the binary output of sensor 22c is high and the outputs of the

other sensors

22a, 22b, 22d are low, it can be determined that the shifting device is in the neutral position. When the binary output of sensor 22d is high and the outputs of the

other sensors

22a, 22b, 22c are low, it can be determined that the shift device is in the forward position. The present disclosure is not limited in this respect.

Notably, referring again to fig. 2A, the magnitude and width of the signal peaks associated with each of the sensors 22A-22 d are different from one another. This is due to the different lateral positions of the sensors 22a to 22d in the X direction (see fig. 1B). That is, the closer the sensor is located to the Y-axis (and thus to the magnet 15) in the X-direction, the greater the magnitude and width of the signal peak associated with the sensor. This may satisfy the requirements given by the automotive manufacturers, which stipulate that the gear sensor must generate a signal peak having a unique width associated with each of the park, reverse, neutral and forward gears of the automotive gearshift. The present disclosure is not limited in this regard and alternative embodiments of the sensor 10 are contemplated in which all of the sensors 22 a-22 d have the same position along the X-direction (e.g., all of the sensors 22 a-22 d may be disposed on the Y-axis).

In view of the foregoing, those of ordinary skill in the art will appreciate certain advantages that sensor 10 provides over conventional gear sensors in the art. For example, the sensor 10 requires only a single magnet 15 to generate a signal peak having a unique width associated with each of the park, reverse, neutral and forward gears of an automotive gear shift device, whereas conventional gear sensors typically require at least one magnet for each of the park, reverse, neutral and forward gears of the gear shift device to generate the required signal. Thus, the sensor 10 of the present disclosure is less complex and can be implemented at a lower cost relative to conventional gear sensors.

As used herein, an element or step recited in the singular and proceeded with the word "a" or "an" should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to "one embodiment" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

While the present disclosure refers to certain embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the spirit and scope of the present disclosure, as defined in the appended claims. Accordingly, it is intended that the disclosure not be limited to the described embodiments, but that it have the full scope defined by the language of the following claims, and equivalents thereof.

Claims

1. A transmission gear sensor comprising:

a sensor assembly including a plurality of magnetic sensors disposed on a Printed Circuit Board (PCB) and spaced apart from each other along a first direction; and

a magnet disposed adjacent to the printed circuit board and movable along an axis parallel to the first direction;

wherein all of the magnetic sensors are equidistant from the magnet in a second direction perpendicular to the first direction;

wherein the magnetic sensors are staggered on the printed circuit board along a third direction perpendicular to the first and second directions such that all of the magnetic sensors are spaced apart from the magnet by different distances along the third direction; and is

Wherein the magnet is not movable in the second direction or in the third direction relative to the magnetic sensor.

2. The transmission gear sensor of claim 1, wherein the magnetic sensor is a Hall effect sensor.

3. The transmission gear sensor of claim 1, wherein the spacing between the magnetic sensors in the first direction corresponds to the spacing between park, reverse, neutral, and forward positions of a gear shifting device in an automotive transmission.

4. The transmission gear sensor of claim 1, wherein the magnetic sensor is disposed within a sensor assembly housing and the magnet is disposed within a magnet carrier housing, and wherein the magnet carrier housing is slidably coupled to the sensor assembly housing.

5. The transmission gear sensor of claim 4, wherein the magnet carrier housing is adapted to be coupled to a gear shifting device of an automobile.

6. The transmission gear sensor of claim 1, wherein the magnetic sensors are connected to a controller that converts the analog signal generated by each magnetic sensor to a binary signal.

7. The transmission gear sensor of claim 6, wherein the controller is configured to determine a position of a shifting device based on the binary signal.

8. The transmission gear sensor of claim 1, wherein the magnitude of the signal generated by each magnetic sensor when the magnet is disposed closest to the magnetic sensor in the first direction is different than the magnitude of the signal generated by each of the other magnetic sensors when the magnet is disposed closest to these other magnetic sensors in the first direction.

9. A transmission gear sensor comprising:

a sensor assembly including a plurality of magnetic sensors disposed on a Printed Circuit Board (PCB) and spaced apart from each other along a first direction, the sensor assembly disposed within a sensor assembly housing; and

a magnet disposed within a magnet carrier housing slidably coupled to the sensor assembly housing and movable relative to the sensor assembly housing along an axis parallel to the first direction, the magnet carrier further coupled to a shift device, wherein movement of the shift device causes movement of the magnet carrier housing relative to the sensor assembly housing;

10. The transmission gear sensor of claim 9, wherein the magnetic sensor is a hall effect sensor.

11. The transmission gear sensor of claim 9, wherein the spacing between the magnetic sensors in the first direction corresponds to the spacing between park, reverse, neutral, and forward positions of the gear shift device.

12. The transmission gear sensor of claim 9, wherein the magnetic sensors are connected to a controller that converts the analog signal generated by each magnetic sensor to a binary signal.

13. The transmission gear sensor of claim 12, wherein the controller is configured to determine the position of the shifting device based on the binary signal.

14. The transmission gear sensor of claim 9, wherein a magnitude of a signal generated by each magnetic sensor when the magnet is disposed closest to the magnetic sensor in the first direction is different than a magnitude of a signal generated by each of the other magnetic sensors when the magnet is disposed closest to the other magnetic sensors in the first direction.