Wheel speed sensors for vehicles

Abstract

A wheel speed sensor for a vehicle may include: a rotating component; an encoder unit mounted on the rotating component and rotated by the rotating component; a plurality of sensing units configured to sense signals from the encoder units; and a converter unit disposed between the sensing units and the encoder units and configured to convert the signals from the encoder units. The wheel speed sensor can accurately measure vehicle speed and quickly detect measurement errors.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a wheel speed sensor for a vehicle, and more particularly, to a wheel speed sensor for a vehicle that can convert a waveform of an encoder so that multiple sensors sense the same signal, thereby preventing measurement errors. Background Art

[0002] Generally, a service brake is a device used to slow down or stop a vehicle while in motion. Friction brakes have been used as service brakes in vehicles. Friction brakes convert the vehicle's kinetic energy into heat energy through mechanical friction, radiating the frictional heat into the atmosphere to achieve braking.

[0003] ABS (Anti-lock Braking System) is used as the vehicle's service brake. It controls the brake fluid pressure to ensure operational quality during sudden braking or emergency braking on slippery roads, improving braking performance by reducing stopping distance. ABS generally consists of a hydraulic unit that controls the fluid pressure supplied to the wheel cylinders based on control signals from the ECU (Electronic Control Unit), and a sensing unit that detects the rotational state of the wheels.

[0004] The sensing unit that detects the rotational state of the wheels is generally called a wheel speed sensor, and wheel speed sensors use Hall effect IC chips to sense the speed of each wheel. Wheel speed sensors are important elements of ABS / ESP (Electronic Stability Program) and provide important information for controlling other vehicle components.

[0005] The wheel speed sensor is connected to a back plate of the brake assembly and is configured to sense a rotation state of each wheel during driving by sensing rotation of a pulse ring located on the back plate.

[0006] However, in the related art, since the rotation of each wheel is measured by one sensor, measurement errors may occur in the event of sensor failure or damage. Therefore, a device that can solve this problem is needed.

[0007] A related art of the present disclosure is disclosed in Korean Patent Application Publication No. 2004-0009439, entitled “Method of Detecting Vehicle Speed ​​Using Speed ​​Sensor”, published on January 31, 2004. Summary of the Invention

[0008] Various embodiments are directed to a wheel speed sensor for a vehicle that can convert a waveform of an encoder so that a plurality of sensors sense the same signal, thereby preventing measurement errors.

[0009] In one embodiment, a wheel speed sensor for a vehicle may include: a rotating component; an encoder unit mounted on the rotating component and rotated by the rotating component; a plurality of sensing units configured to sense signals of the encoder units; and a converter unit disposed between the sensing units and the encoder units and configured to convert the signals of the encoder units.

[0010] The encoder unit may be a multi-pole magnetic pulse ring in which a plurality of N poles and a plurality of S poles are alternately arranged.

[0011] The encoder unit may be a gear made of ferromagnetic material.

[0012] The sensing unit may include: a first parallel sensing component configured to sense the signal of the encoder unit; and a second parallel sensing component disposed on one side of the first parallel sensing component and configured to sense the signal of the encoder unit with a time difference from the first parallel sensing component.

[0013] The converter unit may be mounted on either one of the first and second parallel sensing parts and convert the signal of the encoder unit to eliminate a time difference between the first and second parallel sensing parts.

[0014] The sensing unit may include: a first serial sensing component configured to sense the signal of the encoder unit; and a second serial sensing component disposed above the first serial sensing component and configured to sense the signal of the encoder unit simultaneously with the first serial sensing component.

[0015] The converter unit may be installed in any one of the first and second serial sensing parts and convert the signal of the encoder unit so that the first and second serial sensing parts have the same amplitude.

[0016] The sensing unit may include: one or more fixed sensing housings; and a pair of sensing chips embedded in the sensing housing and configured to sense the signal of the encoder unit, wherein either one of the pair of sensing chips measures the signal converted by the converter unit.

[0017] The converter unit can be installed in the sensor housing in a replaceable manner.

[0018] The pair of sensing housings may be disposed spaced apart from each other, and the pair of sensing chips may be embedded in the respective sensing housings.

[0019] The pair of sensing chips may be disposed in a sensing housing so as to be spaced apart from each other.

[0020] In a wheel speed sensor for a vehicle according to an embodiment of the present disclosure, a converter unit can convert the signal of an encoder unit so that multiple sensing units obtain the same measurement value even if their positions relative to the converter unit are different. Therefore, the wheel speed sensor can accurately measure vehicle speed and quickly detect measurement errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 FIG. 1 is a schematic diagram illustrating a wheel speed sensor for a vehicle according to an embodiment of the present disclosure.

[0022] Figure 2 FIG. 1 is a schematic diagram illustrating a sensing unit according to a first embodiment of the present disclosure.

[0023] Figure 3 FIG. 1 is a schematic diagram illustrating a sensing unit according to a second embodiment of the present disclosure.

[0024] Figure 4 Schematic diagram showing a setting state of a converter unit according to the first embodiment of the present disclosure.

[0025] Figure 5 2 is a schematic diagram showing a configuration state of a converter unit according to a second embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] Hereinafter, various exemplary embodiments of a wheel speed sensor for a vehicle will be described with reference to the accompanying drawings. It should be noted that the drawings are not drawn to exact scale and that the thickness of lines and the dimensions of components may be exaggerated for ease of description and clarity. Furthermore, the terms used herein are defined with consideration given to the functionality of the present invention and may vary depending on the user's or operator's preferences or intentions. Therefore, definitions of terms should be based on the overall disclosure set forth herein.

[0027] Figure 1 FIG. 1 is a schematic diagram showing a wheel speed sensor for a vehicle according to an embodiment of the present disclosure. Figure 1 A wheel speed sensor 1 for a vehicle according to an embodiment of the present disclosure includes a rotating member 10 , an encoder unit 20 , a sensing unit 30 , and a converter unit 40 .

[0028] The rotating component 10 rotates with the wheel. For example, the rotating component 10 may be a bearing that secures the rotating shaft of the wheel to a predetermined position and rotates the rotating shaft while supporting the weight and load applied to the rotating shaft. Alternatively, the rotating component 10 may be a wheel mounted with a tire.

[0029] The encoder unit 20 is mounted on the rotating component 10 and is rotated by the rotating component 10. More specifically, the encoder unit 20 may be a multi-pole magnetic pulse ring with a plurality of north poles and a plurality of south poles arranged alternately. For example, the encoder unit 20 may have 43 to 80 pole pairs. The encoder unit 20 may be a rubber magnetic encoder and include a magnetic material corresponding to at least one of ferrite, NdFeB, and Sm-Co. Alternatively, the encoder unit 20 may be a tone wheel using gears made of a ferromagnetic material.

[0030] The encoder unit 20 can have a single, dual, or triple track configuration. When the encoder unit 20 has a single track configuration, it can be configured as a single-layer multipole-pair magnetic pulse ring. When the encoder unit 20 has dual or triple tracks, it can be configured as a two-layer or three-layer multipole-pair magnetic pulse ring. These two-layer or three-layer multipole-pair magnetic pulse rings can have different multipole pair arrangements and / or different thicknesses. Because the encoder unit 20 is configured as a multipole-pair magnetic pulse ring with different multipole pair arrangements and / or different thicknesses, the sensing unit 30 can accurately measure the rotational speed of the wheel.

[0031] Multiple sensing units 30 sense signals from the encoder unit 20. For example, two sensing units 30 may be arranged in parallel or stacked vertically. The sensing units 30 can measure the rotational speed and direction of the rotating component 10, i.e., the rotational speed and direction of the wheel, by sensing changes in the magnetic field caused by the encoder unit 20 rotating the rotating component 10. Multiple sensing units 30 may be connected to a single board.

[0032] The converter unit 40 is provided between the sensing unit 30 and the encoder unit 20 and converts the signals from the encoder unit 20. That is, the values ​​measured by the multiple sensing units 30 may differ from one another because the sensing units 30 are located at different measurement positions relative to the encoder unit 20. However, the converter unit 40 can convert the signals from the encoder unit 20 so that the multiple sensing units 30 can obtain the same measurement value. Thus, the multiple sensing units 30 can measure the magnetic field individually, making it possible to detect operational errors between the encoder unit 20 and each sensing unit 30 and quickly check whether the sensing units 30 are functioning properly.

[0033] Figure 2 Schematic diagram showing a sensing unit according to the first embodiment of the present disclosure. Figure 2, the sensing unit 30 according to the first embodiment of the present disclosure includes a first parallel sensing component 51 and a second parallel sensing component 52. The first parallel sensing component 51 and the second parallel sensing component 52 both sense the signal of the encoder unit 20. At this time, the second parallel sensing component 52 is arranged on one side of the first parallel sensing component 51. Therefore, based on the rotation direction of the encoder unit 20, the first parallel sensing component 51 first measures the signal, and then the second parallel sensing component 52 measures the signal. Therefore, since there is a time difference between the first and second parallel sensing components 51 and 52 sensing the signal of the encoder unit 20, the sensed frequency has a constant amplitude but has a time difference therebetween. Since the first and second parallel sensing components 51 and 52 maintain a constant distance from each other, this structure can measure the correct amplitude.

[0034] Converter unit 40 is mounted on either of first and second parallel sensing components 51 and 52 and converts the signal from encoder unit 20 so that there is no time difference between the frequencies measured by first and second parallel sensing components 51 and 52. Therefore, first and second parallel sensing components 51 and 52 can measure the same amplitude within the same time zone. For example, converter unit 40 may include ferromagnetic material to stabilize or convert the magnetic field waveform.

[0035] Figure 3 FIG2 is a schematic diagram showing a sensing unit according to a second embodiment of the present disclosure. Figure 3 , the sensing unit 30 according to the second embodiment of the present disclosure includes a first serial sensing component 61 and a second serial sensing component 62. The first serial sensing component 61 and the second serial sensing component 62 both sense the signal of the encoder unit 20. At this time, the second serial sensing component 62 is arranged above the first serial sensing component 61. Therefore, based on the rotation direction of the encoder unit 20, the first and second serial sensing components 61 and 62 measure the signal at the same time. Therefore, although the first and second serial sensing components 61 and 62 sense the signal of the encoder unit 20 at the same time, since the distances between the first and second serial sensing components 61 and 62 and the encoder unit 20 are different from each other, the sensed frequencies may have different amplitudes. This structure can check the values ​​output by the first and second serial sensing components 61 and 62 in the same time zone, and quickly determine whether the first and second serial sensing components 61 and 62 are working properly.

[0036] The converter unit 40 is mounted on either of the first and second serial sensing components 61 and 62 and converts the signal of the encoder unit 20 so that the frequencies measured by the first and second serial sensing components 61 and 62 have the same amplitude. For example, the converter unit 40 may include a ferromagnetic material to stabilize or convert the magnetic field waveform.

[0037] Figure 4Schematic diagram showing a setting state of a converter unit according to the first embodiment of the present disclosure. Figure 5 Schematic diagram showing the arrangement of a converter unit according to a second embodiment of the present disclosure. Figure 4 and Figure 5 , the converter unit 40 according to an embodiment of the present disclosure may be mounted on the bottom surface of the sensing unit 30 and replaced as needed.

[0038] The sensing unit 30 includes a pair of sensing chips 32 embedded in one or more fixed sensing housings 31 and senses the signal from the encoder unit 20. The converter unit 40 can be mounted on the bottom surface of the sensing housing 31 and converts the signal from the encoder unit 20. The converter unit 40 can be screwed or hooked onto the sensing housing 31 and can be installed on or separated from the sensing housing 31. Therefore, when a sensing error occurs in the sensing unit 30 due to damage to the converter unit 40, the converter unit 40 can be replaced. In addition, even if the conversion rate of the converter unit 40 needs to be adjusted due to changes in the external environment, the converter unit 40 can be replaced.

[0039] When the pair of sensing housings 31 are separated and arranged to be spaced apart from each other, the sensing chip 32 is embedded in each sensing housing 31. At this time, when the converter unit 40 is installed in either of the two sensing housings 31, the sensing chip 32 embedded in the sensing housing 31 in which the converter unit 40 is installed can sense the converted signal ( Figure 4 ).

[0040] In addition, the pair of sensing chips 32 are spaced apart from each other and are disposed in one sensing housing 31. At this time, when the converter unit 40 is disposed toward any one of the sensing chips 32, the sensing chip 32 facing the converter unit 40 can sense the signal converted by the converter unit 40 ( Figure 5 ).

[0041] A mounting process and operation of the wheel speed sensor for a vehicle according to an embodiment of the present disclosure having the above-described structure will be described as follows.

[0042] When the first parallel sensing component 51 and the second parallel sensing component 52 are installed in parallel with each other (see Figure 2), the converter unit 40 is mounted on the first parallel sensing component 51. In this mounted state, a time difference occurs when the first parallel sensing component 51 and the second parallel sensing component 52 measure the signal of the encoder unit 20. Therefore, the measurement values ​​of the first parallel sensing component 51 and the second parallel sensing component 52 are different from each other. The converter unit 40 is disposed between the first parallel sensing component 51 and the encoder unit 20, and converts the signal of the encoder unit 20 for sensing by the first parallel sensing component 51. Therefore, the first parallel sensing component 51 that receives the virtual signal converted by the converter unit 40 can obtain the same measurement value as the measurement value measured by the second parallel sensing component 52 in the same time zone.

[0043] When the first serial sensing part 61 and the second serial sensing part 62 are stacked in series with each other (see Figure 3 ), the converter unit 40 is installed in the second serial sensing component 62. In this installation state, since the measurement distances between the first and second serial sensing components 61, 62 and the encoder unit 20 are different, the values ​​measured by the first and second serial sensing components 61, 62 are different from each other. The converter unit 40 is provided between the second serial sensing component 62 and the encoder unit 20, and converts the signal from the encoder unit 20 for sensing by the second serial sensing component 62. Therefore, the second serial sensing component 62, having received the virtual signal converted by the converter unit 40, can obtain the same amplitude measurement value as that measured by the first serial sensing component 61.

[0044] In the wheel speed sensor 1 for a vehicle according to an embodiment of the present disclosure, the converter unit 40 can convert the signal of the encoder unit 20 so that the multiple sensing units 30 obtain the same measurement value even if the positions of the multiple sensing units 30 relative to the converter unit 40 are different from each other. Therefore, the wheel speed sensor 1 can accurately measure the vehicle speed and quickly determine measurement errors.

[0045] Although exemplary embodiments of the present disclosure have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the disclosure as disclosed in the accompanying claims.

Claims

1. A wheel speed sensor for a vehicle, comprising: rotating parts; an encoder unit mounted on the rotating member and rotated by the rotating member; a plurality of sensing units including a first sensing unit and a second sensing unit separated from each other, the first sensing unit being configured to sense a signal from the encoder unit; as well as a converter unit, disposed between the encoder unit and the second sensing unit and configured to convert a signal of the encoder unit; The second sensing unit is configured to sense the signal converted by the converter unit.

2. The wheel speed sensor for a vehicle according to claim 1, wherein The encoder unit is a multi-pole magnetic pulse ring in which a plurality of N poles and a plurality of S poles are alternately arranged.

3. The wheel speed sensor for a vehicle according to claim 1, wherein The encoder unit is a gear made of ferromagnetic material.

4. The wheel speed sensor for a vehicle according to claim 1, wherein The sensing unit includes: a first parallel sensing component configured to sense a signal of the encoder unit; and The second parallel sensing component is disposed at one side of the first parallel sensing component and is configured to sense the signal of the encoder unit with a time difference from the first parallel sensing component.

5. The wheel speed sensor for a vehicle according to claim 4, wherein The converter unit is mounted on either one of the first and second parallel sensing parts and converts the signal of the encoder unit to eliminate a time difference between the first and second parallel sensing parts.

6. The wheel speed sensor for a vehicle according to claim 1, wherein The sensing unit includes: a first serial sensing component configured to sense a signal of the encoder unit; and The second serial sensing component is disposed above the first serial sensing component and is configured to sense the signal of the encoder unit simultaneously with the first serial sensing component.

7. The wheel speed sensor for a vehicle according to claim 6, wherein The converter unit is installed in either one of the first and second serial sensing parts and converts the signal of the encoder unit so that the first and second serial sensing parts have the same amplitude.

8. The wheel speed sensor for a vehicle according to claim 1, wherein The sensing unit includes: one or more fixed sensing housings; and a pair of sensing chips, embedded in the sensing housing and configured to sense the signal of the encoder unit, Wherein, either one of the pair of sensing chips measures the signal converted by the converter unit.

9. The wheel speed sensor for a vehicle according to claim 8, wherein The converter unit is replaceably mounted in the sensing housing.

10. The wheel speed sensor for a vehicle according to claim 8, wherein The pair of sensing housings are spaced apart from each other. Wherein, the pair of sensing chips are embedded in respective sensing housings.

11. The wheel speed sensor for a vehicle according to claim 8, wherein The pair of sensing chips are spaced apart from each other and are arranged in a sensing housing.

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