Wheel speed sensor

Abstract

The present disclosure relates to a wheel speed sensor, which includes a sensor element and a fastening element. The sensor element has a rotation detection element for electromagnetic detection of the wheel speed of a vehicle, in particular a motor vehicle, and a sensor housing surrounding the rotation detection element. The fastening element has a fastening opening for vehicle-side fastening of the wheel speed sensor. The sensor element is surrounded by a guide sleeve for guiding and / or aligning and / or positioning the rotation detection element, wherein the guide sleeve is detachably connected to the sensor element and is fixable within a receiving portion of the fastening element.

Description

Technical Field

[0001] The present invention relates to a wheel speed sensor for measuring (preferably electromagnetic measurement of the wheel speed of a motor vehicle in particular). Background Art

[0002] To assist motor vehicle drivers in managing the increasing complexity and demands of road traffic, modern motor vehicles are equipped with various different driver assistance systems. In principle, vehicle-related or road traffic-related data is detected and analyzed in these systems and used to control the corresponding vehicle systems. The detection of the relevant data is carried out by sensors. The use of driver assistance systems such as Anti-Slip Regulation (ASR) prevents, for example, the rotation of the wheels during vehicle start-up, and the Antilock Braking System (ABS) prevents the wheels from locking during braking. Sensors are widely used for this purpose to accurately detect the speed of the motor vehicle wheels.

[0003] The measurement of the wheel speed is carried out in a non-contact manner by detecting the magnetic field fluctuations caused by the rotation of a detection object or a sensor rotor (such as an incremental wheel, a ferromagnetic gear or a pole wheel) that rotates together with the corresponding wheel. The actual wheel speed sensor for detecting the magnetic field position is arranged to be stationary at a short distance from the sensor rotor.

[0004] Wheel speed sensors are classified into active sensors and passive sensors based on their operating modes. Inductive passive sensors do not require a separate power supply. The inductive sensor has a coil and a permanent magnet, and the magnetic effect of the inductive sensor extends to the incremental wheel. The rotational movement of the incremental wheel and the alternation of the associated teeth and tooth gaps cause a change in the magnetic field. This change causes a measurable alternating current (AC) voltage. The frequency and amplitude of this AC voltage are proportional to the wheel speed.

[0005] Compared with passive wheel speed sensors, active wheel speed sensors are supplied with a defined voltage. The active sensor provides a signal with a constant amplitude independent of speed and uses the Hall effect when detecting the speed signal. For example, a ferromagnetic gear, a punching plate or a wheel with multiple poles applied is used as the detection object or the sensor rotor.

[0006] Wheel speed sensors are usually arranged in the immediate vicinity of the wheel whose speed is to be measured and are arranged on the corresponding transmission. There is an increased risk of corrosion in this environment. A series of protective shells and / or guide sleeves for the transition between the sensor head and / or the sensor head of the wheel speed sensor and the wiring harness are known from the prior art.

[0007] An electromagnetic wheel speed sensor having a sensor head, a gear, and a cable is known, for example, from CN 205898835 U. The sensor head has a permanent magnet, a pole axis, and an induction coil for measuring and generating an electromagnetic field. The output cable is guided by means of a cable conduit to the connection part of the fastening auxiliary device and is connected to the motor vehicle body by means of a hinged connection part.

[0008] CN 205273363 U discloses a connecting device made up of a wheel speed sensor and a wiring harness. The connection between the wiring harness and the wheel speed sensor includes an injection-molded part, wherein a part of the sensor head is enclosed using a housing. The housing includes a protection part that surrounds the connection between the wiring harness and the sensor head. The possibility of cable breakage can be reduced by the connecting device, thereby improving the reliability of the wheel speed sensor.

[0009] JP 2015 141 129 A also discloses a wheel speed sensor that includes a rotation detection element for detecting magnetic field fluctuations caused by the rotation of a rotor. The rotation detection element rotates together with a wheel of a vehicle and serves as a detection object. The detected rotation is converted into an electrical signal and transmitted to an output line through a conductor part of the rotation detection element. The output line is wrapped and buried in a covering member to ensure watertightness. The covering member is integrally implemented with a fixing member for vehicle-side fixing of the wheel speed sensor. A sealing element and a tubular element are provided on a side of the fixing member facing away from the sensor head.

[0010] JP 2008 268 016 A discloses a metal protective shell for a resin covering of a wheel speed sensor. The metal protective shell is used to avoid damage that may be caused by collision, adhesion, or solid movement on the resin covering of the wheel speed sensor. The protective shell is designed to surround the resin covering of the signal detection part of the wheel speed sensor. In particular, in the area of the rotating sensor rotor, separation of particles (especially iron powder) may occur, which may move due to the rotation of the sensor rotor and collide with the signal detection part. Therefore, the signal detection part is surrounded by a metal protective shell, which is in turn connected to the provided wheel speed sensor.

[0011] KR 2015 009 3008 A discloses a wheel speed sensor including a speed sensor unit, wherein a cable is connected to the speed sensor of a vehicle. An upper housing and a lower housing having an internal receiving groove for receiving the speed sensor unit are constructed separately from each other. The upper housing can be detachably connected to the lower housing. In this way, the same protective housing can be used to receive the wheel speed sensor independently of the structural design of the signal wheel and the vehicle-side fixing structure.

[0012] However, the wheel speed sensor itself made of plastic usually does not corrode. Corrosion often occurs on all the receiving parts that are usually connected to the wheel speed sensor. Especially in the wheel speed sensor (lateral measurement sensor) that requires a guiding piece, this risk is increased. The guiding function is subject to increased corrosion during assembly and is scratched or damaged in another way. In this way, the removal of the wheel speed sensor is usually only carried out when the damage rises to the level of sensor damage or is even completely impossible to carry out.

[0013] DE 10 2009 054 521 A1 discloses a fastening device for fastening the speed sensor housing of a wheel speed sensor to a vehicle. For this purpose, an adapter is provided, which includes a cylindrical body part. At one end of the body part, a fastening flange projects laterally. The fastening flange has drilled holes so that the adapter can be fastened by screws on the vehicle. The sensor housing is provided with two flat areas on its outer side, and these two flat areas form a twist lock with the corresponding inner surfaces of the cylindrical body part of the adapter to fix the wheel speed sensor in an exact alignment relative to the sensor wheel.

[0014] Considering the shown prior art, there is still room for improvement in the wheel speed sensor. Summary of the Invention

[0015] The present disclosure is based on the object of presenting a wheel speed sensor that can be easily replaced and / or maintained.

[0016] It should be noted that the features and measures listed separately in the following description can be combined with each other in any technically reasonable way and can disclose other embodiments of the present disclosure. This description also particularly characterizes and specifies the present disclosure in combination with the accompanying drawings.

[0017] The wheel speed sensor has a sensor element and a fastening element. The rotation detection element of the sensor element is surrounded by a sensor housing and is used for detecting (preferably electromagnetic detection of the wheel speed of a motor vehicle in particular). For this purpose, the wheel is provided with a sensor rotor that generates fluctuations in the electromagnetic field during rotation. The rotation detection element is arranged adjacent to and spaced apart from the sensor rotor to detect electromagnetic fluctuations. In order to fasten the sensor element to the vehicle side (for example, fastened on the axle part of the vehicle), the fastening element has a fastener such as a channel drilling for receiving a screw, for example.

[0018] According to the present disclosure, the sensor element is surrounded by a guiding sleeve for guiding and / or aligning and / or positioning the rotation detection element. In particular, the guiding sleeve is also used to protect the sensor housing and / or the rotation detection element from scratches, collisions, etc.

[0019] The guide sleeve is designed, for example, as a ring or sleeve with a cylindrical basic shape and a channel opening. The sensor element is arranged within the guide sleeve (e.g., within the channel opening) and is detachably connected to the guide sleeve. The connection between the guide sleeve and the sensor element is preferably formed such that the connection does not become detached during any possible transportation or other operations before the wheel speed sensor is connected to the vehicle wheel for operation. The guide sleeve can be fixed within the receiving portion of the fastening element in order to mount the wheel speed sensor. This means that the guide sleeve with the sensor element located therein can be introduced into the receiving portion of the fastening element and fixed therein, where the guide sleeve can be guided, aligned, and / or positioned by the receiving portion.

[0020] The guide sleeve can be fixed within the receiving portion such that during the removal of the wheel speed sensor (especially for maintenance, repair, and / or replacement of individual components), the guide sleeve does not become detached between the guide sleeve and the fastening element. Instead, the connection between the sensor element and the guide sleeve can be separated such that the sensor element is removable while the guide sleeve remains together with the fastening element in the installed state. This enables maintenance or replacement of the sensor element without damage and / or without destruction because corrosion-related effects can be excluded during installation and disassembly.

[0021] According to a preferred embodiment, the guide sleeve is detachably fixed within the receiving portion of the fastening element by form-fitting and / or friction locking, wherein the receiving portion of the fastening element and the guide sleeve are designed in particular for uniquely positioning and / or aligning the rotation detection element. For example, the distance and / or alignment of the rotation detection element relative to the vehicle-side sensor rotor can be set by small pieces, latches, and associated grooves using guide webs and slots, stop edges, and / or congruent surfaces each arranged complementarily to one another on the grooves of the guide sleeve and the fastening element. At the same time, detachably fixing the guide sleeve within the receiving portion of the fastening element can serve as a twist, tilt, and / or displacement lock.

[0022] The receiving portion of the fastening element is designed in a preferred embodiment as a receiving opening. The guide sleeve can be inserted into the receiving opening in a form-fitting manner and can be fixed, for example, by friction locking within the receiving opening.

[0023] If the guide sleeve contains a corrosion-resistant material (especially plastic) and / or is coated with or made of such a material, corrosion-related adhesion and / or jamming between the guide sleeve and the sensor housing, which is preferably also made of plastic, can be prevented. Thus, the connection between the sensor housing and the guide sleeve can be separated in a simple manner, whereby the sensor housing is removable from the channel opening of the guide sleeve.

[0024] For advantageous fixation to the fastening element, the guide sleeve has a fastening-side projection. The outer surface or outer peripheral geometry of the projection corresponds to the inner surface or inner peripheral geometry of the receiving opening of the fastening element such that the projection can be clamped or tensioned within the receiving opening. Additionally, it is advantageous that the outer peripheral geometry of the projection and the inner peripheral geometry of the receiving opening are formed asymmetrically such that the rotation detection element can be indirectly and uniquely aligned and / or positioned at a specific position relative to the sensor rotor via the guide sleeve.

[0025] Since the fastening element is used to align the guide sleeve, the function of the guide sleeve is separated from the availability of the fastening element. The receiving opening of the fastening element is not directly designed to align and guide the sensor housing but rather to align and guide the guide sleeve, whereby the positioning of the sensor element and / or the rotation detection element is only indirectly caused by the receiving opening of the fastening element.

[0026] Other advantageous embodiments of the present disclosure are disclosed in the following description of the figures. Description of the Drawings

[0027] Figure 1 A schematic view showing an exemplary embodiment of a wheel speed sensor with a fixed guide sleeve according to the present invention, and

[0028] Figure 2 As shown Figure 1 A schematic view showing an exemplary embodiment of a wheel speed sensor with a separable guide sleeve according to the present invention as shown. Detailed Description

[0029] As required, detailed embodiments of the present disclosure are disclosed herein; however, it should be understood that the disclosed embodiments are merely examples of the present disclosure, which may be implemented in various and alternative forms. These figures are not necessarily to scale; certain features may be exaggerated or minimized to show details of particular components. Accordingly, the specific structural and functional details disclosed herein should not be construed as limiting but merely as a representative basis for teaching one skilled in the art to use the present disclosure in various ways.

[0030] In the different figures, the same components always have the same reference numerals, which is why these components are generally only described once.

[0031] Figure 1Schematic diagram depicting an exemplary embodiment of a wheel speed sensor 100 according to the present disclosure, which includes a sensor element 110 and a fastening element 120. The sensor element 110 has a sensor housing 111 and a rotation detection element 112 disposed therein. The rotation detection element 112 is disposed within the wheel-side end 113 of the sensor housing 111 to detect magnetic field fluctuations caused by a sensor rotor (not shown). The opposite outer peripheral end 114 of the sensor housing 111 is for receiving a cable and / or a wire harness to convey the signal detected by the rotation detection element 112. A guiding sleeve 130 is coaxially disposed with the sensor housing 111, wherein the sensor housing 111 passes through a channel opening 131 of the guiding sleeve 130. The guiding sleeve 130 and the sensor housing 111 are detachably connected to each other. The guiding sleeve 130 further has a protruding portion 132 disposed at the wheel-side end of the guiding sleeve 130. The rotation detection element 112 protrudes beyond the sensor-side end of the guiding sleeve 130.

[0032] The fastening element 120 has a receiving opening 121 and a fastening opening 122. The fastening opening 122 is preferably circular in shape for receiving a screw with which the wheel speed sensor 100 can be fastened, in particular, to an axle of a vehicle. An inner sleeve 123 for anti-corrosion and / or sealing or having a similar function can be disposed within the fastening opening 122. The receiving opening 121 is preferably formed to penetrate the fastening element 120. The protruding portion 132 is disposed within the receiving opening 121, where the receiving opening 121 is completely filled by the protruding portion 132.

[0033] According to Figure 2 The illustration of Figure 1 shows an exemplary embodiment of the wheel speed sensor 100 according to

[0034] which the guiding sleeve 130 is not fixed within the receiving opening 121 but is disposed offset vertically with respect to the receiving opening 121. As can be seen by way of example, the circumferential shape of the outer surface 133 of the protruding portion 132 is formed as an asymmetric U-shape. The circumferential shape of the inner surface 124 of the receiving opening 121 is also formed as an asymmetric U-shape in a complementary manner to the outer surface 133 such that the alignment of the guiding sleeve 130 is only possible in a single specific position within the receiving opening 121. In this way, the sensor housing 111 having the rotation detection element 112 received therein can be directly or indirectly disposed and / or aligned with respect to the sensor rotor (not shown) at a specific position through the guiding sleeve 130 or the fastening element 120.

[0034] To remove the wheel speed sensor 100, the connection between the guiding sleeve 130 and the sensor housing 111 is separated, where the guiding sleeve 130 remains fixed within the receiving opening 121 (see Figure 1) Subsequently, the sensor housing 111 can be removed from the channel opening 131 of the guide sleeve 130, thereby maintaining the alignment of the guide sleeve 130 during reinstallation and / or eliminating the need for re-execution.

[0035] Although the exemplary embodiments have been described above, it does not mean that these embodiments describe all possible forms of the present disclosure. On the contrary, the words used in the specification are descriptive rather than restrictive, and it should be understood that various changes can be made without departing from the spirit and scope of the present disclosure. Additionally, the features of various implementation embodiments can be combined to form other embodiments of the present disclosure.

Claims

1. A wheel speed sensor, comprising: A sensor element having a rotation detection element for electromagnetic detection of wheel speed and a sensor housing surrounding the rotation detection element, A fastening element defining a fastening opening and a receiving opening, the receiving opening being defined by the inner surface of the fastening element as an asymmetric shape, and A guide sleeve, wherein the sensor element is surrounded by the guide sleeve, the guide sleeve guiding, aligning and positioning the rotation detection element, the guide sleeve being detachably connected to the sensor element, the guide sleeve having a fastening side protrusion, the outer surface of the fastening side protrusion being defined as an asymmetric shape complementary to the inner surface of the fastening element, the outer surface of the fastening side protrusion interacting with the inner surface of the receiving opening in a form-fitting and / or friction-locking manner such that the fastening side protrusion can be fixed in the receiving opening of the fastening element and the rotation detection element can be uniquely aligned and / or positioned.

2. The wheel speed sensor according to claim 1, wherein the fastening side protrusion of the guide sleeve has an outer peripheral surface corresponding to the inner surface of the receiving opening such that the fastening side protrusion can be clamped within the receiving opening.

3. The wheel speed sensor according to claim 1, wherein the fastening element has a receiving portion having an inner surface for uniquely positioning and / or aligning the rotation detection element.

4. The wheel speed sensor according to claim 3, wherein the receiving portion of the fastening element is formed as the receiving opening and the guide sleeve can be inserted into the receiving opening in a form-fitting manner.

5. The wheel speed sensor according to claim 1, wherein the guide sleeve comprises a corrosion-resistant material.

6. The wheel speed sensor according to claim 1, wherein the shape defined by the outer surface of the fastening side protrusion and the inner surface of the receiving opening of the fastening element is U-shaped.

7. A wheel, comprising: A housing that encloses a sensor having a rotational detection element for electromagnetically detecting the wheel speed; And A guide sleeve surrounding and detachably connected to the sensor, and the guide sleeve guiding, aligning and positioning the rotation detection element, the guide sleeve including a protrusion, A fastening element defining a receiving opening, the receiving opening being defined by the inner surface of the fastening element as an asymmetric shape; Wherein the outer surface of the protrusion of the guide sleeve is defined as an asymmetric shape complementary to the inner surface of the fastening element, the outer surface of the protrusion interacting with the inner surface of the receiving opening in a form-fitting and / or friction-locking manner such that the protrusion can be fixed in the receiving opening of the fastening element and the rotation detection element can be uniquely aligned and / or positioned.

8. The wheel according to claim 7, wherein the protrusion of the guide sleeve has an outer peripheral surface corresponding to the inner surface of the receiving opening such that the protrusion can be clamped within the receiving opening.

9. The wheel according to claim 7, wherein the guide sleeve is inserted into the receiving opening in a form-fitting manner.

10. The wheel according to claim 7, wherein the guide sleeve is formed of plastic.

11. The wheel according to claim 7, wherein the shape defined by the outer surface of the protruding portion and the inner surface of the receiving opening is U-shaped.

12. A wheel speed sensor, comprising: a fastening element that defines a fastening opening and a receiving opening, the fastening opening being configured to receive a fastener for connecting the fastening element to a vehicle, the receiving opening being defined by the inner surface of the fastening element as an asymmetrical shape; a sensor element having a rotation detection element for electromagnetic detection of the wheel speed and a sensor housing surrounding the rotation detection element; and a guide sleeve that is detachably connected to the sensor element and that guides, aligns, and positions the rotation detection element of the sensor, the guide sleeve having a fastening-side protruding portion, the outer surface of the fastening-side protruding portion being defined as an asymmetrical shape complementary to the inner surface of the fastening element, the outer surface of the fastening-side protruding portion interacting with the inner surface of the receiving opening in a form-fitting and / or friction-locking manner such that the fastening-side protruding portion can be fixed in the receiving opening of the fastening element and the rotation detection element can be uniquely aligned and / or positioned.

13. The wheel speed sensor according to claim 12, wherein the receiving opening is U-shaped.

14. The wheel speed sensor according to claim 13, wherein the outer circumference of the fastening-side protruding portion is U-shaped.

15. The wheel speed sensor according to claim 12, wherein the guide sleeve can be inserted into the receiving opening in a form-fitting manner.

16. The wheel speed sensor according to claim 12, wherein the guide sleeve is formed of plastic.

17. The wheel speed sensor according to claim 12, wherein the outer surface of the fastening-side protruding portion frictionally locks with the inner surface of the receiving opening.

18. The wheel speed sensor according to claim 17, wherein the outer surface of the fastening-side protruding portion and the inner surface of the receiving opening are formed asymmetrically such that the rotation detection element can be aligned and positioned.

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