WO2011085854A2

WO2011085854A2 - Sensor arrangement with adjustment aid

Info

Publication number: WO2011085854A2
Application number: PCT/EP2010/068276
Authority: WO
Inventors: Jens Heim; Marc-Andre SCHÄFER
Original assignee: Schaeffler Technologies Gmbh & Co. Kg
Priority date: 2009-12-21
Filing date: 2010-11-26
Publication date: 2011-07-21
Also published as: DE102009059905A1; WO2011085854A3

Abstract

The invention relates to a sensor to be fixed to a carrier or a static component of a roller bearing, wherein a signal receiver contained in the sensor is provided for detecting a signal from a signal transmitter that can be displaced relative to the signal receiver. The aim of the invention is to devise a cost-effective, simple and safe manner to position the sensor within the carrier or the static component of the roller bearing. To this end, it is proposed to fix an adjustment aid in the direction of detection from the sensor to the signal transmitter to the sensor, to the signal transmitter or to another static component of the roller bearing, wherein the adjustment aid can later be removed without subsequently influencing the detection distance between sensor and signal transmitter or the adjustment aid is intended to remain on the sensor, wherein the force-fit between adjustment aid and signal transmitter is released by the operation of the roller bearing. The adjustment aid can be applied as a layer and can be abraded, rubbed off or torn off during operation.

Description

7599H 1

Name of the invention

Sensor arrangement with setting aid Description

FIELD OF THE INVENTION The invention relates to a sensor for attachment to a carrier or a static roller bearing part, wherein a signal sensor contained in the sensor is provided for detecting a signal of a signal transmitter movable relative to the signal receiver. Furthermore, the invention relates to a sensor arrangement with such a sensor and a roller bearing unit with such a sensor arrangement.

State of the art

Background of the invention

Rolling bearing sensors are used to obtain information about the rolling bearing, which allows statements about the type of operation (eg rotational speed, measurement of the static and dynamic force) or about the functional state of the rolling bearing (end-of-life sensing). There are a number of applications for such sensors, which are usually high-tech products, which usually have to be monitored for safety reasons (eg speed sensors for anti-lock systems in motor vehicles). For a secure operation, a secure attachment is mandatory, since a change in the sensor position on the detection signal in a non-reconstructible manner and thus the meaningfulness of the signal is lost or at least influenced. 7599H 2

A safe and accurate positioning requires a large installation effort in the attachment of the sensor or in the manufacture of the sensor assembly. Therefore, there have been efforts to make the fastening device simple to save manufacturing costs, but this must be compatible with a secure and stable attachment.

From US 5,640,087A a sensor for an angular contact ball bearing with fastening device is known in which the sensor is fixed in a fixed flange on the journal. The housing of the sensor has a resilient in the radial direction spring element with a latching lug. This locking lug is provided for locking in a groove in the carrier, which determines the axial position of the sensor. Snapping in detects that the sensor is in the correct position. Thereafter, a substantially disk-shaped fastening element which is in axial positive engagement with the sensor is fastened by means of a screw on the fixed flange.

Task summary of the invention

The object of the invention is therefore the positioning of the sensor in a carrier or a stationary rolling bearing as inexpensively as possible, but also safe and easy to design.

The object is achieved by a wheel bearing unit of the type mentioned above, that in the detection direction from the signal sensor to the signal generator an adjustment on the sensor is fixed. According to the invention, the sensor is provided for attachment to a carrier or a static rolling bearing part. The carrier can in this case hold the function of keeping or receiving the rolling bearing, such as a wheel carrier receives a wheel bearing. This makes a silent 7599H 3 stationary wheel carrier excellent to record a sensor, for example, for the direction of rotational speeds. This can be for example in a cylindrical bore or another recess. Alternatively, the sensor may also be fixed in a static rolling bearing part, such as a part of the sealing arrangement, a stationary bearing ring, another ring, such as a fastening ring, circlip or sealing ring. These components have the property pertaining to the non-rotating part of the rolling bearing, ie in particular not to possibly multi-part running hub. It is important that it is a static component, which in the immediate vicinity of the signal generator, such as an encoder, in particular a Multipole- coder is arranged. A signal sensor contained in the sensor is provided for detecting a signal of the signal transmitter movable relative to the signal sensor. The signal generator is provided with a rotating component, that is, with a component of the hub. The signal generator can be designed as a so-called window scorer, which has punched holes in the signaling area. Since the flow-guiding properties of the holes differ from the solid material, a coding results. The signal generator can also be designed as a multipole encoder having alternating magnetic north and south poles in the circumferential direction. The movement of these magnetic poles induces an induction current in the signal sensor contained in the sensor. This can be an active or passive sensor. In a passive sensor, the induction current is generated only by movement of the alternating magnetic fields, wherein in an active sensor, the magnetic field changes are increased by the fact that a magnetic field is produced by the signal sensor itself. The changes of this magnetic field by the Multipolencoder cause a much larger signal current than with passive sensors. 7599H 4

According to the invention, an adjustment aid on the sensor, on the signal sensor and / or on a roller bearing part is fixed in the detection direction from the signal sensor to the signal generator. The adjustment aid is intended to be mountable within the rolling bearing, so that the position of the adjustment aid forms a stop for the sensor against which the sensor abuts during the installation process. The setting aid fulfills the function of the distance between the signal generator and the signal sensor, as long as the sensor is not yet attached to the stationary rolling bearing part or the carrier. For example, it is possible for the setting aid to be positionable on a ring of the sealing arrangement by means of a radial positive locking. The adjustment aid is thus an element which only ensures during the installation process that the correct position of the sensor or of the signal sensor is achieved when carrying out an installation movement of the sensor. The position is then held by the provided attachment mechanism.

The installation process consists in first attaching the adjustment aid and then moving the sensor within its support so that it abuts the adjustment aid. Upon impact, the adjustment aid is in a frictional connection between the sensor and another component, such as a sensor. the signal transmitter, the sealing ring or another component which allows a reliable distance between signal generator and signal sensor.

In an advantageous embodiment, the adjustment aid for starting the sensor can be removed from a frictional connection between the sensor and the signal generator without changing the detection distance between the sensor and the signal generator. After positioning the sensor, there is less clearance to remove the adjustment aid. The removal takes place in an axially aligned detection direction advantageously in the radial direction or in the circumferential direction relative to the axis of rotation of the rolling bearing, in a radial detection direction advantageously in the axial direction or circumferential direction. When the adjustment aid is removed, it is made from a frictional connection between the sensor and another component, in particular the signal 7599H 5 selector, removed. The attachment of the setting on the roller bearing must support this removal with the appropriate clearance, so that a fixing of the adjustment is prevented. Alternatively, the adjustment is non-positively, positively or materially fixed to the sensor. It is advantageous that the setting aid at the beginning of the installation of the sensor does not have to be fixed or positioned in a separate installation step, but is used or arranged together with the sensor. The adjustment aid can be snapped onto the sensor, for example. It is also conceivable a simple plug-in mechanism or other positive connection, which optionally supports cost-effective assembly of the sensors.

A material fit of a setting aid fastened to the sensor can consist, for example, of a plastic which has been produced together with a plastic housing of the sensor in the same injection process, or has been vulcanized onto the housing.

A frictional connection can be achieved, for example, by gluing with an adhesive that holds the setting aid to the sensor. The frictional connection can also be brought about by bonding with or without an adhesive. A heating of the adjustment aid to be fastened could lead to an attachment even without adhesive in the appropriately selected material. For example, paper pulp may be glued as adjustment aid similar to a paper seal. Also, a soft plastic is conceivable, such as an epoxy or silicone compound. Due to the bonding, the attachment of the adjustment aid on the sensor is greatly simplified.

In an advantageous embodiment, the adjustment aid is a layer, a covering or a structurally independent spacer. Since the adjustment aid is provided for maintaining a distance, it is advantageously sufficient to provide this as a layer on the detection-side end of the sensor. Thus, the cost of materials would be minimal, without the function of the adjustment aid in question 7599H 6. A layer is an applied material which has a minimal extent in the detection direction. A layer is structurally not independent, because due to the small extent in one direction on the structural stability of the sensor, or its housing, is used. Nevertheless, the layer has a certain stability, which, however, is directed perpendicular to the detection direction or the installation direction.

In contrast, a coating does not have its own stability, but rather its ability to absorb forces solely by the support on the sensor. However, the flooring is a cost effective alternative. For example, if the lining is made of a lubricant, e.g. a grease, which advantageously at the temperature during the installation of the sensor has a solid state of aggregation, but at a subsequent use by the higher operating temperature of the bearing melts and henceforth acts as a lubricant.

Advantageously, the adjustment can also be a structurally independent object in the form of a spacer. By structurally independent, it is meant that the spacer need not be connected to the sensor to maintain its shape. Nevertheless, this spacer is moored to the sensor so that it can accomplish a distance attitude, which takes place in larger dimensions, as with a covering or a layer. The spacer may, for example, be a spacer, which has a direction of detection between 1 to 4 mm. With a covering or a layer, distances of less than 2 mm are advantageous.

In an advantageous embodiment, at least one measure of the adjustment aid is selected as a function of a sensor property. This may be the extension of the adjustment aid along the detection direction, which determines the signal strength of the non-contact transmission between the signal generator and the signal sensor. Alternatively, the adjustment aid can be used as a magnetic flux 7599H 7 conductive element may be executed, which possibly amplifies the magnetic flux or advantageously bundles.

In an advantageous embodiment, the extent of the setting aid in the detection direction predetermines the detection distance to the signal transmitter which is suitable for the sensor. Thus the adjustment aid can be adapted to a sensor type or type of signal generator. Alternatively, with a given sensor arrangement, a variation of the setting aid is conceivable in order to generate a product variety with different product characteristics, whereby a smaller component variety (it is only necessary to vary the extent of the setting aid) is achieved despite high product variation.

In an advantageous embodiment, the adjustment is provided during sensor operation to remain on the sensor and the material abrasion by the sig- nal encoder, the adjustment provided for grinding or tearing by the signal generator from the adhesion with the adjustment out. For this purpose, the adjustment of an abradable or tearable material, which is sufficiently amorphous, or soft, to allow the removal without much effort. For example, silicon compound is suitable for tearing off and an epoxy resin is suitable for abrading. The signal generator creates its own rotational freedom by sufficiently rubbing off the setting aid, or by slightly reducing the extent of the setting aid in the detection direction, so that the frictional connection between the signal generator and the setting aid is canceled. Alternatively, the free grinding can be at least partially taken over by another rotatable component of the wheel hub, whereby the not always solid signal generator is supported.

In an advantageous embodiment, the adjustment aid is provided for remaining on the sensor during the sensor operation and is displaceable by the signal transmitter on the sensor. For example, the signal generator is a perforated plate or an encoder with an extension that can move the adjustment on an inclined surface in an axial or radial direction. In order to 7599H 8, the setting aid is removed from the rotary area of the signal transmitter. It makes sense to provide a rail or other guide means on the sensor, which supports the unlocking movement of the adjustment. Alternatively, the adjustment can also be a positive connection with another rotatable component, which has a defined distance from the signal generator. In this case, this rotatable component, such as a sealing ring, as a circlip or a bearing ring or similar component, the function of the signal generator and creates a rotation clearance by a material removal on the setting.

Advantageously, the adjustment aid is made integral with the housing or a housing part of the sensor. This consists adjustment and the housing of the same material. Basically, a material is chosen for the housing of the sensor, which optimally supports the abrasion, but nevertheless effectively protects the sensor against environmental influences, such as water or dirt particles. The material here is a plastic.

Advantageously, a sensor arrangement with an adjusting aid according to the invention comprises further components, such as a sealing ring, various sealing lips or sealing gaps. It is quite advantageous if the free ground distance between the sensor and signal generator also forms a sealing gap at the same time, which optionally forms part of a non-contact pre-seal.

In an advantageous embodiment, the signal generator on a rotatable rolling bearing part of a rolling bearing unit, in particular wheel bearing unit, fixed. The rotatable rolling bearing part are components of the hub, such as a rotatable inner ring, a support ring of a seal assembly or a flange, such as a wheel flange of a wheel bearing unit. 7599H 9

Further advantageous embodiments and preferred developments of the invention can be taken from the description of the figures and / or the dependent claims. In the following, the invention will be described and explained in more detail with reference to the exemplary embodiments illustrated in the FIGURE.

Exemplary embodiment of the drawings

Fig. 1 shows a sensor arrangement according to the invention of a not shown wheel bearing, wherein an adjustment aid 6 between the sensor 2 and the signal generator 4 is positively clamped. The coded part 5 of the signal generator 4 is aligned axially with respect to the axis of rotation of the wheel bearing to the signal sensor 7 of the sensor 2, the signal sensor 7 is arranged at the detection end of the sensor 2 under the surface of the axial boundary surfaces of the sensor 2. The sensor 2 is inserted during installation in a bore of the fixed wheel carrier 3 with the detection-side end first. Alternatively, the fixed wheel carrier 3 may also be a stationary axle journal. The adjusting aid 6 forms a stop for the sensor 2 in the axial direction, whereby the sensor 2 can be optimally positioned before it is detected with the screw 1 within the bore of the wheel carrier 3. From the finding, the adjustment aid 6 is no longer needed, since the optimum detection distance is already ensured by the attachment of the sensor 2 by the screw 1 permanently. The adjustment aid 6 is intended to be removed in the radial direction on the frictional connection between the signal transmitter 4 and the sensor 2. Advantageously, the adjustment aid 6 to the signal generator 4 towards magnetic or has a magnet, so that the adjustment aid 6 before positioning the 7599H 10

Sensor 2 is held by magnetic force to the coded part 5 in position. Since both the adjustment aid 6, as well as the signal generator 4 have axial interfaces, the removal of the adjusting 6 in the radial direction is nothing in the way.

Alternatively, the adjustment aid 6 is attached to the sensor 2 before installation, for example, glued or latched to the sensor 2. In this case, the adjustment aid 6 must also fit through the bore of the wheel carrier 3, which in the radial and circumferential directions ideally has similar external dimensions as the sensor 2. In this alternative, the adjustment aid 6 remains disposed during operation of the sensor assembly in this even after the screw 1 has been detected. The signal generator 4 is provided to the operation of the wheel bearing to create their own space by the signal generator 4 removes material from the setting 6. This can be achieved particularly simply if the signal generator 4 is a cold-formed corrugated metal sheet, or has special elements for removal, such as, for example, edges or beads. The detection takes place from the signal generator 4 by the adjustment aid 6 to the signal sensor 7. Another alternative embodiment would be an adjustment aid which is guided by the sensor through a groove or rail and is pushed back by the encoder. During installation, the sensor is inserted and fastened with the setting aid. A (not shown) nose of the adjustment is located in a punched out hole of the encoder. Once the encoder is rotated, the adjustment aid slides back along the rails on the sensor to remain there, or is pushed down by the sensor and permanently disconnected. The permanent separation is more advantageous because it can not lead to the blocking of the encoder. In summary, the invention relates to a sensor for attachment to a carrier or a static roller bearing part, wherein a signal sensor contained in the sensor is provided for detecting a signal of a signal transducer movable relative to the signal sensor. It should teach a lesson 7599H 1 1 how the positioning of the sensor within the carrier or static rolling bearing part can be made cost-effective, simple and safe. It is proposed in the detection direction from the sensor to the signal generator to attach a setting aid on the sensor, on the signal generator or another static rolling bearing part, wherein the adjustment aid is subsequently removable without affecting the detection distance between the sensor and signal generator or the adjustment is intended to remain on the sensor, wherein the frictional connection between the setting aid and signal generator is canceled by the operation of the rolling bearing.

7599H 12

LIST OF REFERENCE NUMBERS

1 screw

2 sensor

3 wheel carriers

4 signalers

5 Coded part

6 Setting aid

7 signal receivers

Claims

7599H claims

1 . Sensor (2) for attachment to a carrier or a static Wälzla- gerteil (3), wherein in the sensor (2) containing Signalaufnehmer (7) for detecting a signal of a relative to the Signalaufnehmer (7) movable signal generator (4) provided characterized in that in the detection direction from the signal receiver (7) to the signal generator an adjustment aid (6) on the sensor, on the signal sensor (7) and / or on a roller bearing part is fixed.

2. Sensor (2) according to claim 1, wherein the adjustment aid (6) non-positively, positively or materially connected to the sensor (2) is fixed.

3. Sensor (2) according to claim 2, wherein the adjustment aid (6) is a layer, a loading or a structurally independent spacer.

4. Sensor (2) according to one of the preceding claims, wherein at least one measure of the adjustment aid (6) is selected as a function of a sensor property.

5. sensor (2) according to claim 4, wherein the extension of the adjusting aid (6) in the detection direction for the sensor (2) suitable detection distance to the signal generator (4) pretends.

6. Sensor (2) according to any one of the preceding claims, wherein the adjustment aid (6) during the sensor operation for remaining on the sensor (2) and the material abrasion by the signal generator (4) is provided, wherein the adjustment aid (6) for free grinding by the Signal transmitter (4) from the frictional connection with the setting aid (6) is provided out.

7. Sensor according to one of the preceding claims 1 to 5, wherein the adjustment aid is provided during the sensor operation to remain on the sensor and the adjustment aid is displaceable by the signal generator on the sensor 7599H

8. Sensor (2) according to any one of the preceding claims, wherein the adjustment aid (6) integral with a housing or a housing part of the sensor (2) is executed.

9. Sensor (2) according to claim 1, wherein the adjustment aid (6) for starting the sensor (2) from a frictional connection between the sensor (2) and the signal generator (7) is removable, without the detection distance between the sensor (2) and the To change the signal generator (4).

10. Sensor arrangement with a signal transmitter (4) and a sensor (2) according to one of claims 1 to 8.

1 1. Rolling bearing unit, in particular wheel bearing unit, with a sensor arrangement according to claim 9, wherein the signal generator (4) is fixed on a rotatable rolling bearing part of the rolling bearing unit.