| WO/2000/055646 | ACCELEROMETER TRANSDUCER USED FOR SEISMIC RECORDING |
| JP2009075052 | ROTATION DETECTION SENSOR |
| JP05340963 | ACCELERATION SIGNAL GENERATOR |
CHEVE, Olivier (11 Chemin de la Bondonnière, Chanceaux S/Choisille, F-37390, FR)
LANDRIEVE, Franck (La Butte, Fondettes, F-37230, FR)
CHEVE, Olivier (11 Chemin de la Bondonnière, Chanceaux S/Choisille, F-37390, FR)
| CLAIMS 1. Rolling bearing assembly (1 ; 101), in particular for a two-wheeled vehicle, comprising: - a rolling bearing (5 ; 105) having an inner ring (7 ; 107), an outer ring (8 ; 108) and rolling elements (9 ; 109), a target unit (10 ; 110) comprising a target (11 ; 111) rotatable around a rotation axis (Χ105-ΧΊ05) of the rolling bearing (5 ; 105), the target unit (10 ; 110) being fast in rotation with the outer ring (8 ; 108), - a sensor unit (6 ; 106) holding at least one sensing element (13 ; 113), the sensor unit (6 ; 106) being fast in rotation with the inner ring (7 ; 107), the sensing element (13 ; 113) being arranged to read the target (11 ; 111), the sensing element (13 ; 113) being intended to enable generation of output signals representative of at least one rotational parameter of the rolling bearing, a shaft component (14 ; 114) arranged to support the rolling bearing (5 ; 105), the shaft component (14 ; 114) being fast in rotation with the inner ring (7 ; 107), at least one output conductor (15 ; 115), connected to the sensing element (13 ; 113) for conveying the output signals, wherein: the outer surface (16 ; 116) of the shaft component (14 ; 114) has a connection groove (17; 117) which is located substantially between the inner ring (7; 107) and the rotation axis (X5-X5 ; Χ105-ΧΊ05), along a direction (Y5-Y5 ; Υ105-ΥΊ05) perpendicular to the rotation axis (Xs-X's ; Χ105-ΧΊ05), the or each output conductor (15 ; 115) passes through the connection groove (17 ; 117), the connection groove (17 ; 117) has an external end (18 ; 118) which is located opposite the sensing element (13 ; 113) relative to the rolling bearing (5 ; 105) and which is open on a terminal surface (39; 139) of the shaft component (14 ; 114). 2. Rolling bearing assembly (1 ; 101) according to claim 1, wherein the connection groove (17 ; 117) extends substantially parallel to the rotation axis 3. Rolling bearing assembly (1 ; 101) according to any preceding claim, wherein the external end (18 ; 118) is flush with the external axial face (21 ; 121 ) of the inner ring (7 ; 107) along an axial direction parallel to the rotation axis 4. Rolling bearing assembly (1) according to any preceding claim, wherein the outer diameter (D10) of the target unit (10) is larger than the outer diameter (D6) of the sensor unit (6). 5. Rolling bearing assembly (1 ) according to claim 4, wherein the outer diameter (D10) of the target unit (10) approximately equals the outer diameter (D8) of the outer ring (8). 6. Rolling bearing assembly (1) according to claim 4 or 5, wherein the target unit (10) and the outer ring (8) are in planar contact. 7. Rolling bearing assembly (101) according to any of claims 1 to 5, wherein the target unit (110) is fastened to the rolling bearing (105). 8. Rolling bearing assembly (1 ; 101) according to any preceding claim, wherein the target (11 ; 111) faces the sensing element (13 ; 113) along a direction parallel to the rotation axis (Xs-X's ; Xios-X'-ios)- 9. Rolling bearing assembly (1 ; 101) according to any preceding claim, wherein the output conductor (15 ; 115) and the sensing element (13 ; 113) are overmoulded in a body (19 ; 119) of the sensor unit (6 ; 106), the body (19 ; 119) being made of an electrically insulating material, the output conductor (15 ; 115) extending in a leg (20 ; 120) of the body (19; 119). 10. Rolling bearing assembly (1 ; 101) according to claim 9, wherein the leg (20 ; 120) and the connection groove (17 ; 117) have corresponding widths (W20, W17) along a tangential direction (Z5-Z'5), so that the leg (20 ; 120) fastens the sensor unit (6 ; 106) in rotation with the shaft component (14 ; 114). 11. Rolling bearing assembly according to any preceding claim, wherein the shaft component forms a shaft for the rolling bearing assembly. 12. Rolling bearing assembly (1 ; 101) according to any preceding claim, wherein the shaft component (14 ; 114) is separate from a shaft (4 ; 104) of the rolling bearing assembly (1 ; 101 ), the shaft component (14 ; 114) being fixed relative to the shaft (4 ; 104). 13. Rolling bearing assembly (1 ; 101) according to any preceding claim, wherein the shaft component (14 ; 114) has a shoulder (26 ; 126) for stopping the sensor unit (6 ; 106) in translation along the shaft component (14 ; 114). 14. Rolling bearing assembly (101) according to any preceding claim, wherein the rolling bearing assembly (101) further comprises a connecting terminal (134) located at the external end (118) for connection to an input connector (133). 15. Spacer (130), for holding at a determined distance from a support member a rolling bearing assembly (101) according to any preceding claim, the spacer (130) having a substantially cylindrical shape, the spacer (130) being arranged to be fast in rotation with the shaft component (114), wherein the spacer (130) comprises an input connector (133) arranged for connection with the output conductor (115) for collecting the output signals. 16. Spacer (130) according to claim 15, wherein the input connector (133) is fixedly secured to the spacer (130). 17. Spacer (130) according to claim 16, wherein the input connector (133) is arranged to cooperate with the output conductor (1 15) along a direction parallel to the rotation axis (Xios-X'-ios)- 18. Spacer (130) according to claim 17, wherein the input connector (133) is located at the external end (1 18), along a direction parallel to the rotation axis 19. Spacer (130) according to any of claims 1 5 to 18, wherein the spacer (1 30) has a ring portion (1 31 ) projecting outwards for abutment against the external axial face (121 ) of the inner ring (107) which lies opposite the sensing element (1 13). 20. Spacer (1 30) accord ing to claim 1 9, wherein the ring portion (131 ) comprises a sealing element, such as an O-ring, arranged to press against said external axial face (121 ). 21 . Spacer according to any of claims 15 to 20, wherein the spacer further comprises means for wireless transmission of the output signals. 22. Spacer (130) according to any of claims 1 5 to 21 , wherein the spacer (130) has at least one cylindrical projection (136) protruding from an axial face (1 37) of the spacer ( 1 30), the cylindrical projection (136) being intended to cooperate with a corresponding cylindrical recess (138) so as to enhance coaxial alignment between the spacer (130) and the rolling bearing assembly (101 ). 23. Spacer (130) according to any of claims 1 5 to 22, wherein the spacer (130) further has locking means (139) for locking in rotation the spacer (130) and the shaft component (1 14). 24. Spacer ( 1 30 ) accord ing to cla im 23, wherein the locking means comprise a hole (139) for receiving a key (140) protruding parallel to the rotation axis (Χ105-ΧΊ05) so as to enter a corresponding bore (141) of the shaft component (114). 25. Method for assembling a rolling bearing assembly (1 ; 101 ) according to any of claims 1 to 14 onto a rotating body (19 ; 119) having a shaft (4 ; 104) and a hub (2 ; 102), like a wheel, wherein the method comprises the steps of: a) securing the shaft component (14 ; 114) to the shaft (4 ; 104); b) putting the sensor unit (6 ; 106) on the shaft component (14 ; 114); c) placing the or each output conductor (15 ; 115) inside the connection groove (17; 117), so that the output conductor (15; 115) reaches the external end (18 ; 118); d) positioning the target unit (10 ; 110); e) fitting the rolling bearing (5; 105), with the outer ring (8; 108) fast in rotation to the hub (2 ; 102) and the inner ring (7 ; 107) fast in rotation to the shaft component (14 ; 114), so that the sensing element (13; 113) can read the target (11 ; 111). 26. Method according to claim 24, wherein the method further comprises the step of: f) moving a spacer (130) according to any of claims 15 to 23 parallel to the rotation axis (Χ105-ΧΊ05) up to the connection between the output conductor (115) and the input connector (133). |
ASSEMBLING SUCH A ROLLING BEARING ASSEMBLY AND SUCH A
SPACER
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rolling bearing assembly. The present invention also relates to a spacer intended to determine the position of such a rolling bearing assembly. Besides, the present invention relates to a method for assembling such a rolling bearing assembly and such a spacer. The present invention can be used for example in a wheel of a two-wheeled vehicle, such as a motorcycle or a bicycle.
BACKGROUND ART OF THE INVENTION
A prior art rolling bearing assembly usually has a rolling bearing comprising an outer ring, an inner ring fast in rotation with a shaft and a target fast in rotation with the outer ring. Such a rolling bearing assembly also has a sensor arranged to read the target so as to enable the generation of electric output signals. An output cable is connected to the sensor for driving the output signals up to an electronic control unit. A wheel of a two-wheeled vehicle usually comprises two or more rolling bearing assemblies with their outer rings fastened into a hub. The sensor, the target and the output cable are located on the axial external face of one of the rolling bearings with respect to the hub. Hence, the output cable is located on the same side of the rolling bearing than the target and the sensor.
However, at such a location the target and the sensor are relatively exposed to exterior contaminants. Moreover, mounting the sensor plus the target on the axial external face of the rolling bearing is relatively cumbersome, hence reduces the axial compactness of a rotating body usually including such a rolling bearing assembly. Besides, such an output cable is often submitted to different mechanical strains which risk to damage it or even to disconnect it. SUMMARY OF THE INVENTION
One object of the present invention is to overcome the afore-mentioned drawbacks, by providing a compact rolling bearing assembly which enhances the sealing of the target and of the sensor.
To achieve this object, a subject matter of the present invention is a rolling bearing assembly, in particular for a two-wheeled vehicle, comprising:
a rolling bearing having an inner ring, an outer ring and rolling elements, a target unit comprising a target rotatable around a rotation axis of the rolling bearing, the target unit being fast in rotation with the outer ring, a sensor unit holding at least one sensing element, the sensor unit being fast in rotation with the inner ring, the sensing element being arranged to read the target, the sensing element being intended to enable generation of output signals representative of at least one rotational parameter of the rolling bearing,
a shaft component arranged to support the roll ing bearing, the shaft component being fast in rotation with the inner ring,
at least one output conductor, connected to the sensing element for conveying the output signals,
wherein:
the outer surface of the shaft component has a connection groove which is located substantially between the inner ring and the rotation axis, along a direction perpendicular to the rotation axis,
the or each output conductor passes through the connection groove, the connection groove has an external end which is located opposite the sensing element relative to the rolling bearing and wh ich is open on a terminal surface of the shaft component.
In other words, the output conductor is inserted between the inner ring and the shaft component, thus linking both sides of the rolling bearing: the internal side which is equipped with the target unit and the sensor unit, and the external side which is equipped for instance with an output line leading to an electronic control unit.
According to advantageous but optional features, considered on their own or in any technically feasible combination: - the connection groove extends substantially parallel to the rotation axis ;
- the external end is flush with the external axial face of the inner ring along an axial direction parallel to the rotation axis ;
- the outer diameter of the target unit is larger than the outer diameter of the sensor unit ;
- the outer diameter of the target unit approximately equals the outer diameter of the outer ring ;
- the target unit and the outer ring are in planar contact;
- the target unit is fastened to the rolling bearing;
- the target faces the sensing element along a direction parallel to the rotation axis;
- the output conductor and the sensing element are overmoulded in a body of the sensor unit, the body being made of an electrically insulating material, the output conductor extending in a leg of the body;
- the leg and the connection groove have corresponding widths along a tangential direction, so that the leg fastens the sensor unit in rotation with the shaft component;
- the shaft component forms a shaft for the rolling bearing assembly;
- the shaft component is separate from a shaft of the rolling bearing assembly, the shaft component being fixed relative to the shaft;
- the shaft component has a shoulder for stopping the sensor unit in translation along the shaft component;
- the rolling bearing assembly further comprises a connecting terminal located at the external end for connection to an input connector; Furthermore, another object of the present invention is to provide a spacer, which reduces the mechanical strains applied to the electrical line.
To achieve this object, a subject matter of the present invention is a spacer, for holding at a determined distance from a support member, such as the fork of a two-wheeled vehicle, a rolling bearing assembly as here-above described. The spacer has a substantially cylindrical shape and is arranged to be fast in rotation with the shaft component, wherein the spacer comprises an input connector arranged for connection with the output conductor for collecting the output signals. In other words, the spacer not only achieves the function of a spacer, but also the function of a connector which is directly connected to the sensor unit.
According to advantageous but optional features, considered on their own or in any technically feasible combination:
- the input connector is fixedly secured to the spacer;
- the input connector is arranged to cooperate with the output conductor along a direction parallel to the rotation axis;
- the input connector is located at the external end, along a direction parallel to the rotation axis;
- the spacer has a ring portion projecting outwards for abutment against the external axial face of the inner ring which lies opposite the sensing element;
- the ring portion comprises a sealing element, such as an O-ring, arranged to press against said external axial face;
- the spacer further comprises means for wireless transmission of the output signals;
- the spacer has at least one cylindrical projection protruding from an axial face of the spacer, the cylindrical projection being intended to cooperate with a corresponding cylindrical recess so as to enhance coaxial alignment between the spacer and the rolling bearing assembly;
- the spacer further has locking means for locking in rotation the spacer and the shaft component;
- the locking means comprise a hole for receiving a key protruding parallel to the rotation axis so as to enter a corresponding bore of the shaft component.
Besides, a subject matter of the present invention is a method for assembling a rolling bearing assembly as here-above described onto a rotating body having a shaft and a hub, like a wheel, wherein the method comprises the steps of:
- securing the shaft component to the shaft;
- putting the sensor unit on the shaft component;
- placing the or each output conductor inside the connection groove, so that the output conductor reaches the external end;
- positioning the target unit; - fitting the rolling bearing, with the outer ring fast in rotation to the hub and the inner ring fast in rotation to the shaft component, so that the sensing element can read the target.
According to an advantageous but optional feature, the method further comprises the step of:
- moving a spacer as here-above described parallel to the rotation axis up to the connection between the output conductor and the input connector.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention and its advantages will be well understood on the basis of the following description, which is given as an illustrative example, without restricting the scope of the invention, and in relation with the annexed drawings among which:
- figure 1 is a perspective view of a hub and a fork of a two-wheeled vehicle, the hub comprising a rolling bearing assembly according to the invention;
- figure 2 is a partial cross-section, at a larger scale and along plane II on figure 1 , of the rolling bearing assembly of figure 1 ;
- figure 3 is a view at a larger scale of detail III on figure 2;
- figure 4 is an exploded perspective view of the rolling bearing assembly according to the invention and its environment;
- figure 5 is an exploded perspective view, at an angle different from figure 4 of the rolling bearing assembly of figure 4 and its environment;
- figure 6 is a partial cross-section, similar to figure 2, of a rolling bearing assembly according to another embodiment of the present invention and of a spacer according to the present invention; and
- figure 7 is a view, at a larger scale, of detail VII on figure 6;
- figure 8 is a partly exploded perspective view of the rolling bearing assembly of figures 6 and 7.
DETAILED DESCRIPTION OF SOME EMBODIMENTS
Figure 1 depicts a rolling bearing assembly 1 according to the invention in its assembled and service state. Rolling bearing assembly 1 is mounted into a hub 2 of a not-shown wheel which is held by a support member or fork 3 and which has a shaft 4. The fork 3 belongs to a two-wheeled vehicle, such as a motorcycle. The assembled state of the rolling bearing assembly 1 as illustrated on figure 1 results from the completion of an assembling method according to the invention, which will be described later on.
Figures 2, 3, 4 and 5 depict the rolling bearing assembly 1 , which comprises a ball bearing 5, a sensor unit 6 and a target unit 10. Ball bearing 5 has an inner ring 7, an outer ring 8 and balls 9 arranged to roll between inner ring 7 and outer ring 8.
Outer ring 8 is fast in rotation with hub 2. Outer ring 8 and hub 2 are intended to rotate around a rotation axis X 5 -X' 5 of ball bearing 5, whereas inner ring 7 and shaft 4 are intended to remain static with respect to fork 3. Inner ring 7 is secured to shaft 4. Inner ring 7 and outer ring 8 respectively form the fixed ring and the mobile ring of ball bearing 5.
Rolling bearing assembly 1 also has a target unit 10 comprising a target 1 1 and a target support 12. Target 1 1 is in the form of an encoder washer. Target 1 1 has a generally rotational symmetry around axis X 5 -X' 5 . Target 1 1 is located approximately at the same radius as balls 109. More precisely, target 1 1 is in the shape of a cylinder coaxial to axis X 5 -X' 5 . Target 1 1 is fastened to target support 12. Target unit 10 is fast in rotation with outer ring 8.
Sensor unit 6 is fast in rotation with inner ring 7. Sensor unit 6 includes a sensing element or sensor 13. Sensor 13 is arranged to detect or "read" target 1 1 along an axial direction. To read target 1 1 , sensor 13 extends approximately at the same position as target 1 1 along an axial direction. Sensor 13 extends only partially around axis X 5 -X' 5 . Sensor 13 hence "faces" a limited area of target 1 1 . Along a radial direction, sensor 13 and target 1 1 are separated by a gap 1 1 - 13 which is less than the maximum sensing distance of sensor 13.
In the present application, the term "axial" refers to a direction parallel to the rotation axis X 5 -X' 5 of bal l bearing 5. The term "rad ial" refers to a direction perpendicular to the rotation axis Xs-X's, like radial direction Y 5 -Y' 5 on figure 2. Conversely, a surface is said to be "axial" or "radial" by reference to a direction which is locally or globally perpendicular to that surface. The term "tangential" refers to a direction which is perpendicular both to the rotation axis X 5 -X' 5 and to a radial direction Y5-V5, like direction Z 5 -Z' 5 on figures 4 and 5.
Target 1 1 can be made of a magnetic material and sensor 13 can perform the magnetic detection of target 1 1 , for instance by detecting the intensity or the variation of a magnetic field generated by target 1 1 . In operation, sensor 1 3 gen erates of output s ig nal s representative of one or several rotational parameter(s) of the rolling bearing 5.
Rolling bearing assembly 1 further comprises a shaft component 14 in the shape of a sleeve surrounding shaft 4, separate from shaft 4 and extending axially on part of the length of shaft 4. This shaft component 14 is fixed relative to the shaft 4. For instance, shaft component 14 can be press-fitted, shrunk, welded or glued onto shaft 4. Shaft component 14 can be made of a metallic material. Shaft component 14 is arranged to support ball bearing 5. Shaft component 14 is fast in rotation with inner ring 7.
Rolling bearing assembly 1 also comprises an output conductor in the form of an output cable 15 which is connected to sensor 13 for driving the output signals generated by sensor 13. In the example of figure 3, output cable 15 and sensor 13 are connected by means of connecting pins 35.
As can be seen on figures 4 and 5, the cylindrical, outer surface 16 of shaft component 14 has a connection groove 17 for housing output cable 15. Connection groove 17 is located generally between inner ring 7 and rotation axis X 5 -X'5, along a radial d irection , l ike direction Ys-Y's- Output cable 1 5 passes through connection groove 17. In other words, connection groove 17 and output cable 15 are located radially between inner ring 7 and shaft component 14.
The connection groove 17 extends substantially parallel to rotation axis X 5 -
X' 5 . Furthermore, connection groove 17 emerges or opens axially on a terminal surface 39 of shaft component 14 and has an external end 18 which lies opposite sensor 13 relative to the rolling bearing 5. In other words, external end 18 and sensor 13 are located on opposite sides of ball bearing 5. The terminal surface 39 has an annular shape which extends radially and which is flush with the axial, external face 21 of inner ring 7.
The adjective "external" refers to an element which is, with respect to the rolling bearing assembly 1 , oriented opposite the hub 8, towards the exterior of hub 8. Conversely, the adjective "internal" refers to an element which is oriented towards hub 8.
As can be seen on figures 3, 4 and 5, the external end 18 is axially open on terminal surface 39 and axially clear of the shaft component 14. In the present application, the term "open" means that the output cable 15 is free to exit connection groove 17, and the term "clear" means that the output cable 15 can exit connection groove 17 at the external end 18 without being hampered by shaft component 14.
The external end 18 is flush with the axial, external face 21 of inner ring 7 along an axial direction. In other words, the shaft component 14 and the inner ring 7 approximately share a plane defining their external faces.
Besides, output cable 15 and sensor 13 are overmoulded in a body 19 of the sensor unit 6. The body 19 is made of an electrically insulating material, for instance PA6.6.
The body 19 has a leg 20 extending axially within connection groove 17 and su rrou nd i ng the part of output cab l e 1 5 lying i n connection groove 17. Furthermore, the leg 20 and the connection groove 17 have corresponding widths W 2 o and W 17 along tangential direction Z 5 -Z' 5 . Thus, the leg 20 acts as a key to fasten the sensor unit 6 in rotation with the shaft component 14.
In the example of figures 2, 3, 4 and 5, the outer diameter D10 of target unit
10 is larger than the outer diameter D6 of sensor unit 6. Thus, target unit 10, in particular target support 12, can be held in place between the internal face 22 of outer ring 8 and a shoulder 23 of hub 2. This permits to mount target unit 10 and ball bearing 5 independently into bore 25 of hub 2. Target support 12 is in planar contact with the internal face 22 of outer ring 8. Moreover, target support 12 holds an O-ring 24 which prevents ingress of exterior contaminants into gap 1 1 - 13.
The outer diameter D10 of target unit 1 0 approximately equals the outer diameter D8 of outer ring 8. This facilitates the mounting of target unit 10 and of ball bearing 5 inside a cylindrical bore 25 of hub 2. The shaft component 14 has a shoulder 26 for stopping the sensor un it 6 in translation along the shaft component 14. A spacer 30 is inserted between fork 3 and rolling bearing assembly 1 . Spacer 30 holds ball bearing 5, in particular outer ring 8, away from fork 3 at a fixed, determined, axial distance.
Spacer 30 has a substantially cylindrical shape. Spacer 30 is arranged to be fast in rotation with the shaft component 14. Spacer 30 has a ring portion 31 which bears against the shaft component 14 and against the external face 21 of inner ring 7.
The ring portion 31 has a notch 32 located in front in the external end 18, hence in front the connection groove 17. Thus, the external portion of output cable 15 passes through the external end 18 and through the notch 31 . The external portion of output cable 15 can be connected to a remote electronic control unit 28 by means of a conducting line 27.
Figures 6, 7 and 8 depict a rolling bearing assembly 101 and a spacer 130 according to a second embodiment of the invention. The description of rolling bearing assembly 1 and of spacer 30 given above with reference to figures 1 , 2, 3, 4 and 5 can be transposed to rolling bearing assembly 101 and to spacer 130 of figures 6, 7 and 8, which are similar thereto, except for the hereafter stated differences. An element of rolling bearing assembly 101 or of spacer 130 that is identical or corresponding to an element of rolling bearing assembly 101 or of spacer 130 is allocated the same reference sign plus 100.
One can thus define a hub 102, a shaft 104, a ball bearing 105, a sensor unit 106, an inner ring 107, an outer ring 108, balls 109, a target unit 1 10, a target 1 1 1 , target support 1 12, a sensor 1 13, a gap 1 1 1 .1 13, a shaft component 1 14, an output cable 1 15, an outer surface 1 16 of shaft component 1 14, a connection groove 1 17, an external end 1 18, a sensor unit body 1 19, a leg 120, an external face 121 of inner ring 107, an internal face 122 of outer ring 108, a shoulder 123 of hub 102, a cylindrical bore 125 of hub 102, an electrical line 127, an electronic control unit 128, a spacer 130 and a ring portion 131 .
Rolling bearing assembly 101 differs from rolling bearing assembly 1 in that the target support 1 12 is made of an annular seal which is fitted into a groove 129 of outer ring and onto which is secured target 1 1 1 . Target unit 1 10 is hence fastened to ball bearing 105. Internal face 122 directly contacts shoulder 123. The outer diameter of target unit 1 10 is smaller than the outer diameter of sensor unit 106. Indeed, the body 1 19 of sensor unit 106 extends up to the hub 102, thus helping to seal the gap 1 1 1 -1 13.
Furthermore, the abutment portion of shaft component 1 14 for stopping sensor unit in translation along shaft component 1 14 has a slightly different shape than the abutment portion 26 of rolling bearing assembly 1 .
Alike spacer 30, spacer 130 has a generally cylindrical shape and it is arranged to be fast in rotation with shaft component 1 14, for instance by press- fitting, by shrinking, by gluing or by welding. Like spacer 30, spacer 130 has a ring portion 131 projecting outwards for abutment against the axial, external face 121 of inner ring 107, i.e. the face which stands opposite sensor 1 13.
Spacer 1 30 differs from spacer 30 in that spacer 1 30 comprises an input connector 133 which is arranged for connection with an output conductor formed by output cabl e 1 1 5 i n order to col lect the output signals generated by sensor 1 13.
The input connector 133 is arranged to cooperate with the output cable 1 15 along a direction parallel to the rotation axis Xio5-X'io5- In the present application, the term "cooperate" means that an electrical connection can occur between two components.
Rolling bearing assembly 101 further comprises a connecting terminal 134, which is also located at the external end 1 18 so as to connect to input connector 1 33. Connecting terminal 1 34 is herein made of a female part, whereas input connector 1 33 is made of a male part. The respective dimensions of input connector 133 and of connecting terminal 134 permit their cooperation.
When spacer 1 30 is in its service position relative to rolling bearing assembly 105, e.g. in its position of figures 6 and 7, input connector 133 is located at the external end 1 18, along a direction parallel to axis Xio5-X'ios- Besides, input connector 133 protrudes from ring portion 131 so as to enter connection groove 1 17. Input connector 133 forms one end of an input cable 135, which forms part of the electrical line 127 leading up to the remote electronic control unit 128.
Input cable 135 is embedded, for instance overmoulded, into spacer 130. Input connector 133 is thus fixedly secured to spacer 130. In the present application, the expression "fixedly secured" means that there is no possible relative motion between the two parts that are fixedly secured. Hence, one part, e.g. the input connector 133, transmits every force of torque to the other part, e.g. the spacer 130. In other words, the mechanical stresses applied on the input connector 133 are relieved by the spacer 130.
Spacer 130 also has a cylindrical projection 136 which protrudes from the axial, internal face 137 of ring portion 1 31 . Cylindrical projection 136 extends upon shaft 1 04. Shaft component 1 1 4 has a cyl ind rical recess 138 with dimensions corresponding to the dimensions of cylindrical projection 136, so that cyl indrical projection 1 36 and cylindrical recess 138 cooperate to enhance coaxial alignment between spacer 1 30 and shaft component 1 14, hence the rolling bearing assembly 101 .
As can be seen on figure 6, spacer 130 further has a hole 139 into which a key 140 is received. Key 140 protrudes with respect to the axial internal face 137 and parallel to axis Xio5-X'io5- Shaft component 1 14 has a bore 141 for receiving the protrud ing end of key 1 40. The position and d imensions of bore 141 respectively correspond to the position of hole 139 and to the dimensions of key 140. Thus, hole 139 and bore 141 both cooperate with key 140 and hence form locking means for locking in rotation spacer 130 and shaft component 1 14.
A signal processing circuit can be included in the body 19 or 1 19 of sensor unit 6 or 106 or, alternatively, in the spacer 130.
According to a not-shown embodiment, the shaft component can be integral with the shaft. Thus, the shaft component itself forms a shaft for the roll ing bearing assembly, unlike shaft component 14 or 1 14 which is independent from shaft 4 or 104.
According to a further not-shown embodiment, the spacer 30 or 1 30 can further comprise means for wireless emission of the output signals, such as an antenna, in lieu of the electrical line 27 or 127. An antenna can thus transmit the output signals to a remote electric control unit.
According to another not-shown embodiment, sensor unit can have several corresponding output conductors, hence shaft component can have more than one connection groove, and spacer can have several corresponding input connectors in the second embodiment. Besides, the external end can terminate in a surface which is not flush, but rather offset, with the axial, external face 21 or 1 21 of the inner ring.
Preferably, the ring portion comprises a not-shown sealing element, like an O-ring, which is arranged to press against the axial, external face of inner ring.
Accord ing to a further not-shown embod iment, the target can face the sensing element along a radial direction.
The invention has been described with balls 9 as rolling elements. However, other rolling elements may be contemplated to implement the present invention, like rollers or needles.
Besides, the target can be discrete instead of symmetric around the rotation
I nstead of a mag netic detection of target 1 1 by sensor 13, the roll ing bearing assembly can comprise a sensing element performing an optical reading of a purposely designed target. Other kinds of transducers may be contemplated to form the sensing element 13, e.g. an optoelectronic transducer.
The invention thus provides a rolling bearing assembly which enhances the seal ing of the target unit and of the sensor unit and which can form a relatively compact structure inside a hub.
Furthermore, a spacer according to the invention also achieves the function of a connector, hence reduces the mechan ical strains appl ied to the electrical l ine, because the electrical conductors are fixedly secured to the body of the spacer.
The assembled state of the roll ing bearing assembly 1 of fig u res 2 to 5 results from the completion of an assembling method according to the invention, which will be hereafter described, first in reference to the embodiment of figures 1 to 5.
Inner ring 7, outer ring 8 and balls 9 are pre-assembled to form ball bearing 5.
Shaft component 1 4 is secured to shaft 4. As can be seen on figures 4 and 5, sensor unit 6 is put on the shaft component 1 4. Sensor u n it 6 can be fastened to shaft component 1 4 either by gl ueing , press-fitting or solely by inserting its leg 20 into the connection groove 17.
The output cable 1 5 is thus placed inside connection groove 1 7, so that the output cable 15 reaches the external end 18. Then, target unit 10 can be positioned relative to sensor unit 6, when held between outer ring 8 and shoulder 23 of hub 2.
An operator fits ball bearing 5 so that sensor 1 3 can read target 1 1 . To achieve the fitting operation, the outer ring 8 is fastened to hub 2 and the inner ring 7 is fastened to the shaft component 14. For instance, outer ring 8 can be press-fitted into the cylindrical bore 25 of hub 2 and inner ring 7 can be slidably inserted or press-fitted onto the outer surface 16 of shaft component 14.
Second, with reference to figures 6 to 8, the afore-described assembling method can be performed with similar steps to make rolling bearing assembly 101 , except for the hereafter described step.
Target unit 1 10 is not separated from ball bearing 105, unlike target unit 10. Hence, the target unit 1 10 is positioned with respect to outer ring 108.
The method for assembl ing the roll ing bearing assembly 101 further comprises a specific step of moving the spacer 130 along axis Χ105-ΧΊ05 up to the connection between the output cable 1 15, i.e. an output connector and the input connector 133. Such a method permits to link spacer 130 according to the invention and a rolling bearing assembly 101 according to the invention.
A method according to the invention permits to easily build a rolling bearing assembly according to the invention, and to equip it with a spacer according to the invention.