GB2043256A - Rotation sensor - Google Patents

Abstract

A sensor (17) for monitoring speed or angular velocity of a half-shaft (5) comprises a rod-like magnetic stator (13) and a toothed pulsing wheel (11). The toothed wheel is carried by the half-shaft (5) of a differential and the rod-like stator (13) is inserted radially into the housing (7) of the half-shaft from the outside. The toothed wheel can either be a sleeve on the half-shaft or formed integrally therewith. <IMAGE>

Description

SPECIFICATION Sensor The invention relates to sensors for monitoring speed or angular velocity in a vehicle, e.g. for an anti-skid system.

A sensor having a magnetic stator and a toothed pulsing wheel is known (German Offenlegungsschrift No. 2 154 448). It is advantageous to fit the sensor in the region of the half-shaft as no extreme temperatures occur there. The known sensor has a toothed wheel which is fixed on a sleeve which encircles the half-shaft, whilst the stator is fixed to the axle tube by way of a plurality of intermediate members. The sleeve is cumbersome and requires an additional bearing, and the stator needs many parts and great expense to be fixed.

The present invention provides a sensor for monitoring speed or angular velocity which comprises a toothed pulsing wheel or a half-shaft on the differential of a mechanically propelled vehicle and a rod-like magnetic stator radially inserted into a housing which accommodates the half-shaft.

By comparison with the above mentioned prior art, the sensor of the invention has the advantage that the toothed wheel can be placed upon the half-shaft directly and simply. It can thereby by produced as a separate part, but it is also possible to produce the toothed wheel integrally with the halfshaft. The rod-like stator which is inserted radially into the housing which accommodates the half-shaft can be fixed directly there without any further components.

The half-shaft is generally provided with a multispline toothing. The half-shaft itself is guided thereby.

An appropriately large gap can be provided between stator and rotor to take into account any side blows to which the half-shaft might be subjected.

Because of the special installation feature, it is not necessary to reset said gap even after a long travel time.

The invention is further described, by way of example, with reference to the drawings, in which Figure 1 is a plan view of a vehicle axle with a differential; Figure 2 is a sectional view showing a sensor incorporated in a half-shaft; and Figure 3 is a fragmentary detail view of a modification to the half-shaft.

A motor vehicle, which is not shown fully, has a rear axle 1 which is driven by way of a differential 2.

A housing 3 of the differential 2 has on each side an opening 4 (Figure 2) which is covered by an annular seal 4' and through which a splined end 6 of a half-shaft 5 extends.

The other end of the half-shaft 5 extends outwardlythrough a substantially cylindrical axle housing or tube 7 where it is connected to a vehicle wheel in a manner which is not shown. A chamber 10, which is separated from the differential 2 by the annular seal 4' is formed in the axle housing 7 between a surface 8 of the half-shaft 5 and an inside wall 9 of the axle housing 7.

On its surface 8, the half-shaft 5 carries a toothing 11 which forms a pulsing wheel. The pulsing wheel 11 may either be directly produced integrally with the half-shaft 5 or, as shown in Figure 3, be in the form of a thin-walled cylindrical hollow body 12 and be drawn onto the surface 8 of the half-shaft 5. In the latter case, spreadable tabs should be provided in a simple manner on the hollow body 12 to connect the hollow body 12 rigidly to the half-shaft 5.

A rod-like stator 13 is inserted radially into the axle housing 7 which accommodates the half-shaft 5. A gap 18, which can be bridged by magnetic forces, is formed between the end face of the stator 13 and the pulsing wheel 11. The stator 13 is fixed axially and is fitted with an O-ring seal. Its outer end is covered by a cap 15 which also contains an electrical line connection 16 for connecting the sensor 17, compris ing the pulsing wheel 11 and the stator 13, to an electronic control mechanism (not shown), input information being supplied to the control mechanism by way of the line connection 16. The control mechanism can, for example, be an anti-skid system of the vehicle.

The wheel speed or the angular velocity is directly sensed at the half-shaft 5 of the vehicle. A sensor of this kind offers a considerable reduction in outlay compared with conventional sensors, particularly for commercial vehicles. The assembly of the sensor 17 is simple, it is not subjected to any extreme temperatures and the gap 18 does not need to be reset. Its installation is particularly suitable for massproduction because of these advantages.

1. A sensor for monitoring speed or angular velocity which comprises a toothed pulsing wheel or a half-shaft on the differential of a mechanically propelled vehicle and a rod-like magnetic stator radially inserted into a housing which accommodates the half-shaft.

2. A sensor according to claim 1, in which the toothed wheel is located directly on the surface of the half-shaft.

3. A sensor according to claim 2, in which the toothed wheel comprises a cylindrical hollow body and is rigidly attached to the half-shaft.

4. A sensor according to claim 3 in which the cylindrical body is attached to the half shaft by spreadable tabs.

5. A sensor according to claim 1, in which the toothed wheel is formed integrally with the halfshaft.

6. A sensor for monitoring speed or angular velocity constructed and arranged substantially as herein described with reference to and as illustrated in the drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Sensor The invention relates to sensors for monitoring speed or angular velocity in a vehicle, e.g. for an anti-skid system. A sensor having a magnetic stator and a toothed pulsing wheel is known (German Offenlegungsschrift No. 2 154 448). It is advantageous to fit the sensor in the region of the half-shaft as no extreme temperatures occur there. The known sensor has a toothed wheel which is fixed on a sleeve which encircles the half-shaft, whilst the stator is fixed to the axle tube by way of a plurality of intermediate members. The sleeve is cumbersome and requires an additional bearing, and the stator needs many parts and great expense to be fixed. The present invention provides a sensor for monitoring speed or angular velocity which comprises a toothed pulsing wheel or a half-shaft on the differential of a mechanically propelled vehicle and a rod-like magnetic stator radially inserted into a housing which accommodates the half-shaft. By comparison with the above mentioned prior art, the sensor of the invention has the advantage that the toothed wheel can be placed upon the half-shaft directly and simply. It can thereby by produced as a separate part, but it is also possible to produce the toothed wheel integrally with the halfshaft. The rod-like stator which is inserted radially into the housing which accommodates the half-shaft can be fixed directly there without any further components. The half-shaft is generally provided with a multispline toothing. The half-shaft itself is guided thereby. An appropriately large gap can be provided between stator and rotor to take into account any side blows to which the half-shaft might be subjected. Because of the special installation feature, it is not necessary to reset said gap even after a long travel time. The invention is further described, by way of example, with reference to the drawings, in which Figure 1 is a plan view of a vehicle axle with a differential; Figure 2 is a sectional view showing a sensor incorporated in a half-shaft; and Figure 3 is a fragmentary detail view of a modification to the half-shaft. A motor vehicle, which is not shown fully, has a rear axle 1 which is driven by way of a differential 2. A housing 3 of the differential 2 has on each side an opening 4 (Figure 2) which is covered by an annular seal 4' and through which a splined end 6 of a half-shaft 5 extends. The other end of the half-shaft 5 extends outwardlythrough a substantially cylindrical axle housing or tube 7 where it is connected to a vehicle wheel in a manner which is not shown. A chamber 10, which is separated from the differential 2 by the annular seal 4' is formed in the axle housing 7 between a surface 8 of the half-shaft 5 and an inside wall 9 of the axle housing 7. On its surface 8, the half-shaft 5 carries a toothing 11 which forms a pulsing wheel. The pulsing wheel 11 may either be directly produced integrally with the half-shaft 5 or, as shown in Figure 3, be in the form of a thin-walled cylindrical hollow body 12 and be drawn onto the surface 8 of the half-shaft 5. In the latter case, spreadable tabs should be provided in a simple manner on the hollow body 12 to connect the hollow body 12 rigidly to the half-shaft 5. A rod-like stator 13 is inserted radially into the axle housing 7 which accommodates the half-shaft 5. A gap 18, which can be bridged by magnetic forces, is formed between the end face of the stator 13 and the pulsing wheel 11. The stator 13 is fixed axially and is fitted with an O-ring seal. Its outer end is covered by a cap 15 which also contains an electrical line connection 16 for connecting the sensor 17, compris ing the pulsing wheel 11 and the stator 13, to an electronic control mechanism (not shown), input information being supplied to the control mechanism by way of the line connection 16. The control mechanism can, for example, be an anti-skid system of the vehicle. The wheel speed or the angular velocity is directly sensed at the half-shaft 5 of the vehicle. A sensor of this kind offers a considerable reduction in outlay compared with conventional sensors, particularly for commercial vehicles. The assembly of the sensor 17 is simple, it is not subjected to any extreme temperatures and the gap 18 does not need to be reset. Its installation is particularly suitable for massproduction because of these advantages. CLAIMS

1. A sensor for monitoring speed or angular velocity which comprises a toothed pulsing wheel or a half-shaft on the differential of a mechanically propelled vehicle and a rod-like magnetic stator radially inserted into a housing which accommodates the half-shaft.

2. A sensor according to claim 1, in which the toothed wheel is located directly on the surface of the half-shaft.

3. A sensor according to claim 2, in which the toothed wheel comprises a cylindrical hollow body and is rigidly attached to the half-shaft.

4. A sensor according to claim 3 in which the cylindrical body is attached to the half shaft by spreadable tabs.

5. A sensor according to claim 1, in which the toothed wheel is formed integrally with the halfshaft.

6. A sensor for monitoring speed or angular velocity constructed and arranged substantially as herein described with reference to and as illustrated in the drawings.