JP5042946B2 - Working angle sensor for constant velocity universal joint - Google Patents

Description

  The present invention relates to an operation angle sensor for a constant velocity universal joint that is mounted on a constant velocity universal joint in an automobile, an industrial machine, or the like and detects an operation angle of the constant velocity universal joint.

In automobiles and industrial machines, a constant velocity universal joint is used as one of devices for coupling a driving device and a driven part. In such constant velocity universal joints, various structures with improved durability have been proposed (for example, Patent Document 1).
JP-A-9-177814

However, in the constant velocity universal joint, when the operating angle increases, the ball transmits a driving force using a portion having a thin outer ring wall thickness, which promotes material fatigue of the outer ring. If the allowable operating angle is exceeded, contact between the inner ring shaft and the outer ring or dropout of the ball may occur.
Therefore, it was considered to constantly monitor the operating angle of the constant velocity universal joint during operation. If this operating angle can always be detected, it is possible to prevent an accident caused by contact between the inner ring shaft and the outer ring, ball dropout, or breakage by stopping the device before the operating angle reaches the allowable upper limit value.
However, the constant velocity universal joint rotates as a whole, and the inner ring and the outer ring generate an operating angle. Therefore, it is difficult to detect the operating angle during operation, and sensors that can detect the operating angle during such operation are not available. There is no example in the past.

  An object of the present invention is to provide an operation angle sensor for a constant velocity universal joint capable of detecting an operation angle of the constant velocity universal joint in operation.

The working angle sensor for a constant velocity universal joint according to the first aspect of the present invention has a track groove formed on the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, and a ball is incorporated between the outer ring track groove and the inner ring track groove. An operating angle sensor provided in a constant velocity universal joint having an inner ring shaft provided with a cage for holding the ball and having the inner ring attached to an outer periphery or integrally formed with the inner ring,
A convex spherical surface portion provided on an end surface of the inner ring shaft and concentric with a rotation center of the inner ring shaft with respect to the outer ring, a concave spherical surface portion provided on an inner surface of the outer ring and facing the convex spherical surface portion through a gap, and the concave portion A circumferential groove provided concentrically with the axis of the outer ring on the spherical surface, a magnetism generating coil provided in the circumference groove, and driving the magnetism generating coil with an electric current having an AC component, And a detection circuit for detecting an inductance change of the coil for generating magnetism from the relationship between the current and the voltage to obtain an operating angle between the inner ring and the outer ring.
The magnetic field generated by the magnetism generating coil driven by a current having an alternating current component becomes a closed magnetic field with the central part and the peripheral part of the concave spherical part in the outer ring as magnetic poles and via the convex spherical part of the inner ring axis. . Since the area of the opposing spherical surface and convex spherical surface of the opposing spherical surface portion changes according to the operating angle, the magnetic path cross-sectional area of the magnetic field changes, and this change is a change in magnetoresistance, that is, a magnetism generating coil. Appears as a change in inductance. As a result, the amplitude of the alternating voltage applied to the magnetism generating coil also changes, and the phase shift between the voltage and current also changes. From the relationship between the current and voltage, the detection circuit detects the operating angle of the constant velocity universal joint.
As described above, according to the operating angle sensor for the constant velocity universal joint, the operating angle of the constant velocity universal joint during operation can always be monitored. For this reason, it is possible to estimate the life of the constant velocity universal joint by monitoring the operating angle together with the driving force and the operating time, and it is possible to prevent an accident due to breakage. Further, an alarm is issued before the detected operating angle reaches the allowable upper limit value, and the device using the constant velocity universal joint is stopped, thereby preventing the contact between the inner ring shaft and the outer ring and the falling of the ball.

A working angle sensor for a constant velocity universal joint according to a second aspect of the present invention is the first aspect of the present invention, wherein the magnetism generating coil and the circumferential groove are provided on the inner ring shaft side instead of on the outer ring side.
That is, a concave spherical surface portion that is provided on the inner surface of the outer ring and faces the convex spherical surface portion through a gap, a circumferential groove that is provided concentrically with the axial center of the inner ring shaft on the convex spherical surface portion, and the circumferential groove The magnetism generating coil provided in the motor and the magnetism generating coil are driven by a current having an AC component, and a change in inductance of the magnetism generating coil is detected from the relationship between the current and the voltage to detect the inner ring and the outer ring. And a detection circuit for obtaining an operating angle between the two.
Also in this configuration, the operating angle of the constant velocity universal joint in operation can be detected by the same action as the operation angle sensor for the constant velocity universal joint of the first invention.

In the first and second aspects of the present invention, the convex spherical surface and the concave spherical surface are opposed to each other in a state where the operating angle is zero, and when the operating angle is generated, the convex spherical portion and the concave spherical surface portion are shifted from each other to generate a non-opposing portion. Also good.
As described above, when the operating angle is generated between the convex spherical surface portion and the concave spherical surface portion, they are shifted from each other to form a non-opposing portion, so that it is easy to detect the operating angle based on a change in magnetic resistance.

  The convex spherical surface portion and the concave spherical surface portion may be configured such that at least a part thereof faces in a state where the outer ring and the inner ring have a maximum operating angle. Even when the inner and outer rings have the maximum operating angle, the operating angle can be reliably detected by the change in magnetic resistance. Even when the inner and outer rings have the maximum operating angle, the operating angle can be reliably detected by the change in magnetic resistance. Therefore, the range in which the operating angle of the constant velocity universal joint during operation can be monitored can be increased, and the life of the constant velocity universal joint can be more accurately estimated.

  A shaft head may be provided at an end portion of the inner ring shaft, and the convex spherical portion of the inner ring shaft may be provided at the shaft head. In this invention, the shaft head may be an enlarged shaft head having a larger diameter than the inner ring shaft. In this case, even if the inner and outer rings have the maximum operating angle, the outer peripheral portion of the convex spherical portion of the enlarged-diameter shaft head and the concave spherical portion can face each other. Therefore, the operating angle can be reliably detected by the change in the magnetic resistance. Thus, it is possible to increase the range in which the operating angle of the constant velocity universal joint in operation can be monitored, and to estimate the life of the constant velocity universal joint more accurately.

  The outer diameter of the concave spherical portion provided on the inner surface of the outer ring may be larger than the outer diameter of the inner ring shaft. In this case, the allowable upper limit value of the operating angle between the inner ring and the outer ring can be increased. That is, the range in which the operating angle of the constant velocity universal joint during operation can be monitored can be increased, and the life of the constant velocity universal joint can be more accurately estimated. Further, when a circumferential groove is provided in the concave spherical portion and a magnetism generating coil is provided in the circumferential groove, the number of turns of the coil can be increased, and the detection sensitivity can be increased.

  The working angle sensor for a constant velocity universal joint according to a third aspect of the present invention has a track groove formed on the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, and a ball is incorporated between the outer ring track groove and the inner ring track groove. A working angle sensor provided in a constant velocity universal joint having an inner ring shaft provided with a cage for holding the ball and having the inner ring attached to an outer periphery or integrally formed with the inner ring, A diameter-expanding shaft head member having a larger diameter than the inner ring shaft, wherein one surface of the diameter-expanding shaft head member forms a convex spherical surface concentric with the rotation center of the cage with respect to the outer ring. A member, a concave spherical portion provided on the inner surface of the outer ring and facing the convex spherical surface via a gap, a circumferential groove provided concentrically with the axis of the outer ring on the concave spherical portion, and the circumferential groove The magnetism generating coil provided inside the magnet And a detection circuit for driving the coil for current with an alternating current component, detecting a change in inductance of the coil for generating magnetism from the relationship between the current and voltage, and obtaining an operating angle between the inner ring and the outer ring. Features.

The operating angle sensor for a constant velocity universal joint according to a third aspect of the present invention is the first aspect of the present invention, wherein instead of providing a convex spherical surface portion on the end face of the inner ring shaft, a diameter expansion shaft head member is provided in the cage. One surface of the head member is a convex spherical surface. In this case, since the diameter-expanded shaft head member can be easily manufactured, for example, by press working or the like, the manufacturing cost can be reduced as compared with the case where the end surface of the inner ring shaft is processed to be spherical. In addition, since the diameter-enlarged shaft head member is provided in the cage having a diameter larger than that of the inner ring shaft, even if the inner and outer rings have the maximum operating angle, a part of the convex spherical surface of the diameter-enlarged shaft head member, It becomes possible to face the concave spherical portion. Therefore, the operating angle can be reliably detected by the change in the magnetic resistance.
Other operations and effects similar to those of the first invention are provided.

  In the constant velocity universal joint according to the first aspect of the present invention, a track groove is formed on each of the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, and a ball is incorporated between the outer ring track groove and the inner ring track groove. An operating angle sensor provided on a constant velocity universal joint having an inner ring shaft attached to an outer periphery or integrally formed with the inner ring, the cage being provided on an end surface of the inner ring shaft. A convex spherical surface concentric with the center of rotation of the inner ring shaft with respect to the outer ring, a concave spherical portion provided on the inner surface of the outer ring and facing the convex spherical portion via a gap, and an axial center of the outer ring on the concave spherical portion And a magnetic generating coil provided in the circumferential groove, and the magnetic generating coil are driven by a current having an AC component, and the relationship between the current and the voltage is Inner coil for magnetism generation Since provided with a detection circuit for obtaining an operating angle between the inner ring and the outer ring by detecting a change in inductance, it is possible to detect the operating angle of the constant velocity universal joint during operation.

  A constant velocity universal joint according to a second aspect of the present invention includes a circumferential groove provided concentrically with the axial center of the inner ring shaft in the convex spherical surface portion, and a magnetism generating coil provided in the circumferential groove. And a detection circuit for driving the magnetism generating coil with a current having an AC component, and detecting a change in inductance of the magnetism generating coil based on a relationship between the current and the voltage to obtain an operating angle between the inner ring and the outer ring. Therefore, the operating angle of the constant velocity universal joint during operation can be detected.

  A constant velocity universal joint according to a third aspect of the present invention is an enlarged shaft head member that is provided at an end of the cage and has a larger diameter than the inner ring shaft, and one surface of the enlarged shaft head member is A diameter-enlarged shaft head member having a convex spherical surface concentric with the center of rotation of the cage with respect to the outer ring, a concave spherical surface provided on the inner surface of the outer ring and facing the convex spherical surface through a gap, A circumferential groove provided concentrically with the axis of the outer ring, a magnetism generating coil provided in the circumference groove, and the magnetism generating coil are driven by a current having an AC component, Since it has a detection circuit for detecting the change in inductance of the coil for generating magnetism based on the voltage relationship and obtaining the operating angle between the inner ring and the outer ring, the operating angle of the constant velocity universal joint during operation can be detected. .

An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view showing a part of a constant velocity universal joint 1 equipped with an operating angle sensor 11 according to this embodiment. The constant velocity universal joint 1 is a fixed type and includes an outer ring 2, an inner ring 3, an inner ring shaft 4, a ball 5 that is a rolling element for torque transmission, and a cage 6 that holds the ball 5.
The outer ring 2 has a cup part 2a and a stem part 2b. The inner surface of the cup portion 2a of the outer ring 2 has a spherical shape on the opening side inner surface portion of the opening side inner surface portion and the bottom side inner surface portion. Six (or eight) track grooves 7 are formed in the spherical inner surface 2aa along the axial direction. The outer surface of the inner ring 3 is spherical, and six (or eight) track grooves 8 are formed along the axial direction on the spherical outer surface 3aa. The outer ring track grooves 7 and the inner ring track grooves 8 face each other, and the balls 5 are incorporated between the track grooves 7 and 8 facing each other. The cage 6 is a member that holds the balls 5 in the same plane, and the balls 5 are held in pockets 6a provided at a plurality of locations in the circumferential direction.
The inner ring 3 includes a central hole 9 having an uneven portion such as a serration or a spline on the inner periphery, and one end portion of the inner ring shaft 4 is fitted in the central hole 9 so that torque can be transmitted. The inner ring shaft 4 may be formed integrally with the inner ring 3.

An end surface of the inner ring shaft 4 that faces the inner surface of the outer ring cup portion 2a is a convex spherical portion 12 that is a convex spherical surface that is concentric with the rotation center O of the inner ring shaft 4 with respect to the outer ring cup portion 2a. Further, a convex portion 13 having a circular end surface shape is provided at the center of the bottom side inner surface portion of the inner surface of the outer ring cup portion 2a, and the tip surface of the convex portion 13 passes through the convex spherical portion 12 of the inner ring shaft 4 via a gap. The concave spherical surface portion 13a faces the concave spherical surface.
The convex spherical surface portion 12 and the concave spherical surface portion 13a face each other with the operating angle shown in FIG. 2 (B) being zero, and in the state where the operating angle is generated as shown in FIG. 2 (A). The non-opposing portions are provided so as to be shifted from each other.

The concave spherical surface portion 13a of the outer ring 2 is provided with a circumferential groove 14 concentrically with the axis O1 of the outer ring 2, and a magnetism generating coil 15 serving as a sensor element of the operating angle sensor 11 is provided in the circumferential groove 14. Is provided. Both the outer ring 2 and the inner ring shaft 4 are made of steel or the like, and are made of a ferromagnetic material. The concave spherical surface portion 13a of the outer ring 2 and the vicinity of the convex spherical surface portion 12 of the inner ring shaft 4 are formed by a magnetism generating coil 15. It becomes the magnetic path of the generated magnetic field. A gap between the convex spherical portion 12 and the concave spherical portion 13a becomes a magnetic gap.
Outside the constant velocity universal joint 1, the magnetism generating coil 15 is driven by a current having an AC component having a constant amplitude, and a change in inductance of the magnetism generating coil 15 is detected from the relationship between the current and the voltage. In addition, a detection circuit 16 for obtaining an operating angle between the inner ring 3 and the outer ring 2 is provided.

The detection circuit 16 includes a rotation-side electronic circuit 17 provided on the outer periphery of the cup portion 2a of the outer ring 2, and a stationary-side electronic circuit 19 provided away from the constant velocity universal joint. The stationary electronic circuit 19 may be a circuit independently configured on a circuit board or the like, or may be a circuit provided in an automobile ECU (electric control unit) or the like.
Relay between the rotation-side electronic circuit 17 and the stationary-side electronic circuit 19 is performed by a non-contact electromagnetic coupling 18. The non-contact electromagnetic coupling 18 includes a rotating side coil 18a wound around the outer surface of the outer ring cup portion 2a concentrically with the axis of the outer ring 2, and a fixed coil installed concentrically with the coil 18a on the outer periphery of the coil 18a. It consists of the side coil 18b. The fixed side coil 18b is a coil for power transmission / signal reception, and the rotation side coil 18a is a coil for power reception / signal transmission.
The operating angle sensor 11 is configured by the convex spherical surface portion 12, the concave spherical surface portion 13a, the magnetism generating coil 15, the detection circuit 16, the non-contact electromagnetic coupling 18, and the like.

  The rotation-side electronic circuit 17 of the detection circuit 16 is connected to the magnetism generating coil 15 by wiring, and the wiring is inserted into a through hole (not shown) provided in the outer ring 2 or the cup portion 2 a of the outer ring 2. It is provided along the inner surface of the cup part 2a from the opening part.

The rotation-side electronic circuit 17 uses the electric power sent from the stationary-side electronic circuit 19 via the non-contact electromagnetic coupling 18 as a power source, drives the magnetism generating coil 15 with a current having an AC component having a constant amplitude, and magnetically This is a circuit that performs processing to send the output signal of the generating coil 15 to the stationary electronic circuit 19 via the non-contact electromagnetic coupling 18. The rotation-side electronic circuit 17 includes a frequency discriminating circuit (FM detection circuit) for the current sent from the stationary-side electronic circuit 19, a rectifying circuit for rectifying the discriminated current, and the rectified direct current to provide the constant amplitude. A sensor drive circuit that generates a current having an AC component and applies the current to the magnetism generating coil 15, a modulation circuit that modulates an output signal detected from the magnetism generating coil 15, and the non-contact electromagnetic coupling 18 And a low-power excitation circuit (not shown) that enables transmission via the network.
The stationary electronic circuit 19 includes a high power excitation circuit that performs excitation for supplying power to the stationary electronic circuit 19 via the non-contact electromagnetic coupling 18, and a non-contact electromagnetic coupling 18 from the rotation-side electronic circuit 17. A frequency discriminating circuit for frequency discriminating the modulated signal sent via the signal, and a demodulating circuit (none of which is shown) for demodulating the discriminated signal.

  Next, the operation of the operation angle sensor 11 for the constant velocity universal joint will be described. A current having an AC line segment having a constant amplitude is applied to the magnetism generating coil 15 from the rotation-side electronic circuit 17 in the detection circuit 16. As a result, a magnetic field is generated in the magnetism generating coil 15, and this magnetic field is closed by passing through the convex spherical part 12 of the inner ring shaft 4 with the central part and the peripheral part of the concave spherical part 13a in the outer ring cup part 2a as magnetic poles. Magnetic field. The area of the opposing spherical surface portion 13a and convex spherical surface portion 12 facing each other changes according to the operating angle. That is, the concave spherical surface portion 13a and the convex spherical surface portion 12 have the maximum facing area when the operating angle is zero degrees, and the facing area decreases as the operating angle increases. As a result, the change in operating angle appears as a change in magnetic resistance, that is, as an inductance change in the magnetism generating coil 15. That is, as the operating angle increases, the magnetic resistance also increases. As the magnetic resistance increases, the inductance of the magnetism generating coil 15 decreases, the amplitude of the AC voltage applied to the coil 15 also decreases, and the phase shift between the voltage and current also decreases. The relationship between the current and the voltage is transmitted from the rotation-side electronic circuit 17 to the stationary-side electronic circuit 19 via the non-contact electromagnetic coupling 18. The stationary electronic circuit 19 detects the operating angle of the constant velocity universal joint 1 by calculating the inductance change of the magnetism generating coil 15 from the relationship between the current and the voltage.

  As described above, according to the operation angle sensor 11 for the constant velocity universal joint, the operation angle of the constant velocity universal joint 1 in operation can always be monitored. Therefore, by monitoring the operation angle together with the driving force and the operation time, The life of the universal joint 1 can be estimated and accidents due to breakage can be prevented in advance. Further, an alarm is issued before the detected operating angle reaches the allowable upper limit value, and the device using the constant velocity universal joint 1 is stopped, thereby preventing the contact between the inner ring shaft 4 and the outer ring 2 and the falling of the ball 5 in advance. be able to.

  FIG. 3 shows another embodiment of the present invention. In the embodiment of FIG. 1, the constant angle universal joint operating angle sensor 11 is provided with a circumferential groove 14A concentric with the axis O2 of the inner ring shaft 4 on the convex spherical surface portion 12 of the inner ring shaft 4, and this circumferential groove 14A. A magnetism generating coil 15 is provided therein. Although not shown, the rotation-side electronic circuit 17 in FIG. 1 and the rotation-side coil 18 a of the non-contact electromagnetic coupling 18 are provided on the outer peripheral surface of the inner ring shaft 4. Other configurations are the same as those in the embodiment of FIG.

  Also in this embodiment, the magnetic field generated by the magnetism generating coil 15 passes through the concave spherical surface portion 13a of the outer ring cup portion 2a with the central portion and the peripheral portion of the convex spherical surface portion 12 of the inner ring shaft 4 as magnetic poles. The areas of the opposing spherical surface portion 12 and concave spherical surface portion 13a that face each other change according to the operating angle. Other functions and effects are the same as those in the embodiment of FIG.

  FIG. 4 is a partially broken front view of a constant velocity universal joint equipped with an operating angle sensor according to still another embodiment of the present invention. In the present embodiment, on the inner surface of the outer ring cup portion 2 a, the outer diameter Da of the concave spherical surface portion 13 a on the tip surface of the convex portion 13 is larger than the outer diameter Db of the inner ring shaft 4. In this case, the convex spherical surface portion 12 and the concave spherical surface portion 13a are exposed at the outer peripheral edge portion 13aa of the concave spherical surface portion 13a with the operating angle shown in FIG. That is, the remaining portion of the concave spherical surface portion 13a excluding the outer peripheral edge portion 13aa and the entire surface of the convex spherical surface portion 12 face each other. Further, in the state where the maximum operating angle is taken, at least a part of the convex spherical surface portion 12 and the concave spherical surface portion 13a face each other. Although not shown, the outer diameter Da of the concave spherical surface portion 13a is determined so that the concave spherical surface portion 13a and the cage 6 do not interfere with each other at the allowable upper limit value of the operating angle. Other configurations are the same as those in the embodiment of FIG.

  In this embodiment, since the outer diameter Da of the concave spherical portion 13a is larger than the outer diameter Db of the inner ring shaft 4, the allowable upper limit value of the operating angle between the inner ring 3 and the outer ring 2 can be increased. That is, the range in which the operating angle of the constant velocity universal joint during operation can be monitored can be increased, and the life of the constant velocity universal joint can be more accurately estimated. In addition, the diameter of the circumferential groove 14 of the concave spherical surface portion 13a can be increased to increase the number of turns of the magnetism generating coil 15 in the circumferential groove 14, and the detection sensitivity can be increased. In addition, the same operations and effects as the embodiment of FIG.

Still another embodiment of the present invention will be described with reference to FIG.
In this embodiment, a shaft head JT is provided at one end of the inner ring shaft 4, and the surface of the shaft head JT is formed as a convex curved surface 12. The shaft head JT has a curved main body 12a that forms a convex curved surface 12, and an engaging portion 12b that is attached to the outer peripheral edge of the curved main body 12a. The engaging portion 12 b protrudes a predetermined small distance parallel to the axis of the inner ring shaft 4 and is engaged with an engaged portion 4 a that is an annular groove formed at one end of the inner ring shaft 4.

  Further, the shaft head portion JT is, for example, a thin plate, and the curved body 12a and the engaging portion 12b can be integrally formed by pressing or the like. However, it is not limited only to press work. The engagement portion 12b formed along the circumferential direction is temporarily expanded radially outward by elastic deformation or the like, and can be engaged with the engaged portion 4a of the inner ring shaft 4. Note that a fixing tool such as a bolt may be used as a method of fixing the shaft head JT to the inner ring shaft 4. According to such a shaft head JT, it is possible to reduce the manufacturing cost as compared with a case where a convex spherical surface is processed on the end surface of the inner ring shaft 4. Further, since the existing inner ring shaft 4 can be applied, the mass production effect can be enhanced accordingly. In addition, the configuration is the same as that of the embodiment of FIG. 1, and the same operations and effects as those of the embodiment are achieved.

Still another embodiment of the present invention will be described with reference to FIG.
In this embodiment, an enlarged-diameter shaft head KJ having a larger diameter than the inner ring shaft 4 is provided at one end of the inner ring shaft 4. A convex spherical surface portion KJa is provided on the end surface of the diameter-expanded shaft head portion KJ, and the convex spherical surface portion KJa is formed concentrically with the rotation center of the inner ring shaft 4 with respect to the outer ring 2.
Further, on the inner surface of the outer ring cup portion 2a of the outer ring 2, the outer diameter Da of the concave spherical surface portion 13a of the tip surface of the convex portion 13 is set to the same diameter as the outer diameter Dc of the convex spherical surface portion KJa. In the present embodiment, the concave spherical surface portion 13a of the convex portion 13 is formed separately from the outer ring cup portion 2a, and is fixed to the inner surface of the outer ring cup portion 2a. However, the concave spherical surface portion 13a of the convex portion 13 may be integrally formed on the inner surface of the outer ring cup portion 2a by forging.

  The convex spherical surface portion KJa and the concave spherical surface portion 13a are in a state where the operating angle is zero as shown in FIG. 6B, and the entire surface of the convex spherical surface portion KJa and the entire surface of the concave spherical surface portion 13a are spaced apart from each other. Face to face. As shown in FIG. 6A, at least a part of the convex spherical surface portion KJa and the concave spherical surface portion 13a face each other in a state where the maximum operating angle is taken. Further, the outer diameter Dc of the convex spherical surface portion KJa is determined so that the convex spherical surface portion KJa and the cage 6 do not interfere when the operating angle is the allowable upper limit value. Further, in any state where the operating angle is taken, the axial protrusion amount δJ and the outer diameter of the convex spherical portion KJa are prevented so that the convex spherical portion KJa of the enlarged-diameter shaft head KJ does not interfere with the inner surface of the outer ring cup portion 2a. Dc is defined. Other configurations are the same as those in the embodiment of FIG.

  According to the embodiment shown in FIG. 6 described above, since the enlarged shaft head KJ having a diameter larger than that of the inner ring shaft 4 is provided at one end of the inner ring shaft 4, the inner and outer rings have the maximum operating angle. Even so, the outer peripheral portion of the convex spherical surface portion KJa in the shaft diameter shaft head portion KJ and the concave spherical surface portion 13a can face each other. Therefore, the operating angle can be reliably detected by the change in the magnetic resistance. Thus, it is possible to increase the range in which the operating angle of the constant velocity universal joint in operation can be monitored, and to estimate the life of the constant velocity universal joint more accurately.

  When the concave spherical surface portion 13a of the convex portion 13 is formed separately from the outer ring cup portion 2a, an assembly in which the magnetism generating coil 15 is provided in the circumferential groove 14 of the concave spherical surface portion 13a is replaced with an outer ring cup. It can be easily fixed to the inner surface of the portion 2a. In this case, on the inner surface of the outer ring cup portion 2a, the assembly can be simplified and the number of work steps can be reduced as compared with the case where the magnetism generating coil 15 is wound in the circumferential groove 14. When the concave spherical surface portion 13a of the convex portion 13 is integrally formed on the inner surface of the outer ring cup portion 2a by forging, the overall number of parts can be reduced and the structure can be simplified. In addition, the same effects as the embodiment of FIG.

Still another embodiment of the present invention will be described with reference to FIGS.
In the present embodiment, an enlarged shaft head member KB having a diameter larger than that of the inner ring shaft 4 is provided at one end of the cage 6, and one surface of the enlarged shaft head member KB is rotated with respect to the outer ring 2 of the cage 6. A convex spherical surface 12KB substantially concentric with the center is formed. This diameter-expanding shaft head member KB includes a spherical main body 12A that forms a convex spherical surface 12KB, and an engaging portion 12B that is attached to the outer peripheral edge of the spherical main body 12A. The engaging portion 12B protrudes a predetermined small distance toward the outside of the cage 6 in the radial direction, and is formed in an annular step portion 6b formed on the inner periphery of one end portion of the cage 6.

  Further, the diameter-expanded shaft head member KB is, for example, a thin plate shape, and the spherical body 12A and the engaging portion 12B can be integrally formed by pressing or the like. However, it is not limited to press working. The top portion 12Aa of the spherical body 12A faces the concave spherical portion 13a in a state where the operating angle is zero. A plurality of through holes 12Ah are formed at regular intervals in the circumferential direction in the outer peripheral portion 12Ab excluding the top portion 12Aa of the spherical body 12A. Therefore, based on the change of the magnetic resistance according to the facing area where the remaining top portion 12Aa excluding these through-holes 12Ah and the concave spherical surface portion 13a of the spherical body 12A face each other, the same as in the embodiment of FIG. The operating angle of the quick universal joint 1 can be detected.

  As shown in FIG. 8A, at least a part of the top portion 12Aa and the concave spherical portion 13a of the spherical main body 12A face each other in a state where the maximum operating angle is taken. Further, the dimension of the spherical main body 12A or the inner surface dimension of the outer ring cup portion 2a is defined so that the diameter-expanded shaft head member KB and the inner surface of the outer ring cup portion 2a do not interfere with each other at any operating angle. . Furthermore, these dimensions are defined so that the enlarged diameter head member KB and the inner ring 3 or the inner ring shaft 4 do not interfere with each other at any operating angle. The other configuration is the same as that of the embodiment of FIG.

  According to the embodiment described above, instead of providing the convex spherical portion on the end face of the inner ring shaft, the cage 6 is provided with the enlarged diameter head member KB, and one surface of the enlarged diameter head member KB is formed as the convex spherical surface 12KB. is there. In this case, since the diameter-expanded shaft head member KB can be easily manufactured, for example, by pressing or the like, the manufacturing cost can be reduced as compared with the case where the end surface of the inner ring shaft is spherically processed.

In particular, since the diameter-expanded shaft head member KB is provided in the cage 6 having a diameter larger than that of the inner ring shaft 4, a part of the convex spherical surface 12KB of the diameter-expanded shaft head member KB is obtained even when the maximum operating angle is taken. That is, the top portion 12Aa and the concave spherical surface portion 13a can face each other. Therefore, the operating angle can be reliably detected by the change in the magnetic resistance. Further, since the plurality of through holes 12Ah are formed in the outer peripheral portion 12Ab of the spherical main body 12A, the diameter-expanded shaft head member KB can be reduced in weight, and the constant velocity universal joint 1 can be reduced in weight. In addition, the same effects as the embodiment of FIG.
In the present embodiment, a plurality of through holes 12Ah are formed in the outer peripheral portion 12Ab of the spherical main body 12A, but a portion made of a nonmagnetic material may be provided in the outer peripheral portion 12Ab instead of each through hole. In this case, it is possible to increase the rigidity of the diameter-expanded shaft head member KB.

It is a partially broken front view of the constant velocity universal joint equipped with the operating angle sensor concerning one Embodiment of this invention. (A) is a partially broken front view showing a state where the equivalent velocity universal joint has an operating angle, and (B) is a partially broken front view showing a state where the operating angle is zero degrees. (A) is a partially broken front view of a constant velocity universal joint equipped with an operating angle sensor according to another embodiment of the present invention, and (B) is a partially broken front view showing a state of zero operating angle. It is a partially broken front view of the constant velocity universal joint equipped with the operating angle sensor concerning further another embodiment of this invention. (A) is a partially broken front view of a constant velocity universal joint equipped with an operating angle sensor according to still another embodiment of the present invention, and (B) is a partially broken front view showing a state of zero operating angle. (A) is a partially broken front view of a constant velocity universal joint equipped with an operating angle sensor according to still another embodiment of the present invention, and (B) is a partially broken front view showing a state of zero operating angle. (A) is a partially broken front view of a constant velocity universal joint equipped with an operating angle sensor according to still another embodiment of the present invention, and (B) is a partially broken front view showing a state of zero operating angle. (A) It is sectional drawing which expands and represents the principal part of FIG. 7 (A), (B) It is sectional drawing which expands and represents the principal part of FIG. 7 (B).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Constant velocity universal joint 2 ... Outer ring 3 ... Inner ring 4 ... Inner ring shaft 5 ... Ball 11 ... Operating angle sensor 12 ... Convex spherical surface part 12KB ... Convex spherical surface part 13a ... Concave spherical surface part 14, 14A ... Circumferential groove 15 ... For magnetic generation Coil 16 ... detection circuit 17 ... rotation side electronic circuit 18 ... non-contact electromagnetic coupling 19 ... stationary side electronic circuit JT ... shaft head KJ ... shaft diameter shaft head KJa ... convex spherical surface KB ... expanded diameter head member

Claims (8)

A track groove is formed on each of the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, a ball is incorporated between the outer ring track groove and the inner ring track groove, a cage for holding the ball is provided, and the inner ring is attached to the outer periphery or An operating angle sensor provided in a constant velocity universal joint having an inner ring shaft formed integrally with the inner ring,
A convex spherical surface portion provided on an end surface of the inner ring shaft and concentric with a rotation center of the inner ring shaft with respect to the outer ring, a concave spherical surface portion provided on an inner surface of the outer ring and facing the convex spherical surface portion through a gap, and the concave portion A circumferential groove provided concentrically with the axis of the outer ring on the spherical surface, a magnetism generating coil provided in the circumference groove, and driving the magnetism generating coil with an electric current having an AC component, An operating angle sensor for a constant velocity universal joint, comprising: a detection circuit that detects a change in inductance of the coil for generating magnetism based on a relationship between the current and voltage to obtain an operating angle between the inner ring and the outer ring. A track groove is formed on each of the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, a ball is incorporated between the outer ring track groove and the inner ring track groove, a cage for holding the ball is provided, and the inner ring is attached to the outer periphery or An operating angle sensor provided in a constant velocity universal joint having an inner ring shaft formed integrally with the inner ring,
A convex spherical surface portion provided on an end surface of the inner ring shaft and concentric with a rotation center of the inner ring shaft with respect to the outer ring; a concave spherical surface portion provided on an inner surface of the outer ring and facing the convex spherical surface portion through a gap; A circumferential groove provided concentrically with the axis of the inner ring shaft on the spherical surface, a magnetism generating coil provided in the circumference groove, and the magnetism generating coil are driven by a current having an AC component. An operation angle sensor for a constant velocity universal joint, comprising: a detection circuit that detects a change in inductance of the magnetism generating coil based on a relationship between the current and voltage and obtains an operation angle between the inner ring and the outer ring.   3. The first and second convex surface portions and the concave spherical surface portion according to claim 1, wherein the entire surface of the convex spherical surface portion and the concave spherical surface portion face each other when the operating angle is zero, and when the operating angle is generated, the convex spherical portion and the concave spherical surface portion are displaced from each other to generate a non-opposing portion. Working angle sensor for joints.   4. The constant velocity according to claim 1, wherein at least a part of the convex spherical surface portion and the concave spherical surface portion face each other in a state where the outer ring and the inner ring have a maximum operating angle. Operating angle sensor for universal joints.   5. The operation for a constant velocity universal joint according to claim 1, wherein a shaft head is provided at an end of the inner ring shaft, and the convex spherical portion of the inner ring shaft is provided at the shaft head. Angular sensor.   6. The operating angle sensor for a constant velocity universal joint according to claim 5, wherein the shaft head is an enlarged shaft head having a larger diameter than the inner ring shaft.   The operating angle for a constant velocity universal joint according to any one of claims 1 to 6, wherein an outer diameter of the concave spherical surface portion provided on an inner surface of the outer ring is larger than an outer diameter of the inner ring shaft. Sensor. A track groove is formed on each of the spherical inner surface of the outer ring and the spherical outer surface of the inner ring, a ball is incorporated between the outer ring track groove and the inner ring track groove, a cage for holding the ball is provided, and the inner ring is attached to the outer periphery or An operating angle sensor provided in a constant velocity universal joint having an inner ring shaft formed integrally with the inner ring,
An enlarged shaft head member provided at an end of the cage and having a diameter larger than that of the inner ring shaft, wherein one surface of the enlarged shaft head member has a convex spherical surface concentric with a rotation center with respect to the outer ring of the cage. An enlarged diameter head member,
A concave spherical surface provided on the inner surface of the outer ring and facing the convex spherical surface through a gap;
A circumferential groove provided concentrically with the axis of the outer ring in the concave spherical surface portion;
A magnetism generating coil provided in the circumferential groove;
A detection circuit that drives the magnetism generating coil with a current having an AC component, detects a change in inductance of the magnetism generating coil from the relationship between the current and voltage, and obtains an operating angle between the inner ring and the outer ring;
An operation angle sensor for a constant velocity universal joint.

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