JP2006201026A - Rotation angle detection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To heighten detection accuracy of a rotation angle detection apparatus by excluding an influence of backlash of gears. <P>SOLUTION: The rotation angle detection apparatus 11 includes a main pulley 14 provided for the outer circumference of a steering shaft 15; first and second sub-pulleys 20 and 25 connected to the main pulley 14 via a cog belt 28; and first and second rotation angle sensors 18 and 23 for detecting each rotation angle of both sub-pulleys 20 and 25 and detects the rotation angle of the steering shaft 15 on the basis of output of both rotation angle sensors 18 and 23. Since the use of the cog belt 28 eliminates the influence of backlash caused in the case that the main pulley 14 and the first and second sub-pulleys 20 and 25 are interlocked via gears, it is possible to accurately interlock rotation angles of three pulleys 14, 20 and 25 while suppressing the occurrence of noise. The degree of freedom of arrangement of the three pulleys 14, 20 and 25 is improved in comparison with the case that the main pulleys 14 and first and second sub-pulleys 20 and 25 are interlocked via gears. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a main ring provided on the outer periphery of a rotating shaft, a plurality of sub-rings that rotate in conjunction with the rotation of the main ring, and a plurality of rotations that detect rotation angles of the plurality of sub-rings, respectively. The present invention relates to a rotation angle detection device that includes an angle sensor and detects a rotation angle of the shaft based on outputs of the plurality of rotation angle sensors.

A steering angle sensor that detects a rotation angle of a steering shaft based on a change in a magnetic field associated with rotation of a pair of driven gears by meshing a pair of driven gears each having a magnet with an annular drive gear fixed to the steering shaft. This is known from US Pat.
JP 2000-159037 A

  By the way, in the above-mentioned conventional one, the rotation angle of the steering shaft is detected based on the rotation angles of the pair of driven gears meshed with the annular drive gear, so that the steering shaft rotates in the right turning direction and the left turning The rotational angle of the driven gear changes due to the backlash of the gear when rotating in the direction, which causes a problem that the detection accuracy of the rotational angle of the steering shaft is lowered. In addition, there is a problem that the degree of freedom of the position of the pair of driven gears relative to the position of the annular drive gear is limited, and noise is generated due to the influence of gear backlash.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to improve the detection accuracy of a rotation angle detection device by eliminating the influence of gear backlash.

  In order to achieve the above object, according to the first aspect of the present invention, a main ring provided on the outer periphery of the rotating shaft, and a plurality of sub-rings rotating in conjunction with the rotation of the main ring, A rotation angle detecting device that detects a rotation angle of the shaft based on outputs of the plurality of rotation angle sensors, the rotation angle detecting device comprising: a plurality of rotation angle sensors that respectively detect rotation angles of the plurality of sub-annular rings; A rotation angle detecting device is proposed, wherein an endless bell is wound around the ring and the plurality of sub-rings, and the plurality of sub-rings are rotated in conjunction with the rotation of the main ring.

  According to the invention described in claim 2, in addition to the structure of claim 1, in order to generate a predetermined tension on the endless belt, at least one of the plurality of sub-annular rings is biased. A featured rotation angle detection device is proposed.

  According to the invention described in claim 3, in addition to the structure of claim 1 or claim 2, the endless belt is a cog belt that engages with the main ring and the sub ring in an uneven manner. A rotation angle detecting device is proposed.

  The main pulley 14 of the embodiment corresponds to the pulley of the present invention, the steering shaft 15 of the embodiment corresponds to the shaft of the present invention, and the first and second rotation angle sensors 18 and 23 of the embodiment are the same as those of the present invention. Corresponding to the rotation angle sensor, the first and second sub pulleys 20 and 25 of the embodiment correspond to the sub ring of the present invention.

  According to the configuration of claim 1, a plurality of sub-rings that rotate around the rotation of the main ring by winding an endless belt around the main ring and the plurality of sub-rings provided on the outer periphery of the rotating shaft. Since the rotation angle of the shaft is detected by detecting the rotation angle of the shaft, the rotation angle of the shaft is detected. The rotation angle of the main ring can be accurately linked to the rotation angle of the sub-ring while suppressing the occurrence. Moreover, the degree of freedom of layout of the sub-ring relative to the main ring is improved as compared with the case where the main ring and the sub-ring are interlocked with a gear.

  According to the configuration of claim 2, since a predetermined tension is generated in the endless belt by energizing at least one of the plurality of sub-annular rings, the endless belt is prevented from loosening and the rotation angle of the main annular ring is set. The rotation angle of the secondary ring can be linked more accurately.

  According to the configuration of the third aspect, since the endless belt is configured by the cog belt that engages with the main ring and the sub ring, the main belt and the sub ring are prevented from slipping with respect to the main ring and the sub ring. The rotation angle of the sub-ring can be linked more accurately to the rotation angle of the ring.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 3 show an embodiment of the present invention. FIG. 1 is an overall plan view of a rotation angle detection device for detecting the rotation angle of a steering shaft. FIG. 2 is a sectional view taken along line 2-2 of FIG. 3 is a cross-sectional view taken along line 3-3 of FIG.

  A rotation angle detection device 11 for detecting the rotation angle of a steering wheel of an automobile is provided on a substrate 12 fixed to the vehicle body. An annular main pulley 14 is rotatably supported on the substrate 12 via a needle bearing 13. The outer periphery of the cylindrical steering shaft 15 is spline fitted 16 to the inner periphery of the main pulley 14. A first rotation shaft 19 protrudes downward from a first rotation angle sensor 18 fixed to the upper surface of a bracket 17 fixed to the substrate 12, and a first sub pulley 20 is supported on the first rotation shaft 19.

  An intermediate portion of the bell crank 22 is supported in a swingable manner on a support shaft 21 implanted in the substrate 12, and a second rotation shaft 24 projects downward from a second rotation angle sensor 23 fixed to the upper surface of one end portion thereof. The second sub pulley 25 is supported on the second rotating shaft 24. The bell crank 22 is urged counterclockwise in FIG. 1 by a coil spring 27 stretched between the other end of the bell crank 22 and a spring receiver 26 fixed to the substrate 12.

  A cog belt 28 is wound around the main pulley 14, the first sub pulley 20 and the second sub pulley 25. The main pulley 14, the first sub pulley 20, and the second sub pulley 25 are provided with frustoconical protrusions 14a, 20a, 25a, etc. on the outer periphery, and these protrusions 14a, 20a, 25a,. Are engaged with the holes 28a.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When the driver operates the steering handle to rotate the steering shaft 15, the main pulley 14 that is spline fitted 16 to the steering shaft 15 rotates, and the rotation of the main pulley 14 is caused by the first sub pulley 20 and the second pulley via the cog belt 28. It is transmitted to the sub pulley 25. Since the first and second auxiliary pulleys 20 and 25 have different diameters, the rotation angle of the first auxiliary pulley 20 detected by the first rotation angle sensor 18 and the second auxiliary pulley 25 detected by the second rotation angle sensor 23. The rotation angle of the main pulley 14, that is, the steering shaft 15, is detected from the combination of these two rotation angles.

  When the main pulley 14 and the first and second auxiliary pulleys 20 and 25 are interlocked with a gear instead of the cog belt 28, the first auxiliary pulley 20 is rotated when the main pulley 14 rotates clockwise and counterclockwise due to the influence of gear backlash. And the rotation angle of the 2nd sub pulley 25 changes, and there exists a problem that the detection accuracy of the rotation angle detection apparatus 11 falls. However, in this embodiment, the main pulley 14 and the first and second auxiliary pulleys 20 and 25 are interlocked by the cog belt 28, so that the influence of gear backlash is eliminated and the detection accuracy of the rotation angle detection device 11 is improved. Generation of noise can be suppressed.

  Further, in the interlocking with the gear, the degree of freedom of the arrangement of the first and second auxiliary pulleys 20 and 25 with respect to the main pulley 14 is limited, but by using the cog belt 28, the first and second auxiliary pulleys 20 and 25 are arranged. The degree of freedom of arrangement is improved. In addition, since the main pulley 14 and the first and second sub pulleys 20 and 25 and the cog belt 28 are engaged with each other, the cog belt 28 is prevented from slipping and the detection accuracy of the rotation angle detecting device 11 can be further improved. . Furthermore, since the second sub pulley 25 is urged by the elastic force of the coil spring 27 to apply tension to the cog belt 28, it is possible to prevent the detection accuracy of the rotation angle detecting device 11 from being lowered due to loosening of the cog belt 28.

  Although the embodiments of the present invention have been described above, various design changes can be made without departing from the scope of the present invention.

  For example, the rotation angle detection device 11 of the present invention can be applied to detection of the rotation angle of any shaft other than the steering shaft 15.

  Further, the rotation angle detection device 11 of the embodiment includes the two auxiliary pulleys 20 and 25, but the number of auxiliary pulleys may be three or more.

Overall plan view of a rotation angle detection device for detecting the rotation angle of the steering shaft 2-2 sectional view of FIG. 3-3 sectional view of FIG.

Explanation of symbols

14 Main pulley (Main ring)
15 Steering shaft (shaft)
18 First rotation angle sensor (rotation angle sensor)
20 1st sub pulley (sub ring)
23 Second rotation angle sensor (rotation angle sensor)
25 Second secondary pulley (secondary ring)
28 Cogbelt

Claims (3)

A main ring (14) provided on the outer periphery of the rotating shaft (15);
A plurality of sub-rings (20, 25) that rotate in conjunction with the rotation of the main ring (14);
A plurality of rotation angle sensors (18, 23) for respectively detecting rotation angles of the plurality of sub-annular rings (20, 25);
A rotation angle detecting device for detecting a rotation angle of the shaft (15) based on outputs of the plurality of rotation angle sensors (18, 23),
An endless belt (28) is wound around the main ring (14) and the plurality of sub rings (20, 25), and the plurality of sub rings (20, 25) are interlocked with the rotation of the main ring (14). 25) rotating angle detecting device characterized by rotating.   2. The rotation angle detecting device according to claim 1, wherein at least one of the plurality of sub-annular rings (20, 25) is biased to generate a predetermined tension on the endless belt (28). . The rotation angle according to claim 1 or 2, characterized in that the endless belt (28) is a cog belt which engages with the main ring (14) and the sub ring (20, 25) in an uneven manner. Detection device.

Images