JP2009229446A - Resolver device - Google Patents

Abstract

A resolver device suitable for preventing a decrease in accuracy due to a temperature change is provided.
A monopolar resolver 30a includes a resolver rotor 18a made of an annular stratified iron core and a resolver stator 20a made of an annular stratified iron core (silicon steel plate). The resolver rotors 18a and 18i are arranged to face the stator poles 20ap and 20ip at a predetermined interval, and are attached to the outer peripheral surface of the inner wall body 12a of the rotor 12 by bolts 18b. The inner wall member 12a is resolver rotor 18a, so that the thermal expansion coefficient close to 18i, the range of the linear expansion coefficient of ^{10.0 × 10 -6 [/℃]~17.5×10 -6 [} / ℃] Is set to
[Selection] Figure 1

Description

  The present invention relates to an apparatus including a resolver, and more particularly, to a resolver apparatus suitable for preventing a decrease in accuracy due to a temperature change.

Conventionally, as a technique using a resolver, for example, a rotary drive device described in Patent Document 1 is known.
FIG. 7 is a cross-sectional view in the axial direction of a conventional rotary drive device 400.
As shown in FIG. 7, the rotary drive device 400 is interposed between the housing inner 420 that is a stator, the rotor 12 that is a rotor, and the rotor 12 and the housing inner 420, and rotatably supports the rotor 12. And a cross roller bearing 14.

  The cross roller bearing 14 has an inner ring 14a and an outer ring 14b. The inner ring 14 a is fitted to the outer peripheral surface of the housing inner 420 and is fixed to the housing inner 420 while being pressed in the axial direction by the inner ring presser 26. The outer ring 14 b is fitted to the inner peripheral surface of the rotor 12 and is fixed to the rotor 12 while being pressed in the axial direction by the outer ring presser 28.

The rotor 12, the housing inner 420, the inner ring presser 26 and the outer ring presser 28 are made of aluminum in order to reduce the weight.
Between the rotor 12 and the housing inner 420, a motor unit 16 that applies rotational torque to the rotor 12 and a resolver 30 that detects a rotational angle position of the rotor 12 are provided.
The resolver 30 includes a resolver rotor 18 made of an annular stratified iron core and a resolver stator 20 made of an annular stratified iron core (silicon steel plate). The resolver stator 20 includes a stator core 20c having a plurality of stator poles 20p formed at equal intervals on the outer periphery of an annular member formed by laminating silicon steel plates, and a stator winding 20l wound around each stator pole 20p. The resolver rotor 18 has an inner circumference that is decentered with respect to the axis of the cross roller bearing 14, and is disposed to face the stator pole 20p with a predetermined interval. The resolver rotor 18 is integrally attached to the inner peripheral surface of the outer ring retainer 28, and the resolver stator 20 is integrally attached to the outer peripheral surface of the inner ring retainer 26.
JP 2006-21806 A

  However, in the conventional rotary drive device 400, the resolver rotor 18 is made of a silicon steel plate, whereas the outer ring presser 28 for fixing the resolver rotor 18 is made of aluminum. Due to the temperature change around the bearing, the outer ring presser 28 having a higher thermal expansion coefficient than the resolver rotor 18 expands, and the outer ring presser 28 presses the resolver rotor 18 radially inward.

Similarly, while the stator core 20c is made of a silicon steel plate, the inner ring presser 26 for fixing the stator core 20c is made of aluminum, so that the temperature change around the bearing during motor driving causes more heat than the stator core 20c. The inner ring presser 26 having a higher expansion rate expands, and the inner ring presser 26 presses the stator core 20c radially outward.
As a result, there is a problem that a gap change occurs between the resolver rotor 18 and the resolver stator 20 and the accuracy of the resolver 30 is lowered.

FIG. 8 is a graph showing the position detection error of the resolver 30.
When the resolver 30 has three phases, the most accurate resolver signal is expressed by the following equation (1).

A = (Adc + Aac · sinθ) · Esinωt
B = (Bdc + Bac · sin (θ + 120 °)) · Esinωt
C = (Cdc + Cac · sin (θ + 240 °)) · Esinωt (1)

In the above equation (1), Adc, Bdc, and Cdc are DC components of each phase, Aac, Bac, and Cac are maximum amplitudes of AC components of each phase, and Esinωt is an excitation signal component.

At normal temperature, the gap of the resolver 30 is adjusted appropriately, so that the error is small as shown in FIG. On the other hand, when the resolver rotor 18 is pressed and the gap changes at the time of temperature rise, the AC components Aac, Bac, Cac at normal temperature and the AC components Aac, Bac, Cac at temperature rise do not match.
In the system that corrects the error based on the correction data, the correction accuracy is affected by the amplitude value of the two-phase resolver signal (sin signal, cos signal) converted from the three-phase resolver signal. Since changes in Aac, Bac, and Cac are calculated as correction errors, the errors increase as shown in FIG.

  On the other hand, when the stator core 20c is pressed and the gap changes when the temperature rises, the stator pole 20p is also deformed, and the resolver signals A to C are unbalanced. That is, since DC component Adc ≠ Bdc ≠ Cdc, the error increases as shown in FIG.

  Further, in the system that corrects the error based on the correction data, the correction accuracy is affected by the ratio of the DC components Adc, Bdc, and Cdc. Therefore, variations in the DC components Adc, Bdc, and Cdc become correction errors. It is calculated.

  Accordingly, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and an object thereof is to provide a resolver device suitable for preventing a decrease in accuracy due to a temperature change. It is said.

  [Invention 1] In order to achieve the above object, a resolver device of Invention 1 comprises a stator core having a plurality of poles formed on the inner periphery or outer periphery of an annular member, and a stator winding wound around the poles of the stator core. A resolver having a resolver stator and a resolver rotor disposed to face the pole of the stator core, and a resolver in which a reluctance between the resolver rotor and the resolver stator changes according to a position of the resolver rotor, and the resolver rotor is fixed The resolver device includes a fixed member to be fixed, and the fixed member is made of a material having a thermal expansion coefficient that is the same as or close to that of the resolver rotor.

With such a configuration, when the temperature around the bearing rises, the resolver rotor and the fixed member expand, but the thermal expansion coefficient of the resolver rotor and the fixed member are the same or similar. The degree to which the resolver rotor is pressed by the fixed member is small. Therefore, the change in the resolver gap is reduced.
Here, the thermal expansion coefficient that is the same as or close to that of the resolver rotor includes, for example, that the ratio of the thermal expansion coefficient of the fixed member to the thermal expansion coefficient of the resolver rotor is 77 [%] to 135 [%]. It is.

[Invention 2] Further, the resolver device of Invention 2 is the resolver device of Invention 1, wherein the resolver rotor is made of silicon steel, and the fixed member is made of iron or stainless steel.
With such a configuration, since the thermal expansion coefficient of the resolver rotor and the thermal expansion coefficient of the fixed member are approximately the same, even if the temperature around the bearing rises, the resolver rotor is pressed by the fixed member. The degree is small.

[Invention 3] Further, the resolver apparatus of Invention 3 is the resolver apparatus of Invention 1, wherein the resolver rotor is made of silicon steel, and the linear expansion coefficient of the fixed member is 10.0 × 10 ⁻⁶ [/ ° C. ] To 17.5 × 10 ⁻⁶ [/ ° C.].
With such a configuration, since the thermal expansion coefficient of the resolver rotor and the thermal expansion coefficient of the fixed member are the same or similar, even if the temperature around the bearing rises, the resolver rotor is pressed by the fixed member. The degree of being done is small.

[Invention 4] The resolver device according to Invention 4 is the resolver device according to any one of Inventions 1 to 3, further comprising a second fixed member to which the stator core is fixed, and the second fixed member is It is made of a material having a coefficient of thermal expansion that is the same as or close to that of the stator core.
With such a configuration, when the temperature around the bearing rises, the stator core and the second fixed member expand, but the coefficient of thermal expansion of the stator core and the coefficient of thermal expansion of the second fixed member are the same or similar. Therefore, even if the temperature around the bearing rises, the degree to which the stator core is pressed by the second fixed member is small. Therefore, the change in the resolver gap is further reduced.
Here, as the thermal expansion coefficient that is the same as or close to that of the stator core, for example, the ratio of the thermal expansion coefficient of the second fixed member to the thermal expansion coefficient of the resolver rotor is 77 [%] to 135 [%]. included.

[Invention 5] The resolver device according to Invention 5 is the resolver device according to Invention 4, wherein the stator core is made of silicon steel, and the second fixed member is made of iron or stainless steel.
With such a configuration, since the thermal expansion coefficient of the stator core and the thermal expansion coefficient of the second fixed member are approximately the same, even if the temperature around the bearing rises, the stator core is pressed by the second fixed member. The degree of being done is small.

[Invention 6] Further, the resolver device of Invention 6 is the resolver device of Invention 4, wherein the stator core is made of silicon steel, and the linear expansion coefficient of the second fixed member is 10.0 × 10 ⁻⁶ [/ ° C.] to 17.5 × 10 ⁻⁶ [/ ° C.].

  With such a configuration, since the coefficient of thermal expansion of the stator core and the coefficient of thermal expansion of the second fixed member are the same or similar, even if the temperature around the bearing rises, the stator core is driven by the second fixed member. The degree to which is pressed is small.

[Invention 7] The resolver device of Invention 7 further includes a stator core having a plurality of poles formed on the inner periphery or outer periphery of an annular member, a resolver stator including a stator winding wound around the poles of the stator core, and the stator core A resolver having a resolver rotor disposed so as to be opposed to the pole, a resolver in which a reluctance between the resolver rotor and the resolver stator varies depending on a position of the resolver rotor, and a fixed member to which the stator core is fixed. It is a resolver apparatus provided, Comprising: The said to-be-fixed member is comprised with the material of the thermal expansion coefficient which is the same as that of the said stator core, or near this.
With such a configuration, when the temperature around the bearing rises, the stator core and the fixed member expand, but the coefficient of thermal expansion of the stator core and the coefficient of thermal expansion of the fixed member are the same or similar. Even if the surrounding temperature rises, the degree to which the stator core is pressed by the fixed member is small. Therefore, the change in the resolver gap is reduced.
Here, the thermal expansion coefficient that is the same as or close to that of the stator core includes, for example, that the ratio of the thermal expansion coefficient of the fixed member to the thermal expansion coefficient of the resolver rotor is 77 [%] to 135 [%]. .

[Invention 8] The resolver device according to Invention 8 is the resolver device according to Invention 7, wherein the stator core is made of silicon steel, and the fixed member is made of iron or stainless steel.
With such a configuration, since the coefficient of thermal expansion of the stator core and the coefficient of thermal expansion of the fixed member are approximately the same, the degree to which the stator core is pressed by the fixed member even when the temperature around the bearing rises. small.

[Invention 9] Further, the resolver device of Invention 9 is the resolver device of Invention 7, wherein the stator core is made of silicon steel, and the linear expansion coefficient of the fixed member is 10.0 × 10 ⁻⁶ [/ ° C.]. ˜17.5 × 10 ⁻⁶ [/ ° C.].
With such a configuration, since the coefficient of thermal expansion of the stator core and the coefficient of thermal expansion of the fixed member are the same or similar, the stator core is pressed by the fixed member even when the temperature around the bearing rises. The degree is small.

As described above, according to the resolver device of the first aspect, even if the temperature around the bearing rises, the degree to which the resolver rotor is pressed by the fixed member is small. The effect that the fall of the precision by a temperature change can be suppressed can be acquired.
Furthermore, according to the resolver device of the invention 4, even if the temperature around the bearing rises, the degree to which the resolver rotor is pressed by the fixed member is small, and the degree to which the stator core is pressed by the second fixed member is also small. Thus, it is possible to further reduce the gap change of the resolver, and to obtain an effect of further suppressing the decrease in accuracy due to the temperature change.

  Furthermore, according to the resolver device of the invention 7, even if the temperature around the bearing rises, the degree to which the stator core is pressed by the member to be fixed is small, so that the change in the resolver gap can be reduced compared to the conventional case. This is advantageous in that a decrease in accuracy due to a temperature change can be suppressed.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 are views showing a first embodiment of a resolver device according to the present invention.
First, the configuration of the resolver device 100 according to the present embodiment will be described.
FIG. 1 is a cross-sectional view of the resolver device 100 in the axial direction.

  As shown in FIG. 1, the resolver device 100 includes a stator 22 that is a stator, a rotor 12 that is a rotor, and a cross roller bearing that is interposed between the rotor 12 and the stator 22 and rotatably supports the rotor 12. 14 and a monopolar resolver 30a and a multipolar resolver 30i for detecting the rotational angle position of the rotor 12. Here, the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same plane in the radial direction in that order from the radial inner side.

  The stator 22 is formed with an annular inner wall body 22a protruding upward in the axial direction (upward in FIG. 1), and an annular outer wall body protruding upward in the axial direction on the outer side in the radial direction than the inner wall body 22a. 22b is formed. On the other hand, the rotor 12 is formed with an annular inner wall body 12a protruding downward in the axial direction (downward in FIG. 1), and the annular wall protruding downward in the axial direction is formed radially outward from the inner wall body 12a. An outer wall body 12b is formed. The stator 22 and the rotor 12 include an inner wall 22a of the stator 22 between the inner wall 12a and the outer wall 12b of the rotor 12, and an outer wall 12b of the rotor 12 between the inner wall 22a and the outer wall 22b of the stator 22. They are arranged so as to be positioned.

The cross roller bearing 14 includes an inner ring 14a, an outer ring 14b, and a plurality of cross rollers (rollers) 14c provided so as to be able to roll between the inner ring 14a and the outer ring 14b. The cross roller 14c has a substantially cylindrical shape whose diameter is slightly larger than the length, and the even-numbered rotation shaft on the track and the odd-numbered rotation shaft on the track are inclined by 90 °.
The inner ring 14 a is fixed to the inner wall body 22 a of the stator 22 while being pressed in the axial direction. Specifically, the upper end of the inner wall body 22a of the stator 22 is brought into contact with the lower surface of the inner ring 14a, the pressing portion 26b of the inner ring presser 26 is brought into contact with the upper surface of the inner ring 14a, and the inner ring presser 26 is connected to the inner wall of the stator 22 with a bolt 26a. It is fixed by fastening to the body 22a.

The outer ring 14b is fixed to the outer wall body 12b of the rotor 12 while being pressed in the axial direction. Specifically, the lower end of the outer wall body 12b of the rotor 12 is brought into contact with the upper surface of the outer ring 14b, the pressing portion 28b of the outer ring presser 28 is brought into contact with the lower surface of the outer ring 14b, and the outer ring presser 28 is connected to the outer wall of the rotor 12 with bolts 28a. It is fixed by fastening to the body 12b.
Note that a fixing plate 24 is fixed to the stator 22 by bolts 24a, and the rotor 12 is fitted to a rotating shaft of a motor (described later).

  The monopolar resolver 30a is an ABS (Absolute) type inner rotor resolver, and includes a resolver rotor 18a made of an annular stratified iron core and a resolver stator 20a made of an annular stratified iron core (silicon steel plate). Has been. Resolver stator 20a has a stator core 20ac in which a plurality of stator poles 20ap are formed at equal intervals on the inner periphery of an annular member formed by laminating silicon steel plates, and stator windings 20al wound around each stator pole 20ap. The resolver rotor 18a has an outer periphery that is eccentric with respect to the axis of the cross roller bearing 14, and is disposed to face the stator pole 20ap at a predetermined interval. Therefore, a unipolar resolver signal is output in which the fundamental wave component of the reluctance change is one cycle per revolution of the resolver rotor 18a.

  The multipolar resolver 30i is an INC (Increment) type inner rotor resolver, and includes a resolver rotor 18i made of an annular stratified iron core and a resolver stator 20i made of an annular stratified iron core (silicon steel plate). Has been. Resolver stator 20i has a stator core 20ic in which a plurality of stator poles 20ip are formed at equal intervals on the inner periphery of an annular member formed by laminating silicon steel plates, and a stator winding 20il wound around each stator pole 20ip. The resolver rotor 18i has a plurality of salient pole-like teeth formed at equal intervals in the circumferential direction, and is disposed to face the stator pole 20ip with a predetermined interval. For this reason, a multipolar resolver signal in which the fundamental wave component of the reluctance change is multi-period per rotation of the resolver rotor 18i is output.

  The resolver rotors 18a and 18i are arranged at a minute interval via a rotor spacer 42, and are attached to the outer peripheral surface of the inner wall body 12a of the rotor 12 by bolts 18b. On the other hand, the stator cores 20ac and 20ic are arranged at a minute interval via a stator spacer 44, attached to the inner peripheral surface of the inner ring retainer 26 by bolts 20b, and integrated with the inner ring retainer 26 in the inner wall 22a of the stator 22. It is fixed on the peripheral surface side.

The rotor 12 (including the inner wall body 12a) has a linear expansion coefficient of 10.0 × 10 ⁻⁶ [/ ° C.] to 17.5 × 10 ⁻ so that the thermal expansion coefficient is close to that of the resolver rotors 18a and 18i. ⁶ The range is set to [/ ° C]. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.

Next, the configuration of the control system according to the present embodiment will be described.
FIG. 2 is a block diagram showing the configuration of the control system.
As shown in FIG. 2, the control system includes a motor 310, a resolver device 100 fitted to the outer peripheral surface of the rotation shaft of the motor 310, and a relay device that detects a rotational angle position based on a resolver signal from the resolver device 100. 200 and a motor control device 300 that controls the motor 310 based on the rotation angle position detected by the relay device 200.

The relay device 200 includes an oscillator 50, an amplifier 52 that amplifies the excitation signal output from the oscillator 50 to an appropriate signal level, and a changeover switch 54 that supplies the excitation signal from the amplifier 52 to one of the resolvers 30a and 30i. It is comprised.
The changeover switch 54 is connected to connect the amplifier 52 and the common terminal COM1 of the unipolar resolver 30a based on the given switch changeover signal, and to connect the amplifier 52 and the common terminal COM2 of the multipolar resolver 30i. Switch to one of the states.

The relay apparatus 200 further includes current / voltage converters 56a and 56b, 3/2 phase converters 58a and 58b, an analog switch 60, a phase shifter 62, and an RDC (Resolver Digital Converter) 64. .
From the monopolar resolver 30a, three-phase monopolar resolver signals whose phases are different from each other by 120 ° are output. The three-phase unipolar resolver signal is converted into a current / voltage by the current / voltage converter 56a, and converted into a two-phase unipolar resolver signal (sin signal, cos signal) by the 3/2 phase converter 58a. The two-phase unipolar resolver signal is output to the analog switch 60.

On the other hand, the multipolar resolver 30i outputs three-phase multipolar resolver signals whose phases are different from each other by 120 °. The three-phase multipolar resolver signal is current / voltage converted by the current / voltage converter 56b, and converted to a two-phase multipolar resolver signal (sin signal, cos signal) by the 3/2 phase converter 58b. The two-phase multipolar resolver signal is output to the analog switch 60.
Based on the given ABS / INC switching signal, the analog switch 60 passes either the unipolar resolver signal or the multipolar resolver signal and supplies it to the RDC 64.

The phase shifter 62 delays the phase of the excitation signal output from the oscillator 50 and supplies the RDC 64 with a Ref signal synchronized with the phase of the carrier signal of the two-phase unipolar resolver signal or multipolar resolver signal.
The RDC 64 samples the unipolar resolver signal or the multipolar resolver signal from the analog switch 60 based on the Ref signal from the phase shifter 62 at a predetermined cycle, and the signal value obtained by sampling is sampled as a digital angle signal φ. Output.

The relay device 200 further includes a memory 66 that stores correction data, a CPU 68 that detects a rotational angle position based on the digital angle signal φ from the RDC 64, and a control signal input / output that communicates with the motor control device 300. Unit 70, position detection signal output unit 72, and abnormality detection signal output unit 74.
After the power is turned on, the CPU 68 supplies the excitation signal to the monopolar resolver 30a by outputting a switch change signal to the changeover switch 54, and inputs the digital angle signal φ of the monopolar resolver signal from the RDC 64. At this time, an ABS / INC switching signal is output to the analog switch 60 so that the switching timings of the analog switch 60 and the changeover switch 54 are synchronized. Next, an excitation signal is supplied to the multipolar resolver 30 i by outputting a switch switching signal to the changeover switch 54, and a digital angle signal φ of the multipolar resolver signal is input from the RDC 64. Then, this operation is repeated at a predetermined cycle.

The correction data for the unipolar resolver signal is obtained by sampling the unipolar resolver signal output from the unipolar resolver 30a over the entire mechanical angle of the unipolar resolver 30a at the sampling period of the RDC 64, and the signal value obtained by sampling. Created as a difference (error) from the ideal value.
The correction data for the multipolar resolver signal is obtained by sampling the multipolar resolver signal output from the multipolar resolver 30i over the entire mechanical angle of the multipolar resolver 30i at the sampling period of the RDC 64, and the signal value obtained by sampling. Created as a difference from the ideal value.

  The CPU 68 subtracts the correction data for the unipolar resolver signal in the memory 66 from the digital angle signal value of the unipolar resolver signal, and the correction data for the multipolar resolver signal in the memory 66 is subtracted from the digital angle signal value of the multipolar resolver signal. The rotation angle position is calculated by subtraction, and rotation angle position detection data indicating the rotation angle position with high accuracy using the calculated rotation angle position as a component is generated.

  The CPU 68 outputs a rotation angle position detection signal indicating rotation angle position detection data to the motor control device 300 via the position detection signal output unit 72. A control signal is input / output to / from the motor control device 300 via the control signal input / output unit 70, and an abnormality detection signal is output to the motor control device 300 via the abnormality detection signal output unit 74.

Next, the operation of the present embodiment will be described.
When the motor 310 rotates, rotational torque is applied to the rotor 12 and the rotor 12 rotates. Then, the resolver 30a, 30i detects a change in reluctance between the resolver rotors 18a, 18i rotating integrally with the rotor 12, and outputs a resolver signal.
In the relay apparatus 200, the resolver signal is input to the RDC 64 via the current / voltage converters 56a and 56b, the 3/2 phase converters 58a and 58b, and the analog switch 60. The resolver signal is sampled at a predetermined period by the RDC 64, and the signal value obtained by sampling is output as a digital angle signal.

  In the relay device 200, when the sampling timing is reached, the CPU 68 acquires the digital angle signal values of the monopolar resolver signal and the multipolar resolver signal, and the rotation angle position based on the acquired digital angle signal value and the correction data of the memory 66. Are calculated respectively. Then, rotation angle position detection data indicating a highly accurate rotation angle position having these rotation angle positions as components is output.

In the motor control device 300, the motor 310 is controlled based on the rotation angle position detection data.
On the other hand, when the temperature around the bearing rises during driving, the resolver rotors 18a and 18i and the inner wall body 12a adjacent thereto expand, but the thermal expansion coefficient of the resolver rotors 18a and 18i and the thermal expansion coefficient of the inner wall body 12a are increased. Since the degree is the same, the degree to which the resolver rotors 18a and 18i are pressed by the inner wall body 12a is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the change in the AC components Aac, Bac, and Cac in the above equation (1) is reduced.

Further, when a moment load is applied to the resolver device 100, the resolver device 100 tilts around the cross roller bearing 14, but the resolvers 30a and 30i are disposed on the same plane in the radial direction as the cross roller bearing 14, and therefore the resolver 30a. 30i can be reduced.
In addition, since the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same plane in the radial direction, the height (the length in the axial direction) of the resolver device 100 can be reduced.

  Furthermore, when a method such as increasing the preload of the cross roller bearing 14 is adopted, the gap change can be suppressed, but on the other hand, there is a problem that the life of the cross roller bearing 14 is shortened. Since the change in the gap is reduced by arranging the resolvers 30a and 30i at a position where the cross roller bearing is small, the life of the cross roller bearing 14 can be extended.

Thus, in the present embodiment, resolver device 100 includes resolvers 30a and 30i and inner wall body 12a to which resolver rotors 18a and 18i are fixed, and inner wall body 12a is made of an iron material such as S45C or stainless steel. Configured.
As a result, even if the temperature around the bearing rises, the degree to which the resolver rotors 18a and 18i are pressed by the inner wall body 12a is small, so that the change in the gaps of the resolvers 30a and 30i can be reduced compared to the conventional case. Further, it is possible to suppress a decrease in accuracy due to a temperature change.

  Further, in the present embodiment, resolver device 100 includes cross roller bearing 14 having inner ring 14a and outer ring 14b, stator 22 supported by inner ring 14a, rotor 12 supported by outer ring 14b, and rotation of rotor 12. Resolvers 30a and 30i that detect angular positions are provided, and the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same radial plane.

  Thus, even when a moment load is applied to the resolver device 100, the resolver 30a, 30i is disposed at a position where the gap change is small. Therefore, the gap change of the resolver 30a, 30i can be reduced, and the accuracy due to the moment load can be reduced. The decrease can be suppressed. Moreover, since the resolvers 30a and 30i and the cross roller bearing 14 are arrange | positioned on the radial direction same plane, the height of the resolver apparatus 100 can be made small. Furthermore, the life of the cross roller bearing 14 can be extended as compared with a method of increasing the preload of the cross roller bearing 14.

Further, in the present embodiment, the cross roller bearing 14 is employed.
Thereby, since moment load, axial load, and radial load can be received simultaneously, gap change due to moment load can be reduced while maintaining rigidity against axial load and radial load.
In the said 1st Embodiment, the inner wall body 12a respond | corresponds to the to-be-fixed member of the invention 1 thru | or 3.

[Modification of First Embodiment]
In the first embodiment, the cross roller bearing 14 is applied. However, the present invention is not limited to this. A four-point contact ball bearing, an angular ball bearing, a deep groove ball bearing, a cylindrical roller bearing, and a tapered roller bearing. Etc. may be applied. In this case, it is preferable to employ a rolling bearing that can simultaneously receive a moment load, an axial load, and a radial load. An example of such a rolling bearing is a four-point contact ball bearing.

  FIG. 3 is a sectional view in the axial direction of a resolver device 100 in which the cross roller bearing 14 is changed to a four-point contact ball bearing 15 as a modified example of the first embodiment. In the modification of the first embodiment shown in FIG. 3, the first point shown in FIG. 1 and FIG. 2 is used except that a four-point contact ball bearing 15 is adopted as a bearing that rotatably supports the rotor 12. Since it is the same as that of embodiment, description is abbreviate | omitted about the same structure which attached | subjected the same code | symbol as 1st Embodiment.

As shown in FIG. 3, the four-point contact ball bearing 15 includes an inner ring 15a, an outer ring 15b, and a plurality of balls 15c provided so as to be able to roll between the inner ring 15a and the outer ring 15b. Yes.
The inner ring 15 a is fixed to the inner wall body 22 a of the stator 22 while being pressed in the axial direction. Specifically, the upper end of the inner wall body 22a of the stator 22 is brought into contact with the lower surface of the inner ring 15a, the pressing portion 26b of the inner ring presser 26 is brought into contact with the upper surface of the inner ring 15a, and the inner ring presser 26 is connected to the inner wall of the stator 22 with a bolt 26a. It is fixed by fastening to the body 22a.

The outer ring 15b is fixed to the outer wall body 12b of the rotor 12 while being pressed in the axial direction. Specifically, the lower end of the outer wall body 12b of the rotor 12 is brought into contact with the upper surface of the outer ring 15b, the pressing portion 28b of the outer ring presser 28 is brought into contact with the lower surface of the outer ring 15b, and the outer ring presser 28 is connected to the outer wall of the rotor 12 with bolts 28a. It is fixed by fastening to the body 12b.
As described above, by adopting the four-point contact ball bearing 15 as a bearing that rotatably supports the rotor 12, it is possible to keep friction load low while maintaining load resistance, and to keep loss during rotation low. Can do. In addition, since the rolling elements (balls) used for ball bearings have less contact than the rolling elements (rollers) used for cross roller bearings, heat generation during rotation of the bearings can be suppressed and higher speed rotation is possible. A position detector can be realized.

[Modification of First Embodiment]
Moreover, in the said 1st Embodiment, although comprised with the inner rotor type | mold which the inner side of the resolver apparatus 100 rotates, it can comprise not only this but the outer rotor type | mold which the outer side of the resolver apparatus 100 rotates. .

FIG. 4 is an axial sectional view of the outer rotor type resolver device 100.
As shown in FIG. 4, the resolver device 100 rotatably supports the rotor 12 by being interposed between a housing inner 110 that is a stator, a rotor 12 that is a rotor, and the rotor 12 and the housing inner 110. And a point contact ball bearing 15.
The four-point contact ball bearing 15 includes an inner ring 15a, an outer ring 15b, and a plurality of balls 15c provided so as to be able to roll between the inner ring 15a and the outer ring 15b. The inner ring 15 a is fitted to the outer peripheral surface of the housing inner 110, and is fixed to the housing inner 110 while being pressed in the axial direction by the inner ring presser 26. The outer ring 15 b is fitted to the inner peripheral surface of the rotor 12 and is fixed to the rotor 12 while being pressed in the axial direction by the outer ring presser 28.

A resolver 30 that detects the rotational angle position of the rotor 12 is provided between the rotor 12 and the housing inner 110.
The resolver 30 includes a resolver rotor 18 made of an annular stratified iron core and a resolver stator 20 made of an annular stratified iron core (silicon steel plate). The resolver rotor 18 has an inner circumference that is eccentric with respect to the axis of the four-point contact ball bearing 15, and is disposed to face the resolver stator 20 with a predetermined interval. The resolver rotor 18 is integrally attached to the inner peripheral surface of the outer ring retainer 28, and the resolver stator 20 is integrally attached to the outer peripheral surface of the inner ring retainer 26.

Thus, by adopting an outer rotor type as an aspect of the resolver device 100, the hollow hole formed by the inner peripheral surface of the housing inner 110 is fixed, and the resolver device 100 is incorporated in a mechanism in which the rotor 12 rotates. In some cases, the design can be facilitated.
In addition, the kind of bearing which supports the rotor 12 rotatably is not restrict | limited to the 4-point contact ball bearing 15, and is suitably selected according to the objective. Examples of other types of four-point contact ball bearings include cross roller bearings, angular ball bearings, deep groove ball bearings, cylindrical roller bearings, and tapered roller bearings. Among these, a four-point contact ball bearing that can simultaneously receive a moment load, an axial load, and a radial load is particularly preferable.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a diagram showing a resolver device according to a second embodiment of the present invention.
The structure of the resolver apparatus 100 which concerns on this Embodiment is demonstrated.

FIG. 5 is a sectional view of the resolver device 100 in the axial direction.
As shown in FIG. 5, the resolver device 100 includes a stator 22 that is a stator, a rotor 12 that is a rotor, and a cross roller bearing that is interposed between the rotor 12 and the stator 22 to rotatably support the rotor 12. 14 and a monopolar resolver 30a and a multipolar resolver 30i for detecting the rotational angle position of the rotor 12. Here, the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same plane in the radial direction in that order from the radial inner side.

  The stator 22 is formed with an annular inner wall body 22a protruding upward in the axial direction (upward in FIG. 5), and an annular outer wall body protruding upward in the axial direction on the radially outer side of the inner wall body 22a. 22b is formed. On the other hand, the rotor 12 is formed with an annular inner wall 12a protruding downward in the axial direction (downward in FIG. 5), and an annular inner wall 12a protruding downward in the axial direction is formed radially outward from the inner wall 12a. An outer wall body 12b is formed. The stator 22 and the rotor 12 include an inner wall body 12a of the rotor 12 between the inner wall body 22a and the outer wall body 22b of the stator 22, and an outer wall body 22b of the stator 22 between the inner wall body 12a and the outer wall body 12b of the rotor 12. They are arranged so as to be positioned.

The cross roller bearing 14 includes an inner ring 14a, an outer ring 14b, and a plurality of cross rollers (rollers) 14c provided so as to be able to roll between the inner ring 14a and the outer ring 14b. The cross roller 14c has a substantially cylindrical shape whose diameter is slightly larger than the length, and the even-numbered rotation shaft on the track and the odd-numbered rotation shaft on the track are inclined by 90 °.
The inner ring 14 a is fixed to the inner wall body 12 a of the rotor 12 while being pressed in the axial direction. Specifically, a step portion 12c formed on the outer peripheral surface of the inner wall body 12a of the rotor 12 is brought into contact with the upper surface of the inner ring 14a, the inner ring presser 26 is brought into contact with the lower surface of the inner ring 14a, and the inner ring presser 26 is secured with a bolt 26a. The rotor 12 is fixed by fastening to the inner wall body 12a.

The outer ring 14 b is fixed to the outer wall body 22 b of the stator 22 while being pressed in the axial direction. Specifically, a step portion 22c formed on the inner peripheral surface of the outer wall body 22b of the stator 22 is brought into contact with the lower surface of the outer ring 14b, the outer ring presser 28 is brought into contact with the upper surface of the outer ring 14b, and the outer ring presser 28 is connected to the bolt 28a. Then, it is fixed by fastening to the outer wall body 22b of the stator 22.
The stator 22 is fixed to the stator 22 by bolts 24 a, and the rotor 12 is fitted to the rotating shaft of the motor 310.

  The monopolar resolver 30a is an ABS type outer rotor type resolver, and includes a resolver rotor 18a made of an annular stratified iron core and a resolver stator 20a made of an annular stratified iron core (silicon steel plate). . Resolver stator 20a has a stator core 20ac in which a plurality of stator poles 20ap are formed at equal intervals on the outer periphery of an annular member formed by laminating silicon steel plates, and stator windings 20al wound around each stator pole 20ap. The resolver rotor 18a has an inner circumference that is eccentric with respect to the axis of the cross roller bearing 14, and is disposed to face the stator pole 20ap with a predetermined interval. Therefore, a unipolar resolver signal is output in which the fundamental wave component of the reluctance change is one cycle per revolution of the resolver rotor 18a.

  The multipolar resolver 30i is an INC-type outer rotor type resolver, and includes a resolver rotor 18i made of an annular stratified iron core and a resolver stator 20i made of an annular stratified iron core (silicon steel plate). . Resolver stator 20i has a stator core 20ic in which a plurality of stator poles 20ip are formed at equal intervals on the outer periphery of an annular member formed by laminating silicon steel plates, and a stator winding 20il wound around each stator pole 20ip. The resolver rotor 18i has a plurality of salient pole-like teeth formed at equal intervals in the circumferential direction, and is disposed to face the stator pole 20ip with a predetermined interval. For this reason, a multipolar resolver signal in which the fundamental wave component of the reluctance change is multi-period per rotation of the resolver rotor 18i is output.

  The resolver rotors 18a and 18i are arranged at a minute interval via the rotor spacer 42, and are attached to the inner peripheral surface of the inner wall body 12a of the rotor 12 by bolts 18b. On the other hand, the stator cores 20ac and 20ic are arranged with a small interval through a stator spacer 44, and are attached to the outer peripheral surface of the inner wall body 22a of the stator 22 by bolts 20b.

The rotor 12 (including the inner wall body 12a) has a linear expansion coefficient of 10.0 × 10 ⁻⁶ [/ ° C.] to 17.5 × 10 ⁻ so that the thermal expansion coefficient is close to that of the resolver rotors 18a and 18i. ⁶ The range is set to [/ ° C]. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.
The control system is the same as that in the first embodiment.

Next, the operation of the present embodiment will be described.
When the motor 310 rotates, rotational torque is applied to the rotor 12 and the rotor 12 rotates. Then, the resolver 30a, 30i detects a change in reluctance between the resolver rotors 18a, 18i rotating integrally with the rotor 12, and outputs a resolver signal.

In the relay apparatus 200, the resolver signal is input to the RDC 64 via the current / voltage converters 56a and 56b, the 3/2 phase converters 58a and 58b, and the analog switch 60. The resolver signal is sampled at a predetermined period by the RDC 64, and the signal value obtained by sampling is output as a digital angle signal.
In the relay device 200, when the sampling timing is reached, the CPU 68 acquires the digital angle signal values of the monopolar resolver signal and the multipolar resolver signal, and the rotation angle position based on the acquired digital angle signal value and the correction data of the memory 66. Are calculated respectively. Then, rotation angle position detection data indicating a highly accurate rotation angle position having these rotation angle positions as components is output.

In the motor control device 300, the motor 310 is controlled based on the rotation angle position detection data.
On the other hand, when the temperature around the bearing rises during driving, the resolver rotors 18a and 18i and the inner wall body 12a adjacent thereto expand, but the thermal expansion coefficient of the resolver rotors 18a and 18i and the thermal expansion coefficient of the inner wall body 12a are increased. Since the degree is the same, the degree to which the resolver rotors 18a and 18i are pressed by the inner wall body 12a is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the change in the AC components Aac, Bac, and Cac in the above equation (1) is reduced.

Further, when a moment load is applied to the resolver device 100, the resolver device 100 tilts around the cross roller bearing 14, but the resolvers 30a and 30i are disposed on the same plane in the radial direction as the cross roller bearing 14, and therefore the resolver 30a. 30i can be reduced.
In addition, since the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same plane in the radial direction, the height (the length in the axial direction) of the resolver device 100 can be reduced.

  Furthermore, when a method such as increasing the preload of the cross roller bearing 14 is adopted, the gap change can be suppressed, but on the other hand, there is a problem that the life of the cross roller bearing 14 is shortened. Since the change in the gap is reduced by arranging the resolvers 30a and 30i at a position where the cross roller bearing is small, the life of the cross roller bearing 14 can be extended.

Thus, in the present embodiment, resolver device 100 includes resolvers 30a and 30i and inner wall body 12a to which resolver rotors 18a and 18i are fixed, and inner wall body 12a is made of an iron material such as S45C or stainless steel. Configured.
As a result, even if the temperature around the bearing rises, the degree to which the resolver rotors 18a and 18i are pressed by the inner wall body 12a is small, so that the change in the gaps of the resolvers 30a and 30i can be reduced compared to the conventional case. Further, it is possible to suppress a decrease in accuracy due to a temperature change.

  Further, in the present embodiment, resolver device 100 includes cross roller bearing 14 having inner ring 14a and outer ring 14b, stator 22 supported by inner ring 14a, rotor 12 supported by outer ring 14b, and rotation of rotor 12. Resolvers 30a and 30i that detect angular positions are provided, and the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same radial plane.

  Thus, even when a moment load is applied to the resolver device 100, the resolver 30a, 30i is disposed at a position where the gap change is small. Therefore, the gap change of the resolver 30a, 30i can be reduced, and the accuracy due to the moment load can be reduced. The decrease can be suppressed. Moreover, since the resolvers 30a and 30i and the cross roller bearing 14 are arrange | positioned on the radial direction same plane, the height of the resolver apparatus 100 can be made small. Furthermore, the life of the cross roller bearing 14 can be extended as compared with a method of increasing the preload of the cross roller bearing 14.

Further, in the present embodiment, the cross roller bearing 14 is employed.
Thereby, since moment load, axial load, and radial load can be received simultaneously, gap change due to moment load can be reduced while maintaining rigidity against axial load and radial load.
In the second embodiment, the inner wall body 12a corresponds to the fixed member of the first to third aspects.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a diagram showing a third embodiment of a resolver device according to the present invention.
The structure of the resolver apparatus 100 which concerns on this Embodiment is demonstrated.

FIG. 6 is a sectional view of the resolver device 100 in the axial direction.
As shown in FIG. 6, the resolver device 100 includes an outer 420 a and 420 b that are stators, a rotor 12 that is a rotor, and an angular member that is interposed between the rotor 12 and the outer 420 a and rotatably supports the rotor 12. The ball bearings 84 and 85, and a single pole resolver 30 a and a multipolar resolver 30 i that detect the rotational angle position of the rotor 12 are configured. Here, the resolvers 30a and 30i and the angular ball bearings 84 and 85 are arranged on the same radial plane in that order from the radial inner side.

  The outer 420b has a housing 420bb that penetrates the shaft accommodating portion 12d into the shaft center with a gap, and an inner wall body 420bw that rises upward in the axial direction (upward in FIG. 6) along the inner peripheral surface of the housing 420bb. Configured. The outer 420a is formed of a cylindrical body and is placed on the housing 420bb. In addition, a concave portion recessed radially inward is formed at the lower outer peripheral surface of the outer 420a, and a convex portion is formed at the upper outer peripheral surface of the housing 420bb, and the outer 420a and 420b are fitted in-slot by these concave and convex portions. .

  The angular ball bearing 84 includes an inner ring 84a, an outer ring 84b, and a plurality of balls 84c provided so as to be able to roll between the inner ring 84a and the outer ring 84b. The angular ball bearing 85 includes an inner ring 85a, an outer ring 85b, and a plurality of balls 85c provided so as to be able to roll between the inner ring 85a and the outer ring 85b. And the angular ball bearings 84 and 85 are opposed to each other in the axial direction as a front combination via an inner ring spacer 86.

The inner rings 84 a and 85 a are fixed to the outer peripheral surface of the rotor 12 while being pressed in the axial direction. Specifically, the step 12c formed on the outer peripheral surface of the rotor 12 is brought into contact with the upper surface of the inner ring 84a, the inner ring retainer 26 is brought into contact with the lower surface of the inner ring 85a, and the inner ring retainer 26 is rotated by a bolt (not shown). 12 is fixed by fastening.
The outer rings 84b and 85b are fixed to the inner peripheral surface of the outer 420a while being pressed in the axial direction. Specifically, a stepped portion 420c formed on the inner peripheral surface of the outer ring 420a is brought into contact with the lower surface of the outer ring 85b, and an outer ring spacer 87 and a web washer 88 are placed in that order on the upper surface of the outer ring 84b. The outer ring presser 28 is fixed to the outer 420a by bolts (not shown) from above the washer 88.

The rotor 12 is fixed integrally with the shaft housing portion 12d, and the shaft housing portion 12d is fitted to the outer peripheral surface of the rotating shaft of the motor 310.
The monopolar resolver 30a is an ABS type outer rotor type resolver, and includes a resolver rotor 18a made of an annular stratified iron core and a resolver stator 20a made of an annular stratified iron core (silicon steel plate). . Resolver stator 20a has a stator core 20ac in which a plurality of stator poles 20ap are formed at equal intervals on the outer periphery of an annular member formed by laminating silicon steel plates, and stator windings 20al wound around each stator pole 20ap. The resolver rotor 18a has an inner circumference that is eccentric with respect to the axial centers of the angular ball bearings 84 and 85, and is disposed to face the stator pole 20ap at a predetermined interval. Therefore, a unipolar resolver signal is output in which the fundamental wave component of the reluctance change is one cycle per revolution of the resolver rotor 18a.

  The multipolar resolver 30i is an INC-type outer rotor type resolver, and includes a resolver rotor 18i made of an annular stratified iron core and a resolver stator 20i made of an annular stratified iron core (silicon steel plate). . Resolver stator 20i has a stator core 20ic in which a plurality of stator poles 20ip are formed at equal intervals on the outer periphery of an annular member formed by laminating silicon steel plates, and a stator winding 20il wound around each stator pole 20ip. The resolver rotor 18i has a plurality of salient pole-like teeth formed at equal intervals in the circumferential direction, and is disposed to face the stator pole 20ip with a predetermined interval. For this reason, a multipolar resolver signal in which the fundamental wave component of the reluctance change is multi-period per rotation of the resolver rotor 18i is output.

The resolver rotors 18a and 18i are arranged at a minute interval via a rotor spacer 42, and are attached to the inner peripheral surface of the rotor 12 by bolts 18b. On the other hand, the stator cores 20ac and 20ic are arranged with a small interval through the stator spacer 44, and are attached to the outer peripheral surface of the inner wall body 420bw by bolts 20b.
A through hole 89 that penetrates from above the resolver stator 20a to the inside of the housing 420bb is formed in the inner wall body 420bw. In addition, a circuit board 90 having a function equivalent to that of the relay device 200 in the first embodiment is provided in the housing 420bb. The resolver stators 20 a and 20 i are connected to the circuit board 90 through the through holes 89. This wiring is pressed by the cable presser 91 above the resolver stator 20a.

The lower surface of the housing 420bb is open, and the outer cover 92 is attached to the open surface. As a result, the circuit board 90 is exposed when the outer cover 92 is removed, which facilitates maintenance. The circuit board 90 is connected to the motor control device 300 in the first embodiment via a communication cable.
On the other hand, the rotor 12, the resolver rotor 18a, so that the thermal expansion coefficient close to 18i, the linear expansion coefficient of 10.0 × 10 ^-6 [/℃]~17.5×10 ^-6 of [/ ° C.] Set to range. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.

Next, the operation of the present embodiment will be described.
When the motor 310 rotates, rotational torque is applied to the shaft housing portion 12d, and the rotor 12 rotates integrally with the shaft housing portion 12d. Then, the resolver 30a, 30i detects a change in reluctance between the resolver rotors 18a, 18i rotating integrally with the rotor 12, and outputs a resolver signal.

In the circuit board 90, a resolver signal is input, the input resolver signal is sampled at a predetermined period, and a signal value obtained by sampling is output as a digital angle signal.
In the circuit board 90, the digital angle signal values of the monopolar resolver signal and the multipolar resolver signal are acquired at the sampling timing, and the rotation angle position is calculated based on the acquired digital angle signal value and the correction data. Then, rotation angle position detection data indicating a highly accurate rotation angle position having these rotation angle positions as components is output.

In the motor control device 300, the motor 310 is controlled based on the rotation angle position detection data.
On the other hand, when the temperature around the bearing rises during driving, the resolver rotors 18a and 18i and the rotor 12 adjacent thereto expand, but the thermal expansion coefficient of the resolver rotors 18a and 18i and the thermal expansion coefficient of the rotor 12 are comparable. Therefore, the degree to which the resolver rotors 18a and 18i are pressed by the rotor 12 is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the change in the AC components Aac, Bac, and Cac in the above equation (1) is reduced.

Further, when a moment load is applied to the resolver device 100, the resolver device 100 tilts around the angular ball bearings 84, 85, but the resolvers 30a, 30i are arranged on the same radial plane as the angular ball bearings 84, 85. Therefore, the gap change of the resolvers 30a and 30i can be reduced.
Further, since the resolvers 30a and 30i and the angular ball bearings 84 and 85 are arranged on the same plane in the radial direction, the height (length in the axial direction) of the resolver device 100 can be reduced.

  Further, when a method such as increasing the preload of the angular ball bearings 84 and 85 is adopted, the gap can be suppressed, but there is a problem that the service life of the angular ball bearings 84 and 85 is shortened. Then, since the gap change is reduced by disposing the resolvers 30a and 30i at positions where the gap change is small, the service life of the angular ball bearings 84 and 85 can be increased.

Thus, in the present embodiment, the resolver device 100 includes the resolvers 30a and 30i and the rotor 12 to which the resolver rotors 18a and 18i are fixed, and the rotor 12 is made of an iron material such as S45C or stainless steel. .
Thereby, even if the temperature around the bearing rises, the degree to which the resolver rotors 18a and 18i are pressed by the rotor 12 is small, so that the change in the gaps of the resolvers 30a and 30i can be reduced compared to the conventional case. A decrease in accuracy due to a temperature change can be suppressed.

Further, in the present embodiment, resolver device 100 incorporates circuit board 90 having the same function as relay device 200 in the first embodiment.
Thereby, since the line length which transmits the resolver signal which is an analog signal can be shortened, the fall of the precision by the influence of noise etc. can be suppressed.
Furthermore, in the present embodiment, resolver device 100 includes angular ball bearings 84 and 85 having inner ring 14a and outer ring 14b, stator 22 supported by inner ring 14a, rotor 12 supported by outer ring 14b, and rotor 12. The resolvers 30a and 30i for detecting the rotational angle positions of the first and second rotation angle positions are arranged, and the resolvers 30a and 30i and the angular ball bearings 84 and 85 are arranged on the same radial plane.

Thus, even when a moment load is applied to the resolver device 100, the resolver 30a, 30i is disposed at a position where the gap change is small. Therefore, the gap change of the resolver 30a, 30i can be reduced, and the accuracy due to the moment load can be reduced. The decrease can be suppressed. Moreover, since the resolvers 30a and 30i and the angular ball bearings 84 and 85 are arranged on the same plane in the radial direction, the height of the resolver device 100 can be reduced. Further, the service life of the angular ball bearings 84 and 85 can be increased as compared with a method of increasing the preload of the angular ball bearings 84 and 85.
In the third embodiment, the rotor 12 corresponds to the fixed member of the first to third aspects.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described.
The present embodiment is different in that the material of the inner ring presser 26 is changed in the first embodiment.

The inner ring pressing 26, a stator core 20 ac, so that the thermal expansion coefficient close to 20Ic, the range of the linear expansion coefficient of ^{10.0 × 10 -6 [/℃]~17.5×10 -6 [} / ℃] Is set. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.

Next, the operation of the present embodiment will be described.
When the temperature around the bearing rises during driving, the stator cores 20ac, 20ic and the inner ring presser 26 adjacent thereto expand, but the thermal expansion coefficient of the stator cores 20ac, 20ic and the thermal expansion coefficient of the inner ring presser 26 are comparable. Therefore, the degree to which the stator cores 20ac and 20ic are pressed by the inner ring presser 26 is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the variation of the DC components Adc, Bdc, and Cdc in the above equation (1) is reduced.

Thus, in the present embodiment, resolver device 100 includes resolvers 30a and 30i, inner wall body 12a to which resolver rotors 18a and 18i are fixed, and inner ring presser 26 to which stator cores 20ac and 20ic are fixed. The inner wall body 12a and the inner ring presser 26 were made of iron material such as S45C or stainless steel.
Thus, even if the temperature around the bearing rises, the degree to which the resolver rotors 18a, 18i are pressed by the inner wall body 12a is small, and the degree to which the stator cores 20ac, 20ic are pressed by the inner ring presser 26 is also small. The gap change of 30i can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.
In the fourth embodiment, the inner ring presser 26 corresponds to the fixed member of the inventions 4 to 6.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described.
The present embodiment is different in that the material of the stator 22 is changed in the second embodiment.

(Including the inner walls body 22a.) The stator 22 is a stator core 20 ac, so that the thermal expansion coefficient close to 20Ic, the linear expansion coefficient of 10.0 × 10 ^-6 [/℃]~17.5×10 ^-6 It is set in the range of [/ ° C]. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.

Next, the operation of the present embodiment will be described.
When the temperature around the bearing rises during driving, the stator cores 20ac and 20ic and the inner wall body 22a adjacent thereto expand, but the thermal expansion coefficient of the stator cores 20ac and 20ic and the thermal expansion coefficient of the inner wall body 22a are comparable. Therefore, the degree to which the stator cores 20ac and 20ic are pressed by the inner wall body 22a is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the variation of the DC components Adc, Bdc, and Cdc in the above equation (1) is reduced.

Thus, in the present embodiment, resolver device 100 includes resolvers 30a and 30i, inner wall body 12a to which resolver rotors 18a and 18i are fixed, and inner wall body 22a to which stator cores 20ac and 20ic are fixed. The inner wall body 12a and the inner wall body 22a were made of an iron material such as S45C or stainless steel.
Thereby, even if the temperature around the bearing rises, the degree to which the resolver rotors 18a, 18i are pressed by the inner wall body 12a is small, and the degree to which the stator cores 20ac, 20ic are pressed by the inner wall body 22a is also small. The gap change of 30i can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.
In the fifth embodiment, the inner wall body 22a corresponds to the fixed member of the inventions 4 to 6.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described.
The present embodiment is different in that the material of the outer 420b is changed in the third embodiment.

(Including the inner walls thereof 420bw.) Outer 420b is, the stator core 20 ac, so that the thermal expansion coefficient close to 20Ic, the linear expansion coefficient of 10.0 × 10 ^-6 [/℃]~17.5×10 ^-6 It is set in the range of [/ ° C]. For example, it is comprised with iron materials, such as S45C, or stainless steel. In addition, when comprising with an iron material, in order to suppress generation | occurrence | production of rust, it is preferable to perform surface treatments, such as low-temperature chromium plating.

Next, the operation of the present embodiment will be described.
When the temperature around the bearing rises during driving, the stator cores 20ac, 20ic and the inner wall body 420bw adjacent thereto expand, but the thermal expansion coefficient of the stator cores 20ac, 20ic and the thermal expansion coefficient of the inner wall body 420bw are comparable. Therefore, the degree to which the stator cores 20ac and 20ic are pressed by the inner wall body 420bw is small. Therefore, the change in the gap between the resolvers 30a and 30i is reduced, and the variation of the DC components Adc, Bdc, and Cdc in the above equation (1) is reduced.

Thus, in the present embodiment, resolver device 100 includes resolvers 30a and 30i, rotor 12 to which resolver rotors 18a and 18i are fixed, and inner wall body 420bw to which stator cores 20ac and 20ic are fixed, The rotor 12 and the inner wall body 420bw were made of an iron material such as S45C or stainless steel.
Accordingly, even if the temperature around the bearing rises, the resolver rotors 18a and 18i are less pressed by the rotor 12, and the stator cores 20ac and 20ic are pressed by the inner wall body 420bw, so the resolvers 30a and 30i are reduced. The gap change can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.
In the sixth embodiment, the inner wall body 420bw corresponds to the fixed member of the inventions 4 to 6.

[Other Embodiments]
In the fourth embodiment, the inner wall body 12a and the inner ring retainer 26 are made of an iron material such as S45C or stainless steel. However, the present invention is not limited to this, and only the inner ring retainer 26 is made of an iron material such as S45C, stainless steel, or the like. It can also be composed of silicon steel. In the case of silicon steel, since the thermal expansion coefficient is the same, the gap change of the resolvers 30a and 30i can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.

In this case, the inner ring presser 26 corresponds to the fixed member of the seventh to ninth aspects.
Moreover, in the said 5th Embodiment, although the inner wall body 12a and the inner wall body 22a were comprised with iron materials, such as S45C, or stainless steel, not only this but only the inner wall body 22a, iron materials, such as S45C, stainless steel, or It can also be composed of silicon steel. In the case of silicon steel, since the thermal expansion coefficient is the same, the gap change of the resolvers 30a and 30i can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.

In this case, the inner wall body 22a corresponds to the fixed member of the inventions 7 to 9.
In the sixth embodiment, the rotor 12 and the inner wall body 420bw are made of iron material such as S45C or stainless steel. However, the present invention is not limited to this, and only the inner wall body 420bw is made of iron material such as S45C, stainless steel, or silicon. It can also be made of steel. In the case of silicon steel, since the thermal expansion coefficient is the same, the gap change of the resolvers 30a and 30i can be further reduced, and the decrease in accuracy due to the temperature change can be further suppressed.

In this case, the inner wall body 420bw corresponds to the fixed member of the seventh to ninth aspects.
Moreover, in the said 1st Embodiment, although the inner wall body 12a was comprised with iron materials, such as S45C, or stainless steel, not only this but the inner wall body 12a can also be comprised with silicon steel. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.

Moreover, in the said 2nd Embodiment, although the inner wall body 12a was comprised with iron materials, such as S45C, or stainless steel, not only this but the inner wall body 12a can also be comprised with silicon steel. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.
Moreover, in the said 3rd Embodiment, although the rotor 12 was comprised with iron materials, such as S45C, or stainless steel, it is not restricted to this, The rotor 12 can also be comprised with silicon steel. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.

  In the fourth embodiment, the inner wall body 12a and the inner ring retainer 26 are made of an iron material such as S45C or stainless steel. However, the present invention is not limited to this, and one or both of the inner wall body 12a and the inner ring retainer 26 are made of silicon. It can also be made of steel. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.

  Moreover, in the said 5th Embodiment, although the inner wall body 12a and the inner wall body 22a were comprised with iron materials, such as S45C, or stainless steel, not only this but one or both of the inner wall body 12a and the inner wall body 22a are silicon. It can also be made of steel. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.

  In the sixth embodiment, the rotor 12 and the inner wall body 420bw are made of an iron material such as S45C or stainless steel. However, the present invention is not limited to this, and one or both of the rotor 12 and the inner wall body 420bw are made of silicon steel. It can also be configured. Thereby, since the coefficient of thermal expansion is the same, the gap change of resolver 30a, 30i can be made still smaller, and the fall of the precision by a temperature change can further be suppressed.

  In the first to sixth embodiments, the unipolar resolver 30a and the multipolar resolver 30i are provided. However, the present invention is not limited to this, and the unipolar resolver 30a can be used alone. It can be configured only from the pole resolver 30i, or can be configured from an ABS / INC integrated resolver that outputs a unipolar resolver signal and a multipolar resolver signal.

  In the first and fourth embodiments, the resolver rotors 18 a and 18 i are attached to the outer peripheral surface of the inner wall body 12 a of the rotor 12, and the resolver stators 20 a and 20 i are attached to the inner peripheral surface of the inner ring presser 26. However, the present invention is not limited to this, and the resolver stators 20 a and 20 i may be attached to the outer peripheral surface of the inner wall body 12 a of the rotor 12 and the resolver rotors 18 a and 18 i may be attached to the inner peripheral surface of the inner ring presser 26. Similarly, in the second, third, fifth and sixth embodiments, the positions of the resolver rotors 18a and 18i and the resolver stators 20a and 20i can be reversed.

  In the first, second, fourth and fifth embodiments, the resolvers 30a and 30i and the cross roller bearing 14 are arranged on the same radial plane in the order from the radial inner side. The arrangement order of the resolvers 30a and 30i and the cross roller bearing 14 is not limited to this, and may be arbitrary. Similarly, in the third and sixth embodiments, the order of arrangement of the resolvers 30a and 30i and the angular ball bearings 84 and 85 can be arbitrarily set.

  Moreover, in the said 1st, 2nd, 4th and 5th embodiment, although the cross roller bearing 14 was applied, it is not limited to this, A four-point contact ball bearing, an angular ball bearing, a deep groove ball A bearing, a cylindrical roller bearing, a tapered roller bearing, or the like may be applied. In this case, it is preferable to employ a rolling bearing that can simultaneously receive a moment load, an axial load, and a radial load. An example of such a rolling bearing is a four-point contact ball bearing.

  In the third and sixth embodiments, the angular ball bearings 84 and 85 are applied. However, the present invention is not limited to this. Four-point contact ball bearings, cross roller bearings, deep groove ball bearings, cylindrical rollers A bearing, a tapered roller bearing, or the like may be applied.

2 is a sectional view of the resolver device 100 in the axial direction. FIG. It is a block diagram which shows the structure of a control system. 2 is a sectional view of the resolver device 100 in the axial direction. FIG. 2 is a sectional view of the resolver device 100 in the axial direction. FIG. 2 is a sectional view of the resolver device 100 in the axial direction. FIG. 2 is a sectional view of the resolver device 100 in the axial direction. FIG. It is sectional drawing of the axial direction of the conventional rotational drive apparatus 400. FIG. 3 is a graph showing a position detection error of a resolver 30.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Resolver apparatus 12 Rotor 12d Shaft accommodating part 14 Cross roller bearing 14a, 84a, 85a Inner ring 14b, 84b, 85b Outer ring 14c Cross roller 84c Ball 30a, 30i, 30 Resolver 18a, 18i, 18 Resolver rotor 20a, 20i, 20 Resolver stator 20ac, 20ic, 20c Stator core 20ap, 20ip, 20p Stator pole 20al, 20il, 20l Stator winding 22 Stator 12a, 22a Inner wall body 12b, 22b Outer wall body 26 Inner ring retainer 28 Outer ring retainer 84, 85 Angular contact ball bearing 89 Through hole 90 Circuit Substrate 92 Outer cover 42, 44, 86, 87 Spacer 420a, 420b Outer 420bb Housing 420bw Inner wall 12c, 22c, 420c Step 200 Relay device 50 Oscillator 52 Amplifier 5 4 switch 56a, 56b current / voltage converter 58a, 58b 3/2 phase converter 60 analog switch 62 phase shifter 64 RDC
66 Memory 68 CPU
70 Control Signal Input / Output Unit 72 Position Detection Signal Output Unit 74 Abnormality Detection Signal Output Unit 300 Motor Control Device 310 Motor 400 Rotation Drive Device 420 Housing Inner

Claims (9)

A stator core having a plurality of poles formed on the inner periphery or outer periphery of the annular member, a resolver stator having a stator winding wound around the poles of the stator core, and a resolver rotor disposed to face the poles of the stator core. A resolver device comprising: a resolver in which reluctance between the resolver rotor and the resolver stator changes according to a position of the resolver rotor; and a fixed member to which the resolver rotor is fixed;
The resolver device, wherein the fixed member is made of a material having a thermal expansion coefficient that is the same as or close to that of the resolver rotor. In claim 1,
The resolver device is characterized in that the resolver rotor is made of silicon steel, and the fixed member is made of iron or stainless steel. In claim 1,
The resolver rotor is composed of silicon steel, wherein said a linear expansion coefficient of the fixing member is ^{10.0 × 10 -6 [/℃]~17.5×10 -6 [} / ℃] Resolver device. In any one of Claims 1 thru | or 3,
A second fixed member to which the stator core is fixed;
The resolver device, wherein the second fixed member is made of a material having a thermal expansion coefficient that is the same as or close to that of the stator core. In claim 4,
The resolver device, wherein the stator core is made of silicon steel, and the second fixed member is made of iron or stainless steel. In claim 4,
The stator core is composed of a silicon steel, and wherein the linear expansion coefficient of the second fixation member is ^{10.0 × 10 -6 [/℃]~17.5×10 -6 [} / ℃] Resolver device. A stator core having a plurality of poles formed on the inner periphery or outer periphery of the annular member, a resolver stator having a stator winding wound around the poles of the stator core, and a resolver rotor disposed to face the poles of the stator core. A resolver device comprising: a resolver in which reluctance between the resolver rotor and the resolver stator changes according to a position of the resolver rotor; and a fixed member to which the stator core is fixed;
The resolver device is characterized in that the fixed member is made of a material having a coefficient of thermal expansion that is the same as or close to that of the stator core. In claim 7,
The resolver device, wherein the stator core is made of silicon steel, and the fixed member is made of iron or stainless steel. In claim 7,
The stator core is composed of silicon steel, a resolver, wherein the a linear expansion coefficient of the fixing member is ^{10.0 × 10 -6 [/℃]~17.5×10 -6 [} / ℃] apparatus.

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