JPH02183124A - Rotary encoder built-in type motor - Google Patents

Abstract

PURPOSE:To facilitate an assembling work with a reduction in the number of parts by forming a winding pattern for generating a rotating force and an encoder pattern for detecting a value of rotation on one sheet of a disc-shaped rotor. CONSTITUTION:A disc-shaped rotor R is fixed at a rotor support 5a with a large diameter formed at the center of a rotating shaft 5. The rotor R has a winding pattern 6 for generating a rotating force formed at radius-wise center thereof and an encoder pattern 7 for detecting a rotation value at a part of an outer circumference. Then, starters 9a, 10a and 9b and 10b for generating a line of magnetic force are arranged facing the pattern 6 while an encoder sensor section 11 at a position facing the pattern 7. Thus, the formation of the patterns 6 and 7 on one sheet of the rotor R reduces the number of parts. This facilitates work of assembling a motor and axial dimensions of the motor as a whole little increase as compared with the case of incorporating none of a rotary encoder E.

Description

DETAILED DESCRIPTION OF THE INVENTION A1 Object of the Invention (1) Industrial Application Field The present invention relates to a motor used for micro-rotating an optical element in an optical machine such as a spectrophotometer in a Sunagawa unit. In particular, the present invention relates to a motor equipped with means for detecting the amount of rotation of a rotating shaft.

(2) Conventional technology In general, in optical machines such as spectrophotometers, optical elements such as diffraction gratings, prisms, and reflectors are manufactured in Sunagawa units (10 to 0.5
It is necessary to rotate 40 to 60 degrees with an accuracy of 1 second. The minute rotational drive of the optical element is normally performed by a motor, but as shown in FIG.
When making minute rotations, there are a single sine bar system using a sine bar mechanism 03, a system that combines a motor 01 such as a pulse motor and a burying machine 04 as shown in FIG. A method is used in which the rotation of a pulse motor 01 driven in microsteps is driven via a speed reduction mechanism 05 using a special belt or the like.

The sine bar single type shown in Figure 10 has many large, precision machined parts and is expensive.Also, the adjustment is complicated, which causes high prices, and the disadvantages include slow operation speed and time required for spectroscopy. was there.

In addition, although the system that combines the motor 01 and the reduction mechanism 04 shown in Fig. 11 allows a large rotation angle, the accuracy is low due to the backlash of the reduction mechanism 04, and the accuracy cannot be achieved unless the reduction ratio is increased. This has the disadvantage that the operating speed is slow and spectroscopy takes time.

In order to overcome this drawback, it is possible to reduce the reduction ratio somewhat and use a microstep-driven pulse motor. was causing a decline in

In addition, although the method of driving the rotation of the motor 01 through a special belt reduction mechanism 05 as shown in Fig. 12 is inexpensive, it is said that the accuracy tends to decrease due to fluctuations in the length of the belt due to temperature expansion. There was a problem. Also, this 12th
The one shown in the figure has a large reduction ratio due to its structure, so a pulse motor that is driven by microsteps is generally used. There was a drawback that the motor could not be driven, and even if the motor had a nominal division of 100, it could only be used in actual divisions of 30 to 50.

By the way, the rotation angle can be detected by connecting a rotary encoder to the motor and extracting the rotation angle as a coded signal.
Accurate control has traditionally been a common practice.

- Several structural methods have been considered when connecting a rotary encoder to a motor for boat fishing.

Figure 13 shows a conventional type in which the motor O1 and the rotary encoder 06 are connected by a coupling 07.The coupling 07 is of a metal bellows type or a precision diaphragm type, but the friction of the bearing and the coupling There was a slight decrease in accuracy due to stiffness.

In FIG. 14, a rotary encoder 36 is fixed to a motor 32, and misalignment between the axes of the two can be avoided.

FIG. 15 is described in Japanese Patent Application Laid-Open No. 62-290334, in which an encoder sensor section 09 having a light emitting section and a light receiving section is provided on a stator 08, and a pattern plate O1l is provided on a magnet rotor 010. In addition, FIG. 16 is described in Japanese Patent Application Laid-Open No. 58-22570, in which a reflective pattern 013 is provided on the outer surface of a rotor 012 of a winding, and the reflective pattern 013 is opposed to the rotor 012. An encoder sensor section 014 having a light emitting section and a light receiving section is provided at the position.

(3) Problems to be Solved by the Invention The above-mentioned motor and rotary encoder connection structures all have problems in terms of miniaturization, simplification of structure, and ease of assembly.

The present invention has been made in view of the above-mentioned circumstances, and has devised a structure for incorporating a rotary encoder into a motor used as a micro-rotation drive device for optical elements, etc., to simplify the structure and facilitate assembly. The challenge is to make it possible to make the device thinner.

B1 Structure of the Invention (1) Means for Solving the Problems In order to solve the above problems, the rotary encoder built-in motor of the present invention has a printed winding pattern formed in the center in the radial direction, and a printed winding pattern on the outer periphery. A disc-shaped rotor on which an encoder pattern for detecting the amount of rotation is formed is fixed to a motor rotating shaft, and a stator for generating lines of magnetic force is disposed opposite to the winding pattern, and a stator is disposed at a position opposite to the encoder pattern. It is characterized by the provision of an encoder sensor section.

(2) Function The motor with a built-in rotary encoder according to the present invention having the above-described configuration has a winding pattern for generating rotational force and an encoder pattern for detecting the amount of rotation on a single disc-shaped rotor. This reduces the number of parts and facilitates assembly. Further, the axial dimension of the entire motor hardly increases compared to the case where the rotary encoder disk is not incorporated.

(3) Embodiment A first embodiment of a motor with a built-in rotary encoder according to the present invention will be described below with reference to the drawings.

Fig. 1 is a front cross-sectional view of the first embodiment of the DC motor M with a built-in rotary encoder and an optical element of a spectroscopic analyzer attached to its rotating shaft, and Fig. 2 is a view from the arrow ■ in Fig. 1. Fig. 3 is a plan view of the front surface of the rotor of the DC motor of the same example, Fig. 4 is a plan view of the back side of the rotor, and Figs. FIG. 2 is a diagram showing an example of a spectroscopic analysis device using a DC motor with a built-in encoder.

In Figure 1.2, there are multiple screw holes 1a for fixing around the periphery.
The base 1 has a circular shape in plan view, and a lower bearing 2 is supported at the center thereof. Said base 1
The upper surface of the disc-shaped top wall 4 supports the upper bearing 3 in the center.
a and a cylindrical side wall 4b at its outer periphery.

A rotary shaft 5 is supported by the lower bearing 2 and the upper bearing 3, and a large diameter rotor support portion 5a is formed in the center of the rotary shaft 5. A disk-shaped rotor R is fixed to this rotor support portion 5a.

The disk-shaped rotor R is constituted by a transparent disk made of glass, silicon, quartz, etc., having conductor patterns as shown in FIGS. 3 and 4 on its front and back surfaces. In this way, since the rotor R is transparent, its surface diagram (
The winding pattern on the other side should also be visible in the back view (Figure 3) and back view (Figure 4), but in order to make the figures easier to read, the winding pattern on the other side is omitted in Figures 3.4. It is. As shown in Fig. 3.4, the disk-shaped rotor R has a winding pattern 6 for generating rotational force formed in the center in the radial direction, and a winding pattern 6 for detecting the amount of rotation in a part of the outer periphery. An encoder pattern 7 is formed. These patterns 6,7 are formed by etching a suitable metal film, such as copper or chromium. In FIGS. 3 and 4, wiring portions extending in the radial direction are formed in the left side portion 6L and right side portion 6i of the winding pattern 6, and in this winding pattern 6, current flows from the positive terminal 6a on the surface thereof. It flows to the through-hole terminal 6b, and on the back side, it flows from the through-hole terminal 6b to the negative terminal 6C. Therefore, among the wiring portions extending in the radial direction of the winding pattern 6, the current l flows from the inside to the outside in the left side portion 6L, and the current i flows from the outside to the inside in the right side portion 6II.
flows.

In FIGS. 1 and 2, the base l and the casing 4 support arch-shaped magnets 9a, 9b and loa, 10b in FIG. . The rotor R is placed between these magnets 9a, 10a and 9b, 10b which are placed opposite to each other. The magnets 9a and 10a are arranged to sandwich the left side portion 6L of the winding pattern 6 between them, and the magnetic lines of force H8 are directed upward from below as shown in FIG.
Further, the magnets 9b and 10b are arranged to sandwich the right side portion 6R of the winding pattern 6 between them, and the direction of the lines of magnetic force H is downward from above as shown in FIG.

Further, the encoder pattern 7 formed on the outer circumferential portion of the rotor R has, for example, an entire circumference (3600) of 2160
The pattern 7 is divided into approximately 0 degrees, and the pattern 7 is provided in a range of approximately 60° to 90° (the range in which the rotating shaft 5 is actually rotated during use).

An encoder sensor section 11 having a light emitting section 11a and a light receiving section 11b is fixedly supported on the base 1 by screws. The light emitting section lla and the light receiving section 11
b is arranged at a position sandwiching the outer peripheral portion of the rotor R on which the encoder pattern 7 is formed. The rotor R
encoder pattern 7 and encoder sensor section 11
A rotary encoder E is constructed from the following.

A holder 12 is fixed to the upper end of the rotation shaft 5, and an optical element 13 such as a grating mirror is supported on the holder 12.

Moreover, as shown in FIG. 1, two of the plurality of external connection cords 11! ! 1 and I! , passes through the opening of the casing 4, is wound around the rotating shaft 5 with a margin, and then connected to the connecting terminals T, , T2 of the rotating shaft (only T1 is shown)
is soldered to. And its connection terminals TI, T
2 is connected to the plus terminal 6a and minus terminal 6b of the winding pattern 6. As described above, when power is supplied to the winding pattern 6 without using brushes and slip rings, the frictional resistance of the rotating shaft 5 decreases, and the DC motor M
It becomes possible to perform rotation control with higher precision.

Further, a plurality of other connection cords Ili are connected to the encoder sensor section 11.

Next, an example of a spectroscopic analyzer using the DC motor M with built-in rotary encoder will be described with reference to FIG. In this spectrometer, a direct current motor M is driven by a direct control method.

The motor driver 21 outputs an output voltage e proportional to the input signal et. The DC motor M is driven by this output voltage e1. Then, the rotating shaft 5 of the DC motor M
The rotational angular velocity of (that is, the rotational angular velocity of the rotor R formed with the winding pattern 6 and the encoder pattern 7) is approximately proportional to the input signal e.

At this time, the angular position of the optical element 13 is read by the low-resolution encoder E and the pulse counter 22, and is further divided into 4 to 10 parts and input to the computer 23.

At this time, the light emitted from the light emitting and light receiving device 24 of the spectrometer and reflected from the optical element 13 is detected by the light emitting and light receiving device 24 and input to the computer 23 .

In this way, the angular position signal of the optical element 12 (output signal of the pulse counter 22) and the amount of reflected light from the optical element 13 at that angular position are simultaneously input to the computer 23, and the angular position signal represents the wavelength of the reflected light from the optical element 13 that is input to the combination z-tar 23 at that time.

Therefore, the computer 23 outputs the spectrum of the light output by the light emitting and light receiving device 24.

Next, another example of a spectroscopic analyzer using the rotary encoder built-in DC motor M will be described with reference to FIG. In this spectrometer, a DC motor M is driven by a digital feedback control method. Note that in FIG. 6, components having the same functions as those in FIG. 5 are given the same reference numerals and redundant explanations will be omitted.

The number N of digital pulses corresponding to the desired rotation angle and the number N of pulses read by the pulse counter 22 (that is, the angular position of the optical element work 2) are input to the control circuit 25. Then, the control circuit 25 outputs an analog signal e proportional to N, -NJ to the motor driver 21. The motor driver 21 receives the human power signal e! output voltage e proportional to
Output. The DC motor M is driven by this output voltage e11. The angular position of the rotating shaft 5 of the DC motor M, that is, the angular position of the optical element 13 is read by the rotary encoder E and the pulse counter 22 and inputted to the computer 23, as well as to the control circuit 2 described above.
5 as a feedback signal N. Therefore, the DC motor M stops at the angular position corresponding to the input signal N.

The embodiment of the spectroscopic analyzer shown in FIG.
Similar to the spectroscopic analyzer shown in the figure, the computer 2 analyzes the spectroscopic spectrum of the light output by the light emitting and receiving device 24.
3 outputs.

Next, a second embodiment of the rotary encoder built-in DC motor M of the present invention will be described with reference to FIG. 7 and FIGS. 8 and 9. In FIGS. 7 and 8-9, components having the same functions as those in FIGS. 1 and 3.4 are designated by the same reference numerals, and redundant detailed explanations will be omitted.

In FIG. 7, the casing 4 is made of a magnetic member, and the casing 4 is provided with a through hole 4c through which the rotating shaft 5 passes. In addition, in the casing 4,
Protrusions 4d and 4e for reinforcing magnetic lines of force are formed at positions facing magnets 9a and 9b supported by base 1.

Further, an upper bearing support member 14 is supported on the upper surface of the casing 4, and the rotation shaft 5 is supported by the upper pivot bearing 3 supported by the upper bearing support member 14 and the lower pivot bearing 2 supported by the base 1. is rotatably supported.

The disc-shaped rotor R shown in FIGS. 8 and 9 has winding patterns 6 as shown in FIGS. 8 and 9 formed on its front and back surfaces. In this winding pattern 6, current flows from the positive terminal 6a to the through-hole terminals 6b, 6b on the front surface, and through-hole terminals 6-b, 6b on the back surface.
6b to the negative terminal 6c. Therefore, the eighth
．． In FIG. 9, the left side portion 6L and the right side portion 6. The left side portion 6. has a radially extending conductor portion formed thereon. In this case, the current i flows from the inside to the outside, and in the right side portion 68, the current i flows from the outside to the inside.

The second embodiment of the DC motor M with a built-in rotary encoder shown in FIGS. 7 to 9 described above is similar to the first embodiment shown in FIGS. 1 to 4 described above. Used in the spectrometer shown.

Although the embodiments of the rotary encoder built-in motor according to the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and there is no deviation from the present invention as set forth in the claims. However, various design changes can be made.

For example, the encoder pattern 7 can be either incremental or absolute. Further, the winding pattern 6 can adopt various patterns that can generate rotational force, and
It is also possible to form it on only one side of the rotor R instead of on both the front and back sides.

Furthermore, by supplying power to a suitable winding pattern 6 using brushes and slip rings, it is also possible to rotate the motor continuously. The rotor R is constructed from a disc made of an opaque insulating material such as ceramic, and
It is also possible to form an encoder pattern on either the front or back surface of the rotor R, and to arrange the light emitting section and light receiving section of the encoder sensor section on the side on which the encoder pattern is formed.

C1 Effects of the invention DC motor M with built-in rotary encoder of the invention described above
According to the above, since a winding pattern for generating rotational force and an encoder pattern for detecting the amount of rotation are formed on a single disc-shaped rotor, the number of parts is reduced. Therefore, the motor assembly work becomes easier. Further, the axial dimension of the entire motor hardly increases compared to the case where the row encoder is not incorporated.

Therefore, it is possible to obtain a rotary encoder built-in motor that is thin and easy to assemble.

4. Explanation of the hour wheel on the [ff1 side] Fig. 1 is a front cross-sectional view of the first embodiment of the motor with a built-in rotary encoder according to the present invention, in which an optical element is attached to the rotating shaft, and Fig. 2 is a plan view thereof. FIG. 3 is a front view of the rotor of the same embodiment, FIG. 4 is a back view thereof, and FIG. 5 is a DC motor with a built-in rotor encoder of the first embodiment. A diagram showing an example of a spectroscopic analysis device using
FIG. 6 is a diagram showing another example of a spectroscopic analyzer using the motor with a built-in row encoder according to the first embodiment, and FIG. 7 shows the rotation of the second embodiment of the motor with a built-in row encoder according to the present invention. FIG. 8 is a front view of the rotor of the second embodiment, FIG. 9 is a back view thereof, and FIGS. 10 to 12 are views of a conventional rotary drive device for an optical element. 13 to 16 are explanatory diagrams of a conventional connection structure between a motor and a rotary encoder.

4d, 4e, 9a, 9b, 10a, 10b - Stator, 5... Rotating shaft, 6... Winding pattern, 7...
Encoder pattern for detecting rotation amount, M...Motor, R...Rotor Fig. 1 Fig. 2 Fig. 11 Fig. 7 Fig. 8 Fig. 13

Claims (1)

[Claims] A disc-shaped rotor, which has a printed winding pattern formed in the center in the radial direction and an encoder pattern for detecting rotation amount on the outer periphery, is fixed to the motor rotation shaft, and magnetic field lines are formed opposite to the winding pattern. A stator for generation is installed,
A motor with a built-in rotary encoder, characterized in that an encoder sensor section is disposed at a position facing the encoder pattern.