JP4664491B2 - Encoder and mounting method of encoder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an encoder that detects a displacement amount, a rotation amount, and a rotation speed of a measured object that is a rotating body such as a motor. In particular, the encoder unit is provided to a user, and the user assembles the encoder unit to the measured object. The present invention relates to a kit-type encoder and a mounting method thereof.
[0002]
[Prior art]
The rotary encoder converts a mechanical rotational displacement amount into an electric signal, amplifies it, and outputs it. Among them, an optical rotary encoder (hereinafter simply referred to as an encoder) is a slit plate unit that extracts a mechanical rotational displacement, and converts the displacement into an electrical signal and outputs it.
[0003]
There are various types of encoder structures, and there is a kit-type encoder in which a slit plate unit and an encoder unit are separately provided to a user and the user assembles the slit plate unit and the encoder unit. This kit type encoder has only the minimum functional part of the encoder for the purpose of cost reduction and space saving.
[0004]
A configuration example of the kit type encoder is shown in FIG. In FIG. 10, a circuit board 17 is fixed to a device under test 2 such as a motor via a fixing base 1 fixed by a fixing screw 15. An electrical component 18 and a light receiving element 22 are mounted on the circuit board 17. In addition, a fixed slit 23 and a light emitting element 21 are arranged via a code plate 24 at a position facing the light receiving element 22 attached to the fixed base 26 on the DUT 2. Therefore, the light emitted from the light emitting element 21 is input to the light receiving element 22 through the slit of the fixed slit plate 23 and the slit of the code plate 24. Then, the rotation of the shaft 11 causes light to be input to the light receiving element according to a predetermined pattern of slits provided on the code plate 24, and an electrical signal (code pulse) corresponding to the rotation is generated.
[0005]
Such a kit-type encoder is not provided with a rotating shaft and a bearing (and a cover) by being attached to a rotating body that is the device under test 2, for example, a counter-load side shaft end opposite to the output shaft of the motor. In other words, the function as an encoder is exhibited using the other functional component.
[0006]
By the way, the kit type encoder is assembled in a manufacturing process, once the slit plate unit and the encoder unit are assembled on a dedicated jig, checked for function, and then disassembled and provided to the user in a disassembled unit state. . A user who has purchased a kit-type encoder can function as an encoder by assembling it on a rotating shaft of an object to be measured (for example, a motor).
[0007]
Among the performances of the encoder, the accuracy of the output signal waveform is the most important performance. This accuracy is
(1) The rotational accuracy of a rotating body (for example, a motor shaft).
(2) Rotation to detect it and accuracy of the slit of the fixed slit plate itself.
(3) Assembly accuracy of the slit plate unit and the encoder unit to the rotating body.
(4) Detection accuracy of the slit plate unit.
(5) Accuracy of conversion to electrical signals.
Etc. appear in combination.
[0008]
For this reason, in order to obtain the desired accuracy,
In (1), it is important that the accuracy managed by the user is within the required range (hereinafter referred to as the standard), but the solution is easy in view of the current general processing technology.
[0009]
(2) is required to be within the standard range with respect to the accuracy of the slit and the accuracy of the peripheral components, but can be solved by a general technique.
[0010]
(4) and (5) can be solved by a general technique as in (2).
[0011]
In the case of a kit-type encoder, (3) is the most problematic.
[0012]
This is a problem that can be solved on the manufacturer side, but for general users who are not familiar with the structure and characteristics of the encoder, it is necessary to have a technique for assembling the encoder when assembling it on the object to be measured such as a motor. This is because the assembly accuracy greatly depends on the signal waveform accuracy.
[0013]
Since the encoder manufacturer has assembled it once and confirmed its function as an encoder, there is no problem if it can be disassembled and reproduced as it is, but it is technically difficult because it requires considerable accuracy. There are many points.
[0014]
In order to solve this problem, the following methods have generally been taken.
[0015]
In order to position the encoder unit, the encoder mounting surface of the motor is generally provided with a convex shape, and a concave shape (usually referred to as “inlay”) is provided on the opposite encoder side. Centering has been performed by combining them. However, in recent years, the demand for accuracy has increased, and it is difficult to reproduce the accuracy of the encoder with commonly used fitting accuracy (for example, hole H7, shaft h7, etc.), and higher accuracy is required. There were many problems in terms of cost and so on.
[0016]
An encoder having a structure as shown in FIGS. 11A and 11B is also used. 11A is a side view and FIG. 11B is a plan view. In the figure, a circuit board 1 b is attached to a support column 1 a of a main body 1. In the space in the main body 1 and the circuit board 1b, a code plate 24 attached to the shaft 27 of the device under test 2 via a boss 25 is disposed. In the drawing, a light emitting element, a light receiving element, and the like are omitted.
[0017]
Some encoders having such a configuration are assembled on a flat surface without using a spigot and take a method of adjusting the position of the encoder unit. However, this requires adjustment man-hours and proficiency on the user side, making adjustment work difficult. Further, since two or more screws are used for mounting the encoder body 1 and the screwing direction is upward, that is, from a direction parallel to the rotation shaft 27 of the object to be measured, a screwdriver is inserted when screwing. There is a problem that it is necessary to secure a space, and the size of the code plate 24 cannot be made larger than the screwed portion.
[0018]
Furthermore, a method using a taper and a boss provided in the encoder body as described in, for example, Utility Model Registration No. 1614430 and JP-A-6-3163 is also being studied.
[0019]
However, since the encoder body is still fixed with two or more screws, it is not sufficient to simplify the mounting process. Moreover, although simplified, a process for positioning is required, and a structure capable of simpler attachment has been desired.
[0020]
[Problems to be solved by the invention]
An object of the present invention is to provide an encoder that can be positioned and assembled easily and reproducibly with a relatively simple structure, and that can be more highly accurate than a conventional structure, and an attachment method thereof.
[0021]
[Means for Solving the Problems]
That is, the above object can be achieved by the following configuration.
(1) An encoder in which an encoder body (1) is attached to a device under test (2),
The encoder mounting portion of the object to be measured (2) has an inlay fitting portion (2a) formed in a concave shape,
On the measured object mounting side of the encoder body (1), the encoder main body (1) has an inlay insertion portion (1d) that can be inserted into the inlay fitting portion and can be fitted to the measured object.
This spigot insertion part (1d) has a diameter expanding means that can be firmly fixed to the spigot fitting part (2a) by expanding at least part of the diameter formed at the lower part of the encoder body ,
The diameter expanding means cuts out a part of the spigot insertion portion (1d) having the escape hole (13) of the rotating shaft (27) of the object to be measured into a C shape, and this notch portion (12, 12a). Encoder that expands the diameter by expanding .
(2) The encoder according to (1), wherein the diameter expanding means is operated by a force applied via a screw (15).
(3) The encoder according to (1) or (2), wherein the diameter expanding means is operated by a force applied from a direction perpendicular to the rotation axis.
(4) The encoder according to any one of (1) to (3), wherein the inlay fitting portion is formed in a reverse taper shape.
(5) An encoder attachment method in which the encoder body is attached to a device under test,
The encoder mounting portion of the object to be measured has an inlay fitting portion formed in a concave shape, and the measuring object mounting side of the encoder body has an inlay insertion portion capable of expanding at least a part thereof. Have
This spigot insertion part is a C-shape formed in the lower part of the encoder body and having a clearance hole for the rotating shaft of the object to be measured, with a part of the spigot insertion part cut out.
An encoder mounting method in which the spigot insertion portion is inserted into the spigot fitting portion and the diameter thereof is expanded to firmly fix the spigot fitting portion to the spigot fitting portion.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
An encoder according to the present invention is an encoder in which an encoder body is attached to an object to be measured, and the encoder attachment portion of the object to be measured has an inlay fitting portion formed in a recessed shape, The measuring object mounting side has an inlay insertion portion that can be inserted into the inlay fitting portion and can be fitted to the object to be measured, and this inlay insertion portion can be strengthened by expanding the diameter of at least a part thereof. It has a diameter-expanding means that can be fixed to the spigot fitting portion.
[0023]
In this way, by providing a spigot fitting part formed in a concave shape on the measured object side, and inserting the spigot insertion part of the encoder into this spigot fitting part, expanding the diameter and fixing it, Installation work is very easy and very high installation accuracy can be achieved. It is also possible to further improve the accuracy of the encoder.
[0024]
That is, the spigot fitting portion and the spigot insertion portion only need to have a play (play) that can be easily attached, and both can be positioned with a certain degree of accuracy. And since it fixes by expanding a spigot insertion part, while being able to fix to a spigot fitting part very firmly, there is very little position shift and a high positioning accuracy is securable. Moreover, since the diameter expansion operation can be normally performed with one screw, the space for mounting is reduced, and the working efficiency is improved. For this reason, it becomes possible to enlarge a slit board to the magnitude | size close | similar to the magnitude | size of an encoder main body, and the measurement precision of an encoder can also be improved.
[0025]
Next, the encoder of the present invention will be described in more detail with reference to the drawings. 1 to 3 are views showing a configuration example of a kit type encoder unit according to an embodiment of the present invention. FIG. 1 is a front view, FIG. 2 is a side view, and FIG. 3 is a cross-sectional view taken along line XX ′ of FIG. It is an arrow view.
[0026]
1 to 3, a light emitting element (not shown) or the like is attached to the main body 1 having a substantially circular outer peripheral shape. Further, a circuit board 1b having a light receiving element, an electronic component, and the like is attached via a support column 1a. Inside the structure formed by the main body 1 and the circuit board 1b, a code plate 24 attached to the shaft 27 of the DUT 2 via the boss 25 is disposed. The code plate 24 is provided with a light emitting element, a light receiving element and the like with the code plate 24 therebetween.
[0027]
An inlay insertion portion 1 d is formed at the lower portion (bottom portion) of the main body 1. The spigot insertion portion 1d has a notch portion 12 in which a clearance hole 13 of a shaft 27 is formed and a portion of a donut shape (O-shape) is substantially notched. Accordingly, the spigot insertion portion 1d has a C-shape.
[0028]
In this example, the notch portion 12 has a tapered portion 12a at its upper portion as a diameter expanding means, and the screw 15 is tightened by a screw 15 disposed in a screw hole in the notch portion 12 and a wedge washer 15a. It is designed to expand the diameter. That is, the force for expanding the diameter acts from a direction parallel to the shaft 27, and this is converted into a force in a right angle direction by the taper portion 12a and the wedge-shaped washer, and the notch portion 12a is spread to expand the inlay insertion portion 1d. Expand the diameter. In addition, since the magnitude | size of the notch part 12a which the screw | thread 15 arrange | positioned at the notch part 12a is expanded by diameter expansion operation | movement is slight, the relationship between a screw and a screw hole is hold | maintained after diameter expansion. Further, in this example, in order to facilitate the diameter expansion operation, the portion separated from the main body 1 by the slit portion 1c is increased.
[0029]
Thus, since it fixes by diameter-expansion operation, it is not necessary to carry out the screw hole process to a to-be-measured object, and the process and shape of a to-be-measured object can also be simplified.
[0030]
Further, a fitting portion 2 a that can accommodate the spigot insertion portion 1 d of the encoder body 1 is formed around the rotating shaft 27 of the rotating body 27 that performs a rotating operation of the device under test 2, such as a motor or an engine. For example, the fitting portion 2a may be formed in a cylindrical shape as shown in FIG. 4, or may be formed in a reverse taper shape as shown in FIG. By forming an inverse taper, the encoder can be fixed more firmly. In this case, it is more effective that at least the inlay insertion portion 1d of the encoder has a shape along the reverse tapered portion. The taper angle is not particularly limited, but usually about 0.05 to 0.5 ° is sufficient. In addition, although the depth of an inlay fitting part also depends on the magnitude | sizes of an encoder etc., Preferably it is about 1-5 mm.
[0031]
The gap between the fitting portion 2a before the diameter expansion and the spigot insertion portion 1d may be of a size that allows the spigot insertion portion 1d to be inserted relatively easily and that can fix the encoder by the diameter expansion operation. Specifically, although it depends on the size of the spigot insertion portion 1d, positioning can be performed with twice the accuracy of the conventional tolerance width (hole H7).
[0032]
The shape of the fitting portion 2a, the spigot insertion portion 1d, or the encoder main body does not necessarily have to be a circular shape, and the spigot insertion portion 1d accommodated in the fitting portion 2a by the diameter expansion or expansion operation is used. Any shape that can be fixed is acceptable. In addition, these shapes are usually shapes that are regulated by the object to be measured, or circular shapes, or shapes in which the outer shape portion forms part of an arc.
[0033]
The inlay insertion portion 1d may be configured as shown in FIG. 6, for example, in addition to the configuration as described above. In this example, the diameter-expanding screw 15b disposed in the notch 12 as the diameter-expanding means is a set screw (blurred screw) and is tightened from the lateral direction, that is, the direction perpendicular to the rotation axis. That is, by tightening the screw from one side of the notch portion 12, the screw that contacts the other surface of the notch portion 12 is further pushed in, and as a result, the gap of the notch portion 12 is pushed. The spigot insertion part 1d is expanded in diameter. That is, the force for expanding the diameter acts directly from the direction perpendicular to the shaft 27. The screw 15b does not need to be a set screw when there is sufficient space or the like, and a normal screw may be used.
[0034]
In this way, by making the fixing (diameter expanding) screw operable from the side, a space for operating the screw from above becomes unnecessary, and as shown in FIG. It can be made large, and can be enlarged up to the outer shape of the encoder main body or close to the support pillar 1a. As a result, the accuracy (resolution) of the encoder can be further improved. For example, a conventional encoder having an outer diameter of 35 mm and a maximum of 1250 P / R is 20% up to about 1570 P / R. The above can also improve the accuracy.
[0035]
The inlay insertion portion 1d may further be configured as shown in FIG. In this example, a diameter-expanding screw 15 c arranged in the notch 12 as a diameter-expanding means is inserted into a screw hole formed in the DUT 2. The other configuration is the same as the configuration of expanding the diameter by tightening the screw 15c with the screw 15c and the wedge-shaped washer 15a as shown in FIGS. In this way, by attaching the diameter expansion screw 15c to the screw hole formed in the DUT 2, the diameter expansion and fixing screws can be used together, and can be fixed more firmly. In these examples, a screw is used as a means for applying a force for expanding the diameter. However, as long as a force capable of expanding the notch portion can be applied, the screw need not be limited to a screw, and a wedge-shaped pin is used. Etc. may be used.
[0036]
In the case of an optical encoder unit used in the present invention, for example, as shown in FIG. 9, a light emitting element 21 and a light receiving element 22 are arranged with a code plate 24 interposed therebetween, and these elements are driven or obtained. A substrate 17 on which an electronic circuit for amplifying and shaping the received signal and adjusting the timing is formed. FIG. 9 is a partial cross-sectional configuration diagram in which parts around the encoder code plate 24 are extracted.
[0037]
As the light emitting element, a semiconductor light emitting element such as a light emitting diode (LED) or a laser diode (LD) is usually used. As the light receiving element, a semiconductor light receiving element such as a phototransistor or a photodiode is usually used. Further, when a magnetic detection method is used, it is composed of a magnetic detection element and an electronic circuit component.
[0038]
In the case of the optical type, the code plate 24 in the present invention is usually a disc-shaped slit plate having a light transmission part (so-called slit) and a light shielding part. A known incremental signal or absolute signal can be obtained by combining the light transmitting material and the light shielding portion (or a reflection type). In addition, when using the magnetic system, depending on the combination of strong and weak magnetic transmittance, a combination of coarse and dense magnetic lines of magnetic force, or a combination of a magnetic material and a non-magnetic material, a magnetic generator and a non-magnetic generator, etc. The same effect as that of the slit plate can be obtained.
[0039]
【The invention's effect】
As described above, according to the present invention, it is possible to easily position and assemble with a generally simple fitting structure with a relatively simple structure with high reproducibility compared to the conventional structure. An easy encoder and a method for attaching the encoder can be provided.
[Brief description of the drawings]
FIG. 1 is a front view showing a configuration example of an encoder of the present invention.
FIG. 2 is a side view showing a configuration example of an encoder of the present invention.
FIG. 3 is a cross-sectional view taken along the line MM ′ of FIG.
FIG. 4 is a partial cross-sectional view showing the shape of a spigot fitting part.
FIG. 5 is a partial cross-sectional view showing another shape of the spigot fitting portion.
6A and 6B are diagrams showing another configuration example of the spigot insertion portion, where FIG. 6A is a plan view and FIG. 6B is a side view.
7 is a partial plan view showing the size of a code plate in the case of an inlay insertion portion configured as shown in FIG. 6; FIG.
FIG. 8 is a diagram showing another configuration example of the spigot insertion part.
FIG. 9 is a partial cross-sectional view showing the component arrangement at the top of the code plate.
FIG. 10 is a cross-sectional view showing a configuration example of a conventional encoder.
11A and 11B are diagrams showing another configuration example of a conventional kit-type encoder, where FIG. 11A is a side view and FIG. 11B is a plan view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Encoder main body 1a Support pillar 2 Measured object 15 Screw 25 Boss 11 Rotating shaft 21 Light emitting element 22 Fixed slit plate 23 Light receiving element 24 Code plate

Claims (5)

An encoder in which an encoder body (1) is attached to a device under test (2),
The encoder mounting portion of the object to be measured (2) has an inlay fitting portion (2a) formed in a concave shape,
On the measured object mounting side of the encoder body (1), the encoder main body (1) has an inlay insertion portion (1d) that can be inserted into the inlay fitting portion and can be fitted to the measured object.
This spigot insertion part (1d) has a diameter expanding means that can be firmly fixed to the spigot fitting part (2a) by expanding at least part of the diameter formed at the lower part of the encoder body ,
The diameter expanding means cuts out a part of the spigot insertion portion (1d) having the escape hole (13) of the rotating shaft (27) of the object to be measured into a C shape, and this notch portion (12, 12a). Encoder that expands the diameter by expanding .   The encoder according to claim 1, wherein the diameter expanding means is operated by a force applied via a screw (15).   The encoder according to claim 1 or 2, wherein the diameter expanding means is operated by a force applied from a direction perpendicular to the rotation axis.   The encoder according to any one of claims 1 to 3, wherein the inlay fitting portion is formed in a reverse taper shape. An encoder mounting method in which an encoder body is mounted on a device under test,
The encoder mounting portion of the object to be measured has an inlay fitting portion formed in a concave shape, and the measuring object mounting side of the encoder body has an inlay insertion portion capable of expanding at least a part thereof. Have
This spigot insertion part is a C-shape formed in the lower part of the encoder body and having a clearance hole for the rotating shaft of the object to be measured, with a part of the spigot insertion part cut out.
An encoder mounting method in which the spigot insertion portion is inserted into the spigot fitting portion and the diameter thereof is expanded to firmly fix the spigot fitting portion to the spigot fitting portion.

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