JPH07336962A - Manufacturing method for commutator groove - Google Patents

Abstract

PURPOSE:To reduce an error to half as compared with a conventional one in a step for manufacturing a commutator groove, by adding a mean value of differences between a theoretical value and a segment groove pitch measured by turning a commutator at each groove center when a base manufacturing reference point is measured. CONSTITUTION:A central point P0 in one segment groove is used as a temporary reference point of cutting. An adjacent central point P1 is measured by turning a commutator and a length from the reference point P0 to the central point P1 is calculated. A difference DELTAP1 between the length anal a theoretical value (360 deg.,/n; n is the number of segments) is calculated. Then, central point P1, P2..., Pn in segment grooves are each measured by turning the commutator one revolution. After each length from the temporary reference point P0 is sought, differences DELTAP1, DELTAP2..., DELTAPn from each theoretical value are calculated. A mean value is calculated by dividing the total of differences by the number (n) of commutator segments. A real cutting reference value is obtained by adding the mean value to the temporary reference value P0.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a groove processing method for a commutator mounted on an armature of an electric motor.

[0002]

2. Description of the Related Art The following method is used to manufacture a high speed rotating commutator. That is, a commutator segment and a mica plate are alternately sandwiched to form a segment ring, which is resin-molded to form a segment ring, and JP-B-58-5515.
This is a method of bending a strip-shaped conductive wire plate to form an annular ring and performing cold forging to form a segment ring at a time as shown in Japanese Patent Publication No. In the former method in which commutator segments and mica plates are alternately combined, a commutator segment width processing error and a mica thickness error occur. In particular, the mica plate undergoes a large dimensional change due to compression, and when the commutator is manufactured, the segment groove spacing changes greatly. Further, in the latter method in which the segment ring is formed at a time by cold forging, the degree of cold forging die production (die machining error) causes an error in the segment groove spacing. However, this error is relatively small. Further, even if the segment ring is created by either of the above methods, when the segment ring is molded with the molding resin, the commutator segment interval does not match because the center of the segment ring and the outer diameter machining center position of the commutator do not match. Isometric. Due to the above reasons, the commutator segment spacing varies, so
It was necessary to process the commutator segment or the segment groove.

A conventional method of forming a groove for a commutator will be described in Japanese Patent Laid-Open No. 63-240348. In FIG.
A commutator 1 is a commutator segment 2 made of a conductor.
And a segment groove 3 made of an insulator (mica plate) that insulates the commutator segment 2 from each other. Reference numeral 4 denotes an optical sensor for detecting the position of the segment groove 3 by projecting light 9 on the side surface of the commutator 1 and detecting the reflected light to detect the segment groove 3. Reference numeral 5 denotes a cutter for processing the segment groove 3. Reference numeral 6 is a motor for rotating the commutator 1 by a predetermined angle, which is rotationally driven by the controller 8. 7
Is a rotary encoder connected to the motor 6.
The optical sensor 4 and the cutter 5 are arranged at a constant phase angle.

Next, the above operation will be described. The commutator 1 is rotated by a predetermined angle by the motor 6, and at the same time, the rotary encoder 7 is associated with the signal from the optical sensor 4.
Read the output pulse signal of. That is, since the commutator segment 2 and the segment groove 3 have different light reflectivities, the signal from the optical sensor 4 draws a high and low wave as shown by the line 10 in FIG. The change point from the high level to the low level or from the low level to the high level indicates the apparent boundary between the commutator segment 2 and the segment groove 3, and the output pulse signal of the rotary encoder 7 can be read in association with this change point. In this case, it means that the position data of the above boundary has been taken in. Here, for example, when the above work is performed at an angle corresponding to five commutator segments (range from the broken line S to the broken line E in FIG. 11), at least the position data indicating the start and end of the segment groove 3 is obtained. You can get about individual pieces. Subsequently, the center position of each segment groove is calculated from the position data of the beginning and the end of the segment groove 3. Further, the center-to-center distance (arrangement pitch) between adjacent segment grooves is obtained from the center position of each segment groove 3. The array pitch values thus obtained (X ₁ , X ₂ , X in FIG. 11)
₍₃ , X ₄ ) are individually compared with the reference value, and if three consecutive values are within the allowable tolerance, the apparent boundaries of the commutator segment 2 and the segment groove 3 deviate from the true boundary during this period. It is determined that the center point of the array pitch in the center is not the center of the commutator segment 2 included therein,
This point is set as the cutting reference point. Since the center of the commutator segment 2 closest to the cutter 5 exists at a point distant from the cutting reference point by a predetermined angle, the motor 6 adjusts the angle of the commutator 1 so that this point faces the cutter 5, and the cutting is started. To do. When processing of one commutator segment 2 is completed, indexing rotation is performed, and then processing of the next commutator segment 2 is started. In this way, the work is completed by rotating the commutator 1 once. The same applies when the measurement target is replaced with the arrangement pitch of the commutator segments. Further, in the above, the arrangement pitches of the segment grooves 3 or the commutator segments 2 are checked for three, but it is also possible to check whether or not at least two arrangement pitches are continuously within the allowable tolerance. .

[0005]

As described above, the conventional commutator groove processing method obtains the center-to-center distance (arrangement pitch) of the segment grooves (or commutator segments) and determines the reference value (3).
60 ° / n), and check whether at least two of them are continuously within the tolerance, and if it is within the tolerance, the midpoint of the commutator segment or the midpoint of the segment groove is used as the cutting reference point. As described above, the groove processing is performed while the index rotation is performed at an equal angle.

Here, as shown in FIG. 2, the segment groove 3 is formed.
The interval (X ₁ , X ₂ , X ₃ , X ₄ ...) Is 360 ° / n (n is the number of commutator segments 2) and the reference value is, for example, the error is ΔP ₁ , ΔP ₂ ,. When the commutator 1 is rotated once, a curve as shown in FIG. 3 is drawn. In this case, if at least two or more commutator segments are measured and are within the allowable tolerance as in the above-mentioned conventional method, if grooving is performed as a cutting reference point, for example, point P _{A in} FIG. 3 is the cutting reference point. If the grooving is performed with a width of the reference value (360 ° / n) from here, the maximum error is the distance │ΔP _A │ + │ΔP _B │ (where P _A is Only the error ΔP _A , the error ΔP _B at the point P _B occurs, and in an extreme case, the commutator segment at a position other than the segment groove or the segment groove at a position other than the commutator segment may be cut.

The present invention has been made to solve the above problems, and an object of the present invention is to improve the manufacturing quality of a commutator by suppressing the error in machining the groove of the commutator to half that of the conventional method. And

[0008]

A commutator groove machining method according to a first aspect of the present invention is as follows: (1) The center position P ₀ of an arbitrary segment groove is indexed, and this position P ₀ is a temporary cutting reference position. And (2) the distance between the position P ₀ and the center positions P ₁ , P ₂ , ..., P _n of the segment grooves that are successively adjacent to each other is calculated, and the differences ΔP ₁ and ΔP ₂ from the theoretical values are calculated. ..., the process of obtaining ΔP _n , and (3) the sum of the differences between the theoretical values (ΔP ₁ + ΔP ₂ + ...
+ ΔP _n ) and dividing by the number n of commutator segments to obtain an average value Px = 1 / n (ΔP ₁ + ΔP ₂ + ... + ΔP _n ), and (4) the above average value at the temporary cutting reference point P _0. P
x, and a cutting reference position Py = P ₀ + Px is set, and (5) a segment groove is processed with the position Py as a processing reference position.

According to a method of machining a groove of a commutator of claim 2, (1) a step of indexing a center position Q ₀ of an arbitrary commutator segment and setting this position Q ₀ as a temporary cutting reference position, (2) The difference between the position Q ₀ and the central position Q ₁ , Q ₂ , ..., Q _n of the adjacent commutator segments is calculated, and the difference Δ from the theoretical value is calculated.
, Step of obtaining Q ₁ , ΔQ ₂ , ..., ΔQ _n , and (3) obtaining the sum total of the difference between the above theoretical value (ΔQ ₁ + ΔQ ₂ + ... + ΔQ _n ) and dividing by the number n of commutator segments to obtain the average value Qx. = 1 / n (ΔQ
₁ + ΔQ ₂ + ... + ΔQ _n ), (4) adding the above-mentioned average value Qx to the provisional cutting reference point Q ₀ and setting the cutting reference position Qy = Q ₀ + Qx, and (5) position Qy Is used as a processing reference position to process a groove (for example, a connection groove) of the commutator segment.

According to a third aspect of the present invention, the hook groove of the commutator is machined sequentially by using the point Py obtained by the method of the first aspect as a machining reference position.

[0011]

In the invention of claim 1, the center position P ₀ of any segment groove is obtained, the commutator is rotated once, and the difference between the interval between adjacent segment grooves and the theoretical value (360 ° / n) is calculated for all segments. Since the groove is obtained and this average value is added to the first indexing position P ₀ as the processing reference position, the groove cutting error can be reduced to about half of the conventional value.

In the second aspect of the invention, the center position Q ₀ of any commutator segment is determined, the commutator is rotated once, and the interval between adjacent segments and the theoretical value (360 ° / n).
Is calculated for all segments, and this average value is added to the first indexing position Q ₀ as the machining reference position.
The grooving error can be reduced to about half of the conventional one.

According to the third aspect of the invention, the error in machining the hook groove of the commutator can be reduced to about half that in the conventional case.

[0014]

【Example】

Example 1. FIG. 1 shows a flow chart for executing the groove machining method of the present embodiment, FIG. 2 is a diagram showing the difference between the segment groove intervals and the theoretical value, and FIG. 3 shows the segment groove intervals when the commutator is rotated once. It is an error diagram. As an example of the apparatus for executing the method of the present invention, the same apparatus as that shown in FIG. 8 described in the prior art may be used, and the description thereof is omitted.

This embodiment will be described with reference to the flow chart of FIG. 1. First, in S100, the commutator 1 is rotationally driven by the motor 6, the center position P ₀ of the arbitrary segment groove 3 is indexed, and the center position P is calculated. Set ₀ as a temporary cutting reference point. Next, in S200, the commutator 1 is further rotated to determine the center position P ₁ of the adjacent segment groove 3, the distance (angle) from the reference point P ₀ is calculated, and the distance (angle) and the theoretical value ( 360 ° / n; n is the number of segments) and the difference ΔP ₁ is calculated. In this way, the commutator 1
Rotate and rotate the center position of each segment groove P ₁ , P ₂ ,
, P _n are calculated, the distance from the reference point P ₀ is calculated, and the differences ΔP ₁ , ΔP ₂ , ..., ΔP _n from the theoretical values are obtained.
Next, in S300, the sum of the difference from the theoretical value (ΔP ₁ +
ΔP ₂ + ... + ΔP _n ) is calculated, divided by the number of commutator segments n, and the average value Px = 1 / n (ΔP ₁ + ΔP ₂ + ... + Δ
P _n ). Then, in S400, the process returns to the first segment groove 3 and the average value Px is added to the provisional cutting reference point P ₀ , and a new cutting reference point Py = P ₀ +
Set Px. Finally, in S500, the commutator is rotated by the theoretical value (360 ° / n) with the point Py as the processing reference position, and the segment groove 3 is processed.

The above groove machining method will be further described with reference to the error curve in FIG. 3. A new cutting standard in which the average value Px of the sums of the differences from the theoretical value (360 ° / n) is added to the first cutting reference point P _0. The point Py means the horizontal axis Py (dotted line) in FIG. 3, and is the position where the sum of the differences from the theoretical value for one revolution of the commutator is zero. This means that the machining reference point Py comes to the middle position of the error of the groove interval, and when the segment groove is cut at the theoretical value (360 ° / n) interval from the reference point Py, the error is almost the same as before. It is half the maximum error of. Therefore, when the segment groove 3 is cut as in the conventional case, the probability of cutting the commutator segment 2 is reduced to half, and the quality of the groove processing of the commutator 1 can be significantly improved.

In the above embodiment, the error curve of the interval between the segment grooves when the commutator is rotated once is explained by the sine curve as shown in FIG. 3, but any error curve, for example, FIG.
The same can be applied to the error curve of.

Example 2. The groove processing method according to the above-described first embodiment can be applied when processing the connection groove that connects the commutator and the armature coil. FIG. 7A shows a front view of a commutator having a connection groove, and FIG. 7B shows a side view thereof. In the figure,
Reference numeral 11 indicates a riser section. This riser portion 11 has a connection groove 1
2 and insert the end of the armature coil into the connection groove 12 to connect to the commutator segment 2. Reference numeral 13 represents a mold resin. The operation of the second embodiment will be described with reference to FIGS. FIG. 5 is a flow chart for executing the groove machining method according to the second embodiment, and FIG. 6 is a diagram showing the difference between the segment interval and the theoretical value. First, the center position Q ₀ of an arbitrary commutator segment 2 is indexed, and the position Q ₀ is set as a temporary cutting reference position. Next, the center position Q ₁ of the adjacent commutator segment 2 is indexed, the distance from the reference point Q ₀ is calculated, and the difference ΔQ between this distance and the theoretical value (360 ° / n; n is the number of segments). Ask for ₁ . In this way, the commutator is rotated _once and the center position Q ₁ ,
Q _2, ..., indexing the Q _n, calculates the distance between the reference point Q _0, the difference Delta] Q ₁ from the theoretical value, respectively, ΔQ _2, ..., seek Delta] Q _n. Furthermore, the sum of the difference from the above theoretical value (ΔQ ₁ + ΔQ ₂
+ ... + ΔQ _n ) is calculated and divided by the number of commutator segments n, and the average value Qx = 1 / n (ΔQ ₁ + ΔQ ₂ + ... + ΔQ _n )
Ask for. Then, returning to the first commutator segment 2, the average value Qx is added to the provisional cutting reference point Q ₀ to set a new cutting reference point Qy = Q ₀ + Qx. Finally, the theoretical value (3
The commutator is rotated by 60 ° / n) to process the connection groove.

Example 3. The commutator shown in FIG. 7 is mainly used for large current. The commutator shown in FIG. 8 is for a small current and is a simplified version of the riser portion 11 shown in FIG. 7 and is called a hook type. The present embodiment provides a method for processing the hook groove of the hook type commutator. In FIG. 8, 14 is a commutator segment, and a hook 15 is formed at the rear end thereof, and an armature coil 17 is hooked and wound on this hook 15. 1
6 is a hook groove formed between the hooks 15, and 19 is a mold resin. Next, the hook groove processing of this embodiment will be described with reference to FIG. First, as shown in FIGS. 9A and 9B, a commutator 200 having a flange portion 110 integrated with the commutator segment 14 and the segment groove 3 at the rear end thereof is prepared, and described in the first embodiment. The processing reference point Py in the segment groove 3 is obtained by the same method as described above. Then, as shown in FIG. 9C, the point Py is used as a processing reference position and rotated by a theoretical value (360 ° / n; n is the number of commutator segments) from this point, and the width w is increased by the wide cutter 50.
The hook groove 16 of is processed sequentially. Finally, when the processing of all the hook grooves 16 is completed, the remaining flange piece 110a is bent forward as shown in FIG.
To complete the hook type commutator shown in FIG.

[0020]

As described above, according to the first aspect of the invention, the center position P ₀ of an arbitrary segment groove is obtained, and the difference between the segment groove interval and the theoretical value (360 ° / n) is calculated by the commutator. All the segment grooves are obtained, and the average value is added to the first indexing position P ₀ to set the machining reference position, and the segment groove machining is performed by rotating theoretical values, so that the commutator groove cutting error is reduced to about the conventional value. It can be reduced to half and the quality can be greatly improved.

According to the second aspect of the invention, the center position Q ₀ of any commutator segment is determined, the difference between the segment interval and the theoretical value (360 ° / n) is determined for all segments of the commutator, and this average is calculated. The value is added to the first indexed position Q ₀ as the machining reference position, and the theoretical value is rotated to machine the connection groove, etc., so that the groove cutting error can be reduced to about half that of the conventional method. Can be improved.

According to the third aspect of the invention, the error in machining the hook groove of the commutator can be reduced to about half of the conventional one, and the quality can be improved.

[Brief description of drawings]

FIG. 1 is a flowchart of a commutator groove processing method according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a theoretical value of a segment groove interval and its difference in Example 1.

FIG. 3 is an error diagram of segment groove intervals when the commutator of Example 1 is rotated once.

FIG. 4 is an error diagram of the segment groove spacing when the commutator of the first embodiment is also rotated once.

FIG. 5 is a flowchart of a commutator groove processing method according to a second embodiment.

FIG. 6 is an explanatory diagram showing a theoretical value of a commutator segment interval and its difference according to the second embodiment.

7A and 7B are a front view and a side view showing a commutator having a connection groove according to a second embodiment.

FIG. 8 is a perspective view showing a hook type commutator of a third embodiment.

9A and 9B are a partial front view and a side view showing a groove processing step of a hook type commutator according to a third embodiment.

FIG. 10 is a schematic diagram showing an example of an apparatus for executing the method of the present invention.

FIG. 11 is a diagram for explaining a conventional operation.

[Explanation of symbols]

 1 Commutator 2 Commutator segment 3 Segment groove 4 Optical sensor 5 Cutter 6 Motor 8 Controller 9 Laser light 11 Riser part 12 Connection groove 14 Commutator segment 15 Hook 16 Hook groove

Claims (3)

[Claims] 1. A method of processing a commutator segment made of a conductor and a commutator segment groove made of an insulator that insulates the commutator segment from each other, comprising: (1) a center position P _{0 of} an arbitrary segment groove; And the position P ₀ is used as a temporary cutting reference position, and (2) the position P ₀ and the center position P ₁ of the segment grooves that are successively adjacent to _{each other} .
The distance from P ₂ , ..., P _n is calculated, and the difference from the theoretical value ΔP ₁ ,
[Delta] P _2, ..., a step of determining the [Delta] P _n, (3) the calculated sum of the difference between the theoretical value _{(ΔP 1 + ΔP 2 + ...} + ΔP n), divided by the number of commutator segments n, the average value Px = 1 / n (ΔP ₁ +
ΔP ₂ + ... + ΔP _n ), (4) adding the average value Px to the temporary cutting reference point P ₀ and setting the cutting reference position Py = P ₀ + Px, and (5) the position Py. And a step of machining the segment groove with the machining reference position as a machining reference position. 2. A method of processing a commutator segment made of a conductor and a groove of a commutator made of an insulator that insulates the commutator segment from each other, comprising: (1) a center position Q _{0 of} an arbitrary commutator segment. And the position Q ₀ is used as a temporary cutting reference position, and (2) the position Q ₀ ,
Center positions Q ₁ , Q ₂ , ..., Q of adjacent commutator segments
The interval from _n is calculated, and the difference from the theoretical value ΔQ ₁ , ΔQ ₂ , ...,
The sum of the difference between the step of obtaining ΔQ _n and (3) the theoretical value (Δ
Q ₁ + ΔQ ₂ + ... + ΔQ _n ) is calculated, divided by the number of commutator segments n, and the average value Qx = 1 / n (ΔQ ₁ + ΔQ ₂ + ... + Δ
A step of determining the Q _n), (4) cutting the reference point Q ₀ of the temporary
To the cutting reference position Qy =
A commutator grooving method comprising: a step of setting Q ₀ + Qx; and (5) grooving a commutator segment with the position Qy as a machining reference position. 3. A commutator groove machining method, wherein the commutator hook groove is machined using the point Py obtained by the method of claim 1 as a machining reference position.