JP3819735B2 - Commutator and brushed motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a brushed motor, and more particularly to a commutator assembly structure.
[0002]
[Prior art]
Conventionally, as a commutator in a brushed micromotor, a commutator holder made of a resin integrally provided with a bowl-shaped pedestal portion in a cylindrical portion (shaft mounting portion) to be fixed by press-fitting a motor shaft And three commutator pieces with metal terminals and three commutator pieces with terminals that are fixed on the outer peripheral surface of the tubular part by attaching the commutator piece on the bowl-shaped base part. And a washer as a fitting ring that is fastened simultaneously to the shape portion.
[0003]
[Problems to be solved by the invention]
However, the commutator structure described above has the following problems.
[0004]
(1) In the state where the three commutator pieces with terminals are positioned and circulated on the outer peripheral surface of the cylindrical part on the bowl-shaped pedestal part, the washers are placed on the commutator pieces of the commutator pieces with three terminals. At the time of fitting, there is an inconvenience in assembling that any of the commutator pieces are not in close contact with the cylindrical part and are difficult to fit in the washer. In particular, the commutator of the micromotor has a small size of about several millimeters, and it is necessary to tighten fitting tolerances. In addition, the assembling operation of the commutator requires skill and is an obstacle to production efficiency.
[0005]
(2) Moreover, since the assembly cost is high and a washer is required as a fitting ring, it leads to high cost of the micromotor.
[0006]
(3) In the assembly structure described above, the base portion of the terminal portion extending in the radial direction of each commutator piece overlaps the bowl-shaped pedestal portion, and this base portion is sandwiched by washers. The length in the direction must be extra longer than the effective length of the brush sliding part by the thickness of the washer, and the length of the laminated core fixed to the motor shaft compared to the motor outer dimensions. It becomes difficult to make it longer. For this reason, the motor output is sacrificed by several percent corresponding to the thickness of the washer.
[0007]
In view of the above problems, a first problem of the present invention is to provide a commutator and a brushed motor that can be assembled without the need for a fitting ring, and can be reduced in cost by reducing the number of parts. There is to do. The second problem of the present invention is to provide a commutator and a brushed motor that can reduce the length of the commutator piece by the thickness of the fitting ring that is no longer needed, and can achieve downsizing or high output. It is in.
[0008]
[Means for Solving the Problems]
In order to solve the first problem, the means of the present invention resides in that a clamp means for the commutator holder is integrally provided for each commutator piece with a terminal instead of one part of the fitting ring. .
[0009]
That is, the present invention provides a commutator holder integrally provided with a pedestal portion on the outer peripheral surface of a cylindrical portion, and a plurality of commutator pieces fixedly attached to the outer peripheral surface of the cylindrical portion on the pedestal portion. Commutator pieces with terminals of the commutator piece, the commutator piece portion on the outer peripheral surface on the surface side of the pedestal portion facing the cylindrical portion and one end portion side of the commutator piece portion in the generatrix direction. A commutator piece having a phase engagement type for positioning in an attached state, and a commutator piece with a terminal extending from the one end side and holding the pedestal portion, and extending from the clamp portion The clamp portion includes a pair of elastic flexible portions extending from both sides of the paired portion on the one end portion side, and a bridging portion between the pair of elastic flexible portions on the base portion side of the terminal portion. And has a latching portion that can be latched on the back surface of the pedestal portion .
[0010]
In such a configuration, when the mating portion on one end portion side of the commutator piece is engaged and positioned for each pair portion on the pedestal portion surface side of the commutator holder, the one end portion side is connected to the terminal portion. Since the clamp part of the part grips the pedestal part, the commutator piece is fixed in a state where the commutator piece is in contact with the outer peripheral surface of the cylindrical part. Therefore, the assembly of the commutator is completed simply by performing the assembly operation for each commutator piece with a terminal on the commutator holder, which contributes to the improvement of productivity and reduces the cost by eliminating the need for a fitting ring. Can be realized.
[0011]
According to the clamp portion of such a configuration, the pair of elastic members on the pedestal portion surface side of the commutator holder is simply engaged with the pair of the pair on one end of the commutator piece in the direction of the bus. Since the elastic flexible portion expands elastically while the latching portion corresponding to the bridging portion is slidably contacting the outer peripheral surface of the pedestal portion, the latching portion is latched on the back surface of the pedestal portion. Is secured to the base. In addition, since the elastic flexible portions are a pair of elastic flexible portions extending from both sides of the paired portion on the one end side, the elastic flexible portions are firmly fixed by increasing the spring force.
[0013]
Moreover, it is desirable that the pedestal portion is an individual pedestal portion that can be fitted between the space between the pair of elastic flexible portions. In such a case, the latching area is widened, and the pair of elastic flexible portions are arranged symmetrically about the paired portion, so that the latching force can be equalized. Furthermore, it is possible to suppress the deformation of the terminal portion in the lead wire tying step or the like.
[0014]
As each elastic flexible portion, a first valley bent portion cut and raised substantially radially from one end side, a mountain folded bent portion bent from the substantially radial direction to the back side of the pedestal portion, and a terminal portion are integrated. At least a second valley fold bent portion that is connected to each other.
[0015]
It is desirable that the outer peripheral surface of the individual pedestal portion is a tapered surface having a diameter gradually reduced in the radial direction from the back surface to the front surface. The guide action of the tapered surface makes it easy to insert the commutator piece.
[0016]
Note that the commutator piece and the terminal are not arranged at right angles but in an obtuse arrangement in advance, so that the other end of the commutator piece is elastically connected to the cylindrical portion when the insertion is completed. Since it is in a state of being drowned, the degree of adhesion is increased and the commutator piece can be prevented from floating.
[0017]
It is desirable that the phase-engaged pair is composed of an insertion hole formed in the base portion in the direction of the outer peripheral surface of the cylindrical portion, and an insertion protrusion extending from the one end side. The insertion projection piece positions and fixes one end portion of the commutator piece portion, and the pair of elastic flexible portions can easily apply a clamping force to the pedestal portion, so that robust fixation can be realized. Moreover, since the insertion protrusion can be formed by the remaining part of the pair of elastic flexible parts cut and raised, press working is facilitated.
[0018]
By using the commutator having such a structure, it is possible to obtain a miniaturized or high output brushed motor at low cost.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an exploded perspective view of a commutator according to an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIGS. 3A to 3C are longitudinal cross-sectional views illustrating how commutator pieces are assembled to a commutator holder. FIG.
[0020]
The commutator used in the small motor with brushes of this example includes a resin commutator holder 10 and three commutator pieces 20 with metal terminals.
[0021]
The commutator holder 10 includes a cylindrical portion (with an inner diameter of about 1.2 mm) 11 into which a motor shaft is press-fitted and fixed, a hook-like portion 12 integrally formed on the outer peripheral surface, and 120 of the hook-like portion. And an individual pedestal portion 13 integrally formed for each °. An insertion hole 13a having an irregular hole cross section (substantially rectangular) is formed on the surface of each individual pedestal portion 13 on the cylindrical portion 11 side. The outer peripheral surface 13b of the individual pedestal portion 13 is a tapered surface that is gradually reduced in diameter in the radial direction from the back surface to the front surface.
[0022]
On the other hand, each commutator piece 20 with a terminal includes a commutator piece portion 21 that is in contact with the outer peripheral surface of the cylindrical portion 11 on the pedestal portion 13, and a cross-sectional deformed shape (substantially rectangular) extending from one end side in the busbar direction. ) Insertion projection piece 22, a clamp portion 23 extending from one end portion thereof to elastically grip the pedestal portion 13, and a terminal portion 24 extending substantially in the radial direction therefrom.
[0023]
The clamp part 23 is bent to the back surface side of the pedestal part 13 from the _first radial folding part P ₁ , which is cut and raised in a substantially radial direction from both sides of the insertion projecting piece 22 on the one end side. A pair of elastic flexible portions 23a, 23a having a mountain fold bent portion P ₂ and a second valley fold bent portion P ₃ integrally connected to the terminal portion 24, and a pair of elastic flexible portions 23a, 23a located on the base side of the terminal portion 24 It corresponds to a bridging portion between the second valley fold bent portions P ₃ and P ₃ , and includes a latching portion 23 b that can be latched on the back surface of the pedestal portion 13. The space S between the pair of elastic flexible portions 23 a and 23 a can be fitted into the individual pedestal portion 13.
[0024]
In such commutator assembly work, only the operation of inserting the insertion protrusions 22 of the respective commutator pieces 20 into the insertion holes 13 a of the individual pedestal portion 13 of the commutator holder 10 suffices. That is, as shown in FIG. 3A, while the commutator piece 21 is in sliding contact with the outer peripheral surface of the cylindrical portion 11, the tip of the insertion protrusion 22 is fitted to the insertion hole 13a and a pair of When the commutator piece 20 is pushed so that the space S between the elastic flexible portions 23a and 23a fits into the individual pedestal portion 13, the curved edge portion of the latching portion 23b is curved on the outer peripheral surface 13b of the individual pedestal portion 13. As shown in FIG. 3 (b), the upper portion of the individual pedestal portion 13 is relatively fitted into the space S, and at the same time, the elastic flexible portions 23a and 23a are elastically expanded by the reaction. As the terminal portion 24 jumps up, the tip of the insertion protrusion 22 enters the insertion hole 13a. When the commutator piece 20 is continuously pushed in, the latching portion 23b elastically slips through the outer peripheral surface 13b of the individual pedestal portion 13 as shown in FIG. 3C, so that the elastic flexible portions 23a and 23a are elastically restored. The edges of the elastic flexible portions 23a, 23a abut against the reduced diameter portion W below the pedestal portion and are caught on the back surface 13c of the pedestal portion, and the base of the insertion protrusion piece 22 fits into the insertion hole 13a.
[0025]
When the insertion is completed, some elastic restoring force remains in the elastic flexible portions 23a and 23a, so that the clamp portion 23 elastically holds or holds the individual pedestal portion 13. The commutator piece 20 is self-fixed by the individual pedestal portion 13. On the lower side of the commutator piece 20, the insertion projection piece 22 and the latching portion 23 b are elastically sandwiched between the individual pedestal portions 13, and the retaining is achieved by the latching of the latching portion 23 b. . The individual pedestal 13 made of resin is somewhat elastically deformed by the sandwiching of the individual pedestal 13 and both surfaces slightly bulge, so that the individual pedestal 13 is also sandwiched between the elastic flexible portions 23a and 23a. Robust self-fixation is achieved.
[0026]
As described above, since the assembly of the commutator is completed without a fitting ring and with one touch, it contributes to the improvement of productivity and can realize cost reduction. For this reason, assembly automation is also possible. Further, the length of the commutator piece 21 is shortened by the thickness of the fitting ring, so that a reduction in size or an increase in output can be realized. Since the elastic flexible portions 23a and 23a can be obtained by cutting and bending from both sides of the insertion protrusion 22 and bending it, only the initial investment of the press die is required.
[0027]
The latching portion 23 b corresponds to a bridging portion between the pair of second valley fold bent portions P ₃ and P ₃ , has a large latching area, and has a pair of elastic flexible members centered on the insertion projecting piece 22. Since the parts 23a and 23a are arranged symmetrically, it is possible to equalize the latching force. Even when a force around the axis is applied when the lead wire is entangled with the terminal portion 24, the inner side surfaces of the pair of elastic flexible portions 23a, 23a abut against the side surfaces of the individual pedestal portion 13, thereby preventing rotation. Since it has a function, a deformation | transformation of the terminal part 24 can be suppressed. Moreover, since the outer peripheral surface 13c of the base part 13 is a taper surface, it becomes easy to insert the commutator piece 20 by the guide action.
[0028]
In addition, the commutator piece 21 and the terminal portion 24 are not arranged at right angles but are formed at an obtuse angle in advance so that the upper end side of the commutator piece 21 is connected to the cylindrical portion 11 in the insertion completion state. Since it is in a state of being drowned elastically, the degree of adhesion is increased and the commutator piece 21 can be effectively prevented from floating.
[0029]
【The invention's effect】
As described above, the commutator according to the present invention is characterized in that a clamp means for the commutator holder is integrally provided for each commutator piece with a terminal in order to replace the function of one part of the fitting ring. Therefore, the following effects are achieved.
[0030]
First, in order to position the commutator piece with the outer peripheral surface of the tubular portion on the surface side of the pedestal facing the tubular portion and the one end side in the generatrix direction of the commutator piece portion Since the commutator piece with a terminal extends in a radial direction from the one end side and has a clamp part for gripping the pedestal part, the commutator piece with a phase engaging type is connected to the commutator holder. Since the assembly of the commutator is completed simply by performing the assembling operation for each commutator piece with a terminal, it contributes to the improvement of productivity, and the cost can be reduced by eliminating the need for a fitting ring.
[0031]
2ndly, it only corresponds to the bridge | crosslinking part between a pair of elastic flexible parts only by engaging the pair part of the one end part side of a commutator piece part with the pair part of the base part surface side of a commutator holder in a bus-line direction. Since the elastic flexible part expands elastically while the latching part is in sliding contact with the outer peripheral surface of the pedestal part, the latching part is latched on the back surface of the pedestal part, so that the commutator piece is retained on the pedestal part Is done. In addition, since the elastic flexible portions are a pair of elastic flexible portions extending from both sides of the paired portion on the one end side, the elastic flexible portions are firmly fixed by increasing the spring force.
[0032]
Third, when the pedestal part is an individual pedestal part that can be fitted between the pair of elastic flexible parts, the latching area is widened, and the pair of elastic flexible parts is centered on the pair part. Since they are arranged symmetrically, it is possible to equalize the retaining force. Furthermore, it is possible to suppress the deformation of the terminal portion in the lead wire tying step or the like.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a commutator according to an embodiment of the present invention.
FIG. 2 is a plan view thereof.
FIGS. 3A to 3C are vertical cross-sectional views showing how the commutator pieces are assembled to the commutator holder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Resin commutator holder 11 ... Cylindrical part 12 ... Saddle-shaped part 13 ... Individual base part 13a ... Insertion hole 13b ... Outer peripheral surface 13c ... Bottom 20 ... Commutator piece 21 with metal terminals ... Commutator piece part 22 ... insertion protrusion 23 ... clamp part 23a ... flexible flexible part 23b ... holding part 24 ... terminal part P ₁ ... first valley folding part P ₂ ... mountain folding part P ₃ ... second valley folding part Part S ... Space W ... Reduced diameter part

Claims (6)

A commutator holder integrally provided with a pedestal portion on the outer peripheral surface of the cylindrical portion, and a plurality of rectifiers with terminals fixed on the pedestal portion by attaching a commutator piece to the outer peripheral surface of the cylindrical portion A commutator having a child piece,
Correlation for positioning the commutator piece with the outer peripheral surface attached to the surface side of the pedestal facing the tubular part and the one end side in the generatrix direction of the commutator piece. a pair section of the coupling type, respectively, the terminal with commutator segments has a clamp portion for gripping the base portion extending from said one end side, and a terminal portion extending from said clamp portion, The clamp portion corresponds to a pair of elastic flexible portions extending from both sides of the paired portion on the one end portion side, and a bridging portion between the pair of elastic flexible portions on the base side of the terminal portion. A commutator comprising a latching portion that can be latched on the back surface of the pedestal portion . The commutator according to claim 1, wherein the pedestal portion is an individual pedestal portion that can be fitted into a space between the pair of elastic flexible portions . 3. The elastic flexible portion according to claim 2, wherein each elastic flexible portion is a first valley fold bent portion cut and raised substantially radially from the one end side, and a mountain fold bent bent toward the back side of the pedestal portion from the substantially radial direction. site, and the commutator, characterized in that it comprises at least a second valley fold bending portion are integrally connected with the terminal portion. In claim 3, the outer peripheral surface of the individual base portions commutator, characterized in that a tapered surface gradually reduced in diameter in a radial direction toward the surface from the back surface. In any one of claims 1 to 4, pair section of the phase engagement expression, a hole Insert on the surface of the pedestal portion bored on the outer circumferential surface the generatrix direction of the tubular portion, the end portion A commutator, wherein the commutator is an insertion protrusion extending from the side. A brushed motor comprising the commutator as defined in any one of claims 1 to 5 .

Images