JPS6132909B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a commutator for a flat rotor, and particularly to an improvement in the connection between the commutator and the armature winding.

Generally, this type of rotor has an armature winding 11 wound flatly in a plane perpendicular to the rotating shaft 7, and a commutator 8 press-fitted onto the rotating shaft 7, as shown in FIGS. 1 to 3. and a winding start of the winding 11,
The end of the winding is connected through a groove 6' provided in the riser part 8' of the commutator 8, and the entire winding is molded with resin 10.

The rotor is rotatably supported in a flat case 16, and rotates between magnets 14 and 15 that are arranged axially opposite each other inside the case 16.

Conventionally, in such a rotor, the two ends of the winding 11, the beginning and end of the winding, are locked together in the kerf 6' and melted and bonded by applying a high current. Since a large number of winding ends are crowded together in a narrow space around the section 8', connection work is frequent and there is a possibility of erroneous connections.

To solve this problem, a connecting conductor extending toward the opposite commutator section is connected and fixed to the riser section of each commutator section.
It is known that the beginning and end of the winding are separated and locked and connected to the tip and base of the connecting conductor.

According to this connection structure, since the windings are not crowded together in a narrow space, the work of connecting the windings to the commutator becomes easier and erroneous connections are reduced.

However, since the area of the end portion of the commutator to which the connecting conductor is fixed is very small, the connecting conductor cannot be made very thick.

In addition, the diameter of the part of the connecting conductor where the windings are connected increases by the amount of connected windings, and there is a risk of contact with adjacent conductors and short-circuiting, so make sure to make the gap between the connecting conductors sufficiently large. From this point of view, it is not possible to increase the diameter of the conductor.

As a result, the connecting conductor becomes a thin rod-like cantilever, and easily bends when a bending force is applied.

For example, if you accidentally pull the winding after it has been temporarily tightened, if you touch the connecting conductor during winding work, or if the resin injection pressure is applied directly to the winding when injecting the molding resin, or if the winding The connecting conductor is easily bent when acted upon indirectly through.

If the connecting conductor is bent, it may come into contact with other conductors and cause a short circuit, and if the bending force is large or if the bending force is applied many times, there is a risk that the connecting conductor may break off from the connection fixing part.

In particular, short circuits and breakages that occur during the injection of molding resin cannot be easily detected, leading to the production of defective products.

Furthermore, due to the rigidity of the winding temporarily attached to the tip of the connecting conductor, the tip of the connecting conductor is subject to considerable bending force, so when welding the connection point at the base, this part is When the connecting conductor melts, the connecting conductor is bent or broken due to the above-mentioned bending force caused by the winding connected to the tip.

For this reason, the connection between the winding wire and the connecting conductor must be performed using solder joints, which are difficult to work with.

SUMMARY OF THE INVENTION An object of the present invention is to provide a structure of a connecting portion in which the cross-sectional area of a connecting conductor connecting windings can be made sufficiently large, and the windings can be connected by fusion bonding.

The features of the present invention include a protrusion forming a riser part of a commutator, a first part extending on one axial side of the protrusion and forming a commutator part of the commutator, and a first part extending on the opposite axial side and forming a connecting conductor of the commutator. Each commutator piece is formed by integrally molding the three second parts forming the second part from the same conductive material, and the protrusion of each commutator piece and the opposite end of the connecting conductor part A connecting portion of the winding is formed at each of the two connecting portions, and the beginning and end of the winding are separately fused and spliced to both the connecting portions.

Next, an embodiment of a commutator for a flat rotor according to the present invention will be described with reference to FIGS. 4 to 7.

In the figure, a commutator 8 is composed of a commutator piece 1 and an insulator 2.

The original shape of the commutator is formed by drawing a copper pipe.

By drawing, several axially extending grooves are formed at equal intervals on the inner circumference of the copper pipe, and at the same time, the pipe is compressed in the axial direction to plastically deform the pipe, and a flange is formed on the outer circumference in the middle of the pipe in the axial direction. form.

After that, cuts 20 are made from both sides of the pipe to form claws 21 for preventing slippage.

The claws 21 for preventing slipping out are located on the back side of the flange portion, and one is provided between the flange portion and one end of the pipe, and one between the flange portion and the other end of the pipe.
Co-formed.

In this state, an insulator 2 made of resin is injected into the pipe and hardened. The insulator 2 also fills the groove at this time.

Note that there is a hole 22 in the center of the insulator 2 for press-fitting the rotating shaft.
is formed.

After the insulator has hardened, the outer surface of each groove is axially broached using a tool with a number of claws corresponding to each groove, and the pipe material is axially broached until the insulator 2 in the groove appears on the surface. Scrape it off. At the same time, the flange portion is cut along the groove to form independent protrusions 17, and the assembly of the protrusions forms a riser portion.

In addition, the remaining pipe material sandwiched between the insulators is removed from the commutator pieces that are electrically separated by the insulators.
becomes.

As a result, each commutator piece 1 has a boat shape integrally having a protrusion 17 on the outer periphery of the axially intermediate portion.

The cylindrical portion 3 on the right side in the drawing of the riser portion formed by the protruding portion 17 on the outer periphery of the commutator 8 forms the commutator portion 3, and the cylindrical portion 5 on the left side in the drawing forms the connection conductor portion 5. A notch 6 is formed for each commutator piece on the end surface of the connecting conductor portion 5 on the side opposite to the commutator.

Further, a hole 4 is bored in the protruding portion 17 of each commutator piece. (The hole 4 may be a cut in the radial direction.) The commutator 8 thus formed is press-fitted onto the rotating shaft 7 and fixed. At this time, the iron reinforcing member 9 is press-fitted into the shaft 7 from the side opposite to the commutator portion of the rotating shaft without contacting the vicinity of the end face of the commutator 8.

The thus formed assembly of the rotating shaft 7 and commutator 8 is fixed at the center of a winding stand (not shown), and the armature winding 11 is wound flat on the winding stand.
The starting end 12 of the winding is inserted into the hole 4 of the protrusion 17 and temporarily secured, and the ending end 13 of the winding is fitted into the notch 6 and temporarily secured.

Next, a constant high current is passed through each temporary fixing portion to melt and connect each winding end and each commutator piece at each connection portion.

In this way, the flat armature winding is arranged in a plane perpendicular to the axis between the two connecting parts of the commutator 8, and the connecting conductor part 5 on the left side from the riser part of the commutator 8 ends up in the inner space of the armature winding. The armature winding and the commutator are connected to each other while being surrounded by the winding.

Next, the rotor assembly thus assembled is integrally molded with resin 10 on a winding table.

The resin 10 flows into the gaps between the armature windings, into the internal space between the winding start 12 and the winding end 13 of the armature winding, and also flows around the entire circumference of the connecting conductor part 5 and reinforcing member 9 of the commutator 8. , fills the inner space of the armature winding 11 and its outer periphery.

When the resin hardens, the armature winding 11 is firmly fixed around the connecting conductor part 5 and the reinforcing member 9 of the commutator 8, and is finally firmly attached to the rotating shaft 7 via the connecting conductor part 5 and the reinforcing member 9 of the commutator 8. It will be fixed.

By inserting a member made of the cylindrical part 5 of the commutator 8 and the reinforcing member 9, which is more rigid than the resin, into the center of the rotor, the rigidity of the center of the rotor is increased and the centrifugal force acting on the armature winding is reduced. This prevents the resin part from being destroyed by.

In particular, in this embodiment, since the cross-sectional area of the commutator pieces on both sides of the protruding portion 17 is made substantially the same, the mechanical strength of the cylindrical portion 5 is high, and in particular, the reinforcing member 9 is extended to the inside of this connecting conductor portion. Even if the rotor does not have the required strength, the specified strength required for the rotor can be obtained.

Furthermore, in this embodiment, since a part of the commutator piece is molded together with the armature winding 11 using the resin 10, the commutator piece does not float away from the resin even when rotating at high speed. It never jumps out.

Furthermore, if configured as in this embodiment, only one wire needs to be connected to the protruding part of the commutator piece, so the radial dimension of the protruding part can be shortened, and as a result, the commutator piece can be easily operated. It can be formed using a highly efficient drawing process, and as a result, it has become possible to automate the production of commutators.

In this embodiment, the case where the insulating resin 2 reaches the inside of the connecting conductor part 5 has been described, but the insulating resin 2 is limited to only the commutator part 3, and the armature winding is not inside the connecting conductor part 5. Resin 10 to mold
It may be filled with

As explained above, according to the present invention, in order to separate the winding start and winding end of the flat rotor winding into two places and connect them to the commutator, two separate connection parts are formed in the commutator. In this process, the conductor part forming the commutator part and the conductor part forming the two separate connection parts of the commutator piece constituting the commutator, that is, the protruding part and skirt part forming the riser part are formed. Since the three conductor parts are integrally molded from the same highly conductive material, the cross-sectional area of the connecting conductor, that is, the conductor part that forms the skirt part, can be increased, and as a result, when connecting the windings, the mold resin The conductor part no longer bends or breaks during injection or winding welding, making it possible to obtain a highly reliable rotor. In addition, the windings could be connected by fusion bonding. Furthermore, by eliminating the connection points between the connection conductors and the commutator, the connection resistance in the armature winding circuit can be reduced and variations can be reduced, resulting in better electrical characteristics of the rotor. Over time, electromagnetic noise and performance deterioration disappeared.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a part of a conventional flat rotor in cross section, FIG. 2 is a side view, FIG. 3 is a perspective view of a commutator, and FIG. 4 is a flat rotor according to the present invention. 5 is a perspective view of the commutator, FIG. 6 is a half side view, and FIG. 7 is a sectional view taken along the line of FIG. 6. DESCRIPTION OF SYMBOLS 1... Commutator piece, 2... Insulator, 4... Connection hole, 6... Connection groove, 7... Rotating shaft, 8... Commutator, 10... Resin, 11... Armature winding, 1
2... end of the beginning of the roll, 13... end of the end of the roll.

Claims (1)

[Scope of Claims] 1. A flat rotor commutator having a riser part, a commutator part extending in the axial direction on one side of the riser part, and a connecting conductor part extending in the axial direction on the opposite side of the riser part. , a protrusion forming a riser part of the commutator, a first part extending axially on one side of the protrusion and forming a commutator part of the commutator, and a first part axially extending on the other side of the protrusion. a second extending portion forming a connecting conductor portion of the commutator;
A commutator piece is formed by integrally molding the three parts from the same conductive material, and a first connecting part is provided at the end of the second part opposite to the commutator part, and a first connecting part is provided at the end of the second part opposite to the commutator part, and A commutator for a flat rotor, characterized in that a second connection part is provided, and a winding start and a winding end of the winding are separately fused and spliced to both the joint parts. 2. A commutator for a flat rotor according to claim 1, wherein the cross-sectional area of the commutator pieces is substantially the same on the left and right sides of the protrusion.