JPH0223083Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a brush holder used in a rotating electric machine, particularly a DC machine. A spring that is movably held inside and presses the outer end of the brush so that the inner end of the brush (the end closer to the rotor shaft) comes into contact with the commutator surface, and a power supply end to the brush. Two surfaces that hold inside a metal terminal plate that is adjacent to and abuts one end of the spring (the end farthest from the rotor shaft) and a pigtail that electrically connects the outer end of the brush. This invention relates to a brush holder that is an open box-shaped body, and is particularly designed to simplify assembly and stabilize electrical connections.

[Prior art]

The prior art and its problems will be explained with reference to FIGS. 1 and 2. FIG. 1 shows a sectional view, and FIG. 2 shows a perspective view. The brush holder is made of a metal part 21 and a resin part 22 into a box-like body with upper and lower sides open.
1 is insert molded into the resin part 22. The resin part 22 is supported by a bracket 24 of the case of the DC machine by adhesive or screwing.
A brush 23 is held inside the metal part 21 so as to be slidable in the vertical direction (direction perpendicular to the surface of the commutator 31 integral with the rotor shaft 30). 2
5 is the outer periphery of the case of the DC machine. Reference numeral 26 denotes a spring that presses the outer end of the brush 23. Its upper end is in contact with the lower surface of a metal terminal plate 27 that serves as the power supply end to the brush 23, and its lower end is pressed against the outer end of the brush 23, i.e. It is in contact with the upper end surface. A pigtail 28 electrically connects the brush 23 and the terminal plate 27. As shown in the perspective view of FIG. 2, the brush 23 is equipped with a spring 26, a pigtail 28, and a terminal plate 27 so that the brush 23 can be attached to and removed from the brush holder from outside the case after the motor is assembled.
is attached in advance, and is inserted into the metal part 21 of the brush holder.Then, by turning the top surface of the terminal plate 27 with a screwdriver and moving the cap 32, which has a thread machined on the outer periphery, in a straight line, It is designed to be pressed by the lower end surface of 32. Reference numeral 29 denotes a lead wire for power supply, one end of which is connected to a terminal portion 21' provided on the metal portion 21 of the brush holder, and the other end connected to an external power source (not shown). Electricity is supplied from the lead wire 29 through the route of terminal portion 21'→metal portion 21→terminal plate 27→pigtail 28→brush 23→commutator 31.

However, the conventional structure described above has the following problems. That is, the brush holder includes a metal part 21 and a resin part 22, and this metal part 2
It is constructed by attaching the terminal section 21' for energizing to the terminal section 1, and then the terminal board 27 of this brush section is held down by the cap 32 after inserting the brush section, so the number of parts is large and the number of man-hours required for assembly is reduced. Moreover, as mentioned above, electricity is supplied from the lead wire 29 through the terminal plate 27, and the connection between the metal part 21 and the terminal plate 27 is provided by a screw on the outer periphery of the cap 32. Since the terminal plate 27 is pressed down, it is difficult to keep this pressing force constant at all times, and there is a problem in that the contact is likely to become unstable, especially during repairs such as replacing the brush.

[Purpose of invention]

An object of the present invention is to provide a brush holder for a DC machine having a structure that solves the above-mentioned problems with the conventional structure, simplifies assembly, and ensures reliable contact.

[Summary of the idea]

The features of this invention are, in order to achieve the above objectives,
The box-shaped brush holder is made of a synthetic resin molded product, and a U-shaped terminal plate is made of an elastic metal plate to sandwich the two opposing sides of the box-shaped body. Each claw is provided so as to protrude outward,
An engagement hole was formed on the side of the U-shaped terminal plate to engage with the hook-shaped claw and enable the terminal plate to be locked to the brush holder simply by inserting the terminal plate, and provided in the bracket. The structure is such that an elastic plate made of an insulator whose both ends are supported by a groove presses the terminal plate via a lead wire disposed on the surface of the terminal plate.

[Example of idea]

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5. Figure 3 shows a sectional view, Figures 4 and 5
Each figure shows a perspective view of the main parts. Figures 3 to 5
In the figure, reference numeral 1 denotes a brush holder, which is molded into a box-like body from synthetic resin. If the bracket 4 of the DC machine case is made of synthetic resin, the bracket 4 and brush holder 1 may be integrally molded. .
In any case, the brush holder 1 is integrally attached to the bracket 4 at a side that is not visible in the drawings. 3 is a brush, one end of which is in contact with the surface of the commutator 31, one end of a pigtail 8 is connected to the other end, and the other end of this pigtail 8 is connected to the lower surface of the terminal plate 7. ing. Further, a spring 6 is disposed between the upper end surface of the brush 3 and the lower surface of the terminal plate 7 to connect the brush 3 to the commutator 3.
It is pressed in direction 1. Hook-shaped claws 11 and 12 are provided on two opposing sides of the brush holder 1, respectively.
is provided so as to protrude outward. The terminal plate 7 is made of an elastic metal plate so as to sandwich the two opposing sides of the brush holder 1 in a U-shape, and engages with the two hook-shaped claws 11 and 12 to insert the terminal plate 7. Engagement holes 71 and 72 are provided for locking the terminal plate to the brush holder 1 with just an operation. Reference numeral 9 denotes a power supply lead wire, the end of which is connected to the terminal board 7 on the upper surface of the terminal board 7. Reference numeral 20 denotes an elastic plate made of an insulating material, which can be attached to the bracket 4 by inserting its both ends into grooves previously provided in the bracket 4.
The upper surface of the terminal plate 7 is pressed through the lead wire 9. Note that 13 is a notch provided at the upper end of the brush holder 1. When removing the terminal plate 7 from the brush holder 1, insert the tip of a screwdriver into the notch 13 and turn the driver to remove the terminal plate. 7 can be removed.

In the above case, the hook-shaped claws 11 and 12 provided protruding from both side surfaces of the brush holder 1 have their lower portions perpendicular to the side surfaces, as shown in the sectional view in FIG. 3 and the perspective view in FIG. By making the terminal board 7 into a rising shape with a gentle slope at the top.
By simply inserting the terminal plate 7 along the side surface of the brush holder 1, the terminal plate 7 can be assembled into the brush holder 1 in a manner that prevents it from coming off. The terminal plate 7 having the engagement holes 71 and 72 that engage with the hook-shaped claws 11 and 12 is manufactured by forming a single elastic metal plate into a rectangular shape, as shown in the perspective view of FIG. When cutting, a U-shaped parting line extending from the top surface of the board to the bottom surface of the board is cut at both ends at the same time, and the engagement holes 71,
The terminal plate 7 can be provided with 72.

[Effect of idea]

The brush holder of the present invention having the above structure produces the following effects. The terminal plate 7, which serves as the power feeding end to the brush, and the lead wire 9 are directly electrically connected on the surface of the terminal plate 7, and the portion of the lead wire 9 near the connection point is the terminal. Since the structure is sandwiched between the plate 7 and the elastic plate 20, a more reliable electrical connection can be achieved than in the case of the conventional structure, and the cause of unstable contact as in the conventional structure is eliminated. By using the elastic plate 20 as an elastic plate made of an insulator that also serves as insulation from the outside and pressing the terminal plate 7 via the lead wire 9, the tolerance for dimensional errors between each component is widened. For example, even if the top surface of the terminal plate 7 is slightly distorted,
Alternatively, even if there are variations in the U-shaped bending width of the terminal plate 7, the terminal plate 7 can be securely fixed to the upper end of the brush holder 1, and the advantages are that each part can be manufactured easily. There is. moreover,
Since the terminal board 7 can be assembled into the brush holder 1 simply by inserting the terminal board 7, the number of assembly steps can be significantly reduced compared to the conventional structure, resulting in an inexpensive product. be able to provide it.

[Brief explanation of the drawing]

Fig. 1 is a sectional view for explaining a conventional example, Fig. 2 is a perspective view of the brush portion thereof, Fig. 3 is a sectional view showing an embodiment of the present invention, Fig. 4 is a perspective view of the brush portion, FIG. 5 is a perspective view of the box-like body of the brush holder. Explanation of symbols, 1... Brush holder, 3, 23...
...Brush, 4,24...Bracket, 6,26...
...Spring, 7,27...Terminal board, 8,28...Pigtail, 9,29...Lead wire, 11,12...
Hook-shaped claw, 13...notch, 20...elastic plate, 2
1... Metal part of the brush holder, 22... Resin part of the brush holder, 25... Outer circumference of the case, 30...
Rotor shaft, 31... Commutator, 71, 72... Engagement hole.

Claims (1)

[Scope of utility model registration request] A spring supported by a bracket of a case of the DC machine to slidably hold the brush inside and press the other end of the brush so that one end of the brush comes into contact with the commutator surface, and the other end of the brush. A brush holder consisting of a box-shaped body with two open sides holding therein a pigtail that serves as a power supply end to the brush and electrically connects a metal terminal plate that abuts one end of the spring. A box-like body made of aluminum, a U-shaped terminal plate sandwiched between the two opposing sides of the box-like body is made of an elastic metal plate, and hook-shaped claws are protruded outward from each of the two sides. an engaging hole is formed on the side of the U-shaped terminal plate that engages with the hook-shaped claw and enables the terminal plate to be locked to the brush holder simply by inserting the terminal plate;
A DC machine characterized in that the terminal plate is pressed by an elastic plate made of an insulating material whose both ends are supported by a groove provided in the bracket through a lead wire arranged on the surface of the terminal plate. brush holder.