JP3004008U - DC motor with terminal bolt - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a DC motor with terminal bolts that can prevent application of tightening pressure to a resin brush plate without using a metal collar. [Structure] The positive terminal bolt 16 includes a bottomed cylindrical insulating collar 19 in which an insulating spacer portion 19a is fitted in a bolt through hole 18 of a metal rear cover 5, a rear cover 5, and a resin brush plate 15. And the nut 22 are collectively tightened. The negative terminal bolt 17 is attached to the rear cover 5
The rear cover 5 and the brush plate 15 are collectively tightened with the nut 26 in a state of being body-grounded. The positive terminal bolt 16 is provided with a large diameter portion 16b at a portion from the bolt head 16a to the inner surface of the bottom portion 19c of the insulating collar 19. The negative terminal bolt 17 is provided with a large diameter portion 17b at a portion from the bolt head 17a to the rear cover contact surface of the brush plate 15.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC motor with terminal bolts, which is provided with terminal bolts as electrode terminals penetrating a metal rear cover.

[0002]

[Prior art]

 3 and 4A and 4B show the structure of a conventional DC motor with terminal bolts of this type. The DC motor with terminal bolts is provided with a bottomed tubular iron yoke 1, and a magnet 2 is attached to the inner periphery thereof to form a stator 3. A bearing support cylinder portion 1b is provided at the center of the bottom portion 1a of the yoke 1, and the bearing 4 is supported by the bearing support cylinder portion 1b. An opening portion of the bottom yoke 1 opposite to the bottom portion 1a is closed by an iron rear cover 5. A bottomed bearing support cylinder portion 5a is provided in the center of the rear cover 5, and a bearing 6 is supported by the bearing support cylinder portion 5a.

A rotor 7 is incorporated in the center of the stator 3 along the axis thereof. The rotor 7 includes a rotary shaft 8 rotatably supported by bearings 4 and 6, a rotor core 9 attached to the rotary shaft 8 corresponding to the magnet 2, and a rotor core 9 wound around the rotor core 9. The main winding 10 is formed.

A commutator 11 is attached to the outer circumference of the rotary shaft 8 between the rotor core 9 and the bearing 6.

A brush plate 15 made of resin is superposed on the inner surface of the rear cover 5, and the overlapping portion of the rear cover 5 and the brush plate 15 is penetrated to form a positive terminal bolt 16 and a negative terminal bolt 17, respectively. It is provided.

As shown in FIG. 4B, the positive terminal bolt 16 is fitted with an insulating spacer portion 19 a in the bolt through hole 18 of the rear cover 5 to insulate the positive terminal bolt 16 from the rear cover 5. A bottomed cylindrical insulating collar 19, a rear cover 5, and a brush plate 15 are collectively tightened with a nut 22 via a plain washer 20 and a spring washer 21. The insulating collar 19 has a bottomed tubular shape having a tubular portion 19b and a bottom portion 19c provided at one end thereof, surrounds a bolt through hole 19d at the center of the bottom portion 19c, and extends outward to the bottom portion 19c. A ring-shaped insulating spacer portion 19a is provided so as to project from the inside. The insulating collar 19 has an insulating spacer portion 19a fitted in the bolt through hole 18 of the rear cover 5 with the outer surface of the bottom portion 19c thereof being in contact with the rear cover 15. A metal collar 23 is fitted on the positive terminal bolt 16 from the end of the bolt head 16 a to the surface of the bottom 19 c of the insulating collar 19.

As shown in FIG. 4A, the negative terminal bolt 17 is provided by collectively tightening the rear cover 5 and the brush plate 15 with the nut 26 via the plain washer 24 and the spring washer 25. There is. A metal color 27 is fitted to the negative terminal bolt 17 from the end of the bolt head 17a to the rear cover contact surface of the brush plate 15.

As the metal collars 23 and 27, a metal pipe or a metal plate rolled into a tubular shape is used.

Although not shown, the brush is attached to the brush plate 15 at a position 90 ° apart in the circumferential direction of the brush plate 15 from the position where the positive terminal bolt 16 and the negative terminal bolt 17 are provided. And is in contact with the commutator 11.

As described above, in the conventional DC motor, when the positive terminal bolt 16 and the negative terminal bolt 17 are used as the electrode terminals and the rear cover 5 is penetrated and pulled out to the outside, the resin brush plate 15 is It is fixed by tightening the terminal bolts 16 and 17 and the nuts 22 and 26, but there is a risk that the brush plate 15 will contract due to temperature or the passage of time, causing the nuts 22 and 26 to loosen and disconnecting the connection terminals. Therefore, it is necessary to interpose the metal collars 23 and 27 so that the tightening pressure from the nut 22 is not applied to the resin-made insulating collar 19 and the brush plate 15 on the positive terminal bolt 16 side. On the bolt 17 side, it is necessary to prevent the tightening pressure from the nut 26 from being applied to the resin brush plate 15.

The metal collar 23 is assembled by inserting it into the brush plate 15 or the insulating collar 19 at the time of resin molding so as to be integrated with one of them beforehand, or by inserting it into the positive terminal bolt 16 at the time of assembly.

Similarly, the metal collar 27 is assembled by inserting it during resin molding of the brush plate 15 and integrating it in advance, or by inserting it into the negative terminal bolt 17 during assembly.

[0013]

[Problems to be solved by the device]

 However, when the metal collars 23 and 27 are used in this way, when inserting in advance, it takes a lot of time to set these metal collars 23 and 27 in the molding die, and when the metal collars 23 and 27 are not inserted in terms of molding conditions. There is a problem that molding is more complicated than that.

On the other hand, when inserting into the terminal bolts 16 and 17 at the time of assembly, there is a problem that the number of steps is naturally increased.

An object of the present invention is to provide a direct current electric motor with a terminal bolt that can prevent application of tightening pressure to a resin brush plate or an insulating collar without using a metal collar.

[0016]

[Means for Solving the Problems]

 According to the present invention, a positive terminal bolt and a negative terminal bolt are respectively provided by penetrating a portion where a resin brush plate is superposed on a metal rear cover that closes an opening of a yoke. Is a bottomed cylindrical insulating collar that insulates the positive terminal bolt from the rear cover by fitting an insulating spacer portion into the bolt through hole of the rear cover, the rear cover and the brush plate together with a nut. The DC motor with terminal bolts, which is provided by tightening the rear cover and the brush plate together with nuts in a state where the negative terminal bolts are body-grounded to the rear cover, is targeted for improvement. .

In the present invention, the positive terminal bolt is provided with a large diameter portion from the bolt head to the inner surface of the bottom of the insulating collar, and the negative terminal bolt is provided with the brush head from the bolt head. It is characterized in that a large-diameter portion is provided in a portion of the plate reaching the rear cover contact surface.

In this case, the positive terminal bolt is located between the bottom of the insulating collar and the nut, and the plain washer and the spring washer are fitted to the positive terminal bolt, and the rear cover and the nut are attached to the negative terminal bolt. The plain washer and the spring washer can be fitted to each other by arranging the plain washer and the spring washer.

[0019]

[Action]

 In this way, for the positive terminal bolt, a large diameter part is provided from the bolt head to the inner surface of the bottom of the insulating collar, and for the negative terminal bolt, the bolt head contacts the brush plate rear cover. If a large-diameter portion is provided on the surface, it is possible to prevent the tightening pressure from being applied to the resin brush plate and the insulating collar without using the metal collar.

As described above, when the terminal bolt is provided with the large-diameter portion, the metal collar is not necessary, and therefore the problems at the time of molding and the problems at the time of assembly can be solved.

Further, the positive terminal bolt is located between the bottom of the insulating collar and the nut, and the plane washer and the spring washer are fitted to the positive terminal bolt, and the negative terminal bolt is located between the rear cover and the nut. By fitting the plain washer and spring washer together, the nut tightening can be stabilized.

[0022]

【Example】

 1 and 2A and 2B show an embodiment of a DC motor with terminal bolts according to the present invention. The parts corresponding to those in FIGS. 3 and 4A and 4B described above are denoted by the same reference numerals.

In the present embodiment, the positive terminal bolt 16 is provided with a large diameter portion 16b in a portion from the bolt head 16a to the inner surface of the bottom portion 19c of the insulating color 19, and the negative terminal bolt 17 is provided. A large diameter portion 17b is provided in a portion from the bolt head 17a to the rear cover contact surface of the brush plate 15.

Accordingly, on the side of the positive terminal bolt 16, the plain washer 20 is in contact with the large diameter portion 16b and is tightened with the nut 22 together with the spring washer 21. Therefore, no tightening pressure is applied to the resin brush plate 15 and the insulating collar 19.

On the other hand, on the side of the negative terminal bolt 17, the plain washer 24 is in contact with the rear cover 5, the rear cover 5 is in contact with the large-diameter portion 17 b, and is tightened with the nut 26 together with the spring washer 24. Therefore, no tightening pressure is applied to the resin brush plate 15.

As described above, when the large diameter portions 16b and 17b are provided on the terminal bolts 16 and 17, the metal collar becomes unnecessary, so that the problems at the time of molding and the problems at the time of assembly can be solved.

[0027]

In the DC motor with terminal bolts according to the present invention, the positive terminal bolt is provided with a large diameter portion from the head of the bolt to the inner surface of the bottom of the insulating collar, and the negative terminal bolt is also provided. On the other hand, since a large diameter part is provided from the bolt head to the brush plate rear cover contact surface, a tightening pressure is applied to the resin brush plate and the insulating collar without using a metal collar. You can avoid it. This eliminates the need for a metal collar, which eliminates molding problems and assembly problems.

Further, when the terminal bolt is provided with the large diameter portion, the cost can be reduced by reducing the number of parts. Furthermore, the precision of the length dimension of the large diameter portion of the terminal bolt is higher than that of the metal collar, so that the quality and reliability can be improved.

For the positive terminal bolt, the plain washer is placed between the bottom of the insulating collar and the nut to interpose the plane washer, and for the negative terminal bolt, the plain washer is placed between the rear cover and the nut. By interposing the spring washer, tightening with the nut can be stabilized.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of a DC motor with a terminal bolt according to the present invention.

2 (A) and 2 (B) are enlarged vertical cross-sectional views of a mounting portion of a negative terminal bolt and a positive terminal bolt used in FIG.

FIG. 3 is a vertical sectional view of a conventional DC motor with terminal bolts.

4 (A) and (B) are enlarged vertical cross-sectional views of attachment points of the negative terminal bolt and the positive terminal bolt used in FIG.

[Explanation of symbols] 1 iron yoke 1a bottom 1b bearing support cylinder 2 magnet 3 stator 4 bearing 5 rear cover 5a bearing support cylinder 6 bearing 7 rotor 8 rotary shaft 9 rotor iron core 10 main winding 11 commutator 15 Brush plate made of resin 16 Positive terminal bolt 16a Bolt head 16b Large diameter part 17 Negative terminal bolt 17a Bolt head 17b Large diameter part 18 Bolt through hole 19 Insulation collar 19a Insulation spacer part 19b Cylindrical part 19c Bottom part 19d Bolt through hole 20 Plain washer 21 Spring washer 22 Nut 23 Metal collar 24 Plain washer 25 Spring washer 26 Nut 27 Metal collar

Claims (2)

[Scope of utility model registration request] 1. A positive terminal bolt and a negative terminal bolt are respectively provided by penetrating a portion where a resin brush plate is superposed on a metal rear cover that closes an opening of a yoke, and the positive terminal bolt is A cylindrical bottomed insulating collar that insulates the positive terminal bolt from the rear cover by fitting an insulating spacer portion into the bolt through hole of the rear cover, the rear cover and the brush plate are tightened together with a nut. In the DC motor with a terminal bolt, wherein the negative terminal bolt is provided by body tightening the rear cover and the brush plate together with a nut while the negative terminal bolt is body-grounded to the rear cover, the positive terminal bolt is A large diameter portion is provided from the head of the bolt to the inner surface of the bottom of the insulating collar. Terminal bolt with a DC motor, characterized in that the portion extending from the head to the rear cover contact surface of the brush plate large-diameter portion are provided. 2. A plain washer and a spring washer are fitted to the positive terminal bolt so as to be positioned between the bottom portion of the insulating collar and the nut, and the negative terminal bolt is provided with the rear cover and the nut. The direct current electric motor with terminal bolts according to claim 1, wherein the plain washer and the spring washer are fitted so as to be located between them.