JPS608553Y2 - Servo motor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a servo motor in which the rotational speed of the rotor is controlled while the position of the rotor is sequentially detected by a position detection element such as a Hall element.

In a servo motor, the mounting position of the rotor position detection element with respect to the stator is very important.

Conventionally, the position detection element was usually attached to a small sub-printed board, and this sub-printed board was attached to the stator, and this sub-printed board was connected to the main printed board, which was equipped with a motor drive circuit and was attached at a different location. were connected by lead wires.

However, when using a Hall element as a position detection element, for example, the Hall element is a 4-terminal component, so four lead wires are required to be connected to each Hall element. Double lead connections must be made.

Therefore, wiring work (including soldering) for the lead wires is extremely troublesome.

On the other hand, it is important to make motors thinner, for example, in record players and various other electronic devices.

In the past, motors themselves have become considerably thinner.

However, the electronic components that make up the motor's drive circuit are also very powerful, and the current situation is such that thinner motors, including the motor and electronic components, can be said to be undeveloped. ing.

The present invention has been devised in view of the above-mentioned actual situation, and is intended to provide an effective servo motor that achieves both the above-mentioned wiring simplification and thinning.

An embodiment of a servo motor to which the present invention is applied will be described below with reference to the drawings.

Note) shows a two-phase motor.

First, the motor 1 consists of a rotor 5 with a magnet 4 fixed to the lower surface of a sheet metal yoke 3 fixed to a motor shaft 2, and two sets of magnets 4 fixed to the upper surface of a sheet metal yoke 7 to which a bearing 6 of the motor shaft 2 is fixed. The stator 9 includes a stator 9 and a stator 9 to which coils 8 are attached.

In addition, since both yokes 3 and 7 are constructed of flat sheet metal plates, and the coil 8 has a flat shape, the motor 1 itself
It is thin.

On the other hand, 11 is a printed circuit board whose one end 11a is formed into a substantially triangular shape.

The printed circuit board 11 has a mounting surface 12 on its upper surface and a pattern surface 13 on its lower surface.

On one side of the mounting surface 12, a group of 15 electronic components constituting the drive circuit 14 of the motor 1 is mounted, and on the other side, a group of 17 electronic components constituting the power supply circuit 16 is mounted.

The lead wires 18 of these electronic components 15 and 17 groups are soldered in a predetermined pattern on the pattern surface 13 side.

And pattern surface 13 of one end 11a of printed circuit board 11
Two Hall elements 20, which constitute an example of the position detection element referred to in the present invention, are soldered to the.

At this time, each Hall element 20 has its element body 20 fitted into a positioning hole 22 provided in the printed circuit board 11,
Four terminals 23 are soldered to four wiring patterns 24 formed on the printed circuit board 11, respectively.

In this case, the ground pattern 25 is shared by both Hall elements 20.

Therefore, the wiring between both Hall elements 20 and the drive circuit 14 of the motor 1 is the wiring pattern 24.2 of the printed circuit board 11.
5, and there is no need for wiring between both Hall elements 20 and the drive circuit 14 using lead wires.

Note that 27 is an insulating member having an S-triangular shape, and is made of, for example, synthetic resin.

This insulating member 27 has three elastic locking claws 2B and one locking claw 29 integrally molded at three locations (corners) on the lower surface 27a side and one location on the upper surface 27b side, respectively. has been done.

Further, on the upper surface 27b of this insulating member 27, a pair of recesses 30 for escape from both the Hall elements 20, and a total of four lead wires 31, one pair of each of the two sets of coils 8, are positioned and engaged. Four locking grooves 32 for locking are formed.

Note that at both ends of each locking groove 32 there are triangular protrusions 32 that protrude in opposite directions to prevent each lead wire 31 from floating.
a (see Fig. 4) is integrally molded.

Next, the procedure for assembling the servo motor having the above structure will be explained.

First, the insulating member 27 is placed at a predetermined position on the yoke 7 of the stator 9.
Overlap.

At this time, the three locking claws 28 on the lower surface 27a of the insulating member 27 are inserted into the three positioning square holes 34 formed in the yoke 7 against elasticity, and are locked and positioned.

In this state, each pair of the two sets of coils 8, a total of four lead wires 31, are pulled out and locked into the four locking grooves 32 of the insulating member 27, respectively, as shown in FIG.

However, at this time, each lead wire 31 is positioned within each locking groove 32, and is locked by being folded under both overhanging portions 32a that project in opposite directions at both ends thereof.

Further, the tips of each of these lead wires 31 are soldered to a predetermined wiring pattern of the drive circuit 14 on the printed circuit board 11, respectively.

Then, one end 11a of the printed circuit board 11 is stacked on the upper surface 27b of the insulating member 27 with its pattern surface 13 facing downward.

At this time, the locking pawl 29 is inserted into the square hole 35 formed in the tip portion of one end 11a of the printed circuit board 11 against elasticity, and is locked therein.

Further, the set screw 38 is inserted from above and below into the screw insertion holes 36 and 37 formed in the printed circuit board 11 and the insulating member 27, and the set screw 38 is screwed into the screw hole 39 provided in the yoke 7 and tightened. As a result, the printed circuit board 11 sandwiches the insulating member 27, and the yoke 7 is fixed at a predetermined position.

Further, at this time, the pattern surface 13 of the printed circuit board 11 is brought into close contact with the upper surface 27b of the insulating member 27, and is insulated from the yoke 7.

Also, at this time, both Hall elements 20 are connected to both recesses 3 of the insulating member 27.
0 and accurately positioned in the predetermined position.

Then, by inserting the lower end of the motor shaft 2 into the bearing 6 and assembling the rotor 5 and stator 9, both Hall elements 20 are opposed to the lower surface 4a of the magnet 4 of the rotor 5, and both of them are mutually be approached.

After the above assembly is completed, the mounting surface 12, which is the upper surface of the printed circuit board 11, is directed toward the rotor 5, and the electronic components 15 and 17 mounted on the mounting surface 12 are mounted on the printed circuit board 11. At the same time, as shown in FIG. 2, the yoke 7 of the stator 9 and the rotor 5
The rotor 5 is accommodated in a space H occupied by the gap between the rotor 5 and the height of the rotor 5.

Therefore, apart from the space H, there is no need to consider the height for accommodating the electronic components 15 and 17, including the thickness of the printed circuit board 11, and the height of the entire servo motor can be made very thin (low). I can do it.

Note that when the servo motor having the above structure is incorporated into a record player or other various electronic devices, the motor 1 is screwed to the chassis etc. by the yoke 7 of the stator 9, and the printed circuit board 11 is also secured to the chassis etc. It is stably fixed by nails, screws, or other suitable mechanical fixing methods.

The present invention is constructed as described above, and by first attaching the rotor position detection element to the printed circuit board on which the motor drive circuit is installed, the wiring between the position detection element and the drive circuit is connected. This can be done using a wiring pattern formed on a printed circuit board.

Therefore, there is no need to perform extremely troublesome wiring using a large number of lead wires as in the prior art, and the wiring can be extremely simplified, the assembly work efficiency can be greatly improved, and costs can be significantly reduced.

Also, accidents such as breakage of lead wires are eliminated.

Moreover, according to the present invention, by utilizing the space between the coils attached to the stator yoke and attaching the printed circuit board to the yoke via an insulating member, the printed circuit board is attached to the stator yoke and is attached to the rotor magnet. The height and thickness of the coils are placed in such close proximity that the drive mounted on the printed circuit board is utilized to accommodate the thickness of the printed circuit board within that thickness. Since the circuit is configured so that the electronic components that make up the circuit are housed within the height of the rotor, both the thickness of the printed circuit board and the height of the electronic components are equal to the gap between the stator yoke and the rotor. Since the motor can be housed in the space occupied by the height of the rotor, the height of the entire motor can be made extremely thin, and the motor can be made extremely thin.

Further, according to the present invention, a rotor position detection element is inserted into a positioning hole provided in a printed circuit board for positioning, and a plurality of lead wires drawn from a plurality of coils are provided in an insulating member. By inserting the wiring into the locking groove, the position detection element and the lead wire (height and thickness) can be housed within the thickness of the printed circuit board and insulating member (
Since the gap between the stator yoke and the printed circuit board can be made as small as possible, this can greatly contribute to making the motor ultra-thin.

Furthermore, according to the present invention, since the position detection element can be inserted into the positioning hole of the printed circuit board and accurately positioned relative to the rotor, the rotational position of the rotor can be accurately detected and the height of the motor can be reduced. In addition to improving performance, this method prevents multiple lead wires pulled out from multiple coils from coming into contact with the outside of the rotor's magnets, etc. by locking them in the locking grooves of the insulating member. Since this can be reliably prevented, the safety of the motor is also dramatically improved.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a plan view, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, Fig. 3 is an exploded perspective view of the main parts, and Fig. 4 is a plan view. The figure is a perspective view of the insulating member, FIG. 5 is a partially enlarged bottom view showing the soldering of the Hall element to the printed circuit board, and FIG. 6 is a sectional view taken along the line Vl-VI in FIG. In addition, in the symbols used in the drawings, 1... motor, 5... rotor, 7... yoke,
9... Stator, 11... Printed circuit board, 11a... One end of printed circuit board, 12...
...Mount surface, 13...Pattern surface, 1
4... Drive circuit, 15... Electronic components,
16...Power supply circuit, 17...Electronic component, 20...Hall element, 23...4 terminals, 24...Wiring Hatan, 25...
...Earth pattern, 27...Insulating member, 22
. . . Positioning hole, 32 . . . Locking groove.

Claims (1)

[Scope of utility model registration request] A stator yoke, a plurality of coils attached to the stator yoke, a rotor having magnets facing the coils, and a printed circuit board on which a motor drive circuit and the rotor position detection element are provided. Prepare,
The position detection element is provided at one end of the printed circuit board,
One end of this printed circuit board is mounted on the side of the yoke that faces the magnet so that its patterned surface faces the yoke of the stator, and between the adjacent coils with an insulating member interposed therebetween, and the position detection element is mounted on the side of the yoke that faces the magnet. The printed circuit board is inserted into the positioning hole provided in the printed circuit board for positioning, and the plurality of lead wires drawn out from the plurality of coils are inserted into the locking groove provided in the insulating member and wired. A servo motor characterized in that electronic components constituting the drive circuit provided on a mounting surface of a printed circuit board are accommodated within the height of the rotor.