JPH0314022Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a printed coil unit for an actuator that is ultra-thin, compact, and low in cost. The actuator here consists of a coil, a magnetic circuit, etc., and converts electrical energy into mechanical energy using electromagnetic force.
For example, motors, rotary actuators,
Indicates a linear actuator, linear motor, etc.

[Conventional technology]

In recent years, as audio equipment, video equipment, OA equipment, etc. have significantly advanced and become smaller and thinner, it has become desirable for the motors and actuators used in these equipment to be smaller and thinner. In general, motors and rotary actuators that aim to be small, especially thin, are divided evenly in the circumferential direction.
What is desired is a structure consisting of a magnetized rotor and a stator coil that is divided and wound in correspondence with its magnetic poles.

Also, recently, so-called printed coils, which are made by applying photolithography technology, have come into use. Especially when it comes to linear actuators where the distance (gap) between the magnet and yoke plate is less than 2m/m, motors and rotary actuators whose diameter is less than 30m/mφ and gap is less than 2m/m. With wire-wound coils, assembly such as winding the coil thinly and connecting spiral conductor patterns to each other is extremely difficult, and the coil is also expensive.

In such a printed coil, the coils can be arranged uniformly and theoretically over the entire effective area, and therefore the thickness can be kept small. Arranging the coils uniformly over the entire effective area in this way is called distributed winding.

[Problem that the invention seeks to solve]

However, such printed coils are used in small and thin motors and actuators by taking advantage of the above characteristics, but these small and thin motors and actuators are equipped with elements for detecting the position of magnets placed opposite each other, such as Hall elements. The volume ratio of an element with a magnetic detection function, such as a magnetoresistive element, to the coil becomes very large, making it difficult to arrange it inside the motor. For example, if you try to place it on top of a coil, you would have to make the air gap large so that it would not catch on to the magnet placed opposite it, which would prevent you from taking advantage of the printed coil's ability to be wound thinly, and also reduce the main magnetic flux of the magnet. If placed outside, the magnetic detection sensitivity decreases, and a high sensitivity ratio of an amplifier for the magnetic detection element is required, making it difficult to obtain a good S/N ratio and increasing costs.

[Means and actions to solve the problem]

The present invention relates to a small and thin coil unit for an actuator that solves the above problems.

That is, the present invention is a printed coil unit comprising a printed coil having a spiral conductor pattern, which includes at least one printed coil in which a magnetic detection element is arranged in the center of the spiral conductor pattern. Generally, the part of a motor or actuator that is made up of coils is called a coil unit.In the case of a coil unit that uses printed coils, it may be made up of a single printed coil, or
A coil unit may be constructed by stacking a plurality of printed coils.

The printed coil used in the present invention may be manufactured by any manufacturing method, such as etching, plating, or a combination of these methods. Preference is given to printed coils produced by the described production method. The size can be any size, but if it is a motor or rotary actuator, the diameter is 5 to 40 m/mφ, and the thickness is 0.1 to 2.
m/m is particularly effective. Also, in motors, rotary actuators, linear actuators, etc., the linear density of the coil part is 2 to 20 wires/
mm, more preferably 5 to 20 pieces/mm. Usually, the spiral pattern is formed on one or both sides of the printed coil support, and if necessary, the conductor patterns on both sides of the printed coil support are connected to each other by through holes so that they are electrically conductive. . The printed coil support may be of any material as long as it has electrical insulation properties, and for example, glass epoxy substrates, polyimide films, epoxy resins, etc. are preferably used. Further, any method may be used to form the through hole.

The coil pattern may be any number of poles, from 1 pole (Fig. 6) to 2 poles, depending on the number of magnetized poles of the counter-pole magnet of the motor or rotary actuator.
Pole (FIG. 5), four poles, six poles, eight poles (FIG. 1) or more are also conceivable. The shape of the conductor pattern may be a circle, a circle, a rectangle, or a combination thereof, but a fan shape with rounded corners is often used in flat type motors. In either case, a land for external connection or through-hole where the end of the spiral is maintained in the center of the spiral,
Provide a hole to attach the magnetic detection element. Furthermore, not only one magnetic detection element but also a plurality of magnetic detection elements may be attached to one central part of the spiral conductor pattern. The magnetic detection element mounting hole may be formed at the same time as the printed coil is manufactured, or may be formed by pressing or the like after the printed coil is completed.

The magnetic detection element may be anything that can detect magnetism, such as a Hall element, a microcoil, a magnetoresistive element, etc.

Any material may be used to fix the magnetic detection element to the magnetic detection element hole of the printed coil, but for example, epoxy or phenol adhesive may be used.

The printed coil obtained as described above may be used as a single coil unit, or the printed coil described above and a printed coil not containing a magnetic detection element may be laminated. Any material can be used for this lamination as long as it can fix the coils and provide insulation between the coils, but for example, the adhesive used to fix the magnetic sensing element mentioned above can also be used, or it can be glued on both sides of the insulating film. An adhesive sheet coated with a semi-cured adhesive may also be used.

〔effect〕

The coil unit incorporating the ultra-thin magnetic sensing element of the present invention can form a magnetic circuit with high magnetic flux density, and as a result, a small, thin, high-output motor or linear actuator can be obtained at low cost.

[Brief explanation of the drawing]

FIG. 1 is a plan view of one embodiment of the printed coil used in the present invention, and FIG. 1A is a front plan view;
Figure 1 B is a back side plan view, Figure 2 is A- of Figure 1.
3 is a plan view of one embodiment of the printed coil unit of the present invention, FIG. 4 is a sectional view taken along the line B-B' of FIG. 3, and FIG. 5 is a sectional view of the printed coil unit of the present invention. Plan view of another embodiment of the printed coil unit FIG. 6 is a plan view of still another embodiment of the printed coil unit of the present invention. In the figure, 1 and 1' are printed coils, 2 and 2' are printed coil supports, 3 is a spiral conductor pattern, 4 is a through-hole land,
Reference numeral 5 indicates a central portion, 6 a through hole, 7 and 7' external connection terminals, 8 a magnetic detection element, 9 and 9' an insulating resin, 10 an adhesive layer, and 11 a printed coil unit.

Claims (1)

[Scope of utility model registration request] In a printed coil unit consisting of a printed coil having a spiral conductor pattern 3, at least one printed coil 1 has a magnetic detection element 8 disposed in the center 5 of the spiral conductor pattern 3.
A pre-coil unit characterized by comprising: