JPS619161A - Coreless linear dc motor - Google Patents

Abstract

PURPOSE:To obtain a linear motor which has large thrust and high efficiency by opposing a field alternately having N- and S-poles at the prescribed opening width, and an armature having a coreless armature coil formed in the bore width of the conductor in the special size. CONSTITUTION:A field magnet 6 in which N-poles and S-poles are aligned in the prescribed opening width T is formed. A coreless armature coil 3 formed at 2/3 times of T in the bore width of the conductor which contributes to the thrust is formed, a plurality of the coils 3 are aligned at a suitable interval to form an armature. A rectifier 13 which can flow a current to the coils 3 in the width of 2/3 times of T of electric angle is provided, one of the field magnet and the armature is used as a stator and the other is as a movable element to form a linear motor. Thus, it can be controlled freely from low to high speed, and smooth traveling characteristic can be obtained.

Description

[Detailed description of the invention] (Technical field) The present invention relates to a coreless linear DC motor.

(Technical Background) Rotary motors and the like that perform one-rotation motion are generally known as devices for moving objects. In these devices, rotary motors are frequently used for performing rotary motion for multipurpose purposes. Yoha says, -C, big. 5
F16. . ,). In order to cause a linear reciprocating motion of an object by a motor of 0.11, a converter is required to convert the rotational motion energy into linear reciprocating motion energy. Therefore, the linear reciprocating drive device has a complicated structure and is expensive. In this way, various highly efficient motors have been developed to drive objects, but in order to move objects in a straight line, linear motors, which directly perform linear motion, are more effective than motors that perform general rotational motion. is often more desirable, and the effectiveness of this linear motor has been praised for a long time. Inventions and ideas using linear motors in various fields, such as linear motor cars using linear motors, door opening/closing devices, camera shutter opening/closing devices, linear drive devices such as copying machines and drafting tables, etc. As is known, many of these linear motors are linear induction motors, linear pulse motors, or voice coil type IJ motors.
It is a near motor. Linear induction motors are large and expensive, and cannot be driven using a DC power source, making them unsuitable for small devices.

Linear pulse motors have the drawback of large mechanical vibrations and step-out phenomena when driven at high speeds.

Furthermore, according to the linear pulse motor, the stator teeth must be finely formed over the entire moving path of the moving element, making it very expensive, and the stroke length of the moving element cannot be changed to a longer length as necessary. It's troublesome. A voice coil type linear motor is used to drive a head of a magnetic disk, and although it has the advantage of being extremely compact, it has the disadvantage that the magnetic circuit is complicated and the stroke length of the moving element cannot be increased.

For this reason, a linear DC motor is in demand. Such a linear DC motor is useful for use in small devices because (1) it can be driven by a DC power source.

(2) Large starting torque (thrust), good efficiency compared to 31'J near pulse motor etc. (4) Free circuit design from low speed to high speed. For example, in circuit design, linear pulse motor It is also possible to perform step drive as shown in (5) Also, even if the mover runs at high speed, no tax adjustment phenomenon occurs. (6) There is little mechanical vibration. (7)
It has the advantage that it does not require significant machining precision like a linear pulse motor.

However, most conventional linear DC motors are of the iron core type having a stator iron core. For this reason, (1) it is difficult to arrange the position detecting element, and (2) the iron core type causes large coking, making it difficult to run smoothly. (3) Since it is a ferrous core type, it attracts each other with the field magnet, and as a result, it is necessary to use rigid and expensive support mechanisms such as bearings and wheels to support the mover. The disadvantages are the same for linear induction motors and linear pulse motors.) (4) Since they are of iron core type, they are heavy, making assembly difficult and expensive. (5) Even if an attempt is made to change the stator to one with a longer stroke if necessary, there is a drawback in that the stator cannot be easily added to a longer stroke.

To this end, the present applicant has previously provided a number of coreless linear DC motors. Such a coreless linear DC motor has 1 and 2p having magnetic poles alternately N and S.
(p is a positive integer of 1 or more) From a group of armature coils in which the open angle of the conductor part contributing to the thrust is approximately (2n-1) times the magnetic pole width of the field magnet. A conventional linear DC motor was provided, in which one of the two armatures was used as a mover for relative movement, and the other was used as a stator.

Cono coreless linear DC motor has (1) large thrust (
torque), (2) good efficiency, (3) can be driven freely from low to high speeds, and (4) detects the north or south pole of the field magnet to energize the armature coil in the desired direction. (5) coking can be minimized by using an air-core armature coil, resulting in smooth running; (6) the moving element (7) By unitizing the armature, it can be easily changed to various stroke lengths as needed; 8) It has the advantage of being light in weight, with a small number of parts, and can be mass-produced at low cost.

However, the coreless linear DC motor
Since the getter conducts current through an electrical angle of 180 degrees, a large thrust ripple is generated at the boundary between the north and south poles of the field magnet, which has the disadvantage that the running element cannot be moved smoothly. Further, in the above-described 180-degree main energization case, only a small number of armature coils can be disposed in a limited stroke length, so that it is impossible to obtain a smooth thrust ripple and a large thrust force. Yet again. In the above 180 degree main conduction case.

When arranging an appropriate number of armature coils for a limited stroke length, etc., the number of armature coils is limited, so this armature coil cannot be formed by winding a conductor wire in many turns. It has the disadvantage of not being able to obtain large thrust.

(Objective of the present invention) The present invention has the following advantages: (1) Large thrust is not required, (2) Good efficiency, (3) Can be freely driven from low speed to high speed, and (4) In the case of a coreless linear DC brushless motor, The position detection element for detecting the N pole or S pole of the magnetic magnet and energizing the armature coil in the desired direction can be easily installed at a desired position, and (5) coking can be performed using an air-core armature coil. (6) It is possible to use inexpensive support mechanisms such as bearings and wheels that support the slider. , (7) By unitizing the armature, it can be easily changed to various stroke lengths as needed, (8) It is light in weight, has a small number of parts, and can be mass-produced at low cost. 9) By energizing at 120 electrical degrees, smooth thrust ripples can be obtained and the traveling elements can be moved smoothly, and 00) A large number of armature coils can be arranged within a limited stroke length, etc. By obtaining smooth thrust ripple and large thrust 2,
(11) The purpose is to obtain a coreless linear DC motor that can obtain a large thrust by forming the armature coil with multiple turns using a conductive wire. be.

(Means for Achieving the Object of the Present Invention) The object of the present invention is to have N and S magnetic poles alternately having an opening angle width of T along the running direction of the slider (p is a positive integer of 3 or more). A field magnet is provided with a pole field magnet, and an armature consisting of a coreless armature coil formed in which the inner diameter width of the conductor part contributing to thrust is 1/2 or approximately 1/7 width. A rectifying device is provided for supporting the armature coil so as to move relative to the armature coil, and for making the armature coil energized by the width of 100 T or approximately 1 T in electrical angle,
This is achieved by providing a coreless linear DC motor in which either the coreless armature or the field magnet is used as a stator and the other is used as a mover.

The present invention will be described in detail below with reference to the drawings.

(First embodiment of the present invention) A DC brushless motor LM will be explained.

1 and 3 are vertical cross-sectional views of the ones in FIGS. 1 and 2 viewed from the running direction, and with reference mainly to these FIGS. The configuration of the coil type DC linear motor LM will be explained.

A moving coil type linear motor LM having a speed detection mechanism according to the first embodiment of the present invention has a long plate-like magnetic plate 2 fixed on a long plate-like base 1, the width of which is narrower than the width of the base 1, and on top of that
As shown in FIG. 1 and FIG. 4, a long plate-shaped field magnet 6 having a large number of N-pole and S-pole drive magnetic poles 6a alternately arranged in the longitudinal direction, which are magnetized in the thickness direction ζζ, is constructed as shown in FIG. It is permanently installed. The field magnet 6 is formed of field magnet segments forming each magnetic pole, and is connected to the magnetic plate 2.
It goes without saying that the field magnet 6 may be formed as shown in FIG. 4 above. As shown in FIG. 4, on the side surface of the field magnet 6 formed in this way, frequency detection magnetic poles 12 are provided, in which N poles 12a and S poles 12b are alternately magnetized at a fine pitch. . The frequency detection magnetic poles 12 can be formed with a very fine pitch, but the frequency detection magnetic poles 12 can be formed with long lengths as shown in Fig. 4.
Needless to say, the field magnet may be formed into a field magnet that is integrally formed in a plate shape, or the field magnet segment ζ may be formed separately.

A two-character running magnetic yoke 7 is provided opposite to the field magnet 6, and the running magnetic yoke 7 is rotatably supported on the side surface of the running magnetic material yoke 7. It is guided by the side surface of the plate 2 and moves smoothly in the running direction. On the inner surface of the running magnetic yoke 7, three groups of rectangular armature coils as shown in FIG. 5 are arranged adjacently so as not to overlap each other, and a printed circuit board 4 is adhered and fixed to the lower surface thereof. On the printed circuit board 4.

As shown in FIG. 5, a position sensing element 5 (for example, a Hall element, a Hall IC, etc. A conversion element) is disposed by soldering. The armature coil 6 includes conductor portions 3a and 6a that contribute to thrust, a sensing element 5. The position 3o arrangement described above is desirable because it provides a DC linear motor LM with a smooth thrust (torque) ripple, and the advantage is that the position sensing element 5 can be easily disposed at a suitable position, which is convenient in mass production. A coreless armature consisting of the above-mentioned armature coil 6 group is arranged on the inner surface of the magnetic yoke 7, and is configured to move relative to the above-mentioned field magnet in a plane facing direction. Magnetoelectric conversion element 5 which is an element
is opposed to the side surface of the driving magnetic pole 6a of the field magnet 6, collects the leakage magnetic flux of the driving magnetic pole 6a of N or S pole, and outputs an appropriate signal to the semiconductor rectifier (drive circuit) 13. . The magnetoelectric conversion element 5 can be arranged at such a position only when the conductor portion 6b does not contribute to the thrust of the armature coil B.
This is because the radius of the field magnet 6 can be narrowed by the width of . Therefore, a space is created in which the magnetoelectric conversion element 5 can be disposed on the armature side facing the side surface of the field magnet 6. Similarly, under the same conditions as the magneto-electric conversion element 5' (see Fig. 5), a magnetic pole 1 for frequency detection is placed on the side of the armature coil 6 so as to face the frequency detection magnetic pole 12 formed on the side surface of the field magnet B. A magnetic sensor 9° such as a Hall element or a Hall IC for detecting the magnetic pole 12 is arranged on the printed circuit board 4. The frequency detection magnetic pole 12 and the magnetic sensor 9 form a speed detection mechanism.

Therefore, when the moving coil type DC linear motor LM is powered on, current flows in the direction of the arrow F in the three groups of armature coils forming the armature, as shown in FIG. is obtained.

The armature, that is, the running element travels in the direction of arrow F. Note that both terminals of each armature coil group 3 are connected to a semiconductor rectifier 13.
Both output terminals of the magnetoelectric transducer 5 as the position detection element 5 are connected to the above-mentioned armature film 3 and are energized at an electrical angle of 1-T or approximately -y-T, that is, 120 degrees. It is connected to a semiconductor rectifier 13 configured as follows. 14-1 and 14-2 are semiconductor rectifier devices 16, respectively.
The pla! These are the sumi power terminal and the negative power terminal. As is clear from FIG. 6, the armature coil 6 has an inner diameter formed to have an IeT width equal to the magnetic pole width T of the field magnet 6.
Further, each of the three groups of armature coils is arranged so as not to overlap each other. When the field magnet 6 moves in the traveling direction as described above, the magnetic sensor 9 detects the frequency detection magnetic pole 12.
Therefore, the magnetic sensor 9 can obtain a frequency according to the moving speed of the traveling element. By using this n wave number as a position control feedback signal, the speed of the travel element can be controlled.

(Second Embodiment of the Present Invention) In the above embodiment, a moving coil type DC linear motor LM was shown, but a moving field magnet type linear motor in which the field magnet 6 serves as a running element and the armature serves as a stator Needless to say, it can also be used as a motor. in this case,
In the case of the above example, it is sufficient to reverse the arrangement of the field magnet 6 and the armature consisting of the 6 groups of armature coils, so this will not be explained in detail, but such a movable field magnet type DC In the case of a linear motor, it goes without saying that the field magnet 6 facing the armature side does not need to be integral, and may be formed using a plurality or a large number of magnets.

(Third Embodiment of the Present Invention) It goes without saying that the frequency detection magnetic pole 12 may be formed on the 6 faces of the field magnet facing the armature as shown in FIG. In this case, the magnetic sensor 9 may be arranged on the printed circuit board 4 so as to be housed in the cavity within the frame of the armature coil B (fourth embodiment of the present invention). Figure 8 shows the fourth embodiment of the present invention. Exploded perspective view of the main parts of the example, No. 9
The figure is an explanatory diagram of the mover, and in FIG. 10, the field magnet LM' is constructed using a brush and a commutator without using a semiconductor as a rectifier.

Referring to FIGS. 8 and 9, the field magnet 6 is a stator as in the first embodiment, and a commutator 15 is formed in a long plate shape parallel to the field magnet 6.
is fixed. This commutator 15 is formed by etching copper foil along the longitudinal direction on both sides of the upper surface of the printed circuit board 16 formed in the form of a long plate, for example, by etching conductive parts 17-1. -2 is formed.

A field magnet 6 is placed between the conductive parts 17-1 and 17-2.
When the magnetic pole width of is T, a plurality of commutator pieces 18-1, 18-2 are arranged so that one commutator piece formed to a width of 1/2 (or 1/2) is included within the magnetic pole width T. is formed. This commutator piece 18-1.18-2
It is also convenient to form a plurality of commutator pieces 18-1.18- by the same means as the conductive portion 17-1.17-2.
The second group has printed circuit boards 16 arranged at equal intervals (or approximately equal intervals).
formed on the surface. Therefore, community T
The T-stripes 18-1 and 18-2 are spaced apart from each other by - (or approximately an inch). Multiple commutator pieces 18-
The first group is connected to the conductive part 17-1 for the positive power terminal, and the plurality of commutator pieces 18-2 are connected to the conductive part 17-2 for the negative power terminal. It is integrally formed. Said conductive part 17-1.17-
2. A carbon material 19 is formed on the surface of the printed circuit board 16 between the commutator pieces 18-1 and 18-2.

The mover is formed by arranging three groups of armature coils on the surface facing the field magnet 6 on the lower surface of the traveling magnetic material yoke 7' (FIG. 9), as in the first embodiment. It will be done.

A through hole 20-1.20-2 extending in the longitudinal direction is provided at both ends of the traveling magnetic yoke 7', and a bearing 21-1 is provided at the inner circumference of the through hole 20-1.20-2. .21-
2 is formed.

Each of the through holes 20-1 and 20-2 has two
Guide bars 22-1 and 22-2 whose ends are fixed to the fixed side by means not shown are attached to the bearing 21.
-1.21-2 is inserted and lowered in sliding contact. Therefore,
The traveling magnetic yoke 7' having a plurality of armature coils 3 is connected to guide bars 22-1, 22- so that the armature coil 6 group and the field magnet 6 can move relative to each other.
2+ Travels while being guided. This armature coil 3
In this case, three magnetic yokes are disposed on the lower surface of the traveling magnetic yoke 7' in close contact with each other so as not to overlap with each other. The armature coil 6 is as follows.

It is formed into a rectangular frame with a planar hollow core.

The inner diameter width of the conductor parts 6a and 6a that contribute to the thrust is 2L@T
(or approximately S.T.) wide. The reason for doing this is already mentioned above (or almost Ding/T)
This is to enable width energization, that is, 120-degree main energization, without employing a special electrical circuit configuration.

In particular, in the case of the fourth embodiment, since the rectifier is constructed using a brush and a commutator in spite of using a semiconductor, it is different from the first to third embodiments.
), unlike the case of 1, it is inconvenient to carry out 120-degree current conduction in an electric circuit due to high cost, and it is useful for products that must be formed at low cost.

The same number of brushes 23 as the armature coils 3 are provided on the running magnetic yoke 7' on the side surface of the armature coil 3 group, and the brushes 23 are in sliding contact with the commutator 15 consisting of the commutator pieces 18-1 and 18-2 groups. That's what I do. Bren 23 is
Since it is desirable to avoid contact with both commutator pieces 18-1 and 18-2 when located at the center between the commutator pieces 18-1 and 18-2, it is formed to have one width. The brush 23 is connected to the commutator piece 18-1.1.
Since it is necessary to make sliding contact with the brush 8-2, a desirable method for this purpose is to press the brush 23 using a coil spring 24.

For this purpose, a cylinder 25 made of a non-magnetic material is attached to the traveling magnetic yoke 7', and a conductive pin 26 is attached to it.
One end of the coil spring 24 made of a conductive material is brought into contact with the brush 2, and the other end of the coil spring 24 is brought into contact with the brush 2.
It comes in contact with 3. One end of the conductive pin 26 connects three armature coils 6-1. ..., one terminal 3 of 6-6
-18, 3-2a, and 3-38. Therefore,
Armature coil 3-1. ..., one terminal 3- of 3-6
1 am..., 3-3a is the conductive pin 26. Coil spring 24. Brush 23. Commutator piece 18i.

18-2 or the carmen material 19. The armature coil 3-1. ..., 6-6 in a predetermined direction to obtain a thrust in a predetermined direction according to Fleming's left-hand rule (see FIG. 10).The three armature coils 6-1. As is clear from FIG. 10, the other terminals of the motors 3-6 are commonly connected to form a three-phase moving coil type linear motor DC motor LM'.

(Fifth Embodiment) In the moving coil type linear DC motor in the fourth embodiment described above, the commutator was provided with a brush on the mover side and a commutator consisting of a group of commutator pieces on the stator type, but the stator side Brush on.

It goes without saying that a rectifier comprising a group of commutator pieces on the movable element side may also be used.

(Sixth Embodiment) Based on the fourth and fifth embodiments above, it goes without saying that a moving magnet type linear DC motor may be used, with the armature coil group side serving as a stator and the field magnet side serving as a mover. .

(Seventh Embodiment) In the above embodiment, an example of a linear DC motor is shown in which the stator is formed long and the mover is formed short, but it goes without saying that the reverse may be used.

(Effects of the Invention) As is clear from the above, it has the features of the coreless linear DC motor described above, and (1) has an electrical angle of 120
Since it is energized at the same time, a smooth thrust ripple can be obtained, and the traveling element can be moved smoothly. (2) Since a large number of armature coils can be arranged within a limited stroke length, etc., smooth thrust ripples can be achieved, and a large thrust can be obtained. (3) Armature coils Since it can be formed by winding the conductor wire in many turns, a large thrust can be obtained. Because of this effect, it is possible to obtain a coreless linear DC motor with good performance and efficiency.

[Brief explanation of the drawing]

Fig. 1 is a top view of a moving coil type linear DC motor having a speed detection mechanism according to the first embodiment of the present invention, Fig. 2 is a side view of Fig. 1, and Fig. 3 is the same as Figs. 1 and 2. FIG. 4 is a perspective view of a field magnet in which a frequency detection magnetic pole having a speed detection mechanism forming part is formed;
Fig. 5 is a perspective view showing the arrangement of the position detection element and the shape of the armature coil, Fig. 6 is a developed view of the field magnet and the armature coil group, and Fig. 7 is a perspective view showing the arrangement of the position detection element and the shape of the armature coil. FIG. 8 is an exploded perspective view of the main part of the fourth embodiment of the present invention, and FIG.
FIG. 10 is an explanatory view of the mover in the figure, and FIG. 10 is a developed view of the field magnet and armature. LM, LM'... Moving coil type linear DC motor, 1.
... Base, 2... Magnetic plate, 3... Armature coil. 4... Printed circuit board, 5... Position fatigue element, 6
... Field magnet, 7... Traveling magnetic yoke. 8... Traveling roller, 9... Magnetic sensor,
12... Magnetic pole for frequency detection, 13... Semiconductor rectifier, 14-1°°° frass power supply terminal, 14-
2... Minor 2... Commutator piece, 19.
・・Power-zen material. 20-1.20-2...Through hole% 21-1.21-
2...Bearing, 22-1.22-2...Guide bar, 23...Brush, 24...Coil spring. 25... Cylinder, 26... Conductive pin.

Claims (1)

[Claims] 1. N having an opening angle width of T along the running direction of the mover;
A p-pole field magnet (p is a positive integer of 3 or more) having S magnetic poles alternately is provided, and the inner diameter width of the conductor part contributing to the thrust is 2/3 T or approximately 2/3. - An armature consisting of a coreless armature coil formed to a T width is provided and supported so as to move relative to the field magnet, and the armature coil has the above 2/3 T or approximately 2/3 in electrical angle.・T
1. A coreless linear direct current motor, characterized in that a rectifying device is provided for wide-width conduction, and either the coreless armature or the field magnet is used as a stator, and the other is used as a mover. 2. The above coreless armature coil has an inner diameter width of 2/3·T or approximately 2/3·T between the conductor parts that contribute to thrust.
2. The coreless linear DC motor according to claim 1, wherein the coreless linear DC motor is of an air core type having a width. 3. The coreless DC linear motor is a three-phase coreless linear DC motor having one or more sets of three coreless armature coils. The coreless linear DC motor described in item 2. 4. The coreless linear DC motor according to claim 3, characterized in that a plurality of sets of the three coreless armature coils are arranged at appropriate intervals. 5. The coreless linear DC motor according to any one of claims 2 to 4, wherein the coreless armature coils are arranged so as not to overlap each other. 6. A patent claim characterized in that the rectifier is a semiconductor rectifier including a magnetoelectric conversion element for energizing the armature coil in a predetermined direction by detecting the N pole or S pole of the field magnet. The coreless linear DC motor according to any one of the ranges 1 to 5. 7. The rectifying device includes a commutator and a brush, and one of the commutator and the brush is provided on the field magnet side, and the other is provided on the armature side. The coreless linear DC motor according to any one of Item 5. 8. The above commutator is 2/3・T or almost 2/3・
The coreless linear linear system according to claim 1, wherein the linear linear system is formed such that one commutator piece is formed within the opening angle width T, each having a width T. DC motor. 9. The coreless linear DC motor according to claim 7 or 8, wherein the plurality of commutator pieces are arranged at equal or substantially equal intervals. 10. In the above commutator, every other commutator piece group forming the same is connected to the positive side power terminal, and the commutator pieces group between the commutator pieces connected to the positive side power terminal are connected to the negative side power terminal. 10. The coreless linear DC motor according to claim 9, wherein commutator pieces connected to the positive power terminal and commutator pieces connected to the negative power terminal are alternately formed. 11. The coreless linear DC motor according to any one of items 7 to 10, wherein the brush is formed to have a width of T/4.