JP2005080495A - Toroidal coil linear motor and syringe pump driver employing it as drive source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive high thrust linear motor having a simple structure. <P>SOLUTION: Relatively movable armature and cylindrical member and their holding shaft are arranged concentrically, the armature is formed of a ring coil and a magnetic body and a plurality of unit armatures each having a pair of armature yokes for clamping the toroidal coil are arranged coaxially. Each armature yoke is provided, on the inner circumferential surface thereof, with annular magnetic teeth protruding/recessed alternately in the axial direction and the cylindrical member facing the magnetic teeth through a small air gap is provided with annular pole teeth protruding/recessed alternately in the axial direction. When a current is fed to the toroidal coil of the armature, the armature and the cylindrical member can move freely. The invention is especially applicable to a linear stepping motor and a compressor. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a linear motor that can be used in medical equipment, automobiles, and housing facilities.

As the linear motor, there are many single-sided opposed types in which the stator and the moving element are planarly opposed as shown in FIGS. 6A and 6B of the prior art.
6 (A) and 6 (B) of the above-described prior art, in order to move the moving body linearly while ensuring an air gap, in addition to thrust in the moving direction, an electromagnetic attracting force perpendicular to the moving direction (commonly side pull) Called), and a large stress is applied to the bearing and the like, and it is necessary to adopt a guide mechanism for the moving body and an expensive linear bearing, and the structure of the guide mechanism is a complicated and expensive actuator.

  As seen in FIG. 7 of another prior art, an annular coil cylindrical configuration having a permanent magnet type on the armature side is also known. In the permanent magnet type cylindrical linear stepping motor, a unit armature is constituted by an annular coil and an armature yoke provided so as to surround the annular coil, and is arranged coaxially with an annular permanent magnet magnetized in the axial direction interposed therebetween. The two unit armatures form the armature, but the efficiency is improved because they have permanent magnets, and the electromagnetic attraction force in the direction perpendicular to the thrust in the moving direction is not generated. In the configuration, the guide mechanism of the moving body has a complicated structure and is an expensive actuator.

Many of the air conditioners for automobiles have the structure shown in FIG. 8, and the structure is complicated. The engine is driven and driven, but it is not suitable for electric vehicle applications.

Japanese Patent Application No. 10-191619 Linear stepping motor

1) Description In the conventional technology, in the single-sided configuration, the moving body moves linearly while securing an air gap, so in addition to the thrust in the moving direction, an electromagnetic attraction force perpendicular to the moving direction (commonly called side pull) This may cause a great stress on the bearing and the like, and the actuator is complicated and expensive due to the use of a guide mechanism of the moving body and an expensive linear bearing.
2) Although illustration is omitted, in the double-sided type, the above-mentioned side pull is eliminated, but the air gap is distributed and arranged in two places, so it is difficult to prevent dust from entering the air gap, and the automobile has a lot of dust. It was not suitable for driving a robot installed in a place where equipment or the environment was contaminated.
3) Due to the complexity of the moving element support mechanism, linear motors are generally more expensive actuators than rotary motors.
If it is not a ring coil, a useless coil part will generate | occur | produce and it cannot be said that volume ratio thrust is good.
4) Since permanent magnets are more expensive than iron etc., those using permanent magnets for the mover are expensive and suitable for high thrust, but annular coils that do not use permanent magnets in fields that require low prices. There was strong demand for linear motors.
5) Development of a direct electric air conditioner for electric vehicles was required.

  Further, the permanent magnet type cylindrical linear stepping motor shown in FIG. 8 has a permanent magnet on the armature side, so that the efficiency is improved and no electromagnetic attractive force in the direction perpendicular to the thrust in the moving direction is generated. Therefore, although a powerful mechanism and linear bearing as opposed to the surface-facing type are not required, the configuration of FIG. 8 described above does not change the structure of the guide mechanism of the moving body, and it is an expensive actuator. It was.

(Means 1)
In a linear stepping motor in which a relatively movable armature and a cylindrical member and a shaft for holding the armature are concentric, the armature is formed of an annular coil and a magnetic body so as to sandwich the annular coil. A plurality of unit armatures having a pair of armature yokes provided are coaxially arranged, and each of the armature yokes has annular magnetic teeth having alternating irregularities in the axial direction on the inner peripheral surface thereof. A cylindrical member that is opposed to the inner peripheral surface of the armature via a small gap, and that has a cylindrical permanent magnet on the outer peripheral surface, and the cylindrical permanent magnet has annular magnetic teeth that are alternately concave and convex in the axial direction. Comprising the armature and the cylindrical member so as to be relatively movable by energizing the annular coil of the armature, or

(Means 2)
In the annular coil permanent magnet linear stepping motor according to means 1 or 2, the armature is integrated with the housing and the shaft to form a stator, and the cylindrical member is configured to be movable with the shaft as a guide, Or

(Means 3)
4. An annular coil permanent magnet type linear stepping motor according to any one of means 1 to 3, wherein P is an odd number of 3 or more, an armature is composed of P unit armatures, and a plurality of the annular magnetic teeth are arranged. When the installation pitch is τ, τ is substantially the same as the annular magnetic tooth pitch of the cylindrical member, and when the annular magnetic teeth facing each other and the magnetic pole of the cylindrical permanent magnet face each other in one phase, , At least τ / P misaligned, or

(Means 4)
In the annular coil linear stepping motor according to any one of means 1 to 3, in place of the armature provided outside and the cylindrical member provided inside, a cylindrical member provided outside and an armature provided inside Configured to be, or

(Means 5)
In the annular coil type linear stepping motor according to any one of means 1 to 4, when the number P of armatures is 3, the three annular coils are configured to operate by star or delta connection three-terminal drive. Or

(Means 6) An armature serving as a stator and a cylindrical member serving as a mover, and a linear stepping motor in which a fixed shaft for holding the armature is concentric, and the armature is formed of an annular coil and a magnetic material. Two unit armatures having a pair of armature yokes provided so as to sandwich the annular coil are sandwiched between the permanent magnets magnetized in the axial direction, and are arranged coaxially. The inner peripheral surface has annular magnetic teeth with alternating irregularities in the axial direction, is opposed to the inner peripheral surface of the armature via a small gap, and the outer circumferential surface is cylindrical and has annular annular irregularities in the axial direction. A magnetic cylindrical member having magnetic teeth is provided, and the inner peripheral portion of the cylindrical member is fitted to the outer peripheral portion of the fixed shaft and can be moved by energization of the annular coil of the armature. Annular coil type linear stepping motor .

(Means 7)
The structure of the annular coil linear stepping motor described in the means 1 to 7 is configured as an annular coil permanent magnet linear motor that detects the position and moving speed of the slider and excites the next phase at a predetermined timing. Or

(Means 8)
When applied to a syringe pump driving device or a cylinder type compressor driving device using the annular coil type permanent magnet type linear motor described in the means 1 to 7 as a driving source, it has excellent advantages compared with the conventional mechanical type. One-cylinder, one-linear motor type compressor driving devices have significant advantages such as one-cycle intake / exhaust stroke, multiple phase difference driving, and variable output with stroke change.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of a cylindrical annular coil permanent magnet linear stepping motor according to an embodiment of the present invention, and FIG. 2 is a front sectional view of the example of FIG. Reference numeral 1 denotes an armature yoke made of a magnetic material, which has a large-diameter cylindrical portion and a small-diameter cylindrical portion having a U-shaped cross section.

  In the armature yoke 1, the large-diameter cylindrical portion may be replaced with a casing, and the small-diameter cylindrical portion may be removed and only the inner peripheral surface of the bottom disc. Is preferably provided.

  The armature yoke 1 constitutes a unit armature that is coaxially disposed so that the large and small diameter cylindrical portions face each other and surround the annular coil 2. A predetermined number of unit armatures are coaxially connected via the non-magnetic body 3 and are integrally held by the housing 4 to form an armature. In the illustrated example, the number m of magnetic teeth on the inner peripheral surface of the armature yoke is 2, and the number P of unit armatures is 3. P is an odd number of 3 or more. A shaft 5 is fastened and fixed to the housing 4.

When thinning in the axial direction is required, such as m = 2, as described above, it is not always necessary to provide a large / small diameter cylindrical portion extending in the axial direction from the outer / inner peripheral edge of the disk bottom, but m = 3 or more In this case, it is desirable to provide a large and small diameter cylindrical portion that extends, from the viewpoint of securing the coil amount. The armature yoke 1 having a large and small diameter cylindrical portion shown in FIG. 1 is suitable for sintering from its shape by a magnetic member.
Moreover, it is desirable to use the nonmagnetic material 3 inserted between the unit armatures in order to make the magnetic path of each phase independent.

One of the features of the present invention is that the movable element performs a linear operation using the fixed shaft 5 as a guide. Reference numeral 6 denotes an annular convex tooth portion of the magnetic material, 7 denotes the bottom of the magnetic material, and 8 denotes a bearing such as a sleeve metal. These 6, 7, and 8 are integrated to form a moving element, which slides on the outer periphery of the fixed shaft 5 and the bearing 8, and allows linear operation while maintaining an air gap with the armature yoke 1.

At this time, the radial suction force between the armature yoke 1 and the pole teeth 6 is opposed to the entire circumferential portion and is canceled. Therefore, no load is applied to the bearing, and a sleeve metal can be used. The cylindrical member is slidably held with respect to the shaft 5 by a sleeve-like bearing 8 made of resin, oil-impregnated metal, etc. with little friction, and is configured so that linear reciprocation can be performed with the shaft 5 as a guide. A simple and inexpensive linear motor can be realized.

  In the above-described configuration, since the annular coil 2 is used for exciting the armature, the structure of the armature is very simple, and it is not necessary to use an expensive linear bearing or the like as described above, and linear motion is achieved. As an air gap securing means for this purpose, no separate linear guide mechanism is required, and the central fixed shaft of the cylindrical linear motor is used as a guide, so that an inexpensive linear motor can be obtained.

Further, the advantage of the cylindrical linear motor as seen in the present invention is that the radial force in the direction perpendicular to the moving direction (generally Side)
(also referred to as “pull”) is canceled, and therefore the radial load applied to the bearing is extremely small. Further, FIG. 1 shows a case of three phases, and since it is not affected by the third harmonic of the current, the vibration thrust becomes smaller than that of the two phases, resulting in a low vibration linear motor.

Here, the advantages of the present application can be understood by describing FIG. 6 of the conventional structure. FIG. 6A is a side view of the conventional structure, and shows only the armature yoke 40 and the coil 41, and the magnetic material tooth portion 42 and its holding portion 43. 41 and 42 are relatively left and right. Linear movement is possible. (B) is a view seen from the linear movement direction. The holding portion 43 is supported by a bearing 44 so as to be movable, and the shaft 45 of the bearing 44 is fixed to the frame 46. This structure has the following problems.
1) The armature yoke 40 and the tooth portion 42 have a problem in life because they have an attractive force acting in a direction perpendicular to the moving direction and give an excessive stress to the bearing 44, and have become a factor of noise vibration.
2) The gap facing area is small compared to the total motor volume, and the thrust is small compared to the cylindrical annular coil type.
3) The structure was complicated and expensive.
4) When using it in a dusty place, the entry of dust into the air gap is a problem and the dustproof structure is difficult.
The above problems are those of the present application, and can all be solved.

It will be described that the cylindrical linear motor according to the present invention is suitable for miniaturization and higher efficiency as compared with the structure of FIG. 6 and the like described above. The motor volume of a linear motor having a square shape with one side D and a length L is V = D ²
L. In this case, the air gap facing area S between the stator and the mover is S1 = DL. On the other hand, in a cylindrical linear motor having the same outer diameter D and length L, the air gap facing area is S2 = (π / 2) DL, where the average diameter of the air gap is D / 2. , S2 / S1 = 1.57 times, and the thrust is also proportional to the opposing area, so that the cylindrical linear motor can provide higher thrust and higher efficiency. The conventional face-to-face type (described later as FIG. 6) has a square coil, and the coil portion in the moving direction of the slider does not contribute to thrust, but the annular coil has high efficiency because all the coil portions contribute to thrust. You can also.

  FIG. 3 is a diagram for explaining the magnetic pole relationship between the stator and the mover in the example of FIG. It is composed of three phases of U phase, V phase, and W phase, and 1) in FIG. 3 shows a case where the U phase is magnetized. Actually, the three annular coils have three-terminal input star connection in which the winding ends of each coil are short-circuited, the U-phase winding end and the V-phase winding start, the V-phase winding end and the W-phase winding start, and the W-phase winding. Two-phase or three-phase excitation drive can be performed as a three-terminal input delta connection at each connection point between the end of winding and the start of winding of the U phase.

  However, since the figure becomes complicated, FIG. 3 shows a state in the one-phase excitation drive. The coil is a toroidal annular coil, and the annular coil is sandwiched between two pairs of armature yokes made of a magnetic material. The armature yoke inner peripheral surface is provided with annular magnetic teeth with axially alternating irregularities.

  In FIG. 3, the U-phase is magnetized by the U-phase coil current in 1), and the magnetic poles of the mover face each other through a small gap. At this time, the V phase is opposed to the pole teeth of the cylindrical slider by τ / P as the pole teeth pitch τ of the cylindrical slider. P is an odd number of 3 or more. In the case of FIG. 3, P is 3, and τ = 2π, and 2π / 2 * 3 = π / 3 are opposed to each other. This deviation becomes a stepping amount, and advances by 1 / P of the pole tooth pitch τ. In 2) of FIG. 3, the V phase is magnetized and advances from the state of 1) by π / 3. In 3), the W phase is magnetized and further advances from the state of 1) by π / 3. Next, return to 1) and further advance by π / 3. By repeating this below, linear driving becomes possible. Since P is the number of phases, the phase advances by 1/3 of the pole tooth pitch τ in 3 phases and 1/5 in 5 phases. In this case, the pole tooth pitch τ of the cylindrical member is basically the same as the concave and convex annular magnetic tooth pitch provided on the inner circumference of the armature yoke, but may slightly differ when cogging force is weakened. In the present application, the pitch is substantially the same.

FIG. 4 uses an annular coil 22 for the armature of the moving element 25 and the stator, and the shape of the armature yoke 21 is the same as that in FIGS. 1 and 3, but the stator is limited to two phases. The difference lies in having a permanent magnet 23 magnetized in the axial direction between one phase and two phases. Reference numeral 25 denotes a fixed shaft, and the movable element 25 can perform a sliding linear operation. Reference numeral 37 denotes a housing, which fixedly supports 31 and 36.
This two-phase cylindrical permanent magnet type linear motor makes it possible to move a magnetic cylindrical member having teeth on its outer periphery with a fixed shaft as a guide. The structure is simple, inexpensive and uses a permanent magnet, so it has a large thrust. A linear motor having The operation as the stepping motor of FIG. 4 will be briefly described. The left side of the permanent magnet 23 is magnetized to the N pole in the rightward direction and the right side is magnetized to the S pole. Now, when the left coil 22 is energized and the left yoke 21 of the coil is magnetized to N polarity, the magnetic flux of the permanent magnet passes through the left yoke 22 of the 22 and the moving element 24 faces the teeth. Then, the magnetic flux that has entered 24 forms a magnetic circuit that returns to the S pole of 23 through the teeth facing each other 1/2 of the two armature yokes 23 on the right side of 23. When the excitation of the coil 22 is sequentially moved at a position where the teeth are fully opposed, the moving element 24 is moved by 1/4 of the tooth pitch.

Here, FIG. 7 of the prior art will be described with respect to FIG. The same parts as those in FIG. 4 are given the same numbers, and the description of those parts is omitted. Reference numeral 27 denotes a member which can move relative to the armature yoke 21 having teeth on the outer periphery of the magnetic cylinder. The mechanism for this linear movement is a relative movement mechanism between 21 and 27 as shown in FIG. Flakes, linear bearings, and the like are necessary, resulting in an expensive linear motor. For example, since teeth are provided on the outer periphery of 27, it is difficult to receive and slide the outer periphery with a bearing, and a complicated mechanism is required. If this uses the fixed shaft of the present application as a guide, the structure is simple and inexpensive.

In the configuration of the present application, it is needless to say that the armature side having the annular coil can be operated as a mover and the cylindrical member side as a stator, and therefore illustration and detailed description are omitted. Further, the linear stepping motor described above can be an inexpensive brushless linear motor by detecting the position and speed of the moving element and switching the coil current at an optimal timing.

FIG. 5 is a cross-sectional view showing another configuration of the present invention in which a compressor and a cylindrical annular coil linear motor of the present invention are integrally combined as an application of a linear motor. 5, 30 is a stator having an annular coil shown in a three-phase system, and 31 is a mover that slides on the outer periphery of the fixed shaft 32 and moves to the left and right. The fixed shaft 32 and the stator 30 are fixed to the housing 33. Reference numeral 34 denotes a piston which is fixed to the moving element 31 and is driven by the movement of the moving element to slide on the inner periphery of the cylinder 35 to reciprocate. 36 is an intake duct, and a valve is not shown, but when the piston 34 is moved in the right direction, the intake air in the direction of the arrow is passed, and when the compression process is performed when the piston 34 is moved in the left direction, the valve is closed. It has become. An exhaust duct 37 has an exhaust valve (not shown), and has a function of closing at the time of intake and opening, for example, above a certain compression. If an evaporator etc. are attached to 36 and 37, for example, it will become a simple air conditioner in such a structure. A compressor driving device that drives one cylinder with a single linear motor, wherein one cycle of the linear motor performs intake and compression exhaust.
When the compressed gas is expanded rapidly, the gas cools and absorbs the surrounding heat to cool the surroundings. The housing 33 has a cylindrical shape, and the piston 34 and the cylinder 35 are also circular, so that the connection is easy and can be made compact. In addition, for example, automobiles tend to increase in number of electric cars due to environmental problems, and accordingly, air conditioners for automobiles become electric. Also, when it is in the direct drive trend, this linear motor driven air conditioner can be said to be on the flow.

The number of linear motor driven air conditioner compressors of the present configuration shown in FIG. 5 may be one, but a more constant cooling effect can be obtained by supplying gas to the evaporator by changing the drive phase of a plurality of compressors. become. In this case, changing the phases of the plurality of linear motors is easy because they are electrically controlled, and the compression ratio for determining the output is also simple for a linear motor, and is driven by one linear motor per cylinder. In the compressor driving apparatus having the above configuration, the driving linear motor is suitable for the cylindrical motor of the present application, but other linear motors can exhibit advantages over the conventional mechanical type. On the other hand, as will be described next with reference to FIG. 8, the linear motor has an advantage that these controls can be carried out very easily as compared with the conventional mechanical wobble system.

In contrast to FIG. 5 of the present application, FIG. 8 is a conventional mechanical automobile compressor. 50 is a wheel of an electromagnetic clutch driven by the power of the engine, 51 is a load side wheel that receives the power of 50, and the excitation coil 52 constitutes an electromagnetic clutch. When the compressor is driven, the coil 52 is energized, the pressures 50 and 51 are pressed, and the 51 is rotated. 51 is provided with a disk 53 which is inclined and attached, and pistons 55 and 56 are attached via 54 hard balls. The number of these pistons is not limited to two, but many are five to eight. 57 is a cylinder. The intake and exhaust ducts have the same function as the present application. In FIG. 8, the piston 55 shows the maximum intake and 56 shows the maximum compression state. In this way, the phase of each piston is made of an inclined disk 53, and its output is also changed by changing the compression ratio according to the degree of this inclination. However, this inclination cannot be set and changed for each product. In this respect as well, the output can be freely changed even in the middle of a linear motor. In addition, since this mechanical type involves complicated wobble operation, the linear motor type is superior in terms of life.

  The cylindrical coil permanent magnet type linear motor having a cylindrical shape as described above is also useful as a drive source for the syringe pump because the cylinder and piston used in the syringe pump are cylindrical, and is compact. A syringe pump drive system can be realized.

Instead of the annular alternating irregular magnetic teeth of the moving element shown in the above 1 and FIG. 3, the aforementioned irregular annular magnetic teeth pitch is set to the N pole S pole pitch on the outer periphery of the cylindrical permanent magnet. That is, a linear stepping motor and a linear brushless motor having a moving cylindrical member in which N poles and S poles are alternately magnetized and having a convex-to-convex pitch of a pole pair pitch of N poles to N poles as a driving source The cylinder type compressor drive shown in FIG. 5 is operable.

The annular coil permanent magnet linear motor according to the present invention as described above can achieve the following excellent effects.
1) Since the air gap between the stator and the mover that is cylindrical is also cylindrical, the facing area can be made approximately 1.5 times larger than the flat plate gap, which is advantageous for high thrust.
2) Since it is an annular coil, electrical work is simple and inexpensive.
3) Since the radial suction force is always canceled, an extra load is not applied to the bearing, so that a sleeve bearing can be used and the cost is reduced.
4) Since the slider can be made to slide on the outer periphery of the fixed shaft, the bearing structure is simple and an inexpensive sleeve metal can be used, and since the slider is a cylindrical slider, the inertia is low and the responsiveness is improved.
5) Having a permanent magnet between the phases of the two-phase annular coil armature, and sliding the toothed magnetic cylindrical member on the fixed shaft enables a low-priced, high-thrust permanent magnet linear motor. Become.
6) An inexpensive brushless linear motor can be obtained by detecting the position and speed of the slider and switching the coil current at an optimal timing.
7) Very suitable for application to compressors and syringe pumps. In addition, it can be used as an optimal actuator for valve opening / closing, welding, soldering robots, etc.

1 is a cross-sectional view of an annular coil linear motor according to the present invention. FIG. 2 is a schematic front view of FIG. 1. FIG. 2 is an explanatory diagram of the operation principle of FIG. Sectional drawing of another annular coil-type linear motor of this invention. Sectional drawing of the electric compressor using the linear motor which concerns on this invention. (A) Side view of a conventional surface-facing linear motor. (B) The front view. Sectional drawing of the conventional permanent magnet type annular coil linear motor. Compressor sectional drawing of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Armature yoke 2 Annular coil 3 Non-magnetic material 4 Housing 5 Fixed shaft 6 Cylindrical moving element 7 Bearing,
21 Armature yoke 22 Annular coil 23 Permanent magnet 24 Magnetic tooth portion 25 Fixed shaft,
26 Housing 30 Stator 31 Mover 32 Fixed shaft 33 Housing 34 Piston 35 Cylinder 36 Intake duct 37 Exhaust duct 40 Armature yoke 41 Coil 42 Magnetic tooth portion 43 Tooth portion support portion 44 Bearing 45 Shaft 46 Frame 50 Wheel 51 Wheel 52 Coil 53 Disc 54 Hard sphere 55, 56 Piston 57 Cylinder

Claims (12)

  A relatively movable armature, a cylindrical member, and a linear stepping motor in which a shaft for holding the armature is concentric, and the armature is formed of an annular coil and a magnetic body so as to sandwich the annular coil A plurality of unit armatures having a pair of armature yokes provided on the same are arranged coaxially, and each of the armature yokes has annular magnetic teeth with alternating irregularities in the axial direction on the inner peripheral surface thereof. And a magnetic cylindrical member that is opposed to the inner peripheral surface of the armature via a small gap, and that has a cylindrical shape and annular magnetic teeth that are annular and uneven in the axial direction in the axial direction. An annular coil linear stepping motor characterized in that an armature and a cylindrical member or an integral of a cylindrical member and a shaft are relatively movable by energization of the coil.   2. The annular coil linear stepping according to claim 1, wherein the armature is integrated with a housing and a shaft to form a stator, and the cylindrical member is configured to be movable with the shaft as a guide. motor.   When the armature is composed of P unit armatures and the number of the annular magnetic teeth is plural and the arrangement pitch or the annular magnetic tooth pitch of the cylindrical member is τ, they are substantially the same, and the annular magnetic teeth facing each other 3. The annular coil according to claim 1, wherein when the magnetic poles of the teeth are opposed to each other in one phase, the other phase is configured to be at a position shifted by at least τ / P. Type linear stepping motor. However, P is an odd number of 3 or more.   4. An armature provided on the outside and a cylindrical member provided on the inside are replaced with a cylindrical member provided on the outside and an armature provided on the inside. Ring coil type linear stepping motor.   5. The structure according to claim 1, wherein when the number P of armatures is 3, three annular coils are configured to operate by star or delta connection three-terminal drive. The described annular coil linear stepping motor. An armature as a stator and a cylindrical member as a mover, and a linear stepping motor in which a fixed shaft for holding the armature is a concentric shape. The armature is formed of an annular coil and a magnetic body. Two unit armatures having a pair of armature yokes provided so as to be sandwiched between each other, the permanent magnets magnetized in the axial direction are sandwiched and arranged coaxially, and each armature yoke has its inner peripheral surface Have an annular magnetic tooth with alternating irregularities in the axial direction, and face the inner peripheral surface of the armature via a small gap, and have an annular magnetic tooth with annular alternating irregularities in the axial direction on the outer circumferential surface. An annular body characterized in that the inner peripheral portion of the cylindrical member is fitted to the outer peripheral portion of the fixed shaft and is movable by energization of the annular coil of the armature. Coil type linear stepping motor.   The annular coil permanent magnet type linear stepping motor according to claim 1 is provided, and is configured to excite a next phase at a predetermined timing by detecting a position and a moving speed of the moving element. An annular coil type linear brushless motor characterized by that.   A syringe pump drive device characterized in that the annular coil linear motor according to claim 1 is used as a drive source. The annular coil linear motor according to any one of claims 1 to 7 or the cylindrical member opposed to the armature inner peripheral surface via a small gap in claims 1 to 5 as a cylindrical permanent magnet, A linear cylinder provided with a mover cylindrical member in which N poles and S poles are alternately magnetized on the outer periphery of the cylindrical permanent magnet in place of the ring magnetic teeth so that the above-mentioned concave and convex annular magnetic teeth pitch is N poles and S poles. A cylinder type compressor driving device characterized by using a stepping motor and a linear brushless motor as driving sources. A cylinder-type compressor drive device, which is a compressor drive device that drives one cylinder with one linear motor, and in which one cycle of the linear motor performs intake and compression exhaust. A cylinder type compressor driving device comprising a plurality of compressor driving devices for driving one cylinder with one linear motor, wherein the driving cycle is changed between the plurality of devices. A cylinder type compressor driving device characterized in that a compressor driving device for driving one cylinder with one linear motor changes the output of the compressor by changing the stroke of the linear motor.