KR20000028607A - Sr motor, sr linear motor and load transfer equipment - Google Patents

Abstract

PURPOSE: An SR(Switched Reluctance) motor in which a torque and a propulsive force become big in the same current density compared to the existing SR motor, an SR linear motor in which the propulsive force becomes big in the same current density and a generation propulsive force is 0 without a point and a device for moving and loading cargo prepared with the SR linear motor are provided. CONSTITUTION: A stator(16) is fixed in the center of a fixing fork as a first side of an SR linear motor(15), and the number of a pole of the stator of which each pole is formed at the same pitch is 3n. Herein, all coils are wound up in the same direction in each pole, and each coil is made up to be a 3-phase. In addition, a u-phase current is supplied to the coil(18) corresponding to the poles(17a,17d), a v-phase current to the coil corresponding to the poles(17b,17e), and a w-phase current to the coil corresponding to the poles(17c,17f) through a driving circuit. In addition, an operator(19) is formed with a protrusion unit(19) at the same pitch arranged to face the poles. Thereby, the linear motor is miniaturized.

Description

Sr motor, sr linear motor, and load moving device {sr motor, sr linear motor and load transfer equipment}

The present invention relates to a load moving device having a switched reluctance motor (hereinafter referred to as SR motor), a switched reluctance linear motor (hereinafter referred to as SR linear motor) and an SR linear motor.

Stacker cranes, which have been used as unloading machines in automatic warehouses, are equipped with a load moving device (slide fork). The load moving device is provided with a fixed fork (fixing part) and a plurality of movable forks (movable parts) which can be pulled out horizontally with respect to the fixed fork, and the load is loaded on the uppermost movable fork. Each movable fork is configured to expand and contract in conjunction with driving of a drive device provided in the fixed fork. As a fork device of this kind, there is disclosed a built-in linear motor as an outgoing driving part of a movable fork (for example, Japanese Patent Laid-Open No. 57-77199). Although not specified in the publication, it is assumed that a linear induction motor has been used as the linear motor.

In addition, various linear motors corresponding to conventional rotating machines are known, and some of them have been implemented. Among the linear motors, linear DC motors, linear pulse motors and linear induction motors have been put into practical use. Among these, linear induction motors are used in relatively large devices such as pallet conveying devices.

Since the linear induction motor has a phenomenon called end effect, there is a problem that propulsion is lowered in high speed region. As a result, there was a problem that the apparatus is enlarged in order to obtain a large propulsion force. In addition, the linear pulse motor is characterized in that the movable part moves forward in synchronization with the input pulse signal, so that the open loop control is possible and the displacement error does not accumulate. However, in order to move smoothly, a magnetic pole set at a predetermined pitch is used. The distance between teeth (protrusions) needs to be narrowed (about 1 to 2 mm), and in devices that require a large moving distance, such as a load moving device, there is a problem that it takes time to process the coil and the teeth or wind the coil. .

In addition, it is conceivable to use the magnetic force of the permanent magnet to increase the propulsion force.However, when a linear motor using the permanent magnet is used for the load moving device, a magnetic bolt or nut of iron such as iron, which is left in the storage shelf, is adsorbed to the magnet. It may cause a malfunction.

The inventors of the present invention have studied SR linear motors, which have almost never been studied practically, and have produced a SR linear motor in which the winding result method applied to a conventional rotary SR motor using magnetic inductance as its operation principle is developed as it is. In addition, the driving force applied to the conventional rotary SR motor was applied to measure the generated propulsion force. As the drive circuit system, one-phase excitation drive (unipolar circuit) and two-phase excitation drive (bipolar circuit) were performed.

As a result, it was found that the average propulsion power of several times can be obtained compared to the conventional linear induction motor, and the average propulsion power of the 1-phase excitation drive is larger than the 2-phase excitation drive. However, in the case of the 1-phase excitation drive, there is a problem that the driving force is generated to zero and the fluctuation of the driving force is large. Moreover, in the case of 1-phase excitation drive, there also exists a problem that a dedicated drive circuit is needed. On the other hand, in the case of two-phase excitation driving, there is no point at which the generated propulsion force becomes zero and the fluctuation of the propulsion force is small. However, the driving force is not necessarily satisfactory. In addition, a large torque is required at the same current density in the rotary SR motor.

The present invention has been made in view of the above problems, and a first object is to provide an SR motor whose torque or propulsion force is increased at the same current density as compared with a conventional SR motor. Moreover, a 2nd object is to provide the SR linear motor which does not have the point which becomes large and the driving force becomes zero at the same current density compared with the SR linear motor which developed the rotating SR motor as it was planarly spread. In addition, a third object is to provide a load moving device including the SR linear motor.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic side view of the SR linear motor of 1st Embodiment.

2 is a cross-sectional view of the fork device of the first embodiment.

3 is a schematic perspective view of the fork device.

4 is a graph showing a current pattern of one-phase excitation driving.

5 is a graph showing a current pattern of two-phase excitation driving.

6 is a graph illustrating a current pattern of sinusoidal driving.

Fig. 7 is a magnetic flux diagram of two-phase excitation driving when mutual inductance is used together.

Fig. 8 is a magnetic flux diagram of sinusoidal driving when mutual inductance is used together.

9 is a graph showing propulsion characteristics when using mutual inductance together.

Fig. 10 is a magnetic flux diagram of one-phase excitation driving when using magnetic inductance.

Fig. 11 is a magnetic flux diagram of two-phase excitation driving when using magnetic inductance.

Fig. 12 is a magnetic flux diagram of sinusoidal driving when using magnetic inductance.

Fig. 13 is a graph showing propulsion characteristics when using magnetic inductance.

14 is a graph showing the current pattern of the 1-2 phase excitation drive.

15 is a graph showing the propulsion characteristics of the 1-2 phase excitation drive and the sinusoidal drive.

Fig. 16 is a magnetic flux diagram of a 1-2 phase excitation drive when using magnetic inductance.

It is a schematic diagram of the SR motor of 2nd Embodiment, and FIG. 17B is a schematic diagram of the conventional SR motor.

18A is a magnetic flux line diagram of sinusoidal wave driving of the SR motor of the second embodiment, and FIG. 18B is a magnetic flux line diagram of sinusoidal wave driving of the conventional SR motor.

19 is a graph showing torque characteristics of a rotary SR motor.

* Brief description of the main parts of the drawing

1: Fork device as load moving device 2: Fixed fork as fixed part

3: Second fork as movable part 4: Third fork as movable part

5: Up fork as movable part 15: SR linear motor

16, 36 stator 17a-17f, 36a-36f pole

18: coil 19: mover

19a: projection 35: SR motor

38: rotor as movable portion 38a: teeth as protrusion

Means to solve the problem

In order to achieve the first object, the invention according to claim 1 uses magnetic inductance and mutual inductance together as an operation principle.

In the invention according to claim 2, in the invention according to claim 1, the ratio of the number of poles of the stator to the number of protrusions of the movable parts of the parts corresponding to the stator is set to 3: 4, and the number of poles of the stator is 3n (n is The coils of each pole are all wound in the same direction.

In the invention according to claim 3, in the invention according to claim 1 or 2, the poles of the stator are formed at equal pitches.

In the invention according to claim 4, in the invention according to claim 1 or 2, the driving method is bipolar sine wave driving.

In order to achieve the second object, in the invention described in claim 5, the SR motor is an SR linear motor in the invention according to claim 1 or 2.

In addition, the invention described in claim 6 uses magnetic inductance as the operation principle and sets the driving method to the unipolar 1-2 phase excitation drive.

In order to achieve the 3rd object, the invention of Claim 7 or 8 is equipped with one fixed part and several movable parts which can be taken out horizontally in order with respect to this fixed part, The said fixed part and the movable part At least one of the SR linear motors according to claim 5 or 6 is incorporated as an outgoing driving part of the movable portion.

According to the invention according to claim 1, the magnetic inductance and mutual inductance are used together as an operation principle, and when a current flows through the coil of the stator, the mover is always moved by a magnetic force and moves in a predetermined direction.

According to the invention described in claim 2, in the invention according to claim 1, the ratio of the number of poles of the stator to the number of protrusions of the movable parts of the parts corresponding to the stator is set to 3: 4, so that the mover moves smoothly. In addition, the coils of the poles are all wound in the same direction, thereby simplifying the coil winding operation.

In the invention according to claim 3, in the invention according to claim 1 or 2, the poles of the stator are formed at the same pitch so that the mover moves smoothly.

In the invention according to claim 4, in the invention according to claim 1 or 2, since the driving method is a bipolar sine wave drive, a general-purpose inverter can be used as a driving circuit.

In the invention according to claim 5, in the invention according to claim 1 or 2, since the SR motor is an SR linear motor, the mover moves linearly.

In the invention according to claim 6, magnetic inductance is used as an operating principle. As a driving method, a unipolar 1-2 phase excitation drive is used.

As for the load moving device of the invention of Claim 7 or 8, the SR linear motor of Claim 5 or 6 is used as the movable part outgoing actuation drive part in at least 1 of a fixed part and a movable part, respectively. .

Embodiment of the invention

(1st embodiment)

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment which actualized this invention is described according to FIGS.

First, a configuration of a fork device as a load moving device will be described. As shown in Figs. 2 and 3, the fork device 1 has a second fork 3 and a third fork 4 as a plurality of movable parts which can be pulled out sequentially with respect to the fixed fork 2 and the fixed fork 2 as the fixed part. ) And up fork 5.

As shown in FIG. 2, a pair of rails 6 extending in the longitudinal direction are fixed to the bottom surface of the second fork 3, and each rail 6 is fixed to the longitudinal center portion of the fixed fork 2. It is supported to be movable along the longitudinal direction of the fixed fork 2 through the linear guide block 7. A pair of support rollers 8 (shown in FIG. 3) are provided at both ends of the fixed fork 2, respectively. The second fork 3 is movable in the longitudinal direction with respect to the fixed fork 2 in the state supported by the linear guide block 7 and the support roller 8.

Similarly, a pair of rails 9 are fixed to the bottom surface of the third fork 4, and the linear guide block 10 and the support roller 11 are provided on the second fork 3. The third fork 4 is movable in the longitudinal direction with respect to the second fork 3 in a state supported by the linear guide block 10 and the support roller 11. In addition, the up fork 5 is also supported by the linear guide block 13 fixed to the third fork 4 via the rail 12 fixed to the bottom surface. The linear guide block 13 and the support roller 14 provided at both ends of the third fork 4 are supported in the longitudinal direction with respect to the third fork 4.

The stator 16 as the primary side of the SR linear motor 15 is fixed to the center portion of the fixed fork 2. As shown in FIG. 1, the number of poles is 3n (n = 2 in this embodiment), and each pole 17a-17f is formed in equal pitch. In each of the poles 17a to 17f, a large amount of the coils 18 are wound in the same direction. Each coil 18 is configured to be in three phases, u phase for the coil 18 corresponding to the poles 17a, 17d, v phase for the coil 18 corresponding to the poles 17b, 17e, 17c, The current on w is supplied to the coil 18 corresponding to 17f) through a driving circuit not shown, respectively. As the drive circuit, a general-purpose three-phase inverter is used and controlled through a control device not shown. The controller is configured to control the inverter to drive the sine wave of the SR linear motor 15.

The movable element 19 as the secondary side of the SR linear motor 15 is fixed to the bottom surface of the second fork 3 by a bolt 20 in a groove 3a formed so as to extend over almost the entire length thereof in the longitudinal direction. . The movable part 19 is provided with the projection part 19a by equal pitch, and the projection part 19a is arrange | positioned so that it may oppose the poles 17a-17f. The ratio of the number of poles 17a to 17f of the stator 16 and the number of the protruding portions 19a of the mover 19 of the portion corresponding to the stator 16 is set to 3: 4. The poles 17a to 17f and the protrusions 19a are formed to have almost the same width. When the current is supplied to each of the coils 18, the second fork 3 is moved in the longitudinal direction thereof.

The rack 21 is fixed in the groove formed in the upper surface of the one side (right side of FIG. 2) of the fixing fork 2. As shown in FIG. The rack 22 is fixed in the groove formed in the lower surface of the third fork 4. The second fork 3 is supported such that the rotating shaft 25, on which the pinions 23 and 24 meshed with the racks 21 and 22, respectively, are fixed to both ends so as to rotate through the bearing 26. Pinions 23 and 24 are formed in the same manner.

The rack 27 is fixed in the groove formed in the upper surface of the other side (left side of FIG. 2) of the second fork 3. As shown in FIG. The rack 28 is fixed in the groove formed in the lower surface of the other side of the up fork 5. The third fork 4 is supported such that a rotation shaft 31 having pinions 29 and 30 meshed with the racks 27 and 28, respectively, can be rotated through the bearing 26. The pinions 29 and 30 are formed with the same number of teeth with the same diameter as the pinions 23 and 24. Therefore, when the second fork 3 moves, the third fork 4 and the up fork 5 are driven by the action of the racks 21, 22, 27, 28 and the pinions 23, 24, 29, 30. Are moved the same for.

Sensors S1 and S2 for detecting in which direction the second fork 3 moves in the center reference position are provided in the central portion of the side surface of the fixed fork 2. On the bottom surface of the second fork 3, a band-shaped detecting member 32 (shown in FIG. 2) is positioned at a position that can be opposed to the sensor S1 in a state extending from the right side to the almost right end of the center of FIG. It is fixed. The sensor S1 is provided at a position capable of detecting the detected member 32 in the state where the second fork 3 has moved to the left side of FIG. 3 from the reference position and the reference position. On the bottom surface of the second fork 3, a band-like detecting member 33 (shown in FIG. 2) can be opposed to the sensor S2 in a state in which it extends from the left side to the almost left end from the center of FIG. It is fixed at. The sensor S2 is provided at a position capable of detecting the detected member 33 in the state where the second fork 3 has moved to the right side of FIG. 3 from the reference position and the reference position.

The detection signals of the sensors S1 and S2 are input to a control device not shown, and the control device moves in the direction of Fig. 3 with respect to the reference position or the second fork 3 or the like based on the signal. Recognize that you are doing When the ON signal is output from both sensors S1 and S2, the controller determines that the second fork 3 and the like are in the reference position. Also, if the ON signal is output only from the sensor S1, it is determined that the second fork 3 and the like have moved to the left side of FIG. 3 with respect to the reference position, and if the ON signal is output only from the sensor S2, the second fork 3, etc. It is determined that the reference position has moved to the right side of FIG. 3.

As shown in FIG. 2, the detected part 34 is fixed to the bottom surface of the second fork 3 inside the detected member 33. The detection part 34 is provided in the left and right both ends of the bottom surface of the 2nd fork 3 of FIG. 3, and is fixed so that the front-end may protrude into the groove 2a formed in the fixed fork 2. As shown in FIG. The fixed fork 2 is provided with a sensor S3 capable of detecting the detection unit 34 at the center and at both left and right ends of FIG. 3, respectively. A plurality of sensors S3 are provided, respectively, and the control device is configured to output the deceleration command and the stop command of the SR linear motor 15 based on the detection signal from each sensor S3.

Next, the operation of the fork device 1 configured as described above will be described. The fork device 1 is equipped with, for example, a cut clay of an automatic warehouse.

When current is sequentially supplied to the coil 18 of the stator 16 of the SR linear motor 15 in the state where each fork 3 to 5 is arranged at the reference position, the currents 17a to 17f and corresponding poles are supplied. The amount of magnetic flux passing through the protrusion 19a changes in order. Then, the suction force acting on the protruding portion 19a of the movable element 19 changes in order, and the second fork 3 on which the movable element 19 is fixed moves in a predetermined direction. In Fig. 1, the protrusion 19a located on the left side with respect to the poles 17a to 17f and the magnetic flux passing through the pole corresponding to the protrusion 19a impart the driving force to the mover 19 in the right direction, The magnetic flux passing through the projection 19a located at the pole and the pole corresponding to the projection 19a gives the movable element 19 a propulsion force in the left direction. Therefore, when the poles 17a to 17f are excited in order so that the amount of magnetic flux imparting the propulsion force in the left direction is increased, the mover 19 moves in the left direction and the magnetic flux imparting the propulsion force in the right direction is increased. When each pole 17a-17f is excited in order so that quantity may increase, the mover 19 will move to a right direction.

As the second fork 3 moves, the rotating shaft 25 supported by the second fork 3 moves integrally, and the pinion 23 meshed with the rack 21 rotates integrally with the rotating shaft 25. And the pinion 24 fixed to the rotating shaft 25 rotates integrally, and the rack 22 which meshes with the pinion 24 is moved by the same amount as the movement amount with respect to the fixed fork 2 of the second fork 3. Accordingly, the third fork 4 to which the rack 22 is fixed is moved relative to the second fork 3 by the same amount.

In addition, as the third fork 4 moves, the rotary shaft 31 supported by the third fork 4 moves integrally, and the pinion 29 meshing with the rack 27 rotates integrally with the rotary shaft 31. And the pinion 30 fixed to the rotating shaft 31 rotates integrally and the rack 28 which meshes with the pinion 30 is moved by the same amount as the movement amount with respect to the second fork 3 of the third fork 4. Thus, the up fork 5 to which the rack 28 is fixed is moved relative to the third fork 4 in the same amount. In other words, the upfork 5 is moved by a distance three times the distance at which the second fork 3 is moved by the drive of the SR linear motor 15.

The control device recognizes the position of the second fork 3 based on the output signals of the sensors S1 and S2 and recognizes the deceleration position and the stop position based on the output signal of the sensor S3. The deceleration command is output from the deceleration position and the stop command is output from the stop position.

Subsequently, the SR linear motor 15 using magnetic inductance and mutual inductance as a principle of operation and the winding connection method applied to a conventional rotary SR motor are flat-deployed as it is, and the FEM (SR) for the SR linear motor using magnetic inductance is used as an operation principle. Explain the results of comparing the average propulsion force using the finite element method.

As an analytical model, the number of poles of the stator 16 shown in FIG. 1 is 6 and the ratio of the number of poles of the stator 16 and the number of protrusions 19a of the mover 19 is 3: 4. Magnetic inductance and mutual inductance are used in combination with the principle of operation, and the winding type in the coil direction shown in Fig. 1 is implemented by two-phase excitation driving and sinusoidal driving. In addition, as a comparative example, the magnetic inductance was used as the operation principle, which was performed by one-phase excitation drive, two-phase excitation drive, and sine wave drive. In the case of one-phase excitation drive and two-phase excitation drive and sinusoidal drive, a large amount of coils are wound similarly, but the winding direction is different. The winding direction was shown by the code | symbol in FIGS. 10-12.

The current density was constant at 6.175 × 10 ⁶ AT / m 2 for each current waveform. In FIG. 4, current patterns of u-phase, v-phase, and w-phase are shown in FIG. The current patterns of the phases, v phases, and w phases are shown.

In Fig. 7, the magnetic flux diagram when the two-phase excitation drive is carried out for the combination of the magnetic inductance and the mutual inductance is shown. In Fig. 8, the magnetic flux diagram is shown for the sine wave driving. Fig. 9 shows the results of the propulsion force characteristics when two-phase excitation drive and sine wave drive are performed. 7 and 8 illustrate the case where the mover 19 is moved in the right direction of the same drawing.

In FIG. 10, the magnetic flux diagram when the 1-phase excitation drive is performed for the use of the magnetic inductance, the magnetic flux diagram for the 2-phase excitation drive, and the magnetic flux diagram for the sinusoidal wave driving in FIG. 12, respectively. Indicates. Fig. 13 shows the results of the propulsion force characteristics when the 1-phase excitation drive, the 2-phase excitation drive, and the sine wave drive are performed. 10-12 illustrate the case where the movable element 19 is moved to the right direction of the same figure.

In the SR linear motor 15 using both magnetic inductance and mutual inductance, the average propulsion force is 160 N in the case of two-phase excitation driving and 230 N in the case of sine wave driving. On the other hand, in the SR linear motor using the magnetic inductance, the average propulsion force is 200 N for the 1-phase excitation drive, 156 N for the 2-phase excitation drive, and 154 N for the sinusoidal drive. That is, in the SR linear motor using magnetic inductance, the average driving force is almost the same in the case of two-phase excitation driving and the sine wave driving, and the average driving force increases by more than 20% in the case of one-phase excitation driving. It became. However, in the case of the 1-phase excitation drive, there is a problem that there is a point where the driving force is large, as shown in FIG.

On the other hand, in the SR linear motor 15 using both magnetic inductance and mutual inductance, the improvement of the average propulsion power was about 3% compared to the SR linear motor using magnetic inductance in the case of two-phase excitation driving. On the other hand, in the case of sinusoidal driving, the driving force is improved by more than 40% compared to the two-phase excitation driving. Also, compared with the case of single phase excitation driving of SR linear motor using magnetic inductance, the improvement was 15%. Therefore, it has been found that the average propulsion force is greatly improved by adopting the sinusoidal drive method in the SR linear motor 15 which uses both magnetic inductance and mutual inductance.

This can also be seen from the magnetic flux diagram of FIGS. 7, 8 and 10-12. For example, comparing FIG. 7 and FIG. 8, the amount of magnetic flux passing through the poles 17b and 17e on v is almost the same in FIGS. 7 and 8, but the amount of magnetic flux passing through the poles 17a and 17d on u is FIG. 7. There are many. In addition, the amount of magnetic flux passing through the poles 17c and 17f on w is large in Fig. 8, and the protrusions 19a and poles 17c and 17f located on the left side of Figs. 7 and 8 with respect to the poles 17c and 17f. The amount of magnetic flux passing through is also large. Accordingly, the driving force increases in FIG. 8, in which a large amount of magnetic flux is applied to the mover 19 in the right direction.

In the SR linear motor 15 which uses the magnetic inductance and the mutual inductance together, the amount of magnetic flux passing through the poles 17a to 17f is larger than that of the SR motor using the magnetic inductance. However, in the case of the two-phase excitation drive in the SR linear motor 15, as shown in Fig. 7, the ratio of the magnetic flux giving the reverse propulsion force increases as compared with the sinusoidal wave driving, as shown in Fig. 7, even if the total amount of the magnetic flux increases. The driving force did not increase. If the ratio of the magnetic flux which imparts the reverse propulsion force by changing the shape of the pole (for example, the width) or the shape (for example, the width) of the protrusion 19a, the propulsion force may increase.

In this embodiment, the following effects are obtained.

(1) Since the magnetic inductance and the mutual inductance are used together as the operating principle of the SR linear motor 15, the amount of magnetic flux passing through the poles 17a to 17f is increased compared to the SR linear motor using the magnetic inductance, thereby providing a large propulsion force. You can get it.

(2) The ratio of the number of poles 17a to 17f of the stator 16 and the number of protrusions 19a of the movable part 19 of the portion corresponding to the stator 16 is set to 3: 4 and the stator 16 The number of poles is 3 n (n is a natural number), and the coils 18 of each pole are all wound in the same direction. Therefore, a configuration in which magnetic inductance and mutual inductance are used together as a principle of operation can be easily formed, and a suction force by magnetism acting between the pole and the projection 19a effectively acts as the driving force of the movable element 19.

(3) Since the poles 17a to 17f and the protrusions 19a are formed to have substantially the same width, the ratio between the poles 17a to 17f and the number of the protrusions 19a is set to 3: 4, and The attraction force by magnetism acting between the projections 19a effectively acts as the driving force of the movable element 19.

(4) Since the poles 17a to 17f of the stator 16 are formed at the same pitch, the processing of the stator 16 becomes simpler and the control becomes simpler than the case where it is not the same pitch.

(5) Since the drive method is a bipolar sine wave drive, a general-purpose inverter can be used as the drive circuit, and the manufacturing cost can be reduced as compared with that of the unipolar one-phase excitation drive that requires a dedicated drive circuit.

(6) The same current compared to the SR linear motor in which the induction linear motor or the rotary SR motor of the same size is unfolded as it is, in order to use the SR linear motor 15 as an outgoing actuation drive part of the movable part of the fork device 1. The driving force increases in density. Therefore, when the size of the linear motor is the same, it is possible to carry a mobile load of heavy loads, and the linear motor can be miniaturized if the driving force required for the load of the load is the same.

(7) The propulsion force can be increased without using a permanent magnet, and when the SR linear motor 15 is used as a driving part of the fork device 1, it is possible to avoid the trouble caused by the adsorption of bolts or the like that are left on the shelves. Can be.

(2nd embodiment)

Next, 2nd Embodiment is described according to FIGS. 14-16. This embodiment differs greatly from the above embodiment in that the magnetic inductance is used as the operation principle of the SR linear motor and the driving method is the 1-2-phase excitation drive of the unipolar. The coil 18 is wound intensively, and the winding direction is set in the same manner as the SR linear motor of the one-phase excitation drive.

Under the same conditions as in the above embodiment, the SR linear motor 15 using the magnetic inductance and the mutual inductance using the FEM (finite element method) was compared with the case of sine wave driving. FIG. 14 shows the current patterns of u, v, and w phases in the case of 1-2 phase excitation drive, and FIG. 16 shows the magnetic flux diagram in the case of 1-2 phase excitation drive. Fig. 15 shows propulsion characteristics in the case of 1-2 phase excitation driving when using magnetic inductance and propulsion characteristics in the case of sine wave driving when mutual inductance is used.

In the SR linear motor 15 using mutual inductance, the average propulsion force was 230 N in the case of sinusoidal driving, and the average propulsion force was 225 N in the SR linear motor of 1-2 phase excitation driving while using the magnetic inductance. In the SR linear motor using the magnetic inductance as the comparative example in the first embodiment, the average propulsion force was improved by 10% or more as compared to the one-phase excitation drive with the maximum average propulsion force. In addition, the fluctuation of the propulsion force was small compared with the case of sine wave drive which used mutual inductance together. In other words, if the 1-2 phase excitation drive is used instead of the 1 phase excitation drive, the average driving force is improved by 10% or more compared with the 1 phase excitation structure, and the driving force is small and the driving force is small, unlike the case of the 1 phase excitation drive. There is no point at zero.

Therefore, in this embodiment, it has the following effects other than having the effect of (3) and (4) of 1st Embodiment.

(8) In the SR linear motor using the self-inductance as a principle, the winding connection method applied to the rotary SR motor is used as a flat surface, and the driving method replaces the 1-2 phase excitation drive. In addition, it is possible to obtain an SR linear motor having no point at which the driving force is zero.

(Third embodiment)

Next, 3rd Embodiment is described according to FIGS. 17-19. In this embodiment, the point of application to the rotary SR motor which uses magnetic inductance and mutual inductance as an operation principle differs greatly from the above two embodiments.

17A is a schematic diagram of an SR motor 35 incorporating the present invention. The SR motor 35 is provided with the cylindrical stator 36 which has 3n (n is natural number, and in this embodiment, n = 2) poles 36a-36f. Each of the poles 36a to 36f is set at equal intervals (equal pitch), and a large amount is wound around each of the poles 36a to 36f in the same direction. In addition, P is a neutral point in FIG. 17A. Each coil 37 is configured to be in three phases, u phase for the coil 37 corresponding to the poles 36a, 36d, v phase for the coil 37 corresponding to the poles 36b, 36e, 36c, The current on w is supplied to the coil 37 corresponding to 36f) through a driving circuit not shown, respectively. In the rotor 38 as the movable element, eight teeth 38a are formed at equal intervals (equal pitch).

17B shows a conventional SR motor 39. The SR motor 39 has a winding method and a wiring method of the coil 37 different from the SR motor of the embodiment, and the other configurations are the same. Each coil 37 of each pole 36a-36f is wound so that the winding direction may alternately reverse.

The characteristics of the SR motors 35 and 39 constructed as described above were compared using the FEM (finite element method). FIG. 18A shows a magnetic flux diagram when sine wave driving is performed for an SR motor that uses magnetic inductance and mutual inductance as a principle of operation, that is, the SR motor 35 shown in FIG. 17A. Fig. 18B shows a magnetic flux diagram when sinusoidal wave driving is performed at the same current density with respect to a conventional SR motor using magnetic inductance as an operation principle, that is, the SR motor 39 shown in Fig. 17B. 19 is a graph which shows the relationship (torque characteristic) of the mechanical angle and torque of SR motor when the polarization drive of each SR motor 35 and 39 is performed. 18A and 18B both show the case where the rotor 38 is rotated in the counterclockwise direction (left direction) of each figure, and only three poles (half) are shown, respectively.

18A corresponds to a state where the current density supplied to the poles 36b and 36e on v is maximum, and FIG. 18B corresponds to a state where the current density supplied to the poles 36a and 36d on u is maximum. . Comparing the amount of magnetic flux passing through the pole 36b and the corresponding tooth 38a of FIG. 18A with the amount of magnetic flux passing through the pole 36a and the corresponding tooth 38a of FIG. 18B, passing through the pole 36b There are many. In addition, the amount of magnetic flux that applies the suction force of the left rotation to the rotor 38 while passing through the pole 36a and the corresponding tooth 38a on u in FIG. 18A and the pole 36b and the corresponding tooth on V in FIG. 18B ( Comparing the amount of magnetic flux which applies the suction force of the left rotation to the rotor 38 while passing through 38a), it passes through the pole 36a of u phase in many cases. Therefore, the torque of the SR motor 35 which uses magnetic inductance and mutual inductance together as an operation principle in a rotary SR motor becomes large.

This can be confirmed also in the graph which shows the torque characteristic of the SR motor shown in FIG. The average torque of the SR motor 35 is improved by about 5% over the conventional SR motor 39. That is, even in the rotary SR motor, in the configuration in which the magnetic inductance and the mutual inductance are used together as the operation principle, the torque is improved as compared with the conventional SR motor using the magnetic inductance as the operation principle.

In addition, embodiment is not limited to the above, For example, you may specify as follows.

The number of poles of the stator 16 is not limited to six, but may be three, three or more than three triples. In other words, the number of poles of the stator 16 may be 3 n (n is a natural number). In this case, it becomes easy to use a general purpose three-phase inverter as a drive circuit.

The widths of the poles 17a to 17f and the projections 19a do not necessarily have to be formed substantially the same, and the pitches of the poles and the projections 19a are the same and may be different in width.

A plurality of small teeth may be formed at the tips of the poles 17a to 17f and the protrusions 19a.

The fork device 1 is not limited to four stages but may be three stages.

When the SR linear motor 15 is used as the driving portion of the fork device 1, the second fork 3 and the third fork are replaced instead of the SR linear motor 15 between the fixed fork 2 and the second fork 3. You may arrange | position between (4) or between the 3rd fork 4 and the upfork 5. However, in consideration of the ease of wiring winding to the coil 18, it is preferable to provide the stator 16 in the fixed fork 2.

The SR linear motor 15 may be provided between each movable fork, and the drive mechanism of the movable fork by pinion and rack may be removed. In this case, oscillation by the engagement of the rack and pinion is eliminated, and thus it is suitable for use in a clean room.

Instead of equipping the stacker crane with the forklift device 1, the self-propelled vehicle may be equipped. In addition, the fork device 1 may be used as the stationary mobile loading device.

It is good also as a structure which makes the primary side of SR linear motor 15 the movable side, and the secondary side the stator. In this configuration, by moving the stator along the rail for guiding the movable body and attaching the movable body to the movable body, the movable body can be moved long distance to the SR linear motor.

About invention (technical thought) other than description of a claim which can be grasped by the said embodiment, it describes with the result below.

(1) The load moving device according to claim 7 or 8, wherein the stator of the SR linear motor is installed on the stator and is installed on the movable part facing the mover. Entry and exit movements are made at the drive mechanism. In this case, the winding of the wire to the load moving device is simplified.

As described in detail above, according to the invention of Claims 1 to 6, the torque or propulsion force is increased at the same current density as compared with the conventional SR motor.

According to the invention as set forth in claim 2, it is possible to easily form a constitution in which both magnetic inductance and mutual inductance are used as the operation principle, and the suction force by the magnet acting between the pole and the protrusion effectively acts as the driving force of the mover.

According to the invention as set forth in claim 3, the processing of the stator 16 becomes simpler and the control becomes simpler than in the case of making the pitch uneven.

According to the invention of claim 4, a general-purpose inverter can be used as a driving circuit, and manufacturing costs can be reduced as compared with unipolar single-phase excitation driving requiring a dedicated driving circuit.

According to the invention as claimed in claim 5, an SR linear motor can be obtained in which the propulsion force is increased at the same current density and the generation propagation force is zero compared to the SR linear motor in which the rotary SR motor is flat-deployed as it is.

According to the invention according to claim 6, the propulsion force is increased at the same current density and the generated propulsion force is 0 at the same current density, compared to the case where the SR linear motor in which the rotary SR motor is flat-deployed as it is in the 1-phase excitation drive, 2-phase excitation drive, or sinusoidal drive It is possible to obtain an SR linear motor having no point.

According to the invention according to claim 7 or 8, if the linear motor is the same size, the heavy load can be loaded and the linear motor can be downsized if the driving force required for the load is identical.

Claims (8)

SR motor using magnetic inductance and mutual inductance as operation principle. The ratio of the number of poles of the stators 16 and 36 to the number of protrusions 19a and 38a of the movable parts 19 and 38 of the portions corresponding to the stators is set to 3: 4, and the stator SR motor with 3n poles (n is a natural number) and coils 18 and 37 of each pole are all wound in the same direction. The SR motor according to claim 1 or 2, wherein the poles of the stator are formed at equal pitches. The SR motor according to claim 1 or 2, wherein the driving method is bipolar sinusoidal drive. The SR motor of claim 1 or 2, wherein the SR motor is an SR linear motor. SR linear motor using magnetic inductance as the principle of operation and driving method by unipolar 1-2 phase excitation drive. One fixing portion 2 and a plurality of movable portions 3, 4 and 5 that can be pulled out horizontally in order with respect to the fixing portion, and the fixing portions 2 and the movable portions 3, 4 and 5 A load moving device in which at least one of the SR motors according to claim 5 is incorporated as an outgoing actuation driving part of the movable part. One fixing portion 2 and a plurality of movable portions 3, 4 and 5 that can be pulled out horizontally in order with respect to the fixing portion, and the fixing portions 2 and the movable portions 3, 4 and 5 A load moving device in which at least one of the SR linear motors according to claim 6 is incorporated as an outgoing driving part of the movable part.