JP7360296B2 - Cylindrical linear motor - Google Patents

Description

The present invention relates to a cylindrical linear motor .

A cylindrical linear motor, for example, has a cylindrical core that has a plurality of teeth arranged in the axial direction on its outer periphery, and an armature that has U-phase, V-phase, and W-phase windings that are installed in slots between the teeth. and a stator consisting of a cylindrical yoke provided on the outer periphery of the armature and a plurality of permanent magnets attached to the inner periphery of the base so that south poles and north poles are arranged alternately in the axial direction. There is something.

In the cylindrical linear motor configured in this way, when the U-phase, V-phase, and W-phase windings of the armature are appropriately energized, the armature is attracted to the permanent magnet and the armature acts as a mover against the stator. driven in the axial direction.

In such a cylindrical linear motor, a core including a cylindrical yoke and annular teeth provided on the yoke is formed by a plurality of core segments divided in the axial direction for each tooth, and the windings are sandwiched between the core segments. In some cases, the armature is formed by stacking the core segments.

For example, in a cylindrical linear motor with an armature made up of stacked core segments, where the armature is arranged around the outer periphery of the field, the windings in the armature are arranged in U-phase, V-phase, and W-phase. Therefore, a large notch is provided from the yoke of the core to the tooth, and a slit is provided on the side of the tooth that leads from the tip of the tooth to the notch, and the crossover wire that connects the windings is drawn out of the core and connected (for example, , see Patent Document 1).

Japanese Patent Application Publication No. 2001-286122

In the cylindrical linear motor, large notches are formed in the yoke and teeth in the core, so magnetic saturation tends to occur, making it difficult to improve thrust.

Therefore, an object of the present invention is to provide a cylindrical linear motor that can improve thrust.

To achieve the above object, the cylindrical linear motor of the present invention includes an armature having a cylindrical core, a winding installed in a slot provided on the outer periphery of the core, and an armature having a cylindrical shape and an inner The core includes a cylindrical yoke and a magnetic field in which an armature is movably inserted in the axial direction and N and S poles are alternately arranged in the axial direction. It has a plurality of teeth arranged side by side, and a slit that is formed from the outer peripheral end of the tooth to the yoke, passes through the tooth in the axial direction, and into which the lead wire of the winding wire is inserted.

In a cylindrical linear motor configured in this way, the cross-sectional area of the slits provided in the yoke and teeth in the core is only large enough to allow insertion of the lead wire, so the cross-sectional area of the magnetic path in the core is significantly reduced. There is nothing to do. Therefore, magnetic saturation is less likely to occur in the core. Furthermore, since the lead wires that connect the windings are housed in the slits of the core and stored inside the windings, there is no need to arrange the lead wires between the core and the field. The radial distance between the two can be shortened.

Further, the core of the cylindrical linear motor may be formed by stacking a plurality of annular core segments divided in the axial direction so that each core segment has one tooth. According to the cylindrical linear motor configured in this way, the windings can be easily attached to the core and the windings can be connected, and the cylindrical linear motor can be manufactured easily.

Furthermore, the core division body in the cylindrical linear motor has three holes arranged at 120 degree intervals on the same circumference of the part corresponding to the yoke to accommodate the lead wires, and has an annular shape constituting one end of the core. It has a first core division body, and a plurality of second core division bodies each having two holes corresponding to a slit and a yoke and accommodating the lead wires on the same circumference passing through the slit. The slit and two holes in the two-core divided body may be arranged at 120 degree intervals on the same circumference. According to the cylindrical linear motor configured in this manner, the lead wires of the windings of each phase can be accommodated individually in the slits and holes, and the windings of each phase can be well insulated. In addition, according to the cylindrical linear motor configured in this way, the slits can be evenly arranged in the circumferential direction throughout the core with a phase difference of 120 degrees, so that the core can exert a large attraction force that causes eccentricity in the radial direction from the field. This allows the cylindrical linear motor to extend and retract smoothly without causing a decrease in thrust.

Further, the core division body in the cylindrical linear motor is a part corresponding to a yoke, and has three holes on the same circumference passing through the slit, and the slit and the three holes are arranged at 90 degrees on the same circumference. Two of the three holes may be used as holes for accommodating lead wires, and keys may be inserted into the remaining holes. According to the cylindrical linear motor configured in this way, the core division body can be easily positioned by inserting a key into one of the three holes, making the core manufacturing work very easy. Since the wires can be housed in different slits and holes, the windings of each phase can be well insulated.

Furthermore, the core division body in the cylindrical linear motor is an annular first core division body that has six holes arranged at 60 degree intervals on the same circumference of a portion corresponding to the yoke and constitutes one end of the core. and a plurality of second core division bodies each having a slit and five holes on the same circumference passing through the slit, which correspond to the slit and the yoke, and the slit and the five holes in the second core division body are , are arranged at 60 degree intervals on the same circumference, and the lead wires may be accommodated in the three holes of the first core division body and the slit and two holes of the second core division body. According to the cylindrical linear motor configured in this way, the slits can be arranged evenly throughout the core with a phase difference of 120 degrees in the circumferential direction, so the core is less susceptible to large attraction forces that make it eccentric in the radial direction from the field. Therefore, the cylindrical linear motor can smoothly expand and contract, and there is no reduction in thrust. In addition, the hole where the lead wire is not accommodated can be used as an air vent, so when the cylindrical linear motor expands and contracts, the pressure increases when the chambers on both sides of the armature in the axial direction of the cylindrical linear motor are compressed. Since the expansion and contraction of the cylindrical linear motor is not hindered, in this respect as well, the cylindrical linear motor can be smoothly expanded and contracted without causing a decrease in thrust force. Further, according to the cylindrical linear motor configured in this way, the key is inserted into one of the three axial holes formed by the three holes not connected to the slit, and the first core segment and the second core are separated. Since the divided bodies can be easily positioned, the core manufacturing work becomes very easy.

Further, the cylindrical linear motor may include a key that is inserted into one of the holes that communicate with each other in the stacked state of the core divided bodies and is not connected to the slit to position the core divided bodies in the circumferential direction. According to the cylindrical linear motor configured in this way, separation of the core segments after core assembly is prevented.

Furthermore, the slit in the core of a cylindrical linear motor may communicate with the inner periphery of the yoke, and when a cylindrical linear motor is configured in this way, the lead wires can be placed on the inner periphery of the core. It becomes easier to insulate the lead wires connected to the phase windings.

According to the cylindrical linear motor of the present invention, thrust can be improved.

FIG. 2 is a longitudinal cross-sectional view of a cylindrical linear motor in one embodiment. FIG. 2 is an enlarged vertical cross-sectional view of the core of the cylindrical linear motor according to one embodiment. It is a top view of the core of the cylindrical linear motor of one embodiment. It is a longitudinal cross-sectional view of the cylindrical linear motor in the first modification of one embodiment. It is a figure explaining the process of assembling the core of the cylindrical linear motor in the first modification of one embodiment. It is a longitudinal cross-sectional view of the cylindrical linear motor in the second modification of one embodiment. (A) is a perspective view of a core division body corresponding to one end of the core of a cylindrical linear motor in a second modification of the embodiment. (B) is a perspective view of a core division body corresponding to other than one end of the core of the cylindrical linear motor in a second modification of the embodiment. It is a top view of the core of the cylindrical linear motor in the second modification of one embodiment. It is a figure explaining the process of laminating the core division body of the cylindrical linear motor in the second modification of one embodiment. (A) is a perspective view of a first core division body corresponding to one end of the core of a cylindrical linear motor in a third modification of the embodiment. (B) is a perspective view of a second core division body corresponding to other than one end of the core of the cylindrical linear motor in a third modification of the embodiment. It is a longitudinal cross-sectional view of the cylindrical linear motor in the fourth modification of one embodiment. (A) is a perspective view of a first core division body corresponding to one end of the core of a cylindrical linear motor in a fourth modification of the embodiment. (B) is a perspective view of a second core division body corresponding to other than one end of the core of the cylindrical linear motor in a fourth modification of the embodiment. It is a top view of the core of the cylindrical linear motor in the fourth modification of one embodiment.

The present invention will be described below based on the embodiments shown in the figures. As shown in FIG. 1, a cylindrical linear motor 1 in one embodiment includes an armature 2 having a cylindrical core 3 and a winding 5 installed in a slot 4 provided on the outer periphery of the core 3; The armature 2 is inserted into the magnetic field 6 so as to be movable in the axial direction, and the field 6 has N poles and S poles arranged alternately in the axial direction.

Each part of the cylindrical linear motor 1 will be described in detail below. The armature 2 includes a core 3 and a winding 5. The core 3 includes a cylindrical yoke 3a, a plurality of annular teeth 3b provided at intervals in the axial direction on the outer circumference of the yoke 3a, a plurality of slots 4 provided between the teeth 3b, and teeth 3b. The movable element includes a slit 3c formed from the outer peripheral end of the yoke 3b to the yoke 3a, passing through the tooth 3b in the axial direction, and into which the lead wire 5a of the winding 5 is inserted through both ends of the yoke 3a in the axial direction. It is said that

In this embodiment, as shown in FIG. 1, seven annular teeth 3b are arranged on the outer periphery of a yoke 3a at equal intervals in the axial direction, and a winding 5 is installed between the teeth 3b. Six slots 4 are formed by the air gaps.

As shown in FIGS. 2 and 3, the slit 3c is provided from the outer peripheral end of the tooth 3b to the yoke 3a, and passes through the tooth 3b in the axial direction along the axial direction of the core 3. In this embodiment, the slit 3c axially penetrates each tooth 3b along the axial direction of the core 3, and communicates from one axial end of the yoke 3a to the other end. The slit 3c may be made to communicate with the inner periphery of the yoke 3a, or may be formed halfway in the radial direction of the yoke 3a as long as it is formed up to the yoke 3a.

Furthermore, in this embodiment, a total of six slots 4 are provided between the adjacent teeth 3b, 3b in FIG. 1, and the winding 5 is wound around the slots 4. It has been fitted. The winding 5 is a three-phase winding of U phase, V phase, and W phase. The six slots 4 are equipped with windings 5 in the order of W-phase, U-phase, V-phase, W-phase, U-phase, and V-phase from the left side in FIG.

Further, the U-phase, V-phase, and W-phase windings 5 are connected in series by connecting the lead wires 5a drawn out from the windings 5 for each phase, and the terminal ends of the windings 5 of each phase are connected in series. One end thereof is connected to each other by a lead wire 5b, and the other end of the terminal ends is connected to a cable 16 connected to an external power source (not shown). A lead wire 5a drawn out from the winding 5 is accommodated in a slit 3c provided in the core 3 and arranged on the inner circumferential side of the winding 5.

The armature 2 thus configured is attached to the outer periphery of the rod 11, which is an output shaft and is made of a non-magnetic material. Specifically, the armature 2 is fixed to the rod 11 by being held by annular sliders 12 and 13 whose left and right ends in FIG. 1 are fixed to the rod 11.

Further, in this embodiment, the field magnet 6 includes a cylindrical laminated magnet body M and a back yoke 8 fitted to the outer periphery of the laminated magnet body M, and is made of a cylindrical non-magnetic material. It is accommodated in an annular gap formed between an outer tube 7 and a cylindrical non-magnetic inner tube 9 inserted into the outer tube 7. The armature 2 is inserted into the field 6 so as to be movable in the axial direction.

The laminated magnet body M includes a plurality of permanent magnets 10a serving as a plurality of annular main magnetic poles which are alternately stacked and inserted in an axial direction into an annular gap between a cylindrical back yoke 8 and an inner tube 9, and a plurality of annular main magnetic poles. It is configured to include a permanent magnet 10b serving as a sub magnetic pole. In FIG. 1, the triangular marks written on the main pole permanent magnet 10a and the sub pole permanent magnet 10b indicate the direction of magnetization, and the magnetization direction of the main pole permanent magnet 10a is in the radial direction. The direction of magnetization of the permanent magnet 10b of the sub-pole is the axial direction. The permanent magnet 10a as the main pole and the permanent magnet 10b as the sub-pole are arranged in a Halbach arrangement, and on the inner peripheral side of the field 6, they are arranged so that S poles and N poles appear alternately in the axial direction. .

Furthermore, in the cylindrical linear motor 1 of this embodiment, the axial length L1 of the permanent magnet 10a of the main pole is longer than the axial length L2 of the permanent magnet 10b of the sub pole. By making the axial length L1 of the main pole permanent magnet 10a longer than the axial length L2 of the sub pole permanent magnet 10b, the magnetic resistance between the main pole permanent magnet 10a and the core 3 can be reduced. Since it can be made smaller and the magnetic field acting on the core 3 can be increased, the thrust of the cylindrical linear motor 1 can be improved. There is an optimal relationship between the axial length L1 of the main pole permanent magnet 10a and the axial length L2 of the sub pole permanent magnet 10b, and the axial length L1 of the main pole permanent magnet 10a and the sub pole permanent magnet If the axial length L2 of 10b is set to satisfy 0.2≦L2/L1≦0.5, the thrust will be 98% or more of the thrust when the value of L2/L1 is set to an ideal value. thrust can be secured. However, the relationship between the axial length L1 of the main pole permanent magnet 10a and the axial length L2 of the sub pole permanent magnet 10b is not limited to the above setting.

Furthermore, in the cylindrical linear motor 1 of this embodiment, the field 6 includes a back yoke 8 on the outer periphery of a laminated magnet body M made up of permanent magnets 10a and 10b. When the back yoke 8 is not provided, when the axial length L2 of the permanent magnet 10b of the auxiliary magnetic pole becomes shorter, the magnetic resistance outside the magnet in the axial center portion of the permanent magnet 10a of the main magnetic pole increases, and the field magnetic flux decreases. Therefore, the degree of improvement in the thrust of the cylindrical linear motor 1 when increasing the axial length L1 of the permanent magnet 10a of the main pole becomes small. On the other hand, if the back yoke 8 is provided on the outer periphery of the permanent magnets 10a and 10b, a magnetic path with low magnetic resistance can be secured, so that the magnetic resistance due to the shortening of the axial length L2 of the permanent magnet 10b of the sub-pole can be reduced. Growth is suppressed. Therefore, if the axial length L1 of the main pole permanent magnet 10a is made longer than the axial length L2 of the sub pole permanent magnet 10b, and a cylindrical back yoke 8 is provided around the outer periphery of the permanent magnets 10a and 10b, the cylindrical The thrust of the type linear motor 1 can be greatly improved. The thickness of the back yoke 8 may be set to a thickness suitable for suppressing an increase in external magnetic resistance of the permanent magnet 10a of the main pole.

Note that the permanent magnet 10b of the sub-pole is a permanent magnet having a higher coercive force than the permanent magnet 10a of the main pole. The residual magnetic flux density and coercive force in a permanent magnet are closely related to each other, and in general, increasing the residual magnetic flux density lowers the coercive force, and increasing coercive force lowers the residual magnetic flux density, which are contradictory to each other. In a relationship. In the Halbach arrangement, a large magnetic field is applied to the sub-pole permanent magnet 10b in the demagnetizing direction, so the coercive force of the sub-pole permanent magnet 10b is increased to suppress demagnetization and a large magnetic field is applied to the core 3. I'm trying to make it possible. On the other hand, the strength of the magnetic field acting on the core 3 depends on the number of lines of magnetic force of the permanent magnet 10a of the main pole. Therefore, a permanent magnet with a high residual magnetic flux density is used as the main pole permanent magnet 10a to apply a large magnetic field to the core 3. In this embodiment, in order to make the permanent magnet 10b of the auxiliary magnetic pole have a higher coercive force than the permanent magnet 10a of the main magnetic pole, the material of the permanent magnet 10b of the auxiliary magnetic pole has a coercive force higher than that of the material of the permanent magnet 10a of the main magnetic pole. It is a high quality material. Therefore, by selecting the materials, a combination of the main pole permanent magnet 10a and the sub pole permanent magnet 10b can be easily realized. In this embodiment, the permanent magnet 10a of the main pole is made of a material with high residual magnetic flux density mainly composed of neodymium, iron, and boron, and the permanent magnet 10b of the sub pole is made of a material containing dysprosium or teribium as the main components. It is composed of magnets that are difficult to demagnetize and have increased amounts of heavy rare earth elements such as

As described above, the core 3 is inserted into the inner peripheral side of the field 6, and the field 6 applies a magnetic field to the core 3. Note that since the field 6 only needs to apply a magnetic field to the movable range of the core 3, the installation range of the permanent magnets 10a and 10b may be determined according to the movable range of the core 3. Therefore, it is not necessary to install the permanent magnets 10a and 10b in the annular gap between the outer tube 7 and the inner tube 9 in a range where they cannot face the core 3.

The axial length of the back yoke 8 only needs to be longer than the total length of the laminated magnet body M, and may be equal to the total length of the laminated magnet body M. Further, when the axial length of the back yoke 8 is longer than the total length of the laminated magnet body M, the lines of magnetic force at the end of the laminated magnet body M do not leak into the atmosphere, and a decrease in the thrust of the cylindrical linear motor 1 can be prevented. In this way, in order to make the axial length of the back yoke 8 longer than the axial length of the laminated magnet body M, the laminated magnet body M must be longer than the maximum axial length that can be taken due to machining errors of the permanent magnets 10a and 10b. The axial length of the back yoke 8 may also be made longer.

Further, the left ends of the outer tube 7, back yoke 8, and inner tube 9 in FIG. 1 are closed by a cap 14, and the right ends of the outer tube 7, back yoke 8, and inner tube 9 in FIG. 1 are inserted into the inner periphery. It is closed by an annular head cap 15 that guides the axial movement of the rod 11.

Sliders 12 and 13 are in sliding contact with the inner periphery of the inner tube 9, and the sliders 12 and 13 allow the armature 2 to move smoothly in the axial direction together with the rod 11 without being eccentric with respect to the field 6. The inner tube 9 forms a magnetic gap between the outer periphery of the core 3 and the inner periphery of each permanent magnet 10a, 10b, and also plays the role of guiding the axial movement of the core 3 in cooperation with the sliders 12, 13. Fulfilling. The outer diameter of the core 3 is smaller than the inner diameter of the inner tube 9 and does not interfere with the inner tube 9, allowing the cylindrical linear motor 1 to expand and contract smoothly, but it may also slide into contact with the inner periphery of the inner tube 9. . Note that the inner tube 9 may be formed of a non-magnetic material, but if it is formed of a synthetic resin, the effect of improving the thrust density of the cylindrical linear motor 1 will be enhanced. If the inner tube 9 is made of non-magnetic metal, an eddy current will be generated inside the inner tube 9 when the armature 2 moves in the axial direction, and a force will be generated that hinders the movement of the armature 2. On the other hand, if the inner tube 9 is made of synthetic resin, no eddy current is generated, so that the thrust of the cylindrical linear motor 1 can be more effectively improved, and the mass of the cylindrical linear motor 1 can be reduced. Note that when the inner tube 9 is made of synthetic resin, friction and wear between it and the sliders 12 and 13 can be reduced if it is made of fluororesin. Moreover, the inner tube 9 may be formed of other synthetic resins, and the inner periphery of the inner tube 9 formed of other synthetic resins may be coated with a fluororesin in order to reduce friction and wear.

The cap 14 is provided with a connector 14a for connecting the cable 16 connected to the winding 5 to an external power source (not shown), so that the winding 5 can be energized from the external power source. Furthermore, the axial lengths of the outer tube 7, back yoke 8, and inner tube 9 are longer than the axial length of the core 3, and the core 3 extends from left to right in FIG. You can stroke to.

For example, if the electrical angle of the winding 5 with respect to the field 6 is sensed, the energization phase is switched based on the electrical angle, and the amount of current in each winding 5 is controlled by PWM control, the cylindrical linear motor 1 The thrust force and the moving direction of the armature 2 can be controlled. Note that the above-described control method is an example and is not limited thereto. In this way, in the cylindrical linear motor 1 of this embodiment, the armature 2 acts as a mover, and the field 6 acts as a stator. Further, when an external force that causes a relative displacement between the armature 2 and the field 6 in the axial direction acts, the cylindrical linear motor 1 is caused to It is possible to generate a thrust force that suppresses the relative displacement to damp vibrations and motions of the equipment caused by the external force, and it is also possible to regenerate energy by generating electric power from the external force.

As described above, the cylindrical linear motor 1 of the present invention includes an armature 2 having a cylindrical core 3 and a winding 5 installed in a slot 4 provided on the outer periphery of the core 3; The core 3 includes a cylindrical yoke 3a; A plurality of teeth 3b are arranged in the axial direction on the outer periphery of the yoke 3a, a plurality of slots 4 are provided between the teeth 3b and 3b, and a plurality of slots 4 are formed from the outer periphery of the teeth 3b to the yoke 3a and pass through the teeth 3b in the axial direction. It also has a slit 3c into which the lead wire 5a of the winding 5 is inserted.

In the cylindrical linear motor 1 configured in this way, the cross-sectional area of the slit 3c provided in the yoke 3a and the teeth 3b in the core 3 is only large enough to allow insertion of the lead wire 5a. There is no significant reduction in the magnetic path cross-sectional area. Further, since the lead wire 5a that connects the windings 5 is housed in the slit 3c of the core 3, the lead wire 5a is stored inside the winding 5, so that there is a gap between the core 3 and the field 6. There is no need to arrange the lead wire 5a between the two, and the radial distance between the two can be shortened. Therefore, according to the cylindrical linear motor 1, since magnetic saturation is less likely to occur in the core 3, the thrust can be improved compared to the conventional linear motor.

Note that, like the core 3 of the cylindrical linear motor 1A in the first modification of the embodiment shown in FIG. It may be formed by laminating the bodies C1 and C2. As shown in FIG. 4, the core segment C1 corresponding to both ends of the core 3 includes an annular yoke portion 20 corresponding to the yoke 3a in the core 3, teeth 3b provided on the outer periphery of the yoke portion 20, and teeth 3b provided on the outer periphery of the yoke portion 20. The yoke part 20 has a slit 22 extending from the outer periphery to the inner periphery of the yoke part 20, and has a C-shape in plan view. Further, the core segment C2 corresponding to areas other than both ends of the core 3 includes an annular yoke portion 23 corresponding to the yoke 3a in the core 3, a tooth 3b provided on the outer circumference of the yoke portion 20 at the axial center, and a tooth 3b provided on the outer circumference of the yoke portion 20 in the axial direction. A slit 25 communicating from the outer periphery to the inner periphery of the yoke portion 23 is provided, and the yoke portion 23 has a C-shape in plan view.

The core 3 is formed by laminating the five core division bodies C2 on the core division body C1 corresponding to the end portions of the core 3 configured in this way, and further laminating the core division body C1. Note that when the core 3 is viewed from the axial direction, the slit 22 of the core divided body C1 and the slit 25 of the core divided body C2 are arranged on a straight line in the axial direction to form a slit 3c. Then, a slot 4 is formed in which the winding 5 is mounted between the teeth 3b and 3b of the core division bodies C1 and C2 or between the teeth 3b and 3b of the core division bodies C2 and C2.

In order to attach the winding 5 to the core 3 configured in this way, as shown in FIG. (manufacturing process), all the windings 5 are connected in series with lead wires 5a for each phase. Thereafter, the core segment C2 is inserted between the windings 5, 5 from the radial direction of the winding 5, the core segments C2 are stacked on top of each other, and the winding 5 is attached to the core segments C2, C2. Further, the core divided body C1 is laminated on the core divided body C2 (core assembly process). At this time, the core segment C2 is brought closer to the winding 5 from the slit 25 side, and the core segment C2 is inserted between the windings 5 while inserting the lead wire 5a into the slit 25. Then, the core divided body C2 inserted between the windings 5 and 5 is brought closer to the adjacent core divided bodies C1 and C2, and while the yoke parts 20 and 23 are inserted into the winding 5, the core divided bodies C1 and C2 are Alternatively, the winding 5 is sandwiched between the teeth 3b, 3b of the core divided bodies C2, C2, and the winding 5 is sequentially installed in the slot 4 on the outer periphery of the core divided bodies C1, C2 or the core divided bodies C2, C2 while the core divided bodies are inserted. Stack C1 and C2. Note that the core divided bodies C1 and C2 are integrated by adhesion.

In this way, in the cylindrical linear motor 1A in which the core 3 is composed of the core divided bodies C1 and C2, which are divided into teeth 3b, the lead wires 5a of the winding 5 are connected in advance, and then the core divided bodies are connected. The core 3 can be assembled by laminating C1 and C2 and attaching the winding 5 to the outer periphery of the core divided bodies C1 and C2.

Therefore, if the core 3 in the cylindrical linear motor 1A is formed by stacking a plurality of annular core division bodies C1 and C2 divided in the axial direction so that each core 3 has one tooth 3b, After the lead wires 5a of the winding 5 are connected in advance, the slot 4 of the winding 5 can be attached while assembling the core 3. In the cylindrical linear motor 1A and the manufacturing method of the cylindrical linear motor 1A, since the winding 5 can be easily attached to the core 3 and the winding 5 can be connected, the cylindrical linear motor 1A can be manufactured easily. becomes. Note that the slits 22 and 25 communicate with the inner circumferences of the core divided bodies C1 and C2, but are formed halfway in the radial direction of the yoke parts 20 and 23 and do not communicate with the inner circumferences of the core divided bodies C1 and C2. It is not necessary. However, if the slits 22 and 25 extend to the inner periphery of the core division bodies C1 and C2, the slit 3c will penetrate to the inner periphery of the core 3 when the core 3 is formed, so that there will be no space between the core 3 and the rod 11. By providing an annular gap as shown in 4, the lead wires 5a can be placed on the inner circumference of the core 3, and the lead wires 5a connected to the windings 5 of different phases can be separated and insulated from each other. It becomes easier.

Further, like the core 3 of the cylindrical linear motor 1B in the second modified example of the embodiment shown in FIG. It may be formed by stacking annular core division bodies C3 and C4.
As shown in FIGS. 6 and 7, the core 3 includes one core segment C3 corresponding to one end of the core 3 and six core segments C4. The core division body C3 includes a perforated disk 30, a slit 30a formed from the outer periphery of the disk 30 toward the center, and three holes 30b on the same circumference that correspond to the yoke 3a and pass through the slit 30a. , 30c, and 30d. The slit 30a and the three holes 30b, 30c, and 30d are arranged at 90-degree intervals on the same circumference of the portion of the core segment C3 corresponding to the yoke 3a.

In addition, the core division body C4 includes an annular yoke portion 31a corresponding to the yoke 3a in the core 3, teeth 3b provided on the outer periphery of the yoke portion 31a, and teeth 3b provided on the outer periphery of the yoke portion 31a from the outer periphery of the teeth 3b toward the inner periphery of the yoke portion 31a. A slit 31c is formed, and three holes 31d, 31e, and 31f, which are the yoke portion 31a and are provided on the same circumference passing through the slit 31c, are provided. The slit 31c and the three holes 31d, 31e, and 31f are arranged at 90 degree intervals on the same circumference of the yoke portion 31a corresponding to the yoke 3a of the core segment C4.

The core 3 is formed by stacking six core division bodies C4 on the core division body C3 corresponding to the end portion of the core 3 configured in this way. Specifically, as shown in FIG. 8, the core divided bodies C3 and C4 are stacked with the slits 30a and 31c facing each other and the openings facing upward. The core divided body C4 is arranged to face one of the holes of the adjacent core divided body C4, and from the leftmost core divided body C3 up to the fourth layer, counting by the number of laminated layers, the phases are set by 90 degrees in the same direction in the circumferential direction. The layers are stacked while being shifted. That is, in FIG. 8, the opening of the slit 31c of the second-layer core division body C4 is directed upward, and the opening of the slit 31c of the third-layer core division body C4, indicated by a broken line, is directed to the left. The opening of the slit 31c of the core division body C4 of the layer is directed downward. The fifth layer of core divided bodies C4 is stacked on the fourth layer of core divided bodies C4 with a phase shift of 180 degrees in the same direction. That is, the opening of the slit 31c of the fifth layer core division body C4 is directed upward. The core divided bodies C4 from the fifth layer to the seventh layer are stacked in the same direction with their phases shifted by 90 degrees. Therefore, the core divided bodies C4 from the fifth layer to the seventh layer are stacked in the same direction as the core divided bodies C4 from the second layer to the fourth layer .

When the core division bodies C3 and C4 are stacked in this way, the slits 30a and 31c and the three holes 30b, 30c, 30d, 31d, 31e and 31f are arranged at 90 degree intervals on the same circumference, so as shown in FIG. As shown in FIG. 8, the slit 31c faces one of the holes 30b, 30c, 30d of the adjacent core division body C3 or the holes 31d, 31e, 31f of the core division body C4 for each different layer. The holes located on the right side of the core dividing body C4 of each layer are not opposed to each other. Furthermore, the three holes 31d, 31e, and 31f of the core divided body C4 face any of the holes 31d, 31e, and 31f or the slit 31c of the adjacent core divided body C4, but in FIG. The hole arranged on the right side of C4 does not communicate with the slits 30a and 31c, but communicates only with one of the holes 30b, 30c, 30d, 31d, 31e, and 31f in the other core division bodies C3 and C4. .

In this way, among the three holes of the core dividing bodies C3 and C4, one hole is not connected to the slits 30a and 31c but is lined up in a straight line in the axial direction of the core 3 from one end of the core 3 to the other end. One axial hole is formed in communication. On the other hand, the slit 31c in the core division body C4 is connected to the slit 31c of the core division body C4 three places ahead through any of the holes 31d, 31e, and 31f of the two core division bodies C4. In other words, the slots 4 between the U, V, and W phases of the core 3 are communicated with each other through the slit 31c and the holes 31d, 31e, and 31f, while the holes that do not face the slit 31c communicate with each other from one end of the core 3 in the axial direction to the other end. An axial hole is formed therethrough. Note that the shapes of the tips of the slits 30a and 31c are arbitrary, and may be shaped to match the holes 30b, 30c, 30d, 31d, 31e, and 31f.

To manufacture the armature 2 by attaching the winding 5 to the core 3 configured in this way, the winding 5 is attached to each core segment C4, and the lead wire 5a is passed through the slit 31c. . The core divided bodies C4 assembled with the winding 5 in this manner are laminated with their phases shifted in the circumferential direction in the manner described above. The lead wire 5a is connected to the winding 5 of the same phase through the hole of the two-layer core divided body C4 stacked on the core divided body C4 to which the winding 5 is attached, and through the slit 31c of the core divided body C4 three layers ahead. Ru. In the step of stacking the core divided bodies C3 and C4, a key K is inserted into a hole that forms an axial hole that passes through the core 3 without facing the slit 31c, as shown in FIG. By inserting the key K in this way, the core division body C4 is positioned in the circumferential direction, and the alignment of the slit 31c and the holes 31e, 31e, 31f becomes very easy, so that the manufacturing work of the core 3 is facilitated. It becomes very easy. Note that since the core divided bodies C3 and C4 are bonded to each other, the key K can be removed once the assembly of the core 3 is completed.

In the cylindrical linear motor 1B configured in this way, the winding 5 is attached to the core segment C4 in advance to form an assembly, and the assembled core segments C4 are sequentially stacked and the lead wires 5a are connected. The core 3 can be assembled using the following steps. In addition, if the core 3 is made into core divided bodies C3 and C4 and provided with slits 30a and 31c and three holes 30b, 30c, 30d, 31d, 31e and 31f, respectively, the U phase, V phase, and W phase In one core division body C3, C4, each lead wire 5a of the winding 5 of each phase does not coexist in the same slit 30a, 31c or the same hole 30b, 30c, 30d, 31d, 31e, 31f, but is different. They are distributed and housed in slits and holes. Therefore, in the cylindrical linear motor 1B configured in this way, the insulation properties of the lead wires 5a of the windings 5 of each of the U-phase, V-phase, and W-phase can be improved.

In addition, in order to isolate the lead wires 5a of the windings 5 of the U-phase, V-phase, and W-phase from each other for each phase to improve insulation, the core divided body is formed into an annular shape as shown in FIG. The first core segment C5 may constitute one end of the core 3, and a plurality of second core segments C6 may be annular and stacked on the first core segment C5. The first core division body C5 includes holes 32a provided at 120 degree intervals on the same circumference of a portion corresponding to the yoke. The second core division body C6 has a slit 33a formed from the outer periphery to a portion corresponding to the yoke, and two holes 33b and 33c that accommodate the lead wire 5a on the same circumference passing through the slit 33a in the portion corresponding to the yoke. It is equipped with Further, the slit 33a and the two holes 33b and 33c in the second core division body C6 are arranged at intervals of 120 degrees. Then, if the six second core division bodies C6 are stacked with respect to the first core division body C5 while being shifted by 120 degrees in the circumferential direction, they will always be adjacent to the slit 33a of the second core division body C6. One of the holes 33b and 33c of the second core division body C6 faces each other, and the remaining holes also face each other. In this case, it is no longer possible to insert the key K to facilitate positioning when assembling the core 3, but the lead wires 5a of each phase can be accommodated individually in the slits and holes, and the windings 5 of each phase can be well insulated. can. Moreover, when forming the core 3 by laminating a plurality of second core division bodies C6 on the first core division body C5 shown in FIG. They are stacked clockwise or counterclockwise with a phase difference of 120 degrees in the circumferential direction, and the slits 33a in the second core division body C6 are evenly distributed throughout the core 3 with a phase difference of 120 degrees in the circumferential direction. be done. In this way, the slits 33a of the second core segment C6 are arranged in a well-balanced manner in the circumferential direction throughout the core 3, so the attraction force that the core 3 receives from the field magnet 6 is balanced in the radial direction, and the core 3 It becomes difficult to receive a large attractive force from the magnet 6 that causes eccentricity in the radial direction. Since the slits 33a are evenly arranged every 120 degrees in the circumferential direction throughout the core 3, a large frictional force is not generated between the sliders 12, 13 and the inner tube 9, and the cylindrical linear motor 1 can be expanded and contracted smoothly without causing a decrease in thrust.

In order to evenly arrange the slits at every 120 degrees throughout the core 3, in addition to the above-described structure, the core 3 of the cylindrical linear motor 1C in the fourth modification of the embodiment shown in FIG. As shown, the core 3 may be composed of a first core segment C7 forming one end of the core 3 and a plurality of second core segments C8.

As shown in FIGS. 11 and 12, the first core division body C7 is annular and includes six holes 34a provided at 60 degree intervals on the same circumference of a portion of the core 3 corresponding to the yoke. . The hole 34a passes through the first core division body C7 in the axial direction, and is located on the same circumference so that it can face a slit 35c and five holes 35d, 35e, 35f, 35g, and 35h in the second core division body C8, which will be described later. It is set in.

Further, as shown in FIGS. 11 and 12, the second core segment C8 includes an annular yoke portion 35a corresponding to the yoke in the core 3, and an annular portion provided at the axial center of the outer circumference of the yoke portion 35a. Teeth 35b having a thinner wall than the yoke part 35a, slits 35c communicating from the outer periphery of the teeth 35b to the yoke part 35a, and five teeth passing through the yoke part 35a in the axial direction on the same circumference passing through the slits 35c in the yoke part 35a. It has holes 35d, 35e, 35f, 35g, and 35h, and has a C-shape in plan view. The slit 35c and the five holes 35d, 35e, 35f, 35g, and 35h in the second core division body C8 are arranged at 60 degree intervals on the same circumference that is the yoke portion 35a and passes through the slit 35c.

The core 3 is formed by stacking six second core segments C8 on the first core segment C7 corresponding to one end of the core 3 configured in this manner. Specifically, the first core divided body C7 is arranged such that the slit 35c and holes 35d, 35e, 35f, 35g, and 35h of the second core divided body C8 respectively face the hole 34a of the first core divided body C7. The second core divided body C8 is superimposed on the second core divided body C8. Subsequently, the six second core divided bodies C8 are stacked while being shifted by 120 degrees in the circumferential direction. Then, as shown in FIG. 13, the hole 35e or hole 35g of the adjacent second core divided body C8 always faces the slit 35c of the second core divided body C8, and the remaining holes also face each other.

In this way, the second core segment C8 is laminated by being rotated 120 degrees in one direction in the circumferential direction with respect to the adjacent second core segment C8, and the slit 35c of the adjacent second core segment C8 They are arranged with a phase difference of 120 degrees.

The holes 35d, 35f, 35h of the second core divided body C8 are opposed to any one of the holes 35d, 35f, 35h of the adjacent second core divided body C8, and the six holes of the first core divided body C7 are opposed to each other. The hole 34a faces the slit 35c and the five holes 35d, 35e, 35f, 35g, and 35h. Therefore, when the core 3 is formed by laminating the second core division body C8 on the first core division body C7, three holes connected to the slits 35c are formed along the axial direction of the core 3, and the core 3 Three axial holes not connected to the slit 35c are formed along the axial direction. The lead wires 5a of the U-phase, V-phase, and W-phase windings 5 are housed in the three axial holes connected to the slits 35c in the core 3 in a distributed manner without coexisting together. Therefore, in the cylindrical linear motor 1C configured in this way, the insulation properties of the lead wires 5a of the windings 5 of the U-phase, V-phase, and W-phase can be improved.

In the cylindrical linear motor 1C of the present embodiment, the slits 35c of the second core segment C8 are arranged in a well-balanced manner in the circumferential direction throughout the core 3, so that the attraction force that the core 3 receives from the field 6 is reduced. Balanced in the radial direction, the core 3 is less susceptible to large attraction forces from the field 6 that make it eccentric in the radial direction. In this way, since the slits 35c are evenly arranged at every 120 degrees in the circumferential direction throughout the core 3, a large frictional force is not generated between the sliders 12, 13 and the inner tube 9, and the cylindrical linear The motor 1 can be smoothly expanded and contracted without causing a decrease in thrust force.

In addition, in order to manufacture the armature 2 by attaching the winding 5 to the core 3 configured in this way, the winding 5 is attached to each second core segment C8, and the lead wire 5a is inserted into the slit 35c. Pass it through. The second core segment C8 assembled with the winding 5 in this manner is laminated with a phase shift in the circumferential direction in the manner described above. The first core segment C7 may be stacked on the second core segment C8 prior to the stacking of the second core segments C8, or the second core segment C8 may be stacked after the second core segment C8 is stacked. may be stacked on top of each other.

The lead wire 5a passes through the hole of the second core division body C8 of two layers stacked on the second core division body C8 to which the winding 5 is attached, and passes through the slit 35c of the second core division body C8 three layers ahead. Connected to winding 5. In the step of stacking the first core division body C7 and the second core division body C8, a key K1 made of a round bar is inserted into one of the three axial holes that penetrate the core 3 without being connected to the slit 35c. Insert it. By inserting the key K1 in this way, the first core division body C7 and the second core division body C8 are positioned in the circumferential direction, so that the slit 35c and the holes 34a, 35d, 35e, 35f, 35g, and 35h are aligned. Positioning becomes very easy. Further, in this embodiment, the key K1 used during the manufacturing work of the core 3 is left in the core 3 without being removed, and the key K1 is also separated from the first core segment C7 and the second core segment C8 in the core 3. It is used as a part to prevent Note that the key K1 may be made of a non-magnetic material or a magnetic material, but in order to balance the radial attractive force that the core 3 receives from the field 6, a non-magnetic material It is preferable to make it with

As mentioned above, the key K1 is inserted into one of the three axial holes that are not connected to the slit 35c in the core 3, but nothing is inserted into the remaining two axial holes and they are left open. . The sliders 12 and 13 in the cylindrical linear motor 1C of this embodiment are each provided with through holes (not shown) that are not connected to the slit 35c and that communicate with the two axial holes in which the key K1 is not inserted. The two chambers R1 and R2 on both sides of the armature E in the axial direction in the inner tube 9 are not connected to the slit 35c, and the two axial holes and these through holes are not connected to the slit 35c and the key K1 is not inserted. communicated by. In this way, the two axial holes that are not connected to the slit 35c and into which the key K1 is not inserted communicate air between the chambers R1 and R2 and enable gas exchange between the chambers R1 and R2. Since it functions as an escape hole, the smooth expansion and contraction of the cylindrical linear motor 1C is not hindered by the pressure increase in the compressed chambers R1 and R2 when the cylindrical linear motor 1C expands and contracts. Therefore, the cylindrical linear motor 1 can smoothly expand and contract, and the thrust force does not decrease due to the increase in pressure in the chambers R1 and R2.

Although the preferred embodiments of the present invention have been described in detail above, modifications, variations, and changes can be made without departing from the scope of the claims.

1, 1A, 1B, 1C... Cylindrical linear motor, 2... Armature, 3... Core, 3a... Yoke, 3b... Teeth, 3c, 22, 30a, 31c, 33c, 35c...Slit, 4...Slot, 5...Winding, 6...Field, 30b, 30c, 30d, 31d, 31e, 31f, 32a, 33b, 33c, 34a, 35d, 35e, 35f, 35g, 35h... Hole, C1, C2, C3, C4... Core divided body, C5, C7... First core divided body, C6, C8... Second core divided body, K, K1...key

Claims (5)

an armature having a cylindrical core and a winding installed in a slot provided on the outer periphery of the core;
a field magnet having a cylindrical shape, into which the armature is inserted movably in the axial direction, and in which N poles and S poles are alternately arranged in the axial direction;
The core includes a cylindrical yoke, a plurality of teeth arranged axially on the outer circumference of the yoke, and is formed from an outer circumferential end of the teeth to the yoke, passing through the teeth in the axial direction, and extending through the winding. It has a slit into which a lead wire is inserted, and is formed by stacking a plurality of annular core segments divided in the axial direction so that each has one tooth,
The core division body is
an annular first core segment forming one end of the core and having three holes arranged at 120 degree intervals on the same circumference of a portion corresponding to the yoke and accommodating the lead wire;
a plurality of second core divided bodies having the slit and two holes corresponding to the yoke and accommodating the lead wires on the same circumference passing through the slit;
The slit and the two holes in the second core division body are arranged at 120 degree intervals on the same circumference.
A cylindrical linear motor characterized by: an armature having a cylindrical core and a winding installed in a slot provided on the outer periphery of the core;
a field magnet having a cylindrical shape, into which the armature is inserted movably in the axial direction, and in which N poles and S poles are alternately arranged in the axial direction;
The core includes a cylindrical yoke, a plurality of teeth arranged axially on the outer circumference of the yoke, and is formed from an outer circumferential end of the teeth to the yoke, passing through the teeth in the axial direction, and extending through the winding. It has a slit into which a lead wire is inserted, and is formed by stacking a plurality of annular core segments divided in the axial direction so that each has one tooth,
The core division body has three holes on the same circumference that correspond to the yoke and pass through the slit,
The slit and the three holes are arranged at 90 degree intervals on the same circumference,
A cylindrical linear motor characterized in that two of the three holes are used as holes for accommodating the lead wire, and a key can be inserted into the remaining holes. an armature having a cylindrical core and a winding installed in a slot provided on the outer periphery of the core;
a field magnet having a cylindrical shape, into which the armature is inserted movably in the axial direction, and in which N poles and S poles are alternately arranged in the axial direction;
The core includes a cylindrical yoke, a plurality of teeth arranged axially on the outer circumference of the yoke, and is formed from an outer circumferential end of the teeth to the yoke, passing through the teeth in the axial direction, and extending through the winding. It has a slit into which a lead wire is inserted, and is formed by stacking a plurality of annular core segments divided in the axial direction so that each has one tooth,
The core division body is
an annular first core division body having six holes arranged at 60 degree intervals on the same circumference of a portion corresponding to the yoke and constituting one end of the core;
a plurality of second core division bodies that correspond to the slit and the yoke and have five holes on the same circumference passing through the slit;
The slits and the five holes in the second core division body are arranged at 60 degree intervals on the same circumference,
A cylindrical linear motor characterized in that the lead wires are accommodated in three holes of the first core division body and a slit and two holes of the second core division body. A key characterized in that the core division bodies are communicated with each other in a stacked state and are inserted into one of the holes not connected to the slit to position the core division body in the circumferential direction. The cylindrical linear motor according to item 2 or 3 . The cylindrical linear motor according to any one of claims 1 to 4 , wherein the slit communicates with an inner periphery of the yoke.

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