JP7296142B2 - motor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a rotating electric machine, and more particularly to a rotating electric machine suitable for efficient operation.

As a technique for changing the characteristics of a motor as a rotating electrical machine, switching the connection form of internal windings has been proposed, as disclosed in Patent Document 1 and Patent Document 2. For example, Patent Document 1 is a technique related to a motor for a machine tool, in which a coil composed of three phases constituting an AC circuit is used as a stator, and the coils constituting each phase are composed of a plurality of coils with different numbers of turns. . One or a plurality of coils are selectively connected in series so that the number of turns of the entire coil is reduced during high-speed rotation and the number of turns of the entire coil is increased during low-speed rotation.

Further, Patent Document 2 mainly discloses a technique related to a motor for a starter generator for an electric power tool or an automobile. Similarly to the motor disclosed in Patent Document 1, the motor disclosed in Patent Document 2 also uses a coil composed of three phases as a stator. Each phase is composed of a plurality of coils, and a switching circuit (switching device) capable of switching the connection of the plurality of coils constituting each phase in series or in parallel is provided. By adopting such a configuration, in series connection, the magnetic field excited by the coil is strong and torque can be improved, while in parallel connection, the magnetic field is weak and high speed rotation can be realized.

Further, Patent Documents 3 and 4 describe that, in a coreless motor having a plurality of phases, the characteristics of the motor can be made different by defining the connection method of each phase as series or parallel. Furthermore, Japanese Patent Application Laid-Open No. 2002-300000 describes that a circuit is used to switch the connection method of three-phase coils between series and parallel in a motor having fixed coils.

Japanese Patent No. 3596711 Japanese Patent Publication No. 2010-537621 Japanese Unexamined Patent Application Publication No. 2014-121102 Japanese Patent Application Laid-Open No. 2019-54628 JP 2011-229221 A

According to the techniques disclosed in Patent Documents 1 and 2, it is certainly possible to change the characteristics of the motor and achieve the actions of a plurality of motors with a single motor. However, with the technique disclosed in Patent Document 1, the number of turns of the coil is substantially changed, so there is a possibility that the torque will be extremely reduced in the high speed range. Further, the technique disclosed in Patent Document 2 has a large self-inductance due to the influence of the iron core, and there is concern that a time lag may occur between switching and characteristic change.

In addition, as in the coreless motors disclosed in Patent Documents 3 and 4, when a circuit for switching the connection method of the coil is added, it is generally necessary to provide a space for arranging the circuit outside the casing. occur. For this reason, even if a motor with a small capacity is manufactured by using small coils, it may be difficult to reduce the size of the motor as a whole.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to solve the above problems and to provide a motor that can reduce the space required for arranging a circuit for switching the coil connection method, thereby facilitating miniaturization of the machine as a whole. do.

A motor according to the present invention for achieving the above object comprises a housing, a non-rotating stator coil which is configured to form a cylindrical shape with a wire rod and is cantilever supported, and a stator coil spaced apart from the stator coil. and a rotor with permanent magnets located on opposing surfaces of the coils, wherein the stator coils are composed of a plurality of phases, each phase composed of a plurality of coils, and the coils constituting each phase. A circuit section is provided in which the connection form can be switched between a serial form and a plurality of parallel forms, the circuit section is housed in the housing, and the circuit section is composed of a disk-shaped substrate and connected to the end portion of the stator coil. The circuit portion is made of a semiconductor element, and the stator coil has a deformation-resistant layer on at least one of the inner side and the outer side of the stator coil. 1. A motor characterized by a deformation-resistant coil body provided with a deformation-resistant coil body, or a deformation-resistant coil body having an annular reinforcement ring formed of metal at a free end thereof.

Further, in the motor having the characteristics described above, the coil switching board is made disc-shaped , so that the coil switching board can be efficiently accommodated in the cylindrical housing formed in accordance with the shape of the stator coil. It becomes possible.

Furthermore, in the motor having the characteristics described above, the coil switching board is arranged at the end of the stator coil. With such characteristics, the coil switching board can be used as a reinforcing ring for the stator coil.

Further, in the motor having the characteristics described above , if the circuit section is composed of one or a plurality of semiconductor elements, the rotary electric machine itself can be made smaller and lighter, and the internal wiring can be reduced. It is also possible to achieve simplification or the like.

In addition, the motor having the characteristics described above may include a rotating shaft that rotates in synchronization with the rotor, and the rotating shaft may be provided with blades at a portion located within the housing. can. With such features, it is possible to circulate air in the housing and achieve a cooling effect.

A motor according to the present invention for achieving the above object includes a housing, a non-rotating stator coil having an annular shape, and a permanent magnet spaced apart from the stator coil and positioned on the opposite surface of the stator coil. and a rotor, wherein the stator coil is composed of a plurality of phases, each phase is composed of a plurality of coils, and the connection form of the coils constituting each phase is divided into a series form and a plurality of parallel forms. A switchable circuit portion is provided in the housing, and the circuit portion is constructed of a disc-shaped substrate to be proximate to the end of the stator coil and to the end of the stator coil. The circuits are arranged in parallel , the circuit section is composed of a semiconductor element , the semiconductor element has a set OFF period both before and after coil switching, and the stator coil is arranged inside or outside the stator coil. A deformation resistant coil body having a deformation resistant layer provided on at least one side surface thereof, or a deformation resistant coil body having an annular reinforcing ring made of metal disposed at a free end. This is because it is possible to effectively prevent the occurrence of a short circuit when switching the connection format of the coil.
Further, in the motor having the characteristics as described above, the stator coil is preferably provided with a deformation-resistant layer.

Further, the motor having the characteristics described above is used by being submerged in water, and the housing in which the stator coil and the rotor are housed is determined in the direction of propulsion, and the extending portion of the rotating shaft is arranged in the opposite direction to the direction of propulsion. The structure can be such that the housing protrudes from the side to the outside of the housing .

In addition, the present invention does not depend only on the number of rotations, but also switches based on the output torque of the motor (substantially proportional to the phase current of the motor, hereinafter simply referred to as torque) or the motor phase current (hereinafter simply referred to as current). is desirable. This is because, if switching is based solely on the number of revolutions, the expected torque cannot be obtained for the amount of current consumed.

According to the motor having the characteristics described above, the space for arranging the circuit for switching the coil connection method can be reduced, and the size of the machine as a whole can be reduced.

1 is a side sectional view showing a schematic configuration of a motor according to the present invention; FIG. It is a figure which shows the cross-sectional structure of a stator coil. It is a figure which shows the cross-sectional structure of the litz wire which comprises the stator coil which concerns on embodiment. It is a figure which shows the example which formed the coil switching board|substrate in the shape of a ring. FIG. 4 is a diagram showing a circuit configuration of a stator coil in the motor according to the first embodiment, and is a diagram showing an example of a case where coils forming respective phases are connected in series. FIG. 4 is a diagram showing a circuit configuration of a stator coil in the motor according to the first embodiment, and is a diagram showing an example in which coils forming each phase are connected in parallel. 7 is a graph showing relational characteristics between torque and rotation speed, and between torque and current when the connection method of the coils forming the stator coil is switched. 5 is a graph showing changes in characteristics when the motor is operated by switching the connection method of the coils forming the stator coil. 5 is a graph showing changes in output characteristics when the motor is operated by switching the connection method of the coils forming the stator coil, and zones for switching according to the situation. FIG. 6 is a diagram showing the circuit configuration of a stator coil in a motor according to a second embodiment, and is a diagram showing an example in which all four coils forming each phase are directly connected. FIG. 4 is a diagram showing the circuit configuration of a stator coil in a motor according to a second embodiment, in which two of the four coils forming each phase are connected in series, and the series-connected sets of coils are connected in parallel; It is a figure which shows the example of. FIG. 6 is a diagram showing a circuit configuration of a stator coil in a motor according to a second embodiment, and is a diagram showing an example in which all four coils forming each phase are connected in parallel. 9 is a graph showing changes in characteristics when the motor according to the second embodiment is operated by switching the connection method of the coils forming the stator coils. FIG. 4 is a diagram showing a specific example of operation switching when a three-stage switching motor is applied to a vehicle (relationship between change in rotation speed and connection switching). FIG. 4 is a diagram showing a specific example of operation switching when a three-stage switching motor is applied to a vehicle (relationship between speed change and connection switching). FIG. 4 is a diagram showing a specific example of operation switching when a three-step switching motor is applied to a vehicle (relationship between change in road surface inclination and connection switching). It is a figure which shows the application form provided with 12 coils and 5 circuit parts in 1 phase. FIG. 10 is a cross-sectional view showing an example of the arrangement of coils when 12 coils are used; It is a diagram showing an example of a circuit in a six-stage switching motor, and a partially enlarged view of a portion surrounded by a dashed line A is shown in the figure. 20 is a table showing switching of circuit units and changes in connection state in FIG. 19; FIG. 4 is a diagram showing a circuit example in which a stator coil is composed of two phases; FIG. 4 is a schematic diagram showing an example of a two-phase stator coil in which coils of respective phases are connected in series; FIG. 3 is a schematic diagram showing an example of a two-phase stator coil in which respective phase coils are connected in parallel; FIG. 4 is a diagram showing a circuit example in which a stator coil is composed of five phases; FIG. 3 is a schematic diagram showing an example of a case where coils of each phase are connected in series in a five-phase stator coil; FIG. 5 is a schematic diagram showing an example in which coils of each phase are connected in parallel in five-phase stator coils. FIG. 4 is a diagram showing the relationship between a clock and Lo and Hi in various command signals when the circuit unit is configured by switching elements; FIG. 4 is a diagram showing a configuration example of a control unit that outputs a command signal to a circuit unit using switching elements; FIG. 3 is a diagram showing an example of a circuit of blocks that configure each phase; 1 is a diagram showing an example of a case in which a coreless rotating electrical machine according to the present invention is applied to a rotating electrical machine for underwater use; FIG. FIG. 3 is a diagram showing an example of a case where the coreless rotating electrical machine according to the present invention is applied to a self-propelled rotating electrical machine that uses underwater; It is a figure which shows the example in the case of making a coil switching board|substrate into a disc shape. FIG. 10 is a diagram showing an example of a type of rotary electric machine that discharges water vapor obtained by evaporating cooling water in the rotary electric machine used underwater.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a motor according to the present invention will be described in detail with reference to the drawings.

[Basic configuration]
First, the basic configuration of a motor 10 according to this embodiment will be described with reference to FIGS. 1 to 3. FIG. The motor 10 according to the present embodiment is a so-called coreless motor that is basically composed of a housing 12, a rotating shaft 14, a stator coil 18, a rotor 16, and a coil switching board 24. As shown in FIG. The housing 12 is an element forming an outer shell, and accommodates the rotating shaft 14, the stator coil 18, the rotor 16, and the coil switching board 24 in an internal space. Rotating shaft 14 is arranged with stator 13 provided inside housing 12 as a base point, and has projections outside housing 12. Bearings 13a and 12a are provided at intersections of stator 13 and housing 12, respectively. is rotatably supported by

Further, the motor 10 according to the present embodiment is an example related to a general-purpose motor for land use, and has a configuration in which the rotary shaft 14 is provided with the blades 14a. The blades 14a are elements that play a role as a so-called cooling fan, and play a role 14a in circulating the gas inside the housing 12 by rotating the rotating shaft 14. As shown in FIG. With such an action, heat generation from the coil can be suppressed, and the function of the coil switching board 24 can be ensured. In the example shown in FIG. 1, the blades 14a are provided between the stator coil 18, which will be described later in detail, and the end of the housing 12 from which the rotating shaft 14 protrudes. (the inner peripheral region of the inner yoke 16b). In this embodiment, air is expected to flow in and out through through holes (not shown) provided in the housing 12 due to the air pressure difference caused by the rotational action of the blades 14a. may be provided so that the rotation of the rotor 16 causes a change in atmospheric pressure. Therefore, the blade 14a is one form of cooling means applied to the rotating electric machine of the present invention, and the cooling means is not limited to this.

The stator coil 18 is configured in an annular shape by a group of coils divided into a plurality of phases (three phases of U phase, V phase and W phase in this embodiment) (see FIG. 2). The U-phase, V-phase, and W-phase constituting the stator coil 18 are each composed of a plurality of coils constituting poles. In the form shown in FIG. 2, each phase is divided into 1/2 (that is, divided into two equal parts), and the first coil U ₁ , the second coil U ₂ , the first coil V ₁ , the second coil V ₂ , the first coil W ₁ and a second coil W ₂ . As a more specific example, the phase that constitutes the inner annular coil body is the U phase, the phase that is located radially outside the inner annular coil body is the V phase, and the phase that is located outside the V phase. is a W phase, and each phase has a first coil (U ₁ , V ₁ , W ₁ ) and a second coil (U ₂ , V ₂ , W ₂ ). It should be noted that the U-phase, V-phase, and W-phase from the inside is just an example, and different orders and overlapping methods may be used. Also, in FIG. 2, each phase is sequentially shifted by approximately 1/3 of the electrical angle in the circumferential direction. The stator coil 18 having such a configuration is configured such that one end surface thereof is supported by the stator 13, which is a fixed member.

Here, for the sake of simplification of explanation, the phrase "shifted in the circumferential direction by approximately 1/3" is used, but strictly speaking, the U-phase, the V-phase, and the W-phase shift by 120° in electrical angle. In the mechanical angle (actual angle), the V phase is shifted by 120° and the W phase by 240° with respect to the U phase in the case of two poles. In the case of four poles, the V phase is shifted by 60° or 240° and the W phase by 120° or 300° with respect to the U phase. In the case of 6 poles, the V phase is 40°, 160°, 280° with respect to the U phase, and the W phase is 80°, 200°, 320° with respect to the U phase. 210°, 300°, W phase shifts 60°, 150°, 240°, 330°. In this way, 10 poles and 12 poles are shifted according to the law. The U-phase, V-phase, and W-phase each deviate by 120° in electrical angle, but since the deviation angle changes depending on the number of poles when expressed in mechanical angle, FIG.

Further, the rotor 16 has a cylindrical outer yoke 16c, an inner yoke 16b, and a permanent magnet 16a. The outer yoke 16c is an element located on the outer peripheral side of the stator coil 18 described above (on the outer peripheral side in the radial direction with respect to the center of the ring), and the inner yoke 16b is an element located on the inner peripheral side of the stator coil 18. be. Further, in the motor 10 according to the present embodiment, the permanent magnet 16a is provided inside the outer yoke 16c and on the surface facing the stator coil 18. As shown in FIG.

In the example shown in FIG. 1, a supporting member 17 is arranged between the inner yoke 16b and the rotating shaft 14 so that the rotation of the rotor 16 and the rotating shaft 14 are synchronized. In the example shown in FIG. 1, the supporting member 17 is provided on the base end side of the rotor 16 (the side on which the coil switching board 24 described later in detail is arranged) and the tip end side. With such a configuration, it is possible to suppress shaking when the rotor 16 rotates.

A coreless motor having such a configuration can obtain a large output and torque compared to the size of the motor 10 because the power generation source and the rotating shaft 14 are separated from each other. Moreover, since the stator coil 18 does not have an iron core, the self-inductance can be kept small.

Further, in the motor 10 having such a configuration, when the stator coil 18 is formed, a litz wire as shown in FIG. 3 is used for the winding and the shape is formed by coating with an insulating layer. The litz wire is a so-called stranded wire formed by bundling a plurality of conductive wires 18a, and the outer circumference of each conductive wire 18a is covered with an enamel layer 18b. Furthermore, in each of the embodiments described below, an outer skin layer 18c made of a fibrous material such as glass fiber is provided on the outer periphery of the conductive wire 18a (the conductive wire 18a as a bundle) that constitutes the twisted wire.

The coil switching board 24 is an element for arranging the circuit section 20 for switching the connection type of the coils forming the stator coil 18, and has a ring-shaped outer appearance (see FIG. 4). Here, in FIGS. 5 and 6, etc., the circuit section 20 is shown mechanically for the sake of form, but when arranged on the coil switching board 24, as shown in FIG. Good to configure. Further, since FIG. 4 schematically shows wirings and elements, their shape, layout, number, etc. are different from the actual ones. For example, in FIG. 4, three lines are representatively drawn as lines from the stator coil 18, but actually the same number of lines as the number of terminals of the coil are connected. As shown in FIG. 4, the number of wires may be reduced by attaching a driver to the coil switching board 24 and connecting via the driver. Similarly, with respect to the wiring on the substrate, a plurality of wirings are provided on the actual substrate. Further, the coil switching board 24 may be provided with a driver for controlling the stator coil 18 and a switching command device (control unit 22) for outputting a signal for switching the connection type of the coil. good. As shown in FIG. 4 in which the driver and the switching command device are separated from the coil switching board 24 and connected by wiring, the driver and the switching command device may be provided outside the housing 12 or the like. Here, the wiring for connecting the driver and the coil switching board 24 is schematically shown as one, but in practice, it is assumed that a plurality of wirings are provided in the same manner as described above. Moreover, the number of signal lines from the switching command device to the coil switching board 24 may be plural.

The coil switching board 24 is arranged inside the housing 12 so that the ring-shaped plate surface is parallel to and coaxial with the annular cross section of the stator coil 18 . In the example shown in FIG. 1, the coil switching board 24 is arranged at the rear end of the stator 13 . With such a configuration, it is not necessary to dispose a substrate for disposing the circuit section 20 outside the housing 12 . Therefore, the appearance of the motor 10 can be made smaller. Moreover, since the distance between the stator coil 18 arranged in an annular shape and the coil switching board 24 can be reduced, the wiring between the two can be facilitated. The present invention is applied to a coreless rotary electric machine having such a basic configuration. Coil switching in a coreless rotating electrical machine does not generate spike voltages and therefore does not damage the switching elements. This point was first conceived by the inventors of the present application, and is a unique idea.

[First embodiment]
In the motor 10 having such a basic configuration, as shown in FIGS. 5 and 6, two coils (a first coil U ₁ , a second coil U ₂ and a first coil V) constitute the stator coil 18 for each phase. ₁ , a second coil V ₂ , a first coil W ₁ , and a second coil W ₂ ). The input/output coil 18 according to this embodiment is composed of a three-phase coil. Note that this is an example, and the form of the coil does not determine the number of poles. For example, in the case of 12 poles, each phase of U ₁ , U ₂ , V ₁ , V ₂ , W ₁ , and W ₂ is a coil body with 6 coils in series, or in the case of 8 poles, U ₁ , U ₂ , V ₁ , V ₂ , W ₁ , and W ₂ may all be coil bodies with four coils in series. As described above, the number of poles cannot be determined from the form of the input/output coil 18, and any number of poles may be used as long as the number of poles is even. Between the coils (the first coil _U1 and the second coil _U2 , the first coil _V1 and the second coil _V2 , the first coil _W1 and the second coil _W2 ) that make up each phase, a changeover switch A circuit unit 20 (20U, 20V, 20W) is provided.

The circuit section 20 is composed of two changeover switches (first switch A and second switch B) with one port on the input side and two ports on the output side arranged in parallel. The input port of the first switch A is connected to the first coils U ₁ , V ₁ and W ₁ respectively, and the input port of the second switch B is connected to the first bypass line. The second coils U ₂ , V ₂ and W ₂ are connected to the output side port of the first switch A on the a port side, and the second bypass line is connected to the b port side. Further, the a port side is open (unconnected) to the output side port of the second switch B, and the b port side is connected to branch lines from the second coils U ₂ , V ₂ and W ₂ . ing.

With such a circuit configuration, the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , W ₂ are connected in series by switching the switches constituting the circuit unit 20, or It is possible to switch to parallel connection. Specifically, when both the first switch A and the second switch B are connected to the a port, the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , W ₂ are connected in series. becomes (see FIG. 5). On the other hand, when both the first switch A and the second switch B are connected to the b port, the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , W ₂ are connected in parallel ( See Figure 6). That is, the switching timings of the first switch A and the second switch B are configured to match.

In such switching control, a system in which the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , W ₂ are connected in series (referred to as the first system) provides good torque characteristics. . On the other hand, a system in which the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , W ₂ are connected in parallel (referred to as a second system) has good rotation characteristics. To explain using the torque constant of the motor, the series connection increases the torque constant of the motor and increases torque per current (improves torque characteristics). On the other hand, by connecting the motors in parallel, the torque constant of the motor becomes small and it becomes possible to rotate at high speed (the rotation characteristics are improved). In this embodiment, the purpose of the terminal switching is to change the torque constant. As a result, the rotation characteristics and torque characteristics change, and it is possible to provide an optimum motor for each situation.

FIG. 7 shows the relationship characteristics between the torque and the number of revolutions (TN characteristics) and the relationship characteristics between the torque and current (TI characteristics) of the first system and the second system, respectively. Comparing the second system and the first system, it can be seen that the second system has a high normal rotation range, so that the rising gradient of the power consumption accompanying the improvement of the torque is steep. On the other hand, it can be seen that although the first system can generate high torque in the low rotation range, the maximum rotation speed is only about half that of the second system.

By using the first system in the low speed range and the second system in the high speed range based on the characteristics of each system, it is possible to effectively utilize the advantages of each of the two motors. FIG. 8 shows the motor characteristics (TN characteristics and TI characteristics) obtained when switching between the first system and the second system in the rotation range where the maximum torque is 1/2. The motor 10 according to this embodiment, which performs system switching, can generate high torque while suppressing power consumption (current) in the low rotation range. Also, in areas where there is no problem with low torque operation, it is possible to achieve a high rotational speed that cannot be obtained with the first system.

In order to realize such a configuration, switching of the switches (the first switch A and the second switch B) constituting the circuit section 20 must be performed simultaneously in the three phases of the U phase, the V phase, and the W phase. . For this reason, the motor 10 according to the embodiment is provided with a control section 22 that outputs a switching signal to the circuit section 20 . Note that the control unit 22 uses a predetermined rotational speed threshold as a reference, and increases the number of coils connected in series in each phase on the lower rotational speed side than the threshold, and increases the number of coils connected in parallel on the higher rotational speed side. It is preferable to adopt a configuration in which switching is performed as follows. This is because power consumption and generated torque can be balanced, and the width of the usable rotation range can be widened.

When an electric vehicle is constructed by applying the motor 10 having such a configuration to the motive power of a vehicle, the output characteristics of the first system (series) and the second system (parallel) show a tendency as shown in FIG. Become. For this reason, it is possible to divide the system into three zones from the viewpoint of generated torque, required rotation range, and power consumption while switching the system.

That is, the first zone should be applied when output torque is required (roughly 1/2 or more of the maximum torque), such as when starting or climbing a hill (first system: at low speed). In addition, the second zone should be applied when the number of revolutions is relatively low, output torque is unnecessary (roughly less than 1/2 of the maximum torque), and power consumption should be suppressed (for example, during normal driving) (first system : at high speed). Furthermore, the third zone is preferably applied when a high rotation speed is required and output torque is not required (approximately less than 1/2 of the maximum torque), such as during high speed running (second system: high rotation).

[effect]
According to the motor 10 having the characteristics described above, as the power consumption is improved, a predetermined torque (the first coils U ₁ , V ₁ , W ₁ and the second coils U ₂ , V ₂ , It means that high torque can be obtained even at a high rotation speed compared to the high rotation range of the system (first system) in which _W2 is connected in series.

In addition, since the coil does not have an iron core, the self-inductance can be kept small, and the responsiveness from switching by connection switching by the circuit unit 20 to characteristic switching can be improved, and the rotor 16 can be rotated. It is possible to prevent deformation of the stator coil 18 due to anti-torque when rotating. In order to make the stator coil 18 resistant to deformation, a deformation-resistant coil body can be formed by providing a deformation-resistant layer (not shown) or providing individual reinforcing means. good.

As the deformation-resistant layer added to the stator coil 18, a film sheet may be attached to at least one side surface (inner side or outer side) of the stator coil 18 formed in an annular shape. The film sheet is preferably made of fiber reinforced plastic (FRP), carbon fiber reinforced plastic (CFRP), or the like. With such a configuration, even if the capacity of the motor 10 is increased, it is possible to prevent the stator coil 18 from being deformed by the counter torque of the rotor 16 .

When the stator coil 18 is provided with reinforcing means, a ring-shaped reinforcing ring (not shown) made of metal or the like may be arranged at the free end of the ring-shaped stator coil 18 . Furthermore, instead of the reinforcing ring, or together with the reinforcing ring, the above-described coil switching board 24 may be arranged at the proximal end portion or the distal end portion of the stator coil 18 . This is because the stator coil 18 can be reinforced in the same manner as the reinforcing ring.

A coreless motor has no iron core. Therefore, the inductance becomes small. If the inductance is large, it becomes difficult for the current to change. Therefore, if the current is forced to change, a high voltage is generated. When a large current is flowing, if the current is suddenly cut off (for example, if you switch from parallel to series, the current will be cut off at that moment), high voltage will be generated. If this happens, the circuit may be overvoltaged and the circuit elements may be damaged. This is because circuit elements are vulnerable to overvoltage.

For this reason, for motors with large inductance such as cored motors, as a countermeasure, it is necessary to devise additional work such as temporarily turning off the current and replacing it in the work procedure to prevent a large voltage from being generated when switching the circuit. I have no choice. Therefore, when using a cored motor to switch windings, it is necessary to use multiple preventive elements to avoid accidents caused by overvoltages caused by sudden changes in current when switching windings, and the wiring becomes complicated. .

On the other hand, in the motor 10 (coreless motor) configured according to the present embodiment, the overvoltage is only a fraction (eg, 1/20 or less) of that of the cored motor (iron core motor). As a result, extra equipment and work for avoiding accidents are not necessary, and switching between series and parallel can be instantaneously performed only by the circuit section 20 provided on the coil switching board 24 . This is a technique that was first conceived and demonstrated by the inventors of the present application.

In general, when a motor is applied to a vehicle, in the case of a motor with a large inductance such as a cored motor, if the supply current to the motor is cut while a load is applied, resistance acts to stop the rotation of the rotor. As a result, the speed drops and a shock occurs. In contrast, when the motor 10 according to the present invention is employed, it can be said that the shock due to the inductance is less likely to occur.

[Second embodiment]
Next, the configuration of the motor 10 according to the second embodiment will be described with reference to FIGS. 10 to 12. FIG. The motor 10 according to the present embodiment differs in the configuration of the stator coil 18 from that of the motor 10 according to the first embodiment. It should be noted that the configuration of the motor 10 will be described with reference to FIG. 1 for portions having the same function.

The stator coil 18 according to the present embodiment has 3 phases and 12 poles using 4 coils (12 coils in total) for each phase. In the stator coil 18 having such a configuration, the coils constituting each phase (first coil U ₁ , second coil U ₂ , third coil U ₃ , fourth coil U ₄ , first coil V ₁ , (second coil V ₂ , third coil V ₃ , fourth coil V ₄ , first coil W ₁ , second coil W ₂ , third coil W ₃ , fourth coil W ₄ ). (20U ₁ , 20U ₂ , 20U ₃ , 20V ₁ , 20V ₂ , 20V ₃ , 20W ₁ , 20W ₂ , 20W ₃ ) are provided.

As the configuration of the circuit unit 20, the circuit units _20U1 , _20U3 , _20V1 , _20V3 , _20W1 , and _20W3 are the same as the circuit units 20U, 20V, and 20W according to the first embodiment. On the other hand, in the circuit units 20U ₂ , 20V ₂ , and 20W ₂ , the number of input ports and the number of output ports of the second switch B are opposite to those of the first switch A.

In the motor 10 having such a configuration, in each of the U-phase, V-phase, and W-phase, the first switch A and the second switch B are set to the a port for each of the circuit units 20U ₁ to 20W ₃ . 1st coil U ₁ to 4th coil U ₄ , 1st coil V ₁ to 4th coil V ₄ , and 1st coil W ₁ to 4th coil W ₄ are connected in series (this state is called 1 parallel). (refer to FIG. 10).

When the first switch A and the second switch B of the circuit units 20U2, 20V2, and 20W2 are set to the b port from the 1-para state, for example, in the U phase, the first coil _U1 and the second coil _U2 are connected in series. , the third coil _U3 and the third coil _U4 are connected in series, the set of the first coil _U1 and the _second coil U2, and the set of the third coil _U3 and the fourth coil _U4 are connected in parallel. will be connected to Each coil is similarly connected in the V-phase and W-phase (this state is called 2-parallel: see FIG. 11).

Further, in each of the U-phase, V-phase, and W-phase, for the circuit units 20U ₁ to 20W ₃ , when the first switch A and the second switch B are set to port b, the first coil U 1 to the first coil U ₁ to The four coils U ₄ , the first to fourth coils V ₁ to V ₄ , and the first to fourth coils W ₁ to W ₄ are connected in parallel (this state is called 4-parallel: see FIG. 12). .

In the motor 10 configured as described above, a system with more coils connected in series has a higher torque characteristic (paragraph 1 above), and a system with more coils connected in parallel has a higher rotation characteristic (paragraph 4 above). Taking advantage of these characteristics, when the motor 10 is operated by switching the system from 1-parameter to 4-parameter, the torque and rotation speed relationship characteristics (TN characteristics) and the torque and current relationship characteristics (T- I) Characteristics are shown in FIG.

According to FIG. 13, the system can be switched between 1st, 2nd, and 4th rotations as the number of revolutions increases, thereby realizing high-torque operation while keeping the power consumption below a predetermined value. . In addition, by switching between 2-parallel and 4-parallel, it is possible to achieve operation in a high rotation range that cannot be obtained with a 1-parallel. For example, when the motor 10 having such a configuration is applied to the power for propulsion of an electric vehicle, the 4th, 2nd, and 1st gears function as transmission mechanisms corresponding to top gear, second gear, and low gear, respectively. becomes.

[effect]
Even with the motor 10 having such a configuration, it is possible to obtain a predetermined torque even in a high speed range, like the motor 10 according to the first embodiment.
Furthermore, by increasing the number of coils and circuit units, the degree of freedom in switching characteristics can be improved.

[Operation switching]
A specific example of operation switching when the motor 10 according to the present embodiment is applied to an electric vehicle will be described with reference to FIGS. 14 to 16. FIG. It should be noted that this embodiment corresponds to an embodiment of operation switching in electric vehicles in general, such as wheelchairs, motorcycles, electric bicycles, so-called senior cars, automobiles, and AGVs (automatic guided vehicles). It can also be viewed in common with the changes in rotational speed and load in, etc.

As can be seen from FIG. 14, at the start (=when the vehicle starts), the rotation is low and initial torque is required to move the vehicle. ). After starting the vehicle, for example, when the rotation speed of the motor 10 reaches 700 rpm (equivalent to 30 km/h), the mode is switched from L to 2 parallel. In this example, the connection is switched according to the number of revolutions of the motor 10 . For this reason, when the vehicle speed is further increased and the rotation speed of the motor 10 reaches 1400 rpm (equivalent to 60 km/h), for example, it switches to 4 para.

If the vehicle speed is further increased and the vehicle speed is 100 km/h (for example, the number of revolutions of the motor 10 is 2000 rpm) while maintaining 4 paras, the load on the motor 10 increases when the vehicle enters a slight uphill slope (inclination angle α). As a result, the number of revolutions decreases and the speed decreases. For example, when the rotation speed drops to about 1167 rpm (equivalent to 50 km/h: 5/6 of 1400 rpm), it switches to 2 parallel.

Furthermore, when the vehicle enters a steep slope (inclination angle β) from a slightly uphill slope, the load on the motor 10 further increases, the number of revolutions decreases, and the speed drops. For example, when the rotation speed drops to about 467 rpm (equivalent to 20 km/h: 2/3 of 700 rpm), it switches to series (1 parallel: L). It should be noted that the setting of 50 km/h (1167 rpm), 20 km/h (467 rpm), etc. when traveling on a slope corresponds to the blur width of hysteresis.

When running on a slope, the vehicle gradually accelerates, and when it reaches about 30 km/h (700 rpm) near a flat road, the connection type of the motor 10 is switched to 2-parallel. In addition, when the vehicle is further accelerated to 60 km/h (1400 rpm) on a flat road, it becomes 4 para, and can be accelerated to about 100 km/h (2000 rpm). Up to this point, as the rotation speed of the motor increases, control is performed to switch the connection type of the coil .

On the other hand, when entering a downward slope (for example, a steep slope with an inclination angle γ), the circuit for switching the connection type of the coil is switched according to a command signal from the passenger, and braking (=regeneration) is performed by the rotational resistance of the motor 10. Braking: Control to apply so-called engine braking. For example, on a steep slope, the speed is gradually reduced to about 60 km/h (1400 rpm) in the 4-para state. After that, when the downhill becomes gentle (for example, the inclination angle θ), the speed is reduced further by switching to 2-parallel. By gradually reducing the speed (rotational speed) in this way, it is possible to prevent a sudden load from being applied to the motor 10 .

When the vehicle speed drops to about 30 km/h (700 rpm) on a gentle downhill, the connection type of the motor 10 is switched to 1-parallel (series), and the road is flat. It should be noted that on a downhill, the power supply can be charged by applying regenerative braking as described above.

The above flow is shown in FIGS. 15 and 16 as switching between high speed (Top: T), medium speed (Second: S), and low speed (Low: L), and will be described below.

First, when the vehicle starts on flat ground and the speed is in the range of 0-20 km/h, it runs in L, and when it reaches 20 km/h, it switches to S, and when it reaches 60 km/h, it switches to T, and in T it reaches 100 km/h. In section A shown in FIG. 15, the accelerator is fully opened (fully opened), and the circuit for detecting the rotational speed of the motor 10 and automatically switching the coil connection type is switched. In this section, the rotation speed of the motor 10 increases as the vehicle accelerates, while the accelerator signal (manual accelerator signal) input by the driver is output as a signal for increasing the rotation speed to MAX. Therefore, the manual accelerator signal becomes higher than the rotation speed of the motor 10 .

Next, when entering an uphill, the speed drops to about 60 km/h , and the circuit for switching the connection type of the coil switches to S, and then maintains the S state even when entering a steeper slope. In this section (section B' in FIG. 15), control (current control) is performed based on the degree of opening of the accelerator, instead of controlling the circuit for switching the connection type of the coil according to the number of revolutions (speed) of the motor. Then, when it goes up the slope and enters the flat ground (when it passes through section B'), it switches to rotation speed control (speed control), and the circuit for switching the coil connection type switches to L to accelerate the vehicle. As the speed (rotational speed) rises, it switches to S, and then switches to T. Here, the top speed at T reaches about 100 km/h. In section B shown in FIG. 15, priority is given to circuit switching control for switching the connection type of the coil according to the degree of opening of the accelerator. Therefore, when the rotational speed (speed) of the motor 10 is lower than the support based on the accelerator opening, the circuit for switching the coil connection type is switched by the current instruction based on the accelerator opening. . That is, in section B', the number of rotations of the motor 10 decreases as the vehicle speed decreases, but the circuit for automatically switching the coil connection type is switched according to the current value in order to maintain the vehicle speed at 60 km/h. As described above, in section B, the state in which the number of rotations (speed) of the motor 10 relative to the degree of opening of the accelerator is low continues. Therefore, the manual accelerator signal is also greater than the rotation speed of the motor 10 in the section B as well.

Next, when going downhill from a flat road, even if it is a steep downhill, it starts to go down in the T state at first, changes to S after the slope becomes gentle, and then changes to L when it reaches the level ground. be. In this section C, the number of revolutions (speed) of the motor 10 becomes greater than the accelerator opening (current command) due to gravitational acceleration. Therefore, the circuit for switching the connection type of the coil is switched according to the driver's adjustment of the accelerator opening (accelerator instruction).

Next, FIG. 16 illustrates another aspect of the operation switching pattern. In the example shown in FIG. 16, the top gear is selected in the range from level ground to uphill with a small inclination angle. After that, when the inclination of the uphill becomes a medium angle, the gear is switched to the second gear, and when the inclination becomes large, the gear is switched to the low gear. Then, when the inclination angle becomes a gentle uphill state, the vehicle is switched to the second gear again, and when the terrain becomes flat after climbing a plateau, the vehicle is switched to the top gear.

In general, there is a trade-off between increasing the torque of the motor and increasing the maximum rotation speed of the motor. If you try to increase , the maximum torque will decrease. In the past, attempts were made to increase the rotation speed by increasing the voltage of the power source and to increase the torque by increasing the current of the power source, but these control methods have safety issues and technical limitations. Therefore, the inventors of the present invention considered automatic switching between motors having different characteristics electrically, and solved this conventional problem. By taking such measures, the motor itself is one, and by enabling multistage circuit switching such as Low gear, 2'nd gear, and Top gear, a plurality of motors with different characteristics It is possible to obtain the same effect as switching automatically.

Here, the Low gear has high torque and low rotational speed, and can generate high torque with a small current. A high voltage is required to increase the rotation speed in the low gear stage, but since the operation is performed at a low rotation speed in the low gear stage, a high voltage is not required. In addition, the 2'nd gear provides medium torque and medium rotation speed, and the top gear provides low torque and high rotation speed (high speed rotation is possible with low voltage). A large current is required to obtain a high torque in the top gear, but a large current is not required in the top gear stage because the operation is performed with a low torque.

In this way, by providing the motor with a switching function by means of a circuit for switching the coil connection type , a single motor can handle both high torque and high speed rotation. Therefore, it is not necessary to increase the voltage output and increase the current output of the driver. Therefore, the overload on the motor is reduced, and a sudden rise in the temperature of the motor can be suppressed.

As described above, in the motor 10 according to the present invention, it is possible to switch characteristics in three or more steps by switching connection between a series Lo state and a plurality of parallel (for example, second and third) connections. That is, by selecting the position and number of coils for each phase, the connection form can be switched between a serial form and a parallel form of a plurality of patterns. For this reason, when applied to electric vehicles such as bicycles, motorcycles, so-called senior cars, wheelchairs, and automobiles, it is possible to switch gears in multiple stages without interposing mechanical gears ( using a circuit for switching the connection type of the coil). switching) is possible.

The total number of coils for each phase is divided according to the number of switching stages (series (= 1 parallel), multiple patterns in parallel). It is desirable to prevent For example, if the total number of coils is 24, then 24 coils are divided for series (1 parallel) and 12 coils for 2 parallel. Similarly, 8 coils for 3 para, 6 coils for 4 para, and 4 coils for 6 para can be equally divided. Further, the number of divisions is increased so that 3 coils are used for 8 parallels, 2 coils are used for 12 parallels, and 1 coil is used for 24 parallels. By equally dividing the coils in this manner, there is no difference in the number of parallel coils in each phase, so that no circulating current is generated. Therefore, it is possible to suppress heat generation due to the generation of circulating current, and to avoid an increase in waste (loss) in energy (power) efficiency.

By the way, the circuits shown in the above embodiments can be incorporated in the motor 10. FIG. Especially when the circuit is housed in the motor, the internal space unique to the coreless motor can be effectively utilized. Furthermore, the motor 10 according to the present invention can maintain its function as a rotary electric machine without necessarily providing the rotating shaft 14 . This configuration is possible because the rotating shaft 14 and the rotor 16 are not connected by a core, and can be realized, for example, by directly connecting the rotating shaft of the input/output device to the rotor. With such a configuration, the inside of the motor 10 has a hollow structure, so that the internal space can be used more effectively.

Further, in the above-described embodiment, it has been described that switching is performed mainly by a circuit for switching the connection type of the coil based on the number of revolutions of the motor 10 . However, when the motor 10 according to the present invention is applied to the power for propulsion of an electric vehicle, the vehicle speed (vehicle speed) of the electric vehicle to be applied is detected, and the coil connection type is switched based on the detected vehicle speed value. It is also possible to perform switching by a circuit for the purpose . The vehicle speed may be detected using a sensor (not shown) or the like, and various conventional (known) methods can be used.

[Application form]
In each of the above-described embodiments, a circuit unit is provided for each single coil. However, the number of coils arranged between circuit sections is not limited to one. For example, by varying the number of coils arranged between circuit sections and devising the layout of the circuit sections, it is possible to divide the number of coils connected in series when connecting coils in parallel. , the width of the characteristic change can be widened by the combination of the coils connected in series and the coils connected in parallel.

For example, in a motor 10 having a stator coil 18 configured as shown in FIG. 17, each phase (U phase, V phase, W phase) has 12 coils (first to twelfth coils: U ₁ -W ₁₂ ). are arranged, and five circuit units (20U ₁ -20W ₅ ) are provided. As an example, the circuit portions 20U ₁ -20U ₅ ) in the U phase are between coils U ₃ and U ₄ , between coils U ₄ and U 5 , between coils U 6 and U ₇ , between coils U ₆ and U ₇ , and between coils U _{8 .} and coil _U9 , and between coil _U9 and coil _U10 . Note that the layout of the circuit portions (20V ₁ -20W ₅ ) is the same for the V phase and the W phase.

The circuit units (20U ₁ -20W ₅ ) are provided with ports a1, b1, a2, b2, c1 and c2, respectively. In the circuit unit (20U ₁ -20W ₅ ) having such ports, ports a1 and b1 are switchable with port c1, and ports a2 and b2 are switchable with port c2. , and both are configured to be switched at the same time.

Next, the relationship between the switching of the connection form of the stator coil 18 and the switching of the circuit units (20U ₁ -20W ₅ ) in this embodiment will be described. Since the circuit units (20U ₁ to 20W ₅ ) corresponding to each phase are switched at the same time, the circuit units 20U ₁ , 20V ₁ and 20W ₁ are referred to as the circuit unit 20X 1 and the circuit units 20X 1 and 20W ₁ in the following description. 20U ₂ , 20V ₂ , and 20W ₂ are the circuit portion 20X ₂ , the circuit portions 20U ₃ , 20V ₃ , and 20W ₃ are the circuit portion 20X ₃ , the circuit portions 20U ₄ , 20V ₄ , and 20W ₄ are the circuit portion 20X ₄ , and the circuit portion 20U ₅ , 20V ₅ and 20W ₅ will be referred to as a circuit section 20X ₅ for explanation.

In the motor of this embodiment, in the case of 1-para (series connection), switching is set so that the a port and the c port are connected in all the circuit units 20X ₁ to 20X ₅ . In the case of 2-parallel, only the circuit section _20X3 is switched so that the b port and the c port are connected. Also, in the case of 3-parameter, switching setting is made so that the b port and the c port of the circuit section _20X2 and the circuit section _20X4 are connected. Furthermore, in the case of 4-parameter, switching setting is made so that the b port and the c port of the circuit portions 20X ₁ and 20X ₃ and the circuit portion 20X ₅ are connected.

If the coils constituting each phase are arranged in an annular shape, the form shown in FIG. 18 is obtained. In the example shown in FIG. 18, the boundary between the coil U ₁ and the coil U ₁₂ is used as the power input/output terminal, and the coils U ₁ to _{U 12} are arranged in an annular (cylindrical) shape around the right. In the coils arranged in this manner, when the above two paragraphs are executed, the coil is divided (halved) in the circuit unit _20U3 , and the coils U ₁ to U ₆ and the coils U ₇ to U ₁₂ are connected in series. The Rukoto. Further, when the above three paras are executed, the coils are divided (divided into three equal parts) by the circuit units 20U ₂ and 20U ₄ , and the coils U ₁ to U ₄ , the coils U ₅ to U ₈ , and the coils U ₉ to U ₁₂ are respectively They are connected in series. Furthermore, when the above four paragraphs are executed, the coils are divided (divided into four equal parts) by the circuit units 20U ₁ , 20U ₃ and 20U ₅ , and the coils U ₁ -U ₃ , U ₄ -U ₆ , U ₇ -U ₉ , U ₁₀ -U ₁₂ are connected in series.
Although FIG. 18 shows the U-phase coil arrangement, the same applies to the V-phase and W-phase.

Also, FIG. 19 shows an example of a 6-stage switching circuit using the present invention. In this example, three phases of U, V, and W are used, and 12 coils are used for each phase. Six-stage switching of 12 parallels (2 or more parallel) is possible. In the example shown in FIG. 19, the combination of relays as shown in the figure is used for the sake of simplicity of explanation. You can put it together. This is because it is possible to reduce the size and weight of the motor 10 itself and to simplify the internal wiring by integrating the circuit device using semiconductor elements. In the figure, a1, a2, b1, b2, c1, and c2 are ports (contacts), Lu1 to Lu12, Lv1 to Lv12, Lw1 to Lw12 are coils, Ku1 to Ku11, Kv1 to Kv11, Kw1 to Kw11 are circuit parts (relays ).

The ports c1 and c2 in the circuit section are switched at the same time, and when the port c1 is connected to the port a1, the port c2 is connected to the port a2 at the same time. In such a connection form, the coils arranged on both sides of the circuit section are connected in series. In the circuit section, the port a2 is an unused terminal (unconnected). On the other hand, when port c1 is connected to port b1, port c2 is simultaneously connected to port b2. In such a connection form, the coils arranged on both sides of the circuit section are connected in parallel. If there are 11 such circuit units, depending on which position of the circuit unit a or b is selected, 1 parallel (1 parallel is serial), 2 parallel, 2 parallel, as shown in the table shown in FIG. 3 para, 4 para, 6 para, 12 para can be selected. Note that x in Kx1 to Kx11 in the table indicates u, v, and w (for example, Kx1 of the U phase becomes Ku1).

A plurality of phases (three phases in the above explanation) are required to rotate the motor, but the switching method shown in the table is the same for each phase. Note that the switching operation may be automatic or manual, and the essence of this embodiment is that it is possible to switch in a plurality of stages other than series. For the switching operation, for example, the number of stages is selected by the gear switching operation means 30 shown in FIG. .

[Other than 3-phase: 2-phase example and 5-phase example]
In the above embodiment, the stator coil 18 has been shown and explained as being composed of three phases of U, V and W. However, the motor 10 according to the present invention is characterized in that it is possible to switch circuits in multiple stages between series and parallel. Therefore, the stator coil 18 is not limited to three phases as long as it is composed of a plurality of phases.

FIGS. 21 to 23 show examples in which the stator coil 18 is composed of two phases. In the circuit diagram of FIG. 21, when the circuit section 20 is tilted toward the solid line side, the coils forming the stator coil 18 are connected in series, and when tilted toward the broken line side, the coils are connected in parallel. 22 and 23 are explanatory diagrams schematically showing the configuration of the stator coil 18. FIG. In both figures, two types of coils, a solid line and a broken line, are drawn to indicate two phases. In addition, mountain-shaped portions near the permanent magnet 16a indicated by S and N on the upper side of the drawing represent coils forming poles. 22 shows a state in which each coil is connected in series, and FIG. 23 shows a state in which each coil is connected in parallel.

Next, FIGS. 24 to 26 show examples in which the stator coil 18 is composed of five phases. In the circuit diagram of FIG. 24, the coils are connected in series when the circuit section 20 is tilted toward the solid line side, and the coils are connected in parallel when the circuit portion 20 is tilted toward the broken line side. 25 and 26 are explanatory diagrams schematically showing the configuration of the stator coil 18. FIG. In both figures, coils are represented by five types of lines to indicate five phases. In addition, mountain-shaped portions near the permanent magnet 16a indicated by S and N on the upper side of the drawing represent coils forming poles. 25 shows a state in which each coil is connected in series, and FIG. 26 shows a state in which each coil is connected in parallel.

[Short prevention in switching circuit (circuit unit 20)]
If switching between series and parallel is by a mechanical selection action, no short circuit will occur. However, if a switching element or the like is used without relying on a mechanical selection mechanism, there is a possibility that an instantaneous short-circuit may occur depending on the timing, so countermeasures must be taken. As one of countermeasures, there is a method using a clock. Specifically, the serial gate and the parallel gate should be prevented from being ON (Hi) at the same time.

FIG. 27 and FIG. 28 show the relationship between the clock and the command signal, and the configuration example of the control section for the circuit section when specific countermeasures are taken. When a command signal from the gear switching operation means 30 is input to the controller 31, it is input as a command signal Sin (serial in) from the controller 31 to the shift register 32. FIG. Regarding the switching of each coil in the series type and one or more parallel types, if it is a relay circuit, it is difficult for a short circuit to occur. It is desirable to provide an OFF period).

When the command signal Sin is input, the shift register 32 outputs command signals from terminals Q0, Q1, and Q2, respectively. At this time, in the shift register 32, the output from each terminal (Q0, Q1, Q2) is adjusted by the action of the clock signal clk so as to produce a shift as shown in FIG. Specifically, Q0 becomes L when Sin is L (Lo, hereinafter the same) and clk rises, and Q0 becomes H when Sin is H (Hi, hereinafter the same) and clk rises. On the other hand, in other cases, that is, when Sin does not change, the signal state remains L or H regardless of the rise of clk. Q1 is changed based on the signal of Q0. Specifically, when Q0 is L and clk rises, it becomes L, and when Q0 is H and clk rises, Q1 becomes H. Then, if there is no change in the signal of Q0, the previous state, that is, the L or H state is maintained. Q2 is changed based on the signal of Q1. Specifically, when Q1 is L and clk rises, it becomes L, and when Q1 is H and clk rises, Q2 becomes H. When there is no change in the signal of Q1, the previous state, ie, the L or H state, is maintained, as is the case with Q1.

Outputs from Q0 and Q2 are input to the NOR element 33, and a command signal is output as EN (XNOR: exclusive NOR). In the NOR element 33, the output of the command signal is permitted when the signals of Q0 and Q2 match, and the output of the command signal is not permitted when the two signals do not match. Specifically, when the command signal output from Q0 is L and the output from Q2 is also L, the gate becomes H and the output of the command signal is permitted. Similarly, when the output from Q0 is H and the output from Q2 is also Hde, the gate becomes H and the output of the command signal is permitted. On the other hand, when the command signal output from Q0 is L and the output from Q2 is H, or when the output from Q0 is H and the output from Q2 is L, the gate becomes L and the command signal is output. No output allowed.

The command signal output from Q1 in the shift register 32 is input to the AND element 35 via the NOT element 34 and directly to the AND element 36 as well. Since the output signal from the NOT element 34 is the opposite of the input signal (when the command signal output from Q1 is L, the output from the NOT element 34 is H, and the command signal from Q1 is H). If there is, the output from the NOT element 34 is L), and the opposite command signals are input to the AND elements 35 and 36 as the command signals from Q1.

The AND elements 35 and 36 output H as the command signal only when the command signal from Q1 and the output signal from the NOR element 33 become H at the same time. As described above, opposite signals (L or H) are input to the AND element 35 and the AND element 36 as command signals from Q1, so that both do not output H command signals at the same time. Also, since there is a difference in the switching timing of the command signals from Q0 and Q1 and Q2 in the shift register 32, the switching timing of the output signal from the NOR element 33 and the switching timing of the command signal from Q1 coincide. There is nothing to do. Therefore, there is no possibility that the switching timings of the command signals of the AND element 35 and the AND element 36 will match.

Outputs from the AND element 35 and the AND element 36 are input to blocks 37, 38, and 39, respectively, which constitute circuits of respective phases. A block 37 indicates a U-phase block, a block 38 indicates a V-phase block, and a block 39 indicates a W-phase block. In blocks 37, 38, and 39, G1s to which the command signal output from the AND element 35 is input is the input terminal of the switching signal to the gate serial (serial side). G1p to which a signal is input is an input terminal of a switching signal to gate parallel (parallel side). As described above, the command signals from the AND element 35 and the AND element 36 do not match, and the switching timing of L and H also deviates. Therefore, as shown in FIG. 27, there is no timing when G1s and G1p are turned ON (Hi) at the same time, and no short circuit occurs. The number "1" in G1s and G1p indicates the number of each circuit section, and the terminals at Kx11 in the circuit section in FIG. 20 can be indicated as G11s and G11p, respectively.

FIG. 29 shows an example of a circuit diagram forming a block. The example shown in FIG. 29 is an example of a circuit diagram of a block that configures the U phase, but the blocks that configure the V phase and W phase also have the same configuration. For example, Lu1h is Lv1h for the V phase, Lw1h for the W phase, and Lv2h and Lw2h for Lu2h. Also, Lu1l becomes Lv1l and Lw1l, and Vu becomes Vv and Vw, respectively. In the example shown in FIG. 29, switching elements and FET (Field Effect Transistor) elements 40 corresponding to the circuit section are shown. There is no limit.

A rotary electric machine having a circuit portion as described above can also be applied to a motor 50 used underwater as shown in FIGS. When applied to the motor 50 for underwater use, the rotor 16 and the stator coil 18 described above are housed in a housing 52 having a defined propelling direction. As shown in FIG. 30, the forward direction of the housing 52 is defined as the forward direction of the housing 52, which has a so-called nosecone with a slightly rounded tip. Moreover, it is set as the structure which makes the rotating shaft 14 protrude in the propulsion direction rear side.

In the motor 50 having such a configuration, which is used underwater, it is preferable to adopt a configuration in which cooling water is introduced into the housing 52 . The cooling water introduced into the housing 52 circulates within the housing 52 due to the rotation of the blades 14 a provided on the rotating shaft 14 . Thereby, the cooling effect of the cooling water can be enhanced. Reference numeral 54 is a hole through which a cable or the like is passed.

Also, as an example of application to the motor 50, an autonomous propulsion type as shown in FIG. 31 may be used. Note that even with the motor 50 of the autonomous propulsion type, there is no change in the configuration in which the rotor 16 , the stator coil 18 and the coil switching board 24 are arranged inside the housing 52 . Here, as in the examples shown in FIGS. 30 and 31, when the rotating shaft 14 does not protrude forward in the propelling direction, the coil switching board 24 does not need to be provided with an opening through which the rotating shaft 14 is inserted. . Therefore, the coil switching board 24 can be made into a disc shape as shown in FIG. As shown in FIG. 32, the disk type mentioned here also includes the one in which a notch 26 is provided on a part of the plate surface as necessary. This is because the cutouts and through-holes provided in a part of the substrate for inserting wiring or the like are provided after determining the plate surface shape of the entire substrate. Further, in the example shown in FIG. 31, the cooling blades 14a are not provided inside the housing 52, but needless to say, they may be provided.

The motor 50 shown in FIG. 31 has a screw 56 for generating propulsive force outside the housing 52, and a skeg 52a is provided at the bottom of the housing 52. As shown in FIG. Here, the skeg 52a serves as a rudder during propulsion.

Furthermore, when applying a rotary electric machine to the motor 50, it can be configured as shown in FIG. The motor 50 shown in FIG. 33 has a wind tunnel-shaped housing 52 and a housing 53 which are arranged in a double structure. It is configured.

When the motor 50 used in water is configured as described above, the constricted portion of the housing 52 is used as the discharge port 55 to discharge water vapor generated by the heat of the stator coil 18 evaporating the cooling water. The steam discharged from the discharge port 55 accelerates the flow of running water taken in from the water intake port 53a by the screw 56 . This makes it possible to improve the driving force and reduce the torque for rotating the screw 56 .

Reference Signs List 10 Motor 12 Housing 12a Bearing 13 Stator 13a Bearing 14 Rotary shaft 14a Blade 16 Rotor 16a ……Permanent magnet 16b……Inner yoke 16c……Outer yoke 17……Supporting member 18……Stator coil 18a……Conductive wire 18b……Enamel layer 18c…… . ……Gear switching operation means 31 ……Controller 32 ……Shift register 33 ……NOR element 34 ……NOT element 35 ……AND element 36 ……AND element 37 . …… U-phase block 38 …… V-phase block 39 …… W-phase block 50 …… Motor 52 …… Housing 52a …… Skeg vertical stabilizer 53 …… Housing , 55 ..... discharge port, 56 ..... screw, U1 ..... first coil, U2 ..... second coil, U3 ..... third coil, U4 ..... fourth coil, V1 ..... 1st coil, V2......2nd coil, V3......3rd coil, V4......4th coil, W1......1st coil, W2......2nd coil, W3......3rd Coil, W4 …… 4th coil.

Claims (4)

A housing, a non-rotating stator coil configured to form a cylindrical shape with a wire rod and supported in a cantilever manner, and a rotor provided with permanent magnets spaced apart from the stator coil and positioned on the opposite surface of the stator coil. , a coreless motor having
The stator coil consists of a plurality of phases, each phase consists of a plurality of coils,
Equipped with a circuit section that can switch the connection format of the coils that make up each phase between a series format and multiple parallel formats,
The circuit portion is housed in the housing, and the circuit portion is composed of a disc-shaped substrate and is arranged close to the end portion of the stator coil and parallel to the end portion of the stator coil. consists of semiconductor elements ,
The stator coil has a deformation-resistant coil body with a deformation-resistant layer provided on at least one of the inner side and the outer side of the stator coil, or a circular reinforcing ring made of metal at the free end. A motor, characterized in that it is a deformation-resistant coil body made of steel. A housing, a non-rotating stator coil configured to form a cylindrical shape with a wire rod and supported in a cantilever manner, and a rotor provided with permanent magnets spaced apart from the stator coil and positioned on the opposite surface of the stator coil. , a coreless motor having
The stator coil consists of a plurality of phases, each phase consists of a plurality of coils,
Equipped with a circuit section that can switch the connection format of the coils that make up each phase between a series format and multiple parallel formats,
The circuit portion is housed in the housing, and the circuit portion is composed of a disc-shaped substrate and is arranged close to the end portion of the stator coil and parallel to the end portion of the stator coil. is composed of a semiconductor element , and the semiconductor element has a period set to be OFF both before and after coil switching,
The stator coil has a deformation-resistant coil body with a deformation-resistant layer provided on at least one of the inner side and the outer side of the stator coil, or a circular reinforcing ring made of metal at the free end. A motor, characterized in that it is a deformation-resistant coil body made of steel. 3. The motor according to claim 1 or 2,
A rotating shaft that rotates in synchronization with the rotor,
A motor according to claim 1, wherein the rotary shaft is provided with blades at a portion located within the housing. Using the motor according to claim 1 or 2 submerged in water,
The housing in which the stator coil and the rotor are housed is characterized in that the direction of propulsion is determined, and the extension part of the rotating shaft protrudes outside the housing from the side opposite to the direction of propulsion. motor.

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