JP2013019518A - Actuator, band brake device, and motor control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an actuator, a band brake device, and a motor control method, that can easily know the timing when braking force is generated.SOLUTION: The actuator calculates the displacement amount of a driven mechanism based on an electric current ripple component Ir in at least one of the time periods that are: a free-running time period S being a time period from a time point at which the driven mechanism starts displacing and an elastic deforming member starts braking of a rotator, to a time point at which the driven mechanism stops displacing and the braking force generation is completed; and a releasing time period W being a time period from a time point at which the driven mechanism starts displacing so that the braking of the elastic deforming member is released from a state that the rotation of the rotator is stopped by the braking by the elastic deforming member and the rotator starts rotation, to a time point at which the driven mechanism stops displacing.

Description

  The present invention relates to an actuator, a band brake device, and a motor control method.

  Patent Document 1 describes a technique for preventing deterioration of the shift shock and deterioration of the durability of the friction engagement element by controlling to optimize the engagement hydraulic pressure of the friction engagement element. In this technique, an actual shift time of an automatic transmission is detected by a shift time detecting means, and the detection result is compared with a standard set time by a comparing means.

  Patent Document 2 describes a technique for smoothening the rise of the brake engagement pressure and the brake release pressure (direct clutch operating pressure). In this technique, instead of the solenoid valve, a groove is provided along the longitudinal direction of the outer peripheral surface of the operating rod.

  Patent Document 3 describes a technique for suppressing a shift shock due to an overshoot of a signal pressure in a shift control device for an automatic transmission that drives a band brake servo by an accumulator valve.

JP 62-067354 A Japanese Patent Laid-Open No. 7-305736 Japanese Patent Laid-Open No. 10-288254

  The techniques described in Patent Documents 1 to 3 are all related to hydraulically controlled actuators. Further, in the technique disclosed in Patent Document 1, when the control is performed only by the control based on the standard setting time, the fact that the rising of the engagement varies is not taken into consideration. In contrast to the techniques described in Patent Documents 1 to 3, there is an electric actuator technique that does not require a hydraulic accumulator or the like.

  For example, in the electric actuator, there is a possibility that the rotation of the rotor of the electric motor for the inertia causes the driven mechanism to be driven with a command load or more, or the driven mechanism struggles. For this reason, it is desired to easily grasp the timing at which the elastic deformation member such as a brake band generates a braking force for braking the brake drum as a rotating body.

  The present invention has been made in view of the above, and an object thereof is to provide an actuator, a band brake device, and a motor control method capable of easily grasping the timing at which a braking force is generated.

  In order to solve the above-described problems and achieve the object, an actuator according to the present invention controls the displacement of a driven mechanism that applies a load to the elastic deformation member in order to elastically deform the elastic deformation member that brakes the rotating body. A motor, a linear motion mechanism that converts rotational motion from the output shaft of the motor into linear motion, and applies displacement generated by the linear motion to the driven mechanism, and current supplied to the motor is detected. Current detector, the amount of displacement of the driven mechanism from when the elastic deformation member starts braking the rotating body to when the braking force is generated, and the rotation of the rotating body by the braking of the elastic deformation member. When the driven mechanism is displaced so as to release the braking of the elastically deformable member from the stopped state, and the driven mechanism changes after the rotating body rotates. Characterized in that it comprises a quantity, and a control unit for calculating the current ripple component extracted displacement amount of at least one of said driven mechanism from said current detector among the.

  With this structure, the displacement amount of the driven mechanism can be detected from the current ripple component when the brush of the brushed motor passes through the commutator segment (commutator piece). For this reason, it is possible to easily grasp the timing at which the braking force is generated. For example, it is possible to perform motor control to alleviate a shock of braking force at the grasped timing. Further, due to the above-described structure, based on the current ripple component when the brush of the brushed motor passes through the commutator segment, the rotating body that has stopped rotating is released from the braking of the elastic deformation member, and the rotating body rotates. The amount of displacement of the driven mechanism from can also be calculated.

  As a desirable aspect of the present invention, an armature core connected to the output shaft, an exciting coil wound around the armature core, a permanent magnet that is magnetized and changes in position relative to the armature core. A member, and a brake coil that is wound around the armature core and connected in an annular shape so as to form a closed circuit, and a force in a direction opposite to the rotation direction of the armature core that rotates by energization of the excitation coil, It is preferable to give to the armature core. With this structure, rotation of the output shaft due to inertia is suppressed early. Further, an increase in the inertial load of the driven mechanism due to the rotation of the rotor can be suppressed.

  In order to solve the above-described problems and achieve the object, a band brake device according to the present invention has a linear motion mechanism that converts rotational motion from the output shaft of the motor into linear motion, and an elastically deformable brake band. An actuating rod that is displaced by the linear motion to apply a load and brake the brake drum according to the elastic deformation of the brake band, and a current detector that detects a current supplied to the motor. The current ripple component is extracted from the current detector, and the displacement of the operating rod from when the brake band starts braking the brake drum to when braking force is generated, and the braking by the braking of the brake band. The operation rod changes so that the brake band is released from the state where the drum rotation is stopped. And a control device for calculating a displacement amount of at least one of the operating rods from the current ripple component, and a displacement amount of the operating rod after the brake drum rotates. . With this structure, the timing at which the braking force is generated can be easily grasped, so that the motor control for reducing the shock of the braking force can be performed. Thereby, it is possible to reduce a shift shock or a sense of incongruity given to the driver.

  As a preferred aspect of the present invention, the linear motion mechanism is a ball screw mechanism, and is provided between the output shaft and the screw shaft of the ball screw mechanism, and is transmitted from the output shaft to the screw shaft. It is preferable to further include a reduction gear mechanism for reducing the speed.

  With this structure, by increasing the reduction ratio of the reduction gear mechanism, the friction when the motor is not energized can be made larger than the braking force at which the brake band holds the brake drum in a stopped state. For this reason, the motor does not reversely rotate due to the reaction force applied from the brake band to the operating rod. And an actuator can hold | maintain the stop state of a rotation, a brake band stopping rotation of a brake drum, without continuing energizing a motor. As a result, it is possible to reduce the electric power of the motor that holds the braking force with which the brake band holds the brake drum in a stopped state of rotation. Further, the ball screw mechanism has high transmission efficiency, and can efficiently convert rotation as linear motion. Even when the ball screw mechanism is used, it is possible to maintain the state in which the brake band stops the rotation of the brake drum by increasing the reduction ratio of the reduction gear mechanism.

  In order to solve the above-described problems and achieve the object, the motor control method of the present invention is a motor that displaces a driven mechanism that applies a load to the elastic deformation member in order to elastically deform the elastic deformation member that brakes the rotating body. In which the driven mechanism is displaced from when the elastic deformation member starts braking the rotating body to when a braking force is generated, or the elastic deformation member The driven mechanism is displaced so as to release the braking of the elastic deformation member from the state where the rotation of the rotating body is stopped by the braking, and the driven mechanism is displaced after the rotating body is rotated. Detecting a release section that is a section, and detecting a current supplied to the motor in the detected idle section or release section, and extracting a current ripple component from the detected current. And a step of integrating the current ripple component as the pulse, characterized in that it comprises the steps of: performing an operation of the integrated value of the pulse to the displacement amount of the driven mechanism.

  By this method, the displacement amount of the driven mechanism can be detected from the current ripple component when the brush of the brushed motor passes through the commutator segment. For this reason, it is possible to easily grasp the timing at which the braking force is generated. For example, it is possible to perform motor control to alleviate a shock of braking force at the grasped timing. Also, with this method, based on the current ripple component when the brush of the brush motor passes through the commutator segment, the rotating body that has stopped rotating is released from the braking of the elastic deformation member and the rotating body rotates. It is also possible to calculate the displacement amount of the driven mechanism.

  According to the present invention, it is possible to provide an actuator, a band brake device, and a motor control method that can easily grasp the timing at which a braking force is generated.

1-1 is a schematic diagram of a band brake device according to the present embodiment. FIG. 1-2 is a schematic diagram of a band brake device according to the present embodiment. 1-3 is a schematic diagram of a band brake device according to the present embodiment. FIG. 2 is an explanatory diagram illustrating load characteristics of the band brake device. FIG. 3 is a configuration diagram of the actuator according to the present embodiment. FIG. 4 is an explanatory diagram for explaining the rotor of the motor. FIG. 5 is an explanatory view illustrating the relationship between the rotor and the stator of the motor. FIG. 6 is an explanatory diagram illustrating the relationship between the commutator and the brush of the motor according to the present embodiment. FIG. 7 is an explanatory diagram for explaining the operation of the motor according to the present embodiment. FIG. 8 is an explanatory diagram for explaining the operation of the motor according to the present embodiment. FIG. 9 is an explanatory diagram for explaining the winding of the exciting coil of the motor according to the present embodiment. FIG. 10 is an explanatory diagram illustrating windings of a brake coil of the motor according to the present embodiment. FIG. 11 is a block diagram illustrating a motor control device according to the present embodiment. FIG. 12 is an explanatory diagram for explaining the operation of the actuator according to the present embodiment in relation to the motor current and time. FIG. 13 is a block diagram illustrating a control block of the actuator. FIG. 14 is a flowchart for explaining the control procedure of the actuator.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

  In general, an automatic transmission includes a torque converter as a fluid coupling and an auxiliary transmission including a planetary gear unit. In the auxiliary transmission, a clutch and a brake are used to select a combination of rotating gears in the planetary gear unit and change the gear ratio. A band brake device is used as this brake.

<Band brake device>
1-1, 1-2, and 1-3 are schematic views of the band brake device according to the present embodiment. The band brake device 110 is attached to a strap 131 surrounding the brake drum 160, a lining 132 positioned on the brake drum 160 side of the strap 131, an anchor bracket 137 attached to one end of the strap 131, and the other end of the strap 131. The brake band 130 including the applied bracket 136, the applying means 151 that contacts the applying bracket 136 and applies a tightening load, and the anchor means 152 that receives and supports the reaction force applied to the anchor bracket 137.

  The brake drum 160 is a rotating body that rotates, for example, in the rotation direction R when the brake is not operated. The brake band 130 is substantially C-shaped. The strap 131 is a strip-shaped plate member made of, for example, steel and capable of elastic deformation. The lining 132 is a friction material, and is fixed to the inside of the strap 131, that is, the brake drum 160 side by adhesion or the like. The apply bracket 136 and the anchor bracket 137 are fixed to both ends of the strap 131 by caulking, welding, rivets or the like.

  The applying means 151 includes, for example, a pin or rod-like member called an operation rod 155 and an actuator 100 to which the operation rod 155 is connected. The actuator 100 can move the operating rod 155 in the arrow X direction or in the direction opposite to the arrow X direction.

  The actuator 100 can move the operating rod shown in FIG. 1-1 to the position of the operating rod shown in FIG. 1-2, for example. Further, the actuator 100 can move, for example, the operating rod 155 shown in FIG. 1-2 to the position of the operating rod 155 shown in FIG. 1-3. Thus, the operating rod 155 whose stroke (displacement amount) has changed applies a load to the applying bracket 136, and the operating rod 155 and the applying bracket 136 move together. Then, the strap 131 bends in conjunction with the moving apply bracket 136. The brake band 130 including the strap 131 that can be elastically deformed is an elastic deformation member. The operating rod 155 can elastically deform the brake band 130 by bending the strap 131.

  The anchor means 152 includes an anchor pin 156 fixed to a reference surface such as a case. The anchor bracket 137 is positioned by the anchor pin 156. Next, the operation of the band brake device 110 will be described with reference to FIGS. 1-1, 1-2, 1-3, and 2. FIG.

  FIG. 2 is an explanatory diagram illustrating load characteristics of the band brake device. In FIG. 2, the load pressed against the brake band 130 from the applying means 151 is shown on the vertical axis, and the stroke of the operating rod 155 is shown on the horizontal axis.

  As shown in FIG. 2, the stroke of the operating rod 155 includes an idle running section S, a deflection section Tb, and a holding section U. In the idling section S, as shown in FIG. 1A, the actuator 100 moves the operating rod 155 toward the actuator 100 side so that the brake band 130 spreads in a larger arc than the outer periphery of the brake drum 160. To do. For this reason, the clearance is maintained (not fastened) between the brake drum 160 and the lining 132. As a result, the brake drum 160 rotates in an idle state, and the brake in the auxiliary transmission becomes inoperative. In addition, the actuator 100 has memorize | stored the starting position J of the idling section S as a reference value (for example, 0) of the stroke of the action | operation rod 155 in the memory | storage means mentioned later. The actuator 100 moves the operating rod 155 in the X direction as shown in FIG. 1-1 from the starting position J of the idle running section S shown in FIG. 2, so that the brake band 130 starts braking the brake drum 160. It will be.

  In the deflection section Tb, the actuator 100 moves the operating rod 155 in the X direction so that the strap 131 of the brake band 130 surrounds the brake drum 160 as shown in FIG. When the apply bracket 136 moves together with the actuating rod 155 in the X direction, the distance between the apply bracket 136 and the anchor bracket 137 becomes short, and the strap 131 bends. For example, the distance between one end and the other end of the brake band 130 is Bxt. As the actuator 100 tightens the brake drum 160 by elastic deformation of the brake band 130, the clearance between the brake drum 160 and the lining 132 decreases. The brake band 130 is deformed into a shape along the brake drum 160. For this reason, the lining 132 is in sliding contact so as to surround the brake drum 160. As a result, the lining 132 of the brake band 130 gives a frictional force to the brake drum 160 in the direction opposite to the rotational direction R.

  A state in which a tightening force for tightening the brake drum 160 is generated by the frictional force of the brake band 130 is referred to as engagement. The deflection section Tb is a section in which the operating rod 115 is displaced from when the brake band 130 generates a frictional force that brakes the brake drum 160 until the brake band 130 stops the rotation of the brake drum 160 by tightening the brake drum 160. It is. That is, the deflection section Tb is a section from when the brake band 130 generates a braking force to the brake drum 160 to when the brake drum 160 stops rotating. The initial braking region P, which is the boundary between the idle running section S and the deflection section Tb, is deformed into a shape close to a perfect circle, for example, so that the brake band 130 surrounds the brake drum 160, and the brake band 130 tightens the brake drum 160. This is a contact start region where braking force starts to be generated. As shown in FIG. 2, the load with which the brake band 130 tightens the brake drum 160 does not increase from the start position J of the idle running section S to the initial braking region P. When the operating rod 155 is moved in the X direction and exceeds the initial braking region P, the brake band 130 starts to generate a frictional force that brakes the brake drum 160. In the band brake device 110, it is easy for the driver to feel the reaction of the braking force generated in the initial braking region P as a shock. For this reason, it is preferable to reduce the speed of the stroke of the actuating rod 155 in the initial braking region P.

  Further, in the holding section U, the actuator 100 further moves the operating rod 155 in the X direction as shown in FIG. For example, the distance between one end and the other end of the brake band 130 is Bxu, which is shorter than Bxt shown in FIG. As shown in FIG. 2, even if the actuator 100 applies a load to the operating rod 155, there is little room for the strap 131 to bend, so the increase in the stroke of the operating rod 155 is small. When the actuator 100 applies a load to the operating rod 155, the lining 132 tightens the brake drum 160, and the rotation of the brake drum 160 stops. In other words, the braking of the brake band 130 causes the brake drum 160 to stop rotating (fastening of the rotating body). In the actuator 100, the operating rod 155 continues to press the apply bracket 136, and the fastening state of the brake drum 160 is maintained.

  At the fastening boundary G, which is the boundary between the deflection section Tb and the holding section U, the brake band 130 tightens the brake drum 160, and the frictional force applied by the lining 132 exceeds the driving force at the contact surface between the brake band 130 and the break drum 160. Then, the brake drum 160 stops rotating. That is, at the fastening boundary G, the rotation of the brake drum 160 stops. In this case, the brake in the auxiliary transmission is activated. As described above, the actuator 100 can brake the rotation of the brake drum 160 by displacing the operating rod 155. Next, the actuator will be described.

<Actuator>
FIG. 3 is a configuration diagram of the actuator according to the present embodiment. The actuator 100 includes a motor 1, a drive shaft 117, a screw shaft 107 as a drive mechanism, a cylindrical nut 115, a first gear 103, a second gear 105, a third gear 106, and a transmission shaft 104. In the housing 101.

  Further, the operating rod 155 described above is connected to the drive shaft 117 to form a driven mechanism. For this reason, the displacement of the drive shaft 117 and the displacement of the operating rod 155 are synchronized.

  The cylindrical housing 101 includes, for example, an aluminum housing main body 101A, a resin cover member 101B assembled to the end surface of the housing by bolts, and the housing main body 101A formed of a metal such as aluminum. Plate 101C.

  The housing 101 preferably fixes the housing main body 101A and the resin cover member 101B via an O-ring 120. As a result, the waterproof property of the housing 101 is enhanced. In addition, a bag hole-shaped motor chamber 101a and a through-hole-shaped screw shaft chamber 101b are formed inside the housing main body 101A.

  The motor 1 is disposed in the motor chamber 101a, and the motor 1 is attached to the housing main body 101A via a positioning plate 101C. With this structure, the output shaft 102 of the motor 1 is disposed on the cover member 101B side. The output shaft 102 of the motor 1 is inserted and fixed in a resin-made first gear 103 having a concavo-convex portion formed around it. When the output shaft 102 rotates, the first gear 103 also rotates.

  The positioning plate 101C includes a positioning hole 101j, and positions the transmission shaft 104 extending in a direction parallel to the output shaft 102 of the motor 1 in the positioning hole 101j so as to be rotatable. The transmission shaft 104 fixes a second gear 105 made of resin around the bush through a bush or the like. The second gear 105 having irregularities around it is rotatably disposed in the resin cover member 101B. The first gear 103 and the third gear 106 are arranged so as to mesh with each other via the second gear 105.

  A screw shaft 107 is disposed in the screw shaft chamber 101b, and the screw shaft 107 is rotatably supported by a ball bearing 114 attached to the positioning plate 101C. The screw shaft 107 has a male screw groove 107a on the outer peripheral surface. Further, the screw shaft 107 passes through a cylindrical nut 115 in the screw shaft chamber 101b.

  A female screw groove 115a is formed on the inner peripheral surface of the nut 115 so as to face the male screw groove 107a. In the spiral space (rolling path) formed by the male screw groove 107a and the female screw groove 115a, a large number of balls 116 are arranged to roll freely. The nut 115 is relatively movable in the axial direction parallel to the extending direction of the screw shaft 107 in the screw shaft chamber 101 b, and has a detent that does not rotate around the screw shaft 107 in synchronization with the rotation of the screw shaft 107. It has been subjected. Note that a nut 115 that is an axial movement element, a screw shaft 107 that is a rotation element, and a ball 116 that is a rolling element constitute a ball screw mechanism.

  The end of the screw shaft 107 penetrates into a bag hole 117a formed in the round shaft-shaped drive shaft 117. The drive shaft 117 is coaxially fitted to the nut 115 and is connected by a pin or a cotter so as to move integrally. The drive shaft 117 is supported by the bush 118 so as to be movable in the axial direction with respect to the housing main body 101A. A seal 119 is disposed on the outside of the bush 118. The seal 119 prevents foreign matter such as moisture and dust from entering between the housing body 101A and the drive shaft 117. In addition, a hole for connecting to the operation rod 155 described above is formed at the end of the drive shaft 117 protruding from the housing main body 101A.

  The third gear 106 made of resin is attached to the end portion of the screw shaft 107 so as not to be relatively rotatable by serration coupling. A support member 108 is attached to the positioning plate 101C so as to cover a part of the third gear 106. The second gear 105 and the third gear 106 are arranged so as to mesh with each other. Thereby, the 1st gear 103, the 2nd gear 105, and the 3rd gear 106 comprise a power transmission mechanism. This power transmission mechanism is a reduction gear mechanism in which the rotation of the motor 1 is decelerated and the screw shaft 107 is rotated by the meshing of the first gear 103, the second gear 105, and the third gear 106.

  The cover member 101B acts as a gear cover that seals the first gear 103, the second gear 105, and the third gear 106 so that foreign matter does not enter the first gear 103, the second gear 105, and the third gear 106. Note that it is preferable that the first gear 103, the second gear 105, and the third gear 106 be made of different resin materials for meshing gears because wear can be suppressed.

<Motor>
The motor 1 is an electric motor that rotates the output shaft 102. The reduction gear mechanism described above reduces the rotational speed of the output shaft 102 of the motor 1 and transmits it to the ball screw mechanism. The ball screw mechanism converts the rotation of the output shaft 102 into a linear motion and moves the screw shaft 72. The reduction gear mechanism and the ball screw mechanism serve as a drive mechanism for the drive shaft 117. Next, the internal structure of the motor 1 will be described with reference to FIGS.

  FIG. 4 is an explanatory diagram for explaining the rotor of the motor. FIG. 5 is an explanatory diagram for explaining the relationship between the rotor and the stator of the motor according to the present embodiment. The motor 1 according to the present embodiment is a so-called brushed motor, and an armature (armature) core 21 is a rotor 20 that rotates, and permanent magnet members 11N and 11S are stators 10.

  The rotor 20 shown in FIG. 4 includes an armature core 21, a commutator 22, an output shaft 102, and an excitation coil and a brake coil described later. As shown in FIG. 5, the armature core 21 is disposed between the permanent magnet members 11 </ b> N and 11 </ b> S of the stator 10 so as to be rotatable around the output shaft 102.

  The armature core 21 is formed with core slots (magnetic poles) A1 to A10 that protrude to the outer periphery. The armature core 21 is made of a soft magnetic material, such as pure iron or silicon steel plate. The commutator 22 is formed with the same number of commutator segments C1 to C10 as the core slots (magnetic poles) A1 to A10. The commutator 22 is a conductive member that contacts the brushes 25 </ b> A and 25 </ b> B, receives power from a power source outside the motor 1, and periodically changes the current direction.

  The stator 10 includes permanent magnet members 11N and 11S arranged on the inner wall of the motor case 12 so as to face each other with the rotor 20 therebetween. The permanent magnet member 11N is magnetized to the north pole on the rotor 20 side, and the permanent magnet member 11S is magnetized to the south pole on the rotor 20 side. The motor case 12 is preferably made of a soft magnetic material, and is made of pure iron, for example. Thereby, the motor 1 can reduce the leakage magnetic field of the permanent magnet members 11N and 11S.

<Electromagnetic brake mechanism>
FIG. 6 is an explanatory diagram illustrating the relationship between the commutator and the brush of the motor according to the present embodiment. 7 and 8 are explanatory diagrams for explaining the operation of the motor according to the present embodiment. Here, the armature core 21 shown in FIG. 5 is formed with core slots (magnetic poles) A1 to A10. In order to explain the operation principle, the case where there are three core slots is schematically shown in FIGS. I will explain it.

  A rotor 20A corresponding to the rotor 20 includes core slots 22a1, 22a2, 22a3, a commutator 22a, exciting coils 23b1, 23b2, 23b3, and brake coils 24L1, 24L2, 24L3. The permanent magnet members 11n and 11s correspond to the permanent magnet members 11N and 11S. The brushes 25a and 25b correspond to the brushes 25A and 25B.

  As shown in FIG. 6, the commutator 22 a contacts the brushes 25 a and 25 b supplied with power from the power source V. Excitation coils 23b1, 23b2, and 23b3 shown in FIG. 7 are made of a conductor such as copper, and are wound around the core slots 22a1, 22a2, and 22a3, respectively. The exciting coils 23b1, 23b2, and 23b3 are electrically connected to the commutator 22a. Each of the core slots 22a1, 22a2, and 22a3 is wound with brake coils 24L1, 24L2, and 24L3 that are formed of a conductor such as copper and are annularly connected to form a closed circuit.

  As shown in FIG. 7, the brushes 25a and 25b described above are connected to an external circuit including a switch Sw that opens and closes energization of the power supply V. A current i from the power source V is energized from the brushes 25a and 25b by the switch Sw. The exciting coils 23b1 and 23b2 energized from the brushes 25a and 25b through the commutator 22a magnetize the core slots 22a1 and 22a2. The magnetized core slots 22a1 and 22a2 repel or attract each of the permanent magnet members 11n and 11s to generate a rotational force Fr.

  As shown in FIG. 7, the energized DC current i pulsates each time the brushes 25a and 25b pass between the commutator pieces of the commutator 22a. The AC component of the DC current i due to this pulsation is called a current ripple. When the DC current i has a voltage on the vertical axis and time on the horizontal axis, either a positive or negative starting current flows when the motor starts depending on the direction of energization of the motor 1. Thereafter, when the motor 1 rotates at a constant rotation speed, a constant current flows through the motor 1 as the direct current i. In this case, the direct current i includes a pulsating flow. This pulsating flow is called a current ripple waveform. For example, the current ripple waveform of one rotation of the rotor 20A generates three waveforms that are the same as the number of commutator pieces of the commutator 22a. Note that the direct current i includes the above-described current ripple waveform even if PWM control described later is performed.

  As shown in FIG. 8, the current i from the power source V is interrupted by the switch Sw. The exciting coils 23b1 and 23b2 do not magnetize the core slots 22a1 and 22a2, and the rotational force Fr disappears, but the rotor 20A continues to rotate due to the inertial force. The brake coils 24L1, 24L2, and 24L3 sequentially pass the magnetic field between the permanent magnet members 11n and 11s. The magnetic fields of the permanent magnet members 11n and 11s generate a voltage E in the brake coils 24L1, 24L2, and 24L3. Here, the voltage E can be obtained by an induced voltage equation represented by the following equation (1).

  Here, p is the number of magnetic poles, a is the number of parallel conductors, Z is the number of turns of the brake coil, N is the number of rotations of the motor, and φ is the magnetic flux of the permanent magnet members 11n and 11s. Thus, the voltage E is generated in the brake coils 24L1, 24L2, and 24L3 as the rotor 20A rotates faster due to the inertial force. As a result, in each of the core slots 22a1, 22a2, and 22a3 magnetized by the brake coils 24L1, 24L2, and 24L3, a force Fb in a direction opposite to the direction of rotation due to inertia occurs. That is, the brake coils 24L1, 24L2, and 24L3 serve as an electromagnetic brake mechanism and suppress the rotation of the rotor 20A.

Note that the characteristic curve of the motor 1 is that when the brake coil 24L1, 24L2, 24L3 is not provided, the voltage obtained by subtracting the voltage E of the brake coil 24L1, 24L2, 24L3 from the power supply voltage is the voltage at no load. Become. Since there is no rotation when the motor is restrained, the brake coil voltage is E = 0 and becomes the restraining torque at the power supply voltage. Note that the no-load current also increases because torque is generated. Here, the torque T of the motor 1 can be obtained by the following equation (2). Note that _Ia is a current flowing through the exciting coils 23b1, 23b2, and 23b3.

  The torque T of the motor 1 is reduced by the number of rotations N due to the presence of the brake coils 24L1, 24L2, and 24L3. Is smaller, the rotor 20A can rotate.

  The case where there are three core slots has been schematically described with reference to FIGS. Next, excitation coils B1 to B10 corresponding to the above-described excitation coils 23b1, 23b2, and 23b3 will be described with reference to FIG. FIG. 9 is an explanatory diagram for explaining the winding of the exciting coil of the motor according to the present embodiment.

  Excitation coils B1 to B10 are wound around the core slots A1 to A10 shown in FIG. The windings of the exciting coils B1 to B10 will be described as a representative of the exciting coils B1 and B2. In the exciting coil B1, the end of the exciting coil B1 is electrically connected to the commutator segment C1. The exciting coil B1 passes from the commutator segment C1 between the core slots A10 and A1, and extends between the core slots A4 and A5. The exciting coil B1 is electrically connected to the commutator segment C2 from between the core slots A4 and A5.

  Next, in the exciting coil B2, the end of the exciting coil B2 is electrically connected to the commutator segment C2. As a result, the excitation coil B2 is connected to the excitation coil B1. The exciting coil B2 passes from the commutator segment C2 between the core slots A1 and A2 and extends between the core slots A5 and A6. The exciting coil B2 is electrically connected to the commutator segment C3 from between the core slots A5 and A6.

  Similarly to the excitation coils B1 and B2, the excitation coils B3 to B10 are wound between any of the adjacent core slots A1 to A10 and connected to any of the commutator segments C1 to C10. A plurality of exciting coils B1 to B10 are wound around the core slots A1 to A10.

  The exciting coils B1 to B10 of the present embodiment are drum windings called so-called lap windings. The exciting coils B <b> 1 to B <b> 10 of the present embodiment may be drum windings called so-called wave windings.

  Further, brake coils L1 to L10 corresponding to the brake coils 24L1, 24L2, and 24L3 will be described with reference to FIG. FIG. 10 is an explanatory diagram illustrating windings of a brake coil of the motor according to the present embodiment.

  Brake coils L1 to L10 are wound around the core slots A1 to A10 shown in FIG. The windings of the brake coils L1 to L10 will be described on behalf of the brake coils L1 and L2. The brake coil L1 has an end portion of the brake coil L1 electrically connected to the commutator segment C1. The brake coil L1 passes between the commutator segment C1 and between the core slots A10 and A1, and extends between the core slots A4 and A5. The brake coil L1 is electrically connected to the commutator segment C1 from between the core slots A4 and A5. As a result, the brake coil L1 is wound around the armature core 21 and connected in an annular shape so as to form a closed circuit.

  Next, in the brake coil L2, the end of the brake coil L2 is electrically connected to the commutator segment C2. The brake coil L2 passes from the commutator segment C2 between the core slots A1 and A2 and extends between the core slots A5 and A6. The brake coil L2 is electrically connected to the commutator segment C2 from between the core slots A5 and A6. As a result, the brake coil L2 is wound around the armature core 21 and connected in an annular shape so as to form a closed circuit.

  Similarly to the brake coils L1 and L2, the brake coils L3 to L10 are wound between any one of the adjacent core slots A1 to A10 and connected to any one of the commutator segments C3 to C10. As described above, since a plurality of exciting coils B1 to B10 are wound around the core slots A1 to A10, the brake coils L1 to L10 overlap the exciting coils B1 to B10 and are wound around the armature core 21. The number of turns of each of the brake coils L1 to L10 is smaller than the number of turns of each of the exciting coils B1 to B10.

<Motor control device>
FIG. 11 is a block diagram illustrating a motor control device according to the present embodiment. As shown in FIG. 11, in the motor control device 9, the motor 1 and the control device 40 are connected. In the motor control device 9, the control device 40 and the current detector 453 are connected.

  The control device 40 is a computer system such as a microcomputer. For example, as shown in FIG. 11, an input interface 40a, an output interface 40b, a CPU (Central Processing Unit) 40c, a ROM (Read Only Memory) 40d, a RAM (Random Access Memory) 40e, and an internal storage device 40f And. The input interface 40a, output interface 40b, CPU 40c, ROM 40d, RAM 40e, and internal storage device 40f are connected by an internal bus.

  The input interface 40a can receive the output signal SA from the current detector 453 and output it to the CPU 40c. The output interface 40 b receives an instruction signal from the CPU 40 c and outputs a motor control signal SM to the motor 1. The motor control signal SM is, for example, a PWM (Pulse Width Modulation) output. Alternatively, the motor control signal SM may be output from a DC power source, for example.

  A program such as BIOS is stored in the ROM 40d. The internal storage device 40f is, for example, an HDD (Hard disk drive) or a flash memory, and the internal storage device 40f stores an operating system program or an application program. The CPU 40c implements various functions by executing programs stored in the ROM 40d and the internal storage device 40f while using the RAM 40e as a work area. Note that the internal storage device 40f or the RAM 40e serves as the storage unit 40E.

  As described above, in the motor control device 9, the control device 40 calculates the motor control signal SM of the motor 1 based on the output signal SA. Next, the control device 40 can control the motor 1 based on the calculated motor control signal SM. Next, the operation of the actuator according to this embodiment will be described.

<Actuator operation>
FIG. 12 is an explanatory diagram for explaining the operation of the actuator according to the present embodiment in relation to the motor current and time. FIG. 12 shows the relationship between the motor current and time as a motor current curve Im. In FIG. 12, the idle running section S, the deflection section Tb, and the holding section U, which are described above as the section where the operating rod 155 driven by the actuator 100 is located, are displayed. In FIG. 12, a thrust curve Mn indicating a thrust that is an actual load in the direction of an arrow X shown in FIGS. 1-1, 1-2, and 1-3, and a current that indicates a current ripple component detected by the current detector 453. Ripple Ir is displayed along the time axis of the motor current curve Im. FIG. 12 also shows a current ripple pulse Irp obtained by measuring the number of current ripple waveform pulses of the current ripple Ir. Further, in FIG. 12, a release section W is displayed as a section where the operating rod 155 driven by the actuator 100 is located.

  In the release section W shown in FIG. 12, the operating rod 155 shown in FIG. 1-3 moves in the direction opposite to the direction of the arrow X, and the brake band 130 tightens the brake drum 160 to stop the rotation of the brake drum. The operating rod 155 is displaced in the direction of releasing the braking force. In the release section W, the brake drum 160 that has stopped rotating is rotating. The release boundary Q indicates the start position of the operation in which the frictional force acting between the brake band 130 and the brake drum 160 decreases and the brake drum 160 rotates. For example, the release section W can be a section from the release boundary Q to the start position J of the idle section S that is the reference position.

  The motor control device 9 described above preferably increases the current supply to the motor in the idle running section S shown in FIG. 12 and shortens the shift time of the automatic transmission. In the idling section S, the motor 1 displaces the operating rod 155 from the start position J of the idling section S to the initial braking region P in a state where the reaction force applied from the brake band 130 is small.

  Next, in the initial braking region P, the operating rod 155 is displaced together with the applying bracket 136, and the brake band 130 generates a braking force to the brake drum 160. In order to reduce the shock caused by the braking force, it is preferable that the motor control device 9 grasps the position of the initial motion braking region P and decelerates the rotational speed of the motor 1 immediately before the initial motion braking region P. In a conventional hydraulic control actuator, hydraulic oil serves as a damper. On the other hand, in the brake band device 110 by motor control, the pressure due to the inertial rotation of the motor 1 is easily transmitted to the brake band 130 via the operating rod 155.

  For example, in the case of the motor 1 that does not include the brake coils L1 to L10 that are electromagnetic brake mechanisms, when attempting to decelerate in the initial braking region P, the armature core 21 rotates by the action of inertial force even if the power supply to the motor 1 is reduced. And the thrust which is an actual load increases in the direction of the arrow X shown to FIGS. That is, there is a possibility that an inertia load increases due to the rotation of the rotor 20 due to the inertia.

  The motor 1 of the present embodiment including the electromagnetic brake mechanism (brake coils L1 to L10) tends to decelerate in the initial braking region P. In this case, the armature core 21 is rotated by the action of inertial force, but the brake coils L1 to L10 apply a force in the direction opposite to the rotation direction to the armature core 21 by this rotation, and the thrust that is the actual load in the direction of the arrow X Is suppressed from increasing. As a result, the difference between the command load and the actual load is suppressed, and the relationship between the command load and the actual load tends to follow an ideal load curve.

  In the deflection section Tb, the reaction force from the brake band 130 applied to the operating rod 155 increases as the stroke of the operating rod 155 increases.

  For example, the band brake device 110 may give a driver a sense of incongruity as a shock when the rate of increase in reaction force increases. For this reason, it is preferable to gradually increase the current to the motor 1 and increase the load by which the operating rod 155 gradually pushes the brake band 130 to increase the thrust. For example, the motor control device 9 performs control so that the current curve Im to the motor 1 has a constant current increase rate in the deflection section Tb shown in FIG. As the current Im flowing to the motor 1 increases, the thrust of the thrust curve Mn shown in FIG. 12 also increases.

  Further, in the holding section U shown in FIG. 12, the motor control device 9 supplies the motor 1 with a current for the operating rod 155 to keep pressing the apply bracket 136. Thereby, the actuator 100 can maintain the braking force generated by the brake band 130 and can maintain the rotation of the brake drum 160 stopped.

  As described above, in the actuator 100 of the present embodiment, the operating rod 155 is displaced together with the apply bracket 136 in the initial motion braking region P, and the brake band 130 generates a frictional force that brakes the brake drum 160. In order to reduce the shock caused by the braking force that brakes the brake drum 160, it is important that the motor control device 9 accurately detects the initial motion braking region P to control the motor 1.

<Actuator control block>
FIG. 13 is a block diagram illustrating a control block of the actuator. As shown in FIG. 13, the control block includes a command for fastening the brake band 130 and the brake drum 160 (rotation of the brake drum 160 is stopped), a brake band 130 and a brake drum based on a shift command in the automatic transmission. The control is performed in accordance with the engagement / non-engagement command unit 41 that selects and commands a command to make the gear 160 non-engaged (a state in which the brake drum 160 rotates).

  The control block includes a section command generating section 42 that generates a command to the actuator 100 based on the fastening non-fastening command section 41, a command switching section 43 that switches to the generated section, and a thrust corresponding to the switched section. A thrust-current conversion unit 44 that converts the current to the motor 1 so as to have a current, a current control unit 45 that controls the current to the motor 1, and a current amplification unit 461 that amplifies the current value detected by the current control unit 45 A high pass filter (HPF) 462, a low pass filter (LPF) 463, a ripple component amplification unit 464, a ripple voltage threshold unit 471, a comparator 472, and a pulse integration unit 473. Including.

  The section command generation unit 42 includes an idle section command 421, a deflection section command 422, a holding section command 423, and a release section command 424.

  The idling section command 421 is a command for controlling the motor 1 in the idling section S described above. The deflection section command 422 is a command for controlling the motor 1 in the deflection section Tb described above. The holding section command 423 is a command for controlling the motor 1 in the holding section U described above. The release section command 424 is a command for controlling the motor 1 in the release section W described above.

  The section command generation unit 42 switches between the free running section command 421 and the deflection section command 422, the holding section command 423, based on the control command by the fastening non-fastening command section 41 and information of the pulse integration section 473 described later. Then, the switching with the release section command 424 is selected and output.

  The command switching unit 43 transmits the command to the thrust-current conversion unit 44 while switching the command output from the section command generation unit 42 as necessary. Note that the output of switching between the deflection section command 422 and the holding section command 423 can be processed based on the accumulated time information of the deflection section command 422 stored in advance by the section command generation unit 42. Next, the thrust-current conversion unit 44 outputs a motor current target value that is a commanded thrust to the current control unit 45.

  The current control unit 45 includes a PI controller 451, a PWM output 452, a current detector 453, and a feedback addition point D1. The feedback addition point D1 outputs a deviation between the motor current target value transmitted from the thrust-current converter 44 and the current value detected by the current detector 453 to the PI controller 451. The PI controller 451 processes one or more of proportional control and integral control according to the deviation. The control output responded by the PI controller 451 becomes a PWM output by the PWM output 452, and current is supplied (motor energization) to the motor 1 of the actuator 100. The current detector 453 detects the PWM output current and feeds it back to the feedback addition point D1 described above.

  As the current detector 453, a shunt resistor or a magnetic current sensor can be used. For example, the magnetic current sensor is a Hall element. The current detector 453 detects the current value of the motor 1. In the motor 1, the commutator 22 contacts the brushes 25A and 25B. For this reason, a current ripple corresponding to the number of commutator segments C1 to C10 that are commutator segments per rotation of the rotor 20 of the motor 1 is generated in the current detected by the current detector 453. Since the commutator segments C1 to C10 are fixed to the motor shaft 102, the rotation angle of the motor shaft 102 can be calculated by measuring the number of current ripples.

  The current amplifying unit 461 amplifies the current value detected by the current detector 453. From the amplified current value, a DC component is removed by a high-pass filter (HPF) 462 and a current ripple component is extracted by a low-pass filter (LPF) 463. The ripple component amplification unit 464 amplifies the extracted current ripple component. The ripple voltage threshold value unit 471 includes the storage unit 40E described above, and stores threshold information of ripple voltage. The comparator 472 converts, for example, the current ripple component Ir shown in FIG. 12 into a ripple pulse Irp based on the current ripple component amplified by the ripple component amplifying unit 464 and the threshold voltage threshold information stored in the ripple voltage threshold unit 471. The pulse integrating unit 473 integrates the number of ripple pulses Irp and calculates a ripple integrated value.

  For example, the pulse integration unit 473 calculates the stroke St of the actuator using the ripple integration value Ri as shown in the following formula (3), and transmits it to the section command generation unit 42. Sr is the number of commutator pieces (commutator segments). g is a reduction ratio of the reduction gear mechanism. The ball screw lead l is a displacement amount that the drive shaft 117 and the operating rod 117 stroke when the screw shaft 107 makes one rotation.

The storage means 40E described above stores in advance information on the number of commutator pieces Sr, the reduction ratio g of the reduction gear mechanism, and l of the ball screw lead. In addition, the storage unit 40E stores, for example, a stroke St corresponding to the free running section S or the release section W with the start position J of the free running section S as a reference.

  The section command generation unit 42 compares whether or not the stroke St calculated by the CPU 40c is within a stroke corresponding to the idle running section S. The motor control device 9 can easily determine the switching timing between the idle running section command 421 and the deflection section command 422 from the calculated stroke St. Alternatively, the section command generation unit 42 compares whether or not the stroke St calculated by the CPU 40c is within the stroke corresponding to the release section W. The motor control device 9 can easily determine the end timing of the release section command 424 from the calculated stroke St.

  The fastening non-fastening command unit 41 preferably sends a pulse clear command to the pulse integrating unit 473 in the deflection section Tb and the holding section U. Thereby, in the deflection section Tb and the holding section U, the procedure for generating the ripple pulse Irp can be omitted.

  For example, in the deflection section Tb, it is preferable to gradually increase the thrust with respect to the elastic force received from the brake band 130. As a result, the motor current curve Im increases. The amplitude of the current ripple Ir changes depending on the motor current Im. For this reason, if the setting of the high-pass filter (HPF) 462 or the low-pass filter (LPF) 463 at the time of extraction is not changed depending on the amount of the motor current Im, extraction of some current ripples may be lost. . Alternatively, if the threshold stored in the ripple voltage threshold unit 471 is not changed, extraction of some current ripples may be lost.

  In the idle section S and the release section W, the frictional force that causes the brake band 130 to brake the brake drum 160 is not generated, or is generated only to the extent that there is little influence as a reaction force to the operating rod 155. For this reason, the fluctuation of the load applied to the motor 1 is small. As a result, the motor current curve Im shown in FIG. 12 falls within the current value within a substantially constant range. Thereby, it becomes easy to set the threshold value stored in the ripple voltage threshold value unit 471, and the extraction accuracy of the extracted current ripple component can be maintained. Further, by increasing the extraction accuracy of the current ripple component, the pulse integration unit 473 can integrate the number of ripple pulses Irp and calculate a highly accurate stroke St from the ripple integration value. Note that, at the start position J of the idle running section S and the release boundary Q, the starting current Ims flows to the motor 1, but the time is short. If the ratio of the stroke corresponding to the starting current Ims to the entire stroke is sufficiently small and the resolution is sufficient, the motor control device 9 may ignore the stroke of the operating rod 155 corresponding to the starting current Ims. Alternatively, the motor control device 9 may store the time during which the starting current Ims flows in the storage unit, and may perform an operation of adding a stroke of the operating rod 155 corresponding to the starting current Ims when extracting the current ripple component.

  Further, in the holding section U, a current is applied to the motor 1, but the rotor 20 does not rotate or hardly rotates, so the ripple integrated value need not be calculated. Next, the control procedure of the actuator 100 will be described.

  FIG. 14 is a flowchart for explaining the control procedure of the actuator. First, in step S101, the motor control device 9 detects whether it is the idle section S or the release section W shown in FIG. 12 based on the information on the stroke St stored in the storage means 40E at the present time.

  If it is the idle section S or the release section W (step S101, Yes), the motor control device 9 advances the process to step S102. In step S102, the motor control device 9 converts the current ripple component Ir into a ripple pulse Irp, and the pulse integration unit 473 integrates the number of ripple pulses Irp (pulse integration) to calculate a ripple integrated value.

  If it is not the idle section S or the release section W (step S101, No), the motor control device 9 advances the process to step S103. In step S103, the motor control device 9 detects the current value for controlling the motor 1 by the current detector 453, and detects the control time commanded by the deflection section command 422 or the holding section command 423. The control time is, for example, a standard integrated time during which the operating rod 155 is displaced from the initial braking region P or the fastening boundary G in accordance with the current value for controlling the motor 1.

  Next, the motor control device 9 advances the process to step S104 after the process of step S102 or step S103. In the case of the idling section S or the release section W, in step S104, the motor control device 9 calculates the stroke St of the actuator using the ripple integrated value Ri as shown in the above-described equation (3), and the storage means Store in 40E. In the case of the deflection section Tb or the holding section U, in step S104, the stroke of the actuator 100 is calculated from the current value for controlling the motor 1 and the control time commanded by the deflection section command 422 or the holding section command 423, and stored. Store in means 40E.

  Next, the motor control device 9 advances the processing to step S105. The motor control device 9 determines whether either a command for fastening the brake band 130 by the actuator 100 or a command for putting the brake band 130 in the non-engaged state by the actuator 100 is completed based on a command for shifting in the automatic transmission. To detect.

  Specifically, when the motor control device 9 performs current control of the motor 1 in the holding section U, it is assumed that the fastening command is completed.

  The actuator 100 increases the reduction ratio of the reduction gear mechanism so that the friction when the motor 1 is not energized is applied to the braking force (band brake engagement holding force) that maintains the state where the brake band 130 stops the rotation of the brake drum 160. ) Is preferable.

  For example, the actuator 100 preferably satisfies the following formula (4) with respect to the band brake fastening holding force.

  Here, the values of the sliding static friction and the disturbance static friction of the linear motion portion are smaller than the value on the entire left side of the equation (4). The ball screw lead needs to secure the stroke of the ball screw mechanism and ensure the efficiency. For this reason, in order to satisfy | fill Formula (4), it is preferable to increase the holding torque of the ball screw shaft at the time of no electricity supply. The holding torque of the ball screw shaft when not energized can be expressed by the following formula (5).

  From equation (5), it can be seen that the holding torque of the ball screw shaft when no power is supplied can be increased by increasing the reduction ratio of the reduction gear mechanism.

  As described above, by satisfying the relationship of the expression (4), the motor 1 does not reversely rotate due to the reaction force applied from the brake band 130 to the operating rod 155. The actuator 100 can maintain the state where the brake band 130 stops the rotation of the brake drum 160 without continuing to energize the motor 1. For example, in the holding section U shown in FIG. 12, when the motor current curve Im is viewed, the motor current does not flow, but the thrust of the thrust curve Mn can maintain substantially the same thrust as when the motor current is supplied. Further, the ball screw mechanism has high transmission efficiency, and can efficiently convert rotation as linear motion. Even when the ball screw mechanism is used, it is possible to maintain the state in which the brake band 130 stops the brake drum 160 by increasing the reduction ratio of the reduction gear mechanism. Since the motor 1 is not energized, the heat generation of the motor 1 is suppressed and the power consumption of the actuator 100 can be suppressed.

  Or when the control time which the holding | maintenance area command 423 commanded by the to-be-fastened command is complete | finished, the motor control apparatus 9 clears the ripple integrated value mentioned above. The motor controller 9 rotates the motor in the direction opposite to the arrow X direction shown in FIG. The motor control device 9 preferably stores in the storage means 40E the target position of the operating rod 155 in the release section W, for example, the stroke of the operating rod 155 that becomes the start position J of the idle section S. When the motor control device 9 detects the release boundary Q at which the brake band 130 releases the engagement of the brake drum 160, the motor control device 9 can calculate the stroke St of the operating rod 155 from the release boundary Q from the current ripple component. The motor control device 9 assumes that the non-engagement command is completed when the calculated stroke St of the operating rod 155 reaches the target position described above. When the fastening command or the non-fastening command is completed (step S105, Yes), the motor control device 9 ends the process.

  When the fastening command or the non-fastening command is not completed (No at Step S105), the motor control device 9 returns the process to Step S101. By this procedure, in step S101, the motor control device 9 can detect the switching from the idle running section S to the deflection section Tb.

  When the initial braking region P, which is a switching boundary from the idle running section S to the deflection section Tb, is detected, the brake band 130 generates a braking force. In order not to give a shock due to the generation of the braking force, the motor control device 9 can rapidly reduce the current to the motor 1 as shown in FIG.

  Further, in the motor 1 of the present embodiment including the electromagnetic brake mechanism (brake coils L1 to L10), when the motor 1 is decelerated in the initial braking region P, the rotor 20 tends to continue to rotate due to the action of inertial force. As a result of this rotation, the brake coils L1 to L10 give the rotor 20 a force in the direction opposite to the rotational direction, and an increase in thrust, which is an actual load, in the direction of the arrow X is suppressed. As a result, in the initial braking region P in FIG. 12, the increase in thrust is suppressed without the stroke amount protruding.

  As described above, the actuator 100 according to the present embodiment is an actuator that controls the displacement of the operating rod 155 that applies a load in order to elastically deform the brake drum 160 that is a rotating body into the brake band 130 that brakes. The actuator 100 converts the motor 1, a rotational motion from the output shaft 102 of the motor 1 into a linear motion, a linear motion mechanism that gives the displacement generated by the linear motion to the operating rod 155, and a current supplied to the motor 1. A current detector 453 for detection and a control device 40 are included. The control device 40 extracts a current ripple component from the current detector 453. The control device 40 calculates a stroke St that is a displacement amount of the operating rod 155 in the idle running section S from when the brake band 130 starts braking the brake drum 160 to when braking force is generated from the current ripple component. be able to. For this reason, the control device 40 can easily grasp the timing at which the braking force is generated in the initial braking region P.

  Further, the control device 40 displaces the operating rod 155 so as to release the braking of the operating rod 155 from the state where the rotation of the brake drum 160 is stopped by the braking of the brake band 130, and the brake drum 160 rotates. The stroke St, which is the amount of displacement of the actuating rod 155, in the release section W from can be calculated from the current ripple component. Therefore, the control device 40 can easily grasp the position of the operating rod 155 in the release section W. For this reason, in the release section W, the operating rod 155 can be reliably returned.

  Even if the motor 1 or the housing 101 of the actuator 100 does not include a rotation sensor, a load sensor, a position sensor, or the like, the control device 40 extracts the current ripple component from the current detector 453, and the free running section The stroke St, which is the displacement amount of the operating rod 155 in S or the release section W, can be calculated. When the rotation sensor, the load sensor, the position sensor, and the like are omitted, the cost can be reduced and the housing 101 of the motor 1 or the actuator 100 can be downsized.

  The motor 1 of the actuator 100 includes an exciting coil B1 to B10 and brake coils L1 to L10 wound around the armature core 21, magnetized permanent magnet members 11N and 11S, and an output shaft that rotates together with the armature core 21. 102.

  The armature core 21 that rotates by energization of the excitation coils B1 to B10 becomes the rotor 20, and the position thereof changes relative to the permanent magnet members 11N and 11S. The brake coils L1 to L10 that pass through the magnetic fields of the permanent magnet members 11N and 11S are wound around the armature core 21 and connected in an annular shape, and the rotor 20 (output shaft 102) rotates due to inertia in the rotating armature core 21. A force in the direction of rotation and the direction of reverse rotation can be applied.

  Thereby, when the energization of the exciting coils B1 to B10 is turned off, the rotation of the output shaft 102 due to inertia is suppressed early. That is, the motor 1 follows off of energization of the exciting coils B1 to B10, and the rotation of the output shaft 102 stops early. Further, the rotation of the output shaft due to the inertia of the so-called brushed motor is suppressed early. Further, even if the motor 1 rotates at a high speed, the output shaft 102 is prevented from continuing to rotate due to inertia. As a result, it becomes easy to control even if the motor is driven at high speed.

  The band brake device 110 can perform motor control to alleviate a shock caused by the generation of the braking force at the timing when the braking force is generated in the initial braking region P. Thereby, it is possible to reduce a shift shock or a sense of incongruity given to the driver.

  Further, the linear motion mechanism preferably includes a ball screw mechanism including a nut 115 that is a moving element in the axial direction, a screw shaft 107, and a ball 116 that is a rolling element. Thereby, the rotational motion of the output shaft 102 can be converted into the linear motion of the screw shaft 107. Since the actuator 100 includes the ball screw mechanism, the small force (torque) of the motor 1 can be converted into the thrust of the shaft 72 that is a large force. Since the starting torque can be extremely reduced by rolling the ball 116 of the ball screw mechanism, the actuator 100 is a thrust generating device that can apply a predetermined thrust of the drive shaft 117 by precise fine feed.

  The ball screw mechanism is a linear motion mechanism that converts a rotational motion into a linear motion, and also applies a displacement generated by the linear motion to the operating rod 155 to convert a large displacement (rotation) into a small displacement (linear motion). Has a deceleration action.

  The reduction gear mechanism rotates the screw shaft 107 by reducing the rotation speed of the output shaft 102 of the motor 1 by the meshing of the first gear 103, the second gear 105, and the third gear 106. That is, the reduction gear mechanism is provided between the output shaft 102 and the screw shaft 107 of the ball screw mechanism, and reduces the rotational speed transmitted from the output shaft 102 to the screw shaft 107. Thereby, even if the motor 1 is a small motor, a high output can be taken out. Moreover, the freedom degree of the layout in the housing 101 in which the motor 1 and the screw shaft 107 are arrange | positioned can be raised.

  The actuator 100 of this embodiment described above is applied to the band brake device 110. The actuator 100 is suitable for an electric actuator used in general industrial electric motors, automobiles, ships and the like. For example, the actuator 100 can replace a hydraulic control mechanism that applies pressure or thrust. In addition, the actuator 100 includes a stroke section in which the load variation due to the reaction force is small as in the above-described idle section, and a stroke section in which the driven mechanism applies a load to the elastically deforming member, such as in the deflection section. It is preferable to apply to a control mechanism that applies thrust.

DESCRIPTION OF SYMBOLS 1 Motor 9 Motor control apparatus 10 Stator 11N, 11S, 11s, 11n Permanent magnet member 21 Armature core 23b1, 23b2, 23b3, B1-B10 Excitation coil 24L1, 24L2, 24L3, L1-L10 Brake coil 20, 20A Rotor 22a1, 22a2 , 22a3, A1-A10 Core slot 22, 22a Commutator 25A, 25B, 25a, 25b Brush 40 Control device 453 Current detector 100 Actuator 102 Output shaft 107 Screw shaft 110 Band brake device 115 Nut 117 Drive shaft 130 Brake band 131 Strap 132 Lining 136 Apply bracket 151 Apply means 155 Actuating rod 156 Anchor pin C1 to C10 Commutator segment (commutator piece)

Claims (5)

An actuator for controlling the displacement of a driven mechanism that applies a load to the elastic deformation member in order to elastically deform the elastic deformation member that brakes the rotating body,
A motor,
A linear motion mechanism that converts a rotational motion from the output shaft of the motor into a linear motion, and gives a displacement generated by the linear motion to the driven mechanism;
A current detector for detecting a current supplied to the motor;
From the state in which the rotation of the rotating body is stopped by the amount of displacement of the driven mechanism from when the elastic deformation member starts braking the rotating body to when the braking force is generated, and braking of the elastic deformation member A displacement amount of at least one driven mechanism among the displacement amount of the driven mechanism after the driven mechanism is displaced so as to release the braking of the elastic deformation member and the rotating body rotates. A control device that calculates from the current ripple component extracted from the current detector;
The actuator characterized by including. The motor is
An armature core coupled to the output shaft; an exciting coil wound around the armature core; a permanent magnet member that is magnetized and changes in position relative to the armature core; and the armature core A brake coil that is wound and connected in a ring so as to form a closed circuit,
The actuator according to claim 1, wherein a force in a direction opposite to a rotation direction of the armature core that rotates by energization of the excitation coil is applied to the armature core. A motor,
A linear motion mechanism that converts rotational motion from the output shaft of the motor into linear motion;
An actuating rod that is displaced by the linear motion in order to apply a load to the elastically deformable brake band and brake the brake drum in accordance with the elastic deformation of the brake band;
A current detector for detecting a current supplied to the motor;
A current ripple component is extracted from the current detector, and a displacement amount of the actuating rod from when the brake band starts braking the brake drum to when a braking force is generated, and by braking the brake band, the brake drum At least one of the displacement amount of the operating rod after the brake rod is rotated and the brake drum is rotated so that the braking of the brake band is released. A control device for calculating the displacement amount of the operating rod from the current ripple component;
A band brake device comprising: The linear motion mechanism is a ball screw mechanism,
The band brake device according to claim 3, further comprising a reduction gear mechanism that is provided between the output shaft and a screw shaft of the ball screw mechanism and that reduces a rotational speed transmitted from the output shaft to the screw shaft. . A method of controlling a motor for displacing a driven mechanism that applies a load to the elastic deformation member in order to elastically deform an elastic deformation member that brakes a rotating body,
When the elastic deformation member starts braking of the rotating body and when a braking force is generated, the idle mechanism is a section where the driven mechanism is displaced, or the rotation of the rotating body is caused by braking of the elastic deformation member. Detecting a release section in which the driven mechanism is displaced so as to release the braking of the elastically deformable member from a stopped state, and the driven mechanism is displaced after the rotating body is rotated. And steps to
In the detected idle running section or the release section, detecting a current supplied to the motor, extracting a current ripple component from the detected current, and integrating the current ripple component as a pulse;
Performing an operation to set the integrated value of the pulses to a displacement amount of the driven mechanism;
A motor control method comprising:

Images