JP2015001126A - Brake and door closer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a door closer which suppresses speed of a door in a closing direction by a simple configuration.SOLUTION: In a coil 60 provided in a stator 56 of a rotator 50, a resonance circuit 64 to which a capacitor 62 of capacitance C is connected and closed is formed. To a door closer provided with the rotator, torque is transmitted so as to rotate a rotor 54 of the rotator at rotational speed according to speed of a door when the door rotates in a closing direction. In the rotator, counter-electromotive force according to periodically changing induction electromotive force is generated in a coil by rotation of the rotor and the rotational force is given in a direction for suppressing the rotational speed to the rotor of the rotator. Thus, in the door closer, the rotational speed of the rotor is suppressed, and the rotor with the suppressed rotational speed suppresses the speed so as to brake the door.

Description

  The present invention relates to a braking device and a door closer.

  Generally, a door closer attached to a door stores an urging force in a closing direction of the door by rotating an input shaft when the door is opened. Thereby, the door closer rotates the door in the closing direction by the stored urging force, and the door is automatically closed. Moreover, the door closer functions as a braking device that relaxes the rotational speed in the closing direction of the door, closes the door smoothly, and prevents the door from closing suddenly due to being blown by the wind. .

  Patent document 1 is disclosing the door closer which closes a door at constant speed using the power generation control means provided with the rotor which has a magnet, and the stator which has a coil. The door closer of Patent Document 1 charges a charging capacitor with an induced electromotive force generated in a stator coil by rotating a rotor in accordance with the rotation of the door when the door rotates in the closing direction. Is converted into DC power by a step-up chopper circuit using, and the rotation control circuit is operated.

  The rotation control circuit of Patent Document 1 increases the on-duty of the field effect transistor connected to the coil to increase the braking force against the rotation of the rotor when the induction voltage of the coil increases due to the increase in the rotation speed of the rotor. The door is closed at a constant speed.

JP 2000-130005 A

  However, in order to use the electric power obtained by charging the induction electromotive force generated by the rotation of the door in the charging capacitor as the electric power of the rotation control circuit that controls the rotation of the rotor, the circuit configuration becomes complicated and the rotation Control is also complicated.

  The present invention has been made in view of the above-described facts, and an object thereof is to provide a braking device and a door closer that can obtain a desired braking force with a simple configuration.

  The braking device of the present invention generates a induced electromotive force according to the rotational speed in a period synchronized with the rotation of the rotor connected to the braking target and rotated at a rotational speed corresponding to the moving speed of the braking target. A rotating circuit including a stator having a coil to be rotated, and a circuit closed by the coil and a capacitor connected to the coil, and applying a rotational force that suppresses the rotational speed of the rotor by a counter electromotive force generated in the coil. And a braking circuit for braking the movement of the braking target.

  The door closer of the present invention includes a door that opens and closes an opening, an input shaft that is rotated according to rotation in the opening direction and the closing direction of the door, and the input shaft that is rotated in the opening direction of the door. An urging unit that accumulates an urging force and rotates the input shaft in the closing direction of the door by the accumulated urging force; and a rotation speed that is connected to the input shaft and that corresponds to the rotation speed of the input shaft. And a rotor closed by a rotor having a stator having a coil that generates an induced electromotive force according to the rotational speed at a period synchronized with the rotation of the rotor, and a circuit closed by the coil and a capacitor connected to the coil And a braking circuit for braking the rotation of the input shaft by applying a rotational force that suppresses the rotational speed of the rotor by a counter electromotive force generated in the coil.

  The braking device and the door closer of the present invention form a closed circuit in which a capacitor is connected to a coil of a rotator as a braking circuit, and generates a counter electromotive force according to the rotational speed of the rotor. Suppress the speed.

  A closed circuit including a coil and a capacitor indicates a circuit that does not include a power source and that does not receive power. A closed circuit including a coil and a capacitor includes an LC resonant circuit.

  The capacitance of the capacitor can be set to maximize the rotational force that suppresses the rotational speed at a preset rotational speed of the rotor.

  The capacitance of the capacitor can be set so that the resonance frequency of the closed circuit is a frequency corresponding to a preset rotation speed of the rotor.

  The capacitance of the capacitor can be set so that the impedance of the closed circuit is lowest at a preset rotation speed of the rotor.

  Furthermore, the braking device and the door closer of the present invention include a current adjusting unit that connects the coil and the capacitor and adjusts the current value of the closed circuit.

  According to the braking device of the present invention, the movement of the braking target can be braked with a simple configuration in which a capacitor is connected to the coil provided in the rotor of the rotator.

  Moreover, the door closer of the present invention can accurately brake the rotation when the door is closed with a simple configuration in which a capacitor is connected to a coil provided in the rotor of the rotator.

(A) is a front view which shows the principal part of the door which concerns on this embodiment, (B) is a schematic plan view which shows opening and closing of a door. It is a schematic block diagram which shows a closer main body. (A) is a schematic plan view which shows the principal part of a closer body, (B) is a schematic sectional drawing which shows the principal part of a closer body. 1 is a schematic configuration diagram illustrating a braking circuit according to a first embodiment. It is a diagram which shows the measurement result of the braking torque with respect to the rotational speed of the rotor according to the electrostatic capacitance of the capacitor | condenser in the braking circuit which concerns on 1st Embodiment. It is a schematic block diagram which shows the braking circuit which concerns on 2nd Embodiment. It is a diagram which shows the measurement result of the braking torque with respect to the rotational speed of the rotor according to the electrostatic capacitance of the capacitor | condenser in the braking circuit which concerns on 2nd Embodiment. It is a schematic block diagram which shows the braking circuit which concerns on 3rd Embodiment. It is a schematic block diagram which shows the braking circuit which concerns on 4th Embodiment. It is a circuit diagram which shows an example of a variable resistance circuit.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]

  FIG. 1A shows a main part of a door (a hinged door) 10 according to the first embodiment. The door 10 is attached to a door frame (hereinafter referred to as a door frame) 14 provided on a wall 12 such as a building. One end of the door 10 in the width direction (left and right direction in FIG. 1A) is connected to and attached to the door frame 14 via a plurality of hinges 16, and the door 10 rotates around the hinges 16. The opening (not shown) of the wall 12 to be formed is opened and closed.

  A door closer 20 is attached to the door 10. The door closer 20 includes a closer body 22, a bracket 24, a first arm 26 and a second arm 28. As for the door closer 20, the closer main body 22 is attached to the indoor side upper end part of the door 10, and the bracket 24 is attached to the upper edge of the door frame 14, for example.

  An input shaft 30 projects from the upper surface of the closer body 22, and the closer body 22 is connected to the input shaft 30 so that one end of the first arm 26 rotates integrally. The first arm 26 is provided with a pin 32 at the other end, and one end of the second arm 28 is rotatably connected to the pin 32. The bracket 24 is provided with a pin 34, and the other end of the second arm 28 (the end opposite to the first arm) is rotatably connected to the pin 34.

  Thereby, the door closer 20 forms a link mechanism between the door 10 and the door frame 14 connected by the hinge 16 using the first arm 26 and the second arm 28. Further, the door closer 20 rotates the input shaft 30 forward and backward according to the rotation of the door 10 in the opening direction and the closing direction during the opening and closing operation of the door 10, and the input shaft at a rotation speed according to the opening and closing speed of the door 10. 30 rotates.

  As shown in FIG. 1B, the door 10 is hinged between a closed position indicated by a broken line and an open position indicated by a one-dot chain line (for example, a position where the opening is 90 ° with respect to the closed position). Rotating operation is performed in the opening direction (arrow Do direction) and the closing direction (arrow Dc direction) with 16 as an axis. The door closer 20 is provided with a mechanism for limiting the rotation range of the door 10 between the first link 26 and the second link 28 or between the bracket 24 and the second link 26. A known general configuration can be applied to the configuration of the door closer 20 as described above.

  As shown in FIG. 2, the closer body 22 includes a casing 36, and the tip of the input shaft 30 protrudes from the casing 36. For example, the input shaft 30 is formed in a non-circular shape such as a quadrangle in a cross section in the direction perpendicular to the axis of the tip portion, and the input arm 30 is integrated with the first arm 26 by connecting the first arm 26 to the tip portion. Rotate.

  The closer body 22 is provided with an urging portion 38, a gear portion 40, and a braking portion 42 inside the casing 36. FIG. 3A and FIG. 3B show an example of the urging unit 38. 3A shows a schematic plan view of the urging portion 38 viewed from the axial direction of the input shaft 30, and FIG. 3B shows the urging portion 38 along the axial direction of the input shaft 30. The schematic cross section of the principal part is shown.

  As shown in FIGS. 2 and 3A, the closer body 22 is disposed so that the input shaft 30 penetrates the urging portion 38. Further, as shown in FIGS. 3A and 3B, the urging portion 38 is provided with a spiral spring 44 as an example of urging means. As shown in FIG. 3B, the spiral spring 44 has an outer peripheral end 44 </ b> A locked at a predetermined position on the inner surface of the casing 36, and an inner peripheral end 44 </ b> B locked to the input shaft 30. The spiral spring 44 accumulates an urging force that rotates the input shaft 30 in the closing direction of the door 10 when the input shaft 30 is wound in the opening direction of the door 10 (accumulation). Further, the spiral spring 44 urges the input shaft 30 to rotate in the closing direction of the door 10 by the accumulated urging force.

  The door closer 20 rotates the input shaft 30 by the biasing force of the biasing portion 38 in the closing direction of the door 10, and the rotation of the input shaft 30 is transmitted to the bracket 24 via the first arm 26 and the second arm 28. Then, the door 10 is rotated in the closing direction around the hinge 16. As a result, the door 10 is automatically closed by the door closer 20. The urging means used for the urging unit 38 is not limited to the spiral spring 44, and other urging means such as a coil spring can be used. Further, as the urging unit 38, any configuration that accumulates energy by rotating the input shaft 30 in the opening direction of the door 10 and rotates the input shaft 30 in the closing direction of the door 10 by the accumulated force can be applied.

  As shown in FIG. 2, the distal end portion (lower end portion) of the input shaft 30 that penetrates the biasing portion 38 reaches the gear portion 40. The gear unit 40 is formed with a gear train composed of a plurality of gears, and increases the rotational speed of the input shaft 30 for output.

  The gear unit 40 includes, for example, large-diameter gears 46A, 46B, and 46C and small-diameter gears 46D, 46E, and 46F. The large-diameter gears 46A to 46C have a larger diameter and a larger number of teeth than the small-diameter gears 46D to 46F.

  The gear portion 46 rotates integrally with the input shaft 30 by connecting a large-diameter gear 46 </ b> A to the input shaft 30. A small-diameter gear 46D is engaged with the gear 46A (engagement). The gear 46D is disposed coaxially with the gear 46B, and the gear 46D and the gear 46B rotate together. The gear 46E is provided on the shaft 48 and meshed with the gear 46B. A gear 46C is attached to the shaft 48 so that the gear 46C can rotate according to the rotation of the gear 46E. Further, the gear 46C is meshed with the gear 46F, and the gear 46F rotates according to the rotation of the gear 46C.

  Accordingly, the rotation of the input shaft 30 can be transmitted from the gear 46A to the gear 46F at the final stage by the rotation of the input shaft 30 in the gear unit 40. When the rotational speed (the rotational speed of the input shaft 30) input to the gear 46A is transmitted to the gear 46F, the gear unit 40 rotates the input shaft 30 according to the number of teeth of each of the gears 46A to 46F. Is increased and the final gear 46F is rotated.

  Here, the gear part 40 is provided with a one-way clutch mechanism (not shown) on the large-diameter gear 46C. When the shaft 48 rotates in the closing direction of the door 10, the one-way clutch mechanism transmits this rotation to the gear 46C. However, when the shaft 48 rotates in the opening direction of the door 10, the gear 46A and the shaft 48 rotate relative to each other. Let

  Thus, in the gear unit 40, when the door 10 is opened, the final gear 46F stops rotating, and when the door 10 is closed, the final gear 46F rotates. Note that a known configuration can be applied to the one-way clutch mechanism provided in the gear 46C, and detailed description thereof is omitted here. In addition, the one-way clutch mechanism is not limited to the gear 46C, and may be provided in any of the gears 46A to 46F. The gear unit 40 is provided in the final stage when the input shaft 30 is rotated in the closing direction of the door 10. Any configuration can be applied as long as the gear 46F rotates.

  As shown in FIGS. 2 and 4, the braking unit 42 includes a rotator 50 and a braking circuit 52 (see FIG. 4). As shown in FIG. 2, the rotator 50 includes a rotor 54 and a stator 56, and a gear 46 </ b> F of the gear unit 40 is connected to a rotor shaft 54 </ b> A of the rotor 54. Thereby, as for the rotator 50 of the braking part 42, when the door 10 is closed, the rotor 54 rotates with the rotational speed according to the rotational speed of the door 10. FIG.

  In the rotor 54, a plurality of pairs of permanent magnets 58N and 58S are attached to a rotor shaft 54A. The stator 56 is provided with a plurality of coils 60. In the rotator 50, when the rotor 54 rotates, an induced electromotive force is generated in each of the coils 60 of the stator 56. As such a rotator 50, synchronous machines, such as a synchronous motor and a synchronous generator, can be used. In the first embodiment, as an example, a stepping motor which is a kind of synchronous motor is used. As shown in FIG. 4, the rotator 50 (stepping motor) applied to the first embodiment is a so-called two-phase motor in which the stator 56 includes coils 60 </ b> A and 60 </ b> B. Hereinafter, the coils 60 </ b> A and 60 </ b> B are collectively referred to as a coil 60.

  As shown in FIG. 4, the braking circuit 52 is provided with a capacitor 62 for each of the coils 60 of the rotator 50. In the braking circuit 52, a closed circuit including the coil 60 and the capacitor 62 is formed by connecting both terminals of the coil 60 with the capacitor 62. A closed circuit refers to a circuit that has no external power input and no external power output. Hereinafter, the closed circuit is referred to as a resonance circuit 64. Moreover, in 1st Embodiment, the coil 60A side and the coil 60B side are set as the equivalent structure, and it demonstrates as the coil 60 below, without distinguishing.

  In each of the resonance circuits 64, the capacitor 62 is charged by generating an induced electromotive force in the coil 60 (coils 60A and 60B). Further, the resonance circuit 64 discharges the electric power charged in the capacitor 62 when the polarity of the induced electromotive force generated in the coil 60 changes. At this time, a back electromotive force is generated in the coil 60 because the resonance circuit 64 is a closed circuit. The counter electromotive force generated in the coil 60 gives a rotational force (torque) in a direction to suppress the rotational speed of the rotor 54 of the rotator 50.

  In the rotator 50, the rotational force input to the rotor 54 from the input shaft 30 exceeds the rotational force (hereinafter referred to as braking torque) that rotates the rotor 54 generated in the coil 60 in the opposite direction. 30 and the rotor 54 rotate. At this time, the rotator 50 suppresses the rotation speed of the input shaft 30 by suppressing the rotation speed of the rotor 54 by the braking torque.

  That is, in the rotator 50, the torque generated in the rotor 54 changes according to the current value i flowing through the coil 60, and when the current value i decreases, the rotational torque decreases and the current value i increases. Rotational torque increases. Accordingly, the torque necessary for rotating the rotor 54 changes according to the current value i, and acts as a braking torque when the rotor 54 is rotated. In the rotator 50, the current value i changes in a cycle corresponding to the rotational speed of the rotor 54. Hereinafter, the average value of the current values will be described as the current value i.

  In general, as shown in FIG. 1B, assuming that the angular velocity when the door 10 is rotated in the closing direction is r (rad / sec) and the width W (m) of the door 10 is, the tip of the door 10 moves in the closing direction. The moving speed v (m / sec) is v = W · r.

  When the door 10 is closed, the input shaft 30 of the door closer 20 attached to the door 10 rotates at a rotational speed corresponding to the movement of the door 10 through the first arm 26 and the second arm 28. Further, the rotor 54 of the rotator 50 provided in the door closer 20 rotates at a rotation speed (the number of rotations per unit time, rpm) corresponding to the rotation speed of the input shaft 30. The braking torque generated in the rotator 50 suppresses the rotational speed of the rotor 54.

  When the rotor 54 of the rotator 50 is to be rotated according to the speed v of the door 10, the rotor 54 of the rotator 50 rotates at a rotation speed (hereinafter referred to as a rotation speed N) suppressed by the braking torque. Thus, the speed v of the door 10 is braked.

  From here, the door closer 20 sets the capacitance C of the capacitor 62 provided in the braking circuit 52 so that a desired braking torque can be obtained at the preset speed v (angular speed r) when the door 10 is closed. ing.

  Below, operation | movement of the door closer 20 and the braking circuit 52 provided in the door closer 20 are demonstrated.

  When the door closer 20 is operated to open the door 10 (rotating operation in the opening direction), the input shaft 30 rotates according to the rotation of the door 10 in the opening direction. In the door closer 20, the spiral spring 44 is tightened as the input shaft 30 rotates in the opening direction of the door 10. As a result, a biasing force that biases the door 10 in the closing direction is stored in the door closer 20.

  Thereafter, the opening operation of the door 10 is finished, and the door closer 20 is released from the door 10 or the closing operation of the door 10, so that the door closer 20 receives the input shaft 30 by the urging force accumulated in the urging portion 38. Rotates in the closing direction of the door 10. Thereby, the door 10 is rotated in the closing direction by the door closer 20 and is automatically closed.

  By the way, the door closer 20 is provided with a rotator 50 at the braking portion 42. When the door 10 is rotated in the opening direction, the door closer 20 stops the rotation of the rotor 54 of the rotator 50. However, when the door 10 rotates in the closing direction, the rotation of the input shaft 30 is performed via the gear unit 40. Is transmitted to the rotor 54 of the rotator 50 and tries to rotate the rotor 54 at a rotation speed corresponding to the speed v in the closing direction of the door 10.

  The braking unit 42 is provided with a braking circuit 52, and a circuit (resonance circuit 64) that is closed by connecting a capacitor 62 to a coil 60 provided in the stator 54 of the rotator 50 is formed in the braking circuit 52. Yes.

  Thus, when the rotor 54 of the rotator 50 rotates, an induced electromotive force is generated in the coil 60 of the rotator 50 according to the rotational speed of the rotor 54, and the induced electromotive force is periodically generated according to the rotation of the rotor 54. The back electromotive force is generated by the change. This counter electromotive force acts as a braking torque that suppresses the rotational force of the rotor 54.

  Accordingly, the rotor 54 of the rotator 50 rotates at the rotational speed N that is braked by the braking torque, and the rotor 54 rotates the input shaft 30 at the rotational speed of the rotor 54, thereby suppressing the rotational speed of the input shaft 30. (The rotational speed of the input shaft 30 is braked). Thereby, the door closer 20 brakes the speed v (angular speed r) of the door 10 when the door 10 connected to the input shaft 30 is closed.

  Here, in the braking circuit 52, a resonance circuit 64 in which a capacitor 62 is connected to the coil 60 is formed as a closed circuit so that the impedance Z changes in accordance with the rotational speed N of the rotor 54. In the resonance circuit 64, the current value i of the coil 60 changes as the impedance Z changes. In the rotator 50, the braking torque also changes as the current value i of the coil 60 changes.

  The resonance circuit 64 includes a coil 60 having an inductance L, a capacitor 62 having an electrostatic capacitance (capacitance) C, and a resistor 66 having a resistance value R including the resistance value of the coil 60 and the like.

  The output impedance Z of the resonance circuit 64 is generally obtained by equation (1). In addition, the phase angle θz of the impedance Z is expressed by equation (2).

The current value i is minimized by minimizing the impedance Z. In order to minimize the current value i, the phase angle θz may be minimized (θz = 0), and the angular frequency ω (resonance angular frequency ω ₀ ) that minimizes the phase angle θz is expressed by the equation (3). can get.

Further, from the angular frequency ω = 2πf, the resonance frequency f ₀ (Hz) that minimizes the phase angle θz is obtained by the equation (4).

Accordingly, by setting the capacitance C of the capacitor 62 so as to obtain the impedance Z that minimizes the phase angle θz, a large braking torque can be obtained at the resonance angular frequency ω ₀ . Further, the capacitance C of the capacitor 62 that minimizes the phase angle θz is the capacitance C that sets the frequency f to the resonance frequency f ₀ in the resonance circuit 64.

The relationship between the frequency f (Hz) of the resonance circuit 64 and the rotational speed N (rpm) of the rotor 54 of the rotator 50 is N = (number of magnets 58N and 58S) where P = the number of poles of the rotor 54. 120 · f) / P. Further, between the door 10 and the rotator 50, the rotor 54 is rotated at a rotational speed N corresponding to the movement of the door 10, the speed increasing ratio of the gear unit 40 (the speed reducing ratio viewed from the rotor 54 side), and the like. .

  Here, the braking torque measurement result with respect to the rotation speed N of the rotator 50 corresponding to the capacitance C of the capacitor 62 is shown. Here, the braking torque is a rotational torque necessary for rotating the rotor 54.

  This measurement uses a two-phase stepping motor having the number of poles P = 100 (N and S poles 50) as the rotator 50 to be measured. The stepping motor to be measured has an inductance L = 1.95 (mH) of each coil (coil 60) (measured at 830 Hz using an LCR meter) and an internal resistance value of 1.9 (Ω). Here, measurement is performed by connecting a resistor having a resistance value of 10 (Ω) to the resonance circuit 64.

  In addition, the measurement uses a drive motor capable of obtaining a rotation speed (rotation speed) corresponding to the drive voltage, and changes the drive voltage of the drive motor to change the rotation speed (rotation speed) of the drive motor.

  The braking torque is obtained by connecting the rotor shaft 54A to be measured and the output shaft (rotor shaft) of the drive motor with a torque cable, and measuring the rotation of the torque cable using a non-contact tachometer. In addition, the measurement of the braking torque is performed for the capacitance C of the capacitor 62 with respect to 20 μF, 30 μF, 40 μF, and 47 μF. As a comparative example, an LR circuit excluding the capacitor 62 is formed.

  As shown in FIG. 5, in the comparative example in which the capacitor 62 is not used, the braking torque increases as the rotational speed N increases. However, the braking torque is saturated at a relatively low rotational speed N, and the braking torque increases. Stop. In the comparative example, the maximum value of the braking torque is also a relatively low value. Furthermore, in the comparative example, a phase shift occurs in the current, so that a saturation state occurs in which the braking torque does not change (increase) even when the rotational speed N increases.

  That is, by short-circuiting both ends of the coil 60 of the rotator 50, an induced electromotive force and a counter electromotive force can be generated. However, the braking torque is saturated at a relatively low rotational speed, and the maximum value of the braking torque is obtained. Is a relatively low value. For this reason, for example, when the speed v of the door 10 suddenly increases, the increase in speed may not be suppressed.

  On the other hand, when the resonance circuit 64 provided with the capacitor 62 is used, the maximum value of the braking torque becomes larger than that of the comparative example. Further, when the capacitor 62 is used, the maximum value of the braking torque increases as the capacitance C of the capacitor 62 decreases.

  Further, when the capacitor 62 is used, the rotational speed at which the braking torque reaches a maximum value changes according to the capacitance C of the capacitor 62, and the maximum value of the braking torque is obtained as the capacitance C decreases. The rotational speed N increases. Further, at a low rotation speed N, the use of the capacitor 62 reduces the braking torque as compared with the comparative example.

  The change characteristic of the braking torque with respect to the rotational speed N of the rotator 50 corresponds to the braking characteristic of the door closer 20, and the resonance circuit 64 using the capacitor 62 is formed. In a region where the braking torque is low and the rotational speed N is high, a large braking torque can be obtained.

  Therefore, the door closer 20 determines the maximum speed in the range of the speed v at which the door 10 is braked and the braking torque at the speed, and if the capacitance C of the capacitor 62 is set based on this, the door closer 20 The door 10 can be closed smoothly by braking the speed v of 10 to a desired state.

As shown in the equation (1), the impedance Z also varies depending on the resistance value R, and as shown in the equation (4), the resonance frequency f ₀ also varies depending on the inductance L of the coil 60. Accordingly, the door closer 20 sets the impedance Z and the resonance frequency f ₀ including the resistance value R and the inductance L of the coil 60 in addition to the capacitance C of the capacitor 62 of the resonance circuit 64, thereby speeding up the door 10. The degree of freedom in setting the braking characteristic with respect to v increases.

[Second Embodiment]
Next, a second embodiment will be described. Note that, in the second embodiment, functional components equivalent to those in the first embodiment described above are given the same reference numerals as those in the first embodiment, and detailed descriptions thereof are omitted.

  FIG. 6 shows an example of the braking unit 70 according to the second embodiment. The braking unit 70 uses a rotator 72 instead of the rotator 50 of the braking unit 42. The braking unit 70 uses a braking circuit 74 instead of the braking circuit 52 of the braking unit 42.

  The rotator 72 uses a three-phase AC motor as an example of a synchronous motor. The stator 56 of the rotator 72 is provided with a U-phase coil 76U, a V-phase coil 76V, and a W-phase coil 76W (hereinafter generically referred to as a coil 76), and the coils 76U, 76V, and 76W are provided. So-called Y connection (star connection) is established.

  The braking circuit 74 includes three capacitors 78, and between the U-phase coil 76 U and the V-phase coil 76 V and between the V-phase coil 76 V and the W-phase coil 76 W of the rotator 72 by the capacitor 78. The U-phase coil 76U and the W-phase coil W are connected to each other (so-called Δ connection).

  Accordingly, the braking circuit 74 includes a closed circuit in which the coil 76U, the coil 76V, and the capacitor 78 are connected, a closed circuit in which the coil 76V, the coil 76W, and the capacitor 78 are connected, and a coil 76U, the coil 76W, and the capacitor. A closed circuit (hereinafter referred to as a resonance circuit) connected to 78 is formed. In each resonance circuit, each coil 76 has a predetermined resistance value, but in FIG. 6, a resistor corresponding to the resistance value of the coil 76 is not shown.

  In the braking unit 70, when the rotor of the rotator 72 is rotated, a braking torque due to the counter electromotive force is generated. In the braking unit 70, the capacitance C of the capacitor 78 of the braking circuit 74 is set so that an appropriate braking torque can be obtained at a desired speed v of the door 10.

  Here, the measurement result of the braking torque with respect to the rotational speed of the rotator 72 corresponding to the capacitance C of the capacitor 78 is shown.

  This measurement uses a three-phase AC motor having the number of poles P = 8 (N and S poles 4) as the rotator 72 to be measured. The three-phase AC motor to be measured has an inductance L = 3.4 (mH) between the coil 76U and the coil 76V, between the coil 76V and the coil 76W, and between the coil 76U and the coil 76W. And the internal resistance is 1.9 (Ω) (measured between the W phase and the U phase).

  Further, the measurement is performed by the same method as in the first embodiment. In addition, the measurement is performed with respect to the capacitance C of the capacitor 78 of 2000 μF, 1500 μF, 1300 μF, and 1000 μF. As a comparative example, a circuit excluding the capacitor 78 (a circuit in which the phases of U, V, and W are short-circuited) is formed.

  As shown in FIG. 7, in the comparative example in which the capacitor 78 is not used, the braking torque increases as the rotational speed N increases. However, the braking torque saturates at a relatively low rotational speed N, and the braking torque increases. The maximum value of the braking torque is also relatively low.

  On the other hand, when the braking circuit 74 provided with the capacitor 78 is used, the maximum value of the braking torque is increased as compared with the comparative example. In addition, when the capacitor 78 is used, the maximum value of the braking torque increases as the capacitance C of the capacitor 78 decreases.

  Furthermore, when the capacitor 78 is used, the rotational speed of the maximum value of the braking torque differs depending on the electrostatic capacity C of the capacitor 78, and the rotational speed at which the maximum value of the braking torque is obtained as the electrostatic capacity C decreases. N increases. Further, at the low rotational speed N, when the capacitor 78 is used, the braking torque is also lower than that of the comparative example.

  In this manner, by forming the braking circuit 74 using the capacitor 78, the braking torque of the rotator 72 is lowered in the region where the rotational speed N is low, and the braking force is increased by the rotator 72 in the region where the rotational speed N is high. Torque can be obtained.

  Therefore, even if the door closer 20 uses the braking unit 70 instead of the braking unit 42, the range of the speed v at which the door 10 is braked and the braking torque in the range are determined, and based on this, the capacitance C of the capacitor 62 is determined. Is set, the door 10 can be smoothly closed by braking the speed v of the door 10 to a desired state.

[Third Embodiment]
Next, a third embodiment will be described. The basic configuration of the third embodiment is the same as that of the first embodiment described above, and the same reference numerals as those of the first embodiment are assigned to the functional parts similar to those of the first embodiment. Detailed description thereof will be omitted.

  FIG. 8 shows an example of the braking unit 80 according to the third embodiment. The braking unit 80 uses a braking circuit 82 instead of the braking circuit 52. The braking circuit 82 uses a resistance variable circuit 84 instead of the resistor 66. The variable resistance circuit 84 includes a rectifier 86, and the rectifier 86 is connected between the coil 60 and the capacitor 62. In FIG. 8, in the resonance circuit 64A, a resistor corresponding to the resistance value of the coil 60 is not shown.

  The rectifier 86 is formed by, for example, a diode 86A being bridge-connected, and outputs a DC voltage. In the variable resistance circuit 84, the output sides of the rectifiers 86 of the coils 60 are connected to each other, and a variable resistor 88 is further connected. The variable resistor 88 receives a positive voltage from one of the rectifiers 86 on one end side and a negative voltage on the other end side.

  In the resistance variable circuit 86 formed in this way, by operating one variable resistor 88, the resistance value R of the resonance circuit 64A of each of the coils 60A and 60B is simultaneously changed to the equivalent resistance value R. be able to.

  As shown in the equations (1) and (2), the impedance Z and the phase difference θz change according to the resistance value R.

  Therefore, the change characteristic of the braking torque of the rotator 50 can be changed by changing the resistance value R. At this time, the resistance variable circuit 86 can change the resistance value R while maintaining a balance between the coil 60A side and the coil 60B side.

[Fourth Embodiment]
Next, a fourth embodiment will be described. The basic configuration of the fourth embodiment is the same as that of the second embodiment described above, and the same reference numerals as those of the second embodiment are assigned to the functional parts similar to those of the second embodiment. Detailed description thereof will be omitted.

  FIG. 9 shows an example of the braking unit 90 according to the fourth embodiment. The braking unit 90 uses a braking circuit 92 instead of the braking circuit 74. In the braking circuit 92, one end of a capacitor 78 is connected to each of the U-phase 76U, the V-phase coil 76V, and the W-phase coil 76W. The braking circuit 92 includes a resistance variable circuit 94, and each of the capacitors 78 is connected to the resistance variable circuit 94. Each coil 76 has a predetermined resistance value, but in FIG. 9, the corresponding resistor is not shown.

  The variable resistance circuit 94 includes a rectifier circuit 96 and a variable resistor 88. The rectifier circuit 96 connects each of the capacitors 78 and both ends of the variable resistor 88 with a diode 96A. In the rectifier circuit 96, the diode 96 </ b> A connected to each of the capacitors 78 has different current directions on one end side and the other end side of the variable resistor 88. A voltage is applied, and a negative voltage is applied to the other end side.

  As a result, the braking circuit 92 has so-called Y connection (star connection) of the three capacitors 78, and each combination of two of the U phase coil 76U, the V phase coil 76V, and the W phase coil 76W. In addition, a closed circuit (resonance circuit) is formed by two capacitors 78 and a variable resistor 88.

  In the resistance variable circuit 94 formed in this way, by operating one variable resistor 88, the resistance value R of each resonance circuit can be simultaneously and equivalently maintained in a balanced state between the resonance circuits. The resistance value R can be changed.

  Further, the braking circuit 90 can change the change characteristic of the braking torque of the rotator 72 by changing the resistance value R of the variable resistor 88.

  In the third and fourth embodiments, the variable resistance value 88 is used. However, when the rotational speed N of the rotor 54 increases and a large braking torque is generated, the current of the variable resistor 88 increases.

  From here, FIG. 10 shows the variable resistance circuit 100 used in place of the variable resistor 88. The variable resistance circuit 100 includes a transistor 102 and a variable resistor 104. In the variable resistance circuit 100, for example, an N-type MOSFET is used as the transistor 102. The transistor 102 has a drain D connected to the positive voltage side of the rectifier 86 or the rectifier circuit 96 and a source S connected to the negative voltage side. The variable resistor 104 has a resistance element connected to the drain D and the source S of the transistor 102, and a slider connected to the gate G of the transistor 102.

  Thereby, the variable resistance circuit 100 changes the resistance value R by operating the position of the slider of the variable resistor 104. At this time, a current flows in the transistor 102 according to the resistance value of the variable resistor 104, and the allowable current of the variable resistance circuit 100 is determined by the allowable current of the transistor 102.

  Therefore, the variable resistance circuit 100 can use a small and small signal (small current) resistor such as a cermet trimmer as the variable resistor 104.

  In addition to the electrical braking function using the rotator 50 or the rotator 72, the braking unit provided in the door closer 20 may have a mechanical braking function such as a friction brake using centrifugal force. As a result, in a region where the rotational speed of the input shaft is low, the braking torque is suppressed, the braking torque is increased as the rotational speed increases, and an extremely large braking torque can be obtained when the rotational speed further increases. be able to.

  The embodiment described above does not limit the present invention. In the present embodiment, the door closer 20 having the door 10 as a braking target has been described as an example. However, the present invention is not limited to a door, and can be applied to a configuration that brakes rotation of an arbitrary braking target. At this time, in the present embodiment, braking is applied to rotation in one direction, ie, the closing direction of the door 10, but the present invention is not limited to this. It can also be configured to apply braking to both the forward direction and the reverse direction of the input shaft. In this case, the one-way clutch mechanism may be omitted.

  Further, the present invention is not limited to a rotating braking target, and can be applied to a braking target that moves linearly, for example. In this case, the moving speed to be braked may be converted into the rotational speed of the input shaft or the rotor shaft.

DESCRIPTION OF SYMBOLS 10 Door 20 Door closer 22 Closer main body 30 Input shaft 38 Energizing part 40 Gear part 42, 70, 80, 90 Braking part 50, 72 Rotator 52, 74, 82, 92 Braking circuit 54 Rotor 56 Stator 60 (60A, 60B) , 76 (76U, 76V, 76W) Coil 62, 78 Capacitor 64, 64A Resonant circuit 66 Resistor 84, 94 Variable resistance circuit 88, 104 Variable resistor 100 Variable resistance circuit

Claims (11)

A rotor connected to a braking target and rotated at a rotational speed according to the moving speed of the braking target, and a stator having a coil that generates an induced electromotive force according to the rotational speed at a period synchronized with the rotation of the rotor. Rotator,
Formed as a closed circuit by the coil and a capacitor connected to the coil, and for braking the movement of the braking target by applying a rotational force that suppresses the rotational speed of the rotor by a counter electromotive force generated in the coil. A braking circuit;
Including braking device.   The braking device according to claim 1, wherein the capacitance of the capacitor is set to maximize a rotational force that suppresses the rotational speed at a preset rotational speed of the rotor.   The braking device according to claim 1 or 2, wherein the capacitance of the capacitor is set so that a resonance frequency of the closed circuit is a frequency corresponding to a preset rotation speed of the rotor.   The braking device according to any one of claims 1 to 3, wherein the capacitance of the capacitor is set such that an impedance of the closed circuit is lowest at a preset rotation speed of the rotor.   The braking device according to any one of claims 1 to 4, further comprising a current adjusting unit that connects the coil and the capacitor and adjusts a current value of the closed circuit. A door that opens and closes the opening;
An input shaft that is rotated in response to rotation in the opening direction and the closing direction of the door;
An urging unit that accumulates an urging force by rotating the input shaft in the opening direction of the door, and that rotates the input shaft in the closing direction of the door by the urging force accumulated;
A rotor coupled to the input shaft and rotated at a rotational speed corresponding to the rotational speed of the input shaft; and a stator having a coil that generates an induced electromotive force according to the rotational speed at a period synchronized with the rotation of the rotor. A rotator with
Formed as a closed circuit by the coil and a capacitor connected to the coil, and for braking the rotation of the input shaft by applying a rotational force that suppresses the rotational speed of the rotor by a counter electromotive force generated in the coil. A braking circuit;
Including door closer.   The door closer according to claim 6, wherein the capacitance of the capacitor is set to maximize a rotational force that suppresses the rotational speed at a preset rotational speed of the rotor.   The door closer according to claim 6 or 8, wherein the capacitance of the capacitor is set so that a resonance frequency of the closed circuit is a frequency corresponding to a preset rotation speed of the rotor. The capacitance of the capacitor was set such that the impedance of the closed circuit was the lowest at a preset rotation speed of the rotor,
The braking device according to any one of claims 6 to 8.   The door closer according to any one of claims 6 to 9, further comprising a current adjusting unit that connects the coil and the capacitor and adjusts a current value of the closed circuit. The speed increasing means which accelerates | stimulates the rotational speed of the said input shaft rotated in the closing direction of the said door, and transmits to the said rotor between the said input shaft and the said rotor of the said rotary device from Claim 6 to Claims. The door closer according to any one of 10.

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