JP2005113965A - Electromagnetic braking unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic braking unit capable of being thin and compact in size for a braked device. <P>SOLUTION: A manual brake release device 70 releasing a braking state of a brake drum 5 in an emergency is assembled in a housing recessed section 74 arranged on a fixed member 3. One end of the manual brake release device 70, in which a release lever 75 is mounted on its end, is located in a housing recessed section 74, and an operating shaft 71 connecting with a brake shoe 11, in which other end is movably penetrated into a through-hole 19 of a core A, is provided in the manual brake release device 70. The release lever 75 is oscillatable on a fulcrum member 77, and moves the operating shaft 71 to a right direction by pushing a nut 76 when oscillating in an arrow A direction by means of traction of a release cable 78. A brake lining 24 is separated from a braking surface 5a of the brake drum 5 by moving the brake shoe 11 in a right direction against a braking spring 13, and releases braking conditions of the brake drum 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to an electromagnetic braking device such as an electromagnetic drum brake having a remotely operated manual braking release device, and more particularly to an electromagnetic braking device suitable for use as a motor brake for an elevator hoist or an industrial robot. It is.

This type of electromagnetic drum brake used as a brake for braking a rotating body such as an elevator hoist or a holding brake for holding the rotating body in a stopped state is used in an emergency (power failure, failure, etc.) A device provided with a manual braking release device that releases a braking state by manual operation is known (for example, see Patent Documents 1 to 5). This type of manual brake release device separates the brake shoe from the braking surface of the brake drum against the brake spring by an external operation without energizing the exciting coil. The applicant has not been able to find prior art documents closely related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in this specification.
JP 2003-176842 A JP 2001-322781 A JP 2001-192192 A JP 2000-232754 A JP 2001-343033 A

  In order to facilitate installation in a narrow storage space, the brake device described in JP-A-2003-176842 has a pair of electromagnetic brake parts made of an internal expansion type corresponding to the inner peripheral surface of the brake drum. The brake drum is configured to be mounted on the mounting member of the elevator hoisting machine with a 180 ° separation in the circumferential direction and brake the brake drum. In addition, this brake device is biased in a direction away from the normal fixed core by a spring opposed to an electromagnet composed of an exciting coil and a fixed core (field core), and a magnetic pole surface of the fixed core across an air gap. A movable iron core (armature), a brake shoe connected to the movable iron core via a connecting member, a brake spring that presses the brake shoe against the braking surface of the brake drum via a lining material, and the like. Projections are provided on both sides of the fixed iron core, and the inner surfaces of these protrusions serve as torque receiving surfaces that receive the rotational torque of the brake shoe. In addition, a pin is protruded from the projecting portion, and a lever is swingably attached to the pin, and the lever is manually operated in an emergency to press the movable iron core against the brake spring to separate it from the brake drum. Thus, the braking state of the brake drum is released.

  The elevator hoist described in JP-A-2001-322781 has a saddle-like rotating body (brake drum) in order to reduce the outer shape of the hoist and enable installation in a narrow storage space. A brake for braking the braking surface is disposed in the recess of the bowl-shaped rotating body. The brake release mechanism for releasing the braking state by the brake includes a release cable, a release brake arm, a release cable mounting plate, and the like, and is externally attached to a support plate of the elevator hoist.

  The reduction gear with a motor described in the Japanese Patent Application Laid-Open No. 2001-192192 supports both ends of the input shaft of the reduction device and supports the rotation shaft by coupling the rotation shaft of the drive motor to the input shaft. Therefore, the length of the entire apparatus in the axial direction is reduced at a low cost. The brake release mechanism that separates the brake shoe from the brake drum in the event of a failure or the like includes a rotatable release lever provided on the surface of a ring-shaped fixing member, a wire having one end connected to the release lever, a brake shoe And an arcuate plate connected to each other, and when the release lever is rotated by the wire, the release lever presses the plate and separates the brake shoe from the brake drum.

  A drive motor with a radial braking electromagnetic brake described in Japanese Patent Laid-Open No. 2000-232754 includes a fixed portion and a rotating portion provided rotatably with respect to the fixed portion, and the fixed portion is configured with a casing and an electromagnetic brake. It consists of a main body. A rotating shaft rotatably supported on the casing via a bearing; a rotor of an AC servomotor having a cylindrical portion coaxial with the rotating shaft; and a circle connecting the rotating shaft and the rotor. It is comprised with the plate-shaped rotation connection member. Further, a plurality of armatures are provided on the outer periphery of the electromagnetic brake body so as to be movable in the radial direction, pressed against the inner surface of the rotor by a coil spring, and the rotor is separated from the rotor by energizing the brake exciting coil. The brake is released. A manual brake release mechanism for releasing the braking of the rotor includes a release rope, a segment ring, a release handle, a connecting bolt for connecting the segment ring and the armature, and the like, and is attached to the surface of the rotating portion.

  The manual brake release mechanism of the drive motor with a radial brake electromagnetic brake described in Japanese Patent Laid-Open No. 2001-343033 is substantially the same as the manual brake release mechanism described in Japanese Patent Laid-Open No. 2000-232754. The difference is that instead of rotating the armature provided on the outer periphery of the electromagnetic brake main body, the armature is translated in the radial direction by the guide member.

In the brake release device of the brake device described in JP-A-2003-176842, a swingable lever is attached to a pin protruding from a protruding portion of a fixed iron core so as to extend in the axial direction of the brake drum. In order to reduce the operating force of this lever, the operating point and the force point (release cable mounting portion) and the distance between the fulcrum (pin) of the lever and the operating point (armature pressing portion) It is necessary to increase the lever ratio by increasing the distance between the two.
However, when the lever ratio is increased, as a result, the lever becomes longer and protrudes to the outside of the brake device, so that there is a problem that the entire device is enlarged.

  The elevator hoist described in JP-A-2001-322781 is also described in JP-A-2003-176842 because the brake release mechanism is externally attached to the support plate of the elevator hoist. As with the brake device, there is a problem that the entire device becomes large.

  The reduction gear with a motor described in Japanese Patent Laid-Open No. 2001-192192 has a problem that the size in the thickness direction of the entire device increases and the size increases because the brake release mechanism is attached to the surface of the fixing member. It was.

  The drive motor with a radial brake electromagnetic brake described in Japanese Patent Laid-Open No. 2000-232754 and Japanese Patent Laid-Open No. 2001-343033 has a manual brake release mechanism attached to the surface of the rotating portion. Similar to the reduction gear device with a motor described in the publication, there is a problem that the size of the entire device increases in size in the thickness direction and increases in size.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide an electromagnetic braking device that enables downsizing of the braked device.

  In order to achieve the above object, a first invention is an electromagnetic braking device for braking a braked body, a field core fixed to a fixing member of the braked device so as to face a braking surface of the braked body; A brake shoe having a brake lining and an armature and provided in the field core so as to be movable in a radial direction of the braked body, and the brake lining by urging the brake shoe in a direction away from the field core A brake spring that presses against the braking surface of the braked body, and a manual brake release device that releases the braking state of the braked body. And an operation shaft connected to the brake shoe through the through hole provided in the field core at the other end so as to freely advance and retract. A release lever mounted pivotably at one end of the fulcrum member forms a fulcrum for this release lever, which is constituted by a release cable for oscillating the release lever.

  According to a second invention, in the first invention, the brake spring is mounted in a through hole through which the release lever of the field core passes.

In the present invention, one end side of the operating shaft is positioned in the housing recess of the fixing member, a release lever is attached, and the other end side is pierced through a through-hole provided in the field core so as to be able to advance and retract. Therefore, there are few portions which protrude outside the braked device, and the size of the braked device in the thickness direction can be reduced and the size can be reduced.
In addition, since the operating shaft and the braking spring are accommodated in the through hole in common, it is not necessary to form a hole for the braking spring and a hole for the operating shaft separately. It will not be long or large.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
As an embodiment of the present invention, the electromagnetic drum brake shown in FIGS. 1 to 11 has been developed as a brake for holding an elevator hoisting machine and an emergency braking brake. FIG. 1 is a front view of an elevator hoisting machine, and shows a state in which two electromagnetic drum brakes are incorporated. 2 is a cross-sectional view taken along line II-II in FIG. 1, FIG. 3 is a front view showing a part of the left electromagnetic drum brake, FIG. 4 is a plan view of the electromagnetic drum brake, and FIG. FIG. 6 is a sectional view of the electromagnetic drum brake, and FIG. 7 is an enlarged sectional view of the main part of FIG. 8A, 8B, and 8C are a plan view, a front view, and a right side view of the guide member, and FIG. 9 is a view for explaining the operation of the manual brake releasing device.

  In these drawings, an elevator hoisting machine 1 constituting a braked device includes a housing 2 and a fixing member 3 fixed to the housing 2 by a plurality of bolts 4 so as to cover the front opening of the housing 2. A cylindrical brake drum (braking body) 5 is incorporated in the housing 2, and a pair of left and right electromagnetic drum brakes LB and RB are incorporated in the fixing member 3.

  The brake drum 5 is attached to a rotating shaft 6 (FIG. 2, detailed illustration is omitted), the inner peripheral surface forms a braking surface 5a, and a plurality of magnets 7 are arranged on the outer peripheral surface at a predetermined interval in the circumferential direction. An electric motor 9 for rotating the brake drum 5 is constituted by the magnet 7 and the fixed winding 8 fixed to the inner peripheral surface of the housing 2. The rotating shaft 6 is rotatably supported by the housing 2 and the fixing member 3.

  The pair of electromagnetic drum brakes LB, RB is incorporated inside the brake drum 5 in a state of being separated by 180 degrees in the circumferential direction of the braking surface 5a, thereby forming an internal expansion type electromagnetic drum brake. The left electromagnetic drum brake LB and the right electromagnetic drum brake RB have the same structure, but are different in that they are mounted symmetrically with respect to the fixing member 3. Now, the configuration and operation of the left electromagnetic drum brake LB will be mainly described, and the right electromagnetic drum brake RB will be denoted by the same reference numerals with respect to the same components and parts, and the description thereof will be omitted.

  In FIG. 6, the electromagnetic drum brake LB includes a pair of brakes including a field core 10, a brake shoe 11, an armature 12, and a compression coil spring elastically mounted between the field core 10 and the brake shoe 11. It consists of a spring 13 or the like.

  The field core 10 is formed by machining a carbon steel material for machine structure to have a substantially rectangular shape in plan view and a flat shape, and both ends thereof are fixed by two bolts 15 (see FIG. 3). It has a core 10 </ b> A fixed to the member 3. The core 10A forms a prismatic inner pole portion 10a at the center, and a coil housing portion 20 is formed around the inner pole portion 10a. The coil receiving portion 20 is formed of an annular recess opened on the surface on the armature 12 side. Has been.

  Further, at both ends in the longitudinal direction of the core 10A, support portions 10c having a width narrower than that of the inner pole portion 10a are formed, respectively, and the question portion between the support portion 10c and the coil housing portion 20 is outside. The pole part 10b is formed. Further, the inner pole portion 10a and the outer pole portion 10b have the same width and form a magnetic pole surface 16 whose surface facing the armature 12 is the same plane. In addition, a silencer member such as rubber or felt (not shown) is fixed to a part of the magnetic pole face 16 so as not to generate a sound when the armature 12 is magnetically attracted to the core 10A.

  A bottomed pin hole 18 and a stepped through hole 19 are formed in the armature 12 side surface of each support portion 10c of the core 10A. A guide pin 21 is implanted in the pin hole 18, and the brake spring 13 is elastically mounted in the stepped through hole 19, and an operation shaft 71 described later passes therethrough. The tip of the guide pin 21 protrudes outside from the pin hole 18 and is slidably inserted into a guide hole 22 formed in the leg portion 11b of the brake shoe 11, whereby the brake shoe 11 is inserted into the core 10A. On the other hand, it is supported so as to be able to approach and separate.

  The brake shoe 11 is formed in a substantially rectangular shape in plan view by forging a carbon steel material for machine structure, and forms a flat shoe body 11a at the center in the longitudinal direction. A brake lining 24 is detachably attached to the outer surface facing the 5a with two bolts 26 via a pad 25. In addition, a pair of leg portions 11b each having a tip portion extending on both sides of the core 10A are integrally extended at both ends of the shoe main body 11a. The leg portion 11b is formed so as to be curved in a substantially arc shape when viewed from the side, so that the distal end surface 28 faces the support portion 10c of the core 10A in a substantially parallel manner with an appropriate interval. Further, the guide hole 22 into which the tip end portion of the guide pin 21 is slidably inserted, and the recess 30 into which the brake spring 13 and one end portion of the operating shaft 71 are inserted are formed on the tip surface 28. 10A pin hole 18 and stepped through hole 19 are formed so as to face each other. The brake spring 13 is elastically mounted in the through hole 19 and the recess 30 to urge the brake shoe 11 in a direction away from the core 10 </ b> A, and the brake lining 24 is moved to the braking surface 5 a of the brake drum 5. Is pressed against. The guide hole 22 is press-fitted with a bush (not shown) in which a coating layer of a synthetic resin material having a low friction coefficient and good wear resistance is formed on the inner peripheral surface. It is easy to slide.

  Similarly, the armature 12 is formed in a substantially rectangular shape in plan view by machining a carbon steel material for machine structure, and in a space 31 formed between the magnetic pole surface 16 of the core 10A and the brake shoe 11. Contained. The magnetic attracting surface 17 of the armature 12 faces the magnetic pole surface 16 of the core 10A to form an air gap G. The air gap G is about 0.2 mm and can be adjusted by the interval adjusting means 33 described later, but is set sufficiently smaller than the gap between the support portion 10c and the leg portion 11b. Such an armature 12 is mechanically connected to the shoe body 11a of the brake shoe 11 via two distance adjusting means 33.

  The gap adjusting means 33 includes a screw hole 34 formed near the end of the armature 12, an adjustment bolt 36 screwed into a screw hole 35 formed in the shoe body 11a corresponding to the screw hole 34, and the adjustment. It consists of two nuts 37a and 37b that are screwed into the bolt 36. The adjustment bolt 36 has a right-hand thread portion 36a on one end side, a left-hand thread portion 36b on the other end side, and a rotation operation portion 36c integrally provided at the center portion. According to such a gap adjusting means 33, when the adjusting bolt 36 is rotated after loosening the pair of nuts 37 a and 37 b, the armature 12 moves in a direction toward or away from the brake shoe 11. The air gap G between 10A and the armature 12 can be adjusted. After the adjustment, the two nuts 37a and 37b may be tightened and fixed to the brake shoe 11 and the armature 12, respectively.

  An exciting coil 39 that constitutes an electromagnet together with the core 10A is housed in the coil housing portion 20 of the core 10A. When the exciting coil 39 is energized by energization, the armature 12 is opposed to the braking spring 13 to the core 10A side. The magnetic attraction surface 17 is in close contact with the magnetic pole surface 16 of the core 10A. The exciting coil 39 is fitted into the coil housing part 20 and is hardened with an insulating resin.

  Between the core 10 </ b> A and the armature 12, a release holding means 40 and a pressing force adjusting means 41 composed of a pair are further incorporated.

  6 and 7, the release holding means 40 passes through a through hole 42 formed at the center in the longitudinal direction of the armature 12, and one end portion is screwed into a screw hole 43 formed at the center of the core 10A. 44 and a nut 45 that is screwed into the other end of the release bolt 44 and abuts against the surface of the armature 12 opposite to the core 10A. The nut 45 is attached to the release bolt 44 and presses the armature 12 toward the core 10A until the electromagnetic drum brake LB is assembled into the brake drum 5, thereby causing the magnetic attracting surface 17 to be the magnetic pole surface of the field core 10. The armature 12 can be moved forward and backward with respect to the release bolt 44 by being removed from the release bolt 44 after the electromagnetic drum brake LB is incorporated in the brake drum 5.

  The pressing force adjusting means 41 is elastically mounted in a pressing bolt 49 screwed into a screw hole 48 formed in the armature 12, a nut 50 screwed into the pressing bolt 49, and a spring hole 51 formed in the core 10A. And a spring receiving ring 53 that is housed in the spring hole 51 and is positioned between the pressing spring 52 and the pressing bolt 49. In such a pressing force adjusting means 41, when the nut 50 is loosened and the pressing bolt 49 is rotated in the tightening direction or the loosening direction, the resilience of the pressing spring 52 changes, so that the brake lining 24 by the braking spring 13 changes. The pressing force against the brake drum 5 can be finely adjusted.

  1 and 3, a pair of motion detection means 60 for detecting the motion of each of the electromagnetic drum brakes LB and RB is attached to the fixing member 3 of the elevator hoist 1. The motion detection means 60 can be adjusted in position to the armature 12 and the limit switch 61 fixed to the side surface of the support portion 10c of the core 10A, the switch arm 62 pivotally supported on the side surface of the inner pole portion 10a. When the armature 12 is magnetically attracted to the field core 10 by energization excitation to the excitation coil 39 and braking of the brake drum 5 by the brake lining 24 is released, the detection plate 63 is One end of the switch arm 62 is pressed, whereby the switch arm 62 rotates clockwise around the rotation shaft 65 in FIG. 3, thereby pressing the actuator 61a of the limit switch 61 and operating the switch 60. It is configured to let you. When it is detected by the signal from the limit switch 60 that braking of the brake drum 5 by the electromagnetic drum brake LB is released, the drive motor is driven to rotate the brake drum 5.

  Further, the fixing member 3 of the elevator hoist 1 is provided with a manual braking release device 70 that releases the braking state of the brake drum 5 when manually operated in an emergency. As shown in FIGS. 1 and 3, the manual brake release device 70 is provided in a total of four pairs, one for each electromagnetic drum brake LB, RB, and is provided symmetrically at both ends of each core 10A. It has been. More specifically, the manual brake release device 70 has the operating shaft 71 that passes through the stepped through hole 19 formed in the support portion 10c of the core 10A. One end of the operating shaft 71 is positioned in a housing recess 74 formed on the surface of the fixing member 3 through a through hole 73 formed in the side wall 72 of the fixing member 3. On the other hand, the other end is inserted into the recess 30 of the brake shoe 11 through the through hole 19 of the core 10A, and is screwed into a screw hole formed on the bottom surface of the recess 30 to thereby fit the brake shoe 11. It is connected. Further, at the projecting end portion of the operating shaft 71 protruding into the storage recess 74, the release lever 75 is inclined with respect to the axis of the operating shaft 71 (in the direction of arrows AB in FIG. 11 (in the circumferential direction), and is prevented from falling off from the operating shaft 71 by a nut 76. Further, the release lever 75 is located in the storage recess 74, and a portion close to the operating shaft 71 on the surface facing the side wall portion 72 is supported by a fulcrum member 77 so as to be swingable. One end of a release cable 78 is connected to an end (action point) opposite to the operating shaft 71 side. The fulcrum member 77 is positioned in the storage recess 74 by projecting close to the operating shaft 71 on the inner side of the side wall portion 72, and constitutes a fulcrum when the release lever 75 is swung. Yes. As shown in FIG. 1, the release cable 78 is led to an appropriate location that can be remotely operated along the surfaces of the fixing member 3 and the housing 2.

Here, in the present embodiment, two shafts formed by dividing the operating shaft 71 are connected by screwing. However, the present invention is not limited to this and is formed by a single shaft. Also good.
1 and 3, the release levers 75 of the pair of left and right manual brake release devices 70, 70 located above are connected to each other by a single release cable 78, and a pair of left and right manual brakes located similarly below. The release levers 75 of the release devices 70 and 70 are connected by a single release cable 78, and the two release levers 75 connected by the release cable 78 are swung in the same direction in conjunction with a guide member 90 shown in FIG. An example configured to do this is shown. Further, in order to obtain a smooth swing operation of the release lever 75, the positions of the fulcrum members 77, 77 that are the swing support points of the left and right release levers 75, 75 are shifted in the longitudinal direction of the release lever 75. As the release cable 78, a flexible cable including an outer tube 78A and a core wire 78B is used.

  In the elevator hoisting machine 1 having such a structure, the left electromagnetic drum brake LB is brake brake 11 by the pressing force of the braking spring 13 and the pressing spring 52 when the energization to the exciting coil 39 is cut off. By pressing the brake lining 24 against the braking surface 5a of the brake drum 5, the brake drum 5 is braked and held in a stopped state. In this state, when the exciting coil 39 is energized and energized, the armature 12 is magnetically attracted to the core 10A against the braking spring 13 and the pressing spring 52, and the magnetic attracting surface 17 is magnetically attracted to the magnetic pole surface 16 of the core 10A. . Along with this, the brake shoe 11 also moves together with the armature 12 toward the core 10 </ b> A side to separate the brake lining 24 from the braking surface 5 a of the brake drum 5. Accordingly, the brake drum 5 is released from the braking state by the electromagnetic drum brake LB and becomes rotatable. When the motion detection means 60 detects the movement of the armature 12, the drive motor is driven based on the detection signal to rotate the brake drum 5, thereby raising and lowering the elevator car. Needless to say, the right electromagnetic drum brake RB also operates in conjunction with the left electromagnetic drum brake LB.

  In order to stop raising / lowering the elevator car, the drive motor is stopped and the energization to the exciting coil 39 is cut off. When the current is turned off and demagnetized, the armature 12 and the brake shoe 11 move by the elastic force of the braking spring 13 and the pressing spring 52 to return to their original positions, and press the brake lining 24 against the braking surface 5a of the brake drum 5. . Therefore, the brake drum 5 is braked and stopped.

  When an abnormal situation such as a power failure occurs, the drive motor stops, the excitation coil 39 is demagnetized, and the elevator car stops at a position deviating from a predetermined landing position. At the same time, all four manual brake releasing devices 70 are operated to release the braking state of the brake drum 5. That is, in FIGS. 3 and 9, when the upper release cable 78 is pulled, the release lever 75 of the upper left manual brake release device 70 swings in the direction of arrow A with the fulcrum member 77 as the swing fulcrum, and the nut 76. Press. For this reason, the operating shaft 71 moves to the right. At this time, the upper right manual brake release device 70 also operates in conjunction with the upper left manual brake release device 70 to separate the brake lining 24 of the right electromagnetic drum brake RB from the braking surface 5 a of the brake drum 5. Similarly, when the lower release cable 78 is pulled leftward in FIG. 3, the release lever 75 of the lower left manual brake release device 70 swings in the arrow direction with the fulcrum member 77 as the swing fulcrum and presses the nut 76. Then, the operating shaft 71 is moved to the right. As a result, the brake shoe 11 of the left electromagnetic drum brake LB moves parallel to the right against the braking spring 13 and the pressing spring 52 to separate the brake lining 24 from the braking surface 5 a of the brake drum 5. At this time, the lower right manual brake release device 70 is also operated in conjunction with the lower left manual brake release device 70 to separate the brake lining 24 of the right electromagnetic drum brake RB from the braking surface 5 a of the brake drum 5. Accordingly, braking of the brake drum 5 is released, and in this state, the car is raised and lowered by the weight of the car and stopped at a predetermined landing position, so that passengers inside the car are rescued.

According to the electromagnetic drum brakes LB and RB of the elevator hoisting machine 1 having such a structure, the manual brake releasing device 70 is incorporated in the housing recess 74 formed in the fixed member 3, and the operating shaft 71 is formed in the core 10A. Since it penetrates through the through hole 19 and is connected to the brake shoe 11, only the tip of the release lever 75 and the release cable 78 need to protrude outside the housing recess 74, and the other components are the elevator hoisting machine. Therefore, the elevator hoist 1 can be reduced in thickness and size.
Further, since the brake spring 13 is housed in the through hole 19 and the operating shaft 75 is penetrated, it is not necessary to separately form the through hole for the brake spring and the through hole for the operating shaft, and the core 10A can be manufactured. Easy and downsizing is possible.
Furthermore, if the lever member 77 is moved closer to the operating shaft 71 and the lever ratio of the release lever 75 is increased, the operating shaft 71 can be moved with a small operating force without increasing the release lever 75.

FIG. 10 is a cross-sectional view of a main part showing another embodiment of the manual brake releasing device.
In this embodiment, the upper left and upper right manual brake release devices 70 are arranged symmetrically and are operated independently by two release cables 78. In this case, since the pulling directions of the release levers 78 are reversed left and right, the swing directions of the two release levers 75 and 75 are also reversed.

FIG. 11 is a cross-sectional view of a main part showing still another embodiment of the manual brake releasing device.
This embodiment is the same as the embodiment shown in FIG. 9 in that the upper left hand brake release device 70 and the upper right hand brake release device 70 are operated by a single release cable 78. The difference is that one end of the core wire 78B of the release cable 78 is inserted into a cable insertion hole 100 provided at the distal end of the release lever 75 of the right hand manual brake release device 70, and a ball 101 for preventing the removal from the protruding end. And the two fulcrum members 77 and 77 are provided at symmetrical positions.

  Even in such a structure, as in the embodiment shown in FIG. 9, the left and right release levers 75 can be simultaneously swung in the circumferential direction of the brake drum by a single release cable 78.

In the above-described embodiment, the example applied to the electromagnetic drum brake used as the motor brake of the elevator hoist 1 has been described. However, the electromagnetic braking device according to the present invention includes a crane, an escalator, an industrial robot, and the like. It can also be used as a motor brake.
Further, as an embodiment of the present invention, an internal expansion type electromagnetic drum brake in which a convex arc-shaped brake lining 24 is attached to the brake shoe 11 has been described, but the present invention is not limited to this, and by changing the shape of the brake lining 24, It can also be used as an electromagnetic drum brake that brakes the outer peripheral surface of the cylindrical portion of the brake drum 5 or an electromagnetic disk brake that brakes the side surface of a disc-shaped brake disc (braking body).
Further, as an embodiment of the present invention, the brake shoe 11 having a structure in which the pad 25 (see FIG. 6) of the brake lining 24 is detachably attached to the shoe main body 11a of the brake shoe 11 by the two bolts 26 is described. The electromagnetic drum brake according to the present invention may incorporate the brake shoe 11 having a structure in which the brake lining 24 is directly attached to the shoe main body 11a.

It is a front view of the hoisting machine for elevators. It is the II-II sectional view taken on the line of FIG. It is a front view showing a part of the left electromagnetic drum brake in cross section. It is a top view of the electromagnetic drum brake. It is a bottom view of the electromagnetic drum brake. It is sectional drawing of the electromagnetic drum brake. It is an expanded sectional view of the principal part of FIG. (A), (b), (c) is the top view of a guide member, a front view, and a right view. It is a figure for demonstrating an effect | action of a manual brake release apparatus. It is sectional drawing of the principal part which shows other embodiment of a manual brake release apparatus. It is sectional drawing of the principal part which shows further another embodiment of a manual brake release apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Elevator hoisting machine, 2 ... Housing, 3 ... Fixing member, 5 ... Brake drum, 5a ... Braking surface, 10 ... Field core, 10A ... Core, 11 ... Brake shoe, 12 ... Armature, 13 ... Brake spring, DESCRIPTION OF SYMBOLS 19 ... Through-hole, 24 ... Brake lining, 39 ... Excitation coil, 70 ... Manual brake release apparatus, 71 ... Actuation shaft, 74 ... Storage recessed part, 75 ... Release lever, 77 ... Supporting member, 78 ... Release cable.

Claims (2)

In an electromagnetic braking device that brakes a braked body,
A field core fixed to the fixed member of the braked device so as to face the braking surface of the braked body;
A brake shoe having a brake lining and an armature and provided in the field core so as to be movable in a radial direction of the braked body;
A braking spring that presses the brake lining against the braking surface of the braked body by urging the brake shoe away from the field core;
A manual braking release device for releasing the braking state of the braked body,
An operating shaft connected to the brake shoe through the manual brake release device, one end side of which is located in a storage recess formed in the fixing member, and the other end side of the manual brake release device is movably advanced and retracted through a through hole provided in the field core; A release lever that is swingably attached to one end of the operating shaft, a fulcrum member that forms a swing fulcrum of the release lever, and a release cable that swings the release lever. Electromagnetic braking device. The electromagnetic braking device according to claim 1, wherein
The electromagnetic brake device, wherein the brake spring is mounted in a through hole through which the release lever of the field core passes.

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