JPH10318293A - Manual release mechanism for deenergisation operation electromagnetic brake/clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manual release mechanism to use a low price material and an article on a market, eliminate a need for an operation lever and a release member of complicated structure and a coil spring to operate the members described above, and functionally select a range, extending from the small part of a cam plate to a large part, and causing it to form an operation point through simplification of constitution. SOLUTION: The notch part 15'b, cut below a neck, of a manual release cam 15' is screwed in the upper surface of a yoke 2, serving as a brake body, with the notch part pointing to the armature 8 side and the manual release cam exposed to the upper surface of the yoke 2. A contact point 16'e with a drive coupling disc 16' is inserted in the notch part 15'b and brought into a normal operation state. To release an electromagnetic brake/clutch in a braked state through the force of a spring due to service interruption, contact points 16'e is dislocated from the notch part 15'b and pushed out to the outside when a manual release cam 15' is rotated by a hand, the armature 8 is attracted to the yoke 2 side against the spring 12, and brake is released.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manual release mechanism in a non-excited operation (also referred to as negative operation) electromagnetic brake / clutch for manually braking or releasing a clutch in the event of a power failure or the like.

[0002]

2. Description of the Related Art Typical prior art as a conventional manual release mechanism in a non-excited operation electromagnetic brake / clutch is disclosed in Japanese Utility Model Laid-Open No. 60-23329 and Japanese Utility Model Laid-Open No. 3-49432. The outline of the invention disclosed in Japanese Utility Model Laid-Open No. 60-23329 as prior art 1 is as follows.
This is shown in FIGS. 4, 5 and 6. In these figures,
A pressure receiving plate 22 is fixed via a collar 23 in front of the field core 21 on the right side in the drawing.
The armature 25 magnetically attracted to the front surface 21a of the armature is movable in the axial direction with the collar 23 as a guide,
Flange 21 at rear end of center hole 26 of field core 21
It receives the pressing force of the compression coil spring 27 whose one end abuts on b, and is constantly pressed in the direction of the pressure receiving plate 22. Friction plate 28
Is disposed between the pressure receiving plate 22 and the armature 25,
It is configured to be able to rotate integrally with the hub 29 fixed to the braked rotation member and to rotate in the axial direction. The field core 2
The 1 is built electromagnetic coil 30, a voltage is applied armature 25 is magnetically attracted to the field core 21, the gap c ₃ is zero.

[0005] A semicircular operating rod 31 is attached to the field core 21 so as to surround the upper semicircular portion in FIG. 5, and both ends of the field core 21 are arranged as shown in FIGS. 5 and 6.
1 are mounted on both left and right sides in the radial direction by trunnion-shaped shafts 32, 32 so as to be able to pivot up and down, and claw portions 33, 33 which can be freely engaged with the armature 25 are provided at both ends thereof.
Further, a bent portion 34 protruding outward (upward in FIG. 6) in the radial direction of the operating rod 31 is formed, and a gripping piece 35 that is manually gripped and operated above the bent portion 34 is integrally fixed. . 4 and 5, an inward projection 36 is formed on the radially inner surface of the bent portion 34, and one end of the spring 37 is fitted into the recess 21c on the outer surface of the field core 21.
The outer end of the operating rod 31 is hooked on the protrusion 36 to maintain the standing posture of the operating rod 31. When no voltage is applied to the electromagnetic coil 30 and the armature 25 is not excited, the armature 25 is pushed by the compression coil spring 27 to press the friction plate 28 against the pressure receiving plate 22 to prevent the rotation of the hub 29, and to apply a voltage to the electromagnetic coil 30. Is applied, the armature 25 is magnetically attracted to the field core 21, the friction plate 28 is released, and the restraint on the hub 29 is released. In the case of a power outage or the like, the armature 25 clamps the friction plate 28, so that the armature 25 is manually operated.
May need to be pulled back. In this case, by holding the gripping piece 35 by hand and tilting the operating rod 31 forward in the figure as shown in FIG. 6, the claw portions 33 of the operating rod 31 are engaged with the armature 25, and the armature 25 is The armature 25 is separated because the armature 25 is pulled back in the direction of the field core 21, the hub 29 is free, and the rotation member to be braked can freely rotate.

Further, Japanese Utility Model Application Laid-Open No. 3-49 as prior art 2 is disclosed.
FIGS. 7A and 7B disclose the structure disclosed in Japanese Patent Publication No.
As shown in FIG. 5, the armature 48 is attracted by the excitation of the electromagnetic coil 44 against the resilience of the braking spring 52, and the armature 48 and the side plate 45 release the clamping of the shaft side member to release the braking of the shaft. In a negative-acting electromagnetic brake, a release plate formed of a plate material is provided, and one end of the release plate is pivotally supported on the yoke side, and the rocking pushes the armature to the release plate to separate it from the shaft-side member. And a pressing portion for causing the pressing portion to be provided. FIG. 7A and FIG.
This will be briefly described with reference to FIG. In FIG. 7A, a yoke 43 of an electromagnetic brake in which an electromagnetic coil 44 is provided is fixed to the housing 41, and a predetermined space is formed between the side plate 45 and the yoke 43 by a spacer 47. An annular armature 48 is interposed in this space, and rotation is restricted by sliding a plurality of holes provided on the outer periphery of the armature 48 with the spacer 47, and sliding is guided.

[0005] A shaft 49 is pivotally supported by the housing 41, and a hub 50 is fixed to the tip of the shaft 49. Reference numeral 51 denotes a lining, which is slidably fitted on the outer periphery in the radial direction of the hub 50, and has friction surfaces formed on both the inner and outer surfaces in the axial direction to contact the outer peripheral surface of the armature 48 and the inner peripheral surface of the side plate 45. , Armature 48 has an inner hole 49 at the center of yoke 43.
The lining 51 is pressed against the friction surface 51a of the lining 51 by the braking spring 52 interposed therebetween. A predetermined space is formed between the side plate 45 and the yoke 43 by a spacer 47 externally fitted to a screw portion of a bolt 46, and an annular armature 48 is formed in this space in an axial direction. The rotation is regulated and the sliding is guided by frictionally engaging a plurality of holes provided on the outer periphery of the inner surface of the spacer with the inner surface of the spacer so as to face the magnetic attraction surface 43b and the spacer 47. I have. A hub 50 is fixed to a free end of the shaft 49, and 51 is a lining as a shaft side member interposed between the armature 48 and the side plate 45,
The outer peripheral surface of the hub 50 is slidably fitted to the outer peripheral surface of the hub 50, and friction surfaces are formed on both surfaces thereof so as to contact the axially outer surface of the armature 48 and the axially inner surface of the side plate 45.

The armature 48 includes the braking spring 52
As a result, a chamfered portion 43c is formed on both side surfaces (the front and back surfaces of the paper in FIG. 7) of the yoke 43, and the entire surface is denoted by reference numeral 53 while holding the two-sided chamfered portion 43c. The end of the release plate is pin 54
, So that it is pivotally attached. This release plate 5
3 includes, as shown in FIG. 7 (B), an annular portion 53a, an inverted L-shaped operating portion 53b projecting from the upper end thereof, and a pair of side plates 53c projecting axially inward when assembled. The end portion of the side plate 53 c is formed integrally with the chamfered portion 43 of the yoke 43 as described above.
c is rotatably connected to a pin 54 by a pin 54. An armature 4 is provided at the upper end of the side plate 53c by its rotation.
A pressing portion 53d is formed to press 8 and separate it from contact with the lining 51. This release plate 5
3 is stamped into a plate shape by press working, and is formed by bending an upper end portion and a side plate 53c. Further, a pin 55 implanted in the side plate 45 is inserted into a pin hole 53e of the release plate 53. On the pin 55, a compression coil spring 56 which resiliently releases the release plate 53 and returns it to the upright state shown in the drawing. Is interposed. 53f, 53g
Is a notch formed so as to avoid the bolt 46.

When the electromagnetic coil 44 is excited in the state shown in FIG. 7A, a magnetic flux is generated and flows through the yoke 43 and the armature 48. The armature 48 is attracted to the magnetic attraction surface 43b of the yoke 43 against the elastic force of the braking spring 52, and the lining 51 is released from the pressure contact and becomes rotatable. When the shaft 49 is driven, the shaft 49 passes through the hub 50. And rotates with the lining 51. When the shaft 49 is released from this state and the electromagnetic coil 44 is demagnetized, the armature 48 is separated from the magnetic attraction surface 43 b of the yoke 43 by the elastic force of the braking spring 52 and pressed against the friction surface of the lining 51. Therefore, the rotation of the lining 51 is braked, and the hub 50 is rotated.
Stops, and the shaft 49 also stops. When the rotation of the shaft 49 is braked in this manner, when manually releasing the braking of the shaft 49, the upper end of the release plate 53 is pulled by hand, or the release plate 53 is pulled by remote control to release the release plate 53. When the armature 48 is rotated counterclockwise in the figure, the pressing portion 53d pushes the armature 48 inward, so that the armature 48 moves toward the magnetic attraction surface 43b against the elastic force of the braking spring 52 as shown in F. And armature 48 and side plate 45
Is released, and the braking of the shaft 49 is released.

[0008]

The above prior arts 1 and 2
All of these use complicated operating members such as springs, operating rods and release plates, and use the above-mentioned springs to operate them. There has been a need for a manual release mechanism that is simple, inexpensive to manufacture and assemble, and yet operates reliably.

[0009]

SUMMARY OF THE INVENTION A manual release mechanism for braking or releasing a non-excited electromagnetic brake / clutch according to the present invention basically utilizes a plate cam to manually rotate a cam shaft. By rotating the cam plate rotating coaxially with the camshaft by rotating in parallel with the camshaft, a follower as a follower that contacts the peripheral edge of the cam plate and reciprocates in the axial direction is provided. The axial reciprocation is transmitted to the armature to move the armature outward in the axial direction, thereby releasing the armature from contact with the friction plate and releasing the braking or engagement as a clutch.
More specifically, a camshaft is rotatably implanted above the radially outer peripheral surface of the yoke of the electromagnetic brake / clutch, and a plate cam eccentric to the camshaft and fitted vertically outside is used as a motor joint. 1) A plate-like driven portion which is moved in parallel with the rotation axis in contact with the peripheral edge of the driving node is provided at a portion away from the edge of the yoke, parallel to the end surface of the yoke, or the tip portion is attached to the end surface of the yoke. An extended portion that is bent inward in the radial direction so as to approach, and this extended portion is connected to the armature at a predetermined position with a connecting pin, etc., and the movement of the follower in the axially outward direction is transmitted to the armature. The armature is released from contact with the friction plate by the lever mechanism that moves outward in the axial direction. 2) As a lever mechanism for this purpose, specifically, this plate-shaped follower is bent at a right angle at the end surface of the yoke and extended to a position slightly below the rotation axis. Is bifurcated so as to hold the hub from the outside, and is formed into a rounded inverted-Y shape of Roman alphabet as a whole, or is extended as it is to make a rectangular plate material. This solves the problem by releasing the braking of a device that has been de-energized due to a power failure or the like and is still being braked, without using a spring or a release member having a complicated shape.

[0010]

FIG. 1A is a front view of a first embodiment of a manual release mechanism according to the present invention, and FIG.
FIG. 2 is a sectional side view taken along the line BB of FIG. In the electromagnetic clutch / brake to which the present invention is applied, since the electromagnetic clutch and the electromagnetic brake are similar in principle, the electromagnetic brake will be described below with reference to FIG. As shown in FIG. 1 (B), an annular yoke 2 having a built-in electromagnetic coil 1 and forming a brake body is mounted on a brake by a stud bolt 5 via a cylindrical spacer 4 located at a circumferentially equal position. Attached to body 6. A ring-shaped plate 7 is concentrically fixed to the brake mounting body 6 with a countersunk screw or the like.
A friction plate 9 is sandwiched between the plate 7 and the armature 8. A square hole 9a shown in FIG. 1A is formed in the center of the friction plate 9, and a square hub 10 is slidably engaged in the square hole 9a in the axial direction. The hub 10 is not shown. It is fixed to the rotation shaft 11 by a key and rotates integrally. 16e indicates a contact point between the cam plate 15c and the driven portion 16a. Hereinafter, the description in item [0010] is irrelevant to the operation of the electromagnetic brake. When the coil 1 is not energized, as shown in FIG. 1 (D), the coil springs 12 arranged at three circumferentially equal positions on the inner peripheral surface of the yoke 2 as a brake body are separated from the armature 8, Since the friction plate 9 is pressed against the plate 7 and stopped, the rotation of the rotating shaft 11 is braked. In this case, the space between the armature 8 and the yoke 2 is pressed by the spring 12 so that FIG.
Clearance c ₁ occurs, is braked, as shown in. When the coil 1 is energized via the lead wire 3, the armature 8
Is sucked by the yoke 2 as a brake main body, so that there is almost no friction between the yoke 2 and the side surface of the friction plate 9, and the braking of the rotating shaft 11 is released.

As shown in FIGS. 1 (A) to 1 (E), a cam shaft 15a is axially rotatably implanted at the outer periphery of the brake body, at the position shown at the top in the figure. This camshaft 15
A handle 15b, such as a rod-shaped or annular ring, for rotating the cam shaft 15a is attached to the outer peripheral portion near the distal end of “a” directly or manually via a wire. As shown in FIG. 1C, a cam plate 15c having a diameter of R + r is fitted around the camshaft axis O around the outer periphery of the camshaft 15a, and the camplate is concentric with the rotary shaft 11. When the cam plate 15c is used as a main joint, and a driven portion 16a that can move in the axial direction while being in contact with the surface of the cam plate is arranged, the driven portion 1
6a becomes a so-called follower, and can reciprocate in the axial direction up to a stroke twice as large as the eccentric radius r of the surface of the cam plate 15c. The diameter of the cam plate 15c is made larger by r than the diameter R of the rotation axis O. However, when used, it is not necessary to rotate the cam plate 15c from the minimum diameter portion to the maximum diameter portion. A position up to a maximum of c ₂ = c ₁ corresponding to the axial movement distance c ₂ required to separate 8 from the friction plate 9 may be set as the operating point.

[0012] The follower 16a is a connecting portion 16b as an extension part bent at a right angle at a position a predetermined distance away c ₂ from the tip in contact with the cam plate 15c, is usually 1
As shown in (A), the rotary shaft 11 is branched into bifurcated leg-like connecting portions 16b that resemble a rounded Roman inverted-Y shape holding the rotating shaft 11 from both outer sides. Two connection pins 17 extending in parallel to the rotation axis from a position equidistant from the axis of the rotation axis near the ends of both connection portions 16b branched into two branches,
The positions corresponding to each of the armatures 8 are connected.
FIG. 1 shows the connection between the armature 8 and the connection pin 17.
As shown in (B) and (D), a countersunk hole 8a or a stepped hole (not shown) is formed in the armature 8, and the tip of the connecting pin is set as a countersunk head 17a or inserted into the stepped hole. As a flat head pin held by the stepped portion, the tip of the connecting pin is prevented from projecting beyond the inner end face 8c of the armature 8 in any case. FIG. 1 (B) shows the format of connecting portion 16b is translated by c ₂ with the movement of the follower 16a, thereby manually released at the time of power failure is enabled. Figure 1 (E) is not necessary connecting portion 16b is not necessarily a right angle bend to the rotation axis, is an indication that it is sufficient translation only c ₂ with the movement of the follower 16a.

FIG. 2A shows a second embodiment of the present invention in which the driven connecting plate 16 'is provided on the outer corner of the yoke 2 with the driven portion 16'a in contact with the small diameter portion of the cam. It is bent along to form a connecting portion 16'b. FIG.
As shown in (B), instead of moving the connecting portion 16'b in parallel, the contact point 16'g of the driven portion 16'a remains in contact with the radial end 16'g of the driven portion 16'a against the outer end surface 2a of the yoke.
And the armature 8 moves outward in the axial direction of the connection pin 17 by leverage (leverage), with the mounting position of the connection pin 17 in the middle of the connection portion 16 ′ b serving as a point of action. The braking or clutch connection is released.
In FIGS. 2A and 2B, instead of the normal camshaft shown in FIG. 1, a smooth portion 15'a below the neck of a commercially available hexagonal head bolt is used as shown in FIG. 2C. This is a manual release cam 15 'which is machined and has a small diameter portion 15'b perpendicular to the rotation axis, which satisfies c ₂ <c _1, and is a very effective structure in terms of cost reduction.

FIG. 3 is a front view showing a third embodiment of the present invention, in which the driven connecting plate 1 of the first and second embodiments is shown.
Instead of 6 or 16 ', the driven connecting plate 16 "of the present invention has an elongated L-shaped front section, and the connecting portion 16" b is formed as a rectangular member. This driven connecting plate 16 ″
As in the first embodiment, the leg is bent in parallel along the end surface of the yoke at a position at a predetermined distance from the tip that comes into contact with the cam plate to form one leg-like connecting portion 16 ″ b. The radially outer end extends beyond the radially outer end of the rotary shaft outwardly to a tip 16 "g, and a hole through the connecting pin near the end of the leg and at a position not interfering with the rotary shaft. 1
Open 6 "f. Rectangular connecting portion 16" b shown in FIG.
Cannot be used as leverage form.

In the first embodiment, the driven connecting plate 16 is shown as an inverted Y-shaped two-legged lever, but the lower portion is supported by two horizontal fixed points passing through the center of the rotating shaft. If the upper end is moved by the small diameter portion 15'b of the manual release cam 15 'and acts as a parallel movement or a lever, it may be an inverted T-shape, a triangle, a magnifying glass shape or a UFO shape. In the case of the UFO type or the UFO type, the number of the two through holes 2f may be one. Alternatively, the lower portion is fixed to the center of the rotating shaft or a point slightly below the center, and the upper end is the small diameter portion 15 'of the manual release cam 15'.
Moved by b, translation or lever (lever)
A long rectangular plate-like lever as in the third embodiment may be used as long as it functions as a lever. Further, the countersunk head 17a is engaged with the countersunk hole 8a of the armature 8 and the screw portion 17b is freely movably engaged with the through-hole 16f of the driven connecting plate 16 through the countersunk bolt type connecting pin 17. However, it is not always necessary to make a countersunk hole, and the tip of the connecting pin 17 can be stopped by a caulking, a snap ring, a pin strike, or the like, instead of being screwed to the nut 18. As shown in FIG. 1B, in a non-excited state in which the coil 1 is not energized, the armature 8 is pushed leftward in the figure by a plurality of coil springs 12 and a lock nut 18 is provided.
Is fixed with a bond or the like to such an extent that the countersunk head 17a of the connecting pin 17 does not protrude outside the countersunk hole 8a. Electromagnetic coil 1
When power is not supplied to the brake, as described above, the brake is braked in the state of FIG. 1D, but if it is necessary to release the brake that has been stopped in the event of a power failure or the like,
When the manual release cam 15 is rotated manually or by a remote control using a wire or the like, for example, to the right by about 110 °, the connecting portion 16b bent as an extension of the driven portion 16a becomes
As shown in FIG. 1B, the armature 8 is displaced from the end face of the yoke 2 to be in the state shown in FIG. 1B. The armature 8 is pulled toward the yoke 2 of the brake body by the connecting pin 17 against the spring force of the compression coil spring 12. is, the gap c ₁ is the braking of the brake can rotate is released occurs between the outer surface of the friction plate 9.

[0016]

According to the present invention, a low-cost material or a commercially available product is used, and an operating rod and a releasing member having a complicated structure and a coil spring for operating these components are not required. Thus, a manual release mechanism is obtained which is much lower in cost than the above, and is functionally selected as a working point in a range from the small diameter portion to the large diameter portion of the cam plate.

[Brief description of the drawings]

FIG. 1A is a front view of a manual release mechanism according to a first embodiment of the present invention, and FIG. 1B is a view of FIG.
FIG. 3C is a schematic plan view of a cam plate used in the present invention, and FIG. 3D shows the operation of a parallel displacement type connecting plate according to the first embodiment of the present invention. Sectional side view,
FIG. 7E is a cross-sectional side view showing another type of connecting plate according to the first embodiment of the present invention.

FIG. 2A is a side sectional view of a manual release mechanism according to a second embodiment of the present invention, and FIG. 2B is a partial sectional side view showing a state of a connecting plate in a manually released state. FIG. 9C is a perspective view of a camshaft using a commercially available bolt according to the second embodiment of the present invention.

FIG. 3 is a front view showing an arrangement of a connecting plate according to a third embodiment of the present invention.

FIG. 4 is a side sectional view of a negative-acting electromagnetic brake according to Prior Art 1.

FIG. 5 is a plan view of the negative-acting electromagnetic brake shown in FIG. 4;

FIG. 6 is a side view showing the operation of the negative actuation type electromagnetic brake of FIG. 4;

7A and 7B are diagrams showing the prior art 2, in which FIG. 7A is a front sectional view of the brake release device of the negative-acting electromagnetic brake, and FIG. 7B is a partial front view of the above.

[Explanation of symbols]

1: electromagnetic coil 2: yoke 2a: outer end surface 2f: through hole 16f, 16'f, 16 "f, 8a: through hole 3: lead wire 4: cylindrical spacer 5: stud bolt 6: brake mounting body 7: Plate 8: Armature 8a: Countersink hole 8c: Inner end surface 9: Friction plate 9a: Square hole 10: Hub 11: Rotating shaft 12: Coil spring 15, 15 ': Manual release cam 15'a: Smooth portion 15a: Cam shaft 15b: Handle 15'b: Notch (small diameter portion) 15c: Cam plate 15'c: Head (handle) 15'd, 17b: Screw 16, 16, 16 ', 16 ": Follower connection plate 16a, 16'a : Followed portions 16b, 16'b, 16 "b: Connecting portions 16e, 16'e: Contact points 16'g, 16" g: Tip 17: Connecting pin 17a: Head of connecting pin 18, 18e: Lock nut c _1, c _2, c ₃ : Gap

Claims (4)

[Claims] 1. A rotating shaft (11), and the rotating shaft (11)
A yoke (2), which incorporates an electromagnetic coil (1) and functions as a brake body, and a hub (10) externally fitted to the hub (10), a plate (7) fixed to a brake mounting body (6), An armature (8), which is mounted with a predetermined gap therebetween through a coil spring (12) and is movable in the axial direction, is disposed between the armature (8) and the plate (7). A non-excited electromagnetic brake having a friction plate (9), and in a non-excited state, the plate (7), the armature (8) and the friction plate (9) are brought into frictional contact to prevent rotation of a rotating shaft; As a manual release mechanism of the clutch, a camshaft (15) having a handle (15b) rotatably implanted on the outer peripheral surface of the yoke (2) in parallel with the rotation axis.
a), a manual release cam (15) having a cam plate (15c) fitted around the cam shaft (15a) and rotating integrally with the cam shaft (15a); A driven portion (16a) that is driven in contact with the peripheral edge, and a connecting portion (16b) that moves as the driven portion (16a) moves outside the end wall of the yoke (2) as an extension of the driven portion. ) Having a driven connecting plate (1)
6), the driven connecting plate (16) is connected to the armature (8) at a predetermined position, and the armature (8) is connected to the friction plate (15) against the axial movement of the cam plate (15c). 9) a manual release mechanism for the non-energized electromagnetic brake / clutch comprising: 2. The driven connecting plate (16) is fixed to the driven portion (16a) at a predetermined stage when the driven portion (16a) shifts from a small diameter portion to a large diameter portion of the cam plate (15c). Following this, the connecting portion (16b) moves in parallel, and the armature (8) is connected to the friction plate (9) via the connecting pin (17). 2. The method according to claim 1, wherein the contact is separated from the contact.
A manual release mechanism for the non-excitation actuated electromagnetic brake / clutch as described. 3. The manual release cam (15) is formed as a cam shaft using a commercially available bolt, and has a smooth portion (15 ') below its neck.
a) is formed with a notch surface (15'b) perpendicular to the rotation axis to form a small-diameter portion of the cam, a head (15'c) of which is a handle rotated by a spanner, and a screw portion (15) of the bolt. 3. The manual release mechanism of a non-excited operation electromagnetic brake / clutch according to claim 2, wherein 'd) is screwed into a screw hole provided on an outer peripheral surface of the yoke. 4. The driven connecting plate (16 ') includes a driven portion (1).
6'a) is bent at a right angle along the outer end surface of the yoke (2) while the small diameter portion (15'b) of the cam is in contact with the cam plate, and the driven portion (16'a) is connected to the cam plate. (15c)
In the state of contact with the large diameter portion of the yoke (2 '), the distal end of the connecting portion (16'b) is moved outward in the axial direction.
The movement is restrained closely to the outer end face of the connecting pin (1).
7) is the position of the driven part (1
4. A non-excited electromagnetic brake according to claim 3, wherein the armature is moved outwardly in the axial direction following 6'a) to separate the armature from contact with the friction plate. Manual release mechanism of clutch.