JP2007161436A - Elevator and emergency stopper used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely stop a car in an emergency, by preventing damage of a sliding surface of a ceramic friction material held by a damper of an emergency stopper for an elevator. <P>SOLUTION: This emergency stopper for the elevator can sandwich a guide rail arranged on a hoistway wall of the elevator. The damper 10 is arranged under the car. When the car becomes a predetermined speed or more, a pressing means presses the damper to the guide rail. A plurality of bottomed or non-bottomed recessed parts are formed in the damper, and the ceramic friction material 12 is fitted in these recessed parts. The friction material is formed so that an end surface lower part on the side opposed to the guide rail is formed as a plate 14 in a state of being installed in the damper, and an upper part is formed as an inclined face 13 or a curved surface such as separating from the guide rail. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an elevator, and more particularly to an elevator emergency stop device that operates when the speed of the elevator exceeds a predetermined speed.

  Patent Document 1 discloses an example of an emergency stop device that is a safety device that stops a car at an appropriate deceleration when the car falls due to cutting of a rope that drives an elevator or the like. In order to obtain stable braking characteristics even under heat resistance exceeding 1000 ° C. and high speed and high response, the emergency stop device described in this publication is designed to protrude from the brake body and the braking surface side of this body. The embedded protrusion has a columnar or polygonal columnar brake piece with rounded corners. The brake piece has other ceramic particles dispersed in the ceramic base material.

  Another example of an emergency stop device using a ceramic brake piece is described in Patent Document 2. In the emergency stop device described in this publication, a ceramic brake piece is embedded on the braking surface side of the brake body so as to protrude from the braking surface in order to prevent the brake piece from hitting the piece, and the embedded portion is soft. While arranging the metal, a gap allowing deformation of the soft metal is formed.

Japanese Patent Laid-Open No. 10-182031 JP 2000-191252 A

  In the emergency stop device for an elevator provided with the ceramic brake pieces described in Patent Document 1, a plurality of ceramic brake pieces are arranged on the braking surface side, so that the sliding surfaces of the brake pieces are flat. Therefore, it is necessary to prevent the contact with one piece, which increases the number of assembly steps. In addition, if a collision occurs, only a part of the brake pieces contributes to braking, and the braking performance is deteriorated.

  In the emergency stop device described in Patent Document 2, ceramic pieces are embedded in a base metal through a soft metal member, and a plurality of ceramic pieces are uniformly applied to the rail, so that contact with each other is prevented. However, when the emergency stop is operated, a shearing force of 1 kN or more is applied to the ceramic piece, and the deflection occurs. As a result, the contact between the rail and the ceramic piece may come into contact with the piece. When the piece hits, a portion that does not slide and a portion that does not slide are generated on the sliding surface of the same ceramic piece, and uneven heat distribution due to sliding heat occurs on the sliding surface. As will be described later, the present inventors have clarified for the first time by experimental research that the non-uniform heat distribution on the sliding surface of the ceramic piece resulting from this piece contact causes the ceramic piece to break.

  The present invention has been made under such knowledge, and an object of the present invention is to prevent ceramic sliding surface damage due to thermal stress in an elevator emergency stop device brake having a ceramic piece. Furthermore, the purpose of the elevator emergency stop device is to stop the car surely in an emergency by preventing breakage of the ceramic piece.

  In order to achieve the above object, in an elevator emergency stop device for stopping an elevator car when an abnormality occurs, a brake that can hold a plurality of ceramic friction materials and can hold a guide rail, and this brake The friction material has a shape in which a portion where tensile stress is generated due to heat generated when sliding with the guide rail is cut out, or a plurality of friction materials are arranged in the sliding direction with the guide rail. At least two guide rails are arranged, and the guide rail facing surface side is formed so that the car is stopped by a cutting action when sliding with the guide rail.

  And in the emergency stop device formed in this way, the plurality of ceramic friction materials are formed in a substantially cylindrical shape, and are formed in a shape that is notched on the upper side in the vertical direction on the surface facing the guide rail. It is good to do. The pressing means is arranged on the back side opposite to the guide rail facing surface of the brake element, a guide plate that presses the brake element against the guide rail, a holding means that holds the guide plate on the car, and one end that is braked. It is preferable to include a wire connected to the child and moving the brake in the vertical direction. Further, the friction material may be at least one of silicon nitride, silicon carbide, alumina, and sialon, and the pressing means may have means for pressing the back side of the friction material.

  In order to achieve the above-mentioned purpose, a guide rail installed on the elevator hoistway wall can be sandwiched and a brake element disposed below the car and when the car exceeds a predetermined speed, In an emergency stop device for an elevator equipped with pressing means for pressing the brake element against the guide rail, the brake element has a plurality of bottomed or bottomless recesses, and a ceramic friction material is fitted in the recesses. With this friction material attached to the brake, the lower end of the end facing the guide rail is a flat plate and the upper is an inclined surface or curved surface away from the guide rail, or the friction material is used as a brake. The end face on the side facing the installed guide rail is chamfered at the top edge of the truncated circle, and the wedge shape with only the bottom side in contact with the guide rail. Only were at least one of chamfered shape.

  The friction material has an inclined surface on the back side, and a support member having substantially the same inclination may be brought into contact with the inclined surface, and a fixing means for fixing the friction material to the brake may be provided. . The inclined surface or curved surface of the friction material is preferably from the upper end to a position that is at least one-sixth the vertical length of the friction material, even if the friction material protrudes from the surface of the brake element by 1 to 3 mm. Good.

  Further, in an elevator, it is desirable to attach any one of the above emergency stop devices to the lower part of the car.

  According to the present invention, since the generation of tensile stress due to the thermal load is reduced on the sliding surface of the ceramic piece included in the elevator emergency stop device, the breakage of the ceramic piece is prevented. As a result, the emergency stop device operates effectively, and the car can be surely stopped in an emergency.

  Hereinafter, an embodiment of an elevator according to the present invention and an emergency stop device used therefor will be described with reference to the drawings. FIG. 1 is a perspective view of a car 1 provided in an elevator and an emergency stop device attached to the lower part of the car. A car 1 on which passengers are placed is connected by a rope 3 to a drive system (not shown) on the top floor of the building. In FIG. 1, the details of the door opening / closing machine and the outer frame are omitted for simplification. On both sides of the hoistway 60, a pair of guide rails 2, 2 that guide the car 1 when the car 1 is raised and lowered are installed.

  A pair of emergency stop devices 4, 4 are installed at the bottom of the car 1 so as to sandwich the T-shaped vertical bar portions of the guide rails 2, 2 formed in a T-shaped cross section. The pair of emergency stop devices 4 and 4 are connected by a connection mechanism (not shown). Details of the emergency stop device 4 will be described with reference to FIGS. FIG. 2 is a longitudinal sectional view of the safety device 4, and FIG. 3 is a perspective view of the safety device 4.

  The emergency stop device 4 is configured to be symmetrical with respect to the guide rail 2. The emergency stop device 4 has a pair of brake elements 10 and 10 formed in a trapezoidal cross section. The brake element 10 has a short side at the upper end side and a long side at the lower end. The pair of brake elements 10 and 10 are arranged substantially parallel to the guide rail 3 with a slight gap with the guide rail 2 so that the guide rail 3 can be held. The rear surface of the brake element 10 is a smooth inclined surface with an upper constriction.

  A guide plate 5 that slides on the braking element 10 is disposed on the inclined surface of the braking element 10. The guide plate 5 is held by a guide member. A convex portion (not shown) of the guide plate 5 is fitted in the concave portion 10a of the brake piece 10, and guides the brake piece 10 to a predetermined position while restricting the movement of the brake piece 10 in the left-right direction. The inner side of the guide member 6 is the same inclined surface as that of the brake 10 and the outer side is a vertical surface. The outer peripheral portion of the guide member 6 is surrounded by an elastic body 8 formed in a U shape with the side facing the guide rail 2 opened.

The brake element 10, the guide plate 5, the guide member 6, and the elastic body 8 are accommodated in the housing 9. The housing 9 includes an upper plate 9b for attaching the emergency stop device 4 to the bottom plate of the car 11, a side plate 9a fixed to the outer periphery of the lower surface of the upper plate 9b, and a receiving plate 9c fixed to the lower end of the side plate 9a. The support plate 9c supports the receiving plate 9c from below and the base plate 9e to which the lower end of the support plate 9d is fixed. A notch is formed in the intermediate portion of the upper plate 9b through which the guide rail 2 passes and the intermediate portion of the base plate 9e through which the guide rail passes.

  In order to press the U-shaped elastic body 8 against the guide member 6 at a plurality of locations on the side plate 9a, screws 42 are attached via springs. One end of the brake element 10 is connected to a pull-up bar 50 included in a driving means (not shown) that activates the safety device 4. The guide member 6 is fixed to the housing 9.

FIG. 3 shows a state where the safety device 4 is operated. A plurality of guide rollers 11 are pressed against the inclined surface of the brake element 10. The roller 11 is rotatably held by the guide member 6 and acts so that the brake element 50 can smoothly move upward. As described above, the guide member 6 has an inclined surface parallel to the inclined surface of the brake element 10, and the back side of the guide member 6 is a vertical surface. Get caught. As a result, the lifting rod 50 is pulled up and the safety device 4 operates. When the emergency stop device 4 is operated, the brake element 10 having the concave portion 10 a is restricted in movement in the left-right direction by the convex portion of the guide plate 5, is pulled up with respect to the guide member 6, and spreads the guide member 6. The reaction force that the guide member 6 is spread acts on the brake element 10, and the brake elements 10 move so that the distance between them is reduced. And the guide rail 2 is clamped.

  Details of the brake 10 used for the elevator shown in the above embodiment will be described with reference to FIGS. FIG. 4 is a perspective view of the right brake element 10 shown in FIG. The brake element 10 has four friction members 12 in the vertical direction of the car 1 and two friction members 12 in the width direction of the brake element 10. The quadrangular columnar support 10a that constitutes the brake element 10 is made of cast iron, and a cylindrical hole into which the friction material 12 is fitted is formed.

  Friction material 12 formed in a cylindrical shape shown in a perspective view in FIG. 5 is fitted into the hole of support 10a by shrink fitting, for example. The friction material 12 is made of ceramics (hereinafter referred to as ceramic pins) such as silicon nitride, silicon carbide, alumina, or sialon, and an end portion facing the guide rail 2 protrudes from the support 10a. This protrusion amount is 1 to 3 mm in this embodiment.

  The sliding end face 14 that slides on the guide rail 2 of the ceramic pin 12 is a plane parallel to the guide rail 2 in a state of being attached to the support 10a. However, the part which becomes an upper part in the state attached to the support body 10a (the part which becomes the upper side of the sliding direction during the operation of the safety device 4) is formed in a cutout shape. Further, the circumferential edge (edge) has a curvature of 1 mm or less or is chamfered. If the edge portion is formed in this way, the ceramic pin 12 can exert a cutting action on the guide rail 2 when the safety device 4 is operated.

  The operation of the safety device 4 configured as described above will be described below. When the descending speed of the car 1 reaches the abnormal detection speed set exceeding the rated speed, the speed sensing device installed on the top floor is activated. The speed sensing device grips a governor rope (not shown) connected to the safety device 4. The governor rope is connected to the brake element 10 and raises the brake element 10 relative to the emergency stop device 4 attached to the car 1. The brake element 10 holds the guide rails 2 installed on the hoistway walls on both sides of the car 1, and also spreads and elastically deforms the U-shaped elastic body 8 arranged so as to surround the brake element 10, A frictional force is generated between the guide rail 2 and the brake 10. As a result, the car 1 stops.

  FIG. 6 schematically shows how the brake element 10 descends along the guide rail 2. The ceramic pin 12 moves in the direction of the arrow 10x while being in contact with the guide rail 2. At this time, the edge 12 a of each ceramic pin 12 moves so as to cut the sliding surface of the guide rail 2. As a result, cutting resistance is generated in the guide rail 2, and this cutting resistance acts as a frictional force. The temperature of the guide rail 2 and the ceramic pin 12 rises due to the frictional force, and the guide rail 2, which is a soft material, melts and adheres on the sliding surface. This adhesion increases the frictional force and provides a braking force.

  In order to generate cutting resistance in the guide rail 2 in this way, it is better to sharpen the edge of the ceramic pin 12. However, if a sharp corner is formed in the ceramic pin 12, the ceramic pin 12 is likely to be cracked or chipped due to stress concentration when the ceramic pin 12 comes into contact with the guide rail 2, so that chamfering treatment is performed to alleviate the stress concentration. Apply. Since the ceramic pin 12 is used as the friction material, the friction material 12 is prevented from being softened or seized due to the sliding heat during sliding even if the loading amount of the car 1 is increased. As a result, a predetermined braking force is obtained.

  FIG. 7 schematically shows the stress state on the end face of the sliding portion of the ceramic pin 12 when the safety device 4 is activated. As shown in FIG. 6, when the ceramic pin 12 contacts the guide rail 2, a frictional force acts only on the tip of the ceramic pin 12 and the ceramic pin 12 bends upward. As a result, a portion 17 that slides in contact with the guide rail 2 and a portion 16 that does not contact are formed on the end surface of the ceramic pin 12.

  A case where the ceramic pin 12 has a cylindrical shape will be described. FIG. 7A shows a state when the ceramic pin 12 slides on the guide rail 2 and becomes high temperature, and FIG. 7B shows the moving speed of the ceramic pin 12 as the speed of the car 1 decreases. Is lowered and cooled to a low temperature. The high temperature state is when the emergency stop device 4 operates and the brake element 10 starts to clamp the guide rail, and the speed of the car 1 is high.

A sliding portion 17 and a non-sliding portion 16 are formed on the end surface of the ceramic pin 12. Since the sliding portion 17 has a high temperature of 1000 ° C. or higher, the ceramic pin 12 expands outward at the sliding portion, as indicated by a broken line 18 in the drawing. On the other hand, when the speed of the car 1 becomes low, the expanded ceramic pin 12 contracts inward as indicated by a broken line 19 in FIG.

When the ceramic pin 12 is thus deformed, a tensile force in the sliding surface inward direction is generated at the boundary 7 between the sliding portion 17 and the non-sliding portion 16 of the ceramic pin 12. When the tensile force exceeds the material strength of the ceramic material that is the material of the ceramic pin 12, the ceramic pin 12 breaks at the boundary 7. That is, as the gradient of the heat distribution between the sliding portion 17 and the non-sliding portion 16 increases, the ceramic pin 12 is more likely to break. This thermal gradient tends to be larger for a high speed and large capacity elevator that requires a large braking force or spring pressing force. In that case, the ceramic pin 12 is easily damaged by thermal stress.

  In order to suppress the occurrence of the thermal gradient of the ceramic pin 12 that becomes particularly noticeable in such a high-speed and large-capacity elevator, unsteady heat is applied to the sliding portion 17 and the non-sliding portion 16 generated on the tip surface of the ceramic pin 12. Analyzed. From this unsteady thermal analysis, the temperature distribution at the tip of the ceramic pin 12 was obtained, and the thermal stress was analyzed based on this temperature distribution.

  FIG. 8 shows the time change of the in-sliding stress in the vicinity of the boundary between the sliding portion 17 and the non-sliding portion 16 at the tip of the ceramic pin 12. When the ceramic pin 12 starts to slide on the guide rail 2, compressive stress accompanying the expansion of the ceramic acts on the boundary portion 7 of the ceramic pin 12. As the sliding progresses, the tensile stress accompanying the ceramic shrinkage acts on the boundary portion 7.

  In general, the material strength of ceramics is lower in tensile strength than in compressive strength. Also, ceramic breakage occurs when the tensile strength is exceeded. Therefore, as in the ceramic pin 12 shown in FIG. 5, the pin 12 is bent and the portion that does not slide with the guide rail 2 is cut in advance to prevent damage due to thermal stress in the sliding surface.

  FIG. 9 shows the notch shape specifications of the ceramic pin 12. The diameter of the notch pin is D, the notch length is L, and the notch angle is ψ. Ceramic pins 16 having a diameter D of D = 8 to 16 mm were manufactured, and a sliding experiment was conducted in a pin-on-disk test. SS400 material which is the material of the guide rail 2 was used for the disk. The ceramic pin 12 is pressed against the disk surface with a predetermined pressing load. At the same time, the friction coefficient was measured by measuring the frictional force until the disk rotation was decelerated and stopped. Furthermore, the presence or absence of damage to the sliding surface of the ceramic pin 12 was confirmed visually.

  As a result of a sliding test at a surface pressure of 20 MPa to 100 MPa and a sliding start speed of 15 m / sec, no damage was observed in the ceramic pin 12 at 40 MPa or less. When the surface pressure was increased to 40 MPa or higher, the failure probability gradually increased, and at 100 MPa, the ceramic pin 12 was damaged in almost all the tests. And the damaged part position of the damaged pin 12 was located in the range of 1/5-2/3 of the pin diameter D from the upper end of a sliding face.

  From the results of this pin-on-disk experiment, it was known that the notch length L of the ceramic pin 12 should be at least 1/5 of the pin diameter D from the upper end of the sliding surface. Further, in order to generate a predetermined frictional force by the ceramic pins 12, it is necessary to leave as much as possible an edge for cutting the guide rail 2. Therefore, the maximum notch position is made half or less of the pin diameter D. According to the above-described experiment, there is no large difference in the coefficient of friction between the ceramic pin not formed with the notch portion and the ceramic pin formed with a shape notched to half the pin diameter D, and the necessary friction force can be secured. It was.

  In the pin-on-disk experiment, the notch angle ψ was also changed. The notch angle ψ was changed in the range of ψ = 15 ° to 45 °. In this range, the ceramic pin 12 was not damaged. The reason for this is that the part that does not slide is removed from the end face of the ceramic pin, or even if there is a part that does not slide, the stress and strain accumulated by the non-uniform temperature distribution easily escapes out of the plane. Because it is. From this experimental result, it is known that if the notch angle ψ is up to 45 °, the accumulated stress strain easily escapes out of the plane.

  The braking load in an actual elevator will be described below. This is the case where the car 1 having a loading capacity of 5 tons is lifted up and down. The total falling mass including the car 1, the suspension rope 3 and the incidental equipment is about 26 tons. If the drop start speed when the elevator is abnormal is 800 m / min, the friction coefficient between the brake 10 and the guide rail 2 is set to 0.25 to 0.5 in order to stop within 20 m after the fall. The pressing force of 10 needs to be 400 kN or more at maximum. Here, the coefficient of friction between the brake element 10 and the guide rail 2 is a standard value when the guide rail 2 is a steel material and the friction material 12 of the brake element 10 is a ceramic material.

  The surface pressure when holding a plurality of ceramic pins 12 on the brake element 10 having a sliding surface with a length of 200 mm in the up-and-down direction and a length of 40 mm in the width direction is at least 50 Mpa. Therefore, when the emergency stop device 4 having the ceramic pins 12 is mounted on the elevator, it is necessary to consider the damage caused by the thermal stress on the sliding surface of the ceramic pins 12.

  FIG. 10 shows various modifications of the ceramic pin 12. These ceramic pins have a shape that prevents breakage due to the above-described thermal stress. FIG. 2A shows a pin 21 having a truncated circular cross section. Since the sliding surface is substantially half-moon shaped, there are almost no non-sliding parts. At the edge of the meniscus, the guide rail 2 is cut, and the sliding surface adheres and wears to generate a braking force. If the hole shape of the support 10a of the brake element 10 is also matched with the shape of the pin 21, the direction of the ceramic pins can be made uniform, and rotation around the axis can be prevented.

  FIG. 2B shows an edge-deviation chamfered pin 22 in which the peripheral edge of the pin 22 formed in a cylindrical shape is chamfered with an eccentric circle. A curvature of at least 1 mm or more is provided in the edge portion 22a on the sliding surface side so that strain due to thermal stress is easily released out of the plane. However, if a curvature is provided on the entire edge, the cutting resistance of the guide rail 2 by the edge is reduced and the braking force is reduced. Therefore, a curvature is provided only in the non-sliding portion that is on the upper side in the sliding direction during operation of the safety device 4.

  FIG. 10C shows a wedge-shaped pin 20 having a shape obtained by cutting a cylinder along an oblique plane. The tip portion 20a has an oblique oval shape. The sliding part is only the tip, the temperature gradient due to sliding heat is small, and it is difficult to break. Although the guide rail 2 is cut by the tip portion 20a to obtain a braking force, the friction coefficient is lowered because the action of causing the guide rail to adhere and wear is small. FIG. 10D shows a tip curvature shape pin 23 with a rounded tip. Since the tip is formed to have a large curvature 23a, strain is easily released out of the plane. However, since the force which cuts the guide rail 2 hardly acts, a friction coefficient falls. In the wedge-shaped pin 20 and the tip curvature-shaped pin 23, the friction coefficient tends to decrease, so that the pressing force is increased to ensure the braking force.

  Another embodiment of the ceramic pin is shown in a perspective view in FIG. In the present embodiment, the ceramic pin is not a cylindrical shape but a polygonal polygon pin 15. The end surface that slides on the guide rail 2 has a substantially vertical surface 15c and an inclined surface 15a formed above the vertical surface 15c. Instead of the inclined surface 15a, a shape having a certain degree of curvature may be used. It is desirable to chamfer 15a on the side corners.

  In the said Example, in order to improve the cutting effect of the ceramic pin 12, the ceramic pin 12 protrudes slightly from the support body 10a. This protrusion amount is set to 1 to 3 mm for the following reason. Although the amount of protrusion of the friction material 12 depends on the size of the friction material 12, it is set so as not to break at the fitting portion with the support 10a due to the frictional force acting on the friction material 12. If the protruding amount of the friction material 12 is too short, the cutting powder of the guide rail 2 generated by the frictional force between the brake 10 and the guide rail 2 accumulates between the brake 10 and the guide rail 2.

  When the cutting powder accumulates, the sliding heat between the guide rail 2 and the support 10a is accumulated in the cutting powder, the support 10a is thermally deformed, and the ceramic pin 12 hits the guide rail 2 so that a predetermined friction force is applied. There is a risk that it cannot be secured. Further, when the safety device 4 stops, the sliding heat accumulated under the ceramic pins 12 is rapidly taken away through the lump of cutting powder. As a result, the ceramic pin 12 contracts, tensile stress is generated, and the ceramic pin 12 may be cracked.

  Since the ceramic pin 12 which is a friction material slides on the guide rail 2 at a high speed, the ceramic pin 12 easily rotates around the axis of the ceramic pin 12 when fitted to the support 10a. Therefore, it is desirable to provide a rotation stopper that prevents this rotation. When the friction material 12 is fitted to the support 10a by shrink fitting, depending on the finished state of the friction material 12 and the support 10a, the support 10a may have little or no tightening allowance for tightening the friction material 12. is there. In this case, when the emergency stop device 4 is operated and non-uniform frictional force is generated in the sliding surface of the ceramic pin 12, the ceramic pin 12 may be rotated around its axis.

In order to avoid such a problem, the ceramic pin 12 is prevented from rotating. FIG. 12 is a cross-sectional view showing a structure for preventing the ceramic pin 12 from rotating. The support 10 a includes an upper plate 24 that is disposed on the side facing the guide rail 2 and a bottom plate 26 that is disposed on the back side of the upper plate 24. The bottom plate 26 is tightened with screws 28 from the top plate 24 side. The screw 28 fastening portion hole formed in the upper plate 24 is sandwiched so that the head of the screw 28 does not protrude.

  Two cylindrical pins 25 and 27 that suppress the rotation of the ceramic pins 29 are fixed to the surface of the bottom plate 26 facing the top plate 24. Concave holes 29a and 29b are formed in the bottom surface of the ceramic pin 29 so as to be fitted to the pins 25 and 27. Since the ceramic pins 29 are positioned by the pins 25 and 27, the ceramic pins 29 are rotated by the non-uniform friction force generated during the operation of the emergency stop device 4 even if there is almost no tightening allowance at the time of shrink fitting. Can be prevented. Although not shown, if the pins 25 and 27 and the recessed holes 29a and 29b are formed in a shape other than a cylinder, for example, a quadrangular prism, the pins 25 and 27 and the recessed holes 29a and 29b need only be provided around the ceramic pin 29. I can stop it.

  Another embodiment for preventing the rotation of the ceramic pin is shown in a sectional view in FIG. This is more effective when the rotational force acting on the ceramic pin is larger than in the case of FIG. In the embodiment shown in FIG. 12, when the frictional force increases, the force applied to the pins 25 and 27 also increases, and the pins 25 and 27 may be damaged.

  Therefore, the base 33 is attached to the side surface of the upper plate 24 of the bottom plate 26. The pedestal 33 is fastened to the bottom plate 26 from the bottom plate 26 side with screws 32. The surface on which the pedestal 33 comes into contact with the ceramic pin is an inclined surface 33 a, and the direction of the inclined surface 33 a is determined by positioning pins 30 and 31 fixed to the bottom plate 26. The bottom surface 29a, which is the end surface opposite to the sliding surface of the ceramic pin 29, is formed with the same inclination as the inclined surface of the pedestal 33, and the ceramic pin 29 abuts the pedestal inclined surface 33a exactly.

  Even if the frictional force acting on the tip surface 29b of the ceramic pin 29 is large, the rotational force is supported by the inclined surface 33a of the pedestal 33, so the ceramic pin 29 does not rotate. Further, since the rotational force supported by the base 33 is supported by the fastening force of the screw 32, the positioning pins 30 and 31 can be prevented from being damaged. Furthermore, if the low friction member is processed on the inclined surface 33a, the rotational force supported by the pedestal 33 can be further reduced, and the pedestal 33 is less likely to be damaged.

FIG. 14 is a perspective view showing still another embodiment of the ceramic pin. The ceramic pin 36 has a truncated circular shape in cross section, and one of the left and right side surfaces is a flat surface 36a while being held by the support 10a. Although not shown, the support 10a is formed with a truncated circular hole into which the ceramic pin 36 is fitted. It is desirable to chamfer the corners 36b and 36c on the cut side surfaces to relieve stress when a rotational force is applied.

  The circumferential direction position of the flat surface 36a avoids the same direction as the direction 37 in which the brake element 10 falls. Since the falling direction is the side where the guide rail 2 is cut when the safety device 4 is operated, the greatest force is applied. If the plane 36a is positioned in this direction, the acute shape of the corner 36d may be damaged.

On the contrary, if the flat surface 36a is positioned above the direction opposite to the falling direction, FIG.
The shape is such that the thermal stress shown in (a) is relieved, and both damage prevention and anti-rotation can be achieved. A plurality of planes may be formed. However, when the number increases, the length of the end face for cutting the guard rail 2 may be shortened, and a predetermined braking force may not be obtained.

  According to each of the above embodiments of the present invention, the plurality of ceramic pin friction members 12 are attached to the sliding side of the brake 10, and the shape of the sliding end surface of the ceramic pin 12 sliding with the guide rail 2 is non-uniform. Since it is formed on the surface, stress relaxation is achieved, and damage to the ceramic pin due to sliding heat can be prevented. Further, in the case of a pin having a stress-relaxed shape, it is easy to align the direction of each pin in the same direction. Further, the rotation of the ceramic pin about the axis can be prevented without a shrinkage allowance for shrink fitting.

1 is a perspective view of an embodiment of an elevator apparatus according to the present invention. It is a front view of the emergency stop apparatus used for the elevator apparatus shown in FIG. FIG. 3 is a partial perspective view of the safety device shown in FIG. 2. It is a perspective view of the brake which the emergency stop apparatus shown in FIG. 2 has. It is a perspective view of the friction material which the brake element shown in FIG. 4 has. It is a figure explaining operation | movement of an emergency stop apparatus. 6A and 6B are diagrams illustrating a sliding state of the friction material illustrated in FIG. 5, in which FIG. 5A illustrates a high temperature state and FIG. 5B illustrates a low temperature state. It is a graph showing an example of the stress change of the sliding surface of a friction material. It is a perspective view of other examples of a friction material. It is a perspective view of the various modifications of a friction material. It is a perspective view of other Example of a friction material. It is a fragmentary sectional view of other examples of a brake child. It is a fragmentary sectional view of other examples of a brake child. It is a perspective view of other Example of a friction material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Car, 2 ... Guide rail, 4 ... Emergency stop device, 5 ... Guide plate, 6 ... Guide member, 8 ... Elastic body, 10 ... Brake, 12, 20-23 ... Friction material (ceramics pin).

Claims (12)

  In an elevator emergency stop device that stops an elevator car when an abnormality occurs, the elevator has a brake that can hold a plurality of ceramic friction materials and can hold the guide rail, and a means for pressing the brake against the guide rail. The elevator emergency stop device according to claim 1, wherein the friction material is formed in a shape in which a portion where tensile stress is generated by heat when sliding with the guide rail is cut out.   In an elevator emergency stop device that stops an elevator car when an abnormality occurs, the elevator has a brake that can hold a plurality of ceramic friction materials and can hold the guide rail, and a means for pressing the brake against the guide rail. The plurality of friction materials are arranged in the sliding direction with respect to the guide rail, and the guide rail facing surface side is formed so as to stop the car by a cutting action when sliding with the guide rail. Elevator emergency stop device.   The plurality of ceramic friction materials are formed in a substantially cylindrical shape, and are formed in a shape that is a surface that faces the guide rail and is cut out in the vertical direction. The emergency stop device for elevators according to 1 or 2.   The pressing means includes a guide plate that is disposed on the back side opposite to the guide rail facing surface of the brake element, presses the brake element against the guide rail, a holding means that holds the guide plate on the car, and one end of the pressing means The elevator emergency stop device according to claim 1 or 2, further comprising a wire connected to the brake element and moving the brake element in a vertical direction.   3. The elevator according to claim 1, wherein the friction material is at least one of silicon nitride, silicon carbide, alumina, and sialon, and the pressing means includes means for pressing the back side of the friction material. Emergency stop device.   A guide rail installed on the elevator hoistway wall can be pinched and placed below the car, and when the car exceeds the specified speed, the brake is pressed against the guide rail. In the emergency stop device for elevators, a plurality of bottomed or bottomless recesses are formed in the brake element, and a ceramic friction material is fitted in the recesses. An elevator emergency stop device, characterized in that the lower end face facing the guide rail is a flat plate and the upper part is an inclined surface or curved surface that is separated from the guide rail in a state where the brake is attached to the brake element.   A guide rail installed on the elevator hoistway wall can be pinched and placed below the car, and when the car exceeds the specified speed, the brake is pressed against the guide rail. In the emergency stop device for elevators, a plurality of bottomed or bottomless recesses are formed in the brake element, and a ceramic friction material is fitted in the recesses. The end face on the side facing the guide rail in the state where it is attached to the brake element is chamfered on the upper edge of the truncated circle and the wedge shape with only the lower side coming into contact with the guide rail, only the upper edge An elevator emergency stop device having a chamfered shape.   8. The emergency stop device for an elevator according to claim 6, wherein the friction material has an inclined surface on the back side, and a support member having substantially the same inclination is brought into contact with the inclined surface. 9.   The elevator emergency stop device according to claim 6 or 7, further comprising fixing means for fixing the friction material to the brake element.   7. The elevator emergency stop device according to claim 6, wherein the inclined surface or curved surface of the friction material is from the upper end to a position at least one-sixth of the vertical length of the friction material.   The emergency stop device for an elevator according to claim 6 or 7, wherein the friction material protrudes 1 to 3 mm from the surface of the brake. An elevator comprising the emergency stop device according to any one of claims 1 to 11 attached to a lower portion of a car.

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