JP2002193565A - Elevator braking system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reduce the size and weight of a highly reliable elevator braking device having both heat resistance and impact resistance. SOLUTION: A holding body 3 provided with a plurality of holes in an opposing surface facing a sliding surface of a damped body 10 and a tip end of the holding body 3 protruding from the opposing surface toward the damped body 10 side. A brake element 1 comprising a plurality of friction pieces 2 made of ceramic material inserted and fixed in respective holes, and a pressing force generating mechanism for pressing the brake element 1 against the braked member 10 during an emergency stop. In the elevator braking device, each sliding surface of the plurality of friction pieces 2 is made to coincide with a surface facing the sliding surface of the braked body 10 in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking device for an elevator for emergency-stopping an elevator car, which is an elevating body, and more particularly to a braking device which is pressed against a brake target (guide rail) during an emergency stop. The present invention relates to a structure of a brake element that generates a braking force.

[0002]

2. Description of the Related Art FIGS. 6 to 8 show "New Edition Machine Design Handbook".
(Issued by Maruzen Co., Ltd. in 1973) is a schematic diagram of a typical braking system using the frictional force of a block brake, a band brake, and a disk brake. In each figure, 2
Numeral 0 denotes a braked body, 21 denotes a braker, and the braking device includes a braked body 20 interlocked with an object that moves relative to a braking device to be braked, and a sliding surface of the braked body 20. A brake element 21 which is installed so as to be opposed and has a fixed friction piece pressed against the brake element 20;
And a pressing force generating mechanism (not shown) for generating a pressing force for pressing the pressing force. For example, in the block brake system of FIG. 6, the braking force F is represented by F = μ × P, where μ is the friction coefficient and P is the pressing force. For this reason, in order to increase the braking force, it is necessary to increase the product of the friction coefficient μ and the pressing force P.

Here, in order to increase the pressing force P, it is necessary to increase the size of the pressing force generating mechanism such as a spring, a hydraulic / pneumatic device, or an electromagnetic force generating device. Similarly, the structure has to be increased in size. For this reason, the braking device is large and heavy. Therefore, in order to obtain a braking device having a high braking force or a small and lightweight braking device, it is necessary to increase the friction coefficient μ. FIG. 9 is a schematic view of an elevator emergency stop device (i.e., an emergency braking device) disclosed in Japanese Patent Application Laid-Open No. 7-41272 as one application example of a conventional elevator braking device. In the figure, 10 is a guide rail which is a braked body installed on a hoistway wall, 11 is an elevator car, 12 is a rope, 13 is an emergency stop device (emergency braking device), and 14 is a pushing force generating mechanism. The spring 15 is a braking body.

A car 11 is suspended from one end of a rope 12 and moves up and down the hoistway along a guide rail 10.
An emergency stop device 13 is attached to a lower portion of the car 11. The emergency stop device 13 sandwiches the guide rail 10 and has a wedge-shaped brake body 15 provided with a brake element for generating a frictional force and an emergency stop. And a pressing spring 14 that sometimes presses the braking element against the guide rail. Normal,
The guide rails 10 are provided in pairs on both sides of the car 11, and two braking bodies 15 are provided for each guide rail so as to sandwich each guide rail 10. , Four in total.

FIG. 10 shows a detailed structure of the brake 15 in the emergency stop device (emergency braking device, hereinafter simply referred to as a braking device) shown in FIG. In the figure, reference numeral 2 denotes a friction piece, and 3 denotes a holder for the friction piece 2. The friction pieces 2 are inserted and fixed in a number of holes formed in the holder 3, respectively. Reference numeral 5 denotes a wedge-shaped member to which a brake element including the friction piece 2 and the holding body 3 is attached, and the friction piece 2, the holding body 3 and the wedge-shaped member 5 constitute a wedge-shaped braking body 15. .

Next, the operation will be described. When the descending speed of the car 11 reaches a speed exceeding a predetermined rated speed due to a failure of the car speed control device, breakage of the rope, or the like,
The brake spring of the brake body 15 is pressed against the guide rail 10 by the pressing spring 14, and the car 11 is decelerated and stopped by the frictional force generated on the sliding surface between the brake rail provided on the brake body 15 and the guide rail 10. . At this time, the brake 15
Therefore, the braking force when four brake elements are provided,
If the friction coefficient is μ and the pressing force of the compression spring is P, then F
= 4 μP. As described above, also in the emergency stop device for an elevator, the braking capacity is determined by the product of the friction coefficient μ and the pressing force P of the brake element, as described in the above-described typical braking device.

In order to increase the pressing force P, it is necessary to make the structure of the safety device 13 including the pressing spring 14 large, and the safety device is large and heavy, and the cost is high. Connect. Therefore, in order to obtain a small and lightweight emergency stop device (braking device), it is necessary to increase the friction coefficient of the brake. Especially, 15m / sec
When the car 11 ascending and descending along the guide rail 10 is braked at a high speed exceeding the above, contact between the friction piece 2 provided on the brake element of the brake body 15 and the braked body (that is, the guide rail 10) due to frictional heat. The surface becomes a high temperature exceeding 1000 ° C., and in the friction piece composed of a steel material such as cast iron generally used as a friction piece, the material is softened, the braking force is reduced due to a decrease in frictional force due to melting and an increase in wear, or There is a risk of braking failure.

FIG. 11 shows the relationship between temperature and hardness (ie, heat resistance) of various materials disclosed in Japanese Patent Application Laid-Open No. 7-41272. As shown in FIG. 11, the cast iron steel rapidly softens from approximately 400 ° C., the alloy steel approximately 600 ° C., and the heat-resistant alloy material approximately 1000 ° C., whereas the ceramic material has a hardness of 1200 ° C. It can be seen that it does not decrease. For these reasons, Japanese Unexamined Patent Publication No.
As disclosed in Japanese Patent Application Laid-Open No. 9-7682 and Japanese Patent Application Laid-Open No. 7-41272, as a method for preventing the friction piece of the brake element from softening and melting, a friction piece made of a ceramic material having excellent heat resistance is used. It is known to be applied to

However, since the ceramic material has low toughness (stickiness), it has a characteristic of being easily cracked by impact. Therefore, when this is used as a friction piece,
For example, at the start of the braking operation, the sliding surface of the friction piece may be damaged due to the collision of the brake element with the brake target, or the impact due to the friction between the operating brake element and the brake target, resulting in a decrease in the braking ability. Or braking may not be possible. In addition, among the ceramic materials, there are relatively high toughness materials such as silicon nitride and zirconia, but when these materials are used as friction pieces, the coefficient of friction with the brake target is low, and in order to obtain a sufficient braking force. However, there is a problem in that the pressing force needs to be increased, and the braking device becomes large and heavy.

FIG. 12 is a view for explaining the detailed structure of the brake in the conventional brake shown in FIG. 10; FIG. 12 (A) is a front view, and FIG. 12 (B) is FIG.
It is a sectional view in the XX line of (A). In the figure,
Reference numeral 1 denotes a brake element, 2 denotes a friction piece, and 3 denotes a holder for the friction piece 2. As described above, the brake element 1 includes the friction piece 2 and the holder 3. Reference numeral 10 denotes a guide rail that is a brake target. In Japanese Patent Application Laid-Open No. 7-41272, in order to improve the above-described problem, as shown in FIG.
A plurality of holes are provided in the surface of the holding member 3 of the brake 1 that is pressed against the guide rail (brake target) 10 at the time of an emergency stop, the surface facing the sliding surface of the guide rail (brake target 10). By inserting and holding the friction piece 2 made of a ceramic material, it is possible to prevent plastic deformation and melting from occurring on the braking surface of the brake 1 during high-speed operation, and the friction piece 2 has a smaller diameter than the hole. Therefore, it is disclosed that since a compressive stress is not normally generated, breakage of the braking surface (sliding surface) of the friction piece 2 due to an impact during operation can be reliably prevented.

[0011]

However, in the brake of the conventional elevator braking apparatus disclosed in Japanese Patent Application Laid-Open No. 7-41272, as shown in FIG. Since the sliding surface of the friction piece 2 is not machined or adjusted so as to coincide with the surface facing the braked body 10, the position of the sliding surface of each friction piece is uneven, and the braking element 1 Is pressed against the sliding surface of the braked member 10, some of the frictional pieces receive an impact, the frictional pieces are easily damaged, and all the frictional pieces slide on the braked body 10. Therefore, the friction area of the entire brake element is reduced, and a large pressing force is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to prevent the sliding surface of a brake element from being melted during a high-speed braking operation, and to prevent an impact during a braking operation. By providing a highly reliable elevator braking device that can reduce damage and reliably perform emergency braking, and by using a braking element that has high braking capability, a pressing force generation mechanism is provided. It is an object of the present invention to realize a small and lightweight elevator braking device.

[0013]

According to the present invention, there is provided an elevator braking apparatus comprising: a holding member having a plurality of holes formed on a surface facing a sliding surface of a member to be braked; A brake element made of a plurality of ceramic material friction pieces inserted and fixed in respective holes of the holding body by projecting the brake element toward the brake object side, and the brake element at the brake object side at the time of emergency stop. In an elevator braking device having a pressing force generating mechanism for pressing, a sliding surface of each of the plurality of friction pieces is made to coincide with a surface facing the sliding surface of the brake target in parallel.

[0014] Further, the plurality of friction pieces of the elevator braking device according to the present invention are characterized in that the peripheral edge of the sliding surface is chamfered or curved.

Further, the plurality of friction pieces of the elevator braking device according to the present invention are characterized in that a plurality of grooves are formed on a sliding surface thereof.

The plurality of friction pieces of the elevator braking device according to the present invention are made of a composite material of a ceramic material and a metal or a metal compound material having a higher friction coefficient than the ceramic material with respect to the braked body. There is a feature.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. The same reference numerals as those in the conventional drawings denote the same or corresponding parts as those in the conventional art. Embodiment 1 FIG. FIG. 1 is a diagram showing a structure of a brake element used in the braking device according to the first embodiment. FIG. 1A is a front view when viewed from a brake target (guide rail) side.
FIG. 2B is a sectional view taken along line XX of FIG. In the drawing, 1 is a brake element, 2 is a plurality of friction pieces, 3 is a holder for the friction piece 2, and 10 is a braked body (guide rail).

The holding member 3 of the friction piece 2 is provided with a number of holes for inserting and fixing the friction piece 2, and the friction piece 2 is inserted into each of the plurality of holes of the holding member 3, The end of each of the friction pieces 2 on the side of the body to be braked (guide rail) 10 protrudes from the opposing surface of the holder 3 on the side of the body to be braked. The material of the friction piece 2 is a ceramic material, the shape of which is cylindrical, and smaller than the diameter of the hole. The brake element 1 composed of the friction piece 2 and the holder 3 is attached to the wedge-shaped member 5 as shown in FIG.
Is composed.

In general, when the friction piece 2 is inserted into and fixed to the holding body 3, when the friction piece 2 and the hole provided in the holding body 3 for inserting the friction piece 2 are machined, and when these are fixed, As shown in FIG. 12, due to the lack of assembly accuracy of the frictional piece, the sliding surface of each friction piece
Since it does not coincide with the surface facing the sliding surface of 0), only a part of the friction piece slides on the braked body, and the friction piece sliding on the braked body is broken by the shock at the time of braking. Easy,
Further, the contact area with the braked body 10 during braking may be reduced. Therefore, in the first embodiment, as shown in FIG. 1, after the brake element 1 has the plurality of friction pieces 2 inserted into the holes of the holder 3 and fixed, the entire sliding surface of each friction piece 2 is covered. Since the surface is machined so as to coincide with the surface facing the sliding surface of the braking body (guide rail) 10 in parallel, it is possible to reduce the damage of the friction piece 2 due to the impact at the time of braking, and to reduce the friction between the brake element 1 and the braking element 1 during braking. The contact area with the brake body 10 can be increased.

A ceramic material having a low toughness and a large sliding surface is easily damaged by an impact. However, by dividing the ceramic material into a number of small friction pieces 2 as in this embodiment,
The individual friction pieces are hardly damaged, and even if some of the friction pieces are damaged or cracked, the other friction pieces do not propagate the damage or cracks. And the risk of inability to brake is greatly reduced. Therefore, the braking element 1 at the start of the braking operation
Impact on the braked body 10 or the frictional impact between the braker 1 and the braked body 10 during operation may damage the sliding surface of the friction piece, reduce the frictional force and disable braking. Can be prevented. As a result, a highly reliable elevator braking device having both heat resistance and impact resistance can be obtained.

When the pressing force is constant, the frictional force tends to increase as the contact surface pressure decreases, so that the brake 1 according to the present embodiment has a high friction coefficient. In the present embodiment, the sliding surface of the brake 1 (that is, the sliding surface of each friction piece 2) is a brake target (guide rail).
Since it matches the surface facing parallel to the sliding surface of 10,
At the time of braking, the contact area between the brake element 1 and the brake target 10 increases, and the contact surface pressure can be suppressed low. Therefore,
Since the pressing force required to obtain the same braking force can be reduced, the pressing force generating mechanism can be reduced, and the braking device can be reduced in size and weight. From the above, it is possible to reduce the size and weight of a highly reliable braking device having both heat resistance and impact resistance.

Embodiment 2 FIG. FIG. 2 is a diagram showing a structure of a brake element used in a braking device according to a second embodiment of the present invention. FIG. 2 (A) is a front view when viewed from a brake target (guide rail) side. FIG. 2B is a sectional view taken along line XX of FIG. In the drawing, 1 is a brake element, 2 is a plurality of friction pieces provided on the brake element 1, 3 is a holder for the friction piece 2, 10
Denotes a brake target (guide rail). As in the case of the first embodiment, the holding body 3 of the friction piece 2 is provided with a large number of holes for inserting and fixing the friction piece 2. The friction pieces are inserted, and the end of each friction piece on the braked body side projects from the opposing surface of the holding body 3 on the braked body side. The material of the friction piece 2 is a ceramic material, the shape of which is cylindrical, and smaller than the diameter of the hole. As in the case of the first embodiment, the brake element 1 including the friction piece 2 and the holder 3 is attached to the wedge-shaped member 5 as shown in FIG. ing.

FIG. 3 is a view for explaining the shape of the friction piece used in the present embodiment. FIG. 3A is a front view when viewed from the brake-receiving body (guide rail) 10 side. FIG.
FIG. 2B is a sectional view taken along line XX of FIG. In FIG. 3, reference numeral 2 denotes a friction piece and reference numeral 2a denotes a chamfered portion formed on the peripheral edge of the sliding surface of the friction piece 2 (that is, the peripheral edge of the end face of the friction piece 2 on the side of the braked member 10). In the elevator braking device according to the present embodiment, as shown in FIG.
It is characterized in that chamfering is performed on the peripheral edge of the sliding surface of the friction piece 2 fixed to the holder 3 of the brake element 1 to provide the chamfered portion 3. By performing the chamfering process on the peripheral portion of the sliding surface of the friction piece 2, an impact due to the collision of the brake 1 with the braked body 10 at the start of the braking operation, and a difference between the braker 1 and the braked body 10 during operation. Can be further mitigated than in the case of the first embodiment, and breakage of brake 1 (that is, brake 1
Can be further reduced.

FIG. 4 is a view for explaining another modification of the friction piece used in the present embodiment.
(A) is a front view when viewed from the braked object (guide rail) 10 side, and FIG. 4 (B) is a cross-sectional view along XX of FIG. 2 (A). In FIG. 3, reference numeral 2 denotes a friction piece, and 2b denotes a curved surface portion formed on a peripheral edge of a sliding surface of the friction piece 2. By forming the peripheral portion of the sliding surface of the friction piece 2 into a curved surface, similarly to the case where the peripheral portion of the sliding surface of the friction piece 2 is chamfered, the braked member 10 of the brake element 1 at the start of the braking operation is formed. It is needless to say that the impact due to the collision with the vehicle and the friction due to the friction between the braking element 1 and the braked body 10 during operation can be further reduced than in the first embodiment.

As described above, the brake element of the elevator braking apparatus according to the present embodiment has a configuration in which the periphery of the sliding surface of the fixed friction piece is chamfered or curved so that each friction piece can be formed. The stress is not concentrated even when a force is applied to the end portion, and the impact force is reduced by the inclined surface of the chamfered portion 2a or the curved surface of the curved surface portion 2b. For this reason, it is possible to reduce the risk of the friction piece 2 breaking due to the collision of the brake element 1 with the braked body 10 at the start of braking and the shock generated by the friction between the braker 1 and the braked body 10 at the time of braking. . Therefore, damage to the brake 1 due to braking can be further reduced, and a highly reliable elevator braking device can be obtained.

Embodiment 3 FIG. FIG. 5 is a diagram for explaining the shape of the friction piece used in the present embodiment.
(A) is a front view when viewed from the braked object (guide rail) 10 side, and FIG. 5 (B) is a XX cross-sectional view of FIG. 5 (A). In FIG. 5, 2 is a friction piece, 2 a is a chamfered portion formed on the peripheral edge of the sliding surface of the friction piece 2, and 2 c is a groove formed on the sliding surface of the friction piece 2. The elevator braking device according to the present embodiment is characterized in that the friction piece 2 of the elevator braking device according to the second embodiment further includes a plurality of grooves 2c formed on a sliding surface thereof.

By forming a plurality of grooves 2c on the sliding surface of the friction piece 2, the frictional force between the brake 1 and the braked body 10 during the braking operation can be further increased. Therefore, in addition to the effect of the elevator braking device according to the second embodiment, the emergency braking can be reliably performed with a smaller pressing force, so that the elevator braking device can be further reduced in size and weight. it can. Needless to say, the same effect can be obtained by forming the peripheral edge of the sliding surface of the friction piece 2 into a curved surface shape as shown in FIG. 4 instead of the chamfered portion 2a.

In each of the above embodiments, the friction piece 2
Although the shape of the sliding surface is circular, the shape of the sliding surface is not particularly limited. For example, a polygon,
A rectangular or elliptical braking element may be used, and the number and arrangement of the friction pieces 2 fixed to the braking element 1 are not particularly limited. In each of the above embodiments, the brake 1
This is realized by fixing all the friction pieces to the friction piece holding body and then polishing the same as a means for matching the sliding surface of (1) with the surface facing the sliding surface of the braked body (guide rail) 10. The method is not particularly limited. Further, the brakes of the braking devices shown in the above-described embodiments are applied to brakes of all the braking devices such as block brakes, band brakes, and disk brakes using frictional force as shown in FIGS. The type of the braking device and the equipment to be mounted are not particularly limited.

Further, in each of the above embodiments, the emergency stop device (braking device) is attached to the car. However, it is also possible to attach the emergency stop device to the counterweight. The present invention is not limited to the above embodiment. Further, in the above-described embodiment, the traction type elevator emergency stop device is shown, but the present invention is not limited to this. For example, an emergency stop device (braking device) such as a hydraulic elevator, a linear motor elevator, and a self-propelled elevator The present invention is also applicable to the present invention.

Embodiment 4 In the above-described first to third embodiments, the material of the friction piece 2 is described as a ceramic material. However, in the present embodiment, the friction piece 2 is made of tungsten that exhibits a higher friction coefficient with respect to the brake body than the ceramic material. , Cobalt, titanium, nickel, chromium, tantalum,
Metals such as zirconium, boron, beryllium and molybdenum, and compounds such as metal nitrides, oxides, carbides and borides, and high heat-resistant ceramic materials such as alumina, zirconia, silicon nitride, silicon carbide, sapphire and nitride Use a composite material with aluminum or the like. Thereby, in addition to obtaining the same effects as those of the respective embodiments, the friction piece is excellent in heat resistance, and has a higher coefficient of friction with respect to the brake body as compared with the friction piece made of a ceramic material. In addition, it is possible to further increase the braking ability of the braking element.

[0031]

According to the present invention, there is provided an elevator braking apparatus comprising: a holder having a plurality of holes formed in a surface facing a sliding surface of a member to be braked; A brake element comprising a plurality of ceramic material friction pieces inserted and fixed in the respective holes of the holding body; and a pressing force generating mechanism for pressing the brake element against the brake body during an emergency stop. In the elevator braking system, the sliding surface of each of the plurality of friction pieces is made to coincide with the surface facing in parallel with the sliding surface of the braked body, so that the ceramic has excellent heat resistance but low toughness. Even if the material is used for the friction pieces, the individual friction pieces are less likely to break, and even if some of the friction pieces are broken or cracked, the other friction pieces will not be broken or cracked, Furthermore, the braking element and the It is possible to brake with a small pressing force to the braking element by the contact area between the moving body is increased, thereby to reduce the size and weight of the elevator brake system for highly reliable both heat resistance and impact resistance.

Further, since the plurality of friction pieces of the elevator braking device according to the present invention have chamfered or curved surfaces at the peripheral edges of their sliding surfaces, the impact force on the friction pieces during braking is reduced. Thus, it is possible to further reduce damage to the braking element, and to obtain a more reliable elevator braking apparatus.

Further, since the plurality of friction pieces of the elevator braking device according to the present invention have a plurality of grooves formed on their sliding surfaces, the frictional force between the brake element during operation and the braked body increases. In addition, it is possible to realize an elevator braking device that can surely perform emergency braking with a smaller pressing force.

Further, the plurality of friction pieces of the elevator braking device according to the present invention are a composite material of a ceramic material and a metal or metal compound material having a higher coefficient of friction than the ceramic material with respect to the brake target. Therefore, it is possible to further increase the braking ability of the braking element.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a brake element of an elevator braking device according to a first embodiment.

FIG. 2 is a diagram illustrating a configuration of a brake element of an elevator braking device according to a second embodiment.

FIG. 3 is a view for explaining the shape of a friction piece of an elevator braking device according to a second embodiment.

FIG. 4 is a view for explaining another modified example of the friction piece of the elevator braking device according to the second embodiment.

FIG. 5 is a diagram for explaining a shape of a friction piece of the elevator braking device according to the third embodiment.

FIG. 6 is a schematic diagram showing a configuration of a block brake.

FIG. 7 is a schematic diagram showing a configuration of a band brake.

FIG. 8 is a schematic diagram showing a configuration of a disc brake.

FIG. 9 is a diagram showing an example of a braking device applied to an elevator.

FIG. 10 is a view showing a structure of a braking body.

FIG. 11 is a diagram illustrating heat resistance of a ceramic material.

FIG. 12 is a view for explaining a detailed structure of the conventional brake element shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 braker 2 friction piece 2a chamfered portion 2b curved surface portion 2c groove 3 holder 5 wedge-shaped member 10 braked body (guide rail) 11 cage 12 rope 13 brake device 14 press spring 15 brake body

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasushi Chatani 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Mikatsu Hayashi 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Koei Matsukawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 3F304 DA45

Claims (4)

[Claims] 1. A holding body having a plurality of holes formed in a facing surface facing a sliding surface of a braked body, and a tip end protruding from the facing surface to the braked body side. An elevator braking apparatus comprising: a brake element including a plurality of ceramic material friction pieces inserted and fixed in a hole; and a pressing force generating mechanism that presses the brake element against the braked body during an emergency stop. The braking device for an elevator, wherein a sliding surface of each of the plurality of friction pieces is made to coincide with a surface facing the sliding surface of the body to be braked in parallel. 2. The braking device for an elevator according to claim 1, wherein the plurality of friction pieces have chamfered or curved surfaces at a peripheral edge of a sliding surface thereof. 3. A plurality of friction pieces having a plurality of grooves formed on a sliding surface thereof.
An elevator braking device according to claim 1. 4. The friction material according to claim 1, wherein the plurality of friction pieces are a composite material of a ceramic material and a metal or metal compound material having a higher coefficient of friction than the ceramic material with respect to the brake target. The elevator braking device according to any one of claims 3 to 3.