JP7804604B2 - Elevator brake device - Google Patents

Description

The present invention relates to a brake device for an elevator.

Lifts such as elevators and escalators are equipped with brake devices that brake the lifting machine. One type of brake device for elevators is the lever-type brake device. A lever-type brake device is a type of drum-type brake device that brakes the drum using the leverage of a lever. A lever-type brake device includes a drum that is connected to the elevator's lifting machine, a lining that contacts the outer surface of the drum to apply a braking force to the drum, and a shoe to which the lining is attached.

Traditionally, lever-type brake devices have used soft linings, but some manufacturers have discontinued production of soft linings due to environmental considerations in the manufacturing process. On the other hand, disc-type brake devices and direct-acting brake devices use hard linings that are resistant to surface pressure and highly durable.

One option is to change the lining used in lever-type brake devices from soft to hard. However, if the hard lining were to have the same shape as the soft lining, there is a risk that the hard lining would not be able to withstand the deformation caused by braking and would crack.

Patent Document 1 describes a technology for linings used in lever-type brake devices, in which a sintered metal lining (lining material) divided into multiple pieces is attached at intervals to a base having the same area as a conventional lining.

Japanese Patent Application Publication No. 10-110751

However, in the technology described in Patent Document 1, the surface of the base metal to which the lining is attached is smooth, and therefore the following problems may occur.
For example, if a lining is pressed against a rotating drum during an emergency stop of an elevator, frictional force is generated at the contact interface between the drum and the lining, and this frictional force causes the lining to receive a load in the direction of the drum rotation (hereinafter also referred to as "braking load"). The braking load is applied as a shear load to the lining's adhesive surface. For this reason, if the surface of the base is smooth, the lining will be more likely to peel off when subjected to the braking load.

The object of the present invention is to provide a brake device for elevators that can prevent lining peeling due to braking loads, even when using multiple divided linings.

In order to solve the above problems, for example, the configurations described in the claims are adopted.
The present application includes multiple means for solving the above-mentioned problems, and one such means is a brake device for an elevator comprising a drum connected to the hoist of the elevator, a lining that contacts the outer peripheral surface of the drum to apply a braking force to the drum, and a shoe to which the lining is attached, wherein the lining is divided into multiple parts in the circumferential direction of the drum, and the shoe has multiple grooves formed at intervals in the circumferential direction of the drum on an opposing surface that faces the outer peripheral surface of the drum, and the lining is attached to the shoe in a state where it is fitted into the grooves.

According to the present invention, even when a lining divided into a plurality of pieces is used, peeling of the lining due to braking load can be suppressed.
Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments.

FIG. 1 is a front view of an elevator brake device according to a first embodiment. 3 is a view showing a state in which a lining is attached to a shoe in the elevator brake device according to the first embodiment. FIG. FIG. 3 is a view of the shoe and lining as viewed from the left in FIG. 2 . 3 is a diagram illustrating a lining mounting structure at a portion P in FIG. 2. FIG. FIG. 10 is a view showing a state in which a lining is attached to a shoe in the elevator brake device according to the second embodiment. FIG. 4 is an enlarged view of the lining attachment state as viewed from the width direction of the shoe. 7 is a cross-sectional view taken along the line B-B in FIG. 6. 10A and 10B are diagrams illustrating the structure of a shoe and a lining provided in an elevator brake device according to a third embodiment. FIG. 11 is an enlarged view showing a state in which a lining is attached to a shoe in the elevator brake device according to the third embodiment. FIG. 10 is an enlarged view of the attached state of the lining in the elevator brake device according to the fourth embodiment, as viewed from the width direction of the shoe. 11 is a cross-sectional view taken along the line CC in FIG. 10. 10A and 10B are diagrams illustrating a method for attaching a lining in the fourth embodiment. FIG. 11 is a view showing a state in which a lining is attached to a shoe in the elevator brake device according to the fifth embodiment. FIG. 14 is a view of the shoe and lining as seen from the left in FIG. 13 . FIG. 10 is a diagram (part 1) for explaining a modified example. FIG. 10 is a diagram (part 2) for explaining a modified example. FIG. 10 is a diagram illustrating another modified example.

Embodiments of the present invention will be described in detail below with reference to the drawings. In this specification and drawings, elements having substantially the same function or configuration will be designated by the same reference numerals, and duplicate descriptions will be omitted.

First Embodiment
FIG. 1 is a front view of an elevator brake device according to a first embodiment.
1, elevator brake device 10 is a lever-type brake device that includes a drum 11 connected to an elevator hoist (not shown), a pair of levers 12 arranged on either side of drum 11, a spring 13 that biases the pair of levers 12, an electromagnetic force generating unit 14 that generates an electromagnetic force, a lining 15 that contacts the outer circumferential surface 11a of drum 11 to apply a braking force to drum 11, a shoe 16 to which lining 15 is attached, and a base 18 that supports a fulcrum 17 of lever 12. Elevator brake device 10 is used in elevators such as elevators and escalators.

The drum 11 is a metal member that rotates together with the output shaft of the hoist. The lever 12 is supported so that it can rotate freely around a fulcrum 17. The end 12a of the lever 12 is biased by a spring 13. The spring 13 biases the pair of levers 12 in a braking direction. The braking direction here refers to the direction in which the lining 15 is pressed against the outer peripheral surface 11a of the drum 11 via the shoe 16. Note that in Figure 1, two springs 13 bias the pair of levers 12 from both sides; however, it is also possible to bias the pair of levers in the braking direction with a single spring (not shown).

The electromagnetic force generating unit 14, for example (not shown), comprises an electromagnetic coil, a fixed iron core, and a movable iron core. When current flows through the electromagnetic coil due to energization, it generates an electromagnetic force that overcomes the biasing force of the spring 13. The pair of levers 12 are displaced in the direction opposite to the braking direction, i.e., in the direction that releases the brake, by the electromagnetic force generated by the electromagnetic force generating unit 14. Furthermore, when current is cut off from the electromagnetic force generating unit 14 and no current flows through the electromagnetic coil, the pair of levers 12 are displaced in the braking direction by the biasing force of the spring 13. In other words, the elevator brake device 10 is designed so that the brake is released only when the electromagnetic force generating unit 14 is energized.

The shoes 16 are arranged in pairs on both sides of the drum 11, similar to the levers 12 described above. The shoes 16 are made of metal, such as cast iron, and are formed in an arc shape to fit along the outer peripheral surface 11a of the drum 11. The shoes 16 are attached to the lever 12 with screws 19.

The lining 15 is made of a hard lining. Hard linings have a higher allowable surface pressure than soft linings. Hard linings and soft linings differ in the materials they are made of and the processing methods they are made from. Specifically, hard linings are made by blending inorganic fibers, organic fibers, specially formulated thermosetting synthetic resins, and fillers, and then pressurizing and heating this mixture to form a hard molded lining into a specified size. In contrast, soft linings are soft (semi-rigid) belt-like linings made by impregnating a fabric made from a woven mixture of special glass containing metal fibers with a special synthetic resin binder, drying, heating, and pressurizing the fabric to a specified size.

The lining 15 is divided into multiple pieces in the circumferential direction of the drum 11 (direction R in Figure 1). By using a lining 15 divided into multiple pieces in this way, cracking of the lining 15 can be suppressed even if the lining 15 is made of a hard lining. In this embodiment, as an example, the lining 15 is divided into three pieces in the circumferential direction of the drum 11, and these three linings 15 are attached to one shoe 16.

Fig. 2 is a diagram showing a state in which a lining is attached to a shoe in the elevator brake device according to the first embodiment, Fig. 3 is a diagram showing the shoe and lining as viewed from the left in Fig. 2, and Fig. 4 is a diagram explaining the lining attachment structure at part P in Fig. 2.
In addition, in Figure 1, the pair of shoes 16 are arranged symmetrically on the left and right sides with the drum 11 in between, but since their basic structure is the same, only one shoe 16 and the lining 15 attached to it will be explained here.

As shown in Figures 2 to 4, the shoe 16 has multiple grooves 22 on its facing surface 20, which faces the outer peripheral surface 11a of the drum 11. The facing surface 20 of the shoe 16 is formed concavely along the outer peripheral surface 11a of the drum 11. The grooves 22 are formed by recessing a portion of the facing surface 20 of the shoe 16. In this embodiment, three grooves 22 are formed on the facing surface 20 of the lever 12, corresponding to the number of divisions of the lining 15 (three in this example).

The three grooves 22 are formed at intervals in the circumferential direction of the drum 11 (direction R in Figure 1). A lining 15 fits into each groove 22. The grooves 22 are formed in the shape of a long strip in the width direction X (Figure 3) of the shoe 16. The width direction X of the shoe 16 is a direction parallel to the central axis of the drum 11. The grooves 22 are formed across the entire width of the shoe 16, and the lining 15 fits into the grooves 22 across the entire width of the shoe 16. In other words, the length of the grooves 22 and the length of the lining 15 in the X direction in Figure 3 are approximately the same as the width of the shoe 16.

As shown in FIG. 4, the depth Ld of the groove 22 is set smaller than the thickness Lt of the lining 15. The width Lw1 of the groove 22 is set slightly larger than the width Lw2 of the lining 15. The difference between the width Lw1 of the groove 22 and the width Lw2 of the lining 15 is, for example, approximately 0.1 mm to 1.0 mm at room temperature. This creates a gap corresponding to the above-mentioned dimensional difference (Lw1 - Lw2) at the mating portion between the lining 15 and the groove 22. When attaching the lining 15 to the shoe 16, the lining 15 can be fitted into the groove 22 from the left-right direction (indicated by the arrow) in FIG. 4. The groove 22 is formed across the entire width of the shoe 16. Therefore, when attaching the lining 15 to the shoe 16, the lining 15 can be fitted into the groove 22 by inserting the lining 15 into the groove 22 from the width direction X of the shoe 16.

In the elevator brake device 10 according to the first embodiment, when the electromagnetic force generating unit 14 is switched from a powered state to a de-powered state, the pair of levers 12 are displaced in the braking direction by the biasing force of the spring 13. As a result, each lining 15 is pressed against the outer peripheral surface 11a of the drum 11. When the lining 15 is pressed against the rotating drum 11, a frictional force is generated at the contact interface between the drum 11 and the lining 15, and this frictional force causes the lining 15 to receive a load in the direction of drum rotation, i.e., a braking load.

Here, as described above, the lining 15 is attached to the shoe 16 while fitted into the groove 22. Therefore, when a braking load is applied to the lining 15 by being pressed against the drum 11, this braking load can be borne by the fitting portion (hooking portion) between the lining 15 and the groove 22. This prevents the lining 15 from peeling off due to the braking load.

The lining 15 is also configured to be insertable into the groove 22 from the width direction X of the shoe 16. Therefore, when the wear of the lining 15 exceeds a predetermined amount and replacement is necessary, the lining can be replaced without disassembling the elevator brake device 10. Specifically, for example, the brake is released by pushing the end 12a of the lever 12 in the spring compression direction with a tool or the like against the biasing force of the spring 13. In this state, the old lining 15 is then pulled out of the groove 22, and a new lining 15 is inserted into the groove 22, thereby replacing the lining 15. This reduces the time and costs required for maintenance work on the elevator brake device 10, including lining replacement.

Second Embodiment
Fig. 5 is a view showing a state in which a lining is attached to a shoe in an elevator brake device according to a second embodiment, Fig. 6 is an enlarged view of the attached state of the lining as seen from the width direction of the shoe (direction A in Fig. 5), and Fig. 7 is a cross-sectional view taken along line B-B in Fig. 6.
The elevator brake device according to the second embodiment differs from the first embodiment in the lining mounting structure.

As shown in Figures 5 to 7, the lining 15 is fitted into a groove 22 formed in the shoe 16, as in the first embodiment described above. Two holders 24 are attached to each shoe 16 for each lining 15. The holders 24 are components that prevent the lining 15 from shifting in the length direction of the groove 22 (the X direction in Figure 5). The holders 24 are attached to both ends of the groove 22 in the length direction so as to sandwich the lining 15 from both sides in the X direction in Figure 5.

The holder 24 is attached to the shoe 16 with a hex bolt 25. More specifically, a threaded hole is formed in the bottom surface of the groove 22 of the shoe 16 corresponding to the attachment position of the holder 24, and a through-hole is formed in the holder 24 to allow the male threads of the hex bolt 25 to pass through. The holder 24 is then fixed to the shoe 16 by passing the hex bolt 25 through the through-hole of the holder 24 and engaging it with the threaded hole of the groove 22, and then tightening the hex bolt 25. Note that in this embodiment, the holder 24 is fixed using the hex bolt 25 as an example, but the fixing means is not limited to the hex bolt 25 and can be variously modified.

The length of the lining 15 in the X direction in Figure 5 is set shorter than the length of the groove 22, thereby ensuring space for attaching a holder at both longitudinal ends of the groove 22. Furthermore, as shown in Figure 7, the lining 15 has a stepped structure with a protrusion 151. Furthermore, the lining 15 has thin-walled portions 152 at both longitudinal ends of the lining 15. The protrusion 151 of the lining 15 is positioned so that it protrudes toward the drum 11 beyond the opposing surface 20 of the shoe 16. Therefore, when the electromagnetic force generating unit 14 is in a non-energized state, the protrusion 151 of the lining 15 is pressed against the outer peripheral surface 11a of the drum 11.

The holder 24 is made of a bent metal plate such as a plated steel plate. The holder 24 integrally comprises a fixed portion 241, a rising portion 242, and a pressing portion 243. The fixed portion 241 is fixed to the bottom surface of the groove 22 with a hexagonal bolt 25. The rising portion 242 rises vertically from the bottom surface of the groove 22 at a right angle to the fixed portion 241. The rising portion 242 also connects the fixed portion 241 and the pressing portion 243. The rising portion 242 is positioned in contact with or close to the longitudinal end surface 153 (Figure 7) of the lining 15 to prevent the lining 15 from shifting in the longitudinal direction of the groove 22. The pressing portion 243 is positioned parallel to the bottom surface of the groove 22 at a right angle to the rising portion 242. The retaining portion 243 is placed over the thin portion 152 of the lining 15, and in this state presses the lining 15 against the bottom surface of the recessed groove 22.

In the elevator brake device according to the second embodiment, in addition to the same effects as those in the first embodiment described above, the following effects can be obtained.
The elevator brake device according to the second embodiment includes a holder 24 that prevents the lining 15 from shifting in position along the length of the groove 22. This prevents the lining 15 from shifting in position due to repeated activation and release of the brake by the holder 24, thereby maintaining stable braking performance. Furthermore, since there is no need to fix the lining 15 to the shoe 16 with screws or the like, there is no need to drill holes in the lining 15.

The holder 24 also has a pressing portion 243 that presses the lining 15 against the bottom surface of the groove 22. This prevents the lining 15 from rattling due to the difference (Lw1-Lw2) between the width direction Lw1 of the groove 22 and the width dimension Lw2 of the lining 15, as described in the first embodiment with reference to Figure 4.

Third Embodiment
FIG. 8 is a diagram illustrating the structure of the shoe and lining provided in the elevator brake device according to the third embodiment, and FIG. 9 is an enlarged view showing the state in which the lining is attached to the shoe in the elevator brake device according to the third embodiment.
As shown in Figures 8 and 9, the shoe 16A has a plurality of grooves 22A. The lining 15A is fitted into the grooves 22A of the shoe 16A. The grooves 22A of the shoe 16A are formed in a dovetail shape. The lining 15A is formed in a trapezoid shape corresponding to the dovetail shape of the grooves 22A. An appropriate gap G (Figure 9) is provided at the fitting portion between the grooves 22A and the lining 15A. The presence of this gap G allows the lining 15A to be inserted into the grooves 22A in the width direction of the shoe 16A (the direction perpendicular to the plane of the paper in Figure 9).

As shown in Figure 9, the aforementioned gap G is the gap secured on both sides of the lining 15A when the lining 15A is pressed against the bottom of the groove 22A. At room temperature, the combined gap G is approximately 0.1 mm to 1.0 mm. Providing this gap G prevents stress from being generated at the interface between the lining 15A and the groove 22A due to thermal expansion of the lining 15A, for example, when the lining 15A thermally expands due to contact with the rotating drum 11, thereby preventing cracking of the lining 15A and the shoe 16A. Meanwhile, because lining replacement is performed when the lining 15A is not thermally expanding, the presence of the aforementioned gap G allows the lining 15A to be replaced without disassembling the elevator brake device. This effect can also be achieved in the first and second embodiments by providing a gap (approximately 0.1 mm to 1.0 mm at room temperature) at the interface between the lining 15 and the groove 22, equivalent to the difference between the width direction Lw1 of the groove 22 and the width dimension Lw2 of the lining 15.

Furthermore, in the third embodiment, the position of the lining 15A in the normal direction (left-right direction in Figure 9) of the opposing surface 20A of the shoe 16A is regulated by the engagement between the dovetail-shaped recessed groove 22A and the trapezoidal lining 15A. Therefore, peeling of the lining 15A due to braking load can be more effectively suppressed compared to the first embodiment described above.

In the third embodiment, as shown in Figure 9, the entire lining 15A is formed in a trapezoidal shape, but this is not limited to this. Only a portion of the lining 15A that fits into the dovetail-shaped recessed groove 22A may be formed in a trapezoidal shape.

Fourth Embodiment
FIG. 10 is an enlarged view of the elevator brake device according to the fourth embodiment, showing the state in which the lining is attached, as viewed from the width direction of the shoe, and FIG. 11 is a cross-sectional view taken along the line CC of FIG.
The elevator brake device according to the fourth embodiment is similar to the third embodiment in that the groove 22A of the shoe 16A is dovetail-shaped and the lining 15A is trapezoidal to correspond to this dovetail shape. However, the fourth embodiment differs from the third embodiment in that a holder 24 is attached to the shoe 16A and the lining 15A has a stepped structure to accommodate the attachment of the holder 24.

The holder 24 has the same structure as in the second embodiment described above (Figures 6 and 7). The lining 15A has a convex portion 151A, a thin portion 152A, and an end surface 153A. The fixing portion 241 of the holder 24 is fixed to the bottom surface of the recessed groove 22A by a hexagonal bolt 25. The rising portion 242 of the holder 24 is positioned in contact with or close to the end surface 153A of the lining 15A. The pressing portion 243 of the holder 24 is positioned over the thin portion 152A of the lining 15A, and in this state presses the lining 15A against the bottom surface of the recessed groove 22A.

In the fourth embodiment, when attaching the lining 15A to the shoe 16A, as shown in Figure 12, the lining 15A is fitted into the groove 22A by inserting it into the groove 22A from a direction parallel to the width direction X of the shoe 16. At this time, the insertion amount of the lining 15A is adjusted so that the screw hole 26 formed in the bottom surface of the groove 22A is not hidden by the lining 15A. Next, as shown in Figures 10 and 11, the holder 24 is attached to the shoe 16A with the hexagon bolt 25.

The elevator brake device according to the fourth embodiment achieves the same effects as the second and third embodiments described above. Furthermore, when the holder 24 is attached as described above, the surface 243a of the pressing portion 243 of the holder 24 comes into contact with the outer peripheral surface 11a of the drum 11 when the wear amount of the lining 15A reaches a predetermined amount t (Figure 11). In this case, if the surface 243a of the pressing portion 243, which corresponds to the contact surface, is colored with paint or other coating material, when the surface 243a of the pressing portion 243 comes into contact with the outer peripheral surface 11a of the drum 11, the color transfers from the surface 243a of the pressing portion 243 to the outer peripheral surface 11a of the drum 11 at the point of contact, thereby changing the color of the outer peripheral surface 11a of the drum 11.

As a result, during periodic inspections of the elevator brake device, it is possible to determine whether the wear amount of the lining 15A has reached a predetermined amount t by checking whether the color of the outer peripheral surface 11a of the drum 11 has changed. This effect can also be achieved when the surface of the pressing portion 243 of the holder 24 in the second embodiment described above is colored. Note that only the surface 243a of the pressing portion 243 of the holder 24 may be colored, or the entire holder 24, including the surface 243a of the pressing portion 243, may be colored. If the entire holder 24 is colored by painting or the like, the bent metal plate that makes up the holder 24 does not need to be plated.

Fifth Embodiment
Fig. 13 is a view showing a state in which a lining is attached to a shoe in an elevator brake device according to a fifth embodiment, and Fig. 14 is a view of the shoe and lining as viewed from the left in Fig. 13 .
The elevator brake device according to the fifth embodiment is similar to the third embodiment in that the groove 22A of the shoe 16A is dovetail-shaped and the lining 15A is trapezoidal to correspond to this dovetail shape. However, the fourth embodiment differs from the third embodiment in that a holder 24B is attached to the shoe 16A.

As shown in Figure 14, the holder 24B is formed in a flat plate shape and is attached to the end face of the shoe 16A in the width direction X with screws 27. As shown in Figure 13, the holder 24B is formed in an arc shape so that it overlaps each of the three divided linings 15A. This allows the common holder 24B to suppress misalignment of each lining 15A in the length direction of the groove 22A (X direction in Figure 14). This reduces the number of parts and the assembly time compared to suppressing misalignment of each lining 15A with individual holders 24 (see, for example, Figures 5 to 7, 10, and 11). The holder 24B is attached to the end face of the shoe 16A so as to sandwich the lining 15A in the width direction X of the shoe 16A. This facilitates the installation of the holder 24B.

In the fifth embodiment, the position of each lining 15A in the longitudinal direction of the groove 22A is held down by a common holder 24B. However, as a modified example, as shown in Figures 15 and 16, a configuration may be adopted in which a holder 24C having a retaining portion 243C is attached to the end face of the shoe 16A with a screw 27. In this configuration, the retaining portion 243C of the holder 24C is positioned over the thin-walled portion 152A of each lining 15A, and in this state, each lining 15A is pressed against the bottom surface of the groove 22A.

As another variation, as shown in Figure 17, a configuration may be adopted in which a holder 24D having a retaining portion 243D is attached to the opposing surface 20A of the shoe 16A with a screw 28. As in the fourth embodiment, the lining 15A has a convex portion 151A and a thin portion 152A (Figures 10 and 11). The retaining portion 243D of the holder 24D is positioned over the thin portion 152A of each lining 15A, and in this state presses each lining 15A against the bottom surface of the groove 22A. Even with this configuration, the common holder 24D prevents misalignment of each lining 15A in the length direction of the groove 22A (X direction in Figure 17). This reduces the number of parts and the labor required for assembling the parts.

The present invention is not limited to the above-described embodiments, but includes various modifications. For example, the above-described embodiments are described in detail to facilitate understanding of the present invention, but the present invention is not necessarily limited to including all of the configurations described in the above-described embodiments. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to delete part of the configuration of each embodiment, add other configurations, or replace it with other configurations.

10...Elevator brake device, 11...Drum, 11a...Outer surface, 15, 15A...Lining, 16, 16A...Shoe, 20, 20A...Opposite surface, 22, 22A...Groove, 24, 24B, 24C, 24D...Holder, 243, 243C, 243D...Pressing portion, 243a...Surface (contact surface), G...Gap

Claims (9)

A brake device for an elevator comprising: a drum connected to a hoist of an elevator; a lining that contacts an outer peripheral surface of the drum to apply a braking force to the drum; and a shoe to which the lining is attached,
The lining is divided into a plurality of sections in the circumferential direction of the drum,
The shoe has a surface facing the outer circumferential surface of the drum, and a plurality of grooves are formed at intervals in the circumferential direction of the drum,
The lining is attached to the shoe in a state where it is fitted into the recessed groove. The recessed groove is formed in a dovetail groove shape,
The elevator brake device according to claim 1 , wherein at least a portion of the lining is formed in a trapezoidal shape corresponding to the dovetail groove shape. The elevator brake device according to claim 1, wherein the lining is configured to be insertable into the recessed groove from a width direction of the shoe. The elevator brake device according to claim 1, wherein a gap is provided at a fitting portion between the lining and the recessed groove. The elevator brake device according to claim 1 , further comprising a holder that prevents the lining from shifting in position in the length direction of the groove. The elevator brake device according to claim 5, wherein the holder has a pressing portion that presses the lining against a bottom surface of the recessed groove. The elevator brake device according to claim 5, wherein the holder has a contact surface that comes into contact with the outer peripheral surface of the drum when the wear amount of the lining reaches a predetermined amount, and at least the contact surface is colored. The elevator brake device according to claim 5, wherein the positional deviation of each of the plurality of divided linings is suppressed by the common holder. The elevator brake device according to claim 5, wherein the holder is attached to an end surface of the shoe so as to sandwich the lining in the width direction of the shoe.