HK1138826A1 - Windlass for elevator - Google Patents

Abstract

The present invention provides a windlass for an elevator, capable of reducing an abrasion powder adhering amount on a brake face. A circumferential face of a rotor (51) is used as brake faces (3a, 3b), wherein a brake shoe (2a) slides on the brake face (3a) and a brake shoe (2b) slides on the brake face (3b). thereby, although the brake device is provided with two set of brake mechanisms, each brake shoe slides on each brake face and it is capable of reducing the abrasion powder by half comparing with in the existent technology wherein the two brake shoes slide on a same brake face. Thus, itis capable of reducing the abrasion powder adhering amount on the brake face and obtaining the brake device with a stable brake force and a high reliability.

Description

Hoist for elevator

Technical Field

The present invention relates to a hoist for an elevator, which has a brake device for generating a braking force.

Background

An elevator hoist is generally provided with a motor for driving an elevating body and a braking device that is a braking unit for braking the movement of the elevating body. The braking device includes a device for statically holding the vertically movable body and a device for emergency braking of the vertically movable body when the vertically movable body abnormally increases in speed. In order to improve the reliability of the brake device, it is specified in foreign standards that two sets of brake mechanisms for braking and releasing braking must be provided, and each brake device must be capable of independently functioning as a brake.

As a conventional brake device provided with two sets of brake mechanisms, there is an electromagnetic brake device provided with: first and second brake arms having brake shoes provided on a braking surface of the rotor and one end portion rotatably supported; a brake spring provided at the other end of the first and second brake arms, for pressing the brake shoe against the brake surface to brake the rotor; an electromagnetic device, which is composed of an electromagnet and an iron sheet, wherein the electromagnet is composed of a magnet yoke and an electromagnetic winding, and is arranged to act in a direction connecting the other ends of the first and second brake arms, the iron sheet is arranged opposite to the magnetic pole surface of the electromagnet, when the electromagnet is electrified, the electromagnetic device overcomes the spring force of the brake spring by utilizing the electromagnetic attraction force generated when the electromagnet is electrified, thereby driving the first and second brake arms and releasing the brake of the rotor by releasing the pressing force of the brake shoe, in the electromagnetic brake device, two sets of electromagnetic devices are provided, each of which is composed of an electromagnet and an iron piece, one of the electromagnet and the iron piece is fixed, and the other is movable, the first and second brake arms are driven by an electromagnet or an iron piece on the movable side (see, for example, patent document 1).

[ patent document 1 ] Japanese patent laid-open No. 2006-266362 (paragraphs 0057 to 0060, FIG. 1).

In the above-described conventional art, the reliability of the brake device is improved by providing two sets of brake mechanisms, but the conventional art does not consider how to suppress adhesion of brake shoe wear powder to the sliding surface due to sliding between the brake shoe and the rotor, nor how to promote discharge of the wear powder. That is, since abrasion powder generated by sliding between the brake shoe and the rotor may adhere to the braking surface, and then the braking device may not obtain a stable braking force, it is necessary to further improve the reliability of the braking device.

Disclosure of Invention

The present invention has been made in view of the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide an elevator hoist capable of reducing the amount of abrasion powder adhering to a braking surface.

In order to achieve the above object, a first aspect of the present invention provides a hoisting machine for an elevator, comprising: a sheave around which a sling is wound; a rotor that rotationally drives the sheave; and a brake device that has a pair of brake shoes disposed to face the rotor and generates a braking force by pressing the rotor with the brake shoes, wherein an inner circumferential surface or an outer circumferential surface of the rotor is used as a braking surface, and the brake shoes slide at different positions in a width direction of the braking surface.

In the invention according to the first aspect of the invention having the above configuration, the braking surface provided on the rotor is divided into two in the width direction, that is, in the axial direction of the hoisting machine, and the pair of brake shoes are slid on the respective braking surfaces. Thus, the amount of brake shoe wear dust adhering to one braking surface can be reduced by about half as compared with the conventional technique in which two brake shoes brake one braking surface.

In the invention according to a second aspect of the present invention, two annular portions having different diameters are provided on an inner circumferential surface or an outer circumferential surface of the rotor to form the braking surface.

In the invention according to the second aspect of the present invention having the above configuration, two annular portions having different diameters are provided on the inner peripheral surface or the outer peripheral surface of the rotor, and two braking surfaces are formed by the annular portions. In this way, since the braking surfaces are at different height positions, abrasion powder generated on one braking surface is less likely to affect the other braking surface.

In the invention according to the third aspect of the present invention, the diameter of the annular portion on the sheave side is set smaller than the diameter of the annular portion on the side opposite to the sheave.

In the invention according to the third aspect of the present invention having the above-described configuration, by setting the diameter of the annular portion on the pulley side to be smaller than the diameter of the annular portion on the opposite side to the pulley, the wear powder can be more easily discharged to the pulley side.

In the invention according to a fourth aspect of the present invention, the outer peripheral surface of the rotor is made the braking surface, and the braking surface is provided so as to be inclined, and the inclination is formed by making the outer peripheral diameter of the braking surface on the rope wheel side smaller than the outer peripheral diameter of the braking surface on the opposite side to the sheave.

In the invention relating to the fourth aspect of the present invention having the above-described configuration, the wear powder adhering to the braking surface is more easily discharged to the sheave side by the inclined shape of the braking surface and the action of the wind blowing on the surface of the braking surface.

A fifth aspect of the present invention is the one in which a housing that fixedly supports the rotor has an opening that is provided so as to cover the rotor, and the diameter of the opening is set so that the diameter on the sheave side is larger than the diameter on the opposite side to the sheave.

In the invention according to the fifth aspect of the invention having the above configuration, since the rotor is covered with the opening of the housing, scattering of abrasion powder can be prevented. Further, since wind is generated when the sheave starts rotating, the abrasion powder can be discharged to a predetermined position on the sheave side along the inclined portion by the action of the wind and the gravity.

In the invention according to a sixth aspect of the present invention, an annular groove portion is provided in the rotor so as to separate the one braking surface from the other braking surface.

In the invention according to the sixth aspect of the present invention having the above-described configuration, since the annular groove portion is provided between the one braking surface and the other braking surface, the abrasion powder adhering to the one braking surface is less likely to move to the other braking surface.

In a seventh aspect of the present invention, the outer peripheral surface of the rotor is used as the braking surface, and an annular step portion having a larger diameter than the braking surface is formed at an end of the rotor opposite to the sheave.

In the invention according to the seventh aspect of the present invention having the above-described configuration, since the annular step portion having a larger diameter than the braking surface is formed at the end of the rotor on the side opposite to the sheave, the abrasion powder generated on the braking surface can be prevented from entering the adjacent equipment.

In an eighth aspect of the present invention, the brake shoe has an inclined portion parallel to the inclined portion of the braking surface.

In the invention according to the eighth aspect of the present invention having the above configuration, the brake shoe can be configured to conform to the brake surface that is provided obliquely.

Effects of the invention

According to the present invention, even if two sets of brake mechanisms are installed in the brake device, since one brake shoe slides on one braking surface, abrasion powder adhering to one braking surface can be reduced by about half as compared with the prior art in which two brake shoes slide on one braking surface. Further, the adhered abrasion powder is more easily discharged to the sheave side by the tapered shape of the braking surface and the wind blowing on the surface of the braking surface. This can further reduce the amount of wear powder adhering to the braking surface, and can provide a highly reliable braking device with stable braking force.

Drawings

Fig. 1 is a front view showing a first embodiment of an elevator hoist according to the present invention.

Fig. 2 is a horizontal sectional view of the elevator hoist viewed from above along the line a-a' of fig. 1.

Fig. 3 is a horizontal sectional view of a main portion along line a-a' of fig. 1, showing a second embodiment of an elevator hoist according to the present invention.

Fig. 4 is a longitudinal sectional view taken along line B-B' of fig. 1, showing a third embodiment of an elevator hoist according to the present invention.

Description of the symbols

1a, 1b brake lever

2a, 2b brake shoes

3 braking surface

3a, 3b braking surface

4 sling

5 rope wheel

6a, 6b rod piece fulcrum

7a, 7b electromagnetic winding

8a, 8b brake spring

10 casing

13 permanent magnet

16 encoder shaft

17 fixed shaft

18 bearing

20 encoder

21 opening part

31 annular step part

32 groove part

41 hoistway wall

51 rotor

52 stator core

53 inspection hole

a maximum thickness dimension of brake shoe

b width dimension of inspection hole

e height dimension of annular step part

Diameter of D1 rotor

Diameter of D2 sheave

Theta 1 taper angle of opening part of case

Cone angle of theta 2 rotor

Theta 3 taper angle of brake shoe

Detailed Description

An embodiment of an elevator hoisting machine according to the present invention will be described below with reference to the drawings.

Fig. 1 is a front view showing a first embodiment of a hoisting machine for an elevator according to the present invention,

fig. 2 is a horizontal sectional view of the elevator hoist as viewed from above along the line a-a in fig. 1.

The hoist of the present embodiment is, for example, a hoist used in a machine room-less elevator, and is provided in a hoistway, and includes a sheave 5 around which a hoist rope 4 is wound, a rotor 51 provided integrally with the sheave 5, and a braking device for braking the rotor 51. Further, the rotor configuration of the present embodiment is an external rotor configured such that the stator core 52 is disposed inside the rotor 51, and the rotor 51 rotates outside the stator core 52.

In the braking device, two annular portions having different diameters are provided on an outer peripheral surface of a rotor 51 to form braking surfaces 3a, 3b, and the braking device includes: a pair of brake shoes 2a, 2 b; a pair of brake levers 1a, 1b, the brake shoes 2a, 2b being fixed to one ends of the pair of brake levers 1a, 1b, respectively; brake lever fulcrum points 6a, 6b which are rotation fulcrum points of the brake levers 1a, 1 b; electromagnetic windings 7a, 7b for driving the brake levers 1a, 1b at the other ends of the brake levers 1a, 1 b; and brake springs 8a and 8b for pressing the brake shoes 2a and 2b against the braking surfaces 3a and 3 b. When the electromagnetic windings 7a, 7b are not energized, the brake shoes 2a, 2b are pressed against the brake surfaces 3a, 3b by the brake springs 8a, 8b, so that the elevator car, not shown, is kept stationary. On the other hand, when the elevator car is moved up and down, the lower ends of the brake levers 1a and 1b are attracted by energizing the electromagnetic windings 7a and 7b, and the brake shoes 2a and 2b are separated from the braking surfaces 3a and 3 b. As described above, the brake device is provided with two sets of brake mechanisms for braking and releasing the brake, and each brake mechanism can function independently, so that the reliability of the brake device is improved.

In the present embodiment, as described above, the braking surfaces 3a and 3b are provided on the outer peripheral surface of the rotor 51, the braking surfaces 3a and 3b are divided into two in the axial direction of the hoisting machine, and the pair of brake shoes 2a and 2b provided on the left and right sides of the braking surfaces are pressed against the different braking surfaces 3a and 3b, respectively. I.e. the brake shoe 2a slides on the brake surface 3a, while the brake shoe 2b slides on the brake surface 3 b. Further, diameters of two annular portions constituting the braking surfaces 3a, 3b are set to be different from each other, and a stepped portion is formed between the braking surface 3a and the braking surface 3 b. This prevents abrasion powder, dust, and the like adhering to the braking surfaces 3a and 3b on one side from moving to the braking surfaces 3a and 3b on the other side. In this case, the movement of abrasion powder, dust, and the like can be sufficiently prevented by providing a diameter difference of several millimeters between the two annular portions. Further, by using the brake springs 8a and 8b of the same specification and adjusting the pressing force in accordance with the annular portion having a small diameter, it is not necessary to change the specifications of the pair of brake springs 8a and 8b and the electromagnetic coils 7a and 7 b.

Generally, the smaller the diameter D2 of the sheave 5, the smaller the braking torque required by the braking device. On the other hand, the larger the diameter D1 of the rotor 51, the smaller the pressing force required by the brake shoes 2a and 2 b. That is, the larger D2/D1 is, the more compact the brake device can be. In the configuration of the external rotor, since the rotor 51 rotates outside the stator core 52, D2/D1 is easily increased. This can facilitate the downsizing of the brake shoes 2a and 2 b. In the present embodiment, since the braking surfaces 3a and 3b are divided in the axial direction of the hoisting machine, the widths of the brake shoes 2a and 2b are also reduced. If the brake shoes 2a, 2b can be made smaller, it is easy to control the length in the circumferential direction to the minimum, and the different braking surfaces 3a, 3b are pressed by the brake shoes 2a, 2b having a smaller width.

As shown in fig. 2, the hoisting machine is disposed so that the sheave 5 faces the elevator shaft wall 41. The sheave 5 and the rotor 51 are integrally formed, and the rotational motion thereof is transmitted to the side opposite to the sheave by the encoder shaft 16. The shaft end of the encoder shaft 16 is directly connected to an encoder 20 provided at the end, and the rotational amount is detected by the encoder 20 to control the rotational driving of the hoisting machine. The stator core 52 is disposed in the housing 10, and the magnetic attraction force between the permanent magnet 13 attached to the inner periphery of the rotor 51 and the stator core 52 is controlled to perform a rotational motion. The sheave 5 and the rotor 51 are rotatably attached to the fixed shaft 17 by a bearing 18. Further, an annular step portion 31 having a larger diameter than the braking surfaces 3a and 3b is formed at an end portion of the rotor 51 opposite to the sheave. That is, the annular step portion 31 is higher than the braking surface 3a by a dimension e.

According to the first embodiment, although two sets of brake mechanisms are provided in the brake device, since one brake shoe slides on one braking surface, that is, the brake shoe 2a slides on the braking surface 3a and the brake shoe 2b slides on the braking surface 3b, abrasion powder adhering to one braking surface can be reduced by about half as compared with the case where two brake shoes slide on one braking surface in the related art. Further, since the braking surfaces 3a and 3b are different in height from each other, abrasion powder generated on one braking surface 3a or 3b hardly affects the other braking surface 3a or 3 b. Further, by setting the diameter of the annular portion constituting the braking surface 3b on the sheave side to be smaller than the diameter of the annular portion constituting the braking surface 3a on the side opposite to the sheave, the wear powder is more easily discharged to the sheave side. This can reduce abrasion powder adhering to the braking surfaces 3a and 3b, and can obtain a highly reliable braking device with stable braking force. Further, an annular step portion 31 is formed at the end of the rotor 51 opposite to the sheave, and the outer periphery of the step portion 31 is brought close to the housing 10, whereby abrasion powder generated on the braking surface 3a can be prevented from being mixed into the motor.

Fig. 3 is a horizontal sectional view of a main portion along line a-a' of fig. 1, showing a second embodiment of an elevator hoist according to the present invention. In fig. 3, the same portions as those described above are denoted by the same reference numerals.

As shown in fig. 3, the hoist according to the second embodiment is formed such that the outer peripheral surfaces of the rotor 51 are the braking surfaces 3a and 3b, and the braking surfaces 3a and 3b are formed in an inclined shape, and the inclination is formed by making the outer peripheral diameter of the braking surface 3b on the rope wheel side smaller than the outer peripheral diameter of the braking surface 3a on the opposite side to the sheave. That is, the braking surfaces 3a, 3b have a gentle inclination with a taper angle θ 2 such that the diameter thereof gradually decreases toward the sheave 5 side. The inclination can be formed by machining together the cutting work of the braking surfaces 3a, 3 b.

The rotor 51 is provided with an annular groove portion 32, and the groove portion 32 separates the one braking surface 3a from the other braking surface 3 b.

The brake shoe 2a has an inclined portion parallel to the inclined portion of the braking surface 3a, that is, the taper angle θ 3 of the inclined portion of the brake shoe 2a is the same as the taper angle θ 2 of the braking surface 3a, and satisfies the relationship that the taper angle θ 2 is equal to the taper angle θ 3. When a spherical structure (not shown) that can match the taper angle θ 2 is provided on the back surface of the brake shoe 2a, the taper angle θ 2 ≠ taper angle θ 3 may be provided.

In the second embodiment, when the sheave 5 rotates, a negative pressure portion is formed inside the motor, so that air flows from the inside of the motor to the outside of the motor, thereby generating wind. That is, when the external rotor is used, wind flowing on the outer surface of the rotor 51 can be generated. If a hole, not shown, is opened in the casing 10 to provide a portion for sucking air from the outside, the air volume becomes larger. Therefore, the abrasion powder adhering to the braking surfaces 3a and 3b can be more easily discharged toward the sheave side by the interaction between the wind and the inclination of the braking surfaces 3a and 3 b.

In addition, as shown in fig. 2, in the arrangement in which the sheave 5 and the elevating path wall 41 are provided to face each other, the gap between the elevating path wall 41 and the hoisting machine is narrow, and a maintenance worker cannot enter the gap, and therefore, the replacement work of the brake shoe 2a is performed from the housing 10 side. Similarly, the worn state of the brake shoe 2a and the state of the braking surface 3a are also checked from the housing 10 side. Therefore, the housing 10 is provided with an inspection hole 53 for exchanging the brake shoe 2a and checking the state. The inspection hole 53 is provided with a dimension b that is much larger than the thickness dimension a of the brake shoe 2 a. This makes it possible to easily perform the inspection and replacement work of the brake shoe 2a by visual inspection. In the motor using the built-in rotor not shown, since the braking surface is located inside the rotor, two surfaces can be formed on the braking surface in the same manner. Further, visual inspection and processing of the housing side can be facilitated by setting the braking diameter on the side opposite to the sheave to be larger than the braking diameter on the sheave side.

According to the second embodiment, the abrasion powder adhering to the braking surfaces 3a, 3b can be easily discharged toward the sheave side by the interaction of the tapered shape of the braking surfaces 3a, 3b and the wind blowing on the surfaces of the braking surfaces 3a, 3 b. Further, since the annular groove portion 32 is provided between the braking surfaces 3a and 3b, abrasion powder adhering to one braking surface is less likely to move to the other braking surface. This can further reduce the amount of wear debris adhering to the braking surfaces 3a and 3b, and can provide a highly reliable braking device with stable braking force.

Fig. 4 is a longitudinal sectional view taken along line B-B' of fig. 1, showing a third embodiment of an elevator hoist according to the present invention. The same reference numerals are used for the same portions as described above.

As shown in fig. 4, in the hoisting machine of the third embodiment, the housing 10 for supporting the suspended load of the elevator car by the sheave 5, the rotor 51, and the fixed shaft 17 has an opening 21, and the opening 21 is provided so as to cover the rotor 51. The diameter of the opening 21 is set larger on the sheave side than on the opposite side. That is, the housing 10 has an inclination with a taper angle θ 1 such that its diameter gradually increases toward the sheave 5 side.

In the third embodiment, the abrasion powder is scattered in the tangential direction of the outer periphery of the rotor 51 with the rotation of the sheave 5, and the abrasion powder is adhered to the braking surface 3 after the sheave 5 is stopped. When the sheave 5 starts rotating again, as described above, since wind is generated, abrasion powder is discharged to the sheave side along the inclined portion of the braking surface 3 by the action of the wind and gravity. On the other hand, in the lower half surface of the rotor 51, particularly the lowermost portion, when the sheave 5 is stopped, abrasion powder falls down to the housing 10 side due to the action of gravity. In the present embodiment, since the housing 10 is provided with the inclined portion opposite to the rotor 51 as described above, the abrasion powder accumulated on the housing 10 is discharged downward of the sheave 5 by the interaction of the gravity and the wind generated by the rotation of the sheave 5.

According to the third embodiment, since the rotor 51 is covered with the opening 21 of the housing 10, scattering of abrasion powder can be prevented. Further, since wind is generated when the sheave 51 starts rotating, the abrasion powder is discharged to a predetermined position on the sheave side along the inclined portion by the action of the wind and the gravity.

Claims (8)

1. A hoist for an elevator, comprising: a sheave around which a sling is wound; a rotor that rotationally drives the sheave; a brake device having a pair of brake shoes disposed opposite to the rotor and generating a braking force by pressing the rotor with the brake shoes, the elevator hoist being characterized in that,

the brake shoes slide at different positions in the width direction of the braking surface, with the inner circumferential surface or the outer circumferential surface of the rotor being the braking surface.

2. The hoisting machine for elevator according to claim 1,

two annular portions having different diameters are provided on an inner peripheral surface or an outer peripheral surface of the rotor to form the braking surface.

3. The hoisting machine for elevator according to claim 2,

the diameter of the loop portion on the sheave side is set smaller than the diameter of the loop portion on the side opposite to the sheave.

4. The hoisting machine for elevator according to claim 1,

the outer peripheral surface of the rotor is made to be the braking surface, and the braking surface is provided to be inclined, and the inclination is formed by making the outer peripheral diameter of the braking surface on the rope wheel side smaller than the outer peripheral diameter of the braking surface on the opposite side to the sheave.

5. The hoisting machine for elevator according to claim 1,

the housing that fixedly supports the rotor has an opening that is disposed so as to cover the rotor, and the diameter of the opening is set to be larger on the sheave side than on the opposite side to the sheave.

6. The hoisting machine for elevator according to claim 1,

the rotor is provided with an annular groove portion for partitioning the braking surface on one side from the braking surface on the other side.

7. The hoisting machine for elevator according to claim 1,

the outer peripheral surface of the rotor is used as the braking surface, and an annular stepped portion is formed at an end portion of the rotor opposite to the sheave, and the diameter of the annular stepped portion is larger than that of the braking surface.

8. The hoisting machine for elevator according to claim 4,

the brake shoe has an inclined portion parallel to the inclined portion of the braking surface.