Elevator brake switch mechanism

Abstract

To provide a brake switch mechanism that allows easy confirmation of an operating point of a microswitch while keeping the stroke of a brake plunger small.SOLUTION: There is provided a brake switch mechanism 30 that is installed on a brake device 20 of an elevator hoist 10 and detects braking or releasing of the brake device 20, comprising: a rotating operation piece 31 that rotates by the reciprocating motion of a brake plunger 27; and a microswitch 40 that has a switch lever 42 rotatably supported by a housing 41 of the microswitch 40, engaging with an engaging portion 31B of the rotating operation piece 31, and rotating by the rotation of the rotating operation piece 31, and opens and closes a connected electric circuit by rotating the switch lever 42.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a brake switch mechanism provided in a brake device of an elevator hoist, which detects braking or release of the brake device.

Background Art

[0002] A brake switch for detecting braking or release of a brake device and transmitting it to a control device of an elevator is provided in the brake device of an elevator hoist (for example, Patent Document 1). As the brake switch, a microswitch in which contacts are opened and closed by pressing a switch lever to open and close an electric circuit is used.

[0003] In the brake switch, the switch lever of the microswitch engages with the brake plunger of the brake device, and the switch lever is pressed by the reciprocating motion of the brake plunger to open and close the contacts. In the maintenance and inspection work of the brake switch, it is confirmed whether the operating point of the microswitch exists within the range of the reciprocating motion of the brake plunger.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in many cases, the length of the reciprocating motion of the brake plunger (hereinafter referred to as stroke) is small (for example, 3 mm). In the maintenance and inspection work of the brake switch, it is difficult to confirm the operating point of the brake switch within the range of a small stroke, and a high level of skill of the operator is required.

[0006] On the other hand, when the stroke of the brake plunger is increased, other problems occur, such as an increase in the operating noise during braking of the brake device, an increase in the impact of the brake plunger during emergency stop, and an increase in the wear of the plunger bush of the brake plunger.

[0007] An object of the present invention is to provide an elevator brake switch mechanism capable of easily confirming the operating point of a microswitch while reducing the stroke of a brake plunger.

Means for Solving the Problems

[0008] The elevator brake switch mechanism according to the present invention is an elevator brake switch mechanism provided in the brake device of the hoisting machine of the elevator and detecting the braking or release of the brake device. The brake device includes a brake drum fixed to the drive shaft of the hoisting machine, a brake pad slidably contacting the outer peripheral surface of the brake drum, an arm supporting the brake pad and biased by a spring to press the brake pad against the brake drum, and a brake plunger reciprocating by electromagnetic force to move the arm in a direction in which the brake pad separates from the brake drum via a rotation lever. The elevator brake switch mechanism has a rotation fulcrum rotatably supported by a support beam fixed to the hoisting machine, a rotation operation piece that locks with the brake plunger between the rotation fulcrum and the tip end portion and rotates by the reciprocating motion of the brake plunger, a switch lever rotatably supported by the microswitch housing, engaging with the tip end portion of the rotation operation piece, and rotating by the rotation of the rotation operation piece, a slider provided on the housing and pressed by the rotation of the switch lever, and a conductive movable piece disposed inside the housing and contacting or separating from a terminal by being pressed by the slider. The elevator brake switch mechanism further includes a microswitch that opens and closes an electric circuit connected by the rotation of the switch lever.

[0009] In the elevator brake switch mechanism according to the present invention, it is preferable to further include a scale for confirming the amount of movement of the tip end portion of the rotation operation piece.

Effects of the Invention

[0010] According to the brake switch mechanism of the elevator according to the present invention, the operating point of the microswitch can be easily confirmed while reducing the stroke of the brake plunger.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0012] Hereinafter, an example of an embodiment of the present invention will be described in detail. In the following description, specific shapes, materials, directions, numerical values, etc. are examples for facilitating the understanding of the present disclosure, and can be appropriately changed according to applications, purposes, specifications, etc.

[0013] Using FIGS. 1 and 2, the hoisting machine 10 of an elevator provided with a brake switch mechanism 30 which is an example of the present embodiment will be described. FIG. 1 is a side view showing the hoisting machine 10. FIG. 2 is a view seen from the arrow A in FIG. 1 showing a state where the electric motor 13 of the hoisting machine 10 is removed.

[0014] Hereinafter, with the vertical direction being the up - down direction, the direction parallel to the drive shaft 12 of the hoist 10 being the front - rear direction, and the direction orthogonal to both the up - down direction and the front - rear direction being the width direction, the hoist 10 will be described. Also, each side in the width direction toward the front side is defined as the left - hand side and the right - hand side respectively.

[0015] The hoist 10 is a device for raising and lowering a car and a counterweight, each suspended at both ends of the main rope of the elevator, along their respective rails. The hoist 10 is provided in a machine room directly above the hoistway of the elevator. As shown in FIGS. 1 and 2, the hoist 10 includes a sheave 11 around which the main rope is wound, a drive shaft 12 that rotates the sheave 11 via a transmission mechanism, an electric motor 13 that drives the drive shaft 12, a casing 15 that houses the transmission mechanism, and a brake device 20 that brakes the rotation of the drive shaft 12. Details of the brake device 20 will be described later.

[0016] Using FIGS. 1 to 3, the brake device 20 provided with a brake switch mechanism 30, which is an example of the present embodiment, will be described. FIG. 3 is a detailed view of the brake device 20 as seen from the arrow B in FIG. 1.

[0017] Hereinafter, as shown in FIG. 3, in the above - described front - rear direction, when the brake device 20 is released, the direction in which the brake plunger 27 moves is defined as the front side, and when the brake device 20 is braking, the direction in which the brake plunger 27 moves is defined as the rear side, and the brake device 20 will be described.

[0018] As shown in FIGS. 1 and 2, the brake device 20 includes a brake drum 21 fixed to the drive shaft 12 of the hoist 10, a pair of brake pads 22 that brake the rotation of the brake drum 21 by slidingly contacting the outer peripheral surface of the brake drum 21, a pair of brake arms 23 that support the brake pads 22 respectively and rotate to bring the brake pads 22 closer to the brake drum 21, and a pair of brake springs 24 that bias the brake arms 23 so that the brake pads 22 press the brake drum 21.

[0019] As shown in FIGS. 2 and 3, the brake device 20 supports a brake arm 23 biased by a brake spring 24 and includes a pair of adjustment bolts 25 that adjust the distance between the brake pad 22 and the brake drum 21 to a predetermined distance, and a pair of rotation levers 26 that are rotated by a brake plunger 27 described later to move each of the pair of adjustment bolts 25 in a direction in which the brake pad 22 separates from the brake drum 21 (outward in the width direction in FIG. 3).

[0020] The brake device 20 includes a brake plunger 27 that reciprocates in the front-rear direction by an electromagnetic force to rotate each of the pair of rotation levers 26, and a solenoid coil (not shown) that is configured to be insertable through the brake plunger 27 and to be energized or demagnetized to reciprocate the brake plunger 27 in the front-rear direction by an electromagnetic force.

[0021] In other words, the brake plunger 27 reciprocates in the front-rear direction by an electromagnetic force to move each of the pair of brake arms 23 in a direction in which the brake pad 22 separates from the brake drum 21 via the pair of rotation levers 26, thereby releasing the brake device 20.

[0022] The operation of the brake device 20 will be described. When the brake device 20 is braking, the brake arm 23 is biased by the brake spring 24, and the brake pad 22 presses the brake drum 21 so that the brake pad 22 is in sliding contact with the brake drum 21 to brake the rotation of the brake drum 21.

[0023] On the other hand, when the brake device 20 is released, the brake plunger 27 is moved forward in the front-rear direction by the solenoid coil. As a result, the rotation lever 26 rotates to move the adjustment bolt 25 outward in the width direction. At this time, the brake arm 23 opens in a direction in which the brake pad 22 separates from the brake drum 21 against the biasing force of the brake spring 24, and the braking of the brake drum 21 is released.

[0024] Using FIGS. 4 to 6, a brake switch mechanism 30 which is an example of the present embodiment will be described. FIG. 4 is a side view of the brake switch mechanism 30. FIG. 5 is a side view through the microswitch 40 in FIG. 4 for easy understanding of the description of the rotation operation piece 31. FIG. 6 is a cross-sectional view showing the inside of the microswitch 40.

[0025] A brake switch mechanism 30 which is an example of the present embodiment is provided in the brake device 20 of the hoist 10 of the elevator, and is a mechanism for detecting the braking or release of the brake device 20. According to the brake switch mechanism 30, although details will be described later, the operating point of the microswitch 40 described later can be easily confirmed while reducing the length (hereinafter referred to as stroke) of the reciprocating motion of the brake plunger 27 in the front-rear direction.

[0026] As shown in FIG. 4, the brake switch mechanism 30 is provided on the rear side in the front-rear direction of the hoist 10. The brake switch mechanism 30 includes a rotation operation piece 31 that rotates by the reciprocating motion of the brake plunger 27, a support beam 32 that rotatably supports the rotation operation piece 31, a tension spring 33 that biases the lower end portion of the rotation operation piece 31, a scale 34 for confirming the operation amount of the upper end portion of the rotation operation piece 31, and a microswitch 40 that opens and closes an electric circuit when a switch lever 42 described in detail later rotates.

[0027] The rotation operation piece 31 is an L-shaped flat plate and is rotatably supported at the rotation fulcrum M of the support beam 32. An engaging portion 31B protruding to the left side in the width direction (the front side of the paper surface in FIGS. 4 to 6) that engages with a roller 42A of a switch lever 42 described in detail later is provided at the upper end portion of the rotation operation piece 31. A through hole 31A is formed between the rotation fulcrum M of the rotation operation piece 31 and the engaging portion 31B, and the brake plunger 27 is inserted through this through hole 31A and is positioned at a predetermined position by a nut N. The lower end portion of the rotation operation piece 31 is biased in the clockwise direction by the tension spring 33, and the rotation operation piece 31 can follow the axial movement of the brake plunger 27.

[0028] The swing operation piece 31 is a member that swings by the reciprocating motion of the brake plunger 27 in the front-rear direction. According to the swing operation piece 31, the stroke of the brake plunger 27 can be enlarged and transmitted to the microswitch 40.

[0029] As described above, the brake plunger 27 penetrates through the through hole 31A. A screw portion is formed at the rear end portion of the brake plunger 27, and a nut N is screwed onto the screw portion. Thereby, when the brake plunger 27 moves forward when the brake device 20 is released, the nut N engages with the edge portion of the through hole 31A of the swing operation piece 31, and the upper end side of the swing operation piece 31 is pressed forward (counterclockwise in FIGS. 4 to 6), causing the swing operation piece 31 to swing.

[0030] The engaging portion 31B is formed to protrude from the swing operation piece 31 to the left side in the width direction (the front side of the paper surface in FIGS. 4 to 6), and the front surface of the engaging portion 31B abuts against the side peripheral surface of the roller 42A of the switch lever 42 described later. Thereby, when the brake plunger 27 moves forward when the brake device 20 is released and the upper end side of the swing operation piece 31 rotates forward (counterclockwise in FIGS. 4 to 6), the switch lever 42 of the microswitch 40 is pressed.

[0031] As described above, the support beam 32 is a member that rotatably supports the swing operation piece 31 at the rotation fulcrum M. The support beam 32 is provided so as to extend from the housing 35 of the brake device 20.

[0032] The tension spring 33 is a member that biases the lower end portion of the swing operation piece 31 to return to the front side when it is pulled to the rear side. The tension spring 33 is provided between the lower end portion of the swing operation piece 31 and the housing 35. Thereby, when the brake plunger 27 moves rearward during braking of the brake device 20, the swing operation piece 31 rotates clockwise following the brake plunger 27.

[0033] The scale 34 allows an operator to visually confirm the operating amount of the upper end portion (engagement portion 31B) of the rotation operation piece 31. According to the scale 34, for example, the intermediate point in the stroke of the rotation operation piece 31 can be easily confirmed. The scale 34 is provided on the side surface of the housing 41 of the microswitch 40, which will be described in detail later.

[0034] As described above, the microswitch 40 is a switch that opens and closes an electric circuit connected to, for example, a control device of an elevator when the switch lever 42 rotates. According to the microswitch 40, a mechanical operation of the rotation of the rotation operation piece 31 can be converted into an electric signal of opening and closing an electric circuit. The microswitch 40 of the present embodiment uses a hinge-roller type microswitch, but is not limited thereto.

[0035] As shown in FIGS. 4 and 6, the microswitch 40 includes a housing 41 having a sealed internal space, a switch lever 42 that rotates by the rotation of the rotation operation piece 31, a slider 43 that is pressed by the rotation of the switch lever 42, and a conductive movable piece 44 that abuts on, for example, a normally open terminal 45A when pressed by the slider 43.

[0036] The housing 41 is supported by a support base 46 and fixed to the housing 35 of the brake device 20. The housing 41 houses a conductive movable piece 44, a normally open terminal 45A, and a normally closed terminal 45B in its sealed internal space.

[0037] The switch lever 42 is a lever that is pressed by the rotation of the rotation operation piece 31 and rotates to press the slider 43. The base end portion 42B of the switch lever 42 is rotatably supported at the lower end portion of the rear side surface of the housing 41, and a roller 42A is supported at the free end portion. The switch lever 42 is always biased rearward from the housing 41 by the slider 43.

[0038] The slider 43 moves forward in the housing 41 by being pressed by the switch lever 42 and presses the conductive movable piece 44. The slider 43 is biased backward from the housing 41 by the conductive movable piece 44.

[0039] The conductive movable piece 44 is a member that contacts, for example, the normally open terminal 45A when pressed by the slider 43. The base end portion of the conductive movable piece 44 is rotatably supported, and the tip end portion contacts or separates from the normally open terminal 45A by rotating. The conductive movable piece 44 is always biased by the spring member 44A in a direction to contact the normally closed terminal 45B.

[0040] The base end portion of the conductive movable piece 44, the normally open terminal 45A, and the normally closed terminal 45B are each electrically connected to an external terminal to form an electric circuit. For example, when an electric circuit is formed between the base end portion of the conductive movable piece 44 and the normally open terminal 45A, the microswitch 40 functions as an open contact. Also, when an electric circuit is formed between the base end portion of the conductive movable piece 44 and the normally closed terminal 45B, the microswitch 40 functions as a closed contact. Furthermore, when an electric circuit is formed between the base end portion of the conductive movable piece 44, the normally open terminal 45A, and the normally closed terminal 45B, the microswitch 40 functions as a changeover contact.

[0041] The operation of the microswitch 40 will be described. In the microswitch 40, the conductive movable piece 44 is always biased by the spring member 44A in a direction to contact the normally closed terminal 45B. As a result, the slider 43 is biased backward by the conductive movable piece 44, and the switch lever 42 is biased backward from the housing 41 by the slider 43.

[0042] In the microswitch 40, when the brake device 20 is released, the brake plunger 27 moves forward, and the switch lever 42 is pressed and rotated by the rotation of the rotation operation piece 31. As a result, the slider 43 is pressed forward by the switch lever 42, the conductive movable piece 44 is pressed forward and contacts the normally open terminal 45A, and the electric circuit connected to the microswitch 40 is opened.

[0043] With reference to FIG. 7, the operation of the brake switch mechanism 30 will be described. FIG. 7(A) is a diagram showing the brake switch mechanism 30 when the braking device 20 is braking. FIG. 7(B) is a diagram showing the brake switch mechanism 30 when the braking device 20 is released.

[0044] As shown in FIG. 7(A), when the braking device 20 is braking, the brake plunger 27 is located at the rear side. In the brake switch mechanism 30, the lower end of the rotation operation piece 31 is biased forward by the biasing force of the tension spring 33, the rotation operation piece 31 is inclined in the clockwise direction, and is in contact with the nut N screwed onto the brake plunger 27.

[0045] As shown in FIG. 7(B), when the braking device 20 is released, the brake plunger 27 moves forward. In the brake switch mechanism 30, the rotation operation piece 31 is pressed forward by the nut N screwed onto the brake plunger 27 and is inclined in the counterclockwise direction. At this time, the engaging portion 31B of the rotation operation piece 31 presses the switch lever 42 of the microswitch 40, thereby switching the electric circuit connected to the microswitch 40.

[0046] An example of the maintenance inspection work of the braking device 20 provided with the brake switch mechanism 30 will be described.

[0047] First, a buzzer or a lamp is connected in parallel to the external terminals of the microswitch 40 of the brake switch mechanism 30 so that the timing of the operating point (open or closed) of the microswitch 40 can be confirmed from the outside. Next, the rotation operation piece 31 is manually rotated, and the position of the upper end of the rotation operation piece 31 at the timing of the operating point of the microswitch 40 is confirmed by the scale 34. At this time, since the stroke of the brake plunger 27 is enlarged by the rotation operation piece 31, the operator can easily confirm the operating point of the microswitch 40 within the range of the stroke of the brake plunger 27.

[0048] Next, actually operate the braking device 20, and as the range of the stroke of the brake plunger 27 when the braking device 20 is braked or released, confirm the operating range of the upper end of the rotation operation piece 31 with the scale 34. At this time, since the magnitude of the stroke of the brake plunger 27 is enlarged by the rotation operation piece 31, the operator can easily confirm the stroke of the brake plunger 27.

[0049] And if the position of the upper end of the rotation operation piece 31 at the operating point of the microswitch 40 is near the middle of the operating range of the upper end (engagement portion 31B) of the rotation operation piece 31 when the braking device 20 is braked or released, it can be said that the brake switch mechanism 30 is in an appropriate state. On the other hand, when the position of the upper end of the rotation operation piece 31 at the timing of the operating point of the microswitch 40 is near both ends of the operating range of the upper end of the rotation operation piece 31 when the braking device 20 is braked or released, adjustments such as correcting the stroke of the brake plunger 27 or correcting the position of the microswitch 40 are performed.

[0050] Note that the present invention is not limited to the above-described embodiments and their modifications, and it goes without saying that various changes and improvements can be made within the scope of the matters described in the claims of the present application.

Explanation of Reference Numerals

[0051] 10 Hoisting machine, 11 Rope pulley, 12 Driving shaft, 13 Electric motor, 15 Casing, 20 Braking device, 21 Brake drum, 22 Brake pad, 23 Brake arm, 24 Brake spring, 25 Adjusting bolt, 26 Rotating lever, 27 Brake plunger, 30 Brake switch mechanism, 31 Rotation operation piece, 31A Through hole, 31B Engagement portion, 32 Support beam, 33 Tension spring, 34 Scale, 35 Housing, 40 Microswitch, 41 Housing, 42 Switch lever, 42A Roller, 43 Slider, 44 Conductive movable piece, 44A Spring member, 45A Normally open terminal, 45B Normally closed terminal, 46 Support base

Claims

1. An elevator brake switch mechanism is provided in a brake device of an elevator hoisting machine and detects braking or release of the brake device, The brake device includes a brake drum fixed to a drive shaft of the hoist, a brake pad capable of slidingly contacting an outer peripheral surface of the brake drum, an arm supporting the brake pad and biased by a spring to press the brake pad against the brake drum, and a brake plunger that moves back and forth by electromagnetic force to move the arm via a rotating lever in a direction in which the brake pad moves away from the brake drum, a rotating operation piece having a pivot point that is pivotally supported on a support beam that is fixed to the hoist, the rotating operation piece being L-shaped and engaging with the brake plunger between the pivot point and a tip end, the portion from the pivot point to the tip end forming one side of the L shape, the tip end forming the other side of the L shape, and the tip end being rotated by the reciprocating motion of the brake plunger; a switch lever rotatably supported on a microswitch housing, engaging with the tip of the rotary operation piece and rotating as the rotary operation piece rotates, a slider provided on the microswitch housing and pressed by the rotation of the switch lever, and a conductive movable piece disposed inside the microswitch housing and pressed by the slider to come into contact with or separate from a terminal, the microswitch opening and closing an electric circuit connected as the switch lever rotates; Equipped with Elevator brake switch mechanism.

2. 2. The elevator brake switch mechanism according to claim 1, Further, a scale is provided for checking the amount of movement of the tip of the rotating operation piece. Elevator brake switch mechanism.

Images