JP2777270B2 - Hoisting machine brake release device - Google Patents

Description

The present invention relates to a brake release device that releases a brake mechanism incorporated in, for example, an elevator hoist.

(Prior Art) A brake mechanism incorporated in a hoist of this type, which has been already proposed, and a brake release device for releasing the brake mechanism are configured as shown in FIGS. 7 to 10. I have.

That is, a pair of brackets 2a, 2a are attached to the machine frame 2 beside the brake drum 1 of the elevator hoist so as to face each other with the brake drum 1 interposed therebetween. The bases of the pair of brake arms 3, 3 are pivotally supported on the brackets 2a, 2a by support shafts 4, 4, respectively. Also, brake arm 3,
In the middle of 3, brake shoes 5, 5 are mounted via pins 6, 6, respectively. Thus, the brake shoes 3, 5 can be pressed against or separated from the outer peripheral surface of the brake drum 1 by swinging the brake arms 3, 3 so as to come into contact with and separate from the brake drum.

On the other hand, above the brake drum 1 is provided a machine frame 8 containing an electromagnet 7 composed of a plunger 7a and a coil 7b. A pair of ear pieces provided on the machine casing 8
A pair of brake springs 9, 9 for pressing the brake shoes 5, 5 against the brake drum 1 are connected to the 8a, 8a via supporting rods 10, 10 so as to be freely adjustable in length. Further, a pair of release levers 11, 11 for separating the brake shoes 5, 5 from the brake drum are provided on the ear pieces 8a, 8b, and a pair of pin shafts 12, 12 are provided.
And is rotatably supported via.

One end of each of the release levers 11 is connected to a plunger 7a.
Is in contact with the lower end of the The other ends of the release levers 11, 11 are in contact with the tips of a pair of adjustment screw rods 13, 13 screwed to the brake arms 3, 3, respectively. Accordingly, when the plunger 7a is displaced downward, the pair of release levers 11, 11 are respectively rotated around the pin shafts 12, 12, and the brake arms 3, 3 are adjusted via the adjustment screw rods 13, 13. Since the rockers are swung, the brake shoes 5, 5 can be separated from the brake drum 1.

The bracket 14 attached to the upper part of the machine frame 8 includes
An operation lever 15 is swingably supported via a support shaft 16. A pressing portion 15a formed in an arc shape is formed in a portion of the operation lever 15 located immediately above the plunger 7a. As a result, when the operator pushes the tip of the operation lever 15 downward in the figure during maintenance and inspection work, the plunger
7a is displaced downward, so that the brake shoes 5, 5 are separated from the brake drum 1 via the release levers 11, 11, the adjustment screw rods 13, 13, and the brake arms 3, 3, and the brake mechanism is released. The hoist can be maintained and inspected.

The above-described brake mechanism incorporated in the hoist energizes the coil 7b of the electromagnet 7 during normal operation, and
7a is displaced downward in the figure. Then, as described above, the brake shoes 5, 5 are separated from the brake drum 1, and the brake mechanism is released. On the other hand, the power supply to the electromagnet 7 is cut off during normal braking or when the brake power is turned off due to a power failure or some other cause. Then, since the plunger 7a cannot rotate the release levers 11,11, the brake shoes 5,5 are pressed by the brake drum 1 by the spring force of the brake springs 9,9 to brake the brake drum 1.

(Problems to be Solved by the Invention) As described above, when the operation lever 15 of the brake release device is operated to swing around the support shaft 16, the pressing portion 15a of the operation lever 15 presses the plunger 7a. Displace. At this time, with the downward displacement of the plunger 7a, the relative angle between the operation lever 15 and the plunger 7a changes.

However, since the support shaft 16 that supports the operation lever 15 is fixed so as not to be displaceable relative to the machine frame 8, the operation lever
In the case of 15, the pressing portion 15a must rotate relative to the plunger 7a while swinging on the surface of the plunger 7a.

As a result, in the conventional brake release device described above, friction occurs between the pressing portion 15a of the operation lever 15 and the plunger 7a. The friction increases as the pressing force of the pressing portion 15a pressing the plunger 7a increases.

When the friction between the pressing portion 15a and the plunger 7a increases, the lever ratio of the operation lever 15 must be increased in order to suppress the operation force for operating the operation lever 15 within a certain range. The overall length of the lever 15 becomes longer, and the brake release device becomes larger.

Further, the sliding between the pressing portion 15a and the plunger 7a causes the first
As shown in FIG. 0, since the upper surface of the plunger 7a is worn to form the dent 7c, not only the frictional resistance is further increased, but also the pressing portion 15a is caught by the dent 7c.
Unless a force in the reverse direction is applied to 5, the plunger 7a cannot be restored to the original position.

That is, in the conventional brake release device described above, the operation of the operation lever 15 causes the brake shoes 5, 5
Cannot be easily and smoothly pressed against or separated from the brake drum 1 by the operation of the operation lever 15, which makes it difficult to attach the elevator car to the nearest floor by operating the operation lever 15. There is a problem that the workability is poor.

Therefore, the present invention has been made in view of the above-described circumstances, and the pressing portion 15a of the operation lever 15 and the plunger 7a
To provide a brake release device for a hoisting machine that can easily and smoothly operate the operation lever 15 by reducing a frictional force between the hoisting machine and the vehicle. With the goal.

[Configuration of the invention]

(Means for Solving the Problems) In order to solve the above problems, a brake release device for a hoist according to the present invention includes a brake mechanism for pressing or separating a brake shoe on a brake drum of the hoist; A displacement member that is reciprocally displaceably supported by the machine frame of the upper machine, and that is displaced in one direction, activates the brake mechanism to separate the brake shoe from the brake drum, and a swing link. A support member swingably supported by the machine frame, and a base end rotatably supported by the support member and capable of pressing the displacement member on the base end side in the one direction. And an operation lever for displacing the displacement member in the one direction by pushing a tip thereof.

The swing link supports the support member so as to be swingable with respect to the machine frame in a longitudinal direction of the operation lever.

(Operation) That is, when the tip of the operation lever is pushed to swing around the support shaft, the pressing portion of the operation lever pushes the plunger to displace it. At this time, with the displacement of the plunger,
The relative angle between the operating lever and the plunger must change.

In this case, in the brake release mechanism of the present invention, the support member that supports the operation lever is supported by the swing link and is swingable in the longitudinal direction of the operation lever with respect to the machine frame. Can be displaced in the longitudinal direction of the operation lever.

Accordingly, the operation lever can be displaced so as to approach the contact point between the pressing portion and the plunger while rotating relative to the plunger using the contact point between the pressing portion and the plunger as a fulcrum.

Therefore, unlike the conventional brake release mechanism in which the support shaft of the operation lever is fixed to the machine frame so as not to be displaceable, in the brake release device according to the present invention, the pressing portion of the operation lever slides on the surface of the plunger. There is no significant friction or wear between them,
The operation lever can be easily operated.

(Embodiment) Hereinafter, a brake release device for a hoist according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 7.

Here, FIG. 1 is an enlarged fragmentary front view showing a main part of the brake release device according to the present invention, FIG. 2 is a side view of the brake release device shown in FIG. 1, and FIG. FIGS. 4 and 5 are enlarged front views of essential parts for explaining the operation of the brake release device according to the present invention, and FIG. 6 is an enlarged front view of the brake release device according to the present invention. It is a principal part enlarged front view which shows another Example.

In the following description, the same parts as those in the above-described conventional example will be denoted by the same reference numerals.

First, a brake mechanism of a hoist to which the brake release device of the present embodiment is applied will be described with reference to FIGS.

As shown in FIG. 7, a pair of brackets 2a, 2 is provided on a machine frame 2 beside a brake drum 1 of an elevator hoist.
a are provided so as to face each other with the brake drum 1 interposed therebetween. And these brackets 2a, 2
In a, the bases of a pair of brake arms 3, 3 are pivotally supported by pivots 4, 4, respectively. In the middle of the brake arms 3, 3, brake shoes 5, 5 are mounted via pins 6, 6, respectively. Thus, the brake shoes 3, 5 can be pressed against or separated from the outer peripheral surface of the brake drum 1 by swinging the brake arms 3, 3 so as to come into contact with and separate from the brake drum.

On the other hand, above the brake drum 1 is provided a machine frame 8 containing an electromagnet 7 composed of a plunger 7a and a coil 7b. A pair of ear pieces provided on the machine casing 8
A pair of brake springs 9, 9 for pressing the brake shoes 5, 5 against the brake drum 1 are connected to the 8a, 8a via supporting rods 10, 10 so as to be freely adjustable in length. Further, a pair of release levers 11,11 for separating the brake shoes 5,5 from the brake drum are provided on the ear pieces 8a, 8a, and a pair of pin shafts 12,12.
And is rotatably supported via.

One ends of these release levers 11, 11 are in contact with the lower end of the plunger 7a. The other ends of the release levers 11, 11 are in contact with the tips of a pair of adjusting screw rods 13, 13 screwed to the brake arms 3, 3, respectively. Accordingly, when the plunger 7a is displaced downward, the pair of release levers 11, 11 are respectively rotated around the pin shafts 12, 12, and the brake arms 3, 3 are adjusted via the adjustment screw rods 13, 13. The brake shoes 5 are separated from the brake drum 1 by swinging.

In the normal operation, the above-described brake mechanism energizes the coil 7b of the electromagnet 7 to displace the plunger 7a downward in the drawing. Then, as described above, the brake shoes 5,5
Is separated from the brake drum 1, so that the brake mechanism is released. On the other hand, the power supply to the electromagnet 7 is cut off during normal braking or when the brake power is turned off due to a power failure or some other cause. Then, since the plunger 7a cannot rotate the release levers 11, 11, the brake shoes 5, 5 are pressed against the brake drum 1 by the spring force of the brake springs 9, 9, and the brake drum 1
Brake.

Next, the brake release mechanism of the present embodiment will be described with reference to FIGS.

As shown in FIG. 1, the lugs 8a, 8a of the machine frame 8 of the hoisting machine.
The lower ends of the pair of swing links 22 and 22 are
They are pivotally supported by 1b and 21b, respectively. The upper ends of the swing links 22 and 22 are provided with electromagnets 7.
Both ends of a strip-shaped support member 20 arranged so as to straddle are pivotally supported by a pair of pins 21a, 21a, respectively. Thus, the support member 20 can freely swing in the horizontal direction in the figure with respect to the machine frame 8.

As shown in FIGS. 2 and 3, an auxiliary plate 20a extending parallel to the support member 20 is provided on the support member 20 with a predetermined distance from the support member 20 via a pair of separating pieces 20b. It is installed so as to open the gap. Also, a support member
A base end 23a of an operation lever 23 extending in the same direction as the swinging direction of the support member 20 is inserted into a gap between the support plate 20a and the support plate 20a. The operation lever 23 has a base end 23a.
Are rotatably supported by the support member 20 via the support shaft 24, and are rotatably supported by the support member 20.

From the base end 23a of the operation lever 23, an arc-shaped pressing portion 23b swells downward and rolls against the upper surface of the plunger 7a. Thus, when the operator pushes down the tip of the operation lever 23, the pressing portion 23b of the operation lever 23 pushes down the plunger 7a.

Next, the operation of the brake release device configured as described above will be described.

At the time of maintenance and inspection work, it is necessary to release the above-mentioned brake mechanism by manual operation and attach the elevator car to the nearest floor. Therefore, the operator pushes the tip of the operation lever 23 downward in the figure to forcibly displace the plunger 7a downward.

At this time, with the displacement of the plunger 7a, the operation lever
The relative angle between 23 and plunger 7a must change.

In this case, in the brake release mechanism of the present embodiment,
Since the support member 20 supporting the operation lever 23 is supported by the swing link 22 and is swingable in the longitudinal direction of the operation lever 23 with respect to the machine frame 8, the support shaft supporting the operation lever 23 is provided. 24 can be displaced in the longitudinal direction of the operation lever 23.

Accordingly, the operation lever 23 rotates relative to the plunger 7a with the contact point between the pressing portion 23b and the plunger 7a as a fulcrum, and the support shaft 24 moves the pressing portion 23b and the plunger 7a.
Can be displaced in the longitudinal direction of the operation lever 23 so as to approach the contact point.

Therefore, unlike the conventional brake release mechanism in which the support shaft of the operation lever is fixed so as not to be displaceable with respect to the machine frame, in the brake release device of the present embodiment, the pressing portion 23b of the operation lever 23 has the surface of the plunger 7a. Since the upper lever does not slide, the operation lever 23 can be easily operated.

Further, since the pressing portion 23b of the operation lever 23 is formed to bulge in an arc shape, when the operator pushes the tip of the operation lever 23 to displace the plunger 7a, the operation lever 23 The pressing portion 23b rolls smoothly on the surface of the plunger 7a.

Therefore, according to the brake release device of the present embodiment,
Since no large friction occurs between the pressing portion 23b of the operating lever 23 and the surface of the plunger 7a, not only can the operating lever 23 be easily operated, but also the pressing portion 23b of the operating lever 23 can be provided on the surface of the plunger 7a. There is no abrasion caused by sliding with the sliding member.

This makes it possible to easily operate the operation lever 23 to release the brake mechanism when performing maintenance and inspection of the elevator hoist, thereby facilitating the work of attaching the elevator car to the nearest floor. It can be carried out.

Next, a brake release device according to another embodiment will be described with reference to FIG. 6. A pair of swing links 22, 22 shown in FIG.
At the lower end of the shaft, there are formed engagement grooves 22a, 22a capable of engaging with and disengaging from the pin shafts 21b, 21b.

Thereby, the pair of swing links 22, 22 are connected to the pin shafts 21b, 21b.
By removing the support member 20 and the operation lever 23 from the machine frame 8, the maintenance work of the hoisting machine of the elevator can be more easily performed.

〔The invention's effect〕

As is apparent from the above description, the brake release device for a hoist according to the present invention includes an operating lever that presses a plunger for separating a brake shoe from a brake drum with respect to a machine frame of the hoist. The operating lever is pivotally supported by a support member that is swingably supported in the longitudinal direction of the operating lever, and the operating lever rotates relative to the plunger with a contact point between the pressing portion and the plunger as a fulcrum, while the supporting shaft is in contact with the pressing portion. It can be displaced closer to the point of contact with the plunger.

Therefore, since the pressing portion of the operation lever does not slide on the surface of the plunger, friction and wear do not occur between the two, and the operation lever can be easily operated.

[Brief description of the drawings]

FIG. 1 is an enlarged fragmentary front view showing a main part of a brake release device according to the present invention, FIG. 2 is a side view of the brake release device shown in FIG. 1, and FIG. FIGS. 4 and 5 are enlarged front views of essential parts for explaining the operation of the brake release device according to the present invention, and FIG. 6 is another embodiment of the brake release device according to the present invention. FIG. 7 is an overall front view of a brake release device already proposed, FIG. 8 is a cross-sectional view showing an enlarged main portion of the brake release device shown in FIG. 9
FIG. 10 and FIG. 10 are enlarged front views of essential parts for explaining the operation of the brake release device shown in FIG. 1 ... Brake drum, 3 ... Brake arm, 5 ...
Brake shoe, 7a ... Plunger, 8 ... Machine frame, 9 ...
... Brake spring, 11 ... Release lever, 13 ... Adjustment screw rod, 20 ... Support member, 22 ... Swing link, 23 ... Operation lever, 23b ... Pressing portion.

Claims (1)

(57) [Claims] A brake mechanism for pressing or separating a brake shoe against a brake drum of the hoist; and a reciprocally displaceable support on the machine frame of the hoist; A displacement member that operates a brake mechanism to separate the brake shoe from the brake drum; a support member that is swingably supported by the machine frame via a swing link; and a base end pivotally moved by the support member. While being freely supported,
An operation lever for displacing the displacement member in the one direction by pressing the distal end of the displacement member on the base end side, the pressing portion being capable of pressing the displacement member in the one direction, A brake release device for a hoist, wherein the swing link supports the support member so as to be swingable with respect to the machine frame in a longitudinal direction of the operation lever.