JP3062470U - Wire drum for electric hoist - Google Patents

Abstract

(57) [Summary] In an operation using an electric hoist, a hoisting speed is varied according to an actual cargo handling operation, safety during the operation is improved, and the life of the electric hoist is extended. SOLUTION: A wire drum 9 for winding or unwinding a winding wire rope 5 on a peripheral surface, the large diameter circumferential surface W1 to which a winding start end of the winding wire rope 5 is assigned, and the same winding wire. A cross-section for continuously connecting the small-diameter peripheral surface W3 to which the winding end of the rope 5 is assigned by a tapered peripheral surface W2, and guiding the winding wire rope 5 to each of the peripheral surfaces W1, W2, W3. A substantially V-shaped threaded groove 10 is formed, and the substantially V-shaped shape is such that the hoisting wire rope 5 does not adhere to the groove bottom when no load is applied, and the hoisting wire rope 5 is It has a cross-sectional shape that makes contact with the bottom.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to an improvement in a wire drum of an electric hoist (hereinafter, abbreviated as a hoist) in which a hoisting wire rope is sequentially wound in a lateral direction to lift a load.

[0002]

[Prior art]

 An example of a conventional hoist for sequentially winding up a hoisting wire rope and lifting a load will be described with reference to FIG. 3 (a perspective view showing the configuration). The drive mechanism of the hoist includes a hoisting motor 1 composed of a three-phase squirrel-cage induction motor, a speed reducer 2 that reduces the rotational force of the hoisting motor 1, and a rotating mechanism that receives the rotational force reduced by the reducer 2 to rotate. And a magnet brake 4 for braking the hoisting motor 1.

[0003] One end 5a of a hoisting wire rope 5 is fixed to the wire drum 3, and the other end 5b of the hoisting wire rope 5 is fixed to a drum case 7 via a hook block 6, and The load is lifted and lowered by the rotational force from the drive mechanism.

Usually, in order to reduce the pulling force applied to one end 5a of the hoisting wire rope 5 during lifting and lowering of a load, two or more turns of the wire drum 3 are wound on the wire drum 3 in a state in which the hook block 6 is lowered to a specified head. The winding wire rope 5 is left, and a portion where a winding effect is obtained by the frictional force between the wire drum 3 and the winding wire rope 5, that is, a “side winding” is secured.

[0005] The shape of such a conventional wire drum 3 is generally cylindrical. At the winding start end (rear side of the wire drum in FIG. 3) and the winding end end (front side of the wire drum in FIG. 3) of the winding wire rope 5, the diameter D of the pitch circle of the wire drum 3 (to the wire drum 3). The diameter of the wire drum 3 from the substantially axial center to the substantially axial center of the hoisting wire rope 5 in a state where the hoisting wire rope 5 is wound (see FIG. 4) is the same diameter.

[0006] Flanges 3a, 3a are formed on both sides of the wire drum 3, and a threaded groove 8 (hereinafter referred to as a guide) for guiding the winding of the winding wire rope 5 is formed on the peripheral surface of the wire drum 3. The winding wire rope 5 is wound around the screw groove 8 in a single layer.

As shown in FIG. 4, the thread groove 8 provided on the peripheral surface of the wire drum 3 has a pitch p larger than the diameter d of the winding wire rope 5 so that the winding wire ropes 5 do not contact each other. The height c is made slightly larger, the height c is about 1/3 of the diameter d of the winding wire rope 5, and the groove bottom radius R is made slightly larger than the radius r of the winding wire rope 5.

The hoisting speed of the conventional hoist configured as described above is usually a constant speed if the rotating speed of the hoisting motor 1 is constant, since the wire drum 3 is cylindrical. Therefore, in order to vary the hoist hoisting speed, it was necessary to vary the number of revolutions of the hoisting motor 1. For example, by changing the number of poles by adopting a pole conversion type motor for the hoisting motor 1 or changing the power frequency by using an inverter, the rotation speed of the hoisting motor 1 can be varied. The winding speed was variable.

[0009]

[Problems to be solved by the invention]

 With a conventional general hoist, the hoisting speed is constant regardless of whether or not there is a load. There is a problem that work efficiency is reduced due to occurrence of the problem. In addition, hoists with variable hoisting speeds had a problem in that the cost was increased because a pole conversion motor was used as a hoisting motor or a separate inverter was required.

[0010] It is desirable from the viewpoint of safety that the frictional force with respect to the wire drum in the winding portion of the hoisting wire rope is increased and the tensile force applied to the end of the hoisting wire rope is reduced. Also, when lifting a load, it is required not to lift the load abruptly in order to reduce the impact, especially when the load is lifted off the ground (in the case of lifting off the ground). They are often chased and suddenly cut off. In this case, the impact at the time of ground cutting is a heavy burden on each component of the hoisting wire rope, slinging wire rope, and hoist, which impairs safety and shortens the service life of the hoist. . Nevertheless, conventional hoists did not take structural considerations in this regard to ensure safety or extend the life of the hoist.

Therefore, in order to solve the above-mentioned conventional problems, it is possible to easily change the hoisting speed according to the actual cargo handling work, to reduce unnecessary waiting time of the cargo handling worker, and to improve the working efficiency. The purpose of this study was to provide a hoist wire drum aiming to improve the safety during work and extend the life of the hoist.

[0012]

[Means for Solving the Problems]

 First, in order to improve work efficiency, a wire drum for winding or unwinding a hoisting wire rope on the circumferential surface is the same as a large-diameter circumferential surface to which the winding start end of the hoisting wire rope is assigned. A wire drum was formed by continuously connecting a small diameter peripheral surface to which the winding end of the hoisting wire rope was assigned by a tapered peripheral surface. This wire drum changes the winding speed by changing the winding radius. The large-diameter peripheral surface and the small-diameter peripheral surface may have a constant width, or a large-diameter peripheral surface and a small-diameter peripheral surface may be assigned to both edges of the peripheral surface, and the entire peripheral surface may be a substantially continuous tapered peripheral surface.

[0013] The wire drum of the present invention has a winding start end assigned to a large-diameter peripheral surface and a winding end end assigned to a small-diameter peripheral surface. The upper wire rope is wound up at a high speed, then moved to the taper part of the wire drum in sequence, and by the time of transition to steady operation after ground cutting, the circumference of the small diameter or at least the taper circumference with a smaller winding radius than the circumference of the large diameter. Wind up at low speed on the surface. Conversely, at the time of unwinding, the hoisting wire rope is wound down at a lower speed than the small diameter peripheral surface of the wire drum. Then, the hoisting wire rope moves to the tapered peripheral surface of the wire drum in sequence, and when the suspended load touches the ground and the slinging wire rope is relaxed, the hoisting wire rope has a high speed due to the large diameter peripheral surface. To wind down.

Next, in order to enhance safety, a thread groove having a substantially V-shaped cross section for guiding a wire rope for winding is formed on the peripheral surface of the wire drum. The wire drum had a cross-sectional shape such that the hoisting wire rope did not adhere to the groove bottom when there was no load, and the hoisting wire rope was in contact with the groove bottom when loading. As a result, when a load is applied to the hoisting wire rope, the hoisting wire rope slightly deforms the wire cross section so as to bite into the V-shaped thread groove, and the deformation causes an impact load at the time of ground cutting. Absorb.

[0015]

[Embodiment of the invention]

 Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a partially cutaway perspective view of a wire drum showing an example of the present invention, and FIG. 2 is a sectional view of a thread groove provided on a peripheral surface of the wire drum. The wire drum 9 of the present embodiment is made of a casting, and as shown in FIG. 1, a drum main body 9a is formed at a central portion where the winding wire rope 5 is wound. The flange portions 9b, 9b are formed to prevent the falling off of the flange.

The wire drum 9 has support walls 9c, 9c provided in a drum main body 9a, and bosses 9d, 9d serving as drum support pieces are formed at the edges of each support wall 9c. In the wire drum 9, the bosses 9d are supported by a bracket (not shown) of the hoisting motor 1 and a bracket (not shown) of the speed reducer 2 via bearings (not shown), respectively. It is rotatably supported as a whole.

As shown in FIG. 1, the drum main body 9 a divides the peripheral surface of the wire drum 9 into approximately one-third by the winding width of the hoisting wire rope 5, and The winding diameter of the peripheral surface W1 to which the winding start end is assigned (left side in FIG. 1) and the peripheral surface W3 to which the winding end end is assigned (right side in FIG. 1) are made different. That is, the circumferential surface of the wire drum 9 at the winding start end of the winding wire rope 5 is defined as a large-diameter circumferential surface W1 having a pitch circle diameter D1, and the wire drum at the winding end end of the winding wire rope 5 is formed. 9 is a small-diameter peripheral surface W3 having a diameter D2 of the pitch circle. The transition from the large-diameter peripheral surface W1 to the small-diameter peripheral surface W3 is a tapered peripheral surface W2. In the present embodiment, about one-third of the winding width of the wire drum is assigned to the large-diameter peripheral surface, the tapered peripheral surface, and the small-diameter peripheral surface, respectively. A small diameter peripheral surface may be allocated, and the entire peripheral surface may be a substantially continuous tapered peripheral surface.

When the hoist is used as a hoist of a crane, the diameter D of the pitch circle of the wire drum 9 (in the range of D1 to D2 in this example) and the wire rope 5 for winding wound on the wire drum 9 are used. The minimum value of the ratio to the diameter d (D / d) is specified in the crane structural standard. Therefore, in the wire drum 9 of the present invention, the diameter D2 of the pitch circle at the winding end of the winding wire rope 5 is determined so as to satisfy the specified value.

Next, the thread groove 10 provided on the peripheral surface of the wire drum 9 for winding the wire rope 5 for winding will be described with reference to FIG. The shape of the screw groove 10 is substantially V-shaped as shown in FIG. 2, and the screw groove 10 having the same cross-sectional shape is formed on the entire peripheral surface of the drum main body 9a. The hoisting wire rope 5 is wound around the thread groove 10. The cross-sectional shape of the thread groove 10 is a substantially V-shape having a groove bottom radius R slightly smaller than the radius r of the hoisting wire rope 5 and having a wall surface which falls straight toward the groove bottom 10b. For this reason, when no load is applied, the hoisting wire rope 5 keeps a gap g between itself and the groove bottom 10b while being wound up by the thread groove 10 of the wire drum 9. Then, under load, the winding wire rope 5 slightly deforms its cross-sectional shape toward the groove bottom 10b so as to eliminate the gap g, and comes into contact with the groove bottom 10b. This slight deformation of the hoisting wire rope 5 absorbs the impact at the time of ground cutting. In order to better realize the shock absorption due to the deformation of the hoisting wire rope 5, the pitch p 'of the thread groove 10 is slightly larger than the diameter d of the hoisting wire rope 5, and the height of the thread groove 10 is increased. c ′ is made slightly smaller than the diameter d of the hoisting wire rope 5.

The hoisting or hoisting of the hoisting wire rope 5 in the hoist configured as described above is as follows. One end 5a (see FIG. 3) of the hoisting wire rope 5 is fixed to the starting end of the wire drum 9, which is the large-diameter peripheral surface W1. After the winding wire rope 5 is wound around the thread groove 10 (two turns) on the circumferential surface W4 of the all-winding portion, the thread groove 10 on the large-diameter circumferential surface W1, the screw groove 10 on the tapered circumferential surface W2, Then, it is sequentially wound around the thread groove 10 of the small diameter peripheral surface W3. Therefore, if the wire drum 9 is rotated by the driving force from the hoisting motor 1 (see FIG. 3) of the hoisting drive mechanism, the hoisting wire rope 5 is sequentially wound in the X direction in FIG. It is being done. In the use as a crane, as shown in FIG. 3, a hook block 6 is further attached in the middle of the hoisting wire rope 5, and the end of the hoisting wire rope 5 is fixed to the drum case 7.

At the time of hoisting, that is, in an empty load operation until the sling wire rope is tensioned, the hoisting wire rope 5 is wound on the large-diameter peripheral surface W 1 of the wire drum 9 and wound at high speed. In other words, if the rotation speed of the rotating shaft of the hoisting motor 1 is constant, the peripheral speed increases as the diameter of the peripheral surface increases, so that the winding is performed at a high speed. Then, the hoisting wire rope 5 is subsequently moved to the tapered peripheral surface W2 and wound up, and in the stage of steady operation after the ground cutting, the hoisting wire rope 5 is wound up on the small diameter peripheral surface W3. It can be wound at low speed.

In addition, in the helical winding portion of the hoisting wire rope 5 fixed to the wire drum 9, when a load is applied to the hoisting wire rope 5, the hoisting wire rope 5 bites into the thread groove 10. As a result, the frictional force between the wire drum 9 and the hoisting wire rope 5 is increased, and the propagation of the load to one end 5a of the hoisting wire rope 5 due to the load pulling the hoisting wire rope 5 is suppressed. I do. Furthermore, the hoisting wire rope 5 wound up in the V-shaped thread groove 10 is wound “shallowly” to the extent that the gap g is ensured during the empty load operation, but the groove bottom 10b during the load operation. The hoisting wire rope 5 comes into contact with the wire rope 9 and the hoisting wire rope 5 is sequentially wound on the wire drum 9 while absorbing the load by slightly deforming the hoisting wire rope 5.

[0023]

[Effect of the invention]

 The present invention is configured as described above in detail, and thus has the following effects. The combination of the large-diameter peripheral surface, small-diameter peripheral surface and tapered peripheral surface makes it possible to easily change the hoisting speed according to the actual cargo handling operation. This allows the hoisting wire rope to be wound up or down at a high speed during empty loading until the slinging wire rope is tensioned or relaxed, thereby reducing the waiting time of the cargo handling worker and increasing the work efficiency. Also, after the ground cut, the hoisting wire rope can be hoisted or lowered at a low speed to reduce the lifting speed of the load, thereby improving safety.

The thread groove having a substantially V-shaped cross-section formed on the peripheral surface of the wire drum slightly deforms the cross-sectional shape of the winding wire rope when a load is applied, and forms a gap g that abuts on the groove bottom. This makes it possible to reduce the impact on the components of the hoisting wire rope, the slinging wire rope, and the hoist, particularly at the time of ground cutting, due to the deformation of the hoisting wire rope between the gaps g. This significantly improves the safety of the use of the drum and extends the life of the hoist.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a wire drum showing an example of the present invention.

FIG. 2 is a sectional view of a screw groove provided on a peripheral surface of a wire drum.

FIG. 3 is a perspective view illustrating a configuration of a hoist.

FIG. 4 is a cross-sectional view of a thread groove provided on a peripheral surface of a conventional wire drum.

[Explanation of symbols]

 5 Wire rope for hoisting 9 Wire drum 10 Screw groove D1 Pitch circle diameter D2 Pitch circle diameter

Claims (1)

[Utility model registration claims] 1. A wire drum for winding or unwinding a winding wire rope on a peripheral surface, wherein the winding wire rope is wound with a large diameter peripheral surface to which a winding start end of the winding wire rope is assigned. The small-diameter peripheral surface to which the take-up end is assigned is continuously connected by a tapered peripheral surface, and a groove having a substantially V-shaped cross section for guiding the winding wire rope is formed in each of the peripheral surfaces in a screw shape. Wherein the substantially V-shaped section has a cross-sectional shape such that the hoisting wire rope does not adhere to the groove bottom when no load is applied, and the hoisting wire rope abuts the groove bottom when load is applied. Wire drum for electric hoist.