Safety protection device for electric hoist

Abstract

The utility model relates to a safety protection device for an electric hoist, which comprises a rope guide device, a rope guide device, a rope guide device and a rope guide device, wherein the rope guide device is used for neatly arranging steel wire ropes on a winding drum of the electric hoist; and the proximity switch is fixedly arranged on the rope guide, the proximity switch is used for sensing the position of a steel wire rope on a winding drum of the electric hoist, and when the proximity switch detects that the position of the steel wire rope on the winding drum of the electric hoist is changed, a normally open contact of a descending contactor coil 34 can be triggered to be disconnected so as to disconnect a descending loop of the electric hoist. According to the electric hoist safety protection device, whether the position of the steel wire rope is normal or not is detected through the sensor fixed to the steel wire rope guide, when the position of the steel wire rope deviates upwards, the sensor is triggered to disconnect a descending loop of the hoist, lap winding of the steel wire rope of the hoist is avoided, and the lap winding probability of the steel wire rope is reduced; the rope guider and the steel wire rope are protected; the modular design is adopted, and the sensor is replaced to adapt to steel wire ropes and winding drums of different models.

Description

Technical Field

[0001] The utility model relates to the technical field of electric hoists, in particular to a safety protection device for an electric hoist. Background Art

[0002] An electric hoist is a device for lifting installed on a crane equipment on a crane. Due to its small volume, light weight, simple operation and other characteristics, it is widely used in industrial and mining enterprises, warehousing industries and other fields. Common electric hoists include parts such as a machine body, a drum, a towing rope (steel wire rope), a wire rope guide, and a motor. The motor drives the drum to rotate, so that the lower end of the towing rope rises and falls.

[0003] Among them, the wire rope guide, also called a rope arranging device, is one of the accessories of the electric hoist. Its function is to enable the steel wire rope to be neatly arranged on the drum, so as to prevent the steel wire rope from being disordered, overlapping, etc., thereby causing mechanical failures of the electric hoist and damaging the electric hoist.

[0004] However, during actual use, when the hook under the electric hoist touches an obstacle or reaches the bottom, if the steel wire rope is still lowered continuously, the steel wire rope wound on the drum will become loose and deformed and be wound together layer by layer, and the steel wire ropes of each layer are wound on top of each other and are easily stuck; when it is found that the steel wire rope is loose, it is necessary to manually stop the machine to adjust the steel wire rope on the drum and rewind and arrange the steel wire rope on the drum. Since the steel wire rope is heavy, it takes a lot of time and manpower to rewind and arrange the steel wire rope, and at the same time, it affects the use of the electric hoist. Content of the Utility Model

[0005] Therefore, the technical problem to be solved by the utility model is to overcome the problem that when the steel wire rope of the hoist is lowered to the bottom and the operator does not stop the operation in time, it is very easy for the steel wire rope of the hoist to be overlapped. Once the overlap occurs, it is necessary to rewind the steel wire rope, which is time-consuming and laborious in the prior art.

[0006] To solve the above technical problem, the utility model provides a safety protection device for an electric hoist, including: a wire rope guide, which is arranged on the electric hoist, and the wire rope guide is used to neatly arrange the steel wire rope on the drum of the electric hoist; a proximity switch, at least one of which is arranged, and the proximity switch is fixedly arranged on the wire rope guide, and the proximity switch is used to sense the position of the steel wire rope on the drum of the electric hoist; a protection circuit, which includes a first power supply, a second power supply, a rising contactor coil and a falling contactor coil. The first power supply provides power for the electric hoist. The rising contactor coil and the falling contactor coil are connected in parallel to the second power supply, and the rising contactor coil and the falling contactor coil form an interlock. The normally open contacts of the rising contactor coil and the falling contactor coil are arranged in the power supply line between the first power supply and the electric hoist, and the proximity switch is connected in series on the branch where the falling contactor coil is located.

[0007] In one embodiment of the present utility model, the number of the proximity switches is set to two, and the two proximity switches are respectively located at the wire inlet position and the wire outlet position of the wire rope on the wire rope guide.

[0008] In one embodiment of the present utility model, the number of the proximity switches is set to a plurality, and the plurality of proximity switches are arranged in a circular array on the wire rope guide.

[0009] In one embodiment of the present utility model, the first power supply is AC380V.

[0010] In one embodiment of the present utility model, the second power supply is AC48V.

[0011] In one embodiment of the present utility model, a start button one is connected in series in the branch where the coil of the upward contactor is located.

[0012] In one embodiment of the present utility model, a start button two is connected in series in the branch where the coil of the downward contactor is located.

[0013] In one embodiment of the present utility model, the normally closed contact of the coil of the upward contactor is connected in series in the branch where the coil of the downward contactor is located.

[0014] In one embodiment of the present utility model, the normally closed contact of the coil of the downward contactor is connected in series in the branch where the coil of the upward contactor is located.

[0015] In one embodiment of the present utility model, when the proximity switch detects a change in the position of the wire rope on the drum of the electric hoist, the normally open contact of the coil of the downward contactor can be triggered to disconnect, so as to disconnect the downward circuit of the electric hoist.

[0016] The above technical solution of the present utility model has the following beneficial effects compared with the prior art:

[0017] For the electric hoist safety protection device of the present utility model, the sensor fixed on the wire rope guide is used to detect whether the position of the wire rope is normal. When the position of the wire rope deviates upward, the sensor is triggered to disconnect the downward circuit of the hoist, avoiding the overlapping winding of the wire rope of the hoist, reducing the probability of the wire rope overlapping winding; protecting the wire rope guide and the wire rope; adopting a modular design, and adapting to wire ropes and drums of different models by replacing the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to make the content of the present utility model easier to be clearly understood, the following further details the present utility model according to the specific embodiments of the present utility model and in conjunction with the attached drawings, wherein

[0019] Figure 1Structural schematic of the safety protection device for an electric hoist in a preferred embodiment of the present utility model Figure 1 ;

[0020] Figure 2 Structural schematic of the safety protection device for an electric hoist in a preferred embodiment of the present utility model Figure 2 ;

[0021] Figure 3 In a preferred embodiment of the present utility model Figure 1 Partial enlarged view of position A;

[0022] Figure 4 In a preferred embodiment of the present utility model Figure 2 Partial enlarged view of position B;

[0023] Figure 5 Circuit diagram of the protection circuit in a preferred embodiment of the present utility model

[0024] Explanation of reference numerals in the accompanying drawings: rope guide 1, proximity switch 2, protection circuit 3, power supply 1 31, power supply 2 32, up contactor coil 33, start button 1 331, down contactor coil 34, start button 2 341, electric hoist 100, steel wire rope 200 Detailed implementation manners

[0025] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present utility model and be able to implement it, but the embodiments cited are not intended to limit the present utility model

[0026] Refer to Figures 1-5As shown in the figure, the electric hoist safety protection device of the present utility model includes: a rope guide 1, a proximity switch 2, and a protection circuit 3; the rope guide 1 is arranged on the electric hoist, and the rope guide 1 is used to neatly arrange the steel wire rope on the drum of the electric hoist; the proximity switch 2 is provided with at least one, and the proximity switch 2 is fixedly arranged on the rope guide 1, and the proximity switch 2 is used to sense the position of the steel wire rope on the drum of the electric hoist; the protection circuit 3 includes a first power supply 31, a second power supply 32, a rising contactor coil 33, and a falling contactor coil 34. The first power supply 31 supplies power to the electric hoist. The rising contactor coil 33 and the falling contactor coil 34 are connected in parallel to the second power supply 32, and the rising contactor coil 33 and the falling contactor coil 34 form an interlock. The normally open contacts of the rising contactor coil 33 and the falling contactor coil 34 are arranged in the power supply line between the first power supply 31 and the electric hoist. The proximity switch 2 is connected in series to the branch where the falling contactor coil 34 is located. When the proximity switch 2 detects a change in the position of the steel wire rope on the drum of the electric hoist, it can trigger the normally open contact of the falling contactor coil 34 to disconnect, so as to disconnect the falling circuit of the electric hoist.

[0027] The working principle of the above electric hoist safety protection device is as follows:

[0028] Once the hook connected to the steel wire rope 200 of the electric hoist 100 encounters an obstacle or touches the ground, the steel wire rope on the drum of the electric hoist 100 is blocked by the steel wire rope below, resulting in the steel wire rope on the drum of the electric hoist 100 not being tightly wound on the drum of the electric hoist 100. Once the steel wire rope 200 wound on the drum of the electric hoist becomes loose, the positional relationship between the steel wire rope 200 and the proximity switch 2 will change. The proximity switch 2 sends a signal to the protection circuit 3, and the protection circuit 3 operates to cut off the normally open contact of the falling contactor coil 34, so that the electric hoist 100 stops descending, can timely detect that the steel wire rope is in place, and reduces the workload of maintaining the steel wire rope 200 in the later stage.

[0029] There are two ways to set the proximity switch 2. According to the cost and the detection effect that can be achieved, preferably, the number of the proximity switches 2 is set to two, and the two proximity switches 2 are respectively located at the wire inlet position and the wire outlet position of the steel wire rope on the rope guide 1.

[0030] Without considering the cost, the number of the proximity switches 2 is set to multiple, and the multiple proximity switches 2 are arranged in a circular array on the rope guide 1.

[0031] In the above circuit, the first power supply 31 is AC380V. The second power supply 32 is AC48V.

[0032] In the above circuit, a first start button 331 is connected in series to the branch where the rising contactor coil 33 is located. A second start button 341 is connected in series to the branch where the falling contactor coil 34 is located.

[0033] The interlock between the rising contactor coil 33 and the falling contactor coil 34 is that the normally closed contact of the rising contactor coil 33 is connected in series to the branch where the falling contactor coil 34 is located. The normally closed contact of the falling contactor coil 34 is connected in series to the branch where the rising contactor coil 33 is located.

[0034] Obviously, the above embodiments are only examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the creation of the present utility model.

Claims

1. An electric hoist safety protection device, characterized in that: Including, A wire guide, which is arranged on an electric hoist, and the wire guide is used to neatly arrange the steel wire rope on the drum of the electric hoist; A proximity switch, which is set to at least one, and the proximity switch is fixedly arranged on the wire guide, and the proximity switch is used to sense the position of the steel wire rope on the drum of the electric hoist; A protection circuit, which includes a first power supply, a second power supply, a rising contactor coil and a falling contactor coil. The first power supply provides power for the electric hoist. The rising contactor coil and the falling contactor coil are connected in parallel to the second power supply, and the rising contactor coil and the falling contactor coil form an interlock. The normally open contacts of the rising contactor coil and the falling contactor coil are arranged in the power supply line between the first power supply and the electric hoist, and the proximity switch is connected in series in the branch where the falling contactor coil is located.

2. The electric hoist safety protection device according to claim 1, characterized in that: The number of the proximity switches is set to two, and the two proximity switches are respectively located at the wire inlet position and the wire outlet position of the steel wire rope on the wire guide.

3. The electric hoist safety protection device according to claim 1, characterized in that: The number of the proximity switches is set to multiple, and the multiple proximity switches are arranged in a circular array on the wire guide.

4. The electric hoist safety protection device according to claim 1, characterized in that: The first power supply is AC380V.

5. The electric hoist safety protection device according to claim 2, characterized in that: The second power supply is AC48V.

6. The safety protection device for an electric hoist according to claim 1, characterized in that: A start button one is connected in series in the branch where the rising contactor coil is located.

7. The electric hoist safety protection device according to claim 6, characterized in that: A start button two is connected in series in the branch where the falling contactor coil is located.

8. The safety protection device for electric hoist according to claim 1, characterized in that: The normally closed contact of the rising contactor coil is connected in series in the branch where the falling contactor coil is located.

9. The electric hoist safety protection device according to claim 8, wherein: The normally closed contact of the falling contactor coil is connected in series in the branch where the rising contactor coil is located.

10. The safety protection device for electric hoist according to claim 1, characterized in that: When the proximity switch detects a change in the position of the steel wire rope on the drum of the electric hoist, it can trigger the normally open contact of the falling contactor coil to disconnect to cut off the falling circuit of the electric hoist.

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