Control devices and control systems for lifting equipment

Abstract

This disclosure provides a control device and control system for a lifting device. The control device includes a driver, a first contactor, and a first limit switch. The first limit switch is used to disconnect when the lifting device reaches a first height during operation. The lifting device includes a motor. The first voltage output terminal of the driver is connected to one end of the motor through the first main contact of the first contactor. The second voltage output terminal of the driver is connected to the other end of the motor through the second main contact of the first contactor. One end of the normally open contact of the first contactor is connected to the first signal input terminal of the driver. The other end of the normally open contact of the first contactor is connected to one end of the first limit switch. The other end of the first limit switch is connected to the second signal input terminal of the driver. The driver is used to stop outputting voltage when the connection between the first signal input terminal and the second signal input terminal is broken. When the lifting device exceeds the set height, the motor is cut off in an emergency, improving the operational safety of the lifting device.

Description

Technical Field

[0001] This disclosure relates to the field of lifting equipment control technology, and in particular to a control device and control system for lifting equipment. Background Technology

[0002] Existing lifting equipment generally uses a limit switch connected in series in the coil control circuit of the contactor to ensure that the lifting equipment can automatically stop when it reaches the preset height, preventing the equipment from exceeding the safe operating range. However, during long-term operation, the contactor may experience structural jamming or contact sticking. These faults will cause the lifting equipment to fail to cut off the power when it reaches the set limit switch height, thereby increasing the risk of safety accidents and posing serious safety hazards to the safe operation of the lifting equipment. Summary of the Invention

[0003] The technical problem to be solved by this disclosure is to overcome the defect in the prior art that the lifting equipment cannot stop operating at a limited height due to contactor failure, and to provide a control device and control system for the lifting equipment.

[0004] This disclosure solves the above-mentioned technical problems through the following technical solution:

[0005] In a first aspect, a control device for a lifting device is provided, the control device including a driver, a first contactor, and a first limiter; the first limiter is used to disconnect when the lifting device runs to a first height, and the lifting device includes a motor.

[0006] The first voltage output terminal of the driver is connected to one end of the motor through the first main contact of the first contactor, and the second voltage output terminal of the driver is connected to the other end of the motor through the second main contact of the first contactor;

[0007] One end of the normally open contact of the first contactor is connected to the first signal input terminal of the driver, and the other end of the normally open contact of the first contactor is connected to one end of the first limit switch.

[0008] The other end of the first limit switch is connected to the second signal input terminal of the driver, which is used to stop the output voltage when the connection between the first signal input terminal and the second signal input terminal is broken.

[0009] Optionally, the control device further includes a second contactor and a second limiter, wherein the second limiter is used to disconnect when the lifting device descends to a second height, and the first limiter is specifically used to disconnect when the lifting device rises to a first height, wherein the second height is lower than the first height; the coil of the first contactor and the coil of the second contactor do not operate simultaneously;

[0010] One end of the motor is connected to the first voltage output terminal of the driver through the first main contact of the second contactor, and the other end of the motor is connected to the second voltage output terminal of the driver through the second main contact of the second contactor;

[0011] One end of the normally open contact of the second contactor is connected to the third signal input terminal of the driver, and the other end of the normally open contact of the second contactor is connected to one end of the second limit switch.

[0012] The other end of the second limiter is connected to the fourth signal input terminal of the driver, which is used to stop outputting voltage when the connection between the third signal input terminal and the fourth signal input terminal is broken.

[0013] Optionally, the control device further includes a third limiter, which is used to disengage when the lifting device rises to a third height, the third height being lower than the first height;

[0014] One end of the third limiter is connected to the power supply, and the other end of the third limiter is grounded through the coil of the first contactor.

[0015] Optionally, the control device further includes a first start button; one end of the first start button is connected to the power supply, the other end of the first start button is connected to one end of the third limit switch, and the other end of the third limit switch is grounded through the coil of the first contactor.

[0016] Optionally, the control device further includes a first stop button; the first stop button is located between the power supply and the first start button.

[0017] Optionally, the control device further includes a fourth limiter, which is used to disengage when the lifting device descends to a fourth height; the fourth height is higher than the second height.

[0018] One end of the fourth limiter is connected to the power supply, and the other end of the fourth limiter is grounded through the coil of the second contactor.

[0019] Optionally, the control device further includes a second start button; one end of the second start button is connected to the power supply, and the other end of the second start button is connected to one end of the fourth limit switch, and the other end of the fourth limit switch is grounded through the coil of the second contactor.

[0020] Optionally, the control device further includes a second stop button; the second stop button is located between the power supply and the second start button.

[0021] Optionally, the control device includes an alarm device; the alarm device is used to sound an alarm when the first limit switch is disconnected.

[0022] In a second aspect, a control system for a lifting device is provided, the control system comprising the control device and the lifting device as described in the first aspect.

[0023] Based on common knowledge in the field, the above optional conditions can be combined arbitrarily to obtain various preferred embodiments of this disclosure.

[0024] The positive and progressive effects of this disclosure are as follows: when the lifting equipment reaches the first height set by the first limit switch, the first limit switch will be triggered, automatically disconnecting the connection circuit between the first signal input terminal and the second signal input terminal in the driver, causing the driver to be unable to output voltage to the motor, thereby stopping the motor. Therefore, even if the contactor fails, once the lifting equipment exceeds the safe height, the control device can still quickly apply emergency braking to the motor, significantly improving the operational safety of the lifting equipment and protecting the safety of the equipment and personnel. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the control device structure of a lifting device provided in Embodiment 1 of this disclosure;

[0026] Figure 2 This is a schematic diagram of a control device with self-locking and interlocking mechanisms provided in Embodiment 1 of this disclosure. Detailed Implementation

[0027] The present disclosure is further illustrated below by way of embodiments, but the present disclosure is not limited to the scope of the embodiments described herein.

[0028] The prefixes such as "first" and "second" used in this disclosure are merely for distinguishing different descriptive objects and do not limit the position, order, priority, quantity, or content of the described objects. The use of ordinal numbers and other prefixes used to distinguish descriptive objects in this disclosure does not constitute a limitation on the described objects. The description of the described objects is given in the claims or the context of the embodiments, and should not be construed as an unnecessary limitation. Furthermore, in the description of this embodiment, unless otherwise stated, "multiple" means two or more.

[0029] Example 1

[0030] This embodiment provides a control device for a lifting device, such as... Figure 1As shown, the control device includes a driver 101, a first contactor, and a first limiter 102. The first limiter 102 is used to disconnect when the lifting device reaches a first height. The lifting device includes a motor 103. The first voltage output terminal 105 of the driver 101 is connected to one end of the motor 103 through the first main contact 104 of the first contactor, and the second voltage output terminal 107 of the driver 101 is connected to the other end of the motor 103 through the second main contact 106 of the first contactor. One end of the normally open contact 108 of the first contactor is connected to the first signal input terminal 109 of the driver 101, and the other end of the normally open contact 108 is connected to one end of the first limiter 102. The other end of the first limiter 102 is connected to the second signal input terminal 110 of the driver 101. The driver 101 is used to stop outputting voltage when the connection between the first signal input terminal 109 and the second signal input terminal 110 is broken.

[0031] In practice, the driver is responsible for supplying power to the motor to drive the lifting equipment. During this process, the two main contacts and normally open contacts of the first contactor are all closed, ensuring voltage transmission between the driver and the motor, as well as the connection between the first signal input terminal and the second signal input terminal. When the driver detects the connection between the first signal input terminal and the second signal input terminal, it outputs voltage to the motor, and the motor starts to run. When the lifting equipment reaches the first height set by the first limit switch, the first limit switch will be triggered to disconnect. When the driver detects the interruption of the connection between the first signal input terminal and the second signal input terminal, it will stop supplying power to the motor, the motor will stop running, and the lifting equipment will also stop running. This ensures that the lifting equipment can automatically stop when it reaches the preset safe height, thereby ensuring the safety of operation.

[0032] In one alternative implementation, such as Figure 1 As shown, the control device also includes a second contactor and a second limiter 111. The second limiter 111 is used to disconnect when the lifting equipment descends to a second height, and the first limiter 102 is specifically used to disconnect when the lifting equipment rises to a first height. The second height is lower than the first height. The coils of the first contactor and the second contactor do not work simultaneously.

[0033] One end of the motor 103 is connected to the first voltage output terminal 105 of the driver through the first main contact 113 of the second contactor, and the other end of the motor 103 is connected to the second voltage output terminal 107 of the driver 101 through the second main contact 112 of the second contactor.

[0034] One end of the normally open contact 1114 of the second contactor is connected to the third signal input terminal 115 of the driver, and the other end of the normally open contact 114 of the second contactor is connected to one end of the second limit switch 111.

[0035] The other end of the second limiter 111 is connected to the fourth signal input terminal 116 of the driver, which is used to stop the output voltage when the connection between the third signal input terminal 115 and the fourth signal input terminal 116 is broken.

[0036] In practical implementation, the control device of the lifting equipment is also equipped with a second contactor and a second limit switch to ensure that the equipment operates within the set safety range. The second limit switch is responsible for setting the minimum descent height of the lifting equipment, i.e., the second height, while the first limit switch is responsible for limiting the maximum ascent height of the lifting equipment, i.e., the first height. Since the second height is lower than the first height, the interval between the two heights constitutes the safe operating range of the lifting equipment. Specifically, during the descent of the lifting equipment, when the lifting equipment descends to the second height set by the second limit switch, the second limit switch will be triggered and disconnected, causing the connection between the third signal input terminal and the fourth signal input terminal to be interrupted. Similarly, during the ascent of the lifting equipment, when the lifting equipment rises to the first height set by the first limit switch, the first limit switch will be triggered and disconnected, causing the connection between the first signal input terminal and the second signal input terminal to be interrupted. Once the driver detects the disconnection between the first signal input terminal and the second signal input terminal, or detects the disconnection between the third signal input terminal and the fourth signal input terminal, the driver will stop supplying power to the motor, causing the motor to stop running, thereby stopping the lifting equipment. This ensures that the lifting equipment can automatically stop when it reaches the preset safe height. To avoid the motor receiving both ascent and descent commands simultaneously, the coils of the first contactor and the second contactor cannot work simultaneously, ensuring that the lifting equipment can only move in one direction at any time, further enhancing operational safety and equipment stability.

[0037] In a specific example, when the driver detects a connection between the first signal input terminal and the second signal input terminal, it outputs a positive voltage to make the motor rotate forward, thereby driving the lifting device to rise. When the driver detects a connection between the third signal input terminal and the fourth signal input terminal, it outputs a negative voltage to make the motor rotate in reverse, thereby driving the lifting device to descend.

[0038] In another specific example, when the driver detects a connection between the first signal input terminal and the second signal input terminal, it outputs a negative voltage to reverse the motor and drive the lifting device to descend. When the driver detects a connection between the third signal input terminal and the fourth signal input terminal, it outputs a positive voltage to rotate the motor forward and drive the lifting device to ascend.

[0039] In one optional embodiment, the control device further includes a third limiter, which is used to disconnect when the lifting device rises to a third height, which is lower than the first height; one end of the third limiter is connected to the power supply, and the other end of the third limiter is grounded through the coil of the first contactor.

[0040] In practice, the third limit switch is set at a third height that is lower than the first height set by the first limit switch. The third height serves as the first safety checkpoint during the lifting process. The third limit switch, the coil of the first contactor, and the power supply form a power supply circuit. When the lifting equipment rises to the third height, the third limit switch is triggered and automatically disconnects this power supply circuit. Once the third limit switch disconnects the power supply circuit, the power supply will stop supplying power to the coil of the first contactor, causing the coil to release. After the coil releases, the first main contact and the second main contact of the first contactor connected to the motor will also disconnect accordingly, cutting off the connection between the motor and the driver, causing the motor to stop working, and thus stopping the continued operation of the lifting equipment.

[0041] In a specific example, when the lifting equipment reaches the third height, a contactor malfunction causes the motor to fail to shut off properly, and the lifting equipment continues to rise to the first height. At this point, the first limit switch will be triggered, directly cutting off the signal transmission between the first and second signal input terminals of the driver, thereby cutting off the power supply to the motor and forcibly stopping the operation of the lifting equipment. By setting two different rising heights, the control device provides a dual safety guarantee mechanism. The third limit switch acts as the first line of defense, cutting off the power supply at a lower height to prevent the equipment from exceeding the safe operating range, while the first limit switch acts as a backup safety measure, ensuring that the equipment stops operating when it reaches a higher but still safe height if the lifting equipment fails to stop at the third height. This improves the safety and reliability of the lifting equipment.

[0042] In one optional embodiment, the control device further includes a first start button; one end of the first start button is connected to a power source, and the other end of the first start button is connected to one end of a third limit switch, and the other end of the third limit switch is grounded through the coil of a first contactor.

[0043] In practice, the first start button is a trigger button for the operator to manually start the lifting equipment. By triggering the first start button, the lifting equipment can be controlled to start rising. One end of the first start button is connected to the power supply, and the other end is connected to one end of the third limit switch. The other end of the third limit switch is grounded through the coil of the first contactor. When the operator presses the first start button, the power supply circuit is connected, the current flows through the coil of the first contactor, the coil is attracted, the two main contacts of the first contactor are also closed, the driver outputs voltage to the motor, and the lifting equipment starts to move upward. The first start button provides the operator with a simple and direct way to start the lifting equipment's upward movement.

[0044] In one optional embodiment, the control device further includes a first stop button; the first stop button is located between the power supply and the first start button.

[0045] In practice, the control device is also equipped with a first stop button. The operator can trigger the first stop button to control the lifting equipment to stop in an emergency during the lifting process. The first stop button is located in the connection line between the first start button and the power supply. When the operator presses the first stop button, the power supply circuit is cut off, the coil of the first contactor loses power, causing the coil to release, and the first main contact and the second main contact of the first contactor will disconnect. The motor will stop running and the lifting equipment will also stop running.

[0046] In a specific example, the connection order between the first stop button, the first start button, the third limit switch, and the coil of the first contactor can be adjusted according to the actual application scenario.

[0047] In one optional embodiment, the control device further includes a fourth limiter for disengaging when the lifting device descends to a fourth height; the fourth height is higher than the second height; one end of the fourth limiter is connected to a power source, and the other end of the fourth limiter is grounded through the coil of the second contactor.

[0048] In practice, the fourth limit switch is set at a fourth height that is higher than the second height set by the second limit switch. The fourth height serves as the first safety checkpoint during the descent of the lifting equipment. The coils of the fourth limit switch, the second contactor, and the power supply constitute a power supply circuit. When the lifting equipment descends to the fourth height, the fourth limit switch is triggered, automatically disconnecting this power supply circuit. Once the fourth limit switch disconnects the power supply circuit, the power supply will stop supplying power to the coil of the second contactor, causing the coil to release. After the coil releases, the first and second main contacts of the second contactor connected to the motor will also disconnect accordingly, cutting off the connection between the motor and the driver, causing the motor to stop working, and thus stopping the continued operation of the lifting equipment.

[0049] In a specific example, when the lifting equipment descends to the fourth height, a contactor malfunction causes the motor to fail to shut off properly. The lifting equipment will continue to descend to the second height, at which point the second limit switch will be triggered, directly cutting off the signal transmission between the third and fourth signal input terminals of the driver, thereby cutting off the power supply to the motor and forcibly stopping the lifting equipment. By setting two different descent heights, the control device provides a dual safety guarantee mechanism. The fourth limit switch acts as the first line of defense during descent, cutting off the power supply at a higher position to prevent the lifting equipment from exceeding the safe operating range. The second limit switch, on the other hand, serves as a backup safety measure, ensuring that the equipment stops when it reaches a lower but still safe height if the lifting equipment fails to stop at the fourth height. This improves the safety and reliability of the lifting equipment.

[0050] In one optional embodiment, the control device further includes a second start button; one end of the second start button is connected to a power source, and the other end of the second start button is connected to one end of a fourth limit switch, and the other end of the fourth limit switch is grounded through the coil of a second contactor.

[0051] In practice, the operator manually triggers the second start button to control the lifting equipment to begin descending. One end of the second start button is connected to the power supply, and the other end is connected to one end of the fourth limit switch. The other end of the fourth limit switch is grounded through the coil of the second contactor. When the operator presses the second start button, the power supply circuit is connected, current flows through the coil of the second contactor, the coil is attracted, and the two main contacts of the second contactor are also closed. The driver outputs voltage to the motor, and the lifting equipment begins to move downward. The second start button provides the operator with a simple and direct way to start and control the descent of the lifting equipment.

[0052] In one optional embodiment, the control device further includes a second stop button; the second stop button is located between the power supply and the second start button.

[0053] In practice, the control device is also equipped with a second stop button. By triggering the second stop button, the operator can achieve an emergency stop during the operation of the lifting equipment. The second stop button is located in the connection line between the second start button and the power supply. When the operator presses the second stop button, the power supply circuit is cut off, the coil of the second contactor loses power, causing the coil to release, the first main contact and the second main contact of the second contactor to disconnect, the motor stops running, and the lifting equipment also stops running.

[0054] In a specific example, the connection order between the second stop button, the second start button, the fourth limit switch, and the coil of the second contactor can be adjusted according to the actual application scenario.

[0055] In one alternative embodiment, the control device includes an alarm device; the alarm device is used to sound an alarm when the first limit switch is disconnected.

[0056] In practice, the control device is equipped with an alarm device to warn the staff when the equipment reaches the boundary of the safe operating range. When the first limit switch is disconnected, it indicates that the lifting equipment has reached the boundary of the set safe operating range. At this time, the alarm device emits an audible and visual alarm signal or other forms of alarm signal to attract the staff's attention.

[0057] In another alternative implementation, the alarm device can also be used to trigger an alarm when the second, third, or fourth limit switch is disconnected.

[0058] In practice, if any limit switch in the control device is disconnected, it means that the lifting equipment has reached the set height. At this time, the alarm device can remind the operator to perform the corresponding operation to ensure the safety of the lifting equipment.

[0059] In a specific example, such as Figure 2 As shown, the power supply 117, the first stop button 118, the first start button 119, the first self-locking contact 120, the first interlocking contact 121, the third limit switch 122, and the coil 123 of the first contactor constitute the lifting control circuit of the lifting equipment. When the first start button 119 is closed, the first stop button 118, the first self-locking contact 120, the first interlocking contact 121, and the third limit switch 122 are all closed. At this time, the coil 123 of the first contactor is energized and attracted, thereby enabling... Figure 1 In the diagram, the first main contact 104, the second main contact 106, and the normally open contact 108 of the first contactor are all closed. The driver detects the connection between the first signal input terminal 109 and the second signal input terminal 110, and outputs a positive voltage to the motor 103, causing the motor 103 to reverse, thereby driving the lifting device to start rising. The first self-locking contact 120 can maintain the energized state of the coil 123 of the first contactor, so even if the first start button 119 is released, the lifting device can continue to operate until the first stop button 118 is triggered, or the lifting device rises to the height limited by the third limiter 122, at which point the lifting device will stop operating. Figure 2 As shown, the second stop button 124, the second start button 125, the second self-locking contact 126, the second interlocking contact 127, the fourth limit switch 128, and the coil 129 of the second contactor constitute the lowering power supply circuit of the lifting device. When the second start button 125 is triggered, the second stop button 124, the second self-locking contact 126, the second interlocking contact 127, and the fourth limit switch 128 all close, and the coil 129 of the second contactor is energized and attracted, causing... Figure 1The first main contact 113, the second main contact 114, and the normally open contact 114 of the second contactor shown in the diagram are all closed. The driver detects the connection between the third signal input terminal 115 and the fourth signal input terminal 116 and outputs a negative voltage to the motor 103, causing the motor 103 to reverse, thereby driving the lifting device to start descending. The second self-locking contact 126 can keep the coil 129 of the second contactor energized to achieve continuous control. Even if the second start button 125 is released, the lifting device can continue to run until the second stop button 124 is triggered, or the lifting device descends to the height limited by the fourth limiter 128. At this time, the lifting device will stop running. When the coil 123 of the first contactor is energized, the second interlocking contact 127 will open, disconnecting the descent power supply circuit. The first interlocking contact 121 and the second interlocking contact 127 can prevent the two contactors from being energized at the same time, ensuring that the rising and falling actions of the lifting device will not be performed simultaneously, thus ensuring operational safety.

[0060] Example 2

[0061] This embodiment provides a control system for a lifting device, which includes a control device as described in Embodiment 1 and the lifting device.

[0062] In this embodiment, the control system consists of two parts: a control device and a lifting device. The control device is built into the lifting device and can accurately control the operating height of the lifting device. Once it is detected that the lifting device exceeds the preset safe height limit, the control device will automatically cut off the power to protect the safety of the lifting device and the operator.

[0063] While specific embodiments of this disclosure have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this disclosure is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this disclosure, but all such changes and modifications fall within the scope of protection of this disclosure.

Claims

1. A control device for a lifting device, characterized in that, The control device includes a driver, a first contactor, and a first limit switch; the first limit switch is used to disconnect when the lifting device reaches a first height, and the lifting device includes a motor. The first voltage output terminal of the driver is connected to one end of the motor through the first main contact of the first contactor, and the second voltage output terminal of the driver is connected to the other end of the motor through the second main contact of the first contactor; One end of the normally open contact of the first contactor is connected to the first signal input terminal of the driver, and the other end of the normally open contact of the first contactor is connected to one end of the first limit switch. The other end of the first limit switch is connected to the second signal input terminal of the driver, which is used to stop the output voltage when the connection between the first signal input terminal and the second signal input terminal is broken; The control device further includes a second contactor and a second limiter. The second limiter is used to disconnect when the lifting device descends to a second height, and the first limiter is specifically used to disconnect when the lifting device rises to a first height, wherein the second height is lower than the first height. The coil of the first contactor and the coil of the second contactor do not operate simultaneously; One end of the motor is connected to the first voltage output terminal of the driver through the first main contact of the second contactor, and the other end of the motor is connected to the second voltage output terminal of the driver through the second main contact of the second contactor; One end of the normally open contact of the second contactor is connected to the third signal input terminal of the driver, and the other end of the normally open contact of the second contactor is connected to one end of the second limit switch. The other end of the second limiter is connected to the fourth signal input terminal of the driver, which is used to stop outputting voltage when the connection between the third signal input terminal and the fourth signal input terminal is broken; the control device also includes a third limiter, which is used to disconnect when the lifting device rises to a third height, the third height being lower than the first height; One end of the third limiter is connected to the power supply, and the other end of the third limiter is grounded through the coil of the first contactor.

2. The control device as described in claim 1, characterized in that, The control device also includes a first start button; One end of the first start button is connected to the power source, and the other end of the first start button is connected to one end of the third limit switch. The other end of the third limit switch is grounded through the coil of the first contactor.

3. The control device as described in claim 2, characterized in that, The control device also includes a first stop button; The first stop button is located between the power supply and the first start button.

4. The control device as described in claim 1, characterized in that, The control device further includes a fourth limiter, which is used to disengage when the lifting device descends to a fourth height; the fourth height is higher than the second height. One end of the fourth limiter is connected to the power supply, and the other end of the fourth limiter is grounded through the coil of the second contactor.

5. The control device as described in claim 4, characterized in that, The control device also includes a second start button; One end of the second start button is connected to the power supply, and the other end of the second start button is connected to one end of the fourth limit switch. The other end of the fourth limit switch is grounded through the coil of the second contactor.

6. The control device as described in claim 5, characterized in that, The control device also includes a second stop button; The second stop button is located between the power supply and the second start button.

7. The control device as claimed in claim 1, characterized in that, The control device includes an alarm device; The alarm device is used to sound an alarm when the first limit switch is disconnected.

8. A control system for a lifting device, characterized in that, The control system includes a control device and a lifting device as described in any one of claims 1 to 7.

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