A spiral steel pipe leveling machine downward pressure limit protection circuit

Abstract

The utility model discloses a spiral steel pipe leveling machine downward pressure limit protection circuit, which relates to the technical field of steel pipe processing equipment, including a power supply, a downward pressure motor main circuit and a start-stop control circuit. The power supply includes a three-phase power supply, a neutral line and a grounding line; one end of the downward pressure motor main circuit is connected to the three-phase power supply, and the other end is connected to the grounding line after being connected in series with the downward pressure motor; one end of the start-stop control circuit is connected to the L of the three-phase power supply 1 The utility model uses the circuit to limit the downward pressure of the leveling machine, thereby ensuring the downward pressure standard of the steel coil, protecting the running stability of the equipment, and improving the quality of the steel pipe.

Description

Technical Field

[0001] The utility model relates to the technical field of steel pipe processing equipment, in particular to a downward pressure limit protection circuit of a spiral steel pipe leveling machine. Background Art

[0002] The leveler is the core equipment of the spiral steel pipe winding machine. The steel coil can only be rolled after it has been flattened and shaped by the leveler. The flatness of the steel coil directly affects the subsequent quality of the steel pipe. In the prior art, the leveler is driven by a motor and there is no corresponding limit control protection circuit. In addition, the bending degree of the steel coil is different, and the corresponding degree of pressure is also different. In actual operation, the pressure of the leveler roller is determined entirely by the operator's experience. This not only wastes manual effort, but also affects the stability of the equipment operation due to the limited manual effort, resulting in frequent damage to the leveler roller bearing and overload and burning of the pressure motor. Utility Model Content

[0003] In order to overcome the deficiencies of the above-mentioned prior art, the utility model provides a spiral steel pipe leveling machine downward pressure limit protection circuit, which uses the circuit to limit the downward pressure degree of the leveling machine, thereby ensuring the downward pressure standard of the steel coil, protecting the equipment operation stability, and improving the quality of the steel pipe.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A spiral steel pipe leveling machine downward pressure limit protection circuit includes a power supply, a downward pressure motor main circuit and a start-stop control circuit, and the power supply includes a three-phase power supply, a neutral line and a grounding line;

[0006] One end of the main circuit of the pressure motor is connected to the three-phase power supply, and the other end is connected in series with the pressure motor and then connected to the ground wire;

[0007] One end of the start-stop control circuit is connected to the L1 end of the three-phase power supply, and the other end is connected to the neutral line.

[0008] As a further implementation, the start-stop control circuit includes a downward pressure start-stop control circuit and an upward pressure start-stop control circuit, and the downward pressure start-stop control circuit and the upward pressure start-stop control circuit are connected in parallel and interlocked with each other.

[0009] As a further implementation method, auxiliary contacts of a thermal relay and an emergency stop switch are connected in series between the parallel structure composed of the downward start-stop control circuit and the upward start-stop control circuit and the L1 end of the three-phase power supply.

[0010] As a further implementation method, a downward pressure start switch, two intermediate relays, and auxiliary contacts of the first contactor are sequentially connected in series in the downward pressure start-stop control circuit.

[0011] As a further implementation, the two intermediate relays are respectively a first intermediate relay and a second intermediate relay.

[0012] As a further implementation, the main circuit of the downward pressure motor includes two AC contactors, and the two AC contactors are respectively a first AC contactor and a second AC contactor.

[0013] As a further implementation manner, two AC contactors are connected in parallel and interlocked with each other.

[0014] As a further implementation, one end of the parallel structure formed by the two AC contactors is connected to an air circuit breaker, and one end of the air circuit breaker away from the parallel structure formed by the two AC contactors is connected to a three-phase power supply.

[0015] As a further implementation, a thermal relay is connected in series to the other end of the parallel structure composed of the two AC contactors, and one end of the thermal relay away from the parallel structure composed of the two AC contactors is connected to the pressure motor.

[0016] As a further implementation method, one end of the pressure motor away from the thermal relay is grounded.

[0017] The beneficial effects of the above utility model are as follows:

[0018] The utility model provides a downward pressure limit protection circuit for a spiral steel pipe leveler, which uses the circuit to limit the downward pressure degree of the leveler. When the downward pressure degree of the downward pressure roller of the leveler exceeds the set threshold, the downward pressure limit protection circuit will control the output of the downward pressure motor, stop the downward pressure operation and issue an alarm reminder. While saving labor costs, it ensures the downward pressure standard of the steel coil, protects the operating stability of the equipment, and improves the quality of the steel pipe. Different limit values ​​can be set according to different thicknesses of plates, which reduces the technical requirements of the staff and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0020] Figure 1 The utility model discloses a circuit structure diagram of a downward pressure limit protection circuit of a spiral steel pipe leveling machine.

[0021] Among them, 11. power supply, 12. main circuit of downward pressure motor, 13. downward pressure start-stop control circuit, 14. upward start-stop control circuit. DETAILED DESCRIPTION

[0022] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0023] Embodiment 1

[0024] like Figure 1 As shown, this embodiment provides a downward pressure limit protection circuit for a spiral steel pipe leveler, including a power supply, a downward pressure motor main circuit and a start-stop control circuit, wherein the power supply includes a three-phase power supply, a neutral line and a ground line; one end of the downward pressure motor main circuit is connected to the three-phase power supply, and the other end is connected in series with the downward pressure motor and then connected to the ground line; one end of the start-stop control circuit is connected to the L1 end of the three-phase power supply, and the other end is connected to the neutral line. When the downward pressure degree of the downward pressure roller of the leveler exceeds the set threshold, the start-stop control circuit will be triggered, and the start-stop control circuit will be used to control the start and stop of the motor and then control the downward pressure roller of the leveler to stop the operation of continuing to press down. The downward pressure threshold of the downward pressure roller of the leveler can be set according to the thickness of different plates.

[0025] The start-stop control circuit includes a downward start-stop control circuit and an upward start-stop control circuit, which are connected in parallel and interlocked with each other. The auxiliary contacts of the thermal relay and the emergency stop switch are connected in series between the parallel structure composed of the downward start-stop control circuit and the upward start-stop control circuit and the L1 end of the three-phase power supply. In case of an emergency, the emergency stop switch can be operated to control the start and stop of the corresponding motor.

[0026] The down-pressure start-stop control circuit is connected in series with a down-pressure start switch, two intermediate relays and the first AC contactor auxiliary contact. The two intermediate relays are the first intermediate relay and the second intermediate relay. If one of them is activated and the other is not activated, the line can also be powered off and the protection effect can still be achieved.

[0027] The main circuit of the down-pressure motor includes two AC contactors, which are respectively a first AC contactor and a second AC contactor. The two AC contactors are connected in parallel and interlocked with each other. An air circuit breaker is connected to one end of the parallel structure composed of the two AC contactors, and the end of the air circuit breaker away from the parallel structure composed of the two AC contactors is connected to a three-phase power supply. A thermal relay is connected in series to the other end of the parallel structure composed of the two AC contactors, and the end of the thermal relay away from the parallel structure composed of the two AC contactors is connected to the down-pressure motor.

[0028] The working principle of this embodiment is:

[0029] When the device of the utility model is working, the existing PLC control is adopted to close the air circuit breaker QF1 in the main circuit of the upper and lower pressure motors, and at the same time, the starting switch SB1 in the pressure start and stop control circuit is pressed, the main contacts of the first AC contactor KM1 are energized and attracted, the pressure motor starts to run, driving the pressure screw to move, and the corresponding pressure roller starts to press down. The displacement sensor installed on the pressure roller records the corresponding pressure data and feeds it back to the PLC.

[0030] When the displacement sensor feedback data reaches the corresponding set threshold, the PLC controls the first intermediate relay KA1 and the second intermediate relay KA2 to operate, so that the normally closed contacts of the first intermediate relay KA1 and the second intermediate relay KA2 in the downward pressure start-stop control circuit are disconnected, the first AC contactor KM1 coil loses power, and the downward pressure motor stops running to prevent the roller from continuing to press down and causing damage to the bearing. At this time, the start switch SB2 in the upward start-stop control circuit is pressed, and the main contact of the second AC contactor KM2 is energized and attracted, and the upward motor starts to run, driving the downward pressure screw to move in the opposite direction, and the corresponding pressure roller begins to rise.

[0031] The utility model provides a spiral steel pipe leveling machine downward pressure limit protection circuit, which uses the circuit to limit the downward pressure degree of the leveling machine, thereby saving labor costs while ensuring the downward pressure standard of the steel coil, ensuring the stability of equipment operation, and improving the quality of the steel pipe.

[0032] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A spiral steel pipe leveling machine downward pressure limit protection circuit, characterized in that: It includes a power supply, a main circuit of a downward pressure motor and a start-stop control circuit, wherein the power supply includes a three-phase power supply, a neutral line and a ground line; One end of the main circuit of the downward pressure motor is connected to a three-phase power supply, and the other end is connected in series with the downward pressure motor and then connected to a ground wire; One end of the start-stop control circuit is connected to the L1 end of the three-phase power supply, and the other end is connected to the neutral line; The start-stop control circuit comprises a downward pressure start-stop control circuit and an upward pressure start-stop control circuit, and the downward pressure start-stop control circuit and the upward pressure start-stop control circuit are connected in parallel and interlocked with each other; The auxiliary contacts of the thermal relay and the emergency stop switch are connected in series between the parallel structure composed of the downward pressure start-stop control circuit and the upward pressure start-stop control circuit and the L1 end of the three-phase power supply; The pressure start-stop control circuit is connected in series with a pressure start switch, two intermediate relays and auxiliary contacts of the first AC contactor; The main circuit of the downward pressure motor includes two AC contactors, and the two AC contactors are respectively a first AC contactor and a second AC contactor; The two AC contactors are connected in parallel and interlocked with each other.

2. A spiral steel pipe leveling machine downward pressure limit protection circuit as claimed in claim 1, characterized in that: The two intermediate relays are respectively a first intermediate relay and a second intermediate relay.

3. A spiral steel pipe leveling machine downward pressure limit protection circuit as claimed in claim 1, characterized in that: One end of the parallel structure formed by the two AC contactors is connected to an air circuit breaker, and one end of the air circuit breaker away from the parallel structure formed by the two AC contactors is connected to a three-phase power supply.

4. A spiral steel pipe leveling machine downward pressure limit protection circuit as claimed in claim 3, characterized in that: The other end of the parallel structure formed by the two AC contactors is connected in series with a thermal relay, and one end of the thermal relay away from the parallel structure formed by the two AC contactors is connected to the pressure motor.

5. A spiral steel pipe leveling machine downward pressure limit protection circuit as claimed in claim 4, characterized in that: Connect the ground wire to one end of the pressure motor away from the thermal relay.

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