Single button forward and reverse automatic stop control circuit

Abstract

The invention discloses a single-button forward and reverse automatic stop control circuit, which comprises a secondary line power port A and a power port B externally connected to a 220V AC power supply, a forward contactor KM1, a reverse contactor KM2, a forward intermediate relay KA1, a reverse intermediate relay KA2, a reversing intermediate relay KA3, a thermal relay FR, a forward time relay KT1, a reverse time relay KT2, bipolar circuit breakers QF1 and QF2, a button SB, and a forward indicator light HD1 and a reverse indicator light HD2. The circuit is simple, easy to operate, reliable in operation, and realizes multiple protections. The wrong forward and reverse buttons will not be pressed to cause mechanical accidents, and the short circuit accident of the power supply will not be caused, thereby ensuring the normal operation of the equipment.

Description

Technical Field

[0001] The invention relates to a control circuit, in particular to a forward and reverse rotation automatic stop control circuit. Background Art

[0002] In the field of industrial manufacturing, the motor needs to be rotated forward and reverse in daily use. It can be said that the forward and reverse rotation of the motor is widely used. For example, cranes, electric planers for woodworking, bench drills, wire cutters, spin dryers and lathes. In order to enable the motor to rotate forward and reverse, two contactors KM1 and KM2 can be used to switch the phase sequence of the three-phase power supply of the motor. Traditional circuits generally use three buttons: forward button, reverse button, and stop button. However, it is easy to make mistakes in operation and press the wrong button, causing mechanical accidents. Or the two contactors are closed at the same time, causing a short circuit accident of the power supply. Summary of the invention

[0003] The purpose of the present invention is to provide a single-button forward and reverse automatic stop control circuit, which uses one button to control the forward and reverse switching of a motor, has a simple circuit, is easy to operate, runs reliably, and realizes multiple protections.

[0004] To achieve the above-mentioned purpose, the single-button forward and reverse automatic stop control circuit of the present invention includes a secondary line power port A and a power port B of an external 220V AC power supply, and also includes a forward contactor KM1, a reverse contactor KM2, a forward intermediate relay KA1, a reverse intermediate relay KA2, a reversing intermediate relay KA3, a thermal relay FR, a forward time relay KT1, a reverse time relay KT2, a bipolar circuit breaker QF1 and QF2, a button SB, and a forward indicator light HD1 and a reverse indicator light HD2.

[0005] After the secondary line power supply port A is connected to the bipolar circuit breaker QF1, it is connected in parallel with the upper end of the button SB, the upper end of the normally open contact KA1-2 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-2 of the reversing intermediate relay KA3, the upper end of the delayed disconnection normally open contact of the forward time relay KT1, and the upper end of the delayed disconnection normally open contact of the reverse time relay KT2.

[0006] The lower end of the button SB is connected in parallel with the upper end of the normally closed contact of the reversing intermediate relay KA3, the upper end of the normally open contact KA1-1 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-1 of the reversing intermediate relay KA3, and the upper end of the normally open contact of the reversing intermediate relay KA2.

[0007] After the lower end of the normally closed contact of the reversing intermediate relay KA3 is connected in parallel with the lower end of the normally open contact KA1-1 of the forward intermediate relay KA1, the normally closed contact KA2-1 of the reversing intermediate relay is connected in series, and then connected in parallel with the upper end of the coil of the forward intermediate relay KA1 and the upper end of the coil of the forward time relay KT1.

[0008] After the lower end of the normally open contact KA3-1 of the reversing intermediate relay and the lower end of the normally open contact of the reversing intermediate relay KA2 are connected in parallel, the normally closed contact of the forward intermediate relay KA1 is connected in series, and then connected in parallel with the upper end of the coil of the reversing intermediate relay KA2 and the upper end of the coil of the reversing time relay KT2.

[0009] The lower end of the normally open contact KA1-2 of the forward intermediate relay and the lower end of the normally open contact KA3-2 of the reversing intermediate relay are connected in parallel, and then the normally closed contact KA2-2 of the reversing intermediate relay is connected in series, and connected to the upper end of the coil of the reversing intermediate relay KA3.

[0010] The forward time relay KT1 delays disconnecting the lower end of the normally open contact connected in series with the normally closed contact of the reversing contactor KM2, and then is connected in parallel with the upper end of the coil of the forward contactor KM1 and the upper end of the forward indicator light HD1.

[0011] The reversing time relay KT2 delays disconnecting the lower end of the normally open contact in series with the normally closed contact of the forward contactor KM1, and then is connected in parallel with the upper end of the coil of the reversing contactor KM2 and the upper end of the reversing indicator light HD2.

[0012] The lower end of the forward intermediate relay KA1 coil, the lower end of the forward time relay KT1 coil, the lower end of the reverse intermediate relay KA2 coil, the lower end of the reverse time relay KT2 coil, the lower end of the reversing intermediate relay KA3 coil, the lower end of the forward contactor KM1 coil, the lower end of the forward indicator light HD1, the lower end of the reverse contactor KM2 coil, and the lower end of the reverse indicator light HD2 are connected in parallel, and then the normally closed contact of the series thermal relay FR is connected to one end of the bipolar circuit breaker QF2; the other end of the bipolar circuit breaker QF2 is connected to the secondary line power supply port B.

[0013] The present invention uses a button to control the interval forward and reverse switching of the motor, which further develops the forward and reverse circuit of the motor. The forward and reverse rotation of the motor can be controlled more flexibly and conveniently, and a protection circuit with interlocking, double interlocking and automatic power-off functions is added to the circuit, which can realize low voltage and long-distance frequent control.

[0014] The circuit is simple, easy to operate, reliable in operation, and realizes multiple protections. It will not cause mechanical accidents by pressing the wrong forward and reverse buttons, nor will it cause power short circuit accidents, thus ensuring the normal operation of the production line equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The invention discloses a single-button forward / reverse automatic stop control circuit diagram. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the figures and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0017] Depend on Figure 1 It can be seen that the single-button forward and reverse automatic stop control circuit of this embodiment includes a secondary line power port A and a power port B of an external 220V AC power supply, and also includes a forward contactor KM1, a reverse contactor KM2, a forward intermediate relay KA1, a reverse intermediate relay KA2, a reversing intermediate relay KA3, a thermal relay FR, a forward time relay KT1, a reverse time relay KT2, a bipolar circuit breaker QF1 and QF2, a button SB, and a forward indicator light HD1 and a reverse indicator light HD2.

[0018] In this embodiment, the contacts involved in the control of the forward intermediate relay KA1 include: a normally closed contact of the forward intermediate relay, a normally open contact KA1-1 of the forward intermediate relay, and a normally open contact KA1-2 of the forward intermediate relay.

[0019] The contacts involved in the control of the reversing intermediate relay KA2 include: a normally open contact of the reversing intermediate relay, a normally closed contact KA2-1 of the reversing intermediate relay, and a normally closed contact KA2-2 of the reversing intermediate relay.

[0020] The contacts involved in the control of the commutation intermediate relay KA3 include: a commutation intermediate relay normally closed contact, a commutation intermediate relay normally open contact KA3-1, and a commutation intermediate relay normally open contact KA3-2.

[0021] After the secondary line power supply port A is connected to the bipolar circuit breaker QF1, it is connected in parallel with the upper end of the button SB, the upper end of the normally open contact KA1-2 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-2 of the reversing intermediate relay KA3, the upper end of the delayed disconnection normally open contact of the forward time relay KT1, and the upper end of the delayed disconnection normally open contact of the reverse time relay KT2.

[0022] The lower end of the button SB is connected in parallel with the upper end of the normally closed contact of the reversing intermediate relay KA3, the upper end of the normally open contact KA1-1 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-1 of the reversing intermediate relay KA3, and the upper end of the normally open contact of the reversing intermediate relay KA2.

[0023] After the lower end of the normally closed contact of the reversing intermediate relay KA3 is connected in parallel with the lower end of the normally open contact KA1-1 of the forward intermediate relay KA1, the normally closed contact KA2-1 of the reversing intermediate relay is connected in series, and then connected in parallel with the upper end of the coil of the forward intermediate relay KA1 and the upper end of the coil of the forward time relay KT1.

[0024] After the lower end of the normally open contact KA3-1 of the reversing intermediate relay and the lower end of the normally open contact of the reversing intermediate relay KA2 are connected in parallel, the normally closed contact of the forward intermediate relay KA1 is connected in series, and then connected in parallel with the upper end of the coil of the reversing intermediate relay KA2 and the upper end of the coil of the reversing time relay KT2.

[0025] The lower end of the normally open contact KA1-2 of the forward intermediate relay and the lower end of the normally open contact KA3-2 of the reversing intermediate relay are connected in parallel, and then the normally closed contact KA2-2 of the reversing intermediate relay is connected in series, and connected to the upper end of the coil of the reversing intermediate relay KA3.

[0026] The forward time relay KT1 delays disconnecting the lower end of the normally open contact connected in series with the normally closed contact of the reversing contactor KM2, and then is connected in parallel with the upper end of the coil of the forward contactor KM1 and the upper end of the forward indicator light HD1.

[0027] The reversing time relay KT2 delays disconnecting the lower end of the normally open contact in series with the normally closed contact of the forward contactor KM1, and then is connected in parallel with the upper end of the coil of the reversing contactor KM2 and the upper end of the reversing indicator light HD2.

[0028] The lower end of the forward intermediate relay KA1 coil, the lower end of the forward time relay KT1 coil, the lower end of the reverse intermediate relay KA2 coil, the lower end of the reverse time relay KT2 coil, the lower end of the reversing intermediate relay KA3 coil, the lower end of the forward contactor KM1 coil, the lower end of the forward indicator light HD1, the lower end of the reverse contactor KM2 coil, and the lower end of the reverse indicator light HD2 are connected in parallel, and then the normally closed contact of the series thermal relay FR is connected to one end of the bipolar circuit breaker QF2; the other end of the bipolar circuit breaker QF2 is connected to the secondary line power supply port B.

[0029] The present invention can control the forward and reverse rotation of the motor in a single-button operation mode, and is particularly suitable for application scenarios where frequent forward and reverse rotation of the motor is required. When the button SB is pressed, the circuit is connected and the motor works; when the button SB is released, the circuit is disconnected and the motor stops.

[0030] The control steps of the present invention are described in detail below:

[0031] In this embodiment, when the forward rotation is started with automatic stop, first manually close the bipolar circuit breakers QF1 and QF2, then press the button SB, and the coil of the forward rotation intermediate relay KA1 and the coil of the forward rotation time relay KT1 are energized at the same time. The normally open contact KA1-1 of the forward rotation intermediate relay KA1 is closed and self-locked, and at the same time, the interlock disconnects the loop of the reverse rotation intermediate relay KA2 coil and the reverse rotation time relay KT2 coil. The normally open contact of the forward rotation time relay KT1 is closed after the delay disconnection, and the coil of the forward rotation contactor KM1 is energized and actuated, the forward rotation main circuit is connected, and the motor starts to rotate forward, and the forward rotation indicator HD1 lights up at the same time.

[0032] In addition, the other normally open contact KA1-2 of the forward intermediate relay KA1 is closed, the coil of the reversing intermediate relay KA3 is energized and actuated, and the normally open contact KA3-2 of the reversing intermediate relay KA3 is closed and self-locked. The normally closed contact of the reversing intermediate relay KA3 is pre-opened, and the coil of the forward intermediate relay KA1 and the coil of the forward time relay KT1 are looped; the other normally open contact KA3-1 of the reversing intermediate relay KA3 is pre-connected, and the coil of the reversing intermediate relay KA2 and the coil of the reversing time relay KT2 are looped. Prepare for the next reversal.

[0033] At this time, release the button SB, the coil of the forward intermediate relay KA1 and the coil of the forward time relay KT1 lose power, and all their contacts return to their original state. The forward time relay KT1 delays disconnecting the contacts, and delays disconnecting the forward contactor KM1 coil circuit. The forward main circuit is disconnected, and the motor stops forward rotation.

[0034] In this embodiment, when the reverse automatic stop is started, the other normally open contact KA3-1 of the reversing intermediate relay KA3 is pre-connected, and the coil of the reversing intermediate relay KA2 and the coil of the reversing time relay KT2 are energized. At this time, the button SB is pressed, and the coil of the reversing intermediate relay KA2 and the coil of the reversing time relay KT2 are energized at the same time. The normally open contact of the reversing intermediate relay KA2 closes and self-locks, and at the same time, the interlock disconnects the coil of the forward intermediate relay KA1 and the coil of the forward time relay KT2. The normally open contact of the reversing time relay KT2 is closed after the delay disconnection, and the coil of the reversing contactor KM2 is energized and actuated, the reversing main circuit is connected, and the motor starts to reverse, and the reversing indicator HD2 lights up at the same time.

[0035] In addition, the normally closed contact KA2-2 of the reversing intermediate relay KA2 is disconnected, and the coil of the commutating intermediate relay KA3 is de-energized. The normally open contact KA3-1 of the commutating intermediate relay KA3 is pre-disconnected, and the coil of the reversing intermediate relay KA2 and the reversing time relay KT2 are looped; preparing for the next forward rotation.

[0036] At this time, release the button SB, the coil of the reversing intermediate relay KA2 and the coil of the reversing time relay KT2 lose power, and all their contacts return to their original state. The reversing time relay KT2 delays disconnecting the contacts, and delays disconnecting the reversing contactor KM2 coil circuit. The reversing main circuit is disconnected, and the motor stops reversing.

[0037] Typical application scenario 1

[0038] The present invention is applicable to the forward and reverse rotation of the mixer, and its specific working process includes:

[0039] 1. Preset the delay time of the forward time relay KT1 and the reverse time relay KT2 according to the application requirements. The power of the mixer is provided by the electric motor.

[0040] 2. Click and release button SB, the motor will rotate forward, and the working time is determined by the forward time relay KT1.

[0041] 3. After the forward operation is completed, click and release the button SB. According to the design of the control circuit, the motor automatically switches to the reverse mode, and the working time is determined by the reverse time relay KT2.

[0042] Typical application scenario 2

[0043] The present invention is applicable to application scenarios where forward and reverse rotation are frequently switched, and its specific workflow includes:

[0044] 1. Preset the delay time of the forward time relay KT1 and the reverse time relay KT2 as needed.

[0045] 2. Press and hold button SB, the motor rotates forward, and the working time is determined by the pressure time of button SB.

[0046] 3. Release button SB. After the delay of forward rotation time relay KT1 is reached, the motor stops.

[0047] 4. Press and hold button SB, the motor will automatically switch to reverse mode. The reverse working time is also determined by the pressure time of button SB.

[0048] 5. Release button SB. After the delay of reversal time relay KT2 is reached, the motor stops.

[0049] In this application scenario, the delay time of the forward time relay KT1 and the reverse time relay KT2 can be preset to 0. At this time, the forward and reverse rotation time of the motor is completely controlled by the operator.

[0050] The circuit is simple, easy to operate, reliable in operation, and realizes multiple protections. It will not cause mechanical accidents by pressing the wrong forward and reverse buttons, nor will it cause power short circuit accidents, thus ensuring the normal operation of the equipment.

[0051] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A single-button forward and reverse automatic stop control circuit, including a secondary line power port A and a power port B connected to an external 220V AC power supply, characterized in that: It also includes a forward contactor KM1, a reverse contactor KM2, a forward intermediate relay KA1, a reverse intermediate relay KA2, a reversing intermediate relay KA3, a thermal relay FR, a forward time relay KT1, a reverse time relay KT2, a bipolar circuit breaker QF1 and QF2, a button SB, and a forward indicator light HD1 and a reverse indicator light HD2; After the secondary line power supply port A is connected to the bipolar circuit breaker QF1, it is connected in parallel with the upper end of the button SB, the upper end of the normally open contact KA1-2 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-2 of the reversing intermediate relay KA3, the upper end of the delayed disconnection normally open contact of the forward time relay KT1, and the upper end of the delayed disconnection normally open contact of the reverse time relay KT2; The lower end of the button SB is connected in parallel with the upper end of the normally closed contact of the reversing intermediate relay KA3, the upper end of the normally open contact KA1-1 of the forward intermediate relay KA1, the upper end of the normally open contact KA3-1 of the reversing intermediate relay KA3, and the upper end of the normally open contact of the reversing intermediate relay KA2; After the lower end of the normally closed contact of the reversing intermediate relay KA3 is connected in parallel with the lower end of the normally open contact KA1-1 of the forward intermediate relay KA1, the normally closed contact KA2-1 of the reversing intermediate relay is connected in series, and then connected in parallel with the upper end of the coil of the forward intermediate relay KA1 and the upper end of the coil of the forward time relay KT1; After the lower end of the normally open contact KA3-1 of the reversing intermediate relay and the lower end of the normally open contact of the reversing intermediate relay KA2 are connected in parallel, the normally closed contact of the forward intermediate relay KA1 is connected in series, and then connected in parallel with the upper end of the coil of the reversing intermediate relay KA2 and the upper end of the coil of the reversing time relay KT2; The lower end of the normally open contact KA1-2 of the forward intermediate relay and the lower end of the normally open contact KA3-2 of the reversing intermediate relay are connected in parallel, and then connected in series with the upper end of the normally closed contact KA2-2 of the reversing intermediate relay. The lower end of the normally closed contact KA2-2 of the reversing intermediate relay is connected to the upper end of the coil of the reversing intermediate relay KA3; The forward time relay KT1 delays disconnecting the lower end of the normally open contact in series with the normally closed contact of the reverse contactor KM2, and then is connected in parallel with the upper end of the coil of the forward contactor KM1 and the upper end of the forward indicator light HD1; The reverse time relay KT2 delays disconnection of the normally open contact lower end connected in series with the normally closed contact of the forward contactor KM1, and then connected in parallel with the upper end of the reverse contactor KM2 coil and the upper end of the reverse indicator HD2; The lower end of the forward intermediate relay KA1 coil, the lower end of the forward time relay KT1 coil, the lower end of the reverse intermediate relay KA2 coil, the lower end of the reverse time relay KT2 coil, the lower end of the reversing intermediate relay KA3 coil, the lower end of the forward contactor KM1 coil, the lower end of the forward indicator light HD1, the lower end of the reverse contactor KM2 coil, and the lower end of the reverse indicator light HD2 are connected in parallel, and then the normally closed contact of the series thermal relay FR is connected to one end of the bipolar circuit breaker QF2; the other end of the bipolar circuit breaker QF2 is connected to the secondary line power supply port B.

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