Remote control automatic door circuit b

This kind of voice control circuit is used to control the automatic opening and closing of the door, and the effect is better. Whenever an incoming or outgoing vehicle approaches the gate, the driver presses
the speaker and the gate automatically opens. When the vehicle moves behind, the gate automatically closes.
    The control device consists of two parts: electronic circuit and electrical control circuit, as shown in the figure.
    (1) The sound control principle of door opening control uses the loudspeaker to receive the vehicle loudspeaker sound signal (Yl and Y2 in Figure 18-3.6a,
one installed inside and outside the door), and converts it into a voltage signal through the AC amplification circuit (VT1, VT2 , VT3, VT4). After amplification, half-wave
rectification by diode VD1 and capacitor filtering, a negative voltage is obtained on the base of transistor VT5. VT5 and VT6 form a Schmitt trigger. When there is no signal
, VT5 is cut off, VT6 is on, and VT7 is off. When the signal voltage acts on the base of VT5 and reaches the threshold voltage, the flip-flop flips,
turning VT5 on, VT6 off, the output stage VT7 changes from off to on, relay J is closed, and the contact in Figure 18-36b Point J is connected,
driving contactor KM1, normally closed contact KM1 is disconnected, completing the interlinking action, powering the motor to rotate forward, and controlling the mechanical part of the door to open the door.
    (2) The motor stops to control the mechanical part of the door. The motor drives the transmission mechanisms such as gears, racks, gearboxes and driving shafts, and then
pulls the door through the belt pulley and wire rope. After the door is opened, there is a horizontal iron on the left side of the door that touches the travel switch XWK1 , causing contactor KM1 to lose power and the motor
to stop.
    (3) Delayed door closing control: After the motor stops, the delay relay sJ is turned on, and after a delay of 7s (measure the door opening lOs. The vehicle can
enter and exit smoothly). Its contacts are connected to contactor KM2 to cause the motor to reversely rotate and close the door. When the door is closed, there is also a horizontal iron on the right side of the door that touches the travel switch
XWK2, causing the contactor KM2 to lose power and the engine to stop, thereby completing the opening and closing action.
    (4) Manual operation controls the normal access of people. Opening and closing the door can be operated by buttons. When opening the door, press SA1 when inside n and
press SA2 when outside the door, which can energize the contactor KM1, causing the motor to rotate forward to open the door and close the door. The process is the same as above. If there are many people entering and exiting at the same time and the 7s delay
is not enough, you can hold down SB to prevent the door from closing automatically. After people have finished entering and exiting, release SB to energize contactor KM2 and reverse the motor to close
the door. If when SB is turned on, XWK1 connected to the delay relay coil SJ has been disconnected by the armature (that is, the contact sJ is disconnected). You can
press SA3 by hand to energize contactor KM2 to close the door.
    The thermal relay R in the figure plays the role of overload protection. In order to prevent the car from being pinched, a micro switch is installed next to the door. When a car is pinched, touch the micro
switch and the door will open immediately; the KMI control indicator light HL. KM2 controls the electric bell HA, so the light is on when the door is opened and the door is closed to ensure safety.