Lithology density pusher circuit

Abstract

This utility model discloses a lithological density pusher circuit, including a bridge rectifier D, relays K1 and K2, a travel limit switch K, a pusher motor, and a power supply unit. A freewheeling diode D8 is connected in parallel at the coil winding port of relay K1, and similarly, a freewheeling diode D9 is connected in parallel at the coil winding port of relay K2. Both freewheeling diodes D8 and D9 are 1N5408 diodes, which can further reduce the risk of breakdown and destruction by sudden current, thereby protecting the power supply unit and improving the service life of the pusher circuit.

Description

Technical Field

[0001] This utility model belongs to the field of lithology density logging technology, specifically relating to a lithology density pusher circuit. Background Technology

[0002] Density logging, also known as gamma-gamma logging, is an important logging method for determining lithology and rock density. Lithology density logging uses Cs-137 as a gamma source to release gamma rays with an energy of 0.66 MeV. The radioactive isotope gamma source radiates gamma rays into the formation, and the intensity of the gamma rays after scattering and absorption by the formation is measured by a detector to determine the density and lithology of the rock.

[0003] A freewheeling diode, sometimes called a flywheel diode or snubber diode, is a diode used with inductive loads. When the current in an inductive load changes suddenly or decreases, a sudden voltage surge occurs across the inductor, potentially damaging other components. When used with a freewheeling diode, the current changes more smoothly, preventing voltage spikes. Freewheeling diodes are often used with energy storage components to prevent sudden voltage and current changes and provide a path for the load. The inductor can then supply a continuous current to the load, preventing sudden current changes and smoothing the current flow. In switching power supplies, a freewheeling circuit consisting of a diode and a resistor connected in series is connected in parallel with the primary winding of the transformer. When the switching transistor is turned off, the freewheeling circuit releases the energy stored in the transformer coil, preventing excessive induced voltage that could damage the switching transistor. Generally, a fast recovery diode or a Schottky diode is sufficient to dissipate the reverse electromotive force generated by the coil through current. It can be seen that the "freewheeling diode" is not a substantial component; it merely plays a role in the circuit. Frequent failure of the freewheeling diode leads to sudden changes in the branch load current. The sudden current is large, which breaks down the Zener diode of the power supply unit, causing the push-pull circuit relay to fail to engage and complete the push-pull operation. This results in abnormal data output from the lithology density PHA plate, incorrect energy spectrum analysis values, and ultimately, density logging failure.

[0004] Chinese utility model patent (authorization announcement number CN205936580U) discloses a pushing device for a lithological density pusher, including a pushing box and a pushing circuit disposed inside the pushing box. The surface of the pushing box is provided with a power switch, a push-and-retract switch, a power indicator light, a plug for connecting the lithological density pusher, and a power socket for connecting to a power source. The top of the pushing box is provided with a handle for easy carrying. The pushing circuit includes a transformer T1 and a rectifier chip U1. One end of the auxiliary winding of the transformer T1 is connected to the first pin of the plug J1, and the other end of the auxiliary winding of the transformer T1 is connected to the fourth pin of the plug J1.

[0005] Chinese utility model patent (authorization announcement number CN201568052U) discloses a pushing device for a lithological density pusher. Transformer T1 transforms the input 220V AC and outputs two sets of voltages: 180V AC and 12V AC. The 12V AC is rectified, filtered, and regulated to obtain 7.5V DC. Transformer T2 transforms the input 220V AC and outputs three sets of pushing voltages: 90V, 110V, and 130V. The three sets of pushing voltages are connected to a pushing selection voltage switch.

[0006] Neither of the two published patents mentioned above analyzed the technical problem of density logging failure caused by a malfunction in the lithology density pusher itself. Summary of the Invention

[0007] The purpose of this invention is to solve the above-mentioned technical problems and provide a rock density pusher circuit that can protect the power supply unit.

[0008] To achieve the above objectives, this utility model provides a lithological density pusher circuit, including a bridge rectifier D, relays K1 and K2, a travel limit switch K, a pusher motor, and a power supply unit; a freewheeling diode D8 is connected in parallel at the coil winding port of relay K1, and a freewheeling diode D9 is connected in parallel at the coil winding port of relay K2. Both freewheeling diodes D8 and D9 are 1N5408 diodes.

[0009] Furthermore, the two output terminals of the bridge rectifier D are connected to the two input terminals, pins 3 and 6, of the relay K1, respectively, and the two output terminals, pins 4 and 7, of the relay K1 are connected to the two input terminals, pins 3 and 6, of the relay K2, respectively.

[0010] Furthermore, the voltage output terminal of the power supply unit is connected to pin 1 of the coil windings of relays K1 and K2, respectively, and pin 2 of the coil windings of relays K1 and K2 are both control terminals.

[0011] Furthermore, the operating voltage of one output terminal, pin 4 of the relay K2, is boosted sequentially through resistor R5, parallel capacitor C6, and resistor R6.

[0012] Furthermore, one output terminal, pin 4 of the relay K2, is connected in sequence to the push motor via a diode and a travel limit switch K. The push motor is connected in parallel and in series with a resistor R7 and a capacitor C7.

[0013] Furthermore, the two output terminals of the relay K2, pins 5 and 7, are both connected to capacitor C6, and resistor R6 is connected to capacitor C7.

[0014] Furthermore, pin 8 of the relay K2 is connected to pin 4 of the relay K2.

[0015] Furthermore, the diode is model number 1N1348.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model uses a 1N5408 diode, which can further reduce the risk of being broken down or destroyed by sudden current, thereby achieving the function of protecting the power supply unit and improving the service life of the push circuit. Attached Figure Description

[0017] Figure 1 This is a circuit diagram of the lithology density pusher of this utility model. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 The lithology density pusher circuit shown includes a bridge rectifier D, relays K1 and K2, a travel limit switch K, a pusher motor, and a power supply unit. The two output terminals of the bridge rectifier D are connected to pins 3 and 6 of the two input terminals of relay K1, respectively. The two output terminals of relay K1, pins 4 and 7, are connected to pins 3 and 6 of the two input terminals of relay K2, respectively. The voltage output terminal of the power supply unit is connected to pin 1 of the coil windings of relays K1 and K2, thereby supplying power to relays K1 and K2. Pins 2 of the coil windings of relays K1 and K2 are both control terminals. A freewheeling diode D8 is connected in parallel at the coil winding port of relay K1, and similarly, a freewheeling diode D9 is connected in parallel at the coil winding port of relay K2. Both freewheeling diodes D8 and D9 are 1N5408 diodes. One output terminal, pin 4 of relay K2, is connected to the operating voltage via resistor R5, parallel capacitor C6, and resistor R6 in sequence. The other output terminal is connected to the push motor via diode, limit switch, and parallel resistor R7 and capacitor C7 in series. Both output terminals, pins 5 and 7 of relay K2, are connected to capacitor C6, and resistor R6 is connected to capacitor C7. Output terminal 8 of relay K2 is connected to output terminal 4 of relay K2.

[0020] When neither relay K1 nor relay K2 receives a control signal from the control terminal, pins 3 and 5 of relay K1 and pins 6 and 8 of relay K1 are engaged, and pins 3 and 5, and pins 6 and 8 of relay K2 are engaged. Both relays K1 and K2 are in a floating state. When relays K1 and K2 receive a control signal, the +24V power supply circuit of the relay coil winding is connected, and the relays are engaged to switch positions. Then, pins 3 and 4, and pins 6 and 7 of relay K1 are engaged, and pins 3 and 4, and pins 6 and 7 of relay K2 are engaged.

[0021] Depend on Figure 1 It can be seen that the connection of relay K1 provides 110V to the next stage circuit. Therefore, the function of relay K1 is to connect and disconnect 110V. Regardless of whether relay K2 receives a control signal, as long as relay K1 connects to the 110V DC power supply, relay K2 will complete the forward and reverse switching of the push motor.

[0022] The voltage coming into pin 3 of relay K2 is +110V. R5 and C6R6 boost the operating voltage to 110V to ensure it can drive the load. After the voltage is boosted by the bootstrap circuit of R5C6R6, it passes through diode D7, the travel limit switch, and then the push motor to complete the forward rotation of the push motor.

[0023] If the motor needs to be reversed, relay K1 remains on, relay K2 shifts gears, and pins 3 and 5 of relay K2, and pins 6 and 8 of relay K2 are engaged. The input +110V voltage is then sent from pin 3 of relay K2 to pin 5 → R5R6C6 → R7C7 unit → motor → limit switch → diode D6 → pin 8 of relay K2 → pin 6 → 110V GND, thus achieving reverse rotation.

[0024] The aforementioned diodes D6 and D7 are model number 1N1348.

[0025] A faulty freewheeling diode connected in parallel with the relay coil winding caused a sudden change in the branch load current. This large sudden current damaged the Zener diode in the power supply unit, preventing the push-to-close circuit relay from engaging and completing the push-to-close operation. Therefore, this invention uses a 1N5408 diode for protection. Because the 1N5408 diode has a non-repetitive peak forward current I... FSM With a current rating of up to 200A, the 1N5408 diode has a higher current tolerance, which can further reduce the risk of being broken down or destroyed by sudden current surges, thereby protecting the power supply unit.

Claims

1. A lithological density pusher circuit, comprising a bridge rectifier D, relays K1 and K2, a travel limit switch K, a pusher motor, and a power supply unit; characterized in that: A freewheeling diode D8 is connected in parallel at the coil winding port of relay K1, and a freewheeling diode D9 is connected in parallel at the coil winding port of relay K2. Both freewheeling diodes D8 and D9 are 1N5408 diodes.

2. The lithology density pusher circuit according to claim 1, characterized in that: The two output terminals of the bridge rectifier D are connected to the two input terminals, pins 3 and 6, of relay K1, respectively. The two output terminals, pins 4 and 7, of relay K1 are connected to the two input terminals, pins 3 and 6, of relay K2, respectively.

3. The lithology density pusher circuit according to claim 1, characterized in that: The voltage output terminal of the power supply unit is connected to pin 1 of the coil windings of relays K1 and K2, respectively. Pin 2 of the coil windings of relays K1 and K2 are both control terminals.

4. The lithology density pusher circuit according to claim 2, characterized in that: One output terminal, pin 4 of the relay K2, has its operating voltage boosted sequentially via resistor R5, parallel capacitor C6, and resistor R6.

5. The lithology density pusher circuit according to claim 4, characterized in that: One output terminal, pin 4 of the relay K2, is connected in sequence to a diode, a travel limit switch K, and a push motor. The push motor is connected in parallel and in series with a resistor R7 and a capacitor C7.

6. The lithology density pusher circuit according to claim 4, characterized in that: The two output terminals of relay K2, pins 5 and 7, are both connected to capacitor C6, and resistor R6 is connected to capacitor C7.

7. The lithology density pusher circuit according to claim 4, characterized in that: The output pin 8 of relay K2 is connected to the output pin 4 of relay K2.

8. The lithology density pusher circuit according to claim 5, characterized in that: The diode is model number 1N1348.

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