CN210224932U

CN210224932U - Energy limiting circuit

Info

Publication number: CN210224932U
Application number: CN201921573806.4U
Authority: CN
Inventors: Deqiang Guo; 郭德强; Xianwen Yuan; 袁显文; Fangjuan Hao; 郝芳娟; Xiaojuan Feng; 冯小娟; Liucheng Nie; 聂留城; Dongdong Liu; 刘冬冬; Na Chen; 陈娜; Yaping Lyu; 吕亚平
Original assignee: Star Polytron Technologies Inc
Current assignee: Star Polytron Technologies Inc
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2020-03-31
Anticipated expiration: 2029-09-20

Abstract

The utility model discloses an energy-limiting circuit, this energy-limiting circuit are including the voltage stabilizing circuit who is used for stabilizing input voltage, still including the signal amplification circuit who is used for gathering and enlargies energy-limiting circuit negative pole output end signal, be used for carrying out the signal comparison circuit of comparison to the signal after signal amplification circuit enlargies to and be used for controlling the switch circuit of energy-limiting circuit input end break-make electricity according to signal comparison circuit's feedback signal. This limit can circuit is through gathering, enlargiing, comparing the signal of telecommunication on the unmanned vending machine working circuit to feed back switch circuit, effectively improved this limit can circuit's sensitivity, improved this limit can circuit's explosion-proof grade, make unmanned vending machine not only can be used to ordinary occasion, still can be used to the place that has inflammable and explosive material such as filling station.

Description

Energy limiting circuit

Technical Field

The utility model relates to a safety circuit technical field, concretely relates to limit can circuit.

Background

In explosion-proof occasions such as gas stations and gas filling stations, the electrical appliances required to be used need to have explosion-proof performance, that is, the circuits of the electrical equipment need to be designed into intrinsic safety circuits.

The unmanned vending machine is vending equipment commonly found in areas such as schools, restaurants and office building passages, and is convenient for customers to shop and simultaneously reduces the selling cost of merchants.

Chinese patent publication No. CN104184107A describes an intrinsically safe energy limiting circuit and a lighting device, in which the intrinsically safe energy limiting circuit is low in sensitivity and explosion-proof level because a large signal abnormality is required at an output terminal to be able to respond, and a weak current circuit such as a motor control circuit and a signal communication circuit is generally provided in an unmanned vending machine, and an energy limiting circuit is required to have high sensitivity.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a limit can circuit, it is low to solve limit can circuit sensitivity among the prior art, technical problem that explosion-proof level is low.

In order to solve the technical problem, the utility model discloses a technical scheme:

the energy limiting circuit comprises a voltage stabilizing circuit used for stabilizing input voltage, a signal amplifying circuit used for collecting and amplifying signals at the cathode output end of the energy limiting circuit, a signal comparing circuit used for comparing the signals amplified by the signal amplifying circuit, and a switch circuit used for controlling the on-off state of the input end of the energy limiting circuit according to feedback signals of the signal comparing circuit.

Preferably, the voltage stabilizing circuit comprises a first diode D1 and a second diode D2 which are connected in parallel between the anode and the cathode of the input end of the energy limiting circuit, and the first diode D1 and the second diode D2 are voltage stabilizing diodes.

Preferably, the switching circuit comprises a MOS transistor Q1, a thyristor Q2 and a triode Q3, wherein the source of the MOS transistor Q1 is connected with the positive electrode of the input end of the energy limiting circuit, and the drain of the MOS transistor Q1 is connected with the positive electrode of the output end of the energy limiting circuit; the control electrode of the controllable silicon Q2 is connected with the output end of the signal comparison circuit, the controllable silicon Q2 is electrically connected with the triode Q3 to control the on-off of the triode Q3, and the triode Q3 is electrically connected with the MOS tube Q1 to control the on-off of the MOS tube Q1.

Preferably, the signal comparison circuit comprises a first operational amplifier U1A, and the first operational amplifier U1A receives the output signal of the signal amplification circuit for comparison and outputs a signal to control the switch circuit.

Preferably, the signal amplifying circuit includes a second operational amplifier U1B, the second operational amplifier U1B is configured to collect and amplify the negative signal at the output end of the energy limiting circuit, and the second operational amplifier U1B transmits the amplified signal to the signal comparing circuit.

Preferably, a third diode D3 is provided between the switch circuit and the signal comparison circuit, and the cathode of the third diode D3 is connected to the switch circuit and the anode is connected to the signal comparison circuit.

Preferably, a fourth diode D4 is provided between the signal comparison circuit and the signal amplification circuit, and a cathode of the fourth diode D4 is connected to the signal comparison circuit and an anode thereof is connected to the signal amplification circuit.

The utility model has the advantages of:

1. the utility model provides a limit can circuit gathers, enlargies, compares through the signal of telecommunication with on the unmanned vending machine working circuit to feed back switch circuit, effectively improved this limit can circuit's sensitivity, improved this limit can circuit's explosion-proof grade.

2. The utility model provides a limit can circuit can be for the working circuit power supply of unmanned vending machine, can in time effectively cut off the unstable signal of telecommunication on the unmanned vending machine working circuit, keeps working circuit current stable, prevents to expose each electrical components outside and produces the spark, and the working circuit of unmanned vending machine can reach this ampere of rank for unmanned vending machine not only can be used to ordinary occasion, still can be used to the place that has inflammable and explosive material such as filling station.

Drawings

Fig. 1 is a schematic circuit diagram of an embodiment of an energy limiting circuit of the present invention;

fig. 2 is a schematic circuit diagram of another embodiment of the energy limiting circuit of the present invention.

In the drawings, each reference numeral means: a voltage stabilizing circuit 11, a switch circuit 12, a signal comparison circuit 13 and a signal amplification circuit 14.

Detailed Description

The following embodiments are only intended to illustrate the present invention in detail, and do not limit the scope of the present invention in any way.

Example 1:

an energy limiting circuit is shown in fig. 1.

As shown in fig. 1, the embodiment of the present invention provides an energy limiting circuit, wherein VCC is connected to the positive terminal of the output terminal of the 220VAC-5VDC power module, the 220VAC-5VDC power module converts the commercial power into 5V dc power, and the output terminal of the energy limiting circuit supplies power to the electric equipment, so as to prevent the electric equipment from generating sparks due to short-circuit and other faults.

The energy limiting circuit comprises a voltage stabilizing circuit 11 for stabilizing input voltage, a signal amplifying circuit 14 for collecting and amplifying ib-GND signals at the cathode output end of the energy limiting circuit, a signal comparing circuit 13 for comparing signals amplified by the signal amplifying circuit 14, and a switch circuit 12 for controlling the power-on and power-off of a VCC at the input end of the energy limiting circuit according to a feedback signal of the signal comparing circuit 13.

The voltage stabilizing circuit 11 includes a first diode D1 and a second diode D2 connected in parallel between the anode VCC and the cathode GND of the input terminal of the energy limiting circuit, and the first diode D1 and the second diode D2 are zener diodes.

The signal amplification circuit comprises a second operational amplifier U1B, the inverting input end of the second operational amplifier U1B is connected with an eleventh resistor R11 in series and then connected with the negative pole GND of the input end of the energy limiting circuit, and a tenth resistor R10 is connected between the inverting input end and the output end of the second operational amplifier U1B in series; the non-inverting input end of the second operational amplifier U1B is connected in series with a twelfth resistor R12 and then connected with the output end cathode ib-GND of the energy limiting circuit, the non-inverting input end of the second operational amplifier U1B is further connected in series with a fourth capacitor C4 and a thirteenth resistor R13 and then connected with the output end cathode ib-GND of the energy limiting circuit, the common end, connected with the fourth capacitor C4 and the thirteenth resistor R13, of the input end cathode GND of the energy limiting circuit, and the fourth capacitor C4 plays a role in filtering.

The working principle of the signal amplifying circuit is as follows: when the power output terminal is abnormal, for example, when a short circuit occurs between the positive electrode ib-VCC and the negative electrode ib-GND of the power output terminal, a large current will flow through the twelfth resistor R12, a large voltage will be generated across the twelfth resistor R12, a voltage signal is provided at the non-inverting input terminal of the second operational amplifier U1B, and the voltage signal of the second operational amplifier U1B is amplified and then output to the signal comparison circuit through the output terminal.

The signal comparison circuit comprises a first operational amplifier U1A, the inverting input end of the first operational amplifier U1A is connected with a seventh resistor R7 in series and then is connected with the negative pole GND of the input end of the energy limiting circuit, the inverting input end of the first operational amplifier U1A is connected with a fifth resistor R5 and a sixth resistor R6 in series and then is connected with the positive pole end of the first operational amplifier, and the terminals connected with the fifth resistor R5 and the sixth resistor R6 are connected with the positive pole VCC of the input end of the energy limiting circuit; the non-inverting input end of the first operational amplifier U1A is connected in series with a ninth resistor R9 and a fourth diode D4 and then is connected with the output end of the second operational amplifier U1B, the common terminal of the ninth resistor R9 and the fourth diode D4 is also connected in series with a third capacitor C3 and then is connected with the negative pole GND of the input end of the energy limiting circuit, the fourth diode D4 can protect the output end of the second operational amplifier U1B from being impacted by high pulse voltage, and the third capacitor C3 plays a role in filtering; the negative electrode of the first operational amplifier U1A is connected with the negative electrode GND of the input end of the energy limiting circuit, and the positive electrode is connected with the positive electrode VCC of the input end of the energy limiting circuit; the output terminal of the first operational amplifier U1A is also connected to one terminal of the third diode D3, and the third diode D3 protects the output terminal of the first operational amplifier U1A from high pulse voltages.

The working principle of the signal comparison circuit is as follows: when the non-inverting input of the first operational amplifier U1A receives a signal from the signal amplification circuit, the voltage signal of the second operational amplifier U1B is compared with the signal at the inverting input of the first operational amplifier U1A, and if the difference between the two signals exceeds a certain threshold, the output of the first operational amplifier U1A outputs a signal that controls the operation of the switching circuit.

The switching circuit comprises an MOS tube Q1, a controlled silicon Q2 and a triode Q3, the controlled silicon Q2 is a variable capacitor, the MOS tube Q1 is a P-channel MOS tube, the source electrode of the MOS tube Q1 is connected with the anode VCC of the input end of the energy limiting circuit, and the drain electrode of the MOS tube Q1 is connected with the anode ib-VCC of the output end of the energy limiting circuit; the collector of the triode Q3 is connected with the anode VCC of the input end of the energy limiting circuit, the base of the triode Q3 is connected with the anode VCC of the input end of the energy limiting circuit through a first resistor R1, the emitter of the triode Q3 is connected with the grid of the MOS tube Q1 through a third resistor R3, and the grid of the MOS tube Q1 is connected with the cathode GNDGND of the input end of the energy limiting circuit after being connected with a fourth resistor R4 and a first capacitor C1 in parallel; the positive pole of silicon controlled rectifier Q2 connects triode Q3's base through second resistance R2, silicon controlled rectifier Q2's negative pole meets the input negative pole GND of limit ability circuit, and silicon controlled rectifier Q2's control pole meets the input negative pole GND of limit ability circuit through second electric capacity C2, second electric capacity C2 is as energy storage capacitor, can not automatic recovery after guaranteeing the circuit break down, need the outage just can recover, prevent circuit fault hiccup. The first fuse F1 is arranged at the anode VCC of the input end of the energy limiting circuit, and further plays a role in preventing the current in the circuit from being overlarge.

The switching circuit 12 operates as follows: when the output end of the energy limiting circuit is abnormal, the signal comparison circuit 13 outputs a signal to the control end of the controlled silicon Q2, the terminal 1 and the terminal 3 of the controlled silicon Q2 are conducted, the current between the base electrode and the emitting electrode of the triode Q3 is increased, the triode Q3 is conducted, the grid electrode of the MOS tube Q1 generates high voltage, the source electrode and the drain electrode of the MOS tube Q1 are cut off, and the output end of the energy limiting circuit is prevented from being continuously supplied with power.

The utility model provides a limit can circuit can be for the working circuit power supply of unmanned vending machine, can in time effectively cut off the unstable signal of telecommunication on the unmanned vending machine working circuit, keeps working circuit current stable, prevents to expose each electrical components outside and produces the spark, and the working circuit of unmanned vending machine can reach this ampere of rank for unmanned vending machine not only can be used to ordinary occasion, still can be used to the place that has inflammable and explosive material such as filling station. Of course, the utility model provides a limit can circuit not only can be used to unmanned vending machine, can also be used to in other electrical apparatus that have explosion-proof requirement.

Example 2:

an energy limiting circuit is shown in fig. 2.

As shown in FIG. 2, the embodiment of the utility model provides a limit can circuit adopts two limits in FIG. 1 to establish ties after the circuit again for limit can circuit, strengthens limit can circuit's reliability, and this circuit is according to the design of ib explosion-proof requirement, through designing limit can circuit, satisfies explosion-proof requirement.

The present invention has been described in detail with reference to the accompanying drawings and embodiments, but those skilled in the art will understand that various specific parameters in the above embodiments can be changed without departing from the spirit of the present invention to form a plurality of specific embodiments, which are the common variation ranges of the present invention and will not be described in detail herein.

Claims

1. The energy limiting circuit comprises a voltage stabilizing circuit used for stabilizing input voltage, and is characterized by further comprising a signal amplifying circuit used for collecting and amplifying signals at the cathode output end of the energy limiting circuit, a signal comparing circuit used for comparing the signals amplified by the signal amplifying circuit, and a switch circuit used for controlling the on-off state of the input end of the energy limiting circuit according to feedback signals of the signal comparing circuit.

2. The energy limiting circuit of claim 1, wherein the voltage stabilizing circuit comprises a first diode D1 and a second diode D2 connected in parallel between the positive pole and the negative pole of the input end of the energy limiting circuit, and the first diode D1 and the second diode D2 are voltage stabilizing diodes.

3. The energy limiting circuit of claim 1, wherein the switching circuit comprises a MOS transistor Q1, a thyristor Q2, and a transistor Q3, wherein a source of the MOS transistor Q1 is connected to an anode of an input terminal of the energy limiting circuit, and a drain of the MOS transistor Q1 is connected to an anode of an output terminal of the energy limiting circuit; the control electrode of the controllable silicon Q2 is connected with the output end of the signal comparison circuit, the controllable silicon Q2 is electrically connected with the triode Q3 to control the on-off of the triode Q3, and the triode Q3 is electrically connected with the MOS tube Q1 to control the on-off of the MOS tube Q1.

4. The circuit of claim 1, wherein the signal comparison circuit comprises a first operational amplifier U1A, the first operational amplifier U1A receives the output signal of the signal amplification circuit for comparison and outputs a signal to control the switch circuit.

5. The energy limiting circuit of claim 1, wherein the signal amplifying circuit comprises a second operational amplifier U1B, the second operational amplifier U1B is configured to collect and amplify the signal at the negative terminal of the output terminal of the energy limiting circuit, and the second operational amplifier U1B transmits the amplified signal to the signal comparing circuit.

6. The energy limiting circuit of claim 1, wherein a third diode D3 is disposed between the switch circuit and the signal comparison circuit, and a cathode of the third diode D3 is connected to the switch circuit and an anode of the third diode D3578 is connected to the signal comparison circuit.

7. The energy limiting circuit of claim 1, wherein a fourth diode D4 is disposed between the signal comparison circuit and the signal amplification circuit, and a cathode of the fourth diode D4 is connected to the signal comparison circuit and an anode thereof is connected to the signal amplification circuit.