A bus safety window opening alarm

Abstract

The utility model discloses a bus safety window opening alarm, including main control circuit, detection module, alarm module and power module, and main control circuit adopts special alarm chip ATW51H. Detection module is connected through JP1, JP2 interface, and is connected in parallel 16V / 0.1muF filter capacitor C2 to filter out the spurious echo, the drive circuit of alarm module is two stage series connection structure, is composed of triode Q3, triode Q2 and transformer T1, can enhance the driving capacity and protect the element, and power module contains triode Q1, switch S1 and LED pilot lamp D1, realizes the power supply management and control and state indication. Special alarm chip pin connection is reasonable, and the stability is promoted with the cooperation of auxiliary resistance. The alarm aims at improving the accuracy of safety window opening state detection, driving reliability and operating stability, realizes real -time monitoring and reliable alarm.

Description

Technical Field

[0001] This utility model relates to the field of safety monitoring, and in particular to a bus safety window opening alarm. Background Technology

[0002] As a crucial facility for ensuring passenger escape in emergencies, the real-time and accurate monitoring and timely alarm of the opening status of bus safety windows are of great significance for improving the safety of bus operations. However, existing alarm devices for bus safety windows have many shortcomings: the detection module lacks effective filtering, making it susceptible to interference from high-frequency noise, leading to false alarms or missed alarms in determining the opening status of the safety window; the alarm drive circuit is mostly single-stage drive with limited signal amplification capability, making it difficult to stably drive the horn to sound, and it lacks an effective freewheeling protection mechanism, making it easy for the induced electromotive force generated by sudden changes in transformer coil current to damage circuit components; the power supply module's power supply control is not precise enough, lacking intuitive operating status indicators, and components such as transistors in the circuit are prone to affecting overall operational stability due to overcurrent or potential instability. These problems all make it difficult for existing alarm devices to meet the monitoring requirements of bus safety windows in terms of reliability, accuracy, and safety. Utility Model Content

[0003] The purpose of this invention is to provide a bus safety window opening alarm, which solves the above-mentioned problems.

[0004] This utility model is achieved through the following technical solution:

[0005] A bus safety window opening alarm includes a main control circuit, a detection module, an alarm module and a power supply module. The main control circuit uses a dedicated alarm chip ATW51H. Its pins B3, B4 and B5 are connected to the interfaces JP1 and JP2 of the detection module, respectively. The pin VSS is grounded and the pin VC filter capacitor C2 is connected to the VCC output of the power supply module.

[0006] The alarm module includes a first-stage drive circuit, a second-stage drive circuit, and a speaker LS1 connected in series.

[0007] The first-stage driving circuit is composed of transistor Q3: the output terminal OUT of the ATW51H chip is connected to the base of transistor Q3 through the current-limiting resistor R10, and the emitter of transistor Q3 is grounded.

[0008] The second-stage drive circuit consists of transistor Q2: the collector of transistor Q3 is connected to the base of transistor Q2 through resistor R5, and the emitter of transistor Q2 is grounded.

[0009] The collector of transistor Q2 is connected to one end of the primary coil of transformer T1, and the other end of the primary coil of transformer T1 is connected to VCC output by the power module.

[0010] The secondary coil of transformer T1 is connected to speaker LS1.

[0011] Furthermore,

[0012] The power module includes a transistor Q1, a switch S1, and an LED indicator D1. The emitter of transistor Q1 is connected to the input power supply BAT. The base of transistor Q1 is connected to the output terminal of switch S1 through resistor R2 and grounded through resistor R1. The collector of transistor Q1 outputs VCC power. The positive terminal of LED indicator D1 is connected to the collector of transistor Q1 through current-limiting resistor R12, and the negative terminal is grounded.

[0013] Furthermore,

[0014] The detection module includes a filter capacitor C2 connected in parallel between the detection circuits JP1 and JP2 and ground. The filter capacitor C2 is a 16V / 0.1μF capacitor.

[0015] Furthermore,

[0016] A freewheeling diode D2 is connected in parallel across the primary coil of the transformer T1. The anode of D2 is connected to the collector of transistor Q2, and the cathode is connected to VCC.

[0017] Furthermore,

[0018] A pull-down resistor R13 is connected in parallel between the base of the transistor Q3 and ground.

[0019] Furthermore,

[0020] A voltage divider resistor R3 is connected in series between the base of the transistor Q2 and ground.

[0021] The beneficial effects of this utility model are:

[0022] 1. The 16V / 0.1μF filter capacitor C2 connected in parallel in the detection module can effectively filter out high-frequency noise and interference signals in the JP1 and JP2 detection circuits. The 16V withstand voltage is adapted to the normal operating voltage of the circuit, and the 0.1μF capacitance matches the frequency characteristics of the detection signal, thereby reducing false judgments caused by signal fluctuations. This allows the dedicated alarm chip ATW51H to receive and judge the opening status of the safety window more accurately, providing a reliable input basis for subsequent alarm actions.

[0023] 2. The two-stage series drive circuit composed of transistors Q3 and Q2 can amplify the weak signal output by the chip step by step, improving the driving capability of the speaker; transformer T1 achieves voltage matching to ensure that the speaker obtains a suitable operating voltage; freewheeling diode D2 can discharge the induced electromotive force when the transformer coil current changes suddenly, avoiding high voltage damage to components. The three work together to allow the speaker to emit an alarm sound stably, while protecting the circuit components and improving the overall reliability of the alarm system.

[0024] 3. The power module achieves effective power supply control and status visualization. Transistor Q1 controls its base potential through switch S1, thereby controlling the VCC power output and achieving precise control over the power supply to the alarm. LED indicator D1 is connected to the power output terminal through current-limiting resistor R12, which can intuitively display whether the power supply is normal, allowing users to quickly judge the power supply status. Resistors R1, R2, and current-limiting resistor R12 play a role in voltage division and current limiting, preventing overcurrent damage to components and ensuring the long-term stable operation of the power module, providing continuous and reliable power support for the entire alarm.

[0025] 4. Pins B3, B4, and B5 of the dedicated alarm chip ATW51H are connected to the JP1 and JP2 detection circuits to ensure real-time reception of the safety window status signal; the VC filter capacitor C2 is connected to the VCC of the power module to obtain a stable power supply, and the VSS pin is grounded to provide a reference potential. This pin connection method allows the chip to receive signals stably and operate normally, providing core protection for the judgment of the safety window opening status and the output of alarm commands.

[0026] 5. The pull-down resistor R13 at the base of transistor Q3 pulls the base potential to ground when the OUT terminal of the alarm chip is low, ensuring reliable cutoff of transistor Q3 and preventing false turn-on. The voltage divider resistor R3 at the base of transistor Q2 stabilizes the base voltage of transistor Q2 when transistor Q3 is on, ensuring it operates in a suitable state. Together, they reduce the possibility of circuit malfunction and improve the working stability and anti-interference capability of the alarm drive circuit. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0030] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inner", "outer", "front", "rear", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0031] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "have," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] See the example. Figure 1 :

[0033] A bus safety window opening alarm includes a main control circuit, a detection module, an alarm module and a power supply module. The main control circuit uses a dedicated alarm chip ATW51H. Its pins B3, B4 and B5 are connected to the interfaces JP1 and JP2 of the detection module, respectively. The pin VSS is grounded and the pin VC filter capacitor C2 is connected to the VCC output of the power supply module.

[0034] The alarm module includes a first-stage drive circuit, a second-stage drive circuit, and a speaker LS1 connected in series.

[0035] The first-stage driving circuit is composed of transistor Q3: the output terminal OUT of the ATW51H chip is connected to the base of transistor Q3 through the current-limiting resistor R10, and the emitter of transistor Q3 is grounded.

[0036] The second-stage drive circuit consists of transistor Q2: the collector of transistor Q3 is connected to the base of transistor Q2 through resistor R5, and the emitter of transistor Q2 is grounded.

[0037] The collector of transistor Q2 is connected to one end of the primary coil of transformer T1, and the other end of the primary coil of transformer T1 is connected to VCC output by the power module.

[0038] The secondary coil of transformer T1 is connected to speaker LS1.

[0039] The detection module (JP1 / JP2) acquires the safety window status signal in real time and inputs it to the B3 / B4 / B5 pins of the dedicated chip ATW51H. After analyzing the signal, the chip outputs a control command from the OUT terminal. The weak current signal is amplified step by step through a two-stage series transistor drive circuit (transistor Q3 → transistor Q2) and finally drives the transformer T1 to boost the voltage to meet the working requirements of the speaker LS1. At the same time, the system achieves energy coordination through a unified power supply node VCC. VCC supplies power to the VC filter capacitor C2 pin of the chip and provides the working voltage for the primary coil of the transformer T1, forming a closed-loop control link.

[0040] Furthermore,

[0041] The power module includes a transistor Q1, a switch S1, and an LED indicator D1. The base of the transistor Q1 is connected to the output terminal of S1 through a resistor R2 and grounded through a resistor R1. The collector outputs VCC power. The positive terminal of D1 is connected to the collector of the transistor Q1 through a current-limiting resistor R12, and the negative terminal is grounded.

[0042] Transistor Q1 acts as a switch here, controlling the base potential by switching switch S1 on and off, which in turn controls the output of the collector VCC power supply, thus achieving effective control over the power supply of the entire alarm. LED indicator D1 is connected to the power output terminal through current-limiting resistor R12, which can intuitively show whether the power supply is working properly, allowing users to quickly judge the power supply status. Resistors R1, R2 and current-limiting resistor R12 respectively play the roles of voltage division and current limiting, preventing components from being damaged by overcurrent and ensuring the long-term stable operation of the power module.

[0043] Furthermore,

[0044] The detection module includes a filter capacitor C2 connected in parallel between the detection circuits JP1 and JP2 and ground. The filter capacitor C2 is a 16V / 0.1μF capacitor.

[0045] The detection module connects a filter capacitor C2 in parallel between the JP1 and JP2 detection circuits and ground. The parameters of the filter capacitor C2 are 16V / 0.1μF. The capacitor is used to achieve the filtering connection between the circuit and ground.

[0046] The 16V / 0.1μF filter capacitor C2 effectively filters out high-frequency noise and interference signals in the JP1 and JP2 detection circuits, avoiding false detections caused by signal fluctuations. The 16V withstand voltage ensures stable operation of the capacitor under the normal operating voltage of the circuit, while the 0.1μF capacitance is adapted to the signal frequency characteristics of the detection circuit, thereby improving the accuracy and stability of the detection module in judging the opening status of the safety window.

[0047] Furthermore,

[0048] A freewheeling diode D2 is connected in parallel across the primary coil of the transformer T1. The anode of D2 is connected to the collector of transistor Q2, and the cathode is connected to VCC.

[0049] Furthermore,

[0050] The power module includes a transistor Q1, a switch S1, and an LED indicator D1. The base of the transistor Q1 is connected to the output terminal of S1 through a resistor R2 and grounded through a resistor R1. The collector outputs VCC power. The positive terminal of D1 is connected to the collector of the transistor Q1 through a current-limiting resistor R12, and the negative terminal is grounded.

[0051] Transistor Q1 acts as a switch here, controlling the base potential by switching switch S1 on and off, which in turn controls the output of the collector VCC power supply, thus achieving effective control over the power supply of the entire alarm. LED indicator D1 is connected to the power output terminal through current-limiting resistor R12, which can intuitively show whether the power supply is working properly, allowing users to quickly judge the power supply status. Resistors R1, R2 and current-limiting resistor R12 respectively play the roles of voltage division and current limiting, preventing components from being damaged by overcurrent and ensuring the long-term stable operation of the power module.

[0052] Furthermore,

[0053] A pull-down resistor R13 is connected in parallel between the base of the transistor Q3 and ground.

[0054] When the OUT terminal of the alarm chip is at a low level, the pull-down resistor R13 can pull the base potential of transistor Q3 to near ground potential, ensuring that transistor Q3 is reliably cut off and avoiding false turn-on caused by residual base voltage;

[0055] Furthermore,

[0056] A voltage divider resistor R3 is connected in series between the base of the transistor Q2 and ground.

[0057] The voltage divider resistor R3, together with resistor R5, can stabilize the base voltage of transistor Q2 when transistor Q3 is turned on, so that transistor Q2 works in a suitable conduction state and avoids abnormal driving caused by excessively high or low base voltage.

[0058] The method of using this utility model is as follows:

[0059] During use, the power module is started by controlling switch S1. At this time, transistor Q1 conducts due to the change in base potential, and the collector outputs VCC power to power the entire device. LED indicator D1 lights up to indicate that the power supply is normal. The detection module monitors the safety window status in real time through the JP1 and JP2 interfaces. The parallel 16V / 0.1μF filter capacitor C2 filters out high-frequency noise to ensure the stability of the detection signal. The dedicated alarm chip ATW51H receives the detection signal through pins B3, B4, and B5 (the chip is powered by the VC filter capacitor C2 pin, and the VSS pin is grounded to provide a reference potential).

[0060] When the safety window is opened, causing an abnormal detection signal, the ATW51H chip judges the situation and outputs an abnormal level from the OUT terminal. This level is then sent to the base of transistor Q3 via the current-limiting resistor R10. After transistor Q3 is turned on, the signal is transmitted to the base of transistor Q2 through resistor R5 (the pull-down resistor R13 of transistor Q3 ensures reliable cutoff when the level is low, and the voltage divider resistor R3 of transistor Q2 stabilizes its operating state). The two series-connected transistors amplify the weak signal and drive transformer T1. Transformer T1 adapts the voltage of speaker LS1 through voltage conversion, causing it to emit an alarm sound. At the same time, the freewheeling diode D2 at both ends of the transformer provides a discharge circuit for the induced electromotive force when the coil current changes abruptly, preventing component damage. This achieves real-time monitoring and reliable alarm of the safety window's open status.

[0061] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A bus safety window opening alarm, comprising a main control circuit, a detection module, an alarm module, and a power supply module, characterized in that: The main control circuit uses a dedicated alarm chip ATW51H. Its pins B3, B4, and B5 are connected to the interfaces JP1 and JP2 of the detection module, respectively. Pin VSS is grounded, and pin VC filter capacitor C2 is connected to the VCC output of the power module. The alarm module includes a first-stage drive circuit, a second-stage drive circuit, and a speaker LS1 connected in series. The first-stage driving circuit is composed of transistor Q3: the output terminal OUT of the ATW51H chip is connected to the base of transistor Q3 through the current-limiting resistor R10, and the emitter of transistor Q3 is grounded. The second-stage drive circuit consists of transistor Q2: the collector of transistor Q3 is connected to the base of transistor Q2 through resistor R5, and the emitter of transistor Q2 is grounded. The collector of transistor Q2 is connected to one end of the primary coil of transformer T1, and the other end of the primary coil of transformer T1 is connected to VCC output by the power module. The secondary coil of transformer T1 is connected to speaker LS1.

2. The bus safety window opening alarm according to claim 1, characterized in that, The power module includes a transistor Q1, a switch S1, and an LED indicator D1. The emitter of transistor Q1 is connected to the input power supply BAT. The base of transistor Q1 is connected to the output terminal of switch S1 through resistor R2 and grounded through resistor R1. The collector of transistor Q1 outputs VCC power. The positive terminal of LED indicator D1 is connected to the collector of transistor Q1 through current-limiting resistor R12, and the negative terminal is grounded.

3. The bus safety window opening alarm according to claim 1, characterized in that, The detection module includes a filter capacitor C2 connected in parallel between the detection circuits JP1 and JP2 and ground. The filter capacitor C2 is a 16V / 0.1μF capacitor.

4. A bus safety window opening alarm as described in claim 1, characterized in that, A freewheeling diode D2 is connected in parallel across the primary coil of the transformer T1. The anode of D2 is connected to the collector of transistor Q2, and the cathode is connected to VCC.

5. A bus safety window opening alarm as described in claim 1, characterized in that, A pull-down resistor R13 is connected in parallel between the base of the transistor Q3 and ground.

6. A bus safety window opening alarm as described in claim 1, characterized in that, A voltage divider resistor R3 is connected in series between the base of the transistor Q2 and ground.

Images