CN202257885U - Intelligent node of security system based on controller area network (CAN) bus - Google Patents

Abstract

The utility model provides an intelligent node of a security system based on a controller area network (CAN) bus, which comprises a monitoring alarm module, a signal acquisition processing module, a memory, an interface circuit and a selection module; wherein, the signal acquisition processing module is respectively connected with the monitoring alarm module, the memory and the interface circuit; the selection module is respectively connected with the monitoring alarm module and the signal acquisition processing module; the selection module is used for selecting the work type of the intelligent node; and consequently, the intelligent node monitors a scope of influence, can send an alarm signal as an alarm node, is flexible to use and meets the needs of different situations.

Description

Intelligent node based on CAN bus safety-protection system

Technical field

The utility model relates to a kind of intelligent node based on CAN bus safety-protection system, belongs to technical field of security and protection.

Background technology

Safety-protection system (SPS, security & protection system) is a purpose to safeguard social public security, is used for illegal invasion, and potential safety hazard etc. provide warning message.Existing safety-protection system mainly through in the protected location circumference (like enclosure wall) monitoring device (like infrared transceiver, vibration transducer, near the line of induction etc.) go up to be installed; Realize monitoring through monitoring device to its zone of action; When monitoring dangerous situation, report to the police through warning device.

Mostly existing safety-protection system is distributed control or the total line traffic control of RS485.Distributed control mode is as one to one or one-to-many, main control system directly or connects monitoring device indirectly through expansion module, aware switch amount signal is handled warning message in real time.This mode principle is simple, but construction wiring difficulty is big, expend many, follow-up maintenance upgrading difficulty.The RS485 bus mastering mode has solved the problems referred to above, but its total line use ratio is low, and data transmission rate is lower.

Propose on the same day the applicant in the patented claim of " based on the safety-protection system of CAN bus "; Wherein, intelligent node (comprising monitoring node and warning node) is used for its reach is carried out real-time monitoring, alarming, when dangerous situation occurring; In time and between the main control system communicate; Realization reports real-time and accurately that to alert therefore for safety-protection system, intelligent node is the key point that realizes its running.

The utility model content

The purpose of the utility model provides a kind of intelligent node based on CAN bus safety-protection system, and this intelligent node can carry out monitoring, alarming to its reach, uses flexibly, can satisfy the needs of safety-protection system.

The technical scheme that realizes the utility model is following:

A kind of intelligent node based on CAN bus safety-protection system comprises monitoring, alarming module, signal acquisition process module, storer, interface circuit and selects module; Wherein, the signal acquisition process module links to each other with monitoring, alarming module, storer and interface circuit respectively, selects module to advance to link to each other with monitoring, alarming module and signal acquisition process module respectively;

Select module to be used to select the job category of intelligent node;

When said intelligent node uses as monitoring node:

The monitoring, alarming module is used for its monitoring range is monitored; The signal acquisition process module is used for gathering in real time the signal that the monitoring, alarming module is monitored; And the signal of being gathered judged; When dangerous situation appears in judgement; Then utilize the physical address of this intelligent node of storing in the storer, generation comprises the alerting signal of this physical address and transfers out through interface circuit;

When said intelligent node uses as the warning node:

The signal acquisition process module receives the alerting signal of outside input through interface circuit; And the physical address on the said alerting signal judged; When address stored was identical in judging said physical address and storer, then signal acquisition process module activation monitoring, alarming module was sent alerting signal.

The said monitoring, alarming node of the utility model comprises active infra-red to love dart, temperature sensor, smoke transducer or its combination in any, further comprises sound and light alarm equipment simultaneously.

The said interface circuit of the utility model comprises the CTM8251 chip, and four electric capacity are respectively C1, C2, C3 and C4, and two resistance are respectively R1 and R2;

Wherein, the TXD pin of CTM8251 chip links to each other with the output terminal of intelligent node respectively with the RXD pin, and the VIN pin connects the 5V DC voltage, and further through C1 ground connection; The CANH pin connects the high level end of CAN bus, and further through capacitor C 2 ground connection; The CANL pin connects the low level end of CAN bus, and further through capacitor C 3 ground connection; Parallel resistance R1 between CANH pin and CANL pin; The CANG pin ground connection of CTM8251 chip, and further link to each other with the shielding end of CAN bus through R2, the while is shunt capacitance C4 at the two ends of R2.

Beneficial effect

The utility model is selected the function of intelligent node through selecting module, makes it can be used as monitoring node its reach is monitored, and can be used as the warning node again and sends alerting signal, uses the needs that can satisfy different situations flexibly.

Secondly; The utility model utilizes interface circuit to realize communicating by letter between intelligent node and the CAN bus; Wherein through parallel resistance R1 between the CANH of CTM8251 chip pin and CANL pin; When the signals transmission middle impedance is discontinuous, utilizes the shunting action of resistance to realize absorption, thereby improve serviceable life based on intelligent node in the safety-protection system of CAN bus to signal echo.

Once more, the utility model utilizes the energy absorption characteristics of R2 and the filtering characteristic of C4 through parallelly connected R2 and C4 between the shielding end of the CANG of CTM8251 chip pin and CAN bus, and radiation is little to external world to make the utility model interface circuit, and antijamming capability is strong.

Description of drawings

Fig. 1 is the structural representation of the utility model intelligent node.

Fig. 2 is the circuit diagram of interface circuit in the utility model intelligent node.

Embodiment

Further the utility model is elaborated below in conjunction with accompanying drawing

In Fig. 1, the utility model comprises monitoring, alarming module, signal acquisition process module, storer, interface circuit and selects module based on the intelligent node of CAN bus safety-protection system; Wherein, the signal acquisition process module links to each other with monitoring, alarming module, storer and interface circuit respectively, selects module to advance to link to each other with monitoring, alarming module and signal acquisition process module respectively.

Select module to be used to select the job category of intelligent node; For example when needs make intelligent node as its supervisory function bit of monitoring node performance; Select module to make the active infra-red that comprises on the monitoring, alarming node that love dart, temperature sensor, smoke transducer or its combination in any are worked, realize real-time monitoring situation in its reach.Select this moment module activation signal acquisition processing module to make it be in the state that signals collecting is judged; The signal acquisition process module is gathered the signal that the monitoring, alarming module is monitored in real time; And the signal of being gathered judged, when judgement dangerous situation occurs and swarms into police region if any the people; This moment, the signal acquisition process module was utilized the physical address of this intelligent node of storing in the storer, generated alerting signal and transferred out through interface circuit, so that the external control main frame receives signal and responds.

Select module to be used to select the job category of intelligent node; For example when making intelligent node do the time spent as its warning of warning node performance; The alerting signal of selecting module activation signal acquisition module interface circuit to transmit is judged; When the physical address of storing in the physical address on judging alerting signal and the storer was identical, then the signal acquisition module activation comprised that the monitoring, alarming module of audible-visual annunciator sends alerting signal, so that warn to the staff.

As shown in Figure 2, the utility model interface circuit comprises the CTM8251 chip, and four electric capacity are respectively C1, C2, C3 and C4, and two resistance are respectively R1 and R2; Wherein, C1, C2, C3 and C4 are the ceramic disc capacitor of 0.1uf, and the size of R1 is 120 Ω, and the size of R2 is 1M Ω.

When intelligent node during to CAN bus transfer signal, then the TXD pin of CTM8251 chip and the current potential on the RXD pin change, and the signal of required transmission CANH pin and the CANL pin through the CTM8251 chip is transferred to the CAN bus; Because the signals transmission middle impedance is discontinuous, the potentiometer R1 that is parallel between CANH pin and the CANL pin is used to adsorb echo reflection.The R2 that is parallel to simultaneously between the shielding end of CANG pin and CAN bus can further absorb backward energy, and C4 can play filter action to the signal that is transmitted simultaneously.

When CAN bus during to the intelligent node transmission signals, in this interface circuit the effect of resistance and electric capacity same as described above, therefore do not do further tired stating.

Though described the embodiment of the utility model in conjunction with accompanying drawing; But technician for the present technique field; Under the prerequisite that does not break away from the utility model, can also do some distortion, replacement and improvement, these also are regarded as belonging to the protection domain of the utility model.

Claims (3)

1. the intelligent node based on CAN bus safety-protection system is characterized in that, comprises monitoring, alarming module, signal acquisition process module, storer, interface circuit and selects module; Wherein, the signal acquisition process module links to each other with monitoring, alarming module, storer and interface circuit respectively, selects module to advance to link to each other with monitoring, alarming module and signal acquisition process module respectively;

Select module to be used to select the job category of intelligent node;

When said intelligent node uses as monitoring node:

The monitoring, alarming module is used for its monitoring range is monitored; The signal acquisition process module is used for gathering in real time the signal that the monitoring, alarming module is monitored; And the signal of being gathered judged; When dangerous situation appears in judgement; Then utilize the physical address of this intelligent node of storing in the storer, generation comprises the alerting signal of this physical address and transfers out through interface circuit;

When said intelligent node uses as the warning node:

The signal acquisition process module receives the alerting signal of outside input through interface circuit; And the physical address on the said alerting signal judged; When address stored was identical in judging said physical address and storer, then signal acquisition process module activation monitoring, alarming module was sent alerting signal.

2. intelligent node according to claim 1 is characterized in that, said monitoring alarm node comprises active infra-red to love dart, temperature sensor, smoke transducer or its combination in any, further comprises sound and light alarm equipment simultaneously.

3. intelligent node according to claim 1 is characterized in that said interface circuit comprises the CTM8251 chip, and four electric capacity are respectively C1, C2, C3 and C4, and two resistance are respectively R1 and R2;

Wherein, the TXD pin of CTM8251 chip links to each other with the output terminal of intelligent node respectively with the RXD pin, and the VIN pin connects the 5V DC voltage, and further through C1 ground connection; The CANH pin connects the high level end of CAN bus, and further through capacitor C 2 ground connection; The CANL pin connects the low level end of CAN bus, and further through capacitor C 3 ground connection; Parallel resistance R1 between CANH pin and CANL pin; The CANG pin ground connection of CTM8251 chip, and further link to each other with the shielding end of CAN bus through R2, the while is shunt capacitance C4 at the two ends of R2.

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