CN2197264Y - Thief alarm for truck - Google Patents

Abstract

The utility model discloses a load-weight anti-theft alarm for automobiles, composed of a sensor, an oscillator, a computer, and a control circuit. The utility model uses a displacement sensor to measure the deformation quantity generated by the load-weight spring of the automobile when the load is changed, and the computer carries out data processing. When the automobile or the goods loaded are stolen, the alarm can send various audible and visual alarming signals, the circuit is cut, the automobile can not be moved, and the stealing is prevented.

Description

Thief alarm for truck

The utility model relates to a kind of automobile burglar technology defense device, belongs to car electrics.

At present, car alarm no matter be infrared type or induction type, be and prevent that the burglar from opening car door, in case car door is opened, promptly loses protective action and all can not prevent losing of vehicle-mounted cargo simultaneously.Do not see antitheft protective device and the report that utilizes the automobile loading to change to report to the police or control arranged.

The utility model is simple, cheap being installed on the various automobiles of a kind of manufacturing that provides for the defective that overcomes present commercially available various car alarms, both can prevent that automobile from losing, and can prevent the burglar alarm of loss of goods again.

Principle of work of the present utility model is the deformation that utilizes the automobile weighted spring must produce when the loading amount changes, and measures this deformation quantity, is converted into electric signal, and gives little process computer and carry out data handing, reaches the purpose of reporting to the police and controlling.Any automobile and institute's cargo stolen all needs the people into the car or lie prone and go up the compartment and could take place, and this with regard to the loading that makes automobile variation has taken place, and just deformation will take place the weighted spring of automobile.Therefore, lock car door even the personnel that sail of department forget from car the time, or forget and take off the ignition trigger key,, just can in time report to the police and the point of cutoff ignition circuit as long as there is the people into the car.This loading formula car alarm is characterised in that: a displacement pickup is installed between automotive frame and weighted spring, and displacement pickup and an oscillator are fitted together.When spring produced deformation, sensor was delivered to the computer controlled capsule that is installed in the operator's compartment with deformation quantity by the electric signal that oscillator is converted into a frequency change.Because sensor and oscillator are contained in the same shielding capsule, therefore can not be subjected to extraneous electromagnetic interference.Because transferring to the electric signal of computing machine is frequency signal, in the transmission course, can not produce frequency-distortion, guaranteed the reliable and stable of work.Simultaneous computer can directly count frequency values and need not to carry out analogue to digital conversion, thereby has simplified equipment, has reduced cost.

Accompanying drawing 1 is a functional-block diagram of the present utility model.(1) is displacement pickup among the figure, is installed between automotive frame and the weighted spring.It can be the power transformation capacity sensor, also can be variable inductance formula sensor, and general minibus is installed near the front-wheel of chaufeur one side, and cargo truck can be contained between hind axle and the crossbeam, also can respectively adorn one in front and back.(2) are oscillators among the figure, and the sensor that is made of electric capacity or inductance is its oscillation circuit.When capacitance or inductance value change, oscillation frequency also changes thereupon.Oscillator and sensor are contained in the same shielding capsule.(3) are computing machines among the figure, it to oscillator output displacement--frequency signal is counted, and, export multiple signal and give control circuit according to the frequency change difference of setting.(4) are control circuits among the figure.It is made up of amplifying circuit and relay, and according to the signal that computing machine provides, Control of Automobile loudspeaker and light send multiple sound and light alarm signal, and according to the time cut-out automotive ignition power supply of setting.(5) are electric power loops among the figure, because automobile power source is 12V.DC, it is 5V.DC that computing machine needs with power supply, and step-down and pressure stabilization function are played in this loop.

This annunciator can't destroy outside car, and when power supply that cuts off the sensing capsule and signal wire (SW), vibration stops, and has also promptly produced frequency change, reports to the police immediately.

Description of drawings: Fig. 1 is the functional-block diagram of loading formula car alarm

Fig. 2 is capacitive sensor structure figure

Fig. 3 is schematic circuit diagram

Embodiment of the present utility model:

Displacement pickup (1) adopts capacitance-type sensor, and its structure is an accompanying drawing 2, among the figure

Be respectively two garden tubular pole plates, wherein internal polar plates of cond With the displacement conductive bar

Link to each other,

6. being respectively the positioning seat of external electrode, 7. is interior electrode location copper pipe, 8. is that interior electrode copper is formulated the termination, position, 9. is retracing spring, interior electrode

By 7. 8. 9. being connected to become the ground terminal of electrode with shell.10. be the metal mask shell, (11) are big sensor adapter plate, and (12) are the oscillator printed board.When the conductive bar that withstands on the automobile weighted spring

When producing displacement with spring, interior electrode Change thereupon, capacitance is changed.

Present embodiment adopts integrated package NE555 to form RC astable oscillator (2) by standard circuit. see accompanying drawing 3.When R1.R2. is respectively 30K Ω. during with 100K Ω, the aforesaid displacement pickup of adapted, displacement are 0.5 millimeter, changeable frequency 1.5KC.Oscillator and sensor are contained in the same capsule, and this sensor oscillation capsule always has three external lines, that is: power supply ten, power supply one and output line.

Computing machine in the present embodiment (3) adopts 8031 chip microprocessors (CPU), and 2716 is memory under program (EPROM), and the T1 mouth input frequency signal by 8031 carries out timer counter, 8031 P10, P11 carry out bit control signal.

Control circuit in the present embodiment (4) is by NPN aerotron Q1.Q2 and relay J 1, J2 forms, Q1, Q2 receives by computing machine 8031P10, and the signal that the P11 mouth is sent here carries out direct current and amplifies, control J1, the adhesive of J2, release, the contact of J1, Control of Automobile loudspeaker, car light send different length sound and light alarm signal at interval, and the automotive ignition power supply is cut off in J2 control.

Power supply in the present embodiment adopts 7805 integrated packages, with automobile power source 12V, is reduced to 5V.

The utility model has the advantages that: handling ease, with low cost, easy for installation, can be installed in passenger vehicle, on the automobile of the various vehicles such as lorry, can carry out anti-thefting monitoring to car body and institute's cargo simultaneously, not to be afraid of outside car and to destroy, sensitivity is 20kg.

Claims (1)

1, a kind of loading formula car alarm is made up of sensor, oscillator, little process computer and control circuit, it is characterized in that:

1.. condenser or inductive displacement transducer (1) are installed between automotive frame and the automobile weighted spring, the deformation of weighted spring is become the variation of electric capacity or inductance value, the loop element that serves as oscillator (2), and be contained in the same shielding capsule with oscillator;

2.. form chromacoder by oscillator (2) and computing machine (3), what oscillator (2) flowed to computing machine (3) is frequency signal, carries out data handing by computing machine (3).

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