CN2158096Y - Chopper - Google Patents

Abstract

The utility model relates to a chopper. The utility model is mainly composed of a direct current power supply, a speed regulation and stabilization circuit, a chopping disk, a photoelectric isolation switch, a shaping circuit, a frequency display system, and an amplifier. The integral type chopper is assembled by the collection of all the components, overcoming the defects of an existing chopper, wherein, the defects of the existing chopper refer to that the existing chopper is divided into two bodies, and digital frequency is not displayed.

Description

The utility model belongs to light energy modulation instruments.

The existing light cutter is mainly composed of a power supply, a transformer, a frequency modulation and frequency display electronic system, a motor and a cutting disk. Said motor is generally a stepping motor or a DC tachomotor unit. In terms of the overall structure, in order to be commensurate with photoelectric receivers, amplifiers and other electronic instruments, a small volume is generally pursued. Therefore, the existing light chopper generally separates the power supply and the electronic system from other parts to form a two-body separated structure. There is also a power supply and a transformer made into one, and the rest of the parts are made into one. The former is smaller in size, while the latter is larger in size and looks more comfortable. However, all two-body split light choppers are inconvenient to use. In addition, none of the existing light choppers has a digital frequency meter for real-time monitoring of the frequency, but only a dial indicating the light cutting frequency as an indication when adjusting the frequency. If you want to know whether the cut-off frequency is accurate and stable during work, you must additionally connect a digital frequency meter for real-time monitoring.

In order to overcome the above-mentioned shortcomings, the utility model improves the existing light cutter, and designs an integral light cutter with a small volume and a digital frequency display system to display the light cutting frequency in real time.

The technical solution of the utility model is to use the armature current sampling method with a simple structure to adjust and control the motor speed, which simplifies the control circuit and can use an ordinary DC motor, thereby greatly reducing the volume. In addition, a very small and highly integrated digital frequency display circuit is used and the display screen is placed on the panel of the light cutter to display the light cutting frequency in real time.

The specific structure of the utility model is illustrated below in conjunction with the accompanying drawings. The utility model is mainly composed of a DC power supply 1, a speed regulating and stabilizing circuit 2, a cutting disc 3, a photoelectric isolating switch 4, a shaping circuit 5, a frequency display circuit 6 and an amplifier 7 . Insert the power plug into the 220-volt mains socket, after the DC power becomes DC, the motor in the speed-regulating and stabilizing circuit drives the cutting disk 3 with many holes or gaps on the edge to rotate at the required speed At this time, the incident light beam of the cutting disc is cut into intermittent light beams, and the speed of the motor is set by the speed regulating potentiometer W of the speed regulating and stabilizing circuit according to the required light cutting frequency. When the cutting disk 3 rotates, the photoelectric isolating switch placed on its periphery also outputs a synchronous electrical signal with the same frequency as the light cutting frequency, which is divided into two channels after being shaped by the shaping circuit, one of which is sent to the frequency display system to adjust the light cutting frequency displayed in real time. The frequency display system is composed of second pulse generation and reset circuit, 7217 general calculator chip and liquid crystal display. The other way is sent to the amplifier 7 to amplify and output a frequency signal to the socket 8 of the signal output line in Fig. 3 .

The above-mentioned speed regulating and stabilizing circuit is shown in Figure 2, which is mainly composed of speed regulating potentiometer W, comparator I, ordinary DC motor M, amplifiers II, III and resistor R. Suppose the resistance of the motor armature is R _a , the armature current is ia , the potential constant of the electric potential is K _e , the angular velocity of the motor is ω, the amplification factor of the amplifier II is K, the _output voltage of the comparator is V, and the output voltage of the amplifier III is The output voltage is V _g , then:

V = (R _a + R _s ) i _a + K _e ω

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\mathrm{<span\; class="notranslate">\; V</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; K</span>}\frac{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="R\; f\; R"\; filenames="932047394\_DRIMG1.png,932047394\_DRIMG2.png"\; state="\{\{state\}\}">R</figure-callout></span><figure-callout\; id="2"\; label="R\; f\; R"\; filenames="932047394\_DRIMG1.png,932047394\_DRIMG2.png"\; state="\{\{state\}\}">\; </figure-callout>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}{{}_{}}\mathrm{<span\; class="notranslate">\; vs.</span>}$

When satisfying the conditions R ₁ =R ₂ , R _a =(K+1)R _s and K<0,

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}\mathrm{<span\; class="notranslate">\; \&alpha;ipa</span>}$

Therefore, the output voltage V _g of the amplifier III is proportional to the rotational speed ω of the motor and is applied to the negative input of the comparator I, whose positive input is connected to the reference level V _i , which is adjusted by the Speed potentiometer W setting. The output of the comparator controls the voltage at both ends of the motor M. When the speed of the motor becomes smaller, V _g drops, which increases the voltage V output by the comparator, so the motor is accelerated. When the motor speed increases, V _g rises, making the output voltage V of the comparator drop, so the motor is decelerated. The terminal voltage of the motor is stable only when V _g is close to the reference level V _i . When the speed of the motor needs to be changed, the required motor speed can be obtained only by adjusting the reference level V _i . This method of adjusting and controlling the motor speed is the armature current sampling method.

Fig. 3 is the outline structure of the present utility model, and the meaning represented by the numeral wherein is identical with Fig. 1.

The utility model has the advantage that all the parts are assembled into one body, and there is a digital frequency display system, which can display the cut-off frequency in real time, so that the cut-off frequency and its stability can be known at any time, thus overcoming the separation of existing cut-off devices Into two bodies and no digital frequency display disadvantages.

Claims (2)

1, a kind of chopper, mainly by direct supply [1], governing speed and steady speed controlled circuit [2], cut CD [3], photoelectric switch [4], shaping circuit [5], frequency display system [6] and amplifier [7] and formed, it is characterized in that the circuit that governing speed and steady speed controlled circuit is made up of speed-regulating potentiometer [W], comparer [I], common DC motor [M], amplifier [II, III] and resistance R.

2,, it is characterized in that the frequency display system is by pulse per second (PPS) generation and reset circuit, the numerical frequency display system that 7217 universal counter chips and LCD are formed according to the described chopper of claim 1.

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