SU1458227A1 - Arrangement for regulating feed speed in saw frames - Google Patents

Abstract

The invention relates to woodworking. The purpose of the invention is to improve the quality of lumber. The device contains a feed drive type 1 generator-motor, a photo sensor 4 mounted on support 5 of the front upper roller 6, voltage source Up connected to it by outputs 9 and 10 potentiometer RI, engine 11 which is connected to the winding of the exciter generator 2 through rheostat R2. Parallel to rectifier R2, a composite transistor yiV2 is connected, the control circuit of which contains capacitor C1, voltage divider, Zener diode V4 and output relay K1 of photosensor 4. In the absence of a log in the rollers, the VIV2 transistor is closed, the feed rate is minimal. When the beam ends 7 of the photosensor 4 are switched by the front end, the transistor VIV2 opens smoothly, which leads to a smooth penetration of the feed rate. After exiting the front-ass rollers; But the feed rate is gradually reduced to the minimum. 3 il. i cl c 4 SP 00 tc y

Description

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The invention relates to woodworking and can be used in sawmill equipment.

The purpose of the invention is the capillary behavior.

FIG. 1 shows a diagram of the proposed device; in fig. 2 - the moment of entry of the top of the log into the front, feed rollers and block the photosensor beam with them; in fig. 3 - the moment of opening the photosensor beam when the room leaves the front feed rollers and enters the top of the next log,

FIG. 1, using Up and Ш, denotes the voltages going to potentiometer R1, by means of which

and rheostat R2. The resistance R6 is connected between the collector and the base of the composite transistor VIV2. Between the base and the emitter of the composite transistor V1V2 are connected (through the resistance R5) Zener diode V4 and diode V5 interconnected. It protects the composite transistor VIV2 from overloads and helps to comply with the required mode of its operation. In parallel to the composite transistor V1V2 and in its collector circuit, diodes V6 and V7j protecting this transistor against reverse voltage are connected when switching power and reversing the supply drive Resistors R3, R4, R5 and R6 form a voltage divider. The device is configured as follows

the nominal feed rate is given, and to the motor field at -20.

water supply, and after 11 - for example, at the extreme left position, the field supply field of the generator excitation winding determines the nominal feed rate.

The plug 11 of the potentiometer RI, which corresponds to the maximum transfer speed, opens the contact K1 and selects the resistance value R6 at which the composite transistor VIV opens fully and shorts the residual R2. Then, the slider 11 is set to the position corresponding to the Average value, which is usually applied to the nominal feed rates, and the contact K1 is released. In this case, capacitor C1 is charged through the resistance R3 with a negative voltage. The voltage squeezed from the R5 and R6 splitter tap and limited by the zener diode V4 is applied to the base of the V1V2 composite transistor, causing it to smoothly close. Thereby, rheostat R2 is smoothly introduced into operation, the voltage across the excitation winding of generator 2 also decreases smoothly, and the feed rate decreases accordingly. Duration close sos

A device for controlling the feed rate in the timber frames comprises a feed drive consisting of an AC motor 1, a generator 2 and a DC motor 3, potentiometer R1., A rheostat R2,

Photo sensor 4 and output relay with (open) contact K1, Prrchem photo sensor 4 is mounted on supports 5 of the front upper feed roller 6 so that axis 7 of the phototour (beam) passes below the lower generator of this roller and therefore overlaps when the log 8 is in the front feed rollers. The output of the photo sensor 4 is connected to the winding of the relay K. The device also has a composite transistor V1V2 and a capacitor C1. This transistor is connected by a paramotor

The plug 11 of the potentiometer RI, which corresponds to the maximum feed rate, opens the contact K1 and picks up such a resistance value R6 at which the composite transistor VIV2 opens fully and shuns the resistor R2. Then, the slider 11 is set to the position corresponding to the Average value of the normally used nominal feed rates, and the contact K1 is released. In this case, the capacitor C1 is charged through the resistance R3 with a negative voltage. The voltage squeezed from the R5 and R6 splitter tap and limited by the zener diode V4 is applied to the base of the V1V2 composite transistor, causing it to smoothly close. Thereby, rheostat R2 is smoothly introduced into operation, the voltage across the excitation winding of generator 2 also gradually decreases, and the feed rate decreases accordingly. The duration of the closure of R2, included in the power supply circuit of the excitation winding of the generator 2. One VJV2 transformer equal to the required capacitor C 1 is connected, but the duration of the speed reduction through the resistance R4 and R5 with the supply base before the output of the components of the composite transistor Viv2. Through from the front feed rollers, the us-resistance of the R3 diode V3, which prevents the flow of the positive voltage into the circuit, and the contact K1. This plate is connected with an extreme degree by selecting the resistance value R3. After that contact K1. open and capacitor C is discharged until the voltage drops directly at the base-emitter 1V2 junction. During the initial discharge of the capacitor C1, the composite transistor VIV2 is closed and the feed rate is reduced by the amount determined by the rheostat R2. During the subsequent discharge of the capacitor GI, the composite transistor

House 9 of potentiometer R1, from the other extreme terminal 10 and the slider of which is removed the direction of U, supplying the excitation winding of generator 2. The second plate of capacitor C1 is connected to the slider 11 of potentiometer R1 ..

and rheostat R2. Between the collector and the base of the composite transistor VIV2 is included the resistance R6. Between the base and the emitter of the composite transistor V1V2 are connected (through the resistance R5) the zener diode V4 and the diode V5 interconnected. They protect the composite transistor VIV2 from overloads and help to comply with the required mode of its operation. In parallel, the composite transistor V1V2 and its collector circuit include diodes V6 and V7j protecting this transistor against reverse voltage when switching power and reversing the supply drive Resistors R3, R4, R5 and R6 form a voltage divider. The device is configured as follows.

in a way.

In the extreme left position,

The pin 11 of the potentiometer RI, which corresponds to the maximum feed rate, opens the contact K1 and selects such a resistance value R6 at which the composite transistor VIV2 opens fully and bypasses the resistor R2. Then, the slider 11 is set to the position corresponding to the Average value of the normally used nominal feed rates, and the contact K1 is released. In this case, the capacitor C1 is charged through the resistance R3 with a negative voltage. The voltage squeezed from the R5 and R6 splitter tap and limited by the zener diode V4 is applied to the base of the V1V2 composite transistor, causing it to smoothly close. Thereby, rheostat R2 is smoothly introduced into operation, the voltage across the excitation winding of generator 2 also gradually decreases, and the feed rate decreases accordingly. The duration of the closing of the composite transistor VJV2, equal to the required duration of the reduction of the feed rate before the output of the pool from the front feed rollers, is

 of the main transistor VJV2, equal to the required duration of the reduction of the feed speed before the output of the complex from the front feed rollers,

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tantalizing the selection of the resistance value R3. After that contact K1. open and capacitor C is discharged until the voltage drops directly at the base-emitter 1V2 junction. During the initial discharge of the capacitor C1, the composite transistor VIV2 is closed and the feed rate is reduced by the amount determined by the rheostat R2. During the subsequent discharge of the capacitor GI, the composite transistor

VIV2 opens smoothly, the voltage across the excitation winding of generator 2 also increases smoothly and the feed rate increases accordingly. g The duration of the initial discharge of the capacitor C1, which is equal to the passage time of the vertex end of the log at a reduced feed rate from the photographic 7 to the back of the set, is set by selecting the resistance value R4 and the parameters of the Zener diode V4. The duration of the subsequent discharge of capacitor C1 is equal to

Nok 11 is set to the extreme right. In this case, the voltage going through the closed contact K1 is for a row of capacitor C1, the maximum (therefore, it is charged and discharged for a longer time), and the voltage switched by the emitter is the collector of the composite transistor V1V2 R6 to the base of this transistor and opening it is minimal. As a result of the interaction of the voltages entering the base, the composition

the transit time of the vertex end of the 15th transistor V1V2 from its collection at a smoothly increasing feed rate from the back side of the saws to the separation knives behind the frame guiding apparatus is set by selecting the resistance value R5. Then the slider of the potentiometer R1 is set to the leftmost position at which the voltage going through the closed contact K1 to the battery of capacitor C1 is minimal (therefore, it is charged and discharged for a shorter time), and the voltage switched by switching tter - composite transistor collector, and the current flowing through a resistance R6 to the base of this transistor and its otkrshayuschy, max. As a result, the duration of the time intervals corresponding to the closed state and the smooth opening of the transistor is reduced in proportion to the increase in the value of the nominal speed, the feed caused by moving the slider 1 from the previous position to the leftmost position. At the same time, the lengths of sawn logs at reduced and gradually increasing feed rates should remain the same as with the average value of the commonly used nominal feed rates. If this condition. is not observed, then the device is adjusted by adjusting the previously selected value of maintaining R1 resistance 50 and repeating (if necessary several times) other operations of the described tuning cycle. If the condition is met and at. maximum and with an average of the normally used nominal values of the feed rate, it is also observed for any of its other values, for example, at the minimum, when the creeper and capacitor C, the duration of time intervals corresponding to the closed state and the smooth opening of this transistor increase 20 are proportional to the change in the nominal feed rate caused by moving the slider 11 of the RI potentiometer to the specified position. Thanks to this, the lengths of the saw 25 do not log on the reduced and smoothly the current feed rates remain unchanged.

The device works as follows.

30 Slider 11 sets the nominal feed rate required when sawing logs of a certain diameter (bars of a certain thickness). While there is no next log 8 in the wasp of the front feed rollers of the sawmill, and beam 7 of the photosensor 4 is not blocked, contact K1 is closed and capacitor C1 is charged with a negative voltage.

40 The composite transistor is closed and the current to the excitation winding of the generator 2 is supplied through the resistor R2, i.e. the voltage on this winding is low and, therefore, the rotation of the feeders at 45 is slowed down accordingly. During the course of the top of the log 8 to the front feed rollers (Fig. 2), the beam 7 of the photo sensor 4 overlaps and the output to the relay coil K is energized, the contact K is open and the capacitor C1 starts to discharge. the V1V2 transistor starts to increase, however, at the beginning of this process it remains closed and the top of the log 8 is washed down at a reduced relative to the nominal feed rate. By the time the top of log 8 goes to

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Nok 11 is set to the extreme right. In this case, the voltage going through the closed contact K1 to the charge of the capacitor C1 is maximum (therefore, it is charged and discharged for a longer time), and the voltage switched by the transition emitter is the collector of the composite transistor V1V2 to the base of this transistor and opening it, minimal. As a result of the interaction of the voltages supplied to the base of the composite transistor V1V2 with its collector and capacitor C, the duration of the time intervals corresponding to the closed state and the smooth opening of this transistor increase in proportion to the change in the nominal feed rate caused by the shift of the slider 11 of the RI potentiometer specified position. Due to this, the lengths of the saw sections 5 and the log at a reduced and smoothly increasing feed speed remain unchanged.

The device works as follows.

0 Slider 11 set required when cutting logs of a certain diameter (bars of a certain thickness) nominal feed speed. As long as the next log 8 in the axis of the front feed rollers of the sawmill is not present, and the beam 7 of the photosensor 4 is not blocked, the contact K1 is closed and the capacitor C1 is charged with a negative voltage.

40 The composite transistor is closed, and the current to the excitation winding of the generator 2 flows through the resistor R2, i.e. the voltage on this winding is reduced and, therefore, the rotation of the feed shaft is 45 respectively slowed down. When the top of the log 8 enters the front feed rollers (fig. 2), the beam 7 of the photosensor 4 interrupts and from its output to the relay coil K receives power, the contact K opens and the capacitor C1 begins to discharge, the voltage - the transistor V1V2 starts to increase, but at the beginning of this process it remains closed and the sawn-off of the top of the log 8 is performed at a lower relative to the nominal feed rate. By the time the top of log 8 goes to 55

1458227

Claims (1)

The use of the proposed device improves its efficiency due to a more rational, than the prototype, smooth, rather than fast, one-step change in the feed rate when sawing the vertex and butt sections of logs (bars). Due to this, the sawing quality and / or productivity indicators 10 are improved. The reliability of the mechanisms of the saw-frame and the device itself also increases, since the dynamic loads on them also decrease the speed. filing reaches nominal- 15 Formula and inventions having become full width saws, as the capacitor C1 is discharged, the composite transistor VIV2 opens smoothly, the voltage on the excitation winding of the generator 2 also increases smoothly, which causes a corresponding increase in the feed rate. By the time the top of the log 8 enters the separation knives behind the frame-guiding apparatus, the composite transistor V1V2 will open completely, the voltage on the winding to excite the generator 2 will be equal to What is the value at which the main part of the log is sawn? 8. After crossing the butt The end of the axis of the photo-track 7 (Fig. 1 and 3), the photo-sensor 4 cpa6aTbiBaeT, the relay K1 releases, the contact K 1 is closed and the negative voltage through the resistance R3 charges the capacitor C1. one . In this case, the transistor V1V2 smoothly this is caused by a gradual decrease in the voltage on the excitation winding of the generator 2, which entails a corresponding decrease in the feed rate. By the time the complete butt end of the log 8 comes out of the front feed rollers, the transistor VIV2 is closed. Consequently, the voltage on the excitation winding of the generator 2, and thus the feed rate, becomes reduced relative to their nominal values: values by the value determined by the rheostat R2. At this feed rate, the front part of the comp. During the cutting of each successive log (beam), the considered cycle of the device is repeated A device for regulating the feed rate in the sawmill frames, including a generator-motor-type feed drive, a constant-voltage source connected through a resistor to the generator excitation winding and mounted on the front upper feed roller supports a photosensor with an output relay In order to improve the quality of sawn timber, the device is equipped with a potentiometer connected to the voltage source, connected to transition emitter - collector parallel to the rheostat transistor, voltage divider and capacitor, one of the plates of which is connected to the engine of the potentiometer, and the other with one of the taps of a voltage divider, the other tap of which is connected to the base of the transistor, with one of the extreme terminals of the voltage divider connected to the collector of the transistor, and the other, through the opening contact of the output relay of the photosensor, to the negative; to the local pole of the voltage source. FIG. g 0U9.S