SU523301A1 - Control unit for weighing batch dosing - Google Patents

Description

one

The invention relates to the field of weighing technology.

The known control devices are weight batch dispensers containing a resolver associated with the axis of the dial gauge pointer, unit adjuster, control unit 1-5.

The closest in technical essence to the proposed device is device 6, which contains a weight mechanism with a resilient sensor, the rotor of which is connected to the axis of the dial gauge pointer, the three-phase winding of which is connected to the coding unit, which determines the mass of the portion, and the single-phase winding a demodulator connected to coarse and precise metering triggers connected via OR elements to coarse and accurate metering signal generators.

In the known device, the dose setting is performed by applying a specific voltage combination to the three-phase windings of the selsyn sensors. Such devices do not provide the required accuracy of dose setting. They lack the remote indicator of the weight measurement result, as a result of which it is impossible to maintain operational control over the dosing process. In addition, these devices do not provide prompt information about the accuracy of the weighed dose. The presence of a constant coarse weighing threshold increases the number of switches in the control valve of the metering valve, which reduces the reliability of the dosing system as a whole.

To improve accuracy and reliability, the proposed device is equipped with a counting pulse generator, a pulse gate driver, two selectors, a pulse counter, an indicating device and a coarse plumb self-regulating threshold unit, and the control unit and the control node are digital. sensor, and the output is connected to the control input of the selector, which connects the counting pulse generator with a pulse counter, and to the control input of the selector, in binding generator countable imnulsov with the control node connected to the threshold unit samoreguliruyuschegos coarse and plumb with setpoint.

The drawing shows a block diagram of the described device.

The axis of the arrow 1 of the dial indicator is connected to the rotor of the selsyn sensor 2, which is connected to the gate generator 3. Pulse counter 5 is connected to the selector 4, the output of which is connected to the indicating device 6. A node is connected to the selector 7

control 8 associated with the digital setting device 9 and with the block 10 of the self-adjusting coarse plumb threshold. The generator 11 counting pulses connected to the inputs of the selectors 4 and 7. The device operates as follows. The angular position of the arrow 1 is transmitted to the rotor of the selsyn sensor 2, which is powered from a multiphase voltage source (not shown). The voltage removed from the stator winding of the selsyn sensor will be shifted to the phase relative to the voltage on one of its rotor windings by an angle perpendicular to the angle of rotation of the arrow 1. The strobe pulse generator 3 forms a sequence of square pulses, the duration of which is determined by the phase pulse shift of the voltage of the phase shifter.

Counter 5 measures the pulse duration and gives the result of counting to the indicating device 6. The parameters of the measuring channel are chosen so that the device 6 gives information in terms of the weight of the components to be dosed.

The selector 7 and the generator of the counting pulses 11 form a time sequence of pulses corresponding to the current value of weight. In the digital control unit 8, the number of these pulses is compared with the pulses of the digital setter 9. Upon reaching the weight equal to the set value, the unit 8 generates a signal to stop metering. At the same time, the time relay will be turned on in block 10, adjusted to the time required to calm the weight mechanism. At the end of the settling down time, unit 10 of the self-adjusting coarse plumb threshold outputs to the digital control node 8 a polling signal of the magnitude of the actual weight taken.

If the weight taken is greater than or equal to the pre-selected on digital setting device 9, then a signal is given to end the dosing. If the weight taken is less than the required one, then in block 10 an accurate dosing trigger is activated, making the dosage in portions. Moreover, the trigger will work until the weight taken does not correspond to the specified one. The self-adjusting norm of the coarse plumb, as opposed to the permanently set, allows the exact operation time of the exact dosing trigger to be automatically changed depending on

on the dynamics of the process of weighing the components. In the process of dosing, the coarse plumb threshold can be reduced to zero if the flow rate of a component approaches the calculated one, or becomes less than it. As a result, the wear of the dispenser mechanisms is drastically reduced and the reliability of the system is increased.

The proposed device eliminates unnecessary shutdowns of the system at the gross weight level at the estimated flow rate of components at a time when a given portion can be weighed out without activating the exact weight trigger.

Claims (6)

1.Avt. St. LI 311147, G Olg 13/28, 03/18/70. 2. Avt. St. No. 337659, G Olg 23/26, 05.05.72. 3. The patent of Germany No. 1574662, 42f 23/26, 06.09.73. 4. The patent of France No. 1556300, G Old 13/00, 30.12.68. 5. E. Karpin. "Automation equipment for measuring and metering the mass," Mechanical Engineering, 1971. 6.Avt. St. No. 347587, G Olg 13/28, 11.05.70.