SU768648A1 - Apparatus for producing lime-sand moulding mixture - Google Patents

Description

1 ..- The invention relates to the production of building materials, in particular to the production of products from a lime-sand mixture, for example silica brick or slab.

A device is known for primary-Lenin molding sand containing a mixer with loading and unloading mechanisms and a current meter consumed by the electric motor driving the mixer 1.

However, such a device does not provide the optimum wetting of the mixture, since the current of the mixer motor drive with a small degree of accuracy: 1%, which characterizes the plasticity of the mixture.

It is also known a device for the preparation of lime-sand mixture containing a mixer with feed and discharge conveyors, a supply line for WATER with a regulating organ, a receiving bin, a source. .. power supply, control unit and element compared to 25 and 2.

A disadvantage of this device is the poor quality of the mixture, since it does not take into account the time it takes to transport the mixture to the receiving bin. ZO

The purpose of the invention is to improve the quality of the preparation of the mixture.

This is achieved by incorporating a tachogenerator installed on the unloading conveyor, counter into the device for preparing lime sand-sand molding mixture containing a mixer with feed and discharge conveyors, a WATER supply pipeline with a regulator, a receiving hopper, a power source, a gauge and a reference element. pulses interrupter, threshold element, phase-sensitive amplifier, secondary device, transducer and humidity sensor installed in the receiving bin and made in the form of a rod mounted inside the ring using dielectric specials, just as the humidity sensor is connected to one of the converter inputs, to the D1 input of which the power supply is connected, the output of the converter through the secondary device is connected to one of the comparison inputs, to the other input of which the setting device, output of the comparison element through a cut-out series-connected laser-sensitive amplifier and threshold element are connected to one of

the inputs of the chopper, the other input of which is connected through a pulse counter to the tachogenerator, and the output of the chopper is connected to the regulator.

FIG. 1 shows a diagram of the described device; FIG. 2 - humidity sensor.

The device contains a mixer 1 with supply 2 and discharge 3 conveyors, pipe 4 with a regulating body 5, a moisture sensor b of the mixture connected to a converter 7 connected to a power source. 8 and a secondary device 9 connected to the element 10, to which the control device 11 is connected, the tachogenerator 12, connected with the counter Pulses 13, the output of which is connected to the breaker 14, together with the threshold element 15 and the phase-sensitive amplifier 16 connected in series. element of comparison 10 and the regulatory authority 5. The sensor 6 is installed in the receiving hopper 17 of the press 18, the shape of the product.

Structurally, the sensor b (cf.fig.2) is made in the form of a rod 19, covered with insulating material 20, for example rubber, supplied with a cone 21, and a concentric metal ring 22, for example, of a copper bus, which is made of dielectric material 23 is connected to the rod 19. The ring 22 and the rod 19 are interconnected by a winding 24, which in the primary converter 7 is inductively connected to the winding 25 connected to the power source B, which is a common frequency generator.

The device works as follows. -.

Lime-sand mixture of silage. (not shown) through conveyor 2 enters mixer 1. In it, it additionally moves (to average composition) and is moistened. Humidification occurs in such a way that the mixture is well molded in the press 18 and at the same time does not contain excessive moisture, negatively affecting the quality of the manufactured products, such as tiles.

The optimum degree of moisture content of the mixture, determined by experimental laboratory means, is set at the setting unit 11, the signal from which is sent to one of the inputs of the reference element 10. From the mixer 1 The molding mixture enters the receiving hopper 17 of the press 18, where the sensor 6 determines its moisture. From sensor 6, a high-frequency signal proportional to the humidity of the cell through the primary converter 7 is fed to the input of the secondary device .9, where it is converted into a form.

similar to the signal of the setting device 11, for example, to the low frequency voltage or to the resistance. On the element of comparison 10, the signals from the setting device 11 and the secondary device 9 are compared with each other, and their difference is supplied through the phase-sensitive amplifier 1, which determines the sign of the error, to the threshold element 15. The threshold element 15 transmits the error signal to the interrupter 14 only if it characterizes the deviation of the moisture content of the mixture by an amount greater than the allowable deviation zone, for example ± 0, 5%. The interrupter 14 is controlled by a pulse counter 13, counting the pulses coming from the tachogenerator 12, fixing, moving the mixture by the conveyor 3 for a predetermined distance. For example, if, when moving the material by the conveyor 3 from the mixer 1 to the receiving bin 17 tah6gene) ator 12, it produces 1000 pulses, then the counter 13 adjusts to the same number of pulses. When a specified number of pulses arrive at the counter 13, it triggers and sends a command in the form of a pulse of a certain duration to the interrupter 14, which opens. As a result, the error signal from the reference element 10 is supplied to the regulator body 5, which, due to the pulsed nature of the signal, only slightly opens or closes. This eliminates the possibility of overshooting due to transport lag. Sledgadiy signal to the regulator 5 comes in if the moisture content of the material remains outside the normal range, after transporting 1 and a portion of the material (affected by water consumption) from mixer 1 to hopper 17, etc. Thus, the regulation of the wetting of the mixture is performed stepwise, thus achieving a smooth mono-toning approach to optimum irrigation, eliminating over-wetting and under-wetting of the material as a result of jumps in its initial humidity.

The operation of the device’s humidity sensor 6 is based on a change in the electrical conductivity of the mixture to high frequency currents depending on its moisture content.

The high frequency signal from the power source 8 enters the circuit, including a winding 24, a rod 19, a ring 22 and a mixture filling the space between the rod 19 and the ring 22, the dimensions of which are selected in accordance with the size of the receiving hopper.

For a better flow of high-frequency current into the mixture, a cone 21 serves. The resistance of said circuit from

Claims (1)

Claim A device for preparing a sand-and-sand molding mixture containing a mixer with feed and discharge conveyors, a water supply pipe with a regulatory body, a hopper, a power source, a setter and a comparison element, characterized in that, in order to improve the quality of preparation of the mixture, it is introduced tachogenerator installed on the unloading conveyor, pulse counter, chopper, threshold element, phase-sensitive amplifier, secondary device, converter and humidity sensor installed in the receiving hopper and made in the form of a rod mounted inside the ring using dielectric spokes, moreover, the humidity sensor is connected to one of the inputs of the converter, to the other input of which a power source is connected, the output of the converter through a secondary device is connected • to one of the inputs of the element * ^υ Nia, the other input of which is connected dial, comparison 'Nia vepe3 output element serially connected phase-sensitive amplifier and the threshold element 15 is connected to one of the inputs of the interrupter, the other Rin d / which is connected through a pulse counter with a tachogenerator, and the output connected to the chopper regulator.