JPS6145004B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for managing aggregate supply in an asphalt plant for producing asphalt mixture.

Conventionally, when cutting aggregate from a group of hoppers that store aggregate of various particle sizes and supplying the aggregate to a dryer, which is a heating device, the amount of aggregate cut from each hopper was determined by the mixing ratio of the asphalt mix to be manufactured. Based on the plant shipping capacity, the cutting amount of the variable speed aggregate cutting feeder installed below each hopper is roughly set at the beginning of operation, and the aggregate feeding amount is detected during the aggregate feeding process. Since no means have been established, the actual amount of aggregate supply is not known. However, the dryer, which is a heating device, has an aggregate supply amount that provides the best heating efficiency, and from the perspective of energy saving, it is preferable to maintain the optimum supply amount at all times. If the amount of aggregate supplied fluctuates, the combustion amount of the burner will also fluctuate, but burner combustion control is usually a follow-up control that is performed by detecting the temperature of the heated aggregate discharged from the dryer. Constant fluctuation in the amount of combustion causes temperature unevenness in the heated aggregate, which is not desirable in terms of quality control of asphalt mixture.

In view of the above points, the present invention provides a weighing conveyor in the middle of conveying aggregates cut out from a group of hoppers storing aggregates according to various particle sizes and conveyed to a dryer, detects the instantaneous flow rate of aggregates, and An asphalt plant structure that calculates the amount of deviation compared to the set material supply amount, corrects the cutting amount of each hopper based on this deviation amount, and always keeps the amount of aggregate supplied to the dryer constant. The present invention provides a material supply management device.

Embodiments of the present invention will be described below based on the drawings. Fig. 1 is a system diagram of the aggregate supply management device of the present invention, where 1a, 1b...1f are hoppers for storing aggregate according to various particle sizes, and below the hopper is a hopper for cutting out the aggregate. Variable speed feeder 2a, 2b
...... 2f is provided, and the feeders 2a, 2
b...The aggregate cut out at 2f is conveyed by a conveyor 3 and supplied to a dryer 5 via a weighing conveyor 4. The above hopper 1a, 1b……1
The aggregate f is cut out as follows.

First, the asphalt mixture to be manufactured, for example, whether it is coarse-grained asphalt or dense-grained asphalt,
Also, each hopper 1 depending on whether it is a modified topeka etc.
Since the aggregate cutting ratios of a, 1b...1f are different, the changeover switch 7 of the aggregate supply mixing ratio setting section 6
By the switching operation, the cutting ratio of the asphalt mixture is appropriately selected. This aggregate supply mixing ratio setting section 6 sets the aggregate cut-out ratio of each feeder 2a, 2b...2f when producing several types of asphalt mixtures such as coarse-grained Asphalt, dense-grained Asphalt, and modified Topeka. It is set. Next, set the desired aggregate supply amount (TON/H) in the aggregate supply amount setting section 8, which sets the total supply amount of aggregates of various particle sizes to be supplied to the dryer 5, and press the aggregate supply start button. By pressing the button, the output signals of the aggregate supply mixing ratio setting section 6 and the aggregate supply amount setting section 8 are inputted to the calculation section 9, and the output signals of the aggregate supply mixing ratio setting section 6 and the aggregate supply amount setting section 8 are inputted to the calculation section 9, and
From each hopper 1a, 1b......1f by calculating the set voltage to be applied to each motor transmission device 10a, 10b...10f that outputs a speed command to 2b...2f and outputting a voltage signal. A desired amount of aggregate is cut onto a conveyor 3 and fed to a dryer 5 via a weighing conveyor 4. The weighing conveyor 4 is equipped with a load cell 11, which is a vertical load detector that detects the weight of conveyed aggregate, and a belt speed detector 1.
2 is provided to input the speed pulse signal output from the belt speed detector 12 to the frequency/voltage converter 13, convert it into a voltage, and apply the output speed voltage signal as the voltage to the load cell 11. extracts the output signal of instantaneous aggregate flow rate from the load cell 11 and inputs this output signal to the comparator 15 via the amplifier 14, as well as the aggregate supply amount indicator 16 on the operation panel and the aggregate supply tonnage counter. 17, and the aggregate instantaneous flow rate (tons/H) is input to the aggregate supply amount display 16, and the total tonnage of aggregate supplied to the aggregate supply tonnage counter 17 is displayed.

The comparison section 15 calculates a deviation amount by comparing the aggregate supply setting amount inputted from the aggregate supply amount setting section 8 and the instantaneous aggregate flow rate detected by the load cell 11, and calculates the deviation amount signal. is input into the calculation unit 9 and the aggregate supply mixture ratio is preset in the aggregate supply mixture ratio setting unit 6, and each hopper 1A, 1b...
...Calculate the cutout correction amount of 1f, and apply this correction voltage signal to the motor transmission devices 10a, 10b...10
By correcting the amount of aggregate cut out from each feeder 2a, 2b, . Reference numeral 18 denotes a correction width setting device, and when the calculation unit 9 calculates the cutting correction amount for each hopper 1a, 1b, . Since the amount of material to be cut out may become too large, an allowable correction width is set, and if the correction amount calculated by the calculation section 9 exceeds this set value, the alarm lamp 19 will flash to issue an alarm. That's what I do. Further, each feeder 2a, 2b...2f is provided with a flow rate sensor 20a, 20b...20f, so that an alarm lamp 19 flashes to issue an alarm when no aggregate is being cut out.

As described above, the present invention uses the measuring conveyor 4 to detect the instantaneous flow rate of aggregate cut out from a group of hoppers that store aggregate according to various particle sizes, and compares it with a preset aggregate supply amount to determine the amount of deviation. The amount of cut-out of each hopper 1a, 1b, . The amount of aggregate supplied to the furnace does not fluctuate, and the best heating efficiency is always maintained, saving energy. At the same time, there is little fluctuation in the amount of burner combustion, which eliminates uneven temperature of the heated aggregate, improving the quality of asphalt mixture. is what one can hope for.

The present invention can be employed not only in asphalt plants that produce new asphalt mixtures, but also in recycling plants that regenerate asphalt waste materials.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an embodiment of the present invention. 1a, 1b...1f is hoppa, 2a, 2b...
... 2f is a feeder, 3 is a conveyor, 4 is a weighing conveyor, 5 is a dryer, 6 is an aggregate supply mixing ratio setting section, 8 is an aggregate supply amount setting section, 9 is a calculation section,
10a, 10b...10f is a motor transmission device,
11 is a load cell, 12 is a belt speed detector, 1
5 is the comparison section.

Claims (1)

[Claims] 1. A group of hoppers that store aggregate according to various particle sizes, a variable speed feeder for cutting aggregate installed below the hopper, and supplying the aggregate cut by the feeder to a dryer that is a heating device. In an aggregate supply device for an asphalt plant consisting of a transport conveyor, an aggregate supply mixture ratio setting unit sets various aggregate supply mixture ratios according to the type of asphalt mixture; a material supply amount setting section; a calculation section that calculates the amount of aggregate to be cut out of each hopper from the set values of the aggregate supply mixing ratio setting section and the aggregate supply amount setting section; a weighing conveyor, which is equipped with a means for controlling the amount of cut-out of the feeder, and is also equipped with a vertical load detector and a belt speed detector during aggregate conveyance; a comparison section that calculates a deviation amount by comparing it with the aggregate supply setting amount set in the material supply amount setting section; a calculation unit that calculates the correction amount of aggregate cut-out of each hopper based on the material supply mixing ratio; and a means for correcting the amount of aggregate cut-out of each feeder based on the correction amount of aggregate cut-out output from the calculation unit. An aggregate supply management device for an asphalt plant characterized by the following.