JPS60191634A - Device for inspecting quality of regenerated sand for casting - Google Patents

Abstract

PURPOSE:To decide quickly and exactly the quality of regenerated sand of casting mold by processing the regenerated sand with a magnetic separator, weighing automatically the magnetized sand and non-magnetized sand and detecting the weight ratio thereof. CONSTITUTION:Regenerated sand 2 produced by burning away the binder sticking to the molding sand used for casting by fluidized roasting, etc. is supplied by a screw feeder 4 and a chute 5 to a magnetic separator 6 by which the sand is separated to magnetized sand and non-magnetized sand. The magnetized sand is dropped by a feeder 7 onto a belt conveyor 10 and the non-magnetized sand is dropped by a feeder 8 onto a belt conveyor 14. The weights of the magnetized sand and the non-magnetized sand are measured by load cells 11, 12 and 15, 16 provided to both belt conveyors 10, 14, and the inputted to a controller 17. The controller 17 calculates the ratio between the magnetized sand and the non- magnetized sand, decides the quality of the regenerated sand from the weight ratio thus obtd. and displays the same on a display device 27.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to recycled foundry sand, and more particularly to a quality inspection apparatus for recycled foundry sand.

BACKGROUND OF THE INVENTION Conventionally, molds for manufacturing castings have generally been made of foundry sand containing silica sand as a main component, to which a small amount of a binder or the like is added as necessary. In this case, in order to effectively utilize the foundry sand, the foundry sand that has been used in the production of castings is recovered, and the thus recovered IC foundry sand is subjected to a regeneration process such as fluidized roasting to remove binders, etc., and is thus recycled. The quality of the recycled foundry sand is judged, and based on the results, an appropriate amount of new sand or binder is added to the recycled foundry sand, and this is reused as recycled foundry sand. .

In this case, the quality of the reclaimed sand has conventionally been judged based on the hue of the reclaimed sand, ignition loss ω, phosphoric acid soluble content, silicon dioxide N purity, high prevalence, etc.

Judging quality by hue is simple, but in this judgment method, errors occur in quality judgment due to individual errors among inspectors, physical condition, etc. Also, since the difference in hue is small, it is difficult to judge quality. It is difficult to do D correctly and systematically. In addition, it is possible to standardize quality in terms of standards such as loss on ignition, phosphoric acid soluble content h4, pure traces of silicon dioxide, and mitsumaro, but the judgment procedure is complicated and requires chemical analysis. Due to this method, it is difficult to quickly judge the quality of recycled sand.

In view of the above-mentioned problems in the conventional method for determining the quality of reclaimed foundry sand, the present invention '8 etc. has conducted various experimental studies, and as a result, has developed a method for determining the quality of magnetic sand and non-magnetic sand separated by magnetic separation. With the ratio! There is a linear correlation between strength, which is one of the most important properties required for Type 8, and therefore the quality of recycled foundry sand can be determined by adjusting the ratio of magnetic sand to non-magnetic sand. We have found that it is possible to test and determine the

Purpose of the present invention The present invention utilizes the correlation described above, which was discovered as a result of an experimental (σ) investigation conducted by the inventors, to determine the quality of recycled sand for foundries in a standard way. It is an object of the present invention to provide a quality inspection device for recycled foundry sand that can quickly inspect the quality.

DESCRIPTION OF THE INVENTION According to the present invention, the above-mentioned object is to provide a quality inspection device for recycled foundry sand, and to distinguish between recycled foundry sand and non-magnetic sand. Separated by the magnetic separation means and the magnetic separation means! 1. A quality inspection device for recycled foundry sand, comprising a first weight measuring means for measuring the weight of magnetic sand, a second weight measuring means for measuring the weight of non-Ii sand separated by the magnetic separation means, etc. and a quality inspection device for recycled foundry sand, such as a magnetic separation means that divides the recycled foundry sand into magnetic sand and non-magnetic sand, and measures the weight of the recycled foundry sand to be separated by the magnetic separation means. and a second weight measuring means for measuring the weight of either magnetic sand or non-magnetic sand separated by the magnetic separation means. achieved by.

Functions and Effects of the Invention According to the present invention, in any of the above-mentioned configurations, the measured values of the first and second weight measuring means! Since the ratio of 1 & 1 part and non-magnetic sand can be determined, the linear correlation between the ratio of magnetic sand and non-magnetic sand and the strength of the &lf type can be used to determine the The quality of recycled sand can be inspected routinely and quickly, making it possible to easily and accurately judge the quality of recycled foundry sand. It is possible to accurately predict the optimum u1 of new sand and adhesive to be added to the sand.

Examples of the present invention J, Ru & J! Prior to explaining an example of the ME test for recycled sand for single-purpose reuse, we will examine the correlation between the ratio of magnetic sand in recycled sand for foundry use and the quality (flexural strength) of recycled sand for foundry use. Tests that were carried out as planned (explained with X).

Previously, 8 scales of recycled foundry sand No. 8 were prepared.Next, these recycled sands were sequentially passed through a magnetic separator (
E Ryo I! ! ! The strength of the magnetic field was set to 6.
The ratio of magnetic sand for each reclaimed sand (weight percent ψ of magnetic sand to magnetic sand and non-!i@sand) is set to 0,000,000 μs.
and for each recycled sand, 100 parts of recycled sand, 2.5 parts of 11 ft of phenolic tree, and 2
0.3F 5 parts, water 1.5 parts, calcium stearate 0
．． Resin-coated sand was formed by kneading at a mixing ratio of 1 part, and the resin-coated sand of I) was used to prepare a bending test piece (
10x 10x 60mm).1. The bending strength was measured based on 6910 for jxs+i. The measurement results are shown in Table 1 and FIG. 1 below.

The table shows the ratio of magnetic sand and bending strength.Ratio of magnetic sand to molding sand Breaking strength type (%) Soil clod ALL Recycled sand NO, 165,528,0 ' NO, 262,030, 9 ' No, 3 62 .0 30.0” No, 4. 95.0 19.0 ” No, 5 49.0 4.1.5 ” No, 6 49.5. 40.3 9 No, 7 47.0 -40.1' No, 8 83.5. 25.0 From Table 1 and Figure 1, it can be seen that there is a very large difference between the strength of molds formed with the coated sand and the ratio of magnetic sand obtained by magnetic separation when recycled foundry sand is used as sand coated with phenolic resin. It can be seen that there is a high correlation (correlation coefficient -0.96).From this,
Recycled foundry sand! By separating magnetic sand and non-li@sand through 11 selections and measuring the ratio of separated magnetic sand,
It is possible to very easily judge the quality of recycled sand on a regular basis, and furthermore, it is possible to accurately predict the appropriateness of the new sand and binder to be added to the recycled sand in order to ensure the required mold bullet hole. Understand what you can do.

Next, an embodiment of a quality inspection apparatus according to the present invention, which is configured to inspect the quality of recycled foundry sand using the above-mentioned correlation, will be described.

FIG. 2 shows one embodiment of the quality inspection device according to the present invention. 3 is a block diagram of the four control paths incorporated in the embodiment shown in FIG. 2. In these figures, reference numeral 1 indicates a hopper that stores recycled foundry sand 2 to be inspected for quality. The reclaimed sand 2 stored in the small brim 1 is supplied in a substantially constant flow layer to the magnetic separator 6 through a chute 5 by a scraper J feeder 4 which is rotationally driven by a motor 3. . rIt1 selection machine 6
Below is a feeder 7 for continuously measuring the weight of magnetic sand and non-magnetic sand separated by the magnetic separator.
and 8 are provided. The weighing feeder 7 is provided between a belt conveyor 1° driven by a motor 9 and a driving pulley and a driven pulley of the belt conveyor in a position close to them, and is a vertical feeder that acts on an idle roller (not shown in the figure). A pair of 0-
11 and 12. Similarly, the weighing feeder 8 is connected to a belt conveyor 14 driven by a motor 13.
The belt conveyor 14-L is detected by detecting the vertical load acting on an idle roller (not shown in the figure), which is located between and close to the driving bobbin and driven pulley of the belt conveyor. It has a pair of load cells 15 and 16 for measuring the weight of non-magnetic sand.

The magnetic selector 1116 does not indicate the strength of its magnetic field and sends a signal to the controller 1.
It is designed to output to load cells 11 and 1.
2, [1-Docels 15 and 16 are magnetic sand and non-! As shown in FIG. 3, a signal indicating the weight of the magnetic sand at each moment is outputted to the control I device 17.
The control device 17 includes a microphone [] combination coater 18, and the microcomputer 18 controls the input port 1 to the device 19.
, random access memory (RAM>20, read-only memory (ROM) 21, and central processing unit (C
It is a general type in which the P(J) 22 and the output boat device 23 are connected to the right, and information regarding the strength of the internal magnetic field is conveyed from the magnetic separator 6 by the belt conveyor 10 from the load cells 11 and 12. The load cells 15 and 16 provide information regarding the weight of the magnetic sand at each moment, and information regarding the weight of the magnetic sand at each moment conveyed by the belt conveyor 14 to the input boat device 19. Take this information into the RAM 20 and CPU 22,
Based on the program and data stored in the ROM 21, the output boat device 23 outputs control signals to the display device 27, the new sand supply system 28, and the resin supply system 29 through drive circuits 24 to 26, respectively.

The microcomputer 18 operates at predetermined intervals (for example, 0.5
Within the CPU 22 (every second), the measured values of the weight of the magnetic sand detected by the 0-docels 11 and 12 x1 and x
From 2, calculate the average value ×−(×1+x,,)/2,
Also, the non-! From the measured weight of magnetic sand ■1 and σy2, the average value v-(y
+y2〉/2 is calculated, and their average values are sequentially stored in RAM.
20, calculate the total value z = x + y, and further derive the weight ratio R-X'/Z of magnetic sand to magnetic sand and non-magnetic sand from the average value X and total value l. , an output signal based on the calculation result is outputted to the drive n path 24, whereby the display device 27 displays the value of the weight percentage of magnetic sand with respect to sand and non-magnetic sand at predetermined time intervals. It is as shown below.

Further, in the illustrated embodiment, the microcomputer 18
The ROM 21 stores in advance the optimum amount of new sand and resin to be added according to the ratio R and the magnetic field strength of the magnetic separator 6 as a two-dimensional map with the ratio R and the magnetic field strength of the magnetic separator 6 as variables, and the microcomputer 18 Addition of new sand and resin according to the two lr control variables based on the conversion rate R calculated by the CPU 22 and the strength of the magnetic field input from the magnetic separator 6.
The data value is read from the ROM 21, and the data value is outputted to the output capacitor 1 via the device 23 and drive circuits 25 and 26 to the new sand supply system 28 and resin supply system 29, respectively.

The quality inspection apparatus configured as described above operates as follows. In other words, the hopper 1J is fed by the Scrico feeder 4.
- Recycled sand 2 is supplied to t6 at a substantially constant flow, and the recycled sand is continuously deposited into Ii by a magnetic separator set at a constant magnetic field strength. The weights of the magnetic sand and non-magnetic sand are measured at each instant by the load cell 11.12 and the load hill 15.16. The weight ratio of magnetic sand to Ik%i sand and non-magnetic sand is calculated by the microcoater 18 of the control device 17 based on the measured value and the signal of the magnetic field strength of the magnetic separator, and is displayed based on the weight ratio. Magnetic sand and non-magnetic sand in the device 27! The weight percentage of the magnetic sand to the magnetic sand is displayed as the quality test result of the recycled sand, and based on the weight ratio, an optimal amount of new sand and resin necessary and sufficient to ensure the required mold strength is added to the recycled sand. A control signal is output to the new sand supply system 28 and the resin supply system 29 so that

FIG. 4 is a schematic configuration diagram similar to FIG. 2 showing another embodiment of the quality inspection apparatus for recycled foundry sand according to the present invention. In FIG. 4, members that are substantially the same as those shown in FIG. 2 are designated by the same reference numerals.

In this embodiment, the belt conveyor 14 is not provided with a load cell, but a straddling feeder 30 is disposed between the chute 5 and the magnetic separator 6. Measuring feeder 3
0 is driven by the motor 31 and shoots 5 in one breath.
A belt conveyor 32 transports recycled sand received from the sand and charges it into the magnetic separator 6 from the other end via a chute 5a, and a belt conveyor 32 which is disposed close to the driving pulley and driven pulley of the belt conveyor. A pair of D-drels 33 and 371 are used to measure the If of reclaimed sand on the belt conveyor 32 by detecting a vertical load acting on an idle roller (not shown).

Like the load cells 11, 12 and 15 and 16, the load cells 33 and 34 are designed to output a signal indicating the weight of the reclaimed sand conveyed by the belt conveyor 32 to the control device 17.

The control device 17 in this embodiment may be the same as the control device 11 shown in FIG.
and 34.

In the quality inspection according to this embodiment, the measured values Zl and 12 from the road hills 33 and 34 are measured by the 0PU22.
Based on the average value of the weight of reclaimed sand l = (Zl +22
＞/2 is calculated, and the weight of magnetic sand with respect to magnetic sand and non-magnetic sand is calculated from the average value 2 and the average value X of the weight of magnetic sand calculated as in the example described in -F. Ratio R'=X/Z
is calculated, and based on that value, the weight percentage of magnetic sand to magnetic sand and non-magnetic sand is displayed on the display device 27, and based on the value, new sand is added to the new sand supply system 28 and the two resin supply systems, respectively. A control signal indicating the optimum value of the amount and the amount of resin added is output.

In any of the above-mentioned embodiments, the quality of the recycled foundry sand is continuously inspected, and the amounts of new sand and resin added to the recycled foundry sand are continuously controlled. However, the quality inspection device according to the present invention may also be configured to operate in batch mode.

For example, a sensor is provided to detect the sand conveying speed tη of the corresponding belt conveyor by detecting the rotational speed of one of the pulleys of each motor or each belt conveyor, and the measured values of these sensors and the date cell 11 and 12.
15 and 16. Measurement according to 33 and 34 1 "By calculating the product with 1 and integrating the value as a function of time, total weight of magnetic sand x 1 total weight of non-magnetic sand Y, recycled sand Calculate the total weight Z of
It may be configured to calculate as -x/Z.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to such embodiments, and it is understood that various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art. For example, the ratio of magnetic sand to non-magnetic sand is the ratio of non-magnetic sand to magnetic sand and non-magnetic sand, the ratio of non-magnetic sand to magnetic sand of 4, or the ratio of non-magnetic sand to magnetic sand of 4. It may be the ratio of magnetic sand.

[Brief explanation of drawings]

Figure 1 shows the four types of recycled sand. A graph showing the relationship between the 1-sand zero ratio and the bending strength. Fig. 2 is a schematic configuration diagram showing one embodiment of the quality inspection device for recycled foundry sand according to the present invention. FIG. 2 is a block diagram showing the control circuit in the embodiment shown in FIG. 2, and FIG. FIG. 2 is a schematic configuration diagram similar to that of FIG. 1...Hopper, 2...Recycled foundry sand, 3...Motor. 4...Screw feeder, 5...Chute, 6...
・1 Electric separator, 7.8...Measuring feeder, 9...Motor, 10...Belt conveyor, 11.12...0-
1, 13...Motor, 14...Belt conveyor, 15.16...Load cell, 17...Control device, 18...Microcomputer, 19...Input boat device 20... Random access memory (RAM)
), 21... Read only memory (ROM), 22.
...Central processing unit (CPU), 23...Output boat device, 24-26...Drive circuit, 27...Display device, 28...New sand supply system. 29...Resin supply system, 30...Measuring feeder, 31
...Motor, 32...Belt conveyor, 33.34
...Load cell patent applicant Toyota Motor Corporation Representative Patent Attorney Masatake Akashi 1 Figure 3 / 22nd Section [System] ul -) 1 circuit (11 people out n ll' +1. ” Ka 2o Ka...
7"l F?OM l...3□, 7,1 Den-do Po
・ 1 ・ 721 1261'Ill Fig. 2

Claims (2)

[Claims] (1) A quality inspection device for recycled foundry sand is equipped with a magnetic separation means for separating recycled foundry sand into magnetic sand and non-magnetic sand, and a weight of the magnetic material separated by the magnetic separation means. A quality inspection device for reclaimed foundry sand, comprising a first weight measuring means for measuring, and a second lhj measuring means for measuring the weight of non-magnetic sand separated by the magnetic separation means. (2) Recycled foundry sand product ff4I! A magnetic separator for separating recycled foundry sand into tit sand and non-magnetic sand is installed in the apricot device. A quality inspection device for recycled foundry sand, comprising a weight measuring means, and a second weight measuring stage for measuring the weight of either magnetic sand or non-magnetic sand separated by the magnetic separation means.