DE112019003025T5 - Mold forming device, mold quality evaluating device, and mold quality evaluating method - Google Patents

Abstract

[Problem]: To provide a mold molding apparatus, a mold quality evaluation apparatus and a mold quality evaluation method capable of evaluating the quality of a molded green sand shape without measuring a green sand mold using a mold strength gauge every time a green sand mold is in Solution: The problem is solved by including: a green sand mold forming sensor that measures a pressure value applied to a connection portion between green sand filled in a mold forming space and a pressure plate or a pressure foot during molding of a green sand mold; and a mold quality evaluation device that evaluates the quality of a green sand molded shape from the pressure value.

Description

TECHNICAL AREA

The present invention relates to a mold forming apparatus, a mold quality evaluation apparatus, and a mold quality evaluation method which evaluates the quality of a green sand molded shape.

BACKGROUND

One of the indicators for evaluating the required quality of a green sand mold (casting mold) molded by a mold forming apparatus is mold strength. To determine whether a molded green sand shape has sufficient mold strength, work is usually done on each molded green sand shape individually measured using a mold strength gauge. A method of confirming whether a green sand molded shape has sufficient mold strength without performing such work is desired. Furthermore, a method of managing the mold quality of each molded green sand shape without stopping a process is desired.

For example, Patent Document 1 discloses a method of detecting abnormalities in injection and loading of casting sand in a blow-in type mold molding machine, wherein an internal pressure is measured by a pressure sensor to detect abnormalities in injection and loading of casting sand.

Further, Patent Document 2 discloses a casting apparatus monitoring system that detects defective molds using position transmitters for measuring positions of piston adjusting cylinders, filling piston cylinders, and a leveling frame for monitoring the height of a parting plane of a casting mold.

QUOTE LIST

PATENT LITERATURE

• Patent Document 1: JP 3415497 B
• Patent Document 2: JP 3729197 B

SUMMARY OF THE INVENTION

TECHNICAL PROBLEM

However, the method for detecting abnormalities in injection and loading of casting sand of Patent Document 1 is only capable of detecting sand loading defects, and it is difficult to confirm the precise mold strength. Further, even if the molding device monitoring system of Patent Document 2 monitors the height of the parting plane of the mold, it is difficult to confirm the precise mold strength from the height of the parting plane.

The present invention has been made in view of the above, and has as an object to provide a mold forming apparatus, a mold quality evaluation apparatus and a mold quality evaluation method which can determine the quality of a molded green sand mold without measuring a green sand mold with a mold strength gauge for each in one Piston shaped green sand mold can evaluate.

TROUBLESHOOTING

In order to solve the above-mentioned problem and achieve the object, the mold forming apparatus of the present invention comprises: a green sand mold forming sensor that measures a pressure value applied to a contact portion between a pressure plate or pressure feet and green sand during molding of a green sand mold which is inserted into a mold forming space; and a mold quality evaluation device which estimates the quality of the molded green sand mold from the pressure value.

Further, in one embodiment of the present invention, the mold quality evaluation device comprises a mold strength calculating unit that calculates the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured.

Further, in one embodiment of the present invention, the mold quality evaluation device includes a mold quality determination unit that determines the quality of a molded green sand mold from the calculated mold strength based on a predetermined threshold value.

Further, in one embodiment of the present invention, the mold strength calculating unit calculates the mold strength of a green sand mold for which the mold strength has not been measured.

Further, in one embodiment of the present invention, the mold quality evaluation device further comprises display means that displays a relationship between the pressure value calculated by the mold strength calculating unit and the mold strength of a green sand mold for which the pressure value was measured.

Further, in one embodiment of the present invention, the mold quality evaluation apparatus further comprises recording means that records pressure value data, mold strength data associated with the pressure value, a calculation result of the mold strength, and a determination result of the mold quality generated during molding of a green sand mold.

Further, in an embodiment of the present invention, transmission of a pressure value from the green sand mold forming sensor to the mold quality evaluation device is carried out via wireless communication.

Further, in an embodiment of the present invention, the mold forming apparatus is a flaskless molding machine or a flask molding machine.

Further, in an embodiment of the present invention, the pressure plate is configured to be rectangular, an arrangement of the pressure feet is configured to be rectangular, a plurality of green sand mold shape sensors are provided, and these pressure sensors are attached to the four corners of the pressure plate or in the pressure feet embedded in the four corners.

Further, during molding of a green sand mold, the mold quality evaluation device of the present invention evaluates the quality of a molded green sand shape from a pressure value applied to a contact portion between a pressure plate or a pressure feet and green sand filled in the mold molding space.

Further, in one embodiment of the present invention, the mold quality evaluation device includes a mold strength calculating unit that calculates the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured.

Further, in one embodiment of the present invention, the mold quality evaluation device includes a mold quality determination unit that determines the quality of a molded green sand mold from the calculated mold strength based on a predetermined threshold value.

Further, the mold quality evaluation method of the present invention comprises measuring, while molding a green sand mold, a pressure value applied to a contact portion between a pressure plate or press feet and green sand filled in a mold molding space, and evaluating the quality of a molded green sand mold from the pressure value.

Further, in one embodiment of the present invention, evaluating the quality of a green sand mold includes calculating the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured.

Furthermore, in one embodiment of the present invention, evaluating the quality of a green sand mold comprises determining the quality of a molded green sand mold from the calculated mold strength on the basis of a predetermined threshold value.

EFFECTS OF THE INVENTION

According to the present invention, there is exhibited an effect in which it is possible to individually calculate the mold strength of molded green sand molds without measuring using a mold strength gauge, and further to evaluate the quality of the green sand mold.

Figure list

• 1 FIG. 13 represents a diagram of a structure of a mold forming apparatus according to a first embodiment.
• 2 represents a configuration of a portion of a mold forming apparatus, the portion evaluating the mold quality.
• 3 Figure 13 is a cross-sectional view representing details of a portion of a printing plate having green sand shape shape sensors embedded therein.
• 4th Figure 13 is a cross-sectional view representing details of a portion of a printing plate having green sand shape shape sensors embedded therein.
• 5 Fig. 13 is a block diagram representing an example of a functional configuration of a mold quality evaluation device.
• 6th Fig. 13 is a block diagram representing another example of a functional configuration of a mold quality evaluation device.
• 7th Fig. 13 is a schematic view representing a configuration of an experiment carried out herein, wherein (a) is a cross-sectional view, and (b) is a plan view of a pressure plate.
• 8th Fig. 13 is a graph representing an example of results obtained by recording, in an integrated amplifier recorder, lateral changes in pressure of a green sand shape forming sensor in a squeezing step and analyzing by computer.
• 9 Fig. 13 is a graph summarizing a relationship between peak pressure of a green sand mold forming sensor and mold strength.
• 10 Fig. 10 shows an example of a screen displayed on a display unit.
• 11 Fig. 10 shows an example of a screen displayed on a display unit.
• 12th Fig. 10 shows an example of a screen displayed on a display unit.
• 13th Fig. 13 shows steps in a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus according to the first embodiment.
• 14th Figure 12 shows another example of a printing plate having green sand mold shape sensors embedded therein.
• 15th Figure 12 shows another example of a printing plate having green sand mold shape sensors embedded therein.
• 16 FIG. 13 represents a diagram of a structure of a mold forming apparatus according to a second embodiment.
• 17th represents a configuration of a portion of a mold forming apparatus, the portion evaluating the mold quality.
• 18th Fig. 13 shows steps in a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus according to the second embodiment.
• 19th Figure 12 shows another example of a printing plate having green sand mold shape sensors embedded therein.
• 20th Figure 12 shows another example of a printing plate having green sand mold shape sensors embedded therein.
• 21 FIG. 13 represents a diagram of a structure of a mold forming apparatus according to a third embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, reference will be made to the accompanying drawings to describe embodiments for implementing the mold forming apparatus, the mold quality evaluating apparatus, and the mold quality evaluating method according to the present invention.

(First embodiment)

The first embodiment will be described with reference to the accompanying drawings. 1 represents a diagram of a structure of the mold forming apparatus according to the first embodiment, and FIG 2 represents a configuration of a portion of the mold forming apparatus, the portion evaluating mold quality. The mold molding apparatus according to the present embodiment is a flask molding apparatus in which, after a green sand mold (mold) is molded, a mold box (metal mold box) with the green sand mold contained therein is transferred to the next step.

A mold forming device 1 includes a plate 2 with a pattern 3 attached to an upper surface thereof, a bracket 4th , a metal mold box 5 , a filling molding box 6th , a press head 7th , a printing plate 8th , a table 9 , Greensand mold forming sensors 10A , 10B , 10C , 10D , a wiring 11 and a mold quality evaluation device 12th . 2 represents a view of the green sand mold formation sensors 10A , 10B , 10C , 10D in the printing plate 8th when viewed from line AA in 1 (View along line AA from 1 ).

The plate 2 has an upper shape (or lower shape) pattern on an upper surface thereof 3 attached for forming a shape of a casting in a green sand mold. The plate is made of aluminum, for example. The carrier 4th is box-shaped and the plate 2 is placed inside the molding box. In addition, green sand is used to form a green sand shape into one of the plate 2 , the metal mold box 5 , the filling molding box 6th and the printing plate 8th surrounding mold forming space. The pressure plate 8th is rectangular and is a component that forms part of a boundary of the molding space defined by the pressure plate 8th and the metal mold box 5 during green sand mold molding by the mold molding apparatus 1 is defined.

For loading green sand through the mold forming device 1 For example, a gravity fall method using the weight of the greensand or a blowing method using air flow is used. The gravity fall method is a method of loading green sand into the mold cavity in which in a Lamellar hopper (not shown) attached to an upper portion of the mold forming apparatus 1 is arranged, accumulated greensand is caused to fall by gravity. Further, the blowing method is a method of loading green sand by blowing green sand inside a sand tank (not shown) into the mold cavity.

Here follows a brief description of a procedure for loading green sand into the mold cavity and compressing it. First is the metal mold box 5 on top of the carrier 4th placed and then the filling molding box 6th on top of the metal mold box 5 overlaid to define the mold space. Next, green sand is loaded into the mold cavity and the pressure plate 8th compresses (presses) the green sand. Due to this, the green sand is packed in the mold forming space and a green sand mold is molded.

(Greensand Mold Forming Sensor)

The green sand mold forming sensors 10A , 10B , 10C , 10D measure a pressure value (peak pressure) applied to a pressure surface between the pressure plate during the molding of a green sand mold 8th and applying green sand within the mold cavity. The green sand mold forming sensors 10A , 10B , 10C , 10D are pressure sensors. In the present embodiment, the green sand shape shape sensors 10A , 10B , 10C , 10D in the four corners of the pressure plate 8th embedded. The reason, which will be described later, that the green sand shape formation sensors 10A , 10B , 10C , 10D embedded in such a manner is a result of taking into account the variation in pressure exerted on the pressing surface of the printing plate 8th is applied. By embedding the green sand mold shape sensors 10A , 10B , 10C , 10D in the four corners of the pressure plate 8th it is possible to see the strength distribution of the entire mold.

In addition, the green sand shape sensors 10A , 10B , 10C , 10D a pressure receiving surface for measuring the pressure exerted in the pressing surface of the pressure plate 8th is exposed, and measures the pressure value (peak pressure) that is applied to the pressing surface between the pressure plate 8th and the green sand mold is applied. At this time, it is desirable that the pressure receiving surface of the green sand mold formation sensors 10A , 10B , 10C , 10D and the pressing surface of the printing plate 8th are in a flush state with no differences in level in between. Because of this, it is possible to measure the precise pressure. In one example, the are green sand mold shape sensors 10A , 10B , 10C , 10D Fluid pressure sensors. An earth pressure sensor can also be called the greensand shape sensors 10A , 10B , 10C , 10D be used.

Next, regarding the green sand mold formation sensors 10A , 10B , 10C , 10D a small pressure receiving surface makes it easier to match the positions where the mold strength of a green sand mold is measured, pointing to positions where the pressure is measured taking into account the size of the pressure plate 8th in which the sensors are embedded and the shape of the pattern 3 , and moreover, as described later, the mold strength of a molded green sand shape by a mold strength gauge at a position in the plate 2 is measured leading to a position in the pressure plate 8th knows where the greensand mold shape sensors 10A , 10B , 10C , 10D measure a pressure, and that a relationship between the pressure value (peak pressure) and the mold strength is established. Meanwhile, since the measurement accuracy is required also in terms of the size of the pressure receiving surface, a diameter of about 5 to 30 mm is desirable.

3 and 4th are lateral cross-sectional views showing the details of a portion of the printing plate 8th represent the green sand shape forming sensors embedded therein 10A , 10B , 10C , 10D having. 3 represents a case where the green sand shape formation sensors 10A , 10B , 10C , 10D are of a screw-in type. As in 3 Shown is a male thread in a of the greensand shape sensors 10A , 10B , 10C , 10D formed, is a female thread in b of the pressure plate 8th and are the green sand shape shaping sensors 10A , 10B , 10C , 10D on the pressure plate 8th screwed on.

Meanwhile represented 4th a case where the green sand mold shape sensors 10A , 10B , 10C , 10D are of a disc shape. As in 4th shown are the greensand mold formation sensors 10A , 10B , 10C , 10D in a hole in the pressure plate 8th placed and an annular socket 13th surrounds the outer edge of the green sand shape sensors 10A , 10B , 10C , 10D . In addition, bolts fix in place 14th the socket 13th and hold the greensand mold formation sensors 10A , 10B , 10C , 10D back.

So it is for them Greensand mold forming sensors 10A , 10B , 10C , 10D also possible to use an object having a specification of either a screw type or a disk shape, and selection can be made in consideration of an embedded space and attachability of the green sand shape forming sensors.

The wiring 11 connects the mold quality evaluation device 12th with the green sand mold forming sensors 10A , 10B , 10C , 10D . In the present embodiment, the green sand shape shape sensors 10A , 10B , 10C , 10D and the mold quality evaluation device 12th by wire (wire communication) over the wiring 11 connected, but can also be connected wirelessly (wireless communication). It is possible, for example, by means of an amplifier, for example, to measure the pressure value (pressure value data) that are transmitted by the green sand shape sensors 10A , 10B , 10C , 10D be detected, amplify and use wireless communication such as wireless LAN or Bluetooth, etc. to be sent from a transmitter to the mold quality evaluation device 12th to send.

(Mold quality evaluation device)

The mold quality evaluation device 12th evaluates the quality of one by the mold forming apparatus 1 formed green sand shape from the pressure value (pressure value data) obtained by the green sand shape forming sensors 10A , 10B , 10C , 10D is measured. 5 Fig. 13 is a block diagram showing a functional configuration of a mold quality evaluation device 12th for wired communication data. The mold quality evaluation device 12th comprises a receiving unit 15th , an amplification unit 16 , an input unit 17th , a mold strength calculation unit 18th , a mold quality determining unit 19th , a display unit 20th , a transmitter unit 21 and a recording unit 22nd .

The receiving unit 15th receives the pressure value (pressure value data) obtained by the green sand shape forming sensors 10A , 10B , 10C , 10D be measured. In this example, wired data is generated from the wiring 11 receive.

The reinforcement unit 16 amplifies the signal amount of the received pressure value (pressure value data). The reinforcement unit 16 is for example an amplifier.

The input unit 17th inputs: the mold strength of a green sand molded shape, which is measured by a mold strength gauge; Values of a slope “a” and an intersection point “b” in an expression y = ax + b described later; and a threshold value of the mold strength of a green sand mold to be molded. It should be noted that the inputting is carried out by a worker. The input unit 17th is for example a keyboard or a touch panel. In the expression y = ax + b, “y” is the mold strength and “x” is that by the green sand mold forming sensors 10A , 10B , 10C , 10D measured pressure value. The expression is a relational expression for determining the mold strength “y” from the slope “a” and the intersection point “b” that were entered and a measured value “x”.

From the slope “a” and the intersection point “b” that are entered in the input unit 17th and from that by the greensand shape shaping sensors 10A , 10B , 10C , 10D measured pressure value (peak pressure), calculated by the mold strength calculation unit 18th the mold strength for each pressure value (peak pressure) measured by the green sand mold shape sensors 10A , 10B , 10C , 10D using the relational expression between the measured value and the mold strength. A method for calculating the mold strength will be described in detail later. The pressure plate 8th is for example a computer or a PLC.

The mold quality determination unit 19th determines the quality of a formed green sand shape from the threshold value in the input unit 17th the entered mold strength and the calculated mold strength. A method of determining the mold quality will be described in detail later. The mold quality determination unit 19th is for example a computer or a PLC.

The display unit 20th indicates: the one by the green sand mold forming sensors 10A , 10B , 10C , 10D measured pressure value (peak pressure); Values of the slope “a” and the intersection point “b” in the relational expression y = ax + b between that by a worker using the input unit 17th entered mold strength and pressure value (peak pressure); the threshold value of the mold strength of a green sand mold to be formed, which has been input by a worker; a mold strength calculation result; and a mold quality determination result, etc. The display unit 20th is for example a liquid crystal display etc.

The transmitter unit 21 sends fault determination data to a Patlite® 23, etc. Sending can be either wired data or wireless data. In addition, a worker who has recognized a defect occurrence in a green sand mold should make an x mark on the relevant green sand mold by confirming that the Patlite® 23 is flashing, etc., thereby making it possible to understand at a glance that this is a green sand mold is defective product. A green sand mold that has been recognized as a defective product does not go through the following steps (metal melt casting) and after skipping these steps it is finally shaken out of the mold.

The recording unit 22nd records pressure value data, mold strength data associated with the pressure values, mold strength calculation results and mold quality determination results, etc. It also keeps this data for each pattern that is attached to the plate 2 is appropriate, recorded. The recording unit 22nd is, for example, a recording medium such as a semiconductor memory or a magnetic disk, etc. In addition, the recording unit 22nd recorded data can be extracted using a USB memory or an SD card, etc.

As described earlier, the green sand shape shape sensors 10A , 10B , 10C , 10D and the mold quality evaluation device 12th be connected wirelessly (wireless communication). 6th Fig. 13 is a block diagram representing a functional configuration in the case where the pressure value (pressure value data) obtained by the green sand shape forming sensors 10A , 10B , 10C , 10D is measured wirelessly with the mold quality evaluation device 12th connected (wireless communication). The pressure value (pressure value data) obtained by the green sand mold formation sensors 10A , 10B , 10C , 10D is measured is by an amplification unit 16 ' near the green sand shape sensors amplified and wireless from a pressure value transmitter unit 24 to a receiving unit 15 ' the mold quality evaluation device 12th Posted. The mold quality evaluation device 12th for wireless data, shown in 6th , comprises a receiving unit 15 ' the input unit 17th , the mold strength calculation unit 18th , the mold quality determining unit 19th , the display unit 20th , the transmitter unit 21 and the recording unit 22nd .

After that by the greensand mold forming sensors 10A , 10B , 10C , 10D measured pressure value (pressure value data) by the amplification unit 16 ' has been amplified, the receiving unit receives 15 ' from the pressure value sending unit 24 wireless data sent. It should be noted that the functions of the input unit 17th , the mold strength calculation unit 18th , the mold quality determining unit 19th , the display unit 20th , the transmitter unit 21 and the receiving unit 22nd the same as the functions of the mold quality evaluation device 12th for wired data are described earlier.

(Relationship between pressure measured by green sand mold forming sensors and mold strength of molded green sand mold)

1. 1. Grünsandform-Formungssensoren wurden in einer Druckplatte installiert (eingebettet). Wie in 7 gezeigt, waren die Installationsorte an insgesamt drei Stellen gesetzt: in einem zentralen Abschnitt (S3) und in zwei Eckenorten (S1, S2), die den Zentralabschnitt der Druckplatte einrahmen. Weiter wurde das vorliegende Experiment mit einem angebrachten Muster und ohne angebrachtes Muster durchgeführt.
2. 2. Ein Grünsandform wurde durch eine Formungsmaschine mit in der Druckplatte installierten Grünsandform-Formungssensoren geformt. Zusätzlich wurde während eines Pressschritts der auf die Druckoberfläche der Druckplatte aufgebrachte Druck durch die Grünsandform-Formungssensoren an den drei Stellen gemessen. Zeitliche Änderungen beim Druckwert wurden gemessen und aufgezeichnet. In Bezug auf das Pressen wurde Druck graduell bis zum eingestellten Druck aufgebracht und wurde aufgehoben, wenn der eingestellte Druck erreicht wurde.
3. 3. Die Gussformfestigkeit einer Grünsandform an einer Teilungsebene, die zu den Positionen weist, wo der Druck durch die Grünsandform-Formungssensoren gemessen wurde, wurde durch eine Gussformfestigkeitslehre gemessen und die Beziehung zwischen dem Druckwert und der Gussformfestigkeit wurde untersucht. Es ist anzumerken, dass mit dem angebrachten Muster die Gussformfestigkeit an der Teilungsebene, die zu der Position weist, wo der Druck durch den Grünsandform-Formungssensor im Zentralabschnitt (S3) gemessen wurde, die Gussformfestigkeit an der oberen Oberfläche des Musters ist. Weiter wurde in Bezug auf die Festigkeitslehre, die die Gussformfestigkeit maß, eine Invasivtyp-Gussformfestigkeitslehre breit in Gussformfabriken verwendet wird, um die Formbarkeit von Grünsandformen zu evaluieren, und welche die Gussformfestigkeit durch Einführen von ungefähr 10 mm in die Gussform einer Nadel mit einem Spitzendurchmesser von ungefähr 3 mm misst, verwendet.

Next, a description will be given of the relationship between the mold strength of a molded green sand mold and the pressure value (peak pressure) applied to the pressing surface of the pressure plate and measured by the green sand mold molding sensors. In order to examine the relationship between the above, an experiment was carried out using a molding machine. 7th Fig. 13 is a schematic view representing a configuration of an experiment carried out here, wherein (a) is a cross-sectional view, and (b) is a plan view of a pressure plate. Although the pattern 3 in the in 7 (a) cross-sectional view shown, the experiment was performed with the pattern attached 3 and with no pattern attached 3 executed. Next shows the top view of the pressure plate 8th in 7 (b) : a positional relationship between the pressure plate and the sensors; an integrated amplifier recorder 25th that records signals from pressure sensors and a computer 26th , the one with the integrated amplifier recorder 25th is connected and performs an analysis, such as the graphical recording of sensor readings. The experiment was carried out as follows.

1. 1. Greensand mold forming sensors were installed (embedded) in a pressure plate. As in 7th shown, the installation locations were set in a total of three places: in a central section (S3) and in two corner locations (S1, S2), which frame the central section of the pressure plate. Further, the present experiment was carried out with a pattern attached and no pattern attached.
2. 2. A green sand mold was molded by a molding machine with green sand mold molding sensors installed in the pressure plate. In addition, during a pressing step, the pressure applied to the printing surface of the printing plate was measured by the green sand mold shape sensors at the three locations. Changes in the pressure value with time were measured and recorded. With respect to pressing, pressure was gradually applied up to the set pressure and was released when the set pressure was reached.
3. 3. The mold strength of a green sand mold at a parting plane facing the positions where the pressure was measured by the green sand mold sensors was measured by a mold strength gauge, and the relationship between the pressure value and the mold strength was examined. Note that with the pattern attached, the mold strength at the parting plane facing the position where the pressure was measured by the green sand mold sensor in the central portion (S3) is the mold strength at the top surface of the pattern. Further, with respect to the strength gauge that measured the mold strength, an invasive-type mold strength gauge has become is widely used in mold factories to evaluate moldability of green sand molds, and which measures mold strength by inserting about 10 mm into the mold of a needle with a tip diameter of about 3 mm.

In addition, the above-mentioned 2 and 3 were carried out on a plurality of green sand molds and the data was collected.

(Experimental results)

8th Fig. 13 is a graph representing an example representing changes with time in pressure of a green sand mold shape sensor in the pressing step. Note that this drawing represents the case without the pattern, while the pressing pressure was set at 0.6 MPa and measurements were made with sensors at three locations. As in 8th As shown, in this molding machine, the peak pressure in the pressing step was reached about 3 seconds after the pressing started.

Further, when the relationship between the position of the shape sensor and the tip pressure is confirmed, the pressure at the central portion S3 of the printing plate is low and the pressure at the printing plate periphery (S1, S2) becomes higher. At this point, it was possible to confirm that, since the printing plate periphery is close to the metal flask wall, the green sand is compacted by the frictional resistance between the green sand and the metal flask; on the contrary, since the central portion S3 is removed from the metal flask wall and there is no compression due to the influence of the metal flask, the pressure becomes lower compared to the periphery. Note that, when the pattern is present, it was found that the peak pressure of the pressure sensor at the central portion S3 is larger than that at the corners due to the level of compacting green sand on the pattern, the pressing force in it becomes higher Section is used up and the pressing force at the periphery decreases, so that the peak pressure of the shaping sensor at the periphery S1, S2 becomes lower.

9 Fig. 13 is a graph which, after the above-mentioned experiment is repeated, summarizes the relationship between the mold strength and the peak pressure of the green sand mold forming sensors, which varies with the set pressing pressure and the state of charge of the green sand, with measurements of the peak pressure on the pressing surface of the Pressure plate and the mold strength of green sand molds at a division plane pointing to positions where the pressure was measured, respectively applied for the presence or absence of the pattern, in the central portion (S3) or the periphery (S1, S2). With regard to the in 9 As shown in the relationship between the peak pressure of the green sand mold sensors and the mold strength of the green sand molds at the parting plane facing the position where the pressure was measured, it is found that the points corresponding to the periphery (S1, S2) have a high correlation with very little influence of the presence or absence of the pattern. Meanwhile, the relationship for the points corresponding to the central portion S3 changed depending on the presence or absence of the pattern, and showed a tendency of high mold strength relative to the peak pressure in the presence of the pattern as compared with the absence thereof.

Summarizing these results, the pressure reaching the pressing surface of the printing plate differs depending on whether the position is the periphery or the central portion and the presence or absence of the pattern. It became clear that the mold strength at the position facing the printing plate is positively correlated with the pressure reaching the printing surface of the printing plate, but unlike the central portion where the relationship differs depending on the presence or absence of the pattern, the periphery is not through affects the presence or absence of the pattern.

Regarding the relationship between the mold strength and the loading density of green sand, the mold strength is high at a high loading density. Load density and mold strength have a strong, positive correlated relationship with compaction force. The peak pressure measured by the shaping sensors is synonymous with the compaction force, so that a high peak pressure will lead to a high load density. When the loading density of a green sand molded mold is low, that is, the mold strength is low, there is a fear of defects such as molten metal infiltration, sand droplet / sand inclusion, molten metal leakage, etc. Further, when the loading density of a green sand molded mold is too high , sliding resistance between the pattern and the mold increases, and there is a fear of mold removal defects. As such, maintaining the detected peak pressure of the green sand mold formation sensors at an appropriate level results in a reduction in defects.

(Arrangement position of green sand mold forming sensor)

The pressure applied to the green sand mold forming sensors embedded in the pressure plate changes due to the causes mentioned above and therefore, the embedding positions of the green sand shape forming sensors must be places where it is possible to ensure these circumstances. Accordingly, if a plurality of green sand shape sensors are installed, it is possible to detect defects under more conditions. However, due to space constraints and from an economic perspective, this is not realistic and it is desirable to be able to detect and evaluate pressure using a smaller number of sensors.

As mentioned earlier, this is used to load greensand through the mold forming apparatus 1 a gravity fall method or a blowing method using an air stream is employed. In the gravity case method using a slat hopper, etc. as mentioned earlier, a bias when the green sand is loaded into the slat hopper may become a bias when loading into the mold cavity. Furthermore, a bias can occur in the blow molding process when loading into the mold-forming space, due to circumstances such as the distance from the injection nozzle, sand blockage in the nozzle opening, etc. With the subsequent compression of the green sand, these biases appear as biases in the compression pressure caused by the printing plate 8th caused on the greensand. It is necessary to arrange the green sand mold formation sensors in consideration of the occurrence of such biases in the initial charge amounts.

In addition, in cases where a difference in the measurement value of an arranged green sand shape forming sensor is outside a predetermined threshold range, it can be determined that the bias of the initial loading is large and it is possible to take measures such as: improving the condition in which Greensand is loaded into the lamellar hopper; Adjustment of injection air pressure or injection time; or improving the condition (blockage, abrasion, etc.) of the injection nozzle. Further, the fluidity of the green sand has an influence when the green sand is loaded into the lamellar hopper, when loaded from the lamellar hopper to the die-forming space, or when blown, etc. This flowability of the green sand varies according to the sand properties such as the water content of the green sand, and it is therefore possible to mold the sand using a sand processing device such as a fulling machine that of the mold forming device 1 to be fed green sand kneads to adjust.

Further, when green sand is compacted, the green sand is compressed by a compressing force, and pressure is detected by the green sand mold shape sensors embedded in the pressure plate. As shown in the above-mentioned experimental results, it was confirmed that the relationship between the pressure detected by the green sand mold forming sensors embedded in the pressure plate and the mold strength at the position facing the pressure plate differs depending on the presence or absence of a pattern in the central portion, but is unaffected by the presence or absence of a pattern in the periphery.

Thus, in order to evaluate the mold strength by the magnitude of the compression force of the pressure plate, the green sand mold shape sensors are preferably provided near the sides of the mold box that are unaffected by the presence or absence of a pattern, particularly the corner portions. If a measurement value from a green sand mold sensor placed in this position does not reach a predetermined lower limit threshold value, it can be judged that sufficient mold strength has not been obtained, and measures to increase the compression force can be taken. If the measured value is higher than an upper limit threshold value, it can be decided that the mold strength is more than sufficient and measures for lowering the compression force can be taken.

In the present embodiment, in consideration of the step of loading the green sand and the step of compacting the green sand, the green sand shape formation sensors become 10A , 10B , 10C , 10D in the four corners of the pressure plate 8th embedded.

It should be noted that the relationship between the peak value of the pressure of the green sand mold forming sensors and the mold strength is also the same when another type of flask molding machine or a flaskless molding machine is used. As such, this relationship can also be applied in a die-forming apparatus of a second embodiment which will be described later.

(Method of Calculating Mold Strength)

Next, a description will be given of a method of calculating mold strength using the mold strength calculating unit 18th . As mentioned above, it has been ensured that there is a correlative relationship between the mold strength and the peak pressure of the green sand mold shape sensors. The mold strength calculation unit 18th uses this relationship to calculate the mold strength from the on the input unit 17th entered mold strength and the Greensand mold forming sensors 10A , 10B , 10C , 10D measured pressure value (peak pressure).

Specifically, includes the calculation of the mold strength by the mold strength calculating unit 18th two steps.

Step 1

A predetermined number of green sand molds are molded in advance, and a pressure value (peak pressure) during pressing is obtained by the green sand mold molding sensors 10A , 10B , 10C , 10D measured. Further, for each of the molded green sand molds, the mold strength at the parting plane facing the positions where the pressure by the green sand mold molding sensors is determined 10A , 10B , 10C , 10D was measured, measured and inserted into the input unit by a worker 17th entered. In addition, a worker determines the expression y = ax + b from the relationship between the mold strength and the pressure value (peak pressure).

Note that, in the present embodiment, based on the above-mentioned experimental results, the green sand shape formation sensors 10A , 10B , 10C , 10D in the four corners of the pressure plate 8th are embedded. By measuring the pressure applied to the printing surface of the printing plate at the four locations and determining a relationship with the mold strength, it is possible to determine the mold quality using a small number of green sand mold shape sensors while taking into account variation in the pressure of the printing surface of the printing plate. Further, when a predetermined number of molds are made, by changing the pressing pressure, it is possible to determine a relationship between the pressure applied to the pressing surface and the mold strength over a wider range.

10 shows an example of one on the display unit 20th displayed screen. In the present example, a predetermined green sand shape is first formed, and are determined by the green sand shape forming sensors 10A , 10B , 10C , 10D seven pressure values (peak pressures) measured at this time are displayed on the screen. It should be noted that it is also possible to switch to a screen showing the information provided by the green sand shape formation sensors 10A , 10B , 10C , 10D measured seven pressure values (peak pressures) and that furthermore a screen can be configured so that by the green sand mold formation sensors 10A , 10B , 10C , 10D seven measured pressure values (peak pressures) are displayed on the screen.

In addition, for each of the molded green sand molds, the mold strength at the parting plane facing the positions where the green sand mold molding sensors are used 10A , 10B , 10C , 10D were arranged as an input value entered by a worker. Here are “Peak Pressure A” and “Mold Strength A” that are shown in 10 are shown, the peak pressure value of the green sand shape formation sensor, respectively 10A and the mold strength at the position of the green sand mold shape sensor 10A . Next, “Peak Pressure B” and “Mold Strength B” are in 10 each is the peak pressure value of the green sand mold formation sensor 10B and the mold strength at the position of the green sand mold shape sensor 10B ; “Peak Pressure C” and “Mold Strength C” displayed on the switched screen are each the peak pressure value of the green sand mold forming sensor 10C and the mold strength at the position of the green sand mold shape sensor 10C ; and “Peak Pressure D” and “Mold Strength D” displayed on the switched screen are the peak pressure value of the green sand mold forming sensor, respectively 10D and the mold strength in the position of the green sand mold shape sensor 10D .

The mold strength calculation unit 18th plots the mold strength and the peak value of the pressure of the green sand mold shape sensors on one graph (in the present example 7 × 4 = 28 spaces). In addition, when a worker inputs predetermined values for the slope “a” and the intersection “b” of the expression, a straight line y = ax + b is displayed. While confirming the plots, a worker changes numerical values of the slope "a" and the intersection "b", as needed and determining that there is a linear correlation between the plots, determines an end expression y = ax + b. It should be noted that if there is no problem with the mold strength in a green sand mold for which the mold strength has been measured by a worker, it is possible to continue manufacturing as given by performing the following steps (core setting step, metal melting step). Casting step etc.). Note that in the above description, a worker inputted the slope “a” and the intersection “b” of the expression, but they can also be entered using a computer or PLC and performing linear regression by a least squares method, etc. to be determined.

step 2

After determining the expression y = ax + b, the molding of the green sand shape begins. After starting, the expression y = ax + b is used to denote the mold strength at the positions of the green sand mold shape sensors 10A , 10B , 10C , 10D from the pressure value (peak pressure), which is calculated by the green sand mold formation sensors 10A , 10B , 10C , 10D was measured. Because of this, there is no need for a worker to separately measure the mold strength.

Note that, in the present example, the mold strength is measured using a mold strength gauge, and the number of tip pressures and mold strengths displayed on the screen are seven for both A and B. However, it may be appropriate based on the specifications of the mold forming apparatus 1 , Specifications such as the shape and size of the green sand mold to be molded, etc. or the specifications of the green sand are changed.

(Method for determining mold quality)

Next, a description will be given of a method of determining mold quality using the mold quality determining unit 19th . The mold quality determination unit 19th determines the quality of a green sand mold from the threshold value of the mold strength that is entered in the input unit 17th is input, and that by the mold strength calculating unit 18th calculated mold strength. Specifically, it includes determining the mold quality by the mold quality determining unit 19th two steps.

Step 1

First, a worker inputs a threshold value of the mold strength of a green sand mold to be molded. 11 Fig. 10 shows an example of a screen that appears on the display unit 20th is shown. In this example, specific threshold values entered by a worker are displayed. Here "Sensor A gives normal strength ranges" in 11 the lower limit value and the upper limit value of the mold strength at the position of the green sand mold forming sensor 10A at; indicates the "Sensor B normal strength range" in 11 the lower limit value and the upper limit value of the mold strength at the position of the green sand mold forming sensor 10B at; gives "Sensor C normal strength range" in 11 the lower limit value and the upper limit value of the mold strength at the position of the green sand mold forming sensor 10C at; and gives "Sensor D normal strength range" in 11 the lower limit value and the upper limit value of the mold strength at the position of the green sand mold forming sensor 10D at. Further, there is "Mold Strength Difference (Max - Min) Abnormality Value" shown in 11 , a threshold value at which the difference between the maximum and minimum values of the mold strength obtained from the pressure value of the green sand mold forming sensors 10A , 10B , 10C , 10D is determined as an abnormality value is set. In the present example, the lower limit of the mold strength is set at the position of the green sand mold shape sensors 10A , 10B , 10C , 10D is set as 10.0 (N / cm ² ), the upper limit value thereof is set as 20.0 (N / cm ² ) and becomes the threshold value at which the difference between the maximum value and the minimum value of the mold strength at the position of the green sand mold Forming sensors 10A , 10B , 10C , 10D is set as an abnormality value is set as 5.0 (N / cm ² ).

step 2

After the expression y = ax + b by the mold strength calculator 18th is determined and the mold strength threshold is entered, molding of the green sand mold begins. After starting, the strength will be at the position of the green sand mold shape sensors 10A , 10B , 10C , 10D automatically from the by the green sand mold forming sensors 10A , 10B , 10C , 10D measured pressure value (peak pressure) is calculated. In addition, the quality of the green sand mold is determined from the entered threshold value for the mold strength and the calculated mold strength. Here, the determination of the quality of a green sand mold is carried out as follows.

In the present example, the threshold values of the mold strength A, the mold strength B, the mold strength C, and the mold strength D are all set as 10.0 (N / cm ² ) or greater and 20.0 (N / cm ² ) or less and becomes the Abnormality threshold value of the difference between the maximum value and the minimum value of the mold strength at the positions of the green sand mold forming sensors 10A , 10B , 10C , 10D set as 5.0 (N / cm ² ) or larger. Similarly, in the case where the mold strength at the position of the green sand mold shape sensor 10A 13.0 (N / cm ² ) is the mold strength at the position of the green sand mold shape sensor 10B 12.0 (N / cm ² ) is the mold strength at the position of the green sand mold forming sensor 10C Is 16.0 (N / cm ² ), and the mold strength at the position of the green sand mold shape sensor 10D 14.0 (N / cm ² ), the mold strength A, the mold strength B, the mold strength C, and the mold strength D are all within the threshold values. Furthermore, the maximum value of the mold strengths A, B, C, D is 16.0 (N / cm ² ), the minimum value is 12.0 (N / cm ² ) and the difference between the maximum and the minimum is 4.0 (N / cm ² ) which is within the range and therefore determines the mold quality determining unit 19th that the mold quality is okay.

In contrast, in the case where the mold strength is at the position of the green sand mold shape sensor 10A Is 11.0 (N / cm ² ), the mold strength at the position of the green sand mold shape sensor 10B 17.0 (N / cm ² ) is the mold strength at the position of the green sand mold forming sensor 10C Is 12.0 (N / cm ² ) and the mold strength at the position of the green sand mold shape sensor 10D 16.0 (N / cm ² ), the mold strength A, the mold strength B, the mold strength C, and the mold strength D are all within the threshold values. However, the maximum value of the mold strengths A, B, C, D is 17.0 (N / cm ² ), the minimum value is 11.0 (N / cm ² ), and the difference between the maximum and the minimum is 6.0 ( N / cm ² ) which is not within the range, and therefore the mold quality determining unit determines 19th that the mold quality is defective.

12th shows an example of one on the display unit 20th displayed screen. Here "peak pressure A", "peak pressure B", "peak pressure C" and "peak pressure D" enter 12th each represents the peak pressure value of the green sand shape forming sensor 10A , the peak pressure value of the green sand mold formation sensor 10B , the peak pressure value of the green sand mold formation sensor 10C and the peak pressure value of the green sand mold formation sensor 10D at. Further, “mold strength A”, “mold strength B”, “mold strength C” and “mold strength D” each give the mold strength at the position of the green sand mold forming sensor 10A which is determined by the mold strength calculation unit 18th is calculated, the mold strength at the position of the green sand mold forming sensor 10B which is determined by the mold strength calculation unit 18th is calculated, the mold strength at the position of the green sand mold forming sensor 10C which is determined by the mold strength calculation unit 18th is calculated, and the mold strength at the position of the green sand mold shape sensor 10D obtained by the mold strength calculation unit 18th is calculated.

Furthermore, there is "Difference in mold strength (max. - min.)" In 12th the difference between the maximum value and the minimum value of the mold strengths A, B, C, D. Next gives "determination" in 12th a mold quality determination result by the mold quality determination unit 19th at.

It should be noted that on the screen of the display unit 20th in 12th a weak numerical value is indicated by shading or coloring the inside of a cell, and OK (normal) and FT (faulty) can be understood at a glance.

Note that the threshold values and the difference between the maximum value and the minimum value set for the mold strength A, the mold strength B, the mold strength C, and the mold strength D are appropriately set according to the specifications of the mold forming apparatus 1 , Specification such as shape, size, etc. of the green sand mold to be molded, the location of the green sand mold or the specifications of the green sand etc. can be determined. In addition, these values are associated with a pattern number.

In the mold forming machine 1 In the present embodiment, even if the specification such as shape, size, etc. of a green sand mold to be molded changes, it is possible in any case that the mold strength calculating unit 18th the mold strength is calculated and that the mold quality determining unit 19th the quality of the formed green sand mold is determined from the calculated mold strength.

Further, in this embodiment, calculated mold strength values are used in making OK (normal) and FT (faulty) determinations, for example, but the determination is not limited thereby. Since a positive correlative relationship between the mold strength and the pressure value of the green sand mold forming sensors has been confirmed, the pressure values of the green sand mold forming sensors can be used as a direct reference in determining the mold quality without calculating the mold strength from the pressure value of the green sand mold forming sensor.

For example, use the values in the table of thresholds in 1 , which serve as the determination reference for the mold quality, all a pressure value of the green sand mold forming sensor as a predetermined threshold value and measured pressure values of the green sand mold forming sensors can be determined as OK (normal) or FT (faulty) in view of this table.

(Method of Calculating Mold Quality Using Mold Molding Apparatus)

Next, a description will be given of a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus 1 . 13th Fig. 13 shows steps in a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus 1 according to the first embodiment. It should be noted that in 13th a lamellar hopper 27 with the print head 7th of the in 1 mold forming apparatus shown 1 is coupled. The lamellar hopper 27 has a structure in which a predetermined amount of greensand is charged from a greensand transport device (not shown) and, after being briefly retained, lamellae open 28 at a lower area of the lamellar hopper 27 and the green sand is loaded in the mold forming space.

1. 1. Wenn Formen begonnen wird, hebt sich der Tisch 9, und dadurch wird ein in 13(a) gezeigter Zustand erzielt. In dieser Zeit wird eine vorbestimmte Menge an Grünsand in den Lamellenschütttrichter 27 aus der Grünsand-Transportvorrichtung (nicht gezeigt) geladen.
2. 2. Dann, wie in 13(b) gezeigt, öffnen sich die Lamellen 28 am unteren Bereich des Lamellenschütttrichters 27 und der Grünsand innerhalb des Lamellenschütttrichters 27 wird in den durch die Platte 2, den Metallformkasten 5 und den Befüllungsformkasten 6 definierten Raum geladen.
3. 3. Dann, wie in 13(c) gezeigt, bewegen sich der gekoppelte Druckkopf 7 und der Lamellenschütttrichter 27, wird die Druckplatte 8 direkt über dem Gussform-Formungsraum angeordnet und Als Nächstes hebt sich der Tisch 9 und dadurch wird der Grünsand innerhalb des Gussform-Formungsraums gedrückt (komprimiert). Zu dieser Zeit messen die Grünsandform-Formungssensoren 10A, 10B, 10C, 10D den Druckwert (Spitzendruck) auf der Druckoberfläche der Druckplatte. Es ist anzumerken, dass die Gussform im vorliegenden Schritt geformt wird. Zu dieser Zeit sind die Grünsandform-Formungssensoren 10A, 10B, 10C, 10D zwischen der Wand des Metallformkastens 5 der Druckplatte 8 und dem Muster 3.
4. 4. Der Druckwert (Spitzendruck) an der Druckoberfläche der Druckplatte wird auf die Gussformqualitäts-Evaluierungsvorrichtung 12 übertragen und die Qualität der Grünsandform, die gerade geformt worden ist, wird evaluiert.

The molding of the green sand mold by the mold forming device 1 follow the procedure below.

1. 1. When molding is started, the table rises 9 , and this creates an in 13 (a) shown condition achieved. During this time, a predetermined amount of green sand is poured into the lamellar hopper 27 loaded from the greensand transport device (not shown).
2. 2. Then, as in 13 (b) shown, the slats open 28 at the bottom of the lamellar hopper 27 and the green sand inside the lamellar hopper 27 is in the through the plate 2 , the metal mold box 5 and the filling molding box 6th defined space.
3. 3. Then, as in 13 (c) shown, the coupled printhead move 7th and the lamellar hopper 27 , becomes the printing plate 8th placed directly above the mold forming space and next the table rises 9 and thereby the green sand is pressed (compressed) within the mold forming space. At this time, the green sand shape formation sensors measure 10A , 10B , 10C , 10D the pressure value (peak pressure) on the printing surface of the printing plate. It should be noted that the mold is molded in the present step. At this time, the green sand mold shape sensors 10A , 10B , 10C , 10D between the wall of the metal molding box 5 the printing plate 8th and the pattern 3 .
4. 4. The pressure value (peak pressure) on the printing surface of the printing plate is applied to the mold quality evaluation device 12th and the quality of the green sand mold that has just been molded is evaluated.

The quality evaluation by the mold quality evaluation device 12th is performed after the expression y = ax + b, which represents the relationship between the mold strength and the peak value of the pressure of the green sand mold shape sensors, is determined in advance. In addition, a flows through the mold quality evaluation device 12th Green sand mold determined as OK as it is along the route and subsequent steps (metal melt casting, etc.) are carried out. Meanwhile, a flows through the mold quality evaluating device 12th Green sand shape determined to be defective as it is along the route, but the subsequent steps (metal fusing, etc.) are not carried out. The green sand mold skips these steps and is shaken out of the mold as a casting mold to be discarded in the same way as a green sand mold which has a casting mold quality evaluation determined as OK. It is thus possible to make a determination of “good” or “bad” in relation to the quality of the molded casting mold for each molding box, which can therefore lead to a casting mold quality assurance for each molding box. Further, it is possible to evaluate a defect at the time of molding a green sand mold, and therefore it is possible to reduce defects in the produced moldings. Furthermore, it is possible to omit unnecessary labor and therefore it is possible to reduce the production cost.

5. Then descends in the mold forming device 1 the table 9 , the filling molding box separates 6th from the top surface of the metal mold box 5 , and when the table lowers further, the metal mold box containing the green sand mold becomes 5 Placed on a roller conveyor associated with subsequent steps such as core setting, metal melt casting, etc., the pattern becomes 3 removed from the greensand mold and stops lowering the table 9 . Next is the metal mold box containing the green sand mold 5 conveyed to a subsequent step on the roller conveyor and the metal mold box becomes 5 into the mold forming apparatus 1 loaded in preparation for the next molding. It should be noted that when lowering the table 9 begins to pour a predetermined amount of green sand into the lamellar hopper 27 with closed slats 28 is fed.

6. When the metal mold box 5 has been loaded in preparation for the next mold and the feeding of green sand to the lamellar hopper 27 has been completed, the coupled printhead will move 7th and lamellar hopper 27 the table rises 9 in a state in which the lamellar hopper 27 is located directly above the mold forming space and begins molding the next green sand mold.

In addition, pressure value data, mold strength data associated with pressure values, mold strength calculation results, and mold quality determination results, etc. generated during the molding step are all stored in the recording unit 22nd the mold quality evaluation device 12th recorded. Therefore, it is possible to use these numerical values to determine the operational status of the mold. Forming device 1 to monitor and these numerical values are used in quality control, maintenance and debugging of the mold forming apparatus 1 useful. Furthermore, using these numerical values can lead to early detection of causes of defects, such as: sand spill, casting burn-in, and camber, which occur due to loading defects; and swelling of a green sand mold due to molten metal pressure after casting.

Furthermore, those in the recording unit 22nd recorded data for each on the disk 2 attached patterns recorded. Therefore, it is possible to compare and examine a condition such as a defect in a green sand mold with pressure value data, and setting a more accurate threshold value becomes possible.

Further, in the present embodiment, a worker determines the expression y = ax + b in consideration of the slope “a” and the intersection point “b” of the expression from the mold strengths and peak values of the pressure of the green sand mold forming sensors plotted on a graph. However, it is also possible to configure the mold strength calculation unit 18th automatically calculates the term y = ax + b from the relationship between the mold strength and the peak pressure of the green sand mold sensors using a computer or a PLC and performing linear registration by a least square method, etc.

Further, in the present embodiment, in the case where a molded green sand shape is determined to be a defect, a worker clarifies that the green sand shape in question is a defect. However, it is also possible to configure so that a determination result is automatically communicated to mold equipment of a subsequent step (molten metal casting, etc.). In this case, in the subsequent step, the mold equipment automatically detects that the green sand mold in question is defective, skips the step (skips it) and finally the green sand mold in question is shaken out of the mold.

Further, in the present embodiment, are the green sand shape shape sensors 10A , 10B , 10C , 10D in the four corners of the pressure plate 8th embedded. However, even if the number of in the printing plate 8th embedded greensand shape sensors is small, it is possible to calculate the relationship between the mold strength and the peak pressure of the greensand shape sensors. In this case, the accuracy is a little lower as compared with the case where the green sand shape forming sensors are embedded in four places, but it is possible to cut costs.

In this case, it is also possible to have green sand shape sensors in two places on a line between opposite corners, which in 2 are shown to embed: positions 10A and 10B ; or 10C and 10D . 14th and 15th show other examples of the printing plate 8th with embedded green sand shape forming sensors 10A , 10B . In these drawings, 3a shown by two-dot chain lines represents the corresponding position of the pattern 3 on the plate 2 having the pattern attached thereto in the mold forming space. In 14th are the two green sand mold shape sensors 10A , 10B near the central portion of the long sides of the pressure plate 8th embedded. In 15th are the two green sand mold shape sensors 10A , 10B near the central portion of the short sides of the printing plate 8th embedded.

In either case, the locations where the green sand mold forming sensors are embedded correspond to locations between the metal mold box 5 and the pattern 3 in the mold forming space, that is, between the metal mold box 5 and the pattern 3 on the plate 2 who have favourited the pattern 3 has attached thereto, and on the side of the printing plate or of printing foot indicative portions without the pattern on the plate 2 .

Thus, according to the mold molding apparatus of the first embodiment, the green sand mold molding sensors measure 10A , 10B , 10C , 10D during molding of a green sand mold, a pressure value (peak pressure) applied to a pressure surface between the pressure plate 8th and applying green sand within the mold cavity. Next, calculated from the correlative relationship between the pre-measured mold strength and the peak pressure of the green sand mold forming sensors 10A , 10B , 10C , 10D the mold strength calculation unit 18th the mold quality evaluation device 12th the mold strength from the pressure value (peak pressure) measured by the green sand mold forming sensors 10A , 10B , 10C , 10D for a molded green sand mold. Next, the mold strength calculating unit determines 18th the mold quality evaluation device 12th the quality of a green sand mold from the preset threshold value of the mold strength and that determined by the mold strength calculation unit 18th calculated mold strength. Because of this, it is possible to individually calculate the mold strength of molded green sand molds without measurement using a mold strength gauge, and further evaluate the quality of green sand molds.

Further, according to the mold forming apparatus of the first embodiment, a green sand mold is passed through which is found to be defective by the mold quality evaluation apparatus 12th has been determined, subsequent steps (metal melt casting etc.) not and is shaken out as a casting mold to be discarded. Therefore, it is possible to reduce defects in the green sand shapes produced. Furthermore, it is possible to omit unnecessary labor and therefore it is possible to reduce production costs.

Further, according to the mold forming apparatus of the first embodiment, it is possible to make a determination of “good” or “bad” in terms of the quality of a molded mold for each flask, which can therefore lead to a mold quality assurance position for each flask.

Further, according to the mold forming apparatus of the first embodiment, pressure value data, mold strength data associated with pressure values, mold strength calculation results, and mold quality determination results generated during the molding step are all stored in the recording unit 22nd the mold quality evaluation device 12th recorded. Therefore, it is possible to use these numerical values to determine the operating condition of the mold forming apparatus 1 to monitor and these numerical values can be used in quality control, maintenance and fault detection of the mold-forming device 1 to be useful. Furthermore, using these numerical values can lead to early detection of causes of defects such as: sand spill, casting burn-in, and mold crashes that occur during load defects; and swelling of a green sand mold due to molten metal pressure after casting.

Furthermore, according to the mold molding apparatus of the first embodiment, those in the recording unit 22nd recorded data for each on the disk 2 attached patterns recorded. Therefore, it is possible to compare and examine a condition such as a defect in a green sand mold with pressure value data, and setting a more accurate threshold value becomes possible.

(Second embodiment)

Next, a description will be given of a second embodiment of the mold forming apparatus, the mold quality evaluating apparatus, and the mold quality evaluating method according to the present invention. Note that, in the second embodiments described below, those with the first embodiment for configurations are given the same reference numerals in the drawings and descriptions thereof are omitted. In the second embodiment, a flaskless molding machine is used instead of a flask molding machine.

The second embodiment will be described with reference to the accompanying drawings. 6th FIG. 13 represents a diagram of a structure of the mold forming apparatus according to the second embodiment 17th represents a configuration of a portion of the mold forming apparatus, the portion evaluating the mold quality. The mold molding apparatus according to the present embodiment is a flaskless molding machine in which, after a green sand mold is molded, the green sand mold is taken out from a mold box.

A mold forming device 29 includes the plate 2 with the pattern 3 attached to the upper and lower surfaces thereof, a feeder cart 30th , a coat (Cope, metal mold box) 31, a train (drag, metal mold box) 32 , an upper pressure plate 33 , a lower pressure plate 34 who have favourited Greensand Mold Forming Sensors 10A , 10B , 10C , 10D embedded in a pressing surface of the upper pressure plate 33 , Greensand mold forming sensors 10E , 10F , 10G , 10H embedded in a pressing surface of the lower pressure plate 34 who have favourited wiring 11 and the mold quality evaluation device 12th . It should be noted that 17th Figure 3 is a view of the greensand mold formation sensors 10A , 10B , 10C , 10D embedded in the upper pressure plate 33 when viewed from line BB in 16 represents. It should be noted that the green sand shape shape sensors 10E , 10F , 10G , 10H into the lower pressure plate 34 are embedded and in similar places to those in 17th (the reference numerals for the sensors when the lower pressure plate is shown by line CC in 16 are shown in brackets).

The plate 2 has a pattern on the upper and lower surfaces thereof 3 attached to form a mold of a casting in a green sand mold. The delivery car 30th indicates the plate placed on it 2 and makes round trips between the inside and outside of the mold forming apparatus 29 according to the step. The coat 31 has green sand charged therein to form an upper mold of the green sand mold. In other words, it's through the coat 31 , the upper pressure plate 33 and the plate 2 The surrounding mold-forming space is loaded with green sand. The train 32 has green sand charged therein to form a lower mold of the green sand mold. In other words, the one from the train 32 , the lower pressure plate 34 and the plate 2 The surrounding mold-forming space is loaded with green sand. The upper pressure plate 33 and the lower pressure plate 34 are rectangular and are components that are part of a boundary of the pressure plate and the jacket 31 or the train 32 during green sand molding by the mold molding apparatus 29 Form defined shaping space.

For loading green sand through the mold forming device 29 a blowing method using a stream of air is used. The blowing method is a method of loading green sand by blowing green sand onto the top and bottom surfaces of the plate 2 from green sand injection ports 35 , 35 of the coat 31 and the train 32 .

The upper pressure plate 33 and the lower pressure plate 34 act via a cylinder (not shown) and the upper and lower green sand molds are simultaneously compressed and compressed into the jacket 31 loaded greensand and in the train 32 shaped loaded greensand.

(Greensand Mold Forming Sensor)

The green sand mold forming sensors 10A , 10B , 10C , 10D measure one to the pressure surface between the upper pressure plate while forming a green sand mold 33 and that inside the mantle 31 loaded greensand applied pressure value (peak pressure). The green sand mold forming sensors 10E , 10F , 10G , 10H measure one to the pressure surface between the lower pressure plate while forming a green sand mold 34 and that inside the train 32 loaded greensand applied pressure value (peak pressure). The green sand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H are pressure sensors. In the present embodiment, the green sand shape shape sensors 10A , 10B , 10C , 10D in the four corners of the pressing surface of the upper pressure plate 33 embedded. In the present embodiment, the green sand shape shape sensors 10E , 10F , 10G , 10H in the four corners of the pressing surface of the lower pressure plate 34 embedded. The reason that the green sand mold shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H embedded in such a manner is the same as the reason described in the first embodiment.

In addition, the green sand shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H a pressure receiving surface for measuring pressure exerted in the pressing surface of the pressure plate 33 and the printing plate 34 is exposed, and to the pressing surface of the upper pressure plate 33 and the lower pressure plate 34 the applied pressing value (peak pressure). At this time, it is desirable that the pressure receiving surface of the green sand mold formation sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H and the pressing surface of the upper pressure plate 33 and the lower pressure plate 34 are in a flush state with no differences in level in between. Because of this, it is possible to measure the precise pressure.

The wiring 11 connects the mold quality evaluation device 12th with the green sand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H . In the present embodiment, the green sand shape shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H and the mold quality evaluation device 12th by cables over the wiring 11 connected, but can also be connected wirelessly. For example, it is possible to use wireless communication such as wireless LAN or Bluetooth, etc. to read the pressure value (pressing value data) obtained by the greensand shape forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H is detected to the mold quality evaluation device 12th to send.

The mold quality evaluation device 12th evaluates the quality of the by the mold forming device 29 green sand mold formed by the green sand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H measured pressure value (pressure value data). The mold quality evaluation device 12th comprises a receiving unit 15th , an amplification unit 16 , an input unit 17th , a mold strength calculation unit 18th , a mold quality determining unit 19th , a display unit 20th , a transmitter unit 21 and a recording unit 22nd .

The receiving unit 15th receives the through the greensand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H measured pressure value (pressure value data). The reinforcement unit 16 amplifies the signal amount of the received pressure value (pressure value data). The input unit 17th inputs: the mold strength of a molded green sand shape measured by a mold strength gauge; Values of a slope a and an intersection point b of the expression y = ax + b and a threshold value of the mold strength of a green sand mold to be molded, etc.

From the into the input unit 17th input mold strength and that of the green sand mold shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H measured pressure value (peak pressure) uses the Mold strength calculation unit 18th the relational expression between the mold strength and the measured values for calculating the mold strength for each pressure value (peak pressure) obtained by the green sand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H is measured.

The mold quality determination unit 19th determines the quality of a molded green sand shape from the threshold value in the input unit 17th the entered mold strength and the calculated mold strength. The display unit 20th displays on a screen: that by the greensand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H measured pressure value (peak value); Values of the slope “a” and the intersection point “b” of the relational expression y = ax + b between that by a worker using the input unit 17th entered mold strength and pressure value (peak pressure); the threshold value of the mold strength of a green sand mold to be molded, input by a worker; the mold strength calculation result and the mold quality determination result etc ..

The transmitter unit 21 sends problem determination data to the Patlite 23 etc .. The recording unit 22nd records pressure value data, mold strength data associated with pressure values, mold strength calculation results and mold quality determination results, etc.

(Method of Evaluating Mold Quality Using Mold Molding Apparatus)

Next, a description will be given of a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus 29 . 18th Fig. 13 shows steps in a method of evaluating mold quality (method of molding a green sand mold) using the mold forming apparatus 29 according to the second embodiment. It should be noted that in 18th a sand tank 36 to the in 16 mold forming apparatus shown 29 adjoins. A predetermined amount of green sand is added to the sand tank 36 loaded from the greensand transport device (not shown) and after being briefly held, a loading hole is closed and when pressurized air inside the sand tank 36 is fed, green sand is loaded by pouring it into the upper and lower mold forming spaces via green sand injection ports 35 , 35 in the coat 31 and the train 32 is blown.

1. 1. Wenn das Formen beginnt, bewegt sich der Zubringerwagen 30, der darauf die Platte 2 platziert aufweist, welche die Muster 2, 3 daran angebracht aufweist, aus dem in 18(a) gezeigten Zustand zwischen dem Mantel 31 und der Schleppe 32.
2. 2. Als Nächstes heben sich die untere Druckplatte 34, welche die darin eingebetteten Grünsandform-Formungssensoren 10E, 10F, 10G, 10H aufweist, und die Schleppe 32, heben die Platte 2 von dem Zubringerwagen 30 an und wenn der in 18(b) gezeigte Zustand eingestellt ist, wird Druckluft dem Sandtank 36 zugeführt und wird der Grünsand dadurch, dass er in die oberen und unteren Gussform-Formungsräume über die Grünsandeinblasdurchlässe 35, 35 im Mantel 31 und der Schleppe 32 eingeblasen wird, geladen.
3. 3. Als Nächstes, aufgrund der Aktion eines (nicht gezeigten) Zylinders pressen (komprimieren) die oberen und unteren Druckplatten 33, 34, die die darin eingebetteten Grünsandform-Formungssensoren 10A, 10B, 10C, 10D und 10E, 10F, 10G, 10H aufweisen, den Grünsand innerhalb des Mantels 31 und der Schleppe 32 und wird der in 18(c) gezeigte Zustand erzielt. Zu dieser Zeit messen die Grünsandform-Formungssensoren 10A, 10B, 10C, 10D und 10E, 10F, 10G, 10H die Druckwerte (Spitzendruck) an den Druckoberflächen der oberen und unteren Druckplatten 33, 34. Es ist anzumerken, dass Grünsandformen im vorliegenden Schritt geformt werden. Zu dieser Zeit sind die Grünsandform-Formungssensoren 10A, 10B, 10C, 10D und 10E, 10F, 10G, 10H zwischen dem Muster 3 und der Wand von jeweils dem Mantel 31 der oberen Druckplatte 33 und der Schleppe 32 der unteren Druckplatte 34. Zu dieser Zeit wird der gemessene Druckwert (Spitzendruck) an die Gussformqualitäts-Evaluierungsvorrichtung 12 gesendet und wird die Qualität der Grünsandform, die gerade geformt worden ist, evaluiert.

The molding of a green sand mold by the mold forming apparatus 29 follow the procedure below.

1. 1. When molding begins, the delivery trolley will move 30th who on it the plate 2 which has placed the pattern 2 , 3 has attached to it, from the in 18 (a) shown condition between the coat 31 and the train 32 .
2. 2. Next, the lower pressure plate will rise 34 showing the green sand shape formation sensors embedded therein 10E , 10F , 10G , 10H has, and the train 32 , lift the plate 2 from the delivery car 30th on and when the in 18 (b) is set, compressed air is added to the sand tank 36 and the green sand is fed into the upper and lower mold forming spaces via the green sand injection passages 35 , 35 in the coat 31 and the train 32 is blown in, loaded.
3. 3. Next, due to the action of a cylinder (not shown), press (compress) the upper and lower pressure plates 33 , 34 who have embedded the green sand shape shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H have the green sand within the mantle 31 and the train 32 and becomes the in 18 (c) shown condition achieved. At this time, the green sand shape formation sensors measure 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H the pressure values (peak pressure) on the pressure surfaces of the upper and lower pressure plates 33 , 34 . It should be noted that green sand molds are formed in the present step. At this time, the green sand mold shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H between the pattern 3 and the wall of the coat, respectively 31 the upper pressure plate 33 and the train 32 the lower pressure plate 34 . At this time, the measured pressure value (peak pressure) is sent to the mold quality evaluation device 12th and the quality of the green sand mold that has just been formed is evaluated.

Quality evaluation by the mold quality evaluation device 12th is performed after the expression y = ax + b, which represents the relationship between the mold strength and the peak value of the pressure of the green sand mold shape sensors, is determined in advance. In addition, a green sand mold flows through the mold quality evaluation device 12th has been determined to be OK as it is along the route, and subsequent steps (molten metal casting) are carried out. On the other hand, a green sand mold flows through the Mold quality evaluation device 12th has been determined to be defective as it is along the route, but the subsequent steps (molten metal casting, etc.) are not carried out. The green sand mold skips these steps and is shaken out of the mold as a casting mold to be discarded in the same way as a green sand mold for which the mold quality has been determined to be OK.

4. Next, the lower pressure plate descended 34 and the train 32 and if the plate 2 on the delivery car 30th is placed, a state is reached in which the patterns 3 , 3 removed from the top and bottom greensand molds. Then the delivery trolley moves 30th to the in 18A position shown and if the lower pressure plate 34 and the train 32 rise again, mold alignment of the upper and lower green sand molds is made by aligning the shell 31 and the train 32 executed. At this time, the upper and lower green sand molds are in a state of being pushed by the upper pressure plate 33 and the lower pressure plate 34 are sandwiched. From this state when the upper pressure plate 33 and the lower pressure plate 34 lower, the aligned upper and lower greensand shapes will be lowered and out of the mantle 31 and the train 32 removed to the in 18 (d) to achieve the condition shown.

5. The aligned upper and lower green sand molds are removed from the mold forming apparatus 29 transported to a route of the next step.

In addition, pressure value data, mold strength data associated with pressure values, mold strength calculation results, and mold quality determination results, etc. generated during the molding step are all stored in the recording unit 22nd the mold quality evaluation device 12th recorded. Therefore, it is possible to use these numerical values to determine the operating state of the mold forming apparatus 29 to monitor and these numerical values are in quality control, maintenance and troubleshooting of the mold forming apparatus 29 useful. Furthermore, these numerical values can lead to the early detection of causes of defects such as: sand spillage, burn-in of a casting and melt waste which occur due to loading defects, and swelling of the green sand mold due to molten metal pressure after casting.

Further, in the present embodiment, are the green sand shape shape sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H in the four corners of the printing surface of the upper and lower printing plates 33 , 34 near the coat 31 and the train 32 embedded. However, even if the number of green sand shape sensors installed in the upper and lower pressure plates 33 , 34 embedded is small, it is possible to calculate the relationship between the mold strength and the peak pressure of the green sand mold forming sensors. In this case, the accuracy is a little lower compared with the case where the green sand shape forming sensors are embedded in four places, but it is possible to cut the cost.

In this case it is also possible to have two places 10A , 10B or 10C , 10D on a line between opposite corners of the printing surface of the upper printing plate 33 , in the 17th shown is set, or two places 10E , 10F or 10G , 10H on a line between opposite corners of the pressure surface of the lower pressure plate 34 adjust. 19th and 20th show other examples where the printing surface of the upper pressure plate 33 green sand shape forming sensors embedded therein 10A , 10B having. In these drawings, 3a shown by two-dot chain lines represents the corresponding position of the pattern 3 on the plate 2 with the pattern attached to it in the mold forming space. In 19th are the two green sand mold shape sensors 10A , 10B near the central portion of the long sides of the pressure plate 33 embedded. In 20th are the two green sand mold shape sensors 10A , 10B near the central portion of the short sides of the printing plate 33 embedded. It is possible to use the shaping sensors 10E , 10F in the same state in the printing surface of the lower printing plate 34 to arrange. Due to the arrangement of these shape sensors, it is possible to prevent a bias in the amount of charge, etc. between right and left of the green sand injection passages 35 , 35 or at the proximity or distance of the green sand injection openings 35 , 35 to ensure.

Thus, according to the mold molding apparatus according to the second embodiment, the green sand mold molding sensors measure 10A , 10B , 10C , 10D the pressure (peak pressure) acting on the printing surface between the upper pressure plate 33 and that in the coat 31 charged greensand is applied, and the greensand shape sensors measure 10E , 10F , 10G , 10H the one on the printing surface between the lower pressure plate 34 and the one in the train 32 loaded green sand applied pressure value (peak pressure). Next, from the correlative relationship between the pre-measured mold strength and the peak pressure of the green sand mold forming sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H , calculates the mold strength calculation unit 18th the mold quality Evaluation device 12th the mold strength from the pressure value (peak pressure) measured by the green sand mold sensors 10A , 10B , 10C , 10D and 10E , 10F , 10G , 10H is measured for a subsequently formed green sand mold. Next, the mold strength calculating unit determines 18th the mold quality evaluation device 12th the quality of the mold from a preset threshold value of the mold strength and that determined by the mold strength calculation unit 18th calculated mold strength. Because of this, it is possible to individually calculate the mold strength of molded green sand molds without measuring using a mold strength gauge and further evaluate the quality of green sand molds.

Further, according to the mold molding apparatus of the second embodiment, one passes through the mold quality evaluation apparatus 12th Green sand mold determined to be defective does not follow the subsequent steps (molten metal casting, etc.), and is shaken out as a casting mold to be discarded. Therefore, it is possible to reduce defects in green sand molds produced. Furthermore, it is possible to avoid unnecessary labor and therefore it is possible to reduce the production cost.

Furthermore, according to the mold forming apparatus of the second embodiment, it is possible to make a determination of “good” or “bad” in terms of the quality of the molded mold for each flask, which can therefore lead to mold quality assurance for each flask .

Further, according to the mold forming apparatus of the second embodiment, pressure value data, mold strength data associated with pressure values, mold strength calculation results, and mold quality determination results generated during the molding step are all stored in the recording unit 22nd the mold quality evaluation device 12th recorded. Therefore, it is possible to use these numerical values to determine the operating condition of the mold forming apparatus 29 to monitor and these numerical values can be used in quality control, maintenance and fault detection of the mold-forming device 29 to be useful. Furthermore, the use of these numerical values can lead to early detection of causes of defects such as: sand spill, casting burn-in, and camber that occurs due to loading defects, and swelling of a green sand mold due to melt pressure after casting.

(Modifications)

In the first and second embodiments, after determining the relationship between the mold strength and the pressure value (peak pressure) from the measured compression mold strength and that by the green sand mold shape sensors 10A , 10B , 10C , 10D (and 10E , 10F , 10G , 10H ) measured pressure value (peak pressure) is calculated by the mold quality evaluation device 12th separated the mold strength from that determined by the green sand mold shape sensors 10A , 10B , 10C , 10D (and 10E , 10F , 10G , 10H ) measured pressure value (peak pressure). In addition, the quality of the molded green sand mold is determined from the preset threshold value for the mold strength and the calculated mold strength.

In addition, it is by returning results obtained by the mold quality evaluation device 12th can be determined on a kneading machine to precisely control the amount of water injected into the kneading machine. For example, if that by the green sand mold shape sensors 10A , 10B , 10C , 10D (and 10E , 10F , 10G , 10H ) the measured pressure value (peak pressure) is extremely low and, as a result of this, the mold strength is extremely low, the mold quality evaluation device determines 12th that the reason is because sand was not loaded uniformly within the mold and that the reason is that the CB value of the greensand is high, and by providing an instruction to the kneading machine to reduce the amount of water injected, it is possible to cancel the loading defect of the greensand.

Further, by returning to the kneading machine, by the mold quality evaluating device 12th According to certain results and from results obtained by the greensand automatic measuring system or the like, measuring and evaluating the compressive strength of the greensand, it is also possible to control the amount of additives, water, etc. loaded into the kneading machine. For example, it is possible to evaluate the flowability etc. of the green sand from: Properties of the green sand which are measured by the green sand automatic measuring system, such as compressive strength, permeability, compactability value, water content value etc. of the green sand, which is determined by the dynamic map information Generating unit 10D (and 10E , 10F , 10G , 10H ) measured pressure value (peak value) and its distribution. Further, by estimating the amount of additives, water content, etc. loaded during kneading, it is possible to fix mold defects.

Further, in the first and second embodiments, the mold quality evaluation device converts 12th the pressure value (peak pressure) obtained by the green sand mold formation sensors 10A , 10B , 10C , 10D (and 10E , 10F , 10G , 10H ) was measured into a mold strength and determines the quality of the molded green sand molds based on the converted mold strength and the measured mold strength. However, since it is ensured that there is a correlative relationship between the pressure value (peak pressure) and the mold strength, it is also possible to determine the quality of a green sand mold directly from the pressure value (peak pressure) without converting to the mold strength.

(Third embodiment)

21 (a) Fig. 13 is a vertical cross-sectional view of a mold forming apparatus which is the third embodiment of the present invention. 21 (b) shows pressure feet when viewed from line DD. Note that, in the embodiment described below, the same reference numerals are used in the drawings for configurations common to the first embodiment and the description thereof is omitted. In the third embodiment, pressure feet are used instead of a pressure plate. In the drawings, reference numbers refer to 300 on pressure feet. The pressure feet 300 are arranged in a rectangular shape and are components that form part of a boundary of the pressure feet 300 and the metal mold box 5 defined molding space during the green sand molding by the mold forming device 1 form. As in 21 (b) As shown, green sand shape formation sensors 101, 10J, 10K, 10L are embedded in individual pressure feet.

The embodiment shown in these drawings differs from the above-mentioned first embodiment in that pressure feet 300 used as elements that carry out the press action. Regarding the pressure feet 300 is made by positioning the pressure feet vertically 300 towards the pattern 3 according to the height of the pattern 3 and moving the pressure feet 300 during the pressing action, the height of the loaded greensand is adjusted and the compaction pressure is controlled to be the same at all pressure feet upon completion of the pressing.

As for example in 21 (a) Shown are pressure feet 300b , 300d that are too high sections of the pattern 3 point out, positioned so that they continue to the pattern 3 point out as there pressure feet 300a , 300c , 300e do that to lower sections of the pattern 3 point. When a mold space is essentially defined and green sand is being loaded, with the positions of these pressure feet 300a to 300e the way they are held (not shown), the amount of sand can be right under the pressure feet 300b , 300d can be made smaller than the amount of sand directly under the pressure feet 300a , 300c , 300e (Not shown). From this state while a print head 7th is lowered, the pressure feet become 300a to 300e moved to positions where ultimately all of the surfaces that make up the pattern 3 are aligned and the pressing step ends. By controlling the pressure feet in such a manner, it is possible to obtain a uniform rate of compression of green sand regardless of a difference in section in the height of the pattern (not shown) 3 to achieve.

Further, preliminary observations are made on the tendency of a loading state of greensand, not just the height of the pattern, and the vertical positions of the presser feet 300 aligned with a non-uniformity when loading the green sand. By controlling the press feet in such a way even if there is a pattern or even if sand loading tends to be non-uniform before pressing, it is possible to move the press feet by means of cylinders that cause vertical movement during and during green sand loading of pressing so that all pressure feet perform compression with the same force. This means that it is possible to alleviate "non-uniformity in sand introduction" (biases in the density distribution of the loading of green sand before compaction and in the loading height of green sand before compaction) on the basis of patterns, which is a disadvantage of use the printing plate was.

When a mold has been managed and formed normally by the above movements, those are by being in the pressure feet 300 embedded green sand shape forming sensors measured (peak) pressure values at all of the sensors. As such, when a measured pressure value during molding is out of variation in values observed in a normal state, it is believed that an abnormality has occurred due to some kind of cause. It is believed that these causes include extremely uneven sand introduction and malfunction of the cylinders that move the pressure feet.

Cases where the variation in these pressure values has become large are regarded as cases where a particular variation has occurred, and the molds are determined and processed in the mold quality evaluation device as FT.

For example, a method for determining a particular variation herein may be a case where a standard deviation in the Forming sensors, which are embedded in the pressure feet, measured pressure values is calculated during the formation of a casting mold and the standard deviation is greater than a predetermined reference value. This reference value can be set arbitrarily and, for example, can be initially set as a value that is considered appropriate in view of the mold quality.

Further, it is also possible to assume a particular variation as being a case where the variation is larger by 20% or more than the average of the standard deviations of the pressure values measured for the molds molded in the previous ten molding boxes. The number of previously formed molds to be averaged and the ratio of the extent to which the average is exceeded, which is a determining reference for particular variations, may be appropriately selected herein.

In this embodiment, except for the points described above, mold molding is performed by the same movements as those of the first embodiment, and the same functions and defects as those of the above-mentioned first embodiment are obtained.

The above-mentioned first, second and third embodiments are examples where two or more pressure sensors were provided in the pressure plate or the pressure feet. However, in the present invention, a configuration is also possible in which a pressure sensor is provided on the pressure plate or the pressure feet. In this case, it is desirable that the position where the pressure sensor is attached is close to the pattern of the plate. Further, in those cases where there is a pressure sensor, the output of the one pressure sensor also indicates a value related to the mold strength at a specific position of the mold. Therefore, the accuracy decreases, but it is possible to use this value to make an evaluation of the mold quality.

Various embodiments of the present invention are described above, but the above description does not limit the present invention, and various modifications can be considered including omitting, adding and replacing constituent elements within the technical scope of the present invention.

List of reference symbols

1

Mold Molding Apparatus (Flask Mold Molding)

2

plate

2a

Central plate

2 B

Peripheral plate

3

template

4th

carrier

5

Metal mold box

6th

Filling mold box

7th

Printhead

8th

printing plate

9

table

10A-10L

Greensand mold forming sensor

11

wiring

12th

Mold quality evaluation device

13th

Rifle

14th

bolt

15, 15 '

Receiving unit

16, 16 '

Reinforcement unit

17th

Input unit

18th

Mold strength calculation unit

19th

Mold quality determination unit

20th

Display unit

21

Sending unit

22nd

Recording unit

23

Patlite

24

Pressure value sending unit

25th

Integrated amplifier recorder

26th

computer

27

Lamella hopper

28

Lamella

29

Mold Molding Machine (Flaskless Molding Machine)

30th

Delivery trolley

31

coat

32

train

33

Upper pressure plate

34

Lower pressure plate

35

Green sand injection passage

36

Sand tank

300, 300a-300e

Pressure foot

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• JP 3415497 B [0004]
• JP 3729197 B [0004]

Claims (15)

A mold forming apparatus comprising: a green sand mold molding sensor that measures, during molding of a green sand mold, a pressure value applied to a contact portion between a pressure plate or pressure feet and green sand introduced into a mold molding space; and a mold quality evaluation device which estimates the quality of a green sand molded mold from the pressure value. The mold forming apparatus according to FIG Claim 1 wherein the mold quality evaluation device comprises a mold strength calculating unit that calculates the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured. The mold forming apparatus according to FIG Claim 2 wherein the mold quality evaluation device comprises a mold quality determination unit that determines the quality of a molded green sand shape from the calculated mold strength based on a predetermined threshold value. The mold forming apparatus according to FIG Claim 2 or 3 wherein the mold strength calculating unit calculates the mold strength of a green sand mold for which the mold strength has not been measured. A mold forming apparatus according to any one of Claims 2 to 4th wherein the mold quality evaluation device further comprises display means that displays the relationship, calculated by the mold strength calculating unit, between the pressure value and the mold strength of a green sand mold for which the pressure value was measured. A mold forming apparatus according to any one of Claims 1 to 5 wherein the mold quality evaluation device further comprises recording means that records pressure value data, mold strength data associated with pressure values, a calculation result of the mold strength, and a determination result of the mold quality generated during molding of a green sand mold. A mold forming apparatus according to any one of Claims 1 to 6th wherein transmission of a pressure value from the green sand mold forming sensor to the mold quality evaluation device is carried out via wireless communication. A mold forming apparatus according to any one of Claims 1 to 7th wherein the mold forming apparatus is a flaskless molding machine or a flask molding machine. A mold forming apparatus according to any one of Claims 1 to 8th wherein the pressure plate is configured to be rectangular, an array of the pressure feet is configured to be rectangular, a plurality of green sand shape shape sensors are provided, and these pressure sensors are embedded in the four corners of the pressure plate or in the pressure feet at the four corners . A mold quality evaluation device, during molding of a green sand mold, evaluates the quality of a molded green sand mold from a pressure value applied to a contact portion between a pressure plate or a pressure foot and green sand filled in the mold molding space. Mold quality evaluation apparatus according to FIG Claim 10 comprising a mold strength calculating unit that calculates the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured. Mold quality evaluation apparatus according to FIG Claim 11 comprising a mold quality determining unit that determines the quality of a green sand molded shape from the calculated mold strength based on a predetermined threshold value. A mold quality evaluation method comprising measuring, during molding of a green sand mold, a pressure value applied to a contact portion between a pressure plate or pressure feet and green sand filled in a mold molding space; and evaluating the quality of a green sand molded shape from the pressure value. Mold quality evaluation procedure according to Claim 13 wherein evaluating the quality of a green sand mold comprises calculating the mold strength of a green sand mold from the pressure value based on a relationship between the pressure value and the mold strength of a green sand mold for which the pressure value was measured. Mold quality evaluation procedure according to Claim 14 , wherein evaluating the quality of a green sand mold comprises determining the quality of a molded green sand mold from the calculated mold strength, based on a predetermined threshold.

Images