JPH04190964A - Flaskless casting line - Google Patents

Abstract

PURPOSE:To secure a position of an arbitrary sand mold in a sand mold line on an intermittent feeder by picking up the image of a boundary area between adjacent sand molds of the sand mold line in a flaskless casting line. CONSTITUTION:In the flaskless casting line provided with a molding machine 1, an extruding machine 2, an intermittent feeder 3, the boundary area between the adjacent sand molds to be carried in the sand mold line is picked up by TV cameras 4a, 4b, the video signals are processed, the boundary line between the adacent sand molds is decided, the length of the sand mold in the feeding direction is decided by a width between two boundary lines in the feeding direction. In this way, the position of the arbitrary sand mold in the sand mold line on the intermittent feeder 3 can be decided based on this sand mold length.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a frameless casting line.

[Prior art] In a conventional frameless casting line, a sand mold making machine, a sand mold extruder, a pouring machine, a casting removal device, a sand recovery machine, etc. are arranged along an intermittent conveying device for conveying sand molds that is operated at intervals. has been done. The sand mold row on the intermittent conveying device is made up of frameless sand molds connected in a row, and a sprue that communicates with the internal cavity is opened at the center of the upper surface of the boundary between adjacent sand molds.
Molten metal is sequentially poured from a pouring machine into the Nth sprue from the end of the sand mold row.

In this pouring process, it is natural that the alignment between the pouring cylinder of the pouring machine and the sprue is very important.
No. 150 discloses that the width of the sand mold is detected by the piston stroke of the press in the sand mold making machine, and the position of the sprue in the conveyance direction near the pouring machine is detected by the sum of a predetermined number of consecutively detected piston strokes, Then, the tip of the pouring tube of the pouring machine is moved to the detected position to align the pouring tube and the sprue.

[Problems to be Solved by the Invention] However, the conventional technique in which the piston stroke of the sand mold making machine described above is regarded as the sand mold width and a predetermined sprue position is detected from the sum thereof has the following problems.

That is, the sand mold produced by the sand molding machine is pressed against the end of the sand mold row by the sand mold extruder, or at this time, the sand mold shrinks, causing the width of each sand mold to vary, and the sum of the widths to vary.

Secondly, in the device disclosed in the above-mentioned publication, after the latest sand mold is pressed against the end of the sand mold row by the piston of the press of the sand mold making machine, this sand mold row is pushed out in the conveying direction, but the conveyance of the sand mold row is intermittent. When a conveyance device is used, there are variations in the conveyance distance each time the intermittent conveyance device is used, and therefore the end position of the sand mold row varies each time the intermittent conveyance device is conveyed. Even if the width of several sand molds was closed, the end position of the sand mold row could not be confirmed, so the position of the sprue to pour the metal could not be determined.

Such problems also occur when detecting sprue gates or when detecting the post-casting removal position based on the boundary line between adjacent sand molds at a predetermined number in a sand mold array.

The present invention has been made in view of these problems, and provides a frameless casting line that can accurately determine the position of a predetermined part of a sand mold of a predetermined size in a frameless sand mold row on an intermittent conveying device. Its purpose is to.

[Means for Solving the Problems] The frameless casting line of the present invention includes a molding machine that molds sand molds, and an extruder that extrudes the molded sand molds in one direction to form rows of sand molds that are closely aligned with each other. , in a frameless casting line equipped with an intermittent conveying device that intermittently conveys the sand mold rows in the arrangement direction, an imaging means that images a boundary area between adjacent sand molds in the sand mold row being transported and outputs a video signal; a boundary line determining means for determining a boundary line by processing the video signal corresponding to the boundary area; and a sand mold length for determining a sand mold width in the conveying direction from widths in the conveying direction of two boundary lines adjacent in the conveying direction. The present invention is characterized by comprising a determining means and a position determining means for determining the current position in the transport direction of a predetermined portion of a predetermined sand mold in a sand mold row based on the determined width of each sand mold.

In one preferred aspect, the boundary line determining means can binarize the video signal and determine the boundary line from the width in the transport direction of the binary signal area corresponding to the boundary area.

In a preferred embodiment, the boundary line determining means may not extract the temporary boundary point if the width in the transport direction of the binary signal area corresponding to the boundary area exceeds a predetermined width.

In a preferred aspect, the boundary line determining means sets the median value of the width in the transport direction of the binary signal area corresponding to the boundary area as a temporary boundary point, and determines a plurality of temporary boundary points in a direction perpendicular to the transport direction, The boundary line may be determined from the plurality of obtained temporary boundary points.

In a preferred aspect, the boundary line determining means can set the current positions in the transport direction of the plurality of determined temporary boundary points as passing points of the boundary line.

[Operation] In the frameless casting line of the present invention, the intermittent conveyance device intermittently conveys the frameless sand mold rows.

The imaging means images the boundary area between adjacent sand molds of a predetermined number in the row of sand molds being conveyed, and the boundary line determining means processes the video signal to determine the boundary line between the adjacent sand molds. The sand mold width determining means determines the sand mold width in the transport direction from the width in the transport direction of two boundary lines adjacent in the transport direction, and the position determining means determines a sand mold width in the sand mold row based on the determined width of each sand mold. The current position of a predetermined portion of the sand mold in the transport direction is determined.

[Example code] DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to drawings.

As shown in Fig. 1, this frameless casting line consists of a sand mold making machine 1 that creates sand molds, and an extruder that extrudes the molded sand molds 100 in one direction to form rows of sand molds 200 that are closely aligned with each other. (Ejector) 2, an intermittent conveying device 3 that intermittently conveys the sand mold rows 200 in the arrangement direction, and images the boundary area 300 between adjacent sand molds 100 and 100 in the sand mold row 200 being conveyed, and outputs a video signal. It is equipped with TV cameras (imaging means in the present invention) 4a and 5a, and a calculation unit 5 that determines the sprue position based on the sand mold width calculated by processing the video signal.

As shown in FIG. 3, the sand molding machine 1 includes an intermittent conveying device 3
The upper hopper 11
, press 12.13 below hopper 11, hopper 11
It consists of an elevator 14 directly below.

The extruder 2 is a hydraulic drive device that is provided below the press 13 and extrudes the molded sand mold forward in the transport direction and presses it against the end of the sand mold row 200 on the intermittent transport device 3.

The intermittent conveyance device 3 is a so-called walking beam type conveyance device, and is operated in intervals, with an operation time of 2.2 seconds and a suspension period of 8.8 seconds. Handles hot water and castings.

A frameless sand mold row 200 formed by connecting approximately 200 sand molds 100 in a row is placed on the intermittent conveying device 1, and castings are placed at the boundary 300 of two adjacent sand molds 100. A cavity (not shown) for the product is formed;
A substantially rectangular sprue 400 communicating with each cavity is located at the boundary portion 3.
00 (see Figure 1). The standard dimension of one sand mold 100 in the conveyance direction is, for example, approximately 4Qcm, and the intermittent conveyance device 3 moves a distance equal to this dimension each time.
The frameless sand mold row 200 is advanced.

The TV cameras 4a and 5a each have a built-in CCD area sensor, and are disposed on the side of the upstream portion of the intermittent conveyance device, image the boundary area 300, and send the video signal to the comparator 51.
52 to the arithmetic unit 5.

The calculation unit 5 includes a microcomputer device 5 for image processing, and determines the sprue position based on the sand mold width calculated by processing the video signal. The calculation unit 5 serves as a boundary line determining means, a sand mold width determining means, and a position determining means in the present invention.

Hereinafter, the operation of the present invention will be explained with reference to FIGS. 3 to 5.

First, the sand mold making machine 1 creates a sand mold.

That is, as shown in FIG. 4, sand is dropped from the hopper 11 onto the frame 15 on which the elevator 14 is placed.

At this time, the front and rear of the frame 15 are surrounded by covers (not shown) to prevent sand from escaping from the front and rear of the frame 15.

Then, inside this cover, a press 12.13 compresses the sand inside the frame 15, and this compression causes the press 12.13 to compress the sand inside the frame 15.
A front mold 16 and a rear mold 17 provided at the tip of the piston 13 form a half cavity on the front and rear surfaces of the sand mold 101 (see FIG. 5).

Then the presses 12.13 move back and forth and the elevator 1
4 lowers the frame 15 and the sand mold 101 inside it (see FIG. 6).

Next, the extruder 2 pushes the sand mold 101 forward to move the sand mold 101 from the frame 15, and then presses the sand mold 101 against the rear surface of the sand mold 100 at the end of the sand mold row 100. Note that during this pressing, the extruder 2 uses a photointerrupter type optical sensor (not shown) to control the sand mold 1.
A gap between the rear surface of the sand mold 101 and the front surface of the sand mold 101 is detected, and the extruder 2 is stopped a short time after the gap disappears (see FIG. 7).

After that, the extruder 2 is moved backward, the intermittent conveyance device 3 is conveyed once, the core is stored in the rear half cavity, and the elevator 14 is raised (see Fig. 8).
Repeat the steps in the order shown.

Next, the operation of the calculation section 5 will be explained with reference to the flowchart in FIG.

First, initial settings are made using Sl, and the extruder 2 or the latest sand mold is moved forward and waited until it comes into contact with the end of the sand mold row and stops (S2).

Next, one frame of video signals from each of the TV cameras 4a and 4b is output to the calculation section 5. Here, the TV camera 4a images the boundary area of the sand molds 100 and 101, and the TV camera 4b images the boundary between the sand mold 101 and the tip surface of the piston of the extruder 2 (s3).

Next, the TV camera 4 is
Process the binary video signal of a to determine the boundary line 300 between the sand molds 100 and 101 (S4) Next, the determined boundary line 300 and the piston tip surface C of the extruder 2 (see Fig. 2) ) (see Figure 10) is calculated (S5
). In addition, l! of both TV cameras 4a and 4b! ii. Since the standard distance 1o between the center points m1 and m2 of the image screen (see Fig. 10) is fixed and known, the distance ΔL1 in the transport direction between the center point m1 and the field line 300, and the distance ΔL1 between the center point m2 and the piston Find the conveyance direction distance ΔL2 between the tip surface C and L=Lo
Calculate the sand mold width from the formula 1ΔL1+ΔL2.

Next, the positions of the boundaries between the 10th and 11th sand molds from the end of the sand mold row 100 are determined by adding up the rings of the 10 sand molds from the end of the sand mold row 100 ( S6).

That is, if the sum of each ring of the 10 sand molds is A, then the piston tip surface C that is currently being imaged by the TV camera 4b
The current position is a position displaced from the center point m2+ΔL2 to the downstream side in the conveyance direction by the above amount, or a position on the boundary line.

Next, the position on the boundary line is displayed and outputted to a pouring machine (not shown), which moves the pouring cylinder in the transport direction and pours the melt into the sprue.

In the above embodiment, one boundary line is the tip end surface of the piston of the extruder 2 (at the time of stopping after advancing), but of course, the boundary line is the Nth (N is an integer) sand mold and the N+1th sand mold in the sand mold row 100. It is also possible to detect the boundary line between the sand mold and the boundary line between the N+1-th sand mold and the N+2-th sand mold, and calculate the distance between them.

Next, the boundary line 3 is determined by the boundary line determination subroutine (S4).
The method for determining 00 will be further explained based on FIGS. 11 to 13.

The binary video signal sent to the arithmetic unit 5 via the comparator 51 is as shown in FIG.

That is, since the boundary area 600 is recessed, the threshold value of the comparator 51 and the adjustment of the illumination result in a black level, and the surface of the sand mold 100.101 becomes a white level (first
See Figure 2>.

First, extract the two edges 700 and 800 (320
>. Next, the current position x"1m of the edge 700 in the horizontal direction of the screen and the current position X2m of the edge 800 in the horizontal direction of the screen are determined (S21>. , and the position x2 of the edge 800 in the screen horizontal direction, calculate the average of each x1, and calculate the average of each x2.

Next, the midpoint between the determined current position x1m and current position x2m in the conveyance direction (screen horizontal direction) is determined as the boundary line position (S22>).

In this way, even if some error occurs in the edges 700 and 800, the influence of the error can be reduced by averaging.

As shown in FIG. 14, after 321, it is checked whether the distance between x1 and x2 found for each horizontal scanning line is within a predetermined range (331). The process proceeds to S22, and if there is no such horizontal scanning line, it is also preferable to omit the horizontal scanning lines x1 and x2 and not use them in calculating the average value. (3
32). In this way, erroneous detection due to landslides can be prevented.

[Effects of the Invention] As explained above, the frameless casting line of the present invention images the boundary area between adjacent sand molds in a row of sand molds being conveyed, processes the video signal, and processes adjacent sand molds. Determine the boundary line between the sand molds, determine the sand mold length in the transport direction from the width of the two boundary lines in the transport direction, and determine the position of any sand mold in the sand mold row to be drilled on the intermittent transport device based on this sand mold length. can do.

In particular, in the present invention, the width of the sand mold is measured after the latest sand mold is pressed into contact with the end of the sand mold row by an extruder, so that the influence of shrinkage of the sand mold due to the above-mentioned pressing can be avoided.

Furthermore, even though the sand mold rows are transported by the intermittent transport device, the starting position of the sand mold rows can be set to the boundary line position imaged by the imaging means, so even if the conveyance distance of each time of the intermittent transport device varies. It becomes possible to determine the position of the sand mold of a predetermined value from the position of the imaging boundary line.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a frameless sand mold array, Fig. 2 is a block diagram showing an embodiment of the present invention, Figs. 10 and 11 are views showing the imaging screen, FIG. 12 is an enlarged plan view of the boundary area, and FIGS. 13 and 14 are flowcharts showing the boundary line determination subroutine. . 1...Sand mold making machine 2...Extruder 3...Intermittent conveyance device 4a, 4b/TV camera (imaging means) 5...Calculating section (boundary line determining means, sand mold width determining means, position determining means ) Patent applicant Aisin Takaoka Co., Ltd.

Claims (5)

[Claims] (1) Equipped with a molding machine that molds a sand mold, an extruder that extrudes the molded sand mold in one direction to form rows of sand molds in close contact with each other, and an intermittent conveyance device that transports the rows of sand molds intermittently in the arrangement direction. In the frameless casting line, there is provided an imaging means for capturing an image of a boundary area between adjacent sand molds in a row of sand molds being conveyed and outputting a video signal, and processing the video signal corresponding to the boundary area to define a boundary line. sand mold width determining means for determining a sand mold width in the transport direction from widths in the transport direction of two boundary lines adjacent in the transport direction; A frameless casting line, comprising: position determining means for determining the current position of a predetermined portion of a predetermined sand mold in the conveyance direction; (2) The frameless type according to claim 1, wherein the boundary line determining means binarizes the video signal and determines the boundary line from the width in the transport direction of a binary signal area corresponding to the boundary area. casting line. (3) The computer according to claim 2, wherein the boundary line determining means does not extract the temporary boundary point when the width in the transport direction of the binary signal area corresponding to the boundary area exceeds a predetermined width. Frame casting line. (4) The boundary line determining means sets the median value of the width in the transport direction of the binary signal region corresponding to the boundary area as a temporary boundary point, and determines a plurality of temporary boundary points in a direction perpendicular to the transport direction;
3. The frameless casting line according to claim 2, wherein said boundary line is determined from a plurality of determined temporary boundary points. (5) The frameless casting line according to claim 4, wherein the boundary line determining means determines an average position in the transport direction of the plurality of temporary boundary points determined as a passing point of the boundary line.