JPH0416261B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention is an automatic pouring machine that automatically pumps up molten metal and pours it into a mold. Regarding the fixed point pouring device of the machine. (Prior art) In an automatic pouring machine, considering the case where the sprue of the mold to be poured is small, it is necessary to make the pouring point as fixed as possible and to narrow the splash range. Therefore, various fixed point pouring methods have been proposed. An example of a conventional fixed point pouring method of this type is one using a device disclosed in Japanese Utility Model Application Laid-Open No. 56-65765. This device is shown in Figures 8 and 9.
As shown in the figure, mounting earths 2, 2 are provided protruding from both tips of a pair of support columns 1, 1, respectively, and mounting pieces 4 protruding from both sides of the tip of a ladle (ladle) 3 are attached to the upper end thereof.
to be pivoted. Then, the spout 6 of the spout 5 of the ladle 3 is placed on the line connecting the two pivot points 7, 7. A projecting piece 8 is also provided at the center of the rear end of the ladle 3, and the lower end of a lifting rod 9 is pivotally connected thereto. Further, the upper surface of the front end of the lid 10 is partially hollowed out to form an opening 11. To pour molten metal using this device, the rod 9 is pulled up, the ladle 3 is tilted forward, and the molten metal is poured out from the spout 5. At this time, in the ladle 3, the tip 6 of the outlet 5 is on the line connecting the two pivot points 7, 7, which are the rotation centers of the ladle 3, so even if the ladle 3 is tilted forward, the outlet 5 The tip of the mouth 6 does not move. That is, in this type of pouring method, the flowing molten metal always falls from a fixed position regardless of the inclination of the ladle 3. Another example of a method for making the pouring point a fixed point is to use an industrial robot as an automatic pouring machine. In this method, a ladle is attached to the arm of an industrial robot, and the arm tilts the ladle, while at the same time moving the ladle back and forth with respect to the mold sprue so that the pouring point is a fixed point. . This pouring operation is taught to the industrial robot in advance. (Problems to be Solved by the Invention) However, in the pouring method in which the ladle spout is located at the center of rotation of the ladle, if the pouring speed, that is, the rotation speed of the ladle, is extremely slow, the pouring point may be This is a fixed point, but if the rotational speed is increased in consideration of productivity and pouring conditions, a problem arises in that the range of hot water splashing increases. This is due to the fact that the outlet of the ladle is a fixed point, and the experimental method and results are shown in FIGS. 5 and 7. This is ω=4.3de
Molten metal is poured by tilting the ladle at a rotational speed of g/s, and l ₁ indicates the distance between the position where the molten metal flew and the ladle outlet, and l ₂ indicates the distance between the position where the molten metal flew and the ladle outlet. This shows the pouring width 75mm below the outlet. As can be seen in FIG. 7, at the middle of the pouring process, the hot water splash distance _l1 is greater than at the start and end of the hot water pouring, and moreover, the hot water splash range _l2 is greatly expanded. Next, in pouring methods using industrial robots, the ladle can be moved back and forth relative to the mold sprue, making it possible to set the pouring point at a fixed point. In addition to this, it is also necessary to teach movement in the forward and backward directions according to the rotation angle, and the teaching becomes multi-axis and complicated. Furthermore, this movement in the front-rear direction must be finely adjusted depending on the rotation angle of the ladle, creating the problem that teaching is extremely difficult and requires skill. The present invention has been made in view of the above problems, and an object of the present invention is to provide a fixed point pouring method that allows the pouring point to be easily set as a fixed point. (Means for solving the problem) As a means for solving the above problem, as shown in FIG. 1 and FIG. Mechanism 15
, and one link 31 of the quadrilateral link mechanism, which faces the ladle, is extended parallel to the upper surface of the ladle and by approximately the same length as the distance connecting the tip of the ladle and its midpoint. Then, attach the extended end to the rotating shaft 33 at the tip of the arm 14 of the automatic pouring machine main body.
In the quadrilateral link mechanism, the length (l) of the one link is set larger than the length connecting the two pivot points of the ladle, and the length (l) of the one link with respect to the horizontal line is The inclination angle (β) is
Driving means 21, 23, 28 which is set larger than a similar inclination angle connecting two pivot points, and which causes the arm to rotate the link mechanism about the rotation axis.
It was designed to provide a. (Operation) The above configuration functions as follows. After the ladle that has drawn up the molten metal is moved to the sprue of the mold, a link mechanism is activated to tilt the ladle and pour the molten metal. At this time, the distance from the tip of the ladle (pouring spout) will be greater during the middle of pouring than at the start and end of pouring, but due to the quadrilateral link mechanism, the ladle will temporarily move according to its inclination. After moving backward, it moves forward, and as a result, the pouring point remains constant. By doing so, the molten metal can be poured into the sprue without spilling it to the outside. (Example) Next, an example of the present invention will be described based on the drawings. FIG. 3 is a perspective view showing an automatic pouring system having an automatic pouring machine 12 according to the present invention. To roughly explain this configuration, the main body 13 of the automatic pouring machine 12
A rotatable arm 14 is attached to the
A ladle 16 is attached to the tip of the arm 14 via a quadrilateral link mechanism 15, which is the essential part of the present invention. On the floor, there is a furnace 17 for melting the casting material.
and molds 18, 18 having sprue 18a on the upper surface...
A rotary table 19 on which ... is mounted is attached. Note that 20 is a control section of the automatic pouring machine. Next, the link mechanism 15, which is a main part of the present invention, will be explained using FIGS. 1 and 2. The arm 14 of the automatic pouring machine main body 13 is provided with an actuator 21 such as a motor or a cylinder device, and the drive shaft 2 of the actuator 21
2 is engaged with a long hole 24 of an arm member 23 via a pin 25. Further, the arm member 23 is attached to a rotating shaft 27 that is rotatably attached to a fixed member 26 fixed to the arm 14, and one end of the first link 28 is fixed to this rotating shaft 27. ing. One end of a second link 30 that is rotatable is attached to the other end of the first link 28 via a joint shaft 29, and the other end of the second link 30 is rotatable to the center of the upper end of the ladle 16 (center point). It is attached to the shaft. Further, an intermediate portion of a third link 31 is rotatably attached to an intermediate portion of the second link 30 via a joint shaft 32 . Also, the third link 3
1 is extended parallel to the upper surface of the ladle 16 and approximately the same length as the distance connecting the tip of the ladle 16 and its midpoint, and the extended end thereof is rotated to the lower end of the aforementioned fixing member 26. It is rotatably attached via a shaft 33, and a fourth link 34 is attached to the other end.
One end is rotatably attached via a joint shaft 35. The other end of the fourth link 34 is the ladle 16
It is rotatably attached to the rear end of the An adjustment screw 36 is provided between the joint shaft 32 and the joint shaft 35 of the third link 31, which can adjust the length l between them. Next, the operation of this link mechanism 15 will be explained. When the actuator 21 operates and the drive shaft 22 extends, the first link 28 rotates counterclockwise in the figure and moves the second link 30 upward.
Accordingly, the third link 31 is rotated counterclockwise in the figure around the rotating shaft 33. And the third
The fourth link 34 attached to the tip of the link 31 is also moved upward;
Since the amount of movement is larger in the case of , the rear end portion of the ladle 16 is lifted and the ladle 16 is tilted. At this time, the ladle 16 moves in the middle of the pouring, being moved further back than at the start and end of pouring. An experiment regarding this locus of movement is shown below. In the link mechanism 15 in FIG. 1, dimensions l, β
The spout 16a of the ladle 16 after changing the
The trajectory of is experimentally determined, and the results are shown in Fig. 4. Note that the dimensions l and β are set to the values shown in Table 1.

【table】

[Table] Figure 4 shows the inclination angle of the ladle 16 and the horizontal position of the spout 16a of the ladle 16 at that inclination angle (the position of the spout 16a before the link mechanism operates is 0) for the link mechanism of each dimension. The forward direction of the ladle is + and the backward direction is -. In the experiment shown in Fig. 5, within this trajectory, when tilting the ladle 16 at a rotational speed ω = 4.3 deg/s, if a link mechanism with the dimensional relationship is used, the result will be as shown in Fig. 6. Pouring can be done so that the hot water point is almost at a fixed point. In addition, the following is understood from the experimental results shown in FIG. When only the length of l is changed with the link angle β = 11.6° (constant), the shorter the length of l, the more the spout 16a of the ladle 16 moves forward as the inclination angle θ of the ladle 16 increases. do. Furthermore, when the link length l = 148 (constant) and the angle β is changed from 11.6° to 25°, the ladle 16 moves backward as the inclination angle θ of the ladle 16 increases. do. By utilizing the above characteristics, even if the pouring pattern (ladle inclination speed, ladle spout shape, pouring amount, etc.) is changed, the dimensions of l and β of the link mechanism 15 can be appropriately selected and the pouring point can be adjusted. It is possible to pour molten metal by moving the spout 16a so that it is at a fixed point. Further, the line connecting the tip 16a of the ladle 16 and the rotating shaft 33 is approximately parallel to another link 30 whose one end is pivotally supported at the intermediate point a of the ladle, so that the amount of vertical fluctuation of the tip 16a of the ladle is is extremely small. In other words, the tip of the ladle can be set close to the sprue, and as a result, the molten metal can be poured without spreading, making it possible to pour into small sprues as well, and keeping the yield as high as possible. This will lead to improved performance. Next, the operation of this automatic pouring system will be explained. First, the arm 14 of the automatic pouring machine main body 13 moves up and down, and the ladle 16 pumps up molten metal from the furnace 17.
Subsequently, when the arm 14 rotates and moves the ladle 16 above the sprue 18a of the mold 18, the arm 1
An actuator 21 in 4 actuates the linkage 15. Then, at the same time as the ladle 16 is tilted, the spout 16a of the ladle 16 is moved back during the middle of pouring compared to when pouring starts and ends when pouring. In this way, with the pouring point as a fixed point,
Molten metal can be poured into the sprue 18a of the mold 18 without spilling it. When pouring into one mold 18 is completed, the arm 14 returns to its original position and pumps up the molten metal into the ladle 16 by performing the same operation as described above. In addition, rotary table 1
9 rotates and the next mold 18 is moved to the pouring position. In this way, the ladle 16 is moved to the furnace 17 one after another.
The molten metal is pumped up and poured into the mold 18. (Effects of the Invention) The present invention uses a unique link mechanism to move the tip of the ladle back and forth without vertically moving it much according to the inclination of the ladle, thereby fixing the pouring point at a fixed point. This allows pouring into molds with small sprues without spilling molten metal. Furthermore, by simply changing the dimensional relationship of the link mechanism according to the tilting speed of the ladle, various pouring patterns (ladle tilting speed, ladle spout shape, pouring amount, etc.) can be accommodated. Further, since a link mechanism is used, the structure and control are simplified, and costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a front view of a link mechanism which is a main part of a fixed point pouring device of an automatic pouring machine according to the present invention, and FIG. 2 is a diagram showing the operating state of the link mechanism of FIG. 1.
FIG. 3 is a perspective view showing an automatic pouring system equipped with the link mechanism shown in FIG. 1, and FIG. 4 shows the ladle inclination angle when the dimensions of l and β of the link mechanism shown in FIG. Figure 5 is a front view showing the experimental conditions of the ladle inclination angle and hot water splash range, and Figure 6 is the link mechanism shown in Figure 1. Figure 7 shows the experimental results when the experiment shown in Figure 5 was carried out using a link mechanism whose dimensions l and β were set as shown in Table 1. A diagram showing the experimental results when the experiment shown in FIG. 5 was conducted using a conventional device, FIG. 8 is a plan view of the device showing an example of the conventional technique, and FIG. It is a front view. 14...Arm, 15...Link mechanism, 16...
...Raddle.

Claims (1)

[Claims] 1 A quadrilateral link mechanism 15 is formed with the middle point and rear end of the ladle 16 as two pivot points, and one link 31 of the quadrilateral link mechanism, which faces the ladle, is parallel to the upper surface of the ladle. and extending it by approximately the same length as the distance connecting the tip of the ladle and its intermediate point, and pivoting the extended end to the tip of the arm 14 of the automatic pouring machine body using a rotating shaft 33, The quadrilateral link mechanism has a length (l) of the one link.
is set to be larger than the length connecting the two pivot points of the ladle, and the inclination angle (β) of the one link with respect to the horizontal line is set to be larger than the similar inclination angle connecting the two pivot points, and A fixed point pouring device for an automatic pouring machine, characterized in that an arm is provided with drive means 21, 23, and 28 for rotating the link mechanism about the rotation axis.