JPH03142038A - Molding machine - Google Patents

Abstract

PURPOSE:To easily and uniformly mold the whole molding sand to the necessary hardness by charging the molding sand into a molding flask and a raising flask and pressing the molding sand with upper and lower base plates after descending a frame body forming inner wall lower end part as reverse tapered shape along the check middle flask. CONSTITUTION:The molding sand 11 is charged into the molding flask 4 and the check middle flask 5 laid on the lower base plate having a pattern 2. After executing the sand cutting to this molding sand 11 along the check middle flask 5, a squeeze cylinder 1 is worked upward as extending to ascend the lower base plate 3. By this method, the molding sand 11 is pressed with the upper and lower base plates 3, 6 to form the mold. In the above molding machine, the frame body 8 forming the inner wall lower end part as reverse tapered shape is liftably inserted at between the check middle flask 5 and the upper base plate 6. After executing the sand cutting, the frame body 8 is descended with working of a cylinder 9 until the reverse tapered part engages with molding flask 4. By this method, the molding sand 11 in the raising flask 5 is shifted to center direction and packed under high density condition. After that, by executing pressing of the upper and lower base plated 3, 6, the whole molding sand 11 is made to the necessary hardness.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in a mold making device, and more particularly, to a mold making device that can make mold hardness substantially uniform.

(Prior art) Conventionally, after a casting flask is placed on a lower surface plate having a model, molding sand is poured into the flask, and a molding sand pressing piece is provided on the flat upper surface plate or on the periphery. Molding is made by compacting the molding sand using an upper surface plate (for example, Utility Model No. 54-13472)
Publication No. 8).

(Problems to be Solved by the Invention) When molding sand is introduced into the flask from above the model, the sand density above the model is high and the sand density near the flask is low. Therefore, the upper surface of the molding sand is compacted using an upper surface plate to make the mold hardness uniform, but the hardness of the molding sand is not uniform, and the molding sand above the top of the model is hard, and the molding sand near the flask is hard. Since sand is soft, there are problems in that mold deformation occurs during the transportation process or over time, and firmness occurs due to casting pressure. The present invention has been made to solve these problems and provides a mold making device that can uniformize the hardness of the mold near the flask and make the entire molding sand a desired hardness.

(Means for Solving the Problems) The mold making device of the present invention includes a frame body that can be raised and lowered between the joint frame and the upper surface plate, and the lower end of the inner wall of the frame body is formed in a tapered shape. It is something.

(Operation) After pouring molding sand into the flask and joint frame, when the frame is lowered until the tapered part of the frame engages with the flask, the molding sand in the joint frame moves toward the center of the joint frame. The molding sand is moved to fill the molding sand near the frame in a high-density state, and then the molding sand is pressed by the upper and lower surface plates, so that the entire molding sand has the required hardness.

(Example) FIG. 1 shows a mold making apparatus according to the present invention.

A lower surface plate 3 having a model 2 is connected to a squeeze cylinder 1 that can be raised and lowered freely, and a rectangular casting flask 4 and a joint frame 5 are placed on the lower surface plate 3. Above the joint frame 5 is a frame 7.
An upper surface plate 6 attached to the upper surface plate 6 is provided, and a rectangular frame 8 is interposed between the joint frame 5 and the upper surface plate 6. Upper surface plate 6
Four downward-facing frame cylinders 9 are installed around the frame 8, and the cylinders 9 are connected to the four corners of the upper surface of the frame 8.
The lower end of the inner wall of the cast member is formed into a tapered shape so that the lowered frame body 8 and the flask 4 can be engaged with each other via the tapered portion. Further, four downward-facing connecting plug cylinders 10 are arranged near the frame cylinder 9, and the cylinders 10 are connected to the four corners of the upper surface of the connecting frame 5.

Next, we will discuss the operation.

Molding sand 11 is put into the flask 4 and joint frame 5 placed on the lower surface plate 3, and after cutting the molding sand 11 along the joint frame 5, the frame cylinder 9 is extended downward. When the frame body 8 is lowered until the tapered part of the frame group 8 engages with the flask 4, the molding sand 11 in the joint frame 5 moves toward the center of the joint frame 5, and the molding sand 11 in the vicinity of the frame body 8 moves toward the center of the joint frame 5. The molding sand 11 is filled in a high density state.

Next, after releasing the hydraulic pressure of the frame cylinder 9 and the joint plug cylinder 10, the squeeze cylinder 1 is extended upward to raise the lower surface plate 3, and the molding sand 11 is transferred to the upper and lower surface plates 3.
．． 6, the entire molding sand 11 has the required hardness.

After the molding sand 11 hardens, the joint plug cylinder 10 is contracted upward to raise the joint frame 5, and then the frame cylinder 9 is contracted upward to raise the frame 8, and the squeeze The cylinder 1 is contracted downward and the lower surface plate 3
When the mold is lowered and the flask 4 is taken out from the lower surface plate 3, a mold as shown in FIG. 2 is obtained. After that, another empty flask 4
is placed on the lower surface plate 3, and the connecting plug cylinder 10 is extended downward to align the connecting frame 5 and the casting flask 4.

(Effects of the Invention) According to the present invention, a frame body that can be raised and lowered is interposed between the joint frame and the upper surface plate, and the lower end of the inner wall of the frame body is formed into a tapered shape, which requires a large amount of energy. The entire foundry sand can be easily made to the required hardness without being hardened.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of the mold making device according to the present invention;
FIG. 2 is a sectional view showing the formed mold. 5... Joint frame, 6... Upper surface plate, 8... Frame body.

Claims (1)

[Claims] In a mold making device that presses molding sand by a lower surface plate and an upper surface plate on which a casting flask and a joint frame are placed, a frame body that can be raised and lowered is interposed between the joint frame and the upper surface plate, and the frame body A mold making device characterized in that the lower end of the inner wall of the mold is formed into a tapered shape.