JPS60213336A - Molding of self-curing casting mold - Google Patents

Abstract

PURPOSE:To simplify a device without the need for an intricately constructed blow head and large-sized clamping device by packing the sand in hoppers into a casting mold box or molding flask by a suction system. CONSTITUTION:The sands in hoppers 32, 43 are respectively supplied into mixing tanks 24, 35 and further stop valves 34, 45 are opened to supply a binder and hardener into the tanks 24, 35. The sand mixed with the binder and the sand mixed with the hardener are mixed with each other by impellers 23 and are then stored in a hopper 15. A stop valve 12 is then opened to suck and evacuate the inside of hollow chambers 6, 7 and a cavity 5 and thereafter a sliding gate 16 is moved by a cylinder 19 to open the bottom end of the hopper 15. The sand in the hopper 15 is sucked and packed into the cavity 5. The gate 16 is then reset by a cylinder 19 and the suction effect into the chambers 6, 7 is stopped by closing the bottom end port of the hopper 15 and closing the valve 12. This state is maintained until the packed sand is hardened. A movable mold 4 is moved leftward by a cylinder 3 upon curing of the sand and the desired casting mold is thus obtd.

Description

[Detailed description of the invention] The present invention relates to a method for making a self-hardening mold.

Conventionally, sand mixed with binders and hardeners for making hard molds is generally filled into a mold box by a blowing method using compressed air. Problems include the need for a blow head with a complicated structure, as well as the need for a large clamping device to clamp the mold box with a large force to prevent sand from blowing out.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a self-hardening mold that does not require a complicated blow head or a large clamp device.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. (1) is a vertically split mold box, which is composed of a fixed mold (2) and a movable mold (4) that is moved by a horizontal cylinder (3). A cavity (5) having a baseboard part (5a) which also serves as a sand suction hole is provided in the mold box (1), and a hollow chamber (5) is provided at the back of the fixed mold (2) and the movable mold (4). 6), (7) are formed, and the fixed type (2),
The cavity surface of the movable type (4) has vent holes (8), (
9) to the hollow chambers (6) and (7), respectively. In addition, the hollow chambers (6) and (7) are provided with flexible conduits (
10), is connected to a vacuum pump (14) via a conduit (11), an on-off valve (12), and a vacuum reservoir tank (13). (15) is a funnel-shaped hopper that is movable up and down directly above the closed mold box (1), and a slide gate (16) and an intermediary member (17) are attached to the lower end of the hopper (15). The slide gate (16) is moved from side to side by the expansion and contraction of a horizontal cylinder (19) fixed to the hopper (15) via a bracket (18). (20) is a vertical cylindrical kneading tank with an open bottom, and a vertical rotating shaft (22) rotated by a downward motor (21) is disposed inside the kneading tank (20). A plurality of mixing blades (23) are mounted on the rotating shaft (22).
) is installed. (24) is a kneading tank which has a horizontal cylindrical shape and has both openings closed. Inside the kneading tank (24), there is a horizontal motor (25) fixedly installed on the side plate of the kneading tank (24). ) rotates the horizontal rotating shaft (
26) is disposed with the other end supported by the side plate of the mixing tank (24), and a plurality of mixing blades (27) are disposed on the rotating shaft (26).
is installed. A supply port (28) is located at the upper left end of the kneading tank (24), and a discharge port (28) is located at the lower right end.
9), the supply port (28) is equipped with a slide game (31) operated by a cylinder (30) and a hopper (32), and the discharge port (29) is connected to the kneading tank (20). It's coming. In addition, a conduit (33) and an on-off valve (34) are located near the supply port (28) of the kneading tank (24).
) A pump (not shown) and a self-hardening mold-making binder storage tank are connected in communication. (35) is a kneading tank having the same form as the kneading tank (24), and a horizontal rotating shaft (37) rotated by a motor (36) is provided in the kneading tank (35). 37) is also attached with a plurality of crosstalk vanes (38).

There is a supply port (39) at the upper right end of the kneading tank (35).
However, a discharge port (4o) is formed at the lower left end, and the supply port (39) also has a slide gate (42) and a hopper (43) operated by the cylinder (41) in the same way as the supply port (28). is installed, and the discharge port (4o) also faces the kneading tank (2o). Further, near the supply port (39) of the kneading tank (35), a conduit (44) and an on-off valve (
45), a pump (not shown) and a hardening agent storage tank for self-hardening mold making are connected in communication.

Next, the operation of the device configured as described above will be explained. The motors (21), (25), (36) are driven to rotate the rotating shafts (22), (26), (37) and the kneading blades (23).
), (27), and (38) are rotated, the cylinders (30) and (41) are extended, and after a predetermined time, they are contracted to reciprocate the slide gates (31) and (42), The sand in the hoppers (32) and (43) is mixed in the tank (24)
, (35), and then open the on-off valves (34) and (45) and after a predetermined period of time have elapsed, predetermined amounts of binder and curing agent are added to the kneading tanks (24) and (35). As a result, the sand to which a binder has been added is kneaded in the kneading tank (24), and the sand to which a hardening agent has been added is kneaded in the kneading tank (35). Then, the amount of sand corresponding to the volume of the cavity (5) is put into the discharge port (29) (40).Then, the binder-mixed sand and the hardener-mixed sand are mixed by the kneading blade (23) and then transferred to the hopper. (15).Next, open the on-off valve (12) to suction and reduce the pressure inside the hollow chambers (6), (7) and the cavity (5), and then extend the cylinder (19) to reduce the pressure in the slide gate (16). ) to move the hopper (
When the lower end opening of 15) is opened, the sand in the hopper (15) is sucked into the cavity (5) and filled. After sand filling is completed, the cylinder (19) is contracted to return the slide gate (16) to close the lower end opening of the hopper (15), and then close the on-off valve (12) to close the hollow chamber (6).
7) Stop the suction action and maintain that state until the filling sand hardens. After the filling sand in the cavity (5) hardens, the cylinder (3) is contracted to move the movable mold (4) to the left to obtain a desired mold. Next, the cylinder (3) is extended to move the movable mold (4) to the right,
Thereafter, by repeating the above operations, the mold can be intermittently formed.

In addition, if the viscosity of the binder and hardener is low, the binder and hardener may be added to the sand at the same time and kneaded, or they may be kneaded directly in the hopper (15). It's okay. Further, the sand in the hopper (15) may be sucked and filled into a flask equipped with suction and pressure reducing means.

As is clear from the above description, the present invention uses a suction method to fill the sand in the hopper into the mold box or flask, which eliminates sand blow-outs and provides a large clamp for clamping the mold box, etc. It has excellent effects such as eliminating the need for devices and blow heads with complicated structures.

[Brief explanation of the drawing]

The drawing is a front view, partially cut away, of an apparatus used to carry out the invention. (1): Mold box (13): Vacuum cash register I tank (15): Hopper procedure manual (method) 1. Indication of the incident 1980 Patent application No. 69534 2. Name of the invention Self-hardening Mold molding method 3, relationship with the amendment case Patent applicant address (residence) 4-7-2 Meieki, Nakamura-ku, Nagoya, Aichi Prefecture
No. 3 Shinto Kogyo in the Toyota Building Name (Name) Shinto Kogyo Co., Ltd. July 11, 1980 (Delivery date: July 31, 1988) 5. Subject of amendment ``Brief explanation of the drawings in the specification'' Column J and “Drawing 1゜6,
Contents of correction

Claims (1)

[Claims] A predetermined amount of sand mixed with a binder and a hardening agent for self-hardening mold making is stored in a hopper, the entire amount of sand in the hopper is filled into a mold box or flask by suction, and the filled sand is A method for making a self-hardening mold, which comprises maintaining the condition until the sand is hardened, and then taking out the hardened sand from the mold box or flask.