JPH10113744A - System for kneading and supplying molding sand - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain always stable moldability by charging kneading-adjusted molding sand into a sand storage after breaking up the lump sand contained in the molding sand. SOLUTION: The molding sand containing the lump sand developed during kneading is charged into a lump sand breaking-up machine. In the lump sand breaking-up machine, since a dispersing cap 6e and dispersing blades 6f are rotated by rotating a shaft 6d, the molding sand is instantly dispersed in every direction in a case 6b. The dispersed molding sand is sprung out with comparatively high speed rotating force of rotating pins 6g and hit against an impingement plates 6j while colliding to fixed pins 6i or directly hit against the impingement plates 6j and so, the lump sand is sufficiently broken up and dropped and stored into the sand storage through an opening part. Therefore, since the molding sand is immediately stored after breaking up the lump sand, the chance of the vaporization of moisture becomes few and the variable range of the moisture and CB (contactability) can be small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adjusting and conveying molding sand by adding an additive such as bentonite to sand and kneading the mixture. The present invention relates to a series of systems to be put into a molding flask.

[0002]

2. Description of the Related Art To prepare molding sand for mold molding, bentonite and the like are added to the sand and kneaded to adjust the molding sand. The molding sand obtained by kneading is subjected to molding, casting, and post-processing. Considering that a series of subsequent steps is constituted, it is necessary to prepare a casting flask at a place which is considerably away from the installation position of the kneading machine, and to inject molding sand into the casting flask. During this kneading, some of the foundry sands are combined with sand grains by kneading to form agglomerates. However, in order to obtain a good mold, it is necessary to loosen this finely and put it into a casting flask. For this reason, conventionally, the kneaded molding sand is once taken out, transferred to a lump loosening machine such as a sand blender, and the lump is sufficiently loosened before being transported on a belt conveyor.

[0003]

However, in such a method, there is a possibility that the moisture in the molding sand is evaporated and lost when the lump is loosened, and the finely divided casting in a state where the lump is loosened. Since the sand needs to be transported a considerable distance before it is finally put into the mold, the molding sand is liable to evaporate and be lost due to prolonged contact with air. There has been a problem that the fluctuation range of the amount of water in the casting sand increases and the fluctuation range of the CB (contactor tie) value also increases, resulting in unstable moldability. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a kneading and feeding system for molding sand that can always obtain stable moldability.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a molding sand kneading and feeding system according to the present invention comprises a kneading-adjusted molding sand which is conveyed by a belt conveyor and is located at a distance from the kneading machine. When pouring into the installed sand storage, the lump in the molding sand is loosened with a lump loosening machine provided in communication with the inside of the sand storage at the upper part of the sand storage, and then the sand is removed. Put it into the storage. As a result, the evaporation of the moisture in the molding sand can be suppressed as much as possible, and the fluctuation range of the moisture and the CB value in the molding sand can be reduced.

[0005]

An embodiment of the present invention will be described with reference to the drawings. A hopper 2 for receiving the kneaded and adjusted molding sand is provided directly below the kneading machine 1 for adjusting molding sand.
Below the hopper 2, there is provided a belt feeder 3 for conveying the foundry sand cut out from the hopper 2. At the end of the belt feeder 3, a first transfer sheet 5 for transferring molding sand onto a belt conveyor 4 running below is provided.

[0006] The belt conveyor 4 is installed with a gentle inclination, and at the end thereof, a second transfer shoe 7 for transferring casting sand into the lump loosening machine 6 is provided. The lump loosening machine 6 is a sand storage.
The upper part of the jig 8 is fixedly connected to the inside of the sand storage 8 so as to have a structure as shown in FIG.

That is, the case 6b fixed on the base 6a
A receiving hopper 6c is formed at the upper center of the hopper. A conical dispersion cap 6e is rotatably fitted to the upper end of a rotating shaft 6d connected to a motor (not shown) at the center of the box 6b, and is closely attached to the bottom surface of the dispersion cap 6e. Dispersion blade 6 having a right-handed spiral shape when viewed from above
f are fitted to the rotary shaft 6d. A rotating plate 6h is detachably fitted to a rotating shaft 6d slightly below the dispersion blades 6f, and a large number of rotating pins 6g are arranged at regular intervals around the outer edge of the rotating plate 6h in the circumferential direction. It is fastened upright.

On the case 6b near the outer periphery of the receiving hopper 6c, a large number of fixed pins 6i are located outside the rotary pins 6g and are arranged at regular intervals in the circumferential direction. Has been established. The number of the fixing pins 6i is slightly smaller than the number of the rotating pins 6g.
Further, the molding sand injected by suspending the collision plate 6j in the box 6b outside the fixing pin 6i collides with the collision plate 6j, and does not scatter outside the collision plate 6j. It has been like that. In addition, the molding sand from which the lumps are loosened by colliding with the collision plate 6j is removed from the gantry 6a.
And is inserted into the sand storage 8 through an opening (not shown) communicating with the sand storage 8 in a vertical direction. At the bottom of the sand storage 8, there is provided a second belt feeder 9 for introducing molding sand cut out from the sand storage 8 into the casting flask 10, and the casting flask 10 is provided with the second belt feeder 9. It is provided at a lower front position of the two-belt feeder 9.

A series of procedures for adjusting the molding sand in the kneading and supplying system for molding sand thus configured and finally putting it into the casting flask will be described. First, an additive such as bentonite is added to silica sand and kneaded in the kneading machine 1 to prepare molding sand.
The molding sand that has been sufficiently kneaded and adjusted is discharged from the kneading machine 1 and put into the hopper 2. The casting sand introduced into the hopper 2 is cut out by the belt feeder 3 in a predetermined amount, transferred onto the belt conveyor 4 via the first transfer sheet 5, and transferred onto the belt conveyor 4. It is conveyed and put into the lump loosening machine 6 via the second transfer shoe 7.

During this time, the molding sand is not subjected to any treatment after kneading, so that the lump generated during kneading is fed into the lump unraveling machine 6 without being loosened. Therefore, since the foundry sand is sent without being subjected to the sand loosening action, the moisture is hardly evaporated and is transported to the position of the lump loosening machine 6. The lump of the foundry sand is loosened as follows. That is, the dispersion cap 6e and the dispersion blade 6 in the lump loosening machine 6
Since f is rotated by the rotation of the rotary shaft 6d, the molding sand is instantaneously dispersed in four directions in the case 6b.

The dispersed foundry sand is repelled by the rotating pin 6g which is rotating at a relatively high speed and hits the collision plate 6j while colliding with the fixed pin 6i, or directly. By hitting the jig 6j, the lumps are sufficiently crushed, fall, and are stored in the sand storage 8 through the opening. Therefore, the foundry sand is stored immediately after the lump loosening, so that the chance of water evaporation is reduced and the evaporation is minimized. The stored foundry sand is transferred to the second belt filter.
It is put into the casting flask 10 through a die 9.

As is apparent from the above description, the present invention transfers the kneaded and adjusted molding sand onto a belt conveyor, conveys the sand, and supplies the sand into a sand storage disposed near the casting flask. A molding sand kneading and feeding system for gradually cutting out the foundry sand and putting it into the casting flask, wherein the foundry sand dropped and discharged at the end of the belt conveyor is dispersed laterally by rotating dispersing blades. A plurality of rotating pins for rotating the outer periphery of the dispersing blade, a fixed pin disposed on the outer periphery of the rotating pin, and a damper disentangler for hitting a collision plate provided on the outer periphery of the fixed pin. Then, since the water is supplied to the sand storage by dropping, the evaporation of the water in the molding sand is minimized without reducing the degree of loosening of the lump, and the fluctuation range of the water and the CB value in the molding sand is reduced. Illusion it is possible to obtain a stable molding properties.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram of a kneading and feeding system for foundry sand in the present invention.

FIG. 2 is a longitudinal sectional view of a main part of a lump loosening machine used in the present invention.

[Explanation of symbols]

 Reference Signs List 4 belt conveyor 6 lump unraveling machine 6f dispersing blade 6g rotating pin 6i fixing pin 6j collision plate 7 second transfer shoe 8 sand storage

Claims (1)

[Claims] The sand sand is provided in the vicinity of a casting frame by transferring the kneaded and adjusted molding sand onto a belt conveyor.
A kneading and feeding system for molding sand, which is supplied into the jig, gradually cuts out the supplied molding sand, and puts the molding sand into the casting frame, wherein the molding sand dropped and discharged at the end of the belt conveyor 4 is rotated and dispersed. A plurality of rotating pins 6 that are laterally dispersed by the blades 6f and rotate around the periphery of the distributed blades 6f.
g, and a fixed pin 6 disposed on the outer periphery of the rotating pin 6g.
i, and a collision plate 6 provided on the outer periphery of the fixed pin 6i.
j. A kneading and feeding system for molding sand, wherein the jig is loosened by a damper unraveling machine 6 and dropped and supplied to the sand storage 8.