JP2007098433A - Device for screening molding sand - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for screening molding sand, which device can reduce a floor space therefor, and also can reduce equipment cost. <P>SOLUTION: The screening apparatus for carrying out the screening of the returned recovery sand produced by the shake-out of the mold in order to collect the recondition-able molding sand comprises: a first rotary drum type screening device for screening the returned recovery sand with a coarse-meshed sieve; a belt conveyer for carrying the returned recovery sand screened by the first rotary drum type screening device; a second rotary drum type screening device partitioned into an upstream portion for rotationally cooling the returned recovery sand screened by the first rotary drum type screening device and a downstream portion for further screening the cooled returned recovery sand; and a vibratory screening device, which is arranged just below the second rotary drum type screening device, and carries out the further fine-meshed screening of the returned recovery sand screened by the second rotary drum type screening device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a molding sand sieving apparatus. More specifically, the present invention relates to a molding sand sieving treatment apparatus that can reduce the installation space, reduce the equipment cost, and improve the quality of the reclaimed molding sand.

  Conventionally, in a sand circulation casting facility, a mold after pouring is separated by a vibrating conveyor or a rotating drum type separation device, and then separated into mold sand (spread sand) and a cast product. After the sand is collected, it is recycled to mold sand that can be reused by sieving. As a method for treating the mold sand, the recovered mold sand in a high temperature state separated from the cast product is roughly sieved to remove the lump of the mold sand, and then cooled to a temperature of about + 5 ° C. with a sand cooler. There is a method of reducing the size and then applying to a fine sieve (a wire mesh with an opening of 5 × 25 mm) and an ultrafine sieve (a wire mesh with an opening of 0.5 to 0.6 × 2.5 to 3.0 mm) in order. (See Patent Document 1). This method cools the mold sand with a sand cooler and at the same time reduces the water content, so that it can regenerate fine sand without clogging when it is put on a fine or ultra-fine sieve. .

JP 59-229255 A

  However, in the method described in Patent Document 1, a hopper and a belt feeder are used for transporting the recovered mold sand between the rough sieve, the sand cooler, the fine sieve and the ultrafine sieve, respectively. For this reason, there are problems that the number of hoppers and belt feeders is increased, the installation space for the sieving processing device is increased, and the equipment cost is increased.

  Therefore, in view of the above circumstances, an object of the present invention is to provide a molding sand sieving apparatus that can reduce the installation space and reduce the equipment cost.

  The mold sand sieving apparatus according to the present invention is a mold sand sieving apparatus for sieving returned recovered sand generated by mold separation into a reusable mold sand, and applies the returned recovered sand to a rough sieve. A first rotating drum type sieving device, a belt conveyor for transporting the return recovered sand sieved by the first rotating drum type sieving device, and a sieve by the first rotating drum type sieving device. A second rotary drum type sieving device that is divided into an upstream part for rotationally cooling the return recovered sand and a downstream part for further sieving the returned recovered sand after cooling; and immediately below the second rotary drum type sieving device. Vibrating sieving device that is arranged and further finely screens the return recovered sand that has been sieved by the second rotating drum type sieving device It is characterized in that it comprises a.

  According to the present invention, since there are few belt conveyors used for transporting the return-recovered sand placed on the sieve, it is possible to reduce the installation space for the sieving treatment apparatus and reduce the equipment cost.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mold sand sieving apparatus according to the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, a mold sand sieving apparatus according to an embodiment of the present invention generates a mold after pouring by mold separation by a vibrating conveyor or a rotary drum type separation device (not shown). Belt conveyor 1 for transporting the return mold sand and return collected sand S1 including core sand, a first rotary drum type sieving device 2 disposed behind the belt conveyor 1, and the first rotation Immediately below the drum-type sieving device 2, a belt conveyor 3 that conveys the return recovered sand S <b> 2 that has been roughly screened by the first rotary drum-type sieving device 2, and a second conveyor disposed behind the belt conveyor 3. The rotary drum type sieving device 4 and the vibration type sieving device 5 disposed immediately below the second rotary drum type sieving device 4 are provided. Further, in the present embodiment, a large iron piece is removed from the return collection sand S1 conveyed by a magnet separator (not shown) suspended above the belt conveyor 1, and a small iron of 3 mm or less. The balls are separated and removed by magnetizing the drive pulley 1a of the belt conveyor 1. Note that reference numeral 6 in FIG. 1 denotes an iron ball discharge chute. The reclaimable mold sand treated according to the present embodiment is conveyed to a kneader and then kneaded with water and a binder. The kneaded sand is used for mold making by a mold making machine.

  The first rotary drum type sieving device 2 is a device for placing the separated return collected sand S1 on a rough sieve, and a main body 7 and a rotary shaft (supported by a bearing portion 8 for rotation on the main body 7). A sieve 9 having a cylindrical shape that is long in the left-right direction (left-right direction in FIG. 1), for example, having an opening of about 21 mm, and a drive motor mechanism (not shown) for rotationally driving the sieve 9 And a supply chute 10 that supplies the recovered sand S1 to the sieve 9 and a discharge chute 11 that discharges 21 mm or more of sand lumps and core waste while collapsing the return recovered sand S1 by the impact caused by dropping. And a storage tank 12 for temporarily storing the return recovered sand S2 screened under the main body 7 and discharging it to the belt conveyor 3 as appropriate.

  The second rotary drum type sieving device 4 is a device for further sieving the return recovered sand S2 applied to the sieve by the first rotary drum type sieving device 2, and the return recovered sand applied to the sieve. A main body 23 divided into an upstream portion 21 for rotating and cooling S2 and a downstream portion 22 for sieving the returned recovered sand S2 after cooling, and a supply for supplying the recovered sand S2 to the upstream portion 21 in the main body 23 A chute 24, a discharge chute 25 for discharging sand lumps and cores of 5 to 20 mm from the downstream portion 22 in the main body 23, and the return collected sand screened directly under the main body 23 are temporarily stored and appropriately And a storage tank 26 for discharging to the vibration screening device 5. In the present invention, the internal structure of the main body 23 is not particularly limited as long as it is partitioned into an upstream portion 21 and a downstream portion 22. For example, the upstream portion 21 has a stirring plate attached to the drum inner surface. The agitating plate scoops up the collected sand in the drum to increase the efficiency of crushing and cooling. The downstream portion 22 has a sieve structure with an opening of 5 × 25 mm (wire diameter φ2.5 mm), and discharges more than the sieve. The return collected sand in the upstream portion 21 is cooled while being repeatedly collapsed due to an impact caused by falling while being rotated. For this reason, this upstream part 21 functions as a cooling part.

  The vibratory sieving device 5 is a device for further finely sieving the return collected sand S3, which has been passed through the second rotating drum type sieving device 4, and is supported on a base 31 by a coil spring 32. A filter funnel 33 having a filter funnel, a vibration motor 34 for applying vibration to the vibration container 33, a sieve 35 having an opening of about 3 mm extending horizontally in the vibration container 33, and sand having a thickness of 3 to 5 mm And a discharge chute 36 for discharging lumps and core waste. The base 31 is provided with a collection path 37 for collecting fine sand of 3 mm or less dropped from the sieve 35.

  In the present embodiment, the upstream portion 21 that is the first half of the second rotary drum type sieving device 4 functions as a cooling portion, and the downstream portion 22 that is the second half is used as a sieving portion with an opening of 5 mm with good sieving efficiency. Since it is functioning, cooling and efficient fine sieving can be performed in a small space. Further, since the sieving is performed by the vibration type sieving device 5 having an opening of 3 mm, further fine sieving is possible. Thereby, in this Embodiment, while an installation space is small, an installation cost can be reduced, and return return sand can be efficiently processed into recyclable casting sand.

It is a schematic block diagram of the mold sand sieving processing apparatus concerning one embodiment of the present invention.

Explanation of symbols

1, 3 Belt conveyor 1a Drive pulley 2 First rotating drum type sieving device 4 Second rotating drum type sieving device 5 Vibrating sieving devices 6, 11,
25, 36 Discharge chute 7, 23 Main body 8 Bearing part 9, 35 Sieve 10, 24 Supply chute 12, 26 Storage tank 21 Upstream part 22 Downstream part 31 Base 32 Coil spring 33 Vibration container 34 Vibration motor

Claims (2)

A mold sand sieving treatment apparatus for sieving the return recovered sand generated by mold separation into a reusable mold sand,
A first rotating drum type sieving device for passing the return recovered sand over a rough sieve;
A belt conveyor for transporting the recovered sand collected by the first rotating drum type sieving device;
The second rotary drum type sieving is divided into an upstream part for rotating and cooling the return recovered sand applied to the sieve by the first rotary drum type sieving device and a downstream part for further passing the recovered return sand after cooling to the sieve. Equipment,
And a vibration type sieving device that is arranged directly below the second rotating drum type sieving device and further finely sifts the recovered sand collected by the second rotating drum type sieving device. A molding sand screening device. 2. The molding sand sieving apparatus according to claim 1, wherein an opening of a downstream portion of the second rotary drum type sieving apparatus is about 5 mm.