JPH0134706B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting core mold coating method and apparatus.

During the casting process, when molten metal is poured into a mold (main mold, core), the higher the temperature of the molten metal and the lower the refractory properties of the casting and sand, the rougher the surface of the mold becomes. Therefore, in order to improve the casting surface and improve sand removal to prevent burning, an aqueous solution of a coating agent (heat-resistant coating agent such as zircon sand, silica powder, graphite powder, etc.) on the mold surface (hereinafter referred to as coating material) The process involves applying a liquid (referred to as a liquid).

The conventional mold coating method is a so-called spray coating method, in which the mold coating solution is stirred in a pressure vessel and sent out using air pressure, and is applied to the mold surface in the form of a spray through the nozzle of a spray gun.

However, in this conventional method, the following various problems have arisen, particularly in the case of a core whose outer surface is coated.

(1) The mold coating liquid becomes atomized and scatters around the worker, creating a poor working environment.

(2) Since nearly 70% of the mold coating liquid does not adhere to the core surface and is absorbed by the dust collector or released into the atmosphere, there is also a large economic loss.

(3) If the core surface has many irregularities and a complex shape, a blind spot will occur for the spray, making it difficult for the coating liquid to adhere to the core, which may cause burning after casting.

(4) This causes unevenness in the coating and a large amount of coating solution adheres locally, which causes lumps (spherical solids) to form when the coating solution drips in those areas and dries, which makes it difficult to finish in the subsequent process. Is required.

The present invention was made in order to solve these conventional problems, and by using a method using dobu-zuke, the working environment can be improved, the mold can be coated well, and it is cost effective and work efficiency is improved. The object of the present invention is to provide a casting core mold coating method and apparatus that have various advantages such as excellent properties.

The present invention will be explained in detail below based on illustrated embodiments.

In FIGS. 1A to 1C showing one embodiment, a mold coating device according to the present invention is constructed as follows. An L-shaped arm 3 is rotatably supported at the upper end of a base 2 fixed on a support stand 1 via an arm rotation shaft 4.

A table rotation motor 5 is installed at the tip of the arm 3.
A table 7 fixed to a rotating shaft connected to the rotating shaft of the motor 5 via a gear train 6 is normally connected to a core conveyor 8 as shown by the solid line.
The upper surfaces of a pair of roller groups 9A and 9B, which are positioned in the gap between A and 8B and lined up in the core conveyance direction of the table 7, are set at the same height as the upper surfaces of the conveyors 8A and 8B.

The table 7 also has the pair of roller groups 9A,
Guide brackets 10A and 10B are provided that protrude upward from the outside of the central part of table 9B, and support shafts 11A and 11A are provided on both sides in the core conveyance direction, sandwiching the rotating shaft of table 7.
11B, and are symmetrically fixed to these support shafts 11A and 11B.
A, 12B to the support shafts 11A, 11B respectively, lever 1
Hydraulic cylinder 14 connected via 3A, 13B
A, 14B, it is normally stored below the roller groups 9A, 9B. The clampers 12A, 12B are rotated in opposite directions and erected by the extension strokes of the hydraulic cylinders 14A, 14B, respectively, and hard cushion rubbers 15A, 1 are fixed to their opposing surfaces.
The core can be elastically gripped between 5B.

One end of the arm rotation shaft 4 is connected to the drive shaft of an arm rotation motor 17 via a gear train 16, and by rotating the motor 17 in forward and reverse directions, the arm 3 is rotated 180 degrees from the solid line position. It is possible to switch to the position indicated by the chain line.

On the other hand, the floor surface 1 below the chain line position side of the arm 3
8 is formed lower than the support base 1 in a stepped manner, and a soaking tank 20 is installed on the floor surface 18 via a lifter 19 driven by a hydraulic motor (not shown). The dipping tank 20 filled with mold coating liquid up to the liquid level A can be moved up and down from the position shown by the solid line to the position shown by the chain line by driving the lifter 19.

In addition, in order to prevent the coating liquid from scattering when the core 21 is rotated and the excess coating liquid is shaken off by centrifugal force, as will be described later, when the core 21 is suspended vertically downward in the chain line position shown in the figure. A drum-shaped coating liquid scattering prevention cover 22 is provided to cover the periphery of the core while avoiding interference at the position of the dashed line in the soaking tank 20. The mold coating liquid scattering prevention cover 22 may be attached by fixing the lower end to the floor surface 18, the support stand 1, or the base 2, or by fixing the upper end to the arm 3 so that it can be attached and detached freely, but if there is enough space in the vertical direction. If there is (more room can be provided by lowering the hanging position from the arm 3), it may be fixed to the upper end of the gutter soaking tank 20 or formed integrally with the gutter soaking tank 20, in which case it may be separated. The excess mold coating liquid adheres to the inner wall of the cover 22 to prevent it from scattering to the surroundings, and then flows down and returns to the inside of the soaking tank 20, so there is no waste.

Next, a mold coating method using such a mold coating device will be explained.

For example, in the case of cores for casting engine cylinder blocks, crank cores, end cores, and center cores fired in a shell machine are assembled on a wooden surface plate, pasted together with adhesive, and then glued. To fix it, it is strung with a rubber band, and after about 30 minutes, it is placed on the conveyor 8A and conveyed toward the table 7.

In the mold coating device, before transporting the core, the hydraulic cylinder 14A is stroked in advance to rotate and raise the first clamper 12A on the advancing side in the transport direction, and at the same time, the soaking tank 20 is set at the position shown by the solid line in the figure.

In this state, the core 21 is transferred to the table 7, and its both ends are connected to a pair of guide brackets 10.
A and 10B are sandwiched and pushed in, and the distal end surface is brought into contact with the cushion rubber 15A of the first clamper 12A to position it.

Next, the second clamper 12B is connected to the hydraulic cylinder 1.
Rotate and raise the cushion rubber 15A of both clampers 12A, 12B by the stroke of 4B,
The core 21 is held elastically between the 15B and 15B.

In this way, the arm 3 holding the core 21 is rotated 180 degrees by the drive of the motor 17 and set at the position shown in chain lines.

After the setting, the soaking tank 20 located at the solid line position is raised by driving the lifter 19, and the clamper 1 is moved up.
The core 21 suspended and held by 2A and 12B is immersed in the mold coating liquid in the dipping tank 20. At this time, the mold coating liquid in the drip soaking tank 20 is held at liquid level A by the overflow mechanism, so that the core 21 can be molded only at a predetermined portion excluding the upper end in this state, and the inside of the core 21 can be coated. Since the mold liquid does not penetrate, wasteful consumption of mold coating liquid can be prevented.

Next, the motor 17 is reversed and the lifter 1
After lowering the dipping tank 20 together with 9 and exposing the core 21 to which the mold coating liquid has adhered to the air for several seconds, the dipping tank 20 is raised again to immerse the core 21.

Next, with the soaking tank 20 lowered and the core 21 exposed to the air, the table rotation motor 5 is driven to rotate the core 21 together with the table 7, and the centrifugal force generated at this time The excess coating liquid adhering to the surface of the core 21 is shaken off and separated.
The separated surplus coating liquid adheres to the inner wall of the coating liquid scattering prevention cover 22 and can be prevented from scattering to the surroundings.

When the mold coating work is finished, the motor 17 is reversed to rotate the arm 3 back to the conveyor 8A, 8B side, and then the pair of clampers 12A, 12
After rotating the core 21 back to the horizontal position and releasing the grip on the core 21, the core 21 is transferred to the conveyor 8B on the opposite side.
All you have to do is have it transported.

According to this mold coating method, conventional problems can be solved and various advantages are provided as described below.

(1) Unlike the spray method, it is possible to prevent the coating liquid from becoming atomized and floating in the air, which improves the working environment and work efficiency, and reduces wasteful consumption of the coating liquid, reducing costs. It's advantageous.

(2) There is no remaining coating liquid.

(3) Since the mold coating liquid penetrates well between the sand grains of the core by dipping, the concentration of the mold coating liquid can be lower than in the spray method, and it is possible to better suppress burning.

(4) Since centrifugation is performed after dipping, the coating liquid adheres uniformly to the surface of the core, and there are no lumps, eliminating the need for post-process finishing and suppressing the occurrence of burrs after casting. .

In addition, if the dip dipping is performed twice as in this example, there is an advantage that the coating liquid will adhere well to the surface even if the core has a complex shape with unevenness. However, the present invention does not limit the number of times of soaking. Furthermore, since the clamper is provided with a cushion rubber, damage to the core during clamping can be suppressed.

FIG. 2 shows a second embodiment of the invention. In this device, an arm 36 equipped with a core gripping mechanism 34 and a rotary table 35 similar to the embodiment described above is fixed to a wide chain 33 that is hung between a pair of upper and lower gears 31, 32. The core 3 is attached to the arm 36 which moves together with the chain 33 by the drive rotation of the
7 is immersed in a soaking tank 38 in a suspended state.
The subsequent steps are the same as in the previous example.

Reference numeral 39 denotes a coating liquid scattering prevention cover, which is attached to cover the periphery of the core 37 together with the chain 33.

As explained above, according to the present invention, the casting core is suspended and immersed in the coating liquid, and then rotated in the air, and the excess coating liquid is shaken off and removed by the centrifugal force. This not only improves the working environment, but also allows for good coating.
It has various advantages such as excellent cost efficiency and work efficiency.

[Brief explanation of drawings]

FIG. 1A is a front view showing one embodiment of the present invention, FIG. 1B is a plan view of the same embodiment, and FIG. 1C is A of FIG.
-A sectional view, FIG. 2 is a schematic configuration diagram showing a second embodiment of the present invention. 3... Arm, 5... Table rotation motor, 6...
Gear train, 7...Table, 12A, 12B...
Clamper, 16... Gear train, 17... Arm rotation motor, 19... Lifter, 20... Dip soaking tank, 2
1... Core, 22, 39... Coating liquid scattering prevention cover,
31, 32... Gear, 33... Chain, 34... Core gripping mechanism, 35... Rotary table, 36... Arm, 37... Core.

Claims (1)

[Scope of Claims] 1. After the casting core is immersed in the coating liquid, it is exposed to air and rotated, and the excess of the coating liquid adhering to the core surface is shaken off by centrifugal force and divided. A casting core coating method characterized by: 2. With the casting core fixedly gripped on the rotary drive shaft attached to the arm, the arm is rotated 180 degrees in the vertical plane to create a core gripping device that can be hung vertically downwards, and when the molding liquid is filled, A drain soaking tank is installed to be able to move vertically relative to the core suspended from the gripping device, and the core gripping device and the drain soaking tank are brought close to each other in the vertical direction to drain the core. After soaking, the core is vertically separated and the core is exposed to the air, and the rotary drive shaft is rotated to rotate the core, and the core is further provided with a coating liquid scattering prevention cover that surrounds the rotating core. A casting mold coating device for casting cores.