JPS6321952Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The invention is based on a trough configured to supply mold-forming sand and its binder, and a blade with a large stirring surface on the tip side installed on a rotating shaft. The mold-forming sand and binder are mixed and transferred by the rotation of stirring blades, and at the same time, the sand and binder are mixed and transferred by the rotation of the stirring blade, and a mixture is placed at the outlet portion of the mixture formed in the trough at the end of the transfer path, which crosses the mixture discharge flow path. The present invention relates to a continuous sand mixer equipped with an opening/closing device consisting of a plate-shaped body that moves in a direction and an operating tool for the plate-shaped body.

[Conventional technology]

If a mixer is used, a mixture of sand and binder can be obtained continuously and molds can be made efficiently, but at the start of operation, the timing of supplying the sand and binder tends to lag in time. Due to the unbalance in the supply amount, the properties of a certain amount of the mixture at the beginning of the operation were far from the expected ones, and the mixture was wasted.

In particular, when the mixer is repeatedly stopped each time a mold is made, a large amount of the mixture is wasted, which is uneconomical.

For example, the conventional technology proposed in Japanese Utility Model Publication No. 45-27052, as a means to solve this problem,
An opening/closing device was provided at the mixture outlet of the straight trough. This is done by keeping the outlet closed at the beginning and only opening it once the trough has been filled with some sand or binder, so that the first feed receives sufficient mixing with the following. It was homogenizing.

[Problem that the invention attempts to solve]

When mold-forming sand and binder are mixed using a conventional mixer equipped with an opening/closing device at the discharge port, the mixture is compacted near the discharge port because the discharge port is closed, causing the sand to flow. In addition to impairing the properties of the mixture, there was a problem in that once the mixture solidified, the stirring blade and the mixture would rotate together, making it impossible to achieve homogenization.

The present invention aims to provide a continuous casting sand mixer that does not impair the fluidity of casting sand while providing the above-mentioned homogenization effect by providing an opening/closing device.

[Means for solving problems]

The technical means of the present invention taken to solve the above problems is that in the continuous casting sand mixer explained in the industrial application field, the radius of the trough at the end portion in the sand transfer direction is adjusted to the entire circumference. In addition to being larger than the other parts, the rotating stirring blade in that part is also made to have a larger radius than the other part.

[Effect]

At the end of the transfer path, a large retention space that extends in the radial direction of the trough is formed, so the mixture that reaches the end moves in the radial direction of the trough and diffuses into this space. This provides sufficient stirring action.

[Effect of idea]

According to the above-mentioned technical means of the present invention, the above-mentioned action can prevent the compacting action based on the transfer force of the stirring blade, and the fluidity of the casting sand can be maintained. In other words, by creating a sufficiently large retention and stirring space that extends in the radial direction, a larger amount of the mixture can be remixed while maintaining fluidity than before, and the above-mentioned effect can be achieved. Homogenization can be made more complete, and the configuration for this purpose is extremely simple.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

A cylindrical trough 2 is attached to one end of the mixer frame 1 so as to be rotatable around the vertical axis.
Bearings 3 and 4 are provided to cover the openings at both ends of the trough 2, and a shaft 6 on which a large number of stirring blades 5 with large stirring surfaces are installed on the tip side is aligned with the longitudinal axis of the trough 2. It is constructed in the form of a core and spans both bearing parts 3 and 4. A supply port 7 for mold-forming sand and a binder thereto is formed in the upper part of one end of the trough 2 near the rotation axis, and a discharge port 8 for a mixture of sand and binder is formed in the lower part of the other end of the trough. At the same time, a hopper 9 facing the supply port 7 and a discharge pipe 11 equipped with an opening/closing device 10 facing the discharge port 8 are connected to the trough 2, and are arranged along the longitudinal direction of the trough 2. A bracket 12 is extended to one end of the trough 2, and a rotational drive device 15 consisting of a motor 13 and a speed reducer 14 is mounted on the bracket 12, and its reduction rotation shaft 14a and a bearing at one end of the trough are mounted. The stirring shaft 6 protruding from the part 3 is interlocked and connected by a coupling 16 to form a continuous casting sand mixer.

Among the rotary stirring blades 5 installed inside the trough 2, those provided in the range from the supply port 7 to the discharge port 8 stir and mix the sand and binder, and at the same time direct the mixture sequentially toward the discharge port 8. The blades 5, which are provided in an intermittent spiral shape as a whole and are provided near the discharge port 8, are provided so as to repeatedly stir the mixture staying in that part, and An overflow prevention plate 17 is provided hanging inside the trough near the supply port 7 and on the trough end side with respect to the group of blades 5 .

The opening/closing device 10 includes a plate-shaped body 18 that moves in a direction transverse to the mixture discharge channel of the discharge pipe 11;
It consists of an operating tool 19 for this, and is designed to allow any intermediate opening degree to be obtained between a fully open state and a fully closed state of the discharge flow path. This opening/closing device 1
0, by switching the discharge flow path to a fully closed state at the beginning of the operation when sand and binder are mixed, even if the supply timing of sand and binder is shifted and the supply amount becomes unbalanced, it is possible to maintain the balance between the sand and binder and the retention space described later. By working together, it can be sufficiently retained and agitated in the truck, and it can be mixed and agitated with the subsequent material supplied at a predetermined ratio, thereby homogenizing the entire retained mixture, thereby increasing the concentration of the mixture. The properties can be made close to the desired ones, and a mixture can be obtained continuously with almost no loss in the initial stage of operation.

Incidentally, an imbalance in the supply amount also occurs due to a difference in the timing of the supply stop when the operation is stopped, and in this case as well, the properties of the mixture can be improved by closing the flow path of the discharge port 8. However, in general, the mixture supplied to the mold before the operation is stopped is often in a state that has no relation to the casting surface, so there is no need to close the flow path, and the mixture is discharged by the opening/closing device 10. It is also possible to control the supply amount of the mixture by setting an intermediate opening degree of the flow path, and the opening/closing device 10 can be used properly as necessary.

The radius of the part of the sand transfer path in the trough 2 that is close to the discharge port 8 is made larger than the other parts around the entire circumference, and the radius of the rotary blades 5 provided in that part is also made larger accordingly to create a retention space. The temperature is increased to allow effective retention and stirring of the mixture.

The opening/closing device 10 may be manually operated or driven, but when driven, the opening/closing device 10 closes the discharge port 8 upon input of a command to start operation, and after that,
It is preferable to perform control such as a program to open the discharge port 8 after a certain set time has elapsed.

[Brief explanation of the drawing]

The drawing is an overall side view showing the continuous casting sand mixer of the present invention, with main parts broken. 2... Trough, 5... Stirring blade, 6... Rotating shaft, 8... Discharge port, 10... Switching device, 18...
Plate-shaped body, 19... operating tool.

Claims (1)

[Scope of utility model registration request] In a trough 2 configured to supply mold-forming sand and its binder, impellers 5 having a large stirring surface on the tip side are embedded in a rotating shaft 6, and the supplied mold-forming sand is and the binder are mixed and transferred by the rotation of the stirring blades 5, and a plate-shaped body 18 that moves in a direction transverse to the mixture discharge flow path is placed at the mixture discharge port 8 formed in the trough 2 at the end of the transfer path. , the operating tool 1 for the plate-shaped body 18
9, the radius of the trough 2 at the end portion in the sand transfer direction is formed larger than the other portions over the entire circumference, and rotational agitation is performed in that portion. In this continuous casting sand mixer, the blade 5 also has a larger radius than the others.