JPS637403Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a kneader for kneading foundry sand, particularly foundry sand for cold box molds. In the kneading machine, it is customary to leave a slight gap between the outer edge of the stirring blade (hereinafter referred to as scraper) and the inner wall of the kneading tank. By the way, molding sand for cold box molds has strong adhesion and hardens easily.In particular, sand that adheres in a layer in the gap between the bottom plate of the mixing tank and the lower edge of the scraper that scrapes up the sand on the bottom plate is , it absorbs the binder supplied in each batch and hardens significantly. Therefore, the lower edge of the scraper wears out in a short time due to contact with the adhered sand layer.
The sand cannot be kneaded sufficiently, and it takes a lot of time and effort to remove the adhering sand layer after the kneading operation.

In addition, in conventional homogeneous kneading machines, the scraper and the shaft that rotates it are fixed together, and only the top of the kneading tank can be opened.
When taking the scraper out of the machine for cleaning, remove the top cover, remove the kneading tank from the support,
This required work such as loosening the chuck holding the rotating shaft, which was very troublesome.

The present invention has been developed in view of the above-mentioned circumstances, and it is an object of the present invention to provide a kneading machine that prevents molding sand from adhering to the bottom plate and allows the scraper to be quickly and easily removed from the machine.

Hereinafter, the present invention will be explained in detail based on an embodiment. In Fig. 1, a rotating shaft 1 supported vertically
A motor pedestal 2 is fixed to the upper position, and a vertical cylindrical kneading tank 3 is fixed to the lower position.

A motor 4 is mounted on the motor stand 2;
A speed reducer (not shown) that can be interlocked with the speed reducer through a belt 5 and a vertical shaft 6 that can interlock with the speed reducer through gears are fixedly mounted, and the center line of the vertical shaft 6 and the kneading It is made to coincide with the center line of tank 3. The kneading tank 3 has an upper lid 7, a side plate 8 and a bottom plate 9.
The bottom plate 9 is vertically rotatable about a pin 10 and can be fastened to the kneading tank 3 with a bolt 11. A chuck 12 is attached to the lower end of the vertical shaft 6,
The chuck 12 grips a shaft 13 that passes through the upper lid 7 of the kneading tank 3 and reaches the bottom plate 9. As shown in FIG. 2, a cylindrical boss 14 is fitted to the lower end of the shaft 13 so as to be slidable up and down, and both are rotatable together via a key 15. The inner diameter of the portion of the boss 14 from approximately the middle to the upper end is larger than the outer diameter of the shaft 13, and the hollow portion defined by the large diameter portion and the outer peripheral surface of the shaft 13 has a The spring member 16 is connected to the shaft 13
It is arranged by wrapping it around. Additionally, four scraper mounting arms 17 are provided on the outer periphery of the lower end of the boss 14.
are fixed radially and at equal angles, and the arm 17 has a scraper 18 (hereinafter referred to as A scraper) for scraping up the sand on the bottom plate 9;
Two scrapers 19 (hereinafter referred to as B scrapers) for dropping floating sand downward are attached alternately. Note that the A scraper 1
The lower edge of the B scraper 19 is in contact with the upper surface of the bottom plate 9, and the B scraper 19 is arranged so that its outer edge has a slight gap between it and the side plate 8. . At a position a predetermined distance above the lower end of the shaft 13, a spring retainer 23 is mounted, which is made up of an annular member 21 that fits onto the shaft 13 and a cylindrical member 22 that is fixed to the outer periphery of the lower surface of the annular member 21. , the spring retainer 23 is attached to the spring member 16
is pressed with a predetermined pressure. The inner diameter of the cylindrical member 22 is slightly larger than the outer diameter of the boss 14, so that the boss 14 and the spring retainer 23 can be fitted loosely.

In the kneading machine configured as described above, when sand and binder are put into the kneading tank 3 and the motor 4 is driven, the vertical shaft 6, the shaft 13, the boss 14, and the A and B scrapers 18 and 19 are removed. The sand and binder are kneaded by rotation. At this time, the shaft 13 is connected to the spring presser 23,
The boss 14 is pressed downward via the spring member 16, so that the A scraper 18 rotates with its lower edge in strong contact with the upper surface of the bottom plate 9 of the kneading tank 3, and the bottom plate 9 of the molding sand is rotated. Do not allow adhesion to 9. The lower edge of the A scraper 18 gradually wears out due to contact rotation with the bottom plate 9, but due to the pressing action of the shaft 13, the lower edge and the bottom plate 9 are always kept in contact, and there is a gap between them. There will never be any gaps.

As is clear from the above description, the present invention applies a pressing force to the scraping scraper of the kneading machine so that the lower edge of the scraper is always in contact with the bottom plate of the kneading tank. Therefore, even when kneading molding sand for cold boxes, which has strong adhesion and hardening properties, the sand does not adhere to the bottom plate, which greatly reduces the labor and time required to clean the kneading tank after work. .

Further, in the present invention, the bottom plate of the kneading tank can be opened on one side, and the boss to which the scraper is attached can be separated from the shaft, so that the scraper can be easily taken out and cleaned.

Furthermore, in the present invention, if the pedestal 2 and the kneading tank 3 are rotated around the rotating shaft 1, the sand kneading position and the cleaning position of the kneading tank 3 can be provided separately to facilitate handling. It is.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a kneading machine according to the present invention, and FIG. 2 is an enlarged sectional view of section A in FIG. 1. 3: Kneading tank, 4: Motor, 6: Vertical shaft, 9: Bottom plate, 13: Shaft, 14: Boss, 16: Spring member, 1
8: A scraper, 19: B scraper, 23:
Spring presser.

Claims (1)

[Scope of utility model registration request] A vertical shaft 6 that rotates at a low speed is arranged above the center line of the kneading tank 3 having a vertical cylindrical shape, and a shaft 13 that reaches the bottom plate 9 of the kneading tank 3 is connected to the lower end of the vertical shaft 6.
A cylindrical boss 14 having a diameter larger than the outer diameter of the shaft 13 from approximately the middle of the inner cylinder to the upper end is fitted to the lower end of the inner cylinder in a vertically slidable and detachable manner,
A spring member 16 is inserted into a hollow portion defined by the large diameter portion of the inner cylinder of the boss 14 and the outer peripheral surface of the shaft 13, and a scraper 18 for scraping is fitted to the outer peripheral portion of the lower end of the boss 14. The shaft 1 is attached so that its lower edge is in contact with the bottom plate 9 of the kneading tank 3.
3, a spring presser 23 for pressing the spring member 16 is fitted, and the bottom plate 9 can be opened on one side.