DE1060560B - Forming machine for boxless forms - Google Patents

Description

GERMAN

The invention relates to a boxless molding machine Forms with dosed sand application with uniform sand density. For molding machines according to the Principle of the so-called boxless molding, the sand is molded in boxes, but after production The boxes are removed from the sand mold from this mold, leaving the sand mold without molding boxes is poured out. In previously known machines, the known turning method is often used. A box is filled with sand and turned after placing a model or a model plate. After filling the second box, the first, turned box with the now under the The model plate lying on the box is placed on the second box and the sand in both boxes against the Pressed model plate. Then the model plate is removed and the two boxes are placed on top of one another. at However, these machines, which work according to the turning process, have some shortcomings. The molding boxes must be guided exactly to one another. However, this guidance loses its accuracy when the Work out guide bushings so that the boxes are offset from one another.

Furthermore, molding machines for boxless forms with spindles fixed to the side are dust-tight Led upper and lower box became known, the smooth inner surface of which extends from the lower edge of the Lower box tapered evenly up to the upper edge of the upper box; to this machine includes a press cylinder arranged in its bottom, as well as one that can be swiveled between the boxes on both sides equipped model plate, a pressure piece that can be swiveled in over the boxes and a Sand shaft closed by a slide.

These machines, too, have defects such as box misalignment caused by turning, among other things the boxes is caused, is largely avoided, do not meet the requirements.

So with all known machines, the production of small usable castings failed because of the flawless ones Feeding a dosed amount of sand. While a handformer according to his experience the sand is prepared and poured into the mold in such a way that a uniform density in the sand structure arises, in known machines the sand is whirled into the molding boxes and forms in the slipstream of the models to be formed often cavities or spaces with a less dense sand structure, whereby also Many different sand structures arise within the molding box.

The object of the invention is now in a molding machine for boxless forms with on the side fixed spindles guided upper and lower

Applicant:

Erich Sander,
Asbeck via Gevelsberg (Westf.)

Erich Sander, Asbeck via Gevelsberg (Westf,),
has been named as the inventor

box and a pressing cylinder arranged in the bottom of the machine, and one between the boxes swivel-in model plate, a pressure piece that can be swiveled in over the boxes and a to create a facility with which a sand shaft closed by a slider Evenly dense sand structure can be achieved in the mold and, as a result, also the production of smaller ones flawless cast parts is possible.

This object is achieved in that the sand shaft through the upper box to the lower box can be lowered and is assigned to a funnel with closure plate, the closure plate at opened sand shaft and closed slide for refilling the dispensed sand amount is actuated.

A further feature of the invention is that the filling funnel is displaceable on its closure plate is stored.

Finally, one feature is also characterized in that the filling funnel has a chute is provided, which in every position below the tipping point of a continuously conveying bucket elevator stands through which the hopper sand has to be fed in very small quantities.

With these arrangements, the essential shortcoming of the known designs of molding machines is in the incorrect sand supply, eliminated and an even sand pressure and A uniform sand structure is achieved in both the lower and upper boxes.

Thus, the production of a perfect shape and thus the production of perfect cast parts is guaranteed.

In the drawing, the subject matter of the invention is shown in an exemplary embodiment.

The drawing shows a molding machine in longitudinal center section.

909 559/95

Claims (3)

The molding machine is built on a base plate 1 which is mounted on rollers 2 so that it can move. A frame 3, in which spindles 4 are mounted in bearings 5, is fastened to the base plate 1. The boxes 7/8 run on the spindles 4 with sockets 6. Between the sockets 6 and the boxes 7/8 overlapping plates 9 which cover the bearings in a dust-tight manner are arranged. A plunger 10, which is guided in a cylinder 11 fastened on the base plate 1, is arranged under the boxes 7/8. A pressure plate 14 and a frame 15 for receiving a model plate 16 fitted on both sides are pivotably mounted around an axis 13 fastened to the frame 3 with bearing blocks 12. On the frame 3 there is a guide plate 17 which serves to guide a sand shaft 18 which moves vertically with pistons 19 in cylinders 20. The sand shaft is closed at the bottom by a sand slide 25. Above the sand chute 18 there is a filling funnel 21 which is filled by a bucket elevator 22/23 which supplies the sand in very small quantities. The filling funnel 21 is laterally displaceable on a plate 24. To produce a sand mold, the machine is moved to the prepared sand, which is conveyed by the bucket elevator 22/23 into the filling funnel 21 and the sand chute 18. The pressure plate 14 and the frame 15 with the model plate 16 fitted on both sides are pivoted back, the sand shaft is lowered into the upper opening of the lower box 8 and the sand slide 25 is opened. During this movement of the shaft 18, the hopper 21 moves laterally and is closed by the plate 24 so that no more sand can fall. After filling the lower box 8, the sand slide 25 is closed, whereby the sand is smoothed off. The sand chute 18 is raised and the returning hopper 21 fills the chute 18. After swiveling the model plate 16 between the two boxes 7/8 and placing the upper box 7, the upper box 7 is filled in the same way as the lower box 8. The sand that is poured in has the same tightness in both boxes 7/8, since the sand shaft is filled up after each removal and so the same column of sand presses on each box. Now the pressure plate 14 is swiveled in and the plunger 10 with the boxes 7/8 and the pattern plate 16 is raised, the plunger 10 moving faster than the other parts. The sand is pressed between the press plate 27 of the press block 10 and the pressure plate 14 against the model plate 16 equipped on both sides. After completion of the pressing, the entire device is vibrated in order to achieve a loosening of the model plate. Then the pressing plate 27 is lowered with the lower box 8, while the upper box 7 is held in the uppermost position. An adjusting device 26 holds the pressure plate 27 in the horizontal position and ensures that the pressure piston 10 drops evenly. Then the lower box 8 lowers by itself and detaches itself from the model plate, which is equipped on both sides. The frame 15 with the model plate 16 can then be swiveled out. Finally, the upper box 7 is lowered onto the lower box 8 and the finished sand mold is pushed out of the two boxes by the plunger 10 upwards. It goes without saying that before the upper box 7 is filled, a sprue is plugged onto the model plate 16 and is removed before the model plate 16 is pivoted back. The finished sand mold is removed from the machine on a plate previously placed on the press plate 27. The conveyor belt of the bucket elevator 22 is moved for ao better processing of the sand when it is returned through the hopper 21, so that the blades constantly move the sand in the hopper 21. Patent claims: 1.Molding machine for boxless forms with top and bottom spindles guided on laterally fixed spindles and lower box and one arranged in the bottom of the machine press cylinder and one Model plate that can be swiveled in between the boxes and one that can be swiveled over the boxes Pressure piece and a sand shaft arranged above it, closed by a slider, characterized in that the sand shaft (18) through the upper box (7) to the lower box (8) lowerable and assigned to a funnel (21) with closure plate (24), the closure plate with the sand shaft open and the slide (25) closed to refill the dispensed amount of sand is to be actuated. 2. Molding machine according to claim 1, characterized in that the hopper (21) its closure plate (24) is slidably mounted. 3. Molding machine according to claim 1 and 2, characterized in that the filling funnel (21) is provided with a chute, which in every position below the tipping point of a continuously conveying bucket elevator (22) through which the hopper (21) sand in small quantities is to be supplied. Considered publications:
German Patent Nos. 806 274, 654 899, 168, 537 474, 531 594, 497 740, 493 183, 407 166; U.S. Patent No. 2,243,092. 1 sheet of drawings © 909 559/95 6.59