DE1257548B - Vibrator screen - Google Patents

Description

GERMAN #M PATENT OFFICE

EDITORIAL

German class: 50 d - 6/30

Number: 1 257 548

File number: S 109722 VI a / 50 d

J 257 548 Filing date: 3rd Mail967

Open date: December 28, 1967

The present invention relates to improvements in vibratory screen shakers.

The present invention particularly relates to devices that can improve the operation of Lead sieves in such systems and prevent the sieves from being closed by a coating sifting material or clogged by adhering particles that are too large.

F i g. Figure 1 of the drawings is an elevation of a circular vibrator screen;

F i g. Figure 2 is a partially cut away perspective view of the device of the invention to improve the operation of sieves.

The vibrator sieve device consists of a base frame 10, on the upper part of which springs 11 are mounted in the form of a ring, so that the base frame is mechanically separated from the vibrator sieve. A vibrator, consisting of the motor 12 and the lower and upper eccentric weights 13 and 14, is mounted by means of the flange 15 in the upper part of the frame part 16 , which in turn is carried by the ring formed by the springs 11. A cylindrical extension 17 is screwed to the upper part of the frame piece 16; this approach 17 has an outlet pipe 18 on one side. An annular piece 19 is attached to the lower part of the cylindrical extension 17 , as a result of which tension is exerted on the outer edge of the clamping plate 20. In the middle of the clamping plate is the pin 21, through which the tension on the clamping ring 23 can be adjusted. The vibrating sieve 22 is attached to the clamping ring 23 , the lower edge of which is denoted by 24. The clamping ring 23 is screwed to the underside of the essentially cylindrical extension 25 which carries the outflow nozzle 26 on one side. The screen 22 is clamped in the clamping ring 23 by a snap ring (not shown) prior to assembly; later, the required tension is set with the help of the center pin 21, the washer 27 and the locking screw 28 .

As stated above, the device is used for separating material to be screened of different sizes by means of the screen 22, which is caused to vibrate by the vibrator 12 and the lower and upper eccentric weights 13 and 14, respectively. When the material to be separated is introduced through the upper sieve 22 , it moves over the sieve due to the shaking movement; the portion of the material to be screened which is too large and not let through goes through the outlet nozzle 26 . The material that has passed through the sieve falls onto the clamping plate or the bowl 20 and finally goes through the outlet pipe 18 . Although vibrator sieve

Applicant:

Southwestern Engineering Company,
Los Angeles, Calif. (V. St. A.)

Representative:

Dipl.-Ing. M. Licht, Dr. R. Schmidt,
Dipl.-Wirtsch.-Ing. A. Hansmann
and DipL-Phys. S. Herrmann, patent attorneys,
Munich 2, Theresienstr. 33

Named as inventor:
Wayne James Auckland,
Burlington, Ontario (Canada)

Claimed priority:

Great Britain May 4, 1966 (19 654)

this arrangement can easily be adapted to the respective requirements in terms of weight and "feed angle" (ie angle by which the lower weight 14 is displaced with respect to the upper weight 13 ) of the screenings to be separated by suitable selection of the screens and appropriate setting of the eccentric weights 13 and 14 can be adapted, the vibrator screen works unsatisfactorily in certain applications.

If z. B. Ordinary wheat flour is finely ground, it tends to cover the sieve, d. That is, part of the flour adheres to the sieve wires and occasionally covers the sieve openings, so that the flow rate of the flour particles through the sieve drops and the sieve device even clogs will. In a similar way, goods to be sieved, such as fine zinc powder or finely ground adipic acid, repeatedly cause malfunctions of vibrator separating sieves.

In the improvement of the present invention, it has been found that by attaching a hollow cylinder 30 to the very top end of the pin 21, the difficulties encountered in sieving flour, zinc powder and adipic acid are eliminated; the hollow cylinder is partially filled with freely movable metal balls which collide with one another and against the walls of the cylindrical container 30 during the vibration of the machine. This metal

709 710/298

Claims (5)

balls 31 can be of any suitable diameter, e.g. B. between 5 and 23 mm; It is only important that the container 30 is not completely filled with the balls and that enough space remains free in the cylindrical container that the balls can collide with one another and against the side walls of the container 30 without hindrance. F i g. 2 shows an embodiment of the container, the side walls being shown partially cut away in the figure. The container 30 has cylindrical side walls and flat bottom and top surfaces 32 and 33. A hole is drilled through the bottom surface to enable the container to be attached to the pin 21 (Fig. 1); the container is screwed to the pin 21 with the screw nut 33. To fill the container, a hole is provided in its upper part 33; when the arrangement is assembled and the balls are filled, the hole is closed with the screw 34. The height of the cylindrical container 30 should be smaller than the distance between the clamping rings 23 and 19; the height to which the container is filled with metal balls, which set the sieve in irregular movements, should be a fraction of the height of the container and not its full height. Since the device works more efficiently when the material fed to the sieve moves from the center to the outflow nozzle 26 inserted on the periphery, it is advisable to attach a funnel-shaped feed device 35 in the center, on the pin 21. In another embodiment, the hopper 35 is attached to the insertion device (not shown). When the hopper 35 is attached to the center pin 21, it may have a number of openings 36 at or near its base; The base of the conical filling funnel 35 can then be made flat, with a through hole for the center pin 21. It is not immediately apparent that the attachment of the cylindrical container 30 with the metal balls 31 can noticeably affect the operation of the vibrator screen, but it was found during operation that these additives increase the throughput and the length of time during which the sieve can be operated without interruptions for cleaning work, if the device is used for sieving difficult-to-separate materials. This is apparently due to the fact that the metal balls 31 when hitting the container 30 result in a different type of vibration on the central pin 121, which in turn transmits these vibrations to the sieve. This results in a more effective vibration of the sieve and at the same time avoids its clogging, which was not achieved in the previous state of the art. Some vibrator screen devices do not have a center pin 21. In these devices, devices other than the center pin 21 and the circular bowl 20 are provided in order to exert a tensile stress on the screen 22. In such an embodiment of the device, the cylinder container 30 with the steel balls 31 can then be attached over the center of the screen 22 by means of struts which are fastened to the clamping ring 23 or to the side walls 25. In this way, the shaking movement, which occurs due to the impact of balls on the side walls or on other balls, can be communicated to the sieve, even if a center pin 21 is missing. The balls 31 must be made of a hard material, preferably a metal, such as. Steel, to prevent clogging of the screen and to improve the operation of the screen mechanism for separating hard, powdery substances prior to crushing. Patent claims: 1. Vibrator sieve, consisting of a cylindrical housing, a flat sieve for receiving the material to be sieved, a shaking device to set the housing and the sieve in vibration so that the material to be sieved moves on the sieve to remove the coarser portion of the material to be sieved to be removed from the rod, characterized by movably arranged, driven by the vibrator (12), shock-generating bodies (31) and a container (30) for the shock-generating body, which is mounted above the screen (22) so that it holds the shocks transfers to the sieve. 2. Apparatus according to claim 1, characterized in that the shock-generating body (31) consist of a plurality of metal balls. 3. Apparatus according to claim 2, characterized in that the container (30) is a cylinder which is located above the sieve (22). 4. Apparatus according to claim 3, characterized in that the vibrator screen additionally contains a center pin (21) which carries the screen and the means generating the impacts. 5. Apparatus according to claim 4, characterized in that a funnel-shaped introduction device (35) are connected to the center pin (21) in order to feed the screenings to be separated to the center of the screen. 1 sheet of drawings 709 710/298 12.67 © Bundesdruckerei Berlin