Bypass mechanism for magnetic separator

A method utilizing a simple mechanism to circumvent the effect of the magnetic conveyor head (12) of a magnetic separator (11), whereby ferrous material such as steel cans can be diverted from the stationary reject chute (13) to go instead to the place where nonferrous materials go. The mechanism, called a movable chute (14), is actually a movable extention of the stationary reject chute (13) and pivots up or down on a hinge device (15) that connects it to the stationary reject chute (13). It can be secured in the up position by a latching device (16). It can be maintained at a constant angle in the down position by a stopping device (17). Edges (18) to the movable chute are provided to prevent material from falling off the sides. These edges are mounted either on the movable chute or on the sides of the magnetic separator. In the latter case they are called stationary guides (19). When the movable chute (14) is in the up position it forms a straight extension to the stationary reject chute (13). When it is in the down position it creates a downward chute that directs ferrous material away from the stationary reject chute (13) and into the chamber where ordinarily only nonferrous material would go.

FIELD OF INVENTION 
This invention relates to magnetic seprrators, and more particularly to a 
movable chute for magnetic separators used in recycling aluminum and steel 
cans. 
BACKGROUND OF THE INVENTION 
The magnetic separator used by the aluminum can recycling industry is a 
belt conveyor that runs over a magnetized pulley referred to as a 
"magnetic conveyor head". Any ferrous material such as steel beverage cans 
is attracted to the magnetic conveyor head. Whereas the aluminum cans fall 
off the conveyor as soon as the upper run of the conveyor belt beneath 
them comes to the magnetic conveyor head and begins to follow it around, 
the steel cans are drawn to the magnet. Only after the steel cans are 
carried half way around the magnetic conveyor head, and the conveyor belt 
actually begins to leave the magnet do they fall off. At this point the 
steel cans are diverted into a separate chute referred to as the 
"stationary reject chute " which sends them to the reject barrel. 
Very elaborate equipment has been developed over the years to automate the 
recycling of aluminum beverage cans. Among other things, the magnetic 
separator is often combined with a hydraulic press referred to as a 
"densifier" which compresses the cans into small bricks called "biscuits". 
A mixture of cans can be dumped into the hopper of a separator/densifier. 
In a single operation the steel cans are separated from the aluminum cans, 
the aluminum cans are densified, and the steel cans rejected. 
Recent trends in the recycling industry, however, are beginning to outdate 
some of this expensive equipment. For one thing, steel cans have begun to 
have value. The broadening base of the recycling industry has turned 
attention to steel cans. There is still a need to keep the different 
metals separate. But instead of throwing the steel cans away, it has now 
become desirable to biscuit them up and sell them. The problem which 
arises with conventional equipment is steel cans cannot be processed by 
the automated equipment because the magnetic conveyor head keeps rejeting 
them. 
There are two solutions to this problem namely, buy expensive equipmetn 
that will process steel cans or somehow bypass the magnetic conveyor head 
on the separator. My invention is a very simple mthod to circumvent hte 
effect of the magnetic conveyor head. By permitting existing eqipment to 
do double duty, my invention eliminates the need to spend hundreds and 
even thousands of dollars on additional equipemtn. 
SUMMARY OF THE INVENTION 
It is an object of this invetion to provide a conveyor apparatus having a 
magnetic head with a bypass, a movable chute that permits a luminum or 
steel cans to be selectively directed int oa densifier or the like. 
In carrying out the invention, I provide a conventional magnetic head 
conveyor apparatus with a mopvable chute adjacent the discharge end of the 
conveyor. The chute is shiftable between elevated and lowered positions. 
When the chute is in the elevated position, it serves as a continuation of 
the lower wall of the stationary chute and supports and directs steel cans 
or the like to a collection point. Aluminum cans are discharged from the 
conveyor belt into a densifier or other collection station. When in the 
lower position, the chute serves to direct steel cans into a densifier or 
other collection station. 
The use of my novel chute with a magnetic head conveyor saves money, space, 
and labor. It would be possible, for instance, to but an additional 
conveyor--one without a magnet--that would run steel cans into the 
densifier. By using one standard industry item, however, and merely 
incorporating an inexpensive modification, a great deal of money can be 
saved. 
Furthermore, my invention ultimatley saves space. Between the need to 
economize and the need to process large quantities of material in oreder 
to make any money, a typical recycling shop is always short of space. By 
combining into one machine the work of two machines, the need to find room 
for another piece of equipment is eliminated. 
Thirdly, my invention saves labor. Without my invention the operator would 
be required to physically move either one machine into place or the other 
depending upon whether he wanted to run steel cans or aluminum cans. My 
invention requires only a very simple adjustment, taking but a few 
seconds, and one versatile machine is ready to process either steel cans 
or aluminum cans.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A typical separator/densifier, designated generally by the reference 
numeral 11, is illustrated by FIG. 1. This particular drawing closely 
resembles the CD500 Can Densor manufactured by CP Manufacturing, Inc. of 
National City, Calif. Physical appearance of separator/densifiers varies 
from model to model and from manufacturer to manufacturer but the basic 
function of all separator/densifiers is the same. My novel chute is a 
modified component of a typical separator/densifier 11. 
The conventional separator/densifier 11 includes a stationary frame 13. The 
stationary frame 13 includes side walls 13a and a bottom wall 13b. A 
conventional endless belt type conveyor 12a is trained about pulleys 
including the upper magnetic pulley which defines the magnetic conveyor 
head 12. The belt conveyor 12a is provided with conventional transverse 
elements 12b of well-known construction. 
A conventional densifier 20 is provided for compacting and compressing the 
cans in a well-know manner. A support brace 20a extends between and 
connects the separator 11 and densifier 20 so that the separator is 
disposed in an upwardly inclined condition. 
Referring now to FIG. 1, it will be seen that, in a mixture of aluminum 
cans AL and steel cans ST, the aluminum cans AL are discharged from the 
conveyor belt 12a as the upper run thereof passes around the magnetic 
conveyor head 12. The aluminum cans AL fall into the densifier 20, while 
the steel cans ST are held against the lower run of the conveyor belt 12a 
until the steel cans ST are moved beyond the magnetic field effect 
produced by the magnetic conveyor head 12. At this point, the steel cans 
ST fall upon the lower wall 13b of the stationary frame 13 and slide 
downwardly therealong by action of gravity until these steel cans fall 
through an opening at the lower end of the bottom wall 13b into a reject 
barrel 21. 
Referring now to FIGS. 2 through 6, it will be seen that the 
separator/densifier 11 is provided with my novel movable chute 14. The 
movable chute 14 is movable between an upper or elevated position, as 
shown in FIG. 4, and a lowered position, as shown in FIGS. 3, 5, and 6. 
When the movable chute is in the elevated position, it functions as a 
continuation of the bottom wall 13b, and is used in the elevated position 
when aluminum cans are (separated and) directed into the densifier 20. 
However, when steel or ferrous containing cans are to be compressed, the 
movable chute is lowered, and the steel cans fall upon the movable chute 
14 ard are directed by action of gravity into the densifier 20. 
Referring again to FIG. 3, it will be seen that the movable chute 14 
includes a pair of substantially parallel side wall elements 14a that are 
integrally formed with the chute 14 and extend upwardly at right angles 
thereto. In the embodiment shown, the chute is hingedly connected to the 
upper end of the bottom wall 13b chute by a hinge 15. A latching device 16 
is also provided and releasably latches the movable chute 14 in an 
elevated position as seen in FIG. 4. Stopping element or device 17 is 
provided and limits swinging movement of the movable chute from the 
elevated position to the lowered position as seen in FIG. 5. With this 
arrangement, the chute can be readily latched in the elevated position for 
processing aluminum cans through the densifier and may be unlatched to 
permit swinging of the movable chute to a lowered position for processing 
of steel cans through the densifier. 
Referring now to FIGS. 4, it will be seen that the movable chute 14 is 
shown in the up position. It will further be noted that in this position 
there is no substantial difference between a conventional separator and a 
separator with the movable chute, since the movable chute 14 contitutes an 
upward continuation of the fixed chute. 
FIGS. 3, 4, 5 illustrate the use of the stopping device 17. When the 
movable chute 14 is in the elevated position, the latching device 16 
secures it in place. When the movable chute is unlatched and lowered to 
the down position as best seen in FIG. 5, the stopping device 17 limits 
downward movement of the movable chute and holds it out at about the same 
downward angle as the bottom wall 13b of the stationary frame 13, but in a 
different direction. 
FIG. 5 shows the movable chute 14 in the down position. Neither the length 
nor the width dimensions of the movable chute are critical, since these 
dimensions are contingent on the equipment to which it is installed. The 
movable chute is always as wide as the bottom wall 13b to which it is 
attached. The length of the movable chute must be kept at a minimum 
without becoming so short that it fails to intercept all material that 
drops down from the magnetic conveyor head 12. Ihe strength of the magnet, 
the speed of the conveyor belt, the distance between the belt and the 
chute, and the nngle of incline are all factors that would determine the 
length of the movable chute. 
FIG. 3 shows that the movable chute 14 has longitudinal side walls or edges 
14a, 2"-4" high that are fastened to each side of the movable chute. FIG. 
6 shows a modified form of the novel chute attachment. In FIG. 6 it will 
be seen that the stationary guides 19 are fastened to side walls 13a of 
the stationary frame 13 of the magnetic separator in order to prevent 
material from spilling off the sides. 
FIG. 2 illustrates how the movable chute 14 circumvents the effect of the 
magnetic conveyor head 12 allowing steel cans to drop into the hopper of 
the densifier. Notice how the movable chute can be lowered on its hinge 
device 15 so that instead of sending the steel cans down the bottom wall 
13b of the stationary frame 13, it diverts the steel cans into the hopper 
of the densifier. 
Normally the bottom wall 13b of the stationary frame 13 of a conventional 
magnetic separator 11 is one solid piece of steel that begins just below 
the magnetic conveyor head 12 and continues down to a point just above the 
reject barrel. Steel cans slide down this chute on their way to the reject 
barrel. 
In the embodiment shown, the movable chute 14 is actually the upper portion 
of the bottom wall 13b of the stationary frame 13. Instead of making the 
bottom wall 13b out of one solid piece of steel, I chose to make the 
bottom wall out of two pieces of steel, including the movable chute 14, 
connected by a hinge device 15. 
The movable chute 14 pivots up or down on the hinge device 15. To hold it 
in the up position the latching device 16 as seen in FIG. 4 is provided. 
This latch may be a magnet. It may be an eye and a hook. It may be a steel 
pin inserted into two holes that line up with each other. It may be any 
other kind of latch. 
When the movable chute 14 is unlatched it pivots down until it is slanting 
down at about the same angle as the stationary reject chute 13--except 
that it points in the opposite direction. In the case of the CD500 Can 
Densor the leading edge of the movable chute comes to rest on a cross bar 
of the densifier. For other models it might be better to weld a permanent 
stop to the bottom side of the movable chute. To be able to adjust the 
angle, a link chain and hook could be used. 
If the operator has a quantity of steel cans that he wishes to process, all 
he needs to do is lower the movable chute 14. This sends all the steel 
cans into the densifier. When the operator is finished processing steel 
cans and wishes to process aluminum cans, all he needs to do is to raise 
the movable chute and latch it in the up position. 
This is a proven invention with a definite economic benefit. Though 
versatile enough to be adapted to virtually any separator/densifier 
equipment on the market, it has been put to use on the CD500 Can Densor 
manufactured by CP Manufacturing, Inc. of National City, Calif. 
I think it is evident how this invention can quickly, easily, and 
inexpensively fill a growing need in the recycling industry, especially in 
the recycling of steel cans. The invention lends itself to the manufacture 
of an inexpensive conversion kit that can be installed onto existing 
equipment already in the field. This not only increases the value of 
existing equipment, but it also prevents equipment that was originally 
designed exclusively for aluminum cans from becoming obsolete. 
Furthermore, it provides an inexpensive way to build versatility into new 
and expensive recycling equipment. 
My invention makes a tremendous improvement on the CD500 Can Densor. It can 
easily be adapted to improve other separator/densifier machines. 
Furthermore, it will work wherever there are magnetic separating machines, 
even where such machines are not designed specifically for cans. Because 
of this, the scope of this invention should be determined by the appended 
claims and their legal equivalents, rather than by the examples given.