Improvements in Feed Apparatus, Applicable for Roller Grinding Mills and other Machinery where a very Regular Feed of Pulverulent or Granular Matter is required. APPLICABLE FOR GRINDINGLS AND MACHINERY WHERE
Year: 1884

page_text: Improvements in Feed Apparatus, Applicable for Roller Grinding
Mills and other Machinery where a very Regular Feed of
Pulverulent or Granular Matter is required.
I PIETER VAN GELDER, of Sowerby Bridge, in the county of York, Milling
Engineer, do hereby declare the nature of my said invention for IMPROVEMENTS
IN FEED APPARATUS, APPLICABLE FOR ROLLER GRINDING MILLS AND
MACHINERY WHERE A VERY REGULAR FEED OF PULVERULENT OR GRANULAR
MATTER IS REQUIRED, to be as follows:-
OTHER
This invention has for its object the improvement of roller mills such as those
for which I applied for Letters Patent dated January 30 1884 N° 2390.
It
In the said application I showed an arrangement of friction wheels and rolls.
I have found that to work well, the distance between these rolls must be regulated
to about the 300th of an inch, and also the feed must be very carefully regulated.
My present invention is therefore a new feeding apparatus applicable for these rolls.
At the bottom of a feed hopper I place a cylinder, pitted all over with uniformly
sized small cavities like one of my patent cockle rolls. The surface of the roll
surrounding the pits is perfectly smooth and cylindrical a rubber doctor fixed to
the back of the hopper prevents any stuff falling out in that direction, the front of
the hopper consists of a radial board, plate or blade kept in place by a regulated
spring, but otherwise hinged or elastic so as to give way a little with pressure.
is obvious that if this plate scrape the cylinder no material can pass it when the
cylinder revolves except what is held in the pits or pockets. If however by extra
pressure in the hopper the plate is pressed out of the radial line, a little material
can pass, and in proportion to the sine of the angle that the plate makes with the
radial line, so is the extra feed increased. The feed from the cylinder. falls on to a
sloping plank, hinged at or near the upper end, and from this on to another sloping
plank similarly hinged, which delivers it on to the rolls. These two planks are
linked together with adjustable link. The lower one rests by a doctor against the
upper side of one of the rolls, so that in proportion as the board and doctor
approach the vertical, so as to fall off from the roll, so is the possible amount of
feed allowed to pass increased. The upper sloping plank rests at its pivot on a
counter-weighted lever, having at the free end a rubber roller bearing against a
toothed wheel geared to run at a considerable speed relatively to that of the feed

page_text: cylinder. The action of this toothed wheel is to give a slight and very quick
tremor to the rubber roller borne up against it by the counter-weight. Through
the roller and its lever, the tremor is imparted in turn to the two sloping hoards.
By this means as the feed cylinder drops on to the upper board its numerous
pocketsful of material in little heaps, the latter are shaken down to a uniform even
layer by the time they have travelled down the two sloping boards to the rolls.
The angles of the two sloping boards can be regulated at pleasure to suit different
material. Where there are four rolls the feed mechanism is doubled, the two
shaking levers being superimposed at their free ends so that the shaking of one
shakes the other.
In the above description I have simply described my experimental apparatus,
but it is obvious that the same can be widely varied in form and arrangement
without departing from the principles of my invention. One sloping board could
take the place of two, but I do not recommend this plan, as the fall from one board
to the next is very useful-or a less tremulous shaking apparatus could be applied
to a board or boards formed of a series of short sloping steps. The numerous falls
making up for the less shaking.
One advantage of my apparatus is this, that the rolls being regulated as regards
distance apart by their friction wheels, should the feed go wrong, or a stoppage
occur in them and not in the feed, they can be drawn apart, the surplus feed
rapidly passed through and immediately after, the rolls can be placed again in
position without re-adjustment. This form of feeding roll is applicable for almost
any machinery where a very uniform feed of granular or pulverulent matter is
required.

page_text: Improvements in Feed Apparatus, Applicable for Roller Grinding
Mills and other Machinery where a very Regular Feed of
Pulverulent or Granular Matter is required.
I, PIETER VAN GELDER of Sowerby Bridge in the County of York, Milling
Engineer do hereby declare the nature of my said invention for IMPROVEMENTS
IN FEED APPARATUS APPLICABLE FOR ROLLER GRINDING MILLS AND OTHER
MACHINERY WHERE A VERY REGULAR FEED OF PULVERULENT OR GRANULAR
MATTERS IS REQUIRED and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
This invention has for its object the improvement of roller mills such as those
described in the specification of Letters Patent dated 30th January 1884 N° 2390.
In the said specification is shown an arrangement of friction wheels and rolls.
I have found that to work well the distance between these rolls must be regulated
to about the 300th of an inch, and also the feed must be very carefully regulated,
and evenly distributed, as if otherwise the material mounts on itself, and is ground
instead of being granulated.
This present invention relates solely to the feed apparatus though in the
drawings I have for the sake of clearness shown the whole machine and herein-
after have described the several parts of it in detail in the same manner as they
are described in the specification of the aforesaid Letters Patent N° 2390 of 1884.
Referring to the drawings:
Figure 1 is a diagram drawing of the machine in side elevation.
Figure 2 a plan of rollers etcetera, with upper works removed.
Figure 8 section of entire machine.
Figure 4 section of feed apparatus.
Figure 5 elevation of feed apparatus constructed on precisely the same principle,
but for machines having a grosser feed.
A is the framework of the machine B B B B four rollers made preferably of
the very hardest chilled cast iron; of these B and B¹¹¹ are in sliding bearings à d³
and B and B in stationary ones d d but free to adjust themselves to the shaft.
These four rollers are not turned truly cylindrical but with a slightly larger
diameter toward the centre than at the sides, the amount of difference being a few
thousandths of an inch at most. This is to allow for a very slight amount of
elasticity which I have found to exist in the rollers and shafts, C C C 0111 shafts
of rollers. D D¹ D₁ D1 bearings of same. The bearings or brasses D D¹ D" Du
are fitted into the blocks d d' d' d³, these blocks are fitted between the slides, A¹ A¹
carried by the framing and those carrying the outer rollers slide freely to and fro
controlled by the springs. K are oil tubes through which oil is supplied to the
bearings of the rollers. e oiling rollers working in a well in the bearings, k oil
tubes fitted with caps through which the spent oil may be drawn off from the
bearings of the shafts E E¹ E E volute springs hearing against the bearings on
one side and the nuts i on spindles e e¹³ ³ on the other, Spindles e¹ and eª and

page_text: their springs E¹ E² are not absolutely required, while the apparatus is at work, but
are very useful when a stoppage occurs to automatically draw the rolls of each pair
respectively apart the moment the pressure of the levers, hereafter described is
taken off. Levers f³ f³ oscillating on pins f f bear against the ends of spindles e
and respectively, and are themselves actuated by links f and f¹ and handle
levers F FI
In the drawing, F is shown in the position taken when the pressure on the roll
bearings is released F¹ in the position where it is full on. GG¹ G¹¹ G¹¹¹ are the
friction pulleys. In the case of rolls B and B for coarser stuff, their pulleys G
and G¹¹ are made with a larger difference in diameter than in the case of the other
pair for finer stuff. These pulleys must be made of hard and perfectly homogenous
material. After numerous experiments I have found pulleys of the hardest chilled
cast iron to be the best. These are set in their shafts by conical keys g g¹ g³ g³ as
I find that ordinary keys cause a slight wobbling or eccentricity fatal to good work.
HH' driving pulleys. I l' are exit hoppers. JJ are counterweighted scrapers
oscillating freely on shafts jj and armed with counterweights J¹¹ to keep them
bearing against the rolls, the blades of these scrapers are made as separate pieces,
and bolted to the bell cranks, so that they can be adjusted for wear. KKKK"
oil tubes for oiling the bearings D D₁ D¹¹ D¹ respectively. kk k³ ³ tubes for
carrying off dirt or grit from the bearings, which latter are of the ordinary type
with an oil chamber and wooden or other cylinder floating in the oil against the
bearing as shown in dots. kkkk caps for said tubes. L L L L india
rubber valves or doctors to prevent flour or other material passing over the rolls
the wrong way. M M¹ feed hoppers. m m¹ openings on hoppers M M¹ for exit
purposes. m² m³ india rubber valves or doctors bearing against the feed rolls
hereafter described, and closing the back of the hoppers against the passage in this
direction, against the material to be ground. m m³ sliding doors hinged at m16 m17
respectively, so as to enable the lower part to open sideways while the upper part
actuated by the regulating mechanism is susceptible only of a longitudinal sliding
motion in guides. m m springs bearing against the hinged doors tending to
keep them closed. m m³ screws for adjusting said springs by bringing their
collars m¹ m19 nearer or further from their nuts in stationary bars or brackets
mm13 m10 m11 hand wheels of said screws. m14m15 india rubber abutments for
the doors m m³ to rest against.
N N' india rubber rollers bearing against slides m m and used for raising or
lowering them and thus regulating the amount of feed. nn¹ shafts for said rollers
carried in bearings n n and worked by hand-wheels n² n³. n° n7 winged set
screws for clamping said shaft. n³ n³ slide bars bolted to and carrying slides m
or m³ as the case may be, and sliding between rollers N N¹ and no or n
respectively. 10 n" flanged rollers free to rotate as the slides n³ nº respectively
are raised up and down; these rollers are carried on brackets n¹º n13.
00¹ removable casing at bottom of hoppers M. M¹. P P¹ hinged doors into
casing 0 0¹. p³ på inlet openings for air. QQ shaking boards upon which
the feed falls in little hillocks from the pitted roller S S hereafter described.
QQ two other shaking boards receiving the feed from the first two and having
flexible rubber ends resting on the rolls B¹ B", the flexibility being sufficient to
allow the board to be shaken without the end breaking contact with the roll.
993 shafts carrying shaking boards QQ, and q q³ similar shafts carrying shaking
boards QQqq adjustable links linking QQ to Q and Qu respectively.
96 more clearly shown in Fig. 6 weighted lever keyed to the shaft q and having
continuation 98 beyond carrying an india rubber roller q in bearings q10. This
roller is pressed by the counterweight against the rapidly revolving toothed
wheel q¹ which is geared to the toothed wheel q¹³ on the shaft of feed roller S
and by pulleys R and R, and a band as shown drives feed roller S¹. q7 is a lever
similar to q. It is keyed to q' and carries on its continuation qº a projection q
which is pressed against q10 and takes the dithering or shaking motion therefrom,
communicating it through shaft q³ to shake board Q and through it and rod g² to

page_text: shake board Q S S¹ are turned cylinders pitted all over with little pockets,
like a cockle cylinder. T exhaust passage feading to exhaust fan. t exit for
exhaust fan.
The mode of action is as follows:
The coarser material is fed into M the finer into M¹. Referring to the M half of
the apparatus only, the other half being practically a duplicate of this, the feed lies
on roller S and door m', if the latter be firm against the roll S nothing can escape
between except the contents of the little pockets; these pockets being uniformly
distributed and uniform in size, discharge the material in little hillocks at even
distances on shake board Q. The incessant dithering shakes these down, and the
material sliding down the board falls in a nearly even thin sheet, on to slide
board Q where it is further equalized by continued shaking. From the end of
this it falls on to the roller and passes between the rubber end of this shake board
and the rolls B B¹. The levers being set in the position shown at F1, the mill is
worked with an even continuous feed; should at any time the feed go wrong, or
the rollers have to be stopped while the feed is going on, or other action occur
by which an increase of feed occurs too great for the rollers to grind, the levers
are put in the position shown at the F end in the drawing; the springs E then
pressing between their bearings and nuts push the bearings of roll B outward.
The two friction rollers no longer touch each other, roll B stops, but roll B¹ runs
on and works off the superfluous feed. By simply turning handle F back into a
similar position to that shown at F, the rolls are again placed in gear, the pulleys
acting as distance pieces; thus while in an ordinary mill it might take an hour
or two after the rolls have been thrown out of gear to get them set exactly right,
by my frictional arrangement they can be instantly re-adjusted to their exact right
position,
Seeing I have differential speeds on the pulleys, the wear is uniform and is very
slight. By having a series of change wheels differing say a hundredth of an inch
in circumference, and changing as required, the distance apart of the rolls is exactly
regulated, and the slight wear that in time takes place, can be made good by
change of wheels.
The power of the friction rollers to resist slipping must be at least 25 per cent
more than the power expended in grinding or crushing. For heavy grinding the
rollers must therefore be broad and, as shown in the drawing Figure 2, I use
broader pulleys for the fine grinding rolls than for the coarser.
The material passing through the rolls is licked off by scrapers J when these are
used, (but they are not necessary with very coarse granulation) and falls into
hoppers I. Throughout the description and drawings, two mills in one machine
are described and shown, but it is obvious that what will do when two mills are
used, can be applied to a single mill.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1st. The manufacture and use for feeding purposes of a cylinder (S) evenly pitted
all over its surface, revolving at the base of a hopper, or its equivalent with a
device for regulating the amount of opening or of pressure between lower edge of
the hopper or its equivalent, and the cylinder, or for scraping the surface of the
cylinder, so that only the contents of the pockets are fed out.
2nd. In combination with a roller mill a cylinder having numerous hollows,
flutings or depressions on its surface delivering material from a hopper or its
equivalent, and a shaking or dithering device below, substantially as described
upon which the feed falls, whereby the little hillocks or ridges of material delivered
from the pits or pockets are shaken down to a uniform layer before entering
the rolls.
3rd. The mechanism for regulating the feed from the rollers, substantially as
shown, in combination with a feed apparatus delivering the feed in hillocks or

page_text: ridges, the combination of shaking boards delivering the one on to the other and
linked together, substantially as described.
4th. The shaking apparatus consisting of a counter-weighted lever having
running thereon at or near the end a roller, preferably of india rubber, said
roller pressing against a rapidly revolving toothed or serrated wheel, substantially
as described.
5th. In combination with a shaking board delivering material to a pair of rolls,
a flexible india rubber end to that shaking board resting on the roll, whereby the
shaking can be accomplished radially (with the centre of oscillation at the higher
end) and yet the lower end never rise from contact with the roll.