Improvement in Automatic Release Devices for the Rolls of Rolling Mills.
Year: 1899

page_text: Date of Application, 4th July, 1899-Accepted, 4th Nov., 1899
COMPLETE SPECIFICATION..
Improvement in Automatic Release Devices for the Rolls of Rolling
Mills.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings,
in the County of London, Chartered Patent Agent, do hereby declare the nature
of this invention (as communicated to me from abroad by Cornelius Kuhlewind,
of Knoxville Borough; in the County of Allegheny and State of Pennsylvania,
United States of America, Engineer,) and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
My invention relates to the reducing of metal in rolling mills, and is designed
to provide means whereby one of the rolls will be allowed to move away from
the other when the pressure upon them reaches a certain limit, thus avoiding
the breakage and injury to the rolls which has heretofore occurred when tho
pressure has accidentally been raised, as for instance, when the metal sticks in
the rolls,
For this purpose according to my invention I construct the bearing blocks
that are interposed between the trunnions of one of the rolls and the screws by
which pressure is exercised upon the latter with a cylinder and piston charged
with a liquid and so arranged in connection with suitable valve devices that
the piston will withstand the normal pressure which the roll is subjected to
during the rolling process, but when the pressure exceeds a certain limit the
valve device that retains the liquid in the cylinder will yield to the pressure,
and in allowing the liquid to escape from behind the piston, will cause the
piston to move so that the bearing blocks and the roll are relieved of the
excessive pressure.
I will describe my invention referring to the accompanying drawings in which
Fig. 1 is a top plan view, partly broken away on an irregular line, showing one
form of roll bearing, constructed in accordance with my invention. Fig. 2 is
a central vertical section of the same. Fig. 3 is a side elevation. Fig. 4 is an
end elevation showing another form of the bearing and Fig. 5 is a sectional
side elevation of the same.
In the arrangement shewn at Figs. 1, 2, and 3 of the drawings 2 represents
the bearing lilock, which is interposed between the roll trunnion and the press-
ing screw; it is centrally bored out to form a cylindrical cavity within which
is fitted a piston or plunger 3, having an upper reduced portion 4. An annular
ring 5 closes this cavity and is shaped to fit around the upper reduced portion
and also the lower larger portion of the piston as shewn. A flexible packing
ring 6 is secured to the lower face of the piston by a clamping ring 7, this
packing ring being secured at its outer edges by a clamping ring 8 which is
externally screw-threaded to engage the screw-threaded walls of the cavity.
This packing ring will allow the small movement of the piston or plunger
and will effectually prevent the oil or other liquid beneath the piston from
leaking around it. The upper face of the plunger is provided with a transverse
groove having opposite inclined faces 9 which extend parallel to each other, and

page_text: when the plunger is in normal position with its upper end projecting beyond
the ring or cylinder-head 5, these inclined faces are engaged by similar inclined
faces 10 formed by grooving the lower faces of two sliding blocks 11, 11. These
blocks extend 'across the top of the bearing and their ends engage suitable
guiding grooves within the ends of the bearing. The blocks are provided with
inclined upper faces upon which rest the correspondingly inclined faces of a
wedge-block 12 upon which the usual adjusting screws that act upon the rolls
bear, and this wedge-block is guided by two pins 13 which are screwed into the
plunger and are provided with slotted heads entering suitable recesses in the
wedge-block, this block having cross-pin 14 extending through the slots
in the heads.
'
The blocks 11 are normally forced forward by a series of springs 15 extending
through holes in suitable end blocks 16, and into recesses in the blocks 11.
When the springs have been inserted they are held by suitable closing-strips '17.
From the cavity beneath the plunger lead an outlet port 18 and an inlet
port 19. The outlet port leads to a valve chamber 20 formed in a screw-
threaded valve-plug or casing 21. This valve chamber 20 is formed within an
externally screw-threaded sleeve 22 which is secured within the plug, and has a
scries of holes registering with a series of ports 23. The valve consists of a
disc 24 which closes the lower ends of these ports and is provided with a central
boss 25 to which is secured, by a screw-threaded stem, a hollow head 26, to the
upper reduced part of which are secured on each side a series of thin flexible
metal plates 27, which are preferably made of steel. These plates are ground
very thin and are fitted one upon the other, being secured by screws passing
through them into the head. Between the head and the boss is secured a cup
packing whose edges are held by a clamping-ring 28, and to the lower face of
the disc 24 is secured another flexible packing disc 29, the edges of which are
secured within the valve plug by the follower 30. The head 26 is inwardly
bevelled and provided with branch ports as shown, so that any leakage past the
thin plates will be returned to the valve chamber. 31 is a backing plate for
the packing 29, and to which is secured the plug 32 which is externally slotted
and pivotally secured to a lever 33 fulcrumed at 34, and engaged by a stem 35
having an adjusting wheel-nut 36 screwed thereon bearing upon the lever. The
valve 24 is normally pressed in to close the ports 23 by a spiral spring 37 sur-
rounding the stem 35 and bearing against a collar at its end and a stationary
abutment collar 38 upon the frame, the power of the spring being regulated by
the wheel-nut 36:
The ports 23 lead to an annular groove or recess from which a port 39 leads
to the relief chamber proper 40. The outer end of this chamber is closed by
the plunger 41 having the packing 42 secured at its edges to the chamber, and
this plunger is normally forced inwardly as far as its outer enlarged portion
will permit, by means of a spiral spring 43 surrounding the external portion of
the stem 44 of the plunger, and bearing against a ring thereon, and an outer
plate 45 held by bolts 46. The power of this spring may be adjusted by suitable
nuts 47 which surround the stein and bear upon the plate.
At its inner cnd the relief chamber communicates by a series of ports 48
with a valve chamber 49 containing the outwardly seating valve 50, and from
this valve chamber leads the inlet port 19 to the space below the plunger 3.
The operation is as follows: The chamber below the cylinder plunger 3, as
well as the various passages and the relief chamber, being filled with oil, the
parts are normally maintained in the position shown in Figs. 1 and 3, in which
the wedge block 12 is held up against the pressure by the wedges 11 which in
their turn are held in their inward position by the engagement of their inclined
faces 10 with the inclined faces 9 of the plunger 3 and this again is held in its
protruded position by the confined liquid in the space behind the plunger.
When however the pressure on the rolls and consequently on the bearing 2 and
wedge block 12 exceeds a predetermined limit the corresponding pressure to

page_text: which the liquid behind the plunger is subjected will force open the valve 24
against the pressure exercised by the lever 33 so that the liquid can flow through
the ports 39 into the relief chamber 40, forcing back the yielding plunger 41
therein. The plunger 3 can now therefore yield to the inward pressure exercised
thereon by the action of the inclines 10 of the wedges 11 on its inclines 9 and
consequently the wedges 11 can give way to the outward pressure exerted thereon
by the wedge block 12 which will now move inwards relatively to the bearing
block 2 in yielding to the pressure exercised on the roll and the parts will
assume the relative positions shown in Fig. 2 in which consequently the roll
will be relieved of the excessive pressure, Laving been enabled to give way to
the extent to which 2 and 12 have moved toward each other.
In being forced outward as described, the wedges 11 will have compressed
the springs 15, so that as soon as the excessive pressure is relieved as described
the springs will force the sliding wedges back to their original position and the
spring 43 will force in its plunger, thus driving the oil out of the relief chamber
and back into the cylinder. The plunger 3 is thus forced outward in the
cylinder and the parts again assume their original position.
In Figs. 4 and 5, I show another form of my device whorein the wedge
system is within the bearing and the cylinder is supported at its end, the liquid
flowing from one side of the piston to the other side as this piston moves in
the cylinder. In this form, 51 is the bearing block having a vertically sliding
block 52 against which the ordinary adjusting screw 53 presses. Within the
bearing the block 52 is provided with an inclined face which fits upon the
inclined face of a wedge 54 which is arranged to move horizontally, and the
stem 55 of which projects through the bearing block and is secured to the
piston 56 of the hydraulic cylinder 57. A series of ports 58 extend through the
piston, these being normally closed by the spring-pressed inwardly-seating
valve 59. 60 is the outlet port which leads to a valve chamber containing a
valve 61 which closes this port and is provided with a protruding stem pivoted to
a lever 62 fulcrumed at 63 and acted upon by the stem 64 which is provided with
a spring 65 and adjusting wheel-nut. 66 as in the first arrangement. From the
valve chamber a port 67 leads to the other side of the piston, and within the
cylinder upon this side is provided a spring-pressed ring 68 which is suitably
packed as shown.
The operation of this construction will be substantially the same as above
described, except that the oil is forced from one side of the piston to a chamber
which is within the cylinder upon the other side of the piston, instead of being
a separate chamber, independent of the cylinder. The springs 69 act to force
the piston 56 back to its original position as soon as the excessive pressure is
זי
removed.
The advantages of my invention will be apparent to those skilled in the art,
since the danger of injury and breakage of the rolls consequent upon excessive
pressure is done away with, and the rolls automatically released when the pres-
sure reaches a certain limit. The system acts as a solid block in the ordinary
operation of rolling, and its yielding action comes into play only when there is
excess of pressure. The wedges are found to be of great advantage in con-
nection with the cylinder, as they hold the parts in normal position until the
moment that the pressure reaches the limit.
Many variations may be made in the form and arrangement of the cylinder
and other parts, without departing from my invention.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what
I claim is:
1. An automatic release device for rolls consisting of a bearing block with a
chamber containing a piston or plunger which is supported by a confined body.
of liquid against the normal pressure to which the rolls are subjected, but which,

page_text: on the occurrence of excessive pressure, will give way in forcing the said liquid
through a passage closed by a loaded valve, into a relief chamber, thereby reliev-
ing the rolls of the excessive pressure, substantially as described.
2. An automatic release device for rolls consisting of the combination of a
bearing block containing a cylinder and plunger or piston a relief chamber
communicating with the cylinder by ports closed by a loaded valve, a spring
pressed plunger operating in the relief chamber substantially as herein described.
3. An automatic release device for rolls consisting of a bearing block 2 inter-
posed between the roll and its regulating screw, in which bearing block is a
cylinder and a piston held by confined liquid against the pressure exerted on
the roll, these parts being so arranged in connection with a relief chamber com-
municating with the cylinder by ports that are closed by a loaded valve that
when a certain pressure on the rolls is exceeded, the liquid will force open the
valve and will flow into the relief chamber so that the piston can yield to the
excessive pressure, substantially as described.
4. In an automatic release dovice such as is referred to in the preceding
claims the combination with the bearing block 2 of a piston 3 working in a
cylindrical cavity and held in an outward position by confined liquid, wedges 11,
held in an inward position by inclines 9 on the piston engaging with inclines 10
on the wedges, and a wedge block 12, bearing upon the wedges 11 and subject
to the pressure of the adjusting screw of the rolls, the confined liquid behind
the piston being forced past a loaded valve 24 into a relief chamber 40 when a
cortain pressure on the rolls is exceeded substantially as described with reference
to Figs. 1 to 3.
5. In an automatic release device for rolls such as is referred to in the pre-
ceding claims the combination with the wedges 11 of springs 15 which force
the wedges back into their original position when the excessive pressure is
relieved, while at the same time a plunger 41 in the relief chamber is caused
by a spring 43 to force the liquid past a valve 49 back into the space behind
the piston 3 again, so as to force this outwards substantially as described with
reference to Figs. 1 to 3.
6. In an automatic release device for rolls such as referred to in the first
claim, the modification wherein the bearing block 51 contains an abutment
block 52 against which the adjusting screw presses and which rests with an
inclined face upon a wedge 54 connected to a piston 56 in a chambor 57, so that
on the occurrence of excessive pressure, this in being transferred by wedge 54
and piston 56, to, the liquid behind the latter, will force open the loaded valve 61
and will flow through port 67 into the relief chamber on the front side of
piston 56 and this in giving way to the pressure will allow of the inward
motion of the abutment piece 52, substantially as described with reference to
Figs. 4 and 5.
7. In an automatic release device for rolls such as is referred to in Claims, 1
and 5 the use, in the relief chamber in front of piston 56 of the annular spring
pressed piston 68 which, after the excessive pressure has been relieved will force
liquid in front of piston 56 through ports 58 and valve 59 back into the space
behind the piston substantially as described with reference to Figs. 4 and 5.
8. An automatic release device for rolls combined and operating as heroin
described with reference to Figs 1 to 3 of the drawings.
9. An automatic release device for rolls combined and operating as herein
described with reference to Figs. 4 and 5 of the drawings.
Dated this 4th day of June 1899.
ABEL & IMRAY,
Agents for the Applicant.