Improvements in and relating to Mine Gates.
Year: 1898

page_text: Date of Application, 2nd Aug., 1898-Accepted, 1st Oct., 1898
COMPLETE SPECIFICATION.
Improvements in and relating to Mine Gates.
I, NEWTON KIBLER BOWMAN, a Citizen of the United States of America, residing
at 5, North Fulton Street, in the Town of North Lawrence, County of Stark and
State of Ohio, United States of America, Gentleman, do hereby declare the nature
of this invention, and in what manner the same is to be performed, to be particu-
larly described and ascertained in and by the following statement:-
This invention relates to improvements in mine gutes or trap doors, and consists
of certain novel features of construction, combination and arrangement of parts;
which will be hereinafter more fully described and particularly pointed out in
the appended claims.
The objects of the invention are, first, to provide a gate of this character which
is simple, durable and inexpensive in construction and adapted to be operated
automatically under the weight of a car or pedestrian; second, to provide à light,
flexible rolling or folding gate curtain in lieu of the ordinary heavy and cumber-
some trap door, by means of which all liability of serious injury to the draft
animals and persons passing through the gate-way is avoided in the event of the
curtain accidentally falling; third, to 'provide simple and efficient means for
opening the curtain and closing the same by gravity; and, finally, to simplify
and improve the construction and render more efficient the operation of this class
of gates generally.
I attain these objects by the mechanism illustrated in the accompanying
drawings, in which-
Figure 1 is a perspective view of a mine gate constructed in accordance with
my invention.
Figure 2 is a fragmentary end elevation thereof.
Figure 3 is a vertical longitudinal section, showing the position of the parts
when the gate is open.
Figure 4 is a vertical transverse section through the gate platform.
Figure 5 is an end elevational view, showing a modified form of gate curtain
and operating mechanism.
Figure 6 is a vertical, longitudinal section of same, showing the position of
the parts when the gate is open.
Figure 7 is a transverse section of the gate platform and an elevational view
of the gate.
Figure 8 is a broken detail view of the gate curtain and sectional elevation
of one of the guide posts.
Figure 9 is a central vertical section through the gate frame, and shows a
modified form of folding gate curtain.
Figure 10 is a central vertical section of same, showing the gate curtain
folded or in open position.
Figure 11 is an enlarged detail sectional view of the parts shown in Figure 10.
Figure 12 is a sectional view of a portion of the gate detached;
Figure 13 is a side view of one of the quadrant levers.

page_text: Figure 14 is a front and side view of the platform adjusting device.
Referring now more particularly to Figures 1 to 4 inclusive of the drawings,
1 represents the gate platform frame comprising two longitudinal side sills 2
connected at their ends and center by transverse braces 3.
4 represents vertical posts or standards rising from the sills or center transverse
brace and connected at their upper ends by a transverse lintel rail or bar 5,
and 8-9 represent inclined tilting platforms mounted on the said frame and
carrying track rails 91 secured to and supported by cross-ties 10. The deck-
flooring 12 of the platforms is laid on said cross-ties, and said platforms form two
inclined planes, having their highest portions at the center of the platform frame
in line with the standards 4 and having their inner ends suitably connected to
rise and fall at the center in unison.
4 represents the gate posts which are arranged on the inner side of the
standards 4 and parallel therewith and connected with the center transverse
brace 3 and lintel or cross-bar 5. These posts form in connection with the said
standards and lintel, a gate frame, and are provided on their inner sides with.
vertical guide grooves 6.
7 represents truss rods, two of which are provided on each platform, one at
each side and extending longitudinally thereof. Each truss consists of two
sections having their inner ends united by a swivel or turn-buckle 7 and their
outer ends connected to eye-bolts 7b on the cross-ties 10, and the central portion
of each truss is supported by a brace or guide 7 on the center cross-tic, as shown..
These trusses are adapted to prevent the rails and the platform deck from bending
or sagging unduly under the weight of heavily-loaded cars.
The gate 13 is in the form of a curtain preferably made of heavy ducking,
canvas or some other suitable water-proof material. This curtain is .connected
with and adapted to wind upon a roller 18 having stub shafts 19 journaled in
bearings 16 on the posts 4 and carrying sprocket pinions 20. The gate curtain
is stiffened by transverse cleats or strips 13" to resist air pressure and is provided
at the lower end thereof with a sleeve or pocket 20 for the reception of a com-
paratively heavy transverse bar 14, the ends of which are fitted to slide in the
guide grooves 6. The lower edge of said bar is recessed at 15 and the sleeve is
made to conform thereto, so that the lower end of the curtain may fit over the
rails and rest upon the platforms.
The strips 13 stiffen the curtain sufficiently to prevent it from bulging at the
center, while permitting it to readily roll on the roller 18, while the transverse
bar 14 holds the lower end of the curtain firmly and maintains it in close contact
with the platforms.
16 represents winding shafts located between the posts or standards 4 4 at
each side of the gateway and mounted in bearings 16b thereon. Each of said
shafts carries a grooved pulley 21 and two sprocket wheels 22-23 of different
sizes, one on each side of said pulley, and chains 24 connect the sprocket wheels 22
with the sprocket pinions 20 on the roller shaft 19. 25 represent lifting chains
having one end connected with eye bolts 24 on the platform 8 and the other
end made fast to the sprocket wheels 23, and 26 represent cords, ropes or cables
made fast to the pulleys 21 and carrying counterbalancing weights 27 formed at
opposite sides with flanges 28 traversing guide grooves 28° on the inner faces of
the posts 4 and 4*.
29 represents a flap secured to and depending from the lintel 5.and adapted to
close the opening between said lintel and the curtain roller.
The operation of the gate thus constructed is as follows:-
When a person walks upon one of the platforms, the platform 9 for instance,
or a car rolls upon the rails thereon, the weight of said person or car will depress
and cause both platforms to tilt or sag down at the center to a horizontal position
until the cross-ties rest upon the stops 29. This will draw on the chains 25 which
will operate the shafts 16", which in turn will revolve the roller 18 through the

page_text: medium of the eprockets 20 and 22 and chains 24, and draw up the counter-
balancing weights 27. The gate curtain will thus be caused to wind up on the
roller 18 and open the gate-way, and will remain in this position until said person
or car has passed over the platform 8, when the gate curtain will be unwound
and closed and the platforms restored to their normal position by the combined
weight of the platforms themselves, the transverse bar 14 and counterbalancing
weights 27.
In the embodiment of my invention disclosed in Figures 5 to 14 inclusive, I
employ a folding gate curtain and a modified form of mechanism for operating
the same.
The numeral 13b represents the gate curtain in this instance, which is
secured at its upper end to the lintel 5 and provided at its lower end, like the
rolling curtain 13, with a sleeve or pocket in which is enclosed a bar 14" formed
at its opposite ends with reduced stems 17 provided with terminal eyes 17*. The
posts 4 are formed on their inner sides with guide grooves 6* merging into
narrower guide slots 6 which open through the outer sides of the post, as shown
in Figure 8. The side edges of the curtain slide in the grooves 6, while the
stems of the bar project through the slots 6b into the space between the posts 4-4.
The curtain is stiffened to resist air pressure by batten rods 30 secured thereto,
and the ends of these rods also project through the guide slots 6b and are formed
with eyes 30 as shown. 31 represent cords or cables secured at one end to the
eyes 17 of the bar 14* and extending through the eyes of the batten rods and
passed over grooved pulleys.32 carried by shafts 33 mounted to revolve in bearings
on the standards and posts 4-1. The opposite ends of the cords or cables are
attached to the arms 35 of quadrant levers 34. These quadrant levers are
arranged at opposite sides of the gate, each being rigidly mounted upon a shaft 36
having bearing in the adjoining standard and gate posts at that side. A chain 37
connects each quadrant lever with the platform section 8.
The operation of the gate thus constructed is as follows:
When a person walks upon one of the platforms, the platform 9 for instance,
or a car rolls upon the rails thereon, the weight of said person or car will depress
and cause both platforms to tilt or sag down at the center to a horizontal position.
This will draw on the chains 37, which will move the quadrant levers from the
position shown in Figure 5 to the position shown in Figure 6.
The cords or cables 31 being secured to the lever arms 35, will move in accord-
ance therewith and raise the lower end of the curtain, causing it to fold in the
manner shown in Figure 6 and open the gateway. The gate curtain will remain
open until the person or car passes over the platform section 8, whereupon the
gate will be caused to unfold and close the gateway by the weight of the bar 14*
and at the same time the platform sections will be restored to their normal
position.
Automatic pivoted dogs 38 are provided on each gate post 4ª to engage the
bar 14 and prevent the curtain from sagging down until the full weight of the
car or person is removed from the platform. These dogs, which are shown in
Figures 5 and 10 for clearness of illustration, are each formed with a hook a and
an arm b carrying a pivoted guide-block c which moves in a horizontal slot d in
the gate post. Each dog is pivoted at the intersection of its hook and arm by a
pin or bolt e. The dog is actuated to engage and release the curtain by a pivoted
bell-crank lever f having one of its arms adapted to engage the extended pivot
pin e of the block c and its other arm jointed to a rod g movable in guides on the
post 4. The lower end of this rod is adapted to engage a trip device of suitable
construction on the platform section 9, so that when the said platform section is
depressed or the curtain folded, the rod will be moved to cause the block c to
insert itself under the bar 14*, and when the platform section raises, to perform
the reverse operation.
C
The mechanism for adjusting and maintaining the gate platform sections in
proper operative position is shown in detail in Figure 14, and comprises a

page_text: bracket 39 secured to each standard 4 and formed with a headed arm 39ª which
operates in the longitudinal slot of a tension bar 40 and serves as a guide therefor.
The bar 40 is formed with stop pieces 41-42 at its upper and lower ends and
is encompassed by a stiff spiral spring 43 which abuts against the stop 41 and
heads on the bracket arm 39". An adjusting bolt 44 connects the bar 40 with an
eye bolt 45 swiveled to an eye 46 fixed in the platform, and a nut 47 on the
shank of the bolt 45 couples said parts together.
It will be understood that by adjusting this nut the tension of the spring may.
be increased or diminished and the pull on the platform sections thereby regu-
lated. Thus, if the platform sections become choked by coal dust or laden by
reason of water-soaking or the accumulated deposit of mud or coal thereon, the
tension of the springs may be increased to prevent said sections from sagging
down.
In the further embodiment of my invention shown in Figures 9, 10 and 11,
the lower end of the gate curtain is secured to an angle stay-plate 48 connected
to the bar 14" by a bolt or rivet 49. Transverse slats 30 are secured to the
curtain at suitable distances apart from one another in such manner that the
flexible portion of the curtain between adjoining slats serves as a hinge to permit
the said slats to successively assume a vertical position and lap against one
another in folding the curtain, as clearly shown in Figures 10 and 11; when
folded, the slats extend parallel with the vertical web of the stay-plate 48 above
the bar 14. The said bar 14 is provided at each of its ends with an arm or
extension (not shown) which travels in the slot 6b of the posts 48, and to these
arms are attached flat tapes or bands 31° which pass over the flanged pulleys 32
and are secured to the arms of the quadrant levers and drawn upon in the same
manner as the cords 32 in Figures 5 to 8 inclusive.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
-
1. In a mine gate, the combination of a platform frame having a gate frame
mounted thereon, two inclined tilting platforms forming inclined planes having
their highest points at their inner ends and said ends being connected to rise and fall
in unison at the center of the platform, a flexible gravity-closing gate curtain,
and connections between one of said tilting platforms and the curtain, whereby
when either one of the sections is depressed the curtain will be caused to rise
and open, substantially as described.
2. In a mine gate, the combination, with a base frame, of a gate frame mounted
thereon, a rolling gate curtain carried by said latter frame, two inclined tilting
platforms connected at their inner ends to each other, and connections between
the said inner ends of the platforms and gate curtain to wind up the latter when
the platforms are depressed, substantially as described.
3. In a mine gate, the combination, with a base frame mounted thereon and
carrying a roller, a curtain connected with the roller and adapted to wind thereon,
two inclined tilting platforms, chain and sprocket gearing connections between
said platforms and curtain roller for revolving the latter when the inner ends of
the platforms are depressed, and counterbalancing weights for revolving said roller
in the reverse direction and restoring the parts to their normal positions, substan-
tially as described.
4. In a mine gate, the combination with a base, of two inclined depressible
platforms carrying track rails, cross ties connecting said rails, a deck flooring
laid on said cross ties, an adjustable truss rod extending longitudinally beneath
each rail, a support connected with the inner cross the of one platform and pro-
jecting under the inner cross tie of the other platform, a-gate curtain, and a
connection between the platforms and gate for operating said curtain, substan-
tially as described.
5. In a mine gate, the combination with a base support or frame, of the spaced,

page_text: parallel posts 4-4° rising therefrom, two inclined depressible platforms, a
roller 18 mounted in bearings on said posts 4 and carrying sprocket pinions 20,
winding shafts 16 mounted in bearings on the posts 4-4 and each carrying two
sprockets 22-23, chains 24 connecting the sprockets 22-20, chains 25 connecting
the sprockets 23 and one of said platforms, a gravity closing gate curtain con-
nected with said roller, and means auxiliary to the gate, for restoring the plat-
forms to their normal positions and assisting in effecting the closing of the gate,
substantially as and for the purpose set forth.
6. In a mine gate, the combination of a base frame comprising two longitudinal
side sills connected at each end by cross bars, posts projecting upward from
the centers of said sills, two inclined tilting platforms comprising track-rails
having their lower ends resting on said cross bars, cross ties carrying said rails,
and the end ties abutting against said cross-bars, adjustable truss rods extending
between the end cross ties on each platform beneath the rails, a rolling gate
curtain mounted on said posts, and a connection between the platforms and gate
for operating the latter, substantially as described.
7. In a mine gate, the combination of a base frame carrying the posts 4-4",
two inclined depressible platforms, a roller 18 mounted in bearings on said posts 4°
and carrying sprocket pinions 20, winding shafts 16 mounted in bearings on the
posts 44 and each carrying a grooved pulley 21 and two sprockets 22-23;
chains 24 connecting the sprockets 22-20, chains 25 connecting the sprockets 23
and one of said platforms, counterbalancing weights suspended from the pulleys 21
and provided with flanges traversing guide grooves in said posts, and a gate
curtain connected with said roller, substantially as described.
8. In mine gates, the combination with a tilting platform and a gate connected
therewith so as to be automatically operated thereby, of a spring actuated tension
device supporting the platform and adjustable to vary its resistance to the down-
ward tilting of said platform, substantially as described.
9. In mine gates, the combination with a tilting platform, and a gate adapted
to be operated thereby of an adjustable platform supporting device, comprising
a slotted bar, a bracket on the gate-post having an arm fitted in the slot of the
bar and forming a guide therefor, a spiral spring encompassing said bar and
bearing against the bracket arm, an eye-bolt connected with the platform, and
an adjusting bolt connecting said bar and eye-bolt and adapted to be adjusted to
vary the tension of the spring, substantially as described.
10. In mine gates, the combination of a tilting platform, a folding gate
curtain, and a connection between the platform and curtain whereby the tilting
of said platform will cause the curtain to fold, substantially as described.
11. In mine gates, the combination of a tilting platform, a folding gate
curtain, and a pivoted lever connected with the lower end of the curtain and
platform, and adapted to be operated by the tilting of said platform to cause the
curtain to fold and open the gateway, substantially as described.
12. In mine gates, the combination of a tilting platform, a folding gate
curtain, a tension device supporting the platform and adjustable to vary its resist-
ance to the downward tilting thereof, and a connection between the platform and
curtain whereby the tilting of said platform will cause the curtain to rise and
open, substantially as described.
13. In mine gates, the combination of tilting platforms, a folding, gravity.
closing gate curtain, a pair of pivoted levers, cords or cables connecting the
lower end of the curtain and free ends of the levers, and a connection between the
said levers and platform, substantially as described.
14. In mine gates, the combination of a frame carrying gate posts, tilting
platform sections mounted on said frame, a folding gravity closing gate curtain
secured at its upper end to said posts and provided with stiffening rods having
eyes, a pair of pivoted levers, cords or cables connecting the lower end of the
curtain and free end of the levers and extending through said eyes, and a con-

page_text: nection between each lever and one of said tilting platform sections, substantially
as described.
15. In mine gates, the combination of a frame carrying standards, gate posts
arranged parallel with said standards and formed with guide slots, two tilting
platform sections mounted on said frame, a folding gate curtain made fast at its
upper end and carrying at its lower end a gravity bar, stiffening rods secured to
said curtain and formed at their ends with eyes, a pair of quadrant levers pivoted
between the posts and standards and having arms, cords or cables connecting the
gravity bar at the lower end of the curtain with the free ends of said lever arms
and extending through the eyes of the stiffening rods, and a chain connecting
each quadrant lever with one of the platform sections, substantially as described.
Dated this Second day of August 1898.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.