Improvements in Ventilation Doors for Mines.
Year: 1896

page_text: Date of Application, 31st Mar., 1896-Accepted, 7th Nov., 1898
COMPLETE SPECIFICATION.
Improvements in Ventilation Doors for Mines.
I, JAMES O'BRIEN, of Evansville, in the County of Vanderburg, and State of
Indiana, Unitel States of America, Mechanic, do hereby declare the nature of
this invention 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 improvements in that class of mine doors which are
adapted to cut off or control air currents in the different portions or compartments
of a mine and such invention primarily has for its object to provide a door of this
character and operating means therefor which can be placed on curved as well as
straight portions of the track and in which the doors are automatically opened or
closed by the car as it reaches the doorway from either direction.
My invention also has for its object to provide a door of this character and
operating means therefor so arranged that the door can be opened or shut close to
the track rail and thereby reduce the danger of escape or waste of air under
the door to a minimum.
Furthermore, my invention has for its object to provide a car operated lever
mechanism for opening the door capable of use on curve I track sections and having
a re-enforce or trussing means which will serve to strengthen and hold the said
lever mechanism from being bent or unduly strained as the loaded car passes
thereover.
Again, my invention among other objects which will hereinafter appear has for
its object to provide a mine draft door and means for automatically opening and
closing the same of a simple and economical construction which can be readily
arranged for practical use and which will effectually serve for its intended
purposes.
The invention consists in the peculiar combination and novel arrangement of
parts such as will be first described in detail and then specifically pointed out
in the appended claims reference being had to the accompanying drawings in
which
Figure 1 is a perspective view of my improved mine trap door and operating
mechanism showing the same in their normal position. Figure 2 is a top plan view
of the same, the parts being in the position shown in Fig. 1.
Figure 3 is a top plan view of the door, showing the position of the opposite
members thereof as the car passes therethrough.
Figure 4 is a detail view of one of the lever-sustaining chairs hereinafter
referred to, and
Figure 5 is a transverse section taken on the line 5-5 of Fig. 2.
Referring to the accompanying drawing A indicates the door framing which is
disposed in the mine at the entry to which the door sections B B are hinged
in the manner clearly shown in Figs. 1 and 2 each section having a triangular
top pieces b, b, so that when the door sections are to a closed position they will
assume a V-shaped position, the pieces band b' closing the top; suitable pieces C, C,
being disposed between the back rails and to the outside thereof see Fig. 1.
The main object of my invention is to provide opening and closing devices for
the door which are capable of operating on a curved portion of the track and which
Two lever rails D and E are
in themselves are operated by the passing car.
provided, one E leading towards the entrance, which empty cars in passing over

page_text: serve to open the gates or doors, the other D coming towards the exit which the
loaded cars pass over, answering the saire purpose, the construction of the latter
lever mechanism being, however, the essential feature of my invention.
By referring now more particularly to Fig, 2 it will be observed the lever
mechanism D is disposed adjacent to a curved track section, and comprises a lever
rail D' curved parallel with rail, and having at its extremities right angle
extensions d' d2 which are pivoted in brackets d3 one of such extensions d' having
a weight F which serves to normally throw the lever rail at a point above the track
rail as clearly shown in Fig. 5, the member d2 being extended and connected
at d4 to a crank member g, of a rock bar G the purpose of which will presently
appear.
The lever rail also has a number of extensions H the number depending upon
the length of such rail which in practice may vary in length to about 12 feet.
Through the several extensions H as also through end extensions d' d 2 is passed a
truss rod I made preferaby of of an inch iron, the ends of which are threaded
as at it, to receive the adjusting and binding nuts as clearly shown. The
several extensions H are also pivotally joined to chair members J in turn pivoted
infixed brackets j, and formed with recess ends J¹ in which the truss rod is adapted
to rest when pressure is applied to the lever rail.
By connecting the said awitch rail at points between the ends of the chair
members by a supplemental pivotal connection which when pressure is applied to the
said rails assumes practically a single pivotal joint, provision is made which permits
the said rail to adjust itself the more easily at the different points and thereby
provide against a too great a strain at points intermediate its ends when the car
passes thereover. By constructing the lever rail over which the loaded car passes
in the manner stated, that is by trussing same and pivotally joining the same to the
brackets as shown, the said fever rail is sufficiently braced and strengthened to
stand the strain put upon it by the passing loaded car, without danger of its being
bent out of a proper alignment with the rail.
The lever rail E also has a short truss rod E¹ but has no chair connections
intermediate its ends, as such rail is held adjacent a track section nearly straight
such lever rail section E has an extension e which is connected at el to a crank
member g of the rock bar G. This rock bar is journaled at one side of the gate
or door in bearings g 2 on the cross ties and has an upwardly-extending arm G
which has a link connection with the door section B as most clearly shown in
Fig. 1 such bar G having a counterweight 94 to assist in keeping the said bar and
lever rails to their closed position.
Heretofore the main trouble to overcome in order to get a successful operating
mine trap door was the expense attendant upon placing the same, since perfectly
straight tracks only could be used. By my improvements the form of my lever
rail is such that it can be adapted to fit with almost any curvature of track section
in a manner at once substantial and removable.
The door sections B and B' have the ordinary toggle lever connections B 5 to
cause them to move in either direction synchronously.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a mine trap door operating mechanism as described, the combination with
the doors and a curved track section, of the door opening and closing rock bar
and a pivoted lever rail curved parallel with the curved track section, connections
joining such rail with the rock bar, and means for closing the doors after they are
opened as set forth.
2. In a mine trap door operating mechanism as described, a lever rail adapted
to be fitted to operate on a curved track section having pivotal connections at
their ends with the tie chairs and provided with re-enforce or truss irons
substantially as shown and described.

page_text: 3. In a mine trap door operating mechanism as described, a lever rail adapted
to be fitted to a curved track section having pivotal connections at the extremities
with the tie chairs, and similar connections between the said extremities having
supplemental pivot joints substantially as shown and described,
4. In a mine trap door operating mechanism as described, a lever rail having
pivotal connections at the extremities with the ties, and similar connections between
the said extremities having supplemental pivot joints, and a truss or re-enforcing
rod passed through the ends and intermediate connections having adjusting nuts
at the ends as set forth, and for the purposes described.
5. As an improvement in mine trap doors, the combination with a curved track
section and the double doors joined to operate simultaneously and the rock bar G
having an arm connected to one of the said doors and having crank ends and means
for holding the bar G to its normal position, to close the door, of lever rails
arranged at entrance and exit entries of the door, having pivotal connections with
the ties and having right angled extensions connected with the crank ends of the
bar G all arranged substantially as shown and for the purposes described.
6. As an improvement in a mine trap door operating mechanism substantially as
described the combination with the curved track section and the devices for
normally swinging the doors to a closed position, of the lever rail D, the brackets d'
said lever rail held in the brackets d³, and provided with extensions H, the fixed
brackets j, the chair members J, pivoted in the brackets j, and pivotally joined to
the extensions H, and the truss rods I passed throngh the several extensions H,
and d', and provided with adjusting nuts at the ends all arranged substantially as
shown and for the purposes described.
Dated this 21st dose of March 1906
BOULT & WADE,
Agents for the Applicant.