US1664525A - Pit cover - Google Patents

Description

J. H. OWENS April 3, 1928.

PIT COVER ist'. 21 1927 Filed Se Patented Apr.` 3, 1928.

.Unirse Asm y .JOHN-,HENRY OWENS, or Enorm, ILLIVNoIs *rrr Covina. n

Application `Med Asc :ptember 21, 1927. Serial No. 220,983.'

The main objects Iof Vthis invention are to .provide an improved 'form `'of `cover' V'which is yparticularly Yadapted for use 'infconnection vtywith pits; to `provide fimproved means l"for hinging and anchoring the cover tothe walls of the pit; to `provide improvedmeans `in the vmouth of the pit 'for supporting #the cover.; :and to providesupporting fmeans of-iv this kind which lare'removable to 'permit ready access yto vfthe pit whenf the lcover is open.

tion is shown in Ithe :accompanying vdrawing,

" vwherein Figure *1 Yi-saA planofazpit 'and cover to which this linventionis .-applied; part fof one f of fthe fcover-.sections beingbroken away.

Fig. 3 is a transverse section, taken onthe line3-3fof Fig. i1.

Fig. 4 is a detail in seetiomtaken ion'the.

line H of Fiv. 1'; the dotted outline representing fa `door sectional. in..partly open position.

Manholes heretofore in use by public utilities in connection with gas and water mains, and other underground service lines, consisted of pits of considerable size having roofs provided with contracted openings through which the workmen passed in entering and leaving the pit. Such pits were made suiiiciently deep to enable the workmen to stand erect in them. Due -to the large dimensions of those pits, a large amount of concrete or other building material was necessary in constructing the walls and roof, which made the construction of a pit very costly.

The deep pits heretofore in use were objectionable also from thestandpoint of sanitation, because the pit iioor was frequently located below the level of the street sewer, making it impossible to drain the waste ma terial, which usually enters street pits.

The deep type of pit heretofore in use in connection with gas mains has resulted in the asphyxiation of many workmen who, when overcome by escaping gas, were unable to climb out of the pit through the idly secured to the cover sections 15 and 16, vare hinge members 17, which are connected contracted opening in the roof.

The aforementioned objections to the pits heretofore in use have been cured by the im- An illustrative Iembedin'ient rof v`this invenproved p'itsto which this invention is vapfplied. In the embodiment herein shown",

invention isapplied to a comparatively avoid *.then'e'cessity of the objectionableroof :constructions*heretoforeiin use.. The cover isisupported by an kimproved beam structure which is removable to permit ready access toftheipitwhen the cover is open. Y'

shallowfopen pit having an improved form vofcover whichispans the entire .pit so as to In'fthe formV shown, the publie utility c manholetowhich this invention issapplied comprisesan openy governorxpit 1 havmgaa pluralityfof,removable beams 2 spanning. its

`openxendffor :supporting a lhinged cover 3;

' The 'pitizispreferablymade of 'concrete and comprises a bottom ltand upright side walls and -endf-walls 6. The bottom .4 is

provided 'with fthe ycustomary drainv 7,.,

Formed inthe'uppened'geszofthe walls 5,@are

recesses'l() providing seats for the side edges of the cover 3.

Formed in the end walls 6, adjacent the upper edges thereof, are recesses 11, having liners 12 forming seats for the removable beams 2. The liners 12 are .preferably sheet metal and comprise side plates 13, which are welded or otherwise secured to base plates 14 anchored'in the concrete walls. f l The' beams 2 may be of any form but are `preferablystructural steel I-beams of suli cient length to span the pit so as to be adapted to rest in the liners 12. Three beams are shown in the drawing, but any desired number may be used. One of the beams is arranged so as to support substantially the center of the cover and the other beams are arranged on opposite sides of the center beam.

In` the form shown, the cover 8 comprises two sections 15 which are hinged to one of the end Walls 6 and two other sections 16 which are hingedv to the opposite end wall. These cover sections 15 and 16 are preferably metal plates of suflicient strength to bear the street tratlic which passes over them. Riganchors 19 embedded in the walls 6. The upper edges of the end walls 6 are preferably recessed so as to oermit the hinges and the cover sections to 11e iush with the rim of the p1t.

Mounted on the lower faces of the sections 15 are depending brackets 20, which support locking bolts 21, which are slidable into engagement with the lower face of the center beam 2 for locking the cover.V Formedwin the cover sections 15, are apertures 22, through which a tool, not shown, may be inserted for engagement with lugs 23 on the.

locking bolts 21, whereby the bolts may be shifted into and out of locking position.

The cover sections 16 are provided with tongues'24adapted to engage the lower faces of the sections 15 to secure the sections 16 against opening while the sections 15 are closed. f

With this improved form and arrangement of parts, the pit may be made comparatively shallow so that workmen standing in the pit may have their heads above ground, thereby eliminating the danger of asphyxiation. To enter the pit, the cover sections 15 are unlocked and openedbefore opening the sections 16. After the cover is opened, the beams 2 are lifted fromtheir seats so as to leave the entire top vof the pit open.

Although but one specific embodiment of this invention has been herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the 2. A public utility manhole comprising an open pit having upright concrete walls providedwith recesses in the upper edges thereof, structural steel beamsremovablyA seated in said recesses and spanningV the'pit,a.

pair of hinge pins anchored to respectively opposite walls of the pit, and aplurality of cover sections connected to said hinge pins and loosely supported on said beams. j

3. A public utility manhole comprising an open pit having upright concrete'walls provided with recesses in the upper edges thereof, structural steel beams removably seated inksaid recesses and spanning the pit, a' pair of hinge pins anchoredto respectively opposite wallsof the pit,a plurality of cover sections connectedl to said hinge pins andv loosely supported on said beams, and-means for locking sald cover sections to one of saidy beams. f

Signed at Aurora, Illinois, this 16th day of -September, 1927.

- JOHNA HENRY OWENS.V

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