US 1677796 A
Description (OCR text may contain errors)
July 17, 1928.
R. D. PARKS YIELDABLE SUPPORT WITNESSES 5W Q Patented July 1.7, i928.
ROLAND DANE PARKS, 0F LAKE LINDEN, MICHIGAN.
Application led. February 18, 1926. Serial No. 89,124.
The device of the present invention while capable of a wide field of utility, is pri marily designed'for withstanding subsidence pressures in subterranean mining operations.
An object of the invention is to provide a. metal supportl or column adapted to take the place of the supporting timbers usually employed.
A further object of the invention is to provide a yielding support of this character embodying a yieldable or strainable element which becomes distorted under excessive pressures without distorting or twisting the main body of the column ory support.
A further object of the invention is to provide a device of the class described which will be of rugged, durable, practical con struction, which will be highly `efiicient and capable of repeated use, and which may be manufactured with comparative economy.
In carrying out the invention I prefer to employ a plurality of metallic members capable of a relative sliding action when an intermediate yielding member is strained by pressures on the relatively movable members.
Preferably the strainable element is capableV of ready removal and ,replacement so that undue pressures on the column can result in rendering useless onlyl the strainable element without impairing the further usefulness, or in any Way injuring the telescoping or relatively sliding members.
With the above noted and other objects in view, the invention consists in certain novel features of construction and combinations and arrangements of parts, as will be more fully hereinafter set forth and pointed out in the claims. The invention may be more fully understood from thev following description in connection with the accompanying drawings, wherein-` Fig. 1 is a broken view Vin front elevation of a supporting column embodying the invention.
Fig. 2 is a view in longitudinal section therethroughy on the line 2 2 of Fig. 1.
Fig.l3 is a view in transverse section on the line 3-3 of Fig. 1. Y
Fig. 4 is a perspective view of the strainable element.
Figs. 5 and 6 are side elevational views of thecutting implements. V
Fig. 7 is an enlarged edge view ofthe element shown in Fig. 4.
The problems involved in withstanding the subsidence pressures in subterranean mining operations are too well recognizedto by a support of 'ayieldable nature which I-Ience, the time kelement `is vital and can be furnished only will give underV excessive loadings, thereby allowing a natural arch to form and carry the greater portion of the subsidence pressure. Relatively non-yielding metallic supports, as they have heretoforev been installed with rigidity and strength as the objective become hopelessly deformed and vtwisted,blocl\. the underground passageways,
and are difficult to remove after distortion.
In accordance with the present invention,
I provide a yieldable metallic column or strut in which the distortion caused by subsidence pressures acts to telescope the column without distorting any part thereof, except a strainable element which mayI be readily removed and replaced.i
In thev accompanying ldrawings I have used the reference numeral 10 to designate an I-beam which serves as the base of the column. A pair of oppositely facing channel bars 11 are secured together in back toV back relationship, the flanges 11a ofthe channels being accommodated between the flanges or heads 1()a of the Ibeam. It will be noted that the channel members 11 are vspaced apart for disposition upon the opposite sides of the I-beam. Preferablythe upper ends of both channel members 11 are bolted to a spacer plate 12, and the upper portion of the I-beam 10 which is received between the channel members may be supplemented by spacer plates 13, so that the channel members have a sliding fitron the I-beam. y
The-channel lmembers are provided with 'slots 14 and 15'` aligned respectively with slots 16 and 17 in the I-beam. Bolts 18 'pass through the aligned slots 14, 16 and bolts 19 pass through the aligned slots 15, 17, guide the relative sliding movement of the channel members and the I-beam. It will be noted that the slots 14 are relatively short, and the slots 16V relatively long, and also the slots 15 are relatively long, while the slots 17 are relatively short. However, the effective relan tive sliding permitted by each set of slots is the same. By forming the channel members and the I-beam each with a set of short slots,
and a set of long slots, l preservethe maxi-v able element is in thenature of a plate 2O of soft metal or ymetallic alloy which is interposed'between the top of the '1l-beam 10 and a set of ltransversely mounted cutting tools 21 supported adjacent thereto by the upper ends of the channel members 11. It will be noted that the yieldable or strainable member 20 isv formed with a plurality of grooves 22 eX- tending longitudinally thereof to provide relatively lthin weakened portions 23 in the path 'of the cutting tools.
lvVlien the Vcolumn has been setup in a tunnel, and subsidence'pressures become great i enough to overcome the friction between members 10 and 11, plus the resistance offered by the ultimate. strength of the metal in the path of the cutting tools, there will be a relative sliding movement or telcscoping action of the members 10 and '11. Cutting tools 21 pass downwardly through the weakened portions 23 of the strainable element 20, cuttingthrough these portions and cutting or extruding the metal therefrom. Slots 25 are provided in the channel bars for the escape of metal forced outwardly by the cutting tools.
. From the foregoing description it will be evident that l have provided for considerable yielding of thecolumn without injury to any .portion thereof, except the member 20, so
that there is no danger of distorting the body of the column. Byidisassembling the sliding elements of the column, the strained. member 20 may be readily removed and replaced and the column reused. y
l have shown a strainableeleinent sub]eet Ato distortion under compression,rbut it will be obvious that this element might be arranged for distortion when the column is erted on relatively rotatingmembers, and
that it also mightbe distortedfunder shearing strains or stresses.
lt will also be obvious that various types of supports embodying'the principle of the present invention may prove useful in other lfields rthan underground mining operations.
ln fact, devices embodying the invention are suitable "for use wherever yielding struts, trusses or braces are desirable. f
Various changes and alterations might be made in the general form and arrangement or" parts described, without 'departingfrom the invention. Hence I do not wish to limit myselfto the details set forth,'but sha-ll consider myself at Aliberty to'make such changes and alterations 'as fairly fall within `the spirit and scope of the appended claims. A
,l claimy 1. A support of the class describedincluding an I-beain, spaced 'oppositely facing channel members straddling the I-beamjand mounted for limited slidingmovement relative thereto, a metallic element adapted to be f.
strained, vnormally blockingsliding move members straddling thej'Ib'eam anel'having.
limited sliding movement relative 'thereto,a soft metallic pl'ate'between thel channel members opposing-'sliding movementoff the 'channel members relative to the *Iebeann and `eutting elements I'associated with the channel members for strainingthe soft Imetal plate to permit such sliding movement;
. 3.' In a support 'of the class described, an I-beam, oppositely facing spaced channel members straddling the I-beam and :having limited sliding movement relative thereto, a
soft metallicnplate between the `channel mem-V bers opposing'sliding movement-of the .channel members relative tothe I-beam,'an'd cutting elements associated with the ychannel members for straining` the .soft metalplate'to permit such sliding "movement,y said ysoft metal platev being formed with weakened portions in thepathA of movement of `said eut'- ting elements. p K
QA device of vthe class vdescribed in claim 2, and wherein the channel membersfand I- beam are formedwith aligned slots, 'and bolts in said slots guide the 'sliding movement'of the members.
ROLAND DANE lPaints.