US1777763A - Centrifugal molding device - Google Patents

Centrifugal molding device Download PDF

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US1777763A
US1777763A US145568A US14556826A US1777763A US 1777763 A US1777763 A US 1777763A US 145568 A US145568 A US 145568A US 14556826 A US14556826 A US 14556826A US 1777763 A US1777763 A US 1777763A
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mold
shaft
bearing
poles
basin
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US145568A
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Page Justus F Ne
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B28WORKING CEMENT, CLAY, OR STONE
    • B28BSHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B21/00Methods or machines specially adapted for the production of tubular articles
    • B28B21/02Methods or machines specially adapted for the production of tubular articles by casting into moulds
    • B28B21/10Methods or machines specially adapted for the production of tubular articles by casting into moulds using compacting means
    • B28B21/22Methods or machines specially adapted for the production of tubular articles by casting into moulds using compacting means using rotatable mould or core parts
    • B28B21/30Centrifugal moulding
    • B28B21/305Moulding machines with vertical rotation axis

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  • This invention relates to an improved method of'forming concretepoles," orlposts; more particularly, forforming reinforced concrete poles for supporting electric street lighting systems,and ⁇ it isthe object ofthe invention to provide means for thernanufacture of poles and the like, whereby all. air pockets, ⁇ Water, bubbles or pipngsuareu eliminatedand a dense, ho1nogeneous,uniform ar- ⁇ *Q ticle Withafsmooth exterior ⁇ is produced. ,.5
  • Figure 3 is ⁇ a transverse, sectional view ⁇ through the mold.
  • ⁇ 'Ihejframe ⁇ comprises upper and lower bearings 5 and-6 -in which a shaft 7 Fixedonthe shaft betvveenfbearings 5 rotatablyinounted; the shaft being reduced in diameter near its lower end topro# vide aidoWnWardly facingshoulder 8 that ⁇ seats upon a thrust ⁇ bearing 9.
  • the upper end of shaft 7 is cupped to' form ⁇ a seat 16 for ahardened steel ball 17 which provides a universal bearingformounting the moldgcoaxialjwith the shaft by means of ⁇ cupped seat 18 in therbaseplate 19,7016 the mold; ⁇ vvhosesides are made up of aplu- ⁇ baseplate 19 and flanges 22, and serve" to rov et i tate the mold about its vertical axis; the up-v Vper end ofthe moldf beinglmaintained in a substantially true vertical" position 1 by means of a tubular top ournal 80, Tha-ving* a flange 31 securedby bolts ⁇ 32 totop flanges 23', and rotatively mounted in bearing 33 supported byk suitable cross members 34 that, in turn, arereinovably fastenedto a towerlke-struc ture (not shown) which is adapted to facilitate the Work of the operator.
  • Tubular journal 30 is made of sullicient length to project through a loose fitting cy lindrical aperture provided in the bottom of a discharge basin 36 removably supported by cross members 34.
  • a horizontally disposed, internallythreaded,annular disc 3? is screwed onto the 'threaded top of journal 30, Vafter discharge basin 36 is placed in position, the several parts functioning as hereinafter described.
  • the mold sections may be constructed to form poles of a wide variety of designs hav,- ing circular, hexagonal, fluted or other cross sectional shapes.
  • the 'mold here shown, for simplicity, has been made of circular cross section.
  • j If the 'poles are to contain vertical reinforcing bars 4l and spirals 42, as illustrated in Figures 2 and 3, these are assembled preferably as a unit by means of tie Wires 43, two or more sets of cross rods 44, Welded at their junction points 45, being used to position the reinforcement centrally in the mold.
  • a conduit pipe 46 to carry electric circuit Wires may also be located centrally of the mold by means of cross rods 44 as shown.
  • the 'reinforcement unit vand conduit are preferably placed Within the mold prior to securing ⁇ the mold sections together. Plugs or corks'47 are used to close the ends of the conduit until after the concrete is set.
  • the rotation of the'mold is preferably opposite to the direction traced in following down the spiralling'of'the reinforcement, as indicated by the arrow across the near side of shaft 7 for the spiral reinforcing illustrated in Figure l.
  • ThisV has been found to facilitate the process in the elimination of voids, b y Working the concrete doivnu'ard as it enters the mold.
  • the mold and apparatus are assembled as illustrated in Figure l and the mold rotated at a suitable speed by means of an electric motor or other motive power (not shown), While yfluid concrete, or other material, is poured slowly into the mold.
  • Means are provided Whereby the operator may adjust the speed of rotation of the mold to such value that the solids build up Within the mold in the form of a basin resembling a vertical paraboloid into which the air bubbles and excess Water, or suds, are squeezed as the solids are centrifuged against the Walls and settle at the center of the mold. Much care is taken during the pouring process to prevent the trapping of air or .excess Water by too rapidly pouring in the material; and the para bolo'idal basin is maintained by proper speed control for the various diameters.
  • Tubular journal v30 is then taken off by removing bolts 32 and the concrete smoothed off' level With flanges 23, thus ⁇ exposing the yend of conduit pipe 46. After th'e material has sufficiently set, bolts 24 and 25 are removed and the mold sections stripped from ⁇ the finished article.
  • a device of the character described comprisingan upright mold adapted to be filled through its upper end, a universal bearing ⁇ concentrically on the upper end of said shaft through the intermediacy of a universal bearing, an, alinement bearing ⁇ for the upper end l ofthe mold andmeans fixed to and extending ⁇ 1 laterally fromthe shaft and operatively connec/ted to rotate the mold with the shaft.
  • a device of the character described comprising a vertical, revolubly driven shaft, an
  • fA device of the, character described loom- ;prisingia verticalrevolubly drivenf ⁇ shaft, an i upright mold having ⁇ its fbasefcentra'lly sup;- ported on the upper end of said ,shaft through the intermediacy oflaf universal bearing, a
  • an upright mold having ⁇ its/base. centrally i sui'ap'orted[onA the upperf end of said shaft through the intermediacy of auniversal bearing, a torque arm fixed tothe shaft, ⁇ pins extended upwardly from the arm and engaging the base of the mold to cause it to rotate with the shaft.
  • an upper frame structure a
  • a device of the character described comprising a vertical.l revolubly driven shaft
  • anupright mold having itsbase centrally supported on the upper yend of said shaft through'the intermediacy of a universal bearing, a torquearm fixed to the shaft, pinsextended upwardly ⁇ from thearm and engagwith the shaft, an upper frame structure, a discharge basin mounted by said upper frame structure and having a cylindrical aperture forming an alinement bearing, a tubular journal mounted on the ⁇ upperend of the mold and extending rotatably through said alinement bearing and adapted to receive the l material therethroughfor filling ⁇ the mold,
  • poles of the character described which consists of mounting a mold vertically for axial rotation, preiparing a mixture of concrete rhaving a high Water-cement ratio to render the mixture excessively Huid, pouring the mixture into the -mold While the latter is rotated at such speed ⁇ as 'to cause the material to buildup within 4the 'mold in the form of a paraboloidal basin Ain which the excessive Water squeezed from the material will be carried upwardly and finally spilled 'from the top of the mold.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)

Description

Oct. 7, 1930.' 1. F. NE-PAGE CENTRIFUGAL MQLDING vDEVICE Filed Nov. l, 1926 Il Inutili!!! In!! vlfuilllfrl |14 .i ...u
v INVENTOR Ji/5 T05 F. NEP/i615 Y ATTORNEY Patented Oct, 7, 1,930 7 AUNI'PISD VSTA'll-:S
vPA-TE NT i OFF-1C i lJns'rns nNnrAGE, or SEATTLE, Wasirnveroir CENTRIFUGALMOLDING DEVICE Appiicationmea November 1, 1926. serial ramasse.
This invention relates to an improved method of'forming concretepoles," orlposts; more particularly, forforming reinforced concrete poles for supporting electric street lighting systems,and `it isthe object ofthe invention to provide means for thernanufacture of poles and the like, whereby all. air pockets,` Water, bubbles or pipngsuareu eliminatedand a dense, ho1nogeneous,uniform ar- `*Q ticle Withafsmooth exterior `is produced. ,.5
` Heretofore, ,Where the tamping and `,other methods have been employed,"it has been practi'cally` impossible to produce` poles vWhich f5 Were freefromsurfacefand interior 'defects a i' caused'bfy voids. Due to the fact that, ina
moldof considerable length asis requiredY for the formation of poles of the` present character `and especi'allyjvvhencontaining reinforcingrods, or pipes forthe passage of circuit Wires, tamping cannot be done with any degree of success, and consequently, excessive water and bubbles cannot be eliminated and 4 produce the objectionable voids referred to.
posed vertically, meaning any substantially upright position for carrying outtheprocess and rotated at such speed that when concrete or other concretious materiahis poured into the topof the mold at a slow rate, the excess Water and air Will be squeezed to the center and topfas the relatively heavy `material builds up inthe mold and is .centrifuged against the 1Walls thus forming a basinlike depressioniinWhichthe Water and airA bubbles,` or `suds`r arel Carriedlupwardly llylitil spilled vfrom the top of the-incid.v Y
i In carrying" outthe process, I haveiprovid-` type i Aas illustrated Y in, dravvinggwhereinf' y M ,y i, f Fsf ifs a fsdfe @levaitieri ef a' molding mahilefsutableferthis rlirposeth I ecwmreeying F,i,g, ure2 is a vertical center section ofthe removable top journaland upper `end of the mold,=shovving a conduit pipe, reinforcing reds, etcQ, and:` illustrating. the manner-in se whichtheformative-material; builds with# .The presentmethod contemplates" the use of a centrifugal molding apparatus disV ledaf suitable mechanism of the Vcentrifugal in the mold to squeee the Water and bubbles to thecenter. 1
Figure 3 is` a transverse, sectional view` through the mold.
Referringmore indetail to ,the drawingsl" 1` designates a frame structure provided,
at its base, With laterally turnedflanges 2 for receiving anchor bolts wvvherebythe` frame may be fixed to any suitable foundation, as 6b y designated at 4:. `'Ihejframe` comprises upper and lower bearings 5 and-6 -in which a shaft 7 Fixedonthe shaft betvveenfbearings 5 rotatablyinounted; the shaft being reduced in diameter near its lower end topro# vide aidoWnWardly facingshoulder 8 that `seats upon a thrust `bearing 9.
y and 6, bevel gear Wheel 1() that yis, adapted i tobe driven bya bevel gear 11 mounted on 'i the end of a drive shaft 12, The shaft 12 is supported horizontally in bearings13` and 14 and may be driven by `any vsuitable "means,`
such` as through thespur gea-r as,V4 indicated at15.` i
The upper end of shaft 7 is cupped to' form` a seat 16 for ahardened steel ball 17 which provides a universal bearingformounting the moldgcoaxialjwith the shaft by means of `cupped seat 18 in therbaseplate 19,7016 the mold; `vvhosesides are made up of aplu- `baseplate 19 and flanges 22, and serve" to rov et i tate the mold about its vertical axis; the up-v Vper end ofthe moldf beinglmaintained in a substantially true vertical" position 1 by means of a tubular top ournal 80, Tha-ving* a flange 31 securedby bolts`32 totop flanges 23', and rotatively mounted in bearing 33 supported byk suitable cross members 34 that, in turn, arereinovably fastenedto a towerlke-struc ture (not shown) which is adapted to facilitate the Work of the operator.
Tubular journal 30 is made of sullicient length to project through a loose fitting cy lindrical aperture provided in the bottom of a discharge basin 36 removably supported by cross members 34. A horizontally disposed, internallythreaded,annular disc 3? is screwed onto the 'threaded top of journal 30, Vafter discharge basin 36 is placed in position, the several parts functioning as hereinafter described. A trough 33 having a funnel-like end 39 and suitably supported, as at '40, is used to facilitate pouring the fluid concrete into the mold. i y
This construction permits the use of molds of various lengths and 'greatly facilitates the carrying out of the process. The ball universal bearing, supporting ythe mold, and the torque pins greatly reduce the time required to mount the mold over former methods, and assure the smooth operation of the apparatus even when there is considerable variation inthe coaxial alinement of the axis of shaft 7 and axis of the mold. 1 l
The mold sections may be constructed to form poles of a wide variety of designs hav,- ing circular, hexagonal, fluted or other cross sectional shapes. The 'mold here shown, for simplicity, has been made of circular cross section. j If the 'poles are to contain vertical reinforcing bars 4l and spirals 42, as illustrated in Figures 2 and 3, these are assembled preferably as a unit by means of tie Wires 43, two or more sets of cross rods 44, Welded at their junction points 45, being used to position the reinforcement centrally in the mold. A conduit pipe 46 to carry electric circuit Wires may also be located centrally of the mold by means of cross rods 44 as shown. The 'reinforcement unit vand conduit are preferably placed Within the mold prior to securing` the mold sections together. Plugs or corks'47 are used to close the ends of the conduit until after the concrete is set.
The rotation of the'mold is preferably opposite to the direction traced in following down the spiralling'of'the reinforcement, as indicated by the arrow across the near side of shaft 7 for the spiral reinforcing illustrated in Figure l. ThisV has been found to facilitate the process in the elimination of voids, b y Working the concrete doivnu'ard as it enters the mold.
,ln carrying'out the process, the mold and apparatus are assembled as illustrated in Figure l and the mold rotated at a suitable speed by means of an electric motor or other motive power (not shown), While yfluid concrete, or other material, is poured slowly into the mold.
Means (not shown) are provided Whereby the operator may adjust the speed of rotation of the mold to such value that the solids build up Within the mold in the form of a basin resembling a vertical paraboloid into which the air bubbles and excess Water, or suds, are squeezed as the solids are centrifuged against the Walls and settle at the center of the mold. Much care is taken during the pouring process to prevent the trapping of air or .excess Water by too rapidly pouring in the material; and the para bolo'idal basin is maintained by proper speed control for the various diameters. As the concrete rises Within the mold, the suds are spilled from the tubular top journal 30 over annular disc 37, from which it is centrifuged into `discharge basin 36 and from there flows away from the apparatus through spout 48 'and trough 49. In this Way, top journal 30 and bearing 33 are effectively protected from the suds Which are conducted to a desirable point of discharge. After the mold is thoroughly filled the rotation is stopped, trough 38 `is removed and disc 37 is unscrewed, thus permitting the removal of bearing 33 and its supports 34 preparatory to removing the mold from the rotation apparatus by a crane or other suitable means. Tubular journal v30 is then taken off by removing bolts 32 and the concrete smoothed off' level With flanges 23, thus `exposing the yend of conduit pipe 46. After th'e material has sufficiently set, bolts 24 and 25 are removed and the mold sections stripped from `the finished article. v
The "ce'i'itrifuging of fluid concrete fivith the mold is "so effective 'in precipitating the solids that the suds spilled 'from the 'top do not contain even a practicable amount of cement.
It has been found by following out the vsteps of the abovedescribedfprocess A:that poles and posts may be. "madethat are abso- 'lutely free from surface 'or interior voids, and checks; and that the exterior follows faithfully the contour of thei'mold, 'thus mailt# ing it vcommercially practicable to manufacture concrete street lighting standards of any desired design.
j.Trlaving thus described my invention,v what I claim as new 'therein Yanddesire to secure by 'Letters-Patent, is:
, l. The process of manufacturing poles, o'r the like, which consists in mounting a mold vertically forpaxial rotation, slowly pouring a concretious material into the upper end of the mold While it is rotating at such speed so as to cause the material to build up Within the mold in the form of a basin.
2. The process of manufacturing poles,`or the like, which consists in mounting a mold vertically for laxial rotatio'n, slowly 'pouring a eoncretious material into the Iupper end of the Vmold While'it is rotating at `such speed as to cause the material to build up Within the mold in the form 'of Va paraboloidal basin in which theexcess Water squeezed from the material will be carried upwardly andiinally spilled from the top of the mold, then stripping the mold from thepoleafter the material hasset. v
3. The process of manufacturing poles containing a longitudinally disposed conduit pipe, which consists of mounting a mold vertically for axial rotatiomplacing a conduit pipe axially within ,the mold and pouring a concretious material into the upper end of the mold while it is rotatedy at such speed as to cause thc material to build up within the mold in the form of a paraboloidal basin and then removing the mold from the pole after `the material has set.
.4. The process of ,manufacturing rein-l forced poles containing a longitudinally dis- -posed conduit pipe which consists of mounting a mold vertically for axial rotation, placinga conduit pipe axially within the mold, placing reinforcing members within the mold, filling the mold with a concretious material poured slowly into its upper end as the mold is rotated at such speed as to causethe material to build up about the pipe in the form of a paraboloidal basin, Vthen `stripping the mold from thepole` after the material has set.
5. The method of manufacturing poles ofA `the character described containing spiral re-` inforcement which consists of placing the spiral reinforcement in a mold, mounting the mold vertically for axial rotation, slowly pouring a concretious material in the mold into the upper end as said mold is rotated opposite to the directiontraced by following down the spiralling of the reinforcement.
6. A device of the character described comprisingan upright mold adapted to be filled through its upper end, a universal bearing` concentrically on the upper end of said shaft through the intermediacy of a universal bearing, an, alinement bearing `for the upper end l ofthe mold andmeans fixed to and extending` 1 laterally fromthe shaft and operatively connec/ted to rotate the mold with the shaft.
8. A device of the character described comprising a vertical, revolubly driven shaft, an
upright mold adapted to beiilled through its Y, upper end having its base mounted centrally on theupper end of said shaft through the in-V termediaey of .aninterposed universal bearing, an alinement bearing'rotatably containing the upperend of the mold, aV torque arm fixed to the shaft and pins on the arm engagng the base of the mold to cause to be rotated with the shaft.`
9. fA device: of the, character described loom- ;prisingia verticalrevolubly drivenf` shaft, an i upright mold having `its fbasefcentra'lly sup;- ported on the upper end of said ,shaft through the intermediacy oflaf universal bearing, a
4toro ue arm` fixed. to 1 the shaftpins extended upwardly from the `arm` and engaging ,the
base of the mold tocause itto rotatewith thefshaft, annpper frame structurehaving cylindrical opening forming an alinei'nent bearing, a tubularjournal extending coaxial`` "from theupperend of the mold and rotatably contained inr said p bearing and adapted to receive the material therethrough forflliii-gthemold. p i ma 10..l A device Aof the l character i described l comprising `a vertical, *revolubly drivenshaft,
an upright mold having `its/base. centrally i sui'ap'orted[onA the upperf end of said shaft through the intermediacy of auniversal bearing, a torque arm fixed tothe shaft, `pins extended upwardly from the arm and engaging the base of the mold to cause it to rotate with the shaft. an upper frame structure, a
discharge basin mounted by said upper frame` structure and having a cylindrical aperture forming an alinement bearing, a tubular vjournal mounted on the upper end of the `mold" and extending rotatably throughsaid alinement bearing and adapted toreceive the material therethrough for filling the mold.
11.'A device of the character described comprising a vertical, revolubly driven shaft,
an upright `mold having its base centrally` supported on the upper end of said sha-ftv through the intermediacy of a` universal bearing, a torque arm fixed to the shaft,pins
ico
exten ded upwardly from thearm and engaging the base of the mold to cause it to rotate with the shaft, an upper frame structure,
a discharge basin mountedby said .upper :los
frame structure and having a cylindrical y' aperture forming an alineinent bearing, a
tubular journal-mountedon the upper end of the mold and extending rotatably through said alinement bearing and adapted to receivejthe material therethrough for fillingthe mold and an annular disk mounted on the upper end of said journal. i
12. A device of the character described comprising a vertical.l revolubly driven shaft,
anupright mold having itsbase centrally supported on the upper yend of said shaft through'the intermediacy of a universal bearing, a torquearm fixed to the shaft, pinsextended upwardly `from thearm and engagwith the shaft, an upper frame structure, a discharge basin mounted by said upper frame structure and having a cylindrical aperture forming an alinement bearing, a tubular journal mounted on the `upperend of the mold and extending rotatably through said alinement bearing and adapted to receive the l material therethroughfor filling `the mold,
.ing the base of the mold to cause'it to rotate Y an annular disk mounted on the upper end `of said journal and means for feeding a concretious material into the mold through the tubular journal.
13. The process of forming poles of the character described, which consists of mounting a mold vertically for axial rotation, preiparing a mixture of concrete rhaving a high Water-cement ratio to render the mixture excessively Huid, pouring the mixture into the -mold While the latter is rotated at such speed `as 'to cause the material to buildup within 4the 'mold in the form of a paraboloidal basin Ain which the excessive Water squeezed from the material will be carried upwardly and finally spilled 'from the top of the mold.
Signed at Seattle, lVashington, this 27th 'day'of August, 1926.
J'STUS F. NE PAGE.
US145568A 1926-11-01 1926-11-01 Centrifugal molding device Expired - Lifetime US1777763A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003080941A1 (en) * 2002-03-25 2003-10-02 Dov Steinberg Molded concrete foundation element and method for its manufacture

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003080941A1 (en) * 2002-03-25 2003-10-02 Dov Steinberg Molded concrete foundation element and method for its manufacture
US20050118297A1 (en) * 2002-03-25 2005-06-02 Dov Steinberg Molded concrete foundation element and method for its manufacture

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