US3806297A

US3806297A - Concrete precasting machine

Info

Publication number: US3806297A
Application number: US00186725A
Authority: US
Inventors: M Scales
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-10-05
Filing date: 1971-10-05
Publication date: 1974-04-23
Anticipated expiration: 1991-04-23

Abstract

A concrete precasting machine in which inner and outer molds forms are supported on a vibration table. The concrete is fed to the molds through a conical shut off valve which retains excess concrete on the conveyor belt when conveyor is retracted and thus prevents overfilling of the mold and spillage of concrete on the floor. The outer mold form and cast article are supported on a pallet and are together separable from an inner mold. The machine permits practically continuous casting with a minimum of slack time between pouring operations.

Description

United States Patent 1191 Scales I CONCRETE PRECASTING MACHINE [76] Inventor: Michael J. Scales, PO. Box 1111,

' Newburgh, NY. 12550 22 Filed: Oct. 5, 1971 211 Appl.No.: 186,725

[58] Field of Search 425/253, 256, 258, 262,-

[56] I References Cited UNITED STATES PATENTS 1,982,757 12/1934 Hick 249/66 A 2,616,146 11/1952 Haase 249/152 3,542,914 11/1970 LaVergne 249/144 X 2,321,277 6/1943 Boyle 425/421 X 3,416,204 12/1968 Waddington... 425/432 X 1,458,145 6/1923 Parsons 249/152 3,141,222 7/1964 Steiro....; 425/262 2,615,228 10/1952 Regan..... 425/253 X 2,966,714

1/1961 Enays 4251432 3,078,539 Duplessis 425/432 X 3,201,843 8/1965 Osweiler 425/421 X 3,461,516 8/1969 Botlcher 425/438 X 3,614,054 10/1971 Beasley 249/144 X 3,205,552 9/1965 Johnson et a1... 249/161 3,032,851 5/1962 Gibbs 425/447 X Primary Examiner-Robert D. Baldwin Assistant Examiner-John McQuade Attorney, Agent, or FirmBerman, Bishoff & Platt 57 ABSTRACT A concrete precasting machine in which inner and outer molds forms are supported on a vibration'table.

The concrete is fed to the molds through a conical shut off valve which retains excess concrete on the 1 conveyor belt when conveyor is retracted and thus prevents overfilling of the mold and spillage of concrete on the floor. The outer mold form and east article are supported on a pallet and are together separable from an inner. mold. The machine permits practi cally continuous casting with a minimum of slack time between pouring operations.

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I I y I 1 CONCRETE PRECASTING MACHINE BACKGROUND OF THE INVENTION SUMMARY on THE INVENTIO In the present invention inner and outer mold forms are supportedon a vibration table and concrete is fed between the forms with a conical valve cutoff arranged to prevent spillage and overfilling of the molds.

The primary object of the invention isto provide a versatile concrete .pr'ecasting machine which permits nearly continuous operation in the production of regular and odd shaped prefabricated concrete articles such as manholes, conduits and the like.

, Another object of the invention is to provide a device as the type described above in whichthe article is re- I moved from the molds prior to curing and supported on a pallet during curing.

A further object of the invention is to provide a highly versatile concrete precasting machinewhich can accomodate molds of vastly differing shapes and sizes BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of the invention;

FIG. 2 is a front elevation of the invention;

FIG. 3 is a horizontal sectional view taken on the line 3-3 of FIG. 2 looking in the direction of thearrows;

FIG. 3a is an enlarged vertical sectional view taken on the line 3a-3aof FIG. 3 looking in the direction of the arrows;

FIG. 12 is a horizontal sectional view taken on the line 12-12 of FIG. 11 looking in the direction of the arrows; I

FIG. 13 is a fragmentary front elevation of a mold lock;

FIG. 14 is a horizontal sectional view taken on the line 14-14 of FIG. 13 looking in the direction of the arrows;

FIG. 15 is a fragmentary top plan view of the mold guide;

FIG. 16 is a vertical sectional view taken on the line 16-16 of FIG. 15 looking in the direction of the arrows;

FIG. 17 is a vertical sectional view taken on the line 17-17 of FIG. 16 looking in the: direction of themrows;

FIG. 18 is afragmentary top plan view of a mold on the vibrating table;

FIG. 19 is a vertical sectional view taken on the line 19-19 of FIG. 18 looking in the direction of thearrows; e

FIG. 20 is an enlarged fragmentary vertical sectional view taken on the line 20-20 of FIG. 19 looking in the direction of the arrows;

FIG. 21 is a transverse sectional view taken on the line 21-21 of FIG. 20'lookinginthe direction of the arrows; I

FIG. 4 is a top plan view of the casting mold as seen I from the line 4-4 of FIG. 1 looking in the direction of the arrows; FIG. 5 is a front elevation of the casting mold of FIG.

FIG. 6 is a fragmentaryvertical sectional view taken on the line 6-6 of FIG. 4 looking in the direction of I the arrows;

FIG. 7 is an enlarged fragmentary vertical sectional view taken on the line 7-7 of FIG. 6 looking in the direction of the arrows; I

FIG. 8 is an enlarged fragmentary horizontal sectional view taken on the line8-8 of FIG. llooking in the direction of the arrows; I

FIG. 9 is afragmentary vertical sectional viewtaken on the line 9-9 of FIGS looking in the direction of the arrows;

FIG. 10 is a top plan view of one of the cranes forming part of the invention;

FIG. 11 is a front elevation of the crane of FIG. 10 shown partially broken away and in section for convenience of illustration;

' FIG. '22 is a bottom plan view of the structure illustrated in FIG. 20;

FIG. 23 is a horizontal sectional view taken on the line 23-23 of FIG.19 looking in the direction of the arrows;

line 25-25 of FIG. 24 looking in thedirection of the arrows;

FIG. 26 is' a perspectiveview of the handling crane;

"FIG. 27 is' a top plan view of one of the molds used withtheinvention; I

FIG.28 is afragmentary verticalwsectional view taken along-the line- 28-28 of FIG. 27 looking in the direction of the arrows; I

FIG. 29 is a vertical sectional view of a manhole mold shown in position on the vibrating table;

I arrows;

FIG. 31 is a bottom plan view of the manhole mold as seen from the line'31-31 of FIG. 29 looking in the direction of the arrows;

- tional view taken on the line 34-34 of FIG. 33 looking FIG. 36 is a fragmentary sectional view taken on the line 36-36 of FIG. looking in the direction of the arrows;

FIG. 37 is a perspective view of a rung adapted to be inserted into the wall of a manhole cast by the apparatus of the present invention;

FIG. 38 is a fragmentary horizontal sectional view of a portion of the manhole produced in the apparatus of FIG. 33 showing a rung in solidlines prior to insertion in the wall of the manhole, the dotted lines showing the rung in place in cavities in the manhole wall;

FIG. 39 is a side elevation view of the mechanism illustrated in FIG. 35 and 36 with parts broken away for convenience of illustration; and

FIG. 40 is a perspective view of a manhole produced by the apparatus of the present invention, shown partially broken away and in section for convenience of illustration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS I Referring now to the drawings in detail whereinlike reference characters indicate like parts throughout the several figures the reference numeral indicates generally the apparatus of the present invention.

The apparatus 50 includes a vibrating mold support indicated generally at 51 consisting of a vibration table 52 mounted on springs 53 extending upwardly from a base 54. The vibration table 52 and base. 54 are disposed in a floor recess 55 with the upper surface of the vibrationtable 52 generally aligned with the surface of the floor.

The apparatus 50 includes a tower 56 of generally rectangular form and having an upright angle iron member 57 in each inside corner thereof. A vertical rail 58 is secured to each of the angle iron members 57 by bolts 59. The angle iron frame member 57 is secured to the'tower 56 by bolts 60 which extend through transverse slots 61 in the tower 56. The angle iron member 57 is a horizontally adjustable on the tower 56 and an adjustment screw 62 engages against the angle iron member 57 to support it in adjusted position.

' Aconcrete conveyor generally indicated at 63, includes a pair ofchannel tracks 64 which extend upwardly and inwardlyfrom a base frame 65 to a power frame 66 mounted-on top of the tower 56.

A traveling bin 67 is mounted on rollers 68 which engage in the channel tracks 64. A cable 69 is secured to the bin 67 and is wound on a winch 70 mounted on the power frame 66. An electric motor 71 drives the winch 70 through a power transmission 72. The electric motor 71 and power transmission 72 are both mounted on the power frame 66.

A conveyor 73 conveys concrete from the mixer 74 to the bin 67 when the bin 67 is in its lowermost position. As the bin 67 is raised on the channel tracks 64 by the winch 70 the upper roller 68 thereof moves outwardly in a horizontal track 75 and, the lower roller 68 continues on up in the channel track 64. This movement of the rollers 68 causes the bin 67 to upend, as shown in dotted lines in FIG. 2, dumping its contents into the top of the tower 56.

A generally rectangular carriage 76 is mounted for vertical reciprocation in the tower 56 and has a plurality of flanged wheels 77 journalled on stub shafts 78 fixed to the carriage 76. The flanged wheels 77 engage the track 58 to guide the carriage 76 for vertical movement within the tower 56. A plural section hydraulic ram 79 is mounted centrally of the tower 56 and is secured to the lower end of the carriage 76 for moving the carriage 76 vertically in the tower 56.

A hopper 80 is secured in the top of the carriage 76 in a position to receive concrete dumped therein from the traveling bin 67.

A generally horizontal frame 81 is mounted for horizontal reciprocation on rollers 82 within the carriage 76. A hydraulic cylinder 83 is mounted in the carriage 76 and has a piston rod 84 connected to the frame 81 to reciprocate the frame 81 horizontally in the carriage 76. An endlessbelt conveyor 85 is mounted on the frame 81 on a plurality of rollers 86 with the belt 85 extending for the full length of the frame 81. The belt 85 is trained over a large motor driven drive roller 87 at one end and over an idler roller 88 at its opposite end. The hopper 80 receiving concrete from the bin 67 directs all of it onto the conveyor belt 85 for movement thereon.

A concrete delivery unit indicated generally at 89 is mounted on the outer end of the horizontal frame 81 and travels therewith as the horizontal frame 81 is horizontally reciprocated by the hydraulic cylinder 83 and piston rod 84. The concrete delivery unit 89 includes an upright generally rectangular frame 90 secured -to the outer ends of the horizontal frame 81 and extending upwardly therefrom. A horizontal frame 91 is rigidly secured to the upright frame 90 and extends forwardly therefrom. Adjustable angular braces 92 extend from the upper portion of the upright frame 90 to the outer end portion of the horizontal frame 91 to assist in supporting and levelling the horizontal frame 91.

The frame 91 is generally circular and has a circular depending channel flange 93 secured thereto and carrying a plurality of flanged rollers 94 on the inner vertical face thereof. A deflector plate 95 is secured to the frame 91 and is spaced outwardly from the conveyor belt 85 to direct concrete delivered by the belt 85 downwardly through the horizontal frame 91.

A circular funnel member 96 is positioned within the channel flange 93 and has a circular angle track 97 secured to the outer face thereof and supported on the 1 flanged rollers 94 as can be plainly seen in FIG. 3a. The funnel member 96 has an upper cylindrical portion 98 and a lower inwardly converging portion 99 integrally secured thereto and depending therefrom.

The funnel member 96 is illustrated with its axis coaxial with the axis of the circular frame 91 but it should be understood that the funnel member 96 may be positioned off center to assist in the casting of eccentric cones, as well as, square and rectangular items.

A chute 100 is secured on aligned pivot pins 101 to opposite sides of the lower end of the funnel member 96. The chute 100 underlies the

funnel member

96 and 1 is adapted to receive concrete material therefrom.

A hydraulic cylinder 102 is mounted on the framev 91 centrally thereof in a perpendicular position. A piston rod 103 extends through the hydraulic cylinder 102 and projects substantially therebelow. A conical valve 104 is secured at its upper end to a fitting 105 detachably secured to the piston rod 103 and at its-lower end to a fitting 106 also detachably secured to the piston rod 103 at a point spaced well below the fitting 105. The conical valve 104 diverges downwardly and has its larger diameterslightly greater than the smallest diameter of the downwardly converging portion 99 of the funnel member 96. Theconical valve 104 is adapted to be raised and lowered by the hydraulic cylinder 102 so as to engage the funnel member 96 at its lower end to prevent the flow of concrete therefrom. The conical valve 104 is spaced from the funnel member 96 at its upper limit of travel to permit the flow of concrete from the funnel member 96.

A rotary hydraulic motor 107 is mounted in a bracket 108 carried by the frame 91 and has a belt 109 extending therefrom around the cylindrical portion 98 of the funnelmember 96 engaging between a pair of annular ribs 110. Rotation of the hydraulic motor 107 rotates the funnel member 96 along with the chute 100 to deliver concrete to the desired discharge point.

The horizontal frame 81 is aligned with the center of the vibration table 52 so that the concrete delivery unit 89 can be moved outwardly to overlie the center of any mold mounted on the vibration table 52.

The vibrating mold support 51 includes the horizontal flat vibration table 52 which carries a plurality of rotary air or electric vibrators 111 secured to the underside thereof and each having its horizontal axis of rotation arranged perpendicular to the adjacent vibrator 1 l 1'.

A plurality of generally rectangular guide blocks 112 having a sloping end wall 113 are detachably secured to the vibration table 52 to guide a mold base 114 into center position on the vibration table 52. The blocks 112 each have a guide pin' 115 which are adapted to engage in guide bores 116 in the vibration table 52.

The guide block 112 is positioned over an elongate slot 1 17 in the vibration table 52 and a pair of V blocks 118 are arranged on opposite sides of the slot 117 beneath the table 52 in spaced parallel relation. A T bolt 119 extends through a vertical bore 120 in the guide block 112 and has a T-head 121 on its lower end which is adapted to be moved downwardly through the slot 117 and turned at right angles to engage in the V blocks 1 l8as can be seen in FIGS. 15, 16 and 17. A nut 122 is threaded onto the upper end of the T bolt 119 to lock the guide block 112 in its adjusted position on the vibration table 52. j

A T,bolt 123 extends vertically through the mold base 114 and through an elongate slot 124 in the vibration table 52. A plurality of depending lugs 125 are secured to the underside of the vibration table 52 in spaced apart relation on opposite sides of the slot 124 to receive a T head 126 on the T bolt 123. The T bolt 123 is moved downwardly through the elongate slot 124 and the T head 126 is turned perpendicularly to the slot 124 to engage the lugs 124. A 'nut 127 is threaded onto the T bolt 123 to lock the mold base 114 tothe vibrating table 52.

Referring now to FIGS. 3 and through 12 a pair of identical hoists 128 and 129 are positioned on opposite sides of the vibration table 52 for reasons to be assigned. v

The hoists 128 and 129 each include an upright hollow cylindrical post 130 extending upwardly from a base plate 131. A plurality of angular gusset plates 132 are secured to the base plate 131 and to the post 130 to strengthen the 'post 130.

An I-beam 133 extends horizontally above the post 130 and is pivotally secured to the post 130 by a pivot bolt 134 which extends vertically through the top 135, it

of the post 130 and through the center of the bottom flange 136 of the beam 133. The web 137. of the I-beam to support the skirt 139 from the post 130 to provide additional bracing support for the beam 133.

Atable 142 is rigidly secured to the post 130 and extends horizontally outwardly therefrom and has a pivot 143 secured to its outer end. A hydraulic cylinder 144 is pivotally mounted on the pivot 143 at one end and has a piston rod 145 secured to a boss 146 by means of a pivot. pin 147. The boss 146is rigidly connected to the lower end portion of the'skirt 139. Operation of the hydraulic cylinder 144 turns the skirt 139 and beam 133 with respect to the post 130 about the pivot bolt .134; A hydraulic lock pin assembly 148 is secured to A hydraulic cylinder 151 is secured by a pivot pin I 152 'to the outer end of the beam 133 and extends generally perpendicularly downwardly therefrom. A piston rod 153 reciprocates in the hydraulic cylinder 151. and has a mold pressure head 154 de'tachably secured to the lower end thereof.

The hoist 129 is moved by hand and does not include the pivoting structure using the hydraulic cylinder 144, as described above for hoist 128.

In FIG. 26 a fragmentary portion of the beam 133 forming part of the hoist 129 is illustrated. An electric chain winch 155 is secured to the outer end portion of the beam 133 and has a depending hoist block 156 carried by a chain 157. The hoist block 156 is provided with a hook 158 to which is secured a beam 159 having securing chains 160 depending from opposite ends thereof. 1 .8

Referring now to FIGS. 4 through 7, 13 and 14 one of the molds used withthe invention is illustrated generally at 161. The mold 161 is supported on the mold base 114 having a plurality of channel frame members 162 secured to the underside thereof. The mold base 114 has a relatively large central opening 163 formed 1 therein for reasons to be assigned.

A generally cylindrical inner mold form 164 is supported on the base 114 surrounding the opening 163. An upper channel frame member 165 is secured to the upper inner edge of the inner m'old form 164 and a lower channel frame member 166 is secured to the lower inner face of the inner mold form 164 to assist in retaining the shape of the inner mold form 164.

'A generally flat circular table 167 is supported on the upper end of the inner mold form 164 and has a pair of rigid legs 168 depending from a point closely adjacent the center thereof for reasons to be assigned. A plurality of socket members 169 are secured to the under side of the table 167 in depending relation adjacent the peripheral edges thereof. A leg 170 is detachably mounted in each of the sockets 169 and releasably secured therein by a transverse pin 171. A pair of air jets 172 extend through the table 167 on opposite sides thereof and are connected to an air pressure pipe 173 for reasons to be assigned.

An elongate slot 174 opens through the center of the table 167 and a pair of V blocks 175 are secured to the under side of the table 167 on opposite sides of the slot 174 and parallel thereto. A bolt 176 having a T head 177 is engaged through the slot 174 and turned to engage in the V block 175. A nut 178 on the threaded upper end of the bolt 176 secures a cylindrical core 179 to the table 167. A loop 180 is welded to the underside of the table 167 adjacent the center thereof for reasons to be assigned. 1

An outer mold form generally indicated at 181 includes a pair of

semi-cylindrical halves

182, 183. The

halves

182, 183 meet along a pair of vertical joints 184. Upper channel frame members 185 are secured to each of the

halves

182, 183 adjacent the upper end thereof and lower channel frame members 186 are secured thereto adjacent the lower edges thereof. Upright channel frame members 187 extend between the

channel frame members

185, 186 intermediatetheir opposite ends. A hook element 188 is secured to each of the

halves

182, 183 at opposite sides thereof for reasons to be assigned. A latch pin 189 is rigidly mounted on each of the upright channel framemembers 187 to be engaged by an over dead center tightening lever 190 mountedon the mold base 114 to lock the outer mold form 181 to the base 114. Latch pins 191 are secured -to eachof the

halves

182, 183 in vertically spaced relation adjacent the vertical joint 184. An over dead center tightening lever 192 is secured to the

opposite half

182, 183 to cooperate with a respected latch pin 191 to hold the

halves

182, 183 together. A plurality of loops 193 are secured to the mold form 181 adjacent the upper edge thereof to provide means for disassembling the

semi-cylindrical halves

182, 183 as will be described.

' A generally Z shaped spigot pallet 194 of generally cylindrical form is engaged between the inner mold form 164 and the outer mold form 181 at the bottom thereof supported on the mold base 114.

In using the mold 161 the mold base 114 is mounted on the vibration table 52 as illustrated in FIGS. through 17 following which the inner mold form 165 is positioned onthe mold base 114. The spigot pallet 194 is engaged about the inner mold form 164 and the table 167 with

legs

168 and 170 attached is inserted in the inner mold form 164 and supported on the upper face thereof. The air pressure pipe 173 is then connected to a source of air under pressure. The outer mold form 181 is assembled and inserted over the inner mold form 164 and locked down to the mold base 1 14 by the tightening lever 190 and latch pins 189.

The air or electric rotary vibrators 111 are then energized to vibrate the table 52 and the mold 161 thereon.

evenly thereabout. The concrete builds up in the mold 161 until the table 167 is covered with concrete to a thickness substantially equal to the thickness of the walls formed between the inner mold form 164 and the outer mold form 181.

The concrete has sufficient water to complete the chemical reaction involved in the hardening of the concrete but insufficient to produce a wet or fluid material. Upon the completion of the filling of the mold 161 the vibration has caused the mold 161 to fill completely and-to compact therein so that the concrete obtains initial set almost immediately. The outer mold form 181 along with the pallet 194 and table 167 with the molded article therein are then moved as a unit to a curing location leaving the inner mold form 164 on the mold base 114. The outer mold form is then stripped away so that the table 167 and pallet 194 support the center portion and lower edge portion of the concrete article during the curing thereof. The concrete article cast in the mold 161 is the bottom section of a manhole which is cast in inverted position.

While not illustrated in FIGS. 4 through 6 a pressure head such as that illustrated in FIGS. 27 and 28 is normally secured to the mold 161 by means of slotted brackets 195 mounted on the outer mold form 181 in circumferentially spaced relation. The function of the pressure head when used is to compact the concrete in the mold 161.

. The air jets 172 provide means for separating the table 167 from the cured concrete article to permit the table 167 to be removed therefrom. The loop permits the attachment of hydraulic rams to remove the table 167 in an emergency. I

In FIGS. 18 and 19 another mold is indicated generally at 196. The mold 196 includes a mold base 114 secured to a vibrating table 52 as described above. An inner mold form 197 of generally cylindrical form is supported by an upper channel frame member 198 which is secured to the upper inner face thereof and extends above the upper edge of the inner mold form 197. A lower channel frame member 199 is secured to the lower inner face of the inner mold form 197 at the lower edge thereof. A central channel frame member 200 is secured to the inner mold form 197 intermediate the upper channel frame member 198 and the lower channel frame member 199. The

channel frame members

198, 199 and 200 each extend generally horizontally and are parallel to each other; A plurality of transversely extending frame members 201 extend across the upper portion of the inner mold form 197 and are secured thereto. The frame members 201 are'arranged in perpendicularly extending spaced parallel pairs to form a central pocket 202. An air or electric rotary vibrator 203 is mounted in the pocket 202 with its axis of rotation extending vertically perpendicular to the axis of rotation of the rotary air or electric vibrators 111. The pressure head 154 covers an inner dome 204 supported on and welded to the upper edge of the inner mold form 197 in engagement with the outer face of the upper channel frame member 198. A generally cylindrical Z shaped bell pallet 205 is supported on the mold base 114-completely surrounding the lower end portion'of the inner mold form 197. An outer mold form indicated generally at 206 is constructed substantially the same as the outer mold form 181.

A latch 207 is secured to the outer mold form 206 and has an elongate latch pin 208 which is provided with a semi-cylindrical extension 209. A coil spring 210

Claims

1. In a concrete casting apparatus, a funnel member, means for delivering concrete to said funnel member, a chute, having its upper end secured to said funnel member for receiving concrete delivered from said funnel member, a vibrating mold support table positioned below said funnel member, a mold base supported on said table, a split outer mold form supported on said mold base, an inner mold form supported on said mold base inwardly of and spaced from said outer mold form, a pallet extending between and contacting said inner and outer mold forms at the lower ends thereof, said chute positioned to deliver concrete from said funnel member to the space between said inner and outer mold forms, a tower, and a carriage vertically movable in said tower, said means for delivering concrete to said funnel member including a generally horizontal belt conveyor, means in said carriage supporting said conveyor for generally horizontal movement of said conveyor, said funnel member being secured beneath the outer end of said conveyor, a second table detachably supported on the upper end of said inner mold form, said chute delivering concrete to the space overlying said last-named table, and means for moving said outer mold form, said pallet, the molded concrete article and simultaneously moving said second table all from said base support to a curing position leaving said inner mold on said vibration table.

2. An apparatus as claimed in claim 1 including legs secured to and depending from said second table and extending downwardly within said inner mold form for supporting said second table in the curing position.

3. A device as claimed in claim 1 including a pressure head positioned over the upper edge of said outer mold, means detachably secured to said pressure head for engaging the upper surface of the poured concrete, and means on said pressure head for drawing said pressure head toward said outer mold to apply pressure to the upper surface of the concrete.

4. A device as claimed in claim 3 including meanS detachably securing the concrete upper surface engaging means to said pressure head.

5. A device as claimed in claim 4 wherein said means for engaging the upper surface of the poured concrete comprises a molding pallet.