US3279740A

US3279740A - Expandable core-former

Info

Publication number: US3279740A
Application number: US472786A
Authority: US
Inventors: Leonard D Long
Original assignee: LONG CONSTRUCTION CO
Current assignee: LONG CONSTRUCTION CO
Priority date: 1965-07-19
Filing date: 1965-07-19
Publication date: 1966-10-18
Anticipated expiration: 1983-10-18

Description

Oct. 18, 1966 l.. D. LONG 3,279,740

EXPANDABLE CORE-FORMER Original Filed Aug. 25, 1960 2 Sheets-Sheet l FIG. @94 70@ '70a 7 @9e 7/9 70e BY' 694 Mg M Mu? 770 FIG. 5 'L HTroRNEs/s.

'ct 18, 1966 L. D. LONG 3,279,740

l' EXPANDABLE CORE-FORMER original Filed Aug. 25, 1960 I 2 sheets-sheet 2 FIG.` s

688 686 INVENTOR.

United States Patent 3,279,740 EXPANDABLE CORE-FORMER Leonard D. Long, Long Construction Co., P.0. Box 288, 2110 Mount Pleasant St., Charleston, S.C.

Application Aug. 1, 1962, Ser. No. 215,218, now Patent No. 3,210,039, dated Oct. 5, 1965, which is a division of application Ser. No. 51,972, Aug. 25, 1960, now

Patent No. 3,090,093, dated May 21, 1963. Divided and this application July 19, 1965, Ser. No. 472,786

4 Claims. (Cl. 249-181) This invention relates to a core-former, and more particularly to an expandable core-former for producing cores in cored building blocks and the like. This application is a division of my copending application Serial No. 215,218, tiled August 1, 1962, now Patent No. 3,210,039, yissued October 5, 1965, which is a division of my application Serial No. 51,972, filed August 25, 1960, now Patent No. 3,090,093, issued May 21, 1963.

It is an object of my invention to provide a coreformer which can be expanded by a rotational thrust force, which can be uniformly expanded throughout its length, which can be expanded against the action of substantial counter-forces, which can be maintained in a xed position and orientation during its expansion, and which wi-ll prove sturdy and durable in use.

In accordance with one form of my invention, the core-former comprises a plurality of core segments having inwardly presented thrust-receiving faces which are operatively engaged by thrust-transmitting cam means mounted on a first shaft interposed between the core segments and rotatable to `cause said cam means to move the core segments into spaced relation to each other for expanding the core-former. Conveniently, the core segments are operatively interconnected whereby upon reverse rotation of said first shaft said core segments will be moved toward each other to collapse the core-former. A second shaft is disposed around the first shaft and is operatively interconnected to the core segments for moving the core-former to and from an operative position in a mold.

A plurality of face plates are operatively connected to the severa-l core segments to bridge the spaces between said segments and prevent the entry of the material being cored from entering into the interior .of the core-former from the sides thereof when said core-former is expanded. Plate means are interposed between the opposed ends of the core segments and cover plates on the ends of the face plates to prevent the material being cored from entering into the interior of the core-former from the ends thereof.

Other objects and features of my invention will become apparent from the more detailed description which follows and from the accompanying drawings, in which:

FIG. 1 .is a vertical section through an expandable core-former embodying my invention;

FIG. 2 is a horizontal section taken on the line 2-2 of FIG. 1;

FIG. 3 is a horizontal section taken on .the line 3 3 of FIG. 6;

FIG. 4 is a fragmentary enlarged vertical section of the core-former shown in FIG. 1, but taken on an oblique core-former axis and showing the core-former in expanded position;

FIG. 5 is a horizontal section taken on `the line 5 5 of FIG. 1, but showing portions of the core-former broken away;

FIG. 6 is a vertical section similar to FIG. 1, but showing the core-former in expanded position;

3,279,740 Patented Oct. 18, 1966 ICC FIG. 7 is an enlarged isometric view of the spider block shown in FIG. l;

FIG. 8 is an enlarged isometric View of the pilot block shown in FIG. l;

FIG. 9 is a fragmentary enlarged vertical section similar to FIG. 4, but showing the opposite end Iof the coreformer; and

FIG. 10 is a bottom plan view of the core-former shown in FIG. l, but with portions thereof broken away.

My core-former is adapted to be used in combination with an apparatus of the type disclosed in my U.S. Patent No. 3,090,093, issued May 2l, 1963, for producing molded components having cores formed therein. The construction of my core-former is such that it can be inserted in a collapsed condition into an appropriate mold prior to the addition of the material to be molded, and then expanded to compress said material against .the inwardly presented mold walls. This permits the formation of high-density molded articles having cores formed therein.

For ease of description, the core-former is described herein as being used to produce cored building blocks formed from an aggregate mixture. It is to be understood, however, that my core-former can be used for producing various other types of cored elements.

The core-former is movable into and out of operative position in a mold by means of a shaft 675 projecting outwardly from its connect-ion -to the core-former. As shown in FIG. 1, the lower end of the shaft 675 is threadably connected to a spider block 678 having a plurality of outwardly projecting arms 680 disposed on the oblique core-former axes. The core-former is expanded by means of a rotatable shaft 682 extending upwardly through the shaft 675 for connection to a rotational power source. A quadri-loaded cam 684 whose cam lobes are disposed on the transverse core-former axes when said core-former i-s in its collapsed position is mounted on the lower end of the shaft 682. As shown in FIG. 1, the upper face of the cam 684 is rotatably slidable against the lower face of the spider block 678, and the lower face of said cam is rotatably slidable on the upper face of a second spider block 686 rotatably connected to the lower end of the shaft 682, as by a bolt 688. The spider block 686 also has a plurality of outwardly projecting arms 690 parallel to the spider arms 680, and is further provided with a pilot 692 projecting outwardly from the lower end of the core-former for reception in an opening in the bottom of a mold to engage the faces thereof and prevent the core-former from rotating in the mold.

As shown in FIG. 2, the core-former is provided with four elongated core segments 694, eac-h of which has a pair -of outer faces normal to each other and an inner face provided with an inwardly projecting cam follower 696 which is receivable between a pair of lobes on the cam 684 when the core-former is in its collapsed position. Adjacent each of its ends, each of the cam followers 696 is provided with openings 698 adapted to slidably receive the

spider arms

680 and 690 whereby said arms will guide the movements of the core segments during expansion and collapse of the core-former. A second set of openings 699 is also formed in each of the cam followers 696 adjacent each of its ends for the reception of coil springs 700 secured to the core segments as by pins 702. The

inwardly presented ends of the springs 700 are received in

openings

703 and 703 formed in

spider blocks

678 and 686, respectively, and are retained therein by pins 704. As will be clear from FIGS. 3 and 4, the springs 700 and the

spider arms

680 and 690 are all disposed on the )oblique axes of the core-former.

In order to prevent aggregate from entering the coreformer when it is in expanded position, I mount a plurality of face plates '706 on the several core segments 694. As shown in FlG. 2, each of the face plates 766 has a width corresponding to the width of the coreformer in collapsed position so that it bridges the space between a pair of adjacent core segments when the coreformer is in expanded position. Each of the face plates 766 has a rib 768 extending inwardly `therefrom between a pair of adjacent core segments 694 for connection to a slide 710 slidably carried in aligned slots formed in the adjacent faces of a pair of adjacent core segments. Extending inwardly from the upper and lower ends of the face plates 766 are top and bottom cover plates'712 and 7M, respectively. The top cover plates 712 extend inwardly over a screed plate 716 interposed between said cover plates and the upwardly presented faces of the spider block 57S and the core segments 694. Similarly, the bottom cover plates 714 extend inwardly over a pilot plate 7i8 interposed between said cover plates and the downwardly presented faces of the spider blo-ck 686 and the core segments 694. Conveniently, the screed and

pilot plates

716 and 718 have lateral extents only slightly smaller than the lateral extent of the core-former in its collapsed position so that they will act in combination with the

cover plates

712 and 714 t-o prevent aggregate from entering the ends of the core-former when it is in expanded position. As shown, the edges of the face plates 706 and their

cover plates

712 and 714 are beveled, as at 719, so that upon collapse of the coreformer said face and cover plates will screed any aggregate from the outwardly presented faces of the core segments and the screed and pilot plates.

Thus, `the operation of the core-former shown in FIGS. 1-10 may be described as follows: The shaft 675 is moved axially to position the core-former in a mold with the pilot 692 seated in an opening formed therein, and the shaft 682 is rotated through a 45 angle in a clockwise direction as viewed in FIG. 2 to cause the lobes on the cam 684 to bear against the cam followers 697 to thus move the core segments outwardly in spaced relation to each other on the oblique core-former axes. As the core segments are moved to their expanded positions, they are guided by the

spider arms

680 and 690 sliding in their respective openings formed in the cam followers 696, and by the face plate slides 710. With the core segments in this expanded position shown in FIG. 3, the face plates 706 bridge the spaces between the spaced pairs of adjacent core segments along the side faces of the core-former to prevent the entry of aggregate therein. And the top and

bottom cover plates

712 and 714 cooperating with the spider plate 716 and pilot plate 71S prevent the entry of aggregate from the core-former from the top and bottom thereof.

To retract the core-former to its collapsed position, the shaft 682 is rotated in a countercl-ockwise direction as viewed in FIG. 3. Such rotation moves the lobes on the cam 684 out of bearing engagement with the cam followers 697, and the core segments 694 are thus pulled inwardly on the oblique core-former axes by the springs 70). The inward collapsing movement of the core segments 694 is also guided by the

spider arms

680 and 690 and by the slides 710 on the face plates 706. During this inward movement of the core segments, the beveled edges of the face plates 7 06 and the top and

bottom cover plates

712 and 714 will slide along, and screed any aggregate from, the outer faces of the core segments 794 and the screed and

pilot plates

716 and 718.

I claim:

1. An expandable core-former, comprising a plurality of core segments movable with respect to each other and having cam followers projecting inwardly on the oblique core-former axes, a first shaft movable for m-oving the core-former to and from an operative position in a mold,

a first spider block mounted on said first shaft and having a plurality of outwardly projecting arms slidably received in openings formed in the core segments adjacent one of their ends, a second shaft rotatably carried in said first shaft and first spider block and interposed between said core segments, cam means on said second shaft rotatable therewith in one direction to engage said cam followers and force said core segments uniformly outwardly from each other to expand the core-former, a second spider block rotatably mounted on said second shaft at the end of said cam means remote from said first spider block and having a plurality of outwardly projecting arms parallel with the arms on said first spider block and slidably received in openings formed in the core segments adjacent their ends remote from Said first spider block, spring means interconnecting each of said core segments to said spider blocks to move Ysaid core segments inwardly upon rotation of the cam means in an opposite direction, said spider block arms and spring means lying in the planes of the oblique core-former axes, and means on said spider blocks and core segments bridging and closing the spaces between tops, bottoms, and sides of said core segments.

2. An expandable core-former as set forth in claim 1 in which said cam means are rotatable against the lower and upper faces of said first and second spider blocks, respectively, each of said cam followers extends beyond the ends of said cam means and the openings in said core segments are formed in said cam followers, to slidably receive the arms of said first and second spider blocks, and said spider blocks and cam followers have aligned openings for reception of said spring means.

3. An expandable core-former, comprising a plurality of core segments movable with respect to each other and having cam followers projecting inwardly on the oblique core-former axes, a first shaft movable for moving the core-former to and from an operative position in a mold, a first spider block mounted on said first shaft and having a plurality of outwardly projecting arms slidably received in openings formed in the cam followers adjacent one of their ends, a second shaft rotatably carried in said first shaft and first spider block and interposed between said core segments, cam means on said second shaft rotatable therewith in one direction to engage said cam followers to for-ce said core segments uniformly outwardly from each other to expand the core-former, a second spider block rotatably mounted on said second shaft and having a plurality of outwardly projecting arms parallel with the arms on said first spider block and slidably received in openings formed in the cam followers adjacent their ends remote from said first spider block, means interconnecting said core segments to said spider blocks to move said core segments inwardly upon rotation of the cam means in an opposite direction, said spider block arms and said means interconnecting the core segments to the spider blocks lying in the planes of the oblique core-former axes, a pair of screed plates disposed over the opposed ends of said first and second spider blocks and slidably received on the opposed ends of said core segments, a plurality of face plates mounted on said core segments having cover plates received over said pair of screed plates whereby said pair of screed plates and said face and cover plates close and bridge the spaces between the tops, bottoms, and sides of said core segments, and ribs on said face plates interposed between adjacent pairs of core segments and provided with slides slidably received in aligned slots formed in said adjacent pairs of core segments.

4. An expandable core-former as set forth in claim 3 in which said second spider block has a pilot projecting `through one of said pair of screed plates for releasably retaining the core-former in a non-rotatable position in a mold.

(References on following page) 5 6 References Cited by the Examiner 2,315,634 4/ 1943 McCall 249-179 2 878 545 3/1959 Lowe 25-128 UNITED STATES PATENTS 6/1889 Bennett 24g-181 3,064,439 11/1962 Cobl 25-128 X 10/1904 shell 249-147 5 FOREIGN PATENTS 6/ 1905 Pettyjohn 249-147 X 8,333 2/ 1908 France. 3/ 1906 Landmann. 6/1912 Whitman. J. SPENCER OVERHOLSER, Primary Examiner. 10/ 1942 George 25-41 J. H. FLINT, Examiner.

Claims

1. AN EXPANDABLE CORE-FORMER, COMPRISING A PLURALITY OF CORE SEGMENTS MOVABLE WITH RESPECT TO EACH OTHER AND HAVING CAM FOLLOWERS PROJECTING INWARDLY ON THE OBLIQUE CORE-FORMER AXES, A FIRST SHAFT MOVABLE FOR MOVING THE CORE-FORMER TO AND FROM AN OPERATIVE POSITION IN A MOLD, A FIRST SPIDER BLOCK MOUNTED ON SAID FIRST SHAFT AND HAVING A PLURALITY OF OUTWARDLY PROJECTING ARMS SLIDABLY RECEIVED IN OPENINGS FORMED IN THE CORE SEGMENTS ADJACENT ONE OF THEIR ENDS, A SECOND SHAFT ROTATABLY CARRIED IN SAID FIRST SHAFT AND FIRST SPIDER BLCOK AND INTERPOSED BETWEEN SAID CORE SEGMENTS, CAM MEANS ON SAID SECOND SHAFT ROTATABLE THEREWITH IN ONE DIRECTION TO ENGAGE SAID CAM FOLLOWERS AND FORCE SAID CORE SEGMENTS UNIFORMLY OUTWARDLY FROM EACH OTHER TO EXPAND THE CORE-FORMER, A SECOND SPIDER BLOCK ROTATABLY MOUNTED ON SAID SECOND SHAFT AT THE END OF SAID CAM MEANS REMOTE FROM SAID FIRST SPIDER BLOCK AND HAVING A PLURALITY OF OUTWARDLY PROJECTING ARMS PARALLEL WITH THE ARMS ON SAID FIRST SPIDER BLOCK AND SLIDABLY RECEIVED IN OPENINGS FORMED IN THE CORE SEGMENTS ADJACENT THEIR ENDS REMOTE FROM SAID FIRST SPIDER BLOCK, SPRING MEANS INTERCONNECTING EACH OF SAID CORE SEGMENTS TO SAID SPIDER BLOCKS TO MOVE SAID CORE SEGMENTS INWARDLY UPON ROTATION OF THE CAM MEANS IN AN OPPOSITE DIRECTION, SAID SPIDER BLOCK ARMS AND SPRING MEANS LYING IN THE PLANES OF THE OBLIQUE CORE-FORMER AXES, AND MEANS ON SAID SPIDER BLOCKS AND CORE SEGMENTS BRIDGING AND CLOSING THE SPACES BETWEEN TOPS, BOTTOMS, AND SIDES OF SAID CORE SEGMENTS.