US2887755A

US2887755A - Mold box stripping mechanism

Info

Publication number: US2887755A
Application number: US451477A
Authority: US
Inventors: Thomas K Zevely
Original assignee: WASHINGTON BRICK CO
Current assignee: WASHINGTON BRICK CO
Priority date: 1954-08-23
Filing date: 1954-08-23
Publication date: 1959-05-26
Anticipated expiration: 1976-05-26

Description

y 26, 1959 T. K:-ZEVELY 2,887,755 MOLD Box STRIPPING MECHANISM Filed Aug. 25, 1954 4Sheets-Sheet a INVENTQR Thorncs K. Zelq.

d mmo-n e dow-n,

ATTORNEYS May 26, 1959 ZAEVELYI MOLD BOX STRIPPING MECHANISM 4 Sheets-Sheet 4 Filed Aug. 25, 1954 wlllllllll 12 INVENTOR Tfzornas K. Zevelq.

G/nm 7(Mm v ATTORNEYS U i ed States Patent MOLD BOX STRIPPING MECHANISM Thomas K. Zevely, Washington, D.C., assignor to 'I he Washington Brick Co., Muirkirk, Md., a corporation of Maryland Application August 23, 1954, Serial No. 451,477

7 Claims. 01. 25-41 This invention relates to block molding machines of the type adapted to automatically produce cored or hollow building blocks of cinder,slag, concrete or similar materials, and is directed primarily to an improved mechanism for stripping such blocks from the compartmented molds in which they are formed.

In lblock molding machines of the type wherein the mold cores are supported by core bars extending across the top of the mold box and the finished blocks are ejected by either raising the mold box relatively tothe block-supporting pallet or lowering the pallet relatively to the mold box, it is customary to engage the tops of the blocks with stripper heads to facilitate the stripping operation and at the same time smooth and compact the upper surfaces of the blocks. In the interest of simplicity, the following description will refer to machines (of the type wherein the mold boxremains stationary and the stripping mechanism and block-supporting pallets ice Patented May 26, 1959 above described which is capable of effectively leveling the tops of the blocks and strip them from the mold.

When the stripper heads are rigidly fixed at their upper ends to the plate by which they are supported and given their vertical movement, the stripper shoes at the lower ends of the heads are always separated by spaces slightly greater than the width of the core bars. that, in such a construction, the moldable block-forming material or aggregate lying directly beneath the core bars is not engaged by the stripper shoes and compressed or packed thereby to the same extent as the rest of the upper faces of the blocks, and when the blocks are cured, cracks or weakened areas frequently 'develop at these points. Even when the cracks or faults do not develop sufliciently to seriously impair the strength of the blocks, the failure of the stripper shoes to engage those portions The result is of the blocks lying beneath the core hars leaves noticeable irregularities in the otherwise smooth surfaces of the blocks. These defects are particularly serious in the case of large .blocks having relatively small numbers of cores and relatively thin walls, and are magnified when the blocks are made of slag and similar materials which plates, because any vertical misalignment of the stripper 3 heads and the elements of the mold box results inundesirable frictional contact therebetween as the stripper heads move up and down; and since the greatestwear occurs at the top of the mold where the stripper heads first come into contact therewith, the upper portions of and compacting the material of the blocks uniformly over the entire area of their upper faces so as to leave no weak points or observable surface irregularities therein which would impair either the strength or the appearance of the blocks. The mechanism of said patent was characterized by the inclusion of pivotally supported stripper heads and means for automatically opening and closing the gaps :between the stripper shoes as the heads move upwardlyand downwardly relative to the mold so as to enable the shoes to pass around the core bars, but

to come together therebeneath and engage the entire upper surfaces of the blocks in the mold during the stripping operation.

The principal object of the present invention is to provide a new and improved stripping mechanism for obtaining substantially the same results as those produced by the patented structure, but Which is simpler in construction, less expensive to manufacture, more positive and reliable in operation, and less expensive to maintain than the mechanism shown in the patent.

' Anotherobject is to provide a novel stripping mechanism wherein the stripper shoes are maintained in separatedpositions at all times other than when they are in contact with the block forming material in the mold box, and are moved into closed positions beneath the core bars by cam members fixed to the liners and division plates of the mold box which are readily replaceable in the event of wear.

A further object is to provide an improved stripping mechanism of the type embodying pivotally suspended stripper heads wherein the heads are normally maintained in inclined positions, with the stripper shoes separated, by the force of gravity, either with or without the aid of spring pressure, and are moved into vertical positions, with the stripper shoes together and in alignment with the mold compartments, by contact with inclined cam surfaces on the mold.

- These and other objects will appear more fully upon it is to 'be expressly understood that these drawings are illustrative only and are not to be construed as representing the-*fullscope of the invention as it is defined in the appended claims.

.Referring now to the drawings, wherein like reference characters indicate like parts throughout the several views:

Figs. 1 and 2 are front and side elevations, respectively, ofone form of stripping mechanism and mold 'box embodyingjthe present invention adapted for use in a wellknown typeof automatic block molding machine, certain parts. havingheen broken away or entirely omitted, and other parts being shown in section, in order to clearly illustrate the essential characteristics of the structure;

Fig; 3 is a plan view of the mold box of Figs. 1 and 2, the core bars and cores being omitted in the right-hand portion of the figure in order to permit an illustration, in

- :broken lines, of the shapes of the stripper shoes and their closed positions when in contact with the blocks in the I I mold; box;

.Fig. 4 is a fragmentary. front view, partially in sectron, of the stripper heads and mold box of Figs. 1-3

showing the elements in the positions occupied when the stripper shoes are in closed positions beneath the core bars, in contact with the blocks;

Fig. 5 is a sectional view on an enlarged scale of the upper end of one of the pivotally supported stripper heads taken substantially on line 55 of Fig. 2;

Fig. 6 is a front view, partially in section, of a modified form of stripping mechanism embodying the present invention showing the stripper heads in the separated positions occupied thereby as they are being lowered toward the mold box; and

Fig. 7 is a fragmentary front view, also partially in section, of the mechanism of Fig. 6 showing the stripper heads in closed positions with the shoes in contact with the blocks in the mold box.

Referring first to Figs. 1, 2 and 3, the stripping mechanism and mold illustrated therein are, except for the improvements constituting the present invention, similar to the corresponding elements shown in my previously mentioned Patent No. 2,566,787, and are adapted for use in the Well-known Besser type of automatic block molding machine wherein hollow or cored blocks are made on plain or imperforate pallets. In such a machine, the blocks are formed in 'a mold 11 which is stationary except for the movements incident to vibration of the mold during the block forming operations, the moldable material being supplied to the mold box through the open top thereof by a horizontally reciprocable feed pan (not shown). During the molding operation, the open bottom of mold box 11 is closed by an imperforate pallet 12, the pallets being fed automatically from a pallet stack to a position below the mold box and then elevated into engagement with the bottom of the mold by vertically reeiprocable anvil bars 13. When the pallet engages with the bottom of the mold, the mold box is elevated slightly so that the transversely extending mold bars 14 which support the mold are out of contact with the portions of the machine framework on which they normally rest. The mold box is then ready to receive the charge of moldable material from the feed pan which moves forwardly over the mold box and delivers the charge by gravity through the open bottom of the pan. During delivery of the charge, the mold box and superposed feed pan are vibrated in known manner.

When the mold has been filled, the feed pan is moved rearwardly clear of the mold box so as to enable the stripping mechanism 15, which is normally maintained in the elevated position indicated in Fig. 1, to descend into contact with the upper surface of the material in the mold to first level and compact said material, during which time the mold box is again vibrated and the

stripper heads

16, 17, 18 are permitted to gradually sink by gravity as the material is compacted, and to then move downwardly through the mold box and positively eject or strip the molded blocks therefrom as the latter are supported on the pallet 12 which is in turn resting on the anvil bars 13. The stripping mechanism ceases its downward movement when the stripper shoes 19, 20, 21 at the lower ends of the stripper heads project slightly below the bottom of the mold box, but the anvil bars 13 continue to descend until the pallet 12 and the blocks supported thereon come to rest on pallet chains (not shown) which advance the loaded pallet to an unloading position, whence the pallet and blocks may be removed from the machine, either manually or automatically, and transported to the curing vault. As the loaded pallet is moved to the unloading position after the stripping operation, the pallet chains automatically bring another empty pallet into position beneath the mold box, and the anvil bars are again elevated to lift the empty pallet into engagement with the bottom of the mold. Simultaneously with the upward movement of the anvil bars, the stripping mechanism 15 is moved upwardly out of the mold box and returned to its initial position illustrated in Fig. 1. The vertical movements of the stripping mechanism and anvil bars, and the cooperative horizontal movements of the feed pan, are controlled in known manner by cams The

stripper heads

16, 17, 18 are supported at their upper ends in a manner hereinafter described by a horizontal plate 22 which is in turn secured to a pair of fore-and-aft bars 23 by bolts 24. The bars 23 are fixed in any suitable manner, as by welding, to the lower edges of a pair of parallel beams 25 which extend from one side of the machine to the other and are connected at their ends to a suitable cam and lever system, such as that shown in my Patent No. 2,566,787, by which the stripping mechanism is given its vertical movements in timed relation to the movements of the feed pan and anvil bars.

In the structure shown in Figs. 1-3, the mold 11 comprises front and

rear side liners

26, 27 and

end liners

28, 29 which form the walls of the mold box and are secured to mold bars 14 in any suitable manner, as by bolts 30. The interior of the mold box may be divided into any desired number of block forming compartments, four in the embodiment illustrated, by means of foreand-aft and

transverse division plates

31, 32 which may be fixed to the mold liners by bolts 33. A tray 34, having its bottom flush with the upper surfaces of

mold liners

26, 27 and

division plates

31, 32 and a vertical rim around all but the rear side thereof, surrounds the upper end of the mold box and is supported on the upper edges of mold bars 14.

In order to form cavities of the desired number and shape in the blocks molded in mold 11, the mold box is provided with a plurality of mold cores 35 which are fixed to and suspended from the lower edges of core bars 36. The core bars extend across the top of the mold box in fore-and-aft directions and are fixed thereto in proper position by clevises 37, the latter being mounted on angle irons 38 welded to mold bars 14 and engaging the ends of the core bars which extend downwardly through openings 39 in tray 34 in known manner. Except for those portions which rest on the upper surfaces of front and

rear side liners

26, 27 and the portions to which cores 35 are connected, the lower edges of core bars 36 overlying the interior of the mold box are positioned well above the upper surfaces of the mold liners and division plates, and also above the normal level of the moldable material in the mold box prior to compaction, and are preferably beveled on one side, as indicated at 40, for a purpose later to be described.

Due to the illustrated arrangement of the elements of mold 11 in such a manner as to simultaneously produce four double cavity blocks on a single pallet, the blocks being arranged in two rows with their longer dimensions parallel to the front of the machine and the core bars 36 extending in fore-and-aft directions, the stripper heads of stripping mechanism 15 are divided into four groups, one group for each block forming compartment of the mold, and each group comprising one fixed head 17 and a pair of

movable heads

16, 18 located on opposite sides of the fixed head.

Each of the fixed stripper heads 17 consists essentially of a vertical plate 41 the upper edge of which is fixed, as by welding, to the bottom of a mounting plate 42 of which there is one for each group of stripper heads. Mounting plates 42 are in turn detachably secured to supporting plate 22 by bolts 43 and nuts 44. The lower end of vertical plate 41 carries a removable stripper shoe 20 which, as indicated in broken lines in Fig. 3, is substantially I-shaped in plan and is adapted to contact the central portion of the upper surface of one of the blocks formed in mold 11. Shoe 20 is adapted to be detachably secured to plate 41 by countersunk bolts 45 and nuts 46 with the portion corresponding to the central stern of the I-shape substantially coplanar with plate 41 and the transversely extending arms projecting on opposite sides of said plate so as to cooperate with the inwardly extending portions of

shoes

19 and 21 of the

movable stripper heads

16 and 18. Inasmuch as stripper shoes 20 of fixed stripper heads 17 have no lateral or horizontal movement relatively to the core bars 36, the edges of said shoes at the ends of the cross arms are vertical and the shoes are so dimensioned that said edges just clear the sides of the core bars during vertical movement of the stripping mechanism.

In order to strengthen the connection between stripper shoe 20 and plate 41, the latter may be provided with enlarged flange portions 47 through which the bolts 45 pass, and with transversely extending steady plates 48 which are welded or otherwise fixed to the outer faces of flanged portions 47 and are of substantially the same length as the cross arms of stripper shoe 20 so as to abut the upper surface of the latter when the shoe is fixed to the head and thereby prevent any tendency of the shoe to rock about the lower edge of head plate 41. The front and rear edges of plates 41 may be recessed, if necessary, for a suitable distance above the outer flanged portions 47, as indicated at 49, to facilitate access to nuts 46.

As shown best in Figs. 1, 2 and 5, each of the

movable stripper heads

16, 18 comprises a vertically extending front end wall 50, a corresponding rear end wall 51, and a side wall 52 which terminates a substantial distance below the upper ends of

end walls

50, 51 and is suitably fixed to the latter, as by welding. Detachably connected to the lower ends of

end walls

50, 51 by countersunk bolts 53 and nuts 54 is a stripper shoe 19 (in the case of stripper head 16) or 21 (in the case of the stripper head 18), the end walls being cut away as indicated at 55 so as to facilitate access to the nuts 54 on the upper ends of bolts 53.

As indicated in broken lines in Fig. 3, each of

stripper shoes

19 and 21 is substantially. C-shaped in plan and is adapted to contact one end portion of the upper surface of one of the blocks formed in mold 11. The free or inboard ends of the arms of each

stripper shoe

19, 21 are beveled as indicated at 56 on the same angle as the beveled portions 40 of core bars 36. This construction not only enables

stripper shoes

19, 21 of the movable stripper heads to come into abutting engagement with the shoes 20 of the fixed stripper heads just as soon as the shoes clear the lower edges of the core bars during downward movement of the stripping mechanism, so as to provide a continuous shoe surface for engagement with the moldable material, but also contributes to uniform filling of the mold since the material 'will flow down the beveled surfaces 40 of the core bars and distribute itself more evenly than if the lower edges of the core bars were of rectangular shape. The sliding contact between the beveled portions of the movable stripper shoes and the core bars also keeps the surfaces free of adhering aggregate which might adversely affect the molding operation.

Each of

movable stripper heads

16, 18 is pivotally suspended from mounting plate 42 by a bolt or spindle 57 having a horizontal axis parallel to core bars 36. The ends of each bolt 57 pass through suitable openings in the front and

rear end walls

50, 51 of the stripper head adjacent the upper ends of said walls, while the portions thereof just inboard of said end walls are journaled in bearings 58 which are housed in recesses in a pair of arms 59 welded to and extending vertically downwardly from the lower surface of mounting plate 42. If desired, each pair of bearing arms 59 may be interconnected by a strengthening plate 60 welded there to and to mounting plate 42.

As indicated in Figs. ,1, 4 and 5, the pivotal axis of each bolt 57 is located in the upper outboard corner of the associated stripper head, above the center of gravity and further than the latter from the cooperating fixed stripper head when the movable head is in the vertical, shoe closed position illustrated in Fig. 4. With this relative positioning of the pivotal axes and centers of gravity of the movable stripper heads, it is evident that, when the stripping mechanism is in an elevated position above the mold 11, each of movable stripper heads 16, 18 normally assumes an inclined position under the force of gravity wherein the inner or beveled edges 56 of

stripper shoes

19, 21 are separated from the adjacent edges of shoes 20 of the fixed stripper head 17, and the lower ends of the movable stripper heads are offset horizontally from the core bars and out of alignment with the mold compartments into which they are adapted to enter.

If desired, means may be provided to supplement the force of gravity for normally maintaining the movable stripper heads 16, 18 in separated position, such as plungers 61 which are slidably housed in recesses 62 formed in the upper edges of front and

rear end walls

50, 51 of each movable stripper head, and compression springs 63 interposed between plungers 61 and the bottoms of recesses 62 which yieldably urge the upper ends of said plungers against the bottom surfaces of mounting plates 42. Plungers 61 are located adjacent the inboard edges of stripper

head end walls

50, 51 so that the thrust of springs 63 acts to move the stripper heads about the axes of pivot bolts 57 in directions to separate

movable stripper shoes

19, 21 from fixed shoes 20. Means may also be provided in the form of set screws 64 for positively limiting the pivotal movement of stripper heads 16, 18 in the shoe opening direction so as to avoid collision between the oppositely moving heads of adjacent groups. As shown best in Fig. 5, set screws 64 pass freely through openings 65 in supporting plate 22 and are threaded through mounting plates 42 and lock nuts 66, being so adjusted that their lower ends abut the upper edges of stripper

head end walls

50, 51 adjacent the outer edges thereof when the stripper heads reach the desired limits of movement.

In the normal elevated position of the stripping mechanism, illustrated in Fig. 1, movable stripper heads 16, 18 are suspended in inclined positions such that the inboard beveled edges 56 of

stripper shoes

19, 21 are separated from the adjacent vertical edges of fixed stripper shoes 20 by distances greater than the width of core bars 36. Consequently, when the stripping mechanism is lowered into the mold, the separated stripper shoes may pass freely around the core bars and the latter may be received in the spaces between the fixed and movable stripper heads above the stripper shoes, which spaces are, of course, wider than the core bars even when the movable stripper heads have been moved to vertical, closed positions in the manner next to be described.

Movable stripper heads 16, 18 are automatically oscillated about the axes of supporting bolts 57, so as to close the stripper shoes, by a structurally simple arrangement of cam members which are mounted on the mold box and so disposed as to be contacted by the movable stripper heads as the stripping mechanisms is lowered into the mold and to positively move said heads about their pivotal axes in directions such as to bring the movable stripper shoes into engagement with the fixed stripper shoes just as downward movement of the stripping mechanism brings the stripper shoes into the plane of the lower edges of core bars 36.

In the embodiment illustrated, best shown in Figs. 1, 3 and 4, the camming means comprises a pair of cam bars 67, 68 mounted on the upper surfaces of

end liners

28, 29 of the mold box, each having a single inclined cam surface 69, and another cam bar 70 mounted on the upper surface of fore-and-aft division plate 31, having a pair of oppositely inclined cam surfaces 71, 72. Cam bars 67, 68, 70 are removably fixed to the mold box in any suitable manner, as by bolts 73 and nuts 74, the bolts passing through openings in the ends of the cam bars and in the underlying portions of mold box tray 34. If desired, each cam bar may also be provided with dowel pins 75 adapted to enter vertically extending holes 76 in the underlying mold liners and division plates so as to assist in maintaining the cam bars in proper position.

As indicated in Fig. l, cam surfaces 69 and 71, 72 of the cam bars have their lower edges coplanar with the vertical surfaces of

end liners

28, 29 and division plate 31 which define the ends of the block forming compartments of the mold, and are so inclined and of such extent that, when the stripping mechanism is lowered with the stripper heads in their normal separated positions, the outboard vertical edges of

stripper shoes

19, 21 of movable stripper heads 16, 18 initially contact the cam surfaces slightly below the upper edges of the latter. As the stripping mechanism continues its downward movement, sliding contact between the outboard edges of

movable stripper shoes

19, 21 and the inclined cam surfaces 69, 71, 72 causes the movable stripper heads to rotate about the pivotal axes of bolts 57 until the movable stripper shoes come into contact with fixed stripper shoes 20 beneath the lower edges of core bars 36. The shoe closing action of the cam members is indicated by the broken line showing in Fig. l of the lower ends of the stripper heads as they pass by the core bars with the beveled edges 56 of the

movable stripper shoes

19, 21 sliding downwardly along the similarly beveled portions 40 of the core bars. When the movable and fixed stripper shoes come into abutment below the core bars, the bottoms of each group of shoes present a substantially continuous surface for contact with the upper surface of the moldable material forming one of the blocks in the mold box, so that when the stripper heads momentarily come to rest on top of the material, and the mold box is vibrated to compact the blocks, the stripper shoes engage substantially the entire area of the top of each block and are thereby capable of exerting a uniform leveling and compacting action, as illustrated in Fig. 4.

After the block forming operation is completed, the stripping mechanism resumes its downward movement and strips the finished blocks from the mold box simultaneously with downward movement of anvil bars 13 and block supporting pallet 12. The stripping mechanism is then elevated to withdraw the stripper heads from the mold box and return them to the initial position of Fig. 1, during which movement the movable stripper heads return to their normal separated positions under the force of gravity, assisted by the resiliency of springs 63 acting through plungers 61, as soon as the outboard edges of

stripper shoes

19, 21 have slid upwardly along cam surfaces 69, 71, 72 and have moved out of contact therewith.

Referring now to Figs. 6 and 7, the modified form of stripping mechanism illustrated therein is particularly adapted for use when the cores and division plates of the mold box are so arranged as to simultaneously produce a single row of three blocks having their longer dimensions in a fore-and-aft direction, similar to the block arrangement illustrated in Figs. 1 and 2 of my previously mentioned Patent No. 2,566,787. In this embodiment of the invention, there are three core bars 77, instead of four as in the structure of Figs. 1-5; two fore-and-aft division plates 31 are used, instead of one; and all of the stripper heads are movable. It will be understood that, except for the specifically different internal arrangement of the mold box and the modified stripper head grouping, the machine represented by Figs. 6 and 7 is of the same construction and mode of operation as that previously described.

The principal ditfci'ence between the two stripper head assemblies is that the heads of Figs. 6 and 7 are arranged in three pairs, one pair to each block, and are all pivotally supported from supporting plate 22 and mounting plates 57, instead of bein divided into four groups, each comprising one fixed head and two movable heads, as in Figs. 1-5. As shown in Fig. 6, there are three pairs of movable stripper heads 16, 18 of the same construction as the movable heads of Figs. 1-5, the heads of each pair being adapted to pass downwardly on opposite sides of one of core bars 77 land to receive the core bar between them during the block compacting and stripping operations. As in the case of the first embodiment, the inboard edges 56 of

stripper shoes

19, 21 are beveled for cooperation with thelower edges of core bars '77. in this instance, however, the core bars are beveled on both sides, as indicated at 78, at the same angles as the beveled portions of the stripper shoes, instead of on one side only.

The cam mechanism of Figs. 6 and 7 for moving the stripper heads into closed position as they pass beneath the core bars is substantially the same as that of Figs. l5, except that two cam bars 70 having double cam surfaces 71, 72 are required, instead of one.

Inasmuch as the method of operation of the modified structure of the second embodiment is the same in all material respects as that previously described, further description thereof should be unnecessary.

The advantages of the improved stripping mechanism of the present invention in comparison with those heretofore embodied in block molding machines of the same general type, including that of my prior Patent No. 2,566,- 787, will be apparent from the foregoing description of the devices illustrated. It will be evident, however, that the invention is not limited to the specific structures shown in the accompanying drawings, but is capable of a variety of mechanical embodiments, and that various changes, which will now suggest themselves to those skilled in the art, may be made in the form, details in construction and arrangement of the parts without departing from the spirit of the invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. In a block molding machine of the type including a mold box containing cores supported by core bars extending across the top of the mold, stripping mechanism for engaging the tops of the molded blocks and means for producing relative movement of the mold box and stripping mechanism to remove the blocks from the box, an improved stripping mechanism comprising a plurality of stripper heads arranged in pairs with the heads of each pair normally separated laterally by a space sufiicient to receive a core bar, means for supporting each pair of stripper heads for lateral movement toward and away from one another, the lower ends of said stripper heads being so shaped and dimensioned that, when in engagement with the tops of the blocks in the mold, the adjacent edges of the lower ends of each pair of heads contact one another in the spaces beneath the core bar which are unoccupied by the cores and said ends engage substantially the entire area of the top of each block, and cam members carried by the mold box for producing lateral movement of said stripper heads during the relative movement of said mold box and stripping mechanism, said cam members being so arranged as to contact the lower ends of said stripper heads as the latter approach the upper surface of said mold box and to move the adjacent edges of each pair of heads into contact beneath the core bar.

2. An improved stripping mechanism according to claim 1 wherein the means for supporting said stripper heads are so arranged that the force of gravity tends to maintain the stripper heads of each pair in laterally separated positions.

3. A stripping mechanism for cored block molding machines of the type including a mold having a plurality of block forming compartments containing cores supported by core bars extending across the top of the mold, comprising a plurality of stripper heads adapted to enter each mold compartment and to engage substantially the entire area of the exposed surface of the moldable material in said compartment, means for producing relative movement between said stripper heads and the mold to bring said heads into engagement with the material in said mold, and means mounted on the mold for contacting at least w some of said stripper heads and producing lateral movement thereof during the relative movement of said stripper heads and mold, said last named means being so positioned as to bring the adjacent edges of the lower ends of the stripper heads associated with each compartment into contact with one another beneath the core bars prior to entry of said heads into said compartment.

4. A stripping mechanism for cored block molding machines of the type including a mold having a plurality of block forming compartments containing cores supported by core bars extending across the top of the mold, com prising a plurality of vertically disposed stripper heads adapted to enter the mold compartments and to engage substantially the entire area of the exposed surface of the moldable material in said compartments, a stripper head supporting member, means for connecting at least some of said stripper heads to said supporting member for pivotal movement about horizontal axes parallel to said core bars, said connecting means being so arranged that the pivotally mounted stripper heads normally occupy inclined positions with their lower ends ofiset horizontally from the core bars and the mold compartments into which they are adapted to enter, means for producing relative movement between said stripper heads and the mold to bring said heads into engagement with the material in said mold, and members mounted on the upper surfaces of said mold having cam surfaces adapted to ,contact portions of the pivotally mounted stripper heads during relative movement of the latter and the mold and to move the lower ends of said stripper heads in a substantially horizontal direction so as to bring them into alignment with the mold compartments beneath the core bars.

5. A stripping mechanism for removing cored blocks from a compartmented mold comprising a plurality of stripper heads adapted to enter the mold compartments and to engage substantially the entire area of the exposed surface of the moldable material in the mold, at least some of said stripper heads normally occupying positions wherein they are ofiset horizontally from the mold compartments into which they are adapted to enter, means for producing relative movement between said stripper heads and the mold to bring said heads into engagement with the material in said mold, and camming means mounted on said mold and so arranged as to be contacted by said normally ofiset stripper heads during said relative movement and to produce movement of said heads in a substantially horizontal direction so as to bring the latter into alignment with the mold compartments.

6. A stripping mechanism according to claim 5 wherein said oamming means are mounted on the upper surfaces of the compartment-forming elements of the mold.

7. A stripping mechanism according toclaim 5 wherein said camming means comprise members mounted on upper surfaces of the mold and having inclined surfaces adapted to be contacted by portions of said normally oil'- set stripper heads.

References Cited in the file of this patent UNITED STATES PATENTS 784,154 Gutteridge et a1. Mar. 7, 1905 1,232,297 Hambuechen July 3, 1917 1,570,618 Cotton Ian. 26, 1926 2,015,980 Walker Oct. 1, 1935 2,319,291 Besser May 18, 1943 2,566,787 Zevely Sept. 4, 1951