US3687412A

US3687412A - Concrete slab mold

Info

Publication number: US3687412A
Application number: US37778A
Authority: US
Inventors: George Alfred Vaughan; William Lawrence Dunn
Original assignee: Davy Loewy Ltd
Current assignee: Davy Loewy Ltd
Priority date: 1969-05-16
Filing date: 1970-05-15
Publication date: 1972-08-29
Anticipated expiration: 1989-08-29
Also published as: JPS4943258B1; GB1305191A; DE2023531A1

Abstract

A mould suitable for use in concrete moulding apparatus in which concrete held in the mould is subjected to a pressing action, the mould consists of a base on which a plurality of edge members are mounted to define an enclosure for the concrete. At least one of the members which constitutes one side of the enclosure is held in position on the base by at least two struts in the form of screw jacks. The struts are connected to the member and releasably anchored to the base outside of the enclosure. It is preferred for all the struts associated with each edge member to be so arranged that the struts can be simultaneously released from the mould base without adjusting the length of the struts.

Description

United States Patent Vaughan et al.

[ 1 Aug. 29, 1972 [54] CONCRETE SLAB MOLD [72] Inventors: George Alfred Vaughan; William Lawrence Dunn, both of Sheffield, England [73] Assignee: Davy and United Engineering Company Limited, Yorkshire, England 22 Filed: May 15,1970

21 Appl.No.: 37,778

[30] Foreign Application Priority Data May 16, 1969 Great Britain ..25,083/69 [52] US. Cl ..249/158, 25/45 [51] Int. Cl. ..B28b 7/02 [58] Field of Search ..249/158, 162, 164, 168, 155, 249/163, 167, 82,161, 120,131,128, 124,

[56] References Cited UNITED STATES PATENTS 2,590,478 3/1952 Weinberg ..25/119 x 3,340,926 9/1967 Sylvester ..249/158 x Frerichs ..25/101 Stieler ..25/128 K 890,466 6/1908 7 3,373,460 3/1968 Ladney ..25/128 K 3,286,973 1 1/1966 Sylvester ..249/82 955,282 4/1910 Pocock ..249/158 3,292,216 12/1966 Colombo ...249/l 58 X Primary Examiner-J. Spencer Overholser Assistant Examiner-John S. Brown Att0rneyHolcombe, Wetherill & Brisebois [57] ABSTRACT the base outside of the enclosure. It is preferred for all the struts associated with each edge member to be so arranged that the struts can be simultaneously released from the mould base without adjusting the length of the struts.

11 Claims, 7 Drawing Figures I PATENTEDnusze I972 sun-:12 or 3 PATENTEnAum 1912 SHEEI a or 3 -w Y J Q E Q CONCRETE SLAB MOLD This invention relates to concrete moulding apparatus and in particular to the construction of suitable moulds for such apparatus. The invention is applicable to concrete presses in which a slab or other body of concrete mixture is held in a mould and is subjected to a pressing action.

An object of the present invention is to provide a design of mould which is readily adjustable in size.

In accordance with the present invention a mould for concrete moulding apparatus comprises a mould base, a plurality of elongate edge members arranged on the base to define an enclosure for receiving the material to be moulded, and wherein at least the member constituting one side of the enclosure is held in position on the base by at least two extensible struts connected to the member and releasably anchored to the base outside of the enclosure.

Although all of the edge members may be held in position on the base by means of extensible struts, where the edge members define a generally rectangular enclosure, the members constituting a pair of adjacent sides of the enclosure may be held in position on the base by means of the extensible struts.

If an edge member which has struts associated therewith is in two or more parts arranged in end-toend relation, then each part has at least two struts associated therewith.

The struts are conveniently releasably anchored to an upstanding member rigidly secured to the mould base.

It is preferred that each strut is releasably anchored to its upstanding member by means which include cooperating tapered wedge surfaces on the strut and the upstanding member which permit the strut to be released from or anchored to the upstanding member without adjusting the length of the strut. All the struts associated with an edge member are conveniently connected together so that the struts can be released from or anchored to the upstanding member substantially simultaneously.

The struts may be adjustable incrementally as by adding or taking away units which together constitute the strut. However, it is preferable for the struts to be adjustable steplessly and the struts may comprise hydraulic rams or screw jacks.

In one embodiment of the invention each strut comprises a tubular member pivotally connected at one end to a mould edge member, a nut operatively coupled to the other end of the tubular member so as to be rotatable relative thereto and about the same axis as the tubular member, and a screw which is engageable with the nut and which in use is anchored to the mould base. By rotating the nut, the mould edge member is adjustable relative to the mould base. If it is desired to adjust the mould edge member by a distance which is greater than that possible by the screw and nut adjustment then additional tubular members may be inserted between the nut and the tubular member which is connected to the mould edge member.

Means for anchoring the screw to the mould base comprises an upstanding member fixed to the mould base, the member having a recess for receiving the screw and the member and the screw having co-operating tapered wedge surfaces provided thereon. The angle of the taper is such that the pressure acting outwards against the mould edge during moulding can be withstood without the screw being forced out of the recess in the upstanding member. Also the wedge surfaces permit the strut to be anchored to or released from the upstanding member without adjusting the length of the strut.

In an alternative embodiment of the invention each strut comprises a tubular member secured at one end to a mould edge and having an internally threaded portion at its opposite end which serves as a nut. A screw is associated with the nut and the end of the screw away from the mould edge is rotatably and releasably anchored to a member upstanding from the mould base. By rotating the screw the tubular member is displaced along the screw thereby adjusting the position of the mould edge on the mould base. Similarly by providing wedge surfaces on the screw and the upstanding member, the screw can be anchored to or released from the member without adjusting the length of the strut.

In order that the invention may be more readily understood it will now be described, by way of example only, with reference to the accompanying drawings numbered consecutively in which:

FIG. 1 is a plan view of a mould, in the upper half of FIG. 1 the mould is positioned at its maximum size and in the lower half of FIG. 1 the mould is of reduced size,

FIG. 2 is a cross-sectional elevation on the line IIII of FIG. 1,

FIG. 3 is a side elevation illustrating an alternative means to that shown in FIG. 2 for anchoring the struts to the mould base,

FIG. 4 illustrates in cross-section a third means of coupling tubular members together,

FIG. 5 is a sectional side elevation of an alternative form of strut,

FIG. 6 is a sectional elevation on the line VIVI of FIG. 5, and

FIG. 7 is a plan of the strut shown in FIGS. 5 and 6.

Referring to FIG. 1, an adjustable mould for moulding panels in concrete comprises a mould base 13 to which a grating 14 of known construction is secured. Two pairs of

mould edge members

15, 16 are arranged on the grating to define an enclosure for receiving the mouldable material. The spaced-apart pair of mould edges 15 are arranged at right-angles to the pair of mould edges 16 and each mould member is held in' position by means of a plurality of extensible struts 17 each connected at one end to the edge member and anchored at the other end to the mould base by means to be described in greater detail hereinafter.

Referring now to FIG. 2, the extensible strut 17 is in the form of a screw jack comprising a tubular member 18 pivotally connected at one end to a pivot 19 carried by brackets 20 secured to the edge member. The axis of the pivot pin 19 is horizontal and the strut can pivot about the pin in a vertical plane. Alternately the axis of the pin could be vertical. A nut 21 is secured to the free end of the tubular member 18 so as to be rotatable relative to and coaxial with the tubular member. The nut is coupled to the tubular member with an end portion of the nut projecting into a cut-away portion at the end of the tubular member. The nut is permitted to rotate within the tubular member and three set screws 22 extend through openings in the tubular member positioned 120 apart around the periphery thereof and project into a groove 23 provided in the nut. The inner periphery of the nut 21 is threaded and a threaded portion 25 at one end of a screw 26 engages with the nut and the length of the threaded portion of the screw is substantially equal to the overall length of the tubular member 18.

The non-threaded portion of the screw 26 is non rotatably carried in an upstanding U-shaped recess 27 formed in an anchor member 28 which is secured, by welding, to the mould base 13. A pair of

wedge members

30 and 31 have co-operating tapered surfaces and form part of the member 28 and the screw 26 respectively. The wedge member 30 is in two parts one on each side of the recess 27 and the wedge member 31 is of generally inverted U-shape with the limbs thereof positioned on opposite sides of the screw 26. The angle of the taper is so arranged that pressure acting outwards against the mould edge during moulding is transmitted to the member 28 through the strut without the screw 26 being forced upwardly out of the recess 27. The mould edge member 15 can however be stripped from the mould part simply by pivoting the strut 17 upwards about the pin 19 until the

wedges

30 and 31 are released and then withdrawing the edge member away from the moulded part. In order to simplify the removal of each

mould edge member

15 or 16 from the moulded part, the ends of all the screws 26 which are associated with a particular mould edge member are connected together by means of a draw bar 35. The struts can be pivoted about the mould edge member to anchor or release the struts simply by raising or lowering the draw bar 35.

In FIGS. 1 and 2 the upstanding members 28 to which the mould edge members 15 are connected have a series of spaced-apart recesses 27 formed therein. The struts 17 of the mould edge members 15 are anchored in use and it is convenient for the edge members 15 to extend for substantially the entire length of the mould irrespective of the length of the panel to be moulded. In order to vary the width of a part to be moulded the mould edge members 15 are moved towards and away from each other and to vary the length of the part to be moulded the mould edge members 16 are displaced relative to the adjacent edge of the mould base 13. The mould edge members 16 are interchanged for another pair of members when it is necessary to alter the width of the mould.

For convenience the anchor posts 28 for the struts 17 may be movably secured to the mould base. To this end, (see FIG. 3), the anchor member 28 is secured to an anchor plate 38 which is provided on its underside with a key 39 which is located in a key-way 40 in the mould base 13. In addition set screws 41 project through the anchor plate and engage tapped holes in the mould base so as to secure the anchor plate to the mould base.

To adjust each

mould edge member

15, 16 relative to its adjacent edge of the mould base 13, the nut 21 of each strut associated with the member is rotated causing it to travel along the screw 25 thereby displacing the tubular member 18 and the associated mould edge member. The nut 21 is rotated by means of a tommy bar inserted in one of three holes 44 provided at 120 apart around the periphery of the nut.

If the displacement permitted by the screw and nut adjustment of each strut 17 is insufficient then additional tubular members 46 are inserted as required between the nut 21 and the tubular member 18. FIG. 4 shows the preferred means of coupling an additional member 46 to the member 18. In the figure, a connecting piece 47 is inserted between the adjacent ends of the tubular members 18 and 46. The connecting piece 47 has a continuous groove 48 in which the reduced ends of three set screws 49 are located so that the connecting piece can rotate relative to the member 18. The member 46 can be coupled to the connecting piece either by set screws engaging tapped holes in the piece 47 or the set screws being located in grooves; it is immaterial whether there is relative rotation between the member 46 and the piece 47.

To speed up the insertion of the additional tubular members 46, the members 46 are inserted in pairs, the members of each pair being spaced fixedly apart by means of diagonal braces 50 as shown in FIG. 1.

In an alternative form of strut shown in FIGS. 5 to 7 a tubular member 60 is secured to an edge member 15 and the opposite end of the tubular member is threaded at its inner periphery and a threaded part 62 of a screw 64 engages with the threads. The screw is rotatable in a bush 66 secured in one end of a tubular member 68 which surrounds part of the tubular member 60. A set screw in the member 68 projects into an axial groove 69 in the member 60 to prevent rotation of the member 68.

The strut is anchored at its end away from the edge member by means of a housing 70 which entends along one edge of the mould base and is keyed thereto to prevent movement between the housing and the mould base. The housing is of generally box-like construction having a front wall 72 with apertures 74 therein through at least some of which the tubular struts project. The upper portion of the housing has an opening 76 extending along the length thereof and an elongate member in the form of a bar 78 is positioned in the opening. The underside of the bar is provided at intervals, which correspond with the separation of the struts, with downwardly depending portions 80 which can be brought into engagement with a lug 82 on the tubular members 68 of each strut. Co-operating wedge surfaces are provided on the lug 82 and portions 80.

To operate the strut the screw 64 is rotated driving the inner tubular member 60 axially to adjust the length of the struts and when the mould is in use the thrust on the side walls is taken by the lug 82 acting against the wedge on the bar 78. To release the struts the bar is displaced axially to a position where the wedge surface on the portion 80 is out of engagement with the wedge surface on the lug 82. As the wedges surfaces on the portions 80 associated with the struts secured to one edge member are all provided on one bar 78, the struts can all be released simultaneously by one axial movement of the bar.

In all the embodiments of the invention, the

mould edge members

15, 16 are provided with upstanding extensions (not shown). When the mould is introduced into the moulding press, the mould is filled with concrete almost to the top of the entensions and during moulding the extensions are pressed by a press platen to reduce the height of the mould edge members as the concrete is pressed in the mould.

' We claim:

l. A mould for concrete moulding apparatus comprising a flat base member, a plurality of elongate mould edge members securely positioned on the base member to define therewith an open-topped enclosure for receiving the material to be moulded, at least the edge member constituting one side of the enclosure being securely positioned on the base member by at least two struts each extending substantially normal to the edge member and to an upstanding member rigidly secured to the mould base member at a position outside of the enclosure, each strut being of adjustable length and pivotally connected at one end to the edge member and anchored at its other end to the upstanding member by means including cooperating tapered wedge surfaces on the strut and the upstanding member which permit the strut to be released from or anchored to the upstanding member without adjusting the length of the strut.

2. A mould for concrete moulding apparatus comprising a flat base member, a plurality of elongate mould edge members securely positioned on the base member to define therewith an open-topped enclosure for receiving the material to be moulded, at least the edge member constituting one side of the enclosure being securely positioned on the base member by at least two extensible struts each extending substantially normal to the edge member and to an upstanding member rigidly secured to the mould base member at a position outside of the enclosure, each strut being in the form of a screw jack having a part including a nut and a part comprising a screw which is associated with the nut, one of said parts being pivotally secured to the edge member and the other part releasably anchored to the upstanding member, said other part and said upstanding member having co-operating tapered wedge surfaces which by causing relative movement therebetween permit the strut to be released from or anchored to the upstanding member without adjusting the length of the strut.

3. A mould as claimed in claim 1 in which the edge the edge members constituting one pair of adjacent sides are each held in position on the base by means of said extensible struts.

4. A mould as claimed in claim 1 wherein at least one of the edge members having struts associated therewith is in at least two parts arranged in end-to-end relation and each part has at least two struts associated therewith.

5. A mould as claimed in claim 1 wherein all the struts associated with an edge member are connected together so that the struts can be released from or anchored to the upstanding member substantially simultaneously.

6. A mould as claimed in claim 2 wherein the tapered wedge surfaces on the upstanding member to which the struts are anchored are provided on a member displaceable with respect to the upstanding member so that the struts can be released from or anchored to the upstanding member substantially simultaneously.

7. A mould as claimed in claim 1 wherein each extensible strut comprises a hydraulic ram.

8. A mould as claimed in claim 2 wherein each strut comprises a ,tubular member having a nut rotatably coupled to one end and a screw coaxial with the tubular member and in en a 'ement with the n t.

9. A mould as cqal med in claim 2w erein each strut comprises a tubular member internally threaded at one end, a screw in engagement with the threads on the tubular member and rotatably mounted in a further tubular member surrounding said first-mentioned tubular member. A

10. A mould as claimed in claim 8 wherein the end of the tubular member away from the nut is pivotally secured to an edge member and the end of the screw away from the edge member is anchored to the base.

11. A mould as claimed in claim 8 in which the tubular member is pivotable with respect to the edge member about a horizontal axis.

Claims

1. A mould for concrete moulding apparatus comprising a flat base member, a plurality of elongate mould edge members securely positioned on the base member to define therewith an open-topped enclosure for receiving the material to be moulded, at least the edge member constituting one side of the enclosure being securely positioned on the base member by at least two struts each extending substantially normal to the edge member and to an upstanding member rigidly secured to the mould base member at a position outside of the enclosure, each strut being of adjustable length and pivotally connected at one end to the edge member and anchored at its other end to the upstanding member by means including cooperating tapered wedge surfaces on the strut and the upstanding member which permit the strut to be released from or anchored to the upstanding member without adjusting the length of the strut.

3. A mould as claimed in claim 1 in which the edge members define a generally rectangular enclosure and the edge members constituting one pair of adjacent sides are each held in position on the base by means of said extensible struts.

8. A mould as claimed in claim 2 wherein each strut comprises a tubular member having a nut rotatably coupled to one end and a screw coaxial with the tubular member and in engagement with the nut.

9. A mould as claimed in claim 2 wherein each strut comprises a tubular member internally threaded at one end, a screw in engagement with the threads on the tubular member and rotatably mounted in a further tubular member surrounding said first-mentioned tubular member.