Expandable core for casting concrete pipe

Claim 2

A core for casting concrete pipe, comprising: a substantially cylindrical core member, said core member being opened longitudinally along its periphery whereby a slot-like opening is defined in said core member along its longitudinal dimension, said core member being made of a resilient material whereby the width of said slot-like opening and the diameter of said core member may be selectively varied by expanding or contracting said core member; first and second structure mounted on the interior of said core member on opposite sides, respectively, of said slot-like opening; rigid link means having first and second ends, the first end of said link means being pivotally mounted in said first structure; core gate means for closing said slot-like opening, said core gate means being pivotally mounted on one side in said second structure to be pivotal towards or away from said slot-like opening and being pivotally connected at its other side to the second end of said link means whereby said core gate means may be pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slotlike opening or open said slot-like opening and contract said core member; and selectively operable means for pivoting said core gate means towards or away from said slot-like opening.

Claim 3

The invention recited in claim 1, wherein said means for pivoting said core gate means are power driven.

Claim 4

The invention recited in claim 1, wherein said means for pivoting said core gate means are driven by fluid power means.

Claim 5

The invention recited in claim 1, wherein said means for pivoting said core gate means is an overcenter linkage means, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening.

Claim 6

The invention recited in claim 1, wherein said means for pivoting said core gate means includes: overcenter linkage means pivotally connected to said core gate means, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening; and means connected to said overcenter linkage means for selectively driving said overcenter linkage means whereby to pivot said core gate means towards or away from said slot-like opening.

Claim 7

The invention recited in claim 1, including: a gate portion mounted on said core gate means, said gate portion being mounted on said core gate means so as to be pivoted into said slot-like opening whenever said core gate is positioned to close said slot-like opening, said gate portion being of a predetermined width so as to substantially fill said slot-like opening whenever pivoted therein; and gasket means mounted on said core gate means adjacent the sides of said gate portion for sealing said slot-like opening closed.

Claim 8

The invention recited in claim 6, wHerein: the edge of said core member adjacent said first structure and the edge of said gate portion which mates therewith are beveled so that said gate portion may be pivoted into and out of said slot-like opening; and the outer contour of said gate portion is formed to conform with the outer contour of said core member.

Claim 9

A core for casting concrete pipe, comprising: a substantially cylindrical core member, said core member being opened longitudinally along its periphery whereby a slot-like opening is defined in said core member along its longitudinal dimension, said core member being made of a resilient material whereby the width of said slot-like opening and the diameter of said core member may be selectively varied by expanding or contracting said core member; first and second support structure mounted on the interior of said core member on opposite sides, respectively, of said slot-like opening; rigid link means having first and second ends, the first end of said link means being pivotally mounted in said first structure; core gate means for closing said slot-like opening, said core gate means being pivotally mounted on one side in said second structure to be pivotal towards or away from said slot-like opening and being pivotally connected at its other side to the second end of said link means whereby said core gate means may be pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and contract said core member; said first and second support structure establishing a pivot point within said core member relative to said slot-like opening; overcenter linkage means connected between the pivot point established by said support structure and said core gate means for pivoting said core gate means towards or away from said slot-like opening, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening; selectively operable means connected to said overcenter linkage means for driving said overcenter linkage means whereby to selectively expand and close or open and contract said core member.

Claim 10

A core for casting concrete pipe, comprising: a substantially cylindrical core member, said core member being opened longitudinally along its periphery whereby a slot-like opening is defined in said core member along its longitudinal dimension, said core member being made of a resilient material whereby the width of said slot-like opening and the diameter of said core member may be selectively varied by expanding or contracting said core member; first and second support structure mounted on the interior of said core member on opposite sides, respectively, of said slot-like opening; rigid link means having first and second ends, the first end of said link means being pivotally mounted in said first structure; core gate means for closing said slot-like opening, said core gate means being pivotally mounted on one side in said second structure to be pivotal towards or away from said slot-like opening and being pivotally connected at its other side to the second end of said link means whereby said core gate means may be pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and contract said core member; said first and second support structure establishing a pivot point within said core member relative to said slot-like opening; overcenter linkage means connected between the pivot point established by said support structure and said core gate means for pivoting said core gate means towards or away from said slot-like opening, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening; selectively operable means connected to said overcenter linkage means for driving said overcenter linkage means whereby to selectively expand and close or open and contract said core member.

Claim 11

The invention recited in claim 8, wherein said means for driving said core gate means is a fluid means, said fluid means including; fluid cylinder means pivotally mounted on said support structure, said cylinder means having a piston, said piston being connected to said overcenter linkage means; and control means for selectively controlling the operation of said fluid cylinder means.

Claim 12

The invention recited in claim 8, including a gate portion mounted on said core gate means, said gate portion being mounted on said core gate means so as to be pivoted into said slot-like opening whenever said core gate is positioned to close said slot-like opening, said gate portion being of a predetermined width so as to substantially fill said slot-like opening whenever pivoted therein; and gasket means mounted on said core gate means adjacent the sides of said gate portion for sealing said slot-like opening closed.

Claim 13

The invention recited in claim 10, wherein: the edge of said core member adjacent said first structure and the edge of said gate portion which mates therewith are beveled so that said gate portion may be pivoted into and out of said slot-like opening; and the outer contour of said gate portion is formed to conform with the outer contour of said core member.

Claim 14

A core for casting concrete pipe, comprising: a substantially cylindrical core member, said core being opened longitudinally along its periphery whereby a slot-like opening is defined in said core member along its longitudinal dimension, said core member being made of a resilient material whereby the width of said slot-like opening and the diameter of said core member may be selectively varied by expanding or contracting said core member; first aNd second mounting structure mounted on the interior of said core member on opposite sides, respectively, of said slot-like opening; rigid link means having first and second ends, the first end of said link means being pivotally mounted in said first mounting structure; core gate means for closing said slot-like opening, said core gate means being pivotally mounted on one side in said second mounting structure to be pivotal towards or away from said slot-like opening and being pivotally connected at its other side to the second end of said link means whereby said core gate means may be pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and contract said core member; said first and second mounting structures including first and second support members pivotally connected to each other at a predetermined point relative to said slot-like opening within said core member; overcenter linkage means connected between said support members at their pivotal point of connection and said core gate means for pivoting said core gate means towards or away from said slot-like opening, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening; a fluid cylinder means pivotally mounted on said first support member, said cylinder means having a piston, said piston being connected to said overcenter linkage means for driving said overcenter linkage means whereby to expand and close or open and contract said core member; and control means for selectively controlling the operation of said fluid cylinder means whereby to control the movement of said piston connected to said overcenter linkage means.

Claim 15

A core for casting concrete pipe, comprising: a substantially cylindrical core member, said core being opened longitudinally along its periphery whereby a slot-like opening is defined in said core member along its longitudinal dimension, said core member being made of a resilient material whereby the width of said slot-like opening and the diameter of said core member may be selectively varied by expanding or contracting said core member; first aNd second mounting structure mounted on the interior of said core member on opposite sides, respectively, of said slot-like opening; rigid link means having first and second ends, the first end of said link means being pivotally mounted in said first mounting structure; core gate means for closing said slot-like opening, said core gate means being pivotally mounted on one side in said second mounting structure to be pivotal towards or away from said slot-like opening and being pivotally connected at its other side to the second end of said link means whereby said core gate means may be pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and contract said core member; said first and second mounting structures including first and second support members pivotally connected to each other at a predetermined point relative to said slot-like opening within said core member; overcenter linkage means connected between said support members at their pivotal point of connection and said core gate means for pivoting said core gate means towards or away from said slot-like opening, said overcenter linkage means being operable to lock said core member in an expanded position with said core gate closing said slot-like opening; a fluid cylinder means pivotally mounted on said first support member, said cylinder means having a piston, said piston being connected to said overcenter linkage means for driving said overcenter linkage means whereby to expand and close or open and contract said core member; and control means for selectively controlling the operation of said fluid cylinder means whereby to control the movement of said piston connected to said overcenter linkage means.

Claim 16

The invention recited in claim 12, including: a gate portion mounted on said core gate means, said gate portion being mounted on said core gate means so as to be pivoted into said slot-like opening whenever said core gate is positioned to close said slot-like opening, said gate portion being of a predetermined width so as to substantially fill said slot-like opening whenever pivoted therein and having an outer contour formed to conform with the outer contour of said core member, the edge of said core member adjacent said first mounting structure and the edge of said gate portion which mates therewith being beveled so that said gate portion is pivotal into and out of said slot-like opening; and gasket means mounted on said core gate means adjacent the sides of said gate portion for sealing said slot-like opening closed.

Claim 17

In a core for casting concrete pipe, wherein a cylindrical core member having a longitudinal slot-like opening in its periphery is selectively expanded and said slot-like opening closed so concrete pipe may be cast therearound, the improvement of means for selectively expanding said core member while simultaneously closing said slot-like opening comprising: core gate means for closing said slot-like opening; rigid link means having first and second ends, said rigid link means having its first end pivotally connected to one side of said core gate means; means pivotally mounting the other side of said core gate means and means pivotally mounting the second end of said link means on the interior of said core member on opposite sides, respectively, of said slot-like opening whereby the combination of said core gate means and said link means straddles said slot-like opening and said core gate means may be selectively pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and collapse said core member; and selectively operable means for pivoting said core gate means towards or away from said slot-like opening.

Claim 18

In a core for casting concrete pipe, wherein a cylindrical core member having a longitudinal slot-like opening in its periphery is selectively expanded and said slot-like opening closed so concrete pipe may be cast therearound, the improvement of means for selectively expanding said core member while simultaneously closing said slot-like opening comprising: core gate means for closing said slot-like opening; rigid link means having first and second ends, said rigid link means having its first end pivotally connected to one side of said core gate means; means pivotally mounting the other side of said core gate means and means pivotally mounting the second end of said link means on the interior of said core member on opposite sides, respectively, of said slot-like opening whereby the combination of said core gate means and said link means straddles said slot-like opening and said core gate means may be selectively pivoted towards or away from said slot-like opening, respectively, to expand said core member and close said slot-like opening or open said slot-like opening and collapse said core member; and selectively operable means for pivoting said core gate means towards or away from said slot-like opening.

Claim 19

The invention recited in claim 14, wherein said means for pivoting said core gate means includes an overcenter linkagE means connected to said core gate means, said overcenter linkage means being operable to lock said core member in an expanded position with said slot-like opening closed by said core gate means.

Claim 20

The invention recited in claim 14, wherein said means for pivoting said core gate means includes: overcenter linkage means connected to said core gate means, said overcenter linkage means being operable to lock said core member in an expanded position with said slot-like opening closed by said core gate means; and fluid means connected to said overcenter linkage means for selectively driving said overcenter linkage whereby to pivot said core gate means toward or away from said slot-like opening.