Barrel forming press

Claim 2

A press apparatus for successively bending to a desired shape presented portions of a metal workpiece at successive points displaced longitudinally along the work piece during longitudinal movement thereof, said apparatus comprising in combination: a. a Work piece die means adapted for supporting said work piece, said die means comprising a first portion having a constant inclined slope and including a feed surface, and a second portion having a substantially concave surface, which is immediately adjacent and tangentially contiguous to said first portion; b. feed means for incrementally advancing said work piece on said feed surface toward said second portion whereby said work piece is supported by a first support point on said first portion and a second support point on said second portion; c. mandrel means movably disposed adjacent said second portion of said die means and adapted to reciprocate along an axis to predetermined positions relative thereto, to engage and cause deformation of the stock portions; d. mandrel support means disposed adjacent to said second portion and secured to said mandrel means; and, e. power means for selectively moving said mandrel support means in a direction parallel to the axis of reciprocal movement of said mandrel means.

Claim 3

A press apparatus as defined in claim 1 wherein said mandrel means, in longitudinal cross-section, is convex in form relative to said second portion of said die means, and wherein for each stock advancement in initial point of engagement of said mandrel means with the stock is distal to the longitudinal center line, of said mandrel, while continued downward movement in deforming the stock portions causes the relative engagement point to approach the longitudinal center line of said mandrel means.

Claim 4

A press apparatus as defined in claim 1 wherein said second portion of said die means is of constant-curvature form and wherein said axis of mandrel movement is coincident with a radial axis of said second portion.

Claim 5

A press apparatus as defined in claim 3 wherein said die means includes a third portion, said third portion having a constant slope and being tangentially contiguous with said second portion of said die means at the opposite end thereof from said first portion.

Claim 6

A press apparatus as defined in claim 3 wherein the angle subtended by the plane of said first portion of said die means and said axis of mandrel movement is substantially 15 1/2 *.

Claim 7

A press apparatus for longitudinally bending to a desired curvature a portion of metal stock said apparatus comprising in combination: a. die means, said die means being longitudinally concave in form and adapted to provide support for the stock portions at the longitudinal ends thereof, wherein a portion of said die means is of uniform curvature; b. mandrel means movably disposed adjacent said uniform curvature portion of said die means, and adapted to reciprocate along a radial axis of said uniform curvature portion to predetermined positions relative thereto, to engage and cause deformation of the stock portion; c. pulldown means secured to said mandrel means and adapted to provide support therefor; d. power means for selectively moving said pulldown means in a direction parallel to the axis of reciprocal movement of said mandrel means; e. sensing means disposed on said axis of reciprocal movement and responsive to determine the displacement of the stock portion along said axis of reciprocal movement in relation to a fixed plane normal to said axis; f. comparing means adapted to receive a pre-registered desired displacement value and to compare it with the actual displacement of the stock portion as determined by said sensing means; g. feedback means for actuating said power means in response to said comparing means; h. wherein the actual displacement of the stock portion is compared with a pre-registered desired displacement and additional deforming is accomplished until the two values become comparable.

Claim 8

A press apparatus for longitudinally bending to a desired curvature a portion of metal stock said apparatus comprising in combination: a. die means, said die means being longitudinally concave in form and adapted to provide support for the stock portions at the longitudinal ends thereof, wherein a portion of said die means is of uniform curvature; b. mandrel means movably disposed adjacent said uniform curvature portion of said die means, and adapted to reciprocate along a radial axis of said uniform curvature portion to predetermined positions relative thereto, to engage and cause deformation of the stock portion; c. pulldown means secured to said mandrel means and adapted to provide support therefor; d. power means for selectively moving said pulldown means in a direction parallel to the axis of reciprocal movement of said mandrel means; e. sensing means disposed on said axis of reciprocal movement and responsive to determine the displacement of the stock portion along said axis of reciprocal movement in relation to a fixed plane normal to said axis; f. comparing means adapted to receive a pre-registered desired displacement value and to compare it with the actual displacement of the stock portion as determined by said sensing means; g. feedback means for actuating said power means in response to said comparing means; h. wherein the actual displacement of the stock portion is compared with a pre-registered desired displacement and additional deforming is accomplished until the two values become comparable.

Claim 9

The press apparatus as defined in claim 6 including a feed means adapted to present successive longitudinal portions of stock for successive longitudinal bending thereof, wherein the displacement of each of said successive longiTudinal portions is determined by said sensing means in relation to the same fixed plane.

Claim 10

The press apparatus as defined in claim 6 wherein said pulldown means comprises a pair of spaced pulldown members having aligned passages formed therein for receiving said mandrel means extending normally therebetween, and wherein said sensing means is disposed in one of said passages adjacent the top surface of said mandrel means so as to be responsive to upward movement of said mandrel means relative to said pulldown means.

Claim 11

A press apparatus for successively bending to a desired shape presented portions of metal stock during longitudinal movement thereof, said apparatus comprising in combination: a. a planar table adapted to support the stock during its longitudinal movement thereover; b. feed means for progressively advancing the stock at predetermined increments along said table; c. a longitudinally concave die comprising a first portion of constant slope communicating with, and coincident with the plane of, said planar table, and a second portion having a substantially concave configuration adapted to slidably receive and frictionally engage along a line thereon, the stock for which it provides support, the position of the line of engagement varying longitudinally as the stock is advanced along its path; d. pulldown means movably disposed adjacent said die; e. a first mandrel secured to said pulldown means, said first mandrel being disposed above said second portion of said die means and adapted to move toward said die in a radial axis of said second portion; f. power means operably connected to said pulldown means for moving said first mandrel to predetermined positions relative to said second surface of said die.

Claim 12

A press apparatus for successively bending to a desired shape presented portions of metal stock during longitudinal movement thereof, said apparatus comprising in combination: a. a planar table adapted to support the stock during its longitudinal movement thereover; b. feed means for progressively advancing the stock at predetermined increments along said table; c. a longitudinally concave die comprising a first portion of constant slope communicating with, and coincident with the plane of, said planar table, and a second portion having a substantially concave configuration adapted to slidably receive and frictionally engage along a line thereon, the stock for which it provides support, the position of the line of engagement varying longitudinally as the stock is advanced along its path; d. pulldown means movably disposed adjacent said die; e. a first mandrel secured to said pulldown means, said first mandrel being disposed above said second portion of said die means and adapted to move toward said die in a radial axis of said second portion; f. power means operably connected to said pulldown means for moving said first mandrel to predetermined positions relative to said second surface of said die.

Claim 13

A press apparatus as defined in claim 9 wherein said radial axis along which said first mandrel moves is in a vertical plane and said planar table is inclined to substantially 15 from the horizontal plane, with the lower end of said planar table being integrally secured to said die.

Claim 14

A press apparatus as defined in claim 9 and including means for retracting said first mandrel in a direction transverse to both the longitudinal axis of said table and said radial axis, to retract said first mandrel to one longitudinal side of said table and die and permit removal of a deformed work piece.

Claim 15

A press apparatus as defined in claim 11 wherein said pulldown means comprises first and second, spaced vertically aligned pulldown members, one disposed on each side of said die, said pulldown members having aligned passages formed therein for engagably receiving said first mandrel extending normally therebetween, said first mandrel being retractable along the axis of said passages to disengage said second pulldown members and extend outwardly from said first pulldown member on the longitudinal side opposite said die.

Claim 16

A press apparatus as defined in claim 12 and including: a. a second mandrel adapted to extend normally between said first and second pulldowns and to be engagably received in said passages formed therein when said first mandrel is in a retracted position, said second mandrel being adapted to move toward said die in a radial axis of said second portion thereof; b. and means for retracting said second mandrel along the axis of said passages to disengage said first pulldown member and extend outwardly from said second pulldown member on the longitudinal side opposite said die.

Claim 17

A press apparatus as defined in claim 9 and including a guide mechanism adjacent said die and opposite said table with respect to said pulldown means, said guide mechanism comprising: a. a transverse track aligned transversely to both the longitudinal axis of said table and said radial axis; b. a pair of spaced, longitudinal, fingers adapted to be moved along said transverse track, said fingers having oppositely disposed contact surfaces thereon, said contact surfaces being adapted to engage oppOsite longitudinal edges of a metal stock piece near the leading end thereof; c. a pair of biasing means for biasing said fingers inwardly toward each other on said track to engage and move the stock leading end to longitudinally align the metal stock with respect to said table; d. means for pre-aligning one of said fingers with respect to a longitudinal side of said table; and e. means for releasing said pair of biasing means to allow said fingers to disengage from the stock piece and permit the stock piece to be advanced longitudinally along said table.

Claim 18

A press apparatus as defined in claim 14 wherein one of said pair of biasing means is substantially unequal in biasing force to the other one of said pair to biasing means and wherein the force of one biasing means is completely overcome by the force of the opposite biasing means, wherein the finger connected to the weaker biasing means is permitted to initially engage said stock piece while at one position on the transverse track and to subsequently be moved to said pre-aligned position on said track.

Claim 19

A press apparatus as defined in claim 9 wherein said feed means is adjacent to said planar table and comprises: a. a transverse track aligned transversely to both the longitudinal axis of said table and said radial axis; b. a pair of spaced jaws adapted to be moved along said transverse track, said jaws having opposing spurs thereon said spurs being adapted to engage opposite longitudinal edges of a metal stock piece near the trailing and thereof; c. a pair of biasing means for biasing said jaws inwardly toward each other on said track to engage and move the stock trailing end to longitudinally align the metal stock with respect to said table; d. means for pre-aligning one of said jaws with respect to a longitudinal side of said table; e. means for moving said track longitudinally on said table, toward said pulldown means, so as to maintain alignment of said stock piece; and f. means to release said jaws from engagement with said stock piece when the trailing edge of the stock piece approaches said pulldown means.

Claim 20

A press apparatus as defined in claim 16 wherein one of said pair of biasing means is substantially unequal in biasing force to the other one of said pair of biasing means and wherein the force of one biasing means is completely overcome by the force of the opposite biasing means, wherein the jaw connected to the weaker biasing means is permitted to initially engage said stock piece while at one position on the transverse track and to subsequently be moved to said pre-aligned position on said track.

Claim 21

A press apparatus as defined in claim 14 wherein said feed means is adjacent to said planar table and comprises: a. a transverse track aligned transversely to both the longitudinal axis of said table and said radial axis; b. a pair of spaced jaws adapted to be moved along said transverse track, said jaws having opposing spurs thereon said spurs being adapted to engage opposite longitudinal edges of a metal stock piece near the trailing and thereof; c. a pair of biasing means for biasing said jaws inwardly toward each other of said track to engage and move the stock trailing end to longitudinally align the metal stock with respect to said table; d. means for pre-aligning one of said jaws with respect to a longitudinal side of said table; e. means for moving said track longitudinally on said table, toward said pulldown means, so as to maintain alignment of said stock piece; and f. means to release said jaws from engagement with said stock piece when the trailing edge of the stock piece approaches said pulldown means; wherein said pre-aligning means for said feed means is coordinated with said pre-aligning means for said guide mechanism to align one longitudinal edge of a stock piece with a longitudinal side of said table.

Claim 22

A press apparatus for forming regular polygon barrels approximating a cylinder by progressivelY bending presented portion of flat metal stock during longitudinal movement thereof, the apparatus comprising in combination: a. feed means for advancing the stock predetermined increments along a longitudinal path; b. a die surface adapted to provide two support points for frictional engagement and support of the stock portions at the longitudinal ends thereof, said support points varying over the longitudinal length of said die surface as the stock is advanced; c. a mandrel movably disposed adjacent said die surface and adapted to reciprocate to pre-determined positions relative thereto, to engage and cause deformation of the stock portions; d. pulldown means secured to said mandrel means and adapted to provide support therefor; e. power means for selectively moving said pulldown means in a direction parallel to the axis of reciprocal movement of said mandrel means; f. means for preselecting said increments of stock advancement for a particular diameter barrel; and g. means for preselecting particular mandrel positions corresponding to the particular advancement positions of the stock along said longitudinal path; wherein the diameter of the cylindrical elements is determined by selection of a particular stock advancement interval and of particular mandrel positions in relation to the advancement positions of the stock along said longitudinal path.

Claim 23

A press apparatus for forming regular polygon barrels approximating a cylinder by progressivelY bending presented portion of flat metal stock during longitudinal movement thereof, the apparatus comprising in combination: a. feed means for advancing the stock predetermined increments along a longitudinal path; b. a die surface adapted to provide two support points for frictional engagement and support of the stock portions at the longitudinal ends thereof, said support points varying over the longitudinal length of said die surface as the stock is advanced; c. a mandrel movably disposed adjacent said die surface and adapted to reciprocate to pre-determined positions relative thereto, to engage and cause deformation of the stock portions; d. pulldown means secured to said mandrel means and adapted to provide support therefor; e. power means for selectively moving said pulldown means in a direction parallel to the axis of reciprocal movement of said mandrel means; f. means for preselecting said increments of stock advancement for a particular diameter barrel; and g. means for preselecting particular mandrel positions corresponding to the particular advancement positions of the stock along said longitudinal path; wherein the diameter of the cylindrical elements is determined by selection of a particular stock advancement interval and of particular mandrel positions in relation to the advancement positions of the stock along said longitudinal path.

Claim 24

A press apparatus as defined in claim 19 wherein said pulldown means comprises a pair of spaced vertically aligned pulldown members, one disposed on each side of said die surface, said pulldown members having said mandrel extending normally therebetween, parallel to the axis of the barrel being formed, thus allowing the formed portion of the stock to circumvent said mandrel to form a complete cylinder.

Claim 25

A press apparatus as defined in claim 20 wherein said pulldown members have aligned passages formed therein for axially receiving said mandrel, and including means for axially retracting said mandrel from one of said passages and from the cylindrical barrel, to allow the barrel to be removed from the apparatus in a direction normal to said axis.

Claim 28

A method as set forth in claim 22 wherein said exit portion of said continuous die surface is convex with respect to the workpiece, thereby allowing a rolling engagement there-between as the mandrel is lowered.

Claim 29

A method as set forth in claim 22 wherein said concave portion of said continuous die surface is of substantially uniform curvature thereby allowing for smooth advancement of the workpiece and preventing stress concentration in said die surface.

Claim 30

A method as set forth in claim 22 wherein said majoR angle between the entrance plane and the mandrel lowering axis is in the range of 60*-80*.

Claim 31

A method as set forth in claim 22 and including a prelininary step of pre-registering the associated predetermined distances of stock advancement and mandrel-lowering for each sequential increment to obtain the desired workpiece profile.

Claim 32

A method as set forth in claim 24 wherein at each sequential increment the workpiece is permanently deformed in accordance with the pre-registered distance and wherein after lowering of the mandrel at each increment the following steps are performed: a. raising the mandrel to a pre-determined desired-bend-point and establishing whether the workpiece portion has been permanently deformed to said bend point; b. lowering the mandrel to a position closer to said die surface than that of the previous lowering for that increment, provided that the workpiece portion has not been permanently deformed to said bend point; and c. repeating the above steps until the workpiece portion has been permanently deformed to said bend point.

Claim 33

A method as set forth in claim 25 wherein the establishing of whether the workpiece portion has been permanently deformed to said bend point is accomplished by: a. allowing the mandrel to be displaced upwardly by reaction to contact pressure from the workpiece; and b. sensing any upward displacement of said mandrel by a pressure sensitive device disposed thereabove.

Claim 34

A method as set forth in claim 22 wherein the process includes the establishing and maintaining of positive continuous control of the workpiece by a feeder means mounted on the entrance plane so as to be movable on that plane in both the longitudinal and transverse directions.

Claim 35

A method as set forth in claim 27 and including the step of transversely aligning the workpiece so that one of the longitudinal edges thereof coincides with the longitudinal path of advancement.

Claim 36

A method as set forth in claim 24 wherein transverse forces are applied to opposite longitudinal edges of the workpiece with the force on one edge being greater than the force on the opposite edge, thereby allowing the workpiece to be transversely positioned with its opposite edge coincident with a desired reference plane.

Claim 37

A method as set forth in claim 22 wherein the workpiece is removed in the following manner: a. retracting the mandrel in a direction normal to both the path of advancement and the mandrel-lowering axis; and b. removing the workpiece in a plane formed by the mandrel lowering axis and the path of advancement.

Claim 40

A method as set forth in claim 33 wherein the predetermined distances of advancement are varied with the longitudinal position of the workpiece, and further wherein they are varied such that the sequential increments proximate the longitudinal beginning and end of the workpiece are shorter than those increments near the intermediate portions thereof.

Claim 41

A method as set forth in claim 33 and including a preliminary step of preregistering the associated predetermined distances of stock advancement and mandrel-lowering for each sequential increment to obtain the desired predetermined diameter for a workpiece having a specific thickness.

Claim 42

A method as set forth in claim 33 wherein at the initial increment position the intermediate portion of the workpiece is supported on said entrance plane and the leading end thereof is supported on said concave portion; and at the final increment position, the intermediate portion is supported at said die exit portion and the trailing end thereof is supported on said concave portion, thereby allowing the workpiece to be deformed proximate its ends.