Hollow article internal pressure forming apparatus and method

Claim 2

In a forming apparatus for bulging hollow bulbous metal knobshells outwardly relatively small distances against enclosing die cavity surfaces by application of only internal high fluid pressures directed solely through a preformed reduced size knobshell neck access opening; the apparatus including: first and second dies constructed and arranged with said dies movable longitudinally together to a closed position and thereafter in said closed position by continued longitudinal urging placing said dies in progressive longitudinal pressure exerting conditions, said dies in said closed position forming a die cavity having surfaces enclosing said knobshell with a reduced size knobshell neck access opening exposed to said first die, said die cavity surfaces outwardly of said knobshell being exposed at all times venting to the atmosphere; die moving means for moving said dies to and from said closed position and progressively urging said dies into said die longitudinal pressure exerting conditions only while in said closed position; fluid pressure means operably connected free of reaction until said dies are in closed position but directly fluid flow reactive to said dies being urged into said die progressive longitudinal pressure exerting conditions and operably connected to said first die directing fluid flow into said knobshell through said knobshell neck access opening, said fluid pressure means during said dies being urged into said progressive longitudinal pressure exerting conditions at all times exerting a greater reverse longitudinal force on said dies tending to retain said dies in closed position than knobshell forming force created internally outwardly from within said knobshell against said die cavity surfaces tending to urge said dies apart.

Claim 3

In a forming apparatus as defined in claim 1 in which said fluid pressure means includes a fluid cylinder operably connected to one of said dies and having a piston longitudinally movable by said one die progressively forcing fluid into said knobshell through said knobshell neck access opening as said one die is placed in said progressive longitudinal pressure exerting conditions.

Claim 4

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means.

Claim 5

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; and in which said fluid pressure means includes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions.

Claim 6

In a forming apparatus as defined in claim 1 in which said fluid pressure means includes automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions.

Claim 7

In a forming apparatus as defined in claim 1 in which said fluid pressure means includes automatic fluid refill means for automatically refilling said fluid pressure means with fluid to a maximum predetermined amount between said dies being urged into said progressive longitudinal pressure exerting conditions.

Claim 8

In a forming apparatus as defined in claim 1 in which one of said dies includes knockout means operably connected thereto reciprocal between a retracted normal position and an extended knockout position for removing said knobshell from said one die during movement into said extended knockout position, said knockout means remaining in said retracted normal position during said movement of said dies into said closed position and urging of said dies into said longitudinal pressure exerting conditions and being movable into said extended knockout position during movement of said one die away from said closed position, said knockout means having a part of said fluid pressure means formed therethrough for establishing fluid flow of said fluid pressure means, into said knobshell neck access opening when said knockout means is in said retracted normal position and interrupting said fluid flow of said fluid pressure means when said knockout means is moved to said extended knockout position.

Claim 9

In a forming apparatus as defined in claim 1 in which said first die includes knockout means operably connected reciprocal within said first die between a retracted normal position and an extended knockout position for removing said knobshell from said first die during movement into said extended knockout position, said knockout means remaining in said retracted normal position during said movement of said dies into said closed position and urging of said dies into said longitudinal pressure exerting conditions and being movable into said extended knockout position during movement of said first die away from said closed position, said knockout means having a part of said fluid pressure means formed therethrough within said first die for establishing fluid flow of said fluid pressure means into said knobshell neck access opening when said knockout means is in said retracted normal position and interrupting said fluid flow of said fluid pressure means into said knobshell neck access opening when said knockout means is moved to said extended knockout position.

Claim 10

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; in which said fluid pressure means incudes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions; and in which said fluid pressure means includes automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions.

Claim 11

In a forming apparatus as defined in claim 1 in which said fluid pressure means includes automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions, automatic fluid refill means for automatically refilling said fluid pressure means with fluid to a maximum predetermined amount between said dies being urged into said progressive longitudinal pressure exerting conditions.

Claim 12

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a stationary position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; and in which said fluid pressure means includes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions, automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions, automatic fluid refill means for automatically refilling said fluid pressure means with fluid to a maximum predetermined amount between said dies being urged into said progressive longitudinal pressure exerting conditions.

Claim 13

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; in which said fluid pressure means includes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions; and in which one of said dies includes knockout means operably connected thereto reciprocal between a retracted normal position and an extended knockout position for removing said knobshell from said one die during movement into said extended knockout position, said knockout means remaining in said retracted normal position during said movement of said dies into said closed position and urging of said dies into said longitudinal pressure exerting conditions and being movable into said extended knockout position during movement of said one die away from said closed position, said knockout means having a part of said fluid pressure means formed therethrough for establishing fluid flow of said fluid pressure means into said knobshell neck access opening when said knockout means is in said retracted normal position and interrupting said fluid flow of said fluid pressure means when said knockout means is moved to said extended knockout position.

Claim 14

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; in which said fluid pressure means includes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions, automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions; and in which one of said dies includes knockout means operably connected thereto reciprocal between a retracted normal position and an extended knockout position for removing said knobshell from said one die during movement into said extended knockout position, said knockout means remaining in said retracted normal position during said movemennt of said dies into said closed position, and urging of said dies into said longitudinal pressure exerting conditions and being movable into said extended knockout position during movement of said one die away from said closed position, said knockout means having a part of said fluid pressure means formed therethrough for establishing fluid flow of said fluid pressure means into said knobshell neck access opening when said knockout means is in said retracted normal position and interrupting said fluid flow of said fluid pressure means when said knockout means is moved to said extended knockout position.

Claim 15

In a forming apparatus as defined in claim 1 in which one of said dies is longitudinally reciprocally mounted in a die block normally resiliently urged to a die closed position and thereafter longitudinally urged into said pressure exerting conditions by the other of said dies to progressively actuate said fluid pressure means; in which said fluid pressure means includes a fluid cylinder having a longitudinally movable piston operably connected movable with said one die progressively forcing fluid into said knobshell through said knobshell neck access opening during urging of said one die into said progressive longitudinal pressure exerting conditions, automatic pressure release means automatically limiting maximum pressure exerted by said fluid pressure means internally of said knobshell during said dies being urged into said progressive longitudinal pressure exerting conditions; and in which said first die includes knockout means operably connected in said first die reciprocal between a retracted normal position and an extended knockout position for removing said knobshell from said first die during movement into said extended knockout position, said knockout means remaining in said retracted normal position within said first die during said movement of said dies into said closed position and urging of said dies into said longitudinal pressure exerting conditions and being movable into said extended knockout position during movement of said first die away from said closed position, said knockout means having a part of said fluid pressure means to said knobshell neck access opening formed therethrough for establishing fluid flow of said fluid pressure means into said knobshell neck access opening when said knockout means is in said retracted normal position and interrupting said flow of said fluid pressure means into said knobshell neck access opening when said knockout means is moved to said extended knockout position.

Claim 16

In a method of bulging hollow bulbous metal knobshells outwardly relatively small distances against enclosing die cavity surfaces by application of only internal high fluid pressures directed solely through a preformed reduced size knobshell neck access opening; the steps of: applying a die moving force longitudinally against a first die to move and maintain said first die and a second die together in closed position enclosing a hollow bulbous metal knobshell within a die cavity surrounded by die cavity surfaces; maintaining said die cavity surfaces outwardly of said knobshell at all times venting to the atmosphere; continuing to urge said first die longitudinally while in said closed position by said die moving force; opposing said die moving force urging in said die closed position which opposition will tend to maintain said dies in said closed position by a reactive force resulting from and causing fluid to be forced to flow by said die moving force continued die urging internally of said knobshell through a preformed reduced size knobshell neck access opening creating a forming force tending to separate said dies while fluid pressure forming said knobshell outwardly against said die cavity surfaces; maintaining at all times said reactive force tending to maintain said dies in said closed position greater than said knobshell internal forming force tending to separate said dies.

Claim 17

In a method of bulging hollow bulbous metal knobshells outwardly relatively small distances against enclosing die cavity surfaces by application of only internal high fluid pressures directed solely through a preformed reduced size knobshell neck access opening; the steps of: applying a die moving force longitudinally against a first die to move and maintain said first die and a second die together in closed position enclosing a hollow bulbous metal knobshell within a die cavity surrounded by die cavity surfaces; maintaining said die cavity surfaces outwardly of said knobshell at all times venting to the atmosphere; continuing to urge said first die longitudinally while in said closed position by said die moving force; opposing said die moving force urging in said die closed position which opposition will tend to maintain said dies in said closed position by a reactive force resulting from and causing fluid to be forced to flow by said die moving force continued die urging internally of said knobshell through a preformed reduced size knobshell neck access opening creating a forming force tending to separate said dies while fluid pressure forming said knobshell outwardly against said die cavity surfaces; maintaining at all times said reactive force tending to maintain said dies in said closed position greater than said knobshell internal forming force tending to separate said dies.

Claim 18

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging includes urging said dies in said closed position againt a piston in a cylinder containing said fluid to thereby force said fluid to flow internally of said knobshell through said knobshell neck access opening.

Claim 19

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said method includes the further step of during said step of opposing said die moving force urging, maintaining maximum pressure of said fluid a maximum amount by automatically relieving said pressure above said maximum.

Claim 20

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said method includes the further step of automatically replenishing supply of said fluid to a predetermined amount after said step of opposing said die moving force urging.

Claim 21

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging automatically relieving pressure against said fluid above a predetermined amount during said fluid flow; and in which said method includes the further step of automatically replenishing said fluid to a predetermined amount after said step of opposing said die moving force urging.

Claim 22

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said method includes the further steps of after said forming of said knobshell outwardly against said die cavity surfaces, separating said dies, ejecting said knobshell from said dies, and during knobshell ejection, positively interrupting fluid flow internally of said knobshell.

Claim 23

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging includes urging said dies against a piston within a cylinder to force flow of fluid within said cylinder internally of said knobshell through said knobshell neck access opening, and during said forcing of said fluid flow, automatically relieving pressure against said fluid by said piston above a predetermined maximum amount to limit said fluid pressure to said maximum amount.

Claim 24

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging includes moving said dies against a piston within a cylinder to force flow of fluid within said cylinder internally of said knobshell through said knobshell neck access opening, and during said forcing of said fluid flow, automatically relieving pressure against said fluid by said piston above a predetermined maximum amount to limit said fluid pressure to said maximum amount; and in which said method includes the further step of automatically replenishing supply of said fluid to a predetermined total amount after said step of opposing said die moving force urging has been completed.

Claim 25

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging includes moving said dies against a piston within a cylinder to force flow of fluid within said cylinder internally of said knobshell through said knobshell neck access opening; and in which said method includes the further steps of after said forming of said knobshell outwardly against said die cavity surfaces, separating said dies, ejecting said knobshell from said dies, and during knobshell ejection, positively interrupting fluid flow internally of said knobshell.

Claim 26

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said step of opposing said die moving force urging includes moving said dies against a piston within a cylinder to force flow of fluid within said cylinder internally of said knobshell through said knobshell neck access opening, and during said forcing of said fluid flow, automatically relieving pressure against said fluid by said piston above a predetermined maximum amount to limit said fluid pressure to said maximum amount; and in which said method includes the further steps of after said forming of said knobshell outwardly against said die cavity surfaces, separating said dies, ejecting said knobshell from said dies, and during knobshell ejection, positively interrupting fluid flow internally of said knobshell.

Claim 27

In a method of bulging hollow bulbous metal knobshells as defined in claim 15 in which said method includes the further step of during said step of opposing said die moving force urging, maintaining maximum pressure of said fluid a maximum amount by automatically relieving said pressure above said maximum; and in which said method includes the further steps of after said forming of said knobshell outwardly against said die cavity surfaces, separating said dies, ejecting said knobshell from said dies, and during knobshell ejection, positively interrupting fluid flow internally of said knobshell.