EP0171507A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Thermoforming equipment for differential pressure forming products in thermoplastic material
Assignee: Kvaerner US Inc
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Filing: 1985-04-03
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Granted: —
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Expires: 2005-04-03
Abstract
Abstract Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material wherein a mold station incorporates female mold mechanism and opposed mold mechanism, a web advancing mechanism indexes a plastic web in which products are to be formed between said mold mechanisms, a drive moves the female and opposed mold mechanisms between open and closed positions on opposite sides of the plastic web, severing knife means is cooperable with a final increment of said relative movement to dispose said mechanism in closed position to sever the products formed from the web, and ejector mechanism is operable after severing is accomplished and there has been relative movement of said mold mechanisms toward open position to eject the product. Improvements claimed include pusher means operated by the relative movement to push the ejected product in a direction to clear the mold station, a dancer arm assembly movable in an oscillating path angularly to the longitudinal extent of said advancing mechanism and web to pull a section of web from the roll such as to form a loop of predetermined extent and then release it for movement in indexed increments to the mold station, the assembly being driven by a drive crank pivotally connected to a dancer arm assembly link for moving said link through part of a revolution wherein it drives said dancer arm assembly first at a gradually accelerating speed, then at increased speed, and finally at a gradually decelerating speed, expandable and contractible toggle links for driving at least one mold mechanism, and "no trim" mechanism operative to disable final incremental relative movement of the mold mechanism which otherwise severs the product formed from the web.
Inventors
- 👤 Robert C. Whiteside
- 👤 Albert W. Arends
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 07:16
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/26; B29C51/30; B29C51/32; B29C51/18; B29C51/44
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
310 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web, in which products are to be formed, between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between mold open and mold closed positions on opposite sides of said plastic web; e. a roll stand upstream from said mold station for supporting a roll of the plastic web in a position aligned longitudinally with said mold station such that a supply of the web can be unwound from the roll and fed to the web advancing mechanism; f. heater elements disposed between the roll stand and mold station for heating the web to a moldable state; g. a dancer arm assembly movable in an oscillating path angularly to the longitudinal extent of said advancing mechanism and web to pull a section of web from the roll such as to form a loop of predetermined extent and then release it for movement in indexed increments to the mold station; h. means mounting said dancer arm assembly for swinging movement about a generally horizontal axis extending transversely to the web; i. a link connected to the dancer arm assembly for moving it in an oscillating path; and j. a drive crank pivotally connected to said link for moving said link through part of a revolution wherein it drives said dancer arm assembly first at a gradually accelerating speed, then at increased speed, and finally at a gradually decelerating speed, when it is moved both in a direction to release the web to the advancing mechanism and then away from the web to pull a further increment of web from the roll.
Claim 2
Dependent Claim
310 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web, in which products are to be formed, between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between mold open and mold closed positions on opposite sides of said plastic web; e. a roll stand upstream from said mold station for supporting a roll of the plastic web in a position aligned longitudinally with said mold station such that a supply of the web can be unwound from the roll and fed to the web advancing mechanism; f. heater elements disposed between the roll stand and mold station for heating the web to a moldable state; g. a dancer arm assembly movable in an oscillating path angularly to the longitudinal extent of said advancing mechanism and web to pull a section of web from the roll such as to form a loop of predetermined extent and then release it for movement in indexed increments to the mold station; h. means mounting said dancer arm assembly for swinging movement about a generally horizontal axis extending transversely to the web; i. a link connected to the dancer arm assembly for moving it in an oscillating path; and j. a drive crank pivotally connected to said link for moving said link through part of a revolution wherein it drives said dancer arm assembly first at a gradually accelerating speed, then at increased speed, and finally at a gradually decelerating speed, when it is moved both in a direction to release the web to the advancing mechanism and then away from the web to pull a further increment of web from the roll.
Claim 3
Dependent Claim
45 words
The invention of claim 1 wherein said crank comprises an arm connected at one end to said link and mechanism connected with the opposite end of said arm for driving it through part of an arc of revolution about said opposite end of the arm.
Claim 4
Dependent Claim
65 words
The invention of claim 2 wherein said mechanism for driving the arm in rotation comprises a spur gear, at least one rack engaged with said spur gear in mesh therewith, and separate power cylinders powering said rack in correlation with said web advancing mechanism to revolve said gear first in one direction of rotation when the advancing mechanism is operating, and then the return direction.
Claim 5
Dependent Claim
226 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web, in which products are to be formed, between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between open and closed positions on opposite sides of said plastic web; e. said means for relatively moving said mold mechanisms including toggle links connected between said frame and one of said mold mechanisms, and drive means for relatively expanding and contracting said toggle links to move said one mold mechanism toward the other mold mechanism to a forming position; f. severing knife means around said cavity forming means cooperable with a final increment of relative movement of said mold mechanisms beyond forming position to dispose said mold mechanisms in a most closed final position of closure to sever the products formed from the web; g. said means for relatively moving said mold mechanisms including means normally operable to dispose said mold mechanisms in said final severing position; and h. "no trim" mechanism operative to disable said latter normally operable means when it is not desired to sever the products formed from the web with said severing means.
Claim 6
Dependent Claim
226 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web, in which products are to be formed, between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between open and closed positions on opposite sides of said plastic web; e. said means for relatively moving said mold mechanisms including toggle links connected between said frame and one of said mold mechanisms, and drive means for relatively expanding and contracting said toggle links to move said one mold mechanism toward the other mold mechanism to a forming position; f. severing knife means around said cavity forming means cooperable with a final increment of relative movement of said mold mechanisms beyond forming position to dispose said mold mechanisms in a most closed final position of closure to sever the products formed from the web; g. said means for relatively moving said mold mechanisms including means normally operable to dispose said mold mechanisms in said final severing position; and h. "no trim" mechanism operative to disable said latter normally operable means when it is not desired to sever the products formed from the web with said severing means.
Claim 7
Dependent Claim
90 words
The invention of claim 4 wherein said toggle links are interconnected by an eccentric pin and socket mechanism, said drive means includes a crank arm, and said means normally operable to dispose said mold mechanisms in final severing position includes a connecting rod connecting the crank arm with said eccentric pin and socket mechanism such that movement of said crank arm in a direction to contract said toggle links first causes pivoting of said eccentric pin and socket mechanism in one direction to create said final increment of closing movement.
Claim 8
Dependent Claim
45 words
The invention of claim 5 wherein said "no trim" mechanism includes a power cylinder connected between said eccentric pin and socket mechanism and connecting rod to alter the effective stroke producing positions thereof by pivoting said eccentric pin and socket mechanism in the opposite direction.
Claim 9
Dependent Claim
24 words
The invention of claim 4 wherein said one mold mechanism is stationary and movement of the other mechanism produces all of the relative movement.
Claim 10
Dependent Claim
30 words
The invention of claim 7 wherein it is the mold mechanism with the cavity forming means which moves and the other mold mechanism mounts reciprocable cylinder operated plug assist members.
Claim 11
Dependent Claim
209 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web in which products are to be formed between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between open and closed positions on opposide sides of said plastic web; e. severing knife means around said cavity forming means cooperable with a final increment of said relative movement to dispose said mechanism in closed position to sever the products formed from the web; f. said means for relatively moving said mold mechanisms including drive gear for causing relative movement to dispose the mold mechanisms in forming position, and then a final most-closed position in which severing of the articles by said severing knife means is accomplished; g. ejector pin mechanism operable after severing is accomplished and there has been relative movement of said mold mechanisms toward open position to eject the product from the cavity forming means; and h. pusher means operated by said relative movement to push the ejected product in a direction to clear the mold station.
Claim 12
Dependent Claim
209 words
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material comprising: a. a frame; b. a mold station incorporated therewith and including female mold mechanism with cavity forming means and opposed mold mechanism; c. longitudinally extending, web advancing mechanism for indexing a plastic web in which products are to be formed between said mold mechanisms; d. means for relatively moving said female and opposed mold mechanisms between open and closed positions on opposide sides of said plastic web; e. severing knife means around said cavity forming means cooperable with a final increment of said relative movement to dispose said mechanism in closed position to sever the products formed from the web; f. said means for relatively moving said mold mechanisms including drive gear for causing relative movement to dispose the mold mechanisms in forming position, and then a final most-closed position in which severing of the articles by said severing knife means is accomplished; g. ejector pin mechanism operable after severing is accomplished and there has been relative movement of said mold mechanisms toward open position to eject the product from the cavity forming means; and h. pusher means operated by said relative movement to push the ejected product in a direction to clear the mold station.
Claim 13
Dependent Claim
94 words
The invention of claim 9 wherein said pusher is mounted for longitudinal back and forth movement and is linked to one of said mold mechanisms, the mold mechanism to which it is linked being driven by said drive gear means for relatively moving the mold mechanisms; the pusher being linked in a manner to move from a position upstream of said mold station to a position between said mold mechanisms after some relative movement of the mold mechanisms toward open position, and to return with relative movement of the mold mechanisms toward closed position.
Claim 14
Dependent Claim
41 words
The invention of claim 10 wherein linkage for linking the pusher to the said one mold mechanism is provided which delays moving the pusher between the mold mechanisms until the ejector pin means moves the product above the cavity forming means.
References Cited (Backward Citations)
No citation records indexed.
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