Forming Helical Or Threaded Product Patents (Class 249/59)
  • Patent number: 4871505
    Abstract: A mold and process for integrally forming a modular helical shaped device such as a screw conveyor. The mold has a center operating axis (26) and includes a first section (20A) which forms a portion of the axial member (33). The first section (20A) also forms one of the helical surfaces (36A) disposed around the center axis (26) which has an amount of rotation no greater than 360 degrees. In a similar manner, a second section (20B) is adapted for reciprocating movement along the center axis (26) between an open and closed position with respect to section (20A). The second section (20B) forms the other one of the helical shaped flight members (41). Thus, the two mold sections define a substantially enclosed cavity having an elongated axial portion and a helical shaped flight portion with a selected cross-section that forms the helical shaped device.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: October 3, 1989
    Assignee: The Laitram Corporation
    Inventor: James M. Lapeyre
  • Patent number: 4856980
    Abstract: An apparatus for making parts having complex geometric shapes by injection molding apparatus. The apparatus avoids the formation of a parting line in the molded object. The apparatus includes an injector plate, an ejector plate and a floating plate. The injector plate has at least one mold cavity for making a part and a passageway to allow molten plastic to enter the mold cavity. The ejector plate has at least one mold cavity corresponding to the mold cavity in the injector plate. The floating plate has at least one projection. The plates are adapted to fit together when the mold is closed so that the floating plate is between the injector and ejector plates and the projection fits centrally between the cavities of the injector and ejector plates. A mechanism moves the injector plate, ejector plate and floating plate with respect to one another.
    Type: Grant
    Filed: September 18, 1987
    Date of Patent: August 15, 1989
    Assignee: Schmid Laboratories, Inc.
    Inventor: Joseph N. Laurita
  • Patent number: 4842462
    Abstract: A screwthreaded insert comprises a series of generally cylindrical body portions provided with inclined ribs or teeth, with the teeth of one portion extending in the opposite direction to those of the next adjacent portion, and the successive toothed portions being separated by grooves. The fastener is made by diecasting, and a pair of flats is formed on opposite sides of a diameter of the body.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: June 27, 1989
    Assignee: P.S.M. Fasteners Limited
    Inventor: James M. G. Tildesley
  • Patent number: 4822270
    Abstract: Apparatus for molding a thermoplastic tubular product such as a bushing having an internally threaded major diameter portion and an integral truncated minor diameter portion. A mold provided with a mold shell which jointly with a two-part mold core defines a mold cavity having a shape complementary to the shape of the molded bushing. The molded bushing has an internal undercut in the form of a thread in the major diameter portion thereof. The mold core is made as a core pin and an externally threaded sleeve of greater diameter than the core pin circumferentially of a portion of the core pin. Provision is made for moving the mold elements relatively to define the mold cavity and to effectively release the core by axial compression of the molded product while exposed on the mold core to cause it to swell radially outwardly and release the externally threaded core which forms the internal thread on the molded bushing.
    Type: Grant
    Filed: June 6, 1987
    Date of Patent: April 18, 1989
    Assignee: F. I. P. Formatura Iniezione Polimeri S.p.A.
    Inventors: Giancarlo Bonissone, Piero Mulas
  • Patent number: 4797295
    Abstract: A method of making stick-supported products, particularly ice creams, having undercut or recessed zones formed thereon, the method utilizing a mold (1) which has at least one internal raised thread (2) and one recessed thread (3) and which enables the product to be drawn out of the mold by merely exerting an axially directed pull upon the product-supporting stick (5) followed by a natural rotational movement of the stick in a direction of said threads.
    Type: Grant
    Filed: June 1, 1987
    Date of Patent: January 10, 1989
    Assignee: Sidam S.R.L.
    Inventors: Grigoli Franco, Trabacchi Franco
  • Patent number: 4787596
    Abstract: A mold for the formation of plastic Luer nuts having a polygonal internal cross-section. The mold includes both movable and fixed cavity sections, so that a non-round threaded core can be unscrewed from within the Luer nut.
    Type: Grant
    Filed: December 11, 1987
    Date of Patent: November 29, 1988
    Assignee: Hewlett-Packard Company
    Inventors: Lawrence V. Folding, Roy A. Rosen
  • Patent number: 4755342
    Abstract: A method for producing in a cylindrical thermoplastic material an internal thread by blow molding the thermoplastic material in a mold in which the surface of the mold defining the outer face of the thread is at a negative angle of at least 5 degrees to the planes perpendicular to the axis of the cylindrical material.
    Type: Grant
    Filed: August 13, 1986
    Date of Patent: July 5, 1988
    Inventor: Paul J. Biermann
  • Patent number: 4737334
    Abstract: A novel plastic mold and method is disclosed for forming a Luer nut which has a polygonal internal cross-section. The mold includes both movable and fixed cavity sections, so that a non-round threaded core can be unscrewed from within the Luer nut.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: April 12, 1988
    Assignee: Hewlett-Packard Company
    Inventors: Lawrence V. Folding, Roy A. Rosen
  • Patent number: 4729250
    Abstract: A lead screw for moving, for example, a printing head or a magnetic head. The screw is molded from plastics by a split mold comprising a plurality of longitudinally extending sections. It has on its outer peripheral surface a helical groove satisfying the following relationship: ##EQU1## where P: pitch of the groove;R: radius of the screw;r: radius of the screw between its longitudinal axis and the bottom of the groove;.theta.: angle of division of the mold sections; andL: a half of the difference in width between the top and bottom of the groove. The bottom of the groove is smaller in width than the top thereof.
    Type: Grant
    Filed: January 23, 1986
    Date of Patent: March 8, 1988
    Assignee: Seikosha Co., Ltd.
    Inventors: Yoshiaki Ikeda, Yoshio Tamura, Hiroshi Noritake
  • Patent number: 4728474
    Abstract: Method and apparatus are disclosed for making multi-turned plastic springs. At least 2 mold sections forming a central opening and a cavity with many turns are placed around a hollow sleeve having sufficient opening to flow molten plastic to individual turns. After the plastic solidifies the sleeve is moved with respect to the mold sections to shear a spring that has formed in the cavity from a plastic core in the sleeve. The mold sections are then opened and the spring is removed.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: March 1, 1988
    Assignee: Plough, Inc.
    Inventor: Glenn L. Beall
  • Patent number: 4693861
    Abstract: A mold and process for integrally forming a modular helical shaped device such as a screw conveyor is disclosed. The mold has a center operating axis (26) and includes a first section (20A) which forms a portion of the axial member (33). The first section (20A) also forms one of the helical surfaces (36A) disposed around the center axis (26) which has an amount of rotation no greater than 360 degrees. In a similar manner, a second section (20B) is adapted for reciprocating movement along the center axis (26) between an open and closed position with respect to section (20A). The second section (20B) forms the other one of the helical shaped flight members (41). Thus, the two mold sections define a substantially enclosed cavity having an elongated axial portion and a helical shaped flight portion with a selected cross-section that forms the helical shaped device.
    Type: Grant
    Filed: April 9, 1984
    Date of Patent: September 15, 1987
    Assignee: The Laitram Corporation
    Inventor: James M. Lapeyre
  • Patent number: 4633932
    Abstract: A method of casting or moulding an article having an internally screw-threaded hole comprises introducing casting or moulding material into a mould cavity around a core pin formed with segments of a screw thread separated by flutes and also around withdrawable flat core members projecting into the mould cavity with their leading ends fitting snugly into the flutes. The segments of screw thread form the male image of segments of the required female thread. When the casting or moulding material has set first the core members are withdrawn from the mould cavity then the core pin is rotated to bring the screw-threaded segments into the positions formerly occupied by the flutes and the pin is withdrawn axially from the mould cavity. Finally the article is removed from the mould cavity.
    Type: Grant
    Filed: August 10, 1984
    Date of Patent: January 6, 1987
    Assignee: Dynacast International Limited
    Inventor: James M. Ferguson
  • Patent number: 4622198
    Abstract: A spring member (40) is integrally molded to a radial flange (36) of a coupling nut (30), the spring member including a detent tooth (42) and having one end thereof being formed into the flange and the other end free to flex radiallyinward and outward to engage successive ratchet teeth (14) around the outer periphery of a plug shell (12) to which the coupling nut is rotatably mounted.
    Type: Grant
    Filed: July 18, 1985
    Date of Patent: November 11, 1986
    Assignee: Allied Corporation
    Inventors: David O. Gallusser, David L. Frear
  • Patent number: 4618121
    Abstract: A mold for forming a plastic cap and removing a cap from such a mold. The mold comprises female and male members which, together, form a mold cavity in which the cap is formed. The female member includes an upper assembly and a plurality of cams. The cams have radial protrusions engaging the male member to form annular recesses in the cap. The cap is removed from the mold by moving the upper assembly of the female member axially and the cams thereof radially away from the cap, and then removing the cap itself from the male member of the mold. Preferably the cap is shrunk onto the male member to develop a space between the cap and the female member of the mold prior to moving the female member away from the cap.
    Type: Grant
    Filed: August 15, 1984
    Date of Patent: October 21, 1986
    Assignee: American Safety Closure Corp.
    Inventor: Vincent N. Conti
  • Patent number: 4610621
    Abstract: This relates to a mold for forming closure caps and like cap-like members having a peripheral body with internal threads. The mold is constructed to have an irregular parting line with the result that a major part of the body of the closure cap may be externally defined by that mold member which is moved to an out-of-the-way position when the mold is opened, leaving the injection molded closure cap body free for radial expansion and thus permissible stripping of the closure cap from the core about which it is molded. This construction eliminates the customary ejector sleeve and permits the base mold member to function as an ejector block for directly stripping the molded closure cap from the core. This construction permits mating tapered surfaces on the base mold member and the core which form a seal and do not have relative sliding contact, thereby eliminating previous undesired wear surfaces.
    Type: Grant
    Filed: November 28, 1984
    Date of Patent: September 9, 1986
    Assignee: Continental White Cap, Inc.
    Inventors: James M. Taber, Stephen J. Kras
  • Patent number: 4578028
    Abstract: A radially expandable core pin is disclosed for blow-molding a thermoplastic container having a body-portion and a neck-portion, with such neck-portion including a dispensing orifice and internal attachment means. The core pin is radially expandable to compression mold the internal attachment means of the container and comprises a plurality of circumferentially disposed core sections surrounding the central axis of the core pin. These core sections are radially movable between a normally collapsed position and an expanded position, and have outer surfaces which mate along their longitudinal adjacent sides when radially displaced to expanded position to form a substantially continuous neck-forming surface thereabout. The neck-forming surface is relieved in a predetermined pattern to form the internal attachment means of the container.
    Type: Grant
    Filed: December 6, 1984
    Date of Patent: March 25, 1986
    Assignee: The Procter & Gamble Company
    Inventors: William P. Dirksing, Marvin G. Leman, Robert H. Van Coney
  • Patent number: 4570897
    Abstract: A container mold comprising a mold cavity portion and a mold core portion with the cavity and core portions being relatively moveable between a closed and an open position. By this invention, means are provided for molding a recess-defining flange in the container.
    Type: Grant
    Filed: January 23, 1985
    Date of Patent: February 18, 1986
    Inventor: John W. Von Holdt
  • Patent number: 4567954
    Abstract: Replaceable nozzles may be provided in a tungsten carbide drill bit manufactured by powder metallurgical infiltration techniques wherein at least one nozzle is threaded into a corresponding molded threaded bore in the bit. Despite the practical nonmachinability and brittleness of the tungsten carbide material, secure threaded insertion can be achieved if a squared thread design is used, and if the mold plug for forming the threaded bore is oversized to take into account the average variation in shrinkage in a bit formed by powder metallurgical infiltration techniques.
    Type: Grant
    Filed: December 2, 1983
    Date of Patent: February 4, 1986
    Assignee: Norton Christensen, Inc.
    Inventors: Robert W. Voight, III, Jerry L. Robin, Lorenzo G. Lovato, Robert J. Balkenbush, Joseph D. McDermaid
  • Patent number: 4554962
    Abstract: A method of casting or moulding an internally screw-threaded article comprises introducing casting or moulding material around two withdrawable flat core members which overlap within a mould cavity. The leading end face of each core member is formed with a male segment of the female screw thread to be formed in the article, the arrangement being that when the core members meet one another the two screw thead segments of the two core members are located to form two diametrally opposite segments of a male image of said female screw thread, withdrawing the core members from the mould cavity when the casting or moulding material has set and removing the cast article from the mould cavity.
    Type: Grant
    Filed: August 10, 1984
    Date of Patent: November 26, 1985
    Assignee: Dynacast International Limited
    Inventor: David E. Wright
  • Patent number: 4552328
    Abstract: A tamper proof closure cap for a container, a tool for manufacturing the cap and a method for removing the cap from the tool are defined. The cap is designed with the tamper proof skirt as a unitary structure with the main body of the cap. The skirt has unique structural aspects which allow for less complexity in the tool and ease of removal of the cap from the tool. The tool includes a stripper ring which laterally support the skirt and permits a shift of the pivot plane for the skirt relative to the main body portion during removal of the cap from the mold.
    Type: Grant
    Filed: March 1, 1985
    Date of Patent: November 12, 1985
    Assignee: Sun Coast Plastics, Inc.
    Inventors: Herbert V. Dutt, Paul A. Santostasi
  • Patent number: 4541605
    Abstract: Present invention relates to a metal mold device comprising a female die, a die frame having a hole and a male die assembly moving along an axis of the hole to produce a plastic molding having an opening with a partially waved inner sidewall. The male die assembly comprises a generally upwardly tapering central base having a rectangular top and four side slopes, a pair of opposed primary slide members and a pair of opposed auxiliary slide members. The primary slide members are strictly mounted on the opposed side slopes respectively while the auxiliary slide members are loosely mounted on the remained opposed side slopes respectively.
    Type: Grant
    Filed: February 14, 1984
    Date of Patent: September 17, 1985
    Assignee: Daiichi-Geyer Kabushiki Kaisha
    Inventors: Kazuho Kubota, Masao Todoroki
  • Patent number: 4541795
    Abstract: A mold and a molding method are described for forming a closure device having a cap portion, a cylindrical plug portion extending therefrom, and a cylindrical collar extending substantially coextensively and coaxially with the plug portion spaced therefrom to provide an annular recess for receiving the open end of the container to be closed. The mold cavity is defined by mold segments and by a substantially cylindrical hollow outer core which extends into the mold cavity and defines the annular recess in the closure device between the collar and the plug portion. The mold segments include a gripping portion for retaining the closure device. The gripping portion retains the closure device while the outer core is extracted from the cavity. The gripping portion of the mold segments is then separated along with the remainder of the mold segments to remove the molded device.
    Type: Grant
    Filed: July 31, 1984
    Date of Patent: September 17, 1985
    Assignee: James R. Goldberg
    Inventor: Harold E. Cole
  • Patent number: 4519569
    Abstract: For the molding of bottle caps having irregular lower boundaries, such as caps having depending tabs, the conventional mold has a core and a surrounding sleeve in which the core slides. This is modified by using a split sleeve which is maintained in close contact with the core during molding, but whose elements are freed to move outwardly away from the core when the mold begins to open. This solves the prior art problem of the galling of the contacting surfaces of sleeve and core.
    Type: Grant
    Filed: April 5, 1984
    Date of Patent: May 28, 1985
    Assignee: Maxcap, Inc.
    Inventor: Robert L. Nolan
  • Patent number: 4456214
    Abstract: A molding core has side by side segments assembled for rocking about pivots intermediate their ends, and are rocked to their alternate positions by an actuating pin (or pins) having camming surfaces for that purpose, arranged for non-interference of the pin with the rocking movements of the segments.
    Type: Grant
    Filed: December 6, 1982
    Date of Patent: June 26, 1984
    Assignee: Roehr Tool Corporation
    Inventors: Wilf Ruck, Brian Russell, George L. Roehr, Paul R. Catalanotti
  • Patent number: 4383819
    Abstract: A bucket shaped container having a rim opening smaller than the diameter of the sidewall thereof is injection molded from thermoplastic material using a die set including a molding core which collapses to allow axial removal of the molded container from the mold. The molding core comprises a plurality of individual, wedge shaped outer core sections which collectively form a continuous molding surface and are slidably mounted on a tapered inner core to allow axial sliding movement of the outer core sections relative to the inner core. Each of the outer core sections is also mounted for radial sliding movement on a mounting plate which circumscribes the molding core and is mounted for reciprocating axial movement relative to the inner core. Reciprocation of the mounting plate produces simultaneous axial and radial movement of the outer core sections throughout their entire lengths between an expanded molding position and a collapsed container releasing position.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: May 17, 1983
    Assignee: Letica Corporation
    Inventor: Ilija Letica
  • Patent number: 4352387
    Abstract: A process for producing a hollow cast product in which a hollow flexible mandrel is placed into the crucible of a mold with one end of the mandrel extending out of the mold, molten metal is introduced into the mold crucible and left to solidify in the crucible and the mandrel is removed from the mold to thereby form a hollow cast product having a bore which has the smooth or concavo-convex peripheral surface and is straight, bent or meandering.
    Type: Grant
    Filed: May 24, 1979
    Date of Patent: October 5, 1982
    Assignee: Sankyo Oilless Industry, Inc.
    Inventor: Shinjiro Yamaguchi
  • Patent number: 4299371
    Abstract: A neck ring assembly including ejector pins for engaging a parison finish for holding a parison centrally within a neck ring upon the initial opening of the assembly in a positive stripping action. After a small amount of neck ring opening, the neck rings are free of the parison finish permitting no further side load on the take-out mechanism. The stripping mechanism including ejector pins is then completely drawn away from the parison to allow the parison to be removed. The device is simple in construction, has few moving parts, and requires no auxiliary power for operation.
    Type: Grant
    Filed: August 25, 1980
    Date of Patent: November 10, 1981
    Assignee: Emhart Industries, Inc.
    Inventor: Robert J. Duga
  • Patent number: 4280976
    Abstract: A simultaneously molded threaded port and plug may be produced by a mold which comprises a first cavity for receiving molding compound to form a wall, a second cavity for receiving molding compound to form the threaded plug, and rotatable shaft means carrying external thread forming grooves and extending through the first cavity to define the threaded port. The shaft means terminates at the second cavity, with an end portion of the shaft being shaped to form a separable mechanical linkage between the end portion and the plug molded in the second cavity means. The shaft is rotated after molding to withdraw it from the molded, threaded port, and to rotate the molded, threaded plug into the threaded port for sealing thereof.
    Type: Grant
    Filed: April 18, 1980
    Date of Patent: July 28, 1981
    Inventor: John W. von Holdt
  • Patent number: 4280549
    Abstract: Apparatus and method for producing a die cast article, such as a gear wheel having helical teeth, in which the die cavity is defined by fixed elements and a rotatable element. On completion of the casting the cast article can be ejected from the casting cavity on relative rotation between the fixed elements and rotatable element so that the cast helical teeth of the article can be removed in an undamaged condition.
    Type: Grant
    Filed: April 6, 1979
    Date of Patent: July 28, 1981
    Assignee: Keystone International, Inc.
    Inventor: Stephen Gibbs
  • Patent number: 4239174
    Abstract: A two-step ejector structure for molds for injection molding and the like has a first ejector member arranged to be directly acted upon for ejection and to act upon an ejector pin carrier which is to be displaced in the first and second ejector steps, and a second ejector member acting upon a second ejector pin carrier which is to be displaced only in the first ejector step, and a coupling to accomplish the movement of the second ejector member during a predetermined first portion of the ejector movement of the first ejector member and thereafter release the first ejector member from the second ejector member and lock the second ejector member to a member securedly connected to a tool.
    Type: Grant
    Filed: November 14, 1979
    Date of Patent: December 16, 1980
    Inventors: Hans Muller, Nils G. Nilsson
  • Patent number: 4238106
    Abstract: The invention provides an improved cooling arrangement for the core pin of a commercially available injection molding machine permitting a significant reduction in the cycle time of such machine. The core pin is fabricated by the assembly of a plurality of concentric sleeve-like members, one of which is provided with six parallel helically disposed external grooves which respectively define three parallel passages for cooling fluid inlet and three parallel outlet passages for the heated fluid. The arrangement provides a significant increase in the quantity of cooling fluid flowing through the core pin, hence permits a significant decrease in cycle time of the injection molding machine.
    Type: Grant
    Filed: December 3, 1979
    Date of Patent: December 9, 1980
    Assignee: Owens-Illinois, Inc.
    Inventor: Wendell D. Willingham
  • Patent number: 4139176
    Abstract: A mold, for screw-threaded articles, has screw-thread forming spindles rotatable by obliquely toothed gearing so as to apply axial thrust to the spindles and thus compensate for friction and adhesion in unloading of the mold.
    Type: Grant
    Filed: July 27, 1977
    Date of Patent: February 13, 1979
    Inventor: Johannes G. Wundsch
  • Patent number: 4130264
    Abstract: An expandable core for forming an internal recess in a molded part, composed of a stationary core pin having a generally conical outer surface and a segmented sleeve composed of two groups of lateral slides disposed around the pin with the slides of one group alternating with the slides of the other group. The conicity of the pin outer surface and the slide guidance along the pin are identical for all slides of the same group but are different from one group to the other.
    Type: Grant
    Filed: October 26, 1977
    Date of Patent: December 19, 1978
    Assignee: Geyer & Co.
    Inventor: Peter Schroer
  • Patent number: 4119394
    Abstract: Apparatus for forming an end finish on a hollow article having a plastically deformable tubular end portion terminating in an open end of the article. A mold surface surrounds the end portion in juxtaposition with its outer surface, and an expandable tubular membrane is received within the end portion in juxtaposition with the inner surface thereof. The interior of the membrane is sealed from the ambient, elongation of the membrane is restricted, and expansion of the membrane is limited to a lateral zone thereof coextensive with the end portion. The outer surface of the end portion is conformed to the mold surface by subjecting the interior of the membrane to a fluid under pressure to expand the membrane laterally in engagement with the inner surface of the end portion.
    Type: Grant
    Filed: March 28, 1977
    Date of Patent: October 10, 1978
    Assignee: The Continental Group, Inc.
    Inventor: John T. Cary
  • Patent number: 4115505
    Abstract: A die cavity is delineated by the surfaces of a pair of die members and the threaded surface of a first of a pair of thread engageable members, one of the die members thread engaging a part of the threaded surface. A synthetic polymeric resin is injection molded in the cavity to produce a second member in precise thread engagement with the first member and the cavity is then opened to release the thread engaged members.
    Type: Grant
    Filed: February 25, 1977
    Date of Patent: September 19, 1978
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventor: Tsuneyo Metabi
  • Patent number: 4099903
    Abstract: A bottle cap is constructed with stepped portions, including a large diameter serrated lower portion, an intermediate diameter threaded portion, and a smaller diameter serrated upper portion. The cap is produced by deep drawing on a mold core having a base portion carrying a pedestal, to which a thread-forming portion is rigidly secured. A large diameter, lower serration-forming portion and a small diameter, upper serration-forming portion are rotatably mounted on the pedestal below and above the thread-forming mold portion, respectively. After the bottle cap is formed the pedestal is rotated, to disengage the completed cap from the mold core.
    Type: Grant
    Filed: April 12, 1977
    Date of Patent: July 11, 1978
    Inventor: Zafir Petrov
  • Patent number: 4084780
    Abstract: A plug assembly, for temporary use with a concrete product insert having a coil defining an interior threaded surface, holds the insert in position adjacent a mold wall and prevents the interior of the coil from being filled with concrete. The plug assembly includes a plug having a hollow cylindrical elastomeric body defining a cavity which is open at one end of the body and a stem in the cavity attached to the body internally and extending out of the cavity a distance sufficient to provide for use of the stem as a handle. The outer surface of the cylindrical, elastomeric body is proportioned and threaded for firm matching engagement with the threaded coil interior surface upon predetermined radial compression and axial expansion of the body from its substantially unstressed condition. A support means has a first portion for insertion into the cavity in the elastomeric body and a second portion for attachment to a mold wall.
    Type: Grant
    Filed: January 21, 1977
    Date of Patent: April 18, 1978
    Assignee: The Dayton Sure-Grip & Shore Company
    Inventor: Richard C. Mess
  • Patent number: 4079475
    Abstract: A process for casting or molding a single internal thread at the same time that the desired product is cast or molded. The desired thread configuration is defined by two aligned and abutting identical core pins. Each of the pins has a protruding portion in the shape of a helical ramp extending through an angle of less than 360.degree.. The ramp has an outer diameter and pitch corresponding to the diameter and pitch of the desired internally threaded surface to be formed. The protruding portion of each core pin includes a vertically oriented surface extending between the ends of the ramp. A peripheral edge groove extending along the outer edge of the ramp defines the desired thread configuration. The aligned core pins are placed within a recess formed by mating portions of a die block to define the shape of the desired product.
    Type: Grant
    Filed: March 9, 1977
    Date of Patent: March 21, 1978
    Assignee: Coats & Clark, Inc.
    Inventor: Keith Thompson
  • Patent number: 4059249
    Abstract: A core for the injection molding of plastic articles having internal threads, provides a means for readily releasing the article from the mold. The core has a non-rotating, water-cooled center section to hold the molded article against rotary motion and a driven, water-cooled ring section for molding threads in the article. Rotation of the ring section coupled with the holding action of the stationary center section releases the molded thread and ejects the article from the core by the axial force of the thread of the core bearing against the molded thread of the article.
    Type: Grant
    Filed: December 30, 1976
    Date of Patent: November 22, 1977
    Assignee: United States Steel Corporation
    Inventor: Herbert W. Galer
  • Patent number: 4019711
    Abstract: A core is provided, useful in the manufacture of closure caps, each closure cap having a top, dependent skirt and securing means, comprising intermittent or interrupted threads or hold-down lugs.
    Type: Grant
    Filed: November 10, 1975
    Date of Patent: April 26, 1977
    Assignees: J & J Tool and Mold Ltd., Consumers Glass Co., Ltd.
    Inventors: Jack Altenhof, John Altenhof, Robert Chartier
  • Patent number: 3971841
    Abstract: Molding devices and methods for producing a low cost, multi-element, adjustable focus lens assembly for use in photographic apparatus. The assembly features a two-part molded plastic lens mount comprising forward and rear mounts, each having an uncentered lens element insert molded and centered therein and an integrally molded screw thread for coupling the forward and rear mounts together. The molding devices comprise cavity molds having movably mounted zonal clamps therein for centering the lens element within the cavity and for disengaging the molded mounts from surfaces in the molds that form the screw threads.
    Type: Grant
    Filed: June 20, 1974
    Date of Patent: July 27, 1976
    Assignee: Polaroid Corporation
    Inventor: Leon Rubinstein
  • Patent number: 3940103
    Abstract: This invention relates to a plastic closure or cap-type stopper of which the outer skirt has formed on its inner surface a plurality of ribs adapted to engage the top ring and the grooves of the neck of the container to be stopped, on either side of a partially tearable guaranty strip bounded by circular thinning grooves formed in the inner surface of the skirt.The mold for manufacturing this closure comprises underneath a fixed plate formed with holes for the passage of the ejection ring and ejection shaped sleeve of a sliding plate perforated like the fixed plate and actuated by a pusher, and above a sliding impression plate of which the perforation corresponding to the preceding ones bounds the injection chamber for the closure skirt on the core, said sliding impression plate being actuated by a pusher for releasing the closure from the mold impression at the end of its stroke.
    Type: Grant
    Filed: February 7, 1975
    Date of Patent: February 24, 1976
    Assignee: Captocap Limited
    Inventor: Fernand Hilaire
  • Patent number: 3930770
    Abstract: An expandable poincon assembly to be used for forming a headpiece onto a preformed thin-walled plastic or laminate tube or bag provides a poincon upon which the loose fitting preformed thin-walled tube can be loaded. After tube loading, the poincon is inserted into a female forming member. Toward the end of the poincon's insertion stroke, a soupape which is mounted for axially movement within the head end of the poincon contacts the female forming member and then partially retracts into the head end of the poincon as the poincon continues to advance to the end of its insertion stroke. A conically-shaped washer mounted on the bottom end of the soupape is peripherally expanded by the continued advancement of the poincon after the top end of the soupape has contacted the female forming member.
    Type: Grant
    Filed: February 24, 1975
    Date of Patent: January 6, 1976
    Assignee: American Can Company
    Inventors: David Alvin Gaudet, John Moss Wathen, Jr.