US2308825A - Process for the manufacture of wall plugs - Google Patents

Process for the manufacture of wall plugs Download PDF

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Publication number
US2308825A
US2308825A US349524A US34952440A US2308825A US 2308825 A US2308825 A US 2308825A US 349524 A US349524 A US 349524A US 34952440 A US34952440 A US 34952440A US 2308825 A US2308825 A US 2308825A
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US
United States
Prior art keywords
strands
chamber
tube
fibrous
plug
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US349524A
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English (en)
Inventor
Rawlings John Joseph
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rawlplug Co Ltd
Original Assignee
Rawlplug Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rawlplug Co Ltd filed Critical Rawlplug Co Ltd
Application granted granted Critical
Publication of US2308825A publication Critical patent/US2308825A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
    • F16B13/00—Dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose
    • F16B13/14—Non-metallic plugs or sleeves; Use of liquid, loose solid or kneadable material therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
    • B29C70/083—Combinations of continuous fibres or fibrous profiled structures oriented in one direction and reinforcements forming a two dimensional structure, e.g. mats
    • B29C70/085—Combinations of continuous fibres or fibrous profiled structures oriented in one direction and reinforcements forming a two dimensional structure, e.g. mats the structure being deformed in a three dimensional configuration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/40—Shaping or impregnating by compression not applied
    • B29C70/50—Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
    • B29C70/52—Pultrusion, i.e. forming and compressing by continuously pulling through a die
    • B29C70/523—Pultrusion, i.e. forming and compressing by continuously pulling through a die and impregnating the reinforcement in the die
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/40—Shaping or impregnating by compression not applied
    • B29C70/50—Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
    • B29C70/52—Pultrusion, i.e. forming and compressing by continuously pulling through a die
    • B29C70/525—Component parts, details or accessories; Auxiliary operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/68—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts by incorporating or moulding on preformed parts, e.g. inserts or layers, e.g. foam blocks
    • B29C70/86—Incorporated in coherent impregnated reinforcing layers, e.g. by winding
    • B29C70/865—Incorporated in coherent impregnated reinforcing layers, e.g. by winding completely encapsulated
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04C—BRAIDING OR MANUFACTURE OF LACE, INCLUDING BOBBIN-NET OR CARBONISED LACE; BRAIDING MACHINES; BRAID; LACE
    • D04C1/00—Braid or lace, e.g. pillow-lace; Processes for the manufacture thereof
    • D04C1/06—Braid or lace serving particular purposes

Definitions

  • This invention relates to improvements in wall plugs of the kind intended to be inserted in prepared holes in walls or the like in order to provide a secure fastening for screws, nails and like fastening devices, and further relates to improvements in the manufacture of such plugs.
  • Wall plugs are already known comprising strands of fibrous material arranged longitudinally to form a tube, and held in the tubular form by means of an adhesive.
  • Tubular wall plugs are also already known wherein thin metal wires are combined with fibrous strands, and are woven or plaited into a tubular form, e. g., around a mandrel; such woven or plaited fibrous plugs, with or without the inclusion therein of wires, have been impregnated with various media, such as glue or other suitable adhesive, sodium silicate, or artificial resin.
  • the impregnation of the plug has always been obtained either by passing the separate strands of fibre through a bath of the impregnating medium before formation into a plug or by passing the already formed plug through a bath of impregnating medium.
  • a tubular wall plug having an inner layer formed either of strands arranged longitudinally side by side, or by a strip of thin metal bent longitudinally to form a tube, and having an outer layer formed of strands which are woven or plaited together, the two tubular layers of strands being held together by means of an adhesive or the like with which all the strands in both layers of the plug are impregnated.
  • Each tubular layer may comprise only strands of fibrous material, but preferably the outer layer comprises thin metal wires combined with some or all of the woven or plaited fibrous strands. If desired wires may also be incorporated with the inner layer when such layer comprises longitudinally arranged fibrous strands.
  • the wires may be incorporated with the outer layer of woven or plaited fibrous strands by being woven or plaited therewith or by being twisted around the separate fibrous strands before weaving or plaiting or may be present in such separate fibrous strands before weaving or plaiting in the form of cores.
  • wires may be provided in combination with longitudinal fibrous strands to form the inner layer of the plug, they may either be twisted around some or all of the separate strands or may form cores to some or all of such strands.
  • the woven or plaited strands. comprising the outer layer of the plug are led in a braiding machine from the usual separate spools or bobbins to the point where they are plaited one over the other, the inner layer of the plug being fed inwardly of the separate strands so that the braiding or plaiting takes place actually around the inner tubular layer.
  • the braiding or plaiting is completed within a closed chamber to which the impregnating medium is fed under a constant pressure.
  • the impregnating medium is forced into contact with the strands of fibre comprised in the outer layer of the plug at a time when such strands are still separate, i. e., just before they are braided or plaited together, with the result that a complete impregnation into the component fibres of each separate strand of fibre takes place. Since the. impregnating media commonly employed in the manufacture of wall. plugs are ordinarily of a relatively thick and viscous nature, it is obvious that complete impregnation through the fibres form-ing each of the strands cannot be obtained by passing an already plaited tubular structure through a bath of impregnating medium even if the medium is under pressure in such bath.
  • the new process of manufacture accord.- ing to this invention thus provides a considerable advance in respect of the step of impregnation.
  • the other prior known method of impregnation i. e., that of impregnating the separate strands before they reach the braiding or plaiting point, obviously results in the loss of impregnating medium, accumulation of partially dried and hardened impregnating medium at the point of braiding (which causes frequent stoppages of the machine for removal thereof) and difiiculty in drawing the impregnated strands through the or without the incorporation of metal wires, the
  • said inner layer may be formed in the known manner upon a mandreklwhich extends inwardly through the braiding machine, the outer layer of strands being braided or plaited around the inner layer while the latter is upon the mandrel,
  • the inner layer of the improved plug is formed of a strip ofsheet metal of suitable thickness bent to form a tube or cylinder, the said tube or cylinder serves. adequately to maintain to form a tubular structure 5, shown partly in section in Figure 1.
  • the inner layer may be formed by leading a strip of sheet metal inwardly towards the chamber in which the outer fibrous strands are braided in an impregnating medium, the said strip passing into this chamber through a collar or die through which it is pulled by any convenient means and by which it is bent and shaped into a tube or cylinder.
  • Figure 1 is a diagrammatic view illustrating the characteristic elements of apparatus for carrying out the process accordingto the invention, applied to the production of a plug having an outerlayer of fibrous strands woven together with or without metal wires, and an inner layer of fibrous strands with or without metal wires, such strands extending longitudinally of the plug
  • Figure 2 is a diagrammatic view illustrating in plan the formation of a wall plug by the apparatus shown in Figure 1, V V
  • Figure 3 is a view similar to Figure 1, wherein the inner layer of the plug is formed by a thin metalistrip bent to the shape of a tube or cyl inder.
  • Figures 4 and 5, respectively, are diagrammaticviews illustrating the construction of the finished wall plugs produced by the apparatus shown in Figures 1 and 3.
  • the improved wall plug may comprise an inner layer formed of longitudinally arranged strands 2 of fibrous material of any suitable kind, e. g., of jute, disposed side by side upon 'a cylindrical mandrel I.
  • the strands 2 may have metal wires, e. g., thin copper wires, combined therewith, either as cores or twisted around some or allof the individual strands.
  • the outer layer of the plug is formed by strands ,3,.which may be of fibre alone, but preferably some or all of the strands 3 are combined with thin metal wires.
  • the strands 3 are led in a pressure under which the impregnating medium is supplied.
  • the improved plug passes directly from the chamber'4, in which braiding of the fibrousstrands 3" of the outer layer of the plug is completed and in whichimpregnation of the strands 3 and alsoof the strands 2 takes place, into a shaping and sizing die H], which is preferably. heated, wherebyla-rod or tube of wall plugisformed of therequired accurate dimensions and of .a true cylindrical shape, and wherebythe impregnating medium is dried and hardened
  • a plurality of suchsizing dies may be provided to reducethe diameterof the plug, if desired, so that accurate meansmay be available for the continuous production-from one machine of plugs'of differing diameters..--
  • a process for the braiding together the fibrous strandsiand the m tal wires into a ubu rstructure in said cham anufacture of wall plugs comprising feeding ap stripof sheet metalto'a shaping die whereby it is bent to form atube; leading a plurality of fibrous strands and a plurality of thin-metal wires to aisubstantially closed chamber, drawing the sheet metal tube through such chamber, maintaining a supply of impreg' nating fluid under pressure in such: chamber,
  • a process for the manufacture of tubular wall plugs comprising leadin a plurality of fibrous strands and a plurality of thin metal wires to a substantially closed chamber, maintaining a supply of impregnating fluid in such chamber, braiding together the fibrous strands with the metal wires into a tubular structure in such chamber, applying pressure to the impregnating fluid in such chamber, drawing a continuous length of impregnated tube from such chamber, drying the impregnated tube and cutting it into suitable lengths.
  • a process for the manufacture of tubular wall plugs comprising leading a plurality of fibrous strands and a plurality of thin metal wires to a substantially closed chamber, maintaining a supply of impregnating fluid in such chamber, braiding together the fibrous strands with the metal wires into a tubular structure in such chamber around a mandrel passing through such chamber, applying pressure to the impregnating fluid in such chamber, drawing a continuous length of impregnated tube from such chamber, drying the impregnated tube and cutting it into suitable lengths.
  • a process for the manufacture of tubular wall plugs comprising leading a plurality of fibrous strands and a plurality of thin metal wires to a substantially closed chamber, maintaining a supply of impregnating fluid under pressure in such chamber, braiding together the fibrous strands with the metal wires into a tubular structure in such chamber around a mandrel passing through such chamber, drawing a continuous length of impregnated tube from such chamber through a sizing and shaping die, drying the impregnated tube and cutting it into suitable lengths.
  • a process for the manufacture of tubular wall plugs comprising arranging a plurality of fibrous strands longitudinally around a cylindrical mandrel, such mandrel together with the fibrous strands arranged around it extending through a substantially closed chamber, leading into said chamber a plurality of separate fibrous strands and a plurality of separate metal Wires, maintaining a supply of heated impregnating fluid in said chamber, braiding together in said chamber said separate fibrous strands and said separate metal Wires to form a tubular structure around the fibrous strands arranged longitudinally around said mandrel, withdrawing the composite layered tubular structure from the mandrel, and cutting it into suitable lengths.
  • a process for the manufacture of tubular wall plugs comprising leading a plurality of fibrous strands and a plurality of thin metal wires to a substantially closed chamber, maintaim'ng a supply of impregnating fluid in such chamber, maintaining the said fluid under a constant pressure in such chamber, braidin together the fibrous strands with the metal wires into a tubular structure in such chamber, drawing a continuous length of impregnated tube from such chamber, drying the impregnated tube and cutting it into suitable lengths.
  • a process for the manufacture of tubular Wall plugs comprising leading a plurality of fibrous strands and a plurality of thin metal wires to a substantially closed chamber, maintaining a supply of impregnating fluid within such chamber, braiding together the fibrous strands with the metal wires into a tubular structure Within such chamber, app-lying pressure to the impregnating fluid in such chamber, drawing a continuous length of impregnated tube from such chamber through a heated sizing die, and cutting the dried and sized tube into suitable lengths.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Textile Engineering (AREA)
  • Surface Heating Bodies (AREA)
  • Ropes Or Cables (AREA)
  • Braiding, Manufacturing Of Bobbin-Net Or Lace, And Manufacturing Of Nets By Knotting (AREA)
  • Woven Fabrics (AREA)
US349524A 1939-08-19 1940-08-02 Process for the manufacture of wall plugs Expired - Lifetime US2308825A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL544885X 1939-08-19

Publications (1)

Publication Number Publication Date
US2308825A true US2308825A (en) 1943-01-19

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Application Number Title Priority Date Filing Date
US349524A Expired - Lifetime US2308825A (en) 1939-08-19 1940-08-02 Process for the manufacture of wall plugs

Country Status (3)

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US (1) US2308825A (de)
GB (1) GB544885A (de)
NL (1) NL65294C (de)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2419741A (en) * 1943-03-05 1947-04-29 George A Stone Special head with guide openings for braiding machines
US2422234A (en) * 1943-10-14 1947-06-17 Fibre Products Lab Inc Method and apparatus for producing tubular fabric
US2459688A (en) * 1946-06-01 1949-01-18 Johns Manville Insulating tubular covering and method of making the same
US2500523A (en) * 1943-03-08 1950-03-14 Dayton Rubber Company Method of manufacturing wire cord
US2500332A (en) * 1946-12-28 1950-03-14 Celanese Corp Covered and coated cord and fabric
US2602766A (en) * 1948-04-10 1952-07-08 Richard J Francis Reinforced plastic rods and methods of making same
US2649833A (en) * 1949-04-14 1953-08-25 Ashaway Line & Twine Mfg Manufacture of lines for racquets
US2684318A (en) * 1950-04-03 1954-07-20 Sam M Shobert Method for fabricating glass rods
US2712263A (en) * 1949-09-07 1955-07-05 Julian T Crandall Manufacture of strings
US2801565A (en) * 1955-07-15 1957-08-06 Edouard A Nicollet Improvements in picture wire
US2974713A (en) * 1957-06-10 1961-03-14 Porter Co Inc H K Method of continuously producing reinforced hose
US3033729A (en) * 1957-08-05 1962-05-08 Samuel M Shobert Method of continuously making glassreinforced plastic tubing
US3653295A (en) * 1970-04-30 1972-04-04 Johns Manville Method of providing a lubricant to braided cord
US5127307A (en) * 1989-09-27 1992-07-07 Gould Inc. Method of manufacture of articles employing tubular braids and resin applicator used therein
US5146835A (en) * 1988-02-02 1992-09-15 E. I. Dupont De Nemours And Company In-line consolidation of braided structures
US5993713A (en) * 1992-12-01 1999-11-30 De La Puerta; Enrique Reinforced composite shapes and method and apparatus for their manufacture
EP1792710A1 (de) * 2005-11-30 2007-06-06 Thomas GmbH + Co. Technik + Innovation KG Verfahren zur Herstellung eines verstärkten Kunststoffprofils
WO2008006345A2 (de) 2006-07-12 2008-01-17 Mht Patentverwertungs-Beteillgungs-Und Verwaltungs Gmbh Aus einer stranganordnung bestehender dübel

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3091990A (en) * 1960-03-24 1963-06-04 Harland E Mcvittie Hollow tubular spirally wound covered metallic anchor
EP0598159A1 (de) * 1992-11-18 1994-05-25 José Enrique De La Puerta Climente Verfahren zur Herstellung verstärkter Verbundformteile

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2419741A (en) * 1943-03-05 1947-04-29 George A Stone Special head with guide openings for braiding machines
US2500523A (en) * 1943-03-08 1950-03-14 Dayton Rubber Company Method of manufacturing wire cord
US2422234A (en) * 1943-10-14 1947-06-17 Fibre Products Lab Inc Method and apparatus for producing tubular fabric
US2459688A (en) * 1946-06-01 1949-01-18 Johns Manville Insulating tubular covering and method of making the same
US2500332A (en) * 1946-12-28 1950-03-14 Celanese Corp Covered and coated cord and fabric
US2602766A (en) * 1948-04-10 1952-07-08 Richard J Francis Reinforced plastic rods and methods of making same
US2649833A (en) * 1949-04-14 1953-08-25 Ashaway Line & Twine Mfg Manufacture of lines for racquets
US2712263A (en) * 1949-09-07 1955-07-05 Julian T Crandall Manufacture of strings
US2684318A (en) * 1950-04-03 1954-07-20 Sam M Shobert Method for fabricating glass rods
US2801565A (en) * 1955-07-15 1957-08-06 Edouard A Nicollet Improvements in picture wire
US2974713A (en) * 1957-06-10 1961-03-14 Porter Co Inc H K Method of continuously producing reinforced hose
US3033729A (en) * 1957-08-05 1962-05-08 Samuel M Shobert Method of continuously making glassreinforced plastic tubing
US3653295A (en) * 1970-04-30 1972-04-04 Johns Manville Method of providing a lubricant to braided cord
US5146835A (en) * 1988-02-02 1992-09-15 E. I. Dupont De Nemours And Company In-line consolidation of braided structures
US5127307A (en) * 1989-09-27 1992-07-07 Gould Inc. Method of manufacture of articles employing tubular braids and resin applicator used therein
US5993713A (en) * 1992-12-01 1999-11-30 De La Puerta; Enrique Reinforced composite shapes and method and apparatus for their manufacture
EP1792710A1 (de) * 2005-11-30 2007-06-06 Thomas GmbH + Co. Technik + Innovation KG Verfahren zur Herstellung eines verstärkten Kunststoffprofils
US20070126140A1 (en) * 2005-11-30 2007-06-07 Klaus Jansen Method of producing a reinforced plastic profile
WO2008006345A2 (de) 2006-07-12 2008-01-17 Mht Patentverwertungs-Beteillgungs-Und Verwaltungs Gmbh Aus einer stranganordnung bestehender dübel
WO2008006345A3 (de) * 2006-07-12 2008-03-27 Mht Patentverwertungs Beteillg Aus einer stranganordnung bestehender dübel
US20090279980A1 (en) * 2006-07-12 2009-11-12 Mht Patentverwertungs-Beteilgungs-Und Verwal Tungs Gmbh Dowel composed of a strand arrangement
US8821090B2 (en) * 2006-07-12 2014-09-02 Mht Patentverwertungs-, Beteiligungs-Und Verwaltungs Gmbh Dowel composed of a strand arrangement

Also Published As

Publication number Publication date
NL65294C (de)
GB544885A (en) 1942-05-01

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