US3385002A - Hollow core door - Google Patents

Hollow core door Download PDF

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Publication number
US3385002A
US3385002A US534199A US53419966A US3385002A US 3385002 A US3385002 A US 3385002A US 534199 A US534199 A US 534199A US 53419966 A US53419966 A US 53419966A US 3385002 A US3385002 A US 3385002A
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United States
Prior art keywords
core
frame
door
laths
secured
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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
US534199A
Inventor
Edward G Quinif
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Walled Lake Door Co
Original Assignee
Walled Lake Door Co
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Publication date
Application filed by Walled Lake Door Co filed Critical Walled Lake Door Co
Priority to US534199A priority Critical patent/US3385002A/en
Application granted granted Critical
Publication of US3385002A publication Critical patent/US3385002A/en
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Expired - Lifetime legal-status Critical Current

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    • E—FIXED CONSTRUCTIONS
    • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
    • E06B3/00—Window sashes, door leaves, or like elements for closing wall or like openings; Layout of fixed or moving closures, e.g. windows in wall or like openings; Features of rigidly-mounted outer frames relating to the mounting of wing frames
    • E06B3/70—Door leaves
    • E06B3/7015—Door leaves characterised by the filling between two external panels
    • E06B3/7017—Door leaves characterised by the filling between two external panels of grating type
    • E—FIXED CONSTRUCTIONS
    • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
    • E06B3/00—Window sashes, door leaves, or like elements for closing wall or like openings; Layout of fixed or moving closures, e.g. windows in wall or like openings; Features of rigidly-mounted outer frames relating to the mounting of wing frames
    • E06B3/70—Door leaves
    • E06B3/82—Flush doors, i.e. with completely flat surface
    • E06B3/822—Flush doors, i.e. with completely flat surface with an internal foursided frame
    • E—FIXED CONSTRUCTIONS
    • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
    • E06B3/00—Window sashes, door leaves, or like elements for closing wall or like openings; Layout of fixed or moving closures, e.g. windows in wall or like openings; Features of rigidly-mounted outer frames relating to the mounting of wing frames
    • E06B3/70—Door leaves
    • E06B2003/7046—Door leaves with provisions for locks, hinges or other fittings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/23—Sheet including cover or casing
    • Y10T428/234—Sheet including cover or casing including elements cooperating to form cells

Definitions

  • the hollow core door of this invention comprises a border frame, a core within the frame, and outer panels secured to opposite sides of the frame and confining the core within the frame.
  • the core is composed of a plurality of interconnected laths and is extended to a stressed position wherein the laths move apart to form an open cellular structure.
  • a door according to the invention utilizes an extendable strengthening core formed from a plural y of flexible laths or slats.
  • the core laths lie flat against each other so that the core is compact and easily handled.
  • the laths are flexed apart so as to form a tier of lenticularly shaped support cells within the door frame.
  • a given lath may be fitted into various size door frames by suitably flexing the lath components so that the core fills the frame.
  • the elastically stressed slats assure that the core is properly and uniformly spaced within the frame.
  • the sides of the lath core members and frame are secured to the side panels to complete an integral strong and durable door having high resistance to warpage or other structural deformation.
  • an object of the invention is to provide a new and improved flush door.
  • Another object is to provide a fiush door having an improved strengthening core member.
  • a further object is to provide a novel cellular strengthening core for use in a construction unit.
  • FIGURE 1 is a partially broken away perspective view of a flush door constructed according to the invention
  • FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1;
  • FIGURE 3 is a sectional view taken along line 33 of FIGURE 1.
  • a flush door according to the invention includes an integral frame made up side frame members 12 and 14 and top and bottom frame members 16 and 18.
  • Mounting blocks 20 may be secured to the inside of the frame on side frame members 12 and 14 to facilitate the mounting of latch means on the door.
  • Side panels 22 and 24 are fitted on either side of the frame and define an interior space filled by cellular core 26.
  • the core is made up from a plurality of aligned elongate flexible laths or lath members 28.
  • the laths 28 may be made of wood, plastic, metal or other suitable material.
  • each lath 28 is secured .at 30 to both ends of one of the adjacent laths and is secured at 32 to the middle portion of the other adjacent lath so as to form the core 26.
  • the core 26 is usually assembled with the laths 28 lying flat upon each other. In this collapsed position the core 26 is relatively compact for ease in handling and storage.
  • cores 26 In the mass construction of cores 26 it may be desirable to form the cores 26 from sheets of lath material having an approapriate lath width. In this case the sheets are piled one upon another and pairs of adjacent sheets are secured together at the side edges thereof as an example, with glue or other fastening means. The outer central portions of such pairs lying between the lateral edges thereof are also secured together. Individual cores are sliced from one end of the assembled sheets of lath material.
  • the frame is first formed and then a core 26 having an appropriate width is extended and fitted within the frame by attaching the top and bottom laths to the top and bottom frame members 16 and 18. Extension of the core 26 forms a tier of lenticularly shaped support cells running from the top to the bottom of the door frame.
  • the elastic deformation of the laths assures that the core 26 is uniformly and accurately positioned within the frame to provide a uniformly reinforced flush door 10.
  • the flexibility of the laths also assures that laths 34 are properly seated on the ends of the blocks 20.
  • a working clearance 36 is provided between the ends of the laths 28 and the frame side walls 12 and 14 and block 20 to facilitate insertion of the core 26 within the frame.
  • the door is completed by gluing or otherwise securing the side panels 22 and 24 to the edges of the frame and core laths, thus forming a rigid one-piece hollow flush door.
  • the type of core disclosed herein is particularly advantageous for use in the manufacture of flush doors since a given core can be extended, within the limits defined by the flexibility of the laths 28, to fit within various sized .door frames.
  • This flexibility in core utility eliminates the necessity of providing a different core for each size door frame.
  • the Strength of the door is dependent upon the number or density of support cells in the core unit. The use of a core having a large number of relatively closely spaced support cells results in a stronger door'than when a core having a smaller number of cells is used.
  • the drawing discloses a flush type door with a strengthening core 26 having horizontally oriented support cells extending across the width of the door. It is sometimes desirable to use a strengthening core having vertically extending support cells running from the top to the bottom of the door interior. When using such a core it is preferable to provide at least three support cells in the core in order to assure proper strengthening of the door.
  • a hollow core door comprising an elongated rectangular border frame, mounting blocks secured to the inner edges of the sides of said frame intermediate the ends of the latter in opposed relation to one another, a core composed of a plurality of elongated, thin generally parallel flexible laths oriented in side-by-side relation at right angles to a reference plane, each lath being secured to two immediately adjacent laths with the ends thereof secured in surface-to-surface relation to the ends of one of said adjacent laths and the center thereof secured in surface-to-surface relation to the center of the other of said adjacent laths, said core being extended from a relaxed position wherein the la hs lie fiat against each other to a stressed position.
  • the laths are moved apart to form a tier of lenticular support cells, each cell being defined by one lath and said one adjacent lath, sa d stressed core being disposed in the plane and occupying the interior of said frame with said tier running between opposed ends of said frame and said laths extending laterally between the sides of said frame, the ends of said laths above and below said blocks terminating closely adjacent the inner edges of the sides of said frame, the ends of the laths immediately above and below said blocks being flexibly seated on the ends of said blocks, the ends of said laths extending between said blocks terminating closely adjacent the inner edges of said blocks, and the uppermost and lowermost laths being centrally secured to the inner edges of the upper and lower ends respectively of said frame, and outer panels abutting and secured to opposite sides of said frame and to opposite edges of said laths.

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  • Engineering & Computer Science (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Securing Of Glass Panes Or The Like (AREA)

Description

United States Patent Office 3,385,fi2 Patented May 28, 1968 3,385,002 HGLLOW C(IRE [300R Edward G. Quinif, Farmington, Mich. Walled Lake Door Co., 19335 Beech-Daily Road, Detroit, Mich. 48240) Filed Mar. 14, 1966, Ser. No. 534,199 1 Claim. (Cl. 49-601) ABSTRACT OF THE DISCLOSURE The hollow core door of this invention comprises a border frame, a core within the frame, and outer panels secured to opposite sides of the frame and confining the core within the frame. The core is composed of a plurality of interconnected laths and is extended to a stressed position wherein the laths move apart to form an open cellular structure.
This invention relates to a core type construction unit and has particular reference to a new and improved hollow core door. A door according to the invention utilizes an extendable strengthening core formed from a plural y of flexible laths or slats. In the collapsed position prior to insertion within the door frame, the core laths lie flat against each other so that the core is compact and easily handled. When the core is extended and positioned Within the door frame, the laths are flexed apart so as to form a tier of lenticularly shaped support cells within the door frame. A given lath may be fitted into various size door frames by suitably flexing the lath components so that the core fills the frame. The elastically stressed slats assure that the core is properly and uniformly spaced within the frame. The sides of the lath core members and frame are secured to the side panels to complete an integral strong and durable door having high resistance to warpage or other structural deformation.
Accordingly an object of the invention is to provide a new and improved flush door.
Another object is to provide a fiush door having an improved strengthening core member.
A further object is to provide a novel cellular strengthening core for use in a construction unit.
Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawing illustrating a preferred embodiment of the invention, wherein:
FIGURE 1 is a partially broken away perspective view of a flush door constructed according to the invention;
FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1; and
FIGURE 3 is a sectional view taken along line 33 of FIGURE 1.
A flush door according to the invention includes an integral frame made up side frame members 12 and 14 and top and bottom frame members 16 and 18. Mounting blocks 20 may be secured to the inside of the frame on side frame members 12 and 14 to facilitate the mounting of latch means on the door. Side panels 22 and 24 are fitted on either side of the frame and define an interior space filled by cellular core 26.
The core is made up from a plurality of aligned elongate flexible laths or lath members 28. Depending upon the type of door or construction unit in which the core is used, the laths 28 may be made of wood, plastic, metal or other suitable material. As shown in FIGURE 1, each lath 28 is secured .at 30 to both ends of one of the adjacent laths and is secured at 32 to the middle portion of the other adjacent lath so as to form the core 26. The core 26 is usually assembled with the laths 28 lying flat upon each other. In this collapsed position the core 26 is relatively compact for ease in handling and storage.
In the mass construction of cores 26 it may be desirable to form the cores 26 from sheets of lath material having an approapriate lath width. In this case the sheets are piled one upon another and pairs of adjacent sheets are secured together at the side edges thereof as an example, with glue or other fastening means. The outer central portions of such pairs lying between the lateral edges thereof are also secured together. Individual cores are sliced from one end of the assembled sheets of lath material.
In the assembly of a flush door 10 according to the invention, the frame is first formed and then a core 26 having an appropriate width is extended and fitted within the frame by attaching the top and bottom laths to the top and bottom frame members 16 and 18. Extension of the core 26 forms a tier of lenticularly shaped support cells running from the top to the bottom of the door frame. The elastic deformation of the laths assures that the core 26 is uniformly and accurately positioned within the frame to provide a uniformly reinforced flush door 10. The flexibility of the laths also assures that laths 34 are properly seated on the ends of the blocks 20. A working clearance 36 is provided between the ends of the laths 28 and the frame side walls 12 and 14 and block 20 to facilitate insertion of the core 26 within the frame.
When the core is properly positioned within the frame, the door is completed by gluing or otherwise securing the side panels 22 and 24 to the edges of the frame and core laths, thus forming a rigid one-piece hollow flush door.
The type of core disclosed herein is particularly advantageous for use in the manufacture of flush doors since a given core can be extended, within the limits defined by the flexibility of the laths 28, to fit within various sized .door frames. This flexibility in core utility eliminates the necessity of providing a different core for each size door frame. The Strength of the door is dependent upon the number or density of support cells in the core unit. The use of a core having a large number of relatively closely spaced support cells results in a stronger door'than when a core having a smaller number of cells is used.
The drawing discloses a flush type door with a strengthening core 26 having horizontally oriented support cells extending across the width of the door. It is sometimes desirable to use a strengthening core having vertically extending support cells running from the top to the bottom of the door interior. When using such a core it is preferable to provide at least three support cells in the core in order to assure proper strengthening of the door.
It should be noted that while the invention has been described in terms of a hollow flush door construction, it is obvious that the core described herein may be used in any of a variety of construction units wherein it is desirable to strengthen the unit by means of a core member.
What I claim as my invention is:
1. A hollow core door comprising an elongated rectangular border frame, mounting blocks secured to the inner edges of the sides of said frame intermediate the ends of the latter in opposed relation to one another, a core composed of a plurality of elongated, thin generally parallel flexible laths oriented in side-by-side relation at right angles to a reference plane, each lath being secured to two immediately adjacent laths with the ends thereof secured in surface-to-surface relation to the ends of one of said adjacent laths and the center thereof secured in surface-to-surface relation to the center of the other of said adjacent laths, said core being extended from a relaxed position wherein the la hs lie fiat against each other to a stressed position. wherein the laths are moved apart to form a tier of lenticular support cells, each cell being defined by one lath and said one adjacent lath, sa d stressed core being disposed in the plane and occupying the interior of said frame with said tier running between opposed ends of said frame and said laths extending laterally between the sides of said frame, the ends of said laths above and below said blocks terminating closely adjacent the inner edges of the sides of said frame, the ends of the laths immediately above and below said blocks being flexibly seated on the ends of said blocks, the ends of said laths extending between said blocks terminating closely adjacent the inner edges of said blocks, and the uppermost and lowermost laths being centrally secured to the inner edges of the upper and lower ends respectively of said frame, and outer panels abutting and secured to opposite sides of said frame and to opposite edges of said laths.
References Cited UNITED STATES PATENTS KENNETH DOWNEY, Primary Examiner.
US534199A 1966-03-14 1966-03-14 Hollow core door Expired - Lifetime US3385002A (en)

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2096871A1 (en) * 1970-07-08 1972-03-03 Onera (Off Nat Aerospatiale)
US4030265A (en) * 1975-10-24 1977-06-21 Allgood Jay R Arch beams and plates
US4064655A (en) * 1975-10-16 1977-12-27 Weyant Romer G Door and method of making same
US5766774A (en) * 1994-06-20 1998-06-16 Masonite Corporation Molded core component
US5875609A (en) * 1997-05-12 1999-03-02 Quinif; Edward G. Expandable spacer cores for panel doors and the method of making same
US5875608A (en) * 1997-03-17 1999-03-02 Quinif; Edward G. Expandable spacer cores for flush doors and the method of making same
US5887402A (en) * 1995-06-07 1999-03-30 Masonite Corporation Method of producing core component, and product thereof
US5992127A (en) * 1997-05-12 1999-11-30 Quinif; Edward G. Universal expandable spacer cores for hollow doors and the method of making same
US6132836A (en) * 1997-03-17 2000-10-17 Quinif; Edward G. Corrugated structural paper fillers for the interior areas of hollow doors and the method of making same
WO2000063508A1 (en) * 1999-04-15 2000-10-26 Greif Bros. Corporation Multi-panel hollow door structures and manufacturing methods employing paperboard cores
US6302472B1 (en) * 1998-01-13 2001-10-16 Sommer Allibert-Lignotock Gmbh Vehicle door
US20030168769A1 (en) * 2002-03-06 2003-09-11 Walsh John Peter Method of producing core component, and product thereof
US20070251160A1 (en) * 2003-12-19 2007-11-01 Tuff Shed, Inc. Door system for a building
US9777532B2 (en) * 2014-03-20 2017-10-03 Masonite Corporation Double backbone core for automated door assembly line, door comprising same and method of using same
US9790734B1 (en) 2013-08-02 2017-10-17 American Containers, Inc. Interior reinforcing structure for a door and method of installing an interior reinforcing structure in a door
US10301869B1 (en) * 2010-11-23 2019-05-28 Jerry G. Crittenden Hollow core door for preventing pressure build up having a prefabricated center panel and method of making the door
US10556413B2 (en) 2015-09-11 2020-02-11 JELD-WEN UK, Ltd. Method for assembly of recessed panel doors
US20210309001A1 (en) * 2018-07-25 2021-10-07 James Warren GERE Core and method for automated hollow door and panel assembly
US11274489B2 (en) * 2019-05-23 2022-03-15 Masonite Corporation Doors containing core inserts, and method of making the same
US11559917B2 (en) 2020-05-08 2023-01-24 Jeld-Wen, Inc. Drop roller press and method of making recessed panel doors

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB625036A (en) * 1946-06-24 1949-06-21 Walter Frederick Baker Improvements in or relating to cellular panelling or like cellular constructional work
US2608500A (en) * 1947-12-06 1952-08-26 Douglas Aircraft Co Inc Structural element
US3296059A (en) * 1963-03-18 1967-01-03 Benjamin W Schwindt Expansible hollow core

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB625036A (en) * 1946-06-24 1949-06-21 Walter Frederick Baker Improvements in or relating to cellular panelling or like cellular constructional work
US2608500A (en) * 1947-12-06 1952-08-26 Douglas Aircraft Co Inc Structural element
US3296059A (en) * 1963-03-18 1967-01-03 Benjamin W Schwindt Expansible hollow core

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2096871A1 (en) * 1970-07-08 1972-03-03 Onera (Off Nat Aerospatiale)
US4064655A (en) * 1975-10-16 1977-12-27 Weyant Romer G Door and method of making same
US4030265A (en) * 1975-10-24 1977-06-21 Allgood Jay R Arch beams and plates
US5766774A (en) * 1994-06-20 1998-06-16 Masonite Corporation Molded core component
US5887402A (en) * 1995-06-07 1999-03-30 Masonite Corporation Method of producing core component, and product thereof
US5875608A (en) * 1997-03-17 1999-03-02 Quinif; Edward G. Expandable spacer cores for flush doors and the method of making same
US6132836A (en) * 1997-03-17 2000-10-17 Quinif; Edward G. Corrugated structural paper fillers for the interior areas of hollow doors and the method of making same
US5875609A (en) * 1997-05-12 1999-03-02 Quinif; Edward G. Expandable spacer cores for panel doors and the method of making same
US5992127A (en) * 1997-05-12 1999-11-30 Quinif; Edward G. Universal expandable spacer cores for hollow doors and the method of making same
US6302472B1 (en) * 1998-01-13 2001-10-16 Sommer Allibert-Lignotock Gmbh Vehicle door
WO2000063508A1 (en) * 1999-04-15 2000-10-26 Greif Bros. Corporation Multi-panel hollow door structures and manufacturing methods employing paperboard cores
US6170224B1 (en) * 1999-04-15 2001-01-09 Greif Bros. Corporation Multi-panel hollow door structures and manufacturing methods employing paperboard cores
US20030168769A1 (en) * 2002-03-06 2003-09-11 Walsh John Peter Method of producing core component, and product thereof
US6764625B2 (en) 2002-03-06 2004-07-20 Masonite Corporation Method of producing core component, and product thereof
US20070251160A1 (en) * 2003-12-19 2007-11-01 Tuff Shed, Inc. Door system for a building
US7462657B2 (en) * 2003-12-19 2008-12-09 Tuff Shed, Inc. Door system for a building
US10301869B1 (en) * 2010-11-23 2019-05-28 Jerry G. Crittenden Hollow core door for preventing pressure build up having a prefabricated center panel and method of making the door
US9790734B1 (en) 2013-08-02 2017-10-17 American Containers, Inc. Interior reinforcing structure for a door and method of installing an interior reinforcing structure in a door
US9777532B2 (en) * 2014-03-20 2017-10-03 Masonite Corporation Double backbone core for automated door assembly line, door comprising same and method of using same
US10202799B2 (en) 2014-03-20 2019-02-12 Masonite Corporation Double backbone core for automated door assembly line, door comprising same and method of using same
US10556413B2 (en) 2015-09-11 2020-02-11 JELD-WEN UK, Ltd. Method for assembly of recessed panel doors
US11376834B2 (en) 2015-09-11 2022-07-05 JELD-WEN UK, Ltd. System for assembly of recessed panel doors
US20210309001A1 (en) * 2018-07-25 2021-10-07 James Warren GERE Core and method for automated hollow door and panel assembly
US11274489B2 (en) * 2019-05-23 2022-03-15 Masonite Corporation Doors containing core inserts, and method of making the same
US11773643B2 (en) 2019-05-23 2023-10-03 Masonite Corporation Doors containing core inserts, and method of making the same
US11559917B2 (en) 2020-05-08 2023-01-24 Jeld-Wen, Inc. Drop roller press and method of making recessed panel doors

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