Locking joint for joining structural members

• US 8,864,407 B1
• Filed: 03/17/2011
• Issued: 10/21/2014
• Est. Priority Date: 03/17/2011
• Status: Expired due to Fees

• Current Assignee: Petter Sorum
• Original Assignee: Petter Sorum
• Inventors: Sorum, Petter
• Primary Examiner(s): Stodola, Daniel P
• Assistant Examiner(s): McMahon, Matthew R
• Application Number:
  US13/050,322
• Time in Patent Office: 1,314 Days
• Field of Search: 403/241, 403/245, 403/246, 403/263, 403/360, 403/375, 403/381, 403/382, 403/383, 525/901, 525/902, 525/903, 525/924, 525/925, 522/922, 522/923, 522/926, 211/103, 211/190, 108/109, 108/110, 108/147.17, 108/158.12, 108/108, 248/223.41
• US Class Current: 403/381
• CPC Class Codes: A47B 2230/0081 Mortise and tenon type joints with some general male and female joints
• CPC Class Codes: A47B 2230/0096 Assembling sheet parts by male and female parts formed in the sheet thickness
• CPC Class Codes: A47B 47/0075 Flat or flat-like panels connected without frames for panels mainly made of wood or plastic A47B47/042
• CPC Class Codes: F16B 12/125 using mortise and tenon joints
• CPC Class Codes: F16B 12/42 connecting furniture tubing to non-tubular parts connecting table tops to underframes A47B13/003
• CPC Class Codes: F16B 2200/30 Dovetail-like connections
• CPC Class Codes: F16B 2200/67 Rigid angle couplings
• CPC Class Codes: F16B 5/008 by a rotating or sliding and rotating movement
• CPC Class Codes: F16B 7/22 using hooks or like elements
• CPC Class Codes: Y10T 403/4602 Corner joint

Abstract

A furniture interconnection system for reversibly joining a board element and an upright element perpendicular to each other in a furniture frame. The joint is formed by a tenon and a mortise, the tenon having a novel irregular hexagon shape, the mortise having a novel irregular quadrilateral shape. The tenon is inserted into the mortise and pivoted in stages on a pair of angles of the hexagon, to form a stable joint without fasteners such as glue, screws, and other similar fasteners. As the tenon pivots inside the mortise, pairs of complementary and supplementary angles interact within the furniture interconnection system to position the tenon to form the stable joint without additional fasteners, allowing the furniture frame to be easily dismantled for moving or reconfiguration without damaging the frame, but forming the reversible joint that is sufficiently sturdy to support the load it was designed to bear.

Claims

1. An interlocking joint in a furniture interconnection system for reversibly connecting a furniture frame board element having at least one end perpendicularly to a furniture frame upright element, comprising:

an irregular quadrilateral mortise, the mortise a cavity cut into the upright element, wherein the mortise has a top portion and a bottom portion that form one continuous cavity including a front opening at the bottom portion, the bottom portion having a square shape that includes the front opening and abuts the top portion such that the top portion forms an isosceles right triangle shape with the bottom portion; and

an irregular substantially hexagonal tenon on the end of the board element, the tenon has a top right angle, and four angles each of approximately one hundred thirty-five degrees, the tenon for inserting into the mortise with the board element substantially parallel to the upright frame element and pivoting inside the mortise until the board element is perpendicular to the upright frame element, forming a reversible interlocking joint for connecting the board element to the frame element;

wherein, when the tenon is interlocked into the mortise, the tenon and the mortise define a pair of spaced apart gaps between the tenon and the mortise, each gap having the shape of a smaller isosceles right triangle.

2. The interlocking joint as described in claim 1, wherein the interlocking joint has a locking system, the locking system having a key pin and a groove, the groove cut into the upright element, the upright element having a pair of opposing sides, a first side having the opening of the mortise and a second side having an opening for the groove, the groove cut into the upright element opposite the mortise and extending through the rear of the mortise into the bottom portion of the mortise and through the bottom of the mortise, the key pin inserting into the groove and extending into the mortise when the joint is formed, preventing the tenon from pivoting inside the mortise and dismantling the joint.

3. The interlocking joint as described in claim 2, wherein the groove has an opening, a bottom, and parallelogram shape, the parallelogram shape having a pair of parallel sides, a first short side, a second parallel long side, and a pair of equal sides of equal length connecting the parallel sides, a first equal side defining the opening of the groove and a second equal side defining the bottom of the groove, the groove having a first pair of angles connecting the short side to each of the equal sides, the pair of angles each equaling approximately one hundred thirty-five degrees, the key pin having a second pair of angles connecting the long side to each of the equal sides, the pair of angles each equaling approximately forty-five degrees.

4. The interlocking joint as described in claim 2, wherein the key pin has a parallelogram shape, the parallelogram shape having a pair of parallel sides, a first short side, a second parallel long side, and a pair of equal sides of equal length connecting the parallel sides, the key pin having a first pair of angles connecting the short side to each of the equal sides, the pair of angles each equaling approximately one hundred thirty-five degrees, the key pin having a second pair of angles connecting the long side to each of the equal sides, the pair of angles each equaling approximately forty-five degrees.

5. The interlocking joint as described in claim 4, wherein the key and the groove have a plurality of angles, each angle having an integer multiple of forty-five degrees, such that the plurality of angles form a plurality of pairs that are supplementary when the key pin is inserted into the groove extending into the mortise and locking the tenon in place.

6. The interlocking joint as described in claim 1, wherein the board element has a pair of ends, each end having a tenon, the board element connecting to a pair of upright elements, each having the mortise, each tenon and mortise forming an interlocking joint connecting the board element perpendicularly to the pair of upright elements, and a construction lock having a horizontal element having a pair of ends further connecting the pair of upright elements, an end of the horizontal element connected to each upright element, further preventing rotating the upright elements to dismantle the joint.

7. An interlocking joint in a furniture interconnection system for reversibly connecting a furniture frame board element having an end, perpendicularly to a furniture frame upright element, comprising:

an irregular quadrilateral mortise, the mortise a cavity cut into the upright element, the mortise having a top portion and a bottom portion, the top portion and bottom portion forming one continuous cavity, the top portion having a top, the bottom cavity including a front opening, the bottom portion having a square shape and the top portion having an isosceles right triangle shape having a pair of acute angles of approximately forty-five degrees one of said acute angles at the top of the mortise; and

an irregular substantially hexagonal tenon on the end of the board element, the tenon having a top and a bottom, four angles, each approximately one hundred thirty-five degrees, and a top right angle, the tenon for inserting into the mortise with the board element substantially parallel to the upright element and pivoting inside the mortise until the board element is perpendicular to the upright frame element, forming a reversible interlocking joint connecting the board element to the frame element wherein, when the tenon is interlocked into the mortise, the tenon and the mortise define a pair of spaced apart gaps between the tenon and the mortise, each gap having the shape of a smaller isosceles right triangle.