Locking system for mechanical joining of floorboards and method for production thereof

A locking floorboard system for mechanical joining of floorboards, each of the floorboards having a body and an upper side of the body and a balancing layer on a rear side of the body, said system comprising:

• a first floorboard;
• a second floorboard;
• for horizontal joining of a first joint edge of the first floorboard to a second joint edge of the second floorboard at a vertical joint plane, a locking groove which is formed in an underside of said second floorboard and extending parallel with and at a distance from said vertical joint plane at said second joint edge and, a strip integrally formed with the body of said first floorboard, which strip at said first joint edge projects from said vertical joint plane and supports a locking element, which locking element projects towards a plane containing the upper side of said first floorboard and which locking element has a locking surface for coaction with said locking groove, and
• for vertical joining of the first joint edge and the second joint edge, a tongue on the second floorboard which at least partly projects and extends from the vertical joint plane and, a tongue groove in the first floorboard adapted to coact with said tongue, the first and second floorboards having coacting upper and coacting lower contact surfaces, the upper and lower coacting contact surfaces comprise surface portions in said tongue groove and on said tongue, the upper and lower contact surfaces are essentially plane-parallel and extend essentially parallel with a plane containing the upper side of the floorboards, and
• the upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below the upper contact surface and above the lower contact surface,
• wherein the relationship T−(P1+0.3*P2)>P3, where
• T=thickness of the floorboard,
• P1=distance between the upper side of the floorboard and said upper contact surface, measured in the thickness direction of the floorboard,
• P2=distance between said upper and lower contact surfaces measured in the thickness direction of the floorboard, and
• P3=distance between the upper edge of the locking element closest to the upper side of the floorboard and the underside of the floorboard,
• wherein the relationship P3>0.3*T.

A locking floorboard system for mechanical joining of floorboards, each of the floorboards having a body and an upper side of the body and a balancing layer on a rear side of the body, said system comprising:

• a first floorboard;
• a second floorboard;
• for horizontal joining of a first joint edge of the first floorboard to a second joint edge of the second floorboard at a vertical joint plane, a locking groove which is formed in an underside of said second floorboard and extending parallel with and at a distance from said vertical joint plane at said second joint edge and, a strip integrally formed with the body of said first floorboard, which strip at said first joint edge projects from said vertical joint plane and supports a locking element, which locking element projects towards a plane containing the upper side of said first floorboard and which locking element has a locking surface for coaction with said locking groove, and
• for vertical joining of the first joint edge and the second joint edge, a tongue on the second floorboard which at least partly projects and extends from the vertical joint plane and, a tongue groove in the first floorboard adapted to coact with said tongue, the first and second floorboards having coacting upper and coacting lower contact surfaces, the upper and lower coacting contact surfaces comprise surface portions in said tongue groove and on said tongue, the upper and lower contact surfaces are essentially plane-parallel and extend essentially parallel with a plane containing the upper side of the floorboards, and
• the upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below the upper contact surface and above the lower contact surface,
• wherein the relationship T−(P1+0.3*P2)>P3, where
• T=thickness of the floorboard,
• P1=distance between the upper side of the floorboard and said upper contact surface, measured in the thickness direction of the floorboard,
• P2=distance between said upper and lower contact surfaces measured in the thickness direction of the floorboard, and
• P3=distance between the upper edge of the locking element closest to the upper side of the floorboard and the underside of the floorboard,
• wherein there is a gap between the upper side of the locking element and the bottom of the locking groove.

A locking floorboard system for mechanical joining of floorboards, each of the floorboards having a body and an upper side of the body and a balancing layer on a rear side of the body, said system comprising:

• a first floorboard;
• a second floorboard;
• for horizontal joining of a first joint edge of the first floorboard to a second joint edge of the second floorboard at a vertical joint plane, a locking groove which is formed in an underside of said second floorboard and extending parallel with and at a distance from said vertical joint plane at said second joint edge and, a strip integrally formed with the body of said first floorboard, which strip at said first joint edge projects from said vertical joint plane and supports a locking element, which locking element projects towards a plane containing the upper side of said first floorboard and which locking element has a locking surface for coaction with said locking groove, and
• for vertical joining of the first joint edge and the second joint edge, a tongue on the second floorboard which at least partly projects and extends from the vertical joint plane and, a tongue groove in the first floorboard adapted to coact with said tongue, the first and second floorboards having coacting upper and coacting lower contact surfaces, the upper and lower coacting contact surfaces comprise surface portions in said tongue groove and on said tongue, the upper and lower contact surfaces are essentially plane-parallel and extend essentially parallel with a plane containing the upper side of the floorboards, and
• the upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below the upper contact surface and above the lower contact surface,
• wherein the relationship T−(P1+0.3*P2)>P3, where
• T=thickness of the floorboard,
• P1=distance between the upper side of the floorboard and said upper contact surface, measured in the thickness direction of the floorboard,
• P2=distance between said upper and lower contact surfaces measured in the thickness direction of the floorboard, and
• P3=distance between the upper edge of the locking element closest to the upper side of the floorboard and the underside of the floorboard,
• wherein there is a gap between the side of the locking element furthest away from the joint plane and the edge of the locking groove furthest away from the joint plane.

A locking floorboard system for mechanical joining of floorboards, each of the floorboards having a body and an upper side of the body and a balancing layer on a rear side of the body, said system comprising:

• a first floorboard;
• a second floorboard;
• for horizontal joining of a first joint edge of the first floorboard to a second joint edge of the second floorboard at a vertical joint plane, a locking groove which is formed in an underside of said second floorboard and extending parallel with and at a distance from said vertical joint plane at said second joint edge and, a strip integrally formed with the body of said first floorboard, which strip at said first joint edge projects from said vertical joint plane and supports a locking element, which locking element projects towards a plane containing the upper side of said first floorboard and which locking element has a locking surface for coaction with said locking groove, and
• for vertical joining of the first joint edge and the second joint edge, a tongue on the second floorboard which at least partly projects and extends from the vertical joint plane and, a tongue groove in the first floorboard adapted to coact with said tongue, the first and second floorboards having coacting upper and coacting lower contact surfaces, the upper and lower coacting contact surfaces comprise surface portions in said tongue groove and on said tongue, the upper and lower contact surfaces are essentially plane-parallel and extend essentially parallel with a plane containing the upper side of the floorboards, and
• the upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below the upper contact surface and above the lower contact surface,
• wherein the relationship T−(P1+0.3*P2)>P3, where
• T=thickness of the floorboard,
• P1=distance between the upper side of the floorboard and said upper contact surface, measured in the thickness direction of the floorboard,
• P2=distance between said upper and lower contact surfaces measured in the thickness direction of the floorboard, and
• P3=distance between the upper edge of the locking element closest to the upper side of the floorboard and the underside of the floorboard,
• wherein the locking element has an operative locking surface for coaction with a corresponding operative locking surface of the locking groove, and that these operative locking surfaces are inclined at such an angle relative to a plane containing the underside of the floorboard that the locking surfaces extend essentially tangentially relative to a circular arc having a centre where the vertical joint plane intersects the upper side of the floorboard, seen in a section perpendicular to said joint plane and perpendicular to the floorboards.

A locking floorboard system for mechanical joining of floorboards, each of the floorboards having a body and an upper side of the body and a lower side of the body, said system comprising:

• a first floorboard;
• a second floorboard;
• for horizontal joining of a first joint edge of the first floorboard to a second joint edge of the second floorboard at a vertical joint plane, a locking groove which is formed in an underside of said second floorboard and extending parallel with and at a distance from said vertical joint plane at said second joint edge and, a strip formed with the body of said first floorboard, which strip at said first joint edge projects from said vertical joint plane and supports a locking element, which locking element projects towards a plane containing the upper side of said first floorboard and which locking element has a locking surface for coaction with said locking groove, wherein the strip is formed in one piece with the body of the first floorboard and
• for vertical joining of the first joint edge and the second joint edge, a tongue on the second floorboard which at least partly projects and extends from the vertical joint plane and, a tongue groove in the first floorboard adapted to coact with said tongue, the first and second floorboards having coacting upper and coacting lower contact surfaces, the upper and lower coacting contact surfaces comprise surface portions in said tongue groove and on said tongue, the upper and lower contact surfaces are essentially plane-parallel and extend essentially parallel with a plane containing the upper side of the floorboards, and
• the upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below the upper contact surface and above the lower contact surface.

A thin floating floor board including an upper surface layer, a body layer arranged beneath the upper surface layer, a lower balancing layer, and a mechanical locking system for locking a first edge of a first floor board to a second edge of an identical second floor board, the mechanical locking system comprising:

• a tongue and groove on the first edge and the second edge forming a first mechanical connection locking the first and second edges to each other in a first direction at right angles to a principal plane of the floor boards, the tongue and groove being formed in the material of the body layer;
• and
• a locking device arranged on an underside of the first and the second edges, the locking device forming a second mechanical connection locking the first and the second edges to each other in a second direction parallel to the principal plane and at right angles to the edges,
• wherein the looking device includes a locking groove which extends parallel to and spaced from the second edge, the locking groove being open at the underside of the second edge and including an internal surface,
• wherein the locking device further includes a strip extending from the first edge, the strip extending throughout substantially an entire length of the first edge and being provided with a locking element projecting from the strip,
• wherein the strip, the locking element, and the locking groove are configured such that when the second edge is pressed against an upper part of the first edge and is then angled down, the locking element can enter the locking groove,
• wherein the locking element has a locking surface which faces the first edge and is configured so as to contact the internal surface of the locking groove to prevent substantial separation of the joined first and second edges, and
• wherein an upper edge of the locking element is located in a horizontal plane, which horizontal plane is positioned below an upper contact surface of the first mechanical connection and above the lower contact surface of the first mechanical connection.