A wooden spring, a method and a helical dryer for making the wooden spring, a wooden spring fabric and a use of the wooden spring

A wooden spring formed of a strip of wood for forming wooden spring fabric, wherein the wooden spring has a homogeneous shape, the wooden springs are interlaceable side by side with at least two other wooden springs and the wooden spring comprises:

• a helix having a first end and a second end, wherein the first end has a diameter and the second end has a diameter, and
• a plurality of coils between the first end and the second end of the helix, wherein:
• an average thickness of the helix is 0.2 to 2.0 millimeters (mm);
• an average width of the helix is 2 to 10 mm;
• an average diameter of the coil is 6 to 60 mm;
• an average pitch of the coil is 4 to 40 mm;
• and
• a stretched-out length of the wooden spring is 10 to 5000 mm.

A helix dryer for making a wooden spring having a homogeneous shape, wherein the wooden springs are interlaceable side by side with at least two other wooden springs for forming wooden spring fabric, the helix dryer comprising:

• a tubular spring forming means having a first end and a second end and comprising a helical groove formed on an outer surface of the tubular spring forming means;
• a heat source adapted to heat the tubular spring forming means to 60 to 300 degrees Celsius;
• and
• a drive mechanism comprising one or more transmission means, in the form of a belt or chain, attached around the tubular spring forming means and a drive adapted to move the one or more transmission means along the helical groove of the spring shape forming means to drag a strip of wood between the transmission means and a bottom of the helical groove of the tubular spring forming means and to pull the strip of wood along the helical groove and wind the strip of wood into a wooden spring.

A method for making a wooden spring for forming wooden spring fabric, wherein the wooden springs are interlaced with at least two side by side wooden springs to form a wooden spring fabric, the method comprising:

• cutting from a wood material a strip of wood;
• automatically determining a category of the strip of wood, controlled by a machine vision system, wherein the determining comprises:
• obtaining a digital information of the strip of wood by photographing the strip of wood;
• analyzing the digital information in an automated sorting system by a machine vision;
• and
• based on the analyzed digital information, allocating to the strip of wood one or more categories and sorting the strip of wood based on the allocated one or more categories, by the automated sorting system;
• feeding a first end of the strip of wood into a helix dryer pre-heated to 60 to 300 degrees Celsius;
• and
• drying the strip of wood at least partially, by dragging the strip of wood at least partially along a tubular spring forming means of the helix dryer.