Modular system for assembling a motorized adjustable support apparatus for the upholstery of furniture for sitting and/or lying

Modular system for assembling a motorized adjustable support apparatus for the upholstery of a piece of furniture for one of sitting and lying, comprising:

• a) a first support element including a first longitudinal rail assembly;
• b) a second support element including a second longitudinal rail assembly;
• c) said first and second longitudinal rail assemblies being detachably connected by a connecting element to form a base of the support apparatus, in use;
• d) in an assembled state the adjustable support apparatus includes the two support elements adjustable relative to one another for supporting the upholstery;
• e) at least one connecting shaft being provided for transmitting the rotation of a first pivot shaft connected to the first longitudinal rail assembly to a third pivot shaft connected to the second longitudinal rail assembly;
• and
• f) ends of the at least one connecting shaft being detachably insertable into recesses defined in the first and third pivot shafts, and being securable against rotation with respect to the first and third pivot shafts.