Fastening assembly for securing floor mat to carpet

A fastening assembly for securing a floor mat to a carpet, comprising:

• a first fastener that attaches to the peripheral portion of an attachment hole in the carpet, the first fastener defining an axial through hole;
• a knob assembly that attaches to the first fastener by insertion thereof into the through hole in the first fastener;
• and
• a second fastener that attaches to the peripheral portion of an attachment hole in the floor mat, the second fastener defining a second axial through-hole;
• wherein:
• the knob assembly comprises a knob base, inserted into the through hole of the first fastener, and a knob coupled to the knob base, the knob having a knob shank;
• the knob base is formed as a tubular body inserted into the through hole of the first fastener, having a knob acceptance hole in its center for accepting the knob, in which is formed, on the outside surface of the portion inserted into the through hole of the first fastener, a base flange that abuts the peripheral portion of the through hole of the first fastener and base latching pawls for latching with a latching part formed in the inner wall of the through hole of the first fastener;
• the knob and knob base are formed so that when the knob is inserted into the knob base, the knob is coupled to the knob base to be able to turn about its axis inside the knob base;
• the knob comprises a knob head for abutting against the peripheral portion of the through hole in the second fastener and latching means that are inserted into the knob base for latching to the knob base;
• the knob shank is shaped so that when turned through a prescribed angle about the axis of the knob shank inside the knob base, the base latching pawls are prevented from toppling inward and is configured to be able to turn about its axis to between an unlocked position, in which the inward toppling is not prevented, and a locked position, in which the inward toppling is prevented;
• and
• in a state in which the first fastener is attached to the carpet, the second fastener is attached to the floor mat, the knob assembly is coupled to the first fastener so as not to turn about the axis of the knob shank, and the knob head of the knob passes through the through hole of the second fastener, the second fastener of the floor mat is superimposed on the first fastener of the carpet, and, in a state in which the knob has been turned about its axis from the unlocked position to the locked position, the knob head abuts a latching part formed in the second fastener and pushes the second fastener in the axial direction against the first fastener, whereby the engagement between the base latching pawls of the knob base and the latching part of the first fastener is locked, and the floor mat is secured to the carpet.