Device for the removable fastening of a plate-shaped component onto a base with a T-groove open towards the component

A device for removably fastening a plate-shaped component onto a base, said plate-shaped component including a diametrically widened hole, said base including a T-groove having diametrically opposed shoulders, each of said shoulders having an edge, said device comprising:

• a substantially pot-shaped receiving element, said receiving element having a floor therein, said floor having a central hole therethrough, said receiving element further having a pair of snap wedges protruding axially therefrom on diametrical sides of said hole for being snappingly inserted into said diametrically widened hole in said plate-shaped component, thereby holding said receiving element onto said plate-shaped component;
• a head-bolt reciprocally guided in said central hole of said floor of said receiving element, said head-bolt having a first end and a second end, said head-bolt having a head at said first end thereof;
• biasing means inserted in said receiving element between said head of said head-bolt and said floor of said receiving element for biasing said head-bolt in a direction axially away from said floor of said receiving element;
• a cross-bar located at said second end of said head-bolt, said cross-bar being insertable in said T-groove of said base when said plate-shaped component is placed against said base, said cross-bar further having attached at one end thereof away from said head-bolt two radial extensions;
• means for axial and radial guidance of said cross-bar in response to rotation of said head-bolt, comprising:
• a first pair of diametrically opposed quarter circle segments attached axially to said cross-bar, said first pair of quarter circle segments having a first bevelled end;
• a second pair of diametrically opposed quarter circle segments attached axially to said receiving element at an angle of 90.degree. to said pair of snap wedges, said second pair of quarter circle segments having a second bevelled end, said first bevelled end and said second bevelled end being in mutual contact so that as said head-bolt is rotated from a locked position to an unlocked position said cross-bar is caused to likewise rotate and simultaneously axially move relative to said T-shaped groove, wherein said two radial extensions of said cross-bar are axially lifted off said shoulders of said T-groove thereby unlocking said plate-shaped component from said base when said head-bolt has been rotated from the locked to the unlocked position;
• and
• stop means for preventing said head-bolt from turning further than said locked position, said stop means comprising:
• at least one stop surface on said cross-bar which interferingly contacts said edge of at least one of said shoulders of said T-groove adjacent said cross-bar when said head-bolt is rotated to said locked position.

A fastening system comprising:

• a plate-shaped component having a diametrically widened hole;
• a base having a T-groove, said T-groove having diametrically opposed shoulders, each of said shoulders having an edge;
• a substantially pot-shaped receiving element, said receiving element having a floor therein, said floor having a central hole therethrough, said receiving element further having a pair of snap wedges protruding axially therefrom on diametrical sides of said central hole for being snappingly inserted into said diametrically widened hole in said plate-shaped component, thereby holding said receiving element onto said plate-shaped component;
• a head-bolt reciprocally guided in said central hole of said floor of said receiving element, said head-bolt having a first end and a second end, said head-bolt having a head at said first end thereof;
• biasing means inserted in said receiving element between said head of said head-bolt and said floor of said receiving element for biasing said head-bolt in a direction axially away from said floor of said receiving element;
• a cross-bar located at said second end of said head-bolt, said cross-bar being insertable in said T-groove of said base when said plate-shaped component is placed against said base, said cross-bar further having at least one radial extension thereon, said at least one radial extension of said cross-bar interferingly engaging said shoulders of said T-groove thereby locking said plate-shaped component onto said base when said head-bolt has been depressed against said biasing means and rotated from an unlocked position to a locked position;
• stop means for preventing said head-bolt from turning further than said locked position;
• and
• means for axial and radial guidance of said cross-bar in response to rotation of said head-bolt, so that said at least one radial extension of said cross-bar is axially lifted off said shoulders of said T-groove when turning said head-bolt from the locked position to the unlocked position.