Sliding drawer suspension

A three-part sliding drawer suspension comprising outer, intermediate and inner channel section rails each having channel sides and a channel bottom, the intermediate rail being nested in a retracted position between the channel sides of the outer rail and having its channel opening facing away from the channel opening of the outer rail, the inner rail being nested in a retracted position between the channel sides of the intermediate rail and having its channel opening facing toward the channel opening of the inner rail, outer and inner ball bearings each having a channel-section ball bearing cage having channel sides and a channel bottom between the outer and intermediate rails and between the intermediate and inner rails, respectively;

• extension of the intermediate rail relative to the outer rail being limited by engagement of a rear end surface of the channel bottom of the outer cage with a rear tab bent inwardly from the rear end of the channel bottom of the intermediate rail and simultaneously therewith engagement of front end surfaces of the channel sides of the outer cage with a pair of spaced-apart front tabs each bent inwardly from the front end of the outer rail;
• said retracted position of the intermediate rail relative to the outer rail being defined by engagement of said rear tab on the intermediate rail with a rear tab bent inwardly from the rear end of the channel bottom of the outer rail;
• extension of the inner rail relative to the intermediate rail being limited by simultaneous engagement of rear and front end surfaces of the channel bottom of the inner cage with a tab bent inwardly from the rear end of the channel bottom of the inner rail and with a front tab bent inwardly from the front end of the channel bottom of the intermediate rail, respectively;
• said retracted position of the inner rail relative to the intermediate rail being defined by engagement of said front tab on the intermediate rail with a front tab bent inwardly from the front end of the channel bottom of the inner rail;
• said inner and outer cages normally being positioned so that the end surfaces of each cage are spaced at equal distances from the tabs with which they engage;
• a first abutment member comprising a pair of tabs each bent inwardly from a channel side of the outer rail at a point intermediate the front and rear tabs on the outer rail and a second abutment member comprising a tab bent inwardly from the channel bottom of the intermediate rail at a point intermediate the front and rear tabs on the intermediate rail, for engaging rear end surfaces of the channel sides and a front end surface of the channel bottom of the outer cage, respectively, said first and second abutment members being positioned to provide a small clearance between them and said rear end and front end surfaces of the outer cage, respectively, when in said normal position and with the intermediate rail in its retracted position, whereby said first and second abutment members engage said end surfaces of the outer cage when displaced from its normal position and shift the outer cage to its normal position on closing movement of the suspension;
• said tab constituting the second abutment member being positioned to pass freely through the spacing between said spaced-apart front tabs on the front end of the outer rail;
• and a third abutment member comprising a pair of tabs bent outwardly from the channel sides of the inner rail at a point intermediate the front and rear tabs on the inner rail for engaging front end surfaces of the channel sides of the outer cage, and positioned to provide a small clearance between the third abutment member and said front end surfaces of the inner cage when in its normal position with the inner rail in its retracted position, whereby said third abutment member engages said front end surfaces of the inner cage when displaced forwardly from its normal position and shifts it to its normal position on closing movement of the suspension.