Abstract: A door lock set includes: a housing fixed on a door; an upper cam rotatably mounted on an upper portion of the housing and operatively retracting an upper latch; a lower cam rotatably mounted on a lower portion of the housing and operatively retracting a lower latch; a first linking rod and a second linking rod juxtapositionally pivotally secured between the upper cam and the lower cam and respectively disposed on a left side and a right side of the two cams; whereby upon a clockwise rotation of either cam, each latch provided on a right side of the door will be retracted; while upon a counterclockwise rotation of the cam, the latch provided on a left side of the door will be retracted, thereby optionally satisfying any door latch regardless of its right side position or left side position.

Abstract: A door lock set including: a housing fixed on a door; an upper cam rotatably mounted on an upper portion of the housing and operatively retracting an upper latch by a thumbturn knob; a lower cam rotatably mounted on a lower portion of the housing and operatively retracting a lower latch by rotating a door knob secured to a spindle of the lower cam; a linking device having an upper linking plate pivotally secured to the upper cam, a first linking rod and a second linking rod respectively upwardly pivotally secured to the upper linking plate and respectively downwardly pivotally secured to the lower cam, whereby the spindle can be rotated in a large angle for rotating the lower cam for retracting the lower latch and for synchronously biasing the upper cam for retracting the upper latch for opening the door, thereby being suitable for a door-knob type lock set; and the linking device may be optionally disposed on a right side portion of the upper cam for retracting the latch as provided on a right side of the do

Abstract: A door lock includes a driving cam secured to a first spindle operatively retracting a latch, a follower cam secured to a second spindle operatively retracting a dead bolt and a linking rod having a first pin formed on a rod end pivotally connected with a cam protrusion formed on the driving cam and having a second pin formed on the other rod end slidably moving in an arcuate slot in the follower cam, whereby upon a rotation of an inside knob for rotating the driving cam for retracting the latch, the linking rod will be biased to pull the follower cam for rotating the follower cam to retract the dead bolt for simultaneously retracting both the deadbolt and the latch for opening a door smoothly, quickly and safely.

Abstract: A door handle device includes: a restoring device mounted on a washer secured to a door, a spindle laterally adjustably mounted in the restoring device, and a lever handle having a handle sleeve fixed on an outer end portion of the spindle rotatably driving the spindle for operating a latch bolt for opening the door, in that the restoring device is provided for restoring the lever handle once depressed by a door opener and for adjustably securing the spindle on the device with respect to a door thickness in order for a connection of the spindle to a latch bolt mechanism operatively retracting or extending the latch bolt. The spindle is directly secured to the door handle so that a handle sleeve formed on a central portion of the door handle may be made as slim as possible.

Abstract: A tubular latch includes: a biasing lever pivotally mounted on a housing of the latch having an upper depression portion operatively pulled by a drag slide biased by a cam of a handle driving shaft, and having a lower forcing portion of the biasing lever operatively pulling a latch for opening the door, whereby upon a depression of a handle secured to the handle driving shaft at a small angle to pull the drag slide rearwardly to bias the upper depression portion of the lever about a lever pivot with a small stroke, the lower forcing portion below the upper depression portion will be biased with a greater stroke for fully retracting the latch for easily opening the door, without requiring a great rotating angle for depressing the handle.