Fingerprinting arrangement

Claim 1

An improved fingerprint developing arrangement for providing a visually detectable fingerprint image on a pre-selected surface having a fingerprint thereon, comprising, in combination: a frame means; a drum means movably mounted on said frame means and having peripheral walls defining a powder containing cavity, and said peripheral walls having a first portion defining an aperture therethrough providing communicatioN with said powder containing cavity; fingerprint powder in said powder containing cavity; closure means coupled to said peripheral walls of said drum means adjacent said aperture and movable thereon from an open position allowing access to said aperture to a closed position removably clamping the pre-selected surface having the fingerprint thereon over said aperture in powder sealing relationship to said first portion of said peripheral walls; latch means coupled to said drum means for detachably clamping said closure means in said closed position to prevent said fingerprint powder from leaving said powder containing cavity for the condition of said closure means in said closed position thereof, said latch means comprising: a spring loaded hinge means for coupling said closure means to said drum means, and said spring loaded hinge means resiliently biasing said closure means into said closed position thereof; motion producing means for moving said drum means to provide contact between the pre-selected surface in said aperture and said fingerprint powder in said powder containing cavity, said motion producing means comprising: a rotation producing means for rotating said drum means in a preselected arc of rotation about a pre-determined axis, and said fingerprint powder contacting the preselected surface in said aperture at least once during each movement in said preselected arc of rotation thereof; said drum means rotatably mounted on said frame means; interlock means operatively connected between said frame means and said drum means for preventing said closure means from moving from said closed position to said open position thereof for a predetermined portion of said preselected arc of rotation of said drum means; vibration producing means for inducing a vibration of said drum means to jar said fingerprint powder loose from regions adjacent said first portion of said peripheral walls, said vibration inducing means comprising: a pluraility of protuberances coupled to said frame means in a preselected spaced relationship thereon adjacent said drum means: a striker bar means mounted on said drum means in protuberance engaging relationship to said plurality of protuberances for sticking said protuberances and vibrating said drum means during predesigned portions of said pre-selected arc of rotation of said drum means.