Abstract: There is provided an injection needle removing apparatus for dental cartridge syringe comprising a chuck device (22) mounted within a housing (11) and including chuck jaws (26) for gripping a needle hub (25?), means for opening and closing the chuck jaws, a needle receptacle (14) adapted to rotatably support the housing (11), and means (50, 55, 56) for rotating the housing relative to the receptacle, the rotation of the housing causing the chuck device, together with the housing, to be rotated relative to the injection needle, thereby removing the injection needle from the syringe. In this arrangement, any rotative power transmission mechanism is not required to rotate the chuck device itself relative to the syringe.

Abstract: An electrically-driven dental injector used in orally injecting such an injection liquid as an anesthetic in dental treatment. Electrically-driven dental injectors includes one having a mechanism for disengaging a pinion (82) from a rack (48) in order to retract a plunger rod (44) upon completion of injection; however, it has heretofore been necessary to manually operate the operating part from outside each time. The inventive electrically-driven dental injector is so arranged that the plunger rod can be manually pushed back directly oupon completion of injection without requiring manual operation, and, to this end, the injector comprises a latch mechanism (84) for engaging/disengaging the ring gear (70) of a planetary reduction gear (50) with/from a casing (52), and an operating rod (94) extending through a support member (20) and functionally cooperating with the latch mechanism (84).

Abstract: A riveting motor tool for use in fastening a pop rivet in which a fastening shank of the rivet having an enlarged end is inserted into a flanged sleeve body and the fastening shank is grasped to be torn off for forming a splayed portion at a free end of the sleeve. The tool grasps the fastening shank and is withdrawn by a slide shaft that is reciprocated by a rotary drive. Springs urge the shaft in the opposite direction. The rotary drive has teeth spaced apart from each other a distance greater than the stroke of the shaft, that engage with a lug on the shaft having arcuate recesses on each side of the lug for reception of the teeth, the rotary drive being reversible to engage the lug from either side. The shaft is hollow and torn off portions of the shank move lengthwise through the shaft out the rear end of the shaft which is disposed in a receptacle for receiving and retaining these torn off portions.