Patent GB-1331502-A (GB)
Title: Device for driving pins or similar members
IPC: B25C1/14
Filed: 1970-11-04
Abstract: 1331502 Cartridge actuated pin driving tool P TERMET 4 Nov 1970 [5 Nov 1969] 52417/70 Heading B4C A cartridge actuated device for driving pins or the like, comprises a driving plunger assembly displaceable within a barrel to drive a pin or the like inserted in the barrel, and is characterized in that the assembly comprises at least two separate parts, each part being provided with an abutment surface, intended to abut against a corresponding surface of the device only when overtravel of the assembly occurs. The corresponding surfaces are arranged so as to assure the successive stoppage of the two or at least two separate parts of the assembly. In the device of Fig. 1 the radially projecting wings 11 of the forward part 9 slide in grooves 12. In use the plunger assembly will drive a pin 2 into receiving material 3. Should the assembly "over-travel" the rear part 6 will first be arrested by abutment between surface 8 and abutment surface 4 and subsequently the forward part 9 is arrested by engagement of the forward edges of the wings 11 with surfaces 14. The wings may be tapered in the forward direction and the grooves 12 may be similarly shaped. The wings 11 may be of helical form (Fig. 17, not shown) and may be located in helical grooves in the barrel so that upon forward motion of the plunger assembly, the forward part will rotate. The forward end of part 9 is knurled so as to create a greater frictional contact with a pin. In the embodiment illustrated in Figs. 6 and 10, the wings 11 are separate from and are slidable axially of the barrel relative to the forward part 9. When overtravel occurs, the rear part 6 is first arrested by surfaces 8, 4 abutting. The wings 11 are then arrested by forward ends of grooves 12 and finally the forward part 9 is arrested when surface 19 contacts the bosses 20 of the wings. In a first modification of Figs. 6 and 10 (Fig. 14, not shown) the surface 4 is provided on a ferrule which is movable axially relative to the remainder of the barrel and which includes three rearwardly and axially extending teeth engaging in three axial grooves in the barrel. The grooves 12 are aligned with grooves in the ferrule. On overtravel of the plunger assembly the surface 8 initially engages surface 4 so that the ferrule is moved forwardly until a shoulder (25) engages an abutment (24) in the barrel. The wings 11 and forward part 9 thereafter move forwardly together until the wings engage a shoulder (35). The forward part is subsequently arrested by surface 19 engaging the rear of bosses 20. In a second modification of Figs. 6 and 10 an intermediate part (36) (Fig. 18, not shown) is positioned between the rear part 6 and the forward part 9. When the assembly overtravels wings (37) on the intermediate part will, upon the wings 11 being arrested, impart a force thereto thus causing bosses 20 to grip the forward part. In a further modified arrangement-of Figs. 6 and 10 the forward part has helical grooves (38) (Figs. 20-22, not shown) in which bosses 20 on the wings engage so that when the forward part moves axially relatively to the wings a rotary motion will be applied thereto until stops at the ends of the grooves abut the bosses. The plunger assembly may comprise two winged parts (39, 40). (Fig. 23, not shown), the wings of one part moving in the same grooves as the wings of the other part. The rear part (39) is, upon overtravel, first arrested and the forward part 40 continues its forward movement until arrested. In a modified arrangement the wings of one part are located in grooves disposed at right angles to the grooves for the wings of the other part. In the embodiment of Fig. 27 the plunger assembly comprises two parts 51, 52. The rear part has a surface 51b which engages, upon overtravel, with surface 53, and the forward part has a surface 52b which engages with a surface 54. In a modified arrangement (Fig. 28) on overtravel the rear part is arrested by a projection 57 and the forward part 56 is provided with means (not shown) for preventing rotation and with a groove 58 so that the head of the forward part can pass the projection 57.