| 摘要 |
<p>1,090,480. Portable power tools. ROCKWELL MANUFACTURING CO. Sept. 7, 1965 [Sept. 11, 1964], No. 38253/65. Heading B3N. A portable nut runner or screwdriver comprises a fluid operated reversing vane-type motor 30, Figs. 1 and 2, a planetary gearing unit 16, and a torque control clutch 18, which is adapted to stop the motor when a predetermined torque is reached. A push button valve 22 is located on housing 10 and operates as a servo-control valve for reversing the direction of rotation of the motor. At the rear end of motor 30 is a start valve 32 which is actuated by a rod 34 moved axially by clutch 18. Valve 32 may be replaced by a trigger operated valve inserted in an opening in place of a plug 35. Fluid is supplied to valve 22, at line pressure through a passage 50, a part 54, and a passage 56, Fig. 3. Valve chambers 64, 66. Figs. 4-6 have plungers 68, 70 slidable therein and the chambers are connected to the motor cylinder 40 by ports 89, 90 on opposite sides of rotor 42. Plungers 68, 70 are normally urged by springs 97 so as to close ports 89, 90, but when valve 22 is actuated, fluid is supplied to the chambers 64, 66 through openings 98 and 99. Valve 22 also supplies fluid to either passage 103 or passage 105 at the other end of the plungers, so that the pressures at both ends of one of the plungers are equalized, and the spring 97 of that plunger moves the latter to close its inlet port. In a modification, a straight power tool, Figs. 7-10 comprises an automatic start valve 144, a push button reversing valve 157, and valves 198 slidable in chambers 190. Fluid passes from chamber 150 to chamber 155 and into either passage 180 or 182 according to the position of valve 157. The corresponding valve 198 is actuated to thus open its inlet port 192 and the motor 185 is rotated. In the tool of Figs. 7-10 all of the high pressure fluid which rotates the motor flows through valve 157, whereas in the tool of Figs. 1 and 2 only a small portion of the fluid flows through valve 22.</p> |
