GB1203414A - Doffer comb drive for cards or similar machines - Google Patents

Abstract

1,203,414. Doffing comb for carding engine. DEUTSCHER SPINNEREIMASCHINENBAU INGOLSTADT NIEDERLASSUNG DER SCHUBERT & SALZER MASCHINENTABRIK A.G. 5 Oct., 1967 [25 Oct., 1966], No. 47822/66. Heading D1N. To overcome or at least diminish undesired vibrations, a doffer comb device consists of an oscillatory two-or-more mass system of which an end mass is a carrier of the doffer comb and together with a spring member, which connects this end mass with an adjacent mass which may be an excitation mass, forms an oscillation compensator whose natural frequency is tuned to the excitation frequency of the excitation mass. When the excitation frequency coincides with the natural frequency of the oscillation compensator, the excitation mass becomes non-oscillating and the compensator mass carries out an oscillation superimposed on the basic swing. The doffer comb may carry out linear or arcuate oscillations. The excitation may be produced through mechanical, electromagnetic or hydraulic means. In Figure 4, the comb carrier 1, the cross pieces 2 and the comb 3 together represent the compensating mass, and the torsion rod 4 represents the spring member. The excitation mass consists of the reinforced end 5 of bar 4, torque tube 6, clamping ring 7, fly wheel 8, rotating shaft 9, bracket 10, roller bearings 11 and 12, coupling 13, crankshaft 14, balance weights 15 and 16 and fly wheel with pulley 8. By means of motor 22 the tube 6 and thus the entire device maintains a periodic basic swing, the periodically altering inertia forces of the drive acting as excitation forces on the excitation mass. The doffer device may carry a sensing element (e.g. an electromagnetic pick up) sensing the compensating mass oscillations, whereby the compensating frequency sensed serves through an amplifier as an excitation frequency to the drive. To prevent an undesired resonance point being passed through on starting and stopping the device, a supplementary oscillatory mass can be directly coupled with the excitation mass through a spring member, the excitation mass being adjacent to the compensating mass.