Patent ID: 7549361
Filing Date: 2009-06-23
Classification: B26D,B26F,F16F,Y10T

Abstract:
1. A vibration damping apparatus for reciprocating drive, for damping vibration occurring upon conversion of rotary motion, from a rotation outputting shaft of a rotation drive source, to reciprocal motion in a reciprocating drive direction, comprising: a first conversion mechanism, the first conversion mechanism including a first rotary shaft, a first counterweight contacting the first rotary shaft, and a first drive shaft contacting the first counterweight the first drive shaft being connected to the first counter weight at a first drive position, the first drive position being eccentric with respect to the first rotary shaft, to convert a rotary motion of the first rotary shaft to reciprocal motion, via the first drive shaft at the first drive position, in the direction of the reciprocating drive direction, wherein the first counter weight has a center of gravity in a position on a side symmetric with the first drive position with respect to the first rotary shaft, for balancing an offset load occurring upon motion conversion; a second conversion mechanism, the second conversion mechanism including a second rotary shaft, a second counterweight contacting to the second rotary shaft, and a second drive shaft contacting the second counterweight, the second drive shaft being connected to the second counter weight at a second drive position, the second drive position being eccentric with respect to the second rotary shaft, to convert a rotary motion of the second rotary shaft to reciprocal motion, via the second drive shaft at the second drive position, in the direction of the reciprocating drive direction, the second conversion mechanism being provided in pair with the first conversion mechanism so as not to be in direct contact with the first conversion mechanism and arranged symmetric with the first conversion mechanism with respect to a reference virtual plane parallel with the reciprocating drive direction and the second rotary shaft rotating at equal speed reverse to and parallel with the first rotary shaft so that a reciprocal motion in the reciprocating drive direction is included in the second drive position synchronously with a reciprocal motion converted by the first conversion mechanism, wherein the second counter weight provided in pair with the first counter weight has a center of gravity in a position on a side symmetric with the second drive position with respect to the second rotary shaft, for balancing an offset load occurring upon motion conversion; and a combining mechanism to extract and combine reciprocal motions in the reciprocating drive direction which is converted from rotary motions by the first conversion mechanism and the second conversion mechanism, respectively, rotary driving force from the rotation drive source being transmitted via a belt to the first conversion mechanism and the second conversion mechanism.