Abstract: In one general aspect, various embodiments of the present invention can include a motorized surgical cutting and fastening instrument having a drive shaft, a motor selectively engageable with the drive shaft, and a manual return mechanism configured to operably disengage the motor from the drive shaft and retract the drive shaft. In at least one embodiment, a surgeon, or other operator of the surgical instrument, can utilize the manual return mechanism to retract the drive shaft after it has been advanced, especially when the motor, or a power source supplying the motor, has failed or is otherwise unable to provide a force sufficient to retract the drive shaft.

Abstract: A tissue thickness compensator may generally comprise a compressible core comprising a plurality of movable particles, and a wrap surrounding the compressible core. The plurality of movable particles may comprise at least one medicament. A tissue thickness compensator may generally comprise a compressible core comprising a plurality of crushable particles, and a wrap surrounding the compressible core. The plurality of crushable particles may comprise at least one medicament. The compressible core may comprise a material selected from a group consisting of a biocompatible material. The wrap may comprise a material selected from a group consisting of a biocompatible material. Articles of manufacture comprising the tissue thickness compensator and methods of making and using the tissue thickness compensator are also described.

Abstract: Surgical methods involving cutting and sealing tissue include affixing a first adjunct material to tissue at a treatment site, such as by stapling the adjunct to tissue. A second adjunct material is applied to at least a portion of the first adjunct material such that the second adjunct material interacts with the first adjunct material to form a seal in an area of the tissue covered by at least one of the first and the second adjunct material. The resulting tissue sealing structure, which includes a combination of the two adjuncts, is believed to be superior to the sealing properties of either adjunct alone.

Abstract: An acoustic wave resonator device includes two pairs of coupled spaced apart reflectors which define two resonant cavities. The two cavities are each provided with two interdigital transducers which provide intercavity coupling. Additional reactance coupling between the transducers in one cavity combines with the equivalent cavity reactance to provide series or parallel resonance at a selected pole frequency.

Abstract: A surface acoustic wave band-pass filter comprising a piezoelectric substrate having on one surface first and second SAW resonators tuned to the same frequency and coupled together. An input transducer is coupled to the first resonator and an output transducer is coupled to the second resonator. Each resonator is preferably formed by two spaced apart aligned grating reflectors and the two resonators are preferably coupled by an array of discrete parallel metallic strips extending between the two cavity resonators.

Abstract: A self-propelled rotary lawn mower. The drive shaft of the engine is operably connected through a clutch mechanism to the cutting blade and to a belt drive connected the front wheels to drive the mower across the terrain. By disengaging the clutch through manual action of a cable, the driving connection to both the blade and the wheels is stopped, so that the blade will not rotate when the mower is stationary. The housing of the mower includes inner and outer housing sections with the space between the housing sections defining a chamber. The exhaust gases from the engine are directed into the chamber and are discharged from the chamber adjacent the grass discharge outlet in the housing. Directing the exhaust gases through the internal housing chamber substantially decreases the noise level of the mower. The four wheels of the mower are adapted to be raised and lowered in unison by single lever control to thereby vary the height of the blade above the ground.