Patent · US Expired

Extendible tree trimming apparatus

US4991298A · kind A · utility

58Cited by
19References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 13, 1988
Grant dateFeb 12, 1991
Priority date
Expiry dateSep 13, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB27B19/09
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

An extendible tree trimmer includes an extendible tube unit with a motor and a cutting blade connected to the opposite ends. The tube unit includes a first housing and a telescopic second housing connected by a releasable coupling unit. A first shaft connected to the motor extends through the first housing and second shaft is telescoped with the first shaft and extends through the second housing to the cutting blade. The housings are releasably coupled for telescoped positioning. A rotary bearing supports the shafts in the housings. A gear reduction unit and a slip clutch unit connects the motor to the first shaft. The cutter head includes a rotating cam secured to the second shaft. The cam has a peripheral groove with axially offset portions and with a follower in said groove. The follower is secured to the blade which reciprocates in the plane of the blade. The blade has teeth on the opposed edges to cut with the blade moving toward the housing. The face of the cutter support is S-shaped with a concave upper wall and a convex lower wall for engaging a limb. The bearing includes an inner race having a hexagonal cross-section in sliding coupling to the first shaft of corresponding …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.