Cam actuated tree cutting shears and buncher

• US 4,050,488 A
• Filed: 04/23/1976
• Issued: 09/27/1977
• Est. Priority Date: 04/23/1976
• Status: Expired due to Term

• Current Assignee: Alva Z. Albright
• Original Assignee: Alva Z. Albright
• Inventors: Albright, Alva Z.
• Primary Examiner(s): Simpson, Othell M.
• Assistant Examiner(s): Bray, W. D.
• Application Number:
  US05/679,524
• Time in Patent Office: 522 Days
• Field of Search: 37/2 R, 144/3 D, 144/34 B, 144/34 E, 144/309 AC, 83/928, 83/693
• US Class Current: 144/339
• CPC Class Codes: A01G 23/081 Feller-bunchers, i.e. with bunching by felling head A01G23/083 takes precedence

Abstract

Shear knives are pivoted, side by side with sharp edges opposed, by a pair of adjacent ends to a pivot strap. Cam rollers are mounted respectively for rotation on the knives at the junctions of their free ends and outboard sides. Rearwardly converging cam edges are mounted in forwardly extending arms of a forwardly movable frame, and arms being adapted to receive the pivot strap transversely therebetween and a tree of not over an equal diameter. The knives are slidably mounted in slots in the respective arms with their free ends forward and their roller cam followers respectively engaging the converging cam edges on which they are spring biased forwardly. The knives are cammed closed to cut a tree as the movable frame moves forwardly relative to tree and knives. A swinging member, having a transverse blade pivoted to the top thereof, is itself pivoted to one of the pair of arms and is hydraulically actuated to swing past a cut tree between the arms and back to raise the tree clear of the shear knives and onto a raised floor rearwardly and hold it there. A second pair of arms vertically spaced above the first pair also receives the tree which is releasably retained therebetween by a one-way pair of gates at the ends thereof.

Claims

1. Cam actuated tree cutting shears for continuously and automatically shearing and accumulating trees for bunching, in combination with a power train having an auxilliary hydraulic power system and a forward lift, comprising:

a. frame means having rear connections connecting it to said forward lift for moving and tilting said frame means for bunching, said frame means also having forwardly extending upper and lower pairs of arm means for receiving trees therebetween, and having raised floor means positioned rearwardly and between said lower pair of arm means;

b. openable and closable shear means mounted for forward and rearward motion in and between said lower pair of arm means;

c. camming means mounted rigidly in said lower pair of arms and a rotatably mounted follower means on said shear means for opening said shear means in said forward movement and closing said shear means in said rearward movement; and

d. hydraulically operable tree accumulating means for automatically engaging and lifting cut trees off said shear means and onto said raised floor means and for storing said cut trees thereon and between said upper pair of arms means.

2. Cam actuated tree cutting shears as described in claim 1 wherein said openable and closable shear means comprises:

a. a transverse pivot strap with oppositely disposed ends for mounting transversely between said lower pair of arm means;

b. a pair of elongated knives, each having sharp edges disposed thereon, said knives being pivoted by respective ends, with said sharp edges being opposed, to oppositely disposed ends of said pivot strap.

3. Cam operated tree cutting shears as described in claim 1 wherein said camming means comprises:

a. a double cam defining rearwardly converging cam edges mounted respectively in said lower pair of arm means; and

b. a pair of roller cam followers, each respectively mounted on free ends of said shear means for rollably engaging said cam edges respectively.

4. Cam operated tree cutting shears as described in claim 1 wherein said hydraulically operable tree accumulating means comprise:

a. a swinging member pivoted adjacent said raised floor means to an arm of said lower pair of arm means, said member being adapted to swing from a vertical position forward and downward to a horizontal position;

b. a blade, having a sharp edge, pivoted to a free end of said swinging member with said sharp edge extending rearwardly and transversely between said lower pair of arm means, said blade being adapted to pivot rearwardly when swung forwardly and downwardly past a cut tree and to engage said tree with its sharp edge when swung rearwardly and upwardly;

c. an hydraulic cylinder pivoted by its cylinder end adjacent said swinging member and with its rod end pivoted to the top of said swinging member below said pivoted blade, and adapted to pivot said swinging member between vertical and horizontal positions;

d. a pair of gates pivoted to the ends of said upper pair of arm means adapted to swing inward only against an outward bias;

e. a pair of hydraulic cylinders pivoted between respective arms of said upper pair of arm means and said gates for overriding said bias to open said gates for releasing accumulated trees for bunching; and

f. hydraulic conduits and control valves mounted in said frame means for connecting said cylinders to said auxilliary hydraulic power system of said power train and for initiating the action of said cylinders by the operation of said cam operated shears.

5. Method of shearing and accumulating trees comprising the steps of:

a. slidably mounting shears in a frame, said frame having a forward open end and a rearward end, said shears having pivoted ends disposed rearwardly in said frame and free ends disposed forwardly in said frame;

b. camming said shears closed by the cooperation of converging cams mounted rigidly in said frame engaging cam followers mounted onn the free ends of said shears;

c. actuating said camming of said shears by introducing a tree end between said open end of said frame and by advancing said frame forwardly;

d. raising said cut tree clear of said shears and accumulating them in said frame;

e. spring biasing said shears forwardly and open for engaging another tree therebetween; and

f. bunching said cut and accumulated trees by tilting said frame forward.