US2663506A

US2663506A - Wood chipper

Info

Publication number: US2663506A
Application number: US261216A
Authority: US
Inventors: Vaughan William Kent
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-12-12
Filing date: 1951-12-12
Publication date: 1953-12-22
Anticipated expiration: 1970-12-22

Description

2 Sheets-Sheet l Dec. ZZ, 1953 W. K. VAUGHAN WOOD CHIPPER File-d Deo. l2, 1951 Dec. 22, 1953 w. K. VAUGHAN 2,663,505

woon CHIPPER Filed Dec. l2, 1951 v 2 Sheets-Sheet 2 4 www Patented Dec. 22, 1953 TED TENT OFFICE 5 Claims.

This invention relates to wood chippers of the type which are used industrially for the purpose of cutting Wood into small pieces or chips of suit able size preparatory to the manufacture of wood pulp for use in the production of paper, paper board and the like. The invention relates particularly to the mounting of the knives on the chipper disc.

Wood chippers usually comprise a rotatable disc having a series of knives er blades which eX tend at a suitable cutting angle a short distance above the surface of the disc and which are usually spaced symmetrically around the working face of the disc radially or tangentially of the disc hub. Usually, a plurality of knives or blades are mounted on the disc and heretofore it was thought important advantages were gained bv spacing the knives such that two or more kn s were in engagement with the log at one time. The log to be chipped usually is fed to the disc through an inclined feed spout or chute which brings the end of the log against the surface oi the where it is engaged by the knives or blades.

Heretofore, the knives or blades have been mounted with the cutting' edges adjacent to slots which extend through the disc and through which the chips are discharged as they are cut from the log. This conventional arrangement of knife or blade mounting and slots has several inrportant disadvantages.

The trend over recent years has been to de sign the dise and the arrangement of the knives such that the end of the log is engaged by two or more knives or blades at one time. This is accomplished by mounting a plurality of knives on the disc and by spacing the knives as closely as possible. As the disc structur is progressively weakened as the spacing between the knife slots is decreased, particularly adjacent to the hub, and, accordingly, the number of knives which can be mounted on the disc is restricted. Also, the knives must be spaced a substantial distance from the hub of the disc to avoid weakening the disc, and this has the disadvantage that only relatively large diameter logs can be engaged simultaneously by two or more knives and small logs are engaged only by a single knife with attendant variations in chip sizes andinereasedproduction of sawdust and bruised chips. A further disadvantage is that it is necessary to provide, at the discharge side oi each slot a device known as a card breaker to break the oversize chips or cards as they pass through the slots into chips of a desired uniform size suitable for the sub- (Cl. Zal-278) sequent cooking operation to form wood pulp. Also, the chips as they pass through the slots, lose their momentum and it may be necessary to provide a blower attachment, such as a vane, on the outside of the chipper disc, to blow the chips clear of the slots. Chips tend to get caught by this vane attachment with attendant increase in the production of bruised chips and fines.

An important object of this invention is to' provide a knife mounting for a chipper disc which is mounted on the surface of the disc and with which the conventional knife slots are eliminated.

A further important object of this invention is to provide a knife mounting for wood chippers in which the knives or blades can be extended to a point adjacent to the hub of the chipper disc without weakening the chipper disc.

A further important object oi the invention is to provide a knife mounting for wood chippers in which the chips are broken into a substantially uniform size as they are cut from the log and are delivered to and discharged from the periphery of the knife mounting assembly.

A further object of the invention is to prom vide a knife mounting for wood chippers which permits the arrangement of the chipper disc and the flywheel and/or the driving pulley as an integral unit to provide a compact and sturdy design.

A still further object of the invention is to provide a chipper disc in which the rate at which each knife blade engages the end of the log is such that the log does not have an opportunity to rebound from the face of the disc at the end of the engagement of one knife before it is engaged by the next following knife.

An understanding of the manner in which the above and other objects of this invention are attained may be had from the following description, reference being made to the accompanying drawing, in which;

Figure l is a side elevation oi a wood chipper incorporating the improvements or the present invention;

Figure 2 is a front elevation;

Figure 3 is an enlarged detail view; and

Figures 4 and 5 are detail views.

Like reference characters refer to like parts throughout the specification and drawings.

Referring to the drawings, the numeral iii in dicates a chipper disc enclosed, during operation, by a removable cover i l. The disc, usually, is in the form of a heavy casting. The disc is mounted on a shaft 2 and is driven from a motor, not shown, through a driving pulley lia.

edge thereof extending at an angle to the outer surface of said support, means extending rearwardly of each knife blade support towards but stopping short of the cutting edge of the next following knife blade, and a passageway for wood chips defined by said last mentioned means, the opposing surface of the disc and opposing faces of adjacent knife blade supports, said passageway extending from end to end of said knife blade supports.

2. In combination with a wood chipper comprising a rotatable disc, a plurality of pairs of clamping members mounted on and secured to a surface of said disc and symmetrically arranged thereon in a generally straight line extending from a point adjacent to the hub of the disc towards the periphery thereof and extending beyond the surface of the disc, a knife blade secured between each pair of clamping members with a cutting edge extending at an angle to the outer surface of the clamping member, means extending rearwardly of each knife blade support towards but stopping short of the cutting edge of the next following knife blade, and a passageway for wood chips defined by said last mentioned means, the opposing surface of the disc and opposing faces of adjacent knife blade supports, Said passageway extending from end to end of said knife blade supports.

3. In combination with a. wood chipper comprising a rotatable disc, a plurality of knife supports mounted on and secured to a surface of said disc and symmetrically arranged thereon in a generally straight line extending from a point adjacent to the hub of the disc towards the periphery thereof and extending beyond the surface of the disc, each of said supporting means comprising a pair of members adapted to be clamped together to form a seat for the rearward 6 edge of a knife blade and having opposing faces adapted to engage the rearward portion of the knife blade and support it with a cutting edge thereof extending at an angle to the outer surface of the support, log supporting means extending rearwardly of each knife blade support towards but stopping short of the cutting edge of the next following knife blade, and a passageway for wood chips defined by the log supporting means, the opposing surface of the disc and opposing faces of adjacent knife blade supports, said passageway extending from end to end of said knife blade supports.

4. A wood chipper according to claim 3 in which the face of the knife blade supporting member below the leading edge of the knife blade is arcuately curved from the knife blade to the surface of the disc.

5. A Wood chipper according to claim 3 in which the log supporting means is in the form of a removable plate carried by the knife blade supporting member and extending rearwardly thereof towards but stopping short of the cutting edge of the next following knife blade.

WILLIAM KENT VAUGHAN.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,955,640 Knowles Apr. 17, 1934 2,247,665 Ottersland July 1, 1941 2,312,612 Wetmore Mar. 2, 1943 2,337,407 Ottersland Dec. 21, 1943 FOREIGN PATENTS Number Country Date 45,150 Sweden Mar. 12, 1919 509,844 Germany Oct. 13, 1930