JPH02261601A - Circular sawing brade provided with saw-chain forming cutter - Google Patents

Abstract

PURPOSE: To obtain a rigid economic cutting blade supported onto a single disc by fixing a chain to a periphery of the disc in the state that an anchor is received by a tooth slot and a side link is crossed over sprocket teeth, thereby easily replacing the cutting chain. CONSTITUTION: The circular saw blade comprises a cutting chain 24 having a link including an anchor link 26 and a cutter link 32. Each anchor link has an anchor part 28 extended to one side of the chain. Opposed side links 30 couple the anchor link. A specific link of the links 30 is the link 32. A disc 12 having alternate sprocket teeth 16 and tooth slots 18 extended to a circumference is formed. The chain is fixed to a circumference of the disc for receiving the anchor part by the slot. The links 30 are held by laterally moving from the disc at the chain over the sprocket teeth. The disc 12 is formed of a single sheet material made of a material such as a steel or the like. Accordingly, its structure is easy and relatively light in weight.

Description

DETAILED DESCRIPTION OF THE INVENTION This application is a continuation-in-part of US patent application Ser. No. 07/149,398, filed February 28, 1988, and later abandoned.

INDUSTRIAL APPLICATION FIELD OF THE INVENTION The present invention relates, above, to circular cutting blades, and more particularly to circular cutting blades that use a chain with a cutter link to serve as a cutter for the blade.

Circular-sided blades of the type disclosed herein are used in conjunction with hand-held power saws, which are also used in conjunction with equipment for felling scrub and short-stem trees. The blade is mounted on a motor-driven arbor that rotates at a relatively high speed to cut the material, typically wood.

BACKGROUND OF THE INVENTION Many circular-sided blade assemblies using chain-shaped cutters are known. One such blade is disclosed in U.S. Pat. No. 4,627,322 to Hayhurst, Jr. This device uses a pair of discs that sandwich a portion of the saw chain around its periphery. Other blades use circular discs around which chainsaw-shaped cutter links are attached, such as with rivets or other fasteners that secure the links to the disc.

Although the blades described above are useful for certain purposes, each blade encounters difficulties when used with extremely large brush or hard materials. In the case of the first described blade, there is no device for engaging the drive link or anchor link on the saw chain, so that the chain section is free to rotate around the disc. If the chain loosens during use, there will be more slippage when driving the chain with the disc. In the case of a device with a chainsaw-type cutter mounted on a disc, the blade is used as a copse cutter, and in case of damage to one of the cutting teeth, which often occurs when hitting a rock instead of a tree, the cutting tooth must be removed and replaced individually.

The invention includes a cutting chain with links having an anchor link and a cutter link.

Each anchor link has an anchor portion extending to one side of the chain. Opposed side links connect the anchor links. Certain of the side links are cutter links. A disk is formed having alternating circumferentially extending sprocket teeth and tooth spaces. The chain is secured around the disc with the anchor portion received in the tooth groove. The side links of the chain straddle the sprocket teeth and hold the chain from moving laterally away from the disc.

SUMMARY OF THE INVENTION It is an object of the invention to provide a cutting blade in which a disc supporting the cutting chain and an anchor portion of the cutting chain are positively engaged.

More specifically, these anchor portions seat within tooth spaces provided in the disc.

Another object of the invention is to provide a cutting blade in which the side links of the cutting chain attach the chain across the sprocket teeth of the disc.

Yet another object of the invention is to provide a cutting blade whose cutting chain can be easily removed and replaced.

Another object of the invention is to provide a cutting blade in which the cutting chain is supported on a single disk.

Yet another object of the invention is to provide a cutting blade that is easy to use, economical to manufacture, and durable.

A particular object of the invention is to provide a cutting chain having a link having an anchor link and a central link, each anchor link having an anchor portion extending to one side of the chain;
A circular cutting blade having a circumferentially extending disk having alternating sprocket teeth and tooth grooves, the chain being secured around the disk with an anchor portion received within the tooth grooves. .

These and other objects and advantages of the present invention will become more apparent from the following description when read in conjunction with the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1-3, there is illustrated a cutting blade, generally designated by the reference numeral 10, constructed in accordance with the present invention. The blade 10 has a disk 12 having a generally circular outline.
An arbor receiving bore 14 is arranged in the center of the arbor.

Bore 14 is capable of receiving a motor driven arbor;
This bore secures the disk to a power device operable to drive the disk.

The disc 12 has the configuration of a sprocket with alternating teeth and tooth spaces around its periphery. These sprocket teeth are marked with reference number 16 and the tooth grooves are marked with reference number 18.
is attached. In a preferred embodiment, tooth 16 and tooth groove 1
8 is a line 20.2 extending outward from the center 23 of the disc.
They are each symmetrical about 2. Disk 12 is formed from a single sheet of material such as steel and is therefore easy to manufacture and relatively lightweight.

A cutting chain 24 is placed around the disk 12. Chain 24 is formed of a series of links connected together with pins, like the well-known saw chain. Thus,
Chain 24 has a central or anchor link 26 with an anchor portion 28 extending downwardly into the link. Opposed side links 30 interconnect the central links. These side links consist of cutter links 32
It is. These cutter links are labeled with reference numbers 32A and 32B. These side links are connected to the central link by pins 34 passing through receiving bores in the links.

These cutter links may be similar to conventional saw chain cutter links, as shown in link 32B of FIG. A depth gauge 38 projects from the front of the body portion 36 and a cutting tooth or cutter 40 projects from the rear. The cane and depth gauge are separated by a narrow section or gullet 42. The cutter links include a left cutter link and a right cutter link that extend along the links of the chain and are interspersed with each other. For example, left cutter link 32
A is on the left side of the chain towards the direction of the chain cutting action and the right cutter link 32B is on the right side of the chain towards the direction of the chain cutting action.

It should be noted that the cutting chain is attached to and extends around the disk 12 in a continuous chain. This chain has pin 34
It can be removed from the disk 12 by removing the . A new chain can be installed by securing the free end with suitable pins around the disc.

If desired, an anti-kick pack (such as the saw chain described in U.S. Pat. No. 4,425,830)
An anti-kickback structure may also be used.

Whatever type of chain is used, after it is attached to the disc, it effectively becomes an integral part of the entire cutting blade assembly.

Open spaces 4 in the chain and between successive central links
There are 4. This space is bounded on both sides by opposing side links connecting the two central links.

When the chain is installed in place, sprocket tooth 1
6 extend into these open spaces and multiple pairs of opposed side links are positioned to straddle the sprocket teeth. Anchor portion 28 seats within tooth space 18 of disc 12.

In this way, a positive driving engagement is achieved between the disc and the chain. Side links help to keep the chain from moving laterally away from the disc by straddling the sprocket teeth. This action allows the use of a disc in the form of a single plate to support and propel the chain during the cutting operation. By using only a single plate as a disc, a very lightweight cutting blade can be provided.

Referring now specifically to FIG. 3, it can be seen that the cutting teeth 40 of link 32A extend beyond the thickness of disk 12 to one side of the disk. This cutting tooth on the opposite link (link 32B) extends the same distance to the opposite side of the disk.

With this configuration, chain 24 creates a kerf with a kerf width that is significantly greater than the thickness of disk 12. This allows the disc to pass freely through the cut material.

In a second embodiment of the invention, shown in FIG.
A cutting blade 60 is provided having a disc 62 formed substantially similar to the chain 24 and a chain 64 formed substantially similar to the chain 24 . A pair of side plates 6
6.68 are provided, one on each side of the disc 62, these side plates having peripheral edges that extend at least partially over the tooth slots 18 and thus overlap with the anchor portion of the chain, thereby keeping cuttings away. This is avoided in the area of the tooth groove and the anchor part, and furthermore, lateral displacement of the chain is avoided. The edges of the side plates are below the side links. The side plates 66,68 have the same thickness as the side links 30 of the chain. The additional rubbing of the side plates provides a structure that is thinner than the kerf width formed by the chain cutters. This embodiment of the invention is particularly suitable for felling large standing trees because the side plates add rigidity to the cutting blade.

Referring to FIG. 5, the illustrated cutting blade has a disc 70 similar to disc 12, a portion of which is shown;
The disk 70 has a generally circular profile and further has an arbor receiving bore (not shown) located centrally therein. Sprocket teeth 72 and tooth spaces 74 are provided alternating around the circumference of the disc. A cutting chain 76 is attached around the disc 7°. The chain has a central or anchor link 78 with a depending anchor portion 78a and opposed side links interconnecting the anchor links. These side links are exemplified by side link 80, which is a strap-like connecting link, and side link 82, which is a cutter link. The side links in the set are interconnected to the central link by pins 84.

In the cutter blade of FIG. 5, the disc 70 is provided with notches on one side of the sprocket teeth, thereby extending the circumferential direction of the disc 70, i.e., the length of the chain attached around the disc. A capture portion 86 is configured in the form of a protrusion projecting from the tooth in a direction extending.

Each anchor portion 78a of the anchor link is formed with a capture portion 88 formed on one side in the form of a projection projecting outwardly from the anchor portion in the length direction of the chain. With the chain in place, each anchor link is installed with its anchor portion in the tooth groove and the captured portion of the link below the captured portion 86 that is part of the sprocket tooth. The structure described above has means for interconnecting the anchor link and the disk to prevent radial outward movement of the anchor link. The means more particularly include interengaging capture portions on each of the anchor portions of the link and the sprocket teeth.

Rotating the cutting blade at very high speeds creates centrifugal forces that tend to throw the chain radially outward. This centrifugal force tends to loosen the chain. Pin 84 interconnecting side links and central link during chain manufacturing
are placed in position passing through receiving bores in the links and then flattened at their ends to securely fasten these ends to the side links. Stretching the chain thus formed under tension may damage the pin 84 by causing the anchor to fail in the bore that receives the pin, or in the area where the pin extends between the anchor link and the side link. This causes damage. For the structure shown in FIG. 5, the degree of radial outward movement of the chain caused by centrifugal force is limited, which also limits the degree of slack in the chain of the cutting blade. Thus, losses (Jj) are avoided in the chain.

Thus, a cutting blade is disclosed that supports a cutting chain on a disc operable to bias the chain and retaining the chain thereon.

The disc may be of single layer construction or may be fitted with side plates. Alternating sprocket teeth and tooth slots are arranged around a disk in which an anchor portion of the cutting chain is received within the tooth slots and the sprocket teeth project between the links of the chain.

The invention is not limited to the particular embodiments described above.

This is because modifications may be made without departing from the scope of the invention as set forth in the appended claims.

[Brief explanation of drawings]

1 is a partial plan view of a cutting blade formed in accordance with the present invention; FIG. 2 is an enlarged view of a portion of the cutting blade of FIG. 1; and FIG. 3 is a partial plan view of the cutting blade of FIG. FIG. 4 is a partially cutaway plan view of a modified cutting blade; FIG. 5 is a plan view of a modified cutting blade; FIG. 0...Blade 12...Disc 16...Tooth 8...Tooth groove 24...Cutting chain 6...Anchor link 30...Side link 2...Cutter link

Claims (8)

[Claims] (1) having links having successive pairs of side links distributed longitudinally along the chain interconnected by an intervening central link, said paired side links; are facing and laterally spaced apart from each other, said central link being between side links, certain of said side links being cutter links, and certain of said central links being cutter links; are anchor links, these anchor links having an anchor portion projecting downwardly from the chain and further having a disk around which alternating sprocket teeth and tooth grooves extend, the anchor portion being received in the tooth grooves; A circular cutting blade, characterized in that the chain is secured around the disc with the side links straddling the sprocket teeth, the disc having means for securing it to a power drive. (2) The circular cutting blade of claim (1), wherein the sprocket teeth are symmetrical. (3) The circular cutting blade according to claim (1), characterized in that the tooth spaces are symmetrical. (4) having side plates fixed to said disc on each side of said disc, said side plates having peripheral edges extending beyond the tooth grooves and overlapping the lower peripheral edges of the anchor portion and side links; Circular cutting blade according to claim 1, characterized in that: (5) a circular disk having sprocket teeth circumferentially distributed around the disk and tooth grooves interposed between these sprocket teeth and circumferentially distributed around the disk; a cutting chain mounted circumferentially on the periphery and extending as a continuous chain, said cutting chain having opposed side links interposed by a central link, said central link projecting downwardly from said chain and extending as a continuous chain; a link with an anchor portion seated in a tooth groove, said side link having a cutter link with a cutter portion projecting radially outwardly from the disc, and further having one side on one side of said disc. a pair of side plates fixed to the disk with the other positioned on the other side of the disk, the side plates extending over the tooth grooves and below the anchor portion and the side links; A circular cutting blade characterized in that the blade has a circumferential edge that overlaps a circumferential edge. 6. A circular cut according to claim 1, further comprising means for interconnecting at least selected anchor links and said disc to prevent radial outward movement of said anchor links. blade. (7) the means for inhibiting movement of the anchor link has a first catch portion on the anchor link and a second catch portion on the disk, the first and second catch portions comprising:
Circular cutting blade according to claim 6, characterized in that it interengages with anchor links received in tooth grooves of the disc. (8) The first catching part is a first protrusion of an anchor part of an anchor link that projects in the length direction of the chain, and the second catching part is a sprocket of a disc that projects above the first protrusion. Circular cutting blade according to claim 7, characterized in that it is the second protrusion of the tooth.