US3135304A

US3135304A - Roto saw

Info

Publication number: US3135304A
Authority: US
Inventors: Carl F Breer; Gudmundsen Austin
Original assignee: Mcculloch Corp
Current assignee: Mcculloch Corp
Priority date: 1959-09-14
Filing date: 1959-09-14
Publication date: 1964-06-02
Anticipated expiration: 1981-06-02

Description

June 1964 c. F. BREER ETAL 3,135,304

ROTO SAW Filed Sept. 14, 1959 2 Sheets-Sheet l 0m F BREE/P AUSTIN Gl/flMU/VDStW,

INVENTORS.

WHANN a McMAN/GAL Af/omeys fbr Anal/km June 2, 1964 c. F. BREER ETAL ROTO SAW Fil ed Sept. 14, 1959 2 Sheets-Sheet 2 N F. 5 5 HM a 6 w y A M INVENTOR5. Wl-IANN 8 Mc MAN/GAL Alf/always fbr A a 071E001 United States Patent Filed Sept. 14, 1959, Ser. No. 839,830 9 Claims. ((11. 143-44) This invention relates generally to power-driven saws and relates more particularly to annular rotary saws.

While the invention has particular utility embodied in manually-portable annular power-driven saws, and is shown and described embodied therein, it is to be understood that its utility is not confined thereto.

As is well-known, saw chains of bow saws have an appreciable amount of vibration so that the kerf is wider than the saw chain. Such vibration also tends to cause a substantial amount of wear.

It is an object of the present invention to provide a manually-portable power-driven saw wherein these disadvantages are overcome.

It is another object of the invention to provide mechanism of this character having an annual ring which carries the saw teeth.

Still another object of the invention is to provide a device or mechanism of this character wherein said ring is rigid and held against appreciable lateral vibrations.

It is a further object of the invention to provide mechanism of this character wherein the width of the kerf is held to aminimum. The ring is carried by an unbroken bearing arrangement which stabilizes the ring and minimizes vibration thereof. A further advantage of this absorb cutting shocks and reduce operator fatigue as well as increase the life of the parts. using a belt drive.

A further object of the invention is to provide a mechanism of this character having automatic belt tightening means.

A still further object of the invention is to provide a mechanism of this character having means to prevent This is effected by .whipping of the belt.

Another object of the invention is to provide a mechanism of this character that may be easily and quickly detached and attached to the motor.

Another object of the invention is to provide a mechanism of this character having effective and efficien-t oiling means for the oiling of the gear and pinion.

Still another object of the invention is to provide a mechanism of this character having an effective and efficient means for oiling the rotor.

A further object of the invention is to provide a mechanism of this character having means for adjusting the guide ring to compensate for wear.

A still further object of the invention is to provide mechanism of this character that is relatively light in weight so that it is easy to handle by the operator.

A still further object of the invention is to provide a mechanism of this character that is relatively inexpensive to assemble and service.

The characteristics and advantages of the invention are further sufliciently refered to in connection with the following detailed description of the accompanying drawings which represent certain embodiments. After considering "ice these examples, skilled persons will understand that many variations may be made without departing from the principles disclosed, and we contemplate the employment of any structures, arrangements or modes of operation that are properly within the scopeof the appended claims.

Referring to the drawings which are for illustrative purposes only:

FIG. 1 is a side view of a manually-portable, poweroperated, annular rotary saw embodying the present invention;

FIG. 2 is an enlarged, fragementary side view, partially in section, showing the drive connection with the rotary ring:

FIG. 3 is a sectional view taken on line 33 of FIG. 2;

FIG. 4 is a sectional view taken on line 44 of FIG. 1;

FIG. 5 is a sectional view taken on line 5-5 of FIG. 1;

FIG. 6 is a view similar to FIG. 5 but showing an alternative arrangement:

FIG. 7 is a reduced side view of the rotor guide;

FIG. 8 is a side view of a portion of the gear assembly ring of the rotor; and

FIG. 9 is a fragmentary side view of the alternative arrangement of the annular rotor having the tooth arrangement shown in FIG. 6.

Referring more particularly to FIG. 1, there is shown a motor or engine assembly, indicated generally at 12, and a saw mechanism or assembly, indicated generally at 14.

The motor or engine assembly 12 is of well-known type and character and includes a clutch mechanism, also of well-known character. This clutch mechanism includes a pulley and bearing assembly, indicated generally at 15 comprising a drum 18 with a driving pulley 19 secured thereto by any well-known means, said pulley 19 having a peripheral, V-shaped groove 19a therein.

The saw mechanism 14 includes a mounting frame, indicated generally at 20, comprising an elongated plate 21 having a tongue 22 extending rearwardly from the plate 21 and offset laterally therefrom as at 23, the plane of said tongue being parallel to the plane of the plate. Tongue 22 is provided with an opening 24 therein intermediate its ends and a notch 25 extending inwardly from the free end of said tongue, said opening and notch being adapted to receive screws, not shown, for attachment of the saw assembly to the frame, also not shown, of the engine assembly 12 so that the mounting frame of the saw assembly extends forwardly of the engine.

Adjacent the forward end of the mounting frame, there is a bearing support 25 which extends laterally at one side of said frame and which is integral therewith. Bearing support 25 has a passage .therethrough and at the fixed end of the bearing support said passage opens into an oil recess 26 opening from the opposite side of said frame.

Disposed within the bearing support 25 is a drive pinion bearing 27 secured against axial displacement by means of a wire retaining ring 28. Rotatable within the bearing 27 is a pinion shaft 28a having an end portion 29 extending axially therefrom in one direction and an outwardly extending portion 30 at the opposite end.

Within the recess 26 is disposed an oiler felt 31 secured in said recess by an oiler felt retainer 32 which is secured in the recess 26 by means of a cover 33 of shallow, cupshape form having a plurality of cars 34 annularly spaced apart about the open side of said cover, said ears having openings provided therein for reception of screws 35 which in turn are screwed into tapped openings in the adjacent portion of the mounting frame whereby said cover is secured to said mounting frame.

A pinion 38 is fixed to the shaft portion 29 by any suitable means such as a key, not shown. The side of the mounting frame at which the recess 26 opens is provided with a generally arcuate flange which extends from the forward end of the mounting frame to a point at the forward side of the recess 26, arcuately about the upper edge of the recess, as at 41, to a point substantially diametrically opposite the point said flange begins to follow the upper half of said recess, and thence arcuately upwardly at 42 to the upper end of an extension 43 which extends upwardly of the plate 21 adjacent the rear end thereof. The same side of the plate and extension is provided with a flange 44 which also extends laterally of the plate of the mounting frame and arcuately in substantially parallel relationship to the part 42 of the upper flange 4-0. Flanges 49 and 44 are formed integrally of the plate 21, and there is defined between said flange portion 42 and the flange 44 a channel, the botom of which is defined by the portion of the plate 21 between said flanges.

Means is provided for mounting a gear assembly ring, indicated generally at 50, and said means comprises a rotor guide shown diagrammatically at 51 in FIG. 7 and which is ring-shaped and is provided with a peripheral groove 52. The guide 51 is also provided with an arcuate notch 53, FIG. 7, and at the deepest part of this notch said guide is split, as at 54, although it is to be understood that the split may be at some other part of the ring 50. For example, it may be desirable to have the split just ahead of the slot or 61 (FIG. 2) which would permit greater adjustment range without disturbing the oil seal area around the pinion.

Guide ring 51 is disposed against the plate 21 with a portion thereof in the channel defined by the flange portion 42 andthe flange 44. An arcuate guard 58 is provided along a rear portion of the guide and said guard has a flange 59 extending along the interior edge thereof. The flange is provided with a plurality of elongated spaced openings 60 for reception of screws at which also extend through corresponding elongated openings provided therefor in the guide and in the plate 21 and extension 43. Nuts, not shown, are provided on the free ends of the screws whereby the guard and guide are securely attached to said plate and extension. When the guide is thus attached, the notch 53 is in register with the lower portion of the recess 26. The screws 61 attach the portion of the guide at one side of the split 54 andscrews 63, received in openings provided therefor in the guide adjacent the other side of said split, extend through openings provided therefor in the plate 21 and have nuts for tightening same to thereby secure the portion of the guide at the opposite side of said split to said plate 21. I

The screws 63 also secure a pair of spikes 64 at opposite sides of the plate 21, said spikes extending forwardly and downwardly of said plate.

Disposed in the peripheral groove 52 of the rotor guide 51, is a ring gear having teeth 76a along the inner edge portion, the free ends of said teeth riding on the bottom Wall of the groove 52 so that said gear has maximum support and long wear, which are exposed in the notch 53 0f the guide and mesh with the pinion 38, as best shown in FIG. 2.

An outer peripheral portion of the ring gear extends radially beyond the outer peripheral edge of the guide 51. This peripheral edge portion of the gear ring '79 has a plurality of elongated notches '73 which are annularly spaced apart about the ring, said notches extendinginwardly from the outer peripheral edge of said ring.

Disposed in each notch 73 is a cutter, said cutters being allochirally arranged and said cutters are indicated as 75a and 75b. These cutters are secured by rivets 76 to side straps, or rotor or hearing rings 78 at opposite sides of the peripheral portion of the gear ring and secured thereto by means of rivets '79. The internal edges of the rings 78 ride or rotate on the respective peripheral edge portions 89 of the rotor guide 51 at opposite sides of the groove 52 thereof. 7

There is a pulley, indicated generally at 99, having a V-shape peripheral groove 91, said pulley being formed of sheet material and having a central recess 92 into which the bearing support extends. At the outer end of said recess, the pulley is provided with a wall 93 having an opening therein for reception of an axially extending part 94 of a hub 95 which is secured to the end portion 30 of the shaft to which the pinion 38 is attached. The hub and wall 93 are secured together by screws 95'.

Groove 91 of pulley 90 is in alignment with a peripheral, V-shape groove 96 of an idler pulley 97 rotatably mounted on a shaft 98 secured in an opening provided therefor in the mounting frame plate 21. Any suitable means may be used to retain the idler pulley 97 on the shaft 98. One such means may be a retaining ring 99 disposed in an annular groove provided therefor in the outer end portion of the shaft 98. A washer, not shown, may be disposed between the retaining ring 99 and the adjacent portion of the pulley 97.

When the mounting frame is secured to the engine assembly, the pulleys 90 and 97 are in operative alignment with the drive pulley 19 of the engine, said pulley 19 also having a V -shape groove 1% and a drive belt 100 is disposed in the grooves of said pulleys so that rotation of the pulley 19 by the engine will effect rotation of the pulley 90 which, in turn, will effect rotation of the pinion shaft and pinion 38 so that the latter will rotate the gear ring 70, rotation of the gear ring and, hence, the cutters is in a clockwise direction, as viewed in FIGS. 1 and 2, and cuttings thrown off bythe cutters will strike a sawdust deflector 191, FIGS. 1 and 2, which is attached by means of a screw 192 to a depending boss 103 adjacent the forward end of the mounting frame plate 21.

It is to be noted that the guard 58 with adjacent portions of the plate 21 and extension 43 cover a rearportion of the cutting mechanism and that portion of the guard, indicated at 105 which extends upwardly of the upper end of the extension 43 is formed to provide a tubular enclosure 58a for the cutting mechanism, this arrangement being best shown in FIG. 5, the part 58a including an arcuate flange 195' arranged in parallel relationship to the flange 59, the flanges 59 and 105' being disposed at opposite sides of the rotor guide and the ends thereof being secured to said guide by means of a screw 1%, FIG. 1.

The oiler felt 31 disposed in the recess 26 is supplied with oil from the engine or any other suitable source. The oil travels through to the passage in the tongue 22, said passage having. one end of an oil tube 111 disposed therein, said tube being secured to the plate 21 by means of a clip 112 attached to a boss 113 of the plate 21 by means of a screw 114. The opposite end of the tube 111 is connected to a short oil tube 116 by means of an oil tube hose 117. Tube 116 is press fitted or otherwise secured in a short bore 118 in the plate 21 and said bore 118 communicates with a bore 119 which leads to the bottom of the recess 26 inwhich the oiler felt 31 is disposed and which aids in retaining oil in the recess 26 for oiling the drive pinion bearing.

Oil in the recess 26 soaks into a pair of felt strips 12%) disposed at the sides of the guide 51 and overlapping inner edge portions of the rings 78. vOne of the felt strips is between one side of the guide 51 and a ring 78 and the plate 21 and extension 43, said strip extending upwardly to the free end of the guard. The other strip is between the other side of the guide 51 and other ring 78 and the flange 59 of the guard. The lower ends of the felt strips 120 extend into the recess 26 so as to receive lubricant therefrom and the lubricant is carried throughout the strips 120 in the usual manner by capillary action. Thus, throughout asubstantial portion of the circumference of the cutting mechanism, the bearing surfaces tltland' the inner edges of the rings '78 are lubricated and oil or other lubricant is carried around the rest of the circumference of the guide and rings 78.

Means is provided to adjust the diameter of the guide to the guide 51 at a point spaced somewhat upwardly of the upper end of the extension 43, said bracket having a tubular part 126 arranged at substantially right angles to the upper edge of said extension. Tubular part 126 is internally threaded for reception of an adjusting screw 127 having a head 128 at the lower end of the bracket and in engagement with the upper edge of said extension.

In order to adjust the diameter of the guide 51 to compensate for wear between said guide and the rings 78, the screws 61 are loosened and the screws 35 of the pinion cover 33. The adjusting screw 127 is then turned so that the head 128 reacts against the upper edge of the extension '43 and forces the adjacent portion of the guide at the left-hand side of the split, as shown in FIGS. 1 and 2, upwardly thereby increasing the diameter of said guide. The screws 61 and 35 are then tightened. It is to be understood that the guide 51 is increased in diameter sufficiently to take up wear between it and the rings 78 but to leave enough clearance so that the parts do not bind.

A pulley cover 130 is attached to the plate 21 and encloses both the pulley 90 and the pulley 97. The cover 130 defines a shallow chamber in which said pulleys are disposed and the cover is secured to the plate by means of screws, including screws 131 which extend through openings provided in the plate 21 and into tapped openings in bosses formed integrally of the cover.

There is means for adjusting the tension of the belt and said means includes a tension adjustment bolt 135 having an inner end portion loosely received in openings 136 in the forward and rearward end walls 137 and 138 defining an opening 139 in which a floating nut 140' on the bolt is exposed. The bolt 135 has a head 140 at its rearward end and slidable on said bolt are forward and rearward spring guides 141 and 142 againts end

flanges

143 and 144 of Said guides respectively the ends of a tension spring 145 react. The flanged end of the guide 141 abuts against the Wall 138 while the flange of the guide 142 abuts against the head 140 of the tensioning bolt and urges same rearwardly.

Normally the tension of the belt will be established when the saw assembly is attached to the engine assembly. At this time the mounting bolts whereby the tongue 22 is attached to the engine frame are tightened only finger tight. The tensioning bolt 135 is turned so that the head 140 thereof engages the chain oiler reservoir, not shown, of the engine. The screw is turned until the floating nut, which has up to this time been in engagement with the wall 133, moves away from said wall sufficiently to allow relative separation of the saw assembly and the motor assembly for effecting the proper tensioning of the belt. When the floating nut is spaced aproximately a quarter of an inch from the wall 138, there is suflicient clearance so that the spring will exert tension against the oiler reservoir and stretch the belt to the correct tension. Approximately one hundred pounds pressure is provided to give the belt the correct tension. The mounting bolts are then tightened securely.

In the arrangement disclosed in FIGS. 6 and 9, the allochirally arranged cutters LH and RH are attached to the gear ring at alternate sides thereof by means of rivets or the like 150. The cutters of one side are spaced apart a predetermined distance on the ring 7 0 and the cutters on the other side are similarly spaced apart but are located midway relative to the spacing of the cutters of said one side. Between the cutters at the respective sides are connecting links 151 which are arcuate in shape and have the same curvature as the ring gear 70. The links are secured to the respective sides of the gear ring by means of rivets 152 and it is to be noted that the rivets 150 not only extend through the gear ring but also extend through the links at the opposite side of the gear ring.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it is believed that it will be apparent that various changes maybe made in the form, construction and arrangement of the parts of the invention without departing from the spirit and scope thereof or sacrificing all of its material advantages, the embodiments hereinbefore described being merely for purposes of illustration.

We claim:

1. A rotary saw, comprising: a mounting frame having a recess in one side adjacent the forward end thereof and a bearing support extending from the opposite side and in axial arrangement with said recess; a bearing in said bearing support; a shaft rotatable in said bearing and having end portions extending outwardly of the respective ends of the bearing, one of said end portions extending into the recess; a drive pulley attached to the other end portion of said shaft; a pinion secured to the end portion of the shaft projecting into the recess; an annular rotor guide secured to the side of the mounting frame having the recess therein, said rotor guide having a peripheral groove therein and an arcuate notch in the inner edge portion registering with a portion of said recess and accommodating the pinion, said notch extending into the adjacent inner part of the peripheral groove; an internally toothed annular ring gear disposed in the peripheral groove of the guide with the teeth, exposed by said arcuate notch, meshing with the pinion, said ring gear having annularly spaced notches in the periphery thereof; allochirally arranged cutters in the respective peripheral notches of the ring gear; and a bearing ring at each side of the outer peripheral portion of the ring gear, said bearing rings being secured to the ring gear and said cutters being secured to the bearing rings, the internal diameter of said bearing rings being such that said bearing rings operably ride on the peripheral edge portions of the rotor guide at the sides of the peripheral groove thereof, said edge portions providing bearing areas.

2. A rotary saw, comprising: a mounting frame having a recess in one side adjacent the forward end thereof; a shaft rotatably carried by said frame and having an end portion extending into the recess; a drive pulley attached to the other end of said shaft; a pinion secured to the first end portion of the shaft extending into the recess; an annular rotor guide secured to the side of the mounting frame having the recess therein, said rotor guide having a peripheral groove therein and a notch extending into the adjacent inner part of the peripheral groove, said guide being split at said notch; an internally toothed annular ring gear disposed in the peripheral groove of the guide with the teeth exposed by said notch meshing with the pinion, said ring gear having annularly spaced notches in the periphery thereof; allochirally arranged cutters in the respective peripheral notches of the ring gear; a rotor ring at each side of the outer peripheral portion of the ring gear, said rotor rings being secured to the ring gear and said cutters being secured to the rotor rings, the internal diameter of said rotor rings being such as to operably ride on the peripheral edge portions of the rotor guide at the sides of the peripheral groove thereof; and means for expanding the split rotor guide to compensate for wear.

3. A rotary saw, comprising: a mounting frame; an annular rotor guide secured to the mounting frame, said rotor guide having a peripheral groove therein; a retatable assembly including an internally toothed annular ring gear disposed in the peripheral groove of the guide; side members attached to peripheral portions of the ring gear, said members being slidable on the peripheral edge portions of the rotor guide at the sides of the peripheral groove thereof; cutters carried by said rotatable assembly; and lubricant carrying material secured to the sides of portions of the guide and overlapping the plane of the peripheral edge portions thereof to provide lubricant to said edge portions.

4. The invention defined by claim 3, including means for conveying lubricant under pressure to said material.

5. The invention defined by claim 3 including a driving gear for said ring gear; lubricant carrying material for supplying lubricant to said gears, said material being in lubricant transfer relation with said material at the sides of said guide; and means adapted to be connected with a source of lubricant, supplying lubricant to the lubricant carrying material for the gears.

6. In a rotor assembly: an annular guide having a peripheral groove therein; and a rotor assembly including an internally toothed ring gear rotatably mounted in said groove, the free ends of said teeth operably riding on the bottom of said groove, replaceable cutters spaced longitudinally about the ring gear, and elements at the sides of the ring gear and disposed along a peripheral edge portion of said ring gear; and means securing said elements, cutters and ring gear together, said elements operably riding on the peripheral edge portion at the side of the groove.

7. A rotor assembly, comprising: an annular guide ring having a peripheral groove therein; a ring gear operably disposed in said groove and having a peripheral edge portion extending outwardly of the guide, said ring gear having a plurality of annularly spaced notches in the periphery thereof; cutters disposed in said notches and having cutting parts extending outwardly of the periphery of said ring gear; and rotor rings at the sides of said peripheral portions of the ring gear, said rotor rings being rotatably mounted on the edge portions of the guide ring at the respective sides of the peripheral groove thereof; and means securing said rotor rings to the peripheral portion of the ring gear and securing the cutters between said rotor rings.

8. In a rotor assembly: a ring gear having annularly .spaced notches extending inwardly from the peripheral internal diameter of said rotor ring being less than the internal diameter of the ring gear; and cutters having portions disposed in the peripheral notches of the ring gearv and secured to and between the rotor rings, said rotor rings being secured to the ring gear.

9. A rotary saw, comprising: a mounting frame; an annular rotor guide secured to the mounting frame; said rotor guide having a peripheral groove therein; a rotatable assembly includingan internally toothed annular ring gear disposed in the peripheral groove of the guide; side members attached to peripheral portions of the ring gear, said members being slidable on the peripheral edge portions of the rotor guide at the sides of the peripheral groove thereof; cutters carried by said rotatable assembly; and a tubular guardfor a rear portion of the guide and rotatable assembly, said guard being arcuate and including a portion secured to the mounting frame and a portion extending upwardly therefrom fully surrounding the part of the guide and rotatable assembly disposed therein.

References Cited in the file of this patent UNITED STATES PATENTS 368,618 Proctor Aug. 23, 1887 1,083,663 Carpenter -a Jan. 6, 1914 1,395,101 Fite Oct. 25, 1921 1,562,732 Arsneau Nov. 24, 1925 2,184,461 Mall Dec. 26, 1939 2,327,233 Wolf Aug. 17, 1943 2,532,981 Wolfe Dec. 5, 1950 2,771,919 Cox Nov. 27, 1956 2,783,794 Kroll Mar. 5, 1957 2,804,105 Stone Aug. 27, 1957 2,902,068 Gudmundsen Sept. 1, 1959 FOREIGN PATENTS 83,163 Switzerland Nov. 17, 1919 900,493 Germany Dec. 28, 1953