US2630844A

US2630844A - Chain saw

Info

Publication number: US2630844A
Application number: US170966A
Authority: US
Inventors: Abbott John Allan; George H Barber; Albert K Newman; Lillian K Schindler
Original assignee: HOMCLITE CORP
Current assignee: HOMCLITE Corp
Priority date: 1950-06-29
Filing date: 1950-06-29
Publication date: 1953-03-10
Anticipated expiration: 1970-03-10

Description

March 10, 1953 J. A. ABBOTT ErAL 2,630,344

CHAIN SAW Filed June 29, 1950 l 6 Sheets-Sheet l March 10, 1953 J. A. ABBOTT ErAL v2,630,844

CHAIN SAW Filed June 29, 195o e sheets-sheet 2 m N e;

- le w QQ w .gx u n \1 Qq; N

s; oa.

x4 0 a w Q, i@ 4 `N o, w lo n ...v1 Q Ch m.

IN VEN TORS March 10, 1953 J. A. ABBT'r Erm.

CHAIN SAW 6 Sheets-Sheet 3 Filed June 29, 1950 10 4.. Z 6 6 3. oa 4. 1 9m! .f4 1 53 20v 9 7 o 6 w ao 6 fg@ w v O 0o 5 .a5 7 .M \f 4. n a r/u 4 7 L W 0 2 v J u.. a n. f M Y .3 fwwn. 5 Z 5 a M W uw. 0 'h M m ww Il .a M y W. .a Lv M M e@ Mar-11110, 1953 J, A. ABBOTT HAL y 2,630,844

CHAIN SAW Filed June 29, 1950 6 Sheets-Sheet 4 A INVENTORS A TTORNEX March 10, 1953 i v.1. A. ABBOTT ErAL 2,630,844

CHAIN SAW Filed June 29, 1950 6 Sheets-Sheet 5 Y o G o 0 n a o W @I 5 @I A TTmQA/EX March l0, 1953 J. A. ABBOTT ETAL 2,630,844

CHAIN SAW Filed June 29, 1950 6 Sheets-Sheet 6 A TTOK/VEK Patented Mar. 10,I 1953 UNITED STATES PATENT OFFICE CHAIN SAW Application June 29, 1950, Serial No. v170;)36

21 Claims.

The present invention relates to chain saws and particularly to chain saws driv-en by internal combustion engines.

In order to be used for cutting 4dovvn trees and also for cutting up trees after they are felled, it is necessary for a chain ,saw to operate in a felling position With the saw chain in a. horizontal plane and also in a bucking position with the saw chain in a Verticalplane. Moreover, Vit is desirable for the saw to be ,able 4 to tiltat least 30 in any direction from the normal felling and bucking positions.

The operation of thBsaW in these various positions gives rise to a number of problems. In the rst place, there ,is -a problem of supplying a proper fuel-air mixture to the engine .since the carburetor of an internal combustion engine has to remain right side up to function properly. There is also the problem of getting fuel from the fuel tank to the carburetor in all positions of the saw and of preventing leakage of fuel through the vent hole thatis normally provided in the filler cap of the fuel tankand isneeessary in order to admit air `as the fuel is used up.

Manipulation of the saw to turn itfrom one posi- L.

tion to another and tohold'it in all cuttin'gpositions with minimum effort on the part of the operator, and hence with minimum` fatigue, is a further related problemthatjarises vfrom the need 'then start the saW fand pickit up again,

It has also been `proposed .to mount the carburetor so it can begturnedjto oneposition when felling and `another position when bucking. However, with jth'e arrangements heretofore available, it has been exceedingly inconvenient to turn the carburetor and the saw vat ythe same time while the lsavv is running. yDifficulty has also been experienced in maintaining a constant supply of fuel from the fuel tank to the carburetor and engine in all positions of the saw. This is particularly true when the fuel tank is partly empty. Moreover, the arrangement of handles on the saw has made it inconvenient and awkferent positions.

CFI

.Another expedient that has been proposed is to use a pressure fuel system in conjunction With a fuel injection arrangement intended to Work in any position of .the saw. Such .an arrangement has been found to be so complicated that it is difficult to keep in proper operating condition. As most lumbermen are not highly skilled mechanics, theycannot ,be relied on to service such equipment. A further objecltonvarises from the fact that the fuel supply system does not Work uniformly in all positionsof the saw. There has hence never been a Wholly satisfactory solution to the problem of operating a chain saw in all of the positions normally required for felling and bucking.

It is an object of the present invention to provide a chain saw of improved construction which will operate equally Well in all cutting positions and which can be turned from one position to another quickly and easily Without stopping the engine. In all positions Aof the saw, in accordance with the invention, the operators hands are held naturally so that there is minimum strain and fatigue. In fact, the operators hands are held in substantially 'the same position for both felling and bucking. Innormal operation of the saw, Vtheoperator need never remove his hands from the handles.

Another object of the present invention is to provide asimplied fuel system in which asimple float type carburetorfis used andfuel is fed by gravityfrom the fuel .tank to the carburetor in all cutting positionsof the saw. The fuel tank is divided into a plurality of interconnected compartments arranged in suchmanner that, even when the saw is tipped so that arnajor portion of the fuel tank is below the fuel outlet leading to the carburetonsufcient fuel is trapped and held in the compartment Wi-.thwhichthe fuel line. is connected to yrun theengne during its operation in this position. This istrueeventhough the fuel tank .may .benearly empty. There is no fuel pressure-system orv other complication. In. conjunctionwiththese features, the fuel tank isprovided with a-novel venting system which vents the tank While-'avoiding 'leakage -of fuel despite the diierentvpositionsto which the saw is turned and even with a full tank.

Other featureaobjectsvand advantages of the invention will appear from the following dep scription v.and vclaims 'andffrom the accompanying drawings which show, by way -of enamplegtwo embodiments of our invention. Certain features ofthecliain vsaw are 'morfully described 'inour 3 companion application Serial No. 167,596 filed June 12, 1950.

In the drawings:

Fig. 1 is a plan view of a chain saw in accordance with the invention, the saw being shown in bucking position. Only a portion of the chain support and cutting chain is shown.

Fig. 2 is a side elevation from the left hand side of the saw shown in Fig. 1.

Fig. 3 is a side elevation on a larger scale of the right hand side of the saw with most of the chain support and chain omitted.

Fig. 4 is a vertical section through the fuel tank and the carburetor, the approximate location of the section being indicated by the line 4 4 in Fig. l.

Fig. 5 is a rear View of the chain saw, certain portions being omitted and a portion of the fuel tank wall being broken away to show internal construction.

Fig. 6 is a horizontal section on a larger scale taken through the carburetor and associated parts, the position of the section being approximately on the line 6 5 in Fig. 4.

Fig. 7 is a side elevation of another embodiment of the invention, showing the right hand side of the saw.

Fig. 8 is a rear elevation of the chain saw shown in Fig. 7 with portions broken away to show interior structure in section.

Fig. 9 is a side elevation on a smaller scale showing the left hand side of the chain saw of Fig. 7.

The chain saw illustrated in Figs. l to 6 of the drawings comprises a frame or chassis, a chain support mounted in fixed position on the chassis, a cutting chain running on the chain support, an internal combustion engine, a power transmission system including an automatic clutch between the engine and a driving sprocket for the cutting chain, a fuel supply system for the engine including a fuel tank of novel construction, a carburetor mounted in a novel manner, a novel air intake assembly and an intake manifold and a novel arrangement of handles for holding and manipulating the chain saw, one of the handles being connected with the carburetor so as automatically to keep the carburetor upright when the saw is turned from felling to bucking position and vice versa, and a throttle control associated with the latter handle.

The frame or chassis I comprises the stationary portions of the chain saw on which other parts are mounted, the terms being used somewhat flexibly in that certain parts are at times referred to specifically and at other times are included in the generic designation of frame or chassis.

The chain support 2 is preferably in the form of a beaver tail shaped supporting plate of known type over which the cutting chain runs. It is mounted in xed position on the chassis I in a vertical plane and with its central longitudinal axis at an angle to the horizontal, as seen in Fig. 2. For a two-man saw, the chain support is provided with a handle at its outer end. The handle is omitted or removed when the saw is to be used by a single operator. The cutting chain 3 comprises a flexible chain on which cutting teeth and rake teeth are provided and may be of known or suitable type. The outer edge of the chain support r2 is provided with a bearing surface over which the cutting chain runs.

The engine 4 is shown as a one-cylinder twocycle internal combustion engine having a horizontal cylinder 5, spark plug 6, crank shaft 1 and crank case 8. At its left hand end, as viewed from the rear of the saw, the crank shaft carries a ily wheel and fan which are enclosed in an approximately circular fly wheel housing 9. A cable-type starter having a starting handle i0 (Fig. 2) is also provided at the left hand side of the saw.

Power from the engine is transmitted to a sprocket for driving the cutting chain 3 through a transmission including an automatic clutch which is shown and described in the above mentioned companion application. The transmission is disposed at the right hand side of the engine and is enclosed in a transmission housing i2 (Figs. 1 and 3). An arcuate series of points or teeth I3 provided on the transmission housing adjacent the base of the chain supporting plate 2 is adapted to engage the work and act as a fulcrum in feeding the cutting chain into the work.

The fuel system for the engine comprises a fuel tank ill, a carburetor l5 to which fuel is supplied from the tank by ilexible tubing i6, an air intake assembly Il (Fig. 5) for supplying air to the carburetor and an intake manifold i8 leading from the carburetor to the crank case of the engine,

The fuel tank It is approximately L-shaped in side view and comprises an upper main chamber 20 overlying the engine, and a lower auxiliary chamber 2i projecting downwardly from the rear portion of the main chamber. The tank has

side walls

22 and 23, an outer wall 24 which is approximately semi-circular and forms the top and the rear side of the tank and a bottom wall 25 comprising an approximately horizontal portion 26 which overlies the engine and forms the bottom of the main chamber 28, a downwardly extending portion 2l which lies to the rear of the engine and forms the front wall of the auxiliary chamber 2| and a rearwardly extending portion 28 which joins the lower rear edge of the outer wall 211 and forms the bottom of the auxiliary chamber 2 i. The radius of the arcuate outer wall 24 is approximately the same as that of the fly wheel housing 9 so that the outlines of the fuel tank blend into those of the fly wheel housing. As will be seen in Fig. 4, the fuel tank fits compactly over the engine. It also blends in with the transmission housing l2 to provide maximum compactness and neatness of appearance.

The main chamber 2U and auxiliary chamber 2l of the fuel tank are partially separated from one another by a partition or baie 3d which is approximately horizontal and forms in effect a continuation of the horizontal portion 26 of the bottom wall 25 (Fig. 4) The partition 30 joins the bottom Wall 25, the rearward portion of the outer wall 24 and the right side wall 23, with substantially fluid-tight joints but the left hand end of the partition is spaced a short distance away from the left hand side wall 22 of the tank to provide a communicating opening 3l (Fig. 5) between the upper main chamber 20 and the lower auxiliary chamber 2l.

The lower chamber 2l is divided -by a. partition or baille 32 into two

compartments

33 and 35.. The partition 32 is approximately vertical and joins the partition 30 and portions 2l and 28 of the bottom wall 25 with substantially fluidtight joints. The rear edge of the partition 32 is spaced a slight distance from the rearward portion of the outer wal'l 25 so as to provide a communicating opening 35 (Fig. 1) between the two

compartments

33 and 34. The partition 32 is located nearer the right hand side of the fuel tank, being spaced from the right hand end of the chamber 2! a distance equal to apiproXimately one-third to one-fifth the width of the tank.

The fuel tank is provided with an outlet opening 3S which is located at the lower front right hand corner of the compartment 3d and preferably provided with a suitable shut-olf valve. The exible tube iE (Fig. S) leads from this outlet to the carburetor i5. The tank is also Iprovided with a Vlling opening 3'! located in the upper portion vof the outer Wall 3a. The filling opening 3l is surrounded by a downwardly projecting skirt 33 (Figs. 4 and 5) and is provided with a removable filler cap 39. The removable closure 3S is liquid-tig ft and airtight and in this respect is unlike :the usual filler cap which is provided with a small vent opening.

The venting of the fuel tank to admit air as the fuel is 'used up and vthereby avoid the creation of a vacuum in the tank is provided by the arrangement of openings, cups and tubes illustrated in Figs. 1, l `and 5. A vent cup el is provided on the upper portion of the cuter wall of the yfuel tank at the right hand side of the tank and preferably is slightly forward of the upper- Y most lportion or the wall 24 when the saw is in the horizontal position illustrated in Fig. li. A second vent ycup i2 is provided on the outer wall near the left hand side of the tank 'and to the rear of the vent cup Lil. As seen in Fig. 4., the vent 'cup 152 is disposed at an 'angle 'of approxi mately 45 from 'the cup il! and is hence lower when `the saw is in horizontal posi-tion. While the vent cups t! and l2 are `shown as being aiiixed to the inner surface of the -outer wall of the tank with a fluid-tight joint, they may, if desired, be on the outside. The vent cup lil is in communication vwith'the atmosphere through a small vent hole i3 located in the rearward portion of the cup. The vent cup 4'2 communica-tes with the atmosphere through a small vent opening dd located in the forward and upper portion of the cuo.

A vent tube i5 extends rearwardly yand toward the left from the vent cup 4i and terminates near the vent cup iig. .As seen in Figs. 1, 4 and 5, the open end d of the tube i5 opens into the interior of the `tank at 4a 'point adjacent the side wall ci the cup and located above and to the left of the center of Athe cup. A vent tube il extends upwardly, forwardly and to the right from rthe vent cup 122 and terminates adjacent the vent cup fil. As illustrated in the drawings, the open end it of the vent tube 41 is located between the side `wall of the vent cup M and the right side wall 23 of the tank. The vent tubes 45 and if? follow the curvature of the youter wall of the tan-k and are shown afxed tothe inner surface of the tank wall.

The arrangement of vent tubes, cups and openings described above has been found to provide proper venting of the tank in all of the operative .positions of the saw without permitting leakage of fuel. The cups il and 42 provide storage space for receiving fuel which drains from the tubes d5 and Il? when the saw is tilted in certain positions. Otherwise, this fuel might escape through the openings 43 and 4d. When the fuel drains from the vent cups back into the fop-ii tank. The arrangement is such that the operi end of at least one of the vent tubes is always in the -air space above the fuel in all operative positions of the saw.

The carburetor I5 is a float-'type carburetor having a iioat chamber 5D, an annular float 5|, needle valve 52, a butteriiy-type choke valve `53 located in an air inlet passage 54 and a similar throttle 55 located in an outlet passage 5E for the fuel-air mixture. kTo provide good idling characteristics, the carburetor also has an idling air valve 51 :and mixing chamber 58 from which a fusi-air mixture is led to the engine through a passageway 59 and a flexible tube 'Bil when the engine is running at idling speed.

To operate properly, a float-type carburetor needs to be kept right side up. In accordance with the present invention, .provision is made for maintaining the carburetor upright at all times while permitting the saw to be turned through an angle of '90 from bucking to felling position. For this purpose, the lcarburetor is rotatably mounted between the intake manifold i2 vand the air intake assembly I1.

One end of the intake manifold iii has a flange 52 by means of which the manifold is bolted to the engine. The other end of `the manifold terminates in a circular portion S3 surrounded by an annular flange or shoulder '64 which is spaced from the end of the circular portion' and pro`I vides a seat for a rubber ring 65 which is shown as 'being of substantially square cross-section. The term rubber is herein used to include natural or synthetic rubber-like compositions. An extension collar 65 which is :bol-ted to the flanged end of the carburetor mixture outlet 56 surrounds the circular end portion 63 of the intake manifold and seats against the rub-ber ring S5, which provides a cushioned "bearing for the carburetor.

'At the opposite side, the carburetor `is supported in a similar manner by la rear bracket assembly comprising the air intake and rear handle. The air intake assembly l1 includes an air filter unit EIS having a hollow cylindrical casing (it which is open at both end-s land ya cylindrical filter unit 'It 4mounted inside the `casing with an annular air passage 'Il .between the casing and the filter. Air enters the inside of the filter from both ends and flows through the ii'lter into the annular passage 1|. A rotatable and reciprocable brush 12 is lprovided for cleaning the inside of the filter.

The assembly is mounted on the chassis by a bracket portion 73 which is preferably integral with the filter casing and is secured to the chassis by two bolts 'ist (Fig. 5). A tubular air passageway l5, which is shown integral with the bracket, projects laterally from the filter casing t9 and terminates in an integral sleeve bearing portion le which is open at both ends. The axis of the bearing portion 76 extends in a fore and aft direction, substantially in alignment with the circular end portion '53 of the intake manifold, and is thus approximately perpendicular to the air passageway 15. A bushing Tl, preferably formed of a suitable bearing material such as bronze, nts inside the .sleeve portionl and a fixed indexing plate 'i8 is provided on the rear end face of the sleeve portion.

A swivel member 86 is rotatable inside the bearing bushing il and has an annular flange BI adjacent the indexing plate '13. An annular ample by a plurality of screws 83, bears on the front end face of the bearing bracket 16 and thus cooperates with the ange 8| to hold the swivel member 89 against axial movement. The swivel plate 82 and adjacent end face of the swivel member 8i) together form an annular recess to receive a rubber ring 85 which, as shown, is identical with ring 65 described above. The end of the air inlet passage d of the carburetor seats on the rubber ring 85 so that the carburetor is in eliect clamped between the two rubber rings 55 and 85. The length of the carburetor is slightly greater than the free distance between the rings so that the rings are under compression when the parts are assembled and provide a cushion support protecting the carburetor' from jars and vibration.

The swivel plate 82 has forwardly projecting cup-shaped ears 86 which loosely embrace correspondingly shaped protuberances 8l provided on opposite sides of the'air inlet passage 54 of the carburetor. These ears cause the swivel member and carburetor to turn together and also prevent radial displacement :of the adjacent end of the carburetor.

The bearing bushing Tl has a radial opening aligned with the air passageway i5 and the swivel member @il has a passageway 88 comprising an axially extending portion Bao communi eating with the air inlet of the carburetor and a radially extending portion 88h communicating with the passageway 'i5 so as to provide a continuous air passage from the annular space 1| surrounding the iilter element it through the passageway 15 and the pass-age 83 of the swivel member 8:'3 to the carburetor. The radial portion 88h of the passage 88 in lthe swivel member Sil is of suiiicient circumferential extent to permit this member to rotate 96 without cutting off the air iiow to the carburetor, being like passage 233 of the swivel member 285 shown in Fig.

The swivel member 88 provides a rotatable support for a rear handle 9i) which constitutes one of the handles for holding and manipulating the saw. The rear handle is approximately D-shaped comprising two arms El and 92 which curve rearwardly and away from one another and a horizontal tubular handgrip portion $33 extending across between the rear ends of the arms. The swivel member, arms and hand grip are preferably integral with one another. The left arm 9i is longer than the right so that the grip is offset relative to the sleeve bearing l5 and is approximately centered with the center or" gravity lof the saw. The arms 9i S2 also preferably curve or slope upwardly so that the hand grip 'S3 is higher than the axis of the sleeve bearing TG. The rear handle normally remains with the grip portion 93 approximately horizontal at all times. This is a natural position for the operator so that strain and fatigue are minimized. When the saw is changed from bucking to felling position, the swivel member 80 which carries the rear handle turns in the sleeve bearing 'i6 or, more accurately, the saw, including the chassis, engine, fuel tank, cutting chain and support and air intake assembly, is turned 9S while the rear handle remains in its normal horizontal position. The carburetor, by reason of its connection with the swivel member 8|), also remains in its normal position and is thus kept right side up. Hence, merely by continuing to hold the rear handle in a natural manner as the saw is turned, the operator in eiect holds the carburetor against turning and keeps it upright. The rotatable mounting of the carburetor permits the relative rotation between the carburetor and the intake manifold I8 which is fixed with respect to the engine.

A latch member (Fig. 4) pivotally mounted on a rearwardly extending portion of the swivel member 8U is adapted to engage notches in the indexing plate 'i8 to hold the swivel member Sii against rotation relative to the sleeve bearing portion 'I6 of the air intake assembly. A springpressed plunger 95 presses upwardly on the rear end of the latc-h to hold the latch in locked position. The indexing plate 'I8 normally has two notches, one for felling position and the other for bucking position, although more can be provided if desired. The latch 94 is released by pressure vof the operators thumb on the rear end portion of the latch member which is suitably shaped for this purpose and is sumciently near the hand grip 93 so that the operator can release the latch without removing his hand from the grip.

A throttle control of novel construction is also associated with the rear handle. A plunger 96 is slidable in the tubular hand grip portion 93 against the action of a spring 91 and projects beyond the end of the hand grip. The plunger is held against rotation by a stud 98 Working in a slot 99 of such length as to limit the longitudinal movement of the plunger. A small bell crank lever lil@ (Fig. 6) is pivoted at on la supporting portion |92 which projects forwardly from the hand grip. One arm of the bell crank is rounded at its end and extends through a slot in the hand grip and into a notch |03 in the plunger S6. The other arm is connected by a wire or rod |E-l to the throttle control arm |05 (Fig. 3) of the carburetor The projecting end of the plunger 9B is partially surrounded by a protecting guard |66. A guard |01 on the hand grip S3 protects the bell crank |00 and also serves as a nger rest to prevent the operators hand from slipping on the grip. By pressing in on the plunger 9B against the action of spring 91, the operator rotates the bell crank in a clockwise direction and pulls on the connecting wire |04 to open the throttle. In order to hold the throttle open, particularly when starting the engine, the throttle control is provided with a latch which is shown in the form of a plunger |08 (Fig. 4) which is slidable in a hole through the supporting portion m2 on which the bell crank is mounted. When the latch plunger m8 is pushed up-after the throttle control plunger has been pushed in-the end of the latch plunger engages the bell crank |00 to hold it in open-throttle position. The plunger is preferably provided with a notch or abutment which engages the bell crank arm to hold the plunger in locking position. A light spring |09 tends to push the latch plunger downwardly so that it can be released merely by pushing in farther on the throttle control plunger 9S to disengage the bell crank from the latch plunger,

The rear bracket assembly also includes a rear foot It! (Figs. 2, 3 and 5) which is approximately L-shaped and, Ias viewed from the rear, projects downwardly and then to the right from the forward end of the air lter casing 69 and associated bracket portion i3. The foot is to the rear of the center of gravity of the saw and the horizontal portion ||2, which is adapted to rest on the ground when the saw is set down, extends transversely of the saw and is approximately centered with respect to a line extending directly rearwardly from the center of gravity. Y

With the construction described above, the entire rear bracket assembly, including the air intake and filter, rear handle and rear foot, is removable merely by removing the two bolts lll. This also releases the carburetor which is held between the air intake assembly and the intake manifold. Assembly and disassembly of the saw is thus extremely simple.

The saw is provided with a front handle im comprising a tubular member which is attached to the chassis at one end by bolts II and has an upwardly extending portion I IB, a top handle portion I Il which extends across above the front portion of the fuel tank and is substantially horizontal, a side handle portion IIS (Fig. 2) which extends downwardly on the left hand side of the iiy wheel housing when the saw is in bucking position and a front foot portion H9 which extends across underneath the saw and is attached to the chassis Iat its right hand end by one or more bolts I2 (Fig. 3). The top handle portion II'I curves smoothly into the side handle portion IIB so that the operators hand can slide from one portion to the other without impediment. The top handle portion l I'I and the major portion of the side handle IIB lie approximately in a vertical plane passing through the center of gravity of the saw. With this arrangement, the saw can be held or carried by the front handle alone without tipping objectionably. The lower portion of the side handle IIB extends forwardly, as seen in Fig. 2, so that the front foot portion Ile is located substantially in front of the center of gravity of the saw. As the front foot portion is a continuation of the side handle portion H8 and is of greater length than the width of the saw, the front foot, in conjunction with the rear foot i I I described above, provides a rm and stable support for the saw when it is set on the ground.

The arrangement of the front handle H4 and rear handle 9B greatly facilitates the handling and manipulation of the saw. The operators hands are at all times -in a natural and unstrained position. When the saw is in the bucking position illustrated in the drawings, it is held by the top handle portion ill and the rear handle 9B which are both substantially horizontal and parallel to one another. The saw can be tilted forward or back by raising or lowering one hand or the other. To tilt the saw sideways, the operator can shift his hand in one direction or the other along the top handle portion iI'i so that the weight of the saw tilts it naturally. In the felling position, the saw is held by the side handle portion IIS and rear handle Sii which has been turned relative to the chassis so that it is still horizontal `and now substantially parallel to the side handle portion H8. The operators hands are thus in the same natural position during both bucking and felling.

A lubricating oil tank 122 is mounted on the right hand side of the fuel tank i4 and is curved to conform to the curved upper surface of the fuel tank, The lubricating oil tank has a ller cap 23 and also an opening to receive a pump assembly I2i which is mounted on a cover plate i245 for the opening. The cover plate is removably held in place by a plurality of screws ii. The pump has a spring-pressed operating plunger #2l which projects upwardly from the cover plate in proximity to the front handle H4. A flexible tube |28 connects with the discharge outlet |29 of the pump and extends to a passageway leading to the sprocket wheel for driving the cutting chain 3. Downward pressure on the plunger IZ'I forces a small quant-ity of oil through the tube IES and connecting passageways to the driving sprocket from which it is thrown by centrifugal force on to the cutting chain. The location of the plunger |21 makes it possible for the operator to supply lubricant to the chain without removing his hand from the handle.

The operation of the saw is extremely simple and will be readily understood from the foregoing description. With the saw resting on the front foot I i9 and rear foot III, the engine is started by means of the starting handle Iii. During the cranking of the engine, the choke valve 53 is normally closed and the throttle is held open by lthe latch plunger |08. When the engine has been started, the choke valve is opened and the latch I is released. Engine speed is controlled by the operators right thumb pressing on the throttle control plunger 96.

If the saw is to be used in the bucking position, it is picked up by the rear handle 9G and top handle portion lI'l of the front handle II4. With the saw held in proper position to begin a out, the operator speeds up the engine by pushing in on throttle control plunger 9S with his right thumb. When a predetermined engine speed is attained, the automatic clutch engages to drive the cutting chain and the operator proceeds with the out. By causing the teeth I3 to engage the log and then lifting up on the rear handle, the operator can swing the chain support down about the teeth I3 as a fulcrum and thereby feed the cutting chain into the wood. It will be noted that the operators hands remain in a natural position, no twisting or other unnatural movement being required to control the throttle. When the out has been completed, the operator releases the throttle plunger 9E, whereupon the engine slows down to idling speed and the automatic clutch disengages the cutting chain from the engine.

When it is desired to use the saw in felling position, the operator releases the latch 9d by pressing down on it with his thumb without removing his hand from the rear handle. He then turns the saw by means of the front handle, for example by sliding his right hand along the handle from the tcp portion AI Il to the side handle portion I i8 while continuing to hold the rear handle in the same position. When the saw has been turned the latch 94 engages in another notch in the indexing plate le to lock the rear handle with respect to the chassis of the saw. The operators hands are in the same natural position during the felling operation as during bucking and the sequence of operations in making a cut is substantially the same as described above.

The novel construction and arrangement of the fuel system as described above assures uniform supply of fuel to the engine not only in normal bucking and felling positions of the saw but also when the saw is tilted at a substantial angle, for example an angle of 30 from the normal positions. Moreover, the simple operation of turning the saw from one position to the other as described above automatically turns the carburetor relative to the saw so that the carburetor remains right side up at all times.

Another embodiment of the invention is shown in Figs. '7, 8 and 9. Except for the differences shown in-the drawings and pointed out below, this embodiment is essentially the same as thatillustrated in Figs. 1 to 6 and corresponding parts are designated by the same reference numerals with the addition of 200.

The chain saw shown in Figs. '1, 8 and 9 has a chassis 201 on which is mounted a chain support 202 for the cutting chain 203. A one-cylinder engine 204 having a cylinder 205 and spark plug 206 is mounted with its cylinder inclined, preferably at about 45 to the horizontal (Fig. 7). The crank shaft of the engine carries a fly wheel and fan enclosed in a housing 209 and a cabletype starter having a starting handle 210 (Fig. 9) Power is transmitted from the engine to the cutting chain by a transmission enclosed in a housing 212 with which is associated a series of points 213 adapted to engage the Work and act as fulcrum for the saw.

The fuel system comprises a fuel tank 2i4, a carburetor 215 connected to the tank by ilexible tubing 216, an air intake assembly 211 and an intake manifold 218. The fuel tank 214 comprises an upper main chamber 220 and a lower auxiliary chamber 221. The tank has

side walls

222 and 223, an arcuate outer or upper wall 224 and a lower Wall 225 comprising an inclined portion 223 which overlies the engine, a downwardly extending portion 221 and a rearwardly extending portion 228. The two

chambers

220 and 221 are partially separated by a partition or baille 230 but communicate with one another through an opening 231 between the left hand end of the partition 230 and the left hand wall 222 of the fuel tank (Fig. 8). The lower chamber 221 is divided by a partition or baffle 232 into two

compartments

233 and 234 which communicate with one another through an opening 235 between the rear edge of the partition 232 and the outer wall 224 of the fuel tank (Fig. 7) The fuel tank has an outlet opening 236 provided with a suitable shut-off valve and connected by the flexible tubing 216 to the carburetor. A lling opening 231 is surrounded by a downwardly projecting skirt 238 and provided with a removable liquid-tight and airtight iiller cap 239. The venting system is similar to that described above and comprises vent cups 241 and 242 having vent holes 243 and 244, respectively. A vent tube 245 extends rearwardly and towards the left from the vent cup 241 and terminates at 246 near the vent cup 242. A second vent tube 241 extends upwardly, forwardly and to the right from the vent cup 242 and terminates at 24S adjacent the vent cup 241.

The carburetor 215, including an extension collar 236, is rotatably supported between an annular shoulder 234 on the intake manifold 213 and an axially aligned bearing portion of the air intake assembly 211, as described above. The air intake assembly 211 includes a filter unit 238 having a cylindrical casing 269 and a cylindrical filter unit 210 mounted inside the casing with an annular air passage 211 between the casing and the filter. The inner surface of the filter is cleaned by a rotatable and reciprocabl@ brush 212. The assembly is mounted on a chassis by means of a bracket portion 213 and bolts 214. An air passageway 215 leads from the annular space 211 to the interior of a sleevebearing portion 216 which is open at both ends and in axial alignment with the annular shoulder 264 of the intake manifold. A bearing bushing 211 lits inside the sleeve portion 213 and a fixed indexing plate 218 is provided on the rear end face of the sleeve portion.

A swivel member 280 is rotatable inside the bearing bushing 211 and has an annular flange 281 engaging the indexing plate 218. An ann nular swivel lplate 282 which is secured to the forward end of member 280 bears on the front end of the bearing portion 215 and thus co operates with flange 281 to hold the swivel 230 against axial movement. The carburetor iS mounted between -this swivel member 283 and the aligned end portion of intake manifold 218 by means of rubber rings, as described above. Cup-shaped ears 286 on the swivel plate 282 loosely embrace corresponding protuberances on the carburetor to hold the carburetor against radial displacement and to cause it to turn with the swivel member. A passageway 283 in the swivel member 280 provides communication for the flow of air from the passageway 215 of the lter to the carburetor.

The rotatable member 280 carries a rear handle 230 comprising upwardly curved arm por tions 232 and a tubular handgrip por-tion 293 extending across between the rear ends of the arms. A spring-pressed latch member 29a engages notches in the indexing plate 218 to hold the swivel member 280, and hence the rear handle, in selected posi-tion. The rear handle carries a spring-pressed throttle control plunger 256 connected by suitable means with the throttle control arm 305 of the carburetor, as described above, so that the operator can control the carburetor by thumb pressure on the plunger 236 without removing his hand from. or changing his grip on, the rear handle portion 293.

The air intake assembly is also provided with a rear foot portion 31| which projects downwardly from the bearing portion 216 and has a horizontal portion 312 extending transversely of the saw.

The saw has a front handle 314 comprising a tubular member attached to the chassis at one end by bolts 315 and having an upwardly extending portion 316, top handle portion 311, side handle portion 318 and a front foot portion 319 which extends across beneath the saw and is attached to the chassis at its right hand end. The saw is preferably provided with a chain lubricating system like that described in conjunction with the embodiment of Figs. 1 to 6. To simplify the drawings, this lubricating system has been omitted from Figs. 7, 8 and 9.

The arrangement and shape of the parts shown in Figs. 7, 8 and 9 provide still greater conipactness and lighter weight. The operation of the saw is essentially the same as described above in connection with Figs. 1 to 6.

While the invention has been described with particular reference yto the preferred embodiments illustrated in the drawings, it will be un derstood that the novel features of the invention are applicable to other embodiments and in n0 way limited to the specific constructions herein shown and described. Moreover, while best re suits are attained by the cooperation of al1 of the novel features shown and described, it will be understood that certain of the features may, if desired, be used separately from others. Moreover, the several features of the chain saw shown in Figs. rI to 9 may be interchanged with those of the saw Shown in Figs. 1 to 6. References in the foregoing description to left and right are used for convenience in describing the particular constructions shown in the drawings and are not to be construed to limit the invention. While the angularity of the fuel tank shown in Fig. 'I is not as great as that 13 shown in Fig. 4, the upper and lower portions of the tank being disposed at an obtuse angle to one another, the term substantially L- shaped as herein used is understood to coinprise both embodiments as well as similar arrangements.

What we claim and desire to secure by Letters Patent is:

l. In a chain saw driven by an internal combustion engine, the combination of a fuel tank which is substantially L-shaped in vertical longitudinal section, comprising a horizontal portion and a downwardly projecting portion at one end of said horizontal portion, an intake manifold and an air intake passage below the fuel tank, a carburetor swivelly mounted between the intake manifold and the air intake passage, a lexible connection from the carburetor to the downwardly projecting portion of the L-shaped fuel tank and a pair of handles comprising -a fixed front handle and a swivelly mounted rear handle connected with the carburetor, whereby rotation of the rear handle rotates the carburetor.

2. In a chain saw driven by an internal combustion engine and having a frame and saw chain support, the combination of a fuel tank which is substantially L-shaped in vertical foreand-aft section comprising a horizontal portion and a downwardly projecting portion at the rear end of the horizontal portion, an intake manifold and an air intake passage below the fuel tank and in Xed position relative to the frame, a carburetor swivelly mounted between the in take manifold and the air intake passage, a iiexible fuel conduit connecting the carburetor with the downwardly projecting portion of the fuel tank and a handle swivelly mounted on the air intake passage and connected with the carburetor, whereby the carburetor turns with the handle.

3. In a chain saw driven by an internal combustion engine and having a frame and a saw chain support in fixed relation to the frame, the combination of a fuel tank which is substantially arcuate in vertical longitudinal section comprising a portion disposed above the engine and a downwardly projecting portion at the rear of the engine, an intake manifold and an air intake passage mounted below the fuel tank in fixed relation to the frame and having axially aligned openings, a carburetor swivelly mounted in said openings, a flexible conduit connecting the carburetor with the downwardly projecting portion of the fuel tank and a saw supporting handle swivelly mounted on the air intake passage to turn about the axis of said openings, said handle being connected with the carburetor, whereby the carburetor turns with the handle relative to the frame.

4.-. In a chain saw driven by an internal combustion engine and having a chassis and a saw chain support fixed relative to the frame, the combination o1" a fuel tank which nts over the engine and is substantially L-shaped in vertical longitudinal section comprising an approximately semicircular upper wall and a lower wall having a horizontal portion joining the upper wall at one end, a downwardly extending portion at the opposite end of the horizontal portion and a second horizontal portion joining the lower end of the downwardly extending portion and the opposite end of the upper wall to form a downwardly extending portion of the tank, a carburetor swvelly mounted on the chassis below the 1,4 fuel tank, a flexible .fuel conduit connecting the carburetor with the `downwardly extending portion of the fuel tank and a saw supporting handle swivelly mounted on the chassis and connected with .the carburetor, whereby the carburetor turns with the handle relative to the chassis.

5. In a chain saw driven by an internal combus-tion engine and having a ,chassis and a vsaw chain support in fixed relation to the chassis, the combination of a fuel tank which is substantially Lshafped in vertical longitudinal section comprising a horizontal portion above the engine and a downwardly projecting portion, a baille partially separating said portions of the tank but leaving an opening between them adjacent one side Vof the tank, a carburetor .swivelly mounted on the chassis below the fuel tank, a exible conduit connecting the carburetor with the downwardly projecting pontion of the fuel tank, and a saw supporting handle swivelly supported on the chassis and connected with the carburetor, whereby the carburetor turns with the handle.

6. In a chain saw driven by an internal combustion engine and having a chassis, the combination of a fuel tank which is substantially arcuate in vertical longitudinal section comprising an upper portion overlying the engine and a lower portion projecting downwardly at the rear of the engine, a bale substantially separating said portions of the tank and leaving an opening between them only at one side of the tank, a second baille dividing said lower portion into a larger chamber at the side adjacent said opening and a smaller chamber at the opposite side of the tank, said chambers being connected by an opening adjacent the outside rear wall of the tank, a carburetor swivelly mounted on the chassis below the fuel tank, a ilexible conduit connecting the carburetor with the bottom of said smaller chamber, and a saw supporting handle swivelly supported on the chassis and connected with the carburetor, whereby the carburetor turns with the handle.

7. In a chain saw driven by an internal cornbustion engine and having a chassis, the combination of a fuel tank which ts over the engine and is substantially L-shaped in vertical longitudinal section comprising an arcuate upper wall and a lower wall tting over the engine and providing an upper main chamber and a downwardly projecting lower chamber, a pair of vent storage cups provided on the upper wall, one of said cups being located on the forward upper portion or" said wall adjacent one side of the tank and the other being located on the rearward upper portion of said wall adjacent the opposite side of the tank, a vent opening connecting each of the cups to the atmosphere, a vent tube connected with each of the cups and opening on the inside of the tank adjacent the other cup of the pair, a carburetor swivelly mounted on the chassis below the fuel tank, a fuel line connecting the carburetor with the lower chamber of the fuel tank, and a saw supporting handle swivelly supportedv on the chassis and connected with the carburetor. whereby the carburetor turns with the handle.

8. In a chain saw driven by an internal cornbustion engine and having a chassis, the combination of a fuel tank which is substantially L- shaped in vertical section comprising an upper chamber overlying the engine and a downwardly projecting lower chamber, an intake manifold having a circular opening, an air intake passage having an opening in axial alignment with that of the intake manifold, a rubber ring surrounding each of said openings, a carburetor disposed between said rubber rings, means for securing the air intake passage to the chassis to clamp the carburetor between said rubber rings and resiliently support it for rotation about the axis of said holes, a fuel line connecting the carburetor with the lower chamber of the fuel tank and a saw supporting handle swively supported by the air intake passage to turn about said axis and connected with the carburetor, whereby the carburetor turns with the handle.

9. In a chain saw driven by an internal combustion engine and having a chassis, the combination of a fuel tank mounted over the engine, an intake manifold having an opening, an air intake unit comprising an air lter and an air passage terminating in a cylindrical bearing in axial alignment with the opening of the intake manifold, means for securing the air intake unit to the chassis, a carburetor swivelly supported between said cylindrical bearing and the opening of the intake manifold, a fuel line connecting the carburetor with the fuel tank, a handle support rotatable in said cylindrical bearing, a saw supporting handle carried by said support and means connecting the handle support with the carburetor, whereby the carburetor turns with the handle support and handle.

10. In `a chain saw driven by an internal combustion engine and having a chassis, the combination of a fuel tank mounted over the engine, an intake manifold having an opening below the fuel tank, a bearing fixedly supported on the chassis in alignment with said opening, a carburetor swivelly supported between the bearing and the opening, a fuel line connecting the carburetor with the fuel tank, a handle support rotatable in said bearing, said support extending rearwardly and upwardly from said bearing and terminating in a bifurcated portion, a handle extending across between the ends of the bifurcated portion of the support and means connecting the handle support with the carburetor, whereby the carburetor turns with the handle support and handle.

1l. In a chain saw driven by an internal combusti-on engine and having a chassis, the combination of a fuel tank mounted over the engine, an intake manifold having an opening below the fuel tank, a bearing iixedly supported on the chassis in alignment with said opening, a carburetor swivelly supported between the bearing and the opening, a fuel line connecting the carburetor with the fuel tank, a handle support rota-t able in said bearing, a saw supporting handle carried by said support, means connecting the handle support with the carburetor whereby the carburetor turns with the handle support and handle and a latch for releasably holding the handle and carburetor in any of a plurality of predetermined positions.

12. In a chain saw driven by an internal combustion engine and having a chassis, the combination of a fuel tank mounted over the engine, an intake manifold having an opening below the fuel tank, a bearing xedly supported on the chassis in alignment with said opening, a carburetor swvelly supp-orted between the bearing and opening and having a throttle, a handle support rotatable in said bearing, said support extending rearwardly from the bearing and terminating in a bifuroated portion, a handle extending across between the ends of the bifurcated portion of the handle support, a throttle control member movably mounted at lone end of the handle, being CTI movable in a direction lengthwise of the handle, connections between the control member and the throttle and means connecting the handle support with the carburetor, whereby the carburetor turns with the handle suppont and handle.

i3. In a chain saw di'iven by an internal combustion engine and having a chassis and a carburetor, the combination of a fuel tank which is substantially L-shaped in vertical fore-and-aft section comprising an upper chamber and a lower chamber communicating with the upper chamber adjacent the left hand side of the tank as viewed from the rear with the saw in bucking position, an intake manifold having a rearwardly facing opening below the fuel tank, a bearing fixedly supported on the chassis directly to the rear of and in alignment with said opening, a fuel line connecting the carburetor` with the lower right hand portion of the lower chamber of the fuel tank, a substantially rectangular front handle comprising a tubular member secured at one end to the upper right hand side of the chassis, and extending upwardly, across the top of the chassis, downwardly on the left hand side of the chassis, across below the chassis and secured at the other end to the lower right hand side of the chassis, the upper .and left hand portions of the handle being approximately in a vertical plane passing through the center of gravity of the saw while the lower portion is forward of said plane, a rear handle support rotatable in said bearing, a rear handle carried by said support and having a hand grip portion which is approximately parallel with the upper portion of the front handle when the saw is in buck-ing position andby rotation of said rear handle supportis approximately parallel with the left hand portion of the front handle when the saw is in felling position and means connecting the rear handle support with the carburetor whereby the carburetor turns with the rear handle and is in upright position in both of said positions of the saw.

14. In a chain saw driven by an internal combustion engine and having a chassis, the combination of a fuel tank mounted over the engine, an intake manifold having a rearwardly facing opening below the fuel tank, a bearing fixedly supported on the chassis directly to the rear of and in alignment with said opening, a carburetor swivelly supported between the bearing and the opening, a fuel line connecting the carburetor with the fuel tan-k, a front handle comprising a tubular member secured at its ends to the chassis and having a top portion extending across above the chassis when the saw is in bucking position, a side portion at approximately right angles to the top portion and a foot portion below the chassis and approximately parallel tc lthe top portions, the top portion and side portion being approximately in a vertical plane passing through the center of gravity of the saw Iwhile the foot portion is forward of said plane, a rear handle rotatably supported by said bearing and having a hand grip portion which is approximately parallel with the top portion of the front handle when the saw is in bucking position and-by rotation of the rear handle in said bearing--is approximately parallel with the side portion 4of the front handle when the saw is in felling position and means connecting the rear handle with the carburetor whereby the carburetor turns with the rear handle and is in upright position in both of said positions of the saw.

l5. IIn a chain saw driven by an internal comf bus-tion engine having a carburetor, said chain 11 Saw havn-1s a chassis atri a saw Chain. support in fixed relation to the chassis@ fueltahk which is substantially L-sliaped inyertioal longitudinal Section and comprises en epass Cha-mbsf overlying the engine aafla lower auxiliary @hamber separated from the upper chamber by a wall with an opening connecting the two chambers adjacent one side of the tank, a fuel outlet located at the bottom of the lower chamber at the opposite side of the tank, lthe carburetor being disposed below the fuel tank vand on the same side as said outlet, and a fuel line' connecting the carburetor with said outlet of the fuel tank.

16. In a chain saw driven by internal combustion engine having a carburetor, said chain saw having a chassis'and a saw chain support rigidly fixed to the chassis, a fuel tank which is substantially L-shaped in vertical section and comprises an upper main chamber overlying the engine, a lower auxiliary chamber projecting downwardly from the main chamber, a baiiie separating the two vchambers except for an Opening adjacent one side o f the lfuel tank and a second baffle disposed at approximately right angles to the rst and dividing the lower chamber linto a larger compartment communicating through said opening with the upper chamber and a smaller compartment out of direct communication with the upper chamber butl communicating with the larger compartment through `Ian openarises-4i ing adjacent the outside wall of the fuel tank, an

outlet located at the bottom of the smaller compartment of the lower chamber in spaced relation to the opening connecting the smaller compartment with the larger compartment, the carburetor being disposed below the fuel tank and on the same side as said outlet and a fuel line connecting the carburetor with said outlet of the fuel tank.

17. In a chain saw driven by an internal cornbustion engine having a carburetor, a fuel tank comprising side walls, an approximately semicircular outer wal1 joined at its side edges to the side walls, a stepped bottom wall joined at its side edges to the side walls and its ends to the outer wall, the bottom wall having an upper level cooperating with the side walls and outer wall to form an upper fuel chamber and a downwardly extending portion cooperating with the side walls and outer wall to form a lower fuel chamber, and a partition partially separating said chambers but with an opening connecting them adjacent one of the side walls, the carburetor being disposed below the fuel tank and at the side opposite said opening and a fuel line connecting the carburetor with the lower portion of the lower chamber on the same side as the carburetor.

18. In a chain saw driven by an internal combustion engine having a carburetor, an L-shaped fuel tank comprising side walls, an approximately semicircular outer wall, a stepped bottom wall having an upper fuel chamber and a downwardly projecting portion cooperating with the side walls and outer wall to form a lower fuel chamber, a partition separating the said chambers except for an opening between them adjacent one of the side walls and a second partition which is approximately perpendicular to said first partition and divides the lower chamber into a larger compartment at the side adjacent said opening and a smaller compartment at the opposite side of the tank, said compartments being connected by an opening adjacent the outside wall of the tank, a fuel outlet located at the. bottom of the smaller. compartment. and spaced from the last mentioned opening. the carburetor being disposed below the fuel'tank and onthe same side as saidoutletanda fuel line connecting Saidoutlet with the carburetor.

19- Ina chain 'S2W drivenbr an internal 00H1.` bustion engine having acarhuretonauu-shapeu fuel tank comprisns sidewalls', an "approximately semicircular gouter wall anda stepped bottom walha'pair of vent cups provided on the outer wall',one ofthe cups being located on the fr'ward upper part'of'sad 'outer walladia-ent one ofthe sidewalls'iand' the'other of the cups beinglopate'don the 4rearward upper portion of saidouter Wall'djaceht the' yOlJDSite"side wall, a vent Opening connecting achbf'saiii cups with the atmosph'ere,4 t tube for each of said cups, each tube heme c ted atoneend to itsrlspective cup' and" having 'thev otherend openk t0 the interior of the tank adjacent'the vother cup of the pair, the ,carburetor being disposed below the 4fuel .tank and la fuel line vco Iinenting thev carburetor with the 'fuel tank.'

20. In a chain' saw driven by an internal combustion `engine' 'and having" a `chassis and a' saw chain [supportv xed'elati'veto rthe' chassis, the combination'bf an L-shaped fuel tank ,comprising side `walls, 'an "approximately ,semijciircular outer wall, a s'tepped'bottonjwallhaving 'an upper levelfcoop ingwf'th" the' sidewalls and outer wall to' f rm an Tupper'fuel' chamber and a downwardly extending'portion cooperating with the side walls and outer wall to form a lower fuel chamber below and at the rear of the upper chamber, a partition separating said chambers except for an opening between them adjacent the left hand side wall of the tank as viewed from the rear of the saw, and a second partition which is approximately perpendicular to the rst mentioned partition and divided the lower chamber into a larger compartment at the side adjacent said opening and a smaller compartment at the opposite side of the tank, said compartments communicating with one Aanother through an opening adjacent the rear portion of the outer wall, a fuel outlet located at the bottom of the smaller compartment and spaced from the last mentioned opening, a fuel inlet opening at the top of the tank, an airtight closure for said inlet opening, a vent cup provided on the upper forward portion of the tank adjacent the right hand side wall, a second vent cup provided on the upper rearward portion of the tank adjacent the left hand side wall, a vent opening connecting each of said cups with the atmosphere, a vent tube for each of said cups, each tube being connected at one end to its respective cup and having the other end open to the interior of the tank adjacent the other cup, an intake manifold having an opening below the fuel tank and on the same side as said fuel outlet, an air intake unit comprising an air filter and an air passage opening at one end into the air lter and provided at the other end with a cylindrical bearing portion disposed directly to the rear of and in axial alignment with the opening of the intake manifold, a carburetor swivelly supported between said bearing and the opening of the intake manifold, :a fuel line connecting the carburetor with the outlet of the fuel tank, a front handle comprising a tubular member secured at its ends to the right hand portion of the chassis and having a top portion extending across above the chassis when the saw is in bucking position, a left side portion at approximately right angles to .the top portion and a foot portion below the chassis and approximately parallel to the top portion, the top portion and left side portion being approximately in a Vertical plane passing through the center of gravity of the saw while the foot portion is forward of said plane, a rear foot portion projecting downwardly from said air intake unit, a rear handle rotatably supported by the cylindrical bearing portion of the air intake passage and having a hand grip portion which is approximately parallel with the top portion of the front handle when the saw is in bucking positionby rotation of the rear handle in said bearing-is approximately parallel with the side portion of the iront handle when the saw is in felling position, and means connecting the rear handle with the carburetor whereby the carburetor turns with the rear handle and is in upright position in both of said positions of the saw.

21. In a chain saw driven by an internal combustion engine and having a chassis, a saw chain support in fixed relation to the chassis, a fuel tank mounted in fixed relation to the chassis, a saw-supporting handle iixedly mounted on the chassis, a second saw-supporting handle rotata` bly mounted on the chassis for rotation about an approximately horizontal axis, a. carburetor rotatably mounted on the chassis for rotation duits connecting the carburetor with the fuel tank and the engine, said conduits permitting at least limited rotation of the carburetor relai-1 tive to the chassis, and connections between the carburetor and said rotatable saw-supporting about an approximately horizontal axis, fluid conhandle, whereby the carburetor turns with the handle relative to the chassis.

JOHN A. ABBOTT.

GEORGE H. BARBER.

ALBERT K. NEWMAN.

LILLIAN K. SCHINDLER, Administratrice of the estate of Charles F. Schindler, deceased.

REFERENCES CITED The following references are of record in the file oi this patent:

UNITED STATES PATENTS Number Name Date 1,234,482 Loury July 24, 1917 1,717,547 Bens June 18, 1929 2,051,195 Arsneau Aug. 18, 1936 2,068,787 Baumgartner Jan. 26, 1937 2,133,458 Lesage Oct. 18, 1938 2,256,831 Karey Sept. 23, 1941 FOREIGN PATENTS Number Country Date 553,744 Germany June 30, 1932 676,377 Germany June 3, 1939