US2253440A - Hacksaw - Google Patents

Description

Aug. 19, 1941,

P. E. MARTIN v HACKSAW 1 EMa/rZz'n I Ia Filed Nov. 28, 1938 mjm ATTORNEVS WITNESS Patented Aug. 19, 1941 UNITED STATES PATlillJT OFFICE HACKSAW Paul E. Martin, N ewgulf, Tex. Application November 28, 1938, Serial N 0. 242,850

2 Claims.

This invention relates to hack saws, and its general object is to provide a hack saw in which the blade can be applied and removed, as well as adjusted at various angles, with respect to the frame, in an easy and expeditious manner and with minimum effort on the part of the user, and the adjustment can be made almost instantly without removing the blade from the frame or possibility of casual removal therefrom, in that the blade mounting stems are constantly held under tension.

A further object is to provide a hack saw of the character set forth, that includes a frame which is adjustable for receiving blades of various lengths, and the saw is simple in construction, inexpensive to manufacture, and extremely efiicient in operation, use and service.

This invention also consists in certain other features of construction and in the combination and arrangement of the several parts, to be hereinafter fully described, illustrated in the accompanying drawing and specifically pointed out in the appended claims.

In describing the invention in detail, reference will be had to the accompanying drawing wherein like characters denote like or corresponding parts throughout the several views, and in which:

Figure 1 is a side elevation of the saw which forms the subject matter of the present inven-.

tion.

Figure 2 is a sectional view taken approximately on line 2-2 of Figure 1, looking in the direction of the arrows.

Figure 3 is a sectional view taken approximately on line 3-3 of Figure 2, looking in the direction of the arrows.

Figure 4 is a sectional view taken approximately on line 4-4 of Figure 2, looking in the direction of the arrows.

Figure 5 is an end view of the sleeve for the adjusting means at the rear or handled end of the saw.

Figure 6 is an end view looking toward the inner end of the front adjusting means, with the blade removed.

Referring to the drawing in detail, it will be noted that the frame of my saw in the form as shown, is of the sectional type and includes rear and front end sections l and 2 respectively and a channeled intermediate section 3 riveted or otherwise secured to the front end section 2, with the rear end section mounted for slidable movement therein for adjustment of the end sections relative to each other, as will be apparent upon inspection of Figure 1. The intermediate section terminates at its outer end into rounded spaced parallel ears 4 having a pin 5 secured to and bridging the same, to be received in any one of the notches l disposed along the inner edge of the rear end section, for holding the sections secured in adjusted positions. By that construction, it will be obvious that the frame is adjustable for receiving blades of various lengths.

Secured to the rear end section by rivets or the like is a shank 8 of a handle 9 of the arouate pistol grip type, as shown.

The end sections are curved in the usual manner to provide parallel portions having formed on the outer ends thereof barrels Ill and II respectively, disposed in alignment with each other, and having annular flanges formed on theinner or confronting ends thereof, while their outer ends are com letely open, as Well as provided'with notches I2 and I3 disposed in companion pairs for a purpose which will be presentlydescribed.

Mounted in the barrel l0 and being of a length to extend beyond the ends thereof is a saw blade stem I4 threaded for the major portion of its length with the threaded portion I5 provided with opposed flat faces. The inner end of the stem I4 is reduced and has a saw blade receiving stud l6 secured thereto for disposal laterally thereof, as shown. Slidably mounted on the threaded'portion is a headed collar I! having a shank provided with a parallel sided oval shaped bore, as best shown in Figure 5, for fitting association of the parallel sides, with the flat faces, to,

prevent rotation of the collar relative to the stem l4, as will be apparent, and sleeved upon the stem I4 is a coil spring l8 that has its end convolutions engaging the flange of the barrel and the inner end of the shank respectively, for urging the collar outwardly of the barrel. Secured to the shank are lugs I9 in the form of pins extending from diametrically opposite sides thereof to be received in either pair of notches l2 and which are held therein by a wing nut 20 threaded on the portion l5, as shown in Figures 1 and 2.

Mounted in the barrel II is a saw blade stem 2| that likewise has a reduced inner end, with a stud 22 secured thereto for cooperation with the stud l 6 for detachably securing the saw blade to the stems, and fixed to the outer end of the stem 2! by a pin 23 is the shank of a headed collar 24, the pin being of a length to extend upon opposite sides of the shank of the collar 24 to be received in either pair of notches l3. Sleeved on the stem 2| is a coil spring 25 haw'ng its end convolutions engaging the flange of the barrel II and the inner end of the collar 24,

as clearly shown in Figure 2, for urging the collar 24 outwardly of the barrel II.

From the above description and disclosure of the drawing, it will be obvious that the collars l1 and 24 are slidably and rotatably mounted within their barrels and are urged outwardly therefrom by the coil springs, and when it is desired to change the angle of the blade 26 with respect to the frame, such as for instance from the position shown to a position at right angles thereto, the wing nut 20 is loosened to allow removal of the lugs l9 and pin 23 from the notches shown, thence the blade can be rotated for disposal of the lugs I9 and pin 23 in the other set or pair of notches and held accordingly by tightening the wing nut. In order to facilitate the adjustment of the blade to its respective positions, I provide a finger lever 2'! bent adjacent one end to form a shank portion and a handle, and the shank portion is preferably frictionally mounted in a bore extending transversely through the stem 2|, as best shown in Figure 1. It will be further obvious that inasmuch as the stems are under constant tension, especially due to the fact that the collar is fixed to the stem 2|, that casual removal of the blade from its studs is practically impossible during the adjustment.

It is thought from the foregoing description that the advantages and novel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claims.

What I claim is:

1. A hack saw comprising a frame having sleeve-like barrels forming bearings in alignment and secured to the ends of the frame, inside stops in said bearings, collars fitted into the outer ends of the bearings, said collars and said outer ends of the bearings being formed with clutches whereby they may be interengaged to prevent turning of the collars in the bearings, stems fitted through said collars and extending inwardly beyond the barrels, one of said stems being secured to its collar and the other stem being slidable through its collar and externally threaded, coil springs enclosed within the barrels and interposed between the corresponding to disengage said clutches to permit simultaneous rotation of the stems, a saw detachably secured at its respective ends to the inner ends of said stems, a nut threaded onto the threaded stem and adjustable thereon into abutting relation with the outer end of the corresponding collar to maintain it clutched with the corresponding barrel and operative through the stems and saw to maintain the other collar clutched with its barrel and to maintain the springs under compression, said nut being adjustable to released position to permit simultaneous expansion of the springs and simultaneous disengagement of the clutches without releasing the tension of the springs on the blade whereby the stems and blade may be turned about the axis of the stems to any selected point of adjustment.

2. A hack saw comprising a frame having sleeve-like barrels in alignment and forming bearings secured to the ends of the frame, inside stops in the bearings, collars fitted into the outer ends of the bearings, coil springs between the stops and the inner ends of the collars, heads on the outer ends of the collars, said heads and the outer ends of the barrels being formed with clutch means whereby they may be interengaged to prevent turning movement of the collars in the bearings, stems fitted through said collars and extended inwardly beyond the barrels, one of said stems being secured to its collar and the other stem being slidable through its collar and externally threaded'and operatively connected with its collar for turning movement therewith, a saw detachably secured at its respective ends to the inner ends of the stems, a nut threaded onto said threaded stem and adjustable thereon into abutting relation with the adjacent head to maintain said adjacent head clutched with the corresponding barrel and also operative through the stems and saw to maintain the other head clutched with its barrel and to maintain the springs under compression, said nut being adjustable to released position to permit simultaneous expansion of the springs and simultaneous disengagement of both clutch means, said .springs when expanded maintaining tension on the saw to prevent disengagement of the saw with said stems, said stems and blade being turnable, upon release of the clutch means, about the axis of the stems to any selected point of 5'6 adjustment. stops and collars, said springs normally tending PAUL E. MARTIN.

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