Handsaw

Abstract

A relatively economical and simply constructed handsaw is comprised of a one piece molded holder and a flexible saw blade firmly retained therein. The holder has a handle portion with a longitudinally extending passageway in which a portion of the blade is slidably seated, and a relatively rigid support portion extending from one end thereof and providing support for the blade at a point spaced from the handle portion. The external configuration of the handle portion is complex and is shaped to provide a secure and comfortable grip during use.

Description

BACKGROUND OF THE INVENTION

Various types of handsaws have been devised and are widely employed for cutting applications, and these saws may have different constructions depending upon the intended application and the cutting blade to be used therein. For example, hacksaws customarily employ a frame to support the thin flexible blade at a point spaced forwardly of the handle. Cross-cut and rip saws generally rely upon a tapered blade of relatively great width to provide the desired strength and resistance to excessive bending but only secure that blade at the handle. There have been many efforts to devise simple and relatively low cost constructions for handsaws which would facilitate the interchangeability of blades and which would provide means for simple engagement of such blades while permitting the use of the tool for various cutting applications.

In making tools for the home market, there has been a growing trend to simplified and more economical construction; unfortunately, this has often been at the expense of good gripping or handling characteristics or at the expense of durability. Since the sawing action requires a good grip upon the tool, it is extremely desirable that any tool be so configured as to provide a comfortable and secure grip for the user. Moreover, if the number of component parts is reduced, it should not be at the expense of durability and proper support for the blade.

Accordingly, it is the primary object of the present invention to provide a novel handsaw including an integrally formed, one piece holder molded from a synthetic resinous material and affording a comfortable and secure grip during use.

It is also an object of the invention to provide a handsaw of the foregoing type in which the support portion of the holder is configured to provide a relatively large clearance area over the portion of the blade extending thereacross, while at the same time providing firm support therefor.

Another object is to provide such a handsaw having clamping means on the support portion which is of simple design and yet highly effective.

Still another object of the invention is to provide such a handsaw wherein the passageway through the handle portion is especially configured to permit facile insertion of the saw blade thereinto while at the same time limiting twisting and other undesirable movement of the blade about its longitudinal axis within the holder.

A still further object of the invention is to provide such a handsaw having the foregoing features and advantages, which in addition employs relatively few and simple components, and which may be produced in a relatively facile and economical manner.

SUMMARY OF THE INVENTION

It has now been found that the foregoing and related objects of the present invention may be readily attained in a handsaw comprising a relatively thin and flexible elongated saw blade and a molded, one piece holder that is integrally formed from a synthetic resinous material. The holder comprises a handle portion having a longitudinal passageway, in which a portion of the saw blade is slidably seated, and a rigid support portion of generally inverted U-shaped configuration. The support portion extends from one end of the handle portion, and has its free end providing support for the blade at a point spaced from the handle portion. The handsaw also includes means on the free end of the support portion disengageably clamping the blade in a fixed position within the handle. The handle portion is elongated, and it has a complex external configuration providing longitudinally extending ribs along the upper and lower side margins thereof and recessed side surface portions therebetween. The configuration of the handle portion affords a secure and comfortable grip on the handsaw during use.

In the preferred embodiments of the invention, the generally inverted U-shaped support portion of the handsaw has an elongated center arm spaced above the plane of the upper surface of the handle portion, to provide an elongated clearance area above the blade. Preferably, a stepped surface is provided on one side of the leg of the support portion that provides the free end thereof, and the leg has an aperture extending therethrough. The stepped surface is adjacent the free end and provides a shoulder that extends in the direction of the longitudinal axis of the holder and that is of a depth substantially equivalent to the thickness of the blade. The clamping means may include a fastener extending through the aperture in the leg and a clamping plate seated on the surface thereof and on the blade. The fastener draws the clamping plate tightly against the blade, and the blade thereby against the surface of the leg, to clamp the blade tightly therebetween. Most desirably, the stepped surface of the leg providing the free end has a double-stepped configuration providing a second shoulder spaced inwardly from the first shoulder. The clamping plate is seated on the step provoding the second shoulder, the latter being of a depth substantially equal to the thickness of the clamping plate to provide a substantially flush side surface. Advantageously, the clamping plate is internally threaded and cooperates with an externally threaded bolt to provide a fastener, and ideally the aperture is present adjacent the first mentioned shoulder. In such a case, the fastener extends below the shoulder with the blade bearing against the shank thereof.

Generally, the blade of the handsaw will be of substantially uniform width along its entire length and the passageway to the handle portion will be dimensioned and configured to enable facile insertion and sliding movement of the blade thereinto. To restrict sidewise and rotational movement of the blade within the passageway, the passageway beneficially has a portion of reduced cross-sectional area snugly seating the blade. In preferred embodiments, the reduced portion of the passageway extends inwardly from the "one" end of the handle portion and the passageway has a portion of greater cross-sectional area extending inwardly from the opposite end thereof. The passageway of such embodiments is dimensioned and configured to provide a trans-sectional portion blending the reduced and greater cross-sectional area portions and providing guide surfaces to facilitate insertion of the blade into the passageway from the opposite end of the handle portion. Most desirably, the reduced cross-sectional area portion of the passageway includes generally U-shaped channels snugly seating the upper and lower edges of the blade, and the greater cross-sectional area portion thereof is of generally octagonal configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a handsaw enbodying the present invention;

FIG. 2 is a side elevational view of the handsaw of FIG. 1 drawn to a slightly diminished scale and showing, in phantom line, the blade in an extended position;

FIG. 3 is a front end elevational view of the handsaw drawn to a slightly enlarged scale from that of FIG. 1;

FIG. 4 is a fragmentary exploded perspective view of the front end of the support portion of the holder and a portion of the blade that is supported thereby;

FIG. 5 is a fragmentary side elevational view of the front end of the assembled handsaw, with nut plate omitted for clarity of illustration;

FIG. 6 is a sectional view of the handsaw along line 6 -- 6 of FIG. 2 and drawn to an enlarged scale.

FIG. 7 is a sectional view of the handsaw along line 7 -- 7 of FIG. 2 and drawn to the same scale as FIG. 6; and

FIG. 8 is a perspective view of a section along line 6 -- 6 of FIG. 2, drawn to a still further enlarged scale and with the blade removed to illustrate the configuration of the passageway through the holder thereat.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

Turning now in detail to the appended drawing, therein illustrated is a handsaw embodying the present invention and including a one-piece holder, generally designated by the numeral 10, which is molded from a synthetic resinous material. Mounted within the holder 10 is a hacksaw blade, generally designated by the numeral 12, which is of conventional thin, flexible construction and has a width dimension "a" that is uniform along its entire length.

The elongated handle portion 14 of the holder 10 has a complex external configuration providing longitudinally extending rib elements 16 along the lower side margins thereof, and recessed side surface portions 18 that diverge upwardly and blend to an enlarged upper surface portion 20 providing rib elements 21 thereat. This configuration of the handle portion 14 renders the saw comfortable to hold and enables secure gripping thereof in the operative position; as will be noted, the handle portion 14 also has a complex curvilinear external configuration along its longitudinal axis, which further contributes to the comfort and security of the grip thereon. The eleptical apertures 22 that are centrally located within the surface portions 18 are caused by the use of stabilizing mold elements, and serve no necessary function in the tool herein described.

The holder 10 also includes a generally inverted U-shaped support portion, generally designated by the numeral 24, which consists of an elongated, generally rectilinear rigid arm 26 which extends along an axis generally parallel to the axis of the handle portion 14 and is offset a short lateral distance therefrom. One end of the arm 26 is spaced upwardly from and is attached to the adjacent end of the handle portion 14 by a short connecting leg 28, which blends into the contour of the handle portion 14. The leg 30 depending from the opposite end of the arm 26 to provide the free end of the support portion 24 affords overlying support for the blade 12 at a point spaced forwardly of the handle portion 14 and has means therein for securing the blade, as will be described hereinafter. The leg 28, the arm 26 and the leg 30 cooperatively define an elongated, generally U-shaped clearance area 32 extenxing above the portion of the blade 12 that projects from the passageway of the handle portion 14.

As can best be seen in FIG. 4, one side surface of the leg 30 has a double-stepped configuration provided by a first inside surface 40 extending upwardly from the free edge of the leg 30 to the shoulder 41 which extends in the direction of the longitudinal axis of the holder 10 and is of a depth substantially equal to the thickness of the blade 12. The double-stepped configuration also includes a second, shallower side surface 42 that extends from the first shoulder 41 to an angularly disposed shoulder 44, which rises to the plane of that side surface of the body of the leg 30. Centered on the shoulder 41, the leg 30 of the support portion 24 has a centrally located aperture 34 passing therethrough, in which is received the threaded shank 36 of the slotted thumbscrew 38. As will be apparent from FIGS. 3 and 5, the upper edge of the blade 12 bears upon the shank 36 of the thumbscrew 38.

The blade 12 is secured on the step 40 defined by the shoulder 41 by the nut plate 46 which seats the step 42 of the leg 30. The nut plate 46 has an angular edge which mates with the angular shoulder 44 of the leg 30. Tightening of the thumbscrew 38 creates a slight turning movement upon the nut plate 46, and produces a very tight and effective grip of the lower edge of the nut plate 46 upon the side surface of the saw blade 12 to clamp it firmly against the step 40.

Turning now in detail to FIGS. 6 - 8, therein is best illustrated the external configuration of the handle portion 14 and the configuration of the passageway defined therethrough. The cross sectional configuration at the forward section of the passageway shown in FIG. 6 is defined by narrow top and bottom U-shaped channels 48 defining a recess greater than the width of the blade 12, and a relatively wide center portion defined by side surfaces which are spaced apart a distance considerably greater than the thickness of the blade 12. Right anglular shoulders 52 extend from the side surfaces 50 to the channels 52. As can be appreciated, the blade 12 snugly seats on the channels 52 to restrict movement thereof about its longitudinal axis within the handle portion 14 either in a sidewise or in a twisting manner.

The rearward portion of the passageway that is depicted in FIG. 7 is generally octagonal in configuration and includes side surfaces 50 and top and bottom surfaces 48 that correspond to the bottom surfaces of the channels 48 seen in FIG. 6. However, the cross-sectional configuration of the relatively unrestricted portion of the passageway shown in FIG. 7 omits the inwardly disposed right angular shoulders 5 to define the channels 48 and instead has sloping surfaces 54. Beveled surfaces 56 (shown in FIG. 8) provide a gradual transition between the shoulders 52 and the sloping surfaces 54 and afford effective guides to facilitate insertion of the blade 12 from the rear of the handle portion 14.

As will be appreciated by those skilled in the art, the complex configuration of the passageway permits it to be formed using a mold element that consists of a relatively heavy base (of hexagonal cross-section) on which is supported a more delicate element having a configuration producing the compound rectangular shapes and the right angle shoulders 54 present in the restricted portion of the passageway. The use of such a mold element greatly facilitates the production of the holders herein employed and of the desirably configured passageway therethrough.

The holder may be molded of any of numerous different types of synthetic thermosetting and thermoplastic resins. Exemplary polymers include the polyolefins, such as polyethylene and polypropylene; the vinyl and vinylidene resins, such as polystyrene, polyvinyl chloride, impact polystryrene and the ABS-types of graft copolymers; filled polymers, such as the fiberglass reinforced polyesters; the long-chain synthetic polyamides, and many others.

The dimensions and external configuration of the holder will be chosen for optimum strength, gripping comfort and security, consistent with appropriateness for the particular type and size of saw blade employed. Although hacksaw blades, with which the present tool is particularly well adapted for use, may vary in length, a 10-inch long blade is typical and is particularly convenient in providing a variety of adjusted positions for different purposes. Thus, the cutting blade may be used at a point forwardly of the arm 30 as well as rearwardly thereof.

The particular means by which the blade is clamped may also vary considerably from that illustrated although that embodiment offers a particularly effective means of tightly securing the blade in a quick and convenient manner.

Thus, it can be seen that the present invention provides a novel handsaw including an integrally formed, one piece holder molded from a synthetic resinous material and affording a comfortable and secure grip during use. In the handsaw, the support portion of the holder is configured to provide a relatively large clearance area over the portion of the blade that extends thereacross, while also providing wholly adequate support therefor, and the clamping means on the support portion is of simple and yet highly effective design. The passageway through the handle portion may be specifically configured to permit facile insertion of the saw blade thereinto, while at the same time limiting twisting and other undesirable movement of the blade about its longitudinal axis within the holder. Moreover, the handsaw employs relatively few and simple components and may be produced in a relatively facile and economical manner.

Claims

Having thus described the invention, I claim:

1. A handsaw comprising a relatively thin and flexible elongated saw blade of substantially uniform thickness along its entire length; a molded one piece holder for said blade integrally formed from a synthetic resinous material and comprising a handle portion having a longitudinal passageway in which a portion of said blade is slidably seated and a rigid support portion of generally inverted U-shaped configuration extending from one end of said handle portion and providing a pair of depending legs and an elongated center arm with the leg at its free end providing support for said blade at a point spaced from said handle portion, said elongated center arm being spaced above said saw blade to provide an elongated clearance area above said blade; and means on said leg at said free end of said support portion disengageably clamping said blade in a fixed position within said holder, said handle portion being elongated with a complex external configuration providing longitudinally extending ribs along the upper and lower side margins and recessed side surface portions therebetween, said external configuration facilitating secure and comfortable gripping of said handsaw, said passageway through said handle portion being dimensioned and configured to enable facile insertion and sliding movement of said blade therethrough and said passageway having an elongated portion of reduced cross sectional area snugly seating said blade to restrict horizontal vertical and rotational movement of said blade in said passageway.

2. The handsaw of claim 1 wherein said elongated center arm is spaced above the plane of the upper surface of said handle portion.

3. The handsaw of claim 2 wherein said leg of said support portion providing said free end has a stepped surface on one side thereof adjacent said free end providing a shoulder extending in the direction of the longitudinal axis of said holder and of a depth substantially equivalent to the thickness of said blade, said leg having an aperture extending therethrough; and wherein said clamping means includes a fastener extending through said aperture in said leg and a clamping plate seated on the surface of said leg and of said blade, said fastener drawing said clamping plate tightly against said blade and said blade thereby against the surface of said leg to clamp said blade tightly therebetween.

4. The handsaw of claim 3 wherein the stepped surface of said leg providing said free end has a double-stepped configuration providing a second shoulder spaced inwardly from said first shoulder, said clamping plate being seated on the step providing said second shoulder, said second shoulder being of a depth substantially equal to the thickness of said clamping plate to provide a substantially flush side surface.

5. The handsaw of claim 3 wherein said clamping plate is internally threaded and cooperates with an externally threaded bolt to provide said fastener.

6. The handsaw of claim 3 wherein said aperture is adjacent said first mentioned shoulder and said fastener extends below said shoulder, said blade bearing against the shank of said fastener.

7. The handsaw of claim 1 wherein said reduced portion of said passageway extends inwardly from said one end of said handle portion, and wherein said passageway has a portion of greater cross-sectional area extending inwardly from the opposite end of said handle portion, said passageway being configured and dimensioned to provide a transectional portion blending said reduced and greater cross-sectional area portions thereof and providing guide surfaces to facilitate insertion of said blade into said passageway from said opposite end of said handle portion.

8. The handsaw of claim 7 wherein said reduced cross-sectional area portion of said passageway includes generally U-shaped channels snugly seating the upper and lower edges of said blade, and wherein said greater cross-sectional area portion thereof is of generally octagonal configuration.