US2525235A - Handsaw - Google Patents

Description

H. MYERS HANDSAW Get. 10, 1950 Filed Dec. 24, 1947 Patented st. 10, 1950 2.525.235 I naunsaw Hugh Myers, London, England Application December 24. 1947, Serial No. 793,738 In Great Britain Becember 2, 1946 Section 1, Publiclbaw 690, August 8, 1946 Patentexpires December 2, 1966 7 1 Claim. 1

This invention relates to hand saws and has particular reference to a known form of keyhole or pad saw in which a blade of hacksaw type is provided along its back edge with a reciprocatory support which is slidably mounted in a member adapted to be gripped by hand to which handling member the blade is clamped, so that as the handling member is thrust forward to cause the saw blade to cut the work, the reciprocatory support whilst still pressing down on the back edge of the blade is pressed back by its contact with the work against the resistance of a spring which is anchored at one end to the handling member and at the other end to the reciprocatory support.

In the above connection it has been proposed to provide a keyhole or pad saw of the character specified in which the handle was of pistol grip shape and surmounted by a comparative short body which Was made integral with the handle grip and provided with a longitudinal tunnel for slidably supporting the reciprocatory blade support, the rear of which latter projects through said tunnel and has its extremity at all times located at the rear of the back end of the tunnelled body. Above and parallel to the tunnel the handle is provided with a housing to the front end of which the front end of a tension spring is anchored, Whilst the rear end of the spring is attached to the rearwardly extending extremity of the reciprocatory blade support. Whenthe blade support is situated at the forward end of its stroke, the collapsed tension spring is accommodated entirely within said spring housing. As the reciprocatory support moves rearwardly the rear portion of the extending spring is drawn out of the housing and is uncovered. This may prove to be dangerous in the event of spring breakage.

The object of the present invention is to provide a hand keyhole or pad saw of the same general form as that described but which incorporates some important novel constructional features, so that at no time is the control spring of the reciprocatory blade support uncovered and further the hand grip of the saw ma be adjusted in relation to the plane in which the blade saw reciprocates.

In accordance with the'present invention the body of the saw incorporates an elongated tubular housing in which the reciprocatory blade support is slidably mounted and which encloses at all times the control spring for the reciprocatory blade support. Preferably the control spring is of compression type and is disposed within the housing substantially in axial alignment with the reciprocatory blade support. The housing may be and preferably is made of sufficient length to accommodate all except the front end portion of the blade support when said support has receded into the housing. Further a hand grip is associated with the tubular housing and may be mounted in such a manner as to permit of its adjustment in relation to the tubular housing. Primarily this adjustment is for the purpose of altering the position of the hand grip by longitudinal movement, but may also be such as to alter the angular disposition of the hand grip in relation to the plane in which the saw blade reciprocates.

A preferred embodiment of the present invention is illustrated in the accompanying drawings, wherein:

Fig. 1 is aside elevation,

Fig. 2 is a longitudinal sectional elevation, and

Fig. 3 is an enlarged cross-section on line IIIIII of Fig. 1.

In the form illustrated the body of the saw comprises an elongated tubular housing i of circular cross section at the forward end of which is mounted a head member 2 which combines the functions of guiding the reciprocatory blade support 3 and of temporarily clamping in fixed relation to the housing i the rear end of a hacksaw type blade 4. A handle is mounted on the housing I and this handle consists of a hand grip portion 5 surmounted by a split sleeve portion 6 within which said tubular housing I is adapted to be received and clamped. Alternativel or additionally a hand gripping portion may be provided on the housing I itself, for example, by fitting a rubber sheath thereover, such as used on the handlebars of bicycles. The guide portion of the head member 2 consists of a bore 1 having a diameter to receive snugly and slidably the rodlike reciprocatory support 3 for the clamped blade 4. The clamping of the blade 4 is effected by passing the rear end thereof into a narrow longitudinal slot 8 which opens into the guiding bore 1 and screwing one or more binding screws 9 in tapped holes ill in the wall of the head member 2 into contact with one side of the blade 4. The bottom of the slot 8 is widened by undercutting to form a channel ll wide enough to accommodate freely the laterally splayed teeth 4a of the blade 4. The back edge db of the blade 5 is received within a narrow longitudinal groove l2 provided in the underside of the reciprocatory blade support 3. The forward end 3a of the reciprocatory blade support 3 is of larger diameter than the stem of the support 3 and has a pair of oppositely disposed flats 3b. This fiat-sided end 3a carries an abutment member l3 which is preferably detachably mounted on the end 3a, being secured by a clamping screw I4. The abutment member I3 is adapted to come into contact with the face of the work to be sawnand thus afford a backing support for the blade 4 as near as possible to the point of sawing. The abutment member I3 is preferably provided as shown, with a freely revoluble grooved roller I5 which bears upon the back edge of the blade 4.

The rear end of the tubular housing I is closed by a plug I6 against which the rear end of a coiled compression spring I! presses. The front end of the spring I? presses against a plug I8, which as shown can bear upon the rear end of the head member 2, or alternatively against a washer, pin or equivalent abutment provided at'the rear extremity of the rod-like blade support 3. The extent of the forward movement of the blade support may be limited by the use of a stop element which, as shown in Fig. 2, may be in the form of a small pin I9 projecting above the blade support 3 and adapted to contact with the inner face of a recess at the rear end of the head member 2. The blade support 3 may be swung over (when no blade is clamped to the head member 2) to align the stop pin I9 with the slot 8 in which the blade 4 is normally clamped and thus permit of entire disengagement of the blade support 3 from the housing I and head member 2. The provision of the stop pin I9 is not essential, however, as the rear end I2a of the groove I2 in the blade support 3 serves to prevent removal of the support 3 when a blade 4 is clamped in the head member 2.

The split sleeve 6 of the handle is provided with a pinching screw 2| for drawing together two lugs 6a of the sleeve 6 for the purpose of gripping the tubular housing I within the handle sleeve 6.

I claim:

A saw of the class described, comprising, in combination, an elongated tubular housing closed at its rear end; a head member fixed to the front end of the housing and including a'tubular portion having an internal bore and an integral radially offset portion provided with a slot communicating with said bore and adapted to receive and accommodate a blade, said head member also having a threaded hole disposed at right angles to the blade receiving portion of the slot and also provided at its rear end with a reduced portion telescopically fitting into the said housing, said portion being provided with a recess whose wall includes a continuation of said slot, a blade clamping screw in said threaded hole, a blade support slidably mounted in said bore of the tubular portion of the head, said support having a groove extending from the underside to the axis thereof and registering with said slot of the radially offset portion, said groove having a curved rear end blade abutment portion, a pin projecting laterally from the inner end of the blade support and insertible through the slot of the radially offset portion into the recess to be rotated for engagement with the inner edge of the recess to detachably lock the blade support in the head, a work abutment member detachably mounted upon the front end of the blade support and having a roller mounted therein, a blade fitting in the groove of said blade support and having its rear end fitting in said slot to be engaged by said screw, and a coil spring fitted in said housing and confined between the closed end thereof and a shouldered abutment plug which engages the end of the recessed portion of said head member.

HUGH MYERS.

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

UNITED STATES PATENTS Number Name Date 405,540 Driuer June 18, 1889 488,844 Smith Dec. 27, 1892 1,779,857 Shafer Oct. 28, 1930 2,137,742 Jack Nov. 22, 1930 FOREIGN PATENTS Number Country Date 512,611 Great Britain Sept. 21, 1939

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