US2396583A - Pruner or like tool - Google Patents

Description

March 12, 1946. K ETAL 2,396,583

PRUNER OR LIKE TOOL Original Filed May l7 1944- BY i b i AT TZR/VEKQ Patented Mar. 12, 1946 UNITED STATES PATENT OFFICE 2,396,583

PRUNEB R LIKE TOOL Kurt H. Lenk, Bridgeport, Conn., and.Dwight E. Priest, Southboro, Mass, assignors to Parker Manufacturing Company, Worcester, Mass, a corporation of Massachusetts Original application 535,942. Dividedan 1945, Serial No. 587,572

4 Claims. This invention relates to pruning shears and like hand tools comprising crossed pivoted levers,

and the object is to provide an improved latching arrangement for holding the levers in closed position (ordinarily against the action of a spring which tends to open them as herein illustrated) with the end of providing a neat and sturdy too], easy of operation and free of projecting parts which might possibly hurt the hand or be fouled by exterior objects, as, for example, when working a pruner among thickly set twigs.

This application is. a division of our application Serial No. 535.942, filed May 17, 1944, wherein other features, herein more or less incompletely disclosed, are more fully described and claimed.

Our invention will be well understood by reference to the following description taken in connection with the accompanying drawing, wherem:

Fig. 1 is a side elevation of a pruner illustrative of the invention;

Fig. 2 is a similar view showing the pruner open;

Figs. 3 and 4 are sections on an enlarged scale on the correspondingly numbered lines of Figs. 1 and 2 respectively;

Figs. 5 and 6 are sections on the correspondingly numbered lines of Fig. 1; and

Fig. 7 is a section on the line 'l7 of Fig. 1 on an enlarged scale.

In the drawing we disclose as an example of a crossed-lever tool to which our improvements are applicable a pair of pruning shears of the anvil type and in particular one using a separate steel blade. The details of construction are more fully disclosed in our parent application of which this is a division, and for the present purposes it is sufficient to state that the tool shown comprises two levers l2 and M, which may conveniently be die castings of soft but strong material, such as a suitable alloy of aluminum or magnesium, crossed and joined by a pivot pin It. The lever l2 is formed with a depressed seat to receive the steel blade 22 which is supported substantially in the plane of the joint between the levers. The levers l2 and [4 are spring pressed to open position, herein by means of a coiled torsion spring 49 which has convolutions received in an annular chamber 34 organized around the pivot pin it and formed by suitable depressions in the opposed faces of the tool levers at the location of the joint, the spring having tangential ends which project beyond the plane of the helical body due to the pitch of the widening and which lie neatly in extensions 38 and 30 from said with parts broken away May 1-7, 1944, Serial No. this application April 10,

chamber in the inner faces of the levers. respectively. The spring is tensioned in the closed position of the tool illustrated in Fig. 1 and tends.

tion which opposes an edge portion 460i the, a joint concentric with the.

lever M to provide pivotal axis of the tool. The circular edge portion 46 is formed with an undercut recess 50 which substantially closed position of Fig. 1, it. aligns with a recess 0r groove. 38 in the shoulder 44. in whichis. houseda catch 52 which may be projected'therefrom across the joint to engage recess 50.

near the outer end of recess 48 and in the re.-

tracted position of Fig. 6 clearsthe joint with its.v left-hand side viewing Fig. 4 resting on the bot-. The right-hand portion of, this tom thereof. catch is shaped to enter the recess 50 when the catch is rocked to the position of Fig. 3 and may terminate in a short shoulder 53 which engages the upper edge of shoulder 46 where the latter forms the boundary of the recess. To the left of this shoulder is a roughened thumb-engaging portion providing a shallow, generally lenticular projection beyond the face of the tool and which is desirably of such length that in either position (Fig. 3 or Fig. 4) it substantially fills the top of groove 48. Means may be provided for exerting a spring tension on the catch to prevent accidental movement. We have here shown (see Fig. 7) a helical spring 54 engaging the side of the catch, the spring 54 conveniently encircling the pivot pin and being received in the relatively large hole from one side of the recess 48 in which opening it is retained by the enlarged head. 56 of the pin which fits the opening. The parts can thus be readily assembled by inserting the spring and pin from the right in the figure.

With the parts in the position shown in Fig. 1 and the hand grasping the handle levers in the usual manner, the thumb of the grasping hand can be extended to engage the exposed portion of the catch 52 which is preferably knurled as indicated and, the tension of the spring being somewhat relaxed by slight grasping pressure of the hand, a downward wiping movement of the thumb will rock the catch to the inactive position of Figs. 2 and 4, placing the tool in conopens to the joint, but does not intersect, the face of the lever and, with the tool in the,

The catch 52 is pivotedeccentrically.

dition for use. When it is desired to lock the 2. In a tool of the pivoted, crossed lever type parts, the tool is closed and an outward wiping which is normally biassed to open position, one motion of the thumb will return the catch to the lever having a shoulder portion which opposes position of Figs. 1 and 3. Release of the grasp an edge portion ofthe other to provide a joint, of the hand causes the spring to tend to rotate 5 a recess in the shoulder opening to the joint, a lever l4 counterclockwise so that the left-hand recess in the edge portion aligning with the first end of the recess 50, viewing Fig. 1, binds against in a substantially closed position of the tool, one the side of the catch 52, holding it firmly in the of said recesses being undercut, a catch pivoted engaged position. The catch seats in groove near the outer end of the other recess and havin 48 in the open position of Fig. 4 without tendlo 'a nose portion which swings across the joint and ency to swing therefrom until it is again enenters the undercut recess and a rounded progaged by the operator and it is effectually shieldjecting thumb-engaging portion rearwardly ed by the operator's hand from contacts with therefrom exposed at the face of the tool and exterior objects tending to displace it upwardly of such length as substantially to fill the top of and to locking position from the position of Fig. said other recess in all positions of the catch.

2. The construction is sightly as the recess 50 3. In a tool of the pivoted, crossed lever type is concealed and the recess 48 substantially diswhich is normally biassed to open position, one simulated at all times by the catch received lever having a shoulder portion which opposes an therein. There are no openings to pinch the edge portion of the other to provide a joint, a fingers or to catch twigs or the like. 2 recess in the shoulder opening to the joint, a re- We are aware that the invention may be emcess in the edge portion aligning with the first bodied in other specific forms without departing in a substantially closed position of the tool; one from the spirit or essential attributes thereof, and of said recesses being undercut, and a catch in we therefore desire the present embodiment to the other recess capable of being housed therein be considered in all respects as illustrative and or projected across the joint to engage in the unnot restrictive, as is in fact clear in several matdercut recess. ters from the description itself. Reference is to 4. In a tool of the pivoted, crossed lever type be had. to the appended claims to indicate those which is normally biassed to open position, one

principles of the invention exemplified by the lever having a shoulder portion which opposes particular embodiment described and which we an edge portion of the other to provide a joint, desire to secure by Letters Patent. a recess in the shoulder opening to the joint, a

We claim: recess in the edge portion aligning with the first '1. In a tool of the pivoted, crossed lever type in a substantially closed position of the tool, a which is normally biassed to open position, one catch adapted alternatively to lie retracted in lever having a shoulder portion which opposes one recess or to beprojected across the joint to an edge portion of the other to provide a joint, engage in the other, holes of different diameters a recess in the shoulder opening to the joint, a intersecting the walls of the first recess, a spring recess in the edge portion aligning with the first received in the larger hole to bear on the catch, in a substantially closed position of the tool, one and a retaining pin in said holes traversing the of said recesses being undercut, a catch pivoted 40 catch to retain it movably in its recess, the pin near the outer end of the other recess and having having a head fitting the larger hole and retaina nose portion which swings across the joint and ing the spring therein. enters the undercut recess and a rounded pro- KURT H. LENK, jecting thumb-engaging portion rearwardly DWIGHT E. PRIEST.

therefrom exposed at the face of the tool. 46

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