Патент USA US2021736код для вставки
Nov. 19, 1935. F. MAY PRUNING DEVICE Filed Dec. 10, 1954 I 2,021,736 Patented Nov. 19, 1935 2,021,736 A UNITED STATES PATENT OFFICE 2,021,736 PRUNING DEVICE ' Friedrich May, Magdeburg, Germany Application December 10, 1934, Serial No. 756,762 In Germany August 30, 1933 4 Claims. (CI. 30—11) branches by means of knives connected with one tween this lever and the lever I2 is effected by means of a saw-blade l8 ,so'that the implement another and operated by the intermediary of can be used also for sawing purposes. This invention relates to a device for pruning levers subjected in one direction to the action 5 of springs by means of which they are moved back, together with the knives, into their posi tion of rest. My present improved pruning de vice is distinguished from the known devices for the purpose in view by the characterizing fea 10 tures that one of the two ?at knives, or knife blades respectively, forming parts of the imple ment and being shiftable relatively to one an other is coupled with a one-armed lever, where as the other blade is coupled with a double-armed 15 lever, preferably in such a manner that the blades can be adjusted at said levers. Designing the pruning device in this manner renders it possible to manufacture it on the whole-sale scale at a low price, and further ad 20 vantages are that this improved device is very reliable in service and operates unobjectionably and without jamming even if the blades are not held exactly at right angles with respect to the branches to be lopped-off. 25 In a preferred constructional form of this de vice the two levers mentioned are connected with one another by a serrated bar, or a saw blade respectively, may be in connection with a spring actuated member able to take up the recoils. 30 The invention is illustrated diagrammatically and by way of example on the accompanying drawing which shows a side-view of a pruning device designed according to this invention. On the drawing, I and 2 are the two knife 3 blades which are arranged above one another and of which I is shiftable between guide members 3 and 4 forming parts of a rigid frame 5, where as the blade 2 is shiftable between said guide member and a guide member 1 having a guide 40 groove 6 and being preferably detachably at tached to said frame 5. The blade 1 is coupled with a one-armed lever l2 fulcrumed at H to the guide member 3. In said lever is a slot l0 and in said blade is a slot 8, and a bolt 9 though 45 both slots can be adjusted in the slot 8 and secured therein after the adjustment. The bolt slides in the slot 5E3 when the lever I2 is moved up and down in order to actuate the blade I. Likewise the blade 2 is coupled with a double-armed lever ' 50 ll fulcrumed at iii to the frame 5; it has a slot l3 and said lever has a slot l5, and a bolt l4 ex tends through both these slots. The bolt I4 can be adjusted and ?xed in its adjusted position in 55 the same manner as the bolt 9 which will be clear without a more detailed explanation. The two blades can be moved simultaneously, counter to one another, by means of a rope 20 or the like. In the preferred constructional form shown by way of example, the rope 20 terminates already at the lever I1 and the connection be Drawing the levers back into their position of rest can be effected, for instance, either by means 5 of a helical tensile spring 2| engaging the lever l2 or by means of a helical tensile spring 22 en gaging the lever l‘! or by both these springs, as in the drawing. It is suited to the sawing purpose to insert between the blade l8 and the lever 12 a 10 rec-oil device H), as in the ?gure shown. 23 and 24 are abutment members for the two levers, and 2'1 is a wooden rod, to the upper end of which the implement is attached. The lower portion of this latter is tubular, as at 26, and 15 receives in it the correspondingly shaped upper end of said rod. Below the guide member I the frame 5 is provided with a hook 25 serving for tearing down branches that have not been com pletely severed off by the knife blades. 20 I claim: 1. A branch pruning device, comprising, in com bination, two oppositely located knife blades mov able in opposite directions, means guiding said blades, a one-armed lever coupled with one of the 25 blades and a double-armed lever coupled with the other blade, means for moving said levers with the blades back into their original position, and means for operating the said levers and the said blades. 30 2. A branch pruning device, comprising, in com bination, two oppositely located knife blades mov able in opposite directions and subjected to the action of springs adapted to move them into their original position, means guiding said blades, a 35 one-armed lever coupled with one of said blades and a double-armed lever coupled with the other blade, and means for actuating said levers to gether with the said blades. , 3. A branch pruning device, comprising, in com~ 4O bination, two knife blades arranged oppositely to one another, guide members for said blades, 2. one armed lever coupled with one of said blades and a double-armed lever coupled with the other blade, a saw-blade connecting the two levers with one 45 another at their free ends, a pulling member at tached to one of said levers; and means adapted to counter-act said pulling member. 4. A branch pruning device, comprising, in com bination, a frame having pairs of guides located 50 one above the other, knife blades shiftable in said guides in opposite directions, a one-armed lever fulcrumed in said frame and coupled with one of said blades, a double-armed lever likewise ful crumed in said frame and coupled with the other 55 blade, springs adapted to move said levers back into their initial position, and means for operat ing the said levers with the blades from below. FRIEDRICH MAY.