US2613437A

US2613437A - Power-operated pivoted shears

Info

Publication number: US2613437A
Application number: US157986A
Authority: US
Inventors: William F Mcphee
Original assignee: IRVIN M SLEPICKA
Current assignee: IRVIN M SLEPICKA
Priority date: 1950-04-25
Filing date: 1950-04-25
Publication date: 1952-10-14
Anticipated expiration: 1969-10-14

Description

Oct. 14, 1952 4 w, F, MOPHEE 2,613,437

POWER-OPERATEDPIVOTED SHEARS Filed April 25, 1950 ,ii-s ggi mmvrom WILL/AM E- McPHEE v I-IM/ M ATT'Y Patented Oct. 14, 1952 2,613,437 POWER-OPERATED PIVOTED SHEARS William F. McPhee, Ringwood, 111.,

Irvin M. Slepicka, Chicago,

six-tenths to assignor of Ill.

Application April 25, 1950, Serial No. 157,986 2 Claims. (01. 30-228) This invention relates in general to a power cutter and is more particularly described as a portable hydraulic shears which includes a pressure cutter and a hydraulic means for applying pressure to the cutter.

An important object-of the invention is to provide a pressure operated clamping jaw type of cutter in which the applied pressure may be sustained or increased and applied as desired.

A further object of the invention is to provide a jaw type of cutter having means for starting the spread of the arms and then applying full pressure at the ends of the arms.

A further object of the invention is to provide a fluid pressure cutter in which the entire pressure is thrown upon a movable cross head attached to the pivotal point of the jaws.

A further object of the invention is to provide the jaws with a circular portion at a distance from the pivot for receiving the direct thrust of fluid pressure applied to the jaws.

A still further object of the invention is to provide a portable cutter of the hydraulic type having a fluid pressure hydraulic pump connected thereto for applying fluid under any desired pressure to the jaws.

Still a further object of the invention is to provide a portable hydraulic power cutter which may be readily moved and transported and made in different sizes for different classes of work.

Other objects of the invention will appear in the specification and will be apparent from the accompanying drawings in which,

Fig. l is a view partly in perspective showing a fluid pressure power cutter in accordance with this invention, and a fluid pressure pump for applying pressure to the cutter;

Fig. 2 is a sectional view showing the valve arrangement for the fluid pressure device;

Fig. 3 is a sectional view of the fluid pressure piston in connection with the cutter; and

Fig. 4 is a perspective view of the pivoted ends of the cutter jaws and showing the power applying connections thereto.

Although it is frequently desired to cut rods and cables on the. job at a distance from a machine shop, most of such Work is laboriously done by means of a hack saw, pipe cutters, and other tools which are neither designed nor intended for the particular purpose.

The present invention provides a powerful hand tool which may be easily carried wherever desired, the cutter jaws being strong and compactly made and having means for applying hydraulic pressure at th ends of the jaws where :2-

ill

2 it is most effective with an accompanying hand operated fluid pressure pump for applying a high operating pressure to the cutter.

Referring now more particularly to the drawings, a pair of jaw members H] are similar in shape and are adapted to be placed oppositely together to receive a pivoting bolt l2 through aligned holes l4 and each having a rounded surface It extending about the axis of the bolt at the inner sides of the members when they are placed together. At the outer ends of the members are jaws it which may have extremities 20 for producing a punching and shearing action with each other when they are moved together. Each jaw is formed with a recess 22 which may be used for clamping, securing and shearing action, but preferably a removable jaw member 24 is adapted to be seated in the recess for cooperating with the opposite jaw member when the jaws are moved together. Each jaw member 24 pref erably has a shouldered portion 26 for seating it in the recess 22 and a thinner portion 28overlapping the outer side of the jaw member 16 with a hole 30 therein for receiving a fastening screw 32 which extends into a threaded hole 34 in the jaw member at the edge of the recess 22. At the outer side is a beveled sharp cutting edge 34 with a central recess 36 sharp at the outer'edge forming a cutter for small rods, bars and cables inserted therein.

Attached to the outer ends of the pivot bolt l2 is a cross head 4!) having opposite -'perforated sides 42 each extending over one end of the bolt on opposite sidesof the members [0 and secured in place by nuts 44 threaded on the ends of the bolt I2. A bolt 4'6 has a head 68 inserted -be tween the inside of the cross-head 40 and bearing upon the curved surface 15 of the two jaw members. This bolt extends through the cross head and is threaded into a plunger extending radially inward between the jaw members. Surrounding the plunger is a cylinder 52 in which the plunger is movable and at the outer end of the plungeris a washer 5 1 which makes a'fluid tight connection with the inside of the cylinder. At the inner end of the cylinder is a projecting collar 56 secured to or formed integrally with the cylinder having opposite inclined surfaces 58 and having a projection Bil on one or both sides with a threaded perforation for receiving a bolt 62 extending therefrom parallel tothe cylinder.

The adjacent inner portion of each jaw member ID has an inside projection 6A with an inner inclined surface 66 adapted to be engaged by the inclined surface 58 of the collar when it is moved relatively outward between the jaw members in their collapsed position. Tending to return the jaws to their collapsed position is a spiral spring 59 disposed in the cylinder 52 abutting the closed end of the cylinder at one end of the spring and abutting the inner end of the plunger 50 or the exposed face of the washer 54 attached to the plunger.

Mounted for free sliding motion upon the outside of the cylinder is a collar 68 having a lateral projection 10 on one or opposite sides corresponding to the projection 60 (or projections) of the collar 56. The bolt 62 extends freely through a perforation in the projection I and is provided with a nut I2 at the outer end of thebolt to. limit the movement of the

collars

56 and 68 apart, but to allow them to move relatively together. At opposite sides of the collar 68 are projections 14 having pivot pins I6 extending ther-ethrough for receiving arms I8 pivoted therein, the outer end ofeach arm being connected by a pivot 80 with a pivoted bolt 82 attached through the outer end of the. jaw member I 0.

At, the outer end of the cylinder 52, a hollow sleeve 84 is inserted and adapted to receive an end.- fitting 86 of a pressure hose 88 threaded or attached, therein.

With this construction. fluid pressure applied to the inside of the cylinder 52 wil spread apart the: cylinder and the plunger 50. Since the plungeris rigidly attached by means ofthecross head tothe J'aw members with the head 48 of the fastening bolt bearing upon the jaw members,

the plunger is held firmly but the cylinder is forced. outwardly and if the jaw members have been: collapsed or moved tightly together, the collar- 56,: at the inner end of the cylinder will engage its inclined surfaces 58. with the inclined surfaces 6601 the jaw member projection 64 first moving; the jaw'members angularly apart..

Since there is a slight lost motion between the

collars

56 and 68, the collar 68- is not moved outwardly on the cylinder until the lost motion on the bolts: 62 is taken up and the collar 58 bears against the outer or adjacent end of the collar 68.. When the cylinder 52 has been moved to this extent, pressure is then applied by the cylinder to the collar 68 forcing the arms 78 outwardly. At this time, the jaws have been moved outwardly so that the pressure against the arms 18 is at a greater angle. to the adjacent inner surfaces of the jaw members and is held. nearly normal to theendsoi the jaw membersv which is the position where the jaws are actually the closest together.-

A suitable pump for applying fluid pressure comprises. a short pipe 90 to one endof which the free end of the hose 88 is attached. At the other endof the pipe 90 are fittings 92 connecting it with a cylinder 94 for supplying fluid under pressure: to the pipe. At the top of the cylinder is a cap- 96 and extending through the cap is a stem 98 of a plunger I00 in the cylinder. At the cylinder end of the pipe is a ball valve I02 having a seat I 04 and at the other end of the pipe is a ball valve I06 having a seat I08. The ball valve I02 is held in place by a spring H0 and the ball valve I06 is-held in place by a spring I I I. I

Extending upwardly from the middle of the pipe is a plunger cylinder II2 havin a plunger II4 movable therein by means of the stem I I6. The stem extends through a fitting I I8 at the top of the cylinder II2 where it is connected by a stirrup fitting I20 intermediate the ends of a handle I22. The. adjacent end of the handle is y by operating the handle I22, or

connected by a stirrup fitting I24 with an upright post I26 fixed to a base I28 to which the pipe 90 is also attached by means of a strap I30.

At the discharging end of the pipe 90 between the ball I06 and the end of the pipe is a shut off valve comprising a hollow valve mounting I32 connected through the pipe 90 and having a valve I 34 engaging a seat I 36 at the bottom of the housing I32. The valve is operated. by a stem I38 threaded through the valve casing and having a handle I40 for moving the valve into and out of engaging position with the valve seat I36. EX- tending laterally from the valve casing I32 is a pipe I42 which is connected by means of a fitting I44 into the lower, end of the cylinder 94 so that pressure. may be admitted to the bottom of the cylinder and the valve may be opened to relieve pressure applied through the valve I 06 to the cylinder of the power cutter and to by-pass the pressure and fluid back to the supply cylinder 94. When pressure is. applied to operate the power cutter, the valve I34 is closed and the valves. I02 and I06 are. automatically operated. towithdraw fluid from the cylinder 94 upon anup-stroke. of the plunger I I4 and to apply additional pressure to the power cutter through the valve I06 by the down-stroke of the plunger I I4.

With this construction, the power cutter is easily applied so that the jaws are in clamping engagement and in positiontocut, grip. or clamp an object between the jaws or the-jaw members 24 thereof. To release the jaw members I0 for moving the jaws apart, it may be necessary to open the relief and by-pass valve I32 which relieves any pressure upon the cylinder 52, and plunger so that the jaw members I0: may be pressed together moving the collar 56 relatively inward within the projection 64 of thejaw members. This separates the engaging jaw portions so that a rod, cable or plate to be cut or clamped may be inserted between theclamping jaw portions as desired.

Pressure is then applied between the piston 50 and cylinder 52 by'operating the handle I22-which' causes the collar 56 carried by the cylinder 52 to move outwardly upon the plunger 5250 that the inclined surfaces 58 of the collar engage the adjacent inclined surfaces 66 of the jaw members pressing them angularly apart and partially separating the power applying ends of the jaw mem bers to take up any slack or lost motion between the collar 56 and the collar 68 surrounding the cylinder so that the further application of pressure from the pump tending to separate the plunger'50 and the cylinder 52 will engage the collar 68 and through the arm 18 will apply pres.- sure received by the collar to the extreme ends of the jaw members I0 and held nearly in. a straight line, at opposite sides of the collar 68 so that the greatest leverage will be applied;

If it is desired to hold the power cutter in a fixed position, clamping an article between the jaws thereof, the fluid pressure may be maintained in the cylinder 52, or it may be increased it may be decreased either slowly or suddenly by opening the valve I32.

To release the jaw members, the valve I32 must be open to permit a flow of the fluid under pres.- sure through the by-pass I 42, whereupon the power applying ends of the jaw members may be moved together, the collar 68 engaging the collar 56 and moving it inwardly until the jaws. are released'or separated as desired.

This construction may be made in large per.-

manently mounted sizes, but it is particularly adapted to be produced in small or portable sizes so that not only the jaws. but also the connected power applying pump may be adapted and included as a portable part of the mechanism.

While I have thus described a preferred embodiment which has been described in some detail, it should be regarded by way of illustration and example rather than a restriction or limitation thereof, as many changes in the construction, combination and arrangement of the parts may be made without departing from the spirit and scope of the invention.

1 claim:

1. A power cutter, comprising a pair of jaw members pivoted together adjacent the jaws thereof, a plunger and means for connecting it to the jaw members at the pivot thereof, a cylinder movable upon the plunger having a collar at the inner end with opposite contact surfaces thereon, the jaw members having inner projections adapted to be engaged by the projections of the said collar when the cylinder is moved inwardly to position the collar between the projections on the members and the pivot thereof, means movable on the cylinder engaged by the collar and connected to the outer ends of the members remote from the jaws thereof to actuate the jaws, means for applying pressure to the cylinder for moving the projections of the collar in engagement with the projections of the members to initially separate the jaw members when the cylinder is moved relative to the plunger and to engage the collar movable on the cylinder for applying pressure to the ends of the jaw members and to the jaws.

2. In a power cutter, a pair of jaw members and a pivot connecting them adjacent to the jaws, a cross head connected to the pivot, a plunger connected to the cross head, a cylinder movable on the plunger between the power applying ends of the jaw members, the jaw members having projections at their inner edges adjacent but spaced from the pivot thereof, a collar attached to the cylinder having opposite projections to engage those of the jaw members when the cylinder is moved outwardly, a collar movable upon the cylinder, a lost motion connection between the movable collar and the fixed collar to permit the movable collar to approach the fixed collar, arms connecting the movable collar to the power applying ends of the jaw members, and means for applying fluid pressure to the cylinder to initially separate the jaw members by the engagement of the said projections of the collar with the projections of the members and to take up the lost motion connection between the collars and to apply the collar loose on the cylinder to the further separation of the jaw members.

WILLIAM F. McPI-IEE.

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

UNITED STATES PATENTS Number Name Date 185,975 Sellers Jan. 2, 1877 728,968 Young May 12, 1903 958,972 Pellisier May 24, 1910 1,019,689 Nelson Mar. 5, 1912 2,165,985 Schwentler July 11, 1939 2,228,635 Magennis Jan. 14, 1941 2,349,507 MacGraham May 23, 1944