US2887916A - Crimping tools - Google Patents

Description

May 26, 1959v T. c, FREEDOM CRIMPING TooLs 2 Sheets-Sheet 1 Original -F'iled Nov. 25. 1953 FIG.|

IIA

xNvENToR. THOMAS C. FREEDOM ATTORNEYS.

CRIMPING TOOLS 2 Sheets--SheeI 2 Original Filed Nov. 25, 1953 F'IG.2

lNvEln-.ORV THOMAS C. FREEDOM BY. 6%, A mgm.

ATTORN EYS.

United States Patent() CRllVIPING TOOLS Thomas C. Freedom, Mechanicsburg, I Pa., assigner to AMP Incorporated, a corporation of New Jersey Continuation of application Serial No. 394,448, Novem- The present invention relates to crimping tools, more particularly of the type employed in securing terminals to electrical conductors by pressing portions of the terminals on or around portions ofthe conductor. This application constitutes a continuation of my previously filed application, Serial No. 394,448, filed November 25, 1953, now abandoned, which abandoned application was a division of application 769,381, now Patent No. 2,693,218.

Known devices for this purpose include portable hand tools provided with crimping dies which are moved by hand pressure against portions of the terminals to force the latter into firm engagement with portions of the conductors. There are also power operated crimping machines for large scale production of terminal equipped conductors,

An object of the present invention is to provide a crimping tool which will combine some of the advantages of a portable hand tool with accurately predetermined crimping pressure, and in general a precision which will assure uniformly excellent work.

A further object of the invention has been to provide a portable crimping tool whereby the parts to be secured together by crimping are-initially held in crimping position by a preliminary and relatively gentle gripping or clamping action and then subjected to the final crimping pressure. An advantage in this feature is that it insures more accurately formed products, safer operation, and more rapid production.

Another object is so to construct a crimping' tool that the heavy duty parts are reduced to a few small parts and most of the parts can be made relatively light weight and inexpensive.

1Other objects and contemplated advantages and benecial results in manufacture and use of said4 invention will more fully appear from the following specification and the appended drawings wherein a preferred embodiment and modifications thereof are described and illustrated. It is to be understood that these are not intended to be exhaustive or limiting but are intended for purposes of illustration in order that others skilled in the art may fully understand the invention, the principles thereof and the manner of applying it in practical use and so that they may modify and adapt it in Various forms, each as may be best suited to the conditions of a particular use.

In said drawings, wherein like reference characters are employed to identify similar parts:

Figure l is a side elevation, with outer wall portions broken away and with interior portions shown partly in longitudinal vertical section, of an embodiment of the invention which provides relatively gentle gripping of the terminal and conductor by a preliminary manual operation and crimping of the terminal on the conductor by a final and more powerful application of pressure, the parts being shown in their relative positions during said final and more powerful application of pressure;

Figure 2 is a fragmentary view illustrating parts shown in Figure l but-in their relative positions when the tool is notin Ause;

Figure 3 is a fragmentary view illustrating said parts in their relative positions when gently gripping the terminal and conductor preliminary to application of crimping pressure;

Figure 4 is a fragmentary view showing a modification; and

Figure 5 is a view in perspective of one form of terminal or connector applied to a conductor by crimping.

Referring now to Figure 1, the appliance there shown comprises a housing having a hand grip portion 10, a rigid die-holding jaw 11, and a piston-carrying portion 12. Dies 13 and 14 are mounted to cooperate, first in gripping a terminal 15 while positioned on a conductor 16 (Figure 3) and then in applying pressure to said terminal 15 to secure the same thereon in crimped condition, Figure 5. One of said dies, as 13, is removably fitted to said rigid jaw 11 and the other die 14 to a rocking -jaw 17, and secured thereon, e.g., by screws 18. Dies 13 and 14 are interchangeable with other dies having crimping portions designed for use in applying terminals to conductors differing in gauge or other characteristics.

The rocking jaw 17, pivoted at 19, is actuated by a toggle having a connecting link 20 and a rocking link 21. One end of rocking link 21 is pivoted at 22 on the handle 10 which is rigidly connected to jaw l1; and one end of connecting link 20 is pivoted at 23 to an inner end portion of rocking jaw 17. The other end of connecting link 20 is pivoted at 24 to an intermediate portion of rocking link 21; and an integral extension of the free end of said 1ink2221 forms in effect a toggle operating lever pivoted at A spring 25 mounted with one endfxed in the casing at 26 has its free end bearing against the pivot pin 24. Said spring tends normally to hold the toggle links 20 and 21 in the relative positions shown in Figure 2 and thereby to maintain jaw 17 in open or terminal receiving position. A grip lever 27, also pivoted at 22, is provided wtih a flanged arm or end piece 28 in position to engage an edge portion of toggle link 21 between the pivots 22 and 24, as shown in Figures 2 and 3. An edge portion of the lower or operating end of the grip lever 27 normally extends outwardly from grip portion 10 through a longitudinal slot 29.

In operation, beginning with the parts positioned as seen in Figure 2, the operator with one h-and places a portion of a terminal blank wit-h a conductor extending therethrough on the recessed face 30 of' die 13. Holding the tool by its grip portion 10 in his other hand, and with some of the fingers of that hand bearing on end portions of lever 27 which protrude from slot 29, operator squeezes or deflects said end of lever 27 inwardly.` This causes toggle link 21 to swing counter clockwise on pivot 22 (Figure 3) against resistance of spring 25, thus bringing the die 14 down into gently but firmly gripping engagement with terminal 1 At this stage the fluid-pressure motor is operated to apply toggle actuating pressure on rocking link 21 through rlcaller 31 pivoted at 32 at the upper or free end of said In the illustrated embodiment, pneumatic or fluid pressure means for this purpose include a hollow cylinder 33 (Figure l) open at its inner end and closed at its outer end and a piston assembly therein comprising a plate 34, and piston 35 with a cup gasket 36 clamped between them by means o'f a nut 37 and bolt 38 on a push block 39. A spring 40 is positioned between said piston and a flanged ring or keeper 41 which is retained in operative position by a split ring 42 resting in an interior annular groove 43 in the wall of cylinder 33. Spring 40 tends to press the piston 35 and the push block 39 toward the retracted position, dotted lines, Figure l, full lines, Figures Zand 3.

As seen 1n Figure 3, rocking link 21 has been swung by manual operation from its normal inoperative position, Figure 2, to bring roller 31 into the path of movement of push block 39 and in position to be engaged and actuated, thereby to effect crimping movement of the jaw 17 and die 14 toward rigid jaw 11 and die 13.

For this purpose, fluid pressure is released into cylinder 33 by suitable valve means, actuated from a trigger 44 having a stem 45 extending inwardly through an opening in trigger lever 27. A spring 45 presses trigger 44 outwardly. The inner end of stem 45 is positioned to engage a lever 47 pivoted at 46. A free end portion of said lever 47 engages an exposed or outer end portion of a plunger pin 49 which is held yieldingly against said lever by spring 50.

Said plunger pin 49 is mounted to slide endwise in an end portion of a passage or conduit 64 in housing 51, the other end of which opens into a valve chamber 52. A ball valve 53 in said chamber pressed against its seat by spring S4 controls the opening between passage 64 and chamber 52. This ball valve 53 may be unseated by inward endwise movement of plunger pin 49. An inner end portion of said plunger pin is of less diameter than the conduit 64 to permit passage of uid thereby to the ports 57 or 58 whereas an outer portion is of a size to till conduit 64 so as to effectively close the exhaust port 58 when the pressure port 57 is open.

Fluid under pressure is admitted to chamber 52 from a supply pipe 55 through a passage 56. The passage 64 is provided at one end portion with a pressure port 57 and a relief port S8 spaced therefrom. A pipe 59 connects pressure port S7 with the interior of cylinder 33.

To actuate push block 39 by uid pressure while the parts are in the positions shown in Figure 3, operator presses trigger 44. This produces endwise inward movement of plunger pin 49 in the course of which an intermediate portion of said plunger closes exhaust port 58 and an end portion opens valve 53 to pass fluid from chamber 52 into passage 64, and thence through port 57 and pipe 59 into cylinder 33.

When pressure on trigger 44 is released, spring 50 returns plunger pin 49 to outwardly extended position, thus opening relief port 58 into communication with cylinder 33 through conduit 64, port 57 and pipe 59. Spring 54 aided by the Huid pressure admitted into chamber 52 causes ball valve 53 to seat.

As shown in Figure l the exhaust port 58 is just beginning to open. If the trigger 44 is left released, spring 50, aided by back pressure in passage 64 from cylinder 33, will, of course, push the slide 49 back so as to fully open port 58. As pressure is thus relieved from cylinder 33, the piston assembly and push block 39 are returned to retracted position by spring 40, and the remaining movable parts resume their original vpositions shown in Figure. 2.

In the modification shown in Figure 4, the split lever 6i) pivoted at 22 `corresponds in function to grip lever 27 of Figures l, 2, and 3. The lever 60 includes a spring hinge portion 61 which is stiffer or stronger than spring 25. Thus, when lever 60 is swung about pivot 22 from normal inoperative position, by pressure of the operators fingers, spring 25 yields and the connected parts produce in effect the initial clamping or gripping of the terminals and connectors previously described in connection with manual operation of lever 27.

To produce the iinal power actuated crimping movement of jaw 17, a stronger squeeze on lever 60 bends it at 61 to the position as shown in Figure 4, thus advancing the adjustable threaded triggering pin 62 endwise through opening 63 in lever 60, to bring its free end against lever 47 which, in turn, moves plunger 49 to open Valve port 57.

It will be apparent from the foregoing description and the stated mode of operation of the illustrated embodiments that the present invention supplies a highly eicient portable crimping tool which combines the most advantageous features ofhand and power operation. Other advantages in manufacture and use will be readily recognized by those skilled in the art.

I claim:

l. A crimping tool wherein opposed pivotally connected die carrying jaws are operated manually to hold a work piece between them in position to be die crimped and are power actuated to apply crimping pressure thereto, said tool comprising in combination a jaw supporting frame, a jaw operating toggle having a rocking-link and a connecting link spring-biased toward jaw opening position, said rocking-link being pivoted at one end to said frame, and said connecting link being pivoted at one end to one of said jaws and at its opposite end to an intermediate portion of said rocking-link, a manually operable lever pivoted on said frame said lever comprising a rocking-link engaging arm and an, operating arm manually deflectable to actuate said rocking-link through the rocking-link engaging arm and thereby eiect work piece gripping operation of said jaws, fluid motor actuated toggle operating means including a pusher member movable against spring resistance into operative engagement with a portion of said toggle to effect work crimping operation of said jaws, a motor control valve normally biased in closed condition, and manually operated means for opening said valve includingV a spring biased triggering member mounted on the operating arm of said lever.

2. A crimping tool according to claim 1 and wherein the rocking-link includes a free end portion normally spring held in position at one side of the path of toggle actuating movement of said pusher member and movable into said path with work piece gripping operation of said jaws.

3. In a portable tool for applying electrical connectors and pressure forging them onto wires and the like, the combination of a frame having a handle portion defining a hand grip position, a first forging jaw rigidly secured to said frame, a second forging jaw movably mounted in the frame for relative movement toward and away from said rst jaw, a movable linkage coupled to said movable jaw and having a roller on the free end thereof, spring means urging said movable jaw and said linkage in a tirst direction into a first inoperative position, low power means connected to an intermediate portion of said linkage for actuating said linkage against the force of said spring means for moving said second jaw from said inoperative position into va second gripping position to engage and hold a connector between said jaws, said roller also being moved by said low power means into said second position spaced from its inoperative position, a high power mechanism mounted on said frame including a movable push block, guide means guiding said push block along a path of action directed generally toward said jaws and toward said linkage, ,said push block having a cam surface thereon, one portion of said cam surface being a working surface and anotherportion of said cam surface being adjacent thereto, said working cam surface being aligned by said guide means with said roller and engaging said roller in its gripping position and driving said movable jaw from its gripping position toward said fixed jaw to forge the connector together with a wire, said other portion of said cam surface being aligned with said roller in its inoperative position, said other portion of said cam surface having an inclination with respect to said guide means adaptedto'urge said roller and movable jaw in the same direction as said spring means, for preventing movement of said movable jaw away from said inoperative position, and manual means for controlling application of said low power means and said high power mechanism, respectively,'operable from said hand grip position.

4. In a portable crimping tool for applying electrical connectors andy pressure forging them onto conductors, a portable frame, a tirst forging jaw xedly mounted on said frame, a second forging jaw movably mounted on said frame for relative movement toward and away from sid'iixedjaw and being movable away from said xed jaw into a fully open position for receiving a connector between said jaws, said movable jaw being movable from said fully open position toward said fixed jaw into a partially closed position for gripping and holding a connector, a uid pressure cylinder, a piston reciprocable therein, valve controlled means connected to supply uid under pressure to the cylinder to drive said piston, safety apparatus -to prevent inadvertent operation of said jaws by said piston including a trigger and movable pin assembly for actuating said valve controlled means, a cam block moved by said piston and having a working surface, a movable linkage coupled to said movable jaw, a roller on the free end of said movable linkage, said working surface engaging said roller to move said movable jaw toward said xed jaw, manually controlled means engaging said linkage for moving said movable jaw from said fully open position to said partially closed position, said trigger and movable pin assembly being held by said manually controlled means in an inoperative condition With respect to said valve controlled means when said movable jaw is in its fully open position and being placed in operative condition by said manually controlled means in response to operation of said manually controlled means for moving said movable jaw into partially closed position.

5. A tool for crimping electrical connectors wherein `stationary jaw and a relatively movable jaw, each containA ing a crimping die, means for actuating said movable jaw to grip a connector between the dies, a reciprocable-piston, Huid-pressure actuating means fory moving said jaws to actuate said dies into nal crimping relationship, means for actuating the fluid pressure means and means for translating motion from the reciprocating piston to the jaws, said motion translating means comprising a pusher member secured to the reciprocable piston, said pusher member having a working surface thereon, and a freely rotatable roller connected with the movable jaw, means for moving said roller into andout of the path of the pusher member and simultaneously moving the jaws into a partially closed portion whereby they will grip a connector inserted therein said roller normally held by springbias in a position with the axis of the roller disposed from the path of the working surface of said pusher member to prevent inadvertent actuation of the jaws, and said roller movable into said path concomitant with the connector gripping operation of said movable jaw whereby a crimping force is applied to the jaws only after the roller is moved into the path of the pusher member.

References Cited in the iile of this patent UNITED STATES PATENTS

Images