US2991675A

US2991675A - Crimping tool

Info

Publication number: US2991675A
Application number: US772878A
Authority: US
Inventors: Ustin George
Original assignee: Buchanan Electrical Products Corp
Current assignee: Buchanan Electrical Products Corp
Priority date: 1958-11-10
Filing date: 1958-11-10
Publication date: 1961-07-11
Anticipated expiration: 1978-07-11
Also published as: DE1136391B; FR1240271A; GB886259A

Description

July 11, 1961 G. USTIN 2,991,675

CRIMPING TOOL Filed Nov. 10, 1958 3 Sheets-Sheet 1 (I) o O N (D I a o A; u N g 1" I m m w 28, 23 00 LL 9 4% o q'p g L| In Wm """wu W 'mmWNW- g 8 H9) o o I O3 I m N g :5 I Q a; g (9 LL E 93 INVENTOR I GEORGE USTIN co 4M a"? ATTORNEY July 11, 1961 Filed Nov. 10, 1958 G. USTIN CRIMPING TOOL 5 Sheets-Sheet 2 r N m m m INVENTOR m GEORGE USTIN ATTORNEY United States Patent 2,991,675 ORIMPING TOOL George Ustin, Verona, N.J., assignor to Buchanan Electrical Products Corporation, Hillside, N.J., a corporation of New Jersey Filed Nov. 10, 1958, Ser. No. 772,878 7 Claims. (Cl. 81-15) This invention relates to electricity and more particularly to an improved tool for making a solderless crimped connection of a terminal to conducting means of one or more wires. Such a tool will be hereinafter sometimes referred to more simply as a crimping tool.

It is known to provide a crimping tool comprising a die'holder having a bore therethrough defining an axis, a plurality of crimping dies carried by the die holder and having crimping portions facing the axis, a carrier member rigidly attached to the die holder and an operating member engaging the dies and capable of relative rotation with respect to the die holder and the carrier member in one direction about the axis during a crimping stroke of the tool to cause the crimping portions of the dies to converge toward the axis in the bore. The bore is adapted to receive and contain a ferrule of the terminal with the conducting means of the wire or wires therein, and the crimped connection is effected during the crimping stroke referred to.

In order to assure completion of the crimping stroke, that is, that the crimping portions of the dies will converge to the desired extent, and thus to avoid the possibility of a loose crimped connection, it is desirable that the tool be provided with means for preventing, once the crimping stroke has started, relative rotation of the carrier and operating members in the opposite direction until the desired amount of convergence of the crimping portions of the dies toward the axis has taken place. One successful prior tool of the type described above includes a ratchet between the carrier and operating members, the ratchet preventing relative rotation of these members in the opposite direction until the completion of the crimping stroke. This prior tool also includes a trigger carried by one of the members and a projection carried by the other member and the projection has a free end confronting the trigger and adapted to engage the trigger at the completion of the crimping stroke thereupon to move the trigger to prevent further relative rotation of the members in said one direction and to release the ratchet to permit relative rotation of the members in the opposite direction.

The prior tool has been found, however, to be subject to the disadvantage that it is possible for the operator to trip the trigger with his or her finger either accidentally or by design, before the completion of the desired crimping stroke, thus to release the ratchet and permit premature rotation of the members in the opposite direction. The result is a faulty crimped connection. This has been found to be particularly prevalent where the operator is on a piecework basis.

In a first aspect the present invention provides a cover for the trigger. The cover has an aperture therethrough which is adapted to receive only the free end of the projection to permit actuation of the trigger to release the ratchet.

It is also desirable that the length of the crimping stroke be capable of adjustment, not only to compensate for wear of parts but also to achieve optimum crimped connections where it is desired to use terminals having ferrules of different wall thicknesses and/ or inside diameters, and/or where it is desired to use the tool to crimp terminals to conducting means of different sizes. In the prior tool the projection is an adjustable stud having an external thread threadedly engaging the member which Patented July 11, 1961 carries the projection. The free end of the stud also has external wrenching surfaces to facilitate the turning thereof. In use the stud is turned until the free end is positioned for the desired length of crimping stroke. The prior tool also has a nut having external wrenching surfaces, an internal thread threadedly engaging the stud thread and a surface confronting the member which carries the stud. When the stud is positioned with its free end in the desired location the nut is rotated until the nut surface frictionally engages the member which carries the stud, thus to prevent the stud from thereafter accidentally moving away from the desired position. This arrangement is subject to the disadvantage that it is possible for unauthorized personnel to tamper with the stud adjustment, usually by shortening the crimping stroke, merely by turning the stud and/or the nut by engaging the external wrenching surfaces referred to with a pair of pliers.

In a second aspect the present invention provides a stud having an external thread and a free end which is substantially circular in all sections perpendicular to tthe stud axis and a nut having an internal thread in screw threaded engagement with the stud thread, a circular external configuration and a surface adapted for frictional engagement with the member which carries the stud. Thus the stud adjustment can not be readily tampered with.

It is also desirable that the tool include means for properly locating a terminal with respect to the crimping dies. Accordingly the prior tool includes a terminal locator aligned with the die holder bore. This locator includes a terminal stop which is positioned crosswise of the die holder axis and is spaced a readily adjustable distance from the die holder. As long as the tool is used to crimp terminals of given dimensions it is desirable that the stop remain in the proper fixed location.

The present invention contemplates the use of a separate and distinct terminal locator for each type of terminal, and accordingly in a third aspect this invention provides means for releasably holding an electric terminal locator in alignment with the die holder bore. In the hereinafter disclosed example of the invention this means includes a locator retainer in the form of a slide movable between a retracted and a holding position and a bridge for holding the slide in place, as will be explained in detail.

Each of the three aspects of the invention contributes to the attainment of proper crimped connections, and each can be advantageously used by itself, any two can be advantageously used in combination or all three can be advantageously used in combination.

Accordingly important objects of the invention are to provide an improved crimping tool possessing the advantages set forth above, either singly or in any combination.

The above and other objects and advantages will appear from the following description of an example of the invention and the accompanying drawings thereof in which:

FIG. 1 is an elevational view of a tool in accordance with the invention;

FIG. 2 is a view on line 2-2 of FIG. 1;

FIG. 3 is an elevational view of the slide referred to above;

FIG. 4 is a view on line 44 of FIG. 3;

FIG. 5 is a view on line 5-5 of FIG. 3;

FIG. 6 is an elevational view of the bridge referred to above;

FIG. 7 is a view on line 7-7 of FIG. 6;

FIG. 8 is a view on line 88 of FIG. 2 with part of the structure broken away for clarity;

FIG. 9 is a view similar to FIG. 1 but with certain parts in a different position and with part of the structure broken awayfor clarity;

FIG. is a view similar to FIG. 2 but with part of the structure broken away for clarity;

FIG. 11 is an enlarged view on line 11-11 of FIG. 1;

FIG. 12 is an enlarged fragmentary view of what is shown at the righthaud end of FIG. 9;

FIG. 13 is a plan view of the trigger cover as seen from line 13-13 of FIG. 12; and 1 FIG. 14 is a view on line 1414 of FIG. 12.

The drawings show a crimping tool 16 comprising a die holder 18 (FIGS. 8 and 11) having a bore or crimpin'g location or station 20 therethrough defining an axis and two parallel plane end surfaces 21 perpendicular to the axis, a plurality (four as shown) of crimping dies .22 carried by die holder 18 and having crimping portions 24 facing the axis. Tool 16 also includes a channel-shaped carrier member 26 having two parallel plane side portions 28 embracing end surfaces 21 and rigidly attached to'clie holder 18 as by nuts 30 and screws 32 passing through appropriate aligned holes through die holder 18 and side portions 28. Carrier member 26 also has a web portion 34 joining side portions 28.

Tool 16 further includes an operating member 36 having-a cam surface 38 encircling and confronting die'holder 18 and engaging dies 22.

Carrier member 26 and operating member 36 as shown are in the form of handles which can be squeezed together. Thus operating member 36 is capable of relative rotation with respect'to die holder 18 in one direction (indicated by arrow a in FIG. 1) during a crimping stroke of tool 16 to cause dies 22, including crimping portions 24, to converge toward the die holder axis, with crimping 'portions 24 in bore 20.

Members

26 and 36 have

free ends

40 and 42, respectively, remote from die holder 18.

Thus an electric terminal can be placed with its ferrule or wire receiving portion in bore 20, and by squeezing

members

26 and 36 together the terminal can be crimped to conductors in the ferrule.

As stated, it is important that a full crimpingstroke be performed. To this end tool 16 is provided with ratchet mechanism, indicated generally at 44 between

members

26 and 36, which, once a crimping stroke has begun, prevents relative rotation in the opposite direction, that is, prevents divergence of

members

26 and 36 until the desired crimping stroke has been completed.

A trigger 46 is carried by carrier member 26, being pivotally mounted at 47 between side portions 28 near end 40. Trigger 46 is operatively associated with ratchet mechanism 44 by a lever 48.

Between trigger 46 and web portion 34 is a trigger stop 50 rigidly mounted on carrier member 26.

Trigger 46 is rotatable from the illustrated position thereof into engagement with stop 50 to release ratchet mechanism 44 thereupon to permit relative rotation of

members

26 and 36 in the direction opposite that indicated by arrow a (FIG. 1).

A stud 52 has an external thread threadedly engaging operating member 36 and a free end 54 confronting trigger 46. Free end 54 is substantially circular in all sections perpendicular to the axis of stud 52 and is adapted to engage trigger 46 at the completion of the crimping stroke thereupon to move trigger 46 as aforesaid, releasing ratchet mechanism 44 so that rotation of

members

26 and 36 in the opposite direction can take place. Simulta eously trigger 46 engages stop 50 thus positively ending the crimping stroke.

As aforesaid, it is desirable that it be impossible for trigger 46 to bemoved except by free end 54 of stud 52. To that end this invention provides a cover 56 which can conveniently be, and as shown is, of sheet metal, mounted pivotally at 47 to carrier member 26. Cover 56 base first portion 58 completely overlying trigger 46 between trigger 46 and operating member 36, except thatanselliptical aperture 60 is provided through portion 58 in the path of tion,

. 4 free end 54 of stud 52. Thus free end 54 can pass through aperture 60 to actuate trigger 46. Aperture 60 is as small as possible and the reason for its being elliptical will appear. The major axis of the ellipse runs lengthwise of member 26.

Cover 56 has a second portion 62 between trigger 46 and free end 40 of member 26. As shown portion 62 engages web portion 34, thus preventing cover 56 from itself being moved to actuate trigger 46.

Cover 56 further has a pair of side tabs64 depending from opposite sides of portion 58 and resting on stop 50. Tabs 64 enhance the rigidity of cover 56 and also aid in preventing undesired movement of cover 56.

'Member 36 has a boss 66 including a. plane surface 68 facing member 26. Member 36 also has a tapped hole 70 therethrough intersecting surface 68. The axis of hole 70 is perpendicular to surface 68, and stud 52 is in screw threaded engagement with hole 70.

To set stud 52 in the desired place and thus to achieve the desired length of crimping stroke, a nut 72 is provided. Nut 72 has an internal thread in screw threaded engagement with the thread of stud 52, a cylindrical external configuration and a surface 74 which is adapted for frictional engagement with surface 68. Nut 72 has a pair of aligned radial'holes 76 adapted to receive drill rod or the like, by means of which nut 72 can be rotated either into or out of frictional engagement with surface 68.

Thus when stud 52 has been turned to the desired posinut 72 is turned as aforesaid into tight frictional engagement with surface 68, thus to prevent rotation of stud 52 until it is desired to change the length of the crimping stroke and unauthorized changes in the setting are prevented.

For the various settings of stud 52, it will, at the conclusion of the crimping stroke, engage trigger 46 at different angles; hence the ellipticality of hole 60.

Side portions 28 have aligned circular apertures 78 and 80 therethrough, which are also aligned with bore 20 of die holder 18. Aperture 78 is larger than the adjacent end of bore 20.

Tool 16 also includes means for releasably holding an electric terminal locator 82 having an external circumferential fiange 84 in alignment with bore 20 with flange 84 in aperture 78. Locator 82 as shown is tubular and has a closed end 86 axially spaced from flange 84.-

The last mentioned means includes a locator retainer conveniently of sheet metal and in the form of a slide 88 having projecting means in the form of a pair of spaced tines 90. Slide 88 is movable in two opposite directions perpendicular to the axis of die holder 18 between a retracted position (FIG. 9) and a holding position (FIGS. 1, 2, 10 and 11) in which tines 90 overlap aperture 78 with aperture 78 between tines 90 and die holder 18 and in which tines 90 are adapted to overlap locator flange 84. The locator holding means also includes a set screw 92 for releasably holding slide 88 in its holding position. More specifically, slide 88 has a tapped hole 94 therethrough and with which screw 92 is in threaded engagement. Screw 92 may be prevented from falling out of hole 94 by staking. That side portion 28 of member 26 which contains aperture 78 has an elongated clearance slot 96 (FIG. 11) therethrough and through which the shank of screw 92 passes. Screw 92 is adapted for frictional engagement with die holder 18 to hold slide 88 in its holding position.

The locator holding means further includes a plate 98 rigidly attached to that side portion 28 having aperture 78, as by one pair of nuts 30 and screws 32. Plate 98 has confronting spaced straight surfaces 100 on opposite sides of the axis of die holder 18. Times 90 of slide 88 are located between and are guided by surfaces 100.

A bridge 102 is provided to hold slide '88 in position. Bridge 102 is rigidly'attached to plate 98, as by the other pair of nuts 30 and screws 32, and bridge 102 spans guide surfaces 100. Slide 88 passes between bridge 102 and die holder 18. Bridge 102 has a pair of depending tabs 104 providing surfaces 106 and slide 88 has a pair of surfaces 108 confronting surfaces 106,

surfaces

106 and 108 adapted to engage each other when slide 88 is in its retracted position, thus to limit the movement of slide 88 away from the axis of die holder 18.

Bridge 102 contains an elongated slot 109 therethrough, through which the shank of screw 92 also passes. Screw 92 slides in

slots

96 and 109 as slide 88 moves between its holding position and its retracted position.

Thus with a proper electric terminal locator 82 assembled with tool 16, the terminal portion of an electric terminal of a given size can be inserted through aperture 80 into the opening in the locator 82, the opening having a transverse dimension and shape to receive the terminal portion so that the wire receiving portion of the electric terminal is held in proper transverse alignment in the dieholder bore. The wire receiving portion is considered in proper transverse alignment when it is centered in the bore 20 so that all the dies 24 strike the wire receiving portion of the terminal at the same time. The locator 82 also has a stop surface which limits the insertion of the terminal into the opening so as to properly longitudinally position the wire receiving portion in the bore. In the locator illustrated, the terminal portion of an electrical terminal would be inserted in the opening as far as it will go, that is, untilthe end of the terminal encounters closed end 86 of locator 82. When this has happened the terminal ferrule will be in proper position for crimping. If it is then desired to crimp a different sized terminal it is merely necessary to turn screw 92 out of engagement with die holder 18, move slide 88 from its holding position to its retracted position, replace locator 82 with a different one, move slide 88 back to its holding position and retighten screw 92 against die holder 18.

The locator could assume different forms. ample, it could be open at both ends and have an annular flange acting as a stop surface which is for engagement with the terminal ferrule. In this case the locator could be used with terminals having ferrules of the same dimensions but which are otherwise of different dimensions.

The invention is well adapted to the attainment of the above and other objects and advantages.

Many changes which will occur to those skilled in the art can be made without departing from the invention. Therefore the illustrated and described details are not to be taken as limitations on the invention except as those details may be included in the appendedclaims.

What is claimed is:

1. In a crimping tool comprising a die holder having a boretherethrough defining an axis, a plurality of crimping dies carried by said holder and having crimping portions facing said axis, a carrier member rigidly attached to said holder, and an operating member engaging said dies and capable of relative rotation with respect to said holder and said carrier member in one direction about said axis during a crimping stroke of said tool to cause said crimping portions of said dies to converge toward said axis in said bore: a ratchet between said members for preventing relative rotation in the opposite direction until completion of said crimping stroke; a trigger carried by one of said members and operatively associated with said ratchet; a stud having an external thread threadedly engaging the other of said members and a free end confronting said trigger and substantially circular in all sections perpendicular to the stud axis and adapted to engage said trigger at the completion of said crimping stroke thereupon to move said trigger to prevent further rotation of said operating member in said one direction and to release said ratchet to permit rotation of said operating member in the opposite direction; a cover for said trigger, said cover having an aperture therethrough adapted to receive only said free end of said stud to per- For exinternal adapted mit actuation of said trigger; and a nut having an internal thread in screw threaded engagement with said external thread and also having a cylindrical external configuration and a surface in frictional engagement with said other of said members.

2. In a crimping tool comprising a die holder having a bore therethrough defining an axis and parallel plane end surfaces perpendicular to said axis, a plurality of crimping dies carried by said holder and having crimping portions facing said axis, a channel shaped carrier member having parallel plane side portions embracing'said end surfaces and rigidly attached to said holder and a web portion joining said side portions, and an operating member having a portion encircling said holder and engaging said dies and capable of relative rotation with respect to said holder and said carrier member in one direction about said axis during a crimping stroke of said tool to cause said crimping portions of said dies to converge toward said axis in said bore, said carrier member aving a free end: a ratchet between said members for preventing relative rotation in the opposite direction until completion of said crimping stroke; a trigger carried by said carrier member and located between said side portions and operatively associated with said ratchet; a stud having an external thread threadedly engaging said operating member and a free end confronting said trigger and substantially circular in all sections perpendicular to the stud axis and adapted to engage said trigger at the completion of said crimping stroke thereupon to move said trigger to prevent further rotation of said operating member in said one direction and to release said ratchet to permit rotation of said operating member in the opposite direction; a cover for said trigger attached to said carrier member and having a first portion between said trigger and said operating member and a second portion between said trigger and said free end of said carrier member, said first portion having an aperture therethrough adapted to receive only said free end of said stud to permit actuation of said trigger; and a nut having an internal thread in screw threaded engagement with said external thread and also having a cylindrical external configuration, and a surface in frictional engagement with said operating member, and said nut having a pair of circumferentially spaced holes extending from said external configuration toward said internal thread.

3. In a tool for crimping electric terminals onto conductors, said tool comprising a die holder having a bore therethrough defining an axis and parallel plane end surfaces perpendicular to said axis, a plurality of crimping dies carried by said holder and having crimping portions facing said axis, a channel shaped carrier member having side portions having parallel plane confronting surfaces adjacent and embracing and rigidly attached to said end surfaces and a web portion joining said side portions, said side portions having first and second apertures therethrough aligned with said bore, said first aperture larger than said bore, and an operating member having a portion engaging said dies and capable of relative rotation with respect to said holder and said carrier member in one direction about said axis during a crimping stroke of said tool to cause said crimping portions of said dies to converge toward said axis in said bore: a ratchet between said members for preventing relative rotation in the opposite direction until completion of said crimping stroke; a trigger carried by one of said members and operatively associated with said ratchet; a projection carried by the other of said members and having a free end confronting said trigger and adapted to engage said trigger at the completion of said crimping stroke thereupon to move said trigger to prevent further rotation of said operating member in said one direction and to release said ratchet to permit rotation of said operating member in the opposite direction; a cover for said trigger, said cover having an aperture therethrough adapted to receive only said free end of said projection to permit actuation of said trigger; and means for releasably holding an electric terminal --iocator having an external flange in alignment with said bore with said to said end surfaces and a web portion joining said side portions, said side portions having first and second aperturestherethrough aligned with said bore, said first aperture larger than said bore, and an operating member having aportion engaging said'dies and capable of relative rotation with respect to said holder and said carrier memberin one direction about said axis during a crimping stroke of said tool to cause said crimping portions of said dies to converge toward said axis in said bore:

a ratchet between said members for preventing relative rotation in the opposite direction until completion of said crimping stroke; a trigger carried by one of said members and operatively associated With'sai d ratchet; an adjustable studhaving an external thread threadedly engaging the other -'of said members and a free end confronting said trigger and substantially circular in all sections perpendicular to the stud axis and adapted to engage said trigger at the completion of said crimping stroke thereupon to move said trigger to prevent further rotation of said operating member in said one direction and to release said ratchet to permit rotation of said operating member in the opposite direction; a nut having an internal thread in screw threaded engagement with said external thread and also having a circular external configuration and a surface in frictional engagement with said other ofsaid members; a cover for said'triggensaid cover having an aperture therethrough adapted to receive only said free end of said stud to permit actuation -of said trigger; and means for releasably holding an electric terminal locator having an external flange 'in alignment with said bore with said flange in said first aperture.

5. In a crimping tool comprising crimping means and first and second members capable of relative rotation in one direction during a crimping stroke of said 'tool to cause said crimping means to perform a crimping action: a ratchet between said members for preventing relative rotation in the opposite direction until completion of said crimping stroke; a trigger carried by one of said members and operatively associated with said ratchet; a projection carried by the other of said members and having a free end confronting said trigger and adapted to engage said trigger at the completion of said crimping stroke thereupon to move said trigger to prevent further rotation of said members in said one direction and to release said ratchet to permit relative rotation of said members in the opposite direction; and a cover for said trigger, said cover having an aperture therethrough adapted to receive only said free end of said projection to permit actuation of said trigger.

6. In a tool for crimping wire receiving portions of electric terminals of a first ftype onto conductors at a crimping station, said terminals also having terminal portions; a first electric *termi-na'l locator in predetermined position with respect "to said crimping station and having an opening therein in open communication with said crimping station and a stop surface, said opening being of a transverse dimension and shape to receive said terminal portion so that said wire receiving portion is held in proper transverse alignment in said crimping station, said stop surface limiting the insertion of said terminal into said opening so as to properly longitudinally position said wire-receiving portion'in-said crimping station and rapidly releasable means holding said first electric terminal locator in said predetermined position, said -rneans including a locator retainer having a pro- -jection andmovable between a retracted position so that said first locator can be replaced by another locator to adapt isaid tool for crimping electrical terminals of a second type and a holding position in which said projection overlaps said crimping station and in which said projection is adapted to overlap a portion of said first locator to hold said locator in alignment with said crimping station as aforesaid, said holding means also including means for releasably holding said retainer in said holding-position, and means separate from said-retainer holding said retainer in assembled relationship with the remainder of said tool.

7. A tool for crimping a wire receiving portion of an electric terminal of a first type onto a wire, said terminal also having a terminal portion, said tool comprising means providing said tool with a crimping location, die-means convergeable on said crimping location during a crimping stroke of said tool, an electric terminal 10- cator in predetermined position with respect to said crimpinglocation and having an opening therein in'open communication with said crimping location and a stop surface, said opening being of a transverse dimension and shape to receive said terminal portion so that said wire receiving portion is held in proper transverse alignment in said crimping location, said stop surface limiting the insertion of said terminal into said opening so as to properly longitudinally position said wire receiving portion in said crimping location, and rapidly releasable means holding said locator in said predetermined position, so that said locator can be replaced by another 10- cator to adapt said tool for crimping an electric terminal of a second type.

References'Cited in the file of this patent UNITED STATES PATENTS 478,121 Miller July 5, 1892 691,477 Murphy Jan. 21, 1902 1,064,182 Thompson June 10, 1913 1,528,691 Price Mar. 3, 1925 2,467,012 Deuschle Apr. 12, 1949 2,696,747 Berg'an- Dec. 14, 1954 2,737,071 Dibner Mar. 6, 1956 2,753,742 Buchanan July 10, 1956 2,933,000 Wood Apr. 19, 1960 FOREIGN PATENTS 367,221 Great Britain Feb. 18, 1932