US3200675A - Crimping device for strapping material operating both during instroke and outstroke of the handles - Google Patents

Description

G. N. WILLIS 3,200,675

ERATING BOTH DURING CRIMPING DEVICE FOR STRAPPING MATERIAL OP INSTROKE AND OUTSTROKE OF THE HANDLES 2 Sheets-Sheet 1 Filed June 3, 1963 INVENTOR.

GRANT NOBLE WILLIS ATTORNEY Aug. 17, 1965 G. N..WILLIS 3,200,675

CRIMPING DEVICE FOR STRAPPING MATERIAL OPERATING BOTH DURING INS'IROKE AND OUTSTROKE OF THE HANDLES Filed June 3, 1963 2 Sheets-Sheet 2 INVENTOR.

GRANT NOBLE WILLIS ATTORNEY United States Patent 3,266,675 CRlMPlN-G DEVHZE FOR STRAPPING MATERIAL QPERATING RUTH DURING TNSTROKE AND UUTSTRGKE 02F THE HANDLES Grant Noble Willis, Bristol, Conn, assignor to The American Manufacturing Company, line, Brooklyn, N.Y., a corporation of Delaware Filed June 3, 1963, 'Ser. No. 234,901 8 Claims. '(Ci. 3l9.1)

This invention relates to crimping tools and in particular to a novel crimping tool for use with non-metallic strapping material.

While metallic strapping has been used for banding packages of all kinds for a number of years, only recently has interest been shown in non-metallic strapping. One type of proposed strapping is made essentially of polypropylene which has been melt-extruded, cooled and stretched to achieve molecular orientation and fibrousness. This type of strapping has a very high tensile strength and resists dimensional change when placed around an object. Reference may be made to the copending continuation application of Robert L. Stanton, Serial No. 241,164 filed November 26, 1962 and entitled Banding Strip and Method of Manufacture Thereof. Strapping made in this manner is very strong in the longitudinal direction. Due to its molecular orientation it is somewhat less strong in a direction transverse thereto. Ordinary sealing clips and tools used to fasten the ends of metallic strapping do not work well wtih this type of non-metallic strapping. One reason for this is that seals for ordinary metallic strapping are customarily sealed by cutting upward or downward transverse flaps in the edges of the seal and in the edges of the overlapped strapping enclosed therein. These flaps prevent the longitudinal slippage of the strapping out of the seal. If such transverse flaps are cut into polypropylene strapping which has been highly-oriented, however, the polypropylene is caused to shred in a longitudinal direction thereby reducing the effective width of the strapping at its most critical area, i.e., in the seal area, since only the uncut part would resist pull in the longitudinal direction.

All known crimping tools used in the strapping industry are so made that the jaws are open when the handles are separated from one another. This requires both hands to be available for holding the device in position to place the jaws of the crimping tool around the seal on the strapping.

In addition, with presently known crimping tools, the seal must first be placed around the strapping itself before the tool is applied to the strapping.

There are no known crimping tools which can with one hand be applied to the seal on the strapping.

There also is known crimping device marketed which automatically reopens the jaws at the end of the crimping operation so as to ready them for the next operation.

Since, for reasons previously stated, it is not desirable to cut transverse flaps in plastic strapping of the type described, the seal should be deformed in a way that avoids cutting the strapping yet holds securely under high tension. One way that has been found successful is to produce a number of transverse corrugations both in the seal and the overlapping strapping contained therein. This requires a substantial amount of force and it is highly desirable to have a crimping tool which can be used by any operator to produce the requisite number of corrugations having the proper depths.

Known crimping tools also generally employ a onestroke operation; that is the complete crimping action is accomplished with one inward movement of the handles. It would be very useful to have a crimping device in which the sealing operation is divided into two parts, i.e.,

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(1) the folding over of the legs of the seals and (2) the production of corrugations in the folded seal.

Present crimping tools have an action such that the operator can remove the tool from the strap even if the sealing action has not been completed so that there is a possibility that the incomplete seal may be weaker than specified or be otherwise imperfect.

It is therefore among the objects of the present invention to provide:

1) A novel crimping device for strapping material, especially non-metallic strapping material.

(2) A novel crimping device for use with highly-oriented plastic strapping such as is made of polypropylene.

(3) A novel crimping device whose jaws are open when the handles thereof are in their innermost position.

(4) A novel crimping device with provision for inserting the seal into the jaws before applying it to the tensioned strapping material.

(5) A novel crimping device which can, by using one hand, he used to position the seal around the strapping material.

(6) A novel crimping device which is constructed to automatically reopen the jaws at the end of the crimping operation. a

(7) A novel crimping device for use with plastic strapping that can produce desired transverse corrugations in the seal and its contents without cutting the surface of the strapping material itself.

(8) A novel crimping device in which the sealing operation is effectively divided into two parts and the force required to effect each step is distributed between the outstroke and the in-stroke of the handles.

(9) A novel crimping device which is so designed that it cannot be removed from the seal once it is applied thereto unless the entire sealing action has been completed in the specified way.

Other objects of the invention will be apparent to those skilled in the art upon perusing the drawings, specification and claims herein.

In accordance with my invention I provide a sealcrimping device having two handles and a number of sets of jaws. The device is so constructed that when the handles are close to one another, the jaws are open and an open seal may be lodged between them before the device is applied to the strapping to be sealed. Alternatively, the seal may, of course, be put on the ends of the strapping that has been tensioned about a package. In either case, when the jaws are around the seal and the seal has been put on the tensioned strapping, the operator moves the handles away from one another. By a lever coupling of the jaws to the handles, the jaws will pivot inward and downward toward one another on the outstroke of the handles. This causes the legs of the seal to be folded toward one another and downward. When the handles are then pressed inward toward one another, the beginning of that movement causes two projecting fingers attached to the handles to engage a spring-loaded member that is coupled by intermediate linkage to the sets of jaws. Further inward movement of the handles pushes the spring-loaded member up which, by means of the intermediate linkage, causes the jaws to pivot downward thereby forcing parts of the folded-over seal (and the strapping enclosed therein) downward into the spaces between a plurality of anvil members. Finally, toward the end of the in-stroke the fingers become disengaged from the spring-loaded member whereupon the latter is pulled down suddenly by the spring and the jaws fiy open to their normal starting position. Then at the end of the sealing operation the handles are together and the jaws are open so that the operator can release the tool with one hand from the sealed strapping.

FIGURE 1 is a front elevation view, partly in section,

o #23 of the crimping device shown with its handles in their innermost positions.

FIGURE 2 is a front elevation view of part of the apparatus shown in FIG. 1 with the front mounting plate removed and showing the jaws in a partly-closed position toward the end of the outstroke of the handles just before projecting fingers attached to the handles snap intoengagement with the spring-loaded member.

FIGURE 3 is an enlarged fragmentary elevation view, partly sectional, of the apparatus shown in FIG. 2 just after the projecting fingers have engaged the spring-loaded member.

FIGURE 4 is a view similar to FIG. 3 showing how the jaws are pivoted downward as the spring-loaded member is forced up as the handles are moved inward.

FIGURE 5 is a detail of FIG. 4 showing how the fingers, toward the endof the inward movement of the handles, are so positioned as to permit the springdoaded member to. be released therefrom and be pulled downward by the spring.

FIGURE 6 is a sectional view of part of the apparatus shown'in FIG. 1 taken along the section line 6-6 in the direction indicated by the arrows.

FIGURE 7 is a sectional view of part of the apparatus illustrated in FIG. 1 taken along the section line 7-7 in the direction of the arrows.

FIGURE 8 is a side elevation view of a seal with overlapping portions of the strapping contained therein which has been corrugated by the novel'apparatus shown in FIG. 1. p

Out-stroke operation and structure Referring now principally to FIGURE 1 andalso to FIGS. 2-7, there is shown my novel crimping tool indicated generally at the numeral 10. The device 10 ineludes two handles 11 and 12 terminated by knobs 11a and 11b. The handles have generally channeled construction for the straight parts of their respective lengths as indicated at the numerals 11c and 11d. They also have curved channeled portions 11c and 11f whose'upper ends are provided with apertures through which pivot pins and 22 are passed. These pivot pins are also respectively passed through aligned apertures in first and second sets of opposed jaws 35 and 37 respectively. The lower ends of the jaws of each set are also provided with apertures through which pivot pins 41 and 4-3 pass, coupling the jaws to two pairs of intermediate linkage members 45, 47 (FIG. 1) and 44, 43 (FIG. 3) located on opposite sides of the tool. It will be noted that in the positions shown in FIGS. 1-3 the outer curved edges of the portions 11c and 11 bear against theinner curved surface of the pins 41 and 43. The reason for this construction will be explained below.

The sets of jaws 35 and 37 are also provided with aligned apertures toward their upper end through which spacer pins 27 and 29 are passed. The ends of these pins have axial threaded apertures at their ends into which screws 24 are screwed. The pins 27 and 29 are also passed through a plurality of stationary anvil members 39 which are interspersed between the jaws 35 and 37 as shown in FIG. 6. The ends of the pins 27 and 29 are fixed, lodged in apertures Within two identical fish-shaped mounting plates 23 and 25 (FIG. 3) whose upper portions are located on opposite sides of the tool. These plates have lower tail sections 23a and 25a which are joined by a pin 31 whose ends are spun over. These tail sections are located in the channels of the handle portions 110 and 11d respectively.

In order to operate the device, the operator grasps the tool It) in the position shown in FIG. 1 with one or both hands and inserts an open U-sectioned seal 60 so that its back rests on the tapered upper edges 39a of the anvils 39 between the open jaws and 37. The seal 60 will be retained in the tool 10 because of two resilient wire members 26 and 28, located on opposite sides of the tool, whose ends are curled around ring bushings 34 (FIG. 7) placed around the pins 27 and 29. These springs exert sufiicient inward pressure upon the. outer surfaces of the upstanding legs of the seal 6% to keep it in position with its backresting on the anvil edges 39a. In order to keep the central straight portions of the springs 26 and 28 from bending inward flaps 25c and 230 are respectively formed in plates 25 and 23.

There are two sets of substantially identical and opposing jaws 35 and 37, each set including four members having tapered lower active edges 37a. The jaws are separated from one another by anvils 3h (see FIG. 6) having upper tapered edges 3%. The spacer pins 27 and 29 pass through apertures in the set 35 aligned with apertures in the left end of the anvils 39 whereas the pin 29 passes through apertures in the set 37 aligned with apertures in the right hand portion of the anvils 39.

The operator can with one hand place the tool 10 containing the seal about the overlapped portions of the strapping material which has previously been tensioned around the package. The operator then grasps the handles 11 and 12 near the knobs 11a and 11b and starts to pull them apart. In so doing, it will be seen that the portions lIe and 11 which have their outer curved edges bear on pins 41 and 43 urge the latter outward thereby causing the . jaws 35 and 37, to pivot about pins 27 and 29 toward one another. This produces a relatively small force of about 200 lbs. at the tips of the jaws. This is a straight lever action with a mechanical advantage of about 25:1. In so doing the lower'tapered edges. 35a and 37a force the legs of the seal inward and downward toward one another. At the same time, the projecting fingers 13 and 14 have started to move downward and outward until, at the point in the outward stroke shown in FIG. 2, their edges 13a and 14a press against the ledge portions Stlc and 50d of the spring-loaded member 50.

Within the handles 11 and 12 are also located respective projecting fingers 13 and 14 that pivot about pivot pins 15 and 16 whose ends are disposed within aligned apertures in opposite portions of the channeled handle members and 11d. In order to bias the fingers 13 and 14 to pivot toward one another, bow-shaped resllient'members'19 and 21 are provided, their lower ends being fixed within the members 13 and 14 respectively whereas their'upper ends bear against pivot pins 41 and 43. The " fingers 13 and 14 are also channeled in construction (see FIG. 6). When the handles are separated still more, the edges 13a and 14a slip down past the ledge Stlc and 50d and then snap into the recessed portions She and 50 respectively. It will be noticed that at this time, the jaws 35 and 37 have their lower tapered edges 35a and 37:: almost parallel to the base of the seal.

p A further slight outward movement of the handles 13 and 14 folds over the legs of the seal completely.

Instroke operation and structure Between the links 45 and 47 and theircounterparts 44 and 43 is located spring-loaded member 50. This member has a pin 50m passing through it which includes terminal portions 500 and 50h. These projections 50a and Silk ride up anddown within slot 23b in the opposed plate 25. As shown in FIG. 6, the pin Stlm also passes through aligned apertures in the lower ends of the members 44 and 48 on one side and through aligned apertures in the lower ends of members 45 and 47 on the other.

The member 50 has. an aperture 50b toward its lower end through'which the top end of a spring 52 is passed, the other end of this spring being fastened around the pin 31 which keeps the ends 23a and 25a of the plates 23 and 25 together. It will thus be seen that normally the member 50 is pulled downward by the action of spring 52. As the member 50 moves down, of course, the pairs of links 45, 47 and 44, 4 8 are pulled down and so the jaws 35 and 37 are pivoted to their open positions.

So long as the handles are notopened more than about of their full outstrokethe pointed free ends and 1472 will be above the top portion of the member 50. However, as stated before when the handles are extended almost to their outermost position the inclined surfaces 130 and14a slide downward against the sides 50c and 50d of the member 50, until the ends 1% and 15b are urged by springs 19 and 21 into the recesses 50:: and 50 Once the outstroke is completed and the legs of the seal 60 have been folded over the strapping parallel to the back of the seal, the operator starts to move the handles toward" one another. As he does so, it will be observed that the tips 13b and 14b of the fingers 13 and 14 start to push the spring-loaded member 50 upwards against the bias of the spring 52. As the handles are brought together the tips 1% and 14b push the member 50 up and thereby cause the pairs 45, 47 and 44, 48 of intermediate linkage members to move up thereby forcing their upper ends to move outwardly. When the fingers 13 and 14 start to operate, the aperture linkage system changes from a straight lever system to a pair of four-bar linkages. The latter linkages are so designed that as the handles come together the mechanical advantage between the ends of the handles and the jaws increases rapidly. As the latter ends move outwardly, it is seen that the jaws 35 and 37 whose lower edges 35a and 37a rest on the folded-over legs of the seal 60 will be forced to pivot downwardly even more so that their lower edges 35a and 37a will force the portions of the seal and its contents directly below them down into the spaces between adjacent ones of the anvils 39 thereby producing corrugations as shown in the View of the processed seal in FIG. 7. This apparatus is capable of producing a total of about 8000 lbs. downward pressure against the anvils 39 with a maximum handle force of 35 lbs. The position of the jaws 35 and 37 at this time is shown in FIG. 4.

After this has been accomplished, further inward movement of the handles will cause the edges 13a and 14a to move upward until they are disposed as shown in FIG. 5 wherein the tips 131) and 14b are clear of the recesses 50:: and 50 At this juncture the strong tension exerted by the spring 52 Will pull the member 50 down between the fingers 13 and 14 with a strong, sudden movement. This downward movement restores the member 50 to its starting position and also pulls down the ends of the linkage pairs 45, 47 and 44, 48. These pairs pull the lower ends of the jaws 35 and 37 downward and inward so that the upper ends pivot outwardly until the original open position of the upper ends of the jaws is restored.

FIGURE 8 is an elevation view of the seal 60 which has had its leg portions folded over and then has been corrugated by the tool 10. The initially free end 64 of the strap is shown as well as the end 62 which is cut by the strap-tensioning apparatus employed. In the view shown, the folded-over leg portions are on the top side of the seal. There are three corrugations 60a having a peak-to-peak height of .135 inch produced in the seal and in its contents. This clip may be made of mild cold-rolled steel having a Rockwell hardness of about B75 and having a thickness of .031 inch. A #1 or #2 finish with an electrolytic zinc coating may be used. The metal of the seal is oriented so that its grain runs transversely to its longitudinal axis. The width of the seal measured from the interior surface of one leg portion to the other (in its uncrimped state) may be of the order of .550 inch to accommodate strapping about .520 inch wide.

The depth of the corrgations for a desired thickness of the metal was determined after considering the following factors: (1) the desired minimal breaking strength of the seal, (2) the fact that a maximum of thirty-five pounds pressure was desired as practical to be exerted upon the handles and (3) the desired hardness of the metal. Even higher strengths of the seals could be obtained by increasing the thickness of the clipped ma terial and decreasing the depth of corrugation but this could only be done at the expense of an increase beyond the desirable maximum in the requisite forces on 6 the handle and also of stresses on the tool which would exceed the practical limitations for a tool of this size.

In a form which has proved highly satisfactory, the seal is so made that in its open form its leg portions are connected to the back portion by an intermediate portion which has a radius of curvature of about, .06 inch. This has been found to give the best breaking strength for the seal and it is about twice the thickness of the seal material. If the radius of curvature is smaller than this, the seal pinches the edges of the strap when it is folded over and corrugated thereby weakening it in this region when tension is applied to the opposite ends of the strapping material. If the radius of curvature of this intermediate portion is made larger than .06 inch, contact may be lost at the end of the seal and it may not be possible to get proper closure of it.

It should be noted that, while the invention has been explained in terms of a mannual tool, it is equally adaptable to power-actuated automatic operation. It may also be adapted, if desired, to other forms of tools in which two-stroke operation is desirable. While the movable member 50 in the form of the invention shown herein on the in-stroke drives only the jaws which are also actuated by the outstroke of the handles, it is evident that other members could be either additionally or substitutionally driven by the movable member in response to the in-stroke.

Still other modifications and embodiments of my invention are possible which do not depart from the essence thereof and will occur to those skilled in the art from a reading of this application. Consequently, I desire my invention to be limited solely by the claims herein.

I claim:

1. Apparatus for applying a seal to strapping material comprising:

(a) means including mounting means to which a pair of levers and a pair of sets of jaws are mounted, said jaws being respectively coupled to said levers for producing a first deformation in said seal in response to the movement of said levers in a first direction,

(b) means including said sets of jaws for producing a second deformation in said seal in response to the movement of said levers in a second direction which is opposite to said first direction.

Apparatus for applying to strapping material a seal having leg portions joined to a back portion, said apparatus comprising:

(a) means including lever and jaw means responsive to the movement of said lever means in a single stroke in a first direction for folding said leg portions inward toward one another so that they lie substantially parallel to said back portion, and

(b) means including said jaw means and said lever means and being responsive to the movement of said lever means in a single stroke in a second direction opposite to said first direction for producting deformations in said seal, said (b) means also being constructed to snap said jaw means open substantially at the end of the movement of said lever means in said second direction.

3. Apparatus for applying a seal to strapping material comprising:

(a) first and second sets of opposed jaw members mounted for pivotal movement toward and away from one another,

(b) first and second handles coupled to said first and second sets of jaw members respectively for causing said sets of jaw members to pivot toward one another when said handles are moved away from one another,

(c) a plurality of stationary anvil members positioned to cooperate with said sets of jaw members to produce deformations in said seal,

(d) a plurality of linkage members coupled to said sets of jaw members,

(e) a member disposed for rectilinear movement toward and away from said anvil members, said moving member being coupled to said linkage members,

(f) means for biasing said movable member (e) away from said anvil members,

(g) a plurality of rigid members coupled to said handles and constructed and arranged to urge said movable member toward said anvil members against said bias only upon the movement of said handles toward one another thereby causing said jaw members, through the intermediary of said linkage members, to move toward one another and downward in the direction of said anvil members.

4. The apparatus according to claim 3 with the addition of first and second supporting plates disposed on opposite outer sides of said sets of jaw members, wherein said anvil members are coupled to said jaw members and to said supporting plates by a first pair of pivot pins about which said jaw members pivot, wherein a second pair of pivotpins pass respectively through ends of said jaw members remote from said first set of pivot pins, wherein said linkage members are coupled to said second pair of pivot pins, wherein said first and second handles are coupled by a third pair of pivot pins which respectively pass through said two sets of jaw members through apertures therein located betweensaid first and second pairs of pivot pins, wherein outer surfaces of said handles respectively make contact with said second pair of pivot pins when said handles are moved away from one another, wherein said rectilinearly-moving member is coupled by a single pin passing through it and through apertures in ends of said linkage members remote from the ends thereof through which said second pair of pins passes, wherein said biasing means comprises a spring having one end connected to said rectilinearly-moving member and its other end connected to said supporting plates, and wherein said rigid members (g) are pivotally mounted to said handles and biased so that their free ends are urged inward toward one another.

5. Apparatus for performing an operation upon an object comprising:

(a) means including a pair of levers and first deforming means coupled thereto for producing a first deformation in said object in response to the movement of said levers in a first direction, and

(b) means including said levers and said first deforming means and also including second deforming means for producing a second deformation in said object in response to the movement of said levers in a second direction opposite to said first direction, said (b) means being constructed and arranged to permit disengagement of said apparatus from said object once the production of said second deformation has commenced substantially only at the completion of the production of said second deformation.

6. The apparatus according to claim ll wherein said first deformation is produced by the movement of said sets of jaws in a predetermined direction and wherein said second deformation is produced by the movement of said sets of jaws even further in said predetermined direction.

7. Apparatus for fastening a seal having leg portions and a back portion to strapping material comprising:

(a) means including lever and jaw means responsive to the movement of said lever means in a single stroke in a first direction for folding said leg portions inward toward one another so that they lie substantially parallel to said back portion, said lever means including two handles pivotally connected to different ones of said jaw means, wherein pivot pins 8 3 pass through'said jaw means, wherein said handles have respective outer surfaces which urge. said pivot pins outward upon the outstroke of said handles thereby causing said jaw means to pivot inwardly toward one another, and

(b).means including said jaw means and said lever means and being responsive to the movement of said lever means in a single stroke in a second direction opposite to said first direction for producing corrugations in said seal and the portions of said strapping material contained therein thereby substantially preventing said material from movement therefrom, said corrugation-producing means including a plurality of linkage means connected to said pivot pins and means coupled to said linkage means and arranged for substantially linear movement toward and away from said jaw means, means for normally biasing said linearly-moving means in a direction away from said jaw means, and further whereinsaid'corrugationproducing means also includes two rigid projecting fingers connected to respective ones of said handles, said fingers being constructed to engage said linearlymoving means only during the instroke of said handles and thereby move it toward said jaw means, said projecting fingers being constructed to slide against-said linearly-movingmember on said outstroke but to engage notches in said linearly-moving means when engaging it during said instroke, said fingers further being constructed to be disengaged from said linearly-moving means substantially at the end of the said instroke thereby causing said moving member suddenly to'be urged away from said jaw means by said biasing means which in turn causes said jaw means to move away from one another to their original position at the start of the previous outstroke. V

8. Apparatus for fastening a seal having leg portions and a back portion to strapping material comprising:

(a) means including mounting plate means to which lever and jaw means are mounted, said jaw means being responsive to the movement of said lever means in a single stroke in an outwarddirection for folding said leg portions inward toward one another so that they lie substantially parallel to said back portion, and

(b) means including said jaw means and said lever meansand being responsive to the movement of said lever means in a single stroke in an inward direction for producing corrugations in said seal and the portions of said strapping material contained therein thereby substantially preventing said material from movement therefrom.

References Cited by the Examiner UNITED STATES PATENTS 1,354,150 9/20 Ward. 1,362,068 12/20 Wise. 1,897,511 2/ 33 Taylor 81-9.1 2,430,996 11/47 Rush 254109 2,524,654 10/50 Doolittle 81-9.1 2,833,170 5/58 Pachter 819.1 2,966,816 1/61 White 81-9.1 3,101,017 8/63 Malkin et .al.. 81-313 X FOREIGN PATENTS 444,847 8/12 France.

WILLIAM FELDMAN, Primary Examiner.

Claims (1)

1. APPARATUS FOR APPLYING A SEAL TO STRAPPING MATERIAL COMPRISING: (A) MEANS INCLUDING MOUNTING MEANS TO WHICH A PAIR OF LEVERS AND A PAIR OF SETS OF JAWS ARE MOUNTED, SAID JAWS BEING RESPECTIVELY COUPLED TO SAID LEVERS FOR PRODUCING A FIRST DEFORMATION IN SAID SEAL IN RESPONSE TO THE MOVEMENT OF SAID LEVERS IN A FIRST DIRECTION, (B) MEANS INCLUDING SAID SETS OF JAWS FOR PRODUCING A SECOND DEFORMATIONS IN SAID SEAL IN RESPONSE TO THE MOVEMENT OF SAID LEVERS IN A SECOND DIRECTION WHICH IS OPPOSITE TO SAID FIRST DIRECTION.

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