A crimping tool

(74) Agent

Pressmaster Tool AB, Box 3, S-796 01 Alvdalen, SE Mikael Nilsson, Alvdalen, SE

Mats Norin, Alvdalen, SE

Bryns Patentkontor AS, Oslo (54) Designation Press tools (56) Published publications None (57) Summary

A pressing tool comprises first and second jaws (1, 2) supported in a first pivot (5) for tear movement relative to each other. A front end of a first handle (6) is rigidly connected to the first jaw (1), while a front end of a second handle (7) is pivotally connected to the second jaw (2) at a second pivot point (8). A link structure (9) extends obliquely backward from a third pivot (10) located on the second handle (7) behind the second pivot point (8), up to a fourth pivot (11) on the first handle (6). The distance (D) between the first and second tipping points (5, 8) is 0.300.35 times the distance (A) between the first and second tipping points (5, 11), the distance (C) between the second and third tipping points (5). 8, 10) is 0.20-0.25 times the distance between the first and second tipping points (5, 11) and the distance (B) between the third and fourth tipping points (10, 11) is 0.62-0 , 66 times the distance (A) between the first and fourth tipping points (5, 11). In the closed position of the jaws (1, 2), a plane (E) comprising the second and third tipping points (8, 10) defines an angle (a) of 165-180 ° with a plane (F) comprising the third and the the fourth tipping point (10, 11), with the tip of the angle facing away from the first handle (6).

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The present invention relates to a pressing tool for, for example, manual pressing of electrical terminal contacts on ends of cables, and is of the type comprising first and second press jaws, each of which is provided with an individual press member and which is stored relative to each other in a first pivot for pivotal movement between an open and a closed press position, and comprising first and second handles intended for turning the jaws and extending backward from the jaws, wherein the first handle is rigidly connected to the first jaw at the forward end of the first handle while the second handle is pivotally connected to at least a portion of the second jaw at the forward end of the handle in a second pivot positioned behind the first pivot point, and wherein a link structure extends backwardly from a third pivot point on the second handle, behind the second pivot point, up to a fourth pivot point on the first handle.

Such tools (see, for example, GB-A-1522144 and DE-C-2555071) are widely used in the manufacture and installation of electrical and electronic devices. When using these known tools, it is necessary to exert relatively considerable force to complete the pressing operation in question, which results in the tool operator becoming tired and the risk of body load on the operator having to perform such operations regularly.

The present invention is based on the problem of providing a new and advantageous pressing tool of the type defined in the introduction, which construction is such that the tool will be significantly optimized from an ergonomic aspect, to at least substantially eliminate the problems associated with such tools.

In order to solve the aforementioned problem, it is proposed in accordance with the invention that the distance between the first and second^-the turning point is 0.30-0.35 times the distance between the first and fourth turning points, the distance between the second and third turning points is 0.20-0.25 times the distance between the first and fourth turning points, and the distance between the third and fourth turning points is 0.62-0.66 times the distance between the first and fourth turning points; and in that, when the jaws are in the pressing position, a plane comprising the second and third pivot points defines an angle within the range 165-180 ° with a plane comprising the third and fourth pivot points with the tip of the angle facing away from a plane comprising the first and the fourth turning point.

Another object of the invention is to provide a flat tool constructed of flat parts, to provide a pressing tool capable of gripping objects, such as a cable end and cable shoe to be pressed on the cable end, so that a two-handed grip can be used if desired, and provide a pressing tool equipped with an improved marking device to indicate that the shrink tool movement is complete. These and other objects described in the following description are achieved with the pressing tool having the characteristic features set forth in the dependent claims.

The invention will now be described in more detail with reference to selected embodiments thereof and also with reference to the accompanying drawings.

Follow. 1-3 illustrate schematically and in side elevation, respectively, a first, second and third embodiment of the crimping tool according to the invention.

Follow. 4-6 are respectively a bottom view, a side view and a top view of a fourth embodiment of the pressing tool according to the invention.

Fig. 7 is a side view of a fifth embodiment of the pressing tool 1 according to the invention.

FIGS. 8 and 9 are central longitudinal sections on an enlarged scale of a section of the tool of FIG. 7 is provided with a marking device which prevents interruption of the starting tool movement before the movement is completed.

10 and 11 are views similar to the views of FIG. 8 and 9 illustrating alternative embodiments of the marking device.

All identical or substantially identical tool elements shown in the drawings are identified by the same reference numerals.

Fig. 1 illustrates a closed pressing tool comprising first and second jaws 1, 2 which are intended to be jaw inserts which function, for example, to press terminal contacts on electrical conductors. Such jaw inserts are shown only in FIG. 3 and has here reference numbers 3 and 4. The jaws 1 and 2 are supported in a first pivot 5 relative to each other between the illustrated, closed position and an open position (not shown) allowing, for example, a cable end and a terminal contact to be pressed on the cable end and inserted between inserts 3 and 4 in the open jaws. The tool also includes first and second handles, generally with reference numerals 6 and 7, respectively, extending backwards from the jaws 1, 2. Each handle comprises a metal handle body 6a, 7a which, in the areas to be held by the user during a pressing operation, is equipped with outer pull or outer handle 6b, 7b, which is made of, for example, plastic material and has an easy-to-grip shape. The first handle 6 is rigidly connected to the first jaw 1. In the illustrated embodiment, a protruding portion of the handle body 6a forms a rear portion of the jaw 1 and the first pivot point 5 is located on this part of the handgrip body. The second handle 6 is pivotally connected to the second jaw 2 by means of a second pivot point 8 located at a forward end of the handle, whereby the second pivot point 6 is located behind the first pivot point 5. A link structure 9 extends obliquely backward from a third pivot 10 located on the second handle 7 behind the second pivot 8, up to a fourth pivot 11 on the first handle 6.

In order to provide a pressing tool with substantially optimal ergonomic properties, the distance D between the first and second pivot points 5, 8 is 0.30-0.35 times, suitably about 0.32 times the distance A between the first and second pivot points 5, 11, whereas the distance C between the second and third pivot points 8, 10 is 0.20-0.25, and suitably about 0.24 times the distance A, and the distance D between the third and fourth pivot points 10, 11 is 0.62-0.66 , conveniently about 0.64 times the distance A. In the closed position of the tool, a plane E extends perpendicular to the firing plane and comprising pivots 8 and 10 defines an angle α within an angular range of 165-180 ° with “one plane F comprising pivots 10 and 11, with the tip of the angle facing away from a plane G comprising pivots 5, 11.

As is the case with the illustrated embodiments, the tool hand bodies 6a, 7a are mutually disposed in the same plane, and the joint structure 9 consists of two similar planar and mutually identical articulated arms, each located on a respective side of the handle bodies and of which the articulation arm is placed closest to the viewer. FIG. 1-3 and 5 and 7 hide the articulation located behind the articulation visible in the drawings. A section 7ac (fig. Advantageously, 2, 8, 10, 11) of the second handle body 7a located behind the third pivot point 10 may be positioned between and extending substantially parallel to the two articulated arms of the articulated structure 9 in the closed press position of the tool. The handle body 7a is then curved to extend substantially parallel to the first handle 6. The first section 7ac has substantially a length in the order of half the distance between pivots 10 and 11. This arrangement, especially in combination with the location of the pivot point 8 behind the pivot point 5 in the closed position of the tool, allows selection of the distance between the handles 6 and 7 so that it becomes particularly advantageous from an ergonomic aspect both in the open position and the closed position of the tool.

10 The first jaw 1 comprises two plates 1c which are firmly connected to a respective side of the handle body 6a (see in particular Fig. 4) and between which a pressing member (Fig. 3) is intended to be attached. Similarly, the second jaw 2 comprises two plates 2c, each located on a respective side of i? the handle bodies 6a and 7a, (see especially Fig. 6) and which are supported for rotational movement relative to both the body 6a and the body 7a and between which a pressing member 4 (Fig. 3) is intended to be attached. The construction of the tool components in the form of flat or plate-like elements is preferable from a mechanical strength aspect. As can be seen from FIG. 4 and 6, the handle body 6a, 7a may be constructed from²two flat portions 6aa, 6ab and 7aa, 7ab located side by side at a small distance from each other.

Reference numeral 12 in FIG. 1 identifies a tension spring which acts to rotate the jaw 2 counterclockwise around pivot point 5, thereby turning handle 7 clockwise around pivot point 11 unless handle 6, 7 is pressed against the tool's closing position. To prevent, in known manner, interruption of³⁰ the pressing operation before the jaws 1, 2 are pivoted to the fully closed position, or to prevent interruption of the tool opening movement, the handle 7 is provided with a toothed ring portion 13 which is concentric with the point 10 and intended to cooperate with a locking pallet 15 rotatably mounted on the articulated cone.³³ structure 9, which is pivotal to the action of a tension spring 14. It should be understood that pallet 15 must be positioned either in front of or behind the toothed ring portion before the tool can be closed or opened. Such an arrangement is illustrated and described in, for example, the patent descriptions mentioned in the introduction.

To enable adjustment of the jaws to a desired closing position and adjusting the tool's closing position when the tool is worn, one of the storage pins in the pivot points is, appropriately, the pivot pin in the pivot point 10 fitted in a known manner (not illustrated here) with a cylindrical portion. stored centrally in a handle body and two cylindrical portions located on opposite sides of the central portion and which, depending on the position of the bearing pin, are supported in two joint arms in the joint structure 9 or in the plates 2c of the jaw 2 and which are mutually coaxial but eccentric with respect to the central part. The bearing pin for adjusting the desired jaw closing position is thereby rotatable and lockable in the set rotational position. Such an arrangement is illustrated and fully described in, for example, the patent descriptions mentioned in the introduction.

The tool illustrated in FIG. 1 is automatically opened at the tension spring 12. When performing a pressing operation, the article to be pressed, for example, a terminal contact inserted at the end of a stripped cable end, is inserted between the pressing portions 3, 4 of the fully open jaws 1, 2 (not shown in FIG. 1), after which the handles are pivoted to one another while manually holding the objects between the jaws until the pallet 15 is behind the toothed ring portion 13, thereby completing the pressing operation. It is understood that the joint structure 9 and the pivot handle 7 form a knee mechanism which, when the handle 7 is rotated counterclockwise with moderate force, causes the second jaw 2 to rotate clockwise with a greater force during the pressing operation. In order to avoid damage to the tool, the tool will preferably have a certain degree of yield, while at the same time ensuring that the necessary compressive force is achieved. Preferably, the tool will have its own elasticity so that the jaws 1, 2 can be pivoted apart at an angle

X- 'of 5 *, preferably an angle of about 10 °, from a closed pressing position provided by the handles 6, 7, without any permanent deformation of the tool. Correspondingly, the handles 6, 7 must be able to pivot to the closed position without any permanent deformation of the tool, although an incompressible object between the jaws 1, 2 keeps the jaws obliquely apart at an angle of up to 5 ° or 10 °, respectively.

Fig. 2 illustrates a tool embodiment which allows an object, for example a terminal contact, to be held clamped between the pressing portions 3, 4 of the jaws 1, 2 before the handles 6, 7 are pivoted against each other, for example, so that the handles can be pivoted against each other by a two-handed grip. To achieve this, the press jaw 2 comprises a first jaw member 2a in the form of an articulated arm extending between the pivot points 5 and 8 and a second jaw member 2b which is intended to be the press member 4 and which is supported in the pivot point 5. A compression spring 16 acting between the jaw members 2a and 2b operate to pivot both jaw member 2b and handle 7 clockwise about respective pivot points 5 and 10. A bearing pin mounted at the pivot point 8 protrudes on both sides of the handle 7 and is intended to be received in recesses 17 in jaw portion 2a, at least at the end of the pressing operation. The tool illustrated in FIG. 2 will thus normally assume the position shown in the figure. An object is clamped between the jaws by pressing down the jaw portion 2b in the direction of the arrow 18 against the action of the spring 16, whereby the object is inserted between the jaws and the jaw portion 2a allowed to swing back toward the closed position. The handle 7 is then pivoted counterclockwise against the action of the spring 16, whereby the bearing pin extending through the pivot point 8 gradually engages the recesses 17 and pivots the jaw portion 2b to the fully closed position, in which the locking pallet 15 is positioned behind the toothed annular portion 13. with respect to the tool, the tool is constructed in the manner described with reference to FIG. 1. The rear end of the articulation arm 2a is received in a space between the portions 7aa, 7ab forming the handle 7 (FIG. 6).

The tool illustrated in FIG. 4 is constructed in a similar manner to the tool illustrated in FIG. 1, except that a compression spring 16 acting between the handle 6 and the jaw 2 strives to keep the tool closed. The tool is fully opened by applying pressure in the manner indicated by arrow 18, after which, for example, a terminal contact is clamped by insertion of the terminal contact into a corresponding recess 19a, b or c in the pressing portions 3, 4 and then the jaw 2 is allowed to is pivoted back to closed position under the action of spring 16. The pressing operation is then completed by moving the handles 6, 7 against each other until the locking pallet 15 is positioned behind the toothed ring part 13.

Figs. 4-6 illustrate the tool construction method when the handle bodies are in the form of double surface elements 6aa, 6ab and 7aa, 7ab. It will also be seen that the jaws 1 and 2 are constructed from plate-like elements 1c and 2c. In other respects, the tool is illustrated in FIG. 4-6 constructed in the same manner as described with reference to FIG. 1.

FIG. 7 illustrates a closed press tool similar to the tool illustrated in FIG. 4 to 6. The tool of FIG. 7 is provided with a marking device 21 to 26 which, similar to the aforementioned elements 13 to 15, can be adapted to prevent pivoting of the handles 6, 7 in one direction before a pivotal movement of the handles in an opposite direction is completed. The construction of this type of marking device is shown in detail in FIGS. 8 to 10, while FIG. 11 shows a marking device which, although indicating that a tool movement is complete, does not prevent interruption of the tool movement before its completion. In the tool of FIG. 7, thus preventing the tool marking device 21 to 26 from interrupting the pressing operation before the jaws 1, 2 are pivoted to fully closed position and preventing the interruption of a tool open movement, the articulated arms of the articulation 9 are provided with parts 20 with chamber 21. These ridges have a abruptly decreasing height at their ends and a toothed cam surface 22 between them which is arcuate 5 deflected with the center of the arc at point 10, which is clearly shown in FIG. 8 and 9. Each cam 21 cooperates with a cam carrier 24 mounted in a generally V-shaped slot 25 formed in a portion 23 of the handle body 7a and projecting from both sides of the handle body. A spring 26 acting between¹⁰ the cam burner 24 and the point or pin 10 strive to pull the cam burner into the bottom portion of the V-shaped slot. It will be appreciated that the cam driver 24 must be positioned in front or behind the ends of the combs 21 before the tool can be opened and closed, respectively, as is also clearly evident.¹5 can be seen from the above description of the elements 13 to 15. The legs of the slot 25 extend obliquely away from the cam surface 22. When the portion of the portion 23 carrying the slot 25 is positioned between the ends of the cam surface 22, the cam 21 covers the bottom portion of the slot 25. Thus, as the portion 25 moves to the left of FIG. 8, the cam driver 24 of the chamber portion is inserted into the rear leg, as seen in the direction of motion.

The cam driver 24 is kept in constant contact with the cam surface 22 by the action of the spring 26. When the movement is complete, the cam driver 24 leaves the cam surface 28 25 and snaps into contact with the bottom portion of the V-shaped slot 25, thereby allowing the arrangement to be constructed achieves a visual indication or mark when the movement is complete. Optionally, the described arrangement may be constructed such that the position of the cam carrier cannot be seen 50 when the movement is complete, or only difficult to see. In this regard, the indication can only be an acoustic indication, that is, the indication is given at the click sound made when the cam dispenser 24 snaps into contact with the bottom portion of the slot 25. As the part 23 is moved back to the right in FIG. 9, 55, the cam driver 24 is inserted into the now rear slit leg. Finally, when the cam driver passes longitudinally along the entire cam surface 22, it snaps back into the bottom portion of the slot 25 in the manner shown in FIG. 8.

The tool illustrated in FIG. 7 is automatically opened by the tension spring (not shown) acting between the jaw 2 and the handle 6. When performing a pressing operation, the relevant objects, such as a terminal contact to be pressed on the stripped end of a cable, are passed between the press parts (not shown ) supported by the fully open jaws 1, 2, the handle 7 is pivoted upward from the position illustrated in FIG. 7 in the manner illustrated in FIG. 9. While holding the objects manually in position between the jaws, the handles 6, 7 are pivoted against each other until the slot 25 is positioned in front of the cam surface 22, as shown in FIG. 8, whereby the pressing operation is completed.

As previously mentioned, FIG. 8 and 9 are central longitudinal sections of the indicating device in the tool according to FIG. 7. The incision is taken such that between the body parts of the handle 7 so that only body part 7ab and one of the articulated arms 9 located below it are visible. Both this body portion 7a and the upper body portion (not shown in Figures 8 and 9) are provided with mutually opposite slots 25. The cam driver 24 extends through the two slots and the opposite ends of the cam driver interact with respective toothed cam surfaces 22 on each of the portions 20 of the articulated arms. The spring 26 is positioned between the reciprocal cover body portions 7aa, 7ab and is thus completely protected by these. As can be seen particularly clearly from FIG. 7 and 8, the section 7ac of the handle 7 and the handle body 7a, respectively, located adjacent the shaft or point 10 extend substantially parallel to the articulated arms 9. This arrangement in combination with the selected reciprocal relationships between the spacing of the pivots 5, 8, 10, 11 results in a moderately ergonomically advantageous distance between the handles 6 and 7, both in the open and closed positions of the handles. As can be clearly seen in FIG. 5 and 7, the handle cover 7b is extended forwardly to cover the tipping point or link 10 which, as described above, is suitably connected to means for setting a desired closing position for the jaws 1, 2 and adjusting the closing position when the tool is worn.

Figs. 10 and 11 are views similar to Figs. 8. However, the cam 21 is mounted on the handle body 7a, while U-shaped slots 25 are provided in the link structure 9. The cam carrier 24 is inserted at opposite ends thereof into the slots 25 in the link members 9, while the center portion of the cam carrier is intended to cooperate with the cam 21 on the handle body. 7a located between the articulated arms. The respective sections in FIG. 10 and 11 are taken in the same way as the sections in FIG. 8 and 9, and consequently only the lower articulated arm and body portion 7ab located closest to it can be seen. The spring 26 acting between the cam driver 24 and the pivot pin 10 is completely protected between the body parts 7aa, 7ab. The cam surface 22 in the embodiment of FIG. 10 is toothed and operates in the manner described with reference to FIG. 7 to 9, while the cam surface of the embodiment of FIG. 11 is smooth and does not prevent reversal of tool movement until complete.

This invention is not limited to the above-described and illustrated embodiments, but can be realized in any desired manner within the scope of the inventive concept defined in the appended claims.