The invention relates to a crimping tool with crimping dies, the crimping dies being arranged in a star-like layout directed toward a crimping region and being rotationally acted on, at a radially outward location, for the crimping movement, by means of an activating part, the crimping dies, furthermore, being mounted for pivoting-in about a pivot axis transverse to their longitudinal extent and forming an abutment region on the crimping-region side of the pivot axis.
Such a crimping tool is known, for example, from EP 0 732 779 B1. In the case of the known crimping tool, the crimping dies are illustrated as being in abutment against one another in each case in their abutment region. This is also a preferred state. The geometrical edge conditions, however, mean that, during the pivoting-in movement and also at the end of the pivoting-in movement, there is a relatively large gap between crimping-die surfaces which are associated with one another in the crimping region. Relatively large here means that, during a crimping operation, this can give rise to undesired distortion in the crimping region, i.e. penetration or bulging-out of the crimped article into the gap. This can result in problematic formations of the crimping region of a crimped wire end for example, the desire being for this crimping region to be, as far as possible, precisely angular corresponding to the crimping surfaces. As far as prior art is concerned, reference is also made to U.S. Pat. No. 5,261,263 A1.
Taking the disclosed prior art as a departure point, it is an object of the invention to provide a crimping tool for which, during a crimping operation, as far as possible no gaps occur between the crimping dies.
Further aspects are given in respect of further features of the invention as are explained hereinbelow. They may be important in their own right, or on a substitute or supplementary basis, in relation to the object which has already been mentioned.
A possible solution for achieving the object set out above is provided, according to a first concept of the invention, by the subject matter of claim 1, this being based on the fact that the rotational movement of the crimping dies is accompanied by a radial movement and/or circumferential movement, for the purpose of achieving abutment of a crimping die, in its abutment region, against the counter-abutment region of a crimping die which is adjacent to this crimping die in the direction of pivoting or the direction counter to this. A crimping die is thus not only pivoted. It is addition also moved radially. As an alternative, or in addition, a circumferential movement may be provided, for example in that the (current) pivot point of the crimping die is shifted in the circumferential direction during the pivoting movement. Since the movement, in particular the radial movement, is controlled, for example by appropriate cam features, allowances can be made for the geometrical edge conditions, which result in the gap formation, as explained.
The crimping dies form, in the radially inward direction, a crimping space which decreases in size during the crimping movement. The crimping space is ideally a space with a circular cross-section. In reality, this is approximated by a polygonal cross-section. This crimping space, accordingly, gives rise to a polygonal cross-section of the workpiece which is to be crimped. The described abutment of the crimping dies gives rise to effective closure of this crimping space, at least in the critical phase of the pivoting movement of the crimping dies, when the workpiece is subjected to plastic deformation. As a result, a workpiece is prevented from penetrating into the abutment gap between the crimping dies. The workpiece is prevented from escaping out of the polygonal cross-section.
According to a further concept of the invention, it may be provided that the crimping die is formed in the manner of a link or can be pivoted with link guidance about a pivot axis outside its longitudinal center. This embodiment is based on the general teaching of finding the largest possible radius for the pivoting movement of the crimping die. The link guidance or link formation makes it possible to achieve the situation where the center point of rotation of the pivoting movement of the crimping die is advantageously shifted outward, possibly also beyond the radially outer end of the crimping die, and possibly beyond the housing. A large pivoting-movement radius can be achieved in that the variable gap width in the possible abutment regions which, in the absence of other measures, is necessarily established during pivoting of the crimping dies, remains small enough for it to be possible to avoid the situation where the workpiece undesirably escapes out of the crimping space into gaps which come about.
The features of the two possible solutions mentioned above may also be combined with one another.
Further features of the invention will be explained hereinbelow, also in the description of the figures, often in their preferred association with one of the claims already mentioned, but they may also be important in association with just one or more individual features of one of these claims or also independently.
A feature which is described as preferable can be considered as being only preferable—and not mandatory—even when another context makes reference to this without expressly emphasizing that such an embodiment is merely a preference. It is also the case in this other context that correspondingly, in addition to the more specific feature, the more general feature is also disclosed without this having to be repeated in the wording.
It is thus preferred if the radial movement is assisted by an energy store. This energy store, further preferably, is provided such that it constantly advances or biases the crimping die into the radially innermost position.
In a suitable, more concrete embodiment, the energy store may be provided by a spring.
Furthermore, it is preferred if a crimping die is accommodated in the radially outward direction in a positively locking pocket for rotational activation, and if the positively locking pocket has an oblique surface which interacts with a circumferentially oriented control extension of the crimping die such that the crimping die is moved radially.
In respect of the already mentioned link guidance, it may be provided that the crimping die is actuated by means of a link which is secured in a pivotable manner, on the one hand, to the crimping die and, on the other hand, to the activating part.
The link can be supported on the activating part, in particular, radially outside a radially outer end of the crimping die. It is also preferred if the link is supported on the crimping die radially outside the pivot axis of the crimping die. On the other hand, it is also possible to have a configuration in which the link is supported on the crimping die radially inward of the pivot axis.
It is particularly preferred, furthermore, if two links are provided, one of the links being supported, on the one hand, on the crimping die and, on the other hand, on a fixed bearing. The other link can then be supported on the activating part, so that the pivoting movement, and possibly radial movement, is achieved in this way.
Furthermore, it may preferably be provided that the crimping die, for the purpose of forming a virtual pivot axis, is guided by means of two fixed pivot pins which interact with slots. It is possible here for the fixed pivot pins to be provided on the crimping die and for the slots to form part of the housing. It is just as possible for this arrangement to be the other way round.
It is also possible for the fixed pivot pins to be provided on the crimping die and for the slots to form part of the housing, but, in relation to a pivoting axis of the crimping dies, to be provided on either side.
The crimping die itself may also be mounted for pivoting at its radially outer end region by means of a bearing pin accommodated in it. The end region here, in particular, is a radially outer third of the crimping die or a smaller part thereof, for example a quarter or a tenth of the overall radial extent of the crimping die. Furthermore, it may be provided that a crimping die, upon rotation in the pivoting-in direction, interacts with a control pin disposed between its end regions, that is to say the radially outer end region and the radially inner end region, by virtue of relative displacement in the longitudinal direction (radial direction). The end regions here are the same regions as those explained above in respect of the radially outer end region. The possible lengths mentioned, however, need not always be the same. There is therefore no need for a third of the length for the end region in the radially outward direction to correspond to a third of the length for the end region in the radially inward direction. The control pin accordingly performs, as it were, a stop function for the crimping die in the relevant direction and, at the same time, also an aligning function.
The control pin may preferably be disposed outside the crimping die. However, it may also be disposed within the crimping die, for example in a slot formed therein.
Furthermore, it is preferred if a surface of interaction which is formed on the crimping die for interaction with the control pin is curved. This curvature is “experienced” by the control pin as it moves along the crimping die during the aforementioned relative movement.
A further preferred embodiment, which is important, in particular, independently of a possible radial movement and/or a circumferential movement and/or of link guidance of the crimping dies, is realized in that the crimping dies are formed to interengage in their abutment region. This can be achieved in that the crimping dies interengage in a comb-like manner, that is to say in a plurality of layers. This also makes it possible to counteract the undesired influencing of the crimping result by gap formation.
A still further preferred embodiment, which is important at any rate, in particular, independently of a possible radial movement and/or circumferential movement and/or link guidance of the crimping dies, is realized in that the crimping dies are activated for movement in the radially inward direction as a linear movement and, over part of their movement, are displaced radially inward in abutment against one another in an abutment region. This part of the movement is, in particular, a final part of the movement in the radially inward direction, for example a tenth or more of the overall movement. Abutment of the crimping dies against one another can also be present over a third or a half of the movement or also throughout the entire movement. The aforementioned range, between a tenth of the movement and the entire movement, also includes any intermediate value, in particular in one-tenth increments, in relation to the overall length of the movement in the radially inward direction. In particular, it is preferred if the linear movement in the radially inward direction is accompanied by movement in the circumferential direction. This can be suitably provided, for example, by slots which are formed on the underside or upper side of the crimping dies, interacting with a fixed plate, and have a corresponding portion in the circumferential direction, fixed pins then running in these slots. This arrangement can also be provided the other way round in respect of fixed and moving elements.
As far as the construction of the crimping tool is concerned, it is possible to provide a lower plate which forms a base plate. In particular, it is possible for the lower plate to be fixed to a central guide protrusion or even to be formed in one piece therewith. This makes it possible to achieve central guidance of the rotary plates, and also central guidance of the crimping dies themselves, in particular in the cases where the crimping dies, which execute a pivoting movement and a longitudinal movement, are no longer sufficiently centered by their actual bearing location, in respect of the crimping region.
In particular, the plate which is referred to here as the carry-along plate is preferably guided by the guide protrusion.
The invention will be explained in more detail hereinbelow with reference to the accompanying drawing, although the latter illustrates merely exemplary embodiments of the invention. In the drawing:
a-12c show individual plates for constructing the tool according to
d-12f show a movement sequence during crimping using a tool according to
The basic construction of a crimping tool on which this invention is based will be illustrated and described, in first instance with reference to
In this respect, reference is also made to EP 0 732 779 B1, which has already been mentioned in the introduction and the content of which is hereby included in full in the disclosure of this application, also for the purpose of incorporating one or more features of the reference document in claims of this application.
The crimping tool in question here basically has handle parts 1 and 2. The handle part 2 is a movable handle part. It can be rotated about the axes 3 and 43, with a toggle being formed in the process. A toggle action is also achieved here. Connection to a carry-along (drive) plate 4 is also realized via the axis 3, positively locking pockets 5 being formed in this carry-along plate for ends 6 of the crimping dies 7. The crimping dies are driven by rotation of the carry-along plate 4.
A crimping die 7, furthermore, is mounted about a pivot axis 8 for pivoting-in purposes. The pivot axis 8 extends transversely to a longitudinal extent of a crimping die 7.
On the crimping-region side of the pivot axis 8, a crimping die 7 has an abutment region 9, which is directed counter to the direction of pivoting. In addition, a crimping die has, in a pivoting direction, a further, counter-abutment region 10, against which, in turn, an adjacent crimping die butts. It is preferred if at least the abutment region 9, as far as possible, is closed, i.e., in particular in the event of relatively high forces being applied, only a small gap, or no gap at all, is formed. The counter-abutment region 10 forms, in the direction of the center, to the extent that it is not covered by the abutment region 9, the crimping region.
According to one embodiment, the abutment surfaces of the crimping dies, which form the abutment region 9, are planar and/or, as seen in a projection as in the figures of the drawing, are rectilinear. However, they may also be curved to match one another, for which purpose reference is made, for example, to the embodiment of
For the purpose of achieving an action-influencing component which acts constantly in the radial direction and/or circumferential direction, and accompanies the pivoting movement, a spring 11 or 12 is provided in the case of the exemplary embodiments of
On the other hand, it is also possible, possibly in interaction with the supporting surface in the positively locking pocket, to have a central arrangement for a spring, as is the case with the spring 12 in the embodiment of
Accordingly, it is possible for the springs to enclose, in their direction of action, an angle alpha of between 0° and 90° with the axis A.
In order to achieve the desired abutment of a crimping die 7, the pivot axis element 8 is accommodated in a slot 36. As is evident, the slot 36 has a direction of extent, or at least an extent component, in the radial direction and/or circumferential direction. A slot 36, further preferably, has a direction of extent which runs in the direction of action of the spring. Furthermore, it may also have a direction of extent which runs both through the spring and through the axis 8. Depending on the magnitude of the angle alpha, however, the direction of extent of the slot 36 may also coincide with the axis A.
In the case of the embodiment of
In the case of the embodiment of
In the case of the embodiment of
The embodiment of
The mounting of the crimping dies on the pivot axis element 8 gives rise, during the pivoting-in movement, to a certain upstanding action by the link 15, and this action, since, as is evident, it is also established on the far side of the link axis, as seen in the pivoting direction, in relation to the longitudinal axis A, provides for the desired activating component. This gives rise to the abutment action in relation to a crimping die which is adjacent in the direction counter to the pivoting direction of the respective crimping die 7. In specific terms, the link 15 is provided here such that, at least at the beginning of the pivoting-in movement of the crimping dies 7, it is inclined in the direction of rotation of the plate 4 and then becomes appropriately upstanding. This means that, as seen in the direction of rotation of the plate 4, the bearing point of the link 15 in the plate 4 is formed before the bearing point of the link 15 in the crimping die 7. An angle which is formed by the longitudinal axis of the crimping dies and the axis of the link decreases in size as the closing movement increases.
The subject matter of
In the case of the embodiment of
In the case of the embodiment of
More specifically, in the case of the embodiment of
To provide further explanation, the essential elements are also illustrated in
An identical base plate 37 is disposed opposite, also as an outermost plate in respect of the combination of plates described here.
A cam plate 27, or preferably a respective cam plate 27, is provided above and beneath the plate 37, and these cam plates are fixed to the respective plate 37 by means of rivets passing through the bores 39. The cam plate 28 is disposed in the center, the rivets running through slots 40 in this cam plate 28. The latter cam plate, which is used here, for all practical purposes, only for rotation, has more or less rectangular openings 41 which meet in the center and, in this case, serve for carrying along the crimping dies of matching shape that are seated therein.
The cam plate 28 has a drive portion 44, configured preferably as a drive tube, via which driving takes place by way of the movable handle part 2. The two plates 37 are connected to the fixed handle part 1.
In respect of the cam plates 27,
The exemplary embodiment of
The interengagement of the crimping dies is important in the case of the embodiment of
By virtue of the pivoting movement of the rotary plate 35, the crimping dies are moved along the cam plate and driven by this, so that they execute a linear play-free movement.
As is quite evident from
The crimping dies have slots 41, in which run the pins 33, which are fixed to the housing. The slots 41 extend in the axial direction A of the crimping dies 7. The crimping dies 7, furthermore, are biased toward the pins 33, by springs 42, in the slots 41, to be precise such that a respective crimping die 7 is forced radially outward as a result.
In the case of the embodiment which is illustrated in
Furthermore, in the case of this embodiment, a crimping die 7 interacts with a control pin 44. The control pin 44 is fixed. A pivoting-in movement, in arrow direction P of the carry-along plate 4, gives rise not just to a pivoting movement of the crimping die 7 about the control pin 44, but also to a certain relative movement. In terms of the crimping die being curved throughout, the control pin 44 is disposed on the inner side of the curvature. It is also the case that the control pin 44 has a surface of interaction with the crimping die 7, and this surface is curved. The surfaces here differ in curvature. The crimping die 7 moves in the radially outward direction relative to the control pin 44 during this pivoting-in movement. Since, further preferably, the surface of interaction on the associated outer side 45 of the crimping die 7 is formed with a certain degree of curvature in such a way that the curvature is in the plane of the drawing, this makes it possible for the crimping die to be acted on so as to enable the crimping die to be guided in a controlled manner, to be precise, in the present context, it allows controlled guidance in respect of gap minimization. Of course, this control surface or all four control surfaces of the crimping dies 7, of which there are four in the case of the exemplary embodiment, have to be formed, and coordinated with one another, so as to achieve the desired gap minimization.
The specific construction is evident from the cross-sectional illustration according to
The control pins 44, of which only one can be seen in
The embodiment of
All features disclosed are (in themselves) pertinent to the invention. The disclosure content of the associated/attached priority documents (copy of the prior application) is hereby also included in full in the disclosure of the application, also for the purpose of incorporating features of these documents in claims of the present application.
Number | Date | Country | Kind |
---|---|---|---|
10 2008 031 346.7 | Jul 2008 | DE | national |
10 2009 004 209.1 | Jan 2009 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2009/058366 | 7/2/2009 | WO | 00 | 12/29/2010 |