Hand pliers designed for crimping and hand pliers with one head

Description

field of technology

[0001] The invention relates to a hand-held crimping tool designed for carrying out crimping, comprising a fixed and a movable pliers arm, as well as a first and a second crimping jaw, wherein the first crimping jaw is actuated by a drive plunger. State of the art

[0002] Hand pliers of the type in question are known, in particular for use as so-called crimping pliers for crimping or pressing together components, such as wire ferrules onto stripped ends of electrical cables. Reference is made, for example, to DE 10 2018 101 159 A1.

[0003] Furthermore, hand pliers are known that are specifically designed as pliers-like wire stripping tools, but also allow for crimping, for example, the previously stripped cable end with a wire ferrule using the same tool. Such a hand tool is known, for example, from EP 0 540 880 B1 (US 5 500 998).

[0004] From EP 3 396 796 A1, a pressing, crimping or cutting tool according to the preamble of claim 1 is known, in which, for example, a crimping jaw is supported in a mechanical parallel connection via an elastic support element and a sensor. The highest possible stiffness is nevertheless desirable.

[0005] US Patent 5,042,286 A discloses a pliers-like hand tool designed as a crimping tool, in which a movable crimping jaw is linearly movable relative to a stationary crimping jaw for crimping. According to one embodiment, a locator can be provided associated with the stationary crimping jaw, wherein the locator is movable against a compression spring.

[0006] US patent 2019 / 0312397 A1 discloses a hand crimping tool with one fixed and one pivoting crimping jaw. The tool is designed solely for crimping. Summary of the invention

[0007] Based on the prior art presented, the invention aims to advantageously design a hand tool as described above in a way that is favorable from a handling perspective.

[0008] This problem is solved in the subject matter of claim 1, wherein the first and second crimping jaws are provided with partially comb-like interlocking ribs which, looking towards the insertion direction of a cable provided with a crimping piece into a crimp opening, are triangular in shape, resulting in a rectangular crimping jaw in plan view in an unloaded basic position, the second crimping jaw is retractable against spring force in a crimping jaw receptacle of the hand pliers, and the first and second crimping jaws are arranged in a common linear guide.

[0009] The spring force can be applied directly by the second crimping jaw, in particular by a section of the second crimping jaw, or alternatively by a separate component. For example, the second crimping jaw can have a corresponding spring element, which may be integrally formed, either directly or indirectly. Furthermore, the spring element applying the spring force can be a separate component from the second crimping jaw, such as a metal or plastic spring, e.g., in the form of a cylindrical compression spring or a torsion spring. A plastic spring in the form of an elastically compressible solid element, for example, a foam element, is preferred. A polyurethane block element can also preferably serve as the spring element against which the second crimping jaw acts, particularly during crimping.

[0010] The spring-assisted return or deflection of the second crimping jaw during crimping allows for the crimping of crimps with varying dimensions (and possibly diameters) in the direction of displacement, while maintaining a substantially constant displacement path of the movable pliers arm, which acts on the first crimping jaw, preferably indirectly via the drive plunger. This results in an at least approximately constant actuation path for the hand pliers, particularly for the user, regardless of the diameter of the crimped component, such as a wire ferrule. The varying displacement paths, especially of the first crimping jaw, which depend on, for example, the diameter of the crimped component, are made possible by the second crimping jaw, which can be moved back against the spring force. The spring preferably compensates for these displacements.

[0011] Furthermore, due to the spring action on the second crimping jaw, it is moved back into a potentially stop-limited home position after crimping has been performed and the first crimping jaw has been moved back. A coupled dragging of the second crimping jaw via the first crimping jaw for the return movement of the second crimping jaw is unnecessary.

[0012] With normal handling of the crimping pliers, a crimping area is created, which is assigned to either the underside or the top of the pliers. In this way, a cable with a ferrule attached to one stripped end can be inserted into the crimping area of ​​the pliers from the underside, with the cable end pointing essentially vertically upwards and the ferrule attached. The desired crimp is then achieved by operating the pliers in a pinch-like manner. The pliers are in their normal, standard position throughout the process.

[0013] According to the invention, the first and second crimping jaws are arranged in a common linear guide. The linear guide can optionally also serve as the crimping jaw receptacle for the second crimping jaw. The drive plunger, preferably connected to or acted upon via the movable pliers handle, preferably exerts a linear displacement effect on the first crimping jaw. During crimping, the second crimping jaw can optionally also be displaced against the spring force within the linear guide via the first crimping jaw and the crimped part. The linear guide can be formed directly within the hand pliers, particularly within the housing of the hand pliers, by means of a design element.With reference to a cross-section transverse to the linear displacement direction of the first crimping jaw, for example, a lateral guide on both sides of both crimping jaws can be obtained, more preferably a guide that substantially surrounds the entire circumference of the crimping jaws.

[0014] In a further embodiment, the hand pliers are designed as wire strippers, whereby the same hand pliers can first be used to strip a free cable end and then to crimp this stripped cable end with, for example, a wire end ferrule.

[0015] To ensure, in particular, complete crimping, i.e., completion of the crimping process, and / or any stripping process, the plier handles can interact via a positive locking mechanism, according to one possible embodiment. This positive locking mechanism preferably allows the movement, especially pivoting movement, of the movable plier handle only in one direction during plier operation, namely preferably the closing direction, until the plier handle reaches a position in which the crimping and / or stripping is reliably completed. Only then does the positive locking mechanism, preferably without any further additional action by the user, release the movable plier handle to return to its home position, and thus, in particular, the first crimping jaw to its home position.

[0016] In a further embodiment, the forced locking mechanism can also be manually released by the user after initiating a crimping or stripping process but before the lock has self-released, preferably by manually acting upon the forced locking mechanism. This action can be performed without tools, if necessary.

[0017] In a preferred embodiment, the locking mechanism can act between a control lever and the movable jaw of the jaws. During jaw operation, the control lever is preferably actuated via the movable jaw, but is preferably mounted so that it can pivot relative to the movable jaw. This relative mobility of the control lever to the movable jaw is used to form the locking mechanism.

[0018] In a further embodiment, the forced locking mechanism can provide a ratchet-like interaction between the control lever and the movable jaw of the clamp, which, in addition to the resulting backstop, may also be perceptible as an acoustic signal. Brief description of the drawings

[0019] The invention is explained in more detail below with reference to the accompanying drawing, which, however, only represents an exemplary embodiment. It shows: Fig. 1 shows a hand crimping tool of the type in question in perspective; Fig. 2 shows a detailed perspective view of the position of a cable end to be crimped in relation to a crimping opening of the hand crimping tool; Fig. 3 shows the section along section plane III. Figure 1 , concerning the unloaded basic position of the hand pliers; Fig. 4 one of the Figure 3 corresponding sectional view, but concerning an intermediate position during crimping; Fig. 5 the magnification of area V in Figure 4; Fig. 6 a subsequent representation to the representation in Figure 5 , relating to a position after crimping has been carried out; Fig. 7 one of the Figure 5 corresponding representation, however, in the case of crimping a pellet with the opposite of the one in Figure 5 shown compact with reduced diameter; Fig. 8 another of the Figure 5 corresponding representation, with a further reduced pellet diameter compared to the representation in Figure 7 ; Fig. 9 a subsequent representation to Figure 3 , concerning the use of hand pliers during a wire stripping process; Fig. 10 the enlargement of area X in Figure 9 ; Fig. 11 a subsequent representation to Figure 10 , relating to an intermediate position during the stripping process; Fig. 12 a subsequent representation to Figure 11 , concerning a position after completion of the stripping process. Description of the embodiments

[0020] The presentation and description initially refers to Figure 1, a hand pliers 1 with a pliers head K, comprising two pliers jaws 2, 3, and two pliers arms 4, 5. The pliers jaws 2 and 3 define a pliers mouth M in an end face T of the hand pliers 1.

[0021] The jaw 2 of the pliers, which is referred to below as fixed, is directly and firmly connected to the shank 4 of the pliers via a cheek area 6.

[0022] In the cheek area 6, the wire stripper 1 provides a bearing for a rotary axis 7 with a geometric axis x, about which the jaw 3, which is movable further below, is rotatably mounted.

[0023] The bearing of the movable jaw 3 on the axis of rotation 7 results in the area of ​​a shoulder area of ​​the movable jaw 3 extending in the direction of extension of the axis x in projection to the cheek area 6 of the stationary jaw 3.

[0024] The geometric axis x preferably extends perpendicularly to a broad side B of the pliers head K, to which broad side B essentially perpendicular and narrow sides S run above and below in the usual handling position, the extension length a of which perpendicular to a broad side B may correspond to one third or less, for example down to one tenth or less, of the extension length b of the broad side B considered transversely to the axis x.

[0025] The jaw opening position, for example as shown in Figure 3 , may be limited by a stop.

[0026] The further jaw of the pliers 5 is pivotally mounted about a further geometric axis y, which is aligned parallel to the axis of rotation 7 or its geometric axis x. The corresponding physical axis is likewise held in the cheek area 6 of the stationary jaw 2 or the stationary jaw 4.

[0027] The movable jaw 5 of the pliers is pivotable about the axis y in the direction towards the fixed jaw 4, wherein a pivoting displacement of the movable jaw 5 in the direction towards the fixed jaw 4 causes a coupled pivoting movement of the movable jaw 3 about the axis x.

[0028] For this purpose, a preferably angled control lever 8 is attached to the movable handle part 5, the free end of which, in the illustrated embodiment with a roller 9 preferably arranged in this area, rests against an, for example, cam-like extension 10 of the shoulder area of ​​the movable jaw of the pliers 3.

[0029] The control lever 8 is pivotally mounted on the movable jaw 5 of the clamp. The pivot axis z preferably runs parallel to the geometric axis of rotation x.

[0030] Furthermore, the movable handle part 5 acts via a linkage 11 on a cutting edge 12 which is pivotally mounted in the cheek area 6 of the stationary jaw 2. The cutting edge 12 is mounted in the cheek area 6, with its geometric axis also running parallel to the geometric axis of rotation x of the movable jaw 3.

[0031] The cutting edge 12 lies in a free-cut area 13 of the cheek area 6 in the narrow side S which, in normal handling, preferably points downwards and is preferably used for cutting a cable to length, for example a cable to be stripped in a further step.

[0032] By pivoting the cutting edge 12 during the pivoting displacement of the movable jaw 5 towards the stationary jaw 4, a cable that may be located in the area 13 is cut by the pivoting cutting edge 12, with the cable supported on the flanks of the cheek area 6, which define the area 13.

[0033] Facing the front face T, in particular the jaws M of the pliers, the hand pliers 1 have a stripping device A which is coupled to the movement of the pliers arm 5 and the control lever 8.

[0034] Furthermore, the hand pliers 1 have a crimping device C facing a lower narrow side S in normal handling, in which a cable 14, for example stripped with the stripping device A, can be crimped with a crimping piece 16, in particular in the form of a wire end sleeve, in the area of ​​the conductors 15 exposed thereafter.

[0035] The crimping device C can, preferably, be provided between the area 13 for cutting a cable and the end face T, for which purpose a crimping opening 18 is left in the jaw wall 17 of the stationary pliers jaw 2 forming the narrow side S in question.

[0036] In the fixed pliers jaw 2, a crimping jaw receptacle 19 is formed adjacent to the crimping opening 18, in which a first crimping jaw 20 and a second crimping jaw 21 are jointly received and linearly guided. For example, in Figure 5 The depicted displacement direction r of the crimping jaws 20 and 21 can, as further preferred, be essentially aligned with an alignment and displacement direction of a pull rod 22 pivotably connected to the control lever 8 and cooperating with the stripping device A.

[0037] A spring 23, here a cylindrical compression spring, is preferably arranged between this pull rod 22 and the boom 10, which moves the movable jaw 5 towards the Figure 3 The basic position shown is loaded. In this basic position, the movable jaw 3 can also be held in a stop-limited basic position.

[0038] In the illustrated embodiment, the second crimping jaw 21 is arranged facing the end face T, starting from the crimping opening 18, and can only be displaced indirectly and linearly in the crimping jaw receptacle 19 during a crimping process. The first crimping jaw 20, on the other hand, can be displaced linearly in the crimping jaw receptacle 19 directly by means of a drive plunger 24, which is pivotably mounted on both the first crimping jaw 20 and the link 11 or the cutting edge 12 about axes 25 and 26 preferably aligned parallel to the axes x and / or y and / or z. The drive plunger 24 is designed in a link-like manner.

[0039] The two crimping jaws 20 and 21 are provided with partially comb-like interlocking ribs 27, which, looking in the direction of insertion of the cable 4, fitted with the crimping piece 16, into the crimp opening 18, are approximately triangular in shape. This results in the following in an unloaded initial position according to Figure 3 a crimping jaw 28 with a rectangular, in particular square, plan view (compare for example Figure 2 ).

[0040] Regarding the rib-like design of the crimping jaws 20 and 21 and the resulting design of the crimping mouth 28, reference is made, for example, to DE 10 2018 101 159 A1.

[0041] The second crimping jaw 21, guided in the crimping jaw receptacle 19, is supported by a spring 29 in a base area of ​​the crimping jaw receptacle 19. This spring can, and preferably, be an elastic, resilient polyurethane spring which is compressible when subjected to pressure, building up a restoring spring force.

[0042] The jaws of the pliers 4 and 5 preferably interact via a locking mechanism 30 when actuated. The latter preferably interacts with respect to both the crimping device C and the stripping device A, and optionally also with respect to the cutting device for cutting cables using the cutting edge 12.

[0043] The locking mechanism 30 has a pawl 31 pivotally mounted on the movable jaw 5 of the pliers and a ratchet projection 32 on the control lever 8 that interacts with the pawl 31 during the handling of the hand pliers 1. The pawl 31 is held in a basic position, for example according to, by means of a tension spring 33. Figure 3 charged.

[0044] The pawl 31, which is pivotable about an axis 34 aligned parallel to the axes described above, has a substantially radially projecting pawl finger 35 for ratcheting interaction with several detent stages 36, for example, as shown, three detent stages 36, of the ratchet projection 32.

[0045] In the circumferential direction with respect to the axis 34, an actuating finger 37 can be provided, by means of which the pawl 31 can be manually pivoted into a position releasing the ratchet projection 32.

[0046] Regarding the pivotability of the latch 31, a stop limit may be provided in one and / or the other pivoting direction.

[0047] Due to the locking mechanism 30, during normal handling of the hand pliers 1, it is ensured that the crimping or stripping process, and optionally the cutting process, is completely finished, and that a preferred end position of the respective tool is reached. Before this end position is reached, the interaction of the pawl 31 and the ratchet projection 32 prevents the movable pliers arm 5 from moving back towards the home position, and thus also prevents the movable pliers jaw 3 and / or the crimping jaws 20 and 21 from moving back into their home position. In these intermediate handling positions, the pawl finger 35 engages with one of the detent positions 36 to lock the pliers in place.

[0048] Due to the arrangement of the positive locking device 30, the displacement path of the first crimping jaw 20, connected to the drive plunger 24, is essentially constant, regardless of the thickness d of the crimping piece 16 considered in the displacement direction r of the crimping jaws 20 and 21. The differential path resulting from the thickness d of the crimping piece 16, over which the second crimping jaw 21 must displace linearly with the first crimping jaw 20 in the displacement direction r, is enabled by the arrangement of the spring 29. The corresponding support of the second crimping jaw 21 by the spring 29 allows for a different linear displacement of the second crimping jaw 21 over the differential path, wherein, according to a preferred embodiment, the spring force of the spring 29 is particularly limited in the initial position, which is preferably stop-limited with respect to the second crimping jaw 21. Figure 3The spring force must be sufficiently high to absorb the pressing forces acting on the first crimping jaw 20 during a typical crimping operation. A displacement of the second crimping jaw 21 against the restoring force of the spring 29 can thus only occur once the crimping is complete, or alternatively, concurrently with the crimping process.

[0049] Due to the different possible displacement paths of the second crimping jaw 21 depending on the thickness d of the pressing part 16, different lengths l of the spring 29 result in the crimping end position, whereby this length l decreases with increasing thickness d of the pressing part 16 (compare in particular the Figures 6 to 8 ). Accordingly, with increasing thickness d of the pressing 16, a higher compression of the spring 29 results to compensate for the displacement path forced by the forced locking 30, in particular of the second crimping jaw 21.

[0050] During the crimping process, a center point of the crimping jaw 28 formed between the crimping jaws moves relative to the stationary pliers jaw 2.

[0051] The two jaws of the pliers 2 and 3 each have an outer clamping jaw 38, 39, for clamping a cable 14 inserted into the jaws of the pliers for stripping a free end, see also Figures 9 to 10 .

[0052] Furthermore, two inner cutting jaws 40, 41 are provided with respect to the arrangement of the clamping jaws 38 and 39 relative to the geometric axis of rotation x, each with cutting edges 42, 43 fixed in the end region facing the clamping jaws 38 and 39. The cutting edges 42 and 43 are arranged to point towards each other.

[0053] In the operational arrangement of the cutting jaw pair, the geometric axis of the pivot axis 44 preferably extends in parallel alignment to the axis of rotation x of the movable pliers jaw 3.

[0054] A spring 45 is arranged between the cutting jaws 40 and 41, which spring 45 loads the cutting jaws 40 and 41 into an open position spaced apart from each other.

[0055] In the illustrated embodiment, a stop slide 46, which can be locked in the extension direction of the cutting jaw 41, is provided on the lower cutting jaw 41, i.e. on the cutting jaw 41 associated with the stationary jaw 2, to provide a stop for the free end of the cable 14 inserted into the jaw M of the pliers, in order to define the length of the area to be stripped.

[0056] The cutting jaws 40 and 41 are guided laterally in the respective associated jaw 2, 3 to enable proper sliding displacement of the cutting jaws 40 and 41 in the direction of their longitudinal extension, i.e. starting from an initial position associated with the clamping jaws 38 and 39 in the direction of an end position spaced apart from the clamping jaws 38 and 39 and displaced in the direction of the axis of rotation x and from this end position back to the initial position.

[0057] The pull rod 22 is provided for this repositioning of the cutting jaws 40, 41. The cutting jaws 40, 41 can be moved from a starting position to a final position by squeezing the handle parts 4, 5 against the force of the spring 23 acting on the pull rod 22.

[0058] The pull rod 22 is also guided through the physical axis of rotation 7 by means of a pull rod-side, elongated hole-like recess 47.

[0059] Associated with the pivot axis 44 of the cutting jaw pair, the drawbar 22 has an entry opening 48 that is directed essentially towards the stationary jaw 2 and, furthermore, essentially in the closing and opening directions of the cutting jaws 40 and 41. This opening is created by an overall hook-like design of the corresponding end region of the drawbar 22.

[0060] In this entry opening 48, the pivot axis 44 of the cutting jaw pair lies in the usual operating position of the hand pliers 1, so that a sliding displacement of the pull rod 22 made possible by the elongated design of the recess 47 leads to a corresponding sliding displacement of the cutting jaw pair.

[0061] This sliding displacement of the pull rod 22 is made possible by a coupling with the control lever 8 held on the movable handle part 5, which control lever 8 engages in a pull rod-side bore 49 with a pull axis 55 aligned parallel to the axis of rotation 7, which in the illustrated embodiment can also form the axis for the roller 9.

[0062] Each cutting jaw 40, 41 is supported in the associated pliers jaw 2, 3 via a cam section 50, 51, which cam section 50, 51 in turn can be supported on a clamping jaw fixed cam.

[0063] This indirect support of the cutting jaws 40, 41 on the respective pliers jaws 2, 3 is known, for example, from EP 1 557 920 B1. Reference is also made to the content of this patent specification regarding the mode of operation.

[0064] During the compression of the plier handles 4 and 5, the jaws of the pliers M are initially closed by a corresponding pivoting movement of the movable jaw 3, superimposed on a closing of the cutting jaw pair (compare Figure 9 and 10 The cutting edges 42 and 43 of the cutting jaws 40 and 41 cut into the insulation sheath of the cable 14, with a cutting depth that is preferably adjusted automatically depending on the cable thickness.

[0065] With further pivoting of the movable jaw 5 towards the stationary jaw 4 as shown in the illustration in Figure 11The roller 9 of the boom 10 slides along the facing and previously described end face of the boom 10, overcoming the restoring force of the spring 23 acting on the drawbar 22. The drawbar 22 is pulled linearly in a direction away from the jaws M, dragging the pair of cutting jaws along with it. This causes the insulation section 54, separated by the cutting edges 42 and 43, to be stripped from the cable 14.

[0066] Upon further compression of the plier arms 4 and 5, the roller 9 on the cantilever side leaves its supporting position relative to the cantilever 10 of the movable plier jaw 3, which pivots back towards its open-home position, simultaneously opening the plier mouth M and the pair of cutting jaws. This is due, among other things, to the restoring force of the spring 45 located between the cutting jaws 40 and 41.

[0067] The cable 14, with its end stripped, is freely accessible for removal from the hand pliers 1. The severed and removed insulation section 54 is freely accessible for removal or, if necessary, falls automatically from the jaws of the pliers M.

[0068] The stripped end of the cable, which may be fitted with a ferrule, for example, can then be crimped or pressed using the same hand pliers 1. List of reference symbols 1 Hand pliers 30 Compulsory closure 2 Pliers jaw 31 pawl 3 Pliers jaw 32 Ratchet advantage 4 Pliers handles 33 tension spring 5 Pliers handles 34 axis 6 cheek area 35 Doorknob finger 7 axis of rotation 36 Detent position 8 control lever 37 Actuating finger 9 role 38 Clamping jaw 10 boom 39 Clamping jaw 11 handlebars 40 Cutting jaw 12 Cut 41 Cutting jaw 13 Area 42 Cut 14 Cable 43 Cut 15 vein 44 Swivel axis 16 Pressing 45 Feather 17 cheek wall 46 Stop slide 18 Crimp opening 47 Exclusion 19 Crimp jaw holder 48 Entrance opening 20 first crimping jaw 49 Drilling 21 second crimping jaw 50 Scenery piece 22 pull rod 51 Scenery piece 23 Feather 52 handlebars 24 Drive tappet 53 handlebars 25 axis 54 Isolation section 26 axis 55 traction axis 27 rib 28 crimp jaw a length 29 Feather b length d thickness l length r Direction of displacement A wire stripper B broadside C Crimping device K Pliers head M Pincer jaw S narrow side T front side

Claims

1. Hand pliers (1), designed to carry out crimping, having one stationary and one movable plier leg (4, 5) and a first and a second crimping jaw (20, 21), wherein the first crimping jaw (20) is acted on by a drive tappet (24), characterized in that the first and the second crimping jaw (20, 21) are provided with ribs (27) which engage in one another in a partially comb-like manner and which are preferably approximately triangular in shape when viewed in the direction of an insertion direction of a cable (4) provided with the pressed part (16) into the crimping opening (18), wherein in an unloaded basic position, this results in a crimping mouth (28) that is rectangular in plan view, in that the second crimping jaw (21) can be moved back inside a crimping jaw receptacle (19) of the hand pliers (1) against spring force, and in that the first and the second crimping jaw (20,21) are arranged in a common linear guide.

2. The hand pliers (1) according to claim 1, characterized by a plier head which is formed by mutually pivotable plier jaws (2, 3) which interact for stripping, wherein the plier head has a broad side (B), a first and a second narrow side (S) extending in a usual handling position on the upper and lower sides substantially at right angles to the broad side, and an end face (T), wherein further a pivot axis (x) of the plier jaws (2, 3) extends at right angles to an extent of the broad side (B), and a crimping opening (18) formed by the crimping jaws (20, 21) opens into the first or second narrow side (S).

3. The hand pliers according to claim 1, characterized in that the hand pliers (1) are further designed as stripping pliers.

4. The hand pliers according to any one of the preceding claims, characterized in that the plier legs (4, 5) interact via a positive lock (30).

5. The hand pliers according to claim 4, characterized in that the positive lock (30) acts between a control lever (8) and the movable plier leg (5).