Tool head for one tool

Description

field of technology

[0001] The invention relates to a tool head for a tool according to claim 1 or 3, in particular for a hydraulically actuated tool, wherein the tool head, in a side view, has a substantially C-shaped head body with two C-legs opposite one another along a longitudinal axis of the tool head and a connecting web connecting the C-legs, wherein a first C-leg has a first tool carrier for receiving a first tool part, and wherein a second C-leg has a second tool carrier for receiving a second tool part, wherein the second tool carrier is mounted in the tool head so as to be displaceable towards the first tool carrier, so that the second tool carrier can be displaced from an initial position remote from the first tool carrier by passing through a tool mouth of the C-shaped head body into an end working position adjacent to the first tool carrier,and wherein the connecting web has, in a side view transverse to the longitudinal axis of the tool head, a plurality of through-openings arranged one behind the other along the longitudinal axis, wherein adjacent through-openings are separated by a material strut and the head body of the tool head is manufactured by a metal casting process.

[0002] Furthermore, the invention relates to a method for producing such a tool head. State of the art

[0003] Tool heads of the aforementioned type are known in various designs in the prior art. The tool heads, in conjunction with corresponding tool parts, are used, for example, for pressing, cutting, or punching workpieces. For example, such a tool with a tool head is described in EP 1 084 798 B1, also published as US Pat. No. 6,718,870 B1.

[0004] A tool head according to the preamble of claims 1 and 3 is further disclosed in US 6 619 101 B1.

[0005] Furthermore, it is known to construct the tool head essentially as a single piece and from the same material. The tool head can then be connected to a hydraulic unit, preferably through a cylindrical configuration along its longitudinal axis, directly or indirectly via an adapter. The tool can be designed as an exclusively hand-supported tool with a rod-shaped tool body base, so that one-handed operation of the tool is generally possible, or alternatively as a tool with a separately provided hydraulic unit connected to the tool head via a hydraulic hose. Summary of the invention

[0006] Based on the aforementioned prior art, the object of the present invention is to further develop a tool head of the aforementioned type, both with regard to the lowest possible weight and with regard to operational reliability. In particular, the aim is to prevent parts of the head body from becoming detached in the event of a breakage of the head body due to the end of the tool head's service life, which could otherwise cause serious injuries to users of the tool.

[0007] The problem is solved first of all in the subject matter of claim 1, wherein the through-openings follow an arcuate configuration of the connecting web and are not formed on a line parallel to the longitudinal axis of the tool head.

[0008] This object is further achieved in the subject matter of claim 2, wherein a through opening is formed in a linear extension of the device mouth relative to the longitudinal axis.

[0009] This object is further achieved in the subject matter of claim 3, wherein it is based on the fact that an edge region of the connecting web spaced from the device mouth by the through openings has an edge height transverse to the longitudinal axis which is 20 percent to 40 percent of an opening height of a through opening and that the material strut has a strut width, based on a viewing direction transverse to the opening plane of the through opening, which corresponds to approximately 10 percent to 50 percent of an opening width of the through opening.

[0010] Accordingly, the head body can be made of steel or titanium. The tool head manufactured using a metal casting process has the consistency of conventionally forged steel, but can be manufactured more cost-effectively. In particular, manufacturing using an investment casting process using heat-treated steel can achieve a tool head that is preferably void-free or at least has a reduced number of voids. Alternatively, the tool head can also be made of an alloy based predominantly on titanium, which can achieve further weight savings.

[0011] The connecting web of the tool head has, as viewed from the side, several through-openings arranged one behind the other along the longitudinal axis, transverse to the longitudinal axis of the tool head. These through-openings serve to vent cracks in the connecting web, for example, cracks caused by age, which could otherwise penetrate the connecting web completely to an edge area facing away from the tool mouth of the head body and thus cause parts of the tool head to be thrown off or at least fall off. The aforementioned through-openings can, on the one hand, achieve a significant weight saving for the tool head, and, on the other hand, advantageously complement the design of the tool head from cast metal, since this can then compensate for any instabilities caused by shrinkage cavities in the cast material.The through-holes incorporated into the connecting web thus achieve a topology improvement, making it possible to reduce the tool head to a basic structure that ensures the required stability under the load or forces typically to be withstood. In exemplary embodiments, such tool heads are suitable in practice for forces of more than 100 kN, for example 120 kN or even more. Depending on the reduction in material volume through the through-holes, which represent material recesses within the connecting web, significant weight savings can be achieved. The previously described structure of the connecting web with the through-holes can also ensure advantageous fracture behavior. The material savings achieved through the through-holes are limited by the required thickness and strength of the tool head.

[0012] In conjunction with the formation of the tool head body using a metal casting process, a geometry can be achieved that cannot be achieved using conventional manufacturing methods such as forging. The through holes are incorporated into the tool head, specifically into its connecting web, in such a way that the essential support structures of the original geometry are retained without through holes. In practice, the weight savings achieved through the through holes can amount to 25 percent or more of the original tool head.

[0013] In particular, to ensure the safety function achieved by the through-openings, it is recommended that at least one of the through-openings be formed directly parallel to the tool mouth of the head body, namely, in relation to the longitudinal axis of the tool head, in a section of the connecting web arranged parallel to the tool mouth. A crack originating from the tool mouth of the tool head therefore ends, due to the design, in a through-opening and not at an outer edge area of ​​the connecting web. A section of the connecting web further away from the tool mouth can thus remain undamaged if a crack occurs due to the end of the tool head's service life. This effectively prevents parts of the tool head from breaking off and being thrown away or falling down.

[0014] Furthermore, it can be provided that an edge region of the connecting web, spaced from the tool mouth by the through-openings, has an edge height transverse to the longitudinal axis that amounts to 20 percent to 40 percent of the opening height of a through-opening. The material thickness of the edge region remaining at the outer edge of the connecting web next to the through-openings is thus significantly less than the opening height of the adjacent through-opening. However, the ratio between the height of the material recess of the through-opening and the edge region of the connecting web remaining adjacent to it is in any case dimensioned such that the required stability with respect to the tool head is maintained.

[0015] It is proposed that the connecting web have three to five, in particular four, through-openings which, as viewed in the side view, are arranged next to one another in an arc from the first C-leg to the second C-leg, transverse to the longitudinal axis of the tool head. The juxtaposition of the through-openings can thus essentially follow the C-shape of the tool head. Starting from a geometric center of the tool mouth, as viewed in a side view of the C-shape of the head body, this can result in a star-shaped arrangement of the through-openings around the geometric center, wherein the through-openings extend radially from the tool mouth in the direction of the edge region of the connecting web facing away from the tool mouth, but do not sever any residual material of the edge region.Due to the curved arrangement of the through-openings around a circumferential section of the device mouth, cracks originating from any point of the device mouth can be successfully intercepted so that they cannot completely sever the connecting web, but end in a through-opening adjacent to the device mouth.

[0016] Two or more of the material struts may be formed so as to diverge from one another with respect to their respective longitudinal center axes, with a large distance from one another in regions of the material struts remote from the device mouth.

[0017] Furthermore, it is proposed that one, several or all of the through openings widen from the tool mouth of the head body to an edge region of the connecting web facing away from the tool mouth of the head body. In relation to a radial direction starting from a center of the tool mouth, the through opening thus widens so that the material recess is formed to a relatively greater extent towards the outer edge region of the connecting web, so that the tool mouth of the head body is surrounded by a relatively large amount of material and thus the stability of the head body is not reduced. At the same time, the material recesses of the through openings reduce the weight of the tool head. The widening is achieved in particular by a mutually diverging alignment of two, three or all of the material webs.

[0018] Furthermore, with regard to the design of the material struts, it is proposed that the material strut have a strut width, viewed transversely to the opening plane of the through-opening, that corresponds approximately to 10 percent to 50 percent of the opening width of the through-opening. The material struts formed between the through-openings are thus significantly thinner than the width of the through-opening. As a result, the probability that a crack originating from the tool mouth of the head body will terminate in a through-opening is significantly higher than the probability that the crack will reach a material strut and there sever the entire connecting web in a radial direction, resulting in the detachment of parts of the tool head.

[0019] In this context, it is particularly proposed that one, several, or all material struts have a substantially constant strut width, extending from the device mouth of the head body to an edge region of the connecting web facing away from the device mouth of the head body. The material struts are thus preferably no wider adjacent to the device mouth than at the outwardly facing edge region of the connecting web, so that the previously described transition region between the device mouth and the material strut is as narrow as possible and the probability of damage from a crack is particularly low. According to a special embodiment, it can also be provided that the material struts widen starting from the device mouth, so that their stability is increased in the outer edge region of the connecting web.

[0020] Alternatively, it can be provided that the material strut is essentially waist-shaped with respect to a viewing direction transverse to the opening plane of the through-opening, wherein the material strut initially tapers from the tool mouth of the head body to an edge region of the connecting web facing away from the tool mouth of the head body and then widens again. In this embodiment, the material struts can be tapered in a central region with respect to their longitudinal extent in order to further reduce the weight of the tool head. Furthermore, the relatively wider design at the transition regions to the tool mouth and the edge region of the connecting web remote from the tool mouth allows a stable basic shape of the tool head to be maintained.

[0021] It can also be provided that, based on a direction parallel to the longitudinal axis of the tool head, a through opening has an opening width which corresponds approximately to 50 percent to 100 percent of a width of the tool mouth of the head body. According to this embodiment, in particular one of several through openings can have a particularly large opening width, so that the through opening runs along a large part of the longitudinal extent of the tool mouth and cracks emanating from the tool mouth therefore end in the through opening and do not run to a material strut. One of several through openings can thus be designed to be significantly larger, i.e. wider, relative to the other through openings, for example have an opening width twice as large.Depending on the design of the tool head and the particular load on the material in certain parts of the tool mouth, a more or less wide through-opening can be provided.

[0022] Finally, in addition to the tool head described above, a method for producing such a tool head is also proposed. The method involves producing the head body of the tool head by metal casting. In particular, it is proposed that the head body be produced by investment casting of steel or titanium. Investment casting can be a lost-wax casting. The model, which is first manufactured for this purpose and then encased in a molding compound, can be made of another meltable material, such as plastic, as an alternative to wax. Short description of the drawings

[0023] The invention is explained below with reference to the accompanying drawings, which, however, represent only exemplary embodiments. A component of the illustrated tool head, which is explained only with reference to one of the exemplary embodiments, but could also be used in another embodiment according to the invention, is thus also described as being possible for the other embodiment. The drawings show in detail: Fig. 1 shows a tool with a tool head according to the invention in a first embodiment, Fig. 2 shows a side view of the tool, Fig. 3 shows a longitudinal section of the tool head, Fig. 4 shows a top view of the tool according to Figure 1 , Fig. 5 a tool with a tool head according to the invention according to a second embodiment, Fig. 6 a side view of the tool, Fig. 7 a longitudinal section of the tool head, Fig. 8 a top view of the tool according to Figure 2 . Description of the embodiments

[0024] The figures described below show two different possible embodiments of a tool 2, wherein the Figures 1 to 4 relate to a first embodiment, and wherein the Figures 5 to 8 a second possible embodiment. In addition, other alternative designs are also possible, so that the Figures 1 to 8 are not to be understood as limiting here, but rather serve to explain the possible features.

[0025] Figure 1shows a tool 2 with a rod-shaped body tool base 20, on the free end piece 21 of which an accumulator 22 for supplying energy to the tool 2 is arranged. The tool 2 is, for example, a hydraulically actuated crimping tool 2. Alternatively, the tool 2 can also be modified so that it serves other purposes, for example cutting or punching workpieces. The body tool base 20 further has a handle 23 by which a user can guide the tool 2. In addition to the handle 23 of the body tool base 20, the tool 2 can, for example, have a further handle part (not shown here) in order to be able to guide and hold particularly heavy tools 2 safely, in particular when one-handed operation is not possible due to the weight.In particular, within the scope of the invention, tools 2 can also be designed that have a separately provided unit, in particular a separate power supply device, a separately provided hydraulic unit connected to a tool head 1 of the tool 2 via a hydraulic hose, or the like. In the embodiment provided according to the figures shown here, the tool head 1 of the tool 2 is connected via an adapter 24 to a hydraulic unit that is integrated into a tool body 25 of the tool 2.

[0026] The tool head 1 of the tool 2 has an integrally formed head body 3. The head body 3 can be seen with reference to a side view according to Figure 2 or Figure 3, in which a longitudinal axis x of the tool 2 or tool head 1 is represented as a line, can be designed approximately C-shaped overall. The head body 3 has a first C-leg 4 and a second C-leg 5, which are connected by a connecting web 6 that is designed essentially parallel to the longitudinal axis x. The two C-legs 4, 5 and the connecting web 6 span a device mouth 11, into which a workpiece to be machined by means of the tool 2 can be inserted. The first C-leg 4 has a first tool carrier 7. The second C-leg 5 has a second tool carrier 8. The first tool carrier 7 is designed integrally in one piece with the first C-leg 4, while the second tool carrier 8 can be displaced into the device mouth 11 relative to the first tool carrier 7.The second tool carrier 8 is here, for example, hydraulically displaceable by a hydraulic piston 26 linearly displaced in the tool body 25.

[0027] Each of the two tool carriers 7, 8 serves to preferably releasably receive a tool part 9, 10, wherein the first tool carrier 7 carries a first tool part 9, and wherein the second tool carrier 8 carries a second tool part 10. For the releasable fastening of the tool part 9, 10 to the associated tool carrier 7, 8, the tool part 9, 10 and the tool carrier 7, 8 have corresponding holding means 27, 28. The respective tool part 9, 10 can, for example, be locked to the corresponding tool carrier 7, 8. Furthermore, the second tool carrier 8, which is mounted in the body tool 25 for linear sliding movement, can preferably be removed from the head body 3 of the tool head 1 via the device mouth 11.

[0028] The tool head 1 has a plurality of through-openings 12, 13, 14, 15 on the connecting web 6, which are separated from each other by material struts 17, 18, 19. An opening plane of the through-openings 12, 13, 14, 15 is parallel to a plane in which the head body 3 is located, as for example in the Figures 2 and 3 recognizable, C-shaped. In addition to the through holes 12, 13, 14, 15, a narrow edge area 16 remains on the outside of the connecting web 6, which ensures the stability of the tool head 1. As described in more detail in Figure 3As can be seen, the edge region 16 has an edge height r, which corresponds approximately to 25 percent of an opening height h of the through-opening 12, 13, 14, 15. The material struts 17, 18, 19 existing between the through-openings 12, 13, 14, 15 have a slightly tapered shape, with the respective material strut 17, 18, 19 extending from the device mouth 11 to the edge region 16 of the connecting web 6. An average strut width d in the region of the narrowest point of the waisted course of the material strut 17, 18, 19 is approximately 20 percent of an opening width b of an adjacent through-opening 12, 13, 14, 15. Of the total of four through-openings 12, 13, 14, 15, the through-opening 13 is clearly particularly large and has an opening width b and opening height h which are significantly larger than the opening widths b and opening heights h of the other through-openings 12, 14, 15.The through-opening 13 extends, relative to a direction parallel to the longitudinal axis x, almost along the entire width z of the tool mouth 11. As a result, cracks originating from the tool mouth 11, which may be caused, for example, by the tool head 1 reaching the end of its service life, can be reliably absorbed by the through-opening 13 and thus do not reach the edge region 16 of the connecting web 6. The material struts 17, 18, 19 are arranged depending on the geometry of the head body 3 such that cracks originating at the edge of the tool mouth 11 do not usually run to a material strut 17, 18, 19, but rather to a through-opening 12, 13, 14, 15.The size of the through-openings 12, 13, 14, 15 with their specific opening width b and opening height h thus saves weight on the tool head 1 and, on the other hand, interrupts crack growth as soon as a crack arrives in a through-opening 12, 13, 14, 15. In conjunction with the inventive production of the tool head 1 from cast metal, fractures or cracks resulting from any casting defects, such as shrinkage cavities, are thus also non-critical. The tool head 1 is manufactured here, for example, from steel or titanium using an investment casting process.

[0029] The through-openings 12, 13, 14, 15 follow the overall curved configuration of the connecting web 6 and are therefore not formed on a line parallel to the longitudinal axis x of the tool head. This allows a distance between a through-opening 12, 13, 14, 15 and the tool mouth 11 to be essentially maintained, so that the probability of unwanted crack propagation along the circumference of the tool mouth 11 is essentially equally low.

[0030] The Figures 5 to 8 show an alternative embodiment of a tool head 1 according to the invention. This tool head 1 also has four through-openings 12, 13, 14, 15, which, however, compared to the through-openings 12, 13, 14, 15 according to the Figures 1 to 4- are smaller and have similar opening widths b and opening heights h. This makes the tool head 1 more stable overall and can absorb larger loads compared to the tool head 1 of the first embodiment. Furthermore, the material struts 17, 18, 19, as shown particularly in the Figures 6 and 7 visible, a substantially constant strut width d along its longitudinal extent. Furthermore, the through openings 12, 13, 14, 15 also follow according to the embodiment of the Figures 5 to 8 an arc shape along the circumference of the substantially C-shaped head body 3. List of reference symbols 1 tool head b Opening width 2 Tool d Strut width 3 head body h Opening height 4 C-leg r Edge height 5 C-leg x Longitudinal axis 6 connecting bridge z Width 7 tool carrier 8 tool carrier 9 tool part 10 tool part 11 Device mouth 12 passage opening 13 passage opening 14 passage opening 15 passage opening 16 peripheral area 17 Material strut 18 Material strut 19 Material strut 20 Hull tool base 21 End piece 22 accumulator 23 Handle 24 adapter 25 Hull tool body 26 hydraulic piston 27 Holding devices 28 Holding devices

Claims

1. A tool head (1) for a hydraulically actuatable tool (2), wherein the tool head (1), as viewed from the side, has an essentially C-shaped head body (3) with two C-legs (4, 5) lying opposite each other along a longitudinal axis (x) of the tool head (1) and a connecting web (6) that connects the C-legs (4, 5), wherein a first C-leg (4) has a first tool carrier (7) for receiving a first tool part (9), and wherein a second C-leg (5) has a second tool carrier (8) for receiving a second tool part (10), wherein the second tool carrier (8) is mounted in the tool head (1) so as to be displaceable to the first tool carrier (7), so that the second tool carrier (8) can be displaced from a first starting position remote from the first tool carrier (7) while traversing a device jaw (11) of the C-shaped head body (3) into a final working position adjacent to the first tool carrier (7), and wherein the connecting web (6), as viewed from the side transverse to the longitudinal axis (x) of the tool head (1), has several through openings (12, 13, 14, 15) lying one behind the other along the longitudinal axis (x), wherein adjacent through openings (12, 13, 14, 15) are separated by a material bracing (17, 18, 19), and the head body (3) of the tool head (1) is manufactured in a metal casting process, characterized in that the through openings (12, 13, 14, 15) follow an arched shape of the connecting web (6), and not a line parallel to the longitudinal axis (x) of the tool head (1).

2. A tool head (1) according to claim 1, characterized in that the through openings (12, 13, 14, 15) follow an arched shape of the connecting web (6), and not a line parallel to the longitudinal axis (x) of the tool head (1), and that a through opening (15) is designed as a linear extension of the device jaw (11) in relation to the longitudinal axis (x).

3. A tool head (1) for a hydraulically actuatable tool (2), wherein the tool head (1), as viewed from the side, has an essentially C-shaped head body (3) with two C-legs (4, 5) lying opposite each other along a longitudinal axis (x) of the tool head (1) and a connecting web (6) that connects the C-legs (4, 5), wherein a first C-leg (4) has a first tool carrier (7) for receiving a first tool part (9), and wherein a second C-leg (5) has a second tool carrier (8) for receiving a second tool part (10), wherein the second tool carrier (8) is mounted in the tool head (1) so as to be displaceable to the first tool carrier (7), so that the second tool carrier (8) can be displaced from a first starting position remote from the first tool carrier (7) while traversing a device jaw (11) of the C-shaped head body (3) into a final working position adjacent to the first tool carrier (7), and wherein the connecting web (6), as viewed from the side transverse to the longitudinal axis (x) of the tool head (1), has several through openings (12, 13, 14, 15) lying one behind the other along the longitudinal axis (x), wherein adjacent through openings (12, 13, 14, 15) are separated by a material bracing (17, 18, 19), and the head body (3) of the tool head (1) is manufactured in a metal casting process, characterized in that an edge area (16) of the connecting web (6) spaced apart from the device jaw (11) by the through openings (12, 13, 14, 15) has an edge height (r) transverse to the longitudinal axis (x) that measures 20 percent to 40 percent of an opening height (h) of a through opening (12, 13, 14, 15), and that the material bracing (17, 18, 19) has a bracing width (d) as viewed transverse to the opening plane of the through opening (12, 13, 14, 15) that corresponds to approximately 10 percent to 50 percent of an opening width (b) of the through opening (12, 13, 14, 15).

4. The tool head (1) according to claim 1 or 2, characterized in that an edge area (16) of the connecting web (6) spaced apart from the device jaw (11) by the through openings (12, 13, 14, 15) has an edge height (r) transverse to the longitudinal axis (x) that measures 20 percent to 40 percent of an opening height (h) of a through opening (12, 13, 14, 15).

5. The tool head (1) according to one of the preceding claims, characterized in that the connecting web (6) has three to five, in particular four, through openings (12, 13, 14, 15), which, as viewed from the side transverse to the longitudinal axis (x) of the tool head (1), are arranged arched one next to the other from the first C-leg (4) up to the second C-leg (5).

6. The tool head (1) according to one of the preceding claims, characterized in that the through opening (12, 13, 14, 15) expands proceeding from the device jaw (11) of the head body (3) up to an edge area (16) of the connecting web (6) facing away from the device jaw (11) of the head body (3).

7. The tool head (1) according to one claims 1 or 2, or 4 to 6, provided the latter do not refer back to claim 3, characterized in that the material bracing (17, 18, 19) has a bracing width (d) as viewed transverse to the opening plane of the through opening (12, 13, 14, 15) that corresponds to approx. 10 percent to 50 percent of an opening width (b) of the through opening (12, 13, 14, 15).

8. The tool head (1) according to one of the preceding claims, characterized in that the material bracing (17, 18, 19) has an essentially constant bracing width (d) proceeding from the device jaw (11) of the head body (3) up to an edge area (16) of the connecting web (6) facing away from the device jaw (11) of the head body (3).

9. The tool head (1) according to one of claims 1 to 7, characterized in that the material bracing (17, 18, 19) is essentially waist-shaped as viewed transverse to the opening plane of the through opening (12, 13, 14, 15), wherein the material bracing (17, 18, 19) initially tapers proceeding from the device jaw (11) of the head body (3) up to an edge area (16) of the connecting web (6) facing away from the device jaw (11) of the head body (3), and then expands again.

10. The tool head (1) according to one of the preceding claims, characterized in that a through opening (12, 13, 14, 15) has an opening width (b) relative to a direction parallel to the longitudinal axis (x) of the tool head (1) corresponding to approx. 50 percent to 100 percent of a width (z) of the device jaw (11) of the head body (3).

11. A method for manufacturing a tool head (1) designed according to one of claims 1 to 10, characterized in that the head body (3) of the tool head (1) is manufactured via investment casting of steel or titanium.