The present application relates to a line guide system for receiving and guiding supply lines between a first body and a second body which can be rotated with respect to each other about a common rotational axis across a rotational angle area. Furthermore, the present application relates to a machine tool having such line guide system.
In machines having two bodies that can be rotated against each other or turned toward each other, such as, for example, in machine tools, it is often necessary to guide supply lines from the first body to the second body by using a line guide system. If, for example, working equipment (e.g., a motor spindle) is attached to the second body, supply lines transporting electric signals and/or fluids to and away from the working equipment usually have to be guided from the first body to the second body. As the supply lines also rotate when the first and second bodies rotate with respect to each other and as a rule are firmly connected to the first and the second body, the first and the second body can be rotated against each other only within a defined rotational angle area. In order to be able to operate the working equipment as flexibly as possible, the rotational angle area should be as large as possible. Furthermore, the line guide system should be able to receive a number of supply lines as large as possible and be designed to be compact. Line guide systems using slip rings and fluid rotary feedthroughs fulfill these requirements; however, they are usually very expensive to produce because they are highly complex components.
Disclosed herein is a line guide system for use in machines of any kind, in particular for use in machine tools, which can be produced at low cost and is compact with regard to its dimensions and is able to receive and guide a multitude of supply lines.
According to at least one embodiment, a line guide system is provided for receiving and guiding supply lines between a first body and a second body which can be rotated with respect to each other about a common rotational axis across a rotational angle area such that the line guide system can be moved from a first rotation condition into a second rotation condition. The line guide system has a plurality of movable guiding lines for respectively receiving supply lines, wherein respective first ends of the guiding lines are disposed in a first fixation portion and respective second ends of the guiding lines are disposed in a second fixation portion. The first fixation portion and the second fixation portion are axially spaced apart from each other with respect to the common rotational axis. The guiding lines are adapted to form a first coil-like segment and a second coil-like segment in the first rotation condition of the line guide system, which each extend at least in part around the rotational axis and are connected with each other via an arc-shaped connecting segment. The first coil-like segment extends along the first coiling direction, and the second coil-like segment extends along a second coiling direction opposite to the first coiling direction. The guiding lines are adapted such that when the line guide system is moved into the second rotation condition, the respective arc-shaped connecting elements unravel such that the guiding lines each have a coil-like extension on the whole along the first coiling direction.
According to the present disclosure, the term “coil-like segment” includes in particular a segment of any length of an (imaginary) coil-like extension. Coil-like in the sense of the present disclosure does not necessarily include a constant pitch, but merely a constant coiling direction.
In other words, a plurality of guiding lines extending adjacently and offset with respect to one other are disposed around the rotational axis, which each have a coil-like extension on the whole (second rotation condition) or a coil-like extension in fact (first rotation condition). Thus, the respective coil-like extensions are “nested” into one another along a peripheral direction around the rotational axis. Preferably, the guiding lines are uniformly spaced apart from the rotational axis respectively across the entire extension along the rotational axis, independent of the respective rotation condition. That is, the guiding lines remain spaced apart with respect to the rotational axis at a constant distance when the line guide system is moved from the first rotation condition into the second rotation condition, and vice versa. Alternatively, corresponding parts of the guiding lines may be uniformly spaced apart from the rotational axis but the individual parts of the same may each be spaced apart from the rotational axis at varying distances.
Due to the fact that a plurality of guiding lines is used, a high number of supply lines can be guided between the first body and the second body. Due to the fact that all guiding lines unravel or create the respective arc-shaped connecting segments (preferably, but not necessarily in a synchronous manner) when the line guide system is moved from the first rotation condition, the guiding lines do not interfere with one another. Furthermore, this makes it possible to maximize the lengths of the guiding lines with respect to a particular portion of the axis (due to the forming of the arc-shaped connecting elements, an additional portion of guiding lines can be accommodated on a circumferential surface around the rotational axis whereby the length of the guiding lines can be increased). This in turn makes it possible to maximize the rotational angle area across which the first body and the second body can be rotated with respect to each other. In addition, the line length required for a particular rotational angle is minimized. Here, the arc-shaped connecting elements are formed in a defined reproducible manner and unravel in a defined reproducible manner. That is, a rotational angle area of the mutual turning of the first and second bodies toward each other within which the arc-shaped connecting segments form and unravel, respectively, and the shape of the formed arcs remain constant (or change only marginally due to an occurrence of wear), independent of how often a change has already been made back and forth between the first rotation condition and the second rotation condition. This means in particular that the arc-shaped connecting elements are not formed because of changing random influences in varying rotational angle areas and in varying shapes. In this connection, the “unraveling” of an arc-shaped connecting segment does not necessarily mean that the course of the winding within a guiding line has the same pitch everywhere but may also mean that a curvature of the arc-shaped partial piece is so small that it is not the coiling direction of the guiding line which is changed within the arc-shaped connecting segment, but merely the pitch of the winding of the guiding line.
According to an embodiment disclosed herein, the rotational angle area is at least 370°. In this case, e.g., the first body and the second body, starting from an initial position, can be rotated against each other in a positive and a negative rotational direction into a −185° position or a +185° position. In this manner, a swiveling range of 360° is completely covered and in each rotational end position)(+180°/−180° a “travel path” of 5° of an additional swiveling area is ensured.
According to an embodiment disclosed herein, in case of a maximum rotational angle area of 370°, the transition point where the arc-shaped connecting element unravels is in an angle area of 100° to 150°, in particular in an area of 115° to 135°, which allows minimization of the required guiding line length when the axial length and the rotational angle are predetermined, whereby the number of guiding lines winding along a portion of the axis may in turn be maximized.
Preferably, the guiding lines are guiding chains or tubes that can be moved/bent/twisted in three spatial directions. This makes it possible to guide the guiding lines like coils free from distortion about the rotational axis.
If the guiding lines are designed as guiding chains, the chain links are designed according to at least one embodiment such that a minimum bending radius of the guiding chains cannot fall short in all three directions in order to protect the supply lines against too strong bending.
Due to the forming or unraveling of the arc-shaped connecting elements (transition points), it is possible that, when the first and second bodies are rotated with respect to each other, corresponding coil diameters formed by the first coil-like segments and the second coil-like segments each remain constant. This in turn makes it possible to keep the line guide system compact because the coil-like segments do not radially expand in case of mutual rotation.
According to an embodiment disclosed herein, a plurality of guiding elements is provided which are each connected to the first body and extend like coils along the first coiling direction. The guiding elements are designed and in an operative connection with the guiding lines (i.e., they guide the latter) such that end portions of the guiding lines facing the first ends have a coil-like extension both in the first rotation condition and in the second rotation condition along the first coiling direction. Thus, the guiding elements ensure that, independent of the current rotation condition, at least a part of each guiding line has a coil-like extension along the first coiling direction. This also makes it possible to ensure that the sites where the arc-shaped connecting segments connect are not formed in an arbitrary manner, but in a defined manner and only within a limited area along the rotational axis.
The guiding elements may, e.g., be disposed such that in the first rotation condition, each guiding line is supported on a respective one of the guiding elements and when the guiding elements are moved into the second rotation condition, the guiding lines are lifted off the guiding elements. In this embodiment, the guiding elements ensure that the guiding lines cannot rest upon one another which could lead to mutual interference (e.g., getting caught). Furthermore, in the case of guiding lines having a high weight, squeezing events are prevented from occurring by one or more further guiding lines resting on one guiding line.
The first body may have a first hollow body formed around the rotational axis, wherein one of the guiding lines may extend on an outer surface of the first hollow body.
Furthermore, the first body may have a second hollow body formed around the first hollow body. At least one of the guiding lines may extend on an outer surface of the second hollow body. Thus, the guiding lines can be apportioned to two different coil radii so that the number of the guiding lines can be increased.
At least one of the guiding lines can extend inside a first cavity formed between the first hollow body and the second hollow body. The forming of such cavity ensures an additional guidance of the guiding lines. In particular, it is possible in this manner that the radius of the coil-like segments extending inside the first cavity neither increases nor decreases when the first and second bodies are rotated with respect to each other.
Furthermore, the first body may have a third hollow body formed around the second hollow body, and at least one of the guiding lines extending inside a second cavity formed between the second hollow body and the third hollow body. Thus, the guiding lines may be apportioned to two different cavities having different coil radii so that the number of the guiding lines can be increased.
The first and second hollow bodies may each be designed to be longer than the third hollow body. This is an advantage when, for example, guiding lines extend inside the second hollow body whose length has to be shorter than the length of the guiding lines extending inside the first cavity.
According to an embodiment disclosed herein, the second body may have a first part arranged so as to be rotatable about the first hollow body inside of or at one end of the first cavity and to which a second end of at least one guiding line is fixed. Furthermore, the second body may have a second part arranged so as to be rotatable about the second hollow body inside of or at one end of the second cavity and to which a second end of at least one guiding line is fixed. Working equipment, for example, a motor spindle, may be firmly connected to the second body. Both the first part and the second part of the second body may be firmly connected to each other.
According to an embodiment disclosed herein, the guiding lines extending through the first hollow body receive lines transporting media, and the guiding lines extending through the second hollow body receive lines transporting electric signals. This makes sense particularly in a case in which the guiding lines guiding electric lines receive a maximum number of supply lines. In this case, guiding lines guiding electric lines usually are less easy to twist than guiding lines guiding fluid lines, and thus it is easier to twist the guiding lines guiding electric lines around a hollow body that has an increased diameter.
The guiding lines extending through the first hollow body may run parallel both in the first and the second rotation condition, and the guiding lines extending through the second hollow body may run parallel both in the first and the second rotation condition. Thus, it is possible to guide the guiding lines in a maximally complication-free manner because they do not interfere with one another.
In all embodiments the guiding lines may be spaced apart uniformly from one another in order to ensure complication-free guiding of the guiding lines.
The second body may have a guiding element disposed between the second ends and the first ends of the guiding lines, the guiding element being designed such that by rotating the guiding element, the respective sites of the guiding lines where the first coil-like segments merge into the second coil-like segments are changed. As mentioned before, the controlled guidance of the guiding lines is thus ensured.
For example, the guiding element may be a guiding ring that is arranged such that each guiding line extends through a respective one of a plurality of openings formed in the guiding ring. The guiding ring may be disposed, e.g., inside the second cavity and extend concentrically around the rotational axis or the first hollow body. This makes it possible to support a part of the guiding lines by the guiding ring which eases the load of the guiding lines in case of a maximum filling of the guiding lines with supply lines and the high weight of the guiding lines resulting therefrom.
The guiding ring may be connected to the second body (e.g., to the second part of the second body) such that when the line guide system is moved into the second rotation condition, the guiding ring is co-rotated such that the part of the guiding lines located between the guiding ring and the second ends of the guiding lines forms a part of the coil-like orientation of the guiding lines, and the guiding ring being rotated such that when the line guide system is moved into the first rotation condition, the part of the guiding lines located between the guiding ring and the second ends of the guiding lines forms the second coil-like segments of the guiding lines.
Moreover, disclosed herein is a machine tool comprising a line guide system according to the invention.
The machine tool may have working equipment that is disposed on the second body and rotatable with the latter relative to the first body whereby the supply lines guided by the line guide system serve to supply electric signals and fluids to the working equipment or lead electrical signals and fluids away from the working equipment.
Furthermore, disclosed herein is a machine tool comprising a line guide system according to one of the described or following embodiments.
In the following the invention will be described in more detail with reference to the Figures in an exemplary embodiment, wherein:
a-2d show the line guide system shown in
a-3b show cross-sectional views of a part of guiding line fixation portions of the line guide system shown in
a-5d show perspective views of various rotation conditions of the line guide system shown in
a-7b show cross-sectional views of a part of supply line fixation portions of the line guide system shown in
In the figures, identical or corresponding areas, components, or component assemblies are designated by the same reference numerals.
When the second body 3 is rotated about the rotational axis D with respect to the first body 2, the geometric shapes of the extensions of the guiding lines 4 along the outer surface of the first body 2 change from the first fixation portion 6 toward the second fixation portion 8.
The rotation condition shown in
When the second body 3 is rotated clockwise, starting from the initial position condition (shown in
When, on the other hand, the second body 3 is rotated counterclockwise, starting from the initial position condition (shown in
When the second body 3 is continued to be rotated counterclockwise, starting from the rotation condition shown in
The change of the geometric extensions of the guiding lines 4 according to the respective rotation conditions is possible without any problems because the guiding lines 4 have a flexible structure. For example, the guiding lines 4 may be guiding chains that can be moved in three spatial directions (e.g., what are called Triflex® R guiding chains).
Based on the behavior of the guiding lines 4 in the respective rotation conditions described in
As can be seen in
As can be taken from
The line guide system 1 has a distributor ring 35 connected to the first body 2 at the lower end thereof. Line terminals 36 are provided in the distributor ring 35 which are connected to the supply lines 31. The distributor ring 35 is connected to the first body 2 via fasteners 37 (e.g., screws). The first fixation portion 6 has bores 38 by means of which the fasteners can be reached. Thus, it is not necessary to fix the distributor ring 35 to the first body 2 from the opposite side.
The second body 3 has further guiding elements 19 in the second fixation portion 8 which surround the second ends 7 of the guiding elements 4 on both sides and allow some clearance of the guiding lines 4 along a peripheral direction around the rotational axis D. The guiding elements 19 each have a convex extension directed toward the guiding lines 4 to which the guiding lines 4 can fit tightly. In the first rotation condition, the guiding lines 4 fit tightly to one respective guiding element 19, and in the first rotation condition to the respective other one. Thus, it is possible to prevent the guiding lines 4 from rotating and bending too strongly in the second fixation portion 8.
Furthermore,
The rotation condition shown in
If the second body 3, starting from the initial position state shown in
If, on the other hand, the second body 3, starting from the initial position state shown in
When the second body 3, starting from the rotation condition shown in
The rotation condition shown in
It can be taken from
According to an embodiment disclosed herein, the line guide system 1 and the line guide system 1′ may be combined to form a combined line guide system 1″, which is shown in
In this embodiment, the first body 2 may have a first hollow body 22 formed around the rotational axis D and a second hollow body 23 formed around the first hollow body 22. At least one of the guiding lines 4 extends inside a first cavity 24 formed between the first hollow body 22 and the second hollow body 23. The first body 2 in this embodiment has a third hollow body 25 formed around the second hollow body 23. At least one of the guiding lines 4 extends inside a second cavity 26 formed between the second hollow body 23 and the third hollow body 25. Inside the first hollow body 22, an input shaft of a working spindle can be guided, if necessary, which is mounted to the system 1″ at the side of the head 29. In this embodiment, a length L1 of the first and second hollow bodies 22, 23 is longer than a length L2 of the third hollow body 25.
In this embodiment, the second body 3 has a first part 27 disposed at the upper end of the first cavity 24 and disposed to be rotatable about the first hollow body 22 (ring-shaped element). The second ends 7 of those guiding lines 4 that extend inside the first cavity 24 are fixed to the first part 27. Further, the second body 3 has a second part 28 which is disposed at the upper end of the second cavity 26 so as to be rotatable about the second hollow body 23 and to which second ends of the guiding lines 4 are fixed which extend through the second cavity 26. The second part 28 of the second body 3 is also a ring-shaped element.
The guiding lines extending through the first hollow body 24 may receive lines that transport media, such as fluid media, and the guiding lines 4 extending through the second hollow body 26 may receive lines transporting electric signals. This provides a particular advantage when the guiding lines transporting electric signals have to receive a large number of cables because the twisting of these guiding lines 4 is not as easy as the twisting of those guiding lines that transport media. As the second cavity 26 is further spaced apart radially from the rotational axis D than the first cavity 24, the guiding lines 4 receiving supply lines for transporting electric signals need not be twisted so strongly.
Accordingly, in
Inside the interior 33″ of the first hollow body 22 of the line guide system 1″, an input shaft may be provided. This applies analogously to interiors 33/33′ of the first body 2 of the line guide system 1/1′, should the former be formed as a hollow shape.
The invention is not confined to the presented exemplary embodiments but comprises further combinations of the structural details presented in this description so as to create further exemplary embodiments according to a required use based on the knowledge of a person skilled in the art.
Number | Date | Country | Kind |
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10 2012 002 093.7 | Feb 2012 | DE | national |