U.S. patent application number 15/901313 was filed with the patent office on 2018-06-28 for machine tool having a machine magazine and a background magazine.
The applicant listed for this patent is CHIRON-WERKE GmbH & Co. KG. Invention is credited to Claus Eppler, Dirk Prust.
Application Number | 20180178337 15/901313 |
Document ID | / |
Family ID | 46639534 |
Filed Date | 2018-06-28 |
United States Patent
Application |
20180178337 |
Kind Code |
A1 |
Prust; Dirk ; et
al. |
June 28, 2018 |
MACHINE TOOL HAVING A MACHINE MAGAZINE AND A BACKGROUND
MAGAZINE
Abstract
In a machine tool having at least one tool spindle which is
displaceable in relation to a device for holding workpieces in at
least one of three spatial directions and in which the tools
(W1-W7) for processing the workpieces can be chucked, there are
provided a machine magazine (36) in which tools (W1-W7) provided
for exchange in the tool spindle (23) are kept in store and a
background magazine (31) in which tools (W1-W7) provided for
exchange in the machine magazine (36) are kept in store. In the
machine magazine (36), not more than four storage places (42, 43,
44, 45) for accommodating tools (W1-W7) are provided (FIG. 2).
Inventors: |
Prust; Dirk; (Tuttlingen,
DE) ; Eppler; Claus; (Messkirch, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CHIRON-WERKE GmbH & Co. KG |
Tuttlingen |
|
DE |
|
|
Family ID: |
46639534 |
Appl. No.: |
15/901313 |
Filed: |
February 21, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14196262 |
Mar 4, 2014 |
9925631 |
|
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15901313 |
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PCT/EP2012/065666 |
Aug 10, 2012 |
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14196262 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y10T 483/179 20150115;
Y10T 483/1733 20150115; B23Q 3/15766 20130101; B23Q 3/15526
20130101; Y10T 483/1891 20150115; Y10T 483/10 20150115; B23Q
3/15539 20161101; Y10T 483/1855 20150115; B23Q 3/15724 20161101;
B23Q 3/15706 20130101 |
International
Class: |
B23Q 3/157 20060101
B23Q003/157; B23Q 3/155 20060101 B23Q003/155 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 9, 2011 |
DE |
10 2011 113 311.2 |
Claims
1-35. (canceled)
36. A machine tool comprising at least one tool spindle, a device
for holding at least one workpiece, a machine magazine, and a
background magazine, said at least one tool spindle being
displaceable in at least one of three spatial directions in
relation to said device for holding said at least one workpiece,
said at least one tool spindle being adapted for exchangeably
chucking tools for processing a workpiece, wherein in said machine
magazine tools are provided for exchange into said at least one
tool spindle, in said background magazine tools are provided for
exchange into the machine magazine, for the or each tool spindle
three storage places for accommodating tools being provided in the
machine magazine, wherein the machine magazine is configured as a
chain magazine having a chain on which the storage places are
arranged.
37. A machine tool comprising at least one tool spindle, a device
for holding at least one workpiece, a machine magazine, and a
background magazine, said at least one tool spindle being
displaceable in at least one of three spatial directions in
relation to said device for holding said at least one workpiece,
said at least one tool spindle being adapted for exchangeably
chucking tools for processing a workpiece, wherein in said machine
magazine tools are provided for exchange into said at least one
tool spindle, in said background magazine tools are provided for
exchange into the machine magazine, for the or each tool spindle
four storage places for accommodating tools being provided in the
machine magazine, wherein the machine magazine is configured as a
chain magazine having a chain on which the storage places are
arranged.
38. The machine tool of claim 37, wherein the machine magazine
comprises for the or each tool spindle two pairs of two storage
places, which storage places in a pair thereof are each spaced
apart from one another at a first distance, wherein two adjacent
storage places belonging to different pairs of storage places are
spaced apart from one another at a second distance which is larger
than the first distance.
39. The machine tool according to claim 36, wherein said machine
tool comprises a slide which is displaceable in a first spatial
direction and on which a column which is displaceable in a second
spatial direction is mounted, and on which column a spindle head
which is displaceable in a third spatial direction is mounted, the
or each tool spindle being rotatably mounted in said spindle head,
the machine magazine being mounted on the slide.
40. The machine tool according to claim 37, wherein said machine
tool comprises a slide which is displaceable in a first spatial
direction and on which a column which is displaceable in a second
spatial direction is mounted, and on which column a spindle head
which is displaceable in a third spatial direction is mounted, the
or each tool spindle being rotatably mounted in said spindle head,
the machine magazine being mounted on the slide.
41. The machine tool according to claim 39, wherein the machine
magazine is mounted at said slide in such a manner that it is
displaceable between a tool-change position, in which tools are
exchanged between the machine magazine and the tool spindle, and a
tool-interchange position, in which tools are exchanged between the
background magazine and the machine magazine.
42. The machine tool according to claim 40, wherein the machine
magazine is mounted at said slide in such a manner that it is
displaceable between a tool-change position, in which tools are
exchanged between the machine magazine and the tool spindle, and a
tool-interchange position, in which tools are exchanged between the
background magazine and the machine magazine.
43. A method for changing tools at a machine tool comprising at
least one tool spindle, a device for holding at least one
workpiece, a machine magazine, and a background magazine, said at
least one tool spindle being displaceable in at least one of three
spatial directions in relation to said device for holding said at
least one workpiece, said at least one tool spindle being adapted
for exchangeably chucking tools for processing a workpiece, wherein
in said machine magazine tools are provided for exchange into said
at least one tool spindle, in said background magazine tools are
provided for exchange into the machine magazine, for the or each
tool spindle three storage places for accommodating tools being
provided in the machine magazine, the machine magazine being
configured as a chain magazine having a chain on which the storage
places are arranged, in which method the at least one tool spindle
is moved into a tool-change position in which tools are exchanged
between the machine magazine and the at least one tool spindle, and
and wherein a tool-interchange position is provided at which tools
are exchanged between the background magazine and the machine
magazine.
44. A method for changing tools at a machine tool comprising at
least one tool spindle, a device for holding at least one
workpiece, a machine magazine, and a background magazine, said at
least one tool spindle being displaceable in at least one of three
spatial directions in relation to said device for holding said at
least one workpiece, said at least one tool spindle being adapted
for exchangeably chucking tools for processing a workpiece, wherein
in said machine magazine tools are provided for exchange into said
at least one tool spindle, in said background magazine tools are
provided for exchange into the machine magazine, for the or each
tool spindle four storage places for accommodating tools being
provided in the machine magazine, the machine magazine being
configured as a chain magazine having a chain on which the storage
places are arranged, in which method the at least one tool spindle
is moved into a tool-change position in which tools are exchanged
between the machine magazine and the at least one tool spindle, and
and wherein a tool-interchange position is provided at which tools
are exchanged between the background magazine and the machine
magazine.
45. The method according to claim 44, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a previously used tool which has previously been
deposited into the machine magazine by the tool spindle, is removed
at the tool-interchange position from the machine magazine and
stored into said background magazine.
46. The method according to claim 43, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a previously used tool which has previously been
deposited into the machine magazine by the tool spindle, is removed
at the tool-interchange position from the machine magazine and
stored into said background magazine, and a new tool (W4, W5) is
deposited from the background magazine into a vacant storage place
in the machine magazine.
47. The method according to claim 43, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a new tool is provided by the background magazine at the
tool-interchange position.
48. The method according to claim 46, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a new tool is provided by the background magazine at the
tool-interchange position.
49. The method according to claim 43, wherein the tool change
between the tool spindle and the machine magazine takes place
simultaneously with the tool interchange between the machine
magazine and the background magazine.
50. The method according to claim 44, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a previously used tool which has previously been
deposited into the machine magazine by the tool spindle, is removed
at the tool-interchange position from the machine magazine and
stored into said background magazine.
51. The method according to claim 44, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a previously used tool which has previously been
deposited into the machine magazine by the tool spindle, is removed
at the tool-interchange position from the machine magazine and
stored into said background magazine, and a new tool is deposited
from the background magazine into a vacant storage place in the
machine magazine.
52. The method according to claim 44, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a new tool is provided by the background magazine at the
tool-interchange position.
53. The method according to claim 51, wherein, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes said workpiece
with said current tool, and thereafter returns to the tool-change
position, a new tool is provided by the background magazine at the
tool-interchange position.
54. The method according to claim 44, wherein the tool change
between the tool spindle and the machine magazine takes place
simultaneously with the tool interchange between the machine
magazine and the background magazine.
55. The method of claim 43, wherein the used tool is the tool which
has been deposited by the tool spindle into said machine magazine
last.
56. The method of claim 55, wherein the used tool is the tool which
has been deposited by the tool spindle into said machine magazine
next to last.
57. The method of claim 44, wherein the used tool is the tool which
has been deposited by the tool spindle into said machine magazine
last.
58. The method of claim 57, wherein the used tool is the tool which
has been deposited by the tool spindle into said machine magazine
next to last.
59. The method of claim 43, wherein the new tool is the tool which
is to be used next by the tool spindle.
60. The method of claim 43, wherein the new tool is the tool which
is to be used next but one by the tool spindle.
61. The method of claim 44, wherein the new tool is the tool which
is to be used next by the tool spindle.
62. The method of claim 44, wherein the new tool is the tool which
is to be used next but one by the tool spindle.
63. The method of claim 43, wherein the machine magazine comprises
for the or each tool spindle two pairs of two storage places, which
storage places in a pair thereof are each spaced apart from one
another at a first distance, wherein two adjacent storage places
belonging to different pairs of storage places are spaced apart
from one another at a second distance which is larger than the
first distance, and wherein a tool change is effected by the
machine magazine moving across the first distance, and, a tool
interchange is effected by the machine magazine moving across the
second distance.
64. The method of claim 44, wherein the machine magazine comprises
for the or each tool spindle two pairs of two storage places, which
storage places in a pair thereof are each spaced apart from one
another at a first distance, wherein two adjacent storage places
belonging to different pairs of storage places are spaced apart
from one another at a second distance which is larger than the
first distance, and wherein a tool change is effected by the
machine magazine moving across the first distance, and, a tool
interchange is effected by the machine magazine moving across the
second distance.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation application of co-pending
international patent application PCT/EP2012/065666, filed Aug. 10,
2012 and designating the United States, which was published in
German as WO 2013/034388 A2, and claims priority to German patent
application DE 10 2011 113 311.2, filed Sep. 9, 2011. These
priority applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a machine tool having at
least one tool spindle which is displaceable in at least one of
three spatial directions in relation to a device for holding
workpieces, and in which tool spindle tools for processing the
workpieces can be chucked, having a machine magazine in which tools
provided for exchange into the at least one tool spindle are kept
in store, and having a background magazine in which tools provided
for exchange into the machine magazine are kept in store.
[0003] The invention further relates to a method for a tool change
on a machine tool having at least one tool spindle which is
displaceable in at least one of three spatial directions in
relation to a device for holding workpieces, and in which tool
spindle tools for processing the workpieces can be chucked, having
a machine magazine in which tools provided for exchange into the at
least one tool spindle are kept in store, and having a background
magazine in which tools provided for exchange into the machine
magazine are kept in store, in which method the at least one tool
spindle is moved into a tool-change position in which tools are
exchanged between the machine magazine and the at least one tool
spindle, wherein a tool-interchange position is provided at which
tools are exchanged between the background magazine and the machine
magazine.
[0004] A machine tool of this type and a method of the
aforementioned type are disclosed in DE 102 25 143 A1.
[0005] In the context of the present invention, "a tool spindle
which is displaceable in at least one of three spatial directions
in relation to a device for holding workpieces" is understood to
mean an arrangement in which the tool spindle and the workpiece are
displaceable in relation to one another in at least one of the
three orthogonal spatial axes x, y and z. When the machine tool is
what is referred to as a travelling-column machine, all three
directions of movement are implemented in the tool spindle, the
latter thus being advanced to the workpiece in the x, y and z
directions.
[0006] However, it is also possible here to implement one or two
directions of movement, i.e. in particular the x and y directions,
in the workpiece.
[0007] It is, however, irrelevant for the implementation of the
present invention how the axes of movement are distributed between
the tool spindle and the workpiece.
[0008] If all three directions of movement are implemented in the
tool spindle, the machine tool is preferably a travelling-column
machine having a vertical-axis tool spindle; the tool spindle is
thus advanced to the workpiece in the vertical direction. However,
it is also possible for the tool spindle to be aligned
horizontally, such that advancing takes place horizontally.
[0009] It is furthermore possible for further pivot axes or
rotation axes to be arranged either in the tool spindle and/or in
the workpiece.
[0010] Without departing from the scope and the advantages and
functionalities of the present invention, the machine tool here may
be equipped with one, two, four or even more tool spindles. The
plurality of tool spindles are preferably synchronously displaced
in relation to one another, they are preferably rigidly coupled to
one another and in this event serve for the simultaneous and
contour-identical processing of as many workpieces as there are
tool spindles.
[0011] The present invention starts from a machine tool in which
both a machine magazine and a background magazine are provided.
[0012] A multiplicity of machine tools having tool magazines are
known from the prior art. It is customary for the tool magazine to
be attached to the machine tool; it may be configured, for example,
as a chain magazine or a disc magazine.
[0013] In machine tools of this type, a variety of tools which are
successively inserted into the tool spindle are kept ready in order
to perform specific processing operations on a workpiece. The tool
change between the tool magazine and the tool spindle takes place
in this case by a variety of ways and means.
[0014] For example, DE 197 24 635 A1 discloses a machine tool
having a background magazine in the form of a disc magazine in
which a double gripper which conveys tools back and forth between
the disc magazine and the working space of the machine tool is
provided. The double gripper in this case removes a tool from the
disc magazine and is then pivoted together with that tool into the
working space. There, by way of the pick-up method, the tool
spindle approaches the double gripper, deposits the tool that is
currently chucked in the tool spindle into the free gripper of the
double gripper and then grips the tool that was previously inserted
into the double gripper from the disc magazine.
[0015] In addition to the disc magazine, the known machine tool
also has a machine magazine which is located on the machine tool
and from which tools can be likewise changed into the tool spindle.
The tool which has been exchanged from the disc magazine into the
tool spindle by means of the double gripper can also be deposited
into the machine magazine in this manner with the aid of the tool
spindle.
[0016] A further machine tool, in which the machine magazine is
configured as a chain magazine, is disclosed in DE 190 19 446 A1.
To change tools, the chain magazine is pivoted into the working
space of the machine tool where a tool change to the tool spindle
takes place by way of the pick-up method.
[0017] In the machine tools described so far, only a specific
number of tools can be stored intermediately in the respective
machine magazine, such that it is often necessary for the workpiece
to be re-chucked on another machine tool in order to be able to
carry out processing operations with further tools here.
[0018] In this context, DE 197 24 635 A1 describes a machine tool
in which an external tool magazine is provided as a background
magazine by way of which further tools are provided.
[0019] A similar design is also shown in DE 100 20 801 A1. The
background magazine is designed as a rack magazine in which a very
large number of tools can be stored intermediately. A transfer
device which removes tools from the rack magazine and conveys them
to a transfer position which is stationary in relation to the rack
magazine is provided on the rack magazine.
[0020] This transfer position is also served by a double gripper
which is pivotably mounted on the machine frame and which, in the
transfer position, can deliver a tool to the transfer device or
remove a new tool from the transfer device. Having this new tool,
the double gripper then pivots close to the working space of the
machine tool where it provides the new tool for a tool change by
way of the pick-up method.
[0021] Once the tool spindle has terminated a processing operation,
it travels to the spindle position of the double gripper and
initially deposits the tool which has been employed so far into the
free gripper. Thereafter, the tool spindle grips the tool which has
been newly brought from the rack magazine and again travels to the
working space, where processing of the workpiece continues using
the new tool.
[0022] In theory, any number of available tools are possible with
this design, such that the problem of a limited number of available
tools that exists for reasons of space in machine magazines is
solved by the background magazine together with the transfer device
and the double gripper.
[0023] The known construction is, however, complex in its design,
the tool change not being sufficiently rapid for many
applications.
[0024] Proceeding therefrom, DE 102 25 143 A1 discloses a machine
tool which combines the principle of the machine magazine which,
although having a limited number of stored tools, has the potential
for rapid tool changes, with the advantages of the background
magazine in which the storage potential for any number of tools can
be utilized.
[0025] The known machine tool thus enables, on the one hand, a
rapid tool change by means of the machine magazine, wherein tools
can be removed from the background magazine and new tools can be
introduced into the machine magazine, virtually expanding the
machine magazine as it were to the size of the background
magazine.
[0026] In the known machine tool, the machine magazine is
configured as a chain magazine which is arranged on the y-slide of
the machine tool so as to ride therewith, which machine tool is
configured as a travelling-column machine. For a tool change, this
chain magazine is displaced into the working space of the machine
tool, whereby, for a tool interchange with the background magazine,
it has to be moved into a transfer position.
[0027] Despite this machine tool meeting many requirements on
account of the, in principle, unlimited number of tools and the
rapid tool change, it is in the case of many applications still not
suited to particularly rapid tool-change times and, in particular,
to particularly rapid chip-to-chip times.
SUMMARY OF THE INVENTION
[0028] In view of the above, it is among others one object of the
present invention to provide a machine tool of the type mentioned
at the outset, in which, in principle, an unlimited number of tools
can be rapidly exchanged into the at least one tool spindle without
the processing times of the new machine tool being compromised in
the case of a high throughput of tools. Furthermore, the new
machine tool should be of simple design and require little
space.
[0029] According to the invention, this object is achieved in the
case of the machine tool mentioned at the outset in that not more
than four storage places for accommodating tools are provided in
the machine magazine for the or each tool spindle.
[0030] In the case of the method mentioned at the outset, this
object is accordingly achieved according to the invention in that a
maximum of four tools for the or each tool spindle are situated in
the machine magazine at the same time.
[0031] At first sight, it does not appear to be constructive to
employ a "small" machine magazine in which only three or four tools
for the or each tool spindle are temporarily stored, instead of a
real machine magazine that can temporarily store 20, 30 or 40
tools.
[0032] The inventor of the present invention has, however,
recognized that, on account of the interaction between the machine
magazine and the tool spindle, it is also possible to provide the
theoretically unlimited number of tools for the tool spindle from
the background magazine and nevertheless maintain the rapid tool
change, even in the case of three or four tool storage places in
the machine magazine.
[0033] The inventor of the present invention has furthermore
specifically recognized that the machine magazine has sufficient
time to perform a tool interchange with the background magazine
during the main time, i.e. the time during which the tool spindle
having the currently chucked tool travels from the tool-change
position to the workpiece, processes said workpiece and is then
returned to the tool-change position.
[0034] Specifically, it is merely necessary for each operation to
transfer an already used tool from the machine magazine to the
background magazine and to insert a new tool from the background
magazine into the machine magazine.
[0035] During this main time there is ample time to correspondingly
displace the background magazine, such that tools can be deposited
and exported.
[0036] Only a maximum of four tools for the or each tool spindle
are then temporarily stored in the machine magazine, i.e. the last
tool, the tool being currently employed and the tool to be employed
next, the next but one or the next to last tool likewise being able
to be stored.
[0037] On account of this, a tool interchange is possible at the
machine magazine during the main time, which is longer in
comparison to the secondary time. Only the tool change on the tool
spindle is carried out during the secondary time.
[0038] The tool change on the tool spindle or spindles and the tool
interchange with the background magazine may take place
simultaneously, the interchange between the machine magazine and
the background magazine having to be terminated at the latest when
the or each tool spindle has deposited the or each tool which has
been used last into the machine magazine.
[0039] According to one object, the tool change on the tool spindle
or spindles and the tool change on the background magazine takes
place in a synchronous manner, as the motion sequences can then be
mechanically coupled, this reducing the design complexity and the
control complexity.
[0040] A particular advantage of the new machine tool is the low
weight of the machine magazine, as it needs to keep available only
four storage places for the maximum of four tools. These four
storage places may be configured on a disc magazine or on a chain
magazine.
[0041] According to another object, the new method may even be
employed in existing machine tools, namely if all storage places
except for four chain places are removed from the machine tool
known from DE 102 25 143 A1 mentioned at the outset, with the
result that the weight of the known machine magazine is obviously
reduced.
[0042] Various timing advantages result in the case of an
considerably reduced weight of the machine magazine. On the one
hand, the machine magazine itself can be moved, i.e. advanced, much
more rapidly; given the lower weight, the acceleration and
deceleration times are much shorter than in the case of machine
magazines which have to move along 20 or 40 tools at corresponding
tool storage places.
[0043] On the other hand, however, the tool spindle itself can be
more rapidly displaced, since the mass of the machine magazine
which is entrained via the slide at least in the x-direction is
obviously lower than in the prior art, such that an improved
acceleration and thus shorter displacement times can also be
achieved here.
[0044] Finally, approach and departure of the machine magazine to
and from the tool-change position can also be implemented in a more
rapid manner.
[0045] This leads to both the main time and also the secondary time
being reduced, leading to a higher throughput in the case of the
new machine tool.
[0046] According to a further object, the new machine tool is very
simple to control. No special attention is required any longer with
respect to the sequence of the tools in the machine magazine, since
only ever two, three or four tools per tool spindle are present in
the machine tool at any time.
[0047] Also, the sequence of the tools in the background magazine
is of only minor relevance for the speed of the entire machining
process, since during the main time the background magazine has
sufficient time for providing the tool which has in each case to be
changed next into the machine magazine.
[0048] It goes without saying that it is possible in this case to
deposit the tools in the background magazine such that their
spatial arrangement also corresponds to the temporal sequence in
which they are to be used in the respective process.
[0049] This method is, in principle, known from the prior art.
Accordingly, for example DE 43 11 469 A1 discloses a method for a
tool change in which an empty position is created beside the tool
to be changed, the tool to be interchanged being deposited in said
empty position. The empty position is created in that a tool is
temporarily stored in a special gripper.
[0050] DE 10 2006 028 A describes a refinement of this tool-change
strategy, in which the tools, when placed back into the machine
magazine, are deposited substantially in that sequence in which
they are employed in the temporal order of processing.
[0051] This way of sorting tools may also be used in the new
machine tool and the new method, but it is now no longer required
that a separate gripper be employed for the temporary storage of
tools which have been removed from storage in order to provide
empty positions.
[0052] It is indeed possible in principle, to provide so many empty
positions in the background magazine that a corresponding sorting
of the tools in the temporal order during the first pass in the
processing of a new workpiece takes place, for all intents and
purposes, automatically.
[0053] According to the invention, the machine magazine thus has
either three storage places or four storage places for each tool
spindle.
[0054] It is of advantage in both cases that moving or advancing of
the machine magazines is limited to a minimum, since each tool is
deposited back into the storage place from which it was previously
removed by the tool spindle.
[0055] Yet another advantage in terms of speed results in
particular when only three storage places are provided for each
tool spindle, since only three instead of four entrained storage
spaces for each tool spindle are now required, again reducing the
moving mass of the machine magazine.
[0056] According to a further object, the machine magazine has for
each tool spindle two pairs of two storage places, which storage
places are each spaced apart from one another at a first distance,
wherein two adjacent storage places belonging to different pairs of
storage places are spaced apart from one another at a second
distance which is larger than the first distance.
[0057] It is advantageous in the case of this measure that two
storage places which are adjacent to one another in one pair are
employed to release the tool to be interchanged from the tool
spindle into the first storage place and to pick up the current
tool which is to be newly employed from the spatially close second
storage place.
[0058] Here, the tool magazine needs to be displaced only over a
very short path, such that the entire tool change takes place very
rapidly and the secondary time for interchanging of tools on the
tool spindle which, for all intents and purposes, elapses in an
unproductive manner can yet again be reduced.
[0059] In other words, during the tool change on the tool spindle,
the machine magazine is displaced across the first distance and,
for the tool interchange between the machine magazine and the
background magazine, is displaced across the longer second
distance.
[0060] According to an object of the method, during the period of
time in which the tool spindle carrying a current tool approaches a
workpiece from the tool-change position, processes therewith said
workpiece, and thereafter returns to the tool-change position, an
used tool which has previously been deposited in the machine
magazine by the tool spindle is removed at the tool-interchange
position and preferably a new tool is deposited into a vacant
storage place in the machine magazine.
[0061] On the other hand, it is an object that, during the period
of time in which the tool spindle carrying a current tool
approaches a workpiece from the tool-change position and processes
said workpiece and thereafter returns to the tool-change position,
a new tool is provided by the background magazine at the
tool-interchange position.
[0062] In the event that the tool change between the tool spindle
and the machine magazine and also between the machine magazine and
the background magazine takes place simultaneously, the background
magazine provides a new tool at the tool-interchange position with
the machine magazine during the main time.
[0063] In this case, the used tool is either the tool which has
been deposited last or the tool which has been deposited next to
last, the new tool being the tool which is to be used next or the
tool which is to be used next but one.
[0064] These measures offer the already mentioned advantage that a
new tool can be provided in or for the machine magazine during the
main time, such that a very rapid tool change is possible on the
tool spindle during the secondary time.
[0065] Owing to the low weight of the machine magazine, the main
time can also be reduced once again, since the tool spindle can be
displaced very rapidly.
[0066] On the other hand, owing to the small number of tools in the
machine magazine, the secondary time is also reduced, since the
tool change can be planned to be optimally rapid.
[0067] In general, it is an object that the machine tool has a
slide which is displaceable in a first spatial direction and on
which a column which is displaceable in a second spatial direction
is mounted, and on which column a spindle head which is
displaceable in a third spatial direction is mounted, the tool
spindle being rotatably mounted in said spindle head, and that the
machine magazine is mounted on the slide, wherein the machine
magazine is preferably mounted in such a manner that it is
displaceable between a tool-change position, in which tools are
exchanged between the machine magazine and the tool spindle, and a
tool-interchange position, in which tools are exchanged between the
background magazine and the machine magazine.
[0068] In the case of these measures which are, in principle,
already known from DE 102 25 143 A1 mentioned at the outset, it is
advantageous that they describe what is referred to as a
travelling-column machine having a vertical tool spindle, which in
itself already makes for very short tool-change times and very
short secondary times and optimally short main times.
[0069] It should also be mentioned that only a very small space
requirement for the machine magazine exists in the new machine
tool, whereas essentially any amount of space is available for the
background magazine, which can be constructed on the machine frame
or separately from the machine frame. The background magazine may
be designed as a rack magazine, for example, any other type of
background magazine also being employable according to the
invention.
[0070] Further advantages emerge from the description and the
appended drawings.
[0071] It goes without saying that the features mentioned above and
yet to be explained in the following can be utilized not only in
the combination which is stated in each case, but also in other
combinations or on their own, without departing from the scope of
the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0072] Embodiments of the invention are illustrated in the drawing
and are explained in more detail in the following description. In
the drawing:
[0073] FIG. 1 shows a schematic side view of the new machine
tool;
[0074] FIG. 2 shows, in a schematic plan view, the interaction of
the tool spindle, the machine magazine and the background magazine
for a first embodiment of the machine magazine;
[0075] FIGS. 3a-3d show the method steps for the tool change and
the tool interchange in the machine magazine of FIG. 2;
[0076] FIG. 4 shows a second embodiment of a machine magazine, in
an illustration like FIG. 2;
[0077] FIGS. 5a-5e show the individual steps in the tool change and
the tool interchange for the machine magazine of FIG. 4;
[0078] FIG. 6 shows a third embodiment of a machine magazine, in an
illustration like in FIG. 2;
[0079] FIGS. 7a-7d show the individual steps for the tool change
and the tool interchange in the machine magazine of FIG. 6;
[0080] FIG. 8 shows a fourth embodiment of a machine magazine, in
an illustration like FIG. 4; and
[0081] FIG. 9 shows an embodiment for a machine tool having two
tool spindles and 2 times 4 storage places, in a depiction as in
FIG. 4.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0082] In FIG. 1, a machine tool, identified by 10, is shown very
schematically in a side view. The machine tool 10 is a
travelling-column machine, in which a slide 12 which is
displaceable on guides 14 in the x-direction 15 is arranged on a
machine frame 11.
[0083] A travelling column 16 is displaced on the x-slide 12 on
guides 17 which extend in the y-direction 18.
[0084] A slide 19 which is displaceable in the z-direction 21, i.e.
is adjustable for height, is arranged on the travelling column
16.
[0085] The slide 21 carries a spindle head 22 in which at least one
tool spindle 23 is mounted so as to be rotatable about a rotation
axis 24 in a manner known per se. The spindle head may
alternatively carry two or four tool spindles with which two or
four workpieces can then be processed in a simultaneous and
contour-identical manner.
[0086] On its lower end, the tool spindle 23 has a typical tool
holder for chucking a tool 25 with which a workpiece 26 is
processed, which workpiece is retained in a device 27 which is
arranged on a workpiece table 28 in the working space 29.
[0087] In this manner, the machine tool 10, with the aid of a tool
25, can process the workpiece 26 in the three orthogonal spatial
axes 15, 18, 21.
[0088] A background magazine 31 in which numerous tools 25 can be
temporarily stored is mounted separately from the machine frame 11
behind the machine tool 10.
[0089] It goes without saying that it is also possible for the
background magazine 31 to be fixedly connected to the machine frame
11.
[0090] It should be noted, merely for the sake of good order, that
the invention is also implementable with a machine tool in which
the or each tool spindle 23 is not oriented in the vertical axis
but in the horizontal axis, wherein furthermore not all three axes
of movement 15, 18, 21 have to be implemented in the tool 25; at
least one axis of movement can also be implemented in the workpiece
26, as is known, in principle, from the prior art.
[0091] A transfer device 32 which is schematically illustrated and
which is displaced on the background magazine along three
displacement axes 33, 34, 35 which extend in an orthogonal manner
in relation to one another is arranged on the background magazine
31, said transfer device 32 depositing tools into or removing them
from the background magazine 31.
[0092] The background magazine 31 is a rack magazine in the
illustration shown.
[0093] A machine magazine 36 which is arranged in an entrained
manner on the x-slide 12 interacts with the background magazine 31.
This machine magazine 36 is, on the one hand, displaceable in the
direction indicated by a double arrow 37 such that, with its front
end, it protrudes into the working space 29 and provides a
tool-change position 38 for the tool spindle 23 there. The
tool-change position 38 is illustrated with dashed lines in FIG.
1.
[0094] In the position of the machine magazine 36 which is
illustrated with solid lines, the machine magazine 36 is situated
with its rear end in a tool-interchange position 39 in which, with
the aid of the transfer device 32, tools 25 can be interchanged
between the machine magazine 36 and the background magazine 31.
[0095] In the case of the machine magazine 36 in FIG. 1, the
arrangement has been chosen such that the machine magazine 36 can
temporarily store three or, at most, four tools 25, i.e. has only
three or four storage places.
[0096] In FIG. 2, the interaction of the machine magazine 36 with
the tool spindle 23, on the one hand, and the background magazine
31, on the other hand, is shown in a plan view and in a very
schematic manner.
[0097] The machine magazine 36 is a chain magazine having a
revolving chain 41, on which four storage places 42, 43, 44 and 45
are provided.
[0098] The tool spindle 23 has, in a known manner, a tool holder 46
into which and from which tools 25 can be exchanged at the
tool-change position 38.
[0099] In the background magazine 31, which is likewise illustrated
in a schematic manner, seven storage places 47 for tools are
provided, the storage places 1 to 4 being currently empty, the
tools W5, W6 and W7 being in the storage places 5 to 7. The tools
W1, W3 and W4 are situated in the storage places 44, 42 and 45 of
the machine magazine 36, whereas the tool W2 is chucked in the tool
holder 46 and has been used for processing a workpiece 26 and is
now to be interchanged.
[0100] It goes without saying that the storage places 47 do not
necessarily have to be arranged in the background magazine 31 in
the same chronological sequence in which the tools 25 are
successively used; the chronological illustration in FIG. 2 has
been chosen simply for the purpose of clarity.
[0101] FIGS. 3a to 3d now show how the tool W2 is exchanged with
tool W3 and the tool W1 is simultaneously guided back into the
background magazine 31 and the tool W5 is deposited into the
machine magazine 36 in its place.
[0102] It can be seen in FIG. 3a that initially the tool W2 from
the tool holder 46 has been deposited into the storage place
43.
[0103] Thereafter, the machine magazine 31 is advanced. The storage
places 42, 43, 44, 45 are indexed in the clockwise direction by one
position, such that the situation in FIG. 3b results.
[0104] Next, the tool W3 is now transferred into the tool holder
46, such that the situation of FIG. 3c results. Thereafter, the
tool W1 is removed from the storage place 45 and transferred into
the background magazine 31; see FIG. 3c.
[0105] Finally, the new tool W5 from the rack magazine 31 is
deposited into the storage place 44; see FIG. 3d.
[0106] As a result, a similar situation is encountered in FIG. 3d
as in FIG. 2, only now the tool W3 is the tool currently being
employed, whereas the tool W2 is the next to be deposited in the
background magazine 31 from which the tool W6 is then removed.
[0107] The tool W4 is the next to be used, whereas the tool W5 is
the next but one to be used.
[0108] In the method for a tool change described so far, it is
particularly advantageous that the machine magazine 31 is required
to perform only a few indexing movements, since each tool is
deposited again by the tool spindle 23 precisely from where it was
removed.
[0109] Furthermore, the already mentioned advantages result in that
only a very small number of storage places 42, 43, 33 and 45 have
to be kept available, such that both indexing of the machine
magazine 36 and the movement of the y-slide 12 take place very
rapidly.
[0110] The method steps which have led from FIG. 2 via FIG. 3a and
FIG. 3b to FIG. 3c are what are referred to as secondary time,
during which processing of the workpiece is not possible.
[0111] During removing of the tool W1 and inserting of the tool W5,
as is shown in FIGS. 3c and 3d, the tool spindle 23 can, however,
process a workpiece with the tool W3; this is what is referred to
as the main time.
[0112] The steps in FIGS. 3b and 3c and the steps in FIGS. 2 and 3d
may also take place simultaneously, in particular the tool changes
on the tool-change position 38 and on the tool-interchange position
39 are mechanically synchronized.
[0113] A machine magazine 36 which likewise has four storage places
42, 43, 44 and 45 is shown in FIG. 4. Whereas adjacent storage
places 42, 43, 44, 45 are equally spaced apart from one another in
the chain 41 of the tool magazine 36 from FIG. 2, in the case of
the tool magazine 36 from FIG. 4, two pairs of storage places 42,
43 and 44, 45 are provided, in which pairs the storage places 42
and 43 or 44 and 45 are at a smaller distance 48 from one another,
while tools which are situated in different pairs and adjacent to
one another in the chain 41, i.e. 43 and 44 and also 45 and 42 are
at a larger distance 49 from one another.
[0114] This asymmetrical arrangement of the machine magazine 36 can
be implemented in particular in the case of a chain magazine, i.e.
when two storage places 42; 43 or 44; 45, respectively, which are
in each case adjacent to one another in the chain 41, lie very
closely next to one another but are at a very much greater distance
49 from the pair 44; 45 or 42; 43, respectively, which lies
diametrically opposite in the chain 41.
[0115] The distance 48 then spans, for example, the minimum
distance which has to be between two storage places in a chain 41,
whereas the distance 49 spans the distance from the working space
29 to the background magazine 31.
[0116] If, for example, the storage place 42 is now to be displaced
into the position of the storage place 43, only a very short
displacement path and thus an extremely rapid displacement is
required, whereas very much more travel time is required in the
case where the storage place 43 has to be displaced into the
position of the storage place 44.
[0117] Against this background, bridging of the distance 48 is
utilized during the secondary time to implement extremely short
tool-change times, while bridging of the distance 49 takes place
during the main time, during which, therefore, the tool spindle 23
processes a workpiece using the chucked tool W2.
[0118] In FIG. 4, a comparable starting position to FIG. 2 is
shown, such that first the tool W2 from the tool holder 46 is
deposited into the storage place 43, as can be seen in FIG. 5a.
However, only one next tool W3 is temporarily stored in the chain
41.
[0119] Thereafter, the machine magazine 36 indexes the chain 41
onward by the distance 48, such that the situation in FIG. 5b
results, in which the empty storage place 44 is now situated in the
tool-interchange position 39, as is shown by comparison with FIG.
4.
[0120] The tool W3 to be used as the next tool has simultaneously
been moved into the tool-change position 38, such that it can now
be exchanged into the tool holder 46, as can be seen in FIG.
5c.
[0121] As soon as the state according to FIG. 5c has been achieved,
the tool spindle 23 can process the workpiece using the tool W3
while the tool W4 is now deposited into the storage place 44 in
parallel with the main time, as can be seen in FIG. 5d.
[0122] Thereafter, the tool magazine is moved again until the four
corner points of the rectangle are again occupied with storage
places. This situation is shown in FIG. 5e, where the empty storage
place 45 is in the tool-change position 38, such that said storage
place 45 can, as the next storage place, remove the tool W3 from
the tool holder 46.
[0123] The tool W4, which is to be employed as the next tool, is
situated directly adjacent thereto, i.e. at the short distance 48.
The storage place 43 having the tool W2, which is now being removed
from the machine magazine 36, is situated in the tool-interchange
position 39.
[0124] In contrast to the machine magazine 36 of FIG. 2, not four
but at most two tools are simultaneously situated in the chain 41
in the case of the machine magazine 36 of FIG. 4, which likewise
contributes towards a reduction in weight and thus to a potential
for more rapid displacement.
[0125] Nevertheless, the tool magazine 36 of FIG. 4 requires a
total of four storage places 42, 43, 44 and 45; however, a maximum
of two adjacent storage places 42, 43, 44, 45 are occupied by a
tool 25.
[0126] Here, the secondary time lies in the steps according to FIG.
5a and FIG. 5b. On account of the short displacement path across
the path 48, the secondary time is extremely short here.
[0127] A further tool magazine 36 which has only three storage
places 42, 43, and 44 is shown in FIG. 6 in an illustration like in
FIG. 2 and FIG. 4. The machine magazine 36 is equipped, for
example, with a disc 51 but may just as well be implemented in the
form of a chain.
[0128] Like FIGS. 2 and 4, FIG. 6 shows the relationship between
the machine magazine 36 and the tool spindle 43 at the tool-change
position 38 and the background magazine 31 at the tool-interchange
position 39.
[0129] In FIG. 7, tool changing in four steps, which progresses in
a similar manner as in the case of the tool magazine of FIG. 2, is
shown, except that now a maximum of always only three tools are
present in the tool magazine.
[0130] First, the tool W2 is inserted into the empty storage place
43, such that the situation of FIG. 7a results. Thereafter, the
machine magazine 36 is rotated forward by one step, such that the
situation of FIG. 7b results, in which the new tool W3 is now in
the tool-change position 38, whereas the used tool W2 is situated
in the tool-interchange position 39. The tool W4 is the next but
one tool to be used.
[0131] The tool W3 is now chucked in the tool holder 46, such that
the situation of FIG. 7c results, whereupon the tool W2 is
interchanged with the tool W5, as can be seen in FIG. 7d.
Thereafter, the situation of FIG. 6 results, except that now the
storage place 42 lies as an empty storage place in the tool-change
position 38, whereas the storage place 43 lies in the
tool-interchange position 39 and has already accommodated the new
tool W5.
[0132] Finally, it should be noted that FIGS. 2 to 7 do not show
whether or not the machine magazine 36 has to be displaced in the
direction of the arrow 37 of FIG. 1 between the tool change at the
tool-change position 38 and the tool interchange at the
tool-interchange position 39.
[0133] In the event that the machine magazine 36 does not have to
be displaced, a tool change at the tool-change position 38 and a
tool interchange at the tool-interchange position 39 can at least
in part take place simultaneously, and this can further reduce the
secondary time.
[0134] The machine magazine 36 from FIG. 4 may also be arranged
such that the storage places 42, 43 and 44, 45, which are arranged
spaced apart from one another at the small distance 48, do not lie
in the deflection corners of the chain 41 but in between, i.e. as
shown in FIG. 8.
[0135] In the starting position of FIG. 8, the tool spindle 23
having the last used tool W2 is situated in the tool-change
position 38 and the machine magazine 36 having the already
previously exchanged tool W1 is in the tool-interchange position
39.
[0136] In a first step, the tools W2 and W4 are now simultaneously
deposited into the storage places 43 and 45 of the machine magazine
36. Thereafter, the machine magazine 36 is displaced by the
distance 48, such that the storage places 42 and 44 are now
situated in the tool-change position 38 or the tool-interchange
position 39, respectively.
[0137] Then, simultaneously, the tool W3 is transferred into the
tool spindle 23 and the tool W1 into the storage place, which was
previously occupied by the tool W4 and is now empty, in the
background magazine 31.
[0138] The main time now starts, during which the tool spindle 23
processes a workpiece using the tool W3. The background magazine 31
simultaneously displaces the tool W5 into the tool-interchange
position 39.
[0139] When the tool spindle 23 now approaches the tool-change
position 38 again, the machine tool is situated in the displacement
situation according to FIG. 8 again.
[0140] In the event that the machine tool is equipped with two tool
spindles 23, 23', consequently 2 times 4 storage places are
provided in the machine magazine 36, as shown in FIG. 9.
[0141] Apart from the fact that always two tools are changed both
on the tool spindles 23, 23' and on the background magazine 31, the
tool-change methods which can be carried out with multiple-spindle
machines do not differ from the method described above.
[0142] The storage places 43, 42, 43' and 42' and the storage
places 44, 45, 44' and 45' each form a group and are spaced apart
from one another in the respective group at the same distance,
which distance corresponds to half the distance between the tool
spindles 23, 23'.
* * * * *