U.S. patent application number 12/996928 was filed with the patent office on 2011-04-14 for workpiece carrier.
Invention is credited to Stefan Esser.
Application Number | 20110083604 12/996928 |
Document ID | / |
Family ID | 40220250 |
Filed Date | 2011-04-14 |
United States Patent
Application |
20110083604 |
Kind Code |
A1 |
Esser; Stefan |
April 14, 2011 |
WORKPIECE CARRIER
Abstract
A plurality of discs arranged along a central shaft and having
holders uniformly distributed over the circumference, inclined
obliquely outwards and intended for workpieces are supported in
each case on a ring surrounding the discs. The successive rings
form an approximately cylindrical cladding which prevents undesired
coating of the discs. The cladding has groups of openings for the
holders of a disc which are uniformly distributed over the
circumference at the same height and each of which is formed by an
upper recess in the ring carrying the disc and an adjacent lower
recess of the following ring. Boundary lines between successive
rings start in each case somewhat below the narrowest points of the
webs separating adjacent openings, so that the lower recesses in
each case do not narrow towards the edge of the ring and the upper
recesses narrow at most slightly in such a way that the workpiece
carrier can be assembled from bottom to top without
difficulties.
Inventors: |
Esser; Stefan; (Aachen,
DE) |
Family ID: |
40220250 |
Appl. No.: |
12/996928 |
Filed: |
June 4, 2009 |
PCT Filed: |
June 4, 2009 |
PCT NO: |
PCT/EP2009/003998 |
371 Date: |
December 8, 2010 |
Current U.S.
Class: |
118/500 |
Current CPC
Class: |
C23C 14/505 20130101;
C23C 14/564 20130101; B05C 13/00 20130101 |
Class at
Publication: |
118/500 |
International
Class: |
B05C 13/00 20060101
B05C013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 11, 2008 |
CH |
884/08 |
Claims
1. Workpiece carrier for a coating system, comprising a base (2)
and a shaft (1) anchored or mounted therein and a plurality of
discs (7) which follow one another along the shaft (1) and are
rotatable relative to the base (2) and which in each case are
provided with a plurality of holders (8) distributed over the
circumference of the disc (7), inclined obliquely outwards away
from the shaft (1) and intended for a workpiece (13), characterized
in that said workpiece carrier has a cladding which surrounds the
shaft (1) and the discs (7) and leaves free groups of openings
which are distributed over the circumference and separated in each
case by webs, through which openings in each case the holders (8)
belonging to one of the discs (7) project, and which is composed of
a plurality of rings (5) which follow one another along the shaft
(1) and are directly adjacent to one another and which abut at
boundary lines (17) which in each case divide one of the webs
present between adjacent openings of a group.
2. Workpiece carrier according to claim 1, characterized in that at
least one boundary line (17) is formed, for example, in such a way
that the mutual rotational position of the adjacent rings (5)
inevitably corresponds to a fixed required position.
3. Workpiece carrier according to claim 2, characterized in that
the at least one boundary line (17) is at least partly
approximately V-shaped.
4. Workpiece carrier according to claim 1, characterized in that
the openings of a group are of the same size in each case, are
located at the same height and are distributed uniformly over the
circumference so that adjacent openings are offset relative to one
another in each case by a fixed angular pitch.
5. Workpiece carrier according to claim 4, characterized in that
each group has the same number of openings.
6. Workpiece carrier according to claim 5, characterized in that
the openings of groups directly following one another along the
shaft (1) are offset in each case relative to one another by half
the angular pitch.
7. Workpiece carrier according to claim 5, characterized in that
the rings (5) are formed in each case so as to be invariant with
rotation through the angular pitch.
8. Workpiece carrier according to claim 1, characterized in that
the rings (5) are identical, apart from rings (5) at end
positions.
9. Workpiece carrier according to claim 1, characterized in that
the cladding has a substantially cylindrical shape.
10. Workpiece carrier according to claim 1, characterized in that
each disc (7) is supported on a ring (5).
11. Workpiece carrier according to claim 1, characterized in that
the discs (7) each surround the shaft (1) in an annular manner.
12. Workpiece carrier according to claim 1, characterized in that
the rings (5) each have, on the inside, a stop on which in each
case one of the discs (7) is supported.
13. Workpiece carrier according to claim 12, characterized in that
the stop is in the form of an all-round support ring (6).
14. Workpiece carrier according to claim 1, characterized in that
the holders (8) are each rotatably mounted on the discs (7) and a
transmission part (18) which acts on rotary stops on the holders
(8) and which in each case non-rotatably engages the shaft (1) is
provided for each disc (7).
15. Workpiece carrier according to claim 14, characterized in that
the transmission part (18) is in each case axially displaceable on
the shaft (1) and axially nondisplaceable relative to the disc (7).
Description
FIELD OF THE INVENTION
[0001] The invention relates to a workpiece carrier for a coating
system according to the precharacterizing clause of claim 1. A
workpiece carrier of this type usually carries, in corresponding
holders, a relatively large number of workpieces which are
transported past coating sources several times to ensure a coating
which is as uniform as possible.
PRIOR ART
[0002] DE 10 2004 027 989 A1 discloses a workpiece carrier of the
generic type. In particular, it has holders inclined outwards
obliquely away from the shaft, which permits a very close
arrangement of the workpieces and also leads to a generally desired
increase in the thickness of the coating towards the end face of
the workpiece and improves the uniformity of the coating especially
on end faces.
[0003] However, a disadvantage is that the discs carrying the
holders, and other parts, are inevitably also coated. This requires
regular cleaning, which must be effected very carefully in order to
avoid damage to sensitive components, with corresponding cost,
reduction of the times in use and increase of wear.
[0004] A similar workpiece carrier is disclosed in EP 1 256 637 A1.
Here, the holders are aligned parallel to a rotating central shaft
which drives the discs. Neither the discs nor the shaft nor further
parts producing in each case rotation of the holder itself are
protected from coating.
SUMMARY OF THE INVENTION
[0005] It is the object of the invention to provide a workpiece
carrier of the generic type, in which the discs carrying the
holders are protected from undesired coating. This object is
achieved by the features in the characterizing clause of claim
1.
[0006] In the workpiece carrier according to the invention, the
shaft, the discs and the lower parts of the holders are covered by
a cladding which has a very simple design and is easy to mount and
to remove and can be cleaned easily and without danger of damage.
The cladding can also serve further purposes, such as establishing
the spacing of directly successive discs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Below, the invention is explained in more detail with
reference to figures, which merely represent embodiments.
[0008] FIG. 1 schematically shows an axial longitudinal section
through a workpiece carrier according to the invention, in a first
embodiment,
[0009] FIG. 2 shows a partial side view of the workpiece carrier
according to the invention, of FIG. 1, and
[0010] FIG. 3 shows a partial exploded view of a workpiece carrier
according to the invention, in a second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] For simplification of the presentation, the workpiece
carrier according to FIG. 1, 2 is shown somewhat schematically and
is also provided with fewer holders for workpieces than will
usually be provided.
[0012] It has a central perpendicular shaft 1 of non-rotationally
symmetrical, preferably square, cross-section which is connected to
a base 2. It can be mounted on an axis coinciding with the centre
of the shaft 1 so as to be non-rotatable relative to the base 2 or
rotatable about said axis and can be driveable. A gear ring 3
mounted so as to be rotatable about said axis engages a driveable
pinion 4 and is driven by the latter in such a way that its
rotational speed differs from that of the shaft 1 so that the gear
ring 3 executes a rotational movement relative to the shaft 1.
Rings 5 of a thin rigid material, e.g. sheet metal, which in each
case are of substantially cylindrical shape and together form a
cylindrical cladding, are present non-rotatably in succession in
the axial direction on the gear ring 3. At the lower end of a ring
5, an annular support ring 6 on which an annular disc 7 surrounding
the shaft 1 is supported, likewise non-rotatably, is fastened in
each case to the inside.
[0013] Each disc 7 carries an equal number--in the example six, as
a rule preferably more--of identical holders inclined outwards
obliquely away from the shaft 1. Each of the holders 8 comprises a
bolt 9 which is anchored in an oblique bore 10 in the disc 7 and a
sleeve 11 rotatably mounted on the bolt 9 and having a bore 12 for
receiving a workpiece 13 (omitted in FIG. 2).
[0014] The holders 8 are distributed in each case uniformly over
the circumference of the disc 7 so that adjacent holders are offset
relative to one another in each case by the same angular pitch
-60.degree. in the example. The rings 5--with the exception of the
uppermost ring which is not shown--each have, at the upper edge, a
number of upper recesses 14 uniformly distributed over the
circumference, which number corresponds to the number of holders 8,
and--with the exception of the lowermost ring--likewise, at the
lower edge, uniformly distributed lower recesses 15 which however
are offset in each case by half the angular pitch relative to the
upper recesses 14 so that one of the upper recesses 14 is in each
case centred between two lower recesses 15, and vice versa.
[0015] Successive rings 5 are oriented so that the lower recesses
15 of the upper ring 5 are adjacent in each case to the upper
recesses 14 of the lower ring 5, in particular so that the edges of
the latter constitute a smooth continuation of those of the former.
The lower recess 15 and the upper recess 14 adjacent to it together
form in each case an opening in the cladding through which one of
the holders 8 projects, it also being necessary for a recess 16 to
be provided in each case at the outer edge of the support ring 6 of
the upper ring 5. The openings which belong to a group formed in
this manner between two rings are at the same height and are
distributed uniformly over the circumference of the cladding. The
openings which are preferably identical throughout may each have an
elongated elliptical shape or a similar shape, for example may be
in the form of semi-ellipses of identical or different lengths
which are connected by a rectangular central piece. The rings 5
abut one another along boundary lines 17 which are led in the
circumferential direction in such a way that they connect in each
case adjacent openings, i.e. intersect the webs separating them,
and do so in such a way that they start in the vicinity of the
narrowest point between said openings, and preferably somewhat
below said point, it being necessary to ensure that the upper
recesses 14 narrow only to such an extent that their width is at
least slightly greater even at the lower end than the diameter of
the holders 8, i.e. of their sleeves 11.
[0016] The boundary line 17 is formed so that adjacent rings 5 are
fixed in a required position with respect to their mutual angular
position, apart from rotations through a multiple of the angular
pitch. In addition, it is chosen so that said angular position
automatically adopts a fixed required position if the upper ring is
mounted so that it is rotated by less than half the angular pitch.
This is achieved in the example by virtue of the fact that the
boundary line 17 follows a preferably symmetrical V-shaped line
with a lowest point in the middle between the adjacent openings
which it connects. As a result, the web sections which separate
adjacent lower recesses 15 slide when they rest on a sleeve 11 of a
recess 8, in each case on said sleeve in such a way that the ring
is automatically rotated towards the required position.
Transversely thereto, the relative position of successive rings 5
can be controlled by stops which project, for example, on the
inside of a ring slightly above the boundary line 17 and cooperate
there with the inside of the following ring. The stops can (cf.
FIG. 3) be formed, for example, by parts of the support ring 6.
They can, however, also be absent since the effective formation of
the boundary lines 17 over the total circumference forces the ring
5 to assume the required position in each direction.
[0017] In order to produce a rotation of each holder 8 itself, a
transmission part 18 is coordinated with each of the discs 7, which
transmission part 18 is preferably a part which is punched from a
metal sheet and bent and which engages the shaft 1 in a
displaceable but non-rotatable manner, for example by having a
square recess through which said shaft projects and which is
connected to the respective disc 7 in such a way that it is
rotatable relative to said disc but is not displaceable or at most
has limited displaceability axially, parallel to the shaft 1. It
has lugs 19 which project radially outwards and engage rotary stops
on the holders 8, which rotary stops are each in the form of
notches 20 in the sleeve 11.
[0018] The workpiece carrier can be assembled by first mounting the
lowermost ring 5 on the gear ring 3, then the lowermost disc 7,
together with the corresponding transmission part 18 and the
holders 8, on the support ring 6 thereof, then the next ring 5,
etc. Owing to the position and properties of the boundary lines 17,
this does not give rise to any difficulties since the upper
recesses 14 are just wide enough even at their lower ends to be
able to receive the sleeves 11 of the holders 8, and the lower
recesses 15 each widen towards the edge. The position of the discs
7 in the direction of the shaft 1 is completely fixed in each case
by the position of the corresponding ring 5. The position of each
ring 5 in turn results from its support on the next lower ring or
on the gear ring 3. The rotational position of the rings 5 need be
checked in each case only approximately during assembly since their
relevant orientation is effected automatically by the contact with
the holders 8 of the next lower disc and finally by the V-shape of
the boundary lines 17.
[0019] FIG. 3 shows a realistic formation of a disc 7 having
eighteen holders 8 and of a ring 5 coordinated with the disc 7 and
having corresponding numbers of upper recesses 14, lower recesses
15 and recesses 16 on the support ring 6. Rotation-preventing
devices 21 which prevent rotation of the disc 7 relative to the
ring 5 when the former rests on the support ring 6 are also visible
on the same. As is evident, the webs between adjacent openings are
very narrow and the upper recesses 14 in turn are offset relative
to the lower recesses 15 by half an angular pitch. This permits an
overall very dense arrangement of the holders 8 on the workpiece
carrier. The boundary lines 17 between adjacent openings are once
again V-shaped with a lowest point in the middle.
[0020] Apart from the absence of lower recesses in the case of the
lowermost and upper recesses in the uppermost ring and any further
peculiarities of these two rings, all rings as well as all discs
are identically formed in each case so that all openings are also
identical. The rings are in each case invariant with rotation about
a multiple of the angular pitch. Each of the rings is coordinated
with one of the discs and determines the distance between said disc
and the following disc.
[0021] In this respect and also otherwise, however, substantial
deviations from the examples described are possible without
departing from the scope of the invention. Thus, the cladding and
the rings can also have a shape other than substantially
cylindrical. Moreover, the number of openings of the
groups--corresponding to the number of holders of the discs--can
vary. The shaft may consist of a plurality of sections which are
connected non-rotatably to one another and to which in each case
one transmission means can then also be firmly connected. The
workpiece carrier may also have a more complex design than
described, for example with a plurality of units having the design
described and being present on a base rotatable about an axis.
LIST OF REFERENCE SYMBOLS
[0022] 1 Shaft [0023] 2 Base [0024] 3 Gear ring [0025] 4 Pinion
[0026] 5 Ring [0027] 6 Support ring [0028] 7 Disc [0029] 8 Holder
[0030] 9 Bolt [0031] 10 Bore [0032] 11 Sleeve [0033] 12 Bore [0034]
13 Workpiece [0035] 14 Upper recess [0036] 15 Lower recess [0037]
16 Recess [0038] 17 Boundary line [0039] 18 Transmission part
[0040] 19 Lug [0041] 20 Notch [0042] 21 Rotation-preventing
device
* * * * *