U.S. patent application number 14/422592 was filed with the patent office on 2015-08-06 for vacuum pump.
This patent application is currently assigned to Oerlikon Leybold Vacum GmbH. The applicant listed for this patent is Oerlikon Leybold Vacuum Gmbh. Invention is credited to Jean-Francois Aubert.
Application Number | 20150219102 14/422592 |
Document ID | / |
Family ID | 48832920 |
Filed Date | 2015-08-06 |
United States Patent
Application |
20150219102 |
Kind Code |
A1 |
Aubert; Jean-Francois |
August 6, 2015 |
VACUUM PUMP
Abstract
A vacuum pump, particularly a rotary vane pump with a high
pumping capacity, has a pump chamber in a housing. A pump element
is arranged in the pump chamber. The pump element is supported by a
rotor shaft. The rotor shaft is connected to a belt pulley arranged
outside of the pump housing. The pump also has a motor arranged
outside of the pump housing. The drive shaft of the motor carries a
drive pulley. The drive pulley is connected to the rotor pulley via
a belt. To simplify assembly, the drive pulley and/or the rotor
pulley are formed of multiple parts.
Inventors: |
Aubert; Jean-Francois;
(Soyons, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Oerlikon Leybold Vacuum Gmbh |
Koeln |
|
DE |
|
|
Assignee: |
Oerlikon Leybold Vacum GmbH
Koeln
DE
|
Family ID: |
48832920 |
Appl. No.: |
14/422592 |
Filed: |
July 22, 2013 |
PCT Filed: |
July 22, 2013 |
PCT NO: |
PCT/EP2013/065389 |
371 Date: |
February 19, 2015 |
Current U.S.
Class: |
417/362 |
Current CPC
Class: |
F04C 25/02 20130101;
F16H 55/46 20130101; F04C 18/344 20130101; H02K 7/1004 20130101;
F04C 2230/80 20130101; H02K 7/14 20130101; H02K 15/0006 20130101;
F16H 7/24 20130101; F04C 2230/60 20130101; F04C 29/005 20130101;
F04C 2220/10 20130101; F04C 23/02 20130101 |
International
Class: |
F04C 29/00 20060101
F04C029/00; F04C 23/02 20060101 F04C023/02; F04C 25/02 20060101
F04C025/02; F04C 18/344 20060101 F04C018/344 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 25, 2012 |
DE |
202012008133.0 |
Claims
1. A vacuum pump with a high pumping capacity, comprising a pump
housing defining a pump chamber, a pumping element connected with a
rotor shaft, a belt pulley connected with the rotor shaft outside
the pump housing, and a motor arranged outside the pump housing,
the drive shaft thereof being provided with a drive pulley that is
connected with the belt pulley via a belt, wherein the drive pulley
and/or the belt pulley are of a multipart structure.
2. The vacuum pump of claim 1, wherein the drive pulley and/or the
belt pulley are of a two-part design.
3. The vacuum pump of claim 1, wherein the holding part of the
drive pulley and/or the belt pulley comprise a shaft receiving
means.
4. The vacuum pump of claim 3, wherein the drive pulley and/or the
belt pulley is connected with the drive shaft or the rotor shaft
exclusively via the shaft receiving means of the holding part.
5. The vacuum pump of claim 1, wherein the drive pulley and/or the
belt pulley comprise a connecting part with a circular
segment-shaped cross section.
6. The vacuum pump of claim 1, wherein, for connection with each
other, a connecting part and a holding part each comprise a
connecting element which form a connecting web.
7. The vacuum pump of claim 6, wherein the connecting web extends
outside the shaft receiving means and is formed in particular in a
manner corresponding to a secant of a circle.
8. The vacuum pump of claim 6, wherein the connecting elements
extend in parallel with each other and are preferably connected
with each other by means of fixing elements.
9. The vacuum pump of claim 1, wherein the belt is in the form of a
flat belt.
10. The vacuum pump of claim 1, wherein the belt is length-constant
in operation.
Description
BACKGROUND
[0001] 1. Field of the Disclosure
[0002] The disclosure relates to a vacuum pump.
[0003] 2. Discussion of the Background Art
[0004] Large vacuum pumps are driven by an external motor that is
not arranged in the pump housing. Large vacuum pumps are, in
particular, rotary vane pumps with a suction capacity of more than
200 m.sup.3/h. Likewise, the pumps may be screw-type pumps or Roots
pumps which, due to their size, are also driven by an external
motor. Such pumps comprise a pump housing defining a pump chamber.
In the pump chamber, a pumping element, such as a rotor, is
arranged and connected with a rotor shaft. With a rotary vane pump,
the pumping element is a rotor arranged eccentrically in the pump
chamber and comprising displaceable vanes arranged in slots formed
in the rotor. Outside of the pump housing, a belt pulley is
connected with the rotor shaft. Further, the vacuum pump has a
motor arranged outside the pump housing, a drive pulley being
arranged on the drive shaft of the motor. The drive pulley is
connected with the belt pulley via a belt. Since the belt becomes
stretched in operation, a tensioning element is further provided
for tensioning the belt. The tensioning element is also required
for mounting the belt pulley and the drive pulley, respectively.
If, for example, the belt pulley is already mounted and the belt is
placed on the belt pulley, the drive pulley can only be mounted if
the belt is loose. Owing to this assembly requirement, it is not
possible to use constant-length belts, i.e. belts that do not
become longer in operation.
[0005] It is an object of the disclosure to provide a vacuum pump
with a high pumping capacity, which also allows for the use of a
constant-length belt.
SUMMARY
[0006] A vacuum pump which, according to the disclosure, is a
vacuum pump with a high pumping capacity, i.e. a suction capacity
of more than 200 m.sup.3/h, comprises a pump housing defining a
pump chamber. In the pump chamber, a pumping element is arranged
and connected with a rotor shaft. For example, the pumping element
may be a rotor of a rotary vane pump, which arranged eccentrically
in the pump chamber and carries vanes. Likewise, the pumping
element may be a rotor of a screw-type pump. The rotor shaft is
driven by an external motor arranged outside the pump housing. For
this purpose, a drive pulley is connected with the drive shaft of
the motor and a belt pulley is connected with the rotor shaft, the
belt pulley being arranged outside the pump housing. A belt is
provided for power transmission, the belt being connected with the
drive pulley and the belt pulley. According to the disclosure, the
drive pulley or the belt pulley is of a multipart structure.
Thereby, when mounting the belt, it is possible to first mount only
a part of the drive pulley or of the rotor pulley or, respectively,
not to mount a part of the drive pulley or the rotor pulley.
Thereafter, the belt can be placed in a simple manner, since, due
to the multipart nature of the drive pulley and/or the belt pulley,
the pulley not yet fully mounted can be adjusted such that the belt
is not yet tensioned. If the drive pulley is comprised of two
parts, for example, of which one part corresponds to 100.degree.
and the other part corresponds to 260.degree. of the drive pulley,
for example, it is possible not to mount the smaller of the two
parts, for example, and to adjust the drive pulley such that the
belt extends along a section of the mounted part of the drive
pulley. Thereafter, the drive pulley is turned until the belt fully
engages the outer circumference of the part of the drive pulley
already mounted, and is tensioned thereby. In the next step, the
second part of the drive pulley can then be mounted.
[0007] If, for instance, the two pulleys are provided side by side
or on the same level, and the drive pulley is arranged on the left
side, the first part of the drive pulley, e.g. the part forming
260.degree. of the circumference, is mounted such that the outer
surface of this part of the drive pulley, which in operation is in
contact with the belt, is directed downwards. When the belt has
been mounted subsequently, the same extends freely above the
already mounted part of the drive pulley and thus is slightly
sagging. Then, the drive pulley is turned clockwise until the
already mounted part of the drive pulley is located on the outer
left side with respect to the arrangement described. Thereby, the
belt is tensioned. The second part of the drive pulley can thus be
mounted, within the belt, on the right side of the already mounted
part of the drive pulley or on the side between the drive pulley
and the belt pulley.
[0008] The provision of a multipart drive pulley and/or a multipart
belt pulley, as provided by the disclosure, has the advantage that
constant-length belts can be used. These are belts that, in
operation, do not become substantially longer. This has the
essential advantage that no tensioning device must be provided.
With known vacuum pumps having a belt drive, the tensioning device
functions to keep the belt taut and to allow for a loosening of the
belt for mounting purposes.
[0009] It is another advantage of the multipart drive pulley of the
present disclosure and/or the multipart belt pulley of the present
disclosure that, independent of the power supply network which has
50 Hz or 60 Hz, for example, the same motor can be used for the
pump. This is possible due to the fact that a constant pump speed
is achieved by correspondingly adapting the diameter of the drive
pulley or the belt pulley. This may well be possible also with
known pumps; however, a changeover, for example, is extremely
complex. With vacuum pumps according to the disclosure, a
changeover merely requires a replacement of the divided pulley and
the provision of a belt of corresponding length. This is
advantageous, in particular during manufacture, in that it has to
be decided only just before the final assembly, whether the pump is
used with a power supply network of 50 Hz or 60 Hz. If both the
drive pulley and the belt pulley are changed, the diameters can be
matched such that it is possible to always use the same belts.
[0010] In a particularly preferred embodiment the drive pulley
and/or the belt pulley are of a two-part structure. This has the
advantage that the assembly is simplified when compared to
single-part or multipart pulleys.
[0011] Preferably, the divided pulley comprises a holding part that
includes a shaft receiving means. The connection between the
divided pulley and the corresponding shaft is thus effected in
particular exclusively via this shaft receiving means. Accordingly,
the connection between the pulley and the shaft is realized by
means of the holding part. The part or the further parts of the
corresponding pulley are then merely connected with the holding
part and no longer serve to fix the pulley on the shaft. This
facilitates the assembly further, since a secure connection with
the shaft is already made after the holding part is mounted on the
shaft.
[0012] Further, in another preferred embodiment, the divided
pulley, i.e. the drive pulley or the rotor pulley, comprises a
connecting part with a circular segment-shaped cross section. This
connecting part is connected in particular with the holding part so
that, in a particularly preferred embodiment, a two-part pulley is
formed that comprises a holding part and a connecting part.
[0013] A connecting part which preferably has a circular
segment-shaped cross section, but which may have a different cross
section, and the holding part, which preferably comprises the shaft
receiving means, each comprise a connecting element for their
connection with one another. The two connecting elements form a
connecting web. The same extends preferably corresponding to a
secant of a circle. Thus, the connecting web is preferably provided
outside the shaft receiving means and does not extend through the
center. For the purpose of achieving an assembly that is as simple
as possible, the two connecting elements extend in parallel with
each other. Preferably, the connection of the two connecting
elements is effected by means of fixing elements such as screws or
the like. The belt is preferably designed as a flat belt and is
length-constant in operation.
[0014] Preferably, when seen in cross section, the belts have a
plurality of beads and grooves extending in parallel with each
other and cooperating with corresponding beads and grooves in the
peripheral surfaces of the belt pulley and the drive pulley.
[0015] In a particularly preferred embodiment, the vacuum pump of
the present disclosure is a rotary vane pump with high pump
capacity, especially a single-stage rotary vane pump with a suction
capacity of more than 200 m.sup.3/h.
[0016] The disclosure will be described in more detail hereunder
with reference to a preferred embodiment and the accompanying
drawings.
[0017] In the Figures:
[0018] FIG. 1 is a schematic top plan view of a vacuum pump with
belt drive,
[0019] FIG. 2 is a schematic top plan view of a divided drive
pulley, and
[0020] FIGS. 3 and 4 are schematic front views of the belt drive in
different assembly positions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] A vacuum pump, such as a rotary vane pump, has a pump
housing 10. A pump chamber 12, illustrated in a schematic, much
simplified manner in FIG. 1, is defined in the pump housing 10. In
the pump chamber 12, a pumping element 14 is arranged which takes
the form of a rotor. The rotor 14, which is arranged eccentrically
with respect to the center line of the pump chamber, carries
radially displaceable vanes 16. Due to the vanes 16 being
displaceable in the radial direction, a plurality of chambers are
formed whose volume decreases because of the rotation of the
pumping element 14. Thereby, gas is drawn through an inlet 18 into
a large pump chamber, the gas then being compressed and expelled
through an outlet 20.
[0022] The pumping element is supported by a rotor shaft 22 and is
driven by this rotor shaft 22. The rotor shaft 22 extends outward
from the pump housing 10 and carries a belt pulley 24.
[0023] Further, a motor 26 is provided that is arranged outside the
housing 10, the drive shaft 28 of the motor carrying a drive pulley
30. The rotary movement is transmitted from the drive pulley 30 to
the belt pulley 24 by means of a belt 32.
[0024] According to the disclosure, the drive pulley 30 and/or the
belt pulley 24 are of a multipart structure. FIG. 2 shows a
two-part pulley which, for example, is a drive pulley 30. The drive
pulley 30 is of a two-part design and is composed of a holding part
34 and a connecting part 36 with a circular segment-shaped cross
section, seen in top plan view.
[0025] It is a particularly preferred aspect of the disclosure that
the connection between the holding part and the corresponding
associated shaft 22 or 28 is realized via a shaft receiving means
38 that is fully integrated in the holding part. The connection
between the pulley, i.e. the drive pulley 30 in the embodiment
illustrated, and the corresponding shaft is realized exclusively
through the shaft receiving means 38 integrated in the holding part
34. The shaft receiving means 38 is connected with a partial
circumference ring 42 through substantially radially extending webs
40. Further, the holding part 34 comprises a connecting element 44
in the form of a secant of a circle. The same is arranged such that
it is located outside the shaft receiving means 34. In other words:
the shaft receiving means 34 is arranged inside the partial ring 42
as well as inside the connecting element 44.
[0026] In top plan view, the connecting part 36 has a circular
segment-shaped cross section. The connecting part 42 also comprises
a partial circumference ring 46. The same is connected with a
connecting element 48. Corresponding to the connecting element 44,
the connecting element 48 is designed as a secant of a circle. The
two connecting elements 44, 48 form a connecting web. Since, in the
embodiment illustrated, the connecting elements 44, 48 are formed
in parallel with each other, they can be connected with each other
in a simple manner using bores 50 and 52, possibly with threads,
and fixing elements, such as screws, not illustrated herein.
[0027] Referring to FIGS. 3 and 4, a description will be made
hereunder of the assembly according to the disclosure, which no
longer requires the provision of a tensioning device due to the
multipart design of the drive pulley 30 and/or the belt pulley
24.
[0028] For assembly, for example, a single-part belt pulley 24 can
be mounted on the rotor shaft 22 in a first step (FIG. 3). In the
next step the holding part 34 of the drive pulley 30 is mounted on
the drive shaft 28. Thereafter, the belt 32 can be installed. Due
to the arrangement of the holding part 34, the belt sags and can be
placed in a simple manner. Possibly existing beads extending in the
longitudinal direction of the belt 32 and corresponding recesses in
the pulleys 24, 30 do not interfere with the assembly.
[0029] In the next step the holding part 34 is turned to the
position illustrated in FIG. 4. In doing so, the belt 32 is
automatically tensioned. No tensioning device is required for this
purpose. Thereafter, the connecting part 36 can be mounted in a
simple manner from inside, i.e. in a position inside the belt 32,
so that the drive pulley 30 is mounted.
[0030] By means of corresponding assembly steps and changing one or
both pulleys 30, 34, an adaptation to different power supply
networks can be made, for example.
* * * * *