CA2545977A1 - Noise-reduced vacuum appliance - Google Patents
Noise-reduced vacuum appliance Download PDFInfo
- Publication number
- CA2545977A1 CA2545977A1 CA002545977A CA2545977A CA2545977A1 CA 2545977 A1 CA2545977 A1 CA 2545977A1 CA 002545977 A CA002545977 A CA 002545977A CA 2545977 A CA2545977 A CA 2545977A CA 2545977 A1 CA2545977 A1 CA 2545977A1
- Authority
- CA
- Canada
- Prior art keywords
- air flow
- noise
- motor
- vacuum appliance
- vacuum
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000001816 cooling Methods 0.000 claims description 12
- 238000007664 blowing Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
- A47L7/00—Suction cleaners adapted for additional purposes; Tables with suction openings for cleaning purposes; Containers for cleaning articles by suction; Suction cleaners adapted to cleaning of brushes; Suction cleaners adapted to taking-up liquids
- A47L7/0004—Suction cleaners adapted to take up liquids, e.g. wet or dry vacuum cleaners
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
- A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
- A47L9/0081—Means for exhaust-air diffusion; Means for sound or vibration damping
Abstract
A vacuum appliance includes a motor having a rotatable shaft. An air flow generating member is connected to the shaft. The air flow generated by the rotating member generates noise having a frequency and corresponding wavelength. An air flow path receives air generated by the rotating member. The air flow path has first and second channels, the lengths of which define a predetermined difference therebetween to cancel the noise. In certain embodiments, the difference is corresponds to one-half wavelength.
Description
FILE:021840.382UP
NOISE-REDUCED VACUUM APPLIANCE
BACKGROUND
The present invention relates generally to vacuum appliances.
s Vacuum appliances are well known. For example, vacuum appliances that are capable of picking up both wet and dry material, commonly referred to as wet/dry vacuums or wet/dry vacs, are often used in workshops and other environments where both wet and dry debris can accumulate. Wet/dry vacuums conventionally consist of a collection canister or drum, usually mounted on a dolly having wheels or casters, and a ~o powerhead within which a motor and impeller assembly is mounted. The motor and impeller assembly creates a suction within the drum, such that debris and/or liquid are drawn into the drum through an air inlet to which a flexible hose can be attached. A filter within the drum prevents incoming debris from escaping from the drum while allowing filtered air to escape.
~s A typical wet/dry vacuum motor and blower assembly includes a motor having a closed-face, multiple-blade blower wheel or impeller disposed on a drive shaft thereof.
The motor and blower assembly is typically disposed in a collection canister lid assembly, with the rotating blower wheel disposed within a blower chamber, sometimes referred to as a collector chamber. The collector chamber is accessed via an air intake, such that a Zo suction created by rotation of the impeller within the collector chamber causes air to be drawn into the air intake.
FILE:021840.382UP
A conventional wet/dry vacuum has two air flow systems. A first air flow system is established for cooling the motor. The second air flow system is the blower wheel or impeller airflow, which affects the suction performance of the vacuum (and the blowing performance, for those vacs which are adaptable or convertible between and vacuum and s a blower).
A common problem with vacuum cleaners, and especially wet/dry vacuums, is the excessive and irritating noise generated by the vacuum cleaner. The vacuum motor itself generates noise, and in vacuum cleaners having blowing ports, the high-velocity air exiting the blowing port further creates an especially annoying high-pitched "whine."
~o While providing a muffler device on the blowing port and/or adding noise muffling materials inside the appliance is effective at reducing some noise, other components of the appliance continue to contribute to noise production.
The present application addresses shortcomings associated with the prior art.
SUMMARY
~ s In accordance with certain teachings of the present disclosure, a vacuum appliance such as a wet dry vacuum includes a motor having a rotatable shaft. An air flow generating member, such as a blower wheel and/or cooling fan, is connected to the shaft.
The air flow generated by the rotating member generates noise having a frequency and corresponding wavelength. In motors having a commutator, such as a universal motor, Zo the rotating commutator further generates air flow and corresponding noise.
An air flow path receives air generated by the rotating member. The air flow path has first and second FILE:021840.382UP
channels, the lengths of which define a predetermined difference therebetween to cancel the noise. In certain embodiments, the difference is corresponds to one-half wavelength.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading s the following detailed description and upon reference to the drawings in which:
Figure 1 is a block diagram conceptually illustrating portions of a vacuum appliance in accordance with certain teachings of the present disclosure.
Figures 2A-2D are graphs illustrating passive noise cancellation effectiveness.
While the invention is susceptible to various modifications and alternative forms, ~o specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined ~s by the appended claims.
DETAILED DESCRIPTION
Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, zo numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, FILE:021840.382UP
which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the beneft of this disclosure.
s Figure 1 is a block diagram conceptually illustrating portions of a vacuum appliance 100 in accordance with certain teachings of the present disclosure.
The vacuum 100 includes a collection canister or drum 110 and a powerhead 112 within which a motor and impeller assembly is mounted. The powerhead I 12 creates a suction within the drum 110, such that debris and/or liquid are drawn into the drum 110 through to an air inlet 114 to which a flexible hose can be attached. A filter 120 within the drum prevents incoming debris from escaping from the drum I 10 while allowing filtered air to escape through an air exhaust port (not shown).
The powerhead 112 includes a motor 130 having a blower wheel or impeller 132 disposed on a drive shaft thereof, with the rotating blower wheel disposed within a is blower chamber 134, sometimes referred to as a collector chamber. The motor includes a cooling fan 136. A universal motor is used in exemplary vacuum systems.
The appliance 100 has two air flow systems. One is established for cooling the motor 130 with the cooling fan 136, and the other is the blower wheel 132 or impeller airflow which generates the suction inside the drum 110.
zo As noted in the background section herein, it is desirable to continue to reduce noise generated by vacuum appliances such as wet/dry vacuums. Sources of noise generated by the powerhead include the blower wheel 132, the motor's commutator/brush FILE:021840.382UP
interface, and the cooling fan 136. By manipulating passageways for the motor cooling air and the motor exhaust air such that the length of the passageway corresponds to wavelengths of noise frequencies to be eliminated, the overall noise level of the appliance is reduced without the addition of noise-reducing hardware. The passageways are created s so that the wavelengths are 180 degrees out of phase for the particular frequency to be eliminated.
In one exemplary implementation, dual air channels were provided in a wet/dry vacuum for each of three noise sources, with corresponding frequency (cycles/second) and wavelength (inches):
~o Blower wheel: 2,333,3 cycles/sec; 5.80 inches Cooling Fan: 3,666,7 cycles/sec; 3.69 inches Commutator: 7,333.3 cycles/sec; 1.85 inches.
The channels of the dual air channels corresponding to each of these noise sources is one-half wavelength different in length, so one channel "cancels" the noise of the other i s channel.
Figures 2A-2D are graphs illustrating motor frequency, frequency with commutator cancellation, frequency with cooling fan cancellation and frequency with both commutator and cooling fan cancellation, respectively. As shown in the graphs, substantial noise reduction is achieved with both commutator and cooling fan Zo cancellation.
FILE:021840.382UP
In tests where the difference between the two flow length paths for the various air channels was varied, the noise level was minimal when the difference between flow length channels was one-half wavelength. In contrast, the noise level was maximum when the difference between the flow length channels was one-quarter wavelength, s because at this difference, the noise is additive and not canceling.
The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described io in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Accordingly, the protection sought herein is as set forth in the claims below.
NOISE-REDUCED VACUUM APPLIANCE
BACKGROUND
The present invention relates generally to vacuum appliances.
s Vacuum appliances are well known. For example, vacuum appliances that are capable of picking up both wet and dry material, commonly referred to as wet/dry vacuums or wet/dry vacs, are often used in workshops and other environments where both wet and dry debris can accumulate. Wet/dry vacuums conventionally consist of a collection canister or drum, usually mounted on a dolly having wheels or casters, and a ~o powerhead within which a motor and impeller assembly is mounted. The motor and impeller assembly creates a suction within the drum, such that debris and/or liquid are drawn into the drum through an air inlet to which a flexible hose can be attached. A filter within the drum prevents incoming debris from escaping from the drum while allowing filtered air to escape.
~s A typical wet/dry vacuum motor and blower assembly includes a motor having a closed-face, multiple-blade blower wheel or impeller disposed on a drive shaft thereof.
The motor and blower assembly is typically disposed in a collection canister lid assembly, with the rotating blower wheel disposed within a blower chamber, sometimes referred to as a collector chamber. The collector chamber is accessed via an air intake, such that a Zo suction created by rotation of the impeller within the collector chamber causes air to be drawn into the air intake.
FILE:021840.382UP
A conventional wet/dry vacuum has two air flow systems. A first air flow system is established for cooling the motor. The second air flow system is the blower wheel or impeller airflow, which affects the suction performance of the vacuum (and the blowing performance, for those vacs which are adaptable or convertible between and vacuum and s a blower).
A common problem with vacuum cleaners, and especially wet/dry vacuums, is the excessive and irritating noise generated by the vacuum cleaner. The vacuum motor itself generates noise, and in vacuum cleaners having blowing ports, the high-velocity air exiting the blowing port further creates an especially annoying high-pitched "whine."
~o While providing a muffler device on the blowing port and/or adding noise muffling materials inside the appliance is effective at reducing some noise, other components of the appliance continue to contribute to noise production.
The present application addresses shortcomings associated with the prior art.
SUMMARY
~ s In accordance with certain teachings of the present disclosure, a vacuum appliance such as a wet dry vacuum includes a motor having a rotatable shaft. An air flow generating member, such as a blower wheel and/or cooling fan, is connected to the shaft.
The air flow generated by the rotating member generates noise having a frequency and corresponding wavelength. In motors having a commutator, such as a universal motor, Zo the rotating commutator further generates air flow and corresponding noise.
An air flow path receives air generated by the rotating member. The air flow path has first and second FILE:021840.382UP
channels, the lengths of which define a predetermined difference therebetween to cancel the noise. In certain embodiments, the difference is corresponds to one-half wavelength.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading s the following detailed description and upon reference to the drawings in which:
Figure 1 is a block diagram conceptually illustrating portions of a vacuum appliance in accordance with certain teachings of the present disclosure.
Figures 2A-2D are graphs illustrating passive noise cancellation effectiveness.
While the invention is susceptible to various modifications and alternative forms, ~o specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined ~s by the appended claims.
DETAILED DESCRIPTION
Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, zo numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, FILE:021840.382UP
which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the beneft of this disclosure.
s Figure 1 is a block diagram conceptually illustrating portions of a vacuum appliance 100 in accordance with certain teachings of the present disclosure.
The vacuum 100 includes a collection canister or drum 110 and a powerhead 112 within which a motor and impeller assembly is mounted. The powerhead I 12 creates a suction within the drum 110, such that debris and/or liquid are drawn into the drum 110 through to an air inlet 114 to which a flexible hose can be attached. A filter 120 within the drum prevents incoming debris from escaping from the drum I 10 while allowing filtered air to escape through an air exhaust port (not shown).
The powerhead 112 includes a motor 130 having a blower wheel or impeller 132 disposed on a drive shaft thereof, with the rotating blower wheel disposed within a is blower chamber 134, sometimes referred to as a collector chamber. The motor includes a cooling fan 136. A universal motor is used in exemplary vacuum systems.
The appliance 100 has two air flow systems. One is established for cooling the motor 130 with the cooling fan 136, and the other is the blower wheel 132 or impeller airflow which generates the suction inside the drum 110.
zo As noted in the background section herein, it is desirable to continue to reduce noise generated by vacuum appliances such as wet/dry vacuums. Sources of noise generated by the powerhead include the blower wheel 132, the motor's commutator/brush FILE:021840.382UP
interface, and the cooling fan 136. By manipulating passageways for the motor cooling air and the motor exhaust air such that the length of the passageway corresponds to wavelengths of noise frequencies to be eliminated, the overall noise level of the appliance is reduced without the addition of noise-reducing hardware. The passageways are created s so that the wavelengths are 180 degrees out of phase for the particular frequency to be eliminated.
In one exemplary implementation, dual air channels were provided in a wet/dry vacuum for each of three noise sources, with corresponding frequency (cycles/second) and wavelength (inches):
~o Blower wheel: 2,333,3 cycles/sec; 5.80 inches Cooling Fan: 3,666,7 cycles/sec; 3.69 inches Commutator: 7,333.3 cycles/sec; 1.85 inches.
The channels of the dual air channels corresponding to each of these noise sources is one-half wavelength different in length, so one channel "cancels" the noise of the other i s channel.
Figures 2A-2D are graphs illustrating motor frequency, frequency with commutator cancellation, frequency with cooling fan cancellation and frequency with both commutator and cooling fan cancellation, respectively. As shown in the graphs, substantial noise reduction is achieved with both commutator and cooling fan Zo cancellation.
FILE:021840.382UP
In tests where the difference between the two flow length paths for the various air channels was varied, the noise level was minimal when the difference between flow length channels was one-half wavelength. In contrast, the noise level was maximum when the difference between the flow length channels was one-quarter wavelength, s because at this difference, the noise is additive and not canceling.
The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described io in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Accordingly, the protection sought herein is as set forth in the claims below.
Claims (5)
1. A vacuum appliance, comprising:
a motor having a rotatable shaft;
an air flow generating member connected to the shaft, the air flow generating member further generating noise having a frequency and corresponding wavelength; and an air flow path receiving air generated by the air flow generating member, the air flow path including first and second channels, each channel defining corresponding first and second lengths, the first and second lengths defining a predetermined difference therebetween to cancel the noise.
a motor having a rotatable shaft;
an air flow generating member connected to the shaft, the air flow generating member further generating noise having a frequency and corresponding wavelength; and an air flow path receiving air generated by the air flow generating member, the air flow path including first and second channels, each channel defining corresponding first and second lengths, the first and second lengths defining a predetermined difference therebetween to cancel the noise.
2. The vacuum appliance of claim 1, wherein the predetermined difference between the first and second lengths corresponds to one-half wavelength.
3. The vacuum appliance of claim 1, wherein the air flow generating member comprises a blower wheel.
4. The vacuum appliance of claim 1, wherein the air flow generating member comprises a cooling fan.
5. The vacuum appliance of claim 1, wherein the air flow generating member comprises a commutator of the motor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US59481205P | 2005-05-09 | 2005-05-09 | |
| US60/594,812 | 2005-05-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2545977A1 true CA2545977A1 (en) | 2006-11-09 |
Family
ID=37441480
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002545977A Abandoned CA2545977A1 (en) | 2005-05-09 | 2006-05-08 | Noise-reduced vacuum appliance |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US20060260866A1 (en) |
| CA (1) | CA2545977A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10869586B2 (en) | 2016-11-17 | 2020-12-22 | Karcher North America, Inc. | Portable vacuum and related accessories |
Family Cites Families (35)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4120616A (en) * | 1975-10-06 | 1978-10-17 | Breuer Electric Manufacturing Company | Vacuum cleaner-blower assembly with sound absorbing arrangement |
| US4015683A (en) * | 1975-12-29 | 1977-04-05 | Purex Corporation Ltd. | Noise suppressor for vacuum sweeper and the like |
| US4162904A (en) * | 1978-04-10 | 1979-07-31 | American Air Filter Company, Inc. | Silencer-separator device |
| DE2944749A1 (en) * | 1979-11-06 | 1981-05-14 | Rommag P. Wörwag & Co., Romanshorn | VACUUM CLEANER |
| US4418443A (en) * | 1981-12-07 | 1983-12-06 | Breuer Electric Mfg. Co. | Noise suppressor for vacuum sweepers and the like |
| DE3225258C2 (en) * | 1982-07-06 | 1985-11-28 | Guido Oberdorfer Wap-Maschinen, 7919 Bellenberg | Vacuum cleaner |
| US4435877A (en) * | 1982-09-30 | 1984-03-13 | Shop-Vac Corporation | Noise reducing means for vacuum cleaner |
| US4824333A (en) * | 1985-10-01 | 1989-04-25 | Rexair, Inc. | Air blower assembly for vacuum cleaners |
| JPH01305916A (en) * | 1988-06-06 | 1989-12-11 | Hitachi Ltd | Electric cleaner |
| US4938309A (en) * | 1989-06-08 | 1990-07-03 | M.D. Manufacturing, Inc. | Built-in vacuum cleaning system with improved acoustic damping design |
| US4970753A (en) * | 1990-02-23 | 1990-11-20 | Ryobi Motor Products Corp. | Vacuum cleaner noise reducing arrangement |
| US5067584A (en) * | 1990-04-25 | 1991-11-26 | Williams William H | Low cost replaceable type sound dampening unit for vacuum cleaning machine |
| US5129793A (en) * | 1990-10-24 | 1992-07-14 | Copeland Corporation | Suction muffler |
| JP2574573B2 (en) * | 1991-10-18 | 1997-01-22 | 松下精工株式会社 | Ventilation fan |
| US5502869A (en) * | 1993-02-09 | 1996-04-02 | Noise Cancellation Technologies, Inc. | High volume, high performance, ultra quiet vacuum cleaner |
| AU707268B2 (en) * | 1995-10-10 | 1999-07-08 | Nilfisk A/S | A silencer for a suction cleaner |
| TW381150B (en) * | 1996-03-29 | 2000-02-01 | Sanyo Electric Co | Electric fan |
| US5957664A (en) * | 1996-11-08 | 1999-09-28 | Air Products And Chemicals, Inc. | Gas pulsation dampener for positive displacement blowers and compressors |
| US6014791A (en) * | 1998-02-09 | 2000-01-18 | Soundesign, L.L.C. | Quiet vacuum cleaner using a vacuum pump with a lobed chamber |
| US5979013A (en) * | 1998-03-10 | 1999-11-09 | The Toro Company | Portable blower with noise reduction |
| US6035485A (en) * | 1998-03-20 | 2000-03-14 | Emerson Electric Co. | Vacuum cleaner muffler/deflector |
| AUPP712998A0 (en) * | 1998-11-16 | 1998-12-10 | Field, Christopher David | Noise attenuation device |
| US6385809B1 (en) * | 2000-03-03 | 2002-05-14 | Emerson Electric Co. | Gasketless wet/dry vacuum with switchable blowing |
| US6325844B1 (en) * | 2000-05-31 | 2001-12-04 | Florida Pneumatic Manufacturing Corporation | Filter and muffler device for vacuum mechanism |
| EP1172059A1 (en) * | 2000-07-14 | 2002-01-16 | Nilfisk Advance A/S | A suction apparatus with noise reduction means |
| CA2332195A1 (en) * | 2001-01-24 | 2002-07-24 | Alexandre Plomteux | Quiet central vacuum power unit |
| US6499182B2 (en) * | 2001-05-29 | 2002-12-31 | Shop-Vac Corporation | Convertible blower port for vacuum cleaner |
| US6804857B1 (en) * | 2001-09-20 | 2004-10-19 | M.D. Manufacturing, Inc. | Apparatus for dampening the noise of a vacuum cleaner |
| US20030234137A1 (en) * | 2002-06-25 | 2003-12-25 | Buckner Don Martin | Vacuum pump filter silencer combination |
| CN1279868C (en) * | 2003-08-26 | 2006-10-18 | 苏州金莱克清洁器具有限公司 | Dust-collector noise silencer |
| EP1748716A4 (en) * | 2004-05-03 | 2009-08-26 | Charles A Castronovo | Vacuum cleaners especially quiet vacuum cleaners, pumps, and engines |
| US7434657B2 (en) * | 2004-05-11 | 2008-10-14 | H-P Products, Inc. | Acoustic foam sound reducer for vacuum power unit |
| US7627928B2 (en) * | 2005-02-17 | 2009-12-08 | Shop-Vac Corporation | Removable internal air diffuser |
| US7819223B2 (en) * | 2006-04-03 | 2010-10-26 | Praxair Technology, Inc. | Silencer for adsorption-based gas separation systems |
| US7247180B1 (en) * | 2006-04-28 | 2007-07-24 | Oneida Air Systems, Inc. | Silencer for dust collection system |
-
2006
- 2006-05-08 CA CA002545977A patent/CA2545977A1/en not_active Abandoned
- 2006-05-09 US US11/382,466 patent/US20060260866A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| US20060260866A1 (en) | 2006-11-23 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |