CA1297148C - High frequency signal suppression component - Google Patents
High frequency signal suppression componentInfo
- Publication number
- CA1297148C CA1297148C CA000540598A CA540598A CA1297148C CA 1297148 C CA1297148 C CA 1297148C CA 000540598 A CA000540598 A CA 000540598A CA 540598 A CA540598 A CA 540598A CA 1297148 C CA1297148 C CA 1297148C
- Authority
- CA
- Canada
- Prior art keywords
- conductor
- elastic material
- component
- passage
- high frequency
- 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.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
- H04N3/10—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical
- H04N3/16—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical by deflecting electron beam in cathode-ray tube, e.g. scanning corrections
- H04N3/18—Generation of supply voltages, in combination with electron beam deflecting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/02—Casings
- H01F27/027—Casings specially adapted for combination of signal type inductors or transformers with electronic circuits, e.g. mounting on printed circuit boards
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
- H04N3/10—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical
- H04N3/16—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical by deflecting electron beam in cathode-ray tube, e.g. scanning corrections
Abstract
RCA 83,439 ABSTRACT OF THE DISCLOSURE
A signal suppression component such as a ferrite shield bead includes a cylindrical magnetically permeable member that has a longitudinal passage formed through it.
The passage is filled with an elastic silicone rubber material. When the component is placed on a conductor or component lead, the elastic material forms a damping layer between the conductor and the permeable member to prevent audible vibration of the element due to current flow in the conductor. Such a component is especially useful in a line rate deflection circuit and in a resonant retrace power supply circuit.
A signal suppression component such as a ferrite shield bead includes a cylindrical magnetically permeable member that has a longitudinal passage formed through it.
The passage is filled with an elastic silicone rubber material. When the component is placed on a conductor or component lead, the elastic material forms a damping layer between the conductor and the permeable member to prevent audible vibration of the element due to current flow in the conductor. Such a component is especially useful in a line rate deflection circuit and in a resonant retrace power supply circuit.
Description
-1- RCA 83,~39 HIGH FREQUENCY SIGNAL SUPPRESSION COMPO~ENT
This invention relates to high frequency signal suppression components for use in video display apparatus.
Video display appara-tus, such as television receivers or computer monitors, may incorporate circuitry that either generates or is susceptible to high frequency interference signals. In order to attenuate the propagation of these high frequency siynals, or reduce the amount of high frequency energy that reaches particularly sensitive circuitry, signal suppression components may be placed along the conductor paths or component leads leading to or exiting from the circuits or components that are desired to be isolated. These components, which may be of a tubular form, are manufactured of a material, such as nickel-zinc ferrite, or a similar soft ferrite material, that act as high frequency chokes and attenuate high frequency current flowing in the circuit or component conductors. These shield beads, also referred to as ferrite beads, are placed over appropriate circuit or component leads. The size of the bead and type of material from which the bead is formed are selected based on the signal attenuation characteristics desired. These characteristics are supplied by the manufacturers of the shield or ferrite beads, such as Fair-Rite Products Corp., for example.
The horizontal deflection output circuit and the horizontal deflection flyback pulse-derived power supplies comprise circuits where the previously described ferrite beads may be required. The horizontal output circuit, for example, incorporates fast switching diodes that generate spurious high frequency signals. The horizontal or line rate signal, of the order of 15.75 kHz, for example, associated with these circuits, may cause the ferrite beads to vibrate against the mounting circuit board or against components or conductors, producing audible tones that may be distracting or unpleasant to the video display apparatus user. Gluing each of the ferrite beads in place to prevent ~7~
This invention relates to high frequency signal suppression components for use in video display apparatus.
Video display appara-tus, such as television receivers or computer monitors, may incorporate circuitry that either generates or is susceptible to high frequency interference signals. In order to attenuate the propagation of these high frequency siynals, or reduce the amount of high frequency energy that reaches particularly sensitive circuitry, signal suppression components may be placed along the conductor paths or component leads leading to or exiting from the circuits or components that are desired to be isolated. These components, which may be of a tubular form, are manufactured of a material, such as nickel-zinc ferrite, or a similar soft ferrite material, that act as high frequency chokes and attenuate high frequency current flowing in the circuit or component conductors. These shield beads, also referred to as ferrite beads, are placed over appropriate circuit or component leads. The size of the bead and type of material from which the bead is formed are selected based on the signal attenuation characteristics desired. These characteristics are supplied by the manufacturers of the shield or ferrite beads, such as Fair-Rite Products Corp., for example.
The horizontal deflection output circuit and the horizontal deflection flyback pulse-derived power supplies comprise circuits where the previously described ferrite beads may be required. The horizontal output circuit, for example, incorporates fast switching diodes that generate spurious high frequency signals. The horizontal or line rate signal, of the order of 15.75 kHz, for example, associated with these circuits, may cause the ferrite beads to vibrate against the mounting circuit board or against components or conductors, producing audible tones that may be distracting or unpleasant to the video display apparatus user. Gluing each of the ferrite beads in place to prevent ~7~
-2- RCA 83,439 vibration is time consuming, and consequently increases the cost of the video display apparatus.
In accordance with an aspect of the present invention, a high frequency signal suppression component comprises a magnetically permeable member having a passage formed through it. An elastic material, located within the passage, permits an electrical conductor to be inserted through the passage and forms an elastic layer between the conductor and the member.
In the accompanying drawing:
FIGURE 1 iS a block and schematic diagram of a portion of a video display apparatus, illustrating an aspect of the present invention;
FIGURE 2 is an isometric view of a high frequency signal suppression component in accordance with an aspect of the present invention;
FIGURE 3 is a cross-sectional plan view of the signal suppression component shown in FIGURE 2; and FIGURE 4 is a cross-sectional plan view of the component shown in FIGURE 2, illustrating an aspect of'its operation.
FIGURE 1 illustrates a portion of a video display apparatus including a horizontal or line rate deflection circuit 10 and a power supply circuit 11. Horizontal deflection circuit 10, which may be of a conventional resonant retrace-type, includes horizontal driver circuitry 12 that receives horizontal or line rate synchronizing pulses from a source of synchronizing signals (not shown) via a terminal 13. Horizontal driver circuitry 12 generates switching pulses which are applied to the base of a horizontal output transistor 14 via a transformer 15.
The collector of output transistor 14 is coupled via a high frequency signal suppression component 16, such as a ferrite shield bead, to the cathode of a damper diode 17, one terminal of a retrace capacitor 20, and one terminal of a deflection winding 21. The other terminal of deflection ~t^*~
~3- RCA 83,~39 winding 21 is coupled via an S-shaping capacitor 22 to ground. The emitter of ou-tput transistor 14, the anode of diode 17, and the oth~r terminal of capacitor 20 are also coupled to ground. output transistor 14 produces horizontal deflection current in deflection winding 21 that generates an electromagnetic field in order to deflect the electron beams produced by a cathode ray tube (not shown).
Signal suppression component 16 is present to attenuate the high frequency spurious signals generated by the switching of damper diode 17.
Power is applied to output transistor 14 from a source of potential of the order of +130 volts via a primary winding 23 of a power supply transformer 24.
Flyback or resonant retrace pulses produced by the switching of output transistor 14 appear across primary winding 23. By transformer action, voltages are produced across secondary winding 25 and high voltage winding 26.
High voltage winding 26 produces the high voltage or ultor potential for the cathode ray tube (not shown) at a terminal designated ~HV. The current produced by the voltage developed across secondary winding 25 is rectified by a diode 27 via a signal suppression component 30, such as a ferrite bead, and charges a capacitor 31 via a similar signal suppression component 32 in order to produce a load circuit supply voltage at a terminal designa-ted +V.
In FIGURE 1, this voltage is illustratively used to power horizontal driver circuitry 12. Signal suppression components 30 and 32 act to attenuate high frequency spurious signals produced by alternating current flow in diode 27, for example.
In accordance with a novel aspect of the present invention, signal suppression components 16, 30, and 32 are representatively shown as component 38 in FIGURES 2, 3, and 4. Component 38 comprises a magnetically permeable member 33, illustratively shown as having a cylindrical form in FIGURES 2 and 3. Signal suppression components having noncircular cross-sections are of course possible. Member 33 is illustratively manufactured of a soft ferrite -4- RC~ 83,~39 material, such as nickel-zinc ferri~e, magnesium-zinc ferrite, or manganese-zinc ferrite, for example. Member 33 has a longitudinal passage 34 formed -through it that defines an inner wall 35 of member 33. Passage 3~ is filled with a plug of an elastic material 36, illustratively comprising a silicone rubber compound manufactured, for example, by Dow Corning Corporation in a variety of formulations under the trade name Sylgard. The desired characteristics of elastic material 36 are such that a conductor or wire 37, shown in FIGURE 4, such as the conductor between the collector of output transistor 14 and diode 17, may be inserted through elastic material 36 and consequently through passage 34 without distorting or bending conductor 37. The diameter of passage 34 is chosen such that elastic material 36 forms a resiliant layer or eushion 40 between the inner wall 35 of member 33 and conductor 37. Layer 40 acts as a damping or attenuating agent to substantially prevent the vibration of component 38 on conductor 37, and therefore substantially eliminates any generation of audible signals when horizontal or line rate current is flowing in conductor 37. Component 38 therefore eliminates the need to glue or otherwise restrain the movement of signal suppression components in order to prevent audible vibration. The viscosity of elastic material 36 may be selected to produce optimum vibration attenuation based on the particular application and location of the signal suppression component 38. For example, the use of the eombination Dow Corning Sylgard 527 and Sylgard 567 in various ratios produces a wide range of material viscosities. It is therefore possible to select a particular compound ratio that will result in optimum signal attenuation for a particular applieation or location of suppression component 38.
In aecordance with another novel aspect of the present invention, the adhesion between elastic material 36 and conduetor 37 is sufficient to hold component 38 in place on conductor 37 during assembly of the video display apparatus without the need for additional attachment means.
~7~
-5- RCA 83,439 This greatly simplifies assembly as it eliminates the need for manually maintaining signal suppression components in place on -their respective conductors or electrical component leads, for example, until -those conductors or 5 - electrical componen-ts are inserted into a circuit board.
Component 38 may be formed, for example, by dipping member 33 in a con-tainer of the desired elastic material 36, or by placing member 33 in elastic material 36 and then removing the excess elastic material by suction.
In either process, a plug of elastic material 36 will remain in passage 34 of member 33.
In accordance with an aspect of the present invention, a high frequency signal suppression component comprises a magnetically permeable member having a passage formed through it. An elastic material, located within the passage, permits an electrical conductor to be inserted through the passage and forms an elastic layer between the conductor and the member.
In the accompanying drawing:
FIGURE 1 iS a block and schematic diagram of a portion of a video display apparatus, illustrating an aspect of the present invention;
FIGURE 2 is an isometric view of a high frequency signal suppression component in accordance with an aspect of the present invention;
FIGURE 3 is a cross-sectional plan view of the signal suppression component shown in FIGURE 2; and FIGURE 4 is a cross-sectional plan view of the component shown in FIGURE 2, illustrating an aspect of'its operation.
FIGURE 1 illustrates a portion of a video display apparatus including a horizontal or line rate deflection circuit 10 and a power supply circuit 11. Horizontal deflection circuit 10, which may be of a conventional resonant retrace-type, includes horizontal driver circuitry 12 that receives horizontal or line rate synchronizing pulses from a source of synchronizing signals (not shown) via a terminal 13. Horizontal driver circuitry 12 generates switching pulses which are applied to the base of a horizontal output transistor 14 via a transformer 15.
The collector of output transistor 14 is coupled via a high frequency signal suppression component 16, such as a ferrite shield bead, to the cathode of a damper diode 17, one terminal of a retrace capacitor 20, and one terminal of a deflection winding 21. The other terminal of deflection ~t^*~
~3- RCA 83,~39 winding 21 is coupled via an S-shaping capacitor 22 to ground. The emitter of ou-tput transistor 14, the anode of diode 17, and the oth~r terminal of capacitor 20 are also coupled to ground. output transistor 14 produces horizontal deflection current in deflection winding 21 that generates an electromagnetic field in order to deflect the electron beams produced by a cathode ray tube (not shown).
Signal suppression component 16 is present to attenuate the high frequency spurious signals generated by the switching of damper diode 17.
Power is applied to output transistor 14 from a source of potential of the order of +130 volts via a primary winding 23 of a power supply transformer 24.
Flyback or resonant retrace pulses produced by the switching of output transistor 14 appear across primary winding 23. By transformer action, voltages are produced across secondary winding 25 and high voltage winding 26.
High voltage winding 26 produces the high voltage or ultor potential for the cathode ray tube (not shown) at a terminal designated ~HV. The current produced by the voltage developed across secondary winding 25 is rectified by a diode 27 via a signal suppression component 30, such as a ferrite bead, and charges a capacitor 31 via a similar signal suppression component 32 in order to produce a load circuit supply voltage at a terminal designa-ted +V.
In FIGURE 1, this voltage is illustratively used to power horizontal driver circuitry 12. Signal suppression components 30 and 32 act to attenuate high frequency spurious signals produced by alternating current flow in diode 27, for example.
In accordance with a novel aspect of the present invention, signal suppression components 16, 30, and 32 are representatively shown as component 38 in FIGURES 2, 3, and 4. Component 38 comprises a magnetically permeable member 33, illustratively shown as having a cylindrical form in FIGURES 2 and 3. Signal suppression components having noncircular cross-sections are of course possible. Member 33 is illustratively manufactured of a soft ferrite -4- RC~ 83,~39 material, such as nickel-zinc ferri~e, magnesium-zinc ferrite, or manganese-zinc ferrite, for example. Member 33 has a longitudinal passage 34 formed -through it that defines an inner wall 35 of member 33. Passage 3~ is filled with a plug of an elastic material 36, illustratively comprising a silicone rubber compound manufactured, for example, by Dow Corning Corporation in a variety of formulations under the trade name Sylgard. The desired characteristics of elastic material 36 are such that a conductor or wire 37, shown in FIGURE 4, such as the conductor between the collector of output transistor 14 and diode 17, may be inserted through elastic material 36 and consequently through passage 34 without distorting or bending conductor 37. The diameter of passage 34 is chosen such that elastic material 36 forms a resiliant layer or eushion 40 between the inner wall 35 of member 33 and conductor 37. Layer 40 acts as a damping or attenuating agent to substantially prevent the vibration of component 38 on conductor 37, and therefore substantially eliminates any generation of audible signals when horizontal or line rate current is flowing in conductor 37. Component 38 therefore eliminates the need to glue or otherwise restrain the movement of signal suppression components in order to prevent audible vibration. The viscosity of elastic material 36 may be selected to produce optimum vibration attenuation based on the particular application and location of the signal suppression component 38. For example, the use of the eombination Dow Corning Sylgard 527 and Sylgard 567 in various ratios produces a wide range of material viscosities. It is therefore possible to select a particular compound ratio that will result in optimum signal attenuation for a particular applieation or location of suppression component 38.
In aecordance with another novel aspect of the present invention, the adhesion between elastic material 36 and conduetor 37 is sufficient to hold component 38 in place on conductor 37 during assembly of the video display apparatus without the need for additional attachment means.
~7~
-5- RCA 83,439 This greatly simplifies assembly as it eliminates the need for manually maintaining signal suppression components in place on -their respective conductors or electrical component leads, for example, until -those conductors or 5 - electrical componen-ts are inserted into a circuit board.
Component 38 may be formed, for example, by dipping member 33 in a con-tainer of the desired elastic material 36, or by placing member 33 in elastic material 36 and then removing the excess elastic material by suction.
In either process, a plug of elastic material 36 will remain in passage 34 of member 33.
Claims (9)
1. A high frequency signal suppression component comprising:
a magnetically permeable member having a longitudinal conductor-receiving passage formed therethrough, said passage defining an inner wall of said member; and an elastic material disposed within said passage, said material permitting an electrical conductor to be inserted therethrough and forming a resilient layer between said conductor and said inner wall of said member.
a magnetically permeable member having a longitudinal conductor-receiving passage formed therethrough, said passage defining an inner wall of said member; and an elastic material disposed within said passage, said material permitting an electrical conductor to be inserted therethrough and forming a resilient layer between said conductor and said inner wall of said member.
2. The component defined in Claim 1, wherein said elastic material substantially prevents the vibration of said member on said conductor when current flows in said conductor.
3. The component defined in Claim 1, wherein said elastic material adheres to said conductor for maintaining said member in place on said conductor without additional attachment means.
4. The component defined in Claim 1, wherein said elastic material comprises a silicone rubber.
5. The component defined in Claim 1, wherein the viscosity of said elastic material is chosen in accordance with the size of said member.
6. A line rate deflection circuit for a video display apparatus comprising:
an output circuit incorporating an output device providing a line rate deflection current in a conductor;
a high frequency signal suppression means located on said conductor comprising:
a magnetically permeable member having a passage formed therethrough for receiving said conductor, and -7- RCA 83,439 an elastic material disposed within said passage for forming a resilient layer between said conductor and said member.
an output circuit incorporating an output device providing a line rate deflection current in a conductor;
a high frequency signal suppression means located on said conductor comprising:
a magnetically permeable member having a passage formed therethrough for receiving said conductor, and -7- RCA 83,439 an elastic material disposed within said passage for forming a resilient layer between said conductor and said member.
7. The circuit defined in Claim 6, wherein said elastic material substantially prevents audible vibration of said member due to said line rate current flowing in said conductor.
8. The circuit defined in Claim 6, wherein said elastic material adheres to said conductor for maintaining said member in place on said conductor without additional attachment means.
9. A resonant retrace power supply circuit for a video display apparatus comprising:
a transformer incorporating a winding producing a line rate current in a conductor;
a high frequency signal suppression means located on said conductor comprising:
a magnetically permeable member having a passage formed therethrough for receiving said conductor, and an elastic material disposed within said passage for forming a resilient layer between said conductor and said member.
a transformer incorporating a winding producing a line rate current in a conductor;
a high frequency signal suppression means located on said conductor comprising:
a magnetically permeable member having a passage formed therethrough for receiving said conductor, and an elastic material disposed within said passage for forming a resilient layer between said conductor and said member.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US88022586A | 1986-06-30 | 1986-06-30 | |
| US880,225 | 1986-06-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1297148C true CA1297148C (en) | 1992-03-10 |
Family
ID=25375781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000540598A Expired - Fee Related CA1297148C (en) | 1986-06-30 | 1987-06-25 | High frequency signal suppression component |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS6327005A (en) |
| KR (1) | KR950009656B1 (en) |
| CA (1) | CA1297148C (en) |
| DE (1) | DE3721427C2 (en) |
| GB (1) | GB2193380B (en) |
| HK (1) | HK61895A (en) |
| SG (1) | SG31165G (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4958134A (en) * | 1987-09-04 | 1990-09-18 | Kabushiki Kaisha Toshiba | Noise suppression device comprising a toroid winding |
| US4818957A (en) * | 1988-03-31 | 1989-04-04 | Hewlett-Packard Company | Ferrite toroid isolator |
| JP2564779Y2 (en) * | 1992-01-17 | 1998-03-09 | ソニー株式会社 | Ferrite bead |
| DE4311126C2 (en) * | 1993-04-05 | 1998-03-12 | Siemens Matsushita Components | Current-compensated multiple choke in a compact design |
| KR101596388B1 (en) | 2015-05-18 | 2016-02-22 | (주)미광산업기계 | hermetic type conveyor apparatus |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1105018B (en) * | 1959-04-22 | 1961-04-20 | Koch & Sterzel Kommanditgesell | Process for the production of a tight connection between a cast resin insulating body and a strong bushing bolt cast in it in a high-voltage bushing |
| US3375436A (en) * | 1964-11-17 | 1968-03-26 | Rca Corp | Regulated high voltage d.c. power supply |
| US4656451A (en) * | 1986-01-23 | 1987-04-07 | Ferronics, Inc. | Electronic noise suppressor |
-
1987
- 1987-06-25 GB GB8714913A patent/GB2193380B/en not_active Expired - Fee Related
- 1987-06-25 CA CA000540598A patent/CA1297148C/en not_active Expired - Fee Related
- 1987-06-25 SG SG283/93A patent/SG31165G/en unknown
- 1987-06-29 DE DE3721427A patent/DE3721427C2/en not_active Expired - Fee Related
- 1987-06-29 JP JP62162188A patent/JPS6327005A/en active Pending
- 1987-06-29 KR KR1019870006611A patent/KR950009656B1/en not_active IP Right Cessation
-
1995
- 1995-04-27 HK HK61895A patent/HK61895A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DE3721427A1 (en) | 1988-01-07 |
| HK61895A (en) | 1995-05-05 |
| KR950009656B1 (en) | 1995-08-25 |
| DE3721427C2 (en) | 1997-02-06 |
| JPS6327005A (en) | 1988-02-04 |
| KR880001143A (en) | 1988-03-31 |
| SG31165G (en) | 1993-05-21 |
| GB2193380A (en) | 1988-02-03 |
| GB2193380B (en) | 1990-05-23 |
| GB8714913D0 (en) | 1987-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1297148C (en) | High frequency signal suppression component | |
| US4890044A (en) | High frequency signal suppression component | |
| US5357175A (en) | Deflection and high voltage circuit | |
| CA1233242A (en) | Cathode-ray tube arc-over protection for digital data in television display apparatus | |
| KR100299924B1 (en) | Video Display Deflector | |
| CA1213365A (en) | High dc voltage generator | |
| US5949665A (en) | Soft start pulse width modulation integrated circuit | |
| KR900004956B1 (en) | Power circuit for television | |
| US3912971A (en) | Television display apparatus provided with a circuit arrangement for generating a sawtooth deflection current | |
| US5614789A (en) | Apparatus and method of reducing varying electrical fields in video display terminals | |
| US4229787A (en) | Flyback transformer | |
| JP3989681B2 (en) | Deflection system | |
| GB2340707A (en) | Dynamic focus voltage amplitude controller | |
| US4187451A (en) | Color picture display device with a circuit for generating a screen grid voltage | |
| US4755727A (en) | Field deflection circuit for use in a picture display device | |
| EP0334658B1 (en) | Power supply | |
| GB2306872A (en) | An electromagnetic field shielding circuit for a display | |
| US6437523B1 (en) | Deflection circuits coupled via a filter | |
| JP3517441B2 (en) | Video display deflection device | |
| US4322664A (en) | Vertical ramp generator for a television receiver | |
| EP0114430B1 (en) | Picture display device comprising a power supply circuit and a line deflection circuit | |
| US6064581A (en) | High voltage transformer | |
| EP0562414A1 (en) | Sound intermediate frequency amplifier for a broadcast receiver | |
| JP2998344B2 (en) | Flyback transformer | |
| MXPA01006992A (en) | Deflection circuits coupled via a filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |