CA1080343A - Coil and microphone mounting for frequency correction in mechanical resonators - Google Patents
Coil and microphone mounting for frequency correction in mechanical resonatorsInfo
- Publication number
- CA1080343A CA1080343A CA259,134A CA259134A CA1080343A CA 1080343 A CA1080343 A CA 1080343A CA 259134 A CA259134 A CA 259134A CA 1080343 A CA1080343 A CA 1080343A
- Authority
- CA
- Canada
- Prior art keywords
- mounting
- coil
- sleeve
- microphone
- end plate
- 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
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H13/00—Measuring resonant frequency
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/013—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for obtaining desired frequency or temperature coefficient
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Details Of Audible-Bandwidth Transducers (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
- Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
Abstract
Abstract of the Disclosure A coil and microphone mounting for receiving an excitation coil and a microphone transducer in a protective housing having a detachable end plate provided with a throughgoing tube allowing pressure waves to reach the trans-ducer and with throughgoing ferrite core elements allowing magnetic flux from the coil to escape. The mounting has particular application to connec-tion of mechanical resonators by laser bombardment or sand blasting during which the transducer and coil are protected by the end plate.
Description
The present invention relates to coil and microphone mountings.
Although the term "microphone transducer'f will be used hereinafter to describe the invention, it will be understood that by this term is meant anyform of electro-acoustic transducer responsiue to pressure waves which are in the - range from sub-sonic to ultrasonic values of frequency.
When mechanical resonators for electromechanical filters are corrected, these devices are excited by the a.c. field of a coil to perform mechanical vibrations and the frequency of these vibrations is measured with the help of a microphone transducer.
In this context, for example~ a method of effecting frequency correction in mechanical resonators is known in which the adjustment of the predetermined resonance frequency is performed by the controlled removal of resonator material using a sand-blaster or a laser beam (German Patent Specification No. 1 929 99~). The resonators are excited ( i by the a.c. field of a coil havinc3 an iron core in order to perform mechanical vibrations which are converted by a microphone transducer into electrical oscillations correspond-ing to the actual frequency of the resonators. These elect-rical oscillations are amplified and are then subjected to a comparison between set-point and actual values and in accordance with the resultant frequency difference, the removal of resonator material by laser or sand blaster is controlled.
Although the term "microphone transducer'f will be used hereinafter to describe the invention, it will be understood that by this term is meant anyform of electro-acoustic transducer responsiue to pressure waves which are in the - range from sub-sonic to ultrasonic values of frequency.
When mechanical resonators for electromechanical filters are corrected, these devices are excited by the a.c. field of a coil to perform mechanical vibrations and the frequency of these vibrations is measured with the help of a microphone transducer.
In this context, for example~ a method of effecting frequency correction in mechanical resonators is known in which the adjustment of the predetermined resonance frequency is performed by the controlled removal of resonator material using a sand-blaster or a laser beam (German Patent Specification No. 1 929 99~). The resonators are excited ( i by the a.c. field of a coil havinc3 an iron core in order to perform mechanical vibrations which are converted by a microphone transducer into electrical oscillations correspond-ing to the actual frequency of the resonators. These elect-rical oscillations are amplified and are then subjected to a comparison between set-point and actual values and in accordance with the resultant frequency difference, the removal of resonator material by laser or sand blaster is controlled.
- 2 -: ' ' ',, ' ',' ' ' ' ''"' ' ' ' "' -.
: . . . - . :
10~ 3 - .
In order~ in determining the characteristic frequency of the mechanical resonator, to achieve an adequately large vibrational amplitude, it is preferable for that air gap between the iron core of the excitation coil and the resonator which closes the magnetic circuit to be kept small. The microphone transducer should, in order to - furnish the highest possible output voltage, be arranged in the proximity of a vibrational antinode in the air column between resonator and microphone transducer.
In order~ furthermore, to exclude the effects of ; environmental noise during measurement of the characteristic frequency of the resonators, it is preferable to arrange the microphone transducer in the neighbourhood of the first vibrational antinode in the air column. This results in an interval, between resonator and microphone, of only a few tenths of a millimeter. However, because measurement of the characteristic frequency generally takes place in alteration with the step-by-step operation of frequency correction~ the excitation coil and the microphone transducer are in the known system~ subject to heavy wear either by reflected sand grains or, in the case of lasér bombardment, by particles of `~ material knocked out in the course of laser machining.
An object of the invention is to improve upon the known system by overcoming the aforesaid difficulties.
~ccording to the invention, there is provided a coil and microphone mounting~ for receiving an excitation coil and a microphone transducer~ comprising: an elongate housing ,: . -:l ' . , .
,, ~
, . ' . : : ' . . ' '' ' -having a detachable protective end plate; a sleeve disposed within the housing for enclosing said microphone transducer, one en~ of the sleeve extending through said end plate; two magnetic core elements extending through said end plate; and a magnetic core, for said coil, displaceable within the housing and externally of said sleeve in such manner that it can be brought into contact with said core elements.
Preferably æaid sleeve comprises two cylindrical portions of differing diameters connected together by means of a corresponding tapering tube section, that cylindrical portion having the smaller diameter being detachable from the taper-ing section and extending through said end plate.
Preferably, the mounting further comprises means for supporting the microphone in such manner that it can be displaced in the direction of the longitudinal axis of the sleeve and comprises means for locking the microphone trans-ducer to prevent it from being thus displaced.
Where the mounting according to the invention is in operable combination with an excitation coil and a microphone .. ..
transducer, the detecting part of the microphone transducer may be arranged at a vibrational antinode of that air column located within said sleeve.
The mounting according to the invention may be provided with support means for supporting a mechanical resonator adjacent said end plate. There may further be provided holding means for holding a sand blaster and/or a laser in such positions or position that they or it can adjust the resonant frequency of a mechanical resonator when it is .
: ' ' . : . , -, :- - . . : . ~: -supported by said support means.
For a better understan~ing of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the drawings, in which:
Figure 1 is a schematic view of a frequency correction device of prior art design;
Figure 2 is a schematic illustration of a coil and microphone mounting in accordance with the invention;
Figure 3 illustrates schematically a vertical section through the mounting of Figure 2, passing through the centre of the microphone; and Figure 4 illustrates schematically a section taken vertically in relation to that of Figure 3.
Figure 1 illustrates a known correcting device with a laser unit 2 aimed at one end of the resonator 1 which is to be corrected. A frequency measuring unit consisting of an excitation coil 3 and a microphone 4 having a microphone transducer ~ is here disposed at an interval o only a few tenths of a millimeter from the resonator 1 which is to be corrected. Because of the requisite short interval, both the microphone transducer 4' and coil 3 are subject to heavy wear as a consequence of the particles of material knocked out by laser bombardment. This means that frequent replace-ment of the coil and the expensive microphone transducer, is necessary. Corresponding conditions apply to the situation in which correction is performed by sand-blasting.
In Figure 2, a frequency measuring unit in accordance ~ 5 .
.
, .
.
:
.
' 108~)343 , with the invention is shown schematically. A coil 3 and a microphone 4 having a microphone transducer 4' are-arranged behind~a detachable protective end plate 5 of a housing 9, the plate 5 being of insulating material. Passing through this protective plate 5 are two core elements 6 of magnetic material (e.g. ferrite) which extend the magnetic iron circuit of an excitation coil 3 in such a way that once again a very small air~gap is left between resonator l and a core ll of coil 3. To protect the microphone transducer 4', a cylindrical sleeve 7 is provided into which the microphone transducer 4' projects. The sleeve 7 is tapered at one end and terminates in a tube section 8 of correspondingly smaller diameter which is screwed into the sleeve 7 and projects through the protective plate 5. Section 8 is thus readily detachable from sleeve 7. The end of the tube section 8 is taken up to a point close to the resonator 1. The sleeve 7 , cooperates with the tube section 8 to form a resonant column in which an air column vibrating at the ~requency of the resonator forms~ said air column being little affected by environrnental noise. The microphone transducer 4' can there-fore~ without substantial impairment of the measurement conditions~ be arranged at a vibrational antinode in the air column, which is located further away from the resonator 1. Because the protective plate 5, with the core elements 6 in position in it, is screwed on to housing 9, it can readily be replaced in the same way as the tube section 8 screwed on to the sleeve 7.
::, " -.
- . . - . : .
. . :: - : . ~ ' . , .: , - . -: -~80343 It is clear from Figures 3 and 4 how the sleeve 7 enclosing the microphone 4, and the tube section 8, are located between the arms of a U-shaped core 11 of the excitation coil 3 and between the core elements 6. The excitation coil 3 which is arranged laterally of sleeve 7 within the protective housing 9, can be displaced, by the screw 10, longitudinally of the housing 9 so that the coil cores 11 abut against the two core elements 6. A~screw 12 is used to lock the coil in position after it has been adjusted.
The sleeve 7 provided to protect the microphone 4 is tapered at that of its ends Eacing the resonator 1. By means ; of a tube section 8 screwed on to this end of the sleeve 7 and passing through a bore in the protective plate 5, connection with the resonator 1 is established. The micro- `
phone 4 is housed in insulated fashion in the protective housing 9, within a synthetic plastics material sleeve 13 which can be rotated about its own longitudinal axis~ and can be displaced within said sleeve 13 in the direction of its own longitudinal axis, a clamping element 14 being provided to lock it in position as required. one end of the synthetic plastics material sleeve 13 carries a thread 15 on to which the sleeve 7 is screwed. Thus, by rotating the synthetic plastics material sleeve 13, the sleeve 7 can be dlsplaced in the direction of its own longitudinal axis and the interval between the tube section ~ and the resonator 1 adjusted.
i , ~. , . . - . , -. : ~ -. . --, .
108~343 An arm 16 prevents rotation of sleeve 7 during this adjustment~
The protective housing 9 is closed off at its sides by respective plates 17 so that the only wearing parts are the protective end plate 5 with the two core elements 6 and the tube section 8. These wearing parts can be manufactured quite simply and are easy to replace.
A major advantage of the system in accordance with the invention thus arises from the fact that microphone and coil are effectively protected and that all components subject to wear are readily exchangeable~ Moreover, these wearing parts can be replaced relatively cheaply ~o that the overall economy is high.
Also, the probability that sand grains reflected from or particles of material knocked out of the resonator, will reach the microphone transducer is low. The tube element which experiences substantial wear~ can be relatively cheap and be readily replaced.
'' ' ' ' . ' '. ,'' ' ' .'. : '' :
: . . . - . :
10~ 3 - .
In order~ in determining the characteristic frequency of the mechanical resonator, to achieve an adequately large vibrational amplitude, it is preferable for that air gap between the iron core of the excitation coil and the resonator which closes the magnetic circuit to be kept small. The microphone transducer should, in order to - furnish the highest possible output voltage, be arranged in the proximity of a vibrational antinode in the air column between resonator and microphone transducer.
In order~ furthermore, to exclude the effects of ; environmental noise during measurement of the characteristic frequency of the resonators, it is preferable to arrange the microphone transducer in the neighbourhood of the first vibrational antinode in the air column. This results in an interval, between resonator and microphone, of only a few tenths of a millimeter. However, because measurement of the characteristic frequency generally takes place in alteration with the step-by-step operation of frequency correction~ the excitation coil and the microphone transducer are in the known system~ subject to heavy wear either by reflected sand grains or, in the case of lasér bombardment, by particles of `~ material knocked out in the course of laser machining.
An object of the invention is to improve upon the known system by overcoming the aforesaid difficulties.
~ccording to the invention, there is provided a coil and microphone mounting~ for receiving an excitation coil and a microphone transducer~ comprising: an elongate housing ,: . -:l ' . , .
,, ~
, . ' . : : ' . . ' '' ' -having a detachable protective end plate; a sleeve disposed within the housing for enclosing said microphone transducer, one en~ of the sleeve extending through said end plate; two magnetic core elements extending through said end plate; and a magnetic core, for said coil, displaceable within the housing and externally of said sleeve in such manner that it can be brought into contact with said core elements.
Preferably æaid sleeve comprises two cylindrical portions of differing diameters connected together by means of a corresponding tapering tube section, that cylindrical portion having the smaller diameter being detachable from the taper-ing section and extending through said end plate.
Preferably, the mounting further comprises means for supporting the microphone in such manner that it can be displaced in the direction of the longitudinal axis of the sleeve and comprises means for locking the microphone trans-ducer to prevent it from being thus displaced.
Where the mounting according to the invention is in operable combination with an excitation coil and a microphone .. ..
transducer, the detecting part of the microphone transducer may be arranged at a vibrational antinode of that air column located within said sleeve.
The mounting according to the invention may be provided with support means for supporting a mechanical resonator adjacent said end plate. There may further be provided holding means for holding a sand blaster and/or a laser in such positions or position that they or it can adjust the resonant frequency of a mechanical resonator when it is .
: ' ' . : . , -, :- - . . : . ~: -supported by said support means.
For a better understan~ing of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the drawings, in which:
Figure 1 is a schematic view of a frequency correction device of prior art design;
Figure 2 is a schematic illustration of a coil and microphone mounting in accordance with the invention;
Figure 3 illustrates schematically a vertical section through the mounting of Figure 2, passing through the centre of the microphone; and Figure 4 illustrates schematically a section taken vertically in relation to that of Figure 3.
Figure 1 illustrates a known correcting device with a laser unit 2 aimed at one end of the resonator 1 which is to be corrected. A frequency measuring unit consisting of an excitation coil 3 and a microphone 4 having a microphone transducer ~ is here disposed at an interval o only a few tenths of a millimeter from the resonator 1 which is to be corrected. Because of the requisite short interval, both the microphone transducer 4' and coil 3 are subject to heavy wear as a consequence of the particles of material knocked out by laser bombardment. This means that frequent replace-ment of the coil and the expensive microphone transducer, is necessary. Corresponding conditions apply to the situation in which correction is performed by sand-blasting.
In Figure 2, a frequency measuring unit in accordance ~ 5 .
.
, .
.
:
.
' 108~)343 , with the invention is shown schematically. A coil 3 and a microphone 4 having a microphone transducer 4' are-arranged behind~a detachable protective end plate 5 of a housing 9, the plate 5 being of insulating material. Passing through this protective plate 5 are two core elements 6 of magnetic material (e.g. ferrite) which extend the magnetic iron circuit of an excitation coil 3 in such a way that once again a very small air~gap is left between resonator l and a core ll of coil 3. To protect the microphone transducer 4', a cylindrical sleeve 7 is provided into which the microphone transducer 4' projects. The sleeve 7 is tapered at one end and terminates in a tube section 8 of correspondingly smaller diameter which is screwed into the sleeve 7 and projects through the protective plate 5. Section 8 is thus readily detachable from sleeve 7. The end of the tube section 8 is taken up to a point close to the resonator 1. The sleeve 7 , cooperates with the tube section 8 to form a resonant column in which an air column vibrating at the ~requency of the resonator forms~ said air column being little affected by environrnental noise. The microphone transducer 4' can there-fore~ without substantial impairment of the measurement conditions~ be arranged at a vibrational antinode in the air column, which is located further away from the resonator 1. Because the protective plate 5, with the core elements 6 in position in it, is screwed on to housing 9, it can readily be replaced in the same way as the tube section 8 screwed on to the sleeve 7.
::, " -.
- . . - . : .
. . :: - : . ~ ' . , .: , - . -: -~80343 It is clear from Figures 3 and 4 how the sleeve 7 enclosing the microphone 4, and the tube section 8, are located between the arms of a U-shaped core 11 of the excitation coil 3 and between the core elements 6. The excitation coil 3 which is arranged laterally of sleeve 7 within the protective housing 9, can be displaced, by the screw 10, longitudinally of the housing 9 so that the coil cores 11 abut against the two core elements 6. A~screw 12 is used to lock the coil in position after it has been adjusted.
The sleeve 7 provided to protect the microphone 4 is tapered at that of its ends Eacing the resonator 1. By means ; of a tube section 8 screwed on to this end of the sleeve 7 and passing through a bore in the protective plate 5, connection with the resonator 1 is established. The micro- `
phone 4 is housed in insulated fashion in the protective housing 9, within a synthetic plastics material sleeve 13 which can be rotated about its own longitudinal axis~ and can be displaced within said sleeve 13 in the direction of its own longitudinal axis, a clamping element 14 being provided to lock it in position as required. one end of the synthetic plastics material sleeve 13 carries a thread 15 on to which the sleeve 7 is screwed. Thus, by rotating the synthetic plastics material sleeve 13, the sleeve 7 can be dlsplaced in the direction of its own longitudinal axis and the interval between the tube section ~ and the resonator 1 adjusted.
i , ~. , . . - . , -. : ~ -. . --, .
108~343 An arm 16 prevents rotation of sleeve 7 during this adjustment~
The protective housing 9 is closed off at its sides by respective plates 17 so that the only wearing parts are the protective end plate 5 with the two core elements 6 and the tube section 8. These wearing parts can be manufactured quite simply and are easy to replace.
A major advantage of the system in accordance with the invention thus arises from the fact that microphone and coil are effectively protected and that all components subject to wear are readily exchangeable~ Moreover, these wearing parts can be replaced relatively cheaply ~o that the overall economy is high.
Also, the probability that sand grains reflected from or particles of material knocked out of the resonator, will reach the microphone transducer is low. The tube element which experiences substantial wear~ can be relatively cheap and be readily replaced.
'' ' ' ' . ' '. ,'' ' ' .'. : '' :
Claims (11)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:-
1. A coil and microphone mounting, for receiving an excitation coil and a microphone transducer, comprising: an elongate housing having a detachable protective end plate;
a sleeve disposed within the housing for enclosing said microphone transducer one end of the sleeve extending through said end plate; two magnetic core elements extending through said end plate; and a magnetic core, for said coil, displace-able within the housing and externally of said sleeve in such manner that it can be brought into contact with said core elements.
a sleeve disposed within the housing for enclosing said microphone transducer one end of the sleeve extending through said end plate; two magnetic core elements extending through said end plate; and a magnetic core, for said coil, displace-able within the housing and externally of said sleeve in such manner that it can be brought into contact with said core elements.
2. A mounting as claimed in Claim 1 wherein said sleeve comprises two cylindrical portions of differing diameters connected together by means of a corresponding tapering tube section, that cylindrical portion having the smaller diameter being detachable from the tapering section and extending through said end plate.
3. A mounting as claimed in Claim 1, and which further comprises means for supporting the microphone in such manner that it can be displaced in the direction of the longitudinal axis of the sleeve and comprises means for locking the microphone transducer to prevent it from being thus displaced.
4. A mounting as claimed in any one of Claims 1 to 3 wherein said core elements are of ferrite.
5. A mounting as claimed in any one of Claims 1 to 3 wherein said end plate is of electrically insulating material.
6. A mounting as claimed in Claim 1 when in operable combination with an excitation coil and a microphone transducer.
7. A mounting as claimed in Claim 6 wherein the microphone transducer is arranged at a vibrational antinode of that air column located with said sleeve.
8. A mounting as claimed in Claim 1 wherein there is provided support means for supporting a mechanical resonator adjacent said end plate.
9. A mounting as claimed in Claim 8 wherein a mechanical resonator is supported by said support means.
10. A mounting as claimed in Claim 8 wherein there is provided holding means for holding a sand blaster and/or a laser in such positions or position that they or it can adjust the resonant frequency of a mechanical resonator when it is supported by said support means.
11. A mounting as claimed in Claim 10 in operable combination with a sand blaster and/or a laser.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2543128A DE2543128C3 (en) | 1975-09-26 | 1975-09-26 | Coil and microphone holder for a frequency adjustment device for mechanical resonators |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1080343A true CA1080343A (en) | 1980-06-24 |
Family
ID=5957597
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA259,134A Expired CA1080343A (en) | 1975-09-26 | 1976-08-16 | Coil and microphone mounting for frequency correction in mechanical resonators |
Country Status (22)
| Country | Link |
|---|---|
| JP (1) | JPS5832802B2 (en) |
| AT (1) | AT356710B (en) |
| BE (1) | BE846587A (en) |
| BR (1) | BR7606369A (en) |
| CA (1) | CA1080343A (en) |
| CH (1) | CH609505A5 (en) |
| CS (1) | CS208191B2 (en) |
| DE (1) | DE2543128C3 (en) |
| DK (1) | DK143009C (en) |
| ES (1) | ES451815A1 (en) |
| FR (1) | FR2326076A1 (en) |
| GB (1) | GB1534605A (en) |
| GR (1) | GR60578B (en) |
| HU (1) | HU172595B (en) |
| IE (1) | IE43049B1 (en) |
| IL (1) | IL50277A (en) |
| IT (1) | IT1068347B (en) |
| LU (1) | LU75494A1 (en) |
| NL (1) | NL168095C (en) |
| PT (1) | PT65647B (en) |
| YU (1) | YU225676A (en) |
| ZA (1) | ZA764967B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1587123A (en) * | 1976-11-12 | 1981-04-01 | Emi Ltd | Measuring arrangements for electrical signals |
-
1975
- 1975-09-26 DE DE2543128A patent/DE2543128C3/en not_active Expired
-
1976
- 1976-07-29 LU LU75494A patent/LU75494A1/xx unknown
- 1976-07-30 CH CH974176A patent/CH609505A5/en not_active IP Right Cessation
- 1976-08-06 GB GB32914/76A patent/GB1534605A/en not_active Expired
- 1976-08-12 AT AT599876A patent/AT356710B/en not_active IP Right Cessation
- 1976-08-16 CA CA259,134A patent/CA1080343A/en not_active Expired
- 1976-08-16 IE IE1806/76A patent/IE43049B1/en unknown
- 1976-08-16 IL IL50277A patent/IL50277A/en unknown
- 1976-08-18 ZA ZA764967A patent/ZA764967B/en unknown
- 1976-09-02 FR FR7626495A patent/FR2326076A1/en active Granted
- 1976-09-15 YU YU02256/76A patent/YU225676A/en unknown
- 1976-09-20 CS CS766080A patent/CS208191B2/en unknown
- 1976-09-21 IT IT27439/76A patent/IT1068347B/en active
- 1976-09-24 DK DK432576A patent/DK143009C/en active
- 1976-09-24 BR BR7606369A patent/BR7606369A/en unknown
- 1976-09-24 PT PT65647A patent/PT65647B/en unknown
- 1976-09-24 JP JP51114571A patent/JPS5832802B2/en not_active Expired
- 1976-09-24 ES ES451815A patent/ES451815A1/en not_active Expired
- 1976-09-24 HU HU76SI00001542A patent/HU172595B/en unknown
- 1976-09-24 NL NL7610623A patent/NL168095C/en not_active IP Right Cessation
- 1976-09-24 BE BE170940A patent/BE846587A/en unknown
- 1976-09-25 GR GR51780A patent/GR60578B/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| ATA599876A (en) | 1979-10-15 |
| ZA764967B (en) | 1977-07-27 |
| DE2543128C3 (en) | 1978-03-16 |
| IL50277A (en) | 1979-03-12 |
| DE2543128A1 (en) | 1977-03-31 |
| BE846587A (en) | 1977-01-17 |
| JPS5242349A (en) | 1977-04-01 |
| DE2543128B2 (en) | 1977-07-21 |
| NL7610623A (en) | 1977-03-29 |
| AT356710B (en) | 1980-05-27 |
| GB1534605A (en) | 1978-12-06 |
| YU225676A (en) | 1982-05-31 |
| HU172595B (en) | 1978-10-28 |
| IE43049B1 (en) | 1980-12-03 |
| GR60578B (en) | 1978-06-28 |
| PT65647B (en) | 1978-04-07 |
| DK143009C (en) | 1981-10-19 |
| IL50277A0 (en) | 1976-10-31 |
| LU75494A1 (en) | 1977-03-03 |
| PT65647A (en) | 1976-10-01 |
| DK432576A (en) | 1977-03-27 |
| FR2326076B1 (en) | 1978-11-03 |
| ES451815A1 (en) | 1977-11-01 |
| CS208191B2 (en) | 1981-08-31 |
| DK143009B (en) | 1981-03-09 |
| NL168095B (en) | 1981-09-16 |
| AU1710476A (en) | 1977-11-17 |
| IT1068347B (en) | 1985-03-21 |
| CH609505A5 (en) | 1979-02-28 |
| FR2326076A1 (en) | 1977-04-22 |
| NL168095C (en) | 1982-02-16 |
| IE43049L (en) | 1977-03-26 |
| JPS5832802B2 (en) | 1983-07-15 |
| BR7606369A (en) | 1977-05-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |