US3739327A - Electroacoustic transducers of the mass loaded vibratile piston type - Google Patents
Electroacoustic transducers of the mass loaded vibratile piston type Download PDFInfo
- Publication number
- US3739327A US3739327A US00098631A US3739327DA US3739327A US 3739327 A US3739327 A US 3739327A US 00098631 A US00098631 A US 00098631A US 3739327D A US3739327D A US 3739327DA US 3739327 A US3739327 A US 3739327A
- Authority
- US
- United States
- Prior art keywords
- transducer
- piston
- inertial mass
- housing
- electrical
- 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 - Lifetime
Links
- 239000000919 ceramic Substances 0.000 claims abstract description 42
- 230000000712 assembly Effects 0.000 claims description 18
- 238000000429 assembly Methods 0.000 claims description 18
- 238000007789 sealing Methods 0.000 claims description 8
- 239000012780 transparent material Substances 0.000 claims description 8
- 238000004382 potting Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 230000010355 oscillation Effects 0.000 claims description 4
- 230000002463 transducing effect Effects 0.000 claims description 4
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 2
- 239000013013 elastic material Substances 0.000 claims description 2
- 239000012530 fluid Substances 0.000 claims description 2
- 239000000615 nonconductor Substances 0.000 claims description 2
- 239000011888 foil Substances 0.000 abstract description 6
- 229910010293 ceramic material Inorganic materials 0.000 abstract description 3
- 239000004020 conductor Substances 0.000 description 5
- 238000010276 construction Methods 0.000 description 4
- 239000004593 Epoxy Substances 0.000 description 3
- 239000004568 cement Substances 0.000 description 3
- 229920001971 elastomer Polymers 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 241000557876 Centaurea cineraria Species 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- LJOOWESTVASNOG-UFJKPHDISA-N [(1s,3r,4ar,7s,8s,8as)-3-hydroxy-8-[2-[(4r)-4-hydroxy-6-oxooxan-2-yl]ethyl]-7-methyl-1,2,3,4,4a,7,8,8a-octahydronaphthalen-1-yl] (2s)-2-methylbutanoate Chemical compound C([C@H]1[C@@H](C)C=C[C@H]2C[C@@H](O)C[C@@H]([C@H]12)OC(=O)[C@@H](C)CC)CC1C[C@@H](O)CC(=O)O1 LJOOWESTVASNOG-UFJKPHDISA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 239000004359 castor oil Substances 0.000 description 1
- 235000019438 castor oil Nutrition 0.000 description 1
- 229940127204 compound 29 Drugs 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- ZEMPKEQAKRGZGQ-XOQCFJPHSA-N glycerol triricinoleate Natural products CCCCCC[C@@H](O)CC=CCCCCCCCC(=O)OC[C@@H](COC(=O)CCCCCCCC=CC[C@@H](O)CCCCCC)OC(=O)CCCCCCCC=CC[C@H](O)CCCCCC ZEMPKEQAKRGZGQ-XOQCFJPHSA-N 0.000 description 1
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 1
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 229920001084 poly(chloroprene) Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
- B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
- B06B1/0611—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile
- B06B1/0618—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile of piezo- and non-piezoelectric elements, e.g. 'Tonpilz'
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
- G01S1/72—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using ultrasonic, sonic or infrasonic waves
Definitions
- This type of transducer generally comprises a piezo-v electric cylindrical transducer element rigidly cemented between a vibratile piston and an inertial mass element.
- One of the problems which must be solved in such transducer structures concerns the need for making reliable electrical connections to electrode surfaces of the piezoelectric element. This reliability is generally accomplished by soldering flexible leads to the electrodes or by providing conducting foil electrodes which are held in mechanical contact with the electrode surfaces.
- the vibrations of the structure are likely to break these connections.
- a relatively high cost is required for the construction of these conventional electrode connections.
- an object of this invention is to improve the means for making electrical connection to the electrode surfaces of a piezoelectric element in a transducer.
- Another object of this invention is to eliminate wire leads making direct electrical connection to the electrode surfaces of the piezoelectric element in a trans ducer.
- a still further object of this invention is to utilize the basic component elements of the transducer vibrating assembly to complete the electrical connections to the piezoelectric element.
- an object is to avoid using electrical conductors or foil electrodes in direct contact with the piezoelectric element.
- Yet another object of this invention is to simplify the construction of mass loaded vibratile piston-type transducers, whereby a lower cost and an increased reliability is achieved, as compared to prior art structures.
- the terminals for the individual electrodes on the transducer element assemblies are two terminal lugs conveniently located at the rear of the assembled element. One lug attaches directly to the mass element, and the other lug attached to a stress bolt threaded into the vibratile piston.
- the invention provides a simplified construction of a transducer element assembly and completely eliminates the necessity for any direct wiring to electrode surfaces on the ceramic. This elimination enables a more reliable and less costly structure.
- FIG. 1 is a rear plan view of a mass loaded transducer assembly incorporating an illustrative embodiment of this invention
- FIG. 2 is a cross-sectional side view taken along the line 22 of FIG. 1;
- FIG. 3 is an end view of a first embodiment of a polarized ceramic transducer element that may be used in the transducer element assembly of FIG. 2;
- FIG; 4 is a cross-sectional side view taken along the line 4-4 of FIG. 3;
- FIG. 5 is an end view of another embodiment of a polarized ceramic transducer element that may be used in the transducer element assembly of FIG. 2;
- FIG. 6 is a cross-sectional side view taken along the line 6-6 of FIG. 5;
- FIG. 7 is a longitudinal partial cross-sectional view of a deep water transducer employing several of the element assemblies illustrated in FIG. 2;
- FIG. 8 is a cross-sectional view of the transducer assembly of FIG. 7 taken along the line 8-8 thereof.
- the reference character 11 identifies a vibratile piston which might be made of any suitable electrically conductive material, such as aluminum, for example.
- a cylindrical transducer element 12 may be made of any well known piezoelectric materials, such as barium titanate or lead-zirconate-titanate. As best seen in FIGS. 3 and 4, the ceramic 12 has electrode surfaces 13 and 14 (such as fired silver) formed on each end of the cylinder.
- An electrically conductive cylindrical inertial mass element 15 (FIG. 2) may be made of steel, for example.
- the electrode on one end of the hollow, polarized, piezoelectric ceramic cylinder 12 is bonded to one side of the piston 11.
- the mass element 15 is bonded to the electrode 14 on the opposite end of the ceramic cylinder.
- the bonding is accompished by means of a conducting cement, such as an epoxy mixed with a silver dust.
- the inertial mass element 15 has a clearance hole passing through its axis for receiving a stress bolt 19 for completing the assembly.
- an assembly may be completed by placing an insulating collar 17 over the stress bolt 19 and then putting a terminal lug 16 over the collar.
- Another terminal lug 18 is placed between the top of collar 17 and the bottom of the head on the stress bolt 19. All these parts are secured together by means of the stress bolts 19, which is tightened into a tapped hole machined into the piston 11.
- Any suitable spring means such as a Belleville spring washer (not shown) may be placed under the head of the screw 19 to control the compression stress applied to the ceramic cylinder 12.
- the assembly of FIG. 2 provides means for conveniently making electrical connections to the ceramic without requiring any direct connections of wires or foil to the electrodes. All electrical potentials appear at the terminal lugs 16 and 18 on the rear of the transducer assembly. This arrangement enables the wiring together of multiple transducer elements, when they are assembled as an array inside a housing structure.
- the ceramic cylinder 12 (FIGS. 2 and 4) has electrode surfaces on each of its two ends.
- the ceramic is axially polarized with the polarizing potentials and applied to the electrodes 13 and 14, as indicated.
- Another type of polarization for the ceramic element is illustrated in FIGS. 5 and 6.
- the tubular ceramic cylinder 20 has an electrode surface 21 on its inside wall and an electrode surface 22 on its outside wall.
- the ceramic material is radially polarized through the ceramic wall, with the polarizing potentials and applied as indicated.
- the positive electrode continues from the inside cylindrical wall and wraps over a portion of one end of the ceramic cylinder.
- the negative electrode continues from the outside cylindrical wall and wraps over a portion of the opposite end of the ceramic cylinder, as illustrated in FIG. 6.
- This radially polarized ceramic element 20 may be substituted for the ceramic element 12 in FIG. 2.
- Other types of electroacoustic transducer elements such as an X-cut quartz plate, for example, may also be substituted for the ceramic cylinder 12, in FIG. 2.
- FIGS. 7 and 8 show an illustrative embodiment of the inventive transducer assembly in a single transducer housing.
- a number of these transducer assemblies are arranged with their pistons 11 cemented to a sound conducting window 23, such as rubber or neoprene, for example. This cementing may be accomplished by means of epoxy (or another suitable cement).
- transducer assemblies are electrically wired together by means of a conductor 24, which is soldered to each of the common positive potential terminal lugs 16.
- a conductor 25 is soldered to each of the common negative potential terminal lugs 18.
- the conductors 24 and 25 are soldered to the terminals 26 and 27, which are sealed in a conventional insulated manner through the wall of the rigid housing structure 28.
- the periphery of the rubber window 23 is bonded to the open end of the housing 28, again by means of a suitable cement, such as epoxy.
- the space within the housing 28 is preferably filled with a rubbery potting compound 29, such as polyurethane or with a liquid such as castor oil. This filling is inserted into the housing through an opening, after which it is sealed by means of a threaded plug 30.
- a rubbery potting compound 29 such as polyurethane or with a liquid such as castor oil.
- the described invention eliminates direct wiring or foil connections to the electrode surfaces on the ceramic element. There is a simple, convenient, and reliable means for making a transducer assembly, which has great advantages over prior art structures.
- An electroacoustic transducer comprising an electrically conductive vibratile piston having at least one plane surface on one side thereof, an electrically conductive inertial mass element having at least one plane surface on one side thereof, piezoelectric transducer means for converting electrical oscillations into mechanical vibrations, said transducer means having a pair of opposite plane surfaces, separate electrode means formed directly on each of said pair of opposite plane surfaces of said transducer means, said integral electrode means being free of external connections, means for rigidly fastening said plane surface on said one side of said vibratile piston directly to one of said opposite plane surfaces of said transducer means and fastening said plane surface on said one side of said inertial mass element directly to said separate electrode means on the opposite surface of said transducer means, a first electrical terminal means connected to said inertial mass element, an electrically conductive bolt member attached to said piston, passing through said inertial mass member, and insulated from said mass member, and a second electrical terminal means electrically connected to said bolt member, whereby an electrical connection is made directly to
- transducer means comprises a polarized ceramic cylinder with said separate electrode on said opposite surfaces of said transducer means.
- said rigid fastening means includes a stress bolt for holding said piston and said inertial mass element tightly against the opposite end surfaces of said ceramic, whereby said ceramic is held in mechanical compression.
- An electroacoustic transducer comprising a vibratile piston having a pair of opposite plane surfaces, an inertial mass element having at least one plane surface, transducer means for converting electrical oscillations into mechanical vibrations, said transducer means having two parallel plane surfaces, electrode means integrally formed on at least a portion of each of said two parallel plane surfaces on said transducer means, mechanical fastening means for securely holding said piston, said inertial mass element, and said transducer means in direct physical contact free of any discrete electrode members having tabs for making external electrical connections thereto; said piston, said mass, and said transducer being held in axial alignment, one of said parallel plane surfaces of said transducer means being held in intimate mechanical contact with said plane surface of said inertial mass element, the other of said parallel plane surfaces of said transducer means being held in intimate mechanical contact with one of said plane surfaces of said piston means, a first electrical terminal means being connected to said inertial mass element, said mechanical fastening means comprising an electrically conductive bolt member attached to said piston, passing through
- transducer means is a hollow ceramic cylinder.
- said inertial mass element has an axial hole
- said mechanical fastening means including a stress bolt passing through said axial hole and applying axial compressive stress to said ceramic cylinder.
- a deep water transducer comprising a plurality of electrically conductive plate pistons flexibly connected to each other in a substantially planar alignmnt, a housing with an open side and one side of said planar alignment facing outwardly from said housing, a plurality of piezoelectric transducing elements, each element being held with one side in intimate contact with the other side of each of an individually associated one of said pistons, an electrically conductive inertial mass element held in intimate contact with the other side of each individually associated transducing element, a stress bolt interconnecting each of said mass elements and insulated from said mass elements and the associated plate piston for applying a stress to the associated one of said piezoelectric elements, said stress bolt making electrical contact with the associated plate piston, and means for electrically interconnecting said piezoelectrical elements via said mass elements and said stress bolts.
- transducer of claim 16 wherein said flexible connection is a sheet of elastic material sealing the open side of said housing.
Abstract
Description
Claims (17)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US9863170A | 1970-12-16 | 1970-12-16 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3739327A true US3739327A (en) | 1973-06-12 |
Family
ID=22270206
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00098631A Expired - Lifetime US3739327A (en) | 1970-12-16 | 1970-12-16 | Electroacoustic transducers of the mass loaded vibratile piston type |
Country Status (1)
Country | Link |
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US (1) | US3739327A (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4156863A (en) * | 1978-04-28 | 1979-05-29 | The United States Of America As Represented By The Secretary Of The Navy | Conical beam transducer array |
US4183007A (en) * | 1978-02-22 | 1980-01-08 | Fischer & Porter Company | Ultrasonic transceiver |
US4326275A (en) * | 1979-09-27 | 1982-04-20 | Hazeltine Corporation | Directional transducer |
US4649385A (en) * | 1982-08-13 | 1987-03-10 | Teloc R & D Ltd. | Electronic locating system for persons receiving telephone calls |
DE3635806A1 (en) * | 1985-11-27 | 1987-06-04 | Taga Electric Co Ltd | ULTRASONIC VIBRATOR |
US5726952A (en) * | 1996-05-18 | 1998-03-10 | Endress + Hauser Gmbh + Co. | Sound or ultrasound sensor |
DE102005056895A1 (en) * | 2005-11-28 | 2007-05-31 | Endress + Hauser Gmbh + Co. Kg | Device for determining and monitoring the fill level of a product in a container according to the transit time measurement method |
US20110051969A1 (en) * | 2008-05-07 | 2011-03-03 | Ixsea | Acoustic antenna having integrated printed circuits |
US20180032027A1 (en) * | 2016-07-29 | 2018-02-01 | Lexmark International, Inc. | Redundant electrical contact between a fastener and a component |
US11578928B2 (en) | 2019-02-13 | 2023-02-14 | Bae Systems Information And Electronic Systems Integration Inc. | Evaporative cooling for transducer array |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2724818A (en) * | 1951-08-21 | 1955-11-22 | Bendix Aviat Corp | Magnetostriction vibrator construction for directional transducers |
US3068446A (en) * | 1958-08-21 | 1962-12-11 | Stanley L Ehrlich | Tubular electrostrictive transducer with spaced electrodes and loading masses |
US3113761A (en) * | 1961-07-26 | 1963-12-10 | Ultrasonic Ind Inc | Ultrasonic tank housing |
US3150347A (en) * | 1959-11-30 | 1964-09-22 | Hanish Sam | Underwater transducer element |
US3218488A (en) * | 1961-08-01 | 1965-11-16 | Branson Instr | Transducer |
US3284761A (en) * | 1964-08-18 | 1966-11-08 | Westinghouse Electric Corp | Transducer |
US3328751A (en) * | 1966-03-28 | 1967-06-27 | Dynamics Corp Massa Div | Electroacoustic transducer |
US3329408A (en) * | 1965-03-29 | 1967-07-04 | Branson Instr | Transducer mounting arrangement |
US3478309A (en) * | 1968-04-10 | 1969-11-11 | Dynamics Corp America | Electroacoustic transducer with multiple beam characteristics |
US3525071A (en) * | 1968-04-10 | 1970-08-18 | Dynamics Corp America | Electroacoustic transducer |
-
1970
- 1970-12-16 US US00098631A patent/US3739327A/en not_active Expired - Lifetime
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2724818A (en) * | 1951-08-21 | 1955-11-22 | Bendix Aviat Corp | Magnetostriction vibrator construction for directional transducers |
US3068446A (en) * | 1958-08-21 | 1962-12-11 | Stanley L Ehrlich | Tubular electrostrictive transducer with spaced electrodes and loading masses |
US3150347A (en) * | 1959-11-30 | 1964-09-22 | Hanish Sam | Underwater transducer element |
US3113761A (en) * | 1961-07-26 | 1963-12-10 | Ultrasonic Ind Inc | Ultrasonic tank housing |
US3218488A (en) * | 1961-08-01 | 1965-11-16 | Branson Instr | Transducer |
US3284761A (en) * | 1964-08-18 | 1966-11-08 | Westinghouse Electric Corp | Transducer |
US3329408A (en) * | 1965-03-29 | 1967-07-04 | Branson Instr | Transducer mounting arrangement |
US3328751A (en) * | 1966-03-28 | 1967-06-27 | Dynamics Corp Massa Div | Electroacoustic transducer |
US3478309A (en) * | 1968-04-10 | 1969-11-11 | Dynamics Corp America | Electroacoustic transducer with multiple beam characteristics |
US3525071A (en) * | 1968-04-10 | 1970-08-18 | Dynamics Corp America | Electroacoustic transducer |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4183007A (en) * | 1978-02-22 | 1980-01-08 | Fischer & Porter Company | Ultrasonic transceiver |
US4156863A (en) * | 1978-04-28 | 1979-05-29 | The United States Of America As Represented By The Secretary Of The Navy | Conical beam transducer array |
US4326275A (en) * | 1979-09-27 | 1982-04-20 | Hazeltine Corporation | Directional transducer |
US4649385A (en) * | 1982-08-13 | 1987-03-10 | Teloc R & D Ltd. | Electronic locating system for persons receiving telephone calls |
DE3635806A1 (en) * | 1985-11-27 | 1987-06-04 | Taga Electric Co Ltd | ULTRASONIC VIBRATOR |
US5726952A (en) * | 1996-05-18 | 1998-03-10 | Endress + Hauser Gmbh + Co. | Sound or ultrasound sensor |
DE102005056895A1 (en) * | 2005-11-28 | 2007-05-31 | Endress + Hauser Gmbh + Co. Kg | Device for determining and monitoring the fill level of a product in a container according to the transit time measurement method |
US20110051969A1 (en) * | 2008-05-07 | 2011-03-03 | Ixsea | Acoustic antenna having integrated printed circuits |
US9114427B2 (en) * | 2008-05-07 | 2015-08-25 | Ixblue | Acoustic antenna having integrated printed circuits |
US20180032027A1 (en) * | 2016-07-29 | 2018-02-01 | Lexmark International, Inc. | Redundant electrical contact between a fastener and a component |
US10338518B2 (en) * | 2016-07-29 | 2019-07-02 | Lexmark International, Inc. | Redundant electrical contact between a fastener and a component |
US11578928B2 (en) | 2019-02-13 | 2023-02-14 | Bae Systems Information And Electronic Systems Integration Inc. | Evaporative cooling for transducer array |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TRUSTEES FOR AND ON BEHALF OF THE D.P. MASSA TRUST Free format text: ASSIGN TO TRUSTEES AS EQUAL TENANTS IN COMMON, THE ENTIRE INTEREST.;ASSIGNORS:MASSA, DONALD P.;MASSA, CONSTANCE A.;MASSA, GEORGIANA M.;AND OTHERS;REEL/FRAME:005395/0942 Effective date: 19841223 Owner name: MASSA PRODUCTS CORPORATION, 80 LINCOLN STREET, HIN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:DONALD P. MASSA TRUST;CONSTANCE ANN MASSA TRUST *;GEORGIANA M. MASSA TRUST;AND OTHERS;REEL/FRAME:005395/0954 Effective date: 19841223 Owner name: MASSA, DONALD P., COHASSET, MA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:STONELEIGH TRUST, THE;REEL/FRAME:005397/0016 Effective date: 19841223 Owner name: MASSA PRODUCTS CORPORATION, 280 LINCOLN STREET, HI Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:DONALD P. MASSA TRUST;CONSTANCE ANN MASSA TRUST;ROBERT MASSA TRUST;AND OTHERS;REEL/FRAME:005395/0971 Effective date: 19860612 Owner name: DELLORFANO, FRED M. JR. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:STONELEIGH TRUST, THE;REEL/FRAME:005397/0016 Effective date: 19841223 |