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US3907092A - Matrix wire print head with free bending print wires - Google Patents

Matrix wire print head with free bending print wires Download PDF

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Publication number
US3907092A
US3907092A US378774A US37877473A US3907092A US 3907092 A US3907092 A US 3907092A US 378774 A US378774 A US 378774A US 37877473 A US37877473 A US 37877473A US 3907092 A US3907092 A US 3907092A
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US
United States
Prior art keywords
print
wires
wire
openings
print head
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
Application number
US378774A
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English (en)
Inventor
Okun Kwan
James Vincent Masi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bunker Ramo Corp
Allied Corp
Original Assignee
Bunker Ramo Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Bunker Ramo Corp filed Critical Bunker Ramo Corp
Priority to US378774A priority Critical patent/US3907092A/en
Priority to GB2315974A priority patent/GB1470534A/en
Priority to CA201,153A priority patent/CA1010294A/en
Priority to DE2430440A priority patent/DE2430440A1/de
Priority to SE7408857A priority patent/SE402497B/sv
Priority to FR7424178A priority patent/FR2236661A1/fr
Priority to JP49080093A priority patent/JPS5037511A/ja
Priority to IT25119/74A priority patent/IT1017124B/it
Application granted granted Critical
Publication of US3907092A publication Critical patent/US3907092A/en
Assigned to ALLIED CORPORATION A CORP. OF NY reassignment ALLIED CORPORATION A CORP. OF NY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: BUNKER RAMO CORPORATION A CORP. OF DE
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
    • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
    • B41J2/235—Print head assemblies
    • B41J2/265—Guides for print wires

Definitions

  • ABSTRACT This invention relates to an improved wire matrix print head having significantly reduced friction on the print wires and to a method for the manufacture of the improved print head.
  • the print head has an element formed at one end for mounting the nonprinting end of the wires and a print guide member having end openings arranged in a predetermined print pattern mounted at the other end of the print head, the print wires each passing through and being supported in a separate one of the openings.
  • First and second guide plates are also provided, each of the plates having n openings formed therethrough which openings are arranged in predetermined patterns and through which openings the print wires are adapted to pass. Each wire passes through a separate opening in each of the guide plates.
  • the guide plates are mounted at predetermined positions between the nonprinting end of the wires and the print guide member. The predetermined positions are selected such that the first guide plate is spaced from the print guide member by a first predetermined distance, the guide plates are spaced from, each other by a second predetermined distance, and the second guide plate is spaced from the nonprinting ends of the wires by a third predetermined distance, the first, second and third predetermined distances all being shorter than the critical length for the print wire to prevent buckling.
  • the predetermined positions at which the guide plates are mounted are also both within one-eighth wave-length of the peak deflection points of a print wire when the wire is vibrating at its natural frequency of vibration.
  • the print head is of the type having a single column of n print wires and the print guide member has its n openings alined one on top of the other, there being a predetermined spacing between adjacent openings.
  • the nonprinting ends of the wires are mounted with one wire in the middle and the other (n-l wires substantially symmetrically positioned around the one wire with the angular spacing between adjacent wires being substantially equal.
  • the guide plates each have a center opening through which one wire passes, and (n-1) other openings positioned around the center opening through a separate one of which each of the other (nl) wires passes.
  • the spacing of each of the openings from the corresponding center opening is a function of the natural deflection of the print wire passing therethrough at the predetermined position of the guide plate.
  • MATRIX WIRE PRINT HEAD WITH FREE BENDING PRINT WIRES This invention relates to an improved wire matrix print head having significantly reduced friction on the print wires and to a method for the manufacture of the improved print head.
  • Wire matrix print heads because of their light weight and short print stroke, are used extensively in high speed electronic printers. Some of these print heads contain enough print wires to print a whole character (for example, 35 wires arranged in a 5 X7 matrix). However, lighter weight and simpler heads containing only a single column of print wires have been found more suitable for high speed printing, particularly when printing on the fly. With the latter tyoe of head, the head is energized once for each stroke of the character. Thus, for a character formed from a 5 7matrix of dots, the head would contain seven print wires and would be selectively actuated five times for each character. A print head of this type is disclosed in some detail in the US. Pat. No. 3,690,431, entitled PrintheadAssembly Containing Solenoids, issued Sept. 12, 1972 to Robert Howard. 1
  • Matrix wire print heads of the type indicated above normally employ a separate solenoid for advancing each print wire to a print position with a separate-spring being provided to return the wire to its initial position. Since the spacing between the wires at the print end of the print head is very small, normallybeing in the order of a few thousandths of an inch, the wires mustbe bent in the print head to provide adequate room at the rear of the head for mounting the drive solenoids, return springs, and other print control elements. Guide elements must therefore also be provided in the print head to lead the wires from the solenoids to the print position at the front of the head.
  • wires being relatively thin, tend to buckle and vibrate when they impact a document during a print operation.
  • print heads such as that described in the above-mentioned Howard patentQprovi'de guide tubes along most of the length of the wire through which the wire is passed.
  • the use of the guide tubes creates critical alinement'problems which, in addition to the wear on the wires and'gui'des resulting from friction, results in increased maintenance requirements on the head and significantlyreduces the life of the heads and of the various elements thereof. Since the heads are designed to operate'at speeds of up to 200 characters per second, the heads are being'open ated at speeds of up to 1,200 operations per second. Friction between the print wire and guide tubes or plates thus also results in significant heat which causes further damage to the components of the head and creates dissipation problems. The problems indicated above also serve to limit the speed at which the head may be operated without serious damage.
  • this invention provides a print head of the type having a matrix of n print wires.
  • a print head of the type having a matrix of n print wires.
  • First and second guide plates are also provided, each of the plates having n openings formed therethrough which openings are arranged in predetermined patterns and through which openings the print wires are adapted to pass. Each wire passes through a separate opening in each of the guide plates.
  • the head has a means for mounting the guide plates at predetermined positions between the means for mounting the nonprinting end of the wires and the print guide member.
  • the predetermined positions are selected such that the first guide plate is spaced from the print guide member by a first predetermined distance, the guide plates are spaced from each other by a second predetermined distance, and the second guide plate is spaced from the means for supporting the nonprinting ends of the wires by a third predetermined distance, the first, second and third predetermined distances all being shorter than the critical length for the print wire to prevent buckling.
  • the predetermined positions :at which the guide plates are mounted are also both within one-eighth wavelength of the peak deflection points of a print wire when the wire is vibrating at its natural frequency of vi bration.
  • the print head is of the type having a single column of n print wires and the print guide member has its n openings aligned one on top of the other, there being a predetermined spacing between adjacent openings.
  • the means for mounting the nonprinting ends of the wires mounts the wires with one wire in the middle and the other (n 1) wires substantially symmetrically positioned around the one wire with the angular spacing between adjacent wires being substantially equal.
  • the guide plates each have a center opening through which one wire passes, and (11-1) other openings positioned around the center opening through a separate one of which each of the other (n-I) wires passes.
  • the spacing of each of the openings from the corresponding center opening is a function of the natural deflection of the print wire passing therethrough at the predetermined position of the guide plate.
  • FIG. 1 is a partially cut-awaytop view of a print head of a preferred'embodiment of the invention.
  • FIG. 2 is a sectional side view of the print head taken along the line 22 of FIG. 1.
  • FIG. 3 is a back view of the print head shown in FIG.
  • FIG. 4 is a partial sectional view along the line 44 of FIG. 2 showing the back guide plate and also illustrating some of the parameters utililzed in determining the positions of the openings in this plate.
  • FIG. 5 is a partial sectional view along the line 5-5 of FIG. 2 showing the front guide plate and some of the parameters utilized in determining the positions of the openings in this plate.
  • FIG. 6 is a partial front view taken along the line 66 ofFIG. 2 showing the print guide member.
  • FIG. 7 is a diagram of a print wire illustrating some of the parameters utilized in making the various'positioning determinations of this invention.
  • FIG. 8 is an enlarged view of the left portion of FIG. 7, illustrating additional parameters utilized in making the positioning determinations.
  • FIG..9 is a diagram of a print wire illustrating its vibration modes'and some-additional positioning parameters.
  • the print head 10 of this invention has a metallic housing1l2 with a raised rear wall 14. Seven solenoid assemblies 16v are mounted in corresponding openings 17 in the rear wall 14. A print wire 18 projects from each solenoid assembly 16.
  • Each of the solenoid assemblies 16 may be considered to be of the type shown in the beforementioned Howard patent with the wire 18 terminating in and being attached to the armature of a solenoid (not shown) and the armature terminating in and being attached to the hub of a wagon wheel or other shaped spring.
  • a jewel 20 having seven alined openings 22 formed therein.
  • a corresponding print wire 18 is supported in each of the openings 22 with the end of the wire normally being flush with the front surface of the jewel.
  • the center-tocenter spacing of the openings 22 is quite small, being 14 mils (14-thousandths of an inch) for an exemplary embodiment of the invention.
  • the size of the openings 22 is slightly larger than the diameter of the wires 18.
  • Housing 12 also has a first pair of guide slots or brackets 24 and a second pair of guide slots or brackets 26 formed therein.
  • a first guide plate 28 having seven openings 30 formed therethrough (FIG. 5) is mounted in brackets 24 and a second guide plate 32 having seven openings 34 (FIG. 4) formed therethrough is mounted in brackets 26.
  • Each of the openings 30 has a diameter which is slightly larger than the diameter of the print wire 18 while each of the openings 34 has a somewhat larger diameter. For example, with a wire di ameter of 14 mils, the diameter of the openings 30 might be 16 mils and the diameter of the openings 34, 22 mils.
  • the locations of the plates 28 and 32 in housing 12 and the location of the openings 30 and 34 in their respective plates are critical to the improved performance of the print head and the manner in which these positions are selected will be described shortly.
  • print head 10 which elements do not form part of the present invention, include a pair of mounting flanges 36 formed on housing 12 and a cover plate 38.
  • Other optional elements which do not form part of the present invention include jewels 40 (only jewel 40A is shown in FIG. 5) and 42 (only jewel 42A is shown in FIGS. 1, 2, and 4) which may be mounted in openings 30 and 34 respectively to further reduce friction between the wires and the guide plates. Since, as will be seen later, the print wires do not normally contact the walls of openings 34, a jewel would not normally be used inthese openings except for print head design to operate at extremely high speed.
  • a coating 44 of a synthetic grease of high viscosity FIGS. 1, 2, and 4
  • the length of wire between jewel 20 and guide plates 28 (L1 in FIG. 7), the length of wire between guide plates 28 and 32 (L2), and the length of wire between guide plate 32 and rear wall 14 (or the end of tube 45) (L3) must all be less than the critical length (L). This then is one criteria for selecting the positions of plates 28 and 32.
  • tubes 45 may be utilized to shorten the effective length of the wire.
  • the length of the wire L will be the effective length of the wire, the length of the wire projecting from tube 45.
  • plates 28 and 32 should also be placed at, or within at least a one-eighth wavelength of, the peak vibration points of the print wire when it is vibrating at its fundamental frequency. Since the print wires are restrained at their ends (or effective end), a print wire vibrating at its fundamental natural frequency would, at the peak points of its vibration, assume one of the two configurations shown in FIG. 9 (one configuration being shown solid and the other dotted). The stiffness of the wire is such that all but the fundamental vibrating frequency may be ignored. Thus, forward guide plate 28 should be positioned within the quarter wavelength section defined by darkened line 50 in FIG. 9, and rear guide plate 32 should be positioned within the quarter wavelength section defined by darkened line portion 52. In each instance, the plate should be placed as close to the peak vibration point as possible.
  • a starting point is the position of the opening 22 in jewel through which a given wire passes relative to the position of opening 22A.
  • the starting point for determining the position of each of the openings 30 is displaced from opening 30A by the same distance as the corresponding opening 22 is displaced from opening 22A (FIG. 5).
  • the starting points for determining the positions of openings 34 are similarly displaced as is shown in FIG. 4, as are the starting points for determining the positions of the openings 17 in wall 14.
  • the starting points for computations are the points which the wires 18 would pass through in the plates or wall if the wire projected back from jewel 20 undeflected and parallel to wire 18A.
  • This line, which passes through each of the starting points for the given wire 18, is the line 54 shown in FIG. 7.
  • a displacement S of the solenoid from the starting point defined by line 54 is first selected.
  • Solenoid assembly 168 is then positioned a distance S from the starting point for wire 18B and directly above the starting point.
  • the remaining solenoid assemblies are then positioned, as shown in FIG. 3, with each solenoid assembly a distance S from its corresponding starting point and angularly displaced from the adjacent solenoid assembly by (for a seven wire configuration, i.e. N 7).
  • X-axis 56 is a straight line between the opening 17 in wall 14 in which the solenoid assembly 16 is mounted or the end of tube 45 if tubes 45 are employed and the opening 22 in jewel 20 where the wire terminates.
  • X-axis 56 represents the undefiected condition of the wire 18.
  • a Y-axis is defined which is perpendicular to the X-axis 56.
  • the wire may be considered to be a beam supported at its ends, and known equations for such structures utilized.
  • E and I have previously been defined and are constants and S and L, have previously been selected.
  • the length a known, and the deflection yl known, r1 may be determined by either using the values a and y] to determine the length q for triangle 1, using standard geometry equations, and then use the known values q and L1 to compute r1 for triangle II, or by using the length a and the angle 3 to compute the length of side I, determine the length of side it by subtracting yl from t, and then use the value it and the angle B in triangle III to determine the length rl.
  • each opening 30 is determined, as may be seen in FIG. 5, by placing opening 308 a distance rl from the starting point for the B wire directly in line with and above the WuC WIN b hc-] Again, for purposes of the calculations, the displacement for openings 34 (FIG. 4) may be determined from deflection ⁇ '2 utilizing standard geometry equations in the same way that rl was determined from y 1. Once r2 is determined, it is utilized, as shown in FIG. 4, to determine the exact position for each of the openings 34 in the same manner previously indicated for determining the positions for the openings 30.
  • deflection yl and y2 are the natural deflections which occur when the wire is mounted and held at one end at the angle a and is mounted and held at the other end (the A end) parallel to the axis 54.
  • plate 32 is not required to apply any force to the print wires to cause deflection thereof.
  • the openings 34 being slightly larger than the print wires, would thus not normally contact the wires except on impact to prevent buckling of the wires and to damp vibration.
  • plate 32 Since buckling primarily occurs in the forward section of the wire, plate 32 is included primarily for damping vibration and the openings therein are large enough (being as indicated previously, several mills in diameter larger than the openings 30 in plate 28) so that there is little if any contact between the wires and the plate.
  • solenoid assembly angle and position, of guide plate positions, and of guide plate opening positions a print head has been provided which eliminates print wire buckling and vibration without requiring guide tubes and which provides very little friction between the print wires and the guide plates.
  • a wire matrix print head employing a plurality of print wires on which friction is reduced, although all or all but one of said print wires are bent between the printing and non-printing ends thereof, the use of guide tubes therebetween being eliminated, comprising a plurality of n print wires each having a printing and a nonprinting end thereon, said It print wires each having a positionally determined natural deflection with peak vibrating deflection points when vibrating at its natural frequency of vibration and a critical length L for a straight unsupported section thereof defined by where P critical buckling load E Youngs Modulus of Elasticity l moment of inertia,
  • a print guide member having a openings therein with a predetermined spacing between adjacent openings for supporting one of said print wires on said print end thereof which passes through each of said openings
  • first and second guide plates are spaced at predetermined positions between said means for mounting the non-printing ends of said wires and said print guide member, said predetermined positions being such that said first guide plate is spaced from said print guide member by a first predetermined distance, said first and second guide plates being spaced from each other by a second predetermined distance, and said second guide plate being spaced from said means for supporting the non-printing ends of the wires by a third predetermined distance, said first, second and third predetermined distances all being shorter than said critical length for each of said unsupported sections of said print wires to prevent the buckling of said sections of said print wires,
  • said first and second guide plates each having a center opening through which said one wire passes, and (-l) other openings positioned around the center opening through a separate one of which each of the other (nl) wires passes, the spacing of each of said openings from the corresponding center opening being a function of said natural deand wherein the natural deflection of the print wire at the position of the second guide plate is WuC from which the positions of the holes in the guide plates are determined.
  • a print head as claimed in claim 1 including a jewel mounted in each of the openings in at least one of said guide plates to reduce the friction on a wire passing therethrough.
  • a print head as claimed in claim 1 including a synthetic grease lubricant coated on at least one side of at least one of said guide plates and over the portions of the print wires adjacent thereto to reduce the friction between the guide plates and the wires.

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  • Impact Printers (AREA)
  • Character Spaces And Line Spaces In Printers (AREA)
US378774A 1973-07-12 1973-07-12 Matrix wire print head with free bending print wires Expired - Lifetime US3907092A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US378774A US3907092A (en) 1973-07-12 1973-07-12 Matrix wire print head with free bending print wires
GB2315974A GB1470534A (en) 1973-07-12 1974-05-23 Matrix wire print head
CA201,153A CA1010294A (en) 1973-07-12 1974-05-29 Matrix wire print head and method for the manufacture thereof
DE2430440A DE2430440A1 (de) 1973-07-12 1974-06-25 Nadelmatrix-druckkopf und verfahren zur herstellung eines nadelmatrix-druckkopfes
SE7408857A SE402497B (sv) 1973-07-12 1974-07-05 Tradskrivmatrishuvud
FR7424178A FR2236661A1 (sv) 1973-07-12 1974-07-11
JP49080093A JPS5037511A (sv) 1973-07-12 1974-07-12
IT25119/74A IT1017124B (it) 1973-07-12 1974-07-12 Testa di stampa con matrice a fili di tipo perfezionato

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US378774A US3907092A (en) 1973-07-12 1973-07-12 Matrix wire print head with free bending print wires

Publications (1)

Publication Number Publication Date
US3907092A true US3907092A (en) 1975-09-23

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ID=23494498

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Application Number Title Priority Date Filing Date
US378774A Expired - Lifetime US3907092A (en) 1973-07-12 1973-07-12 Matrix wire print head with free bending print wires

Country Status (8)

Country Link
US (1) US3907092A (sv)
JP (1) JPS5037511A (sv)
CA (1) CA1010294A (sv)
DE (1) DE2430440A1 (sv)
FR (1) FR2236661A1 (sv)
GB (1) GB1470534A (sv)
IT (1) IT1017124B (sv)
SE (1) SE402497B (sv)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4154541A (en) * 1977-06-13 1979-05-15 Ricoh Company, Ltd. Printer head assembly
US4211494A (en) * 1977-03-29 1980-07-08 Siemens Aktiengesellschaft Device for guiding the printer needles in a mosaic needle printer
US4278020A (en) * 1979-10-19 1981-07-14 International Business Machines Corporation Print wire actuator block assembly for printers
US4527469A (en) * 1983-04-15 1985-07-09 Dataproducts Corporation Dot matrix print actuator
US4832516A (en) * 1985-12-05 1989-05-23 Ncr Corporation Dot matrix print head
US5033884A (en) * 1988-08-29 1991-07-23 Oki Electric Industry Co., Ltd. Wire dot printer head with oil absorbing member
US5433538A (en) * 1992-07-27 1995-07-18 Fujitsu Limited Wire guide in a wire dot print head
US20080094428A1 (en) * 2006-10-20 2008-04-24 Hewlett-Packard Development Company Lp Fluid dispenser

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52151809U (sv) * 1976-05-14 1977-11-17
DE2649213C3 (de) * 1976-10-28 1982-01-21 Siemens AG, 1000 Berlin und 8000 München Anordnung von Magnetsystemen in einem Mosaik-Nadeldruckkopf
SE408034B (sv) * 1977-03-15 1979-05-14 Philips Svenska Ab Lageranordning vid ett mosaiktryckhuvud
GB2022515B (en) * 1978-05-12 1982-04-21 Suwa Seikosha Kk Head for a dot printer
JPS59229360A (ja) * 1984-04-27 1984-12-22 Matsushita Electric Ind Co Ltd 印字ヘツド
FR2698319B1 (fr) * 1992-11-24 1997-05-16 Microlys Spa Tete d'impression a impact pour l'impression de caracteres matriciels a barres magnetiques.

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3584575A (en) * 1968-11-12 1971-06-15 Johann Distl Mosaic printing head and device for producing the same
US3672482A (en) * 1970-08-31 1972-06-27 Ibm Wire matrix print head
US3690431A (en) * 1971-06-14 1972-09-12 Centronics Data Computer Print head assembly containing solenoids
US3782520A (en) * 1971-11-04 1974-01-01 Centronics Data Computer Resilient head assembly having resilient mount
US3795298A (en) * 1972-05-30 1974-03-05 An Control Inc Di Wire matrix print head particularly for high speed printers

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3802543A (en) * 1971-09-13 1974-04-09 Centronics Data Computer Jewel bearings for printer heads and the like

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3584575A (en) * 1968-11-12 1971-06-15 Johann Distl Mosaic printing head and device for producing the same
US3672482A (en) * 1970-08-31 1972-06-27 Ibm Wire matrix print head
US3690431A (en) * 1971-06-14 1972-09-12 Centronics Data Computer Print head assembly containing solenoids
US3782520A (en) * 1971-11-04 1974-01-01 Centronics Data Computer Resilient head assembly having resilient mount
US3795298A (en) * 1972-05-30 1974-03-05 An Control Inc Di Wire matrix print head particularly for high speed printers

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4211494A (en) * 1977-03-29 1980-07-08 Siemens Aktiengesellschaft Device for guiding the printer needles in a mosaic needle printer
US4154541A (en) * 1977-06-13 1979-05-15 Ricoh Company, Ltd. Printer head assembly
US4278020A (en) * 1979-10-19 1981-07-14 International Business Machines Corporation Print wire actuator block assembly for printers
US4527469A (en) * 1983-04-15 1985-07-09 Dataproducts Corporation Dot matrix print actuator
US4832516A (en) * 1985-12-05 1989-05-23 Ncr Corporation Dot matrix print head
US5033884A (en) * 1988-08-29 1991-07-23 Oki Electric Industry Co., Ltd. Wire dot printer head with oil absorbing member
US5433538A (en) * 1992-07-27 1995-07-18 Fujitsu Limited Wire guide in a wire dot print head
US20080094428A1 (en) * 2006-10-20 2008-04-24 Hewlett-Packard Development Company Lp Fluid dispenser
US8733274B2 (en) * 2006-10-20 2014-05-27 Hewlett-Packard Development Company, L.P. Tube mounted inkjet printhead die

Also Published As

Publication number Publication date
CA1010294A (en) 1977-05-17
DE2430440A1 (de) 1975-02-06
SE7408857L (sv) 1975-01-13
JPS5037511A (sv) 1975-04-08
GB1470534A (en) 1977-04-14
SE402497B (sv) 1978-07-03
FR2236661A1 (sv) 1975-02-07
IT1017124B (it) 1977-07-20

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AS Assignment

Owner name: ALLIED CORPORATION COLUMBIA ROAD AND PARK AVENUE,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BUNKER RAMO CORPORATION A CORP. OF DE;REEL/FRAME:004149/0365

Effective date: 19820922