US3518745A - Installation tool - Google Patents
Installation tool Download PDFInfo
- Publication number
- US3518745A US3518745A US693927A US3518745DA US3518745A US 3518745 A US3518745 A US 3518745A US 693927 A US693927 A US 693927A US 3518745D A US3518745D A US 3518745DA US 3518745 A US3518745 A US 3518745A
- Authority
- US
- United States
- Prior art keywords
- nut
- plate
- tool
- pins
- rivets
- 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
- 238000009434 installation Methods 0.000 title description 8
- 238000007689 inspection Methods 0.000 description 5
- 238000010276 construction Methods 0.000 description 4
- 230000000994 depressogenic effect Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000002184 metal Substances 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 239000000463 material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P19/00—Machines for simply fitting together or separating metal parts or objects, or metal and non-metal parts, whether or not involving some deformation; Tools or devices therefor so far as not provided for in other classes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P2700/00—Indexing scheme relating to the articles being treated, e.g. manufactured, repaired, assembled, connected or other operations covered in the subgroups
- B23P2700/01—Aircraft parts
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49908—Joining by deforming
- Y10T29/49915—Overedge assembling of seated part
- Y10T29/4992—Overedge assembling of seated part by flaring inserted cup or tube end
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49908—Joining by deforming
- Y10T29/49938—Radially expanding part in cavity, aperture, or hollow body
- Y10T29/49943—Riveting
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/53—Means to assemble or disassemble
- Y10T29/53709—Overedge assembling means
- Y10T29/5377—Riveter
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/53—Means to assemble or disassemble
- Y10T29/53909—Means comprising hand manipulatable tool
- Y10T29/53913—Aligner or center
Definitions
- the tool includes a body portion and one or more pins, the latter being resiliently mounted in the body portion and normally have a projecting relation with respect to a face of the body portion.
- the face and projecting pins provide means for positioning a nut-plate and other associated components in troublesome, hard to reach, locations.
- the tool also provides means for locating a nut-plate in previously prepared holes and subsequently facilitates securing the same utilizing blind-type rivets.
- Nut-plates and similar devices are extensively utilized to secure inspection plates and the like on various types of structures.
- nut-plates are extensively used in all situations where a plate or cover (inspection plate) must be removed and replaced numerous times, and a flush relationship preserved between the plate and surrounding structure. The foregoing is especially true in the airframe industry where nut-plates have acquired extensive use for this purpose.
- the present invention pertains to a tool functioning to locate, position and retain a nut-plate and associated components in position while a riveting operation, securing a nut-plate to supporting structure, is effected.
- the tool includes a body in which one or more pins are resiliently mounted.
- the pins provide means on which a nut-plate and associated components may be placed in their proper relation, the pins are then urged through previously prepared apertures and so retained by the tool disclosed herein.
- Hollow rivets are utilized in securing the nut-plate to supporting structure, the rivets being urged into the apertures presently occupied by the pins. This is made possible by the pins being depressed into the body of the tool.
- the rivets occupy the space previously occupied by the pins.
- the shank thereof is expanded in a manner well known to those skilled in the art.
- an inspection plate is now secured in a conventional manner utilizing the nut-plate for this purpose.
- the inspection plate becomes a component of the aircraft and has a flush relationship with surrounding skin.
- An object of the present invention is to provide a tool facilitating the positioning and retaining of a nut-plate or the like and associated components while the nutplate is secured to supporting structure.
- Another object is to provide a tool including a body having one or more pins resiliently mounted therein and in which the pins are depressed in the body and replaced by rivets permanently securing the nut-plate to supporting structure.
- FIG. 1 constitutes a side view of a tool of the type disclosed herein; portions of the tool being broken away to better show the construction thereof.
- FIG. 2 is a side view of the tool shown in FIG. 1.
- FIGS. 3 and 4 are fragmentary side views of the tool of FIGS. 1 and 2 showing the tool being utilized to locate and install a nut-plate.
- the tool 11 includes a body portion 12 having one or more pins 14 mounted in the body portion.
- the tool 11 is utilized to install a nut-plate and for this reason a pair of spaced pins 14 is shown in the body 12.
- the portion 12 is shown as being constructed of metal, it, however, may be constructed of plastic or other formable material.
- the pins 14 are normally constructed of metal.
- the pins 14 are resiliently mounted in the portion 12 for longitudinal movement and functions in a manner that will become apparent as the disclosure progresses.
- a spirally wound spring 16 is positioned in the bores 17; the springs acting to urge the pins to their extended position shown in FIGS. 1 and 2.
- the lower end of the pins 14 are enlarged as indicated by the numeral 18 and retained in the bores 17 by retainer means 19.
- the enlarged end of the pins 14 maintains their alignment with the apertures in the retainers 19 and also provides contacting means for the springs 16.
- the upper portions of the retainers 19 have a flush relation with the upper surface 21 of the body 12. In other words, the surface constitutes a plane fiat surface. Construction of the portion 12 is completed in that a recess 22 of a size and shape adapted to receive the body portion of a nut plate 23 (FIGS. 3 and 4).
- a nut-plate for example the nut-plate 23, is positioned on the surface 21 with the pins extending through apertures provided therein and with the body portion thereof received in the recess 22 substantially as shown in FIGS. 3 and 4.
- One or more spacers may also be positioned on the pins 14 of the nut-plate if required.
- the tool 11, with the nut-plate 23 and spacers (if required) positioned thereon are now positioned below supporting structure 24 with the pins 14 extending through previously prepared apertures 26 provided in the structure 24 substantially as shown in FIGS. 3 and 4.
- the nut-plate is now secured to the structure 24 by means of hollow rivets by expanding the shanks thereof in a manner that is well known in the art.
- One shank of the rivets (right rivet) has been expanded in FIG. 3 securing the nut-plate 23 to the structure 24.
- FIG. 3 also shows the operation in which the shank of the other rivet (left rivet) is expanded and how the tool 11 functions and cooperates during this operation.
- a riveting tool 28 containing a plurality of hollow type rivets 29 is utilized. Prior to an expansion operation, one of the rivets 29 has been ejected from the tool 28, assuming a position directly below the jaws of the tool 28, and is thus supported by the mandrel 27 of the tool 28.
- FIG. 4 the installation of the nut-plate is completed and the pins 14 have returned to their extended position.
- countersunk rivets 29 are utilized in securing the nutplate 23 to the structure 24 and, therefore, allows an inspection plate to be installed (secured) having an intimate contacting relation with the structure 24 and a flush relation with surrounding structure.
- a hand tool for installing nut plates and the like in blind or fairly inaccessible locations comprising:
- said body portion including end portions and said body portion having a substantially rectangular configuration in lateral and longitudinal cross-section;
- (g) means normally urging said pin members a predetermined distance above said first end surface and allowing said pin members to be depressed a predetermined distance within said body portion at such times as said pin members are acted upon by longitudinal forces;
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Connection Of Plates (AREA)
Description
July 7, 1970 w, Y ETAL 3,518,745
INSTALLATION TOOL Filed Dec. 27, 1967 uwmmw max- United States Patent 3,518,745 INSTALLATION TOOL J. W. Gray, Norwalk, and Carl T. Hoifman, Palos Verdes Estates, Calif., assignors to Northrop Corporation, Beverly Hills, Calif., a corporation of California Filed Dec. 27, 1967, Ser. No. 693,927 Int. Cl. B25b 27/14 US. Cl. 29-271 2 Claims ABSTRACT OF THE DISCLOSURE A tool facilitating the installation of nut-plates and the like in which one or more rivets, bolts or the like are utilized to effect the installation. The tool includes a body portion and one or more pins, the latter being resiliently mounted in the body portion and normally have a projecting relation with respect to a face of the body portion. The face and projecting pins provide means for positioning a nut-plate and other associated components in troublesome, hard to reach, locations. The tool also provides means for locating a nut-plate in previously prepared holes and subsequently facilitates securing the same utilizing blind-type rivets.
Nut-plates and similar devices are extensively utilized to secure inspection plates and the like on various types of structures. In fact, nut-plates are extensively used in all situations where a plate or cover (inspection plate) must be removed and replaced numerous times, and a flush relationship preserved between the plate and surrounding structure. The foregoing is especially true in the airframe industry where nut-plates have acquired extensive use for this purpose.
Briefly, the present invention pertains to a tool functioning to locate, position and retain a nut-plate and associated components in position while a riveting operation, securing a nut-plate to supporting structure, is effected. Specifically, the tool includes a body in which one or more pins are resiliently mounted. The pins provide means on which a nut-plate and associated components may be placed in their proper relation, the pins are then urged through previously prepared apertures and so retained by the tool disclosed herein. Hollow rivets are utilized in securing the nut-plate to supporting structure, the rivets being urged into the apertures presently occupied by the pins. This is made possible by the pins being depressed into the body of the tool. In other words, the rivets occupy the space previously occupied by the pins. After the rivets are firmly seated, the shank thereof is expanded in a manner well known to those skilled in the art. Thus the nut-plate or plates are secured to supporting structure and an inspection plate is now secured in a conventional manner utilizing the nut-plate for this purpose. Thus, it will be seen that the inspection plate becomes a component of the aircraft and has a flush relationship with surrounding skin.
An object of the present invention is to provide a tool facilitating the positioning and retaining of a nut-plate or the like and associated components while the nutplate is secured to supporting structure.
Another object is to provide a tool including a body having one or more pins resiliently mounted therein and in which the pins are depressed in the body and replaced by rivets permanently securing the nut-plate to supporting structure.
Although the characteristic features of the present invention are particularly pointed out in the appended claims, the invention itself, also the manner in which it may be carried out, will be better understood by referring to the following description taken in connection with 3,518,745 Patented July 7, 1970 the accompanying drawings forming a part of this application and in which:
FIG. 1 constitutes a side view of a tool of the type disclosed herein; portions of the tool being broken away to better show the construction thereof.
FIG. 2 is a side view of the tool shown in FIG. 1.
FIGS. 3 and 4 are fragmentary side views of the tool of FIGS. 1 and 2 showing the tool being utilized to locate and install a nut-plate.
Referring to the drawing, a tool 11, as disclosed herein, is shown in FIGS. 2 and 3. The tool 11 includes a body portion 12 having one or more pins 14 mounted in the body portion. In the present embodiment the tool 11 is utilized to install a nut-plate and for this reason a pair of spaced pins 14 is shown in the body 12. In the present embodiment the portion 12 is shown as being constructed of metal, it, however, may be constructed of plastic or other formable material. The pins 14 are normally constructed of metal.
The pins 14 are resiliently mounted in the portion 12 for longitudinal movement and functions in a manner that will become apparent as the disclosure progresses. To accomplish the resilient mounting of the pins 14 a spirally wound spring 16 is positioned in the bores 17; the springs acting to urge the pins to their extended position shown in FIGS. 1 and 2. The lower end of the pins 14 are enlarged as indicated by the numeral 18 and retained in the bores 17 by retainer means 19. The enlarged end of the pins 14 maintains their alignment with the apertures in the retainers 19 and also provides contacting means for the springs 16. The upper portions of the retainers 19 have a flush relation with the upper surface 21 of the body 12. In other words, the surface constitutes a plane fiat surface. Construction of the portion 12 is completed in that a recess 22 of a size and shape adapted to receive the body portion of a nut plate 23 (FIGS. 3 and 4).
Construction and relation of the components comprising the tool 11 having been described, a better understanding thereof will be forthcoming from the following discussion of its use and operation during the installation of a nut-plate.
A nut-plate, for example the nut-plate 23, is positioned on the surface 21 with the pins extending through apertures provided therein and with the body portion thereof received in the recess 22 substantially as shown in FIGS. 3 and 4. One or more spacers (not shown) may also be positioned on the pins 14 of the nut-plate if required.
The tool 11, with the nut-plate 23 and spacers (if required) positioned thereon are now positioned below supporting structure 24 with the pins 14 extending through previously prepared apertures 26 provided in the structure 24 substantially as shown in FIGS. 3 and 4.
The nut-plate is now secured to the structure 24 by means of hollow rivets by expanding the shanks thereof in a manner that is well known in the art. One shank of the rivets (right rivet) has been expanded in FIG. 3 securing the nut-plate 23 to the structure 24. FIG. 3 also shows the operation in which the shank of the other rivet (left rivet) is expanded and how the tool 11 functions and cooperates during this operation.
To effect the above operation, a riveting tool 28 containing a plurality of hollow type rivets 29 is utilized. Prior to an expansion operation, one of the rivets 29 has been ejected from the tool 28, assuming a position directly below the jaws of the tool 28, and is thus supported by the mandrel 27 of the tool 28.
The mandrel 27, with rivet 29 mounted thereon, is now utilized to depress the pin 14. As the pin 14 is depressed it will be apparent that the aperture, previously occupied by the pin 14, will now be occupied by the rivet 29 and the mandrel 27 as shown in FIG. 3. Thus the relative position of the nut-plate 23 with respect to the aperture 31 is maintained during the installation of the nut-plate 23.
In FIG. 4 the installation of the nut-plate is completed and the pins 14 have returned to their extended position. By referring further to FIG. 4 it will be noted that countersunk rivets 29 are utilized in securing the nutplate 23 to the structure 24 and, therefore, allows an inspection plate to be installed (secured) having an intimate contacting relation with the structure 24 and a flush relation with surrounding structure.
While in order to comply with the statute, the inven tion has been described in language more Or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed cornprise the preferred form of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.
What is claimed is:
l. A hand tool for installing nut plates and the like in blind or fairly inaccessible locations, comprising:
(a) an elongated body portion of a size to be held and manipulated in one hand;
(b) said body portion including end portions and said body portion having a substantially rectangular configuration in lateral and longitudinal cross-section;
(c) one of said end portions defining a first end surface major portions of which are located in a fiat reference plane;
((1) said one end portion including a recess of cylindrical configuration opening on said first end surface;
(e) a pair of bores in said body portion opening on said first end surface the axes of which have a parallel relation and are located equal distances on each side of said recess;
(f) a pin member of cylindrical configuration mounted in each of said bores;
(g) means normally urging said pin members a predetermined distance above said first end surface and allowing said pin members to be depressed a predetermined distance within said body portion at such times as said pin members are acted upon by longitudinal forces;
(h) and said pin members, recess and first end surface providing means on which a nut plate may be positioned and temporarily located with respect to supporting structure in that said pin members are received in apertures provided in the nut plate and the barrel portion thereof received in said recess thereby enabling the nut plate to be positioned and subsequently secured to the supporting structure.
2. A hand tool as set forth in claim 1:
(a) in which said means normally urging said pin members a predetermined distance above said first end surface constitutes helical spring positioned in each of said bores below said pin members.
References Cited UNITED STATES PATENTS 593,879 11/1897 DuBrul 2693 10 892,305 6/1908 Raiche 144-32 1,225,265 5/1917 Miller 29-271 2,167,189 7/ 1939 Verderber 33181 2,521,505 9/1950 Doyle 33l81 FOREIGN PATENTS 71,030 1893 Germany.
ROBERT C. RIORDON, Primary Examiner G. F. GRAFEL, Assistant Examiner US. Cl. X.R. 29243.53
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US69392767A | 1967-12-27 | 1967-12-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3518745A true US3518745A (en) | 1970-07-07 |
Family
ID=24786704
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US693927A Expired - Lifetime US3518745A (en) | 1967-12-27 | 1967-12-27 | Installation tool |
Country Status (1)
Country | Link |
---|---|
US (1) | US3518745A (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3729801A (en) * | 1970-06-18 | 1973-05-01 | Rohr Industries Inc | Nutplate riveting device and method |
US3802053A (en) * | 1970-08-03 | 1974-04-09 | Rohr Industries Inc | Nutplate riveting attachment device |
US3802060A (en) * | 1970-08-03 | 1974-04-09 | Rohr Industries Inc | Nutplate riveting device and method |
US4212098A (en) * | 1977-12-05 | 1980-07-15 | Eltra Corporation | Method and apparatus for aligning a bearing |
US4646419A (en) * | 1986-04-14 | 1987-03-03 | At&T | Method for engaging a substrate |
US4729551A (en) * | 1986-04-14 | 1988-03-08 | American Telephone And Telegraph Company | Apparatus for engaging a substrate |
US5003568A (en) * | 1988-08-25 | 1991-03-26 | Spezialmaschinenbau Steffel Gmbh & Co. Kg | Omni-directional X-ray tube |
US20140208573A1 (en) * | 2013-01-29 | 2014-07-31 | Sikorsky Aircraft Corporation | Riveting tool |
US20150123333A1 (en) * | 2013-11-06 | 2015-05-07 | Fu Tai Hua Industry (Shenzhen) Co., Ltd. | Positioning device |
US11707790B2 (en) * | 2020-02-08 | 2023-07-25 | Jr Automation Technologies, Llc | Rivet fastener apparatus |
-
1967
- 1967-12-27 US US693927A patent/US3518745A/en not_active Expired - Lifetime
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3729801A (en) * | 1970-06-18 | 1973-05-01 | Rohr Industries Inc | Nutplate riveting device and method |
US3802053A (en) * | 1970-08-03 | 1974-04-09 | Rohr Industries Inc | Nutplate riveting attachment device |
US3802060A (en) * | 1970-08-03 | 1974-04-09 | Rohr Industries Inc | Nutplate riveting device and method |
US4212098A (en) * | 1977-12-05 | 1980-07-15 | Eltra Corporation | Method and apparatus for aligning a bearing |
US4646419A (en) * | 1986-04-14 | 1987-03-03 | At&T | Method for engaging a substrate |
US4729551A (en) * | 1986-04-14 | 1988-03-08 | American Telephone And Telegraph Company | Apparatus for engaging a substrate |
US5003568A (en) * | 1988-08-25 | 1991-03-26 | Spezialmaschinenbau Steffel Gmbh & Co. Kg | Omni-directional X-ray tube |
US20140208573A1 (en) * | 2013-01-29 | 2014-07-31 | Sikorsky Aircraft Corporation | Riveting tool |
US9616487B2 (en) * | 2013-01-29 | 2017-04-11 | Sikorsky Aircraft Corporation | Riveting tool |
US20150123333A1 (en) * | 2013-11-06 | 2015-05-07 | Fu Tai Hua Industry (Shenzhen) Co., Ltd. | Positioning device |
US9475162B2 (en) * | 2013-11-06 | 2016-10-25 | Fu Tai Hua Industry (Shenzhen) Co., Ltd. | Positioning device |
US11707790B2 (en) * | 2020-02-08 | 2023-07-25 | Jr Automation Technologies, Llc | Rivet fastener apparatus |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3518745A (en) | Installation tool | |
US2373083A (en) | Fastening device | |
US2616328A (en) | Fastener | |
US3146010A (en) | Readily demountable pawl latch | |
US2767877A (en) | Rivet adapted to secure two sheets in spaced relationship | |
TWM515040U (en) | Resilience fastener | |
US3138188A (en) | Retainer ring adapted to be snapped through the workpiece aperture | |
US2570618A (en) | Nut and plate temporary fastener | |
US5046707A (en) | Spherical positioning pin | |
TW201809487A (en) | Fixing device achieving effects of surely located and rapid dismounting and mounting | |
US3511525A (en) | Connecting device for fastening together two thin plates in relative perpendicular positions | |
US3438302A (en) | Removable blind rivet | |
US2696765A (en) | Fixture key | |
US2478972A (en) | Cowl fastener stud | |
US4026341A (en) | Two-part nut | |
US3103845A (en) | Demountable retainer for punch and die sets | |
US2348116A (en) | Device for positioning and aligning apertures | |
US2092653A (en) | Transferring location | |
US3442112A (en) | Rivet bucker assembly | |
US2910271A (en) | Wrecking bar | |
US2920509A (en) | Drill bushing and jig | |
US2941303A (en) | Universal locating fixture | |
US2350436A (en) | Perforating device | |
US2398644A (en) | Temporary positioning and holding means for apertured members | |
US2424309A (en) | Temporary holding pin |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: NORTHROP CORPORATION, A DEL. CORP. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:NORTHROP CORPORATION, A CA. CORP.;REEL/FRAME:004634/0284 Effective date: 19860516 |