An alignment and mounting apparatus for mounting two modules (10,12) includes a first portion having a cylindrical alignment pin (16) projecting normal to a module surface, a second portion having a three-stage alignment guide (18) including a shoehorn flange (34), a Y-slot (42) and a V-block (22) which sequentially guide the alignment pin (16) with successively finer precision and a third portion in the form of a spring-loaded captive fastener (20) for connecting the two modules after alignment is achieved

Preston, Dennis R.

NASA Technical Reports Server

I11111 1l1111111111111 lllll Il11 lllll Il11 Il11 11111 ll111111ll11111111111 
US005253944A 
United States Patent [191 [ i l l  Patent Number: 5,253,944 
Preston 1451 Date of Patent: Oct. 19, 1993 
[54] PRECISION ALIGNMEW AND MOUNTING 
[75] Inventor: Dennis R. Preston, Brookfield, Conn. 
[73] Assignee: Hughes Aircraft Company, Los 
[21] Appl. No.: 748,587 
(221 Filed: Aug. 22, 1991 
[51] Int. C l . 5  .............................................. F16B 21/00 
[52f U.S. Cl. ........................................ 43/13; 403/24; 
403/337; 403/408.1; 244/158 R, 244/161; 
24/54; 41 1/386; 411/107; 411/353; 41 1/999 
[58] Field of Search .................. 403/13, 14, 24, 408.1, 
403/337; 244/158 R, 161, 54; 411/386, 353, 
352, 107, 108, 113, 970, 999; 439/374, 66, 
APPARATUS 
Angeles, Calif. 
73-74, 330, 350 
1561 References Cited 
U.S. PATENT DOCUMENTS 
3,343,581 9/1967 Martin et al. ................... 411/999 X 
3,608,848 9/1971 Cantor et al. ....................... 244/161 
4,508,296 4/1985 Clark ................................. 403/76 X 
4,607,815 8/1986 Turci et al. ......................... 244/161 
5,040,748 8/1991 Torre et al. ......................... 244/161 
FOREIGN PATENT DOCUMENTS 
2182295 5/1987 United Kingdom ............ 244/158 R 
Primary Examiner-Randolph A. Reese 
Assistant Examiner-Harry C. Kim 
Attorney, Agent, or Firm-Michael W. Sales; Wanda K. 
Denson-Low 
[571 ABSTRACT 
An alignment and mounting apparatus for mounting 
two modules (10,12) includes a first portion having a 
cylindrical alignment pin (16) projecting normal to a 
module surface, a second portion having a three-stage 
alignment guide (18) including a shoehorn flange (N), a 
Y-slot (42) and a V-block (22) which sequentially guide 
the alignment pin (16) with successively finer precision 
and a third portion in the form of a spring-loaded cap- 
tive fastener (20) for connecting the two modules after 
alignment is achieved. 
11 Claims, 2 Drawing Sheets 
https://ntrs.nasa.gov/search.jsp?R=20080004255 2019-08-30T02:15:59+00:00Z
U.S. Patent Oct. 19, 1993 Sheet 1 of 2 5,253,944 
Fig.  2 .  
U.S. Patent Oct. 19, 1993 Sheet 2 of 2 5,253,944 
26 
Fig. 3. 
Fig. 4. 
F ig .  5. 
16 22 
5.25 3,944 
PRECISION ALIGNMENT AND MOUNTING 
APPARATUS 
The invention described herein was made in the per- 
formance of work under NASA Contract Number 
NAS9-18200 and is subject to the provisions of Section 
305 of the National Aeronautics and Space Act of 1958 
(72 Stat. 435; 42 U.S.C. 2457). 
BACKGROUND O F  THE INVENTION 
1. Field of the Invention 
The present invention relates to a precision alignment 
and mounting apparatus and more particularly to a 
device for rapid alignment which includes three stages 
of increasingly finer guides for aligning two modules 
for connection. 
2. Description of the Prior Art 
There are many instances where components or mod- 
ules must be aligned and mounted together in a precise 
manner. In many such instances the alignment and 
mounting need not be rapidly accomplished and can be 
performed in a controlled environment. However, there 
are other situations where rapid alignment and mount- 
ing is an absolute necessity and where the environment 
is adverse. 
An example of such a situation that requires rapid 
precision alignment and mounting may be found in 
space equipment where components mounted to the 
equipment must be periodically replaced. Such compo- 
nents are known as orbit replaceable units (ORUs), all 
ORUs require rapid, low effort alignment procedures 
that are compatible with the capabilities of a suited 
astronaut or a telerobot. 
Heretofore such alignment systems simply used edge 
guide techniques which did not provide precise control 
of the position in all three axes. Such prior art devices 
utilized alignment guides that were single stage and did 
not provide a high degree of precision. Examples of 
alignment guides are found in Design For On-orbit 
Spacecraft Servicing, DFOSS Handbook, February, 
1990, (draft version) and Satellite Services Handbook 
Interface Guidelines LMSC/NASA, Feb. 23, 1983. 
SUMMARY OF THE INVENTION 
The present invention contemplates a precision align- 
ment and mounting apparatus which provides for con- 
trolled alignment of modules in sequential steps of in- 
creasingly finer precision. The apparatus allows two 
modules to be mounted with little visual aid or tactile 
feedback to the person or apparatus performing the 
alignment. The apparatus is a compact, weight efficient 
device consisting of two mating halves, one half essen- 
tially being a cylindrical pin projecting normal to a 
module body and the other half comprising a three- 
stage alignment system including a shoehorn flange, a 
Y-slot and a V-block which in turn guide and align the 
pin with successively finer precision. A spring-loaded 
captive fastener is associated with one module and is 
adapted to be screwed into a threaded opening in the 
other module after alignment has been achieved. 
2 
Another objective of the present invention is to pro- 
vide an alignment apparatus that requires little visual 
aid or tactile feedback. 
Another objective of the present invention is to pro- 
5 vide an alignment apparatus that is both compact and 
lightweight. 
DESCRIPTION OF THE DRAWINGS 
FIG. 1 is an isometric view illustrating how two 
10 modules may be aligned utilizing the apparatus of the 
present invention. 
FIG. 2 is an isometric view illustrating in greater 
detail the finest alignment guide and the mounting 
means of the present invention. 
FIG. 3 is a top view showing the components of the 
alignment apparatus of the present invention in their 
mounted position. 
FIG. 4 is a right side view of the alignment apparatus 
of FIG. 3. 
FIG. 5 is a partial vertical section of a front view of 
the alignment apparatus of FIG. 3. 
DETAILED DESCRIPTION OF THE PRESENT 
INVENTION 
FIG. 1 shows how the present invention may be 
utilized to attach two modules or, in particular, how a 
star tracker module 10 in the form of an ORU may be 
mounted to a space station 12. The ORU 10 is mounted 
to the station 12 using three alignment and mounting 
3 0  apparatus 14 constructed in accordance with the pres- 
ent invention. Each apparatus 14 comprises a first por- 
tion in the form of a cylindrical pin 16, a second portion 
in the form of a three-stage alignment guide 18 and a 
third portion in the form of an attachment means 20. 
Referring to FIG. 2, there is shown in greater detail 
the two halves of the present invention. The pin 16 is 
cylindrical with a spherical end and may have a diame- 
ter of one half inch as an example. The pin is mounted 
normal to a surface of the ORU 10. The three-stage 
40 alignment guide 18 includes as a final stage a V-groove 
22, which is precision formed in a mounting block 24, 
which is precisely located on the station 12. The V- 
groove 22 is adapted to receive pin 16 and to precisely 
align the pin within the groove. 
The attachment means 20 may be in the form of a 
spring-loaded captive fastener mounted in the ORU 10 
adjacent to the pin 16. The spring-loaded captive fas- 
tener may be selected from many commercially avail- 
able devices. A satisfactory device may be obtained 
5 0  from Rexnord of Torrance, Calif. The spring-loaded 
captive fastener may include a hexhead 26 with a 
threaded shaft 28 and an integral guidepoint 30. The 
fastener is spring loaded so that it is retracted within the 
ORU 10 so that the guidepoint 30 does not protrude 
55 beyond a surface of the ORU. Such protrusion could 
interfere with the alignment process. After the pin 16 is 
aligned in the groove 22 of the alignment apparatus, the 
spring-loaded captive fastener is activated so that the 
guidepoint 30 first extends into a threaded opening 32 to 
60 guide the threaded shaft 28 so that it may be screwed 
into the block 24. 
Referring to FIGS. 3, 4 and 5, there is shown in 
greater detail the three-stage alignment guide 18 of the 
15 
20 
25 
35 
45  
- 
A primary objective of the present invention is to 
provide a precision alignment apparatus. 
Another objective of the present invention is to pro- 
vide an alignment apparatus having sequentially finer 
alignment guides. 
present invention which comprises a shoehorn flange 
65 34, which is aligned to block 24 using alignment pins 36 
and mounting bolts 38. The shoehorn flange 34 func- 
tions as a first-stage-course alignment guide for engag- 
ing pin 16 and essentially funneling the pin to an exit 
5,253,944 
3 4 
opening 40 of the shoehorn flange. The opening 40 leads towards an exit opening, a Y-slot formed at the 
into a Y-slot 42 which functions as a second-alignment opening of the shoehorn flange for reducing allow- 
stage for guiding the pin 16 into the V-groove 22. able alignment pin motion and a block having a 
Thus, in the first stage the shoehorn flange 34 pro- V-groove juxtaposed with the Y-slot for providing 
vides a broad capture range for the alignment pin 16 as 5 a seated alignment for the alignment pin; and 
the pin enters the funnel-shaped shoehorn 34. As the fastening means for mounting said first and second 
alignment pin 16 is funneled into the shoehorn, the pin modules together. 
enters the Y-slot 42, thereby reducing the allowable 2. An alignment and mounting apparatus as described 
lateral motion and further directs the pin to the final 
alignment stage, namely, the V-groove 22 in which the 10 a spring-loaded captive fastener mounted to said first 
pin is finally seated. When the pin is seated into the 
V-groove, all clearance is eliminated and the pin is means associated with said second module for engag- 
fastened to the block 24 by the spring-loaded captive 
fastener 20, which has its threaded shaft 28 threadedly 3. An alignment and mounting apparatus as described 
engaged in the opening 32. Referring to FIG. 5 there is 15 in claim 2, wherein the spring-loaded captive fastener 
shown a clearance 46 between the ORU surface and the comprises a threaded shaft having a guidepin formed at 
mounting block to ensure that the pin 16 seats firmly in an end thereof; and 
the V-groove 22. said engaging means comprises a threaded opening 
In order to prevent any shifting of ORU 10, when one 
pin 16 may be aligned in groove 22 while the other pins 20 4. An alignment and mounting apparatus as described 
are still being aligned, each pin 16 is provided with an 
upstanding fin 44, which prevents the pin 16 from slip- a cylindrical member; and 
ping under the opening 40 of the shoehorn flange 34. a fin radially extending from said pin along a portion 
The fin 44 is also useful during a removal operation to of the length thereof. 
be certain that the pin freely slides out of the opening of 25 5. An alignment and mounting apparatus as described 
the shoehorn flange when the ORU is being removed. in claim 4, wherein the alignment pin terminate with a 
The shoehorn flange 34 may be simply formed from a spherical end and the fin extends to the most distal 
sheet metal component and is thus quite inexpensive and portion of said pin. 
easy to manufacture. The spring-loaded captive fastener 6. An alignment and mounting apparatus for aligning 
is a commercial product that is readily available. The 30 and mounting together first and second modules in a 
mounting block 24 with its V-groove 22 and the pin 16 
must be precisely machined using standard manufactur- at least three alignment pins mounted in a triangle 
ing techniques. orientation on said first module; 
Thus, the present invention provides a precision at least three-stage alignment means mounted to said 
alignment and mounting apparatus that is rugged, light- 35 second module in corresponding relation to the 
weight and extremely easy to use. The apparatus allows alignment pins mounted to said first module for 
for precision alignment and mounting with little visual guiding and aligning said alignment pins to the 
aid or tactile feedback and thus may be accomplished by desired orientation, said three-stage alignment 
a suited astronaut or telerobot. means having three alignment elements each pro- 
viding finer alignment precision including a shoe- 
associated with each alignment guide which is preferred horn flange providing a broad capture range for 
for secure mounting; however, it is possible to practice the alignment pin, said shoehorn flange having a 
the invention with a lesser number of fasteners which funnel shape for funneling the pin towards an exit 
need not be associated with the alignment guides. De- opening, a Y-slot formed at the opening of the 
pending on the configuration of the ORU, a single fas- 45 shoehorn flange for reducing allowable alignment 
tener could be centrally located to securely hold the pin motion and a block having a V-groove juxta- 
modules together. The fastener has been described as a posed with the Y-slot for providing a seated align- 
threaded fastener; however, other types of fasteners ment for the alignment pin; and 
could be used, such as pinch-type spring clips, magnets, fastening means for mounting said first and second 
or even gravity itself for earth-based applications 50 modules together. 
The present invention, while being particularly useful 7. An alignment and mounting apparatus as described 
for the mounting of ORUs to space equipment, is 
equally adaptable for fulfilling down-to-earth alignment a spring-loaded captive fastener mounted to said first 
and mounting needs where rapid precision alignment is module; and 
required. 55 means associated with said second module for engag- 
ing with said spring-loaded captive fastener. 
8.  An alignment and mounting apparatus as described 
in claim 7, wherein the spring-loaded captive fastener 
comprises a threaded shaft having a guidepin formed at 
said engaging means comprises a threaded opening 
for receiving the guidepin and threaded shaft. 
9. An alignment and mounting apparatus as described 
in claim 6, having a fastening means associated with 
10. An alignment and mounting apparatus as de- 
scribed in claim 6, wherein each alignment pin com- 
prises: 
in claim 1, wherein the fastening means comprises: 
module; and 
ing with said spring-loaded captive fastener. 
for receiving the guidepin and threaded shaft. 
in claim 1, wherein the alignment pin comprises: 
desired orientation, comprising: 
The invention has been described with a fastener 40 
in claim 6, wherein the fastening means comprises: 
What is claimed is: 
1. An alignment and mounting apparatus for aligning 
and mounting together first and second modules in a 
desired alignment position, comprising: 
an alignment pin mounted to said first module; 
a three-stage alignment means mounted to said sec- 
ond module for guiding and aligning said alignment 
pin to the desired alignment position, said three- 
stage alignment means having three alignment ele- 
ments each providing finer alignment precision 65 each alignment pin. 
including a shoehorn flange providing a broad 
capture range for the alignment pin, said shoehorn 
flange having a funnel shape for funneling the pin 
60 an end thereof; and 
5 
5,25 3,944 
6 
a cylindrical member; and 
a fin radially extending from said pin along a portion 
of the length thereof. 
11. An alignment and mounting apparatus as de- 
scribed in claim 10, wherein each alignment pin termi- 
nates with a spherical end and the fin extends to the 
most distal portion of said pin. * * * * *  
5 
20 
25 
30 
35 
40 
45 
50 
55 
60 
65 


Precision alignment and mounting apparatus

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server