U.S. patent number 3,700,011 [Application Number 05/115,747] was granted by the patent office on 1972-10-24 for terminal straightening method and machine.
This patent grant is currently assigned to Malco Manufacturing Company, Inc.. Invention is credited to George Walter.
United States Patent |
3,700,011 |
Walter |
October 24, 1972 |
**Please see images for:
( Certificate of Correction ) ** |
TERMINAL STRAIGHTENING METHOD AND MACHINE
Abstract
A method of straightening bent wire-wrap posts of electrical
terminals in a group of terminals and a machine for practicing the
method. The method contemplates bending posts misaligned with
corresponding terminal axes back into alignment with respective
axes and then twisting them on said axes through a sequence of
twists which culminates in return of the posts to generally their
original radial orientation on the respective axes and fixing of
the posts in alignment with such axes. The machine performs this
method by telescopically engaging all the terminals in a group of
terminals with a corresponding group of spindle wrenches. The
initial engagement places all wire wrap posts in alignment with
corresponding axes. Rotation of the spindle wrenches through a rack
and pinion arrangement according to a prescribed sequence is
effective to perform the aforedescribed twisting operation on the
posts in the group.
Inventors: |
Walter; George (Chicago,
IL) |
Assignee: |
Malco Manufacturing Company,
Inc. (Chicago, IL)
|
Family
ID: |
22363183 |
Appl.
No.: |
05/115,747 |
Filed: |
February 16, 1971 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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824349 |
Apr 21, 1969 |
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Current U.S.
Class: |
140/147;
140/149 |
Current CPC
Class: |
H05K
13/0076 (20130101) |
Current International
Class: |
H05K
13/00 (20060101); B21f 007/00 () |
Field of
Search: |
;140/147,149,119
;72/DIG.10 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lanham; Charles W.
Assistant Examiner: Keenan; Michael J.
Parent Case Text
BACKGROUND OF THE INVENTION
This application is a continuation of the co-pending application of
George Walter, Ser. No. 824,349, filed Apr. 21, 1969, entitled
TERMINAL STRAIGHTENING METHOD AND MACHINE, now abandoned.
Claims
I claim:
1. A method of changing the position of a bendable post and fixing
the post in a prescribed new position, comprising the steps of:
a. bending said post into said new position from a position
displaced therefrom, and
b. twisting the post generally about its axis whereby when it is
released it remains in said new position.
2. The method of claim 1 further characterized by and including the
step of:
a. holding said post in said prescribed new position while twisting
it.
3. A method of straightening the wire wrap post of an electrical
terminal seated in base means, whereby the post is moved from
misalignment with a prescribed axis of the terminal to alignment
therewith and fixed on said axis, comprising the steps of:
a. bending said post into alignment with said axis, and
b. twisting said post about said axis whereby when it is released
it remains fixed on said axis.
4. The method of claim 3 further characterized by and including the
step of:
a. twisting said post first in one direction about said axis and
then in the opposite direction about said axis.
5. The method of claim 4 further characterized by and including the
step of:
a. returning said post to generally its original radial orientation
on said axis.
6. A method of straightening the wire wrap post of an electrical
terminal seated in base means, whereby the post is returned from
misalignment with the longitudinal axis of the terminal to
alignment therewith and fixed on said axis, comprising the steps
of:
a. bending said post into alignment with said axis,
b. twisting the post in one direction on said axis through a first
predetermined number of degrees of arc from its original radial
orientation on said axis,
c. twisting the post in the opposite direction on said axis through
a second predetermined number of degrees of arc, and
d. returning said post to generally its original radial orientation
on said axis by twisting it about said axis.
7. The method of claim 6 further characterized by and including the
step of:
a. twisting the post in one direction through approximately
90.degree. of arc from its original radial orientation on said
axis.
8. The method of claim 7 further characterized by and including the
step of:
a. twisting the post in said opposite direction on said axis
through approximately 180.degree. of arc.
9. The method of claim 8 further characterized by and including the
step of:
a. returning said post to generally its original radial orientation
on said axis by twisting it in said one direction on said axis
through 70.degree. to 110.degree. of arc.
10. A method of straightening the elongated wire wrap post of an
electrical terminal extending through a bushing seated in base
means, whereby the elongated post is returned from misalignment
with the longitudinal axis of the terminal to alignment therewith
and fixed on said axis, comprising the steps of:
a. bending said post into alignment with stand axis,
b. twisting the post in one direction on said axis through a first
predetermined number of degrees of arc from its original radial
orientation relative on said axis,
c. twisting the post in the opposite direction on said axis through
a second predetermined number of degrees of arc,
d. returning said post substantially to its original radial
orientation on said axis by twisting it about said axis, and
e. distorting the metal of said post in each of said twisting steps
only in an area immediately adjacent the bushing.
11. A method of straightening randomly positioned misaligned wire
wrap posts of electrical terminals in a group of terminals seated
in base means, whereby the misaligned posts are returned from
misalignment with the longitudinal axes of corresponding terminals
to alignment therewith and fixed on said axes, comprising the steps
of:
a. gripping each wire wrap post in said group of terminals in such
a manner that said misaligned wire wrap posts are bent into
alignment with corresponding terminal axes and all the posts in
said group are in alignment with corresponding axes,
b. twisting all of said posts in one direction on corresponding
axes through a first predetermined number of degrees of arc from
their original radial orientation on said corresponding axes,
c. twisting all of said posts in the opposite direction on said
corresponding axes through a second predetermined degrees of arc,
and
d. returning all of said posts to their generally original radial
orientation on said corresponding axes by twisting them a about
said corresponding axes.
12. The method of claim 11 further characterized by and including
the step of: 11
a. twisting all of said posts in one direction through
approximately 90.degree. of arc from their original radial
orientation on corresponding axes.
13. The method of claim 12 further characterized by and including
the step of:
a. twisting all of said posts in said opposite direction on
corresponding axes through approximately 180.degree. of arc.
14. The method of claim 13 further characterized by and including
the step of:
a. returning all of said posts to generally their original radial
orientation on said corresponding axes by twisting them in said one
direction on said corresponding axes through 70.degree. to
110.degree. of arc.
Description
This invention is in the field of electrical terminal connectors.
It deals particularly with terminal connectors of the type which
include wire wrap posts on the terminals and wherein the terminals
themselves are seated in a prescribed pattern in a matrix plate or
block or the like.
It is now common practice to assemble terminal connector complexes
comprising thousands of terminal connectors seated in a matrix.
These connectors conventionally comprise a terminal pin which is
either molded into a block or mounted in a bushing which extends
through an aperture in a mounting plate. In either case, the
terminal pin conventionally has formed, on at least one of its two
ends, a wire wrap post. It is the function of this wire wrap post
to receive, by well-known wire wrapping techniques, the bared end
of a conductor wire.
In practice, a large plate, for example, containing a complex of
several thousand terminal connectors in closely spaced
relationship, is positioned in a predetermined manner on an
automatic wire wrapping machine. The plate is precisely located on
the bed of the wire wrapping machine so that a wire wrap head can
successively descend, wrap the bared end of a conductor wire around
a predetermined wire wrap post, ascend, and proceed to the next
selected post to make a wire wrap connection. Since the terminal
pins are all precisely located, within certain tolerances, on the
terminal plate, proper positioning of the plate relative to the
wire wrap head normally permits the head to accurately descend and
ascend in its wire wrapping pattern in precisely the correct
relationship with each wire wrap post selected.
If a terminal pin were out of position on the plate, however, the
wire wrap head would not be properly oriented relative to the pin
and, in descending, might not grip the pin properly and thus not
wire wrap it properly. For that matter, the terminal and even the
machine itself can be damaged if this occurs. Fortunately, the
positioning of the terminal pins on the board is very accurately
controlled and mis-positioning is, for all practical purposes,
non-existant.
It is not uncommon, however, for a properly positioned terminal pin
to have its wire wrap post bent to a lesser or greater degree,
either during the terminal insertion process, or in handling of the
terminal plate once it has been assembled and before it is shipped
to a customer for connection into a computer module, for example.
In order to assure that the wire wrap post of each terminal pin is
precisely positioned on the axis of the pin, it is presently
necessary to check the positioning and attitude of each of these
wire wrap posts individually under magnification. Where a post is
found to be outside predetermined tolerances, it is individually
bent back to alignment for acceptance of the wire wrap head in the
subsequent wire wrapping operation. This is a laborious,
time-consuming, and consequently expensive operation, as will be
readily understood.
SUMMARY OF THE INVENTION
A primary object of the present invention is to provide a vastly
improved method of straightening the wire wrap post of an
electrical terminal seated in base means, whereby the post is
returned from misalignment with the longitudinal axis of the
terminal to alignment therewith and fixed on the axis. It is
another object to provide a method of straightening the randomly
distributed, misaligned wire wrap posts in a group of wire wrap
posts without the necessity of searching out the misaligned posts.
It is still another object to provide a method of straightening
randomly distributed misaligned posts in a group of posts by
uniform treatment of all of the posts. It is yet another object to
provide a method wherein the posts tensile strength remains
substantially unimpaired.
It is a further object of the invention to provide a machine for
straightening wire wrap posts which are out of alignment with the
longitudinal axes of corresponding terminal connectors. Still a
further object is to provide a machine which engages a large group
of wire wrap posts and straightens the randomly distributed
misaligned posts in the group, whereby the necessity of searching
out individual misaligned posts for straightening is obviated.
The foregoing and other objects are realized in accord with the
invention by providing a method wherein a misaligned wire wrap post
of an electrical terminal connector is first bent into alignment
with the longitudinal axis of the terminal. The post is then
twisted in one direction on this axis through a first predetermined
number of degrees of arc from its original radial orientation on
the axis. The post is then twisted in the opposite direction on the
axis past its original radial orientation through a second
predetermined number of degrees of arc. Finally, the post is once
again twisted in said one direction on the axis through a third
predetermined number of degrees of arc sufficient to return it
slightly past its original radial orientation on said axis. The
post is then released and it remains in precise alignment with the
axis.
An important feature of the method is that all wire wrap posts in a
group, both straight and bent, are treated simultaneously in the
aforedescribed manner. Thus, the randomly distributed, misaligned
posts in a group are automatically straightened without the
necessity of searching out specific misaligned posts. Another
feature of the method is that all the posts retain, virtually
intact, their physical characteristics, particularly tensile
strength. In testing, there was found to be less than a 11/2
percent decrease in tensile strength of a twisted post.
A separate aspect of the invention is the machine which can perform
the steps of the method. The machine head engages an entire group
of terminal posts. It performs the twisting operations on the
group. The head then sequences to the "next" group of terminals and
its head engages them. The twisting and straightening operation is
quickly and easily performed on all terminals in a large plate, for
example, in a simple and expeditious manner.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, including the method and a machine constructed to
automatically perform various steps of the method, together with
the objects and advantages thereof, is illustrated more or less
diagrammatically in the drawings, in which:
FIG. 1 is an end elevational view of a portion of a terminal plate
showing a printed circuit board and connector block, with parts
removed, and the two end terminals of the connector block, one of
the terminals being bent out of alignment with the axis of the
terminal;
FIG. 2 is a view similar to FIG. 1 showing the bent terminal about
to be engaged by a pinion wrench in a first step of the method
embodying features of the invention;
FIG. 3 is a further developed illustration of the first step of the
method;
FIG. 4 is a generally graphic illustration of the wire wrap post
twisting pattern employed with the specific twists illustrated and
described;
FIG. 5 is a view similar to FIGS. 1-3 illustrating the terminal
post after it has been straightened according to the method of the
invention;
FIG. 6 is an enlarged end view of the pinion wrench illustrated in
FIG. 2;
FIG. 7 is a front elevational view of a wire wrap post
straightening machine constructed according to the invention, with
parts removed;
FIG. 8 is a top plan view of the machine illustrated in FIG. 7,
also with parts removed;
FIG. 9 is an end elevational view of the machine, also with parts
removed;
FIG. 10 is a sectional view taken along line 10--10 of FIG. 8;
FIG. 11 is an enlarged front elevational view of the machine's head
mechanism which is adapted to engage and straighten terminal wire
wrap posts according to the invention, with parts removed and
others shown in section;
FIG. 12 is an enlarged, bottom plan view of a portion of the head
mechanism illustrated in FIG. 11;
FIG. 13 is a sectional view taken along line 13--13 of FIG. 11;
FIG. 14 is an enlarged sectional view taken along line 14--14 of
FIG. 11;
FIG. 15 is a further enlarged view of one of the pinion spindles of
the head mechanism illustrated in FIG. 11;
FIG. 16 is a further enlarged view of another pinion spindle from
the head mechanism of FIG. 11; and
FIG. 17 is a sectional view taken along line 17--17 of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and particularly of FIGS. 1-5, the
method embodying features of the invention is diagrammatically
illustrated. Employing the method, the bent wire wrap post 10 of
the terminal T, as seen in FIG. 1, is returned to precise alignment
with the longitudinal axis X of the terminal T, as seen in FIG. 5.
More precisely then, FIGS. 2-4 illustrate the actual steps of the
method embodying features of the invention, FIG. 1 illustrates the
terminal T with its wire wrap post 10 bent out of alignment, and
FIG. 5 illustrates that same wire wrap post 10 after straightening
according to the invention.
Turning specifically to FIG. 1, the two end terminals T and T.sub.1
in a two row connector insulator body B are illustrated. The wire
wrap post 10 of the terminal T is bent substantially out of
alignment with the longitudinal axis X of the terminal, while the
wire wrap post 10.sub.1 of the terminal T, is in substantially
precise alignment with its terminal axis Y.
The insulator body B is seated, in a well-known manner on a
terminal plate P. Bushing sleeves S and S.sub.1 of the body B
extend through corresponding apertures (not shown) in the plate P
and the terminals T and T.sub.1, in turn, extend from within the
body B through the bushing sleeves. Female portions (not shown) are
conventionally formed on corresponding ends of the terminals T and
T.sub.1 within the body B, while the opposite ends of the terminals
are formed into the wire wrap posts 10 and 10.sub.1.
In the present illustration, the terminals T and T.sub.1 and,
accordingly, the wire wrap posts 10 and 10.sub.1, are fabricated
from half-hard brass by conventional die punching methods. The
terminals are formed so that the wire wrap posts 10 and 10.sub.1
are approximately 0.025 inch square in cross-section.
Pyramid-shaped tips 11 and 11.sub.1 are formed, in a well-known
manner on the free ends of corresponding posts 10 and 10.sub.1, to
facilitate ultimate machine wire wrapping.
Referring now specifically to FIGS. 2 and 3, the first step of the
method for straightening the wire post 10 of the terminal T,
according to the present invention, is bending the post 10 into
alignment with the axis X of the terminal. In practice, this is
accomplished by a spindle wrench 15 which is mechanically aligned
with the axis X.
The spindle wrench 15 has an elongated bore 16 which is square in
cross-sectional configuration. Referring to FIG. 6, the
cross-sectional dimensions of the bore 16 are slightly greater than
the cross-sectional dimensions of the post 10. A downwardly
widening frusto-conical mouth 17 is formed in the lower end of the
spindle wrench 15, providing access to the relatively smaller bore
16.
The spindle wrench is brought downwardly onto the post 10 in
alignment with the axis X. The cross-sectional dimensions of the
mouth 17 are such that as the spindle wrench 15 moves downwardly, a
wire wrap post 10 which is bent even considerably out of line with
the axis X will enter the mouth 17. The pyramid shaped tip 11 on
the post 10 is an aid to this, of course.
As the spindle wrench 15 continues to descend, the mouth 17 directs
the free-end of the wire wrap post 10 toward the bore 16 of the
wrench, thus bending the post toward the axis X. FIG. 3 illustrates
the arrangement of the wire wrap post 10 within the bore 16 of the
spindle wrench 15 when the spindle wrench has reached its lowermost
position. In this position, the greater portion of the post 10 is
telescoped in the bore 16, while a short section 20 of the post
immediately adjacent the corresponding bushing sleeve S remains
outside of the bore 16. The entire post 10 is aligned with the axis
X.
With the post 10 telescoped within the bore 16 of the spindle
wrench 15 in the aforedescribed manner, the next step is to twist
the post 10 on the axis X, according to the invention. Referring to
FIG. 4, the spindle wrench 15 is first rotated about its axis in
one direction (counter-clockwise) for a predetermined number of
degrees. Because the post 10 is square in cross-sectional
configuration and telescoped within the square bore 16 of the
spindle wrench 15, it is twisted on the axis X through a
corresponding number of degrees. For reasons hereinafter discussed
in greater detail, with the terminal T illustrated and the relative
length of the post section 20, this predetermined first number of
degrees of rotation is through an arc of approximately 90.degree..
The full twisting of the post 10 takes place in the section 20 at
the base of the terminal post 10.
After the spindle wrench 15 has twisted the post 10 through a first
angular distance of 90.degree. in said one direction, rotation of
the wrench 15 is stopped in that direction and it is rotated in the
opposite direction (clockwise) through approximately 180.degree..
Accordingly, the wire wrap post 10 is twisted in the opposite
direction on the axis X through approximately 180.degree., the
twisting all taking place in the section 20 at the base of the post
10.
Having rotated in the opposite direction through a predetermined
number of degrees, 180.degree. in the present illustration,
rotation of the spindle wrench 15 in that direction is halted. The
wrench 15 is then rotated in the original (counter-clockwise)
direction on the axis X through approximately 110.degree. of arc.
When the post 10 has been twisted through this approximately
110.degree. arc on the axis X, the spindle wrench 15 is raised to
release the post. As seen in FIG. 5, the post 10 remains in
substantially perfect alignment with the axis X of the terminal
once it has been treated with the aforedescribed twisting
operations. It does not return to its original, misaligned position
because metal in the section 20 at the base of terminal post 10 has
been deformed, i.e., twisted, beyond its limit of elastic
deformation.
The sequence and degree of twisting described is particularly
suited to terminals of the type illustrated; i.e., half-hard brass
terminals having 0.025 inch square wire wrap posts wherein the
terminals are fabricated from sheet stock by die punching or the
like. These factors, as well as others, determine exactly how the
post 10 is twisted.
If the type of material, that is the composition of the metal alloy
in the terminal T is varied, it should be understood that the
sequence and degree of twisting would be modified. Similarly,
depending upon how the terminal pin is fabricated, i.e., by
punching, drawing, etc., this treatment would further vary. The
effect of plating the metal terminals, heat-treating them, or
treating the surface in some other way has similar effects on the
manner in which the terminal is twisted according to the
invention.
The twisting operation is also modified within the perview of the
invention when wire wrap posts of different shape are employed.
Furthermore, by varying the length of the section 20 which is
actually stressed during the twisting operation of the post 10, the
type and extent of twisting can be modified.
In essence, there are three major variables in the twisting
operation. These major variables can, in turn, be broken down. In
summary, they are as follows:
1. The material characteristics of the wire wrap post,
including
a. type of material (various metal alloys)
b. inherent stress lines in material (determined by metal grain
structure as, in turn, effected by the method of forming the metal,
i.e., punching, drawing, etc.)
c. treatment of the material (heat-treated, pickled, plated,
etc.)
2. The physical shape and dimensions of the wire wrap post.
3. The length of the section of the wire wrap post which is being
stressed during the twisting operation.
The variables each affect the twisting scheme for a prescribed
terminal. Regardless, however, the wire wrap post in question is
bent into proper alignment, twisted from its original radial
orientation on the axis and finally twisted again to substantially
its original orientation. In practice, the final radial orientation
may be slightly different than the original, but this is of no
consequence or purpose.
Turning now to FIGS. 7-17, a machine developed to perform the
method of the invention is illustrated. Referring specifically to
FIGS. 7, 8, and 9, the machine is illustrated generally at 30. The
machine 30 is effective to engage a large group or row of
terminals, as seen in FIG. 7, simultaneously twist each terminal in
the row, according to the invention, and sequentially move to
succeeding rows of terminals to perform the same operation.
Still referring to FIGS. 7-9, the machine includes a generally
rectangular plate 35, upon which is mounted, in a conventional
manner, a slightly smaller rectangular base plate 36. In turn, a
somewhat smaller, rectangular mounting plate 37 is secured in a
conventional manner to the upper surface of the base plate 36.
Supported for movement from front to back on the mounting plate 37
is a platen assembly 40. The platen assembly 40 includes a
longitudinally extending side bar 41 joined by transversely
extending front and back stringers 42. Extending transversely
between the side bars 41, intermediate the front and back stringers
42, is an elongated, rectangular work platen 45. It is on the work
platen 45 that the matrix plates P, for example, containing groups
or rows of terminals T, are mounted for straightening by the
machine 10, all in a manner hereinafter discussed in detail.
The platen assembly 40 is mounted for sliding movement, front to
back, on the mounting plate 37, on horizontal mounting shafts 50
secured to the mounting plate. The shafts 50 are transversely
spaced, as illustrated best in FIGS. 7 and 8, and are rigidly
supported from the mounting plate 47 by machine bolts 51 extending
up through the plate and spacer saddles 52 between the plate and
the corresponding shaft, as best seen in FIG. 10. At least two
mounting collars 53 (only one shown) are secured to each side bar
of the platen assembly 40 in front-to-back spaced relationship, and
these collars encircle and mount the platen assembly 40 on the
mounting shafts 50. As seen in FIG. 10, the collars are box-like in
external configuration and have a split, bearing sleeve liner 54
extending transversely therethrough for engaging and sliding on the
corresponding shaft 50 in bearing relationship. The bearing rings
54 are split, as illustrated, to afford access to the mounting
bolts 51 and spacer saddles 52 supporting the shafts 50.
Suitably mounted in the four corners of the base plate 36, and
extending upwardly therefrom, are four identical guide posts 60.
Vertically slideable on the guide posts 60 is a head assembly 61.
The head assembly 61 includes, according to the present invention,
head mechanism 62 which engages the wire wrap post 10 of terminals
T on the matrix plate P, and straightens bent wire wrap posts
according to the method of the invention.
The head assembly 61 comprises a generally rectangular head plate
65 which mounts four bearing sleeves 66 through which the posts 60
extend. In operation, the plate 65 moves vertically on the post 60
to bring the head mechanism 62 into and out of engagement with the
terminals T as each row or group of terminals is processed, all in
a manner hereinafter discussed.
The head mechanism 65 is illustrated in substantial detail in FIGS.
11-16. Referring to these fingers, the head mechanism 62 is seen to
include an elongated housing 70, rectangular in cross-section (see
FIG. 13), and secured to the bottom of the head plate 65. The
housing 70 includes a roof plate 71 actually secured to the head
plate by conventional means such as machine bolts or the like (not
shown). A floor plate 72 is secured to the roof plate 71, also by
conventional means such as machine bolts (not shown), and the
opposed surfaces of the roof plate 71 and floor plate 72 are so
shaped as to define a stepped slot 75 extending the length of the
housing 70 adjacent the front of the housing. A face plate 76 forms
a front closure for the stepped slot 75 and defines the front face
of the housing 70. The face plate 76 is secured to the roof plate
71 by two conventional side bolts 80 and, to facilitate easy
handling of the face plate 76 when the side bolts 80 have been
removed preparatory to removing the face plate, a center bolt 81
with a knurled head for hand turning.
The face plate 76 serves as a carrier for a series of closely
spaced spindle wrenches 15. Each of these spindle wrenches 15 is
identical in construction, and has hereinbefore been described in
detail in relation to the method embodying features of the
invention.
Each pinion wrench 15 is mounted on a pinion gear spindle 85.
However, alternate spindle wrenches 15 are mounted on alternating
forms 85a and 85b of the pinion spindles. These alternating forms
of pinion spindles 85a and 85b are shown in substantial detail in
FIGS. 15 and 16. Each includes a rectangular cross-section tip 87a
and 87b upon which the spindle wrench 15 is forced in press-fit
relationship, a suitable end aperture being provided in the end of
each wrench 15 to receive the corresponding tip. In the pinion
spindle 85a, however, the pinion gear 88a is displaced upwardly
relative to the pinion gear 88b on the pinion spindle 85b. As a
result, the pinion spindles 85a and 85b with their attached pinion
wrench 15 nest in closely spaced relationship on an inner ledge 90
extending the length of the face plate 76.
Suitably formed bores 91a and 91b extend downwardly through the
face plate 76 from the ledge 90 and are adapted to receive the
distinctly shaped lower bearing stubs 92a and 92b of the pinion
spindles 85a and 85b, respectively, as well as the pinion wrenches
15 themselves. The pinion spindles 85 with their attached pinion
wrenches 15 are thus mounted for rotation in the bores 91a and 91b
on the axes of corresponding bores.
With the face plate 76 seated in place, as illustrated in FIG. 13,
upper stub bearings 93a and 93b on the pinion spindles 85a and 85b,
respectively, seat in corresponding stub bores 95 formed in the
lower face of the roof plate 71 in spaced relationship along its
front edge. The snugly nested pinion gears 88a and 88b are spaced
along the length of the gear cavity 97 formed within the housing
70.
The pinion gears 88a and 88b are rotated by an elongated rack 100
slideably mounted in the outer portion of the stepped slot 75
through the housing 70. The rack 100 is in mesh with both pinion
gears 88a and 88b and is rigidly secured on an elongated carrier
bar 101 extending through the larger inner portion of the slot 75.
Movement of the carrier bar 101 in the slot 75 is effective to
rotate the pinion gears 88a and 88b in either a clockwise or
counter-clockwise direction, depending upon the direction of
movement of the carrier bar 101, and thus rotate the spindle
wrenches 15 accordingly.
The carrier bar 101, and accordingly, the rack 100 is moved
longitudinally through the slot 75 to rotate the spindle wrenches
15 by the power train assembly 105 of the head mechanism 62. The
power train assembly 105 includes a conventional electric motor 106
secured to a mounting bracket 107 on top of the head plate 65. The
motor 106 is a horsepower motor of any well-known commercial
type.
The motor 106 is connected through a drive shaft and coupling 109
to a speed reducer sub-assembly 110, also of conventional
construction, which contains suitable gearing for reducing output
shaft speed. The speed reducer sub-assembly 110 has a vertically
depending output shaft 111 extending through a suitably formed
aperture in the head plate 65. The speed reducer 110 is mounted in
a suitable manner on the top of the head plate 65.
Referring particularly to FIGS. 7, 11 and 12, the lower end of the
speed reducer output shaft 111 extends below the head plate 65 and
mounts an annular disc 115 in rigidly connected relationship. A
drive link 116 is pivotally connected, in eccentric relationship at
117, to the disc 115 and, in turn, is pivotally connected to a
corresponding end of the carrier bar 101 at 118.
It should now be seen that rotation of the disc 115 causes the bar
101 to reciprocate in the stepped slot 75, and the bar carries the
rack 100. It will further be recognized that the extent of
longitudinal movement of the rack 100 is determined solely by the
degree of eccentricity of the pivotal connection 117. It is, of
course, the extent to which the rack 100 moves longitudinally in
the slot 75 that determines the degree of rotation, in either
direction, of the spindle pins 85 and, accordingly, the spindle
wrenches 15.
Referring to the method of the invention hereinbefore described,
the desired amount of twisting of various wire wrap posts
fabricated of varying materials, of varying size and configuration,
having been treated in various ways, varys considerably. For
purposes of illustration, however, in accord with optimum practice
where a terminal T of the type described is used, a 90.degree.
counter-clockwise twist, followed by a 180.degree. clockwise twist,
followed in turn by approximately a 110.degree. counter-clockwise
twist, produces precise alignment of bent terminal wire wrap posts
10 of the terminals T with the axes X of these terminals while
having minimal effect on the desirable physical characteristics and
properties of the metal terminal.
The rack travel and gear ratio relationship of the rack 100 and the
pinion gears 88a and 88b are coordinated with the degree of
eccentricity of the pivot 117 from the center of rotation of the
disc 115 to provide that in one complete rotation of the disc 115
each spindle wrench 15 will rotate through 360.degree., 180.degree.
in a counter-clockwise direction followed by, or preceeded by,
180.degree. of rotation in a clockwise direction. With this in
mind, to obtain the required sequence and degree of rotation of the
spindle wrenches 15 in the present illustration, the motor is
controlled in a manner hereinafter discussed so that when the
spindle wrenches 15 descend and engage a row of terminals T, the
radial of the disc 115 passing through the centerpoint of the
pivotal connection 117 for the drive link 116 is at 0.degree., as
seen in FIG. 12.
When the motor 106 is energized, the disc 115 is rotated in a
counter-clockwise direction. As the aforementioned radial passes
through the 270.degree. position on the compass (rotating in a
counter-clockwise direction) each spindle wrench 15 has rotated in
a counter-clockwise direction for 90.degree., thus twisting
corresponding wire wrap posts 10 correspondingly. Continued
counter-clockwise rotation of the disc 115 until the aforementioned
radial reaches the 90.degree. position on the compass, as seen in
FIG. 12, causes the spindle wrenches 15 to reverse their direction
of rotation (at the 270.degree. position) and rotate through
180.degree. in the opposite, or clockwise direction. The wire wrap
posts 10 are twisted accordingly.
Continued rotation of the disc 115, wherein the radial of the disc
passing through the center of the pivotal connection 117 moves in a
counter-clockwise direction from the 90.degree. position to, and
past, the 0.degree. position to the 340.degree. position, again
effects reversal of the rotation of the spindle wrenches 15. The
spindle wrenches 15 during this segment of rotation of the disc 115
are rotated once again in a counter-clockwise direction, through
approximately 110.degree.. The wire wrap post 10 telescoped within
the wrenches 15 are twisted accordingly. At this point, the
wrenches 15 are withdrawn from engagement with the row of terminal
posts 10, all of the terminal posts 10 in this group of terminals
again being in perfect alignment with the corresponding axes of the
terminals and, accordingly, ready for automatic wire wrapping.
Automatic control of the motor 106 for precisely the desired
380.degree. of counter-clockwise rotation is afforded by suitable
circuitry, a starting switch (not shown), and a cooperating limit
switch assembly 125, seen in FIG. 14. The limit switch assembly 125
includes a conventional three-way switch 126 whose switching
functions are controlled by a cam arm 127 carrying a roller 128.
The cam roller 128 is spring-loaded into engagement with one or the
other of the cam surfaces 135 and 136 formed on the free end of the
carrier bar 101 which mounts the rack 100.
In operation of the head mechanism 62 by the power train assembly
105, assume that the radial of the disc 115 extending through the
pivotal center of the pivot point 117 is at 0.degree., as
illustrated in FIG. 12. Actuation of the motor circuit by the
starting switch (not shown) draws the carrier bar 101 to the left
in FIG. 14, causing the cam surface 135 to depress the arm 127 and
actuate the switch 126, thus setting up a holding circuit through
the switch 126 to maintain the motor 106 in operation.
When the disc has rotated through 360.degree. from 0.degree.,
counter-clockwise back to 0.degree., the cam surface 136 engages
the cam roller 128 and begins to depress the cam arm 127. The cam
arm 127 is not completely depressed until the carrier bar 101 has
travelled sufficiently to move the adjoining cams 135, 136 over
dead-center of the roller 128 and bring the cam surface 136 into
engagement with the roller. At this point, the holding circuit to
the motor 106 is broken and an additional 20.degree. of
counter-clockwise rotation of the disc 115 has taken place. The
motor 106 stops and the straightening of one row or group of
terminal posts 10 is completed. When the head mechanism is
withdrawn from engagement with the post 10, a spring centering
arrangement (not shown) in the speed reducer 110 once again centers
the disc 115 with the aforementioned radial at 40.degree.,
preparing it for the next twisting cycle.
The machine 30 has been described in terms of its engagement with a
single group, or row, of terminals to twist all the terminals in
that row according to the method of the invention, and, as a
result, straighten those wire wrap posts 10 in the row which might
be bent out of alignment with corresponding axes of the terminals.
The machine 30 has the capacity, however, to successively engage
and treat an extended series of these rows of terminals. As such,
it moves from row to row in a manner hereinafter discussed.
As seen in FIGS. 7 and 9, a lift mechanism 130 is provided for
raising the head assembly 61 to disengage the spindle wrenches 15
from the terminals T and T.sub.1 when a selected row of terminals
has been treated according to the invention. The lift mechanism 130
is actuated by the machine 30 operator to raise the head assembly
61, after which the platen assembly 40 is indexed rearwardly a
distance equal to the distance between the rows of terminals on the
terminal plate P and the next row of terminals is caused to be
engaged by the spindle wrenches 15 as the head assembly 61 is
lowered.
Indexing is accomplished by the operator through an indexing
mechanism 135 illustrated at FIGS 8 and 17. The lift mechanism 130
is provided with a stop-safe mechanism 140, as seen in FIG. 10,
which prevents the head assembly 61 from descending to cause the
spindle wrenches 15 to engage terminals in the next row of
terminals unless the indexing operation has precisely located the
next row of terminals for receipt of the spindles.
The lift mechanism 130 includes a torque shaft 145 extending
between and journalled in identical pillow blocks 146 secured to
the underside of the bed plate 35 of the machine 30. Each end of
the torque shaft 145 (only one shown) outside of the corresponding
pillow block 146, mounts a crank arm 148 in transversely extending
relationship. The inner end of each of these crank arms 148, as
seen in FIG. 9, is pivotally connected to a vertically extending
lift rod 149 which passes through suitably formed apertures in the
plates 35 and 36 and is secured to the underside of the head plate
65 through a thread nut and bolt assembly 150.
The opposite end of each lever arm 145 is pivotally connected to a
power link 152 extending downwardly therefrom. The power link 152
is connected to a suitable motor and control arrangement (not
shown) which draws it down and raises it a predetermined distance
at the instance of the operator.
In the present illustration, when the operator actuates the control
mechanism to draw the power link 152 downwardly, the rod 149 lifts
the head assembly 61 upwardly a distance of approximately 3/4 inch
to 1 inch. The specific maximum rise of the head assembly 61 is not
important. It is only necessary that the head assembly rides
sufficiently to clear the spindle wrenches 15 of the top of the
terminals for indexing to the next row of terminals, a distance
obviously determined solely by the height of the wire wrap posts 10
of the terminals.
When a predetermined row of terminals has been engaged, twisted,
and disengaged in the aforedescribed manner, the operator toggles
the indexing mechanism 135 to index the terminal plate P rearwardly
for precisely the distance between the rows of terminals. To this
end, the indexing mechanism 135 includes a pair of indexing, guide
plates 155a and 155b mounted on opposite sides of the platen
assembly 40 on the mounting collars 53. The guide plates 155a and
155b are best seen in FIGS. 7, 10 and 17. The plates 155a and 155b
are secured to the corresponding mounting collars 53 in a
conventional manner by machine bolts 156 and extend outwardly of
the collars into guide slots of the stop-safe mechanisms 140 on
opposite sides of the platen assembly 40.
The guide plate 155a has a longitudinally spaced series of index
apertures 160 formed in it, as illustrated in FIG. 17. Movable in
and out of engagement with the apertures 160 is the actuator finger
161 of the indexing mechanism 135.
Pivotally mounted on adjacent structure 163 fixed to the mounting
plate 37 of the machine 30 is a toggle arm 166; the pivotal
connection 167 being best seen in FIG. 17. A depending leg 169 of
the arm 166 is, in turn, pivotally connected in lost-motion
relationship at 170 with the actuator finger 161, intermediate its
ends. An actuator tooth 175 on the actuator finger 161 actually
depends into the apertures 160 and is biased into each aperture by
a spring loaded pin 176 and cooperating coil spring 177 mounted in
the structure 163 immediately above the corresponding end of the
actuator finger 161.
In operation, to index the platen assembly 40 rearwardly and thus
bring a next row of terminals into position under the sprindle
wrenches 15, the operator lifts the horizontal leg 180 of the
actuator finger 161, causing it to pivot around its connection 167
and draw the actuator finger 161 to the right, as seen in FIG. 17.
The inclined surface 181 on the tooth 175 rides up out of the
aperture 160 in question, and the finger 161 is retracted until the
tooth 175 is in position to descend into the next aperture 160 in
line. The spring loaded pin 176 thrusts the tooth 175 downwardly
into this aperture 160, and the operator presses downwardly on the
finger arm 180. This causes the finger arm 180 to thrust the
actuator finger 161 to the left, as seen in FIG. 17, driving the
plate 155a and, accordingly, the platen assembly 40 rearwardly for
the prescribed distance.
The platen assembly 40 should then be in precise position relative
to the head assembly 61 so that the spindle wrenches 15 can descend
and precisely engage the next row of terminals on the terminal
plate. The operator manipulates the mechanism 130 to bring the head
assembly downwardly. Should the next row of terminals not have been
brought into precise alignment for receipt of the spindle wrenches
15, however, the stop-safe mechanism 140 is effective to prevent
this power movement of the head assembly 61.
Referring specifically to FIG. 10, the stop-safe mechanism 140
(there is one on each side of the platen a assembly 40 but only one
is shown) includes a row of precisely positioned apertures 190
(only one shown) in the index guide plates 155a and 155b, extending
parallel to the longitudinal edge of the plates and, in the case of
the plate 155a, parallel to the apertures 160. The apertures 190
are precision machined in the plates 155a and 155b so that one of
the apertures is in exact alignment with each row of terminals T,
T.sub.1 when the terminal plate P is mounted on the platen assembly
40.
The stop-safe mechanism 140 includes a mechanism tower 191 which
slidably mounts a locator pin 192 having a frusto-conical tip 193
formed on it. The pin 192 is connected, through a lost-motion
linkage assembly 195, with a cut-off switch assembly 196. As the
head assembly 61 descends, if the platen assembly 40 is in
precisely the right position, as indexed by the indexing mechanism
135, the pin 192 enters the appropriate aperture 190 and passes
through it into a pin receiving sleeve 196. Extending up into the
sleeve 196 is a spring biased pin 197 which accomodates any slight
overtravel of the pin 192.
If the platen assembly is not in precise alignment for receipt of a
prescribed row of terminals T and T.sub.1 by the spindle wrenches
15 as the head assembly 61 descends, the pin 192 does not enter a
corresponding aperture 190 but is, instead, forced upwardly by
engagement with the surface of the corresponding guide plate 155a
or 155b. Upward movement of the pin 192 causes the lost-motion
assembly 195 to actuate the stop-switch assembly 196 and cut off
power to the power train assembly 195, thus stopping the descent of
the head assembly 61. It is thus assured that the machine 30 will
operate to straighten each row of terminals in the plate P after
engagement with them only when precise alignment for receipt of the
terminals is established by the index mechanism 135 each time the
platen assembly 40 is indexed.
* * * * *