U.S. patent number 3,898,724 [Application Number 05/522,329] was granted by the patent office on 1975-08-12 for impact tool.
This patent grant is currently assigned to Bell Telephone Laboratories, Incorporated. Invention is credited to Theodore Alan Conorich.
United States Patent |
3,898,724 |
Conorich |
August 12, 1975 |
Impact tool
Abstract
An impact tool for such applications as terminating wire in
bifurcated terminals comprises an impact mechanism having a hammer
substantially enclosed within a power spring. The return spring is
located in a passage within the hammer and the impact surface of
the hammer is about the internal passage. Thus a large mass hammer
and springs which provide substantial impact forces and energy can
be utilized without requiring an excessive overall size of length
for the mechanism. A variety of heads can be powered by the
mechanism for seating and trimming a plurality of conductors
simultaneously and for seating multipair connector blocks.
Inventors: |
Conorich; Theodore Alan (East
Orange, NJ) |
Assignee: |
Bell Telephone Laboratories,
Incorporated (Murray Hill, NJ)
|
Family
ID: |
24080433 |
Appl.
No.: |
05/522,329 |
Filed: |
November 11, 1974 |
Current U.S.
Class: |
29/566.4; D8/51;
7/107; 29/749; 173/120; D8/75; 29/254; 30/277 |
Current CPC
Class: |
H01R
43/015 (20130101); Y10T 29/53839 (20150115); Y10T
29/53217 (20150115); Y10T 29/5151 (20150115) |
Current International
Class: |
H01R
43/01 (20060101); H01R 043/00 () |
Field of
Search: |
;29/23HC,23HT:23H,23HM,23MW ;7/14.1R ;30/277 ;173/119,120 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hall; Carl E.
Attorney, Agent or Firm: Hooper; A. D.
Claims
What is claimed is:
1. A tool adapted for terminating wires in bifurcated terminals
comprising a head for contacting said wires, a plunger on which
said head is mounted for moving said head with respect to said
terminals, and an impact mechanism for impacting said plunger to
thereby apply forces to said head to terminate said wires
characterized in that said impact mechanism includes:
a hammer having an internal passageway therethrough to receive said
plunger therein, said plunger includes a flange thereabout and said
passageway includes a shoulder around the periphery thereof adapted
to impact said flange;
a power spring surrounding substantially the entire length of said
hammer for imparting a force to said hammer for impacting said
plunger; and
a return spring about said plunger within said passageway for
returning said plunger to an initial position after said
impacting.
2. Apparatus in accordance with claim 1 wherein said flange and
said shoulder have conically tapered mating surfaces whereby the
tendency of said flange to deflect when said hammer impacts said
plunger is reduced.
3. Apparatus in accordance with claim 1 wherein said head
includes:
a holder mounted on said plunger;
an insert detachably mounted in said holder and including a body
adapted for insertion over said bifurcated terminals, and fingers
extending from said body to contact said wires in said terminals,
said fingers being responsive to said impacting of said plunger for
seating said wires in said terminals.
4. Apparatus in accordance with claim 3 wherein said body includes
first and second substantially parallel sides separated by a groove
into which said terminals fit when said body is inserted over said
terminals, said fingers comprise opposing pairs of said fingers
extending from said sides into said groove whereby a respective
said wire is contacted on both sides of said terminal.
5. Apparatus in accordance with claim 4 further including cutting
means associated with each of said fingers along one of said sides,
said cutting means being adapted for severing said wires whereby
said wires can be seated in said terminals and trimmed along one of
said sides of said terminals in response to said hammer impacting
said plunger.
6. Apparatus in accordance with claim 5 wherein said body includes
ten each of said fingers and said cutting means whereby five pairs
of said wires can be seated and trimmed simultaneously.
7. Apparatus in accordance with claim 3 wherein said insert
includes ten of said fingers whereby five pairs of said wires can
be seated simultaneously.
8. Apparatus in accordance with claim 3 wherein said head further
includes an energy absorbing pad mounted between said insert and
said holder for absorbing excessive energy imparted to said plunger
by said impacting.
9. Apparatus in accordance with claim 8 wherein said pad comprises
neoprene rubber.
10. Apparatus in accordance with claim 1 including a housing having
first and second end caps in in which said impact mechanism is
mounted with said plunger extending from an opening in said second
end cap;
said hammer comprising a substantially cylindrical hammer having a
first flange around a first end thereof adjacent said second end
cap;
said power spring extends between said first flange and said first
end cap with said hammer substantially surrounded thereby;
trigger means in said hammer extending into said passageway for
blocking movement of said plunger through said hammer when a force
is applied to said handle to thereby compress said power spring and
for releasing said plunger when said power spring is substantially
compressed whereby said power spring moves said hammer to impact
said plunger; and
said passageway includes a second shoulder therein; said return
spring being mounted about said plunger between said second
shoulder and said flange so that said return spring is compressed
when said plunger is released by said trigger means.
11. A tool adapted for uses such as terminating wires in bifurcated
terminals comprising an impact mechanism having a plunger for
transmitting forces, a hammer for impacting said plunger to impart
forces thereto, a power spring for driving said hammer against said
plunger when said power spring is released from a compressed state,
trigger means for controlling the compression of said power spring
from an initial state to said compressed state and releasing said
power spring from said compressed state, and a return spring for
returning said tool to said initial state, characterized in
that:
said power spring surrounds substantially the entire length of said
hammer;
said hammer includes an internal passage therethrough in which a
portion of said plunger is received; and
said return spring surrounds said portion of said plunger within
said passage.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a tool for seating and trimming wires and
mounting connector blocks on bifurcated electrical terminals.
2. Description of the Prior Art
Connectors having bifurcated or split terminals into which
conductors are inserted for termination are widely used in the
telephone systems. One such connector which is finding increasing
usage is known as an "88-type" connector and is described in U.S.
Pat. Nos. 3,611,264 and 3,631,378 issued to B. C. Ellis, Jr. on
Oct. 5, 1971 and Dec. 28, 1971, respectively, and assigned to
applicant's assignee. This 88-type connector includes an index
strip in which wires are seated and then trimmed. Multipair
connector blocks such as five-pair blocks are then mounted over the
index strip to establish connection with the wires therein. The
blocks then provide terminals on their opposite edge to which
cross-connect wires can be terminated.
In order to reduce installation time it is required that multiple
wire pairs, e.g., five pairs, simultaneously be seated in the index
strip and trimmed if desired. However, the forces and energy
required for such simultaneous operations on multiple wire pairs
and the forces and energy required for mounting connector blocks on
the index strip are higher than those which can be reasonably
applied by a craftsperson over an extended period with the brute
force manual tools presently available. While presently known
impact termination tools such as shown in U.S. Pat. No. 3,708,852
issued to J. R. Mason on Jan. 9, 1973 do eliminate the brute force
requirement of prior tools, they are designed for single terminal
operation and accordingly do not provide anywhere near the energy
and force levels required for the simultaneous seating and trimming
operations on the connector block mounting operation previously
discussed. A mere scaling up of these known impact termination
tools to provide the high energy and force levels required would
result in a tool much too long and large to be practical. Further,
these prior tools are designed for a different type connector,
i.e., a "66-type" connector, and are thus not directly compatible
with the newer 88-type connector.
Accordingly it is an object of this invention to improve impact
termination tools to provide higher energy and force levels.
Another object is to provide an impact termination tool which can
perform operations on a multiplicity of conductor pairs
simultaneously.
Still another object is to provide a tool which can seat and trim a
plurality of wires and mount connector blocks on bifurcated
terminals.
SUMMARY OF THE INVENTION
The foregoing objects and others are achieved in accordance with
this invention by a termination tool comprising a handle having a
plunger extending therefrom to which a head is fastened for seating
and trimming a plurality of wires in bifurcated terminals or for
mounting connector blocks. An impact mechanism within the handle
impacts the plunger to provide the required high force and energy
levels for the seating, trimming and mounting operations. The
impact mechanism comprises a high mass hammer having an axial
passageway therethrough for receiving the plunger. A conical
tapered impact shoulder around this passageway is adapted for
impacting with a conical flange on the plunger. A power spring
surrounds substantially the entire length of the hammer to provide
a high acceleration force thereto upon triggering to thereby cause
the hammer to impact the plunger with high forces. A return spring
surrounds the plunger within the passageway to return the mechanism
to its initial configuration after the impact.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be more fully comprehended from the following
detailed description and accompanying drawing in which:
FIG. 1 is a longitudinal sectional view of the termination tool of
this invention;
FIG. 2 is a perspective view of a portion of one type of head for
use with the tool of FIG. 1 for simultaneously seating a plurality
of wire pairs, and for mounting connector blocks; and
FIG. 3 is a perspective view of a portion of a second type of head
for simultaneously seating and trimming a plurality of wire
pairs.
DETAILED DESCRIPTION
As shown in FIG. 1, the tool 101 of this invention comprises a
hollow cylindrical housing 2 having threaded ends 4 and 6 into
which threaded end caps or covers 8 and 10, respectively, can be
screwed. Cap 8 has a pin 12 extending therefrom for reasons to be
discussed subsequently. Cap 10 has an axial opening 14 therethrough
for slidably receiving a plunger or rod 16 therein so that one end
18 of the plunger 16 extends from housing 2 while the other end 19
extends upward in housing 2. The end 18 of plunger 16 can be
threaded or otherwise adapted to have mounted thereon a head 20
which contacts the wires and connector blocks to perform the
seating, trimming and mounting operations thereon as will be
discussed subsequently.
Plunger 16 includes a flange or shoulder 22 thereabout which limits
the outward movement of plunger 16 by contacting cap 10. One side
24 of flange 22 provides an impact surface or anvil for imparting
an impact force to plunger 16. This side 24 is conically tapered so
that flange 22 can only deform in compression from an impact force
on surface 24 thereby eliminating the cantilevered anvil effect
which would otherwise result from an impact force on an edge or
side of the flange 22.
Plunger 16 includes a slot or keyed groove 26 along a portion of
its length. A key or pin 28 extends through cap 10 substantially
transverse to plunger 16 into slot 26, thereby preventing rotation
of plunger 16 in cap 10 while allowing free axial sliding
movement.
A heavy mass hammer 30 is located within housing 2. Hammer 30 has
an internal axial opening or passage 32 therethrough including
lower, middle and upper portions 34, 36, and 38, respectively,
having different diameters and into which end 19 of plunger 16
extends. The junction between lower section 34 and middle section
36 comprises a shoulder 40 about the periphery of passage 32.
Shoulder 40 has a conical tapered configuration to match that of
side 24 of flange 22. Shoulder 40 is the portion of hammer 30 which
impacts plunger 16.
A coil return spring 42 surrounds the part of plunger end 19 within
portions 34 and 36 of passage 32. Spring 42 abuts a shoulder 44 at
the junction of portions 36 and 38 and also abuts surface 24 of
flange 22. When plunger 16 is pushed upward through passage 32,
return spring 42 is compressed and thereby tends to return plunger
16 to its initial position with flange 22 contacting cap 10.
Hammer 30 includes a lip or flange 46 about its lower edge. A
relatively large or heavy coil spring 50, substantially stronger
than return spring 42, abuts flange 46 and extends upward about the
entire remaining length of hammer 30. Spring 50 abuts cap 8 at the
top of housing 2 so that spring 50 is compressed between cap 8 and
flange 46 when hammer 30 is pushed upward with respect to housing
2.
A circumferential groove 52 is formed about the upper exterior of
hammer 30 and includes a slot or wedge portion 54 extending through
the wall of hammer 30 into passage portion 38. A trigger or sear 56
is slidably mounted in slot 54. Sear 56 includes a cam or wedge
surface 58 about the upper portion of its inner edge. A spring clip
60 is mounted in groove and about sear 56 to resiliently urge sear
56 to extend into passage 38. In this position sear 56 contacts the
upper end 19 of plunger 16 to prevent plunger 16 from moving any
substantial distance upward with respect to hammer 30.
When a manual force is applied to handle 2 in a direction to cause
seating and trimming of wires or mounting of connector blocks
engaged by head 20, i.e., in the direction of arrow 59, end 19 of
plunger 16 contacts trigger 56 to prevent further movement of
plunger 16 upward through passage 32. Further application of force
pushes hammer 30 and plunger 16 upward in housing 2 to compress
spring 50. When the top end of hammer 30 reaches cap 8, spring 50
is nearly fully compressed. At this point, pin 12 on cap 8 engages
the cam surface 58 of trigger 56 thereby camming or pushing trigger
56 aside out of passage 38. When trigger 56 is pushed aside a
sufficient distance, the end 19 of plunger 16 can get by trigger 56
allowing the compressed spring 50 to drive hammer 30 downward with
respect to plunger 16 so that shoulder 40 impacts surface 24. This
impact is transmitted to head 20 for the seating, trimming, et
cetera operations. Upon removal of the force from handle 2, return
spring 42 returns plunger 16 to its initial position for the next
stroke.
The described impact mechanism has significant advantages over
those in the prior art. The placement of substantially the entire
length of hammer 30 within power spring 50 allows a much larger
hammer and a longer spring to be used thereby providing
substantially greater impact forces. The placement of the return
spring 42 and impact surfaces 24 and 40 internal to hammer 30 is
also significant. This new arrangement of the parts of the impact
mechanism provides the greatly increased impact forces previously
mentioned without significant increases in the overall size and
length of tool 101 as compared with prior art tools providing much
lower forces.
Head 20 advantageously comprises a holder or housing 70 which
mounts to end 18 of plunger 16 by screw threads or the like. Holder
70 includes two substantially parallel sides 72 having hooks or
flanges 74 on the bottom edges thereof extending toward each other.
Inserts 76 such as cutting devices, seating devices or combinations
thereof are removably inserted into the ends of holder 70 and held
therein by flanges 74 engaging grooves 78 or the like in inserts
76. Thus various inserts tailored for specific operations such as
seating or trimming conductors can be used in tool 101.
A pad 80 of resilient energy absorbing material such as neoprene
rubber is placed between insert 76 and the top of holder 70. This
pad absorbs excessive forces in certain applications of tool 101.
For example, tool 101 can be used to seat wires in both rigidly
mounted and flexibly mounted index strips. More energy is required
in the latter case because energy is absorbed by the flexing of the
index strip support. Accordingly, tool 101 is designed to provide
the required force level for the maximum expected deflection. If
tool 101 is subsequently used on a rigidly mounted index strip very
little energy would be absorbed by the index strip support.
Therefore, the tool's output force level would increase. This
excess force would then compress pad 80 absorbing the excess
energy, keeping the force at a safe level so as not to damage the
connector blocks. As an alternative, the output forces of tool 101
could be made adjustable by making the position of cap 8 within
housing 2 variable to thereby control the amount of compression of
spring 50 prior to the triggering by pin 12 on cap 8.
FIG. 2 is a perspective view of an insert for use in head 20 and
adapted for simultaneously seating five conductor pairs in the
index strip of the previously mentioned 88-type connector and also
adapted for pushing or mounting a five pair connector block onto
the index strip after the wires have been seated therein. Insert 76
includes a body 90 of material such as plastic having a groove 92
separating two sides 94. Mounting slots 96 on the outside of sides
94 are used for mounting insert 76 in holder 20 as shown in FIG. 1.
Pairs of fingers or flanges 98 extend from sides 94 toward each
other. When insert 76 is inserted over an index strip of an 88-type
connector, fingers 98 push the wires previously laid in the index
strip into the bifurcated terminals of the strip in response to the
impacting of plunger 16 by hammer 30. The connecting blocks used in
the 88-type connectors can also be held between fingers 98 and
seated or pushed onto the index strip upon the impacting of plunger
16. Fingers 98 can comprise an integral part of body 90 or can
comprise inserts mounted in body 90.
An insert 76 for simultaneously seating and trimming five pairs of
conductors as well as seating connecting blocks is shown in FIG. 3.
This insert is substantially the same as that shown in FIG. 2 with
the addition of cutters or blades 99 along the top edges of fingers
on one side of body 90. Cutters advantageously are metal inserts
which are isolated from each other to prevent any shorting between
wire pairs being trimmed. When wires have been seated in the index
strip by fingers they are essentially bottomed in the bifurcated
terminals so that cutters 99 can trim the ends of the wires
extending from one side of the index strip to a uniform length. The
impact mechanism of this invention provides sufficient force to
perform both the seating and trimming with a single stroke.
While the invention has been described with respect to specific
embodiments thereof, various modifications might be made thereto
without departing from its spirit and scope. For example, various
types of heads other than those illustrated could be configured so
that the tools would make operations easier and more efficient.
* * * * *