Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
INTRODUCTION
This invention relates to a tool for se~ting mandrel
rivets and more particularly to a hand tool which i5 manually
operated. This invention is an improvement upon the tool
shown in my earlier U.S. Patent No. 3,646,800 dated March 7,
1972 entitled ~Mandrel Rivet-Settlng Tool~
~ andrel rivets are widely used for securing together two
or more wor kpieces in situations where there is access to
only one side of the workpieces. These mandrel rivets are
constructed to have an elonyated mandrel affixed to a head in
a manner to permit the mandrel to be snapped off with the
application of a predetermined pulling f~rceO A short,
flanged tubular shank is positioned around the mandrel at the
head end~ ~hen the shank is inserted into aligned holes in
the workpieces to be joined and the mandrel is pulled away
from the head, the head spreads out the shank to lock the
workpieces bet~een the resulting flattened deformed end of
the shank and its flange, and then to snap off the mandrel
from the headO The mandrel is then removed from the tool and
discarded.
Sever~l types of tools have been developed for inserting
and actuating these mandrel rivets. (See, for example, U.S.
Patent Nos. 3,280,615; 3,324,700, 3,328,985, and,
3,399,5Sl). me purpose of the invention shown in my prior
patent No. 3,646,800 is to provide an improved tool which can
grip and hold a mandrel prior to inserting the rivet shank
into th~ workpieces, which can be constructed to provide
automatic ejection of the mandrel into a collector, and in
which the grip can be adjusted for different mandrel metals.
me object of the present invention is to provide a
further improved tool which is easier to operate, prevents
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pieces of the mandrel from becoming stuck in ~he body of the
tool, and is essentially self cleaning.
To accomplish these objects, this invention is
incorporated into the tool shown in my earlier patent,
supra. A spring is incorporated into the tool between the
handles, which biases them apart by overcoming the bias of
the spring incorporated into the tool body. Conseq~ently,
the jaws of the tool which are used to grip and pull the
mandrel are biased to the open position~ to prevent mandrel
parts from becoming stuck between them. Furthermore, when
the handles are released, the spring between them forces them
apart rapidly, and the vibration of the ~ool under this
action shakes loose any small particles between the jaws.
The open biased position also makes the tool easier fcr the
operator to use with one hand.
This invention accordingly comprises the features of
construction, combination of elements and arrangement of
parts which will be exemplified in the constructions
hereinafter described and the scope of the inven~ion will be
indicated in the claims.
- For a fuller understanding of the nature and objects of
the invention, reference should be had to the following
detailed description taken in connection with the
accompanying drawings in which:
BRIEF FIGURE D SCRIPTION
FIG. 1 is a side view of the tool of this invention shown
in its biased or open position;
FIGo 2 is an end view of the tool;
FIG. 3 is a cross section of ~he rivet-holding end of the
frame;
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FIG~ 4 is a cross section of that portion of the tool
where the frame and act~ating handle are joined for pivotal
movement taken along line 4-4 of FIG. l;
FIG~ 5 is an enlarged, detailed cross section of one
embodimerlt of the rivet holding and actuating mechanism
showing the tool in the biased position and with the mandrel
of the rivet in place in the body;
FIG. 6 shows the mechanism oP FIG. 5 in its
mandrel-gripping and pulling position;
FIGS. 7 and 8 are perspective and cross-sectional views
of one of the jaws used in gripping;
FIG. 9 is a top planar view of a pair of the jaws;
FIG. 10 is a fragmentary cross section of another
embodiment of the rivet-holding and actuating mechanism using
a threaded ring to adjust the compression of the spring;
FI~. 11 is a top planar view of the ring in FIG. 10;
FIG. 12 illustrates the incorporation of a mandrel
collector in the embodiment of FIG. 10; and
FIG. 13 is a fragmentary cross section of another
embodiment of the rivet-holding and actuating mechanism
having means for adjusting the compression of the spring and
mandrel collecting means.
DETAILED DESCRIPTION
The hand tool of this invention is shown in side and end
views in FIGS. 1 and 2. With the exception of the main
spring between the handles and the facility for securing the
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spring in place, the tool i5 the same as in my earlier patent
No. 3,646,800. The tool will be seen to be formed of a frame
10, an actuating handle 11 and a rivet-gripping and pulling
echanism 12. The frame 10 and actuating handle 11 are
joined for pivotal motion with respect ~o each other, and the
rivet-gripping and pulling mechanism 12 is joined to the
actuating handle 11 ~or axial motion within the frame 10.
The frame 10 comprises a forward head section 15, a
fulcrum extension member 16 having an opening 17 for a
bushîng and a flat stop member 18, and an elongated curved
finger-engaging handle 19 which may be partially covered with
a sheath 20 having a good gripping surface. The actuating,
palm-engaging handle 11 comprises a forward section 25 which
is bifulrcated into two arms 26 and 27 between which the
fulcrum extension member 16 is positioned. Actuating handle
11 has a curved gripping end 30 which begins with an enlarged
section 31 and is covered by a sheath 32 having a good
gripping surface. The combination of the curved handles, the
upper of which has the enlarged section 31, results in a
comfortable ~rip for the user while maintaining his hand in
the proper position. Threaded bores are provided along the
top of the actuating handle for carrying anvils such as 34,
35 and 36 of various bore diameters.
The pivotal connection between the finger-engaging handle
10 and the actuating handle 11 is made through a pivot pin 4 0
(see FIG. 4) which is positioned within a bushing 41, located
in opening 17, and in two flanged bushings 42 and 43 located
in appropriately sized openings in arms 26 and 27. The pin
is locked with s~itable ~nap rings 44 to prevent its axial
30 movement~
The handles 11 and 19 are biased apart by a main spring S
which lies between the handles and is supported in place as
shown in FI~. 1. This arrangement is described in greater
de~ail below.
A chamber 51 is defined within the head sec~ion of the
frame (FIG. 3). ~mis chamber is of a configuration which
permits axial movement of the cylindrical mandrel-gripping
and pulling mechanism 12. The chamber 51 is open at the top
and has a threaded opening 52 at what may be termed the
muz~le end of the head 15. miS threaded opening is adapted
to receive a threaded anvil 33, as will be subsequently
explained. The lower portion of the chamber has a
frustoconical conf iguration 53 defined by a slanting wall 54.
FIG. 5 is a detailed cross section of the
mandrel-gripping and pulling mechanism in position to receive
the mandrel, i.e., with the actuating arm 11 in its biased
position pivoted to achieve maximum spacing from the
finger-engaging handle which means that the mandrel-gripping
and pulling mechanism 12 is in its lowermost positiun. In
this condition, the mandrel of the rivet may be readily
inserted. Then by squeezing the handles 11 and 19 together
through a small arc in overcoming the bias of spring S the
mandrel is held firmly in the tool, permitting the tool to be
used as the means for introducing the rivet head and shank
into the holes of the workpieces. This ability of the tool
to hold the mandrel means that the rivets may be easily used
for joining workpieces which would normally be in an awkward
location if the rivet had to be hand-held in place until the
tool was brought into position.
In FIG. 5 in which like tool components are identified by
like reference numerals used in FIGS. 1-4, the rivet is seen
positioned with respect to two workpieces 58 and 59 which are
to be joined~ The rivet is comprised of a mandrel 60 which
terminates in a head 61 which is joined to i~ in a manner to
require a predetermined amount of force to break them apart.
A tubular shank 62 having a flange 63 is slipped over the
mandrel and at~ached to the head. As the mandrel is pulled,
it causes the head to deform and flatten out the shank, thus
locking the workpieces 58 and 5g together be~ween the flange
and deformed and flattened side of the shankO
The mandrel-gripping and pulling mechanism is contained
within a sleeve 65 which defines an actuator bore 66. The
sleeve 659 at its upp2r end is pivotally mounted to arms 26
and 27 by means of pivot pins 67 and 68 whirh are partially
threaded for screwing into the arms and being locked
~hereto. In the embodiment of FIGS. 5 and 6, these pivot
pins extend through the sleeve wall and into the a~tuator
bore to serve as spring retaining means as described belowO
The sleeve has a generally frustoconical configuration at its
lower end. me outer surface 70 ~FIG. 6) of this lower part
of the sleeve essentially corresponds to the frustoconical
con~iguration o~ slanting wall 54 of the inner wall of
chamber 51. The lower inner wall 72 of the sleeve is also of
a frustoconical configuration, the angle which it forms with
the central axis of the sleeve being smaller than that formed
by the outer surface 70. Since the sleeve must ride up and
down on the conical surface 73 of the anvil 33 the lower edge
74 of the sleeve is cut a~ an angle to provide a surface
which makes contact with anvil surface 73.
The anvil 33 is threaded for engagement with the threads
of opening 52, and it has a bore 75 sized to permit the
mandrel 60 of the rivet to be passed through it. The anvils
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34, 35 and 36 have bores of varying diame~ers ~o accommodate
different sized mandrels. They are, of course, readily
interchangeableO
The mandrel is gripped between two essentially
semicircular jaw pieces 78 which are detailed in FIC~ 7, 8
and 9. ~hen assembled .in the sleeve as in FIGS. S and 6, the
jaw pieces form an essentially frustoconical configuration
corresp~nding essentially to that def ined by ~he inner wall
72 of the lower section of the sleeve and def ine between them
a threaded or serrated mandrel-gripping channel 80. Each,
essentially semicircular jaw piece i5 CUt to have a major
upper planar surface 81 which slants downwardly toward the
cen~ral axis of ~he channel. It is preferred that this major
upper planar surface 81 be intersected by a minor planar
surface 82 which approaches 90~ with the plane of the cen~ral
axis. The presence of the minor planar surface 82 eases the
opening of the jaws when a force is applied to the planar
surface 81. In a similar manner the lower jaw pieces are cut
to have a major lower planar surface 83 which slants upwardly
~0 toward the central axis of the channel and which is
intersected by a minor planar surface 84 which may slant in
the same manner but at a lesser angle which approaches 90
with the plane of the central axis. me angle at which the
major planar surface is cut is chosen so as to achieve
contact between ~he planar surface 83 and the conical surface
77 of the anvil against which it ridesO The minor planar
surfac~ 84 serves the same general purpose as the minor
planar surface 82.
A jaw actua~or member 88 in actuator bore 51 is
positioned to apply force through contact of its inclined
lower surface 8~ with the major planar surfaces 81 of the
jaws. This actuator member has a bore 90 running throughout
i~s length, this bore being of a diameter such as to permit
passage of the largest sized mandrels 60. The upper surface
91 of the jaw actuator member and ~hose portions of the pivot
pins 67 and 68 which extend into the actuator bore serve as
means to retain the compression spring 92 in force applying
relationship to the jaw actuator memher and through it to the
j aws.
The coil spring S is shown in FIG. 1 to be supported at
its lower end on the boss 100 formed on the handle 19 of
frame 10. The boss extends into the lower ~urn of the coil
spring S. A second boss 102 is provided in a recess 104
formed on the bottom of handle 11. The boss 102 like boss
100 fits into the end turn of the coil spring S. me maximum
spread of the handles is limited by the maximum depth sleeve
6S may penetrate into chamber 51 in the head 15. In that
position, the coil spring S is under compression and
therefore it remains on the bosses 100 and 104 and holds the
sleeve at its lowermost position. At the same time, spring
92 drives the actuator member 88 downwardly, as viewed in
FIG. 5 to hold jaw pieces 78 in the open position.
In operation, when the actuating handle 11 is in the
biased position raised upwardly from handle 10, sleeve 65 is
moved downwardly to the position illustrated in FIG. 5.
Force applied by spring 92 through jaw actuator 88 maintains
the jaws in contact with sleeve surface 72 and anvil surface
73. In this position, the jaws are spread out, the gripping
channel 80 is widened and the mandrel slips reaaily into
place as shown in FIG. 5. The application of slight pressure
to squeeze handles 11 and 19 together raises the slee~e 65
sufficiently to cause the jaws to lock the mandrel and the
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rivet in place. This ~loaded" position prior ~o insertion of
the shank of the rivet into the workpieces is a condition
intermedizte between the two positions shown in FIGSo 5 and 6.
When ~he rivet is to be set, pressure is applied to
handle 11 to overcome the coil spring S~ causing the handle
11 to pull the sleeve 65 with respect to the frame, and
causing the jaws to grip the mandrel. This results first in
deforming the shank to a somewhat flattened state 64 and ~hen
in snapping the mandrel from the head. mrough proper
alig~ment of the fulcrum locus (pivot pin 40) with respect to
the pivot axis of pivot pins 67 and 68, the mandrel-pulling
mechanism withdraws the mandrel in an essentially straight
condition. mi5 in turn means that the mandrel is easily
removed either by permitting it to fall out of the tool or by
automatically discharging it into a mandrel collector. Stop
18 limits the ex~ent to which the handles may be forced
toward each other, thus preventing injury to fingers which
might be caught between the handles. The rivet mandrel may
be then removed through the anvil bore or through the top of
the sleeve.
It may be advantageous to be able ~o adjust, in any one
tool, the amount of force which is applied by the jaws in
~ripping the mandrel. Thus if the mandrel is made of
aluminum, this force is desirably less than if it is formed
of, say, stainless s~eel or some other harder metal. ~n the
case of a relatively ~soft" metal such a~ aluminum it is
desirable ~o use less force to minimize the buildup of metal
in the serrations of the jaws. Excessive metal buildup in
these serrations requires that the jaws be replaced. In the
case of the harder metals~ it is of course necessary to apply
more force to assure gripping of the mandrel. The tool
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modifications illustrated in FIGSo 10~13 provide means for
adjus~ing ~he gripping force in addition ~o the in~erchanging
of springs o various compressive strengths.
ln FIG~ 10, in which like reference numerals are used to
identify like components in FIG. 5, the upper
spring retaining means is a threaded ring 95 adapted to
engage threads 96 cut within the inner wall of sleeves 65.
The position of ring 95 may be used to exert more or less
compressive force on spring 92. me ring must have some way
to engage a screwing mechanism for locating it into îts
desired position, such as notches 97 ~FIG. 11). me pivot
pins 67 and 68 may terminate within the sleeve wall as shown
since they are not used as a spring-retaining means as in
FIG. 5.
FIG. 12 illustrates the use of the ring 95 to adjust the
gripping strength and the incorporation of a rivet collector
100 which for convenience may be joined to or integral with
the ring 9S. In using tools to set rivets of the type
described it is usually customary to permit the mandrels to
fall ou~ of the tool into the work area. This is highly
undesirable from the point of view of personal safety for
they can cause serious falls when stepped on~ m e collection
100 of FIG. 12 prevents such hazards and may be used in one
of two different modes. If a spring is used which has normal
compressive strength, the mandrel may be collected by merely
turning the tool over to permit ~he mandrel to fall freely
into collector 100. The second proper location mode of
operation is based upon the use of a weaker spring which,
when the mandrel is snapped from the head, causes the mandrel
to be impelled into the collector 100. The relative strength
o~ the spring may be adjusted by the proper location of the
ring.
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In the modification of FIG. 13, the pivot pins extend
into the sleeve as in FIG. 13. These pins are used to engage
one of a series of grooves 101, 102 and 103 in a ring member
104 which is adapted ~o fit into the sleeve an~ serve as the
spring retaining means. By engaging the proper groove, a
predetermined force is applied to the spring. There may~ of
course, be any number of grooves or holes, and the ring 104
may be attached to or integral with a mandrel collector 105.
Coil spring S, by forcing the sleeve 65 forward, in
cooperation with the action of ~he spring 92, assures that
the jaw pieces open immediately upon release of pressure upon
the handles. Consequently, no portion of the mandrel will
become lodged in the head which may interfere with subsequent
use of the tool. Furthermore, the strength of spring S is
such that the handles are rapidly spread apart under its
influence, and the sleeve 65 therefore moves rapidly in the
head and jars the jaw pieces and other parts o the tool.
The resulting vibra~ion tends ~o shake loose any particles on
the jaw pieces which may cause wear of the jaws. As a
result, it is unnecessary to clean the interior of the tool
as frequently as would otherwise be necessary. As yet
another advantage, the automatic opening of the jaws
eliminates the need for the user to operate the tool with two
hands or awkwardly manipulate the fingers of one hand in
order ~o open the tool for its next application. It should
also be appreciated that the spring S may be incorporated
into t~e tool structure without appreciably raising the tool
costO These advanta~es are significant benefits derived from
the present invention.
It will thus be seen that the objects set forth above,
among those made apparent from the preceding description, are
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efficiently a'ctained, and~ since certain chanyes may be made
in the above apparatus without departing from ~he scope of
the invention, it is intended 'cha'c all matter contained in
th~ above description or shown in the accompanying drawin~s
~hall be interpreted as illustrative and not in a limiting
sense .
