Title: Honeycomb rivet
Abstract: The invention provides a rivet and method of installing the rivet to attach honeycomb material to other materials. The rivet is installed by drilling a hole through the materials. A back side sleeve of the rivet is inserted through one end of the hole while a front side sleeve with a stem member inserted therethrough is inserted through the other end of the hole such that the head of the stem member and the sleeve portion of the front sleeve are positioned within the sleeve portion of the back sleeve. The shank portion of the stem member is then pulled such that the head of the stem member expands the sleeve portions of the front and back sleeves into the materials to attach the rivet to the materials. A locking collar is also provided to lock the stem member to the front sleeve upon continued pulling of the stem member.
Patent Number: 6,898,918 Issued on 05/31/2005 to Eshraghi
| Inventors:
|
Eshraghi; Soheil (Irvine, CA)
|
| Assignee:
|
Textron Inc. (Providence, RI)
|
| Appl. No.:
|
358863 |
| Filed:
|
February 5, 2003 |
| Current U.S. Class: |
52/787.1; 52/364; 52/376; 52/377; 52/404.2; 52/406.1; 52/406.2; 52/406.3; 52/483.1; 52/783.1; 52/791.1; 156/73.1; 156/73.5; 156/293; 411/34; 411/41; 411/42; 411/43; 411/338; 411/339 |
| Intern'l Class: |
E04C 002/54 |
| Field of Search: |
52/7871,483.1,791.1,783.1
411/43,338,339,34
|
References Cited [Referenced By]
U.S. Patent Documents
| 3593248 | Jul., 1971 | Shepherd et al.
| |
| 3771410 | Nov., 1973 | Swindt, II.
| |
| 3937123 | Feb., 1976 | Matuschek et al.
| |
| 4012984 | Mar., 1977 | Matuschek.
| |
| 4122753 | Oct., 1978 | Kuhlmann et al.
| |
| 4251916 | Feb., 1981 | Linden.
| |
| 4432679 | Feb., 1984 | Angelosanto et al.
| |
| 4436467 | Mar., 1984 | Larsson et al.
| |
| 4490083 | Dec., 1984 | Rebish.
| |
| 4678384 | Jul., 1987 | Sparling et al.
| |
| 4784551 | Nov., 1988 | Kendall.
| |
| 4826378 | May., 1989 | Pamer et al.
| |
| 4844673 | Jul., 1989 | Kendall.
| |
| 4949450 | Aug., 1990 | Scharres.
| |
| 5275529 | Jan., 1994 | Langenbrunner et al.
| |
| 5536344 | Jul., 1996 | van Dreumel.
| |
| 5658107 | Aug., 1997 | Smith.
| |
| 6077009 | Jun., 2000 | Hazelman.
| |
| 6537005 | Mar., 2003 | Denham.
| |
Other References
Cherry Maxibolt blind bolt catalog © 1990 by Textron Aerospace Fasteners,
8 pages.
Cherrymax Rivet (U.S. Appl. No. 4,012,984) catalog © 2000 by Textron Aerospace
Fasteners, 31 pages.
Cherrymate Fastening Systems Product Information © 1997 Avdel Cherry Textron
Inc., 2 pages.
|
Primary Examiner: Friedman; Carl D.
Assistant Examiner: Green; Christy M.
Attorney, Agent or Firm: Trexler, Bushnell, Giangiorgi, Blackstone & Marr, Ltd.
Parent Case Text
CROSS-REFERENCE
This patent application claims the benefit of domestic priority of U.S. Provisional
Application Ser. No. 60/359,497, filed Feb. 25, 2002, and entitled "Honeycomb Rivet".
Claims
1. A fastener for attaching honeycomb material to a workpiece, the honeycomb
material and the workpiece defining a hole, said fastener comprising:
a back side sleeve adapted for insertion in the hole, said back side sleeve having
an aperture extending at least partially therethrough;
a front side sleeve adapted for insertion in the hole, said front side sleeve
having an aperture extending entirely therethrough, at least a portion of said
front side sleeve configured such that said portion is positionable withen said
aperture of said back side sleeve; and
a stem member having a stem head and a shank extending therefrom, said shank
being positioned within said aperture of said front side sleeve, said stem head
being positioned within said aperture of said back side sleeve, said stem member
configured such that said stem head expands said front side sleeve upon said stem
head being pulled into said aperture of said front side sleeve, said expansion
of said front side sleeve causing expansion of said back side sleeve such that
said front and back side sleeves lock together and attach said fastener to the
honeycomb material and the workpiece.
2. A fastener as defined in claim 1, wherein said back side sleeve has a head
at a first end thereof and a sleeve portion which extends from said head to a second
end thereof, said head of said back side sleeve being configured such that said
head is incapable of passing through the hole, said aperture of said back side
sleeve extending from said second end of said back side sleeve toward said first
end of said back side sleeve, and wherein said front side sleeve has a head at
a first end thereof and a sleeve portion which extends from said head to a second
end thereof, said head of said front side sleeve being configured such that said
head is incapable of passing through the hole, at least a portion of said sleeve
portion of said front side sleeve configured such that said portion is positionable
within said aperture of said sleeve portion of said back side sleeve.
3. A fastener as defined in claim 2, further including means for locking said
stem to said front side sleeve.
4. A fastener as defined in claim 3, wherein said locking means includes a locking
collar positioned between a lock groove provided in said stem and said sleeve portion
of said front side sleeve, said locking means further including a driving anvil
positioned around said stem, said driving anvil configured such that said driving
anvil blocks movement of said locking collar such that said locking collar deforms
within said lock groove and said aperture of said front side sleeve when said locking
collar contacts said driving anvil upon said aperture of said front side sleeve
upon said stem head being pulled into said aperture of said front side sleeve,
said deformation of said locking collar locks said stem to said front side sleeve.
5. A fastener as defined in claim 4, wherein a diameter of said aperture of said
front side sleeve is larger within said head thereof than a diameter of said aperture
of said front side sleeve within said sleeve portion thereof such that said locking
collar is capable of deforming into said aperture of said front side sleeve.
6. A fastener as defined in claim 4, said stem is provided with a weakened part
with spacing between said weakened part and said stem head being within a grip
length of the fastener whereby said stem is configured such that said weakened
part breaks when the deforming of said locking collar stops the movement of said stem.
7. A fastener as defined in claim 6, wherein said weakened part is a break groove
spaced from said locking groove, said locking collar fitting slidably in said front
side sleeve and overlapping said break groove.
8. A fastener as defined in claim 4, wherein said stem is configured such that
said stem is grippable by a setting tool to receive a tensile force as a reaction
to a compressive force is applied to said driving anvil.
9. A fastener for attaching honeycomb material to a workpiece, the honeycomb
material and the workpiece defining a hole, said fastener comprising:
a back side sleeve adapted for insertion in the hole, said back side sleeve having
an aperture extending at least partially therethrough, said back side sleeve has
a head at a first end thereof and a sleeve portion which extends from said head
to a second end thereof, said head of said back side sleeve being configured such
that said head is incapable of passing through the hole, said aperture of said
back side sleeve extending from said second end of said back side sleeve toward
said first end of said back side sleeve;
a front side sleeve adapted for insertion in the hole, said front side sleeve
having an aperture extending entirely therethrough, at least a portion of said
front side sleeve configured such that said portion is positionable within said
aperture of said back side sleeve, said front side sleeve has a head at a first
end thereof and a sleeve portion which extends from said head to a second end thereof,
said head of said front side sleeve being configured such that said head is incapable
of passing through the hole, at least a portion of said sleeve portion of said
front side sleeve configured such that said portion is positionable within said
aperture of said sleeve portion of said back side sleeve;
a stem member having a stem head and a shank extending therefrom, said shank
being positioned within said aperture of said front side sleeve, said stem head
being positioned within said aperture of said back side sleeve, said stem member
configured such that said stem head expands said front side sleeve upon said stem
head being pulled into said aperture of said front side sleeve, said expansion
of said front side sleeve causing expansion of said back side sleeve such that
said front and back side sleeves lock together and attach said fastener to the
honeycomb material and the workpiece; and
means for locking said stem to said front side sleeve, said locking means includes
a shifting washer having a first washer element and a second washer element, said
washer elements being concentrically arranged but axially offset from each other,
said washer elements being joined together by a shear section, said first washer
element being of a size so as to freely slidably fit within an internal dimension
of said second washer element upon shear of said shear section, and a locking collar
initially separate from both said washer elements and from said second sleeve underlying
said second washer element and being engageable by said second washer element as
a result of and upon said breakaway portion responding to said maximum force to
be forced by said radially inner element into cooperating means on said stem and
said front side sleeve to lock said stem and said front side sleeve in their respective
positions.
10. A fastener as defined in claim 9, wherein a diameter of said aperture of
said front side sleeve is larger within said head thereof than a diameter of said
aperture of said front side sleeve within said sleeve portion thereof such that
said locking collar is configured to deform into said aperture of said front side sleeve.
11. A fastener as defined in claim 9, said stem is provided with a weakened part
with spacing between said weakened part and said stem head being within the grip
length of the fastener whereby said stem is configured such that said weakened
part breaks when the deforming of said locking collar stops the movement of said stem.
12. A fastener as defined in claim 11, wherein said weakened part is a break
groove spaced from said locking groove, said locking collar fitting slidably in
said front side sleeve and overlapping said break groove.
13. A fastener as defined in claim 9, wherein said stem is adapted to be gripped
by a setting tool to receive a tensile force as a reaction to a compressive force
is applied to said shifting washer.
14. A fastener comprising:
a back side sleeve having a head at one end and an expandable sleeve portion
at an opposite end, said expandable sleeve portion having an aperture therein;
a front side sleeve having a head portion at one end and a sleeve portion at
an opposite end, said sleeve portion of said front side sleeve configured to be
positionable within said aperture of said sleeve portion of said back side sleeve,
said front side sleeve having an aperture extending therethrough;
a stem member having,
a head portion at an end thereof, said head portion configured to be positionable
within said aperture of said back side sleeve, said head portion further being
configured to be pulled into said aperture of said front side sleeve such that
said sleeve portion of said front side sleeve is expanded, said expansion of said
front side sleeve in turn expands said sleeve portion of said back side sleeve
such that said back side sleeve and said front side sleeve are joined together,
a shank extending from said head portion to an opposite end thereof, said shank
configured to be substantially positionable within said aperture of said front
side sleeve, said shank having a pulling portion at said opposite end which is
adapted to be engaged by a tool for pulling said stem member.
15. A fastener as defined in claim 14, further including means for locking said
stem to said front side sleeve.
16. In combination:
honeycomb material having a first honeycomb skin having inner and outer surfaces,
a second honeycomb skin having inner and outer surfaces, and a honeycomb interior
provided between said inner surfaces of said first and second honeycomb skins,
said honeycomb material having an aperture therethrough;
a first workpiece positioned against said outer surface of said first honeycomb
skin, said first workpiece having an aperture therethrough which is in alignment
with said aperture of said honeycomb material;
a second workpiece positioned against said outer surface of said second honeycomb
skin, said second workpiece having an aperture therethrough which is in alignment
with said aperture of said honeycomb material; and
a fastener having,
a back side sleeve positioned within said aperture of said first workpiece and
at least partially positioned within said aperture of said honeycomb material,
said back side sleeve having an aperture extending partially therethrough, at least
a portion of said back side sleeve being radially expanded in said aperture of
said honeycomb material to in that manner firmly secure said back side sleeve to
said honeycomb material; and
a front side sleeve positioned within said aperture of said second workpiece
and at least partially positioned within said apertures of said honeycomb material
and said back side sleeve, said front side sleeve having an aperture extending
therethrough, at least a portion of said front side sleeve being radially expanded
in said aperture of said back side sleeve to in that manner firmly secure said
front side sleeve to said back side sleeve.
17. The combination of claim 16, wherein said fastener further includes a stem
member and means for locking said stem member to said front side sleeve, said stem
member having a head portion and a shank portion extending therefrom, said head
portion being positioned within said aperture of said front side sleeve proximate
to said radially expanded portion of said front side sleeve.
18. The combination of claim 17, wherein said first and second workpieces have
counterbores provided therein which are in communication with said apertures of
said first and second workpieces, and wherein said front and back side sleeves
have head portions, said head portion of said back side sleeve being positioned
within said counterbore of said first workpiece, said head portion of said front
side sleeve being positioned within said counterbore of said second workpiece.
19. The combination of claim 18, wherein said locking means is provided between
said head portion of said front side sleeve and said shank portion of said stem member.
20. A method of attaching first and second workpieces to honeycomb material,
the honeycomb material having a first honeycomb skin, a second honeycomb skin,
and a honeycomb interior therebetween, said honeycomb material having an aperture
therethrough, the first workpiece having an aperture therethrough, the second workpiece
having an aperture therethrough, the method comprising the steps of:
a) positioning the first workpiece against the first honeycomb skin to align
the apertures of the first workpiece and the honeycomb material;
b) positioning the second workpiece against the second honeycomb skin to align
the apertures of the second workpiece and the honeycomb material;
c) inserting a back side sleeve through the aperture of the first workpiece and
into the aperture of the honeycomb material, the back side sleeve having an aperture
extending at least partially therethrough;
d) inserting a stem member through an aperture of a front side sleeve, the aperture
of the front side sleeve extending entirely therethrough, the stem member having
a head portion and an shank extending therefrom, the head portion being positioned
outside of the aperture of the front side sleeve;
e) inserting the front side sleeve through the aperture of the second workpiece,
into the aperture of the honeycomb material, and into the aperture of the back
side sleeve such that the head portion of the stem member is positioned within
the aperture of the back side sleeve;
f) pulling the shank portion of the stem member such that the head portion of
the stem member enters the aperture of the front side sleeve and expands the front
side sleeve and, thus, the back side sleeve, such that the front and back side
sleeves are attached together, and such that the back side sleeve and the honeycomb
material are attached together; and
g) locking the front side sleeve and the elongated shank portion of the stem
member together.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a fastener for fastening honeycomb materials
to other structures without damage to the honeycomb itself.
Honeycomb materials are used extensively within the aircraft construction
business and are attached to other materials, such as sheets of metal, to hold
the structure of the aircraft together. Presently there are only a few fasteners
which are designed for attaching honeycomb materials to other materials to hold
the structure of the aircraft together. A number of disadvantages, though, have
arisen in the use of these fasteners. For instance, these fasteners are very expansive
and cumbersome to install, thus requiring a lengthy installation process.
Thus, there is a need for a fastener for attaching honeycomb materials to other
materials to hold the structure of an aircraft together which overcomes the disadvantages
of the prior art fastener designs. The present invention provides for such a fastener design.
OBJECTS AND SUMMARY OF THE INVENTION
A primary object of the invention is to provide a rivet for fastening honeycomb
materials to other materials which is quick and easy to install in comparison to
other fasteners currently used for the same purpose.
Another object of the invention is to provide a honeycomb rivet which is
reliable in attaching honeycomb materials to other materials.
Another object of the invention is to provide a honeycomb rivet which is
capable of attaching honeycomb materials to other structures without damage to
the honeycomb itself.
Yet another object of the invention is to provide a honeycomb rivet which can
be used in large thicknesses of materials.
Still another object of the invention is to provide a honeycomb rivet which
clamps tightly and securely without crushing the honeycomb materials or the structures
which the honeycomb materials attach to.
Another object of the invention is to provide a honeycomb rivet which only
needs a single uniform size hole to be drilled through the honeycomb material and
the structures to be attached thereto, for the honeycomb rivet to effectively attach
the honeycomb material to the structures.
Still another object of the invention is to provide a hole for the honeycomb
rivet to be inserted into which is not tight, thus allowing easy insertion of the
honeycomb rivet within the hole prior to the attachment of the honeycomb rivet
to the honeycomb materials and the structures to be attached thereto.
Briefly, and in accordance with the foregoing, the invention provides a
honeycomb rivet and method of installing the honeycomb rivet to attach honeycomb
material to a desired structure. A rivet is installed by drilling a hole through
the materials. A back side sleeve of the rivet is inserted through one end of the
hole while a front side sleeve with a stem member inserted therethrough is inserted
through the other end of the hole such that the head of the stem member and the
sleeve portion of the front sleeve are positioned within the sleeve portion of
the back sleeve. The shank portion of the stem member is then pulled such that
the head of the stem member expands the sleeve portions of the front and back sleeves
into the materials to attach the rivet to the materials. A locking collar is also
provided to lock the stem member to the front sleeve upon continued pulling of
the stem member.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the invention which are believed to be novel are described in
detail hereinbelow. The organization and manner of the structure and operation
of the invention, together with further objects and advantages thereof, may best
be understood by reference to the following description taken in connection with
the accompanying drawings wherein like reference numerals identify like elements
in which:
FIG. 1 is a cross-sectional, side-elevational view of a back side sleeve of
a honeycomb rivet of both a first and second embodiments of the invention;
FIG. 2 is a cross-sectional, side-elevational view of a front side sleeve of
the honeycomb rivet of both the first and second embodiments;
FIG. 3 is a side-elevational view of an elongated stem of the honeycomb rivet
of both the first and second embodiments;
FIGS. 4-7 are cross-sectional views of a first embodiment of a honeycomb rivet
of the present invention illustrating the attachment of the honeycomb rivet to
a workpiece; and
FIGS. 8-11 are cross-sectional views of a second embodiment of the honeycomb
rivet of the present invention illustrating the attachment of the honeycomb rivet
to a workpiece.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT
While this invention may be susceptible to embodiment in different forms, there
is shown in the drawings and will be described herein in detail, specific embodiments
with the understanding that the present disclosure is to be considered an exemplification
of the principles of the invention, and is not intended to limit the invention
to that as illustrated.
A first embodiment of a honeycomb rivet
100 is shown in FIGS. 1-7 and a
second embodiment of the honeycomb rivet
300 is shown in FIGS. 8-11. Like
elements are denoted with like reference numerals with the first embodiment being
in the one and two hundreds, and the second embodiment being in the three and four hundreds.
Attention is now directed to the honeycomb rivet
100 of the first
embodiment of the invention as illustrated in FIGS. 1-7. The honeycomb rivet
100
of the first embodiment includes a back side sleeve
102, a front side sleeve
104, a stem member
106, an internal locking collar
108, and
a driving anvil
110.
As best illustrated in FIG. 1, the back side sleeve
102 of the honeycomb
rivet
100 has a head portion
112 and a sleeve portion
114.
The head portion
112 is positioned at a first end
116 of the back
side sleeve
102 and the sleeve portion
114 extends from the head
portion
112 of the back side sleeve
102 to a second end
118
of the back side sleeve
102. The head portion
112 at the first end
116 of the back side sleeve
102 has an outer diameter D
1.
From the first end
116 of the back side sleeve
102, the head portion
112 tapers inwardly to the sleeve portion
114. The sleeve portion
114 has a uniform outer diameter D
2, which is smaller than the diameter D
1.
The sleeve portion
114 has an aperture
120 therein which extends
from the second end
118 of the back side sleeve
102 toward the first
end
116 of the back side sleeve
102, but does not extend the entire
length of the sleeve portion
114. The aperture
120 within the sleeve
portion
114 has a diameter D
3, which is smaller than the diameter D
2.
As best illustrated in FIG. 2, the front side sleeve
104 of the honeycomb
rivet
100 has a head portion
122 and a sleeve portion
124.
The head portion
122 is positioned at a first end
126 of the front
side sleeve
104 and the sleeve portion
124 extends from the head
portion
122 of the front side sleeve
104 to a second end
128
of the front side sleeve
104. The head portion
122 at the first end
126 of the front side sleeve
104 has an outer diameter D
4.
Outer diameter D
4 is preferably equivalent to outer diameter D
1.
From the first end
126 of the front side sleeve
104, the head portion
122 tapers inwardly to a first end
130 of a first portion
132
of the sleeve portion
124. The first portion
132 of the sleeve portion
124 has an outer diameter D
5. Outer diameter D
5 is preferably
equivalent to outer diameter D
2 and is smaller than diameter D
4.
A second end
134 of the first portion
132 of the sleeve portion
124
tapers inwardly to a first end
136 of a second portion
138 of the
sleeve portion
124. The second portion
138 of the sleeve portion
124 has an outer diameter D
6. Outer diameter D
6 is preferably
slightly smaller than diameter D
3. The purpose of this configuration of
the front side sleeve
104 will be discussed further herein.
The front side sleeve
104 has an aperture
140 extending therethrough
which extends from the second end
128 of the front side sleeve
104,
which is also a second end
142 of the second portion
138 of the sleeve
portion
124, to the first end
126 of the front side sleeve
104.
The aperture
140 has a first portion
144, a second portion
146
and a third portion
148. The first portion
144 of the aperture
140
is positioned at the first end
126 of the front side sleeve
104 and
has a diameter D
7. The first portion
144 of the aperture
140
extends within the head portion
122 of the front side sleeve
104.
Proximate to the first end
126 of the front side sleeve
104, a wall
150 of the aperture
140 of the first portion
144 tapers inwardly
to the second portion
146 of the aperture
140. The second portion
146 of the aperture
140 has a diameter D
8. Diameter D
8
is smaller than diameter D
7. The second portion
146 of the aperture
140 extends from within the head portion
122 of the front side sleeve
104 to the second end
134 of the first portion
132 of the
sleeve portion
124. The third portion
148 of the aperture
140
extends the entire length of the second portion
138 of the sleeve portion
124 and has a diameter D
9, which is larger than diameter D
8.
As diameter D
9 is larger than diameter D
8, an aperture shoulder
152
is provided within the aperture
140 between the second and third portions
146,
148 of the aperture
140.
As best illustrated in FIG. 3, the stem member
106 includes an enlarged
stem head
154 at a first end
156 of the stem member
106 and
an elongated shank
158 extending therefrom. The enlarged stem head
154
has a diameter D
10 which is slightly smaller than the diameter D
3
of the aperture
120 of the back side sleeve
102. The enlarged stem
head
154 tapers inwardly to a first portion
160 of the elongated
shank
158 which has a diameter D
11, which is smaller than the diameter
D
10 and slightly smaller than the diameter D
9 of the aperture
140
at the third portion
148 of the front side sleeve
104.
A second portion
162 of the elongated shank
158 extends from the
first portion
160 of the elongated shank
158. The second portion
162 has a diameter D
12 which is smaller than the diameter D
11,
such that a shoulder
164 is provided between the first and second portions
160,
162 of the elongated shank
158. The diameter D
12
is slightly smaller than the diameter D
8 of the aperture
140 at the
second portion
146 of the front side sleeve
104.
A third portion
166 of the elongated shank
158 extends from the
second
portion
162 of the elongated shank
158. The third portion
166
has a diameter D
13 which is smaller than the diameter D
12, such that
a shoulder
168 is provided between the second and third portions
162,
166 of the elongated shank
158.
The third portion
166 of the elongated shank
158 has an annular
lock groove
170 formed therein proximate to the shoulder
168 and
the second portion
162 of the elongated shank
158. The third portion
166 of the elongated shank
158 also has a pulling portion
172
proximate to a second end
174 of the stem member
106 and distal to
the shoulder
168 and the second portion
162 of the elongated shank
158. The third portion
166 is provided with a plurality of annular
pull grooves
176 so that it can be gripped by a conventional pull type or
setting tool
178. Such tools are well known in the art and, therefore, the
details thereof have been omitted for purposes of brevity and simplicity. The third
portion
166 further includes a break notch
179 between the annular
lock groove
170 and the pulling portion
172, but proximate to the
annular lock groove
170.
As best illustrated in FIG. 4, the internal locking collar
108 has a locking
boss
180 of increased thickness which fits into the annular lock groove
170. A reduced thickness lock sleeve portion
182 of the internal
locking collar
108 extends toward the second end
174 of the stem
member
106 along the third portion
166 of the elongated stem shank
158. The internal locking collar
108 is of a uniform cylindrical
configuration such that the third portion
166 of the elongated stem shank
158 with the internal locking collar
108 positioned thereon has a
diameter which is preferably the same size as diameter D
12 of the second
portion
162 of the elongated stem shank
158. The internal locking
collar
108 is preferably formed of a cold deformable material such as precipitation-hardening
stainless steel, for instance A-286, or alloys containing nickel, chromium and
iron, better known as INCONEL®—manufactured by Inco Alloys International, Inc.
As best illustrated in FIG. 4, the driving anvil
110 is disc-like and
has
an inner diameter which is slightly larger than diameter D
13 of the third
portion
166 of the elongated shank
158.
The honeycomb rivet
100 is utlized to attach honeycomb material
184
to at least a first workpiece
186 and, as described herein, between first
and second workpieces
186,
188. The honeycomb material
184
includes a first honeycomb skin
190 having inner and outer surfaces
192,
194, a second honeycomb skin
196 having inner and outer surfaces
198,
200 and a honeycomb interior
202 which is provided between
the inner surface
192 of the first honeycomb skin
190 and the outer
surface
200 of the second honeycomb skin
196. The first workpiece
186, such as a frame for an aircraft, has inner and outer surfaces
204,
206 and is positioned against the second skin
196 of the honeycomb
material
184 such that the inner surface
198 of the second skin
196
is positioned against the outer surface
206 of the first workpiece
186.
The second workpiece
188, such as an exterior panel for an aircraft, has
inner and outer surfaces
208,
210 and is positioned against the first
skin
190 of the honeycomb material
184 such that the outer surface
194 of the first skin
190 is positioned against the inner surface
208 of the second workpiece
188. The honeycomb material
184
is preferably formed of either aluminum or titanium.
An operation of utilizing the honeycomb rivet
100 to attach the honeycomb
material
184 between the first and second workpieces
186,
188
will now be discussed with relation to FIGS. 4-7.
A hole
212 of uniform diameter is drilled through the first workpiece
186,
the honeycomb material
184 and the second workpiece
188, which uniform
diameter is slightly larger than the diameter D
2 of the sleeve portion
114
of the back side sleeve
102 and the diameter D
6 of the second portion
138 of the sleeve portion
124 of the front side sleeve
104.
Counterbores
214,
216 are also formed in the hole
212 in both
the first and second workpieces
186,
188, respectively. Counterbore
216 is of a size to accommodate the head portion
122 of the front
side sleeve
104 while counterbore
214 is of a size to accommodate
the head portion
112 of the back side sleeve
102. The drilling of
the uniform diameter hole
212 provides for a time saving as it avoids the
need for changing of drill bit sizes to drill different size holes, as done in
the prior art, or for the need for more than one tool.
After the hole
212 and counterbores
214,
216 are formed
within the honeycomb material
184 and the workpieces
186,
188,
the honeycomb rivet
100 is positioned within the hole
212 and the
counterbores
214,
216.
The back side sleeve
102 is positioned within the hole
212 by inserting
the sleeve portion
114 thereof into the hole
212 through the first
workpiece
186, the second skin
196 of the honeycomb material
184
and into the honeycomb interior
202 of the honeycomb material
184,
such that the head portion
112 of the back side sleeve
102 is positioned
within the counterbore
214 and the head portion
112 is flush with
the inner surface
204 of the first workpiece
186. The back side sleeve
102 is easily inserted into the hole
212 as the outer diameter D
2
of the sleeve portion
114 of the back side sleeve
102 is smaller
than the diameter of the hole
212.
The stem member
106, with the internal locking collar
108 positioned
thereon, is positioned within the front side sleeve
104 by inserting the
third portion
166 of the elongated shank
158 of the stem member
106
through the third portion
148 of the aperture
140 of the front side
sleeve
104. As the diameter D
10 of the enlarged stem head
154
is larger than the diameter D
9 of the third portion
148 of the aperture
140, the enlarged stem head
154 does not extend within the aperture
140 of the front side sleeve
104, but rather abuts against the second
end
128 of the front side sleeve
104. Thus, the first portion
160
of the elongated shank
158, having a diameter D
11, is positioned
within the third portion
148 of the aperture
140, having a diameter
D
9. The second portion
162 of the elongated shank
158, having
a diameter D
12, is positioned within both the third portion
148 of
the aperture
140 and the second portion
146 of the aperture
140,
having a diameter D
8. The internal locking collar
108 positioned
on the third portion
166 of the elongated shank
158 is positioned
within the second portion
146 of the aperture
140. The third portion
166 of the elongated shank
158, having a diameter D
13, is
positioned within the second portion
146 of the aperture
140, the
first portion
144 of the aperture
140, and extends beyond the head
portion
122 of the front side sleeve
104.
The combination of the front side sleeve
104 and the stem member
106
is positioned within the hole
212 after the back side sleeve
102
is positioned within the hole
212, as described above, by inserting the
enlarged stem head
154 of the stem member
106 and the sleeve portion
124 of the front side sleeve
104 into the hole
212 through
the second workpiece
188, the first skin
190 of the honeycomb material
184 and into the honeycomb interior
202 of the honeycomb material
184, such that the head portion
122 of the front side sleeve
104
is positioned within the counterbore
216 and the head portion
122
is flush with the outer surface
210 of the second workpiece
188,
and such that the enlarged stem head
154 of the stem member
106 and
a portion of the second portion
138 of the sleeve portion
124 of
the front side sleeve
104 are positioned within the aperture
120
of the sleeve portion
114 of the back side sleeve
102. The configuration
of the front side sleeve
104 allows the front side sleeve
104 to
accommodate the uniform diameter hole
212. The sleeve portion
124
of the front side sleeve
104 is tapered between the first and second portions
132,
138 thereof to allow the second portion
138 thereof to
be inserted into the aperture
120 of the sleeve portion
114 of the
back side sleeve
102. A gap
218 is formed between the sleeve portion
114 of the back side sleeve
102 and the enlarged stem head
154
of the stem member
106. The gap
218 is necessary for the expansion
of the front and back side sleeves
104,
102 due to the installation,
which is easily satisfied in a honeycomb structure.
The driving anvil
110 is placed around the third portion
166 of
the elongated shank
158 to abut against the first end
126 of the
front side sleeve
104.
After the honeycomb rivet
100 is positioned within the hole
212,
the conventional pull type tool
178 is positioned around the third portion
166 of the elongated shank
158 such that an end thereof abuts against
the driving anvil
110, as illustrated in FIG. 4, and applies a firm, steady
pressure to the driving anvil
110 to seat the head portion
122 of
the front side sleeve
104 within the counterbore
216 of the hole
212. The driving anvil
110 eliminates wear and replacement of expendable
pull tool components, considerably extending the life of the pull tool
178.
As illustrated in FIG. 5, the pull type tool
178 applies a downward compressive
force F
1 on the driving anvil
110 in order to hold both the back
and front side sleeves
102,
104 in place, while at the same time
applying an upward tensile force F
2 to the pulling portion
172 of
the elongated shank
158 of the stem member
106. The force F
2
causes the enlarged stem head
154 to upset the second portion
138
of the sleeve portion
124 of the front side sleeve
104, proximate
to the second end
128 of the front side sleeve
104, which in turn
upsets the sleeve portion
114 of the back side sleeve
102, proximate
to the second end
118 of the back side sleeve
102. The upsetting
of the sleeve portions
124,
114 of the front and back side sleeves
104,
102, respectively, causes the front and back side sleeves
104,
102 to lock together and to fasten the joint of the honeycomb rivet
100
within the honeycomb material
184.
As illustrated in FIG. 6, as the pull tool
178 continues to apply the
force
F
2 to the pulling portion
172 of the elongated shank
158 of
the stem member
106, the lock sleeve portion
182 of the internal
locking collar
108 comes into contact with the driving anvil
110,
forcing the lock sleeve portion
182 of the internal locking collar
108
to deform and fill into the first portion
144 of the aperture
140
of the front side sleeve
104. The deformation of the internal locking collar
108 into the first portion
144 of the aperture
140 of the
front side sleeve
104 securely locks the stem member
106 and the
front side sleeve
104 together. The internal locking collar
108 enhances
joint integrity and reliability, and is visible after installation. The internal
locking collar
108 also prevents the stem member
106 from rattling
and, as it is held in place, further helps insure shear load across the honeycomb
rivet
100.
Continued application of the force F
2 by the pull tool
178
causes the elongated shank
158 of the stem member
106 to fracture
at the break notch
179, providing a flush, burr-free installation, as illustrated
in FIG.
7.
Attention is now directed to the second embodiment of the honeycomb rivet
300 as illustrated in FIGS. 8-11. The honeycomb rivet
300 of the
second embodiment includes a back side sleeve
302, a front side sleeve
304,
a stem member
306, an external locking collar
309, and a shifting
washer
311.
The back side sleeve
302, the front side sleeve
304 and the stem
member
306 of the honeycomb rivet
300 are identical to the back side
sleeve
102, the front side sleeve
104 and the stem member
106
of the honeycomb rivet
100 and, therefore, the description of these items
will not be repeated. Similarly, the honeycomb material
384 and workpieces
386,
388 are identical to the honeycomb material
184 and workpieces
186,
188 and, therefore, the description thereof will not be repeated.
As best illustrated in FIG. 8, the external locking collar
309 has an
annular
cylindrical shape and is used for the setting or locking of the honeycomb rivet
300. The external locking collar
309 is positioned around the third
portion
366 of the elongated shank
306 between the break neck
379
and the pulling portion
372. The external locking collar
309 has
an inner diameter which is slightly larger than diameter D
13 of the third
portion
366 of the elongated shank
306, and an outer diameter which
is larger than the inner diameter thereof and is slightly smaller than diameter
D
7 of the first portion
344 of the aperture
340 within the
front side sleeve
304. The external locking collar
309 is preferably
formed of a cold deformable material such as precipitation-hardening stainless
steel, for instance A-286, or alloys containing nickel, chromium and iron, better
known as INCONEL®—manufactured by Inco Alloys International, Inc.
As best illustrated in FIG. 8, the shifting washer
311 has an upper washer
element
420 and a lower washer element
422 which are concentrically
arranged but axially offset from each other as shown in the drawings. A shear section
424 is employed in joining together the upper washer element
420
and the lower washer element
422 as shown in the drawings. As will hereinafter
become more apparent, the upper washer element
420 is of such size as to
freely slidably fit within the internal dimension or configuration of the lower
washer element
422 upon shear or failure of the shear section
424.
An operation of utilizing the honeycomb rivet
300 to attach the honeycomb
material
384 between the first and second workpieces
386,
388
will now be discussed with relation to FIGS. 8-11.
A hole
412 of uniform diameter is drilled through the first workpiece
386,
the honeycomb material
384 and the second workpiece
388, which uniform
diameter is slightly larger than the diameter D
2 of the sleeve portion
314
of the back side sleeve
302 and the diameter D
6 of the second portion
338 of the sleeve portion
324 of the front side sleeve
304.
Counterbores
414,
416 are also formed in the hole
412 in both
the first and second workpieces
386,
388, respectively. Counterbore
416 is of a size to accommodate the head portion
322 of the front
side sleeve
304 while counterbore
414 is of a size to accommodate
the head portion
312 of the back side sleeve
302. The drilling of
the uniform diameter hole
412 provides for a time saving as it avoids the
need for changing of drill bit sizes to drill different size holes, as done in
the prior art, or for the need for more than one tool.
After the hole
414 and counterbores
414,
416 are formed
within the honeycomb material
384 and the workpieces
386,
388,
the honeycomb rivet
300 is positioned within the hole
412 and the
counterbores
414,
416.
The back side sleeve
302 is positioned within the hole
412 by inserting
the sleeve portion
314 thereof into the hole
412 through the first
workpiece
386, the second skin
396 of the honeycomb material
384
and into the honeycomb interior
402 of the honeycomb material
384,
such that the head portion
312 of the back side sleeve
302 is positioned
within the counterbore
414 and the head portion
312 is flush with
the inner surface
304 of the first workpiece
386. The back side sleeve
302 is easily inserted into the hole
412 as the outer diameter D
2
of the sleeve portion
314 of the back side sleeve
302 is smaller
than the diameter of the hole
412.
The stem member
306 is positioned within the front side sleeve
304
by inserting the third portion
366 of the elongated shank
358 of
the stem member
306 through the third portion
348 of the aperture
340 of the front side sleeve
304. As the diameter D
10 of the
enlarged stem head
354 is larger than the diameter D
9 of the third
portion
348 of the aperture
340, the enlarged stem head
354
does not extend within the aperture
340 of the front side sleeve
304,
but rather abuts against the second end
328 of the front side sleeve
304.
Thus, the first portion
360 of the elongated shank
358, having a
diameter D
11, is positioned within the third portion
348 of the aperture
340, having a diameter D
9. The second portion
362 of the elongated
shank
358, having a diameter D
12, is positioned within both the third
portion
348 of the aperture
340 and the second portion
346
of the aperture
340, having a diameter D
8. The third portion
366
of the elongated shank
358, having a diameter D
13, is positioned
within the second portion
346 of the aperture
340, the first portion
344 of the aperture
340, and extends beyond the head portion
322
of the front side sleeve
304.
The combination of the front side sleeve
304 and the stem member
306
is positioned within the hole
412 after the back side sleeve
302
is positioned within the hole
412, as described above, by inserting the
enlarged stem head
354 of the stem member
306 and the sleeve portion
324 of the front side sleeve
304 into the hole
412 through
the second workpiece
388, the first skin
390 of the honeycomb material
384 and into the honeycomb interior
402 of the honeycomb material
384, such that the head portion
322 of the front side sleeve
304
is positioned within the counterbore
416 and the head portion
322
is flush with the outer surface
410 of the second workpiece
388,
and such that the enlarged stem head
354 of the stem member
306 and
a portion of the second portion
338 of the sleeve portion
324 of
the front side sleeve
304 are positioned within the aperture
320
of the sleeve portion
314 of the back side sleeve
302. The configuration
of the front side sleeve
304 allows the front side sleeve
304 to
accommodate the uniform diameter hole
412. The sleeve portion
324
of the front side sleeve
304 is tapered between the first and second portions
332,
338 thereof to allow the second portion
338 thereof to
be inserted into the aperture
320 of the sleeve portion
314 of the
back side sleeve
302. A gap
418 is formed between the sleeve portion
314 of the back side sleeve
302 and the enlarged stem head
354
of the stem member
306. The gap
418 is necessary for the expansion
of the front and back side sleeves
304,
302 due to the installation,
which is easily satisfied in a honeycomb structure.
The external locking collar
308 is placed around the third portion
366
of the elongated shank
358 such that the external locking collar
308
is positioned proximate to, or partially within, the first portion
344 of
the aperture
340 of the front side sleeve
304.
The shifting washer
310 is positioned around the third portion
366
of the elongated shank
358 such that a bottom surface
426 of the
lower washer element
422 abuts against the first end
326 of the front
side sleeve
304, and a bottom surface
428 of the upper washer element
420 abuts against the external locking collar
308.
After the honeycomb rivet
300 is positioned with the hole
412,
the conventional pull type tool
378 is positioned around the third portion
366 of the elongated shank
358 such that an end thereof abuts against
a top surface
430 of the upper washer element
420 of the shifting
washer
311, as illustrated in FIG. 8, and applies a firm, steady pressure
to the shifting washer
311 to seat the head portion
322 of the front
side sleeve
304 within the counterbore
416 of the hole
412.
The shifting washer
311 eliminates wear and replacement of expendable pull
tool components, considerably extending the life of the pull tool
378, as
well as performing another function as will be described herein.
As illustrated in FIG. 9, the pull type tool
378 applies a downward compressive
force F
1 on the shifting washer
311 in order to hold both the back
and front side sleeves
302,
304 in place, while at the same time
applying an upward tensile force F
2 to the pulling portion
372 of
the elongated shank
358 of the stem member
306. The force F
2
causes the enlarged stem head
354 to upset the second portion
338
of the sleeve portion
324 of the front side sleeve
304, proximate
to the second end
328 of the front side sleeve
304, which in turn
upsets the sleeve portion
314 of the back side sleeve
302, proximate
to the second end
318 of the back side sleeve
302. The upsetting
of the sleeve portions
324,
314 of the front and back side sleeves
304,
302, respectively, causes the front and back side sleeves
304,
302 to lock together and to fasten the joint of the honeycomb rivet
300
within the honeycomb material
384.
As illustrated in FIG. 10, as the pull tool
378 continues to apply the
force F
1 to the upper washer element
420 of the shifting washer
311,
the f
