U.S. patent application number 17/536912 was filed with the patent office on 2022-07-21 for method and a device for the manufacturing of washers for locking and washer for locking.
The applicant listed for this patent is Nord-Lock AB. Invention is credited to Mattias Andersson.
Application Number | 20220226879 17/536912 |
Document ID | / |
Family ID | 1000006244728 |
Filed Date | 2022-07-21 |
United States Patent
Application |
20220226879 |
Kind Code |
A1 |
Andersson; Mattias |
July 21, 2022 |
Method and a Device for the Manufacturing of Washers for Locking
and Washer for Locking
Abstract
A method for the manufacturing of circular washers for locking
from blanks, the washer having a central hole, a first side
comprising a pattern of radially extending teeth and a second side
comprising a pattern of radially extending cams. The method is
especially characterized in the steps of producing a washer blank
having an annular shape; introducing the washer blank into a die
assembly for forming a closed shaping space by a lower die portion,
an opposing upper die portion, a central die portion and a support
piece, the central die portion extending through a washer blank
central hole; forming the blank to a washer by mutual movement of
said lower and upper die portions; opening the closed shaping space
to extract the formed washer. The invention also relates to a
device and a washer.
Inventors: |
Andersson; Mattias;
(Ostersund, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nord-Lock AB |
Mattmar |
|
SE |
|
|
Family ID: |
1000006244728 |
Appl. No.: |
17/536912 |
Filed: |
November 29, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15468597 |
Mar 24, 2017 |
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17536912 |
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12680000 |
Mar 25, 2010 |
9636738 |
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PCT/SE2008/051081 |
Sep 26, 2008 |
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15468597 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16B 39/24 20130101;
B21D 53/22 20130101; F16B 43/00 20130101 |
International
Class: |
B21D 53/22 20060101
B21D053/22; F16B 39/24 20060101 F16B039/24; F16B 43/00 20060101
F16B043/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2007 |
SE |
0702188-4 |
Claims
1. A locking washer produced from a blank, the washer having a
central hole and on one side comprising a pattern of radially
extending teeth and on the other side comprising a pattern of
radially extending cams, wherein the pattern of radially extending
teeth and the pattern of radially extending cams extend from the
inner periphery to the outer periphery of the washer.
2. A locking washer according claim 1, wherein the washer is formed
with a bevelled configuration at the inner periphery adaptable to a
radius under the head of a bolt to be locked by a washer
configuration.
3. A locking washer according to claim 2, wherein the bevelled
configuration is formed on the tooth pattern side of the
washer.
4. A locking washer according to claim 1, wherein the locking
washer is a metal locking washer.
5. A locking washer according to claim 4, wherein the metal is a
steel.
6. A locking washer according to claim 5, wherein the steel is a
low-alloy steel.
7. A locking washer according to claim 6, wherein the low-alloy
steel is hardenable to a hardness of about or exceeding 465 HV.
8. A locking washer according to claim 1, wherein the washer is
configured with an outer diameter for the washer to fit in a
standard dimension counter bored hole having a flat bottom.
9. A locking washer according to claim 1, wherein the thickness of
the washer being less than 1 mm.
10. A locking washer produced from a blank according to claim 1,
wherein the blank is formed to an annular washer in a closed
shaping space formed by a die assembly comprising a lower die
portion, an upper die portion, a central die portion and a support
piece.
11. A locking washer according to claim 1, wherein said blank is
cut from a rolled strip.
12. A locking washer according to claim 1, wherein said blank is
formed from a wire having a circular cross-section.
13. A locking washer according to claim 1, wherein said blank is
formed from a wire having a square cross-section.
14. A device for the manufacturing of circular washers for locking
from blanks, each washer having a central hole for a bolt element,
a first side comprising a pattern of radially extending teeth and
an opposite second side comprising a pattern of radially extending
cams; wherein said washer blank to be formed has an annular shape;
a die assembly for forming said blank being provided, the die
assembly comprising a lower die portion, an opposing upper die
portion, a central die portion and a support piece; the lower and
upper die portions being mutually movable and arranged to form a
closed shaping space together with the central die portion and the
support piece; the die assembly being arranged to receive a washer
blank and to form a washer in said closed shaping space, the
central die portion being arranged to extend through the washer
central hole during said forming.
15. A device according to claim 14, wherein the blank to be formed
in the die assembly is cut from a thin strip.
16. A device according to claim 14, wherein the blank to be formed
in the die assembly is formed from a wire having a circular
cross-section.
17. A device according to claim 14, wherein the blank to be formed
in the die assembly is formed from a wire having a square
cross-section.
18. A device according to claim 14, wherein the die assembly is
arranged for cutting the blank in the die assembly prior to forming
the blank.
19. A device according to claim 14, wherein means are provided for
forcing the lower die portion towards the upper die portion for
forming the closed shaping space by the three die portions and the
support piece by forcing the upper die portion against an end stop
with the washer blank material applied in said space, the lower die
portion being arranged to be further forced towards the upper die
portion for forming the washer blank to a washer.
20. A device according to claim 14, wherein spring means are
provided to provide a spring force, against which the upper die
portion is displaced when forced towards the end stop.
21.-27. (canceled)
Description
1. BACKGROUND
1.1 the Present Invention Relates to a Method for the Manufacturing
of Washers for Locking
[0001] The present invention also relates to a device for the
manufacturing of washers for locking.
[0002] Further, the invention relates to a washer for locking.
1.2 Prior Art
[0003] Washers as described above are previously known and provided
for eg bolts or the corresponding fastening elements for locking
purposes. In a locking system of this kind two washers are arranged
in a pair, the cam pattern sides facing and engaging each other,
the main cam surface inclination being larger than the pitch of the
threads, which causes a positive and efficient locking of the
fastening element.
[0004] According to what is previously known the washers are
manufactured from a strip blank, which is fed to pass several
stations, in which forming and/or punching is performed between
upper and lower tools, the pattern of teeth being formed on and
substantially covering the upper surface and the pattern of cams
being formed on and substantially covering the lower surface of the
washer.
[0005] This known technique is associated with several
disadvantages and problems. Thus, there is a possibility that
undesired displacements occur between the stations during feeding
in the die arrangement, such displacements causing defect washers.
Further, the total amount of blank material is quite high.
Furthermore, there are restrictions related to the cam and teeth
cover on each side of the washers, which decreases the possible
load bearing surfaces. Also, the outer periphery is punched out and
then receives a sharp edge, which causes problems in the further
processing of the washer.
[0006] As described in Applicant's Swedish Patent Application No.
0501224-0 the outer periphery of the tooth pattern is deformed
during the punching out of the washer. Therefore an edge zone free
from pattern is formed, against which the punch rests during
punching. This restricts the load transferring surface of the
washer.
[0007] The object of present invention is to provide a solution to
these problems associated with previously known technique.
SUMMARY OF THE INVENTION
[0008] The object of the present invention is obtained by a method,
a device and a locking washer having the features specified in the
claims.
[0009] Further advantages are obtained by what is specified in the
respective dependent claims.
SHORT DESCRIPTION OF THE DRAWINGS
[0010] A better understanding of the present invention will be had
in view of the following description related to examples and
preferred embodiments, when read in conjunction with the drawings,
in which
[0011] FIGS. 1A-1E) schematically show axial cross-sectional views
of a first embodiment of a die assembly according to the present
invention in different process steps for forming a washer according
to the present invention,
[0012] FIG. 2 schematically shows a first embodiment of a washer
blank cut from a rolled strip,
[0013] FIG. 3 schematically shows a second embodiments of a washer
blank formed from a wire having a circular cross-section,
[0014] FIG. 4 schematically shows a third embodiment of a washer
blank formed from a wire having a square cross-section,
[0015] FIGS. 5A-5F schematically shows a washer produced according
to the invention seen in perspective views, a front and a side view
and a cross-sectional view.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0016] In FIG. 1A a die assembly for the manufacturing of locking
washers is designated by 1. In FIGS. 5A to 5F, an example of a
washer 2 to be produced according to the invention is shown. These
kind of locking washer comprises a central hole 3 for a bolt
element to be locked by a washer arrangement and on one side 4 a
pattern of radially extending teeth 5 and on the other, the
opposite, side 6 a pattern of radially extending cams 7. The washer
has an annular configuration and the respective patterns extend
from the inner periphery 8 to the outer periphery 9. According to
preferred embodiments the washer comprises a bevelled portion 10 at
the inner periphery, preferably on the side 4 having the pattern of
teeth, the bevelled portion being intended to adapt to a radius
portion under the head of a bolt element.
[0017] The die assembly preferably has an axi-symmetric
configuration coinciding with the axial direction 11 of a washer to
be formed.
[0018] The die assembly comprises a lower die portion 12, an upper
portion 13 and a central portion 14. According to the embodiment
shown the central die portion is fixed and the lower die portion
and the upper die portion are mutually movable and arranged to form
a closed shaping space 15 together with the central die portion and
a support piece 1' for providing a circumferentially running outer
wall of said space, a washer blank 2', being intended to be formed
to a washer in said closed shaping space 15. In FIG. 1A the die
assembly is open to receive a washer blank 2'.
[0019] The lower die portion having received said blank, is movable
towards the upper die portion, means, represented by an arrow F,
being provided for forcing the lower die portion towards the upper
die portion for forming said closed shaping space by the die
portions by forcing the upper die portion against an end stop 16
with the washer blank material applied in said space 15, the lower
die portion being arranged to be further forced towards the upper
die portion for forming the washer blank to a washer as shown in
FIG. 1C and FIG. 1D.
[0020] According to a preferred embodiment spring means 17 are
provided to provide a spring force F', against which the upper die
portion is displaced when forced towards the end stop, said spring
force being provided for pushing out the formed washer when
unloading the force F exerted by the lower die portion by
retracting the lower die portion.
[0021] The spring force is acting on the upper die portion by eg
rods 18 acting on an upper portion 19 of the upper die portion, as
schematically shown in FIG. 1D. Of course another guiding
arrangement that the rods 18 may be imagined and for exerting a
spring force F'.
[0022] According to preferred embodiments the die assembly is
configured to form the tooth pattern and the cam pattern to extend
from the inner periphery 8 of the washer to the outer periphery 9
of the washer. Preferably, the lower die portion 12 is designed to
form the pattern of cams and the upper die portion 13 is designed
to form the pattern of teeth.
[0023] According to preferred embodiments the die assembly,
preferably by a bevelled end portion 20 of the central die portion
as shown in FIG. 1E, is designed to form the washer with a bevelled
configuration at the inner periphery to adapt to a radius under the
head of a bolt intended to be locked by a washer arrangement, as
described earlier, the bevelled configuration preferably being
formed on the tooth pattern side 4 of the washer.
[0024] According to one embodiment the blank 2' to be formed is cut
from a metal strip 2''. Such a blank is schematically shown in FIG.
1B.
[0025] According to another embodiment the blank 2' to be formed in
the die assembly is formed from a wire 21 having a circular
cross-section, as shown in FIG. 3.
[0026] According to a further embodiment the blank 2' to be formed
in the die assembly is formed from a wire 21' having a square
cross-section, as shown in FIG. 4.
[0027] According to a still further embodiment an annular blank 2',
as schematically shown in FIG. 1B-C, the die assembly is configured
for cutting the blank from a strip 2'' in the die assembly prior to
forming the blank. In such a case the lower die portion is provided
with a circumferentially running edge portion 22 and the die
assembly is provided with a support piece 1', which, apart from
providing the circumferentially running wall of the closed shaping
space, provides a cutting edge 24 for the blank cutting operation,
the lower die portion working as a punch in this operation, the
operation being schematically shown in FIG. 1C.
[0028] Embodiments may also be imagined according to which a blank
in the form of a circular disc, ie without a central hole, is
produced, the hole being punched out in the die assembly during
forming of the washer, preferably by a central die portion.
[0029] In such a case the blank may be punched from a strip or
being out, preferably by high velocity cutting, from a wire or a
bar or a rod, high velocity cutting being performed with a very
small play between the cutting dies and, thus produces a blank with
a very accurate disc shape.
[0030] The method and function of the device according to the
invention as well as the washer according to the invention should
to a considerable and sufficient extent have been made clear from
the description given above.
[0031] For the forming of a washer blank introduced in the die
assembly a closed shaping space is formed by a lower die, an upper
die, a central die and a support piece. Once the blank is properly
introduced the total forming operation for the finished washer is
performed in said closed space, which offers a number of
advantages, including a proper forming of the two patterns with an
extension from the inner periphery to the outer periphery.
[0032] In this way one blank or several blanks at the same time
is/are formed in one single operation in a closed shaping space, In
this way die setting is considerably simplified compared to a
process in which a final product is formed in consecutive forming
operations linked together by a blank strip, wherein the forming
steps depend on each other and require an extremely accurate mutual
setting, which requires continuous monitoring and maintenance.
[0033] According to preferred embodiments annular washer blanks are
punched out/cut out from strips or sheets before being introduced
into the die assembly 1. In this way the blanks may be punched out
in a closely packed pattern, which saves the amount of blank raw
material. These blanks may be fed to the die assembly in any
convenient way prior to forming.
[0034] Other advantages are eg [0035] very accurate finished
product dimensions; [0036] reduced material consumption since less
space between the blanks when cut from a strip is necessary; [0037]
less raw material storage since the number of band widths may be
reduced; [0038] increased process security due to only a small
number of settings are necessary; [0039] more efficient use of
building area due to smaller press equipment; [0040] lower
electrical power level necessary; [0041] smaller number of finished
product defects offers higher productivity in glueing operations;
[0042] thinner washers having a limited outer diameter may be
produced due to accurate blank production.
[0043] Above examples and preferred embodiments have be given.
[0044] Of course, further embodiments as well as minor changes and
additions may be imagined without departing from the basic
inventive idea.
[0045] Thus, the washers are preferably made of steel, in
particular low-alloy steel hardenable to a hardness of about or
exceeding 465 HV.
[0046] According to preferred embodiments the washers are designed
with an outer diameter for the washer to fit in a standard
dimension counter bored hole having a flat bottom, the thickness of
the washers being down to less than 1 mm, and according to
preferred embodiments the die assembly is designed for forming such
washers.
[0047] Thus, the invention should not be considered limited to the
embodiments shown but can be varied within the scope of the
attached claims.
* * * * *