U.S. patent number 3,643,304 [Application Number 04/824,827] was granted by the patent office on 1972-02-22 for method of simultaneously drawing a number of wire members.
This patent grant is currently assigned to Nippon Seisen Co., Ltd.. Invention is credited to Osami Hirai, Kaoru Kokubu.
United States Patent |
3,643,304 |
Kokubu , et al. |
February 22, 1972 |
METHOD OF SIMULTANEOUSLY DRAWING A NUMBER OF WIRE MEMBERS
Abstract
A number of wires are gathered together and bound with an
armoring material in the shape of a band. The wires in this
condition are drawn by means of a wire-drawing apparatus having
dies and a capstan. A plurality of bundles of such wires are
gathered together and bound in the same way as in the foregoing to
form a composite bundle body, which is further drawn, and these
processes are repeated until at last filaments of a specified
diameter are obtained in quantities.
Inventors: |
Kokubu; Kaoru (Osaka,
JA), Hirai; Osami (Osaka, JA) |
Assignee: |
Nippon Seisen Co., Ltd. (Osaka,
JA)
|
Family
ID: |
25242426 |
Appl.
No.: |
04/824,827 |
Filed: |
May 15, 1969 |
Current U.S.
Class: |
29/423;
29/728 |
Current CPC
Class: |
B21C
1/00 (20130101); B21C 37/047 (20130101); Y10T
29/4981 (20150115); Y10T 29/53126 (20150115) |
Current International
Class: |
B21C
37/00 (20060101); B21C 1/00 (20060101); B21C
37/04 (20060101); B23p 017/00 () |
Field of
Search: |
;29/423,424,202.5,474.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Campbell; John F.
Assistant Examiner: Di Palma; Victor A.
Claims
We claim:
1. A method for manufacturing filament, comprising the step of:
gathering and bundling a plurality of wire members in parallel
relationship to one another while feeding said wire members in a
predetermined direction;
feeding a band-shaped armoring of medium carbon steel out of a reel
in parallel with said bundled wire members, said band-shaped
armoring being formed into the shape of an upwardly directed
conduit;
storing the gathered plurality of wire members within said armoring
formed into the shape of a conduit such that each wire member is
parallel to the longitudinal axis of said conduit;
enveloping said wire members in said conduit by closing said
armoring such that said wire members are compressed by forces
exerted by said armoring, thus tightly binding said wire members
together forming an enveloped bundle of said wire members;
drawing said enveloped bundle by means of dies; and
removing said armoring from said wire members.
2. A method substantially as set forth in claim 1, including the
step of:
providing cold machinability to said bundle by means of dies.
3. A method substantially as set forth in claim 1, including the
steps of:
providing cold machinability to said bundle by applying at least
one thermotreatment to said bundle in an oxidation atmosphere;
and
producing at least one oxide film on the surface of said wire
members.
4. A method substantially as set forth in claim 1, including the
step of:
forming said armoring into the shape of a conduit by means of a
roll.
5. A method according to claim 1, including the step of:
extracting said enveloped bundle from said dies by means of a
capstan.
6. A method for manufacturing stainless filament, comprising the
steps of:
bundling a plurality of stainless wire members in a parallel
arrangement while feeding said stainless wire members in a
predetermined direction;
feeding a band-shaped armoring of medium carbon steel out of a reel
in parallel with said bundled stainless wire members which are
being fed in said predetermined direction, said band-shaped
armoring being formed into the shape of an upwardly directed
conduit;
feeding the bundle of substantially parallel arranged stainless
wire members into said conduit-shaped armoring;
enveloping said wire members in said conduit by closing said
armoring such that said wire members are compressed by forces
exerted by said armoring, thus tightly binding said wire members
together forming an enveloped bundle of said wire members;
drawing said enveloped bundle of said wire members by means of
dies;
preparing a plurality of such enveloped bundles of wire members
through the same procedure in accordance with the preceding
steps;
sheathing the plurality of bundles of wire members with a
band-shaped armoring of medium carbon steel;
drawing said sheathed bundles of wire members;
removing said armoring from said wire members.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method and apparatus for drawing a
plurality of filaments bound with an armoring material in the shape
of a band, and thereby providing a plurality of leaner filaments,
both efficiently and economically.
2. Description of the Prior Art
Some of the methods of obtaining from filaments of a given diameter
those of a smaller diameter are mentioned herein. One is termed
"single-head wire drawing," wherein filaments of a given diameter
are passed through a single die one by one to form filaments of a
smaller diameter. Another method is called "continuous wire
drawing," wherein an apparatus comprising a plurality of dies and
capstans corresponding in number to such dies is utilized. Another
method involves inserting a filament of a given diameter into a
tubular body having a caliber conforming to the diameter of the
filament to form an integrated double structure, which is then
drawn; and a plurality of said double structures are inserted into
a tubular body of a greater caliber to be drawn as in the
foregoing, and thereafter the processes of insertion into said
tubular body and drawing are repeated.
In the first two methods, drawing is effected after inserting one
wire into one die. Consequently, not only a bulky device is
required for mass production, but also such methods are unsuitable
for obtaining the so-called "filaments" having minute diameters.
There is a further disadvantage, characteristic of wire drawing
machining in general, that the machining speeds are extremely
low.
It is only natural that the last of the above-mentioned three
methods is considered the most suited for filament molding and, in
fact, is adopted for practical use to prove its efficiency to a
certain extent. This method has disadvantages too. First, technical
difficulties are inevitable in a process of inserting a wire
material of a great length into an elongated tube having a caliber
conforming to the peripheral shape of the wire material for
integration. Secondly, as in the first two methods, a process of
drawing a wire (of a double structure in this case) through one die
is of utmost importance, entailing great technical difficulties yet
unsolved in the case of mass production. Thirdly, in this method,
the filament obtained is of complex, multiple layers, with the
armoring tubular bodies succeedingly enveloping an inner one from
the outside according to the number of times of wire drawing. The
volume of the tubular bodies at the armoring removing step in the
last process is too great as compared with the total volume of the
filaments, with resultant waste in time and labor required for
armor removal, and high cost needed for the armoring tubular
bodies. This method is, therefore, by no means a money-saving
one.
SUMMARY OF THE INVENTION
The present invention solves the problems of the conventional
techniques. The primary object of the present invention is to make
drawing molding of a number of filaments simultaneously, and more
specifically to provide quantities of stainless steel filaments
through an uncomplicated process and at low cost. Substantial
uniformity in composition has to be maintained in the filament
material and the armoring material in the shape of a band used for
the main means of the invention, in order to prevent wire breakage
due to differences in inner stress in a drawing process of steel
filaments. The material wire members bound within an armoring
material in the shape of a band has to be prevented from burning
due to the frictional heat generated when these members pass
through the dies in a drawing process of steel filaments.
The present invention provides a method of simultaneously drawing a
number of wire members, including the step of tightly enveloping a
plurality of wire members gathered substantially in parallel
relative to one another with an armoring in the shape of a band to
thereby form a bundle of wire members. Then, cold machinability is
provided to such bundle. Thereafter, the bundle is drawn by means
of dies, and then the armoring is removed from the wire
members.
The present invention also provides an apparatus for simultaneously
drawing a number of wire members. The apparatus includes a roll for
molding a bandlike armoring into the shape of a conduit. The
apparatus also includes a grooved roll for converging a plurality
of wire members to be substantially parallel relative to one
another. There is also provided a roll for closing both sides of
the armoring in the shape of a band to envelop the wire members.
The apparatus also includes dies and a capstan.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a molding wire-drawing apparatus for
making the first wire drawing of a bundle of members tightly
enveloped with an armoring material in the shape of a band.
FIG. 2 is a plan view of the apparatus shown in FIG. 1.
FIG. 3 is a plan view showing the condition in the vicinity of
rolls in the preceding process of making a bundle of wire members
by tightly enveloping them with an armoring material in the shape
of a band.
FIG. 4 is a cross-sectional view of a bundle of wire members.
FIG. 5 is an enlarged cross-sectional view of a drawn bundle.
FIG. 6 is a cross-sectional view of a drawn composite bundle.
FIG. 7 is a graph showing the relation between temperature and time
in the thermal treatment.
DETAILED DESCRIPTION
The invention may be carried out primarily by the apparatus
illustrated in FIGS. 1 and 2. This invention is characterized in
that a bundle of a plurality of wire members, made by tightly
enveloping them with an armoring material in the shape of a band,
is drawn. The apparatus shown in FIGS. 1 and 2, therefore, is
provided with mechanisms for making a bundle of the wire members
with such armoring in the shape of a band, and for drawing the
bundle. The processes of making a bundle of wire members with an
armoring in the shape of a band, and of drawing the bundle of the
wire members thus formed will be explained in accordance with the
attached drawings.
In FIG. 1 the material wire members 1 are previously made
cold-machinable, and are respectively wound around reels (not
shown) to be supplied by being drawn from such reels. The wire
members 1 extracted from the reels are converged substantially in
parallel relative to one another through groove 3 of converging
roll 2.
Reel 5 (FIG. 1) is provided right below the extremity of the device
4 through which the wire members 1 are extracted. A metal armoring
6 in the shape of a band previously provided with cold
machinability is wound around said reel 5. The armoring is
introduced into the device 4 while being held by a pair of
insertion-type guide rolls 7 with flat contact surfaces, and is
passed through molding roll 9 comprising paired wheel shaped so
that is periphery is protruded outwardly and curved and a wheel
having a curved groove 8 so as to pivotably support said first
wheel; Then the armoring, curved so that both left and right edges
are lifted in the longitudinal direction, is led to bending roll 10
which is similar to, but smaller than, the molding roll 9. The
armoring 6 is further curved by the bending roll 10 into the shape
of a conduit, supplied below the converging roll 2, and passes the
converging roll 2 while receiving the wire members 1 from
above.
The armoring 6 in the shape of a band, thus formed and containing
the focused wire members in its curved interior, is supplied to
model squeezing roll 12, composed of two wheels having curved
groove 11 in their peripheries, where the bundle as shown in FIG. 4
is formed. This bundle is finished to a semiperfect bundle by a
longitudinal finishing roll 13 provided next to the squeezing roll
12 and having the same structure as the squeezing roll 12. The
bundle thus finished is wound around capstan 15 through dies 14
provided next to the finishing roll 13, to be subjected to the
first drawing process. The winding in this instance has to be made
with sufficient care so that the both sides of the armoring 6
holding the wire members 1 within may not be opened. It is
therefore required that the diameter of the capstan 15 be of the
maximum possible length. The first drawing process is thus applied
to the bundle, and cold machinability has to be previously provided
to the armoring 6 and the wire members 1, not only for the first
drawing process but for the succeeding drawing processes, too. The
materials for the armoring 6 and the wire members 1 have to be
selected carefully so that they will not be broken during the
drawing operation. Research concerning a possible cause for such
breaking confirms that the work-hardening rate of a metal is
related to its thermal treatment characteristic. From this the
applicants proceeded to make a variety of experiments which
resulted in a conclusion that the materials for the armoring 6 in
the shape of a band and the wire members 1 have to be selected and
their inner stresses adjusted so that their work hardening rates
and thermal treatment characteristics are substantially
coincidental. It has been further concluded that medium carbon
steel is the most suitable for the armoring 6 when a wire-drawing
process, which is the ultimate aim of the present invention, is
applied to stainless steel. The breaking problem is related to the
degree of tightness with which the armoring 6 and the wire members
1 are fit together. Therefore, in a process in which the wire
members 1 are enveloped with the armoring 6, the plurality of wire
members 1 having the same diameter have to be gathered so as to be
virtually in parallel with one another through the converging roll
2 as shown in FIGS. 1 and 2, to form a tight bundle in which the
wire members are contacting one another in as much area as possible
as illustrated in FIG. 4.
Band-shaped armoring material of medium carbon steel is employed
for the drawing process of stainless steel, as mentioned above. The
wire members are adoptable in various cross-sectional shapes, such
as circular, oval, plate shaped, etc. When wire members in a
variety of such shapes are utilized to form the composite bundle,
as shown in FIG. 6, by being enveloped with armoring, the grooves
of the molding roll 9, bending roll 10, and squeezing roll 12 as
well as the hole in the dies 14 have to be selectively prepared.
This has a bearing on the degree of correctness with which the
armoring 6 and wire members 1 are fit together, so that sufficient
care on this score is required in actual operation.
A considerable degree of deformation is applied to the armoring 6
and wire members 1, according to the present invention as mentioned
above, so that cold machinability has to be provided to the
armoring 6 and wire members 1 in order to make them accept said
deformation. Such cold machinability may be provided through
thermal treatment. Thermal treatment for such purpose, as in an
embodiment of this invention described below, is made in accordance
with the graph in FIG. 7 when medium carbon steel S3OC-S5OC is
employed for the armoring 6 and stainless steel SUS27 and other SUS
material for the wire members 1. In other words, a patenting
process is applied to the armoring 6 to form a sorbite system. In
this instance an oxide film can be produced on the surface of the
armoring 6 by performing a cooling process in the air. Such oxide
film can serve as a lubricant when the armoring 6 is drawn by means
of ordinary dies. That is, the cooling process is made in the air
after thermal treatment, so that the inner system of the armoring 6
is turned into a sorbite system to achieve cold machinability, and
simultaneously an oxide film is provided on its surface to make it
lubricous. But a too rapid cooling after thermal treatment often
results in failure of providing a perfect sorbite system to the
armoring 6, so that a lead patenting process is desirable. That is
to say that quenching should be made at more than AC.sub.3 in an
unoxidation atmosphere, and isothermal transformation with lead
bath. A lead film attached on the surface of the armoring in this
instance serves as a lubricant in the wire-drawing operation by
means of the dies. Thus, in lead patenting, cold machinability is
provided to the armoring 6, which is made a nearly perfect sorbite
system, and lubricity can also be acquired by virtue of lead
coating. For effective realization of the present invention,
however, care is needed so that the wire members 1 will not be
burnt due to the heat generated during the drawing process.
Accordingly, the thermal treatment has to be applied in a duly
controlled oxidation atmosphere, such as a feeble oxidation
atmosphere. Owing to the thermal treatment (including a succeeding
cooling process) in said controlled oxidation atmosphere (a feeble
oxidation atmosphere), oxide films can be produced on the surfaces
of the wire members 1 too. The wire members 1 are thus prevented
from being burned due to heat as they lose their activity on their
surfaces. In short, such thermal treatment has to be applied with
sufficient care so that no ill effects will be given to the wire
members 1, and that the cooling will not be too rapid.
The bundle, having thus undergone such a cold machining treatment,
is then subjected to a drawing process by means of dies. Ordinary
dies are suitable in the present invention, but roll dies may also
be employed.
The drawing process is made by means of a wire-drawing machine
comprising a capstan and dies having sufficient capability of
drawing a bundle of wires. In the drawing process, the wire-drawing
velocity has to be controlled according to the selective
combination of the armoring 6 and the wire members 1. The cross
section of the extracted bundle body is such that the wire members
1 are compressed from outside to be deformed and tightly bound
together with their diameters contracting, and that the superposed
extremities of the armoring 6 are forced into an integral whole;
and the bundle as a whole makes up a filament of a smaller diameter
than before. In the drawing process for the purpose of filament
molding, for example, the blank is not drawn at a stretch until a
predetermined filament diameter is obtained; but the drawing
process is reiterated with intervening patenting treatment,
annealing, and lubrication treatment applied to the armoring 6,
while sufficient care is being taken so as to give no ill effects
to the wire members 1, until at last the predetermined filament
diameter is obtained.
After the wire members 1 have been formed into a filament of a
given diameter, the armoring 6 and the wire members 1 are
separated. A mechanical method may be employed for such separation,
but a chemical method is more desirable in case of a filament
having a minute diameter.
The present invention is materialized in a device illustrated in
FIGS. 1 and 2, and explanation on said device is given in the
following:
Dies and rolls for making duide machining of the armoring 6 and the
wire members 1, etc., are mounted on bed 16 as shown in FIG. 1.
Roll 7 of the aforementioned rolls is a guide roll, supported by
the case 17 as the molding roll 9, with one of the wheels provided
so as to be adjustable in the vertical direction by handle 18. The
molding roll 9 and bending roll 10 are provided in the same way.
The converging roll 2 is supported by arm 19, and the squeezing
roll 12 is adjustably laid on roll base 20.
The finishing roll 13 is supported by case 21, one of the wheels
thereof being adjustable by the handle 18.
The dies 14 are stored in dies box 22, which is mounted on the bed
16 by means of fixing lever 23.
In installing such rolls and dies, extra card should be taken so
that the grooves of the rolls and the hole of the dies are provided
on a semirectilinear line. Circular capstan 15 of a large diameter
is provided in such a way that the circumference thereof contacts
the extension of a line connecting the grooves and hole of the
rolls and dies thus arranged.
Motor 25 provides a means for driving said rolls and capstan. Drive
shaft 26 is pivotally supported by bearings 27 and has a pulley 28
which is connected to pulley 29 of the motor 25 through belt 30.
Drive gear 31 is secured to the drive shaft 26. The drive gear 31
is engaged with clutch gear 34 which is supported by clutch shaft
32 and connected with spring clutch 33. Bearings 35 in FIG. 2
pivotally support the clutch shaft 32. The clutch shaft 32 is
provided with an intermediate gear 36 which is detachable with
respect to the clutch gear 34 through the clutch shaft 32. The
intermediate gear 36 is engaged with driven gear 39 on driven shaft
38 which has capstan 15 at one end and the sprocket 37 at the
middle portion thereof. Bearings 40 in FIG. 2 pivotally support the
driven shaft 38. The capstan 15 has its body proper formed in the
shape of a wheel, and has an auxiliary bar 24 in the shape of a
letter L fixed to its inner surface by means of screw handle 41
said bar protruding at the outer edge of the capstan 15.
The sprocket 37 is connected by a chain 43 to sprocket 42 which is
pivotally supported and projecting athwart from right below the
finishing roll 13. The sprocket 42 is provided on the same shaft as
the sprockets 44 and 45. The sprocket 45 is connected by chain 47
to the sprocket 46 secured on the same shaft as the finishing roll
13. The sprocket 44 is connected by chain 49 to the sprocket 48
which is provided integrally with and is fixed on the same shaft as
the molding roll 9.
There is also provided a clutch operating device 50, a clutch
operating lever 51, and a connecting gear device 52.
With regard to the operation of the device in FIGS. 1 and 2, the
rotation of the motor 25 is transferred to the pulley 28 through
the belt 30. The drive shaft 26 is rotated by the rotation of the
pulley 28, and consequently the drive gear 31 which is fixed to the
drive shaft 26 is then rotated. Since the drive gear 31 is engaged
with the clutch gear 34, the clutch gear 34 is then rotated. If, in
this instance, the clutch gear 34 and intermediate gear 36 are
geared and integrated by the operation of the spring clutch 33 due
to the clutch-operating device 50, then torque is transferred to
the driven gear 39 engaged with the intermediate gear 36. In this
manner, the driven shaft 38 and then the capstan 15 and sprocket 37
are rotated, the rotation of the sprocket 37 being transferred to
the sprocket 42 through the chain 43 and then to the sprockets 44
and 45 provided on the same shaft as the sprocket 42. The rotation
of the sprocket 45 is transferred to the sprocket 46 of the
finishing roll 13 through the chain 47 to drive the finishing roll
13. The rotation of the sprocket 44 is transferred to the sprocket
48 of the molding roll 9 through the chain 49 to drive the molding
roll 9; and the guide roll 7 is driven by the connecting gear
device.
Thus, the wire members 1 introduced by the guide roll 7 pass
through the rolls and dies to be wound compulsorily by the capstan
15.
To attain some of the advantages of the present invention, the wire
drawing by the dies is applied to a bundle of wire members made by
tightly enveloping them with an armoring in the shape of a band, so
that a number of drawn filaments are obtainable in one drawing
process. Especially, by the use of armorings in the shape of a
band, the invention allows efficient mass production, unlike the
conventional methods of applying wire members to dies one by one
and of inserting a wire member into a tubular body and enveloping a
plurality of the tubular bodies with that of a larger diameter for
drawings. The technical difficulties in inserting a wire member
into a tubular body in the second conventional method have been
eliminated too. One of the characteristics of the present invention
is that drawing is made to long wire members continuously enveloped
with an armoring in the shape of a band, so that longer filaments
are obtainable than by conventional methods. Another characteristic
of the present invention is that diameters convenient for handling
in actual machining can be maintained due to the above-stated
reason and that the wire members can be substantially carried by
the armoring even when the filament has become thin to a
considerable degree. Consequently, a filament of an extremely
minute diameter can be molded.
Also, according to the present invention, a number of wire members
are enveloped with a single-layer armoring, so that no unduly long
time is required for removing the armoring from the wire members as
compared with conventional methods, and therefore efficient
machining operation is ensured.
In this invention, medium carbon steel, having substantially the
same work-hardening rate and thermal treatment characteristic as
the stainless steel wire employed as wire members, is adopted as
armoring material so that the wire members and armoring are
substantially uniform in composition, besides being tightly fitted
relative each other. Therefore, any breaking due to a difference
between inner stresses is prevented. Also, oxide films are produced
on the surfaces of the wire members through thermal treatment in an
oxidation atmosphere. Mutual burning of the wire members in a
drawing process is therefore prevented, and a perfect filament in
which the wire members are not welded relative to one another can
be obtained.
The two typical embodiments of the invention are described
below.
The first embodiment is related to a method of producing brushes of
stainless steel wire, by employing medium carbon steel S45C with a
cross section of 0.8.times. 15 mm..sup.2 for the armoring 6 in the
shape of a band, and 0.6 mm. stainless steel wire SUS27 for the
wire members 1. All of the stainless steel wires are extracted from
20 reels and gathered into a bundle, and made to pass through the
converging roll 2 and bound so as to be substantially in parallel
with one another. The armoring 6, on the other hand, wound around
the real 5 is introduced by the guide roll 7, made to pass through
the molding roll 9 and the bending roll 10 to be molded into the
shape of an upward-looking conduit, and supplied so as to accept
the wire members 1 in parallel with the wire members 1.
Therefore, the 20 wire members 1 and the armoring 6 are made to
advance through the wire drawing apparatus at the same speed.
The 20 wire members 1 and the band-shaped medium carbon steel
armoring 6 pass through the dies 14 having a 5.0 mm. caliber in the
parallel condition, forming a bundle of approximately 5.0 mm. as
they pass through the dies 14. The speed at which the armoring 6
and wire members 1 advance at that time is set at 2 m. per
minute.
An air-patenting treatment from 950.degree. C. in an oxidation
atmosphere is applied to the bundle thus obtained, and cold
machinability and lubricity are provided to the armoring 6, and
oxide films are formed on the surfaces of the wire members 1.
The bundle, further applied to the wire drawing apparatus having
suitably selected dies, is drawn with an average cross-sectional
decrease rate of 10 percent, and further drawn by stress-removing
low-temperature annealing under high tension and at a speed of 5 m.
per minute and at 600.degree. C. This procedure is reiterated, with
75 percent of total machining rate from one annealing to the next
annealing process. The bundle is cut into pieces of 120 cm., 50 of
said pieces being bound together. Their medium carbon steel
armoring is dissolved away in a solution containing 20 percent
nitric acid. Then, the oxide films of the wire members 1 are
removed with fluoronitric acid.
In a second typical embodiment, a bundle with an outer diameter of
5 mm. is composed of armoring 6 in the shape of a band and 300 wire
members 1 each having a diameter of 0.1 mm. The thermal treatment
and drawing processes are applied to the bundle in an oxidation
atmosphere as in the preceding embodiment. The annealing and
drawing processes are repeated six times and when the outer
diameter has become 3 mm., the armoring is removed from the wire
members 1 in the same way as in the foregoing embodiment, to obtain
a filament with a diameter of approximately 7 microns.
* * * * *