U.S. patent application number 16/094388 was filed with the patent office on 2020-06-18 for sewing machine needle clamping device.
The applicant listed for this patent is SUZUKI MANUFACTURING, LTD.. Invention is credited to TOHRU SAKUMA, MITSUHARU SUZUKI.
Application Number | 20200190716 16/094388 |
Document ID | / |
Family ID | 65527410 |
Filed Date | 2020-06-18 |
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United States Patent
Application |
20200190716 |
Kind Code |
A1 |
SAKUMA; TOHRU ; et
al. |
June 18, 2020 |
SEWING MACHINE NEEDLE CLAMPING DEVICE
Abstract
A sewing machine needle is attached, fixed or exchanged to a
needle clamp firmly and easily. The needle clamp 5 for clamping the
sewing machine needle 3 has an accommodating recessed part 7 which
accommodates a needle shank 15 of the sewing machine needle, a
clamp lever 19 which has a clamp arm 21 which engages to the needle
shank, is freely opened and closed end is fixed to a clamp lever
shaft 17 which is fitted loosely to an elongate hole 13b is bored
at the needle clamp for the accommodating recessed part a needle
clamp spring 23 which repels elastically the clamp lever to an
outer direction of a straight line which links a central point N of
the needle shank and a central point of the clamp lever shaft, and
the cam 71 is provided in the needle clamp 5, and the cam follower
70 which engages to the cam 71 is provided in the clamp arm 21, and
the elongate hole has three surfaces that the cam follower climbs
over the cam and moves as the movement path of the clamp lever
shaft which becomes a rotation center P of the clamp lever.
Inventors: |
SAKUMA; TOHRU; (YAMAGATA,
JP) ; SUZUKI; MITSUHARU; (YAMAGATA, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SUZUKI MANUFACTURING, LTD. |
YAMAGATA |
|
JP |
|
|
Family ID: |
65527410 |
Appl. No.: |
16/094388 |
Filed: |
August 29, 2017 |
PCT Filed: |
August 29, 2017 |
PCT NO: |
PCT/JP2017/030923 |
371 Date: |
October 17, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D05B 55/02 20130101 |
International
Class: |
D05B 55/02 20060101
D05B055/02 |
Claims
1. A sewing machine needle clamping device for attaching a sewing
machine needle to an accommodating recessed part of a needle clamp,
comprising: said needle clamp having, the accommodating recessed
part accommodating a needle shank of the sewing machine needle by
joining an attaching flat surface to a bottom portion, a swingable
clamp lever having a clamp arm engaging to the needle shank of said
sewing machine needle, being freely opened and closed for said
accommodating recessed part and being fixed to a clamp lever shaft
being fitted loosely into an elongate hole being bored at said
needle clamp, and a needle clamp spring repelling elastically said
clamp lever to an outer direction of a straight line linking a
central point of the needle shank of said sewing machine needle and
a central point of said clamp lever shaft, wherein said clamp arm
has a force acting locking part, moving around on a peripheral
surface of the needle shank of said sewing machine needle against
the elasticity of said needle clamp spring when swinging said clamp
lever to a clamping direction in the state that the needle shank of
said sewing machine needle is engaged to said accommodating
recessed part and butted against an attaching position of a
vertical direction, passing a branch point position that the
elasticity of said needle clamp spring becomes maximum, and holding
a stable clamping state by the elasticity of said needle clamp
spring, a cam is provided in said needle clamp, a cam follower
which engages to said cam is provided in said clamp arm, and said
elongate hole has three surfaces that said cam follower climbs over
said cam and moves as a movement path of said clamp lever shaft
which becomes a rotation center of said clamp lever.
2. A sewing machine needle clamping device according to claim 1,
wherein: a lock piece is provided in said needle clamp movably in a
direction which is perpendicular to the direction of an axis of
said needle, and a lock piece stopper which guides said lock piece
to a direction which is perpendicular to a direction of an axis of
said sewing machine needle is provided, a clamp stopper which
prevents the opening of said clamp lever by locking to said lock
piece when closing said clamp lever is provided in said clamp
lever, and a lock release button which releases the lock of said
lock piece and said clamp stopper when opening said clamp lever is
provided in said clamp lever.
3. A sewing machine needle clamping device for attaching a sewing
machine needle to an accommodating recessed part of a needle clamp,
comprising: said needle clamp having, the accommodating recessed
part accommodating a needle shank of the sewing machine needle by
joining an attaching flat surface to a bottom portion, a swingable
clamp lever having a clamp arm engaging to the needle shank of said
sewing machine needle, being freely opened and closed for said
accommodating recessed part and being fixed to a clamp lever shaft
being fitted loosely into an elongate hole being bored at said
needle clamp, and a needle clamp spring repelling elastically said
clamp lever to an outer direction of a straight line linking a
central point of the needle shank of said sewing machine needle and
a central point of said clamp lever shaft, wherein said clamp arm
has a force acting locking part, moving around on a peripheral
surface of the needle shank of said sewing machine needle against
the elasticity of said needle clamp spring when swinging said clamp
lever to a clamping direction in the state that the needle shank of
said sewing machine needle is engaged to said accommodating
recessed part and butted against an attaching position of a
vertical direction, passing a branch point position that the
elasticity of said needle clamp spring becomes maximum, and holding
a stable clamping state by the elasticity of said needle clamp
spring, said needle clamp which attaches said sewing machine needle
is formed in an inner shape which adjusts to said needle shank or
an outer shape of said needle to prevent that said needle slips out
of said needle clamp when said needle penetrates into a cloth and
then said needle come out of said cloth.
4. A sewing machine needle clamping device according to claim 3,
wherein: a needle clamp forgetting prevention spring which repels
elastically said needle to a direction that said needle separates
from said accommodating recessed part is provided in said needle
clamp which attaches said sewing machine needle when said clamp
lever is opened.
5. A sewing machine needle clamping device according to claim 1,
wherein: an attaching hole which adjusts to a D-shaped
cross-sectional shape including an attaching flat surface of an
upper end of said needle shank of said needle is formed to be able
to attach said sewing machine needle at the time of a direction of
the attachment of said needle where said attaching flat surface of
said needle shank is joined to said attaching flat surface of said
accommodating recessed part in said needle clamp which attaches
said sewing machine needle.
6. A sewing machine needle clamping device according to claim 3,
wherein: an attaching hole which adjusts to a D-shaped
cross-sectional shape including an attaching flat surface of an
upper end of said needle shank of said needle is formed to be able
to attach said sewing machine needle at the time of a direction of
the attachment of said needle where said attaching flat surface of
said needle shank is joined to said attaching flat surface of said
accommodating recessed part in said needle clamp which attaches
said sewing machine needle.
Description
FIELD OF THE ART
[0001] The present invention relates to a sewing machine needle
clamping device, and particularly relates to the sewing machine
needle clamping device for attaching, fixing or exchanging a sewing
machine needle of such as a lock stitch sewing machine, a serger, a
double chain stitch sewing machine, or a cover stitch sewing
machine to a needle clamp firmly and easily.
BACKGROUND OF THE ART
[0002] Conventionally, in the lock stitch sewing machine, the
serger, the double chain stitch sewing machine, or the cover stitch
sewing machine, etc., it is well known that a cloth which should be
sewed is sandwiched between a throat plate and a presser foot which
is pressed by a presser bar and is fed stitch by stitch by a feed
dog mechanism, and stitches are formed on the cloth by the sewing
machine needle and a shuttle hook or a looper as a loop capturing
device.
[0003] In the meantime, the shuttle hook or the looper as the loop
capturing device and the feed dog mechanism are driven by each
drive mechanism from a lower shaft which is a drive shaft. On the
other hand, the sewing machine needle is screwed by a screw to the
needle clamp which is attached to the needle bar which is driven
with an upper shaft which is transferred from the lower shaft by a
lower shaft pulley, a timing belt and an upper shaft pulley (cf:
Patent document Nos. 1-4).
PRIOR ART DOCUMENT
Patent Document
[0004] [Patent document No. 1] JP H05-085380 U [Patent document No.
2] JP 2004-121280 A [Patent document No. 3] JP 2007-151777 A
[Patent document No. 4] JP 3181298 U
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0005] However, in such the sewing machine needle clamping device,
on the one hand, while holding a sewing machine needle shank at an
attaching position of vertical direction in an inside of the needle
clamp, on the other hand, it is necessary to screw the sewing
machine needle by the screw to the needle clamp by joining and
holding an attaching flat surface which is provided on a peripheral
surface of the sewing machine needle shank to an attaching flat
surface of the inside of the needle clamp. In this case, an
operation which is necessary to screw one or multiple sewing
machine needles by the screw to each needle clamp by joining and
holding to the attaching flat surface of the inside of the needle
clamp firmly by a screwdriver is a complicated work for operators
of the sewing machine.
[0006] The present invention was conducted to solve these
disadvantages. The object of the present invention is to provide
the sewing machine needle clamping device that such the operation
which has to screw the sewing machine needle by the screw to the
needle clamp firmly by a screwdriver is unnecessary and the
mechanism is simplified and the operation is performed by one-touch
operation and the sewing machine needle of the sewing is attached
and fixed to the needle clamp firmly and easily.
Means for Solving the Problems
[0007] In order to achieve such the objects, a sewing machine
needle clamping device of the present invention for attaching a
sewing machine needle to an accommodating recessed part of a needle
clamp comprises the needle clamp which has, [0008] the
accommodating recessed part which accommodates a needle shank of
the sewing machine needle by joining an attaching flat surface to a
bottom portion, [0009] a swingable clamp lever which has a clamp
arm which engages to the needle shank of the sewing machine needle
and is freely opened and closed for the accommodating recessed part
and is fixed to a clamp lever shaft which is fitted loosely into an
elongate hole which is bored at the needle clamp, and [0010] a
needle clamp spring which repels elastically the clamp lever to an
outer direction of a straight line which links a central point of
the needle shank of the sewing machine needle and a central point
of the clamp lever shaft, wherein
[0011] the clamp arm has a force acting locking part, which moves
around on a peripheral surface of the needle shank of the sewing
machine needle against the elasticity of the needle clamp spring
when swinging the clamp lever to a clamping direction in the state
that the needle shank of the sewing machine needle is engaged to
the accommodating recessed part and butted against an attaching
position of a vertical direction, and passes a branch point
position that the elasticity of the needle clamp spring becomes
maximum, and holds a stable clamping state by the elasticity of the
needle clamp spring, and
[0012] a cam is provided in the needle clamp, a cam follower which
engages to the cam is provided in the clamp arm, and
[0013] the elongate hole has three surfaces that the cam follower
climbs over the cam and moves as a movement path of the clamp lever
shaft which becomes a rotation center of the clamp lever.
[0014] Besides, in the sewing machine needle clamping device of the
present invention, a lock piece is provided in the needle clamp
movably in a direction which is perpendicular to the direction of
an axis of the needle, and a lock piece stopper which guides the
lock piece to a direction which is perpendicular to a direction of
an axis of the sewing machine needle is provided, a clamp stopper
which prevents the opening of the clamp lever by locking to the
lock piece when closing the clamp lever is provided in the clamp
lever, and a lock release button which releases the lock of the
lock piece and the clamp stopper when opening the clamp lever is
provided in the clamp lever.
[0015] Besides, a sewing machine needle clamping device of the
present invention for attaching a sewing machine needle to an
accommodating recessed part of a needle clamp comprises the needle
clamp which has, [0016] the accommodating recessed part which
accommodates a needle shank of the sewing machine needle by joining
an attaching flat surface to a bottom portion, [0017] a swingable
clamp lever which has a clamp arm which engages to the needle shank
of the sewing machine needle and is freely opened and closed for
the accommodating recessed part and is fixed to a clamp lever shaft
which is fitted loosely into an elongate hole which is bored at the
needle clamp, and [0018] a needle clamp spring which repels
elastically the clamp lever to an outer direction of a straight
line which links a central point of the needle shank of the sewing
machine needle and a central point of the clamp lever shaft,
wherein
[0019] the clamp arm has a force acting locking part, which moves
around on a peripheral surface of the needle shank of the sewing
machine needle against the elasticity of the needle clamp spring
when swinging the clamp lever to a clamping direction in the state
that the needle shank of the sewing machine needle is engaged to
the accommodating recessed part and butted against an attaching
position of a vertical direction, and passes a branch point
position that the elasticity of the needle clamp spring becomes
maximum, and holds a stable clamping state by the elasticity of the
needle clamp spring, and
[0020] the needle clamp which attaches the sewing machine needle is
formed in an inner shape which adjusts to the needle or an outer
shape of the needle to prevent that the needle slips out of the
needle clamp when the needle penetrates into a cloth and then the
needle come out of the cloth.
[0021] Besides, in the sewing machine needle clamping device of the
present invention, a needle clamp forgetting prevention spring
which repels elastically the needle to a direction that the needle
separates from the accommodating recessed part is provided in the
needle clamp which attaches the sewing machine needle when the
clamp lever is opened.
[0022] Besides, in the sewing machine needle clamping device of the
present invention, an attaching hole which adjusts to a D-shaped
cross-sectional shape including an attaching flat surface of an
upper end of the needle shank of the sewing machine needle is
formed to be able to attach the sewing machine needle at the time
of a direction of the attachment of the needle where the attaching
flat surface of the needle shank is joined to the attaching flat
surface of the accommodating recessed part in the needle clamp
which attaches the sewing machine needle.
Effect of the Invention
[0023] According to a sewing machine needle clamping device of the
present invention, this device can provide the basic merits that
the mechanism is simplified and the operation is performed by
one-touch operation of small number of times, and the sewing
machine needle of such as the lock stitch sewing machine, the
serger, the double chain stitch sewing machine, or the cover stitch
sewing machine can be attached, fixed or exchanged to the needle
clamp firmly and easily.
[0024] According to the sewing machine needle clamping device of
the present invention, in addition to the above basic merits, when
the sewing machine needle is clamped, the wear-out due to the
engagements of many times of the needle shank face that a maker
name of the sewing machine needle and an engraved mark are engraved
and a force acting locking part face of the clamp arm is
eliminated, and the sewing machine needle can be clamped to the
needle clamp certainly.
[0025] According to the sewing machine needle clamping device of
the present invention, in addition to the above basic merits, when
the clamp lever is closed, the clamp lever is opened by the
unintentional movement in the lateral direction and the
back-and-forth direction of the needle and the malfunction that
clamping of the needle is released occurs, and this device can
function as a safety device which prevents that the sewing machine
needle breaks and disperses by the collision with other parts.
[0026] According to the sewing machine needle clamping device of
the present invention, in addition to the above basic merits, when
the sewing machine needle penetrates into the cloth that the needle
is hard to pierce, in other words, when the sewing machine needle
penetrates into the cloth which has the large friction and then the
sewing machine needle come out of the cloth, this device can
prevent that the sewing machine needle slips out of the needle
clamp by the frictional force with the cloth.
[0027] According to the sewing machine needle clamping device of
the present invention, in addition to the above basic merits, when
the needle is attached to the needle clamp, the safety device which
does not drop the sewing machine needle is provided. On the other
hand, when the clamp lever is opened, prevention to forget clamping
can be attempted because the sewing machine needle drops from the
accommodating recessed part.
[0028] According to the sewing machine needle clamping device of
the present invention, in addition to the above basic merits, the
sewing machine needle can be attached to the accommodating recessed
part only when a direction of the sewing machine needle where the
attaching flat surface of the needle shank is joined to the
attaching flat surface of the accommodating recessed part is
attached, and the attachment can be performed certainly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 A whole perspective view seeing from a front side of
the sewing machine which attaches the sewing machine needle
clamping device by the present invention.
[0030] FIG. 2 (a) A front view of the sewing machine needle
clamping device of the present invention which clamps the sewing
machine needle to the needle clamp.
[0031] FIG. 2 (b) A bottom view of the sewing machine needle
clamping device by the present invention which clamps the sewing
machine needle to the needle clamp.
[0032] FIG. 2 (c) A back view of the sewing machine needle clamping
device by the present invention which clamps the sewing machine
needle to the needle clamp.
[0033] FIG. 2 (d) A perspective view of the sewing machine needle
clamping device by the present invention which clamps the sewing
machine needle to the needle clamp.
[0034] FIG. 3 (a) is an exploded perspective view of the sewing
machine needle clamping device by the present invention, and (b) is
a partial perspective view of the sewing machine needle clamping
device seeing from a direction of an arrow A of (a).
[0035] FIG. 4 (a) A bottom view of the sewing machine needle
clamping device by the present invention in a state before clamping
the sewing machine needle to the needle clamp.
[0036] FIG. 4 (b) A bottom view of the sewing machine needle
clamping device by the present invention in a state immediately
after clamping operation of the sewing machine needle to the needle
clamp.
[0037] FIG. 4 (c) A bottom view of the sewing machine needle
clamping device by the present invention in a state after further
continuing a clamping operation of the sewing machine needle to the
needle clamp.
[0038] FIG. 4 (d) A bottom view of the sewing machine needle
clamping device by the present invention in a state which completed
a clamping operation of the sewing machine needle to the needle
clamp.
[0039] FIG. 5 (a) A motion schematic view of the sewing machine
needle clamping device by the present invention in a state before
clamping the sewing machine needle to the needle clamp.
[0040] FIG. 5 (b) A motion schematic view of the sewing machine
needle clamping device by the present invention in a state
immediately after clamping operation of the sewing machine needle
to the needle clamp.
[0041] FIG. 5 (c) A motion schematic view of the sewing machine
needle clamping device by the present invention in a state after
further continuing a clamping operation of the sewing machine
needle to the needle clamp.
[0042] FIG. 5 (d) A motion schematic view of the sewing machine
needle clamping device by the present invention in a state which
completed a clamping operation of the sewing machine needle to the
needle clamp.
[0043] FIG. 5 (e) An explanatory view showing the movement path of
the clamp lever shaft in the elongate hole which is provided in the
needle clamp of the sewing machine needle clamping device by the
present invention. A bottom view and a partial enlarged view of the
clamping device.
[0044] FIG. 6 (a) A bottom view of the sewing machine needle
clamping device of the present invention which clamps the sewing
machine needle to the needle clamp certainly and prevents the clamp
release.
[0045] FIG. 6 (b) A bottom view of the sewing machine needle
clamping device of the present invention which clamps the sewing
machine needle to the needle clamp certainly and prevents the clamp
release.
[0046] FIG. 6 (c) A bottom view of the clamping device of the
present invention which clamps the sewing machine needle to the
needle clamp certainly and prevents the clamp release.
[0047] FIG. 6 (d) A perspective view of the sewing machine needle
clamping device of the present invention which clamps the sewing
machine needle to the needle clamp certainly and prevents the clamp
release.
[0048] FIG. 7 A partial enlarged view of the front view of the
sewing machine needle clamping device of the present invention
which clamps the sewing machine needle to the needle clamp
certainly and prevents the needle from slipping out.
[0049] FIG. 8 (A) A front view of the sewing machine needle
clamping device of the present invention which prevents forgetting
clamping of the sewing machine needle.
[0050] FIG. 8 (b) A perspective view of the sewing machine needle
clamping device of the present invention which prevents forgetting
clamping of the sewing machine needle.
[0051] FIG. 9 (a) A bottom view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
[0052] FIG. 9 (b) A bottom view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
[0053] FIG. 9 (c) A bottom view of the sewing machine needle
clamping device the present invention which performs an orientation
work of the sewing machine needle certainly when clamping the
sewing machine needle to the needle clamp certainly.
[0054] FIG. 9 (d) A bottom view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
[0055] FIG. 9 (e) A perspective view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
[0056] FIG. 9 (f) A perspective view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
[0057] FIG. 9 (g) A bottom view of the sewing machine needle
clamping device of the present invention which performs an
orientation work of the sewing machine needle certainly when
clamping the sewing machine needle to the needle clamp
certainly.
MODE FOR CARRYING OUT THE INVENTION
[0058] Hereinafter, the some preferable embodiments that the sewing
machine needle clamping device of the present invention is applied
to a 2 (two) needles 4 (four) threads serger (hemstitch sewing
machine) are captained in detail by referring to the drawings.
[0059] As shown in FIG. 1, in this 2 needles 4 threads hemstitch
sewing machine (serger) 40, the cloth which should be sewed is
sandwiched between the throat plate 42 and the presser foot which
is pressed by the presser bar and is fed stitch by stitch by the
feed dog mechanism, and stitches are formed on the cloth by the
sewing machine needle 3 and the looper 44 as the loop capturing
device.
[0060] This looper 44 as the loop capturing device and the feed dog
mechanism are driven by each drive mechanism from the lower shaft
46 which is the drive shaft. On the other hand, the sewing machine
needle 3 is fixed to the needle clamp 5 which is attached to the
needle bar 58 which is driven by a needle bar drive mechanism 56
with the upper shaft 54 which is transmitted from the lower shaft
46 with rotation ratio of 1:1 by the lower shaft pulley 48, the
timing belt 50 and the upper shaft pulley 52. The upper shaft 54
the needle bar drive mechanism 56 are attached to a sewing arm. The
throat plate 42, the looper 44 as the loop capturing device and the
feed dog mechanism are attached to a sewing bed.
[0061] According to such the 2 needles and 4 threads hemstitch
sewing machine (serger) 40, the cloth which should be sewed is
sandwiched between the throat plate 42 and the presser foot which
is pressed by the presser bar and is fed stitch by stitch by the
feed dog mechanism, and stitches are formed on the cloth by the
sewing machine needle 3 and the looper 44 as the loop capturing
device. However, because the number, the specific structure and the
operation of the throat plate 42 and the looper 44 as the loop
capturing device for forming the stitches are public known or well
known, the detailed explanations are emitted.
[0062] As shown in FIG. 2 (a)-FIG. 2 (d), FIG. 3, FIG. 4 (a)-FIG. 4
(d) and FIG. 5 (a)-FIG. 5 (d), a feature of the present invention
resides in the sewing machine needle clamping device 1 which
attaches the sewing machine needle 3 to the accommodating recessed
part 7 of the needle clamp 5. The needle clamp 5 has a fixing
cylindrical portion 11 that the needle clamp 5 is fitted into the
needle bar 58 and attached by the screw 9 and an attaching base 13
which extends from it up and down integrally. In addition, as this
embodiment, although the needle clamp 5 may be attached as a
separate part from the needle bar 58, the needle clamp 5 may be
formed to and attached to the needle bar 58 integrally. The needle
clamp 5 above-mentioned accommodating recessed part 7 which
accommodates the needle shank 15 of the sewing machine needle 3 in
a central attaching portion 13c in the attaching base 13. The
accommodating recessed part 7 and the attaching base 13 of the
needle clamp 5 are arranged symmetrically one by one with respect
to s central longitudinal section of the needle clamp 5.
[0063] In two sewing machine needles 3, an end face of the shank of
the needle shank 15 is butted against different attaching position
of vertical direction in the inside of the needle clamp 5
respectively and an attaching flat surface 15a which is provided at
the peripheral surface of the needle shank 15 of the sewing machine
needle 3 is joined to an attaching flat surface 7a of the
accommodating recessed part 7 in the inside of the needle clamp
5.
[0064] The needle clamp 5 has a clamp lever 19 which is freely
opened and closed and is fixed to a clamp lever shaft 17 which is
pivotally attached to an elongate bole 13b which is bored at an
attaching portion 13a which is provided up and down in the
attaching base 13 of the needle clamp 5 for the accommodating
recessed part 7. When the clamp lever shaft 17 is pivotally
attached in the elongate hole 13b, it can pivotally move, and is
stopped so that it cannot move in the vertical direction. An
elongate direction of the elongate hole 13b is same direction as a
straight line L2 which links a central point N of the needle shank
15 of the sewing machine needle 3 which is accommodated in the
accommodating recessed part 7 of the needle clamp 5 and a central
point P of the clamp lever shaft 17 (FIG. 5 (a)). The clamp lever
19 has a clamp arm 21 which moves around without contacting on the
peripheral surface of the needle shank 15 of the sewing machine
needle 3.
[0065] In addition, the elongate hole 13b is formed in a deformed
elongate hole and has three surfaces 13d, 13e, 13f that the cam
follower 70 climbs over the cam 71 and moves as the movement path
of the clamp lever shaft 17 which becomes the rotation center P of
the clamp lever 19 (FIG. 5 (e)). The central point P of the clamp
lever shaft 17 traces the central points P1, P2, P3 in the inside
of the deformed elongate hole 13b. The three surfaces 13d, 13e, 13f
intervene between arc surfaces 13g, 13h, 13i which are formed with
same diameters as a radius "r" of the clamp lever shaft 17. As for
these configurations of elongate holes 13b, the details are
described later.
[0066] Besides, the needle clamp 5 has a plate-like needle clamp
spring 23 which repels elastically the clamp lever 19 to an outer
direction of the straight line which links the central point N of
the needle shank 15 of the sewing machine needle 3 and the central
point P of the clamp lever shaft 17.
[0067] In the sewing machine needle clamping device 1, the clamp
arm 21 has a force acting locking part 22,
[0068] which moves around without contacting on the peripheral
surface of the needle shank 15 of the sewing machine needle 3
against the elasticity of the needle clamp spring 23 when swinging
the clamp lever 19 to a clamping direction "a" (FIG. 4 (b)-FIG. 4
(d), FIG. 5 (a)-FIG. 5 (d)) in the state that the needle shank 15
of the sewing machine needle 3 is engaged to the accommodating
recessed part 7 and butted against the attaching position 7b (FIG.
2 (a)) of the vertical direction, and
[0069] which passes a branch point position tp (FIG. 5 (c)) that
the elasticity of the needle clamp spring 23 becomes maximum,
and
[0070] which holds a stable clamping state by the elasticity of the
needle clamp spring 23.
[0071] According to the sewing machine needle clamping device 1 of
the present invention which is composed in this way, in the state
before clamping the sewing machine needle 3 to the needle 5, the
needle shank 15 of the sewing machine needle 3, the clamp lever
shaft 17 of the needle clamp 5 and the clamp arm 21 of the clamp
lever 19 are positional relations shown in FIG. 4 (a).
[0072] According to the sewing machine needle clamping device 1 of
the present invention, for example, the end face of the shank of
the needle shank 15 of the sewing machine needle 3 is butted
against different attaching position of vertical direction in the
inside of the needle clamp 5 and the attaching flat surface 15a
which is provided at the peripheral surface of the needle shank 15
of the sewing machine needle 3 is joined to the attaching flat
surface 7a of the accommodating recessed part 7 in the inside of
the needle clamp 5 by left hand, and in the state immediately after
clamping the clamp lever 19 to the clamping direction "a" by right
hand, the clamp lever shaft 17 is repelled elastically and pressed
to a hole surface of outside direction of the elongate hole 13b in
the direction of the straight line which links the central point N
of the needle shank 15 of the sewing machine needle 3 and the
central point P of the clamp lever shaft 17 by the needle clamp
spring 23 (FIG. 5 (b)).
[0073] According to the sewing machine needle clamping device 1 of
the present invention, the end face of the shank of the needle
shank 15 of the sewing machine needle 3 is butted against the
attaching position of the vertical direction in the inside of the
needle clamp 5 and the attaching flat surface 15a which is provided
at the peripheral surface of the needle shank 15 of the sewing
machine needle 3 is joined to the attaching flat surface 7a of the
accommodating recessed part 7 in the inside of the needle clamp 5,
and in the state after further continuing the clamping operation of
the clamp lever 19 to the direction of the arrow "a", the tip 21a
of the clamp arm 21 of the clamp lever 19, that is the force acting
locking part 22 resists elastic repulsion of the needle clamp
spring 23 for climbing over the needle shank 15 of the sewing
machine needle 3 and moves to the direction of the needle shank 15
of the sewing machine needle 3 in the inside of the elongate hole
13b (FIG. 5 (b)).
[0074] According to the sewing machine needle clamping device 1 of
the present invention, in the state that the end face of the shank
of the needle shank 15 of the sewing machine needle 3 is butted
against the attaching position of the vertical direction in the
inside of the needle clamp 5, the attaching flat surface 15a which
is provided at the peripheral surface of the needle shank 15 of the
sewing machine needle 3 is joined to the attaching flat surface 7a
of the accommodating recessed part 7 in the inside of the needle
clamp 5 and completed the clamping operation of the clamp lever 19
to the direction of the arrow "a", in other words, in the clamping
state, if the tip 21a of the clamp arm 21 of the clamp lever 19,
that is, if the force acting locking part 22 climbs over the branch
point position tp that elastic force of the needle clamp spring 23
becomes maximum, the curvature of the needle shank 15 of the sewing
machine needle 3 and the curvature of the clamp arm 21 of the clamp
lever 19 are corresponding, thereby the clamp lever shaft 17
returns toward the hole surface of outside direction of the
elongate hole 13b in the direction of the straight line which links
the central point N of the needle shank 15 of the sewing machine
needle 3 and the central point P of the clamp lever shaft 17, and
the central point C of the engagement surface 21b of the clamp arm
21 and the central point N of the needle shank 15 of the sewing
machine needle 3 are corresponding (FIG. 5 (d)). As a result, the
force F which repels elastically and presses the clamp lever shaft
17 to the direction of the central point N of the needle shank
15--the central point P of the clamp lever shaft 17 operates and
the sewing machine needle 3 is fixed stably by the needle clamp
spring 23. The stable clamping state is held in this positional
relation. As shown in FIG. 4 (d), in this state, the sewing machine
needle 3, the needle clamp 5 and the clamp lever 19 are composed as
sizes that the straight line L1 which links the central point C of
the engagement surface 21b of the clamp arm 21 and the central
point P of the clamp lever shaft 17 is corresponding to the
straight line L2 which links the central point N of the needle
shank 15 of the sewing machine needle 3 and the central point P of
the clamp lever shaft 17. In addition, in other words, in this
state, in the needle shank 15 of the sewing machine needle 3, the
clamp lever shaft 17 of the needle clamp 5 and the clamp arm 21 of
the clamp lever 19, the distance L1 which links the central point C
of the engagement surface 21b of the clamp arm 21 and the central
point P of the clamp lever shaft 17 is corresponding to the
distance L2 which links the central point N of the needle shank of
the sewing machine needle and the central point P of the clamp
lever shaft. That is, it becomes L1=L2 (FIG. 5 (d)).
[0075] in the abovementioned sewing machine needle clamping device
1, when the sewing machine needle is clamped, surface friction of
each other is caused due to the engagements of many times of the
face of the needle shank 15 that the maker name of the sewing
machine needle 3 and the engraved mark are engraved and the convex
part of the force acting locking part 22 of the clamp arm 21 and
due to the difference between the materials of both at the time of
the engagement, eventually, there is a possibility that the sewing
machine needle 3 cannot be clamped to the needle clamp 5
certainly.
[0076] In the sewing machine needle clamping device 1 of the
present invention, in order to eliminate the abovementioned
disadvantages, as a premise, as mentioned above, the needle clamp 5
has the clamp lever 19 which is freely opened and closed for the
accommodating recessed part 7 and is fixed to the clamp lever shaft
17 which is pivotally attached to the elongate hole 13b which is
bored at the attaching portion 13a is provided up and down in the
attaching base 13 of the needle clamp 5. The clamp lever 19 has a
clamp arm 21 which moves around without contacting on the
peripheral surface of the needle shank 15 of the sewing machine
needle 3. The clamp arm 21 has the force acting locking part 22,
which moves around without contacting on the needle shank 15 of the
sewing machine needle 3 against the elasticity of the needle clamp
spring 23 when swinging the clamp lever 19 to a clamping direction
"a" (FIG. 4 (b)-FIG. 4 (d), FIG. 5 (a)-FIG. 5 (d)) in the state
that the needle 15 of the sewing machine needle 3 is engaged to the
accommodating recessed part 7 and butted against the attaching
position 7b (FIG. 2 (a)) of the vertical direction, and which
passes the branch point position tp (FIG. 5 (c)) that the
elasticity of the needle clamp 23 becomes maximum, and which holds
the stable clamping state by the elasticity of the needle clamp
spring 23.
[0077] Besides, as shown in FIG. 4 (a)-FIG. 4 (d), FIG. 5 (a)-FIG.
5 (d), according to the sewing machine needle clamping device of
the present invention, the cam 71 is provided in the needle clamp
5, the cam follower 70 which engages to the cam 71 is provided in
the clamp arm 21, the elongate hole 13b is formed in the deformed
elongate hole and has three surfaces 13d, 13e, 13f that the cam
follower 70 climbs over the cam 71 and moves as the movement path
of the clamp lever shaft 17 which becomes the rotation center P of
the clamp lever 19 (FIG. 5 (e)). The central point P of the clamp
lever shaft 17 traces the central points P1, P2, P3 in the inside
of the deformed elongate hole 13b. The three surfaces 13d, 13e, 13f
intervene between arc surfaces 13g, 13h, 13i which are formed with
same diameters as the radius "r" of the clamp lever shaft 17. In
this way, the deformed elongate hole 13b is formed with the three
surfaces 13d, 13e, 13f and inner peripheral surfaces of the arc
surfaces 13g, 13h, 13i. Depending on closing of the clamp lever 19,
according to the engagement between the cam follower 70 and the cam
71 and elastic repulsion of the needle clamp spring 23, the central
point P of the clamp lever shaft 17 passes the central points P1,
P2 in the inside of the deformed elongate hole 13b and reaches a
neighborhood of the central point P3, and reaches the central point
P3 when the needle shank 15 of the sewing machine needle 3 is not
attached to the accommodating recessed part 7 of the needle clamp
5, on the other hand, the clamp lever shaft 17 is designed to trace
three surfaces 13d, 13e, 13f as its movement path. In addition,
depending on opening of the clamp lever 19, the central point P of
the clamp lever shaft 17 moves the central points P3, P2, P1 in the
inside of the deformed elongate hole 13b conversely.
[0078] In this case, the above force acting locking part 22 passes,
and the branch point position tp where the elasticity of the needle
clamp spring 23 which holds the stable clamping state by the
elasticity of the needle clamp spring 23 becomes maximum is a
contact point between the cam follower 70 and the cam 71 when the
central point P3 in the elongate hole 13b and the central point P
of the clamp lever shaft 17 correspond. However, practically, to
allow that the clamp lever shaft 17 moves smoothly, the central
point P3 is provided with a certain clearance L3 toward the central
point N from the central point P on the straight line L2 linking
the central point N of the needle shank 15 and the central point P
of the clamp lever shaft 17 (FIG. 5 (c)).
[0079] In this sewing machine needle clamping device 1, when
swinging the clamp lever 19 at the time of clamping the sewing
machine needle 3, till the state after continuing further clamping
the sewing machine needle 3 to the needle clamp 5 via the state
immediately after clamping the sewing machine needle 3 to the
needle clamp 5 from the state before clamping the sewing machine
needle 3 to the needle clamp 5, as the movement path of the clamp
lever shaft 17 which becomes the rotation centers P1, P2 of the
clamp lever 19 of the elongate hole 13b, the clamp lever shaft 17
moves the two surfaces 13d, 13e (FIG. 5 (a), FIG. 5 (b), FIG. 5
(c)) whose central points P1, P2 of the elongate hole 13b that the
cam follower 70 climbs over the cam 71 are curvature radii, and on
the other hand, because the cam follower 70 of the clamp arm 21
engages to the cam 71 of the needle clamp 5 (FIG. 4 (a), FIG. 4
(b), FIG. 4 (c)) and moves, the needle shank 15 of the sewing
machine needle 3 and the clamp arm 21 do not contact, and in state
which completes clamping the sewing machine needle 3 to the needle
clamp 5, the elongate hole 13b reaches the surfaces 13d, 13e, 13f
(FIG. 5 (a), FIG. 5 (b), FIG. 5 (c), FIG. 5 (d)) that the cam
follower 70 climbs over the cam 71 and moves as the movement path
of the clamp lever shaft 17 which becomes the rotation center P3 of
the clamp lever 19, and engages to the needle shank 15 of the
sewing machine needle 3 and the clamp arm 21 closely.
[0080] According to this sewing machine needle clamping device 1,
this device can provide the basic merits that the mechanism is
simplified and the operation is performed by one-touch operation of
small number of times, and the sewing machine needle of such as the
lock stitch sewing machine, the serger, the double stitch sewing
machine, or the cover stitch sewing machine can be attached, fixed
or exchanged to the needle clamp firmly and easily, and in addition
to the above basic merits, when the sewing machine needle is
clamped, the wear-out due to the engagements of many times of the
needle shank face that a maker name of the sewing machine needle
and an engraved mark are engraved and a force acting locking part
face of the clamp arm is eliminated, and the sewing machine needle
can be clamped to the needle clamp certainly.
[0081] Besides, as shown in FIG. 6 (a)-FIG. 6 (d), in the sewing
machine needle clamping device 1 of the present invention, a lock
piece 72 is provided in the needle clamp 5 movably in the direction
which is perpendicular to the direction of the axis of the sewing
machine needle 3, and a lock piece stopper 73 which guides lock
piece 72 to the direction which is perpendicular to the direction
of the axis of the sewing machine needle 3 is provided. A clamp
stopper 74 which prevents the opening of the clamp lever 19 by
locking to the lock piece 72 when closing the clamp lever 19 is
provided in the clamp lever 19, and a lock release button 75 which
is housed slidably in the clamp lever 19 and releases the lock of
the lock piece 72 and the clamp stopper 74 when opening the clamp
lever 19 is provided in the clasp lever 19. The lock piece 72 is
pressed to the clamp side by a coil spring 72a.
[0082] When the clamp lever 19 places in the clamp position, the
lock piece 72 is locked to the clasp stopper 74, and the clamp
lever 19 cannot be released (FIG. 6 (a)-FIG. 6 (b)). The lock piece
72 is released from the lock stepper 74 by pressing the lock
release button 75 to the lever and the clamp can be opened (FIG. 6
(c)-FIG. 6 (d)).
[0083] According to the sewing machine needle clamping device 1 of
the present invention, in addition to the above basic merits, when
the clamp lever 19 is closed, the clamp lever 19 is opened by the
unintentional movement in the lateral direction and/or the
back-and-forth direction of the sewing machine needle 3 and the
malfunction that clamping of the needle is released occurs, and
this device can function as a safety device which prevents that the
sewing machine needle 3 breaks and disperses by the collision to
other parts.
[0084] Besides, as shown in FIG. 2 (a), FIG. 7, in the sewing
machine needle clamping device 1 of the present invention which
attaches the sewing machine needle 3 to the accommodating recessed
part 7 of the needle clamp 5, the needle clamp 5 which attaches the
sewing machine needle 3 is formed in the outer shape of the needle
shank 15 of the sewing machine needle, especially is formed in the
inner shape 77 which adjusts to a shank taper 76 to prevent that
the sewing machine needle slips out of the needle clamp 5 when the
sewing machine needle 3 penetrates into the cloth which is used for
a sports bag which is coated by such as PVC or PU on the cloth or
leather that the needle is hard to pierce, in other words, when the
sewing machine needle 3 penetrates into the cloth which has the
large friction and then the sewing machine needle 3 come out of the
cloth.
[0085] Generally, when the sewing machine needle 3 penetrates into
the cloth that the needle is hard to pierce, and then the sewing
machine needle 3 come out of the cloth, the force works in the
direction which slips out from the needle clamp 5 by the frictional
force with the cloth. Although the inner shape 77 of a taper groove
of approximate shape with the shank taper 76 of the sewing machine
needle 3 is provided in an outlet side of a needle attaching groove
of the needle clamp 5, this is a taper shape which is clearance in
the extent that a timing position that a needle eye position scoops
a needle thread by a lower looper loop-taker point does not
influence even if the sewing machine needle 3 moves to the
direction of slipping out.
[0086] According to the sewing machine needle clamping device 1 of
the present invention, in addition to the above basic merits, when
the sewing machine needle penetrates into the cloth that the needle
is hard to pierce, in other words, when the sewing machine needle
penetrates into the cloth which has the large friction, and then
the sewing machine needle come out of the cloth, this device can
prevent that the sewing machine needle slips out of the needle
clamp by the frictional force with the cloth.
[0087] Besides, as shown in FIG. 8 (a), FIG. 8 (b), in the sewing
machine needle clamping device 1 of the present invention, when the
clamp lever 19 is opened, a L-shaped needle clamp forgetting
prevention spring 78 which repels elastically the sewing machine
needle 3 to the direction that the sewing machine needle 3
separates from the accommodating recessed part 7 is provided in the
needle clamp 5 which attaches the sewing machine needle 3.
[0088] As mentioned above, because the inner shape 77 of the taper
groove of approximate shape with the shank taper 76 of the sewing
machine needle 3 is provided as the taper for preventing the needle
from slipping out in the outlet side of the needle attaching groove
of the needle clamp 5, the sewing machine needle 3 does not fall
off when attaching the sewing machine needle 3 to the needle clamp
5. Therefore, there is a possibility to forget a clamping
operation. When the clamping operation is not performed, because
the sewing machine needle 3 is pushed out in the direction which
detaches from the taper groove by repelling elastically the sewing
machine needle 3 from a back side of the sewing machine needle 3,
the sewing machine needle 3 falls off.
[0089] According to the sewing machine needle clamping device 1 of
the present invention, in addition to the above basic merits, when
the sewing machine needle 3 is attached to the needle clamp 5, the
safety device which does not drop the sewing machine needle 3 is
provided. On the other hand, when the clamp lever 19 is opened,
clamping forgetting prevention can be attempted because the sewing
machine needle 3 drops from the accommodating recessed part 7.
[0090] Besides, as shown in FIG. 9 (a)-FIG. 9 (g), in the sewing
machine needle clamping device 1 of the present invention, the
needle clamp 5 which attaches the sewing machine needle 3 is
composed to be able to attach the sewing machine needle 3 at the
time of the direction of the attachment of the sewing machine
needle 3 where the attaching hole 80 which adjusts to a D-shaped
cross-sectional shape 79 including the attaching flat surface 15a
of the upper end of the needle shank 15 of the sewing machine
needle 3 is formed and the attaching flat surface 15a of the needle
shank 15 is joined to the attaching flat surface 7a of the
accommodating recessed part 7. In addition, when the upper end of
the needle shank 15 of the sewing machine needle 3 is not fitted
into the attaching hole 80 of the shape which adjusts to the
D-shaped cross-sectional shape 79 including the attaching flat
surface 15a, because the shank taper 76 of the sewing machine
needle 3 does not fit into the portion of the inner shape 77 of the
needle clamp 5, the sewing machine needle 3 cannot be attached to
the accommodating recessed part 7 at this point (FIG. 9 (e)-FIG. 9
(g)).
[0091] That is, in the direction of the attachment of the sewing
machine needle 3, the shank surface becomes the needle clamp body
side. In the attaching hole 80 of the needle clamp 5, because the
portion where the upper end of the needle shank 15 enters becomes
the D-shaped cross-sectional shape 79, in the case that the needle
shank 15 is not a normal direction, as mentioned above, the sewing
machine needle 3 cannot fit into the attaching hole 80 and force
acting locking part (clamp tip) 22 cannot also dish over the needle
shank 15, thereby the clamping operation cannot be performed.
[0092] However, when the direction of the attaching flat surface
15a of the needle shank 15 of the sewing machine needle 3 is the
position which is shown in FIG. 9 (a)-FIG. 9 (e), in also the case
that the needle shank 15 of the sewing machine needle 3 is not
fitted into the attaching hole 80 and is not fitted into the
attaching flat surface 7a of the accommodating recessed part 7 of
the needle clamp 5 and floats up, if the clearance L3 increases,
the tip 21a of the clamp arm climbs over the needle shank 15.
Therefore, the clearance L3 should be made small.
[0093] According to the sewing machine needle clamping device 1 of
the present invention, in addition to the above basic merits, the
sewing machine needle can be attached to the accommodating recessed
part only when the direction of the needle where the attaching flat
surface of the needle shank is joined to the attaching flat surface
of the accommodating recessed part is attached, and the attachment
can be performed certainly.
[0094] As it is clear from the above explanation, according to the
sewing machine needle clamping device of the present invention, the
operation which has to screw the thin sewing machine needle by the
screw to the needle clamp of small space firmly by the screwdriver
is unnecessary and the mechanism is simplified and the operation is
performed by one-touch operation of small number of times, and the
sewing machine needle such as the lock stitch sewing machine, the
serger, the double chain stitch sewing machine, or the cover stitch
sewing machine can be attached, fixed or exchanged to the needle
clamp firmly and easily, and when the clamp lever is closed, the
clamp lever is opened by the unintentional movement in the lateral
direction and the back-and-forth direction of the needle and the
malfunction that clamping of the needle is released occurs, and
this device can function as the safety device which prevents that
the sewing machine needle breaks and disperses by the collision to
other parts, and when the sewing machine needle penetrates into the
cloth that the needle is hard to pierce, in other words, when the
sewing machine needle penetrates into the cloth which has the large
friction and then the sewing machine needle come out of the cloth,
this device can prevent that the sewing machine needle slips out of
the needle clamp by the frictional force with the cloth, and when
the needle is attached to the needle clamp, the safety device which
does not drop the sewing machine needle is provided. On the other
hand, when the clamp lever is opened, the prevention to forget
clamping can be attempted because the sewing machine needle drops
from the accommodating recessed part, and the sewing machine needle
can be attached to the accommodating recessed part only when the
direction of the sewing machine needle where the attaching flat
surface off the needle shank is joined to the attaching flat
surface of the accommodating recessed part is attached, and the
attachment can be performed certainly.
INDUSTRIAL APPLICABILITY
[0095] Because the sewing machine needle is attached and fixed to
the needle clamp firmly and easily, the sewing machine needle
clamping device in the present invention can be applied suitably to
various types of the sewing machine such as the lock stitch sewing
machine, the serger, the double chain stitch sewing machine, or the
cover stitch sewing machine.
EXPLANATION OP THE NUMERALS
[0096] 1 sewing machine needle clamping device [0097] 3 sewing
machine needle [0098] 5 needle clamp [0099] 7 accommodating
recessed part [0100] 7a attaching flat surface [0101] 9 screw
[0102] 11 fixing cylindrical portion [0103] 13 attaching base
[0104] 13a attaching portion [0105] 13b elongate hole [0106] 13c
attaching portion of vertical direction [0107] 13d, 13e, 13f
surface [0108] 15 needle shank [0109] 15a attaching flat surface
[0110] 17 clamp lever abaft [0111] 19 clamp lever [0112] 21 clamp
arm [0113] 21a tip of clamp arm [0114] 21b engagement surface
[0115] 22 force acting locking part [0116] 23 needle clamp spring
[0117] 27 screw [0118] 40 hemstitch sewing machine (serger) [0119]
42 throat plate [0120] 44 looper as loop capturing device [0121] 46
lower shaft [0122] 48 letter shaft pulley [0123] 50 timing belt
[0124] 52 upper shaft pulley [0125] 54 upper shaft [0126] 56 needle
bar drive mechanism [0127] 58 needle bar [0128] 70 cam follower
[0129] 71 cam [0130] 72 lock piece [0131] 73 lock piece stopper
[0132] 74 clamp stopper [0133] 75 lock release button [0134] 76
outer shape (shank taper) [0135] 77 inner shape [0136] 78 needle
clamp forgetting prevention spring [0137] 79 D-shaped
cross-sectional shape [0138] 80 attaching hole [0139] a clamping
direction [0140] L1 straight-line distance which links central of
engagement surface of clamp arm and central point of clamp lever
shaft [0141] L2 straight-line distance which links central point of
needle shank and central point of clamp lever shaft [0142] L3
clearance between P3 and P [0143] C central point of engagement
surface of clamp arm [0144] N central point of needle [0145] P
central point of clamp lever shaft [0146] P1, P2, P3 central point
[0147] tp branch point position
* * * * *