U.S. patent application number 12/694667 was filed with the patent office on 2010-07-29 for stitch quality monitoring system.
This patent application is currently assigned to GAMMILL, INC.. Invention is credited to Joseph W. Bauman, Kenneth Mark Eubanks, Matthew Paul Sherman, Paul Truman Statler, Theodore J. Stokes.
Application Number | 20100186646 12/694667 |
Document ID | / |
Family ID | 42353105 |
Filed Date | 2010-07-29 |
United States Patent
Application |
20100186646 |
Kind Code |
A1 |
Stokes; Theodore J. ; et
al. |
July 29, 2010 |
STITCH QUALITY MONITORING SYSTEM
Abstract
A stitcher is provided that includes a needle configured to
place stitches in a fabric that is moved therethrough. The stitcher
includes a sensor positioned below the fabric to monitor stitches
placed in the fabric. A microcontroller is provided configured to
receive data from the sensor and, based on such data, to compare
one or more attributes of the monitored stitches with one or more
predetermined parameters relating at least one attribute of the
fabric. The predetermined parameter may be either hardcoded inn the
microcontroller or input by a user of the stitcher prior to
beginning operation of the machine. When the attributes of the
monitored stitches fall outside of the predetermined parameters,
the microcontroller initiates notification of the user.
Inventors: |
Stokes; Theodore J.;
(Lapeer, MI) ; Sherman; Matthew Paul; (Columbia,
MO) ; Eubanks; Kenneth Mark; (Columbia, MO) ;
Statler; Paul Truman; (Columbia, MO) ; Bauman; Joseph
W.; (Cabool, MO) |
Correspondence
Address: |
HUSCH BLACKWELL SANDERS LLP
190 Carondelet Plaza, Suite 600
ST. LOUIS
MO
63105
US
|
Assignee: |
GAMMILL, INC.
Columbia
MO
|
Family ID: |
42353105 |
Appl. No.: |
12/694667 |
Filed: |
January 27, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61147517 |
Jan 27, 2009 |
|
|
|
Current U.S.
Class: |
112/470.05 ;
112/271; 112/475.17 |
Current CPC
Class: |
D05B 19/12 20130101;
D05B 69/36 20130101 |
Class at
Publication: |
112/470.05 ;
112/271; 112/475.17 |
International
Class: |
D05B 19/12 20060101
D05B019/12; D05B 69/36 20060101 D05B069/36 |
Claims
1. A monitoring system for a stitcher, said monitoring system
comprising: a sensor positioned adjacent to a workspace of the
stitcher and below a fabric positioned within said workspace, said
sensor configured to detect stitches placed in the fabric and
create images of each detected stitch as said stitcher operates; at
least one predetermined parameter relating to at least one
attribute of said detected stitches; a microcontroller in
communication with said sensor; a memory in communication with said
microcontroller, said at least one predetermined parameter being
stored in said memory; said microcontroller being configured to
receive said images from said sensor, isolate said at least one
attribute of each said detected stitch in said images, and to
compare said at least one attribute to said at least one
predetermined parameter during operation of said stitcher; means
for notification in communication with said microcontroller to
notify a user of said stitcher if said at least one attribute of
said detected stitch falls outside of said at least one
predetermined parameter.
2. The monitoring system as set forth in claim 1, wherein said
sensor is a CMOS sensor.
3. The monitoring system as set forth in claim 1, wherein said
sensor is digitally interfaced with said microcontroller.
4. The monitoring system as set forth in claim 1, wherein said
sensor is positioned to a side of said workspace and angled toward
a needle of said stitcher to detect said stitches.
5. The monitoring system as set forth in claim 1, wherein said
sensor is positioned in front of said workspace and angled toward a
needle of said stitcher to detect said stitches.
6. The monitoring system as set forth in claim 1 further comprising
a plurality of sensors configured to detect said stitches.
7. The monitoring system as set forth in claim 6, wherein said
microcontroller is configured to analyze images received from each
of said plurality of sensors and to compare said images to said at
least one predetermined parameter.
8. The monitoring system as set forth in claim 1, wherein said
predetermined parameters are hardcoded in said memory and said
memory is integral with said microcontroller.
9. The monitoring system as set forth in claim 1, wherein said
predetermined parameters are input by a user of said stitcher prior
to beginning operation of said stitcher.
10. The monitoring system as set forth in claim 1, wherein said at
least one said attribute of said detected stitches is selected from
the group consisting of a stitch length, a size of thread used to
make said stitches, stitch looping, thread bunching, stitch length,
and a distance between stitches.
11. The monitoring system as set forth in claim 1, wherein said
means for notification further comprises an audio/visual
device.
12. The monitoring system as set forth in claim 1, wherein said
microcontroller is configured to automatically stop operation of
said stitcher when said at least one attribute of said detected
stitch falls outside of said at least one predetermined
parameter.
13. A monitoring system as set forth in claim 1, further comprising
a monitor configured to display an image of each detected stitch to
a user.
14. A stitcher comprising: a needle configured to place stitches in
a fabric that is moved through said stitcher; a first sensor
positioned below said fabric to monitor said stitches while said
stitcher operates; a microcontroller in communication with said
first sensor and configured to receive data from said first sensor,
to compare at least one attribute of said monitored stitches to at
least one predetermined parameter relating to said at least one
attribute based on said data received from said first sensor, and
to determine if said at least one attribute of said monitored
stitches satisfies said at least one predetermined parameter,
wherein, when said at least one attribute of said monitored
stitches falls outside of said at least one predetermined
parameter, a user of said stitcher is notified while said stitcher
is in operation.
15. The stitcher as set forth in claim 14, wherein said stitcher is
one of a long-arm stitcher and a standard sewing machine.
16. The stitcher as set forth in claim 14, wherein said at least
one attribute is selected from the group consisting of a stitch
length, a size of thread used to make said stitches, stitch
looping, thread bunching, stitch length, and a distance between
stitches.
17. The stitcher as set forth in claim 14, further comprising at
least a second sensor positioned below said fabric and also in
communication with said microcontroller, wherein said
microcontroller is configure to receive data from said second
sensor and to compare said at least one attribute of said monitored
stitches to said at least one predetermined parameter based on said
data received from said second sensor.
18. A method of operating a stitcher, said method comprising:
positioning a sensor below a fabric moved through said stitcher;
monitoring, with said sensor, stitches placed in said fabric by
said needle; communicating data relating to at least one attribute
of said monitored stitches from said sensor to a microcontroller in
communication with said sensor; comparing, in said microcontroller,
said at least one attribute of said monitored stitches with at
least one predetermined parameter relating to said at least one
attribute during operation of said stitcher; and notifying a user
of said stitcher is said at least one attribute of said monitored
stitches falls outside of said set of predetermined parameters.
19. The method as set forth in claim 19, wherein the step of
comparing said at least attribute of said monitored stitches with
said at least one predetermined parameter further comprises
comparing at least one attribute selected from the group consisting
of a stitch length, a size of thread used to make said stitches,
stitch looping, thread bunching, stitch length, and a distance
between stitches.
Description
CROSS REFERENCE
[0001] This application claims the priority of provisional
application Ser. No. 61/147,517, filed Jan. 27, 2009.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to long-arm stitchers and,
more particularly, to a stitch quality monitoring system for
long-arm stitchers.
[0004] 2. Related Art
[0005] Conventional long-arm sewing machines are generally used for
quilting and/or sewing fabrics that are not easily moved through a
sewing machine. In particular, quilts generally include two outer
layers and a filler material that is sewn between the outer layers.
Accordingly, to limit the amount of fabric movement when quilting,
long-arm sewing machines are typically mounted on a pair of rails
that allow the operator to move the needle of the machine while
keeping the quilt stationary.
[0006] However, the fabric thickness can cause the fabric to bunch
during movement of the needle and/or may cause erratic feeding of
the fabric through the needle. Moreover, the filler being stitched
into the quilt is often uneven, thereby adding to sewing
difficulties and creating difficultly for the operator to follow a
stitching pattern, especially when the pattern is not straight. As
such, the stitching in the quilt may become uneven and/or may have
variable stitch lengths. Additionally, the sewing thread may break
and/or loop undesirably when the speed of the machine is
adjusted.
[0007] Typically, stitch quality is monitored visually by the
operator of the machine. For example, U.S. Pat. 6,260,495, issued
to Stewart, describes a monitoring system for a sewing machine that
includes a camera to provide images of the article being sewn on a
monitor. The image is held for approximately two or three seconds
while a worker visually inspects a quality of the hem. In the event
the worker sees a hem that is defective, the worker can hit an
on/off switch to stop the sewing machine. Unfortunately, such
monitoring systems are subject to human error and can often allow
undesirable stitching to go undetected and/or slow the sewing
process.
[0008] As such, it is desirable to have a sewing machine capable of
monitoring and analyzing the stitching in a quilt as the quilt is
assembled.
SUMMARY OF THE INVENTION
[0009] A stitcher is provided for placing stitches in a fabric. The
stitcher includes a monitoring system having at least one sensor
positioned below the fabric and angled toward a needle of the
stitcher to monitor the stitches placed in the fabric. A
microcontroller communicates with the sensor and is programmed with
software that analyzes images of the stitches acquired by the
sensor. The images are compared with a predetermined set of
parameters stored in a memory associated with the microcontroller.
These parameters may be either hardcoded in the memory and/or input
by a user of the stitcher. When the attributes of the monitored
stitches fall outside of the predetermined set of parameters, the
stitcher is stopped. The microcontroller then notifies the user as
to which parameter has not been met by the stitches. In one
embodiment, a monitor is provided to display images of the stitches
for manual stitch analysis and/or to display the parameters that
have been violated by the stitches.
[0010] The stitcher may be a long-arm stitcher or a standard sewing
machine that is configured for either commercial or household use.
In the exemplary embodiment, the attributes of the stitches that
are analyzed include any one of stitch looping, thread bunching,
stitch length, and/or a distance between stitches. The system may
also be configured to notify the user if no stitch is detected.
[0011] These aspects are merely illustrative of the innumerable
aspects associated with the present invention and should not be
deemed as limiting in any manner. These and other aspects, features
and advantages of the present invention will become apparent from
the following detailed description when taken in conjunction with
the referenced drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Reference is now made more particularly to the drawings,
which illustrate the best presently known mode of carrying out the
invention and wherein similar reference characters indicate the
same parts throughout the views.
[0013] FIG. 1 is a perspective view of a standard long-arm
stitcher.
[0014] FIG. 2 is a schematic view of a monitoring system that may
be used with the long-arm stitcher shown in FIG. 1.
[0015] FIG. 3 is a schematic view of the monitoring system shown in
FIG. 2 in use with the stitcher shown in FIG. 1.
[0016] FIG. 4 is an algorithm of a monitoring process performed by
the monitoring system shown in FIG. 2 to analyze a quality of
stitches created by the stitcher shown in FIG. 1.
[0017] FIG. 5 is an algorithm of image processing performed by the
monitoring system shown in FIG. 2 to acquire images of the stitches
created by the stitcher shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] In the following detailed description numerous specific
details are set forth in order to provide a thorough understanding
of the invention. However, it will be understood by those skilled
in the art that the present invention may be practiced without
these specific details. For example, the invention is not limited
in scope to the particular type of industry application depicted in
the figures. In other instances, well-known methods, procedures,
and components have not been described in detail so as not to
obscure the present invention.
[0019] FIG. 1 illustrates a standard long-arm stitcher 10 including
a base 12, an arm 14, and a take up lever box 16. Although the
present invention is described with respect to a long-arm stitcher,
one of ordinary skill in the art would recognize that the present
invention is also applicable to standard sewing machines. Moreover,
the present invention is capable of operating with both commercial
and household long-arm stitchers and sewing machines. The arm 14 is
coupled to the base 12 at a back end 18 of the stitcher 10. A first
portion 20 of the arm 14 extends upward from the base 12, and a
second portion 22 of the arm 14 extends from the first portion 20
substantially parallel to the base 12. The take up lever box 16 is
disposed on the arm 14 at a stitching end 24 of the stitcher 10
that is opposite the back end 18. The stitching end 24 of the
stitcher 10 forms a workspace 26 where a fabric is stitched by an
operator of the stitcher 10. The stitching end includes a needle
bar 28 having a needle 30 inserted therein and a hopping foot 32
each extending downward toward a needle plate 34 disposed on the
base 12. The needle plate 34 is attached to a square throat plate
36. The throat plate 36 is configured to be removed to provide
access to a rotary hook assembly (not shown) positioned within the
base 12 below the throat plate 36.
[0020] During operation, the needle bar 28 moves up and down
thereby moving the needle 30 to form a stitch in the fabric. The
needle bar 28 can be adjusted up or down to provide a proper
machine timing height. A small hole in the needle plate 34
restricts movement of the thread as the stitch is formed. The
hopping foot 32 raises and lowers with the movement of the needle
30 to press and release the fabric as the stitch is formed. The
hopping foot 32 is designed to be used with rulers and templates
and has a height that can be adjusted for proper stitch formation.
A control box 48 is provided to control the operation of the
stitcher 10.
[0021] FIGS. 2 and 3 illustrate a monitoring system 38 used with
the stitcher 10 shown in FIG. 1 to monitoring a stitch quality
during operation of the stitcher 10. Specifically, the monitoring
system 38 is configured to detect and monitor stitches placed in
the fabric as it is moved through the stitcher 10. The monitoring
system 38 includes a sensor or camera 40 configured to be
positioned adjacent the workspace 26 of the stitcher and below the
fabric. In the exemplary embodiment, the sensor 40 is a
complementary metal-oxide-semiconductor (CMOS) sensor that provides
images of the stitches placed in the fabric as the fabric moves
through the stitcher 10. As is well known in the digital arts, CMOS
sensors accomplish the task of capturing light and converting it
into electrical signals. A CMOS chip is a type of active pixel
sensor made using the CMOS semiconductor process. Extra circuitry
next to each photo sensor converts the light energy to a voltage.
Additional circuitry on the chip may be included to convert the
voltage to digital data. More specifically, the CMOS sensor as
utilized in an embodiment of the disclosed monitoring system
accumulates a signal charge in each pixel proportional to a local
illumination intensity, serving a spatial sampling function. When
exposure is complete, a charge-to-voltage conversion takes place in
each pixel to create an image.
[0022] In another embodiment, the sensor 40 is any sensor or camera
capable of detecting and monitoring the stitches as described
herein, for example a charge-coupled device (CCD) sensor. A CCD is
an analog device. When light strikes the chip it is held as a small
electrical charge in each photo sensor. The charges are converted
to voltage one pixel at a time as they are read from the chip.
Additional circuitry in the camera converts the voltage into
digital information. In short, a CCD sensor transfers each pixel's
charge packet sequentially to a common output structure, which
converts the charge to a voltage, buffers it and sends it off-chip
as an image.
[0023] In the embodiment shown in FIG. 3, three sensors 40 are
positioned adjacent to the workspace 26. Specifically, a first
sensor 40a is positioned in front 42 of the workspace 26, and a
pair of second sensors 40b are positioned on each side 44 of the
workspace 26. Each sensor 40 is angled toward the needle 30 of the
stitcher 10. In an alternative embodiment, the monitoring system 38
includes only sensor 40a positioned in front 42 of the workspace 26
and angled toward the needle 30. In another embodiment, the
monitoring system 38 only includes sensors 40b positioned on each
side 44 of the workspace 26. In yet another embodiment, the
monitoring system 38 includes only one of the pair of sensors 40b.
In each embodiment, the sensors 40 are angled toward the needle 30
of the stitcher 10. The sensor 40 is configured to acquire images
of the fabric and stitches as the stitches are placed in the
fabric. These images are then transmitted to a microcontroller 46
in communication with the sensor 40.
[0024] The microcontroller 46 may be disposed adjacent to the
stitcher 10 and, in the exemplary embodiment, is digitally
interfaced with the sensor 40 and electronically coupled to the
control box 48. In alternative embodiments, the microcontroller 46
may be physically coupled to the stitcher 10 or positioned remotely
from the stitcher 10 and coupled to the sensor 40 and control box
48 in a wired or wireless manner. The microcontroller 46 is
configured to analyze attributes of the stitches detected by the
sensor 40 to determine if the attributes fall within a set of
predetermined parameters that are defined for the stitches.
Specifically, the microcontroller 46 includes a processor 50
programmed with software that analyzes images of the stitches taken
by the sensor 40 to compare the attributes of the detected stitches
with the predetermined set of parameters. In an embodiment
including more than one sensor, the images from each sensor may be
combined prior to analysis or each image may be individually
analyzed. In the exemplary embodiment, the processor 50 is
programmed with American National Standards Institute (ANSI) C
software; however, as will be appreciated by one of ordinary skill
in the art, the processor may be programmed with any software
capable of analyzing the image as described herein.
[0025] In the exemplary embodiment, the attributes analyzed by the
microcontroller 46 include the stitch looping and stitch bunching.
For example, the microcontroller 46 determines if the stitch
looping includes a predetermined amount of thread and/or a
predetermined tightness and if a correct amount of thread is being
run through the needle. In other embodiments, the microcontroller
46 can be programmed to determine if there is no stitch present in
the fabric or if the stitch length and distance between the
stitches falls within predetermined parameters. The predetermined
parameters are hardcoded in the processor 50 based on a desired
stitch length and/or thread size. Alternatively, the predetermined
parameters may be programmed by a user prior to operation of the
stitcher 10. Accordingly, the monitoring system 38 allows for
automatic detection of the stitches without user intervention.
Further, the monitoring system 38 may be customized based on the
stitch length and thread size. In the exemplary embodiment, the
microcontroller 46 has the ability to save features embedded in the
video in non-volatile and/or volatile memory that is used to
compare the current stitch with the predetermined parameters for
the purpose of "GOOD/BAD" stitch detection. Specifically the
features of the stitch are seen as point to point lines of constant
contrast in a video array output. This point to point line is
analyzed to determine if the stitch is good or bad. For example,
the criteria for "GOOD/BAD" may be the detection of the presence or
absence of a loop from point to point. If the point to point line
is straight, no loop is present and the stitch is flagged as
"GOOD". If the point to point line is not straight and loops from
point to point, the stitch is flagged as "BAD".
[0026] The algorithms shown in FIGS. 4 and 5 illustrate the steps
taken by the monitoring system 38 during operation of the stitcher
10. As the fabric is run through the stitcher 10, the
microcontroller 46 automatically analyzes each stitch placed in the
fabric. Specifically, at step 100 an image of each stitch is taken
by the sensor 40 as the fabric passes through the workspace 26. The
image is then processed at step 102 following the algorithm set
forth in FIG. 5. At step 104, the microprocessor 46 determines
whether the stitch quality falls within the predetermined
parameters. If the stitch quality falls within the predetermined
parameters 106, the microcontroller begins analyzing the next
stitch. If the stitch quality falls outside of the predetermined
parameters 108, a user warning is initiated 110. In one embodiment,
the stitcher 10 is stopped and a notification is sent to the user
via a monitor 52. The notification includes an analysis of what
parameters have been violated by the stitch. The user is then able
to adjust the stitcher 10 accordingly to correct the errors in
stitching. When the error is corrected, the stitcher 10 is
restarted and the microcontroller 46 continues to analyze each
stitch. In the exemplary embodiment, the notification displays a
description of each parameter violated on the monitor 52.
Alternatively, the notification may be an alarm, a light, and/or
any other audio/visual notification. Further, in an alternative
embodiment, the user can manually inspect the stitching on the
monitor 52 to determine which parameters have been violated. In one
embodiment, the user manually stops the stitcher 10 using a switch
54. Although, the monitor 52 and the switch 54 are illustrated as
being integral with the monitoring system 38, as will be
appreciated by one of ordinary skill in the art, these features may
be separate from and electronically coupled to the monitoring
system 38.
[0027] FIG. 5 illustrates an algorithm of the image processing step
102. Upon initiation of the image processing step 102, color
separation 112 is performed to maximize the contrast between the
fabric and the thread. Next, the microprocessor 46 detects 114
loops in the stitch by analyzing the thread line. Specifically,
loops in the stitch are detected 114 as curves rather than straight
lines which indicate a proper stitch. If a loop is detected 116, a
poor quality flag is set 118 to initiate 110 the user warning. If a
loop is not detected 120, the poor quality flag is cleared 122 and
the microprocessor 46 begins analyzing the next stitch 124.
Although the algorithm shown in FIG. 5 is described with respect to
determining loops in the stitch, as will be appreciated by one of
skill in the art, the same algorithm is also used to monitor each
of the predetermined parameters being analyzed by the
microprocessor 46.
[0028] Accordingly, the present invention provides real-time
analysis of stitches placed in a fabric by notifying a user of the
stitcher 10 when a stitch quality falls outside of predetermined
parameters. As such, the present invention provides a more cost
efficient means of correcting stitch errors, thereby reducing costs
associated with wasting or re-stitching incorrectly prepared
fabrics.
[0029] As various modifications could be made to the exemplary
embodiments, as described above with reference to the corresponding
illustrations, without departing from the scope of the invention,
it is intended that all matter contained in the foregoing
description and shown in the accompanying drawings shall be
interpreted as illustrative rather than limiting. Thus, the breadth
and scope of the present invention should not be limited by any of
the above-described exemplary embodiments, but should be defined
only in accordance with the following claims appended hereto and
their equivalents.
* * * * *