JPS63150095A - Feed error detector of sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a feed error detection device for a sewing machine, and more specifically, it is a device for detecting a feed error in a sewing machine assembled on an assembly line. The present invention relates to a detection device capable of displaying the amount of error in feeding.

(Prior art) Conventionally, a feed adjustment mechanism for adjusting the feed difference between the front feed hoist and the rear feed hoist of a sewing machine is disclosed in, for example, Japanese Patent Laid-Open No. 59-164092.
As disclosed in the above issue, the feed adjustment screw is adjusted by rotating it with a screwdriver.

Adjustment of the sewing machine's feed distance error is carried out during the assembly line.The assembled sewing machine is driven once and a predetermined sewing pattern is trial-sewn on the test-sewing fabric. The feed error in the rear feed amount was determined visually and the adjustment screw was rotated and adjusted using a screwdriver.

(Problem to be Solved by the Invention) However, it is difficult to visually determine the amount of feed error between forward feed lifting and rear feed m based on trial sewing, and to determine the rotation M of the adjustment screw based on the determination result. This requires a great deal of skill, and the adjustment work takes a lot of time.

In addition, this adjustment work involves trial sewing using cloth, thread, and sewing machine needles, which requires a large amount of money for these materials for the adjustment work.

(Object of the Invention) The object of the present invention is to solve the above-mentioned problems, to enable even non-experts to know the feed error amount, and to accurately and reliably adjust the forward feed amount and the rear feed amount. can be done, and
It is an object of the present invention to provide a feed error detection device for a sewing machine that can reduce the cost of materials used for adjustment work.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a feed adjustment material disposed on a cloth feed dog of a sewing machine, a position detection means for detecting the position of the feed adjustment material, and a sewing machine. After driving the feed adjusting material to forward and backward feed a predetermined number of times,
Feed m error calculation means for calculating the displacement between the position before feeding and the position after the end of feeding of the feed adjustment material as an error of the feed base based on the detection signal from the position detection means; and the feed ffi error formation means The gist of the present invention is a feed error detection device for a sewing machine, which comprises a display means for displaying the amount of feed error calculated by.

(Function) When the sewing machine is driven and the feed adjustment material set on the cloth feed dog is fed forward and backward a predetermined number of times, the position detection means detects the position of the adjustment material before feeding and after the feeding ends. Detects the displacement of the position and outputs it as a detection signal.

The feed m error calculation means calculates the error in the cloth feed distance of the sewing machine based on this detection signal, and displays the feed error amount on the display means.

(Example) Hereinafter, an example embodying the present invention will be described based on the drawings.

Figures 1 and 2 show a plan view and a front view of a feed error detection device of a sewing machine, in which a large number of pole casters 2 are fixedly installed in the left and right direction on a table 1, and are placed and fixed on a conveyor table 3. This facilitates the work of transporting the sewing machine 4 to be inspected from right to left. The guide plate 5 is disposed on the rear side of the table 1 along the pole casters 2, and its left end is bent so that it can engage with a corner of the conveyance platform 3. A clamping device 6 disposed on the right front side of the table 1 clamps the corner of the conveyor table 3, and cooperates with the guide plate 5 to clamp the conveyor table 3,
That is, the sewing machine 4 is fixed to the table 1.

A control box 7 is provided on the left side of the clamping device 6,
On the top surface there is a start switch 8a and a power switch 8b.
A request lamp 8C and a display device 9 as display means are provided.

The display device 9 displays the sewing machine 4 built in the box 7.
The feed m error calculated by the arithmetic device as the feed range error calculating means for calculating the feed m error is displayed.

The feed poison detection adjustment device 10 is provided on the left side of the table 1,
The table 1 can be moved on casters 12 provided on the lower side of the base 11. A support frame 13a is mounted on the base 11.
~13c is fixed upright, and its three support frames 13a~1
The bed 4a of the sewing machine 4 is placed in the space 14 formed by the sewing machine 3c.
is inserted from the right side, and the adjustment material 15 is placed on the top surface. As shown in FIG. 5, the adjustment material 15 is formed of a rectangular film 15a made of aluminum or synthetic resin and a cloth 15b attached to the top surface of the film 15a.

A laser type discrimination sensor 16 as a position detection means is fixed to a support arm 16a fixed to the back side of a planar cross-shaped support frame 13c on the rear right side, and is attached to the rear edge of the adjustment material 15 (film 15a). is detected to detect the position of the material 15 in the front-rear direction in FIG.

Front support frame 13a and rear left side planar support frame 13
The position regulating plate 17 disposed between
Adjustment for 1j! Position i10 in the left and right direction. A proximity switch 18 is provided on the position regulation plate 17,
It turns on when the tip of the bed portion 4a comes into contact with the position regulating plate 17. A proximity switch 1 is also provided on the inner surface of the support frame 13a.
9 is provided, and when the front surface of the bed part 4a comes into contact, the switch 19 is turned on, and the adjustment machine 1 for the bed part 4a is turned on.
0 in the front-back direction.

A support plate 20 is provided on the front side of the support frame 13a, and an electromagnetic solenoid 21 is fixed at the tip of the support plate 20, and the tip side is arranged in a diagonal shape so that the actuator 21a of the solenoid 21 faces diagonally upward rearward. It forms a bend. The direction of this actuator 21a is determined when the sewing machine 4, that is, the bed 4a, is positioned with respect to the feed Q detection adjustment machine 10 (hereinafter referred to as the time when the sewing machine 4 is set).
It is arranged to face a starting switch 22 disposed on the front surface of the tip of the arm portion of the sewing machine 4. When the solenoid 21 is energized, the actuator 21a protrudes forward against the spring 23, and when the solenoid 21 is de-energized, it returns to its original position by the spring 23. Start switch 22 by
is turned on.

A pulse motor 24 is mounted on the fixed frame 2 in front of the support plate 20.
5, and a gear 26 is fixed to its drive shaft. A rotary shaft 28 is rotatably supported by a bearing frame 27 on the right side of the fixed frame 25, and a sector gear 29 fixed to the rotary shaft 28 meshes with the gear 26.

A cylindrical adjustment jig 30 is attached to the tip of the rotating shaft 28, and a protrusion 31 is formed inside the tube at the tip. This protrusion 31 is located at the fourth position when the sewing machine 4 is set.
As shown in the figure, it engages with an engagement groove 33 formed in the head of an adjustment member 32 built into the base end of the bed portion of the sewing machine 4 and used to adjust errors in the forward and backward feed amounts of the work cloth. It looks like this. The adjusting member 32 for adjusting the error in the forward feeding and backward feeding M of the work cloth is provided as a part of a known feeding mechanism for performing the forward feeding and backward feeding operations of the feed teeth of the sewing machine 4, and the adjusting member By adjusting the rotation of 32, the feed error can be adjusted. In addition, this adjustment member 3
2 and the n-feed mechanism are disclosed as well-known techniques in, for example, Japanese Patent Publication No. 164092/1983, and therefore the details thereof will be omitted. Further, the feed adjustment member 32 is normally hidden behind a cover and cannot be operated, but during inspection, the cover is removed and the adjustment operation becomes possible. The bearing frame 27 has a pair of upper and lower position detection sensors 34a.

34b and an origin sensor 34c are provided, and the sector gear 2
9 home position and maximum allowable rotation position.

The outlet 35 is installed behind the guide plate 5 of the table 1, and the plug of the sewing machine 4 is connected thereto. N arranged above and below
The G clamp 6a and the OK clamp 6b are installed on the left side of the outlet 35 and indicate whether or not the feed ω adjustment of the sewing machine 4 has been performed a predetermined number of times by lighting them.

Next, the electrical configuration of the sewing machine feed error detection device configured as described above will be explained.

In FIG. 7, a microcomputer 41 serving as a feed error calculation means is a central processing unit 42 (hereinafter referred to as CPU).
), a program memory 43 consisting of a read-only memory (ROM) storing a control program, and a CP
It is composed of a working memory 44 consisting of a readable and rewritable memory (RAM) for temporarily storing the calculation results of U42, etc. CPU42 is start switch 8
A, ON signals from the power switch 8b and the proximity switches 18 and 19 are input, and the device operates based on a control program stored in the program memory 43. The CPU 42 outputs a display control signal to the display drive circuit 46 via the input/output interface 45, and outputs a display control signal to each lamp 8.
c, 36a.

36b and controls the display device 9 to display. Also, like the CPU 42j, the interface 45
Through the motor drive circuit 47 you and the solenoid drive circuit 4
A drive control signal is output to 8 to control the drive of the pulse motor 24 and control the excitation of the electromagnetic solenoid 21.

Further, the CPU 42 receives a detection signal from the laser discrimination sensor 16 via four sensor control circuits and an interface 45, and calculates the total feed error based on the signal.

Next, the operation of the sewing machine feed error detection device configured as described above will be explained with reference to a flowchart showing the operation of the microcomputer 41.

Now, the conveyor table 3 on which the sewing machine 4 whose cloth feed amount has not been adjusted is clamped by the clamping device 6, and the sewing machine 4 is placed on the table 1.
Fix it by looking at it. Next, the feed amount detection and adjustment device 10 is moved to fit the space 14 formed by the support frames 13a to 13C into the bed 4a of the sewing machine bed 4. At this time,
The adjustment jig 3o for the feed m detection adjustment mode 1o fits into the adjustment member 32 of the sewing machine 4, and the protrusion 31 fits into the engagement groove 33.

Next, the plug of the sewing machine 4 is connected to the outlet 35 so that it can be started. The microcomputer built into the sewing machine 4 is set to a trial sewing mode for detecting the total feed difference, and when the start switch 22 is turned on, it drives and controls the feed dog and presser foot of the sewing machine 4. perform the feed operation for trial sewing. Here, in this embodiment, the pattern to be trial sewn is made by performing the forward feed operation three times, the left feed operation twice, the rear feed operation three times, and finally the right feed operation twice, that is, at the end of the trial sewing. The pattern is such that the needle drop point and the needle drop point at the start of the trial sewing match, and the front feed depth and back feed width are the same.
That is, if trial sewing is performed using a sewing machine with no total feed error, a pattern 50 shown in FIG. 8 will be formed.

Next, after placing the adjustment material 15 on the cloth feed dog of the sewing machine 4, the presser foot is lowered and the adjustment material 15 is ready for trial sewing. When setting the adjustment material 15, the laser type discrimination sensor 16 can detect the trailing edge of the adjustment material (film 15a) 15 from the start to the end of trial sewing, and the presser foot can reliably touch the cloth 15b. Set the adjustment material 15 so that it is pressed down.

After setting the adjustment materials 15, the operator returns to the control box 7.
When the power switch 8b is turned on, the CPU 42 responds to this on signal by lighting the request lamp 8C to notify the worker of a request to start work (step (hereinafter simply referred to as S) 1), and turns on the start switch 8a. Waits for operation (S2). Subsequently, when the start switch 8a is turned on, the CPU 42 judges whether the proximity switch 18, 19 is in the on state, that is, whether the sewing machine 4 is securely positioned on the feed amount detection and adjustment machine 10 (S3 ).

At this time, if the positioning has not been performed reliably, the start switch 8a will be operated again after repositioning the sewing machine 4 and adjustment 110. When the positioning is performed reliably, the CPU 42 adjusts the adjustment member 32.
Initial settings are performed (S4). This initial setting is an operation to determine the current position of the adjustment member 32, and in this embodiment, first, the sector gear 29 is rotated so that the origin sensor 34c detects a predetermined position of the sector gear 29, and then, As shown in FIG. 6, rotate the adjustment jig 30 clockwise to adjust the projection 31.
After first turning the adjustment member 32 a certain amount clockwise,
The pulse motor 24 is driven and controlled so that the adjustment jig 30 is rotated counterclockwise and the adjustment member 32 is rotated counterclockwise by a certain amount by the protrusion 31 .

This operation is performed so that the width of the protrusion 31 of the adjustment jig 3o is
Since a gap is created that is smaller than the width of the engagement groove 33, even if the protrusion 31 rotates slightly, it is absorbed by the gap and the amount of rotation is prevented from being accurately and reliably transmitted to the adjustment member 32. By once rotating clockwise and then rotating counterclockwise, the protrusion 31 brings its counterclockwise engaging portion into contact with the engaging groove 33 of the adjustment member 32. There is. Therefore, the relative positional relationship between the protrusion 31 and the engagement groove 33 is determined.

When the initial setting is completed, the CPU 42 turns off the request lamp 8C (85), and then stores the limit adjustment number N in the working memory 44 (S6).

This limit adjustment number N is determined by the sewing machine 4 with one adjustment device 10.
This is the maximum number of times that the adjustment is performed for the total feed rate, and this data is used to determine that adjustment is not possible when the total feed difference value m cannot be adjusted to a preset limit value or less even after performing this number of adjustments. . In this embodiment, the number of times N is "10".
” and the limit value M is “0.1 mm”, and these values are stored in the program memory 43 in advance,
A setting switch or the like may be provided so that the value can be changed as appropriate.

When the limit adjustment number N is stored in the working memory 44, C
The PU 42 reads out digital position data obtained by A/D converting the analog position data from the laser discrimination sensor 16 by the sensor control circuit 49 as the relative position Db of the adjustment material 15 with respect to the same sensor 16 before trial sewing, and stores the data in the work memory 44.
(S7). Once the relative position [)b is memorized,
The CPU 42 excites and controls the electromagnetic solenoid 21 to operate the actuator 21a and turn on the start switch 22 of the sewing machine 4.
is turned on (S8).

When the start switch 22 is turned on, the sewing machine 4 starts trial sewing, and the CPU 42 waits until the trial sewing of the sewing machine 4 is completed (S9). Although this determination of termination will not be described in detail, for example, it may be possible to detect the stoppage of the drive motor of the sewing machine 4, to measure the time required for trial sewing, or to detect the movement of the adjustment material 15 using a sensor such as the laser type discrimination sensor 16. This can be done by detecting when the system has stopped for a certain period of time or more.

When the trial sewing is completed, the CPU 42 calculates the relative position Da of the adjustment material 15 with respect to the sensor 16 after the trial sewing is completed, which is calculated by the laser discrimination sensor 16 and the four sensor control circuits.
is read out and stored in the working memory 44, and an error value m (=Db-Da) is calculated using the relative positions Db and Da before and after the trial sewing (SIO). That is,
If the forward feed amount and rear feed amount of the sewing machine 4 are the same, the number of forward feeds and rear feeds in trial sewing is both three times, so m=Q, and if m>O, the forward feed is the same. It can be seen that when the lift is large and, conversely, m<Q, the backward feed is large.

CPtJ42 is the absolute value 1m of the calculated feed m error value m.
511), and if the absolute value 1ml of the feed amount error value m is less than the limit value M, OK clamp 6b
turns on and waits for the next adjustment work of sewing machine 4 (812).

If the absolute value 11111 of the total feed difference value m is not less than the limit value M, the CPU 42 calculates and displays the rotation direction and amount of rotation of the adjustment member 32 in order to make the feed error value m O. The pulse motor 24 is driven to display on the device 9 and rotate the adjustment member 32 (313).

The direction of rotation is determined by the positive or negative value of the total feed difference value m, and the amount of rotation is determined based on each mechanical element of the feed mechanism connected to the adjustment member 32.

When the adjustment member 32 is rotated for adjustment, the CPU 42 subtracts "1" from the value of the limit adjustment number N in the working memory 44 (314), and determines whether the subtracted limit adjustment value N is less than or equal to rOJ. After that (S15), the trial sewing operation described above is performed again (89-510). At this time, the relative position 11Db before trial sewing is calculated as the relative position [)a after trial sewing obtained during the previous trial sewing. Then, in this trial sewing, the absolute value 1ml of the feed amount error value m is the limit value M
If the condition is below, the OK clamp 6b is turned on and the sewing machine 4 waits for the next adjustment work. On the other hand, if it is not below the limit value M, the adjustment amount of the adjustment member 32 is displayed and adjusted again. If the absolute value 1ml of the feed error value m does not become less than the limit value M even after 10 trial stitches, it is determined that the feed mechanism of the sewing machine 4 is malfunctioning and N'
Turn on the G lamp 36a to notify the operator (S16),
The adjustment of the feed error of the sewing machine 4 is completed.

In this way, in this embodiment, the adjustment interval of the adjustment member 32 based on the single feed error is displayed on the display device 9 each time trial sewing is performed, so that even non-experts can accurately and reliably perform sewing. It is possible to know the adjustment interval between the forward feed amount and the rear feed amount. Moreover, since the adjustment interval can be automatically adjusted by driving the pulse motor 24, the adjustment work can be performed very easily and accurately.

Also, the relative positions Db, [) of the adjustment material 15 before and after trial sewing.
Since a is detected by the laser discrimination sensor 16, there is no need to actually form a pattern on the cloth using a needle and thread as in the past, so the cost of materials used for adjustment work can be kept low. be able to. Moreover, since no needles are used, adjustment work can be carried out safely.

Note that this invention is not limited to the above embodiments,
For example, the adjustment member 15 used was made by pasting cloth 15b on film 15a to correspond to the actual sewing process, but the invention is not limited to this. , a resin plate, etc. may be used as the adjustment material. Further, in the above embodiment, the trailing edge of the material 15 was detected, but a block was attached to the rear side of the adjustment material 15, and the block was detected by the laser type discrimination sensor 16.
Alternatively, an optical displacement sensor may be used to detect the displacement of the block as shown in φ to detect the feed ffi+J difference, or a mark, such as a cross-shaped mark, may be placed on the adjustment material and this may be used with a COD camera, etc. It is also possible to carry out the process by using an image pickup device and processing the image using an image processing device to determine the shift of the mark and the tracking error to determine the adjustment method.

Furthermore, in the embodiment described above, the laser type discrimination sensor 16 detects the displacement of the adjustment material 15 in the front and rear direction, but a detection sensor that detects the displacement in the left and right direction is used to detect the displacement before and after trial sewing of a predetermined value or more. In some cases, the present invention may be applied to a detection adjustment device that also notifies the abnormality. Further, although the adjustment amount is displayed only on the display device, the value may also be printed on a printer.

Further, in the embodiment described above, the adjustment member 32 is adjusted by driving the pulse motor 24 in order to display the adjustment amount on the display device. Of course, it is also possible to implement the feed mother detection adjustment only for the display device 9.

(Effects of the Invention) As detailed above, according to the present invention, even an unskilled person can know the amount of feed error, and accurately and reliably adjust the forward feed and rear feed. Moreover, it has the excellent effect of keeping the cost of materials used for adjustment work low.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a feed error detection device for a sewing machine embodying the present invention, FIG. 2 is a front view, FIG. 3 is a side view of a feed 1 detection and adjustment device, and FIG. 4 is a perspective view of the sewing machine. Fig. 5 is a perspective view of the adjustment material, Fig. 6 is an explanatory diagram showing the operation of the adjustment member and the protrusion of the adjustment jig during initial setting, and Fig. 7 is an electrical diagram showing the electrical configuration of the feed error detection device. Block circuit diagram, 8th
The figure is a sewing pattern diagram for explaining the movement of the adjusting member for trial sewing, and FIG. 9 is a flowchart diagram for explaining the operation of the feed error detection device. In the figure, 1 is a table, 3 is a transport platform, 4 is a sewing machine, 4a is a bed section, 6 is a clamp device, 7 is a control box, 8a
is a start switch, 8b is a power switch, 8C is a request lamp, 9 is a display device, 10 is a feed suspension detection adjustment device, 15 is an adjustment material, 16 is a laser type discrimination sensor, 21 is an electromagnetic solenoid, 21a is an actuator, 22 is Start switch, 24 is a pulse motor, 29 is a sector gear, 30
31 is an adjustment jig, 31 is a projection, 32 is an adjustment member, 33 is an engagement groove, 41 is a microcomputer, 42 is a central processing unit (CPU), 43 is a program memory, 44 is a working memory, 46 is a display drive circuit, 47 is a motor drive circuit, 4
8 is a solenoid drive circuit, and 49 is a sensor control circuit.

Claims (1)

[Claims] 1. Feed adjustment material (1) disposed on the cloth feed dog of the sewing machine
5), a position detection means (16) for detecting the position of the feed adjustment material (15), and after driving the sewing machine to feed the feed adjustment material (15) forward and backward a predetermined number of times; , same delivery adjustment materials (
15) Position before feeding (Db) and position after finishing feeding (D
a) a feed amount error calculation means (41) that calculates the displacement (m) as a feed amount error based on the detection signal from the position detection means (16); and the feed amount error calculation means (41). A feed error detection device for a sewing machine comprising display means (9) for displaying a calculated feed error amount.