JPS62213790A - Sewing machine equipped with tape feeder - 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] [Industrial application field]

The present invention relates to a sewing machine having a tape sewing function.

[Prior art]

Conventionally, sewing machines with tape stitching functions include those that control the tape feed at a predetermined ratio of the feed speed of the work cloth (Japanese Patent Laid-Open No. 175586/1986), and those that control the tape tension using a strain gauge. There is a known method (British Patent Publication No. GBA2152016) in which the tension of the tape is measured and the tension of the tape is controlled so that the measured value becomes equal to a set target value. In such a device, the speed ratio and tape tension to be controlled are set to predetermined discrete values by a switch. Then, during sewing, the operator operates a switch to change the speed ratio and tape tension.

[Problems to be solved by the invention]

Tape sewing machines utilize the elasticity of tape to
It is used to add gathers to products. The degree of gather required for a product is not always constant and may vary depending on the position even in one continuous sewing path. In this way, when creating different degrees of gathers depending on the sewing location, the operator must stop needle movement at a predetermined position, operate the switch mentioned above to change the state of tape elongation, and then continue sewing. was there. For this reason, the position at which the degree of gathering changes depends on the intuition of the operator, which impairs the uniformity of the product. In particular, when the degree of gathers in the sewing route appears symmetrical to other routes, it is difficult to achieve a symmetrical finish. Furthermore, since it is necessary to interrupt sewing and operate a switch, there is a problem in that work efficiency is poor.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to automate tape sewing control by programming control data, and in particular, to automate tape sewing control by programming control data. When the pattern appears symmetrical to the sewing path, symmetrical sewing is automatically performed using the control data of other sewing paths without inputting the control data of that path.
The purpose is to simplify data input and improve sewing efficiency.

[Means to solve the problem]

The structure of the invention for solving the above problems is as follows. That is, the present invention includes a sewing length detector that detects a value related to the length sewn by a sewing machine needle, and a device that variably applies tension to a tape that is supplied between a presser foot and a feed dog and is sewn onto a workpiece cloth. a detector for detecting a physical quantity related to the tension of the tape; a data input means for variably inputting a value related to the tension that is a control target for the tape; and the data input means a control device that outputs a signal for controlling the state of the tape to the tension applying means so that the set control target value becomes equal to the measured value detected by the tension detector; The data input means has means for inputting a value related to the sewing length and a value related to the tension of the tape for each section divided into a plurality of sections in one sewing route, and the control device , a sewing position detection section that receives a signal from the sewing length detector to detect the current sewing section; and a sewing position detection section that detects the current sewing section by inputting a signal from the sewing length detector; a tension control section that sequentially controls the tension applying means so that the tape is in a specified state until the sewing of the specified sewing length is completed, and one sewing path is symmetrical with the other sewing paths. When present, the present invention is characterized by having a symmetrical sewing control section that controls sewing on that sewing path in a symmetrical sewing order based on data on other sewing paths. In the above, the value related to the tape tension refers to the tape tension and the elongation rate of the tape, etc., and the physical quantity related to the tape tension refers to the value that is used to directly or indirectly measure the tension, elongation rate, etc. refers to the corresponding physical variable that is detected. Therefore, when the control device controls the state of the tape so that the measured value becomes the control target value,
The two variables being compared can be any variable that correlates with tape tension. In particular, the sewing length of the workpiece fabric for each sewing section and the length of the tape to be sewn in that section (value in a non-stretched state) are entered as input data, and from these values the tape for realizing the sewing is determined. It is desirable to calculate the tension of , and then control the actual tape tension to reach this value. In such a case, since the sewing length and tape length are input, data creation is easy and the finished dimensions of the product can be easily predicted.

[Effect]

The data input means inputs, for each section divided along the sewing path, a value related to the sewing length and a value related to the length of the tape sewn to that section as tape feeding control data. At this time, when one sewing route appears symmetrically with other sewing routes, only data (route pattern number, etc.) specifying the basic route that is symmetrical to it is input without inputting control data. The control device determines the current sewing section based on the signal from the sewing length detector and, based on the control data, specifies the tape for each divided section until sewing of the designated sewing length is completed. The state! s (tension, elongation, etc.). Then, when the path is symmetrical, tape sewing is controlled using the control data of the basic path in reverse order. By such action, the state of the tape is automatically changed with respect to the sewing position in accordance with the programmed control data. As a result, gathers of a predetermined degree can be automatically placed at a predetermined programmed position, and the tape can be easily sewn along a symmetrical path.

【Example】

The present invention will be described below based on specific examples. FIG. 1 is a perspective view showing the overall configuration of a sewing machine equipped with the apparatus of this embodiment. An arm 3 is protruded from the sewing machine frame 1, and a needle 6 is attached to the table 2.
It is arranged so that it can move up and down. A support arm 4 is pivotally supported on the lower side of the arm 3, and a presser foot 5 is fixed to the tip of the support arm 4. The presser foot 5 controls the feed of the workpiece cloth 8 by acting together with a feed dog (path shown) disposed below. The motor fixing base 9 is fixed to the upper part of the sewing machine frame 1, and a motor 20 is disposed thereon. The tension applying means mainly includes a motor 20, a driving roller 21, a driven roller 22, a tension lever 32, and a coil spring 33. Drive roller 21 is operatively coupled to motor 20 via a drive shaft 25 and gears. The driven roller 22 is in contact with the drive roller 21 and is supported by a bearing 23 so as to rotate in the opposite direction as the drive roller 21 rotates. The tension lever 32 is rotatably supported by a support member 34 provided on the arm 3. A coil spring 3 is attached to one end of the tension lever 32.
3 is engaged, which biases the tension lever 32 to rotate in six directions. The tape 7 is wound around a bobbin 12, which is supported by a support 11 fixed to a motor fixing base 9. The tape 7 is unwound from the bobbin 12, is sandwiched between the driven roller 22 and the driving roller 21, is wound half a turn around each of them, descends along the front surface of the arm 3, and is passed between the driven roller 22 and the driving roller 31. It is engaged and reaches the presser foot 5. Tension is applied to the tape 7 by a tension roller 31. The tension lever 32 stops at a position where it generates a rotating force that balances the tension of the tape 7. The more it rotates in the opposite direction, the greater the tension applied to the tape 7. The tape 7 is moved forward and backward as the drive roller 21 rotates forward and backward. An angle detector 40 consisting of a potentiometer is used to detect the rotation angle θ of the tension lever 320.
is provided, and its output signal is sent to an A/D converter 58.
It is input to the control device 50 via. Since the rotation angle θ of the tension lever 32 is proportional to the tension of the tape, the current tension of the tape 7 can be measured from this signal, and the motor is adjusted so that the tension lever 32 stops at the commanded angle. By controlling the rotation of 20, the desired tension can be obtained. FIG. 2 is a block diagram showing the electrical configuration of the tape feeding device according to the embodiment. The data input means consists of a dial gauge 57 for manually setting the tension or elongation rate, a keyboard 56 for inputting programmed data regarding the elongation rate of the tape together with the sewing length, and a CRT display 59 for displaying input data. . The control device 50 is composed of a computer system, which includes a central processing unit (CPU) 51, a ROM 52 that stores a control program, and a constant of proportionality of the rotation angle of the tension lever 32 to the elongation rate of the tape. It is composed of a RAM 53 that stores programmed control data for each type of tape feeding, an input/output port 54, and a motor drive circuit 55. RAM53
is backed up by a battery (not shown). The motor 20 is a pulse motor, and the motor drive circuit 55 is a pulse generator that receives rotation command pulses from the CPU 51 and generates multiphase excitation pulses. Reference numeral 60 denotes a counting detector, which is composed of an encoder that detects the number of rotations of a main shaft that controls the vertical movement of the needle of the sewing machine, and a counter that counts its output signal. 64 is a sewing machine motor and drive device 62
Driven by. Next, the operation of the device of this embodiment will be explained based on a flowchart showing the processing procedure of CPtJ51. (a) Measuring the feed pitch of the work cloth After setting the feed pitch during sewing, test-sew a cloth of a certain length d, and calculate the number of stitches t from the increase in the output data of the stitch count detector at that time.
is detected, and the pitch P is calculated by dividing the length d by the number of stitches t,
It is stored in RAM53. (b) Measurement of elongation characteristics of the tape with respect to the rotation angle of the tension lever. First, as shown in FIG. 3, a signal is input from the angle detector 40, and the tension lever 320 times e angle θ is the angle θ at which the tension applied to the tape 7 is zero. The motor 20 is controlled so that (200 to 208
). Here, the rotation angle θ is an angle taken in the direction from the vertical direction. Next, the drive roller 21 is rotated by a predetermined angle α, the tape is wound by Rα (a value converted to an elongation rate of 0, R is the radius of the roller), and the rotation angle β of the tension lever 320 at that time is detected as an angle. input from the device 40 (2
10-212). Next, the proportionality constant of the rotation angle θ to the elongation rate X of the tape is calculated using the following equation. However, f(θ) is the path length from the drive roller 21 to the presser foot 5 at the rotation angle θ. Once the proportionality constant is determined in this way, the relationship between the rotation angle θ and the elongation rate X can be determined using the following equation. θ=θ. -A-x...(2
) (c) Control data input In Figure 4, the data input program is step 1.
08 and below. An input screen is displayed on the CRT display 59 as shown in FIG. 7, and data is sequentially input into predetermined positions. Sewing length L of the second section
When (D) is input, the number of stitches K (D) corresponding to the sewing length is obtained by dividing that value by the feed pitch P (11
4-116). Next is the tape length of the third section! (D) is input, and the elongation rate Xi (D) is calculated from this value. Furthermore, the tension lever 320 achieves that elongation rate.
The control target angle θs (D) is calculated using the following equation. θs (D)=θ0-A-XS(D)-(4)
In this way, data for all sewing sections are input and one sewing path (
pattern) control data is completed. When tape sewing the work cloth shown in Fig. 10, the sewing path N
α1 and Nα2 appear symmetrically with respect to glaze O. That is, since the sewing machine has a wide space on the left side of the table relative to the needle, the unsewn portion of the work cloth is placed on the left side and sewn. Therefore, in each route, sewing progresses from eight points in the same arrow direction (clockwise). At this time, the tape state changes in the order of A→B-C on the path Nα1, and changes in the order of C→B-A on the path Nα2. In such a case, there is no need to input the control data for route Nα2, and it is only necessary to input the pattern number (1 in this case) of the reference route with route Nα1 as the reference route (1
10). When the number is input, the control data for the route Nα2 is created by reversing the order of the control data for the reference route (112). The control data input and created in this way is stored in the RAM 53 in the relationship shown in FIG. (d) A manufacturing process In FIG. 5, a sewing path pattern is selected from the keyboard 56 in the sewing order of one product, and the corresponding control data is transferred to a predetermined area of the RAM 530. Thereafter, the steps from step 306 onward are executed, and the sewing process for one product is executed. Here, C is the pattern number of the sewing route. W is a pointer indicating the start address of the RAM where the c-th pattern is stored. Next, the sewing process for each section is executed in step 310. As shown in FIG. 6, when the tension lever 32 is set to the initial value θs (1) at step 4°O and the start SW is pressed, steps 404 and subsequent steps are executed. The data from the stitch number detector 60 is input. After the stitch number counter NC is reset and the section number is set to 1 (404 to 406), the sewing process of the second section from step 408 onwards is executed. . After the tension lever 32 is set to the control target angle θ, (D), when the drive pedal or motor start switch 565 of the sewing machine is turned on, a signal for driving the sewing machine motor 64 is output (408-
412). Next, steps 408 to 412 are executed until the count NC detected by the stitch count detector 60 becomes equal to the commanded stitch count K(D) in that section, and the tension lever 32 is controlled to the control target angle. Therefore, the elongation rate of the tape is controlled to the control target value, and sewing progresses. Next, when the sewing of the first section is completed, the vertical movement of the sewing machine needle is temporarily stopped, and it is determined whether the sewing of the entire section has been completed.If the sewing is not completed, the sewing process of the next section is executed. , the process returns to step 408 and the above processing is executed. In the above, the angle control of the tension lever is performed as follows. In FIG. 9, the output data of the angle detector 40 is input as θ (510). The measured value θ of the rotation angle is the control target angle θ. CD), and the control target angle θS (D) is compared with the measured value θ
When the actual tape elongation rate is larger than the target value by Δ, the motor 20 is rotated forward by a predetermined amount and the tape elongation rate is controlled to be smaller (51
2-514). On the other hand, the measured value θ is the control target angle θS (
When Δ is larger than D), the actual tape elongation rate is too small compared to the target value, so the motor 20 is reversed by a predetermined amount and the tape elongation rate is controlled to increase (516 to 518). . The above series of processes is repeatedly executed in real time, and eventually the rotation angle θ of the tension lever 320 is controlled within a range of ±Δ with respect to the control target angle θs (D). As a result, the elongation rate of the tape is also controlled within a predetermined range with respect to the control target value XS. In this way, the tape is accurately controlled to the programmed target elongation rate both during sewing and when the sewing machine is stopped. Therefore, the tape can be sewn onto the workpiece cloth at the set elongation rate from the first stitch at a desired position. In this embodiment, since the sewing length and tape length are input as control data, there is an advantage that data can be easily created from the finished dimensions and the gather pattern. [Modification] In the above embodiment, the control data for the symmetrical route is automatically created from the control data for the reference route. However, if only the control data for the reference route is stored, the symmetrical In the case of a route, the control data for the reference route may be taken out in reverse order and controlled. Since the light transmittance of the tape changes depending on the elongation rate of the tape, the elongation rate of the tape can be directly measured by measuring the transmittance. Therefore, by comparing the measured value and the control target value, it is also possible to control the elongation state of the tape. Instead of the elongation rate of the tape, the tension of the tape may be given for each sewing section as the control data. In such a case, the measured value of tension from the angle detector and the control target value of tension are directly compared, regardless of the type of tape, and the tension of the tape is controlled by the same process as in the above embodiment. be exposed. In addition, when setting the elongation rate, in the above embodiment, the control target value was converted from the elongation rate to the rotation angle of the tension lever.
Convert the measured value of the angle detector to the elongation rate using the formula ■),
This value may be compared with the growth rate of the control target value.

【Effect of the invention】

The present invention provides a sewing machine having a tape sewing function that can control the state of tape tension, elongation rate, etc., by inputting control target values such as tape tension, elongation rate, etc. into a program in relation to the sewing position. Control data. The tape is sewn onto the fabric to be processed while automatically controlling the state of the tape based on The feature is that tape stitching is performed. Therefore, the input of control data is simplified, and even if the degree of gathers changes partially, all products can be automatically and uniformly sewn, improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a sewing machine having a tape feeding function according to a specific embodiment of the present invention, FIG. 2 is a block diagram showing the electrical configuration of the tape feeding function section, and FIG.
Figures 4, 5, and 6 are flowcharts showing the processing procedure of the computer system used in the sewing machine, Figure 7 is an explanatory diagram showing the data input screen, and Figure 8 is an explanatory diagram showing the data input screen. An explanatory diagram showing the structure of control data, FIG. 9 is a flowchart showing the control procedure of the tension lever,
FIG. 10 is an explanatory diagram showing a symmetrical sewing path. 1... Sewing machine frame 2... Table 3.
... Arm 5 ... - Presser foot 7 ... Tape 8 ... Work cloth 12 ... Bobbin 20 ... - Motor 21 ... Drive roller 22°゛ Follower roller 32
・°゛°°Tension lever 31・-Tension roller 40°...Angle detector patent applicant Brother Industries, Ltd. Agent Patent attorney Osamu Fujitani Figure 5 Atsushi Figure 6

Claims (5)

[Claims] (1) A sewing length detector that detects a value related to the length sewn by a sewing machine needle, and a device that variably applies tension to the tape that is supplied between the presser foot and the feed dog and is sewn onto the workpiece fabric. a tension applying means; a detector for detecting a physical quantity related to the tension of the tape; a data input means for variably inputting a value related to the tension that is a control target for the tape; and a setting by the data input means. a control device that outputs a signal for controlling the state of the tape to the tension applying means so that the control target value detected by the tension detector becomes equal to the measured value detected by the tension detector; The means includes means for inputting a value related to the sewing length and a value related to the tension of the tape for each section divided into a plurality of sections in one sewing path, and the control device is configured to input a value related to the tension of the tape. a sewing position detection section that receives a signal from a length detector to detect the current sewing section; and a sewing position detection section that detects the current sewing section by inputting a signal from the length detector; a tension control section that sequentially controls the tension applying means so that the tape is in a specified state until sewing of the long length is completed; What is claimed is: 1. A sewing machine equipped with a tape feeding device, comprising: a symmetrical sewing control section that controls sewing on the sewing path in a symmetrical sewing order based on data on other sewing paths. (2) The tape feeding device according to claim 1, wherein the data input means includes elongation rate input means for inputting the elongation rate of the tape for each section as a value related to the tension. Sewing machine equipped with. (3) The tape feeding device according to claim 2, wherein the input means includes a conversion means for converting the elongation inputted by the elongation input means into a corresponding tape tension. Sewing machine equipped with. (4) The tape feeding device according to claim 2, wherein the elongation rate input means is a data input means for inputting a sewing length of the work cloth and a tape length corresponding thereto. sewing machine. (5) The tape feeding device according to claim 1, wherein the detector is a transmittance measuring device that measures the elongation rate of the tape by measuring the light transmittance of the tape. Sewing machine equipped with.