JP4839831B2 - sewing machine - Google Patents

Description

  The present invention relates to a sewing machine, in which an operator can easily understand the rotation direction of a main shaft (the direction of rotation of a hand pulley) for moving a needle bar other than the needle upper position to the needle upper position along the shortest path at the start of sewing. It's about what I'm trying to inform

  Conventionally, as a sewing machine, for example, in a dovetail hole sewing machine having a needle bar or a looper, when an eyelet stitching seam is sewn on a work cloth by a stitch pattern for a dovetail hole stitching selected in advance, at the end of sewing, The needle bar stops at the needle upper position immediately before the sewing position for the outer needle, that is, the inner needle upper position. However, for example, when the pattern confirmation mode is set, it is possible to confirm the eyelet stitching stitch to be sewn next by moving only the feed base without moving the needle bar up and down.

  In this case, the operator manually operates the hand pulley to make it easy to check the stitch pattern, and with the needle bar lowered to a position where the lower end of the sewing needle approaches the work cloth on the feed base, The stitch pattern is often checked. Thus, in this state where the needle bar is lowered from the needle up position, when performing the next sewing, the needle up position error state occurs and sewing cannot be performed. Therefore, the operator manually operates the hand pulley again to move the needle bar to the needle upper position before starting sewing.

  Therefore, for example, the sewing machine described in Patent Document 1 is provided with a sewing machine motor for driving the main shaft and a hook driving motor for driving the half-rotating hook, respectively, so that when the power is turned on, the origin position setting of the main shaft and the hook shaft origin are performed. When performing the setting, first, the sewing machine motor is driven to automatically move the needle bar to the needle upper position so that the sewing needle and the half-turn hook do not interfere with each other.

JP-A-10-328454 (pages 4-5, FIG. 9)

  In the sewing machine described in Patent Document 1, when the power is turned on, the needle bar is automatically moved to the needle up position. For this purpose, the ROM of the control device reads “To top dead center of needle bar”. If the needle bar is in a position other than the top dead center when sewing is started and the cost is increased, the needle bar is raised. There are problems such as being unable to move to the dead center.

  However, when the operator rotates the hand pulley manually to move the needle bar to the needle upper position without providing a control program for “retracting the needle bar to the top dead center”, We do not know which direction to rotate or counterclockwise. Therefore, it is only necessary to first rotate the hand pulley in any direction and the needle bar should be raised. However, when it is lowered, the hand pulley will be rotated in the opposite direction, and the "needle up position error" is canceled. There are problems such as complicated operations and delayed start of sewing.

  The present invention has been made to solve the above-described problems. At the start of sewing, the needle bar is manually moved to the needle up position to cancel the “needle up position error”. The object is to enable speeding up and simplification.

The sewing machine according to claim 1 captures a thread ring that supplements a thread ring of an upper thread in cooperation with a needle bar that is reciprocated up and down via a main shaft by a sewing machine motor and a sewing needle that is attached to the lower end of the needle bar. A manually operated hand pulley coupled to the main shaft from the outside, a starting means for starting a sewing process, an on-needle detection means for detecting a needle upper position of the needle bar, and a main shaft An encoder means for generating an encoder signal indicating the rotational phase angle of the main shaft, a phase angle detecting means for detecting the rotational phase angle of the main shaft, a detection signal from the needle upper detecting means and a phase angle detecting means when the sewing machine is started. Rotation direction determination means for determining the rotation direction of the hand pulley that receives the phase angle information and moves the needle bar to the needle upper position along the shortest path when the needle bar is not in the needle upper position, and rotation of the spindle received from the rotation direction determination means Notify directions And a knowledge unit, when the starting means has started operation, when the needle bar is not needle up position, after moving the needle bar to the needle upper position by the manual operation of the hand pulley, sewing process is started It is comprised as follows.

  When the sewing machine motor is driven during sewing, the needle bar is reciprocated up and down by the rotation of the main shaft, so the sewing needle attached to this needle bar and the thread catcher driven in synchronism with this needle Thus, stitches are formed on the work cloth. By the way, when the sewing process is completed, the needle bar generally stops at its uppermost position, and the next sewing is started from the upper needle position.

  However, when the needle bar is lowered to a position other than the needle up position at the start of the next sewing, the rotation direction determination means detects the detection signal detected by the needle up detection means and the phase angle detection means. Since the rotation direction of the main shaft for moving the needle bar to the needle upper position along the shortest path is determined based on the rotation phase angle of the main shaft, the rotation direction of the main shaft is notified by the notification means. Therefore, when the operator rotates the main shaft in the notified rotation direction, the needle bar is quickly moved to the needle upper position.

  A sewing machine according to a second aspect of the present invention is the sewing machine according to the first aspect, further comprising an operation panel capable of displaying the rotation direction of the main shaft received from the rotation direction determination unit, and the notification unit configured by the operation panel.

  According to a third aspect of the present invention, the sewing machine according to the second aspect is provided with error display means for receiving a detection signal from the needle up detection means when the sewing machine is started and displaying an error in the needle up position when the needle bar is not in the needle upper position. It is a thing.

  A sewing machine according to a fourth aspect of the present invention is the sewing machine according to the third aspect, wherein the sewing machine is a dovetail hole sewing machine having a needle swinging mechanism that causes the needle bar to swing alternately between the inner needle position and the outer needle position. Needle bar position detecting means for detecting whether the inner needle sewing cycle extends over a phase angle of 360 ° or the outer needle sewing cycle extended over a rotation phase angle of the main shaft of 360 ° is provided. It receives a detection signal from the bar position detecting means and determines the rotation direction of the main shaft that moves the needle bar to the upper position of the inner needle with the shortest path.

According to the first aspect of the present invention, the needle bar which is reciprocated up and down through the main shaft by the sewing machine motor and the thread which supplements the thread loop of the upper thread in cooperation with the sewing needle attached to the lower end of the needle bar. In a sewing machine equipped with a wheel catching means, a manually operated hand pulley, an activation means, a needle up detection means, a phase angle detection means, a rotation direction determination means, and a notification means are provided, and the activation means starts operation. the sewing machine startup that is, when the needle bar is not needle up position, the rotation direction of the hand pulley to move the needle bar to the needle on the position is notified prior to the sewing process of sewing is started, the operator The needle bar can be quickly moved to the needle upper position only by rotating the main shaft based on the notified rotation direction.

  Therefore, at the start of sewing, even if the needle bar is in a position other than the needle up position, the movement operation of the needle bar to the needle up position can be speeded up and simplified, and the next sewing can be started quickly. The sewing cycle time can be greatly shortened.

  According to the invention of claim 2, since the operation panel capable of displaying the rotation direction of the spindle received from the rotation direction determination means is provided and the notification means is constituted by the operation panel, the operator can display via the display on the operation panel. Thus, it is possible to easily and accurately know the rotation direction of the spindle notified. Other effects similar to those of the first aspect are obtained.

  According to the invention of claim 3, the error display means is provided for receiving the detection signal of the needle up detection means at the time of starting the sewing machine and displaying a needle up position error when the needle bar is not in the needle up position. The operator can easily and clearly recognize that the needle bar is not in the needle up position by the displayed needle up position error. Other effects similar to those of the second aspect are achieved.

  According to a fourth aspect of the present invention, the sewing machine is a dovetail-holed sewing machine having a needle swing mechanism that swings the needle bar alternately between the inner needle position and the outer needle position, and is provided with a needle bar position detecting means, The direction determination means receives the detection signal from the needle bar position detection means when the sewing machine is started, and determines the rotation direction of the main shaft that moves the needle bar to the upper position of the inner needle with the shortest path. When starting from the needle position error display, it is easy to see that the needle bar is not in the upper position of the inner needle, and the rotation direction of the spindle that moves the needle bar to the upper position of the inner needle is displayed in the shortest path. Therefore, the operator only needs to rotate the main shaft in the displayed rotation direction, and the needle bar can be quickly moved to the position above the inner needle, and the sewing cycle time can be greatly shortened. . Other effects similar to those of the third aspect are achieved.

  In the case of the “needle up position error” at the start of sewing, the eyelet sewing machine of this embodiment moves the needle bar to the upper position of the inner needle to release the “needle up position error”. Is displayed.

  As shown in FIG. 1 and FIG. 2, the eyelet sewing machine 1 forms an eyelet seam and an eyelet hole, and a bed base 2 having a substantially rectangular box shape opened upward, and the bed base. 2, a bed portion 3 placed so as to be fitted in 2, a pedestal portion 4 standing from the rear portion of the bed portion 3, and an arm portion 5 extending forward from the upper portion of the pedestal portion 4. In addition, it is placed and fixed on the sewing machine table T.

  An operation panel 6 is provided on the upper side of the sewing machine table T, and a control box 9 containing a control device 20 including a microcomputer for controlling the operation of each mechanism is provided on the lower side of the sewing machine table T. The operation panel 6 is provided with a liquid crystal display 7 and switches 8 including a plurality of operation switches. Therefore, the operator is instructed through the liquid crystal display 7 to perform various operations such as selecting one of a plurality of types of eyelet stitches.

  By the way, although not shown, the main shaft is disposed in the front-rear direction in the arm portion 5 and is rotatably supported by the machine frame at a plurality of locations. In the substantially central portion of the arm portion 5 in the front-rear direction, a secondary shaft that three-dimensionally intersects with the main shaft is disposed in the left-right direction, and a hand pulley 10 is fixed to one end portion of the secondary shaft.

  The main shaft is directly driven by a sewing machine motor 40 (see FIG. 3) through a timing belt, and the sub shaft is connected to the main shaft through a hypoid gear. Therefore, when the operator manually rotates the hand pulley 10 counterclockwise (forward direction) or counterclockwise (reverse direction), the main shaft rotates in a predetermined rotation direction and an anti-predetermined rotation direction via the auxiliary shaft. To do.

  As shown in FIG. 2, a needle bar 12 having a sewing needle 11 is provided at the lower end of the arm portion 5 so as to be movable up and down. Although not shown in detail, the rotational force of the main shaft that is rotated by the driving of the sewing machine motor 40 Is transmitted to the cam mechanism, and the needle bar 12 is driven up and down while swinging left and right by a predetermined needle swing width by the needle swing mechanism. In this case, every time the main shaft rotates twice by the sewing machine motor 40, the needle bar 12 swings between a left swing position (inner needle position) and a right swing position (outer needle position).

  The bed 3 is provided with a looper base 14 provided with two loopers (not shown) so as to face the needle bar 12, and these two loopers rotate the main shaft via a cam mechanism (not shown). Thus, the needle bar 12 is driven in synchronism with the vertical movement. Further, the needle bar 12 and the looper base 14 are rotated around the vertical axis in the horizontal plane by a rotation mechanism (not shown) including a θ-direction drive motor 42 (see FIG. 3) and a gear mechanism provided in the bed portion 3, respectively. It is designed to rotate integrally.

  The bed 3 is detachably attached with a knife 15 for forming a eyelet hole fixedly positioned on the rear side of the looper base 14 and is used for punching that contacts and separates from the knife 15 from above. A hammer 16 is provided so as to be swingable.

  A hammer 17 is detachably attached to the tip of the punching hammer 16. The punching hammer 16 is driven by a hammer driving mechanism including an air cylinder (not shown) provided in the bed portion 3, and the hammer 17 and the knife 15 cooperate with each other to connect to the substantially circular eyelet hole portion. Eyelet holes made of straight leg hole portions are drilled in the work cloth.

  As shown in FIGS. 1 and 2, a feed base 18 on which the work cloth is placed is provided on the upper surface of the bed 3. The feed base 18 has a thin rectangular box shape as a whole, and a portion facing the looper base 14 and the knife 15 is open. Further, although not shown, a pair of left and right cross plates made of metal are provided on the upper surface of the feed base 18, respectively.

  In the bed 3, an X-direction moving mechanism (not shown) for moving the feed base 18 in the X direction (left and right direction) by driving an X direction drive motor 47 (see FIG. 3) comprising stepping, and a stepping There is provided a Y-direction moving mechanism (not shown) that feeds and moves in the Y-direction (front-rear direction) by driving a Y-direction drive motor 49 (see FIG. 3) that is a motor.

  Next, an outline of the control system of the eyelet-holed sewing machine 1 will be described based on the block diagram of FIG.

  The control device 20 housed in the control box 9 of the eyelet sewing machine 1 is connected to a microcomputer including a CPU 21, a ROM 22, a RAM 23, a non-volatile memory 24, and the like via a common bus 25 such as a data bus. The input interface 26, the output interface 27, and the like.

The input interface 26 includes a start / stop switch 30 (starting means) , a presser foot switch 31 connected to a presser foot ( not shown ) , a needle upper position detection sensor 32 for detecting the needle upper position of the needle bar 12, and a needle. A needle position detection sensor 33 that detects the needle position of the bar 12, a needle bar position detection sensor 34 that detects the swing position of the needle bar 12, and an X direction origin sensor that sets the X direction origin position of the feed base 18. 35, a Y-direction origin sensor 36 for setting the Y-direction origin position of the feed base 18, a θ-direction origin sensor 37 for setting the θ-direction origin position of the θ-direction drive motor 42, and the operation panel 6 are connected. .

  The needle upper position detection sensor 32 is composed of a proximity switch, and reacts to a protrusion formed over a predetermined range on a needle upper disk provided integrally with the auxiliary shaft, thereby rotating the rotation phase angle “of the main shaft. A needle up signal of “H” level is output over the range of 337.5 to 22.5 ° (about 45 °). The under-needle position detection sensor 33 includes a proximity switch, and reacts to a protrusion formed over a predetermined range on a under-needle disk provided integrally with the auxiliary shaft, so that the rotational phase of the main shaft is detected. The needle down signal of “H” level is output over the range of angle “157.5-202.5 °” (about 45 °).

  Here, as shown in FIG. 5, the range of the rotation phase angle of 45 ° of the main shaft in which the “H” level needle up signal is output from the needle up position detection sensor 32 is the needle up position. The range where the needle bar position signal is at the “H” level and the needle up signal is at the “H” level is the inner needle upper position.

  The needle bar position detection sensor 34 includes a proximity switch, and responds to a protrusion formed over a predetermined range on a needle bar swinging position disk integrally provided on the countershaft. Output the needle bar position signal of “H” level over the inner needle sewing cycle corresponding to the rotation phase angle “360 °” of the main shaft including the upper needle position (see FIG. 5), and the rotation phase angle of the main shaft An “L” level needle bar position signal is output over the outer needle sewing cycle corresponding to “360 °” (see FIG. 5). Specifically, the rotation phase angle of the main shaft at the needle upper position is 360 °, which is 180 ° in the front-rear direction.

  From the output interface 27, a drive circuit 41 for a sewing motor 40 composed of an AC servo motor, a drive circuit 43 for a θ-direction drive motor 42, and an electromagnetic cylinder connected to an air cylinder 44 that drives the punching hammer 16. A drive signal is supplied to a drive circuit 46 for the switching valve 45, a drive circuit 48 for the X-direction drive motor 47 that moves and drives the feed base 18, and a drive circuit 50 for the Y-direction drive motor 49, respectively. .

  Here, an encoder disk (not shown) in which 180 fine lines are drawn radially at equal intervals is fixed to the drive shaft of the sewing machine motor 40, and a phase angle sensor 51 is provided so that the encoder disk can be read. That is, when the drive shaft of the sewing machine motor 40 is rotated by a rotational phase angle of 2 °, the phase angle sensor 51 outputs one encoder signal to the input interface 26.

  The ROM 22 receives input signals input from the plurality of switches 30, 31 and the plurality of sensors 32 to 37, and executes a sewing machine control program for driving the motors 40, 42, 47, 49 and an encoder signal from the phase angle sensor 51. A rotation phase angle detection program for detecting the rotation phase angle of the main shaft and a control program for needle position error display control unique to the present application, which will be described later, are stored. In addition, the RAM 23 is provided with various work memories, buffers, pointers, and the like in addition to the sewing data memory for storing the created sewing data for the eyelet hole stitching at the time of eyelet stitching.

  Here, the sewing machine motor 40 is configured to rotate once and the main shaft rotates once. Further, the rotational phase angle of the main shaft is detected while sequentially counting the encoder signal received from the phase angle sensor 51 by the rotational phase angle detection control program described above. Furthermore, the count value of the encoder signal is the timing when the spindle rotates once and counts to “0, 1, 2,... 179”, that is, the timing when the needle up signal falls from “H” level to “L” level. It is reset (cleared) by the reset signal output at.

  Next, the routine of the needle up position error display control executed by the control device 20 of the eyelet sewing machine 1 will be described based on the flowchart of FIG. Here, when starting the sewing of the eyelet hole stitching, the sewing needle 11 does not interfere with the feeding base 18 when the feeding base 18 is moved in order to position the sewing start position of the work cloth directly below the sewing needle 11. In addition, this needle up position error display control is executed so that the needle bar 12 is always moved to the upper position of the inner needle. However, in the figure, reference sign Si (i = 11, 12, 13,...) Represents each step.

When starting and stopping switch 30 is operated to start the sewing process, prior to the sewing process is started, the needle on the position error display control is started. When this control is started, first, a needle bar position signal output from the needle bar position detection sensor 34 is read (S11). This read needle bar position signal is at “H” level, that is, the needle bar 12 is rotated by the inner needle sewing cycle (the rotation of the main shaft including the upper position of the inner needle of the needle bar 12 where the rotation phase angle of the main shaft is 0 °). At the time of the sewing cycle (phase angle 360 °) (S12: Yes), the needle up signal output from the needle up position detection sensor 32 is read (S13).

  Next, when this needle up signal is “H” level and the needle bar 12 is in the needle up position (S14: Yes), the needle bar 12 is in the needle up position and sewing can be started immediately. Therefore, this control is terminated without displaying any needle up position error.

  On the other hand, when the position is not the needle up position (S14: No), when the count value E of the encoder signal is “0 ≦ E ≦ 79” (S15: Yes), the “needle up position error” is displayed on the liquid crystal display 7 ( S18) Since rotating the hand pulley 10 in the reverse direction can move the needle bar 12 to the upper position of the inner needle through the shortest path, a screen for instructing the reverse rotation direction is displayed on the liquid crystal display 7 (S19). .

  However, when the count value E of the encoder signal is “80 ≦ E ≦ 157” (S15: No), rotating the hand pulley 10 in the forward direction moves the needle bar 12 to the upper position of the inner needle with the shortest path. Since this is possible, the “needle up position error” is displayed on the liquid crystal display 7 (S16), and a screen for instructing the forward rotation direction is displayed on the liquid crystal display 7 (S17).

  On the other hand, the read needle bar position signal is at the “L” level and the needle bar 12 is in the outer needle sewing cycle (the rotation of the main shaft including the upper needle needle position of the needle bar 12 where the rotation phase angle of the main shaft is 0 °). When the phase value of the encoder signal is “80 ≦ E ≦ 170” (S20: Yes) at the time of the sewing cycle (phase angle 360 °) (S12: No), the “needle up position error” is displayed on the liquid crystal display 7. Is displayed (S18), and when the hand pulley 10 is rotated in the reverse direction, the needle bar 12 can be moved to the upper position on the inner needle by the shortest path, so a screen for instructing the reverse rotation direction is displayed on the liquid crystal display 7. (S19).

  However, when the count value E of the encoder signal is “171 ≦ E ≦ 179” or “0 ≦ E ≦ 79” (S20: No), the needle bar 12 is shortened by rotating the hand pulley 10 in the forward direction. Since it is possible to move to the upper needle needle position on the route, the “needle upper position error” is displayed on the liquid crystal display 7 (S16), and a screen for instructing the forward rotation direction is displayed on the liquid crystal display 7 (S17).

Therefore, when the operator refers to the displayed rotation direction and manually rotates the hand pulley 10 in the reverse direction or the forward direction, the needle bar 12 is in the inner needle sewing cycle and the upper position of the inner needle needle is reached. To the shortest path. At this time, the “needle up position error” is not displayed on the liquid crystal display 7 and the sewing process of the sewing machine 1 is started after the manual operation completes the movement of the needle bar 12 to the inner needle up position.

Next, the operation and effect of the needle up position error display will be described with reference to FIG.
For example, when the needle bar 12 is in the “reverse rotation range A”, the count value E of the encoder signal is “0 ≦ E ≦ 79”, and therefore, as shown in FIG. "The position is out of position" and the rotation direction of the hand pulley 10 "reverse rotation direction", that is, the reverse rotation direction of the spindle is displayed at the same time.

  Similarly, when the needle bar 12 is in the “reverse rotation range B”, the count value E of the encoder signal is “80 ≦ E ≦ 170”. Indicates that the direction of rotation of the hand pulley 10 is “reverse rotation direction”, that is, the reverse rotation direction of the main shaft is displayed at the same time.

  On the other hand, when the needle bar 12 is in the “forward rotation range C”, the count value E of the encoder signal is “171 ≦ E ≦ 179” and “0 ≦ E ≦ 79”. Therefore, as shown in FIG. The display 7 simultaneously displays the direction of rotation of the hand pulley 10 “forward rotation direction”, that is, the forward rotation direction of the main shaft, at the same time.

  Further, when the needle bar 12 is in the “forward rotation range D”, similarly, the count value E of the encoder signal is “80 ≦ E ≦ 157”. Therefore, as shown in FIG. Indicates that the rotation direction of the hand pulley 10 is “forward rotation direction”, that is, the forward rotation direction of the main shaft is simultaneously displayed.

Here, the needle up position detection sensor 32 and the like correspond to needle up detection means. Further, the phase angle sensor 51 and the like correspond to the encoder means. The control device 20 that executes the rotational phase angle detection program corresponds to the phase angle detection means. Also, the rotation direction of the hand pulley 10 that causes the control device 20 that executes S11 to S15 and S20 of the needle up position error display control to move the needle bar 12 to the needle up position along the shortest path when the needle bar 12 is not in the needle up position. It corresponds to the determination means. Further, the operation panel 6 having the liquid crystal display 7 and the control device 20 that executes S17, S19, etc. of the needle up position error display control correspond to the notification means. The control device 20 that executes S17, S19, etc. of the needle up position error display control corresponds to the error display means. Further, the control device 20 that executes S12 and the like of the needle up position error display control corresponds to the needle bar position detecting means.

  As described above, regarding the position of the needle bar 12 at the start of sewing in which the eyelet hole sewing machine 1 is used, the needle bar position signal (“H” or “L” level signal) and the needle up signal are obtained. (“H” or “L” level signal) and the count value E of the encoder signal are read, and based on these signals, when the needle bar 12 is not in the upper position of the inner needle, the needle bar 12 is moved to the shortest path. Thus, the rotation direction of the main shaft to be moved to the upper position of the inner needle, that is, the rotation direction of the hand pulley 10 is notified by display on the liquid crystal display 7, so that the operator rotates the hand pulley 10 based on the notified rotation direction. Only the needle bar 12 can be quickly moved to the upper position of the inner needle with the shortest path.

  Therefore, even when the needle bar 12 is in a position other than the position above the inner needle, manual operation of the hand pulley 10 by the operator can be greatly simplified. As a result, the next sewing operation can be started quickly, and the sewing cycle time can be greatly shortened.

  Further, in this case, since the fact that the needle bar 12 is not in the needle upper position is indicated by characters on the liquid crystal display 7, the operator displays that the needle bar 12 is not in the needle upper position. It is possible to easily and clearly recognize the error due to the above needle position error.

Next, a modified embodiment in which the embodiment is partially modified will be described.
1) At the start of sewing, the needle bar 12 may be recognized by the special background color of the liquid crystal display 7 that the needle bar 12 has not moved to the upper position of the inner needle. You may make it understand by lighting or blinking of a lamp for exclusive use of an upper position error.

2) The operator may be made to recognize that this is an upper needle needle position error by sounding an alarm buzzer or by voice guidance using a speaker.

3) Instead of determining “the needle bar is placed higher in the needle?” In S14 of the needle upper position error display control, it is determined whether or not the count value E of the encoder signal is within the range of “157 ≦ E ≦ 179”. You may do it.

4) The count value from the count value E of the encoder signal to the upper position of the inner needle may be calculated, and the count value may be displayed on the liquid crystal display 7. At that time, the color displayed on the liquid crystal display 7 may be changed according to the calculated count value.

5) In the present embodiment, the hand pulley 10 is integrally connected to the main shaft, but may be indirectly connected via a gear.

6) The present invention is not limited to the embodiment described above, and those skilled in the art can implement the present invention by adding various modifications without departing from the spirit of the present invention. The present invention includes such modifications.

1 is a perspective view of an eyelet hole sewing machine according to an embodiment of the present invention. It is a side view of an eyelet-punching sewing machine. It is a block diagram of a control system of the eyelet hole sewing machine. It is a flowchart of needle up position error display control. It is a time chart which shows the various signals regarding the up-and-down movement of a needle bar, and a needle swing. It is a figure which shows the example of a display of an inner needle needle | hook upper position error and the reverse rotation direction of a hand pulley. It is a figure which shows the example of a display in the forward rotation direction of an inner needle needle upper position error and a hand pulley.

DESCRIPTION OF SYMBOLS 1 Eyelet hole sewing machine 7 Liquid crystal display 10 Hand pulley 11 Sewing needle 12 Needle bar 20 Control device 32 Needle up position detection sensor 34 Needle bar position detection sensor 40 Sewing motor 51 Phase angle sensor

Claims (4)

In a sewing machine comprising a needle bar that is driven to reciprocate up and down via a main shaft by a sewing machine motor, and an annulus catching means that supplements an upper thread thread in cooperation with a sewing needle attached to the lower end of the needle bar ,
A manually operable hand pulley coupled to the main shaft from the outside;
Starting means for starting the sewing process;
Needle up detection means for detecting the needle up position of the needle bar;
Phase angle detection means for detecting encoder rotation phase angle, comprising encoder means for generating an encoder signal indicating the rotation phase angle of the spindle;
A hand pulley that receives a detection signal from the needle up detection means and phase angle information of the phase angle detection means when the sewing machine is started, and moves the needle bar to the needle up position along the shortest path when the needle bar is not in the needle up position; A rotation direction determination means for determining the rotation direction;
Notification means for notifying the rotation direction of the spindle received from the rotation direction determination means,
If the needle bar is not in the needle up position when the activation means is started, the sewing process is started after the needle bar is moved to the needle up position by manual operation of the hand pulley. Characteristic sewing machine.   The sewing machine according to claim 1, further comprising an operation panel capable of displaying a rotation direction of the spindle received from the rotation direction determination unit, and the notification unit configured by the operation panel.   The error display means is provided for receiving a detection signal from the needle up detection means when the sewing machine is activated and displaying a needle up position error when the needle bar is not in the needle up position. sewing machine.   The sewing machine is a dovetail hole sewing machine having a needle swing mechanism that swings the needle bar alternately between the inner needle position and the outer needle position, and the needle bar has an inner needle sewing cycle that extends over a rotation phase angle of 360 ° of the main shaft. And a needle bar position detecting means for detecting whether the rotation phase angle of the main shaft is 360 ° or the outer needle sewing cycle, and the rotational direction determining means detects a detection signal from the needle bar position detecting means when the sewing machine is started. The sewing machine according to claim 3, wherein the rotation direction of the main shaft that moves the needle bar to the upper position of the inner needle needle along the shortest path is determined.

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