JP2010094272A - Surging sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surging sewing machine convenient for a worker, capable of providing a wide working space for the maintenance, and capable of securely preventing false detection by a photosensor caused by adhesion of a foreign substance. <P>SOLUTION: A reflective photosensor 7 is embedded on a sewing machine table 2 in such a state as to face a fabric upper guide surface 6a of a fabric guide 4. A reflection layer 9 is provided at a position facing the reflective photosensor 7 on the fabric upper guide surface 6a of the fabric guide 4. A nozzle 11 for jetting air toward the reflective photosensor 7 is disposed on the upstream side in the direction of feeding from the position where the reflection layer 9 is disposed in the fabric guide 4. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a surging sewing machine that can be edge-stitched along the edges of cut fabrics such as trousers, skirts and shirts.

  2. Description of the Related Art Surging machines that can perform edge stitching along the edges of cut fabric such as trousers, skirts, and shirts are known. As such a surging machine, in order to send the edge of the fabric correctly to the needle drop position, it is fed on the needle plate provided at the needle drop position while moving the fabric left and right according to the shape of the edge. It is necessary to. For this reason, a cloth guide for guiding the cloth toward the needle drop position is attached upstream of the needle drop position on the upper surface of the sewing machine table in the surging sewing machine, for example, upstream of the presser foot. This cloth guide has a cloth end guide surface against which the cloth edge of the cloth abuts, and a cloth guide surface against which the upper surface of the cloth end abuts to prevent the cloth edge of the cloth from rising. (For example, refer to Patent Document 1).

  Further, as a conventional surging sewing machine, an optical sensor for detecting the leading and trailing edges of the cloth in the cloth feeding direction is provided, and the leading edge of the cloth fed into the cloth guide is detected by the optical sensor. Some machines can be started and the driven sewing machine can be stopped by detecting the trailing edge of the fabric with an optical sensor (see, for example, Patent Document 2).

  FIGS. 6 to 8 show an example of a conventional surging sewing machine. The conventional surging sewing machine 101 has a sewing machine table 102 serving as a sewing work table and a sewing machine body 103 that performs edge stitching. . The sewing machine body 103 is attached to a corner of the sewing machine table 102. An overlock sewing machine is used as the sewing machine body 103.

  On the upper surface of the sewing machine table 102, a fabric C (FIG. 7) for sewing toward a needle drop position P (FIG. 8) provided below the sewing needle N supported by the needle bar 107 of the sewing machine body 2 is provided. A cloth guide 104 for guiding is attached. Accordingly, the cloth guide 104 is attached to the upper surface of the sewing machine table 102 on the upstream side in the cloth feeding direction E indicated by the arrow in FIG.

  The cloth guide 104 has a thickness corresponding to the cloth thickness, and includes a spacer 105 having a curved cloth end guide surface 105a against which the cloth edge of the cloth C abuts, and an outer peripheral portion on one side on the upper surface of the spacer 105. And a guide plate 106 attached to the upper surface of the sewing machine table 102 together with the spacer 105. Further, the lower surface of the protruding portion of the guide plate 106 that protrudes outward from the cloth end guide surface 105a is an on-cloth guide surface 106a with which the upper surface of the cloth end edge of the fabric C abuts. Further, the outer peripheral portion of the cloth upper guide surface 106a is formed to bend upward so as to be away from the upper surface of the sewing machine table 102, and the cloth edge of the cloth C is below the cloth guide 104, that is, the sewing machine table 102. Are easily inserted into a guide space G surrounded by the upper surface of the cloth, the cloth edge guide surface 105a, and the cloth upper guide surface 106 (FIG. 7).

  On the side of the sewing machine body 103, above the needle plate 111 of the sewing machine body 103 located upstream of the needle drop position P in the cloth feeding direction E, the leading and trailing ends of the cloth C in the cloth feeding direction E are detected. A reflective optical sensor 112 is provided as an optical sensor. And as shown in FIG. 8, the reflective tape 113 as a reflection layer is affixed on the surface of the needle plate 111 facing this reflective optical sensor 112. That is, the reflection type optical sensor 112 is disposed so as to face the cloth feeding path of the fabric C from above, and is formed so that the optical path of the reflection type optical sensor 112 can be blocked by the cloth C.

  As an optical sensor, there is a configuration using a transmissive optical sensor. In this case, the light projector is disposed above, and the light receiver is disposed on the surface of the needle plate.

  A cloth cutting mechanism (not shown) having a cloth cutting knife 108 (FIG. 8) for cutting the cloth end is provided above the needle plate 111 from the reflective optical sensor 112 to the needle bar 107. A cloth feed mechanism (not shown) having a feed dog for feeding the cloth C is disposed around the needle drop position P of the needle plate 111.

  According to the conventional surging sewing machine 101 having such a configuration, the edge of the fabric C placed on the upper surface of the sewing machine table 102 is guided by the fabric guide 104, so that the edge of the fabric C is correctly needle-dropped. It is sent to position P. Then, the tip of the fabric C in the cloth feeding direction E is detected by the reflection type optical sensor 112, that is, the reflected light Lb emitted from the reflection type optical sensor 112 is reflected by the reflection tape 113 and returned. When the sewing machine is activated based on a detection signal when it is not in operation, for example, “Low” and the rear end of the fabric C is detected by the reflective optical sensor 112, that is, when the reflected light Lb from the reflective tape 113 is received The sewing machine that is being driven is stopped based on the detection signal, for example, “High”. Of course, the operation of the fabric C until the sewing machine is started is performed manually by the operator. In addition, the sewing machine is started and stopped by a sewing machine control unit including a CPU functioning as a calculation unit that controls operation of a movable unit (not shown) and a memory functioning as a storage unit in response to a signal from the optical sensor.

Registered Utility Model No. 2568186 Japanese Patent Publication No. 7-71593

  However, the conventional surging sewing machine 101 has a problem that it is not convenient for the operator.

  For example, in the conventional surging sewing machine 101, as shown in FIGS. 6 and 8, since the reflective optical sensor 112 is disposed in the vicinity of the sewing needle N, the threading operation of passing the thread through the sewing needle N is performed. In addition, there is a problem that the working space is narrow when performing maintenance work such as replacement of the sewing needle N and the cloth cutting knife 108. In particular, when thread is passed through the sewing needle N, since the sewing machine body 103 is a lock sewing machine, it is necessary to pass the thread through the needle hole of the sewing needle N from the upstream side to the downstream side in the cloth feeding direction, and the workability is extremely poor. It was.

  Further, in the conventional surging machine 101, as shown in FIG. 8, since the reflection type optical sensor 112 and the reflection tape 113 are disposed in the vicinity of the cloth cutting knife 108, the cloth cutting knife 108 is used as the cloth cutting knife 108. There is a problem that foreign matter such as dust or dust generated when cutting the cloth edge of C adheres to the reflective optical sensor 112 or the reflective tape 113 and the reflective optical sensor 112 may erroneously detect. There was a point.

SUMMARY OF THE INVENTION The present invention has been made in view of this point, and a surging sewing machine that is easy to use by an operator capable of reliably preventing erroneous detection of an optical sensor due to adhesion of foreign matter with a wide working space when performing maintenance work. The purpose is to provide.
The purpose is to provide.

  In order to achieve the above-mentioned object, the surging sewing machine according to claim 1 of the present invention is characterized by a sewing machine table, a sewing machine body attached to the sewing machine table and performing edge stitching on a fabric, and the sewing machine. In order to guide the cloth placed on the upper surface of the table toward the needle drop position of the sewing machine body, the cloth edge guide surface attached to the sewing machine table and against which the cloth edge of the cloth abuts and the cloth cloth A cloth guide having an on-cloth guide surface with which the upper surface of the end edge abuts, and an optical sensor that is disposed upstream of the needle drop position in the cloth feeding direction and detects the leading and trailing ends of the cloth in the cloth feeding direction. And the optical sensor is activated by a detection signal when the leading edge of the cloth in the cloth feeding direction is detected, and is driven by the detection signal when the trailing edge of the cloth in the cloth feeding direction is detected. In the surging sewing machine configured to stop the sewing machine, the optical sensor is a reflective optical sensor embedded in the sewing machine table so as to face the cloth guide surface, and the cloth guide surface A reflective layer for reflecting the light from the reflective photosensor is provided at a position facing the reflective photosensor of the fabric guide. On the upstream side, a nozzle for injecting air toward the reflective optical sensor is provided.

  By adopting such a configuration, the reflection type optical sensor is embedded in the sewing machine table, and the reflection layer is disposed on the cloth guide surface. Therefore, the sewing needle of the sewing machine body and the cloth cutting knife And it is not necessary to arrange an optical sensor in the vicinity of the knife for cloth cutting. As a result, the optical sensor does not get in the way when performing maintenance work such as threading work to pass the thread through the sewing needle or replacement of the sewing needle and the cloth cutting knife. Therefore, the work space required for the maintenance work can be widened, and the visibility of the sewing position is improved. On the other hand, when the reflective optical sensor is embedded in the sewing machine table and the reflective layer is provided on the cloth guide, foreign matter accumulates in a narrow space between the sewing machine table and the cloth guide, and the reflective optical sensor is liable to malfunction. However, in the surging sewing machine of the present invention, since the nozzle for injecting air toward the reflection type optical sensor is arranged upstream of the arrangement position of the reflection layer of the cloth guide in the cloth feeding direction, the nozzle By spraying air from the cloth, dust and other foreign matters such as dust generated when cutting the cloth with a cloth cutting knife are blown away downstream in the cloth feeding direction. Can be prevented from entering. In addition, the reflective photosensor can be cleaned by air ejected from the nozzle without removing the cloth guide. As a result, even when the reflective optical sensor is embedded in the sewing machine table and the reflective layer is provided on the cloth guide, it is possible to prevent foreign matter from adhering to the reflective optical sensor and malfunctioning. Furthermore, since the air injected from the nozzle flows toward the downstream side in the cloth feeding direction, the cloth inserted into the cloth guide can be urged toward the downstream side in the cloth feeding direction by the flow of this air. As a result, when the fabric is inserted into the fabric guide and then fed toward the needle drop position, the air sprayed from the nozzle can be supplemented, so the slackening is caused by the frictional force between the sewing machine table and the fabric. Even a thin and weak fabric that is prone to wrinkles can be slid smoothly on the sewing machine table. That is, at the beginning of sending the fabric to the needle drop position, sagging and wrinkles can be prevented from occurring on the fabric due to the frictional force between the sewing table and the fabric.

  The surging machine of the present invention according to claim 2 is characterized in that, in claim 1, the arrangement position of the reflective layer of the cloth guide is a transparent portion that transmits light in the thickness direction, The reflective layer is in the point provided in the upper surface or the inside of the said transparent part. By adopting such a configuration, it is possible to reliably and easily prevent the reflection layer from interfering with the movement of the fabric when the fabric is fed to the needle drop position.

  According to the surging sewing machine according to the present invention, the work space for performing maintenance work is wide, and it is possible to reliably prevent erroneous detection of the optical sensor due to the adhesion of foreign matter, so that the convenience for the operator can be improved easily and reliably. Excellent effects such as being able to be made.

  The present invention will be described below with reference to embodiments shown in the drawings.

  FIG. 1 to FIG. 3 show a main part of an embodiment of a surging sewing machine according to the present invention, FIG. 1 is a schematic plan view, and FIG. 2 is an enlarged cross-sectional view taken along line AA in FIG. 3 is an enlarged sectional view taken along line BB in FIG.

  As shown in FIG. 1, the surging sewing machine 1 of the present embodiment has a sewing machine table 2 that is a sewing work table and a sewing machine body 3 that performs edge stitching. The sewing machine body 3 is attached to a corner of the sewing machine table 2. An overlock sewing machine is used as the sewing machine body 3.

  As shown in FIG. 1 to FIG. 3, on the upper surface of the sewing machine table 2, a cloth C used for sewing toward a needle drop position P provided below a sewing needle (see reference numeral N in FIG. 6) of the sewing machine body 3. A cloth guide 4 for guiding (FIG. 2) is attached.

  Accordingly, the cloth guide 4 is attached to the upper surface of the sewing machine table 2 on the upstream side in the cloth feeding direction E indicated by the left-pointing arrow in FIG.

  The cloth guide 4 has a thickness corresponding to the cloth thickness, and has a spacer 5 having a curved cloth end guide surface 5a against which the cloth edge of the cloth C abuts, and an outer peripheral portion on one side on the upper surface of the spacer 5. And a guide plate 6 attached to the upper surface of the sewing machine table 2 together with the spacer 5. Moreover, the lower surface of the overhang | projection part which protruded outside the cloth edge guide surface 5a of the guide plate 6 is made into the cloth upper guide surface 6a with which the upper surface of the cloth edge edge part of the fabric C is contact | abutted. Further, the outer peripheral portion of the cloth upper guide surface 6 a is formed so as to bend upward so as to be away from the upper surface of the sewing machine table 2, and the cloth edge of the cloth C is below the cloth guide 4, that is, the sewing machine table 2. Are easily inserted into a guide space G surrounded by the upper surface, the cloth end guide surface 5a, and the cloth upper guide surface 6a (FIG. 2).

  The guide plate 6 is preferably formed of a transparent resin in the sense that the insertion state of the fabric C can be easily recognized.

  On the upstream side of the needle drop position P of the sewing machine table 2 in the cloth feeding direction E, a reflection type optical sensor 7 as an optical sensor for detecting the leading and trailing ends of the cloth C in the cloth feeding direction E is provided on the cloth guide surface 6a. It is buried so as to face. The reflection type optical sensor 7 is screwed to the sewing machine table 2 from below, and is positioned by a mounting nut 8 so that the front end surface 7a of the reflection type optical sensor 7 is flush with the upper surface of the sewing machine table 2. Yes.

  As exaggeratedly shown in FIGS. 2 and 3, the cloth guide surface 6 a is opposed to the reflection type photosensor 7 as a reflection layer for reflecting light from the reflection type photosensor 7. Tape 9 is affixed. The reflective tape 9 is preferably disposed so that the surface thereof is flush with the guide surface 6a on the cloth or slightly recessed in terms of not peeling off by the cloth C and preventing movement of the cloth C.

  When the guide plate 6 is formed of a transparent resin, a metal plate 10 functioning as a reflective layer may be embedded in the guide plate 6 by insert formation or the like as shown in FIG. Moreover, as shown in FIG. 5, it is good also as a structure which affixes the reflective tape 9 or metal foil which functions as a reflective layer on the upper surface of the guide plate 6. FIG. Note that a metal film functioning as a reflective layer may be provided on the upper surface of the guide plate 6 by plating or the like.

  That is, the reflective layer of the cloth guide 4 may be provided as a transparent part that transmits light in the thickness direction, and the reflective layer may be provided on the top or inside of the transparent part.

  Note that a transmissive optical sensor may be used as the optical sensor. In this case, it is preferable to attach a light receiver having a relatively small dimension in the height direction to the upper surface of the guide plate 6 instead of the reflective tape 9.

  Moreover, as the cloth guide 4, the spacer 5 and the guide plate 6 may be integrally formed.

  Further, the reflection type optical sensor 7 is connected to a sewing machine control unit including a CPU that functions as a calculation unit that controls operation of a movable unit of the sewing machine body 3 (not shown) and a memory that functions as a storage unit. Based on the detection signal when the irradiation light La emitted from the sensor 7 does not receive the reflected light Lb reflected by the reflecting tape 9 and returning, for example, the “Low” signal from the reflective optical sensor 7 The sewing machine can be activated by reception. Further, the rear end of the fabric C is detected by the reflective optical sensor 7, that is, based on the detection signal when the reflected light Lb from the reflective tape 9 is received, for example, by receiving the “High” signal, the reflective optical sensor 7 is driven after a preset delay time has elapsed, or after a predetermined number of stitches has been sewed, so that the sewing corresponding to the distance from the disposition position 7 to the needle drop position P is completed. The sewing machine can be stopped.

  As shown in FIG. 1 and FIG. 3, on the upstream side in the cloth feeding direction E from the position where the reflective tape 9 of the cloth guide 4 is disposed, the compressed air, which is air, is jetted toward the reflective optical sensor 7. A nozzle 11 is attached. The central portion of the upper surface of the nozzle 11 is formed with a mounting screw hole 11a into which a joint (not shown) attached to one end of an air tube for supplying compressed air is screwed. Further, the lower surface of the nozzle 11 is arranged so as to be flush with or slightly recessed with the cloth upper guide surface 6a. Furthermore, a flow path for injecting air in the injection direction J indicated by the diagonally left downward arrow in FIG. 3 in order to inject air toward the reflective optical sensor 7 at the bottom of the mounting screw hole 11a. One end of 11 b is connected, and the other end of the channel 11 b is connected to the lower surface of the nozzle 11. Here, the air injection direction J may be parallel to the cloth feed direction E and toward the downstream side of the cloth feed direction E.

  The number of nozzles 11 is plural, and the plurality of nozzles 11 are arranged in parallel along the cloth feed direction E, arranged in a direction orthogonal to the cloth feed direction E, or along the cloth feed direction E. They may be arranged in a matrix in both the parallel direction and the orthogonal direction.

  The nozzle 11 is always supplied with compressed air when the power of the surging sewing machine 1 is turned on by an electromagnetic valve connected to the other end of the air tube.

  Since the other configuration is the same as that of the conventional surging sewing machine 101, detailed description thereof is omitted.

  Next, the operation of the present embodiment having the above-described configuration will be described.

  In the sewing of the fabric C by the surging sewing machine 1 of the present embodiment, the fabric end of the fabric C is first inserted into the guide space G of the fabric guide 4 by the operator's hands. At this time, until the cloth edge of the cloth C once touches the cloth end guide surface 5 a of the cloth guide 4, the cloth C does not block the optical path of the reflective optical sensor 7, and the leading edge of the cloth C in the cloth feeding direction E It is important that the position is positioned on the upstream side in the cloth feeding direction between the reflective tape 7 and the nozzle 11. Further, compressed air is jetted from the nozzle 11.

  Next, in a state where the fabric end of the fabric C is inserted into the guide space G of the fabric guide 4 and with the assistance of compressed air from the nozzle 11, the tip of the fabric C is directed toward the needle drop position P. The cloth C is slid on the upper surface of the sewing machine table 2 and fed. When the tip of the fabric C reaches the position where the reflective optical sensor 7 is disposed, the optical path of the reflective optical sensor 7 is interrupted by the fabric C, the reflective optical sensor 7 operates, and the sewing machine is activated by the detection signal. To do.

  Next, when the fabric C is further slid and fed on the upper surface of the sewing machine table 2, the fabric C is automatically fed by a feed dog of the fabric feed mechanism and a fabric presser (not shown) to start sewing.

  Next, when the rear end of the fabric C exceeds the position where the reflective photosensor 7 is disposed, the optical path of the reflective photosensor 7 is released and the reflective photosensor 7 operates, and the location where the reflective photosensor 7 is disposed. Stop the driven sewing machine after a preset delay time has elapsed so that the sewing for the distance to the needle drop position P is completed, or after the predetermined number of stitches is finished. To do.

  Thus, according to the surging sewing machine 1 of the present embodiment, the reflection type optical sensor 7 embedded in the sewing machine table 2 and the reflection tape 9 as the reflection layer disposed on the cloth guide surface 6a, The leading edge and the trailing edge of the cloth C in the cloth feeding direction E can be reliably detected.

  Further, according to the surging sewing machine 1 of the present embodiment, the reflective optical sensor 7 as the optical sensor is embedded in the sewing machine table 2, and the reflective tape 9 as the reflective layer is disposed on the cloth guide surface 6a. Therefore, it is not necessary to arrange the reflection type optical sensor 7 in the vicinity of the sewing needle N of the sewing machine body 3. As a result, the reflection type optical sensor 7 does not get in the way when performing maintenance operations such as threading operation for passing the thread through the sewing needle and replacement of the sewing needle and the cloth cutting knife. Therefore, the work space required for the maintenance work can be widened, and the visibility of the sewing position is improved.

  Furthermore, according to the surging sewing machine 1 of the present embodiment, air is jetted toward the reflective optical sensor 7 upstream of the arrangement position of the reflection tape 9 as the reflection layer of the cloth guide 4 in the cloth feeding direction E. Since the nozzle 11 is disposed, foreign matter such as dust and dust generated at the time of cutting the fabric by the cloth cutting knife is discharged downstream in the cloth feeding direction by injecting air from the nozzle 11. Can be blown away. Further, the air jetted from the nozzle 11 reliably and easily allows the reflection type optical sensor 7, more specifically, the tip surface 7a used for emission of the irradiation light La and reception of the reflection light Lb, without removing the cloth guide 4. Can be cleaned. As a result, even when the reflective optical sensor 7 is embedded in the sewing machine table 2 and the reflective tape 7 is provided on the cloth guide 4, foreign matter adheres to the front end surface 7a of the reflective optical sensor 7 and erroneous detection (malfunction). Therefore, it is possible to realize the arrangement of the reflection type optical sensor 7 at the position that faces the sewing machine table 2, that is, the cloth feeding path from below.

  Furthermore, according to the surging sewing machine 1 of the present embodiment, since the air injected from the nozzle 11 flows toward the downstream side in the cloth feeding direction E, the cloth C inserted into the cloth guide 4 is caused to flow by this air flow. It is possible to urge toward the downstream side in the cloth feeding direction E. As a result, when the cloth C is inserted into the cloth guide 4 and then fed toward the needle drop position P, the air injected from the nozzle 11 can be supplemented, so that the sewing machine table 2 and the cloth C Even if the fabric C is thin and weak, which is liable to sag and wrinkle due to frictional force, it can be smoothly slid on the sewing machine table 2. That is, when the fabric is fed to the needle drop position, sagging and wrinkles can be prevented from occurring in the fabric C due to the frictional force between the sewing machine table 2 and the fabric C.

  Therefore, according to the surging sewing machine 1 of the present embodiment, the work space for performing the maintenance work is wide, and it is possible to reliably prevent erroneous detection of the reflective optical sensor 7 as the optical sensor due to adhesion of foreign matter. Usability by the operator can be improved easily and reliably.

  Furthermore, according to the surging sewing machine 1 of the present embodiment, since the guide plate 6 of the cloth guide 4 is formed of a transparent resin, the metal plate 10 functioning as a reflective layer is inserted into the guide plate 6 by insert formation or the like. The reflective tape 9 or metal foil functioning as a reflective layer can be attached to the upper surface of the guide plate 6. That is, the arrangement position of the reflective layer of the cloth guide 4 can be a transparent part that transmits light in the thickness direction, and the reflective layer can be provided on the upper surface or inside the transparent part. By adopting such a configuration, when the fabric C is fed to the needle drop position P, it is possible to reliably and easily prevent the reflection layer from interfering with the movement of the fabric C. The movement can be made smoother.

  According to the surging sewing machine 1 of the present embodiment, since the optical path of the reflective optical sensor 7 is provided in the guide space G, the reflective optical sensor 7 as the optical sensor and the reflective tape 9 as the reflective layer are provided. Since the optical path distance between them is almost the same as the thickness of the fabric C, the optical path distance can be made shorter than before, for example, about 1/10. As a result, the detection accuracy and responsiveness of the reflective photosensor 7 can be improved, the sensor sensitivity can be easily adjusted, and the optical path of the reflective photosensor 7 can be blocked by the operator's hand. This contributes to improved safety.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible as needed.

Schematic top view which shows the principal part of embodiment of the surging sewing machine which concerns on this invention Expanded sectional view along the line AA in FIG. Expanded sectional view along the line BB in FIG. Explanatory drawing which shows the other example of the arrangement | positioning position of the reflective layer in embodiment of the surging sewing machine which concerns on this invention. Explanatory drawing which shows the further another example of arrangement | positioning position of the reflective layer in embodiment of the surging sewing machine which concerns on this invention. External perspective view showing a main part of an example of a conventional surging sewing machine The expanded sectional view which shows the principal part of the cloth guide of FIG. 6 seeing from the upstream of a cloth feed direction. Side view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surging sewing machine 2 Sewing machine table 3 Sewing machine body 4 Cloth guide 5 Spacer 5a Cloth end guide surface 6 Guide plate 6a Cloth top guide surface 7 Reflection type optical sensor 9 Reflective tape 11 Nozzle C Cloth E Cloth feed direction G Guide space J (Air ) Injection direction P Needle entry position N Sewing needle

Claims (2)

Sewing machine table,
A sewing machine body attached to the sewing machine table and performing edge stitching on the fabric;
In order to guide the cloth placed on the upper surface of the sewing machine table toward the needle drop position of the sewing machine body, the cloth edge guide surface and the cloth are attached to the sewing machine table and contacted with the cloth edge of the cloth. A cloth guide having an on-cloth guide surface against which the upper surface of the cloth edge is abutted;
An optical sensor that is disposed upstream of the needle drop position in the cloth feeding direction, and that detects the leading and trailing ends of the cloth in the cloth feeding direction;
The sewing machine is started based on a detection signal when the optical sensor detects the leading edge of the cloth in the cloth feeding direction, and the sewing machine driven by the detection signal when the trailing edge of the cloth in the cloth feeding direction is detected is stopped. In a surging sewing machine formed as follows:
The optical sensor is a reflective optical sensor embedded in the sewing machine table so as to face the cloth guide surface;
A reflective layer for reflecting light from the reflective photosensor is provided at a position facing the reflective photosensor on the cloth guide surface,
A surging machine characterized in that a nozzle for injecting air toward the reflection type optical sensor is arranged upstream of the arrangement position of the reflection layer of the cloth guide in the cloth feeding direction.   An arrangement position of the reflective layer of the cloth guide is a transparent part that transmits light in a thickness direction, and the reflective layer is provided on an upper surface or inside of the transparent part. The surging sewing machine according to claim 1.

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