JP4674706B2 - sewing machine - Google Patents

Description

  The present invention protrudes on one side of the sewing machine body, such as a vertical cylindrical sewing machine provided with a feeding device that applies a feed in the axial length direction to the tip of a cylindrical bed protruding on one side of the sewing machine body. Further, the present invention relates to a sewing machine configured such that a needle bar at the tip of the sewing machine arm is moved up and down by transmission from a sewing machine main shaft that is installed so as to be substantially orthogonal to the sewing machine arm inside the sewing machine body.

  Cylindrical portions such as sleeves and torso portions of various clothing items are formed by forming a fabric cut into a predetermined shape into a cylindrical shape and sewing the edges overlapped appropriately in width. Conventionally, in order to perform such sewing, a tubular fabric is passed through the distal end of a thin cylindrical bed, and the feed is directed toward the base end side in the axial length direction of the cylindrical bed, and is sewn. A so-called vertical cylindrical sewing machine is used.

  This sewing machine has a feeding device and a looper under a needle plate installed at the tip of the cylindrical bed, and includes a needle bar and a presser bar suspended from the tip of the sewing machine arm facing the top of the cylindrical bed. It has a needle and presser foot attached to the lower end. The fabric to be sewn is held between the presser foot and the needle plate on the throat plate, and the above-mentioned feed is applied by the operation of the feed device, and the sewing is performed by the operation of the needle and the looper generated in synchronization with this feed. . In addition, the tubular sewn product obtained in a state of being pushed into the proximal end portion of the cylindrical bed by this sewing raises the presser foot, and is drawn out to the distal end side of the tubular bed and collected.

As a vertical cylindrical sewing machine as described above, a sewing machine having a sewing machine arm and a cylindrical bed projecting on one side of the sewing machine main body containing the main spindle of the sewing machine so as to be substantially parallel to each other at positions separated vertically. (For example, refer to Patent Documents 1 and 2).
Republic of China Patent No. 439802 Republic of China Patent No. 503948

  In the vertical cylindrical sewing machine configured as described above, the needle bar provided at the tip of the sewing machine arm, the feed device and the looper provided at the tip of the cylindrical bed are provided from the sewing machine main shaft built in the sewing machine body. Each operation is performed by transmission.

  Here, the main spindle of the sewing machine is intended to simplify the structure of the transmission mechanism to the feeding device and the looper, and also to secure a foot space for a sewing manufacturer who works directly against the tip of the cylindrical bed. For the purpose of facilitating connection with a sewing machine motor arranged in a direction orthogonal to the shape bed, it is installed at the lower part of the sewing machine body in a direction substantially perpendicular to the axial length direction of the cylindrical bed and the sewing machine arm.

  However, when the main shaft of the sewing machine is installed in this way, the main shaft of the sewing machine that is substantially parallel to the protruding direction of the sewing machine arm as a transmission mechanism to the needle bar provided at the tip of the sewing machine arm that extends in a direction substantially orthogonal thereto. It is impossible to use the same transmission mechanism as a general sewing machine provided with a machine. In Patent Document 1, a long swing arm that extends over substantially the entire length of the sewing machine arm is vertically moved by a halfway support shaft. The tip of the swing arm is connected to the needle bar, and the base end is also connected to the crank provided in the middle of the machine main shaft via the crank arm. A transmission mechanism is used that converts the swing arm to swing, transmits the vertical movement of the tip of the swing arm to the needle bar, and moves the needle bar up and down.

  Further, in Patent Document 2, a transmission shaft that repeatedly rotates around the entire axis of the sewing machine arm is disposed inside the sewing machine arm, and the tip of the transmission shaft is connected to the needle bar via the arm and the link. Similarly, the base end is connected to a crank provided in the middle of the sewing machine spindle via a crank arm, and the rotation of the sewing machine spindle is converted into a repetitive rotation of the transmission shaft. A transmission mechanism is used which is configured to convert the needle bar into vertical movement by the arm and the link.

  However, the configuration disclosed in Patent Document 1 includes a bulky swinging arm that swings inside the sewing machine arm, and a bulky crank arm that moves up and down inside the sewing machine body. There is a problem that a large vibration and a sound accompanying the vibration are generated during operation of the sewing machine due to the reaction force caused by the operation. Similarly, in the sewing machine disclosed in Patent Document 2, a bulky crank arm is also provided. There is a problem in that vibration and sound are generated due to the vertical movement of the sewing machine, and there is a difficulty in increasing the sewing speed.

  Further, in the vertical cylinder sewing machine as described above, as in many industrial sewing machines, a built-in device such as a top decoration device may be provided at the tip of the sewing machine arm. In the sewing machine disclosed in 1), the transmission mechanism to these built-in devices has a complicated structure that requires bulky parts as well as the transmission mechanism to the needle bar, and these transmission mechanisms are transmitted to the needle bar. There is a problem that the structure inside the sewing machine arm arranged together with the mechanism becomes complicated.

  The present invention has been made in view of such circumstances, and is a sewing machine including a vertical cylindrical sewing machine or the like that has a sewing machine arm protruding in a direction substantially orthogonal to the main spindle of the sewing machine. Providing a sewing machine that can smoothly transmit power from the main shaft while preventing generation of vibration and sound, and that can be simply configured including the power transmission mechanism to the built-in device provided at the tip of the sewing machine arm. The purpose is to do.

A sewing machine according to a first aspect of the present invention is a sewing machine body having a sewing machine main shaft built in a lower part thereof, a sewing machine arm projecting from the upper part of the sewing machine body in a direction substantially orthogonal to the sewing machine main spindle, and a tip of the sewing machine arm And a needle bar supported by the needle bar, wherein the needle attached to the lower end of the needle bar is moved up and down by transmission from the main spindle of the sewing machine. A transmission shaft installed substantially parallel to the main shaft, a first transmission belt stretched between the transmission shaft and the sewing machine main shaft, and transmitting rotation of the sewing machine main shaft to the transmission shaft; and the sewing machine arm A needle bar drive shaft installed in the vicinity of the needle bar on the inner side of the tip of the sewing machine so as to be substantially parallel to the sewing machine main shaft and the transmission shaft, and stretched between the needle bar drive shaft and the transmission shaft, Rotation of the transmission shaft to the needle bar drive shaft And a motion converting means for converting the rotation of the needle bar drive shaft into the vertical movement of the needle bar, which extends vertically along the outer surface of the sewing machine body and is bent at the top. A belt chamber extending toward the tip along the outer surface of the sewing machine arm is provided independently from the inside of the sewing machine body and the sewing machine arm, and the first transmission belt is connected to the sewing machine into the belt chamber. The second transmission belt is stretched between transmission pulleys fitted to the main shaft and the projecting ends of the transmission shaft, respectively, and the second transmission belt is respectively inserted into the needle bar drive shaft and the projecting ends of the transmission shaft into the belt chamber. Ri stretched Citea during fitting has been a transmission pulley, the belt chamber, characterized tare Rukoto it possible to open and close by the cover plate.

In the present invention, a transmission shaft that is substantially parallel to the sewing machine main shaft is installed at a height position corresponding to the protruding portion of the sewing machine arm inside the sewing machine body, and a first shaft is provided between the transmission shaft and the sewing machine main shaft. The transmission belt is stretched to transmit the rotation of the sewing machine main shaft to the transmission shaft by belt transmission. In addition, a needle bar drive shaft that is substantially parallel to the transmission shaft is installed inside the tip of the sewing machine arm, and a second transmission belt is stretched between the needle bar drive shaft and the transmission shaft so that the transmission shaft Rotation is transmitted to the needle bar drive shaft by belt transmission. Needle bar is moved up and down by transmitting the rotation of the needle bar drive shaft located in the vicinity of the needle bar and the motion conversion. The main shaft of the sewing machine, the transmission shaft and the needle bar drive shaft project along the outer surface of the sewing machine main body and the sewing machine arm and project from a belt chamber provided independently from the inner side of the sewing machine main body and the sewing machine arm. Is stretched between the protruding portion of the main shaft of the sewing machine and the transmission shaft into the belt chamber, and the second transmission belt is stretched between the protruding portion of the transmission shaft and the needle bar drive shaft into the interior of the belt chamber. Mount . The belt chamber can be opened and closed by a cover plate , facilitates the assembly and replacement of the first and second transmission belts , and removes wear powder generated by the first and second transmission belts along with the rotational transmission. To prevent entry into the sewing machine body and the sewing machine arm.

In the sewing machine according to the second aspect of the present invention, the motion conversion means according to the first aspect includes a crank arm connected to the middle crank of the needle bar drive shaft, and one end of the crank arm in the middle of the needle bar. Each of the other ends is connected, and a needle swinging arm swinging about an axis substantially parallel to the needle bar drive shaft is provided.

  In this invention, a crank and a needle bar provided in the middle of the needle bar drive shaft are connected by a crank arm and a needle swing arm, and the rotation of the needle bar drive shaft is transmitted to the needle swing arm via the crank arm. The needle bar is moved up and down using the swing of the needle swing arm. The crank arm and the needle swing arm are parts commonly used in the needle bar drive mechanism of the sewing machine, and the configuration of the motion conversion means is simplified by sharing the parts.

A sewing machine according to a third aspect of the present invention is attached to an upper decoration shaft supported at two positions spaced apart in the vertical direction inside the sewing machine arm, and a lower end of the upper decoration shaft hanging outside the sewing machine arm. The rotation of the needle bar drive shaft is transmitted between the upper looper that swings in a plane orthogonal to the axis by repetitive rotation of the upper shaft and the upper and lower support portions of the upper shaft. An upper decoration transmission means for repeatedly rotating the decoration shaft is provided.

  In the present invention, a needle bar drive shaft that is installed at the tip of the sewing machine arm and rotates by belt transmission from the sewing machine main shaft is used, and the rotation of the rotation of the needle bar drive shaft is converted so that the upper decoration shaft is located nearby. And the upper decoration looper is operated by repeatedly rotating the upper decoration shaft. With the above-described configuration of the motion conversion means for moving the needle bar up and down, the upper decoration shaft arranged close to the needle bar can be supported at two locations separated vertically, and between these support parts The rotation of the needle bar drive shaft is transmitted, and the repeated rotation of the upper decoration shaft is performed stably.

According to a fourth aspect of the present invention, there is provided a sewing machine according to the third invention, wherein the upper arm transmission means in the third invention projects radially outwardly between the upper and lower support portions of the upper shaft and the swing arm. the sewing machine according to the fifth aspect of the present invention on characterized by comprising a decorative crank arm and the invention for connecting the distal end to the middle of the crank of the needle bar drive shaft, the top covering the crank arm in the fourth invention, The tip of the swing arm and the crank are connected via a ball joint.

  In these inventions, the tip of the swing arm that protrudes radially outward between the upper and lower support portions of the upper shaft and the crank provided in the middle of the needle bar drive shaft are connected by the upper crank arm. Thus, the transmission means for transmitting the rotation of the needle bar drive shaft to the upper decoration shaft is simply configured, and ball joints are used at the connecting portions between both ends of the upper decoration crank arm and the swing arm and the crank. It absorbs the difference of the movement trajectory and makes it move smoothly.

A sewing machine according to a sixth aspect of the present invention is a sewing machine according to the third aspect , wherein the upper decoration transmission means is supported so as to be swingable about an axis substantially parallel to the needle bar drive shaft, and the upper decoration shaft. A swing arm projecting radially outward between the upper and lower support portions, an upper ornament crank arm that connects one end of the upper ornament lever to a midway crank of the needle bar drive shaft, and the upper ornament lever tip of the other end and is characterized in that it comprises a connecting link for connecting the front end of the swing arm, also sewing machine according to the seventh aspect of the present invention, the connecting link of the sixth invention, the swing arm Are connected to a connecting pin projecting parallel to the upper decoration shaft so as to be slidable in the axial length direction, and connected to the other end of the upper decoration lever via a ball joint. And

  In these inventions, the tip of the swing arm projecting radially outward from a part of the upper shaft and the upper crank arm connected at one end to the crank provided in the middle of the needle bar drive shaft. The other end is connected via an upper lever and a connecting link supported so as to be swingable about an axis substantially parallel to the needle bar drive shaft, and the rotation of the needle bar drive shaft is reliably transmitted to the upper shaft. It constitutes a transmission means, and one end of the connecting link is slidably connected to a connecting pin protruding in parallel with the upper decoration shaft at the tip of the swing arm, and the other end of the connecting link is connected to the upper decoration It is connected to the end of the lever via a ball joint to absorb the difference between the movement trajectories of the two and perform a smooth operation.

In the sewing machine according to the first aspect of the present invention, the rotation of the sewing machine main shaft is transmitted to the needle bar drive shaft near the needle bar by belt transmission, and the needle bar is moved up and down by converting the rotation of the needle bar drive shaft. Therefore, the vertical movement of the needle bar can be smoothly performed while suppressing the generation of vibration and sound, and it is possible to cope with an increase in the sewing speed. In addition, the transmission mechanism for the built-in device provided at the tip of the sewing machine arm can be simply configured using a part of the needle bar drive shaft.

In addition, an independent belt chamber is provided along the outer surface of the sewing machine body and the sewing machine arm so that it can be opened and closed by a cover plate inside the sewing machine main body and the sewing machine arm. Since the first and second transmission belts for transmission to the shaft are arranged, the first and second transmission belts can be easily assembled and replaced, and wear is generated due to rotation transmission. There is a risk that powder will not enter the sewing machine main body and the sewing machine arm, and wear powder will adhere to the moving parts provided inside the sewing machine main body and the sewing machine arm, causing problems such as premature wear and seizure of the moving parts. It can be effectively prevented.

In the sewing machine according to the second aspect of the invention, since the motion conversion means for converting the rotation of the needle bar drive shaft into the vertical movement of the needle bar is realized by a general configuration including a crank arm and a needle swing arm, the parts are shared. This simplifies the configuration of the motion conversion means and can reduce the product cost.

In the sewing machine according to the third aspect of the invention, the upper decoration shaft arranged in the vicinity of the needle bar is supported at both ends of the sewing machine arm at the tip portion of the sewing machine arm at two locations separated vertically, and the sewing machine is interposed between these support portions. Since the rotation of the needle bar drive shaft installed at the tip of the arm is transmitted and rotated repeatedly, the operation of the upholstery device provided at the tip of the sewing machine arm is stably performed with a simple configuration. Therefore, it is possible to suppress the generation of vibration and sound and to cope with the increase in the sewing speed.

Further, in the sewing machine according to the fourth and fifth inventions, the upper arm transmission means is configured by directly connecting the swing arm protruding from the upper shaft and the needle bar drive shaft by the upper crank shaft. Further, since the connecting portions at both ends of the upper ornament crank arm are configured to absorb the difference in the movement locus, transmission to the upper ornament device can be stably performed with a simple configuration.

Furthermore, in the sewing machines according to the sixth and seventh inventions, the swing arm and the needle bar drive shaft are connected via a crank arm, an upper decorative lever and a connecting link to constitute an upper decorative transmission means, and the connecting link Since the connecting portions at both ends of the frame are configured to be able to absorb the difference in the movement trajectory, the present invention has an excellent effect such that transmission to the upper decoration device can be performed more reliably.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. FIG. 1 is a perspective view schematically showing the overall configuration of a transmission mechanism for a needle bar in a sewing machine according to the present invention together with the outer shape of the sewing machine. The illustrated sewing machine has a small-diameter cylindrical bed 2 protruding from one side lower part of a sewing machine body 1 standing on the upper surface of a base (not shown), and substantially parallel to the cylindrical bed 2 on the same side upper part. As shown, it is configured as a vertical cylindrical sewing machine having a sewing machine arm 3 protruding therefrom.

  This sewing machine is provided with a feeding device and a looper (not shown) under a needle plate 20 installed at the tip of the cylindrical bed 2 and is attached to the lower end of the needle bar 4 suspended from the tip of the sewing machine arm 3. And a presser foot (not shown) attached to a lower end of a presser bar (not shown) suspended from the tip of the sewing machine arm 3, and a cloth is held between the presser foot and the needle plate 20. Then, a feed toward the proximal end of the cylindrical bed 2 is applied by the operation of the feed device, and sewing is performed by the operation of the needle and looper generated in synchronization with the feed.

  A sewing machine main shaft 5 is installed on the inner lower part of the sewing machine body 1 so that the projecting direction of the cylindrical bed 2 and the sewing machine arm 3 and the axial length direction are substantially orthogonal to each other. A transmission shaft 6 is installed at a height corresponding to the protruding portion of the sewing machine so as to be substantially parallel to the sewing machine main shaft 5. In addition, a needle bar drive shaft 7 is installed near the needle bar 4 in the vicinity of the needle bar 4 so as to be substantially parallel to each of the sewing machine main shaft 5 and the transmission shaft 6. A transmission mechanism for transmitting to the needle bar 4 through the transmission shaft 6 and the needle bar drive shaft 7 and moving the needle attached to the lower end of the needle bar 4 together with the needle bar 4 is configured as follows.

  FIG. 2 is a side view showing the configuration of the transmission mechanism for the needle bar, and FIG. 3 is a plan view similarly viewed from above. One end portion of the sewing machine main shaft 5 protrudes to the outside of one side of the sewing machine main body 1, and the driving belt 51 wound around the driving pulley 50 fitted and fixed to the protruding portion causes the sewing machine main body 1 to be positioned below the sewing machine main body 1. The sewing machine main shaft 5 is connected to the output end of a sewing machine motor (not shown) arranged substantially parallel to the main shaft 5, and the sewing machine main shaft 5 rotates around the shaft by the rotation of the sewing motor transmitted through the driving belt 51 and the driving pulley 50. It is designed to be driven to rotate.

  The other end portion of the sewing machine main shaft 5 protrudes to the outside of the other side of the sewing machine body 1, and a transmission pulley 52 is fitted and fixed to the protruding portion. A transmission shaft 6 installed above the sewing machine main shaft 5 is also protruded on the same side of the sewing machine main body 1, and the first transmission is located at a position aligned with the transmission pulley 52 of the sewing machine main shaft 5 in the axial direction. A pulley 61 and a second transmission pulley 62 are fitted and fixed inside the transmission pulley 61, respectively. Between the first transmission pulley 61 and the transmission pulley 52 of the sewing machine main shaft 5, the first transmission pulley 61 is fixed. A transmission belt 60 is stretched. As shown in FIG. 3, a pulley 63 for manual rotation is fitted and fixed to the protruding end of the transmission shaft 6, but in the side view shown in FIG. The pulley 63 for use is not shown.

  The needle bar drive shaft 7 installed at the tip of the sewing machine arm 3 is also projected to the outside on the same side of the sewing machine arm 3, and this projecting portion is connected to the second transmission pulley 62 of the transmission shaft 6 in the axial direction. A transmission pulley 71 is fitted and fixed at a matching position, and a second transmission belt 70 is stretched between the transmission pulley 71 and the second transmission pulley 62 of the transmission shaft 6.

  It is also possible to further extend the needle bar drive shaft 7 from the fitting portion of the transmission pulley 71, and attach a pulley 63 for manual rotation to this extended end. Similarly, the sewing machine main shaft 5 is fitted to the transmission pulley 52. It is also possible to extend further from the section and attach a hand-pulling pulley 63 to this extended end.

  FIG. 2 shows a side view of the side where the first and second transmission belts 60 and 70 are stretched. As shown in the figure, a belt chamber 10 is integrally formed on the side surfaces of the sewing machine body 1 and the sewing machine arm 3 on the same side, extending vertically along the sewing machine body 1, bent at the upper part, and extending toward the tip of the sewing machine arm 3. The transmission pulley 52 of the sewing machine main shaft 5, the first and second transmission pulleys 61 and 62 of the transmission shaft 6, and the transmission pulley 71 of the needle bar drive shaft 7 are wound around them. The second transmission belts 60 and 70 are housed in the belt chamber 10.

  With the configuration described above, the rotation of the sewing machine main shaft 5 is transmitted to the transmission shaft 6 via the first transmission belt 60 and further transmitted to the needle bar drive shaft 7 via the second transmission belt 70. 6 and the needle bar drive shaft 7 rotate fully around their respective axes. Since this rotational transmission is performed by belt transmission by the transmission belts 60 and 70, it is possible to perform transmission at high speed while keeping the vibration and sound generated by the transmission at a low level. The first and second transmission belts 60 and 70 have a large number of teeth arranged in parallel on their inner surfaces, and these teeth are connected to the transmission pulley 52, the first and second transmission pulleys 61 and 62, and the transmission pulley 71. It is desirable to make it a timing belt that can mesh with teeth provided on the outer periphery of the belt and transmit power without slipping.

  Here, the first and second transmission belts 60 and 70 are belts opened on the side surfaces of the sewing machine body 1 and the sewing machine arm 3 together with the transmission pulley 52, the first and second transmission pulleys 61 and 62, and the transmission pulley 71. Since it is arranged in the chamber 10, operations such as adjustment of the rotational position between the shafts during assembly and replacement of the transmission belts 60 and 70 are performed outside the sewing machine body 1 and the sewing machine arm 3 through the opening of the belt chamber 10. Can be easily performed. The rotation position is adjusted by releasing any one of the transmission pulley 52, the first and second transmission pulleys 61 and 62, and the transmission pulley 71 and moving the sewing machine main shaft 5, the transmission shaft 6 or the needle bar drive shaft 7 on the circumference. This is done by changing the position and fixing again.

  In addition, since the rotational transmission by the transmission belts 60 and 70 generally does not require oil lubrication, the belt chamber 10 that houses the transmission belts 60 and 70 is a chamber independent from the inside of the sewing machine body 1 and the sewing machine arm 3. It is said. As a result, the friction powder generated by the rotational transmission between the transmission pulleys 52 and 61 and the transmission belt 60 and between the transmission pulleys 62 and 71 and the transmission belt 70 is generated inside the sewing machine body 1 and the sewing machine arm 3. It is possible to effectively prevent the possibility of causing inconveniences such as premature wear and seizure in the movable part that is configured to enter the inside. Needless to say, the opening of the belt chamber 10 is closed by a cover plate (not shown) when the sewing machine is used.

  The needle bar drive shaft 7 that is fully rotated by the above transmission is extended inside the sewing machine arm 3, and is connected to the needle bar 4 by the motion conversion means 8 including the crank arm 80 and the needle swing arm 81. FIG. 4 is an enlarged cross-sectional side view of a main part showing the configuration of the motion converting means 8.

  As shown in the drawing, a crank 72 having a predetermined eccentric amount is integrally formed in the middle of the needle bar drive shaft 7, and a base end portion of a crank arm 80 is connected to the crank 72. The needle swing arm 81 is pivotally supported by a support shaft 82 that is substantially parallel to the needle bar drive shaft 7, can swing around the support shaft 82, and extends toward the needle bar drive shaft 7. One end of the needle swing arm 81 is connected to the tip of the crank arm 80 via a ball joint 83, and the other end of the needle swing arm 81 extending toward the needle bar 4 holds the middle of the needle bar 4. The needle bar holder 40 is connected via a short link 84.

  With the above configuration, the rotation of the needle bar drive shaft 7 is transmitted to the needle swing arm 81 via the crank arm 80 connected to the crank 72. The needle swing arm 81 is driven by the needle bar with the support shaft 82 as the pivot. The vertical movement of the other end of the needle swing arm 81 accompanying this swing is transmitted to the needle bar 4 via the link 84 and the needle bar holder 40, The needle bar 4 and a needle (not shown) attached to the lower end of the needle bar 4 can be moved up and down. In FIG. 4, the needle swing arm 81 whose connection side with the needle bar 4 is at the lowest position is indicated by a solid line, and the needle swing arm 81 at the same uppermost position is indicated by a two-dot chain line. Is performed in response to the swing of the needle swing arm 81 generated between these positions.

  The motion converting means 8 for moving the needle bar 4 up and down in this way includes a short crank arm 80 and a needle swinging arm 81 between the needle bar driving shaft 7 arranged close to the needle bar 4. The reaction force accompanying the operation of the crank arm 80 and the needle swing arm 81 is small. Therefore, the vibration and sound generated by this reaction force can be suppressed to a low level, and the operation speed can be increased without increasing the vibration and sound, and the sewing speed can be increased.

  Using the sewing machine according to the present invention configured as described above and a conventional sewing machine provided with the needle bar drive mechanism disclosed in Patent Document 1, a test was performed to compare the degree of vibration and sound generated during operation of both. As a result, in the conventional sewing machine, the upper limit rotational speed of the sewing machine main shaft 5 is about 3500 rpm under the condition that the level of driving vibration and sound is suppressed to a level that does not cause any practical problem. In sewing machines, it has been confirmed that the maximum speed under the same conditions can be 5000 rpm or more.

  The crank arm 80 and the needle swing arm 81 constituting the motion converting means 8 are parts widely used in the needle bar drive mechanisms of many sewing machines, and the parts can be shared with other types of sewing machines.

  Further, in the sewing machine according to the present invention, the needle bar drive shaft 7 that is fully rotated by the transmission from the sewing machine main shaft 5 is present at the tip of the sewing machine arm 3. The transmission means can be simply configured near the tip of the sewing machine arm 3 using the needle bar drive shaft 7 as a drive source.

  FIG. 5 is a side view showing the configuration of the upper decoration transmission means for transmission to the upper decoration device, FIG. 6 is a plan view similarly viewed from above, and FIG. 7 is an external perspective view of the main part.

  The upper decoration device includes an upper decoration shaft 9 that is supported inside the sewing machine arm 3 with its axis centered up and down, and an upper decoration looper 90 that is attached to the lower end of the upper decoration shaft 9. The upper decoration shaft 9 is supported by bearing bushes 91 and 92 fixed to the upper and lower walls of the sewing machine arm 3 so as to be rotatable about the shaft, and is indicated by a needle bar drive shaft 7 and a two-dot chain line in FIG. It is arranged between the needle bar 4.

  The upper decoration looper 90 is attached to the lower end of the upper decoration shaft 9 suspended below the sewing machine arm 3 via a looper base 93, and the tip of the upper decoration looper 90 bent in a bowl shape is attached to the upper decoration shaft 9 Is extended to the front of the needle bar 4 in a plane substantially perpendicular to the needle bar 4. The upper decoration looper 90 attached in this way swings with the looper base 93 in accordance with the repeated rotation of the upper decoration shaft 9, and an upper decoration thread (not shown) is attached to the lower end of the needle bar 4 by this swinging. A known operation of supplying the sewing position with the needle is performed.

  The upper ornament transmission means 9a is configured to transmit the rotation of the needle bar drive shaft 7 to the upper ornament shaft 9, and to rotate the upper ornament shaft 9 repeatedly. The upper ornament lever 90a, the swing arm 91a, the upper ornament A crank arm 92a and a connecting link 93a are provided. The upholstery lever 90a has a dogleg-shaped bent shape, and supports the bent portion by a support shaft 94a protruding substantially parallel to the needle bar drive shaft 7 on the side wall of the sewing machine arm 3. Between the rod drive shaft 7 and the upper decoration shaft 9, the support shaft 94a is pivotally mounted as a pivot.

  The upper crank arm 92a is connected to the upper crank 73 integrally formed with a predetermined amount of eccentricity in the middle part of the needle bar drive shaft 7, and is inclined toward the upper decorative shaft 9 side. The tip of the upper decorative crank arm 92a extending upward is connected to one end of an upper decorative lever 90a extending obliquely upward toward the needle bar drive shaft 7 side. As shown in FIG. 5, the position of this connection is adjustable along a long hole 95a provided in the upper lever 90a.

  With the above configuration, the rotation of the needle bar drive shaft 7 is transmitted to the upper ornament lever 90a via the upper ornament crank arm 92a connected to the upper ornament crank 73. The upper ornament lever 90a has the support shaft 94a as the pivot. The needle bar drive shaft 7 is swung with one rotation as one cycle. This swing angle can be changed by adjusting the connecting position made along the long hole 95a as described above. 6 is arranged separately on one side of the crank 72 for transmission to the needle bar 4, but the upper ornament crank 73 and the crank 72 are integrally arranged in parallel. It is also possible to do.

  The swing arm 91a is located between the upper and lower support bushes 91 and 92 and holds the middle part of the upper decoration shaft 9, and is attached so as to protrude outward in the radial direction as shown in FIGS. The tip of the swing arm 91a attached in this way is connected to the other end of the upper decoration lever 90a extending downward via a connection link 93a.

  As shown in FIG. 5, a connecting pin 96a is provided at the front end of the swing arm 91a so as to extend downward in parallel with the upper decoration shaft 9. The swing arm 91a and the connection link 93a are connected to each other. The bracket provided at the same end of the connecting link 93a is fitted to the connecting pin 96a so as to be slidable in the axial direction. Further, a connecting pin 97a is projected from the other end of the upper decoration lever 90a so as to be substantially parallel to the support shaft 94a and the needle bar drive shaft 7, and the connection between the upper decoration lever 90a and the connection link 93a is as follows. As shown in FIG. 7, it is made through a ball joint formed by holding a sphere integrally connected to the tip of the connecting pin 97a by a bracket provided at the same end of the connecting link 93a.

  The swing of the top decoration lever 90a generated as described above is transmitted to the swing arm 91a via the connecting link 93a, and the top cover shaft 9 to which the swing arm 91a is attached is connected to the top cover lever 90a. The thread is supplied by the upper looper 90 which is repeatedly rotated at an angle corresponding to the swing angle of the upper loop and attached to the lower end of the upper block 9.

  At this time, the swing of the lower end of the upper decoration lever 90a with the support shaft 94a as a pivot occurs with a vertical displacement, and the swing locus of the swing arm 91a generated in a plane perpendicular to the upper decoration shaft 9 However, the connecting link 93a that connects the upper lever 90a and the swing arm 91a as described above is moved in the vertical direction by sliding along the connecting pin 96a with respect to the swing arm 91a. And can be tilted in an appropriate direction by the action of the ball joint provided at the connecting portion with respect to the upper decoration lever 90a. The swing of the decoration lever 90a is smoothly and reliably transmitted to the swing arm 91a, and the operation of the upper decoration looper 90 by the repeated rotation of the upper decoration shaft 9 can be performed reliably.

  Further, since the upper decoration shaft 9 is supported by the support bushes 91 and 92 above and below the mounting position of the swing arm 91a, the upper decoration shaft 9 is caused by the pushing and pulling force transmitted to the tip of the swing arm 91a by the connecting link 93a. The tilting of the upper looper 90 can be set with high accuracy. The operation position is set by changing the fixed position of the looper base 93 at the lower end of the upper decoration shaft 9 in the axial length direction and the circumferential direction of the upper decoration shaft 9, and at the set operation position. As described above, the operation stroke of the upper decorative looper 90 is changed by adjusting the connecting position of the upper decorative crank arm 92a and the upper decorative lever 90a.

  According to the upper ornament transmission means 9a configured as described above, the upper ornament device incorporated in the distal end portion of the sewing machine arm 3 can be reliably and smoothly operated by the transmission from the needle bar drive shaft 7. Further, the upper decorative lever 90a, the swing arm 91a, the upper decorative crank arm 92a, and the connecting link 93a constituting the upper decorative transmission means 9a are both small-bulk parts, and the reaction force associated with these operations is small. It is possible to cope with an increase in operation speed without generating significant vibration and sound. Further, the upper decoration shaft 9 can support both upper and lower portions without interfering with the above-described motion converting means 8 for moving the needle bar 4 up and down, and the upper decoration transmission means is provided between these support portions. Since the transmission by 9a is performed, the operation of the upper looper 90 can be performed with high accuracy.

  FIG. 8 is an external perspective view showing another embodiment of the upper decoration transmission means, and FIG. 9 is an exploded perspective view of the same. The upper decoration transmission means 9b shown in this figure, like the upper decoration transmission means 9a shown in FIGS. 5 to 7, transmits the rotation of the needle bar drive shaft 7 to the upper decoration shaft 9, and rotates the upper decoration shaft 9 repeatedly. In order to achieve this, an upper decoration crank arm 90b and a swing arm 91b are provided. The configuration of the upper decoration device including the upper decoration shaft 9, the upper decoration looper 90, and the like is the same as that of the embodiment shown in FIGS. 5 to 7, and the same reference numerals are assigned to the corresponding members in detail. Description is omitted.

  The swing arm 91b of the upper ornament transmission means 9b is attached so as to hold the middle portion of the upper ornament shaft 9 between the upper and lower support bushes 91 and 92 and project outward in the radial direction. The upper cover crank arm 90b is connected to the upper cover crank 74 integrally formed with a predetermined amount of eccentricity in the middle part of the needle bar drive shaft 7, and is connected to the upper cover shaft 9 side. The tip of the decorative crank arm 90b is connected to the tip of the swing arm 91b.

  As shown in FIG. 9, the upper crank 74 includes a crank pin 75 processed into a spherical surface, and a connecting pin 92b processed into a spherical surface is integrally formed at the tip of the swing arm 91b. On the other hand, a large bracket 93b having a spherical inner surface corresponding to the crankpin 75 is provided at the base end portion of the upper crank arm 90b, and a small bracket 94b having a spherical inner surface corresponding to the connecting pin 92b is provided at the distal end portion. As shown in FIG. 8, the upper crank arm 90b and the upper crank 73 are connected to each other through a ball joint formed by holding a crank pin 75 by a large bracket 93b. The upper crank arm 90b and the swing arm 91b are connected via a ball joint formed by holding a connecting pin 92b by a small bracket 94b.

  With the above configuration, the rotation of the needle bar drive shaft 7 is directly transmitted to the swing arm 91b via the top crank arm 90b connected to the top crank 74, and the top of the swing arm 91b is attached. The decoration shaft 9 is repeatedly rotated with one rotation of the needle bar drive shaft 7 as one cycle, and a thread supply operation is performed by an upper decoration looper 90 attached to the lower end of the upper decoration shaft 9.

  At this time, the swing arm 91b swings within a predetermined angle range with the upper decoration shaft 9 as a pivot, and the tip of the swing arm 91b is located within a predetermined angle range on the circumference around the upper decoration shaft 9. Move back and forth. On the other hand, the crankpin 75 of the upper crank 74 moves circularly along a predetermined circumference centering on the needle bar drive shaft 7. The upper crank arm 90b that connects the swing arm 91b and the crank pin 75 can be tilted in an appropriate direction by the action of ball joints provided at both ends. It acts to absorb the above-described difference in motion locus with the pin 75. Thereby, the rotation of the needle bar drive shaft 7 is smoothly and reliably transmitted to the swing arm 91b, and the operation of the upper looper 90 by the repeated rotation of the upper cover shaft 9 can be performed reliably.

  The upper crank 74 includes an adjustment screw 76 for adjusting the eccentric amount of the crankpin 75 and fixing screws 77 and 77 for fixing the adjustment position. Can be changed freely by changing the eccentric amount of the crank pin 75 by operating the adjusting screw 76 and tightening and fixing the fixing screws 77 and 77.

  According to the upper decoration transmission means 9b configured as described above, the upper decoration device incorporated in the distal end portion of the sewing machine arm 3 can be reliably and smoothly operated by the transmission from the needle bar drive shaft 7. Further, the upper decoration shaft 9 can support both upper and lower portions without interfering with the motion converting means 8 for moving the needle bar 4 up and down, and the upper decoration transmission means is provided between these support portions. Since the transmission by 9b is performed, the operation of the upper looper 90 can be performed with high accuracy.

  Furthermore, the upper transmission means 9b has a simple structure including only the upper crank arm 90b and the swing arm 91b as substantial components, and the sewing machine arm 3 does not interfere with the motion conversion means 8. In addition, the upper crank arm 90b and the swing arm 91b are both small parts, and the reaction force associated with these operations is small. It is possible to cope with an increase in operating speed without generating sound.

  In the above embodiment, the vertical cylindrical shape is configured such that the fabric on the needle plate 20 installed at the distal end portion of the cylindrical bed 2 is sewn while feeding toward the proximal end side of the cylindrical bed 2. However, the present invention includes a sewing machine main shaft 5 orthogonal to the protruding direction of the sewing machine arm 3, and a needle bar provided at the tip of the sewing machine arm 3 by transmission from the sewing machine main shaft 5. The sewing machine can be applied to all sewing machines that are configured to move 4 up and down.

1 is a perspective view schematically showing an overall configuration of a transmission mechanism to a needle bar in a sewing machine according to the present invention, together with the outer shape of the sewing machine. It is a side view which shows the structure of the transmission mechanism to a needle bar. It is the top view seen from the upper part of the transmission mechanism to a needle bar. It is a principal part expanded sectional side view which shows the structure of a motion conversion means. It is a side view of the upper decoration transmission means for transmission to an upper decoration apparatus. It is the top view seen from the upper part of the upper decoration transmission means for transmission to an upper decoration apparatus. It is an external appearance perspective view of the principal part of the upper decoration transmission means for transmission to an upper decoration apparatus. It is an external appearance perspective view which shows other embodiment of a top ornament transmission means. It is a disassembled perspective view which shows other embodiment of a top ornament transmission means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sewing machine main body 2 Cylindrical bed 3 Sewing arm 4 Needle bar 5 Sewing machine main shaft 6 Transmission shaft 7 Needle bar drive shaft 8 Motion conversion means 9 Top decoration shaft
9a, 9b Appearance transmission means
60 First transmission belt
70 Second transmission belt
80 crank arms
81 Needle swing arm
90 Upper looper
90a Top lever
91a Swing arm
92a Top crank arm
93a Link
90b swing arm
91b Top crank arm

Claims (7)

A sewing machine main body incorporating a sewing machine main shaft at the lower part, a sewing machine arm projecting from the upper part of the sewing machine main body in a direction substantially perpendicular to the sewing machine main shaft, and a needle bar supported downwardly at the tip of the sewing machine arm; In the sewing machine configured to vertically move the needle attached to the hanging lower end of the needle bar by transmission from the sewing machine main shaft,
A transmission shaft installed on the inner upper part of the sewing machine body so as to be substantially parallel to the sewing machine main shaft, and stretched between the transmission shaft and the sewing machine main shaft, and transmits rotation of the sewing machine main shaft to the transmission shaft. A first transmission belt;
A needle bar drive shaft erected in the vicinity of the needle bar inside the front end of the sewing machine arm so as to be substantially parallel to the sewing machine main shaft and the transmission shaft;
A second transmission belt stretched between the needle bar drive shaft and the transmission shaft, and transmitting the rotation of the transmission shaft to the needle bar drive shaft;
Movement conversion means for converting rotation of the needle bar drive shaft into vertical movement of the needle bar;
A belt chamber that extends vertically along the outer surface of the sewing machine main body, is bent at the upper portion, and extends toward the tip along the outer surface of the sewing machine arm is provided independently from the inner side of the sewing machine main body and the sewing machine arm. The first transmission belt is stretched between transmission pulleys fitted into the sewing machine main shaft and the transmission end of the transmission shaft into the belt chamber, and the second transmission belt is Ri stretched Citea between the needle bar drive shaft and the transmission pulley which are respectively fitted to the protruding end of the transmission shaft to the belt chamber, the belt chamber, tare Rukoto it possible to open and close by cover plate Characteristic sewing machine. The motion conversion means includes
A crank arm connected to a midway crank of the needle bar drive shaft;
2. The needle arm according to claim 1, further comprising: a needle swinging arm that has one end connected to the crank arm and the other end connected to the middle of the needle bar, and swings about an axis substantially parallel to the needle bar drive shaft. sewing machine. An upper decoration shaft supported at two locations spaced apart vertically inside the sewing machine arm;
An upper looper that is attached to the lower end of the upper decoration shaft that is suspended outside the sewing machine arm, and that swings in a plane perpendicular to the axis by repetitive rotation of the upper decoration shaft;
The sewing machine according to claim 1 or 2, further comprising upper decoration transmission means for transmitting rotation of the needle bar drive shaft between upper and lower support portions of the upper decoration shaft and repeatedly rotating the upper decoration shaft. The upper decoration transmission means is:
A swing arm projecting radially outward between the upper and lower support portions of the upper decoration shaft;
The sewing machine according to claim 3, further comprising: an upper crank arm that connects a tip of the swing arm to a midway crank of the needle bar drive shaft.   The sewing machine according to claim 4, wherein the upper crank arm is connected to a tip of the swing arm and the crank via a ball joint. The upper decoration transmission means is:
An upper decoration lever supported so as to be swingable about an axis substantially parallel to the needle bar drive shaft;
A swing arm projecting radially outward between the upper and lower support portions of the upper decoration shaft;
An upper crank arm that connects one end of the upper decorative lever to a midway crank of the needle bar drive shaft;
The sewing machine according to claim 3, further comprising: a connecting link that connects the other end of the upper decoration lever and a tip of the swing arm.   The connecting link is slidably connected in the axial length direction to a connecting pin projecting from the tip of the swing arm so as to be parallel to the upper decorative shaft, and a ball is connected to the other end of the upper decorative lever. The sewing machine according to claim 6, wherein the sewing machine is connected through a joint.

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