Patent Description:
In the technical field related to sewing machines, a sewing machine referred to as the so-called lock-stitch sewing machine, as disclosed in Patent Document <NUM>, is known.

[Patent Document <NUM>] <CIT>
<CIT> discloses a sewing machine having a belt continuously moving a material being stitched, and having a developed cam moving a needle transversely of its normal reciprocation, and a cooperating looper moving in the direction of movement of the material and cooperating with the transversely moving needle to effect stitching. <CIT> discloses a sewing machine for sewing continuously moving materials. <CIT> discloses a sewing machine for sewing plastic- or metal web. <CIT> discloses a differential feed sewing machine for execution of a sewing process.

In the sewing machine, when a sewing object is to be sewn, for example, there is a specification of feeding the sewing object in a state in which a sewing needle is withdrawn from the sewing object. In addition, in the sewing machine, when sewing is performed in a state in which sewing objects overlap, there is a specification of feeding the sewing objects together with the sewing needle, so that upper and lower sewing objects are not shifted. In the case of switching the two specifications, the task is difficult as extensive recombination is required.

The present invention is provided by the appended claims. The following disclosure serves a better understanding of the present invention. An objective of the disclosure is to provide a sewing machine able to easily switch the specification of feeding the sewing object.

An aspect of the disclosure provides a sewing machine. The sewing machine includes: a sewing needle, held by a needle bar and holding an upper thread to move reciprocally; a shuttle, holding a bobbin which is accommodated in a bobbin case and in which a lower thread is wound, and cooperating with the sewing needle to form a seam; a pressing member, pressing a sewing object disposed at a sewing position immediately below the sewing needle; a feed mechanism, in which endless feed belts feeding the sewing object disposed at the sewing position from the sewing position along a first direction are disposed on two sides with respect to the sewing position in a second direction orthogonal to the first direction, and in which a belt drive part is provided; a needle drive part, provided separately from the belt drive part, and moving the sewing needle in the first direction; and a control part, exerting control so that the belt drive part and the needle drive part are able to operate independently.

According to the disclosure, the specifications of feeding the sewing object can be switched easily.

Embodiments according to the disclosure will be described below with reference to the drawings. However, the disclosure shall not be limited to the embodiments.

A sewing machine <NUM> according to the embodiment is described. In the embodiment, the positional relationship of each component is described based on a local coordinate system defined in the sewing machine <NUM>. The local coordinate system is defined by an XYZ orthogonal coordinate system. A direction parallel to X-axis in a predetermined plane is defined as the X-axis direction (second direction). A direction parallel to Y-axis within a predetermined plane perpendicular to X-axis is defined as the Y-axis direction (first direction). A direction parallel to Z-axis perpendicular to the predetermined planes is defined as the Z-axis direction. A direction of rotation about X-axis is defined as the θX direction.

<FIG> is a schematic perspective view illustrating the sewing machine <NUM> according to an embodiment. As shown in <FIG>, the sewing machine <NUM> includes a sewing machine head <NUM>, a needle bar <NUM>, a take-up <NUM>, a thread tensioner <NUM>, a needle plate <NUM>, a pressing member <NUM>, a shuttle <NUM>, a motor <NUM>, a feed mechanism <NUM>, a needle drive part <NUM>, and a control part <NUM>.

The needle bar <NUM> holds a sewing needle <NUM> and moves reciprocally in the Z-axis direction. The needle bar <NUM> holds the sewing needle <NUM> so that the sewing needle <NUM> is parallel to Z-axis. The needle bar <NUM> is supported by the sewing machine head <NUM>. The needle bar <NUM> is disposed above the needle plate <NUM>, and is able to face the surface of a sewing object S. An upper thread UT is threaded onto the sewing needle <NUM>. The sewing needle <NUM> has a thread passing hole through which the upper thread UP passes. The sewing needle <NUM> holds the upper thread UT by using an inner surface of the thread passing hole. Through the reciprocal movement of the needle bar <NUM> in the Z-axis direction, the sewing needle <NUM> reciprocally moves in the Z-axis direction in a state of holding the upper thread UT.

The take-up <NUM> supplies the upper thread UT to the sewing needle <NUM>. The take-up <NUM> is supported by the sewing machine head <NUM>. The take-up <NUM> has a take-up hole through which the upper thread UT passes. The take-up <NUM> holds the upper thread UT by using an inner surface of the take-up hole. The take-up <NUM> moves reciprocally in the Z-axis direction in a state of holding the upper thread UT. The take-up <NUM> is linked with the needle bar <NUM> to move reciprocally. Through the reciprocal movement in the Z-axis direction, the take-up <NUM> lets out or pulls up the upper thread <NUM>.

The thread tensioner (upper thread tension adjustment mechanism) <NUM> applies tension to the upper thread UT. The upper thread UT is supplied to the thread tensioner <NUM> from a thread supply source. On a passage that the upper thread UT passes through, the take-up <NUM> is disposed between the sewing needle <NUM> and the thread tensioner <NUM>. The thread tensioner <NUM> adjusts the tension of the upper thread UT supplied to the sewing needle <NUM> via the take-up <NUM>.

The needle plate <NUM> supports the sewing object S. The sewing needle <NUM> held by the needle bar <NUM> and the needle plate <NUM> are opposite to each other. The needle plate <NUM> has a needle hole that the sewing needle <NUM> is able to pass through. The sewing needle <NUM> that penetrates through the sewing object S supported by the needle plate <NUM> passes through the needle hole.

The pressing member <NUM> presses the sewing object S from the above. The pressing member <NUM> is supported by the sewing machine head <NUM>. The pressing member <NUM> is disposed above the needle plate <NUM>, and holds the sewing object S with respect to the needle plate <NUM>.

The shuttle <NUM> holds a bobbin accommodated in a bobbin case. The shuttle <NUM> is disposed below the needle plate <NUM>. The shuttle <NUM> rotates in the θX direction. The shuttle <NUM> is linked with the needle bar <NUM> to rotate. The shuttle <NUM> supplies a lower thread LT. The shuttle <NUM> scoops up the upper thread UT from the sewing needle <NUM> that penetrates through the sewing object S supported by the needle plate <NUM> and passes through the needle hole of the needle plate <NUM>.

The motor <NUM> generates power. The motor <NUM> has a stator supported by the sewing machine head <NUM> and a rotor rotatably supported by the stator. Through the rotation of the rotor, the motor <NUM> generates power. The power generated by the motor <NUM> is transmitted to the needle rod <NUM>, the take-up <NUM>, and the shuttle <NUM>, respectively, via a power transmission mechanism (not shown). The needle rod <NUM>, the take-up <NUM>, and the shuttle <NUM> are linked. By transmitting the power generated by the motor <NUM> to the needle rod <NUM>, the needle rod <NUM> and the sewing needle <NUM> held by the needle rod <NUM> move reciprocally in the Z-axis direction. By transmitting the power generated by the motor <NUM> to the take-up <NUM>, the take-up <NUM> is linked with the needle rod <NUM> to move reciprocally in the Z-axis direction. By transmitting the power generated by the motor <NUM> to the shuttle <NUM>, the shuttle <NUM> is linked with the needle rod <NUM> and the take-up <NUM> to rotate in the θX direction. The sewing machine <NUM> sews the sewing object S through the cooperation of the sewing needle <NUM> held by the needle bar <NUM> and the shuttle <NUM>.

The feed mechanism <NUM> delivers the sewing object S from a sewing position PS toward the Y-axis direction. In the embodiment, the feed mechanism <NUM> is disposed lower than the sewing object S disposed at the sewing position PS. A feed mechanism disposed higher than the sewing object S disposed at the sewing position PS may also be provided separately. The feed mechanism <NUM> has feed belts <NUM> and a belt drive part <NUM>.

<FIG> is a view illustrating an example of the feeding mechanism <NUM>. As shown in <FIG>, the feed belts <NUM> contact a back surface Sb of the sewing object S. The feed belt <NUM> is in a ring shape (endless). The feed belts <NUM> are disposed on two sides in the X-axis direction with respect to the sewing position PS. On each of the two sides in the X-axis direction with respect to the sewing position PS, two feed belts <NUM> are disposed. That is, a total of four feed belts <NUM> are disposed. In the following, the two feed belts <NUM> disposed on a side (-X side) in the X-axis direction with respect to the sewing position PS are represented as feed belts 21A, and the two feed belts <NUM> disposed on the other side (+X side) in the X-axis direction with respect to the sewing position PS are represented as feed belts 21B.

The belt drive part <NUM> independently drives the feed belts 21A on the -X side with respect to the sewing position and the feed belts 21B on the +X side with respect to the sewing position PS. The belt driving part <NUM> has a drive system 22A that drives the feed belts 21A on the -X side of the sewing position PS and a drive system 22B that drives the feed belts 21B on the +X side of the sewing position PS. The drive system 22A has a motor 23A and a sprocket 24A. The drive system 22B has a motor 23B and a sprocket 24B.

When the motors 23A, 23B operate, the belts 21A supported by the sprocket 24A and the belts 21B supported by the sprocket 24B rotate in the Y-axis direction. Through the rotation of the belts 21A, 21B, the sewing object S is delivered in the Y-axis direction.

Referring to <FIG> again, the needle drive part <NUM> moves the sewing needle <NUM> in the Y-axis direction. The needle drive part <NUM> has a motor <NUM> and a transmission mechanism <NUM>. The motor <NUM> is provided separately from the motors 23A, 23B of the belt driving part <NUM>. The transmission mechanism <NUM> transmits a drive force generated by the motor <NUM> to the sewing needle <NUM>. The transmission mechanism <NUM> moves the sewing needle <NUM> in the Y-axis direction through a shaft and a timing belt not shown herein. The motor <NUM> and the transmission mechanism <NUM> are provided inside the sewing machine head <NUM>.

The control part <NUM> collectively controls the operation of the sewing machine <NUM>. The control part <NUM> has a processing part <NUM> and a storage part <NUM>. The processing part <NUM> performs various information processing. The processing part <NUM> includes a processor, such as a central processing unit (CPU), and a memory, such as a read only memory (ROM), a random access memory (RAM).

The processing part <NUM> has a lifting drive control part <NUM>, a determination part <NUM>, a belt drive control part <NUM>, and a needle drive control part <NUM>.

The lifting drive control part <NUM> controls the movement of the sewing needle <NUM> in the Z-axis direction by controlling the rotation of the motor <NUM>.

The determination part <NUM> determines the mode of feeding the sewing object S. The determination part <NUM> determines, for example, whether a belt feed mode is set or a needle feed mode is set. The belt feed mode is a mode that feeds the sewing object S in the Y-axis direction in a state in which the sewing needle <NUM> is withdrawn from the sewing object S. The needle feed mode is a mode that feeds the sewing object S and the sewing needle <NUM> in the Y-axis direction in a state in which the sewing needle <NUM> is stuck in the sewing object S. For example, in a case where sewing is performed in a state in which multiple sewing objects S overlap, the needle feed mode can suppress upper and lower objects in the upper-lower direction from being shifted in the horizontal direction.

The belt drive control part <NUM> controls the movement of the feed belts 21A, 21B toward the Y-axis direction by controlling the rotation of the motors 23A, 23B of the belt drive part <NUM>. In the case where the transport mode of the sewing object S is set to the belt feed mode, the belt drive control part <NUM> controls the belt drive part <NUM>, so that the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the feed belts <NUM> move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. In addition, in the case where the transport mode of the sewing object S is set to the needle feed mode, the belt drive control part <NUM> controls the belt drive part <NUM>, so that the feed belts <NUM> moves the sewing needle <NUM> in the Y-axis direction by a predetermined distance during the period in which the sewing needle <NUM> is stuck to the sewing object S and the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S.

The needle drive control part <NUM> controls the movement of the sewing needle <NUM> in the Y-axis direction by controlling the rotation of the motor <NUM> of the needle drive part <NUM>. In the case where the transport mode of the sewing object S is set to the belt feed mode, the needle drive control part <NUM> controls the needle drive part <NUM> so that the sewing needle <NUM> does not move in the Y-axis direction. In the case where the transport mode of the sewing object S is set to the needle feed mode, the needle drive control part <NUM> controls the needle drive part <NUM>, so that the sewing needle <NUM> moves synchronously with the feed belts <NUM> by the predetermined distance in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S and the sewing needle <NUM> does not move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S.

The storage part <NUM> stores information such as various programs, data. The storage part <NUM> includes a storage such as a hard disk drive (HDD), a solid state drive (SDD).

With the processor reading various programs and expanding the programs in the memory in the processing part <NUM>, information processing corresponding to the functions of the respective parts is executed in the control part <NUM>. Examples of the various programs may include programs stored in the storage part <NUM>, programs recorded in an external recording medium, etc. The control part <NUM> serves as an information processing device (computer) executing various information processing. An information processing device other than the control part <NUM> may execute the various programs, or the control unit <NUM> and other information processing devices other than the control unit <NUM> may cooperate to execute the various programs.

In the following, the operation of the sewing machine <NUM> with such configuration is described. An operator places the sewing object S at the sewing position PS, and the sewing object S is arranged to be pressed by the pressing member <NUM>. In such state, when the operator performs an operation to start sewing, the lifting drive control part <NUM> of the control part <NUM> controls the rotation of the motor <NUM> so that the sewing needle <NUM> reciprocally moves in the Z-axis direction. In addition, the belt drive control part <NUM> controls the feed amounts of the feed belts 21A, 21B by controlling the rotation of the motors 23A, 23B of the belt drive part <NUM>. In addition, the needle drive control part <NUM> controls the movement of the sewing needle <NUM> in the Y-axis direction by controlling the rotation of the motor <NUM> of the needle drive part <NUM>.

By operating an operation panel (not shown) provided in the sewing machine <NUM>, for example, the operator can set the mode of feeding the sewing object S to the belt feed mode or the needle feed mode. In addition, the operator can switch the setting as appropriate by using the operation panel. In the control part <NUM>, the determination part <NUM> determines the mode of feeding the sewing object S.

In the case where the determination part <NUM> determines that the belt feed mode is set, the belt drive control part <NUM> controls the belt drive part <NUM>, so that the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the feed belts <NUM> move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. In addition, the needle drive control part <NUM> controls the needle drive part <NUM> so that the sewing needle <NUM> does not move in the Y-axis direction.

<FIG> is a view illustrating an example of an operation in the belt feed mode. As shown in <FIG>, through the control of the belt drive control part <NUM> and the needle drive control part <NUM>, in the belt feed mode, the sewing object S is not fed in the Y-axis direction during a period ST1 in which the sewing needle <NUM> is stuck to the sewing object S. In addition, during a period ST2 in which the sewing needle <NUM> is withdrawn from the sewing object S, the sewing object S is fed in the Y-axis direction by the feed belts <NUM>.

<FIG> is a view illustrating an example of an operation in the need feed mode. As shown in <FIG>, through the control of the belt drive control part <NUM> and the needle drive control part <NUM>, in the needle feed mode, the sewing object S is not fed in the Y-axis direction during a period ST3 in which the sewing needle <NUM> is withdrawn from the sewing object S. In addition, during a period ST4 in which the sewing needle <NUM> is stuck to the sewing object S, the sewing needle <NUM> and the feed belts <NUM> move synchronously in the Y-axis direction, and the sewing object S is fed in the Y-axis direction in the state in which the sewing needle <NUM> is stuck to the sewing object S.

<FIG> is a view illustrating an example of timings that the sewing needle <NUM> and the feed belts <NUM> are synchronized. As shown in <FIG>, it is set that the respective parts are synchronized based on the phase angles of the motors that drive the sewing needle <NUM> and the feed belts <NUM>. Specifically, in both of the belt feed mode and the needle feed mode, the motor <NUM> is controlled, so that the sewing needle <NUM> is stuck to the sewing object S during a period in which the phase is between <NUM>° and <NUM>°. In such case, other operations are controlled in accordance with the motor <NUM>. Accordingly, in both of the belt feed mode and the needle feed mode, the sewing needle <NUM> and the feed belts <NUM> can be easily synchronized.

According to the above, the sewing machine <NUM> according to the embodiment includes: the sewing needle <NUM>, held by the needle rod <NUM> and holding the upper thread to move reciprocally; the shuttle <NUM>, holding the bobbin which is accommodated in the bobbin case and in which the lower thread is wound, and cooperating with the sewing needle to form a seam SE; the pressing member <NUM>, pressing the sewing object S disposed at the sewing position PS immediately below the sewing needle <NUM>; the feed mechanism <NUM>, in which the endless feed belts <NUM> feeding the sewing object S disposed at the sewing position PS from the sewing position PS toward the Y-axis direction are disposed on two sides with respect to the sewing position PS in the X-axis direction orthogonal the Y-axis direction, and in which the belt drive part <NUM> is provided, the belt drive part <NUM> independently driving the feed belts <NUM> on the -X side and the feed belts <NUM> on the +X side in the X-axis direction with respect to the sewing position PS; the needle driving part <NUM>, provided separately from the belt drive part <NUM> and moving the sewing needle <NUM> in the Y-axis direction; and the control part <NUM>, exerting control so that the belt drive part <NUM> and the needle drive part <NUM> operate independently.

According to the configuration, since the belt drive part <NUM> and the needle drive part <NUM> are controlled to operate independently, the specification of feeding the sewing object S can be switched as the control mode. Accordingly, it is easy to switch the specification of delivering the sewing object S without extensively recombining the sewing machine <NUM>.

In the sewing machine <NUM> according to the embodiment, the control part <NUM> performs, as a mode of feeding the sewing object S, the belt feed mode that controls the needle drive part <NUM> and the belt drive part <NUM>, so that the sewing needle <NUM> and the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the sewing needle <NUM> does not move in the Y-axis direction and the feed belts <NUM> move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. According to the configuration, the feed belts <NUM> can feed the sewing object S reliably.

In the sewing machine <NUM> according to the embodiment, the control part <NUM> performs, as a mode of feeding the sewing object S, the needle feed mode that controls the needle drive part <NUM> and the belt drive part <NUM>, so that the sewing needle <NUM> and the feed belts <NUM> move synchronously by the predetermined distance in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the sewing needle <NUM> and the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. According to the configuration, when sewing is performed in the state in which multiple sewing objects S overlap, the sewing objects S can be suppressed from being shifted in the horizontal direction.

In the sewing machine <NUM> according to the embodiment, the control part <NUM> exerts control to be able to switch between the belt feed mode and the needle feed mode. The belt feed mode controls the needle drive part <NUM> and the belt drive part <NUM>, so that the sewing needle <NUM> and the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the sewing needle <NUM> does not move in the Y-axis direction and the feed belts <NUM> move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. The needle feed mode controls the needle drive part <NUM> and the belt drive part <NUM>, so that the sewing needle <NUM> and the feed belts <NUM> move synchronously by the predetermined distance in the Y-axis direction during the period in which the sewing needle <NUM> is stuck to the sewing object S, and the sewing needle <NUM> and the feed belts <NUM> do not move in the Y-axis direction during the period in which the sewing needle <NUM> is withdrawn from the sewing object S. According to the configuration, the belt feed mode and the needle feed mode can be easily switched as a change of the control mode.

Claim 1:
A sewing machine (<NUM>), comprising:
a sewing needle (<NUM>), held by a needle bar (<NUM>) to move reciprocally in a Z-axis direction and holding an upper thread (UT) ;
a pressing member (<NUM>), pressing a sewing object (S) disposed at a sewing position (PS) immediately below the sewing needle (<NUM>);
a feed mechanism (<NUM>), in which endless feed belts (<NUM>) feeding the sewing object (S) disposed at the sewing position (PS) from the sewing position (PS) along a first direction orthogonal to the Z-axis direction are disposed on two sides with respect to the sewing position (PS) in a second direction orthogonal to the first direction and the Z-axis direction, and in which a belt drive part (<NUM>) is provided;
a needle drive part (<NUM>), provided separately from the belt drive part (<NUM>), and moving the sewing needle (<NUM>) in the first direction; and
a control part (<NUM>), exerting control so that the belt drive part (<NUM>) and the needle drive part (<NUM>) are able to operate independently,
the sewing machine (<NUM>) being characterized by further comprising:
a shuttle (<NUM>), holding a bobbin which is accommodated in a bobbin case and in which a lower thread (LT) is wound, and cooperating with the sewing needle (<NUM>) to form a seam (SE); and
in that: the control part (<NUM>) is configured to perform, as a mode of feeding the sewing object (S), a belt feed mode that controls the needle drive part (<NUM>) and the belt drive part (<NUM>), so that the sewing needle (<NUM>) and the feed belts (<NUM>) do not move in the first direction during a period in which the sewing needle (<NUM>) is stuck to the sewing object (S), and the sewing needle (<NUM>) does not move in the first direction and the feed belts (<NUM>) move in the first direction during a period in which the sewing needle (<NUM>) is withdrawn from the sewing object (S).