Needle length adjustment method and sewing machine

Abstract

The present invention relates to a stitch length adjustment method and a sewing machine. The stitch length adjustment method is used to adjust the stitch length of the sewing machine. The stitch length adjustment method comprises the following steps: a controller sends a stitch length adjustment signal; a triggering driving source receives the stitch length adjustment signal and drives the adjustment pin to move in the direction of insertion into the front and rear drive components; the main driving source drives the main shaft to keep rotating in the positive direction, and when the first limiting part abuts against the second limiting part, the controller controls the main shaft to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft and the front and rear drive components is an expected value; the stitch length adjustment method provided by the present invention uses the abutment state of the first limiting part and the second limiting part as the stitch length adjustment starting signal, does not need to additionally judge whether the adjustment pin is inserted into the front and rear drive components, and automatically controls the stitch length adjustment process, only requires one adjustment to obtain the expected stitch length, has low labor intensity, and adapts to the development trend of intelligence and automation.

Description

Technical Field

[0001] The present invention relates to the technical field of parameter adjustment of sewing equipment, in particular to a needle distance adjustment method and a sewing machine. Background Art

[0002] In a sewing machine, the main function of the feed mechanism is to continuously lift and pull the fabric on the needle plate through the reciprocating elliptical motion of the feed dog, thereby continuously dragging the fabric to be processed to the machine head, where the needle forms the stitch. Depending on the sewing requirements, the distance between the sewn thread loops varies, which is the stitch length. Since the movement frequency of the machine head remains constant, the stitch length is generally changed by varying the forward and backward movement of the feed dog, thereby adjusting the stitch length to meet different sewing requirements.

[0003] Existing sewing machines are all equipped with a stitch length adjustment mechanism for adjusting the size of the stitch length to meet different sewing requirements. However, the stitch length adjustment mechanism is generally operated manually, and the needle opening shaft is inserted into the limit groove of the front and rear drive components to release the fixed connection between the main shaft and the front and rear drive components, and the relative eccentricity of the front and rear drive components relative to the center of the main shaft is changed by manually rotating the main shaft, thereby changing the forward and backward movement amplitude of the feed tooth frame. However, the above stitch length adjustment method requires manual pressing of the needle opening shaft, and the operation is cumbersome. The size of the stitch length cannot be intuitively reflected to the user. Sometimes the above action needs to be repeated multiple times to adjust to the user's expected stitch length, which is labor-intensive. At the same time, it cannot adapt to the development trend of intelligent and automated sewing machines. Summary of the Invention

[0004] Based on this, it is necessary to provide a stitch length adjustment method and a sewing machine to address the problems that existing sewing machines require manual operation, multiple adjustments are required to obtain the expected stitch length, the labor intensity is high, and they cannot adapt to the development trend of intelligent and automated sewing machines.

[0005] A stitch length adjustment method for adjusting the stitch length of a sewing machine, the sewing machine comprising a main shaft, a front and rear drive assembly, a stitch length adjustment mechanism, a limit mechanism, and a controller, wherein the main shaft is provided with a main drive source, the front and rear drive assembly is connected to the main shaft and can rotate eccentrically with the main shaft; the stitch length adjustment mechanism comprises a trigger drive source and an adjustment pin drivingly connected to the trigger drive source; the limit mechanism comprises a first limit portion and a second limit portion movable relative to the first limit portion; the stitch length adjustment method comprises the following steps:

[0006] The controller sends a needle distance adjustment signal;

[0007] The trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move in a direction of inserting into the front and rear drive assembly;

[0008] The main drive source drives the main shaft to keep rotating in the positive direction. When the first limit part abuts against the second limit part, the controller controls the main shaft to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft and the front and rear drive components is the expected value.

[0009] In the above-mentioned stitch length adjustment method, the user sets the expected stitch length value, and the controller can send a stitch length adjustment signal according to the expected stitch length value set by the user. When the trigger drive source receives the stitch length adjustment signal sent by the controller, the trigger drive source drives the adjustment pin to move in the direction of insertion into the front and rear drive components. At the same time, the main drive source drives the main shaft to keep rotating, and when the main shaft continues to rotate to a certain position and the first limit part abuts against the second limit part, the main shaft cannot continue to rotate in the positive direction, which means that the trigger drive source drives the adjustment pin to be inserted into the front and rear drive components, and the fixed connection between the front and rear drive components and the main shaft is released. The controller obtains the first limit part and the second limit part in the abutment state, and uses this as the stitch length adjustment start signal. The controller controls the main shaft to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft and the front and rear drive components is the expected value, and the stitch length adjustment is completed. This needle distance adjustment method uses the abutment state of the first limit part and the second limit part as the needle distance adjustment starting signal. There is no need to additionally judge whether the adjustment pin is inserted into the front and rear drive components. The needle distance adjustment process is automatically controlled. Only one adjustment is required to obtain the expected needle distance. The labor intensity is low and it adapts to the development trend of intelligence and automation.

[0010] In one embodiment, after the eccentricity between the main shaft and the front and rear drive components reaches a desired value, the needle distance adjustment method further comprises:

[0011] The controller sends a reset signal;

[0012] The trigger driving source receives a reset signal and drives the adjusting pin to move toward a direction of exiting the front-rear driving assembly.

[0013] In one embodiment, when the first limiting portion abuts against the second limiting portion, the controller controls the main shaft to rotate in a direction opposite to the positive direction, specifically including:

[0014] When the first limit portion abuts against the second limit portion, the main shaft cannot maintain rotation in the positive direction. The controller receives a signal that the main shaft rotation is blocked and sends a signal to the main drive source, driving the main shaft to rotate in the direction opposite to the positive direction through the main drive source.

[0015] In one embodiment, the main shaft rotation obstruction signal received by the controller is one of a current change or a voltage change of the main driving source.

[0016] In one embodiment, the front and rear drive assembly includes an eccentric wheel, a needle opening eccentric wheel and a ratchet wheel which are sequentially sleeved on the main shaft, the ratchet wheel is located at the end of the main shaft away from the main drive source, the needle opening eccentric wheel is teeth-connected to the ratchet wheel, the first limiting portion is provided on the needle opening eccentric wheel and protrudes from the end surface of the needle opening eccentric wheel close to the ratchet wheel, the second limiting portion is provided on the ratchet wheel, the trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move in the direction of insertion into the front and rear drive assembly. Specifically:

[0017] The trigger driving source receives a needle distance adjustment signal and drives the adjustment pin to move in a direction of inserting into the needle opening eccentric wheel.

[0018] In one embodiment, the needle opening eccentric wheel is provided with a groove along its end portion, and the opening of the groove faces the ratchet wheel, a pawl plate is movably provided in the groove, and the pawl plate is provided with gear teeth that cooperate with the ratchet wheel, and the trigger drive source drives the adjusting pin to move toward the direction of inserting into the needle opening eccentric wheel, specifically comprising:

[0019] The trigger driving source drives the adjusting pin to move toward the direction of inserting into the needle opening eccentric wheel. When the adjusting pin is inserted into the needle opening eccentric wheel, the adjusting pin abuts against the pawl plate and pushes the pawl plate to move in the groove.

[0020] In one embodiment, an unlocking slot is provided on the needle opening eccentric wheel, and the trigger drive source receives a needle distance adjustment signal and drives the adjustment pin to move in a direction of inserting into the front and rear drive assembly, specifically comprising:

[0021] The trigger driving source receives a needle distance adjustment signal, and the trigger driving source drives the adjustment pin to move toward the direction close to the needle opening eccentric wheel;

[0022] The main driving source drives the main shaft to keep rotating in the positive direction, so that the adjusting pin is inserted into the unlocking groove.

[0023] In one embodiment, the sewing machine further includes a display module, which is in communication with the controller, and the controller sends a stitch length adjustment signal specifically:

[0024] The needle distance parameter is input on the display module, and the display module feeds back the needle distance signal to the controller, which then sends out a needle distance adjustment signal.

[0025] A sewing machine adopts the stitch length adjustment method described in any one of the above technical solutions to adjust the stitch length.

[0026] In the above-mentioned sewing machine, the user sets the expected stitch length value, and the controller can send a stitch length adjustment signal according to the expected stitch length value set by the user. When the trigger drive source receives the stitch length adjustment signal sent by the controller, the trigger drive source drives the adjustment pin to move in the direction of insertion into the front and rear drive components. At the same time, the main drive source drives the main shaft to keep rotating, and when the main shaft continues to rotate to a certain position and the first limit part abuts against the second limit part, the main shaft cannot continue to rotate in the positive direction, which means that the trigger drive source drives the adjustment pin to be inserted into the front and rear drive components, and the fixed connection between the front and rear drive components and the main shaft is released. The controller obtains the first limit part and the second limit part in the abutment state, and uses this as the stitch length adjustment start signal. The controller controls the main shaft to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft and the front and rear drive components is the expected value, and the stitch length adjustment is completed.

[0027] In one embodiment, the sewing machine further includes a display module, which is communicatively connected to the controller and is used for displaying and inputting stitch length parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of a sewing machine provided by the present invention;

[0029] Figure 2 An exploded schematic diagram of the sewing machine provided by the present invention;

[0030] Figure 3 The present invention provides a flow chart of the needle distance adjustment method.

[0031] Reference numerals:

[0032] 100. Sewing machine;

[0033] 110. Main shaft; 111. Main driving source;

[0034] 120, front and rear drive assembly; 121, eccentric wheel; 122, needle opening eccentric wheel; 1221, groove; 1222, unlocking slot; 123, ratchet; 124, pawl plate; 1241, gear teeth;

[0035] 130. Needle distance adjustment mechanism; 131. Trigger drive source; 132. Adjustment pin;

[0036] 140. Limiting mechanism; 141. First limiting portion; 142. Second limiting portion. DETAILED DESCRIPTION

[0037] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0040] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0041] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0042] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0043] The technical solutions provided by the embodiments of the present invention are described below with reference to the accompanying drawings.

[0044] like Figure 1 、 Figure 2 as well as Figure 3 As shown, the present invention provides a stitch length adjustment method, which is used to adjust the stitch length of a sewing machine 100. The sewing machine 100 includes a main shaft 110, a front and rear drive assembly 120, a stitch length adjustment mechanism 130, a limit mechanism 140, and a controller (not shown). The main shaft 110 is provided with a main drive source 111, which is used to drive the main shaft 110 to rotate. In other words, the output shaft of the main drive source 111 is fixedly connected to the main shaft 110. When the main drive source 111 outputs power to the output shaft, the output shaft can drive the main shaft 110 to rotate. The front and rear drive assembly 120 is fixedly connected to the main shaft 110 in a sleeve manner. When the main shaft 110 rotates, the main shaft 110 can drive the front and rear drive assembly 120 to rotate eccentrically. The stitch length adjustment mechanism 130 includes a trigger drive source 131 and an adjustment pin 132, which are transmission-connected to the trigger drive source 131 and the adjustment pin 132. Under the driving action of the trigger driving source 131, the adjusting pin 132 can be inserted into the front and rear driving components 120 to release the fixed connection between the front and rear driving components 120 and the main shaft 110. The limiting mechanism 140 includes a first limiting portion 141 and a second limiting portion 142, and the first limiting portion 141 and the second limiting portion 142 can move relative to each other. When the main shaft 110 rotates to a certain position, the first limiting portion 141 can abut against the second limiting portion 142. At this time, the abutting force between the first limiting portion 141 and the second limiting portion 142 makes it impossible for the main shaft 110 to continue to rotate in the positive direction, which means that the trigger driving source 131 drives the adjusting pin 132 to be inserted into the front and rear driving components 120, releasing the fixed connection between the front and rear driving components 120 and the main shaft 110. Figure 3 As shown, the needle distance adjustment method includes the following steps in sequence:

[0045] Step S301: The controller issues a needle distance adjustment signal. During setup, the user first sets a desired needle distance value. The controller then issues a needle distance adjustment signal based on the user-set desired needle distance value. The controller is in communication with both the main drive source 111 and the trigger drive source 131, enabling them to receive the needle distance adjustment signal from the controller.

[0046] Step S302: The trigger drive source 131 receives the needle distance adjustment signal, and the trigger drive source 131 can drive the adjustment pin 132 to move in the direction of insertion into the front and rear drive assembly 120. It is worth noting that while the trigger drive source 131 drives the adjustment pin 132 to move in the direction of insertion into the front and rear drive assembly 120, the main drive source 111 drives the main shaft 110 to always keep rotating. The adjustment pin 132 can be directly inserted into the front and rear drive assembly 120, or the adjustment pin 132 can first be attached to the circumferential surface of the front and rear drive assembly 120 during the rotation process of the front and rear drive assembly 120, and then inserted into the front and rear drive assembly 120 at the locking position. Regardless of how the adjustment pin 132 is inserted into the front and rear drive assembly 120, when the adjustment pin 132 is inserted into the front and rear drive assembly 120, the adjustment pin 132 can release the fixed connection between the front and rear drive assembly 120 and the main shaft 110.

[0047] Step S303: The main driving source 111 drives the main shaft 110 to keep rotating in the positive direction. When the first limit portion 141 abuts against the second limit portion 142, the controller controls the main shaft 110 to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft 110 and the front and rear driving components 120 is the expected value. Specifically, while the spindle 110 continues to rotate in the positive direction, when the spindle 110 continues to rotate to a certain position and the first limit portion 141 abuts against the second limit portion 142, the spindle 110 can no longer rotate in the positive direction, which means that the trigger drive source 131 drives the adjustment pin 132 to be inserted into the front and rear drive assembly 120, and the fixed connection between the front and rear drive assembly 120 and the spindle 110 is released. The controller obtains the first limit portion 141 and the second limit portion 142 in the abutment state, and uses this as the starting signal for needle length adjustment. The controller controls the spindle 110 to rotate in the direction opposite to the positive direction until the eccentricity between the spindle 110 and the front and rear drive assembly 120 is the expected value, and the needle length adjustment is completed.

[0048] The above-mentioned stitch length adjustment method uses the abutment state of the first limit part 141 and the second limit part 142 as the stitch length adjustment starting signal. There is no need to additionally judge whether the adjustment pin 132 is inserted into the front and rear drive components 120, and the stitch length adjustment process is automatically controlled. Only one adjustment is required to obtain the expected stitch length. The labor intensity is low, and it adapts to the development trend of intelligence and automation of the sewing machine 100.

[0049] Further, in order to enable the sewing machine 100 to perform sewing operations at a desired stitch length, a preferred embodiment is as follows: Figure 1 、 Figure 2 as well as Figure 3 As shown, after the eccentricity between the main shaft 110 and the front and rear drive assembly 120 reaches the expected value, the needle distance adjustment method further includes the following steps:

[0050] Step S304: The controller sends a reset signal. In a specific setting, when the eccentricity between the main shaft 110 and the front and rear drive assembly 120 reaches the expected value, the controller can determine that the needle distance has been adjusted to the expected value and send a reset signal to the main drive source 111 and the trigger drive source 131.

[0051] Step S305: After the trigger driving source 131 receives the reset signal, the trigger driving source 131 drives the adjustment pin 132 to move toward the direction of exiting the front-rear drive assembly 120. When the adjustment pin 132 exits the front-rear drive assembly 120, the fixed connection between the front-rear drive assembly 120 and the main shaft 110 is re-established. The main shaft 110 drives the front-rear drive assembly 120 to rotate eccentrically, thereby controlling the sewing machine 100 to perform sewing operations according to the desired stitch length.

[0052] In order to realize that the controller controls the main shaft 110 to rotate in the direction opposite to the positive direction, as shown in FIG. Figure 1 、 Figure 2 as well as Figure 3 As shown, step S303 is specifically as follows: in the process of the main driving source 111 driving the main shaft 110 to maintain rotation in the positive direction, when the first limit portion 141 abuts against the second limit portion 142, the main shaft 110 cannot maintain rotation in the positive direction, and the controller receives a signal that the rotation of the main shaft 110 is blocked, and sends a signal to the main driving source 111, driving the main shaft 110 to rotate in the direction opposite to the positive direction through the main driving source 111.

[0053] In the above-mentioned needle length adjustment method, when the main shaft 110 rotates to a certain position and the first limit part 141 abuts against the second limit part 142, since the main shaft 110 cannot continue to rotate in the positive direction, the controller receives a signal that the rotation of the main shaft 110 is blocked, which means that the trigger drive source 131 drives the adjustment pin 132 to be inserted into the front and rear drive components 120, and the fixed connection between the front and rear drive components 120 and the main shaft 110 is released. The controller sends a signal to the main drive source 111 and drives the main shaft 110 to rotate in the direction opposite to the positive direction through the main drive source 111. Compared with the traditional method that requires manual judgment or detection device to detect whether the adjustment pin 132 is inserted into the front and rear drive components 120, in this embodiment, the controller only needs to receive a signal that the rotation of the main shaft 110 is blocked to determine that the adjustment pin 132 has been inserted into the front and rear drive components 120, and the fixed connection between the front and rear drive components 120 and the main shaft 110 is released to serve as the starting signal for stitch length adjustment. The judgment method is simple and reliable, and the labor intensity is greatly reduced, which can improve the efficiency of stitch length adjustment or reduce sewing costs.

[0054] Specifically, the controller receives a signal indicating that the rotation of the main shaft 110 is blocked, which is a current change or a voltage change of the main drive source 111. Since the current or voltage of the main drive source 111 used to drive the main shaft 110 to rotate will change significantly when the main shaft 110 is unable to continue to rotate in the positive direction, the controller determines the current change or voltage change signal and uses it as a signal that the adjustment pin 132 has been inserted into the front and rear drive assembly 120, thereby releasing the fixed connection between the front and rear drive assembly 120 and the main shaft 110, that is, as a stitch length adjustment start signal. The determination signal is simple and reliable, and can replace traditional manual determination methods or detection methods of detection devices, greatly reducing labor intensity, improving stitch length adjustment efficiency, or reducing sewing costs.

[0055] In order to adjust the relative eccentricity between the axis of the main shaft 110 and the front and rear drive components 120, a preferred embodiment is as follows: Figure 1 、 Figure 2 as well as Figure 3As shown, the front-to-back drive assembly 120 includes an eccentric wheel 121, a needle opening eccentric wheel 122, and a ratchet wheel 123. The eccentric wheel 121, the needle opening eccentric wheel 122, and the ratchet wheel 123 are sequentially sleeved on the main shaft 110 to securely connect the front-to-back drive assembly 120 to the main shaft 110. The ratchet wheel 123 is located at the end of the main shaft 110 away from the main drive source 111. In other words, the eccentric wheel 121 is located at the end of the main shaft 110 close to the main drive source 111. The needle opening eccentric wheel 122 is toothed on the ratchet wheel 123. A first limiting portion 141 is provided on the needle opening eccentric wheel 122, and the first limiting portion 141 protrudes from the end surface of the needle opening eccentric wheel 122 close to the ratchet wheel 123. The second limiting portion 142 is provided on the ratchet wheel 123. Step S302 is specifically as follows: triggering the driving source 131 to receive the needle distance adjustment signal, triggering the driving source 131 to drive the adjustment pin 132 to move in the direction of inserting into the needle opening eccentric wheel 122 .

[0056] The above-mentioned stitch length adjustment device, since the first limiting part 141 and the second limiting part 142 can move relative to each other, when the first limiting part 141 and the second limiting part 142 abut against each other, the ratchet 123 cannot continue to rotate. Since the ratchet 123 and the main shaft 110 are still fixedly connected, the main shaft 110 cannot continue to rotate in the positive direction, which means that the adjustment pin 132 has been inserted into the needle opening eccentric wheel 122, and the fixed connection between the needle opening eccentric wheel 122 and the main shaft 110 is released, thereby indirectly releasing the fixed connection between the front and rear drive components 120 and the main shaft 110. The controller obtains that the first limit part 141 and the second limit part 142 are in abutment state, and uses this as the starting signal for stitch length adjustment, and controls the main drive source 111 to rotate the main shaft 110 in the direction opposite to the positive direction until the relative eccentricity between the axis of the main shaft 110 and the front and rear drive components 120 is the expected value. After obtaining the expected stitch length, the drive source 131 is triggered to drive the adjustment pin 132 to exit the needle opening eccentric wheel 122, and the needle opening eccentric wheel 122 is re-connected to the main shaft 110, indirectly making the front and rear drive components 120 re-connected to the main shaft 110, and the main shaft 110 drives the front and rear drive components 120 to rotate eccentrically, controlling the cloth feeding component to perform sewing operations with the expected stitch length.

[0057] Specifically, if Figure 1 、 Figure 2 as well as Figure 3As shown, a groove 1221 is formed at the end of the needle opening eccentric wheel 122. The groove 1221 is located at the end of the needle opening eccentric wheel 122 near the ratchet wheel 123 and extends a certain thickness toward the interior of the needle opening eccentric wheel 122. The opening of the groove 1221 faces the ratchet wheel 123. A ratchet plate 124 is provided in the groove 1221. The ratchet plate 124 is movable in the groove 1221. The ratchet plate 124 is provided with gear teeth 1241. The gear teeth 1241 can cooperate with the ratchet wheel 123 to fix the needle opening eccentric wheel 122 to the ratchet wheel 123, thereby indirectly fixing the front and rear drive assembly 120 to the main shaft 110, and the front and rear drive assembly 120 can rotate eccentrically with the main shaft 110. The triggering driving source 131 drives the adjusting pin 132 to move toward the direction of inserting the needle opening eccentric wheel 122, specifically including: the triggering driving source 131 drives the adjusting pin 132 to move toward the direction of inserting the needle opening eccentric wheel 122, and when the adjusting pin 132 is inserted into the needle opening eccentric wheel 122, the adjusting pin 132 abuts against the ratchet plate 124 and pushes the ratchet plate 124 to move in the groove 1221.

[0058] When the first limit portion 141 abuts against the second limit portion 142, it indicates that the adjusting pin 132 has been inserted into the needle opening eccentric 122, and the fixed connection between the front and rear drive components 120 and the main shaft 110 is released to adjust the needle length. When the expected stitch length is adjusted, the adjusting pin 132 withdraws from the needle opening eccentric wheel 122, the ratchet plate 124 is reset, and the gear teeth 1241 contact the ratchet 123, thereby re-establishing the fixed connection between the needle opening eccentric wheel 122 and the ratchet 123, that is, re-establishing the fixed connection between the front and rear drive assemblies 120 and the main shaft 110. The front and rear drive assemblies 120 can rotate eccentrically with the main shaft 110, thereby controlling the sewing machine 100 to perform sewing operations at the expected stitch length.

[0059] It should be noted that a reset member (not shown) is connected to the pawl plate 124 so that when the adjustment pin 132 abuts against the pawl plate 124, the pawl plate 124 can move within the groove 1221, releasing the fixed connection between the needle opening eccentric wheel 122 and the ratchet wheel 123; and when the adjustment pin 132 withdraws from the pawl plate 124, the pawl plate 124 can reset and re-establish the fixed connection between the needle opening eccentric wheel 122 and the ratchet wheel 123. The reset member can be a spring, an elastic sheet, or other elastic element, and the present invention does not limit the specific type of the reset member.

[0060] In order to release the fixed connection between the front and rear drive components 120 and the main shaft 110, a preferred embodiment is as follows Figure 1 、 Figure 2 as well as Figure 3 As shown, the needle opening eccentric wheel 122 is provided with an unlocking slot 1222, and the adjusting pin 132 can be inserted into or withdrawn from the unlocking slot 1222, that is, the adjusting pin 132 can be inserted into or withdrawn from the front and rear drive assembly 120, thereby releasing or re-establishing the fixed connection between the front and rear drive assembly 120 and the main shaft 110. Step S302 specifically includes:

[0061] After the trigger driving source 131 receives the stitch length adjustment signal, the trigger driving source 131 drives the adjustment pin 132 to move toward the direction close to the needle opening eccentric wheel 122. In specific operation, after the trigger driving source 131 receives the stitch length adjustment signal, the trigger driving source 131 drives the adjustment pin 132 to move toward the direction close to the needle opening eccentric wheel 122, so as to prepare for the adjustment pin 132 to be inserted into the unlocking slot 1222.

[0062] The main drive source 111 drives the main shaft 110 to keep rotating in the positive direction, so that the adjustment pin 132 is inserted into the unlocking slot 1222. When the trigger drive source 131 drives the adjustment pin 132 to move toward the needle opening eccentric wheel 122, the main drive source 111 drives the main shaft 110 to keep rotating in the positive direction, so that the adjustment pin 132 can be inserted into the unlocking slot 1222, thereby releasing the fixed connection between the needle opening eccentric wheel 122 and the main shaft 110, and indirectly releasing the fixed connection between the front and rear drive assembly 120 and the main shaft 110.

[0063] In order to intuitively reflect the needle length to the user, a preferred embodiment is as follows: Figure 1 、 Figure 2 as well as Figure 3As shown, sewing machine 100 also includes a display module (not shown), for displaying and inputting stitch length parameters, and the display module is connected to the controller by means of Bluetooth, wireless or other communication. The specific operation of step S301 is that the user inputs the stitch length parameter on the display module, and the display module feeds back the stitch length parameter signal to the controller, and the controller sends a stitch length adjustment signal, and performs corresponding actions by the main drive source 111 and the trigger drive source 131, to adjust the stitch length. The stitch length can be intuitively reflected by the display module, and the signal is fed back to the controller, and the controller is intelligentized and automatically adjusted to adjust the stitch length, prevent manual operation from causing stitch length adjustment error, or need to repeatedly adjust the stitch length to obtain the expected stitch length value, reduce the stitch length adjustment labor intensity.

[0064] In addition, the present invention further provides a sewing machine 100, which uses the stitch length adjustment method of any one of the above technical solutions to adjust the stitch length.

[0065] In the above-mentioned sewing machine 100, the user sets the expected stitch length value, and the controller can send a stitch length adjustment signal according to the expected stitch length value set by the user. When the trigger driving source 131 receives the stitch length adjustment signal sent by the controller, the trigger driving source 131 drives the adjustment pin 132 to move in the direction of inserting the front and rear drive components 120. At the same time, the main driving source 111 drives the main shaft 110 to keep rotating, and when the main shaft 110 continues to rotate to a certain position, the first limit portion 141 abuts against the second limit portion 142, the main shaft 110 0 cannot continue to rotate in the positive direction, which means that the trigger drive source 131 drives the adjustment pin 132 to be inserted into the front and rear drive assembly 120, and the fixed connection between the front and rear drive assembly 120 and the main shaft 110 is released. The controller obtains that the first limit part 141 and the second limit part 142 are in abutment state, and uses this as the starting signal for needle length adjustment. The controller controls the main shaft 110 to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft 110 and the front and rear drive assembly 120 is the expected value, and the needle length adjustment is completed.

[0066] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A stitch length adjustment method for adjusting the stitch length of a sewing machine, wherein the sewing machine comprises a main shaft, a front and rear drive assembly, a stitch length adjustment mechanism, a limit mechanism, and a controller, wherein the main shaft is provided with a main drive source, the front and rear drive assembly is connected to the main shaft and can rotate eccentrically with the main shaft; the stitch length adjustment mechanism comprises a trigger drive source and an adjustment pin drivingly connected to the trigger drive source; the limit mechanism comprises a first limit portion and a second limit portion that can move relative to the first limit portion; and is characterized in that: The front and rear drive assembly includes an eccentric wheel, a needle opening eccentric wheel and a ratchet wheel which are sequentially sleeved on the main shaft. The stitch length adjustment method includes the following steps: The controller sends a needle distance adjustment signal; The trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move in a direction of inserting into the front and rear drive assembly; The main drive source drives the main shaft to rotate in the positive direction. When the first limit portion abuts against the second limit portion, the controller controls the main shaft to rotate in the direction opposite to the positive direction until the eccentricity between the main shaft and the front and rear drive assemblies reaches a desired value. Specifically, the trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move toward the direction of inserting into the front and rear drive components. Specifically, the trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move toward the direction of inserting into the needle opening eccentric wheel.

2. The needle distance adjustment method according to claim 1, characterized in that: After the eccentricity between the main shaft and the front and rear drive components reaches a desired value, the needle distance adjustment method further includes: The controller sends a reset signal; The trigger driving source receives a reset signal and drives the adjusting pin to move toward a direction of exiting the front-rear driving assembly.

3. The needle distance adjustment method according to claim 1, characterized in that: When the first limiting portion abuts against the second limiting portion, the controller controls the main shaft to rotate in a direction opposite to the positive direction, specifically including: When the first limit portion abuts against the second limit portion, the main shaft cannot maintain rotation in the positive direction. The controller receives a signal that the main shaft rotation is blocked and sends a signal to the main drive source, driving the main shaft to rotate in the direction opposite to the positive direction through the main drive source.

4. The needle distance adjustment method according to claim 3, characterized in that: The controller receives the main shaft rotation obstruction signal as one of a current change and a voltage change of the main driving source.

5. The needle distance adjustment method according to claim 1, characterized in that: The ratchet is located at the end of the main shaft away from the main driving source, the needle opening eccentric wheel is teeth-connected to the ratchet, the first limiting portion is arranged on the needle opening eccentric wheel and protrudes from the end face of the needle opening eccentric wheel close to the ratchet, and the second limiting portion is arranged on the ratchet.

6. The needle distance adjustment method according to claim 5, characterized in that: The needle opening eccentric wheel is provided with a groove along its end portion, and the opening of the groove faces the ratchet wheel. A pawl plate is movably provided in the groove, and the pawl plate is provided with gear teeth that cooperate with the ratchet wheel. The trigger drive source drives the adjusting pin to move in the direction of inserting into the needle opening eccentric wheel, specifically including: The trigger driving source drives the adjusting pin to move toward the direction of inserting into the needle opening eccentric wheel. When the adjusting pin is inserted into the needle opening eccentric wheel, the adjusting pin abuts against the pawl plate and pushes the pawl plate to move in the groove.

7. The needle distance adjustment method according to claim 6, characterized in that: The needle opening eccentric wheel is provided with an unlocking slot, and the trigger drive source receives the needle distance adjustment signal and drives the adjustment pin to move in the direction of inserting into the front and rear drive components, specifically including: The trigger driving source receives a needle distance adjustment signal, and the trigger driving source drives the adjustment pin to move toward the direction close to the needle opening eccentric wheel; The main driving source drives the main shaft to keep rotating in the positive direction, so that the adjusting pin is inserted into the unlocking groove.

8. The needle distance adjustment method according to claim 1, characterized in that: The sewing machine further includes a display module, which is in communication with the controller. The controller sends a stitch length adjustment signal specifically: The needle distance parameter is input on the display module, and the display module feeds back the needle distance signal to the controller, which then sends out a needle distance adjustment signal.

9. A sewing machine, characterized in that: The sewing machine adjusts the stitch length using the stitch length adjustment method according to any one of claims 1 to 8.

10. The sewing machine according to claim 9, characterized in that The sewing machine further comprises a display module, which is communicatively connected with the controller and is used for displaying and inputting stitch length parameters.

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