A sewing machine control method

Abstract

The application provides a sewing machine control method. The sewing machine comprises a needle holder, a feeding needle, a needle lifting assembly and a feeding assembly connected to two ends of the needle holder respectively, a needle lifting driving motor in transmission connection with the needle lifting assembly, a feeding driving motor in transmission connection with the feeding assembly and an electric control module. The sewing machine control method comprises effective feeding time adjustment. When the target effective feeding time is prolonged, the electric control module reduces the swing angular velocity of the needle lifting driving motor and the feeding driving motor when the feeding needle is above a needle plate surface, and increases the swing angular velocity of the needle lifting driving motor and the feeding driving motor when the feeding needle is below the needle plate surface. When the target effective feeding time is shortened, the electric control module increases the swing angular velocity of the needle lifting driving motor and the feeding driving motor when the feeding needle is above the needle plate surface, and reduces the swing angular velocity of the needle lifting driving motor and the feeding driving motor when the feeding needle is below the needle plate surface. The application enables the sewing machine to better adapt to different sewing conditions.

Description

Technical Field

[0001] This invention relates to the field of sewing machine technology, and in particular to a sewing machine control method. Background Technology

[0002] A sewing machine is a machine that uses one or more sewing threads to create one or more stitches on fabric, weaving or sewing together one or more layers of fabric. A sewing machine mainly includes a housing, feed dog mechanism, needle bar mechanism, thread hook mechanism, presser foot mechanism, and thread trimming mechanism. These mechanisms work together to complete the sewing process. To adapt to sewing different fabrics, sewing machines have various functions, such as stitch length adjustment and feed dog height adjustment. However, in existing sewing machines, the proportion of the feed dog's time above the needle plate (i.e., the effective feed time) during operation is not adjustable. That is, the proportion of the feed dog's time above the needle plate is almost the same as the proportion of the feed dog's time below the needle plate. Figure 1 As shown, Figure 1 The t in the figure represents the unit of time, which means that the sewing machine cannot adapt well to different sewing conditions. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a sewing machine control method that can adjust the effective fabric feeding time.

[0004] To achieve the above objectives, the present invention provides a sewing machine control method, comprising the following steps:

[0005] A. A sewing machine is equipped with a feed dog, a feed dog fixed on the feed dog, a feed dog lifting assembly and a feed assembly connected to both ends of the feed dog, a feed dog lifting drive motor connected to the feed dog lifting assembly, a feed feed drive motor connected to the feed feed assembly, and an electronic control module. The feed dog lifting drive motor and the feed feed drive motor are both connected to the electronic control module. The feed dog lifting drive motor and the feed feed drive motor are both independently controlled motors and are independent of the other power sources of the sewing machine.

[0006] B. The sewing machine control method includes adjusting the effective fabric feed time, which includes the following steps:

[0007] B1. Input the target effective fabric feeding time into the electronic control module;

[0008] B2. The electrical control module adjusts the oscillation pattern of the tooth lifting drive motor and the feeding drive motor according to the target effective fabric feeding time:

[0009] When the effective fabric feeding time of the target is extended, the electronic control module reduces the oscillation angular velocity of the tooth lifting drive motor and the feeding drive motor when the feed tooth is above the needle plate surface, and increases the oscillation angular velocity of the tooth lifting drive motor and the feeding drive motor when the feed tooth is below the needle plate surface, but the electronic control module keeps the entire fabric feeding cycle unchanged.

[0010] When the effective fabric feeding time is shortened, the electronic control module increases the oscillation angular velocity of the lifting drive motor and the feeding drive motor when the feed teeth are above the needle plate surface, and decreases the oscillation angular velocity of the lifting drive motor and the feeding drive motor when the feed teeth are below the needle plate surface, but the electronic control module keeps the entire fabric feeding cycle unchanged.

[0011] Furthermore, the sewing machine control method includes adjusting the lifting height of the feed dog, which includes the following steps:

[0012] C1. The electrical control module pre-stores the tooth lifting working range of the tooth lifting drive motor;

[0013] C2. Input the target tooth lifting height into the electronic control module;

[0014] C2. The electronic control module adjusts the swing amplitude of the tooth lifting drive motor within the tooth lifting working range according to the target tooth lifting height, but the electronic control module keeps the swing center line of the tooth lifting drive motor unchanged.

[0015] Furthermore, the sewing machine control method includes adjusting the lifting height of the feed dog, which includes the following steps:

[0016] D1. The electrical control module pre-stores the tooth lifting working range of the tooth lifting drive motor;

[0017] D2. Input the target tooth lifting height into the electronic control module;

[0018] D3. The electronic control module causes the overall swing amplitude of the tooth-lifting drive motor within the tooth-lifting working range to rotate by an angle according to the target tooth-lifting height, but the electronic control module keeps the swing angle of the tooth-lifting drive motor unchanged; at the same time, the electronic control module adjusts the output law of the feeding drive motor according to the target tooth-lifting height to keep the stitch length of the sewing machine unchanged.

[0019] Furthermore, the electronic control module pre-stores a needle pitch coefficient table, which includes several sets of one-to-one corresponding tooth lifting height values ​​and needle pitch coefficients; in step D3, the electronic control module obtains the needle pitch coefficient corresponding to the target tooth lifting height from the needle pitch coefficient table, and then adjusts the output law of the feeding drive motor according to the needle pitch coefficient.

[0020] Furthermore, the tooth-lifting assembly includes a first tooth-lifting crank, a first tooth-lifting connecting rod, a tooth-lifting shaft rotatably supported in the sewing machine base plate, a second tooth-lifting crank and a third tooth-lifting crank respectively fixed at both ends of the tooth-lifting shaft, and a second tooth-lifting connecting rod. The first tooth-lifting crank is connected to a tooth-lifting drive motor and is driven to rotate by the tooth-lifting drive motor. The two ends of the first tooth-lifting connecting rod are respectively hinged to the first tooth-lifting crank and the second tooth-lifting crank. The two ends of the second tooth-lifting connecting rod are respectively hinged to the third tooth-lifting crank and the tooth holder.

[0021] Furthermore, the feeding assembly includes a feeding crank, a feeding connecting rod, and a rotatable gripper seat supported in the sewing machine base plate. The feeding crank is connected to and driven to rotate by the feeding drive motor. A feeding connecting arm extends integrally from the outer circumferential surface of the gripper seat. The two ends of the feeding connecting rod are respectively hinged to the feeding crank and the feeding connecting arm. The gripper seat is connected to the gripper.

[0022] As described above, the sewing machine control method of the present invention has the following beneficial effects:

[0023] In this application, by setting independently controlled tooth lifting drive motor and feed drive motor, the effective fabric feeding time can be adjusted, enabling the sewing machine to better adapt to different sewing conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram showing the distribution of effective fabric feeding time for existing sewing machines.

[0025] Figure 2 This is a schematic diagram of the sewing machine in this application.

[0026] Figure 3 This is a schematic diagram of the tooth lifting drive motor driving the tooth frame and the feeding tooth to reciprocate up and down through the tooth lifting assembly in this application.

[0027] Figure 4 This is a schematic diagram of the feeding drive motor driving the feed frame and feed teeth to reciprocate back and forth through the feeding assembly in this application.

[0028] Figure 5 This is the control logic diagram for adjusting the effective fabric delivery time in this application.

[0029] Figure 6 A schematic diagram illustrating the extension of effective fabric delivery time.

[0030] Figure 7 This is a schematic diagram illustrating the reduction in effective fabric feeding time.

[0031] Figure 8 A schematic diagram showing the changes in the entire fabric feeding cycle when adjusting the effective fabric feeding time.

[0032] Figure 9 This is the control logic diagram for Embodiment 1 of the tooth lifting height adjustment in this application.

[0033] Figure 10 This is a schematic diagram of the swing angle of the second lifting crank in Embodiment 1 for adjusting the lifting height.

[0034] Figure 11 This is a schematic diagram illustrating the change in the movement trajectory of the feeding teeth during tooth lifting height adjustment in Example 1.

[0035] Figure 12 This is the control logic diagram for Embodiment 2 of the tooth lifting height adjustment in this application.

[0036] Figure 13 This is a schematic diagram illustrating the change in the movement trajectory of the feeding tooth during tooth lifting height adjustment in Example 2.

[0037] Component designation explanation

[0038] 10 Dental frame

[0039] 20 feed dog

[0040] 30 Tooth Lifting Components

[0041] 31 First lifting crank

[0042] 32 First lifting linkage

[0043] 33 Tooth lifting shaft

[0044] 34 Second lifting crank

[0045] 35 Third lifting crank

[0046] 36 Second lifting linkage

[0047] 40 Feeding Components

[0048] 41 Feed Crank

[0049] 42 Feeding Link

[0050] 43 Dental bracket

[0051] 50 tooth lifting drive motor

[0052] 60 Feed drive motor

[0053] 70 Needle Bar Mechanism

[0054] 71 Needle bar crank

[0055] 72 Needle bar connecting rod

[0056] 73 Needle bar connecting post

[0057] 74 needle bar

[0058] 75 needles

[0059] 80 spindle

[0060] 90 main motor Detailed Implementation

[0061] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0062] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0063] This application relates to the field of sewing machine technology, and in particular to a sewing machine control method.

[0064] For ease of description, in the following embodiments, the directions are defined as follows: the length direction of the sewing machine is defined as the left-right direction, and the direction towards the head of the sewing machine is the left direction, and the direction towards the tail of the sewing machine is the right direction. The left-right direction is also the axial direction of the main shaft 80 in the sewing machine; the height direction of the sewing machine is defined as the up-down direction, the width direction of the sewing machine is defined as the front-back direction, and the direction of fabric movement when the sewing machine is sewing forward is the front direction.

[0065] This invention provides a sewing machine control method comprising the following steps:

[0066] A. As Figure 2As shown, the sewing machine includes a feed dog 10, a feed dog 20 fixed on the feed dog 10, a feed dog lifting assembly 30 connected to the rear end of the feed dog 10, a feed assembly 40 connected to the front end of the feed dog 10, a feed dog lifting drive motor 50 driven by the feed dog lifting assembly 30, a feed feed drive motor 60 driven by the feed feed assembly 40, and an electronic control module. Both the feed dog lifting drive motor 50 and the feed feed drive motor 60 are communicatively connected to the electronic control module. Both the feed dog lifting drive motor 50 and the feed feed drive motor 60 are independently controlled motors, independent of the other power sources of the sewing machine. Therefore, the feed dog lifting drive motor 50, the feed feed drive motor 60, and the main motor 90 that drives the main shaft 80 in the sewing machine are three independent motors.

[0067] Within a 360° range of rotation of the motor shaft of the tooth-lifting drive motor 50, the operating range of the tooth-lifting drive motor 50 includes the tooth-lifting working area. Within a 360° range of rotation of the motor shaft of the feed drive motor 60, the operating range of the feed drive motor 60 includes the feed working area. During the operation of the sewing machine, the electronic control module controls the rotation of the main motor 90, the oscillation of the tooth-lifting drive motor 50 within the tooth-lifting working area, and the oscillation of the feed drive motor 60 within the feed working area; the main motor 90 drives the main shaft 80 to rotate, and the main shaft 80 drives the needle bar mechanism 70 on its left end to rotate; the tooth-lifting drive motor 50 drives the tooth holder 10 and the feed tooth 20 to reciprocate up and down through the tooth-lifting assembly 30, such as... Figure 3 As shown, the tooth-lifting action is performed; the feeding drive motor 60 drives the tooth frame 10 and the feeding tooth 20 to reciprocate back and forth in the horizontal direction through the feeding assembly 40, as shown. Figure 4 As shown, the feeding action is performed. Therefore, the feed tooth 20 performs a compound motion of up-and-down reciprocating motion and back-and-forth reciprocating motion, which is a two-degree-of-freedom motion; the tooth lifting drive motor 50 drives the feed tooth 20 to swing in the up-and-down direction through the tooth lifting assembly 30. The greater the swing amplitude, the higher the upper limit position of the feed tooth 20, and the higher the tooth lifting height of the feed tooth 20.

[0068] B. Sewing machine control methods include adjusting the effective fabric feed time, such as... Figure 5 As shown, adjusting the effective fabric feeding time includes the following steps:

[0069] B1. Input the target effective fabric feeding time into the electronic control module;

[0070] B2. The electrical control module adjusts the oscillation pattern of the tooth-lifting drive motor 50 and the feeding drive motor 60 according to the target effective fabric feeding time. The oscillation pattern includes the oscillation angular velocity and angular acceleration of the motors.

[0071] When the effective fabric feeding time is extended, the electronic control module reduces the oscillation angular velocity of the lifting drive motor 50 and the feeding drive motor 60 when the feed tooth 20 is above the needle plate surface, and increases the oscillation angular velocity of the lifting drive motor 50 and the feeding drive motor 60 when the feed tooth 20 is below the needle plate surface. However, the electronic control module keeps the entire fabric feeding cycle unchanged. The fabric feeding cycle refers to the time it takes for the main motor 90 to drive the main shaft 80 to rotate one full 360°. After this adjustment, when the feed tooth 20 is above the needle plate surface, the lifting drive motor 50 and the feeding drive motor 60 operate slower than before; when the feed tooth 20 is below the needle plate surface, the lifting drive motor 50 and the feeding drive motor 60 operate faster than before, thus making the time the feed tooth 20 is above the needle plate surface longer than the time it is below the needle plate surface. Figure 6 As shown, the time for the feed dog 20 to move from the needle exit plate to the needle plate has been changed. That is, the number of unit times t occupied by the feed dog 20 above the needle plate surface is greater than the number of unit times t occupied by the feed dog 20 below the needle plate surface. This extends the effective fabric feeding time X before adjustment to the effective fabric feeding time X1 after adjustment. Figure 8 As shown.

[0072] When the effective fabric feeding time is shortened, the electronic control module increases the oscillation angular velocity of the lifting drive motor 50 and the feeding drive motor 60 when the feed tooth 20 is above the needle plate surface, and decreases the oscillation angular velocity of the lifting drive motor 50 and the feeding drive motor 60 when the feed tooth 20 is below the needle plate surface, but keeps the entire fabric feeding cycle constant. After this adjustment, when the feed tooth 20 is above the needle plate surface, the lifting drive motor 50 and the feeding drive motor 60 operate faster than before; when the feed tooth 20 is below the needle plate surface, the lifting drive motor 50 and the feeding drive motor 60 operate slower than before, thus reducing the time the feed tooth 20 is above the needle plate surface to less than the time it is below the needle plate surface. Figure 7 As shown, the time for the feed tooth 20 to move from the needle exit plate to the needle plate has been changed. That is, the number of unit times t occupied by the feed tooth 20 above the needle plate surface is less than the number of unit times t occupied by the feed tooth 20 below the needle plate surface, thus shortening the effective fabric feeding time X before adjustment to the effective fabric feeding time X2 after adjustment. Figure 8 As shown.

[0073] This application modifies the operating speed of the tooth-lifting drive motor 50 and the feed drive motor 60 when extending or shortening the effective fabric feeding time. However, the swing angle range of the tooth-lifting drive motor 50 within its tooth-lifting working range and the swing angle range of the feed drive motor 60 within its feed working range remain unchanged. Therefore, the stitch length and tooth-lifting height of the sewing machine remain constant. Thus, by setting independently controlled tooth-lifting drive motor 50 and feed drive motor 60, this application achieves adjustment of the effective fabric feeding time within a certain range to cope with different sewing conditions, enabling the sewing machine to better adapt to sewing different fabrics and improving the overall machine's multi-scenario adaptability.

[0074] Furthermore, the preferred structure of the feed dog assembly 30 in the sewing machine is as follows: Figure 2 As shown, the tooth-lifting assembly 30 includes a first tooth-lifting crank 31, a first tooth-lifting connecting rod 32, a rotatable tooth-lifting shaft 33 supported in the sewing machine base plate and extending laterally, a second tooth-lifting crank 34 fixed to the right end of the tooth-lifting shaft 33, a third tooth-lifting crank 35 fixed to the left end of the tooth-lifting shaft 33, and a second tooth-lifting connecting rod 36. The first tooth-lifting crank 31 is connected to and driven to rotate by the tooth-lifting drive motor 50. The two ends of the first tooth-lifting connecting rod 32 are respectively hinged to the first tooth-lifting crank 31 and the second tooth-lifting crank 34. The two ends of the second tooth-lifting connecting rod 36 are respectively hinged to the third tooth-lifting crank 35 and the rear end of the tooth holder 10. Preferably, the first tooth-lifting crank 31 is directly fixed to the motor shaft of the tooth-lifting drive motor 50. The tooth-lifting drive motor 50 is a high-performance stepper motor or a high-performance servo motor, and the tooth-lifting drive motor 50 is fixed to the right side of the sewing machine housing.

[0075] Furthermore, the preferred structure of the feeding assembly 40 in the sewing machine is as follows: Figure 2 As shown, the feeding assembly 40 includes a feeding crank 41, a feeding connecting rod 42, and a rotatable feeder seat 43 supported in the sewing machine base plate. The feeding crank 41 is connected to and driven to rotate by the feeding drive motor 60. A feeding connecting arm extends integrally from the outer circumferential surface of the feeder seat 43. The two ends of the feeding connecting rod 42 are respectively hinged to the feeding crank 41 and the feeding connecting arm. The feeder seat 43 is connected to the front end of the feeder 10. Preferably, the feeding crank 41 is directly fixed to the motor shaft of the feeding drive motor 60. The feeding drive motor 60 is a high-performance stepper motor or a high-performance servo motor, and the feeding drive motor 60 is fixed to the bottom surface of the sewing machine base plate.

[0076] Furthermore, the preferred structure of the needle bar mechanism 70 in the sewing machine is as follows: Figure 2As shown, the needle bar mechanism 70 includes a needle bar crank 71 fixed to the left end of the main shaft 80, a needle bar connecting rod 72, a needle bar connecting column 73, a needle bar extending vertically, and a needle 75 installed at the lower end of the needle bar 74. The two ends of the needle bar connecting rod 72 are respectively hinged to the eccentric part on the needle bar crank 71 and the needle bar connecting column 73. The needle bar 74 is supported in the left side of the sewing machine head, which can move up and down reciprocally.

[0077] Furthermore, the sewing machine control method includes adjusting the lifting height of the feed dog 20, which can be done in two ways.

[0078] Example 1 of adjusting the lifting height of the feed tooth 20

[0079] like Figure 9 As shown, the first embodiment of adjusting the lifting height of the feed tooth 20 includes the following steps:

[0080] C1. The tooth lifting working range of the tooth lifting drive motor 50 is pre-stored in the electronic control module;

[0081] C2. Input the target tooth lifting height into the electronic control module;

[0082] C2. The electronic control module adjusts the swing amplitude of the tooth lifting drive motor 50 within the tooth lifting working range according to the target tooth lifting height, but the electronic control module keeps the swing center line of the tooth lifting drive motor 50 unchanged.

[0083] For example, if the swing amplitude of the tooth-lifting drive motor 50 is adjusted to 10°–30°, the angle of the swing center line is 20°, and the swing angle is 20°; and the target tooth-lifting height increases relative to the original tooth-lifting height, then the swing amplitude of the tooth-lifting drive motor 50 is adjusted to 8°–32°, and the swing angle is 24°, but the angle of the swing center line remains 20°. After the swing amplitude of the tooth-lifting drive motor 50 changes, the swing amplitude of the tooth-lifting drive motor 50, driven by the first tooth-lifting crank 31 and the first tooth-lifting connecting rod 32, changes, such as… Figure 10 As shown, the swing amplitudes of the lifting shaft 33 and the third lifting crank 35 change simultaneously, ultimately achieving the purpose of changing the lifting height of the feed tooth 20. Furthermore, in this embodiment, when changing the lifting height of the feed tooth 20, as... Figure 11 As shown, only the vertical movement amplitude of the feed dog 20 is changed, while the front-to-back movement amplitude of the feed dog 20 remains unchanged, that is, the stitch length of the sewing machine remains unchanged, thus improving the sewing effect. Figure 10 The swing angle curve S1 of the second lifting crank 34 corresponds to Figure 11 The motion trajectory Y1 of the feed tooth 20 Figure 10 The swing angle curve S2 of the second lifting crank 34 corresponds to Figure 11 The movement trajectory Y2 of the feed tooth 20.

[0084] Example 2 of adjusting the lifting height of the feed tooth 20

[0085] like Figure 12 As shown, the second embodiment of adjusting the lifting height of the feed tooth 20 includes the following steps:

[0086] D1. The tooth lifting working range of the tooth lifting drive motor 50 is pre-stored in the electronic control module;

[0087] D2. Input the target tooth lifting height into the electronic control module;

[0088] D3. The electronic control module causes the tooth lifting drive motor 50 to rotate its swing amplitude within the tooth lifting working range by an angle according to the target tooth lifting height, but the electronic control module keeps the swing angle of the tooth lifting drive motor 50 unchanged; at the same time, the electronic control module adjusts the output pattern of the feed drive motor 60 according to the target tooth lifting height to keep the stitch length of the sewing machine unchanged.

[0089] For example, if the swing amplitude of the lifting drive motor 50 is adjusted to 10°–30°, the swing angle to 20°, and the angle of the swing center line to 20°, and the target lifting height increases relative to the original lifting height, then the swing amplitude of the lifting drive motor 50 is shifted upwards by 2°. The adjusted swing amplitude of the lifting drive motor 50 is then 12°–32°, and the angle of the swing center line is 22°, but the swing angle remains unchanged at 20°. After the swing amplitude of the lifting drive motor 50 has rotated through this angle, the movement trajectory of the feeding tooth 20 shifts upwards as a whole. Figure 13 As shown; at this time, the electronic control module adjusts the output pattern of the feed drive motor 60 according to the target lifting height, so that the stitch length of the sewing machine remains unchanged. The movement trajectory of the feed dog 20 changes from the original P1 to the adjusted P2. The adjusted lifting height H2 is greater than the original lifting height H1, and the adjusted stitch length L2 is equal to the original stitch length L1. Conversely, when the target lifting height decreases relative to the original lifting height, the swing amplitude of the lifting drive motor 50 is shifted downward as a whole. However, the swing angle is not convenient, causing the movement trajectory of the feed dog 20 to shift downward as a whole. Combined with the adjustment of the output pattern of the feed drive motor 60, the stitch length of the sewing machine remains unchanged.

[0090] Preferably, the electronic control module has a pre-stored needle spacing coefficient table, which includes several sets of one-to-one corresponding tooth lifting height values ​​and needle spacing coefficients, as shown in Table 1 below.

[0091] Table 1 Needle spacing coefficient table

[0092] Tooth elevation height (mm) Needle spacing coefficient 0.6 1.2 0.8 1.1 1.0 1 1.2 1.1 1.4 1.2 … …

[0093] In step D3, the electronic control module obtains the stitch distance coefficient corresponding to the target lifting height from the stitch distance coefficient table, and then adjusts the output pattern of the feed drive motor 60 according to the stitch distance coefficient. For example, taking the lifting height of the feed tooth 20 as 1mm as a reference, the stitch distance coefficient increases when the lifting height increases or decreases, ensuring that the stitch distance remains unchanged before and after the lifting height adjustment.

[0094] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0095] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A sewing machine control method, characterized in that: Includes the following steps: A. A sewing machine is equipped with a toothed frame (10), a feed tooth (20) fixed on the toothed frame (10), a tooth lifting assembly (30) and a feed assembly (40) respectively connected to both ends of the toothed frame (10), a tooth lifting drive motor (50) connected to the tooth lifting assembly (30), a feed drive motor (60) connected to the feed assembly (40), and an electronic control module. The tooth lifting drive motor (50) and the feed drive motor (60) are both connected to the electronic control module. The tooth lifting drive motor (50) and the feed drive motor (60) are both independently controlled motors and are independent of the other power sources of the sewing machine. B. The sewing machine control method includes adjusting the effective fabric feed time, which includes the following steps: B1. Input the target effective fabric feeding time into the electronic control module; B2. The electrical control module adjusts the oscillation pattern of the tooth-lifting drive motor (50) and the feeding drive motor (60) according to the target effective fabric feeding time: When the effective fabric feeding time of the target is extended, the electronic control module reduces the oscillation angular velocity of the tooth lifting drive motor (50) and the feeding drive motor (60) when the feed tooth (20) is above the needle plate surface, and increases the oscillation angular velocity of the tooth lifting drive motor (50) and the feeding drive motor (60) when the feed tooth (20) is below the needle plate surface, but the electronic control module keeps the entire fabric feeding cycle unchanged; When the effective fabric feeding time of the target is shortened, the electronic control module increases the swing angular velocity of the tooth lifting drive motor (50) and the feeding drive motor (60) when the feed tooth (20) is above the needle plate surface, and decreases the swing angular velocity of the tooth lifting drive motor (50) and the feeding drive motor (60) when the feed tooth (20) is below the needle plate surface, but the electronic control module keeps the entire fabric feeding cycle unchanged; When the effective fabric feeding time is extended or shortened, the speed of the lifting tooth drive motor (50) and the speed of the feeding drive motor (60) are changed, but the swing angle range of the lifting tooth drive motor (50) in the lifting tooth working range and the swing angle range of the feeding drive motor (60) in the feeding working range remain unchanged, and the stitch length and lifting tooth height of the sewing machine remain unchanged.

2. The sewing machine control method according to claim 1, characterized in that: The sewing machine control method includes adjusting the lifting height of the feed dog (20), which includes the following steps: C1. The electrical control module pre-stores the tooth lifting working range of the tooth lifting drive motor (50); C2. Input the target tooth lifting height into the electronic control module; C2. The electronic control module adjusts the swing amplitude of the tooth lifting drive motor (50) within the tooth lifting working range according to the target tooth lifting height, but the electronic control module keeps the swing center line of the tooth lifting drive motor (50) unchanged.

3. The sewing machine control method according to claim 1, characterized in that: The sewing machine control method includes adjusting the lifting height of the feed dog (20), which includes the following steps: D1. The electrical control module pre-stores the tooth lifting working range of the tooth lifting drive motor (50); D2. Input the target tooth lifting height into the electronic control module; D3. The electronic control module causes the tooth lifting drive motor (50) to rotate by an angle within the tooth lifting working range according to the target tooth lifting height, but the electronic control module keeps the swing angle of the tooth lifting drive motor (50) unchanged; at the same time, the electronic control module adjusts the output law of the feed drive motor (60) according to the target tooth lifting height, so that the stitch length of the sewing machine remains unchanged.

4. The sewing machine control method according to claim 3, characterized in that: The electronic control module has a pre-stored needle spacing coefficient table, which includes several sets of one-to-one corresponding tooth lifting height values ​​and needle spacing coefficients; in step D3, the electronic control module obtains the needle spacing coefficient corresponding to the target tooth lifting height in the needle spacing coefficient table, and then adjusts the output law of the feeding drive motor (60) according to the needle spacing coefficient.

5. The sewing machine control method according to claim 1, characterized in that: The tooth lifting assembly (30) includes a first tooth lifting crank (31), a first tooth lifting connecting rod (32), a tooth lifting shaft (33) rotatably supported in the sewing machine base plate, a second tooth lifting crank (34) and a third tooth lifting crank (35) respectively fixed at both ends of the tooth lifting shaft (33), and a second tooth lifting connecting rod (36). The first tooth lifting crank (31) is connected to the tooth lifting drive motor (50) and is driven to rotate by the tooth lifting drive motor (50). The two ends of the first tooth lifting connecting rod (32) are respectively hinged to the first tooth lifting crank (31) and the second tooth lifting crank (34). The two ends of the second tooth lifting connecting rod (36) are respectively hinged to the third tooth lifting crank (35) and the tooth holder (10).

6. The sewing machine control method according to claim 1, characterized in that: The feeding assembly (40) includes a feeding crank (41), a feeding connecting rod (42), and a rotatable tooth holder seat (43) supported in the sewing machine base plate. The feeding crank (41) is connected to the feeding drive motor (60) and is driven to rotate by the feeding drive motor (60). A feeding connecting arm extends integrally from the outer circumferential surface of the tooth holder seat (43). The two ends of the feeding connecting rod (42) are respectively hinged to the feeding crank (41) and the feeding connecting arm. The tooth holder seat (43) is connected to the tooth holder (10).

Images