Column sewing machine and control method thereof

Abstract

The invention discloses a stand column sewing machine and a control method thereof. The stand column sewing machine comprises a machine shell, a needle rod, a machine needle, an upper feeding wheel assembly, an upper feeding wheel motor, a lower feeding wheel assembly, a lower feeding wheel motor and a control unit. The needle is fixed at one end of the needle rod; the control unit is electrically connected with the upper feeding wheel motor and the lower feeding wheel motor. The upper feeding wheel motor is fixedly connected with the upper feeding wheel assembly, and the lower feeding wheel motor is fixedly connected with the lower feeding wheel assembly. In the operation process, the upper feeding wheel assembly and the lower feeding wheel assembly are used for clamping and moving sewing materials. The needle rod is used for moving only in the first direction so as to sew the sewing material. According to the technical scheme, a needle swing feeding mechanism is omitted, the problem that sewing stability is poor due to abrasion caused by long-term operation of the needle swing feeding mechanism is solved, and the problem that noise is generated due to frequent starting and stopping of feeding of the needle swing feeding mechanism is solved.

Description

Technical Field

[0001] This invention relates to the field of sewing machine technology, and more particularly to a column sewing machine and its control method. Background Technology

[0002] Traditional column-mounted single-needle sewing machines typically use three independent stepper motors to drive the upper feed, lower feed, and needle swing feed mechanisms respectively. The needle swing mechanism uses a complex linkage system to cause the needle to swing longitudinally after it pierces the fabric, moving the needle and fabric together to compensate for differences in feed between the upper and lower layers. This mechanical solution has the following drawbacks:

[0003] Complex structure and high cost: It requires a large number of parts such as a needle pendulum motor, a pendulum needle motor mounting base, a connecting rod, and a swaying needle bar seat. The slide groove that cooperates with the swaying needle bar seat must also be designed to follow the swaying installation method, resulting in high overall cost and assembly complexity.

[0004] Poor reliability: The needle pendulum mechanism itself is a complex motion source. The connecting rods and hinges of the needle pendulum mechanism have inherent fit clearances. Long-term high-speed operation is prone to wear, which leads to a decrease in motion accuracy and directly affects the uniformity and stability of the sewing stitch.

[0005] Performance limitations: Frequent starting, stopping, and reversing of the needle swing mechanism produce a noticeable jerking sensation, increasing vibration and noise during the sewing process;

[0006] Insufficient rigidity: Traditional column-type sewing machines use needle feeding, and the needle bar holder is prone to vibration and noise when it swings. Summary of the Invention

[0007] This invention provides a column sewing machine and its control method to solve the problems of existing sewing machines, such as complex structure, high cost, poor reliability, limited performance, and insufficient rigidity.

[0008] According to one aspect of the present invention, a post sewing machine is provided, comprising:

[0009] Machine housing, needle bar, needle, upper guide sleeve of needle bar, upper feed wheel motor, lower feed wheel assembly, lower feed wheel motor and control unit;

[0010] The needle is fixed to one end of the needle bar;

[0011] The control unit is electrically connected to the upper feed wheel motor and the lower feed wheel motor respectively; the upper feed wheel motor is fixedly connected to the upper feed wheel assembly, and the lower feed wheel motor is fixedly connected to the lower feed wheel assembly; the control unit is used to control the upper feed wheel motor to run at a first speed and control the lower feed wheel motor to run at a second speed according to the needle bar movement position;

[0012] During operation, the upper feed wheel assembly and the lower feed wheel assembly are used to clamp and move the sewing material; the needle bar is used to move only along a first direction to sew the sewing material; wherein, the first direction is the extension direction of the needle bar.

[0013] Optionally, it also includes: an upper guide sleeve for the needle bar and a lower guide sleeve for the needle bar;

[0014] Both the upper guide sleeve and the lower guide sleeve of the needle bar are fixedly mounted on the machine housing and are sleeved on the needle bar; the first direction includes the direction from the upper guide sleeve of the needle bar to the lower guide sleeve of the needle bar and the direction from the lower guide sleeve of the needle bar to the upper guide sleeve of the needle bar.

[0015] Optional components also include a spindle motor, a spindle cam assembly, a slide, and a slider;

[0016] The needle bar and the main spindle cam assembly are fixedly connected to the slider; the slide groove is fixed to the machine housing and slidably connected to the slider; the main spindle cam assembly is fixedly connected to the main spindle motor.

[0017] The control unit is electrically connected to the spindle motor and is used to control the rotation of the spindle motor so as to drive the needle bar to move in the first direction.

[0018] Optionally, a current detection unit may also be included; the current detection unit is used to detect the load current of the spindle motor.

[0019] The control unit is electrically connected to the current detection unit and is used to acquire the load current and control the running speed of the upper feed wheel motor and the running speed of the lower feed wheel motor according to the load current.

[0020] Optional components also include a presser foot lifting motor, a presser foot lifting cam, a presser foot pressure cam, a presser foot lifting crank mechanism, a presser foot pressure mechanism, a presser foot bar mechanism, and a thickness detection assembly;

[0021] The presser foot lifting motor is fixedly connected to the presser foot lifting cam and the presser foot pressure cam respectively; the presser foot lifting cam is fixedly connected to the presser foot bar mechanism through the presser foot lifting crank mechanism; the presser foot pressure cam is connected to the presser foot bar mechanism through the presser foot pressure mechanism; the presser foot bar mechanism is fixedly connected to the upper feed wheel assembly and the thickness detection assembly respectively.

[0022] The control unit is electrically connected to the lifting foot motor and is used to acquire the thickness signal from the thickness detection component and control the forward or reverse rotation angle of the lifting foot motor according to the thickness signal.

[0023] According to another aspect of the present invention, a control method for a column sewing machine is provided, which is applied in a column sewing machine;

[0024] Control methods include:

[0025] Obtain the position of the needle bar movement;

[0026] The upper feed wheel motor is controlled to run at a first speed and the lower feed wheel motor is controlled to run at a second speed based on the position of the needle bar.

[0027] Optionally, the column sewing machine also includes a spindle motor, a spindle cam assembly, a slide, and a slider; the first speed includes a first-stage speed, a second-stage speed, a third-stage speed, and a fourth-stage speed; the second speed includes a fifth-stage speed, a sixth-stage speed, a seventh-stage speed, and an eighth-stage speed; the encoder angle of the spindle motor determines the needle bar movement position;

[0028] Controlling the upper feed wheel motor to run at a first speed and the lower feed wheel motor to run at a second speed based on the needle bar's movement position includes:

[0029] Obtain the encoder angle;

[0030] When the encoder angle is equal to the first preset angle, the upper feed wheel motor is controlled to run at the first stage speed, and the lower feed wheel motor is controlled to run at the fifth stage speed.

[0031] When the encoder angle is equal to the second preset angle, the upper feed wheel motor is controlled to run at the second stage speed, and the lower feed wheel motor is controlled to run at the sixth stage speed.

[0032] When the encoder angle is equal to the third preset angle, the upper feed wheel motor is controlled to run at the third stage speed, and the lower feed wheel motor is controlled to run at the seventh stage speed.

[0033] When the encoder angle is equal to the fourth preset angle, the upper feed wheel motor is controlled to run at the fourth stage speed, and the lower feed wheel motor is controlled to run at the eighth stage speed.

[0034] Optionally, the first preset angle is the encoder angle corresponding to the first height from when the needle leaves the sewing material; in the first stage speed, the acceleration of the upper feed wheel increases from 0 to a; in the fifth stage speed, the acceleration of the lower feed wheel increases from 0 to b; where a > 0 and is a constant; b > 0 and is a constant.

[0035] The second preset angle is the encoder angle corresponding to the second height from when the needle leaves the sewing material; the acceleration of the upper feed wheel is 0 in the second stage speed; the acceleration of the lower feed wheel is 0 in the sixth stage speed;

[0036] The third preset angle is the encoder angle corresponding to the third height when the needle approaches the sewing material; in the third stage speed, the acceleration of the upper feed wheel decreases from 0 to c; in the seventh stage speed, the acceleration of the lower feed wheel decreases from 0 to d; where c < 0 and is a constant; d < 0 and is a constant;

[0037] The fourth preset angle is the encoder angle corresponding to the fourth height when the needle approaches the sewing material; the acceleration of the upper feed wheel in the fourth stage speed is e; the acceleration of the lower feed wheel in the eighth stage speed is f; where e is a constant; f is a constant.

[0038] The second altitude is greater than the first altitude; the third altitude is greater than the fourth altitude.

[0039] Optionally, the column sewing machine may also include a presser foot lifting motor, a presser foot lifting cam, a presser foot pressure cam, a presser foot lifting crank mechanism, a presser foot pressure mechanism, a presser foot bar mechanism, and a thickness detection component;

[0040] After controlling the upper feed wheel motor to run at a first speed and the lower feed wheel motor to run at a second speed based on the needle bar's movement position, the following is also included:

[0041] Acquire the thickness signal from the thickness detection component;

[0042] The forward or reverse rotation angle of the presser foot motor is controlled based on the thickness signal.

[0043] The technical solution of this invention, by setting an upper guide sleeve and a lower guide sleeve for the needle bar in a column sewing machine, with both the upper and lower guide sleeves fixedly mounted on the machine housing and fitted onto the needle bar, allows the needle bar to reciprocate only in a first direction. The upper and lower feed wheel assemblies cooperate to feed the needle, eliminating the need for a needle pendulum feeding mechanism, simplifying the structure of the column sewing machine, saving costs, avoiding the problem of poor sewing stability caused by long-term wear of the needle pendulum feeding mechanism, and avoiding the noise problem caused by frequent start-stop feeding of the needle pendulum feeding mechanism.

[0044] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the overall structure of a column sewing machine according to an embodiment of the present invention;

[0047] Figure 2 This is an exploded structural diagram of a column sewing machine according to an embodiment of the present invention;

[0048] Figure 3 This is a connection diagram of a column sewing machine according to an embodiment of the present invention;

[0049] Figure 4 This is a flowchart of a control method for a first type of column sewing machine according to an embodiment of the present invention;

[0050] Figure 5 This is a flowchart of a control method for a second type of column sewing machine provided according to an embodiment of the present invention;

[0051] Figure 6 This is a flowchart of a third type of control method for a column sewing machine provided according to an embodiment of the present invention;

[0052] Figure 7 This is a flowchart of a control method for a fourth type of column sewing machine provided according to an embodiment of the present invention;

[0053] Figure 8 This is a flowchart of a fifth type of control method for a column sewing machine provided according to an embodiment of the present invention. Detailed Implementation

[0054] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0055] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0056] Figure 1 This is a schematic diagram of the overall structure of a column sewing machine according to an embodiment of the present invention. Figure 2 This is an exploded structural diagram of a column sewing machine according to an embodiment of the present invention. Figure 3This is a connection diagram of a column sewing machine according to an embodiment of the present invention. Figure 1 , Figure 2 and Figure 3 As shown, the column sewing machine includes:

[0057] Machine housing 1, needle bar 10, needle 13, upper feed wheel assembly 15, upper feed wheel motor 14, lower feed wheel assembly 16, lower feed wheel motor 17, and control unit 2;

[0058] The needle 13 is fixed to one end of the needle bar 10;

[0059] The control unit 2 is electrically connected to the upper feed wheel motor 14 and the lower feed wheel motor 17 respectively; the upper feed wheel motor 14 is fixedly connected to the upper feed wheel assembly 15, and the lower feed wheel motor 17 is fixedly connected to the lower feed wheel assembly 16; the control unit 2 is used to control the upper feed wheel motor 14 to run at a first speed and control the lower feed wheel motor 17 to run at a second speed according to the needle bar movement position.

[0060] During operation, the upper feed wheel assembly 15 and the lower feed wheel assembly 16 are used to clamp and move the sewing material; the needle bar 10 is used to move only along a first direction to sew the sewing material; wherein, the first direction is the extension direction of the needle bar 10.

[0061] The housing 1 serves to support and protect the various components of the column sewing machine. In some embodiments, it also includes an upper needle bar guide sleeve 11 and a lower needle bar guide sleeve 12. The upper needle bar guide sleeve 11 and the lower needle bar guide sleeve 12 are fixed to the housing 1 and limit the movement path of the needle bar 10. The needle 13 is fixed to one end of the needle bar 10. The upper needle bar guide sleeve 11 and the lower needle bar guide sleeve 12 are both sleeved on the needle bar 10. The first direction includes the direction from the upper needle bar guide sleeve 11 to the lower needle bar guide sleeve 12 and the direction from the lower needle bar guide sleeve 12 to the upper needle bar guide sleeve 11. The needle bar 10 can reciprocate up and down along the directions of the upper needle bar guide sleeve 11 and the lower needle bar guide sleeve 12, thereby driving the needle 13 to reciprocate for sewing.

[0062] It is understood that, in this embodiment of the invention, due to the limiting effect of the upper guide sleeve 11 and the lower guide sleeve 12 of the needle bar, the needle bar 10 can only reciprocate along the first direction and cannot swing or move longitudinally. The movement of the needle bar 10 can be driven by a mechanical structure, and this embodiment of the invention does not specifically limit the mechanical structure.

[0063] In this embodiment of the invention, the needle bar 10 moves only along the first direction. Any structural design that can achieve the same positioning function is acceptable. For example, an upper guide sleeve 11 and a lower guide sleeve 12 can be provided on the needle bar. Alternatively, the needle bar seat can be fixed to the machine housing 1, and a sliding groove can be provided inside it so that the needle bar 10 passes through the upper and lower guide holes on the needle bar seat. Or the needle bar seat and the sliding groove can be fixed independently to the machine housing 1, and the needle bar 10 can move through the upper and lower guide holes of the needle bar seat. Other mechanical connection forms that can realize that the needle only performs up and down reciprocating motion and the motion trajectory is fixed can also be used.

[0064] The upper feed roller motor 14 is fixedly connected to the upper feed roller assembly 15, and the upper feed roller motor 14 drives the upper feed roller assembly 15 to move. The lower feed roller motor 17 is fixedly connected to the lower feed roller assembly 16, and the lower feed roller motor 17 drives the lower feed roller assembly 16 to move. The sewing material is held between the upper feed roller assembly 15 and the lower feed roller assembly 16, and the movement of the upper feed roller assembly 15 and the lower feed roller assembly 16 serves to transport the sewing material. Since the lower feed roller assembly 16 and the lower feed roller motor 17 are located below the sewing material, this type of sewing machine is a column sewing machine. The control unit 2 is electrically connected to the upper feed roller motor 14 and the lower feed roller motor 17 respectively, and can control the speed of the upper feed roller motor 14 and the speed of the lower feed roller motor 17, thereby controlling the conveying speed of the sewing material.

[0065] The needle bar's position represents the distance between the needle 13 and the fabric. This distance is used to determine the feeding speed, which in turn controls the speeds of the upper feed wheel motor 14 and the lower feed wheel motor 17. The first speed and the second speed represent the speeds during operation; these are not constant values ​​and can vary depending on the needle bar's position. In this embodiment, the first and second speeds can be the same or different, and can be set according to requirements.

[0066] It is understood that the technical solution of this invention eliminates the needle pendulum feeding mechanism, that is, it eliminates the needle pendulum feeding motor, needle bar seat, needle pendulum connecting rod, needle pendulum motor fixing seat and all mechanical mechanisms that cause the needle 13 to generate longitudinal feeding motion in the prior art. Instead, it adopts a guiding scheme in which the upper guide sleeve 11 and the lower guide sleeve 12 of the needle bar are directly fixed to the machine housing 1. During the sewing process, the needle 13 does not participate in the feeding behavior. Only the upper feeding wheel assembly 15 and the lower feeding wheel assembly 16 cooperate to feed the material, ensuring that the needle 13 does not have longitudinal relative motion with the sewing material to provide feeding power after it pierces the sewing material until it withdraws.

[0067] The technical solution of this invention, by setting an upper guide sleeve and a lower guide sleeve for the needle bar in a column sewing machine, with both the upper and lower guide sleeves fixedly mounted on the machine housing and fitted onto the needle bar, allows the needle bar to reciprocate only in a first direction. The upper and lower feed wheel assemblies cooperate to feed the needle, eliminating the need for a needle pendulum feeding mechanism, simplifying the structure of the column sewing machine, saving costs, avoiding the problem of poor sewing stability and reliability caused by long-term wear of the needle pendulum feeding mechanism, and solving the problem of noise caused by limited performance and insufficient rigidity.

[0068] Optional, continue to refer to Figure 1 , Figure 2 and Figure 3 As shown, it also includes a spindle motor 3, a spindle cam assembly 5, a slide 7, and a slider 8;

[0069] The needle bar 10 and the main shaft cam assembly 5 are fixedly connected to the slider 8 respectively; the slide groove 7 is fixed on the housing 1 and slidably connected to the slider 8; the main shaft cam assembly 5 is fixedly connected to the main shaft motor 3.

[0070] The control unit 2 is electrically connected to the spindle motor 3 and is used to control the rotation of the spindle motor 3 so as to drive the needle bar 10 to move in the first direction.

[0071] The main spindle cam assembly 5 is fixedly connected to the main spindle motor 3, which drives the main spindle cam assembly 5 to rotate. The main spindle cam assembly 5 is fixedly connected to the slider 8. In some embodiments, the main spindle cam assembly 5 can be fixedly connected to the slider 8 via a balance assembly 6, and the rotation of the main spindle cam assembly 5 drives the slider 8 to reciprocate along a first direction. The needle bar 10 and the slider 8 can be connected via a needle bar retainer 9, and the slider 8 moves along the first direction in the slide groove 7, thereby driving the needle bar 10 to reciprocate along the first direction to achieve sewing.

[0072] The control unit 2 is electrically connected to the spindle motor 3 and can control the rotation speed and direction of the spindle motor 3, thereby driving the needle bar 10 to reciprocate along the first direction.

[0073] The technical solution of this invention realizes the motion control of the needle bar 10 by setting up a spindle motor 3, a spindle cam assembly 5, a slide groove 7 and a slider 8.

[0074] Optional, continue to refer to Figure 1 , Figure 2 and Figure 3 As shown, it also includes a current detection unit 4; the current detection unit 4 is used to detect the load current of the spindle motor 3.

[0075] The control unit 2 is electrically connected to the current detection unit 4 and is used to acquire the load current and control the running speed of the upper feed wheel motor 14 and the running speed of the lower feed wheel motor 17 according to the load current.

[0076] The current detection unit 4 can be used to detect the load current of the spindle motor 3. The load current is the current that the spindle motor 3 carries when driving the mechanical load during actual operation. The load current can represent the actual size of the load currently being carried. When the needle 13 is in the piercing stage, it will cause periodic load current peaks. Therefore, by detecting the load current, it can be determined whether the needle 13 is currently in the piercing stage. When the needle 13 is in the piercing stage, due to the existence of resistance, if the upper feed wheel motor 14 and the lower feed wheel motor 17 keep their speeds constant, the feeding amount will deviate. Therefore, the load current can be used to determine whether it is in the piercing stage. If it is in the piercing stage, the running speeds of the upper feed wheel motor 14 and the lower feed wheel motor 17 are corrected to compensate for the deviation in the feeding amount.

[0077] In some embodiments, the output torque of the spindle motor 3 can be controlled by detecting the load current to identify the piercing and non-piercing stages. High torque output is provided during the piercing stage to ensure penetration, while torque is reduced during the non-piercing stage to optimize energy consumption and reduce heat generation.

[0078] Understandably, through the detection of the current detection unit, the control unit can dynamically compensate the running speed of the upper feed wheel motor 14 and the lower feed wheel motor 17, thereby correcting the potential feeding deviation caused by the cancellation of the needle pendulum feeding.

[0079] The technical solution of this invention, by setting a current detection unit, allows the control unit to adjust the running speed of the upper feed wheel motor and the lower feed wheel motor according to the load current, thereby ensuring the accuracy of the feeding amount.

[0080] Optional, continue to refer to Figure 1 , Figure 2 and Figure 3 As shown, it also includes a presser foot lifting motor 18, a presser foot lifting cam 19, a presser foot pressure cam 20, a presser foot lifting crank mechanism 24, a presser foot pressure mechanism 23, a presser foot bar mechanism 21, and a thickness detection component 26;

[0081] The presser foot lifting motor 18 is fixedly connected to the presser foot lifting cam 19 and the presser foot pressure cam 20 respectively; the presser foot lifting cam 19 is fixedly connected to the presser foot bar mechanism 21 through the presser foot lifting crank mechanism 24; the presser foot pressure cam 20 is connected to the presser foot bar mechanism 21 through the presser foot pressure mechanism 23; the presser foot bar mechanism 21 is fixedly connected to the upper feed wheel assembly 15 and the thickness detection assembly 26 respectively.

[0082] The control unit 2 is electrically connected to the lifting foot motor 18 and is used to acquire the thickness signal of the thickness detection component 26 and control the lifting foot motor 18 to rotate forward or backward according to the thickness signal.

[0083] The foot-lifting motor 18 is fixedly connected to the foot-lifting cam 19. The foot-lifting cam 19 is fixedly connected to the foot-lifting crank mechanism 24 and the foot-lifting rod mechanism 21. The foot-lifting rod mechanism 21 is fixedly connected to the upper feed wheel assembly 15. When the foot-lifting motor 18 rotates forward, the foot-lifting cam 19 drives the foot-lifting crank mechanism 24, which in turn drives the foot-lifting rod mechanism 21 to move upward, causing the upper feed wheel assembly 15 to move upward and lift the foot. The foot-lifting motor 18 is fixedly connected to the foot-lifting pressure cam 20. The foot-lifting pressure cam 20 is connected to the foot-lifting rod through the foot-lifting pressure mechanism 23. When the foot-lifting motor 18 rotates in reverse, it drives the foot-lifting pressure cam 20 to rotate, which in turn drives the upper feed wheel assembly 15 to move downward and lift the foot to apply pressure.

[0084] The thickness detection component 26 is mounted on the presser foot mechanism 21. The thickness detection component 26 may include a Hall element and a magnetic element. The magnetic element is mounted on the presser foot mechanism 21, and the Hall element is mounted on the housing 1. The Hall element generates a thickness signal by monitoring the up and down movement of the magnetic component. The thickness signal reflects the thickness of the seam material.

[0085] Specifically, when the thickness signal is greater than the preset thickness, it means that the fabric is thick. At this time, the presser foot motor 18 can be reversed to increase the pressure of the presser foot on the fabric, ensuring sufficient clamping force under thick material conditions and preventing the upper fabric from slipping.

[0086] In some embodiments, the static friction between the teeth of the upper feed gear and the sewing fabric may be set to be greater than or equal to the feed resistance that needs to be overcome when sewing fabric of the maximum permissible thickness.

[0087] The technical solution of this invention, by setting up a presser foot motor, a presser foot cam, a presser foot pressure cam, a presser foot crank mechanism, a presser foot pressure mechanism, a presser foot bar mechanism, and a thickness detection component, achieves thickness detection and adaptive adjustment of presser foot pressure, thereby realizing precise control of the upper layer of sewing material.

[0088] The technical solution of this invention achieves the following effects:

[0089] Cost reduction and structural simplification: The entire set of high-cost and easily worn complex mechanical mechanisms, such as the pin pendulum motor, connecting rod, and oscillating pin bar seat, has been completely eliminated, achieving a significant reduction in hardware costs and extreme simplification of the overall structure, while simultaneously improving assembly efficiency and reliability.

[0090] Performance Improvement: Abandoning the inefficient "needle-and-cloth" mode, the new paradigm of "precise coordinated differential feeding of upper and lower wheels" is adopted. Based on the four-segment timing control triggered by the main shaft angle and the S-curve acceleration and deceleration, more precise and gentle anti-misalignment layer control is achieved, resulting in better stitch quality and wider fabric adaptability.

[0091] Intelligent and adaptive capabilities: By introducing thickness detection and active pressure control, as well as load-based feeding compensation, the column sewing machine is equipped with the ability to sense the environment and adapt to changes, achieving a leap from "passive mechanical execution" to "active intelligent control".

[0092] Based on the same inventive concept. Figure 4 This is a flowchart of a control method for a first type of column sewing machine according to an embodiment of the present invention, combined with... Figures 1 to 4 As shown, this embodiment of the invention provides a control method for a column sewing machine, applied in a column sewing machine; the control method includes:

[0093] S10, Obtain the position of the needle bar movement.

[0094] The position of the needle bar movement can represent the distance between the needle 13 and the sewing material. The feeding speed is determined by the distance between the needle 13 and the sewing material, thereby controlling the speed of the upper feeding wheel motor 14 and the lower feeding wheel motor 17.

[0095] S11. Control the upper feed wheel motor to run at the first speed and the lower feed wheel motor to run at the second speed according to the position of the needle bar.

[0096] Among them, the first speed and the second speed represent the speed during the operation process. That is, the first speed and the second speed are not constant values ​​and can change according to the position of the needle bar.

[0097] Specifically, the needle bar position is first obtained, the distance between the needle 13 and the sewing material is determined based on the needle bar position, and then the upper feed wheel motor 14 is controlled to run at the first speed, and the lower feed wheel motor 17 is controlled to run at the second speed to feed the material.

[0098] The technical solution of this invention eliminates the needle pendulum feeding mechanism and achieves feeding by controlling the upper feeding wheel motor and the lower feeding wheel motor, thus ensuring the normal operation of the column sewing machine.

[0099] Based on the above embodiments, Figure 5 This is a flowchart of a control method for a second type of column sewing machine according to an embodiment of the present invention, combined with... Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, the column sewing machine also includes a main spindle motor 3, a main spindle cam assembly 5, a slide 7, and a slider 8; the first speed includes a first-stage speed, a second-stage speed, a third-stage speed, and a fourth-stage speed. The second speed includes a fifth-stage speed, a sixth-stage speed, a seventh-stage speed, and an eighth-stage speed; the encoder angle of the main spindle motor 3 determines the needle bar movement position.

[0100] The control method includes:

[0101] S20, Obtain the position of the needle bar movement.

[0102] S21. Obtain the encoder angle.

[0103] Since the main spindle motor 3 drives the needle bar 10 to move up and down reciprocally, the encoder angle of the main spindle motor 3 can reflect the position of the needle bar, that is, the distance between the needle bar 10 and the sewing material.

[0104] S22. When the encoder angle is equal to the first preset angle, control the upper feed wheel motor to run at the first stage speed and control the lower feed wheel motor to run at the fifth stage speed.

[0105] Among them, the first preset angle This refers to the encoder angle corresponding to the first height reached when the needle 13 leaves the fabric. In the first stage speed, the acceleration of the upper feed wheel increases from 0 to 'a'; in the fifth stage speed, the acceleration of the lower feed wheel increases from 0 to 'b'; where 'a' > 0 and is a constant; and 'b' > 0 and is a constant. When the encoder angle equals the first preset angle, it indicates that the needle 13 has left the fabric and reached the first height. At this point, the upper feed wheel motor 14 is controlled to run at the first stage speed, and the lower feed wheel motor 17 is controlled to run at the fifth stage speed. That is, the acceleration of the upper feed wheel motor 14 and the lower feed wheel motor 17 continuously increases. The process of increasing from 0 to 'a' and from 0 to 'b' can be an S-shaped curve, thus making the acceleration rise smoothly without any impact peaks, reducing stepper tooth vibration, decreasing feeding start-up noise, and significantly improving machine head vibration. In actual operation, this stage can complete 10-20% of the total feeding volume.

[0106] S23. When the encoder angle is equal to the second preset angle, control the upper feed wheel motor to run at the second stage speed and control the lower feed wheel motor to run at the sixth stage speed.

[0107] Among them, the second preset angle This is the encoder angle corresponding to the second height from which the needle 13 leaves the fabric. The second height can be the maximum high speed that the needle 13 can reach. In the second stage speed, the acceleration of the upper feed roller is 0; in the sixth stage speed, the acceleration of the lower feed roller is 0. The encoder angle is equal to the second preset angle. When the speed reaches 13, it indicates that the needle 13 has reached its second high speed, and therefore operates at a constant speed. In actual operation, this stage can complete 65-75% of the total feed volume, with speed stability ≤ ±1.5%.

[0108] S24. When the encoder angle is equal to the third preset angle, control the upper feed wheel motor to run at the third stage speed and control the lower feed wheel motor to run at the seventh stage speed.

[0109] Among them, the third preset angle The encoder angle corresponds to the third height when the needle 13 approaches the sewing material, at which point the needle 13 moves downwards from the second height. In the third stage of speed, the acceleration of the upper feed wheel decreases from 0 to c; in the seventh stage of speed, the acceleration of the lower feed wheel decreases from 0 to d; where c < 0 and is a constant; d < 0 and is a constant. When the encoder angle equals the third preset angle, it indicates that the needle 13 has moved downwards to the third height, the deceleration smoothly increases from 0 to c, there is no braking impact, the stepper tooth vibration is reduced, and the stop is smooth. In actual operation, this stage can complete 15-25% of the total feed volume.

[0110] S25. When the encoder angle is equal to the fourth preset angle, control the upper feed wheel motor to run at the fourth stage speed and control the lower feed wheel motor to run at the eighth stage speed.

[0111] Among them, the fourth preset angle The encoder angle corresponds to the fourth height at which the needle 13 approaches the fabric. The third height is greater than the fourth height, and the fourth height is the height at which the needle is closer to the fabric. In the fourth stage speed, the acceleration of the upper feed wheel is e; in the eighth stage speed, the acceleration of the lower feed wheel is f; where e and f are constants. When the encoder angle equals the fourth preset angle, to prevent fabric deviation caused by inertia, the speeds of the upper feed wheel motor 14 and the lower feed wheel motor 17 can be controlled, either by decreasing or increasing the speed. In some embodiments, the fine-tuning amount is 0.1-0.3 mm, and the feed endpoint accuracy is ±0.05 mm.

[0112] The technical solution of this invention adopts a four-stage trigger feeding system, which reduces vibration and noise, improves the stability of the column sewing machine during operation, achieves precise stop control, and ensures sewing quality.

[0113] Based on the above embodiments, Figure 6 This is a flowchart of a control method for a third type of column sewing machine according to an embodiment of the present invention, combined with... Figure 1 , Figure 2 , Figure 3 and Figure 6 As shown, the column sewing machine also includes a current detection unit 4. The control method includes:

[0114] S30, Obtain the position of the needle bar movement.

[0115] S31. Obtain encoder angle.

[0116] S32. When the encoder angle is equal to the first preset angle, control the upper feed wheel motor to run at the first stage speed and control the lower feed wheel motor to run at the fifth stage speed.

[0117] S33. When the encoder angle is equal to the second preset angle, control the upper feed wheel motor to run at the second stage speed and control the lower feed wheel motor to run at the sixth stage speed.

[0118] S34. Obtain the load current.

[0119] Among them, the load current can be the current that the spindle motor passes through when driving the mechanical load during actual operation.

[0120] S35. Determine the rate of change of current based on the load current.

[0121] Among them, the current change rate can characterize whether a load current peak occurs, and thus detect whether the current needle 13 is in the piercing stage.

[0122] S36. Correct the running speed of the upper feed wheel motor and the running speed of the lower feed wheel motor according to the rate of change of current.

[0123] When the needle 13 is in the needle-punching stage, if the upper feed wheel motor 14 and the lower feed wheel motor 17 keep their speeds constant due to the resistance, the feed amount will deviate and the load current will suddenly increase. Therefore, the load current can be used to determine whether it is in the needle-punching stage. If it is in the needle-punching stage, the running speed of the upper feed wheel motor 14 and the running speed of the lower feed wheel motor 17 should be corrected to compensate for the deviation in the feed amount.

[0124] S37. When the encoder angle is equal to the third preset angle, control the upper feed wheel motor to run at the third stage speed and control the lower feed wheel motor to run at the seventh stage speed.

[0125] S38. When the encoder angle is equal to the fourth preset angle, control the upper feed wheel motor to run at the fourth stage speed and control the lower feed wheel motor to run at the eighth stage speed.

[0126] Based on the above embodiments, Figure 7 This is a flowchart of a control method for a fourth type of column sewing machine according to an embodiment of the present invention, combined with... Figure 1 , Figure 2 , Figure 3 and Figure 7 As shown, the column sewing machine also includes a current detection unit 4. The control method includes:

[0127] S40, Obtain the position of the needle bar movement.

[0128] S41. Obtain encoder angle.

[0129] S42. When the encoder angle is equal to the first preset angle, control the upper feed wheel motor to run at the first stage speed and control the lower feed wheel motor to run at the fifth stage speed.

[0130] S43. When the encoder angle is equal to the second preset angle, control the upper feed wheel motor to run at the second stage speed and control the lower feed wheel motor to run at the sixth stage speed.

[0131] S44. Obtain the load current.

[0132] S45. Determine the rate of change of current based on the load current.

[0133] S46. When the rate of change of current is greater than the preset rate of change, correct the running speed of the upper feed wheel motor and the running speed of the lower feed wheel motor.

[0134] When the rate of change of current is greater than the preset rate of change, it indicates that a sudden increase in load current has occurred and the needle-punching stage has begun. The running speed of the upper feed wheel motor 14 and the running speed of the lower feed wheel motor 17 are corrected to correct the potential feeding deviation caused by the cancellation of needle pendulum feeding.

[0135] S47. When the encoder angle is equal to the third preset angle, control the upper feed wheel motor to run at the third stage speed and control the lower feed wheel motor to run at the seventh stage speed.

[0136] S48. When the encoder angle is equal to the fourth preset angle, control the upper feed wheel motor to run at the fourth stage speed and control the lower feed wheel motor to run at the eighth stage speed.

[0137] Based on the above embodiments, Figure 8 This is a flowchart of a fifth type of control method for a column sewing machine according to an embodiment of the present invention, combined with... Figure 1 , Figure 2 , Figure 3 and Figure 8 As shown, the column sewing machine also includes a presser foot lifting motor 18, a presser foot lifting cam 19, a presser foot pressure cam 20, a presser foot lifting crank mechanism 24, a presser foot pressure mechanism 23, a presser foot bar mechanism 21, and a thickness detection component 26. The control method includes:

[0138] S50, Obtain the position of the needle bar movement.

[0139] S51. Control the upper feed wheel motor to run at the first speed and the lower feed wheel motor to run at the second speed according to the needle bar movement position.

[0140] S52. Obtain the thickness signal from the thickness detection component.

[0141] S53. Control the forward or reverse rotation angle of the lifting foot motor according to the thickness signal.

[0142] Specifically, when the thickness signal is greater than the preset thickness, it indicates that the fabric is too thick. In this case, the presser foot motor 18 can be reversed to increase the pressure of the presser foot on the fabric, ensuring sufficient clamping force for thick fabrics and preventing the upper fabric from slipping. The reversal angle can be determined based on the difference between the thickness signal and the preset thickness, thus ensuring accurate pressure adjustment.

[0143] The technical solution of this invention realizes the adaptive adjustment of thickness detection and presser foot pressure, thereby achieving precise control of the upper layer of seam material.

[0144] The technical solution of this invention achieves the following effects:

[0145] Feeding accuracy has been greatly improved: the creep rate has been reduced from 0.5% in the traditional pinwheel feeding solution to less than 0.25%;

[0146] System vibration is significantly reduced: S-curve control reduces overall machine vibration and noise.

[0147] Enhanced fabric adaptability: Enables fine sewing across a full range of materials, from thin to thick, through thickness self-adaptation;

[0148] Precise pressure control: Selective pressure application avoids excessive compression of the underlying fabric, improving sewing quality;

[0149] Significant energy consumption optimization: Intelligent acceleration and deceleration control reduces system energy consumption by more than 30%;

[0150] Significantly improved reliability: The easily damaged needle pendulum mechanism has been eliminated, extending the overall maintenance cycle and improving the service life of the machine.

[0151] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0152] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A column sewing machine, characterized in that, include: Machine housing, needle bar, needle, upper feed wheel assembly, upper feed wheel motor, lower feed wheel assembly, lower feed wheel motor and control unit; The needle is fixed to one end of the needle bar; The control unit is electrically connected to the upper feed wheel motor and the lower feed wheel motor respectively; the upper feed wheel motor is fixedly connected to the upper feed wheel assembly, and the lower feed wheel motor is fixedly connected to the lower feed wheel assembly; the control unit is used to control the upper feed wheel motor to run at a first speed and control the lower feed wheel motor to run at a second speed according to the needle bar movement position. During operation, the upper feed wheel assembly and the lower feed wheel assembly are used to clamp and move the sewing material; the needle bar is used to move only along a first direction to sew the sewing material; wherein, the first direction is the extension direction of the needle bar.

2. The column sewing machine according to claim 1, characterized in that, Also includes: upper guide sleeve and lower guide sleeve of needle bar; The upper guide sleeve and the lower guide sleeve of the needle bar are both fixedly mounted on the machine housing and are both sleeved on the needle bar; the first direction includes the direction from the upper guide sleeve of the needle bar to the lower guide sleeve of the needle bar and the direction from the lower guide sleeve of the needle bar to the upper guide sleeve of the needle bar.

3. The column sewing machine according to claim 1, characterized in that, It also includes a spindle motor, a spindle cam assembly, a slide rail, and a slider; The needle bar and the main spindle cam assembly are respectively fixedly connected to the slider; the slide groove is fixed to the machine housing and slidably connected to the slider; the main spindle cam assembly is fixedly connected to the main spindle motor; The control unit is electrically connected to the spindle motor and is used to control the spindle motor to rotate, thereby driving the needle bar to move along the first direction.

4. The column sewing machine according to claim 3, characterized in that, It also includes a current detection unit; the current detection unit is used to detect the load current of the spindle motor; The control unit is electrically connected to the current detection unit and is used to acquire the load current and control the running speed of the upper feed wheel motor and the running speed of the lower feed wheel motor according to the load current.

5. The column sewing machine according to claim 1, characterized in that, It also includes a presser foot lifting motor, a presser foot lifting cam, a presser foot pressure cam, a presser foot lifting crank mechanism, a presser foot pressure mechanism, a presser foot bar mechanism, and a thickness detection component; The presser foot lifting motor is fixedly connected to the presser foot lifting cam and the presser foot pressure cam respectively; the presser foot lifting cam is fixedly connected to the presser foot bar mechanism through the presser foot lifting crank mechanism; the presser foot pressure cam is connected to the presser foot bar mechanism through the presser foot pressure mechanism; the presser foot bar mechanism is fixedly connected to the upper feed wheel assembly and the thickness detection assembly respectively; The control unit is electrically connected to the lifting foot motor and is used to acquire the thickness signal of the thickness detection component and control the forward or reverse rotation angle of the lifting foot motor according to the thickness signal.

6. A control method for a column sewing machine, characterized in that, Applied in the column sewing machine according to any one of claims 1-5; The control method includes: Obtain the position of the needle bar movement; The upper feed wheel motor is controlled to run at a first speed and the lower feed wheel motor is controlled to run at a second speed based on the position of the needle bar.

7. The control method according to claim 6, characterized in that, The column sewing machine also includes a main spindle motor, a main spindle cam assembly, a slide rail, and a slider; the first speed includes a first-stage speed, a second-stage speed, a third-stage speed, and a fourth-stage speed; the second speed includes a fifth-stage speed, a sixth-stage speed, a seventh-stage speed, and an eighth-stage speed; the encoder angle of the main spindle motor determines the needle bar movement position; Controlling the upper feed wheel motor to run at a first speed and the lower feed wheel motor to run at a second speed according to the needle bar's movement position includes: Obtain the encoder angle; When the encoder angle is equal to the first preset angle, the upper feed wheel motor is controlled to run at the first stage speed, and the lower feed wheel motor is controlled to run at the fifth stage speed. When the encoder angle is equal to the second preset angle, the upper feed wheel motor is controlled to run at the second stage speed, and the lower feed wheel motor is controlled to run at the sixth stage speed. When the encoder angle is equal to the third preset angle, the upper feed wheel motor is controlled to run at the third stage speed, and the lower feed wheel motor is controlled to run at the seventh stage speed. When the encoder angle is equal to the fourth preset angle, the upper feed wheel motor is controlled to run at the fourth stage speed, and the lower feed wheel motor is controlled to run at the eighth stage speed.

8. The control method according to claim 7, characterized in that, The first preset angle is the encoder angle corresponding to the first height from which the needle leaves the sewing material; in the first stage speed, the acceleration of the upper feed wheel increases from 0 to a; in the fifth stage speed, the acceleration of the lower feed wheel increases from 0 to b; where a > 0 and is a constant; b > 0 and is a constant; The second preset angle is the encoder angle corresponding to the second height from which the needle leaves the sewing material; the acceleration of the upper feed wheel is 0 in the second stage speed; the acceleration of the lower feed wheel is 0 in the sixth stage speed; The third preset angle is the encoder angle corresponding to the third height to which the needle approaches the sewing material; in the third stage speed, the acceleration of the upper feed wheel decreases from 0 to c; in the seventh stage speed, the acceleration of the lower feed wheel decreases from 0 to d; where c < 0 and is a constant; d < 0 and is a constant; The fourth preset angle is the encoder angle corresponding to the fourth height to which the needle approaches the sewing material; the acceleration of the upper feed wheel in the fourth stage speed is e; the acceleration of the lower feed wheel in the eighth stage speed is f; where e is a constant; f is a constant; Wherein, the second height is greater than the first height; the third height is greater than the fourth height.

9. The control method according to claim 6, characterized in that, The column sewing machine also includes a presser foot lifting motor, a presser foot lifting cam, a presser foot pressure cam, a presser foot lifting crank mechanism, a presser foot pressure mechanism, a presser foot bar mechanism, and a thickness detection component; After controlling the upper feed wheel motor to run at a first speed and the lower feed wheel motor to run at a second speed according to the needle bar's movement position, the method further includes: Obtain the thickness signal from the thickness detection component; The forward or reverse rotation angle of the lifting foot motor is controlled according to the thickness signal.

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