JP2008086350A - Presser foot lifting device of sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a presser foot lifting device of a sewing machine, which has improved operability and usability for a secured high performance. <P>SOLUTION: The presser foot lifting device includes operation means 13, an actuator 9 driven by operation input by the operation means 13, driving force-transmitting means 10 for vertically moving a presser bar 2 by the driving force of the actuator 9, operation amount-detecting means 14 for detecting an operation amount of the operation means 13, cloth thickness-detecting means 12 for detecting the thickness t of a cloth T to be sewn for sewing, and control means 11 for controlling the operation of any part of the sewing machine. The control means 11 is provided with an operation control portion 20 for the presser foot, which calculates the height position of a presser foot 4 by a first lifting position-setting means 18 and drives and controls the actuator 9 so as to be positioned at a first lifting position stored in a fixed value-storing portion 17, when an operation position-determining portion 19 determines that the operation position of the operation means 13 is at the first lifting position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a presser lifting device for a sewing machine, and more particularly to a presser lifting device for a sewing machine suitable for controlling the height position of a presser foot based on an operation amount of an operating means.

  2. Description of the Related Art Conventionally, in a sewing machine, a presser that moves up and down a cloth presser that holds a cloth to be sewn at a desired position on a bed from above with an appropriate pressure, specifically, a top surface of a needle drop hole of a throat plate arranged on the bed. A lifting device is provided.

  As a presser lifting device for such a sewing machine (mainly industrial sewing machine), the height position of the presser foot from the bed is detected, and the presser foot is further raised by the presser foot lifting signal based on the detected position. In order to improve the operability such as positioning, rotation, and attachment / detachment of the cloth to be sewn, there has been proposed (for example, see Patent Document 1).

  In addition, there has been proposed a technique that finely adjusts the height position of the presser foot from the bed steplessly in accordance with the stepping amount (operation amount) of the foot pedal by moving the presser foot up and down with an electric actuator ( For example, see Patent Document 2).

JP-A-62-120884 (FIG. 1) JP 2001-149681 A (FIG. 8)

  However, the conventional sewing machine presser lifting device has a problem that it cannot meet the recent demand for higher performance.

  That is, in the conventional presser foot lifting device that further raises the presser foot according to the presser foot lift signal, since the lift amount of the presser foot is a constant amount, the positioning of the sewing target fabric, that is, with respect to the sewing target fabric. Although it is easy to align the needle drop position at the beginning of sewing, it is not suitable for changing the direction of the seam of thick materials such as jeans and stepped stitches at the folded back of the hem and the cloth to be sewn. There was a point.

  In addition, in a conventional presser lifting device for a sewing machine that is configured to finely adjust the height position of the presser foot from the bed steplessly, linearly so that the height of the presser foot from the bed and the operation amount increase with each other. Because it is proportional, it is difficult to keep the height of the presser foot from the bed at a fixed position, and the presser foot is large when pressing the presser foot with the cloth to be sewn placed on the sewing machine bed. There was a problem that the operation intended by the operator who wanted to move up quickly with the amount of movement could not be executed.

  Accordingly, there is a need for a presser device for a sewing machine that can reliably improve performance by improving operability and usability.

  The present invention has been made in view of this point, and an object of the present invention is to provide a sewing machine presser lifting device capable of surely improving performance by improving operability and usability.

  In order to achieve the above-described object, the presser lifting device for a sewing machine according to the present invention is attached to the lower end portion of a presser bar supported by an arm so as to be movable up and down in order to press the cloth to be sewn against the bed. In the presser lifting device of the sewing machine in which the presser foot is in contact with and separated from the bed, an operation means for performing an operation input for making the presser foot contact and separate, an actuator driven by the operation input of the operation means, Driving force transmission means for moving the presser bar up and down by the driving force of the actuator, operation amount detection means for detecting the operation amount of the operation means, and cloth thickness detection for detecting the thickness of the cloth to be sewn for sewing And control means for controlling the operation of each part of the sewing machine. The control means aligns the cloth to be sewn that is used for sewing the cloth presser on the bed. Receiving a fixed value storage unit in which a fixed value used for moving to the first ascending position is stored in advance, and a detection signal of the thickness of the sewing object cloth sent from the cloth thickness detecting means, The fixed value stored in the fixed value storage unit is added to the thickness of the cloth, and the height position from the bed that is the first raised position of the cloth presser corresponding to the cloth to be sewn for sewing is calculated. Based on the first ascending position setting unit stored and the operation amount of the operation means sent out from the operation amount detection means, at least the cloth presser is placed on the bed with the operation position of the operation means. An operation position determination unit that performs multi-step determination so as to include an initial position that presses the surface of the cloth to be sewn and the first lift position, and at least the operation position determination unit raises the operation position of the operation means to the first rise If it is determined as the position, And a presser foot lifting operation control unit that drives and controls the actuator so that the height position of the presser is the first lift position calculated and stored by the first lift position setting hand unit. . And by employ | adopting such a structure, the 1st raise position of the cloth presser suitable for position alignment of the sewing object cloth can be controlled for every sewing object cloth used for sewing.

  According to the presser lifting device for a sewing machine according to the present invention, it is possible to control the first lifting position of the presser foot suitable for positioning of the sewing target cloth for each sewing target cloth to be used for sewing. As a result, there are excellent effects such as reliable improvement in operability and usability.

  The present invention will be described below with reference to embodiments shown in the drawings.

  FIG. 1 is a schematic view showing a main part of an embodiment of a sewing machine presser lifting apparatus according to the present invention in a simplified manner.

  As shown in FIG. 1, a presser lifting device 1 (hereinafter simply referred to as a presser lifting device) for a sewing machine according to this embodiment includes a presser bar 2. The presser bar 2 is supported by a pair of upper and lower presser bar bearings (not shown) disposed at the free end of the arm 3 so as to be vertically movable and reciprocally movable in the vertical direction. Further, the lower part of the presser bar 2 protrudes below the arm 3 and is exposed to the outside, and the presser foot 4 is detachably attached to the lower end part of the presser bar 2. The cloth presser 4 has a bed 5 on which the cloth T to be sewn (FIG. 3) is always placed by a biasing force of a biasing spring (not shown) disposed on the upper part of the presser bar 2, more specifically, a needle on the upper surface of the bed 5. It is urged and brought into contact with a needle plate (not shown) provided at the dropping position.

  In the sewing machine, the frame of the sewing machine body includes a bed 5, an arm 3 extending above the bed 5 in parallel with the bed 5, and the bed 5 and the arm 3 opposite to the free end side of the arm 3. It is formed in a substantially U shape having a connecting body portion connected on the base end side. Moreover, it is common for the sewing machine used for industrial use that the sewing machine main body is mounted on the sewing machine table.

  In addition, as the sewing target cloth T, various cloths that are sewn by a sewing machine such as leather can be used.

  A base portion of the presser bar holder 6 is detachably attached to a longitudinal intermediate portion of the presser bar 2 located inside the arm 3 by a set screw (not shown). The front end portion of the presser bar holder 6 protrudes in the horizontal direction toward the right in FIG. 1, which is orthogonal to the axial direction of the presser bar 2. The upper surface of the drive arm 7a, which is one arm of a presser lifter lever 7 formed in a substantially bell crank shape for moving 2 up and down, is disposed so as to be able to contact and separate from below. The drive arm 7a is disposed inside the arm 3 with its longitudinal direction substantially horizontal.

  As exaggeratedly shown in FIG. 1, the drive arm 7a includes a state in which the cloth presser 4 is in contact with the bed 5 (including a state in which the cloth presser 4 is in contact with the bed 5 via the sewing target cloth T in the sewing state). ) Is separated from the presser bar hanger 6 with a predetermined gap. Thereby, in the sewing state, the cloth presser 4 can move up and down following the change in the thickness of the sewing target cloth T with the urging force of the urging spring held.

  A through hole 7c penetrating in the thickness direction is formed in the central portion of the bent portion of the presser lever 7 and the tip of a support shaft (not shown) inserted through the through hole 7c is connected to the inside of the arm 3. By being screwed onto the arm 3, the arm 3 is pivotably attached to the support shaft as shown by an arcuate double arrow in FIG. The other arm of the lifting lever 7 is a driven arm 3b, and this driven arm 3b is disposed inside the sewing machine arm 3 with its longitudinal direction substantially vertical. A driving force of an actuator 9 such as a servo motor is transmitted to the free end portion of the driven arm 3b via the link mechanism 8.

  The presser bar holder 6, the presser lifting lever 7 and the link mechanism 8 constitute drive force transmitting means 10 for moving the presser bar 2 up and down by the driving force of the actuator 9 of this embodiment.

  The driving force transmitting means 10 may be any means that moves the presser bar 2 up and down by the driving force of the actuator 9, and can be selected from various conventionally known configurations. The actuator 9 can be selected from various types in which the output shaft rotates, swings and reciprocates by electric, pneumatic, hydraulic, etc., but an electric actuator in which the output shaft rotates or reciprocates by electric is generally used. Has been used.

  The actuator 9 is electrically connected to a control means 11 described later, and is driven and controlled at a predetermined timing based on a control command sent from the control means 11.

  The presser foot lifting device 1 of the present embodiment is provided with a cloth thickness detecting means 12 for detecting the thickness of the sewing target cloth T to be used for sewing. The cloth thickness detection means 12 is electrically connected to the control means 11 described later so that a detection signal of the detected thickness t (mm) of the sewing target cloth T can be sent to the control means 11. It has become.

  The cloth thickness detecting means 12 can be selected from conventionally known various types. For example, a position sensor (magnetism, photo, potention, etc.) disposed inside the arm 3 can be used.

  The presser foot lifting device 1 of the present embodiment is provided with operating means 13 for moving the presser foot 4 so as to move up and down. As the operation means 13, for example, a knee lifter operated by a knee, an operator operating with a foot, or a stepping operation pedal operated by a foot is used alone or in combination. Then, the presser foot 4 can be brought into and out of contact with the bed 5 by operating the operating means.

  The operation means 13 is connected to an operation amount detection means 14 such as a potentiometer for detecting the operation amount. The operation amount detection means 14 is electrically connected to the control means 11 described later, and can send an operation amount detection signal when the operator operates the operation means 13 to the control means 11. ing.

  The control means 11 includes at least a CPU 15 and a memory 16 formed by a ROM, RAM, or the like having an appropriate capacity.

  The memory 16 includes at least a fixed value storage unit 17, a first raised position setting unit 18, an operation position determination unit 19, and a presser lifting operation control unit 20.

  The fixed value storage unit 17 stores in advance a fixed value α (mm) used for moving the cloth presser 4 to the first ascending position for positioning the sewing target cloth T used for sewing on the bed 5. Has been.

  The first raising position setting unit 18 receives the detection signal of the thickness t of the sewing target cloth T sent from the cloth thickness detecting means 12, and stores the thickness t of the sewing target cloth T in the fixed value storage unit 17. The stored fixed value α is added to calculate and store the height position H2 (FIG. 3) from the bed 5 which is the first ascending position of the presser foot 4 corresponding to the sewing target cloth T to be used for sewing. The program is stored. In addition, as a memory | storage part of the height position H2 from the bed 5 used as the 1st raising position of the calculated presser foot 4, from the arbitrary parts of the memory 16 containing the fixed value memory | storage part 17, according to the necessity of a design concept etc. Can be set.

  The operation position discriminating unit 19 determines the operation position of the operation unit 13 based on the operation amount of the operation unit 13 sent from the operation amount detection unit 14, at least the sewing object on which the presser foot 4 is placed on the bed 5. An initial position for pressing the surface of the cloth T, and a first raised position and a first raised position for aligning a cloth to be sewn that is provided adjacent to the initial position and is used for sewing on the bed 5 A program for multi-stage discrimination is stored so as to include.

  In the presser foot lifting control unit 20, the height position of the presser foot 4 is calculated by the first lift position setting unit 18 when at least the operation position determination unit 19 determines that the operation position of the operation means 13 is the first lift position. A program for driving and controlling the actuator 9 so as to be in the first ascending position stored in the memory 16 is stored.

  The control means 11 is connected to various switches, sensors, sewing machine motors and the like for controlling sewing operations such as a sewing machine power switch and a sewing start switch.

  The memory 16 also stores a program for controlling the operation and operation sequence of each part when executing the sewing operation, a program for performing an initialization operation when the power is turned on, and various kinds of operations necessary for executing the sewing operation and the presser foot lifting operation. Data and programs are stored.

  Here, an example of the relationship between the height position of the presser foot 4 from the bed 5 and the operation position by the operation means 13 in the presser lifting device 1 of the present embodiment will be described.

  FIG. 2 is an explanatory view showing an example of a multi-stage division of the operation amount in the embodiment of the sewing machine presser lifting apparatus according to the present invention.

  In the presser foot lifting device 1 of the present embodiment, the height position of the presser foot 4 from the bed 5, specifically the needle plate (hereinafter simply referred to as the height position), is made to correspond to the operation amount of the operating means 13. It is configured to be divided into a plurality of stages.

  For example, as shown in FIG. 2, the first section P1 and the second section P2 have an operation amount of the operation means 13 by the operator from zero (a state where nothing is operated) to a maximum (a state where the operator is restrained by a stopper or the like). A configuration in which the third section P3 and the fourth section P4 are divided into four sections in this order can be given.

  The first section P1 includes a play area where the operator does not operate the operation means 13 from a state where the operator does not operate the operation means 13 (including the play area of the operation means 13 itself, separated from the presser bar holder 6 with a gap). If the operating amount is within the region of the first section P1, the height position of the presser foot 4 is set on the bed 5 or sewing. It is held at an initial position in contact with the bed 5 via the target cloth T.

  The second section P2 is a section of the operation amount following the first section P1, and when the operation amount is within the region of the second section P2, for example, alignment of the sewing target cloth T used for sewing, The operation of adjusting the sewing position under the needle smoothly by moving the cloth T to be sewn for sewing placed on the bed 5 just before the start of sewing slightly along the upper surface of the bed 5 is performed smoothly and easily. Therefore, the presser foot 4 is held at the first raised position slightly raised.

  As will be described later, the first raised position is obtained by adding a preset fixed value α to the thickness t of the sewing target fabric T. The fixed value α is, for example, about 0.5 mm. It is said that. That is, the height H2 of the presser foot 4 from the bed 5 at the first raised position is a value obtained by adding a fixed value α to the thickness t of the sewing target fabric T (H2 = t + α). FIG. 3 shows a state where the presser foot 4 is positioned at the first raised position.

  The third section P3 is a section of the operation amount subsequent to the second section P2, and when the operation amount is within the region of the third section P3, for example, a step such as folding back to a part of the sewing target cloth T is performed. When there is a part or when the thickness t of the sewing target cloth T is extremely thick, the sewing target cloth T is set on the bed 5 before sewing, or the sewing target cloth T is operated to move the sewing position. The height position of the presser foot 4 is held at the second ascending position so that the stepped portion can be overcome.

  As the second raised position, for example, the height H3 of the presser foot 4 from the bed 5 is set to about 6.0 mm, and is stored in the memory 16 in advance. Of course, the second ascending position may be obtained by adding a pre-stored fixed value β (mm: β> α) to the thickness t of the sewing target fabric T. FIG. 4 shows a state where the presser foot 4 is positioned at the second raised position.

  The fourth section P4 is an operation amount section following the third section P3. When the operation amount is within the region of the fourth section P4, the direction of the sewing target cloth T is mainly changed, or the sewing target cloth is used. The height position of the presser foot 4 is held at the maximum raised position (top dead center) so that the T can be attached and detached.

  As the maximum ascending position, for example, the height H4 (H4> H3) of the presser foot 4 from the bed 5 is set to about 12.0 mm, and is stored in the memory 16 in advance. Of course, the ascending position may be obtained by adding a preset fixed value γ (mm: γ> β) to the thickness t of the sewing target fabric T. FIG. 5 shows a state where the presser foot 4 is positioned at the maximum ascending position.

  In addition, as a classification of the operation amount, as a configuration in which the height position of the presser foot 4 is divided into an initial position, a first ascending position, and a maximum ascending position according to the specifications of the sewing machine and the design concept. Alternatively, the second ascending position and the maximum ascending position may be further divided into two or more as a whole. However, if the number of sections is excessively large, it becomes almost stepless and it is not preferable because it becomes difficult for the operator to perform the operation necessary to maintain the height position of the presser foot 4 for each section.

  Further, when the operator performs an input operation of the operation means 16, at least the second, third and fourth sections P2, P3, and P4 are operated with respect to the input operation by different operation resistance (operation reaction force) or vibration. It may be configured so that feedback to the person can be performed.

  Other configurations are the same as those of the conventional presser foot lifting device, and detailed description thereof will be omitted.

  Next, the operation of the present embodiment having the above-described configuration will be described.

  FIG. 6 is a flowchart for explaining the operation of the embodiment of the sewing machine presser lifting device according to the present invention.

  The operation of the presser foot lifting device of this embodiment will be described with reference to the flowchart of FIG.

  As shown in FIG. 6, in the presser foot lifting device 1 of this embodiment, first, in step ST01, it is determined whether or not sewing is started, for example, based on the presence or absence of a sewing machine drive signal provided in the sewing machine. In the case of sewing start), the process proceeds to the next step ST02, in which the CPU 15 receives the detection signal of the thickness t of the sewing target cloth T sent from the cloth thickness detection means 12, and detects the detected thickness. The t is stored in the memory 16, and the process returns to step ST01.

  In step ST02, the CPU 15 also calculates a lower thread feeding amount for each stitch based on the thickness t of the sewing target fabric T and the feed amount of the first stitch of the sewing data necessary for forming the stitches. Various kinds of data such as going to and storing in the memory 16 are also calculated and stored in the memory 16. Thus, the preparation for the sewing operation is completed, and the sewing operation can be executed by operating a sewing start switch (not shown).

  If the determination in step ST01 is NO (not starting sewing), the process proceeds to the next step ST03, where it is determined whether or not the work clamp 4 is moved, that is, whether or not the operation amount is the first section P1. Whether or not to move the presser foot 4 is determined based on the program stored in the operation position determination unit 19 of the memory 16 by the CPU 15 based on the detection signal sent from the operation amount detection unit 14. This is done depending on whether the amount is within the range of the first section P1.

  If the determination in step ST03 is NO (do not move the presser foot 4: the operation amount is the first section P1), the process proceeds to the next step ST04, where it is determined whether or not the presser foot lifting operation is finished. In the case of YES (end), the presser foot lifting operation is ended. At this time, the presser foot 4 is held in the initial position, that is, in a state of being in contact with the bed 5 (needle plate) or in contact with the bed 5 (needle plate) through the cloth T to be sewn.

  If the determination in step ST04 is NO (not finished), the process returns to step ST01.

  If the determination in step ST03 is YES (moves the presser foot 4), the process proceeds to the next step ST05, and in the next step ST05, it is determined whether or not the operation amount is the second section P2. Whether the manipulated variable is in the second segment P2 is determined by the CPU 15 based on a program stored in the manipulated position discriminating unit 19 of the memory 16 by the detection signal sent from the manipulated variable detector 14. This is performed depending on whether the operation amount is in the second section P2. If the determination in step ST05 is YES (the operation amount is the second section P2), the process proceeds to the next step ST06.

  Next, in step ST06, the CPU 15 stores the thickness t of the sewing target fabric T stored in the memory 16 in step ST02 and the fixed value based on the program stored in the first ascending position setting unit 18 of the memory 16. In order to calculate the height H2 of the presser foot 4 at the first raised position and to set the height position of the presser foot 4 as the first raised position by reading out and adding the fixed value α stored in the portion 17. The amount of movement of the presser foot 4 necessary for the operation, more specifically, the driving amount of the actuator 9 is calculated, and the process proceeds to the next step ST07. At this time, the drive amount of the actuator 9 obtained by the calculation may be stored in the memory 16.

  Next, in step ST07, the CPU 15 drives the actuator 9 according to the driving amount of the actuator 9 obtained in step ST06 based on the program stored in the presser foot lifting operation control unit 20. As a result, the presser foot 4 is moved and held at the first raised position as shown in FIG. And if the work clamp 4 moves to a 1st raise position, it will return to step ST01.

  If the determination in step ST05 is NO (the operation amount is neither the first section P1 nor the second section P2), the process proceeds to step ST08 to determine whether the operation amount is the third section P3. Whether or not the operation amount is in the third section P3 is determined by the CPU 15 based on a program stored in the operation position determination unit 19 of the memory 16 by the detection signal sent from the operation amount detection unit 14. This is performed depending on whether or not the operation amount is in the third section P3.

  If the determination in step ST08 is YES (the operation amount is the third section P3), the process proceeds to the next step ST09, and in the next step ST09, the CPU 15 is stored in the presser foot lifting operation control unit 20. Based on the program and the height H3 of the second lift position of the presser foot 4 stored in the memory 16, the actuator 9 is driven so that the presser foot 4 moves to the second lift position. As a result, the presser foot 4 is moved to and held at the second raised position as shown in FIG. And if the work clamp 4 moves to a 2nd raise position, it will return to step ST01.

  If the determination in step ST09 is NO (the operation amount is not the first section P1, the second section P2, or the third section P3), the process proceeds to step ST10, and whether or not the operation amount is the fourth section P4. Determine (confirm). Whether the manipulated variable is in the fourth section P4 is determined by the CPU 15 based on a detection signal sent from the manipulated variable detector 14 based on a program stored in the manipulated position discriminating unit 19 of the memory 16. This is performed depending on whether or not the operation amount is in the fourth section P4.

  If the determination in step ST10 is YES (the operation amount is the fourth section P4), the process proceeds to the next step ST11, and in the next step ST11, the CPU 15 is stored in the presser foot lifting operation control unit 20. Based on the program and the height H4 of the maximum lift position of the presser foot 4 stored in the memory 16, the actuator 9 is driven so that the presser foot 4 moves to the maximum lift position. As a result, the presser foot 4 is moved to and held at the maximum raised position as shown in FIG. When the presser foot 4 moves to the maximum raised position, the process returns to step ST01.

  In addition, when obtaining the 2nd raising position and the maximum raising position of the work clamp 4 by adding fixed values β and γ set in advance to the thickness t of the sewing target cloth T, for example, steps ST09 and 11 , The movement amounts of the presser foot 4 necessary for setting the heights H3 and H4 of the presser foot 4 to the second ascending position and the ascending position, specifically, the respective driving amounts of the actuator 9 are calculated. Good.

  If the determination in step ST10 is NO (the operation amount is not the fourth section P4), the process proceeds to the next step ST12, which is preset based on the program stored in the memory 16 in the next step ST12. The operation ends, for example, an error display is performed.

  As described above, according to the presser lifting device 1 of the present embodiment, it is easy and reliable to control the first lift position of the presser foot 4 suitable for the positioning of the sewing target fabric T for each sewing target fabric T used for sewing. Can get to.

  Therefore, according to the presser foot lifting device 1 of the present embodiment, it is possible to reliably achieve high performance by improving operability and usability.

  In addition, according to the presser foot lifting device 1 of the present embodiment, the operation amount of the operating means 13 is multi-staged, specifically, the first, second, third and fourth sections P1, P2, P3, P4 are divided into four sections. Since the height position of the presser foot 4 is set for each of the four sections, the operator can easily operate the operation means 13 as compared with the conventional configuration in which the operation amount is stepless. can do.

  That is, in the presser foot lifting device 1 of the present embodiment, the height position of the presser foot 4 is set for each operation amount category, and therefore the operating means 13 for keeping the height position of the presser foot 4 constant. Is easy (when the operation amount is within the range of one section, the height position of the presser foot 4 is constant). On the other hand, in the case of a configuration in which the conventional operation amount is stepless, the height position of the presser foot is raised and lowered in conjunction with the increase and decrease of the operation amount, so that the height position of the presser foot is kept constant. Is difficult.

  Furthermore, according to the presser lifting device 1 of the present embodiment, since the operation amount of the operation means 13 is divided into multiple stages, the presser intended by the operator is compared with the conventional configuration in which the operation amount is stepless. The raising operation can be executed quickly.

  That is, in the presser foot lifting device 1 of the present embodiment, it is possible to perform drive control of the actuator 9 that moves the presser foot 4 for each operation amount category. On the other hand, in the case of a configuration in which the conventional operation amount is stepless, drive control of the electric actuator that moves the presser foot in conjunction with increase / decrease of the operation amount is performed. It is necessary to sequentially perform operations necessary for drive control.

  The cloth cutting device for a sewing machine according to the present invention can be used in a configuration in which a presser lifting lever that moves the presser bar up and down manually by an operator is used as an operation means.

  The present invention is not limited to the above-described embodiments, and various modifications can be made as necessary.

The schematic diagram which simplifies and shows the principal part of embodiment of the presser foot raising apparatus of the sewing machine which concerns on this invention Explanatory drawing which shows an example of the multistage division | segmentation of the operation amount in embodiment of the sewing machine presser lifting apparatus of FIG. The schematic diagram which shows the state which located the cloth presser of FIG. 1 in the 1st raising position. The same figure as FIG. 3 which shows the state which located the cloth presser of FIG. 1 in the 2nd raising position. The same figure as FIG. 3 which shows the state which has located the cloth presser of FIG. 1 in the maximum raising position The flowchart explaining operation | movement of embodiment of the presser foot raising apparatus of the sewing machine which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Presser lifting device 2 Presser bar 3 Arm 4 Work clamp 5 Bed 6 Presser bar holding 7 Presser lifter 8 Link mechanism 9 Actuator 10 Driving force transmission means 11 Control means 12 Fabric thickness detection means 13 Operation means 14 Operation amount detection means 15 CPU
16 Memory 17 Fixed value storage unit 18 First raising position setting unit 19 Operation position determination unit 20 Presser lifting operation control unit T Thickness of sewing object t (of the sewing object cloth) P1 First section P2 Second section P3 Third section P4 4th division α fixed value

Claims (1)

In a presser lifting device for a sewing machine in which a presser foot attached to a lower end portion of a presser bar supported by an arm so as to be movable up and down is pressed against and separated from the bed in order to press a cloth to be sewn against the bed.
Operation means for performing an operation input for contacting and separating the presser foot;
An actuator driven by an operation input of the operation means;
Driving force transmission means for moving the presser bar up and down by the driving force of the actuator;
An operation amount detection means for detecting an operation amount of the operation means;
Cloth thickness detecting means for detecting the thickness of the sewing object cloth to be subjected to sewing;
Control means for controlling the operation of each part of the sewing machine,
The control means includes
A fixed value storage unit that stores in advance a fixed value used to move the cloth presser to the first raised position for positioning the cloth to be sewn for sewing on the bed;
In response to the detection signal of the thickness of the cloth to be sewn sent from the cloth thickness detecting means, the fixed value stored in the fixed value storage unit is added to the thickness of the cloth to be sewn, for sewing. A first lift position setting unit that calculates and stores a height position from the bed that is a first lift position of the presser foot corresponding to a sewing target cloth to be provided;
Based on the operation amount of the operation means sent out from the operation amount detection means, the operation position of the operation means is at least an initial position at which the cloth presser presses the surface of the sewing object cloth placed on the bed. An operation position determination unit that performs multi-stage determination so as to include the first ascending position;
When at least the operation position determination unit determines that the operation position of the operation means is the first lift position, the height position of the presser foot is calculated and stored by the first lift position setting hand. A presser-lifting device for a sewing machine, comprising: a press-up operation control unit that drives and controls the actuator so as to be positioned.

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