Cloth presser of sewing machine

Abstract

To achieve a cloth presser of a sewing machine which enables sewing in which stitch balancing thread tension is stabilized.SOLUTION: A cloth presser 100 of a sewing machine includes: a first cloth presser part 12 which moves vertically being interlocked with the vertical movement of a needle bar 3; and a second cloth presser 22 which is installed at fixed height on a needle plate 1. With this configuration, at the timing when the needle bar 3 is lowered and a sewing needle 2 pierces a cloth, the cloth placed on the needle plate 1 can be pressed by the first cloth presser part 12, and during the time when the needle bar 3 is raised, the sewing needle 2 is pulled out of the cloth, and a balance finishes pulling up a needle thread, the cloth being raised by the sewing needle 2 and the needle thread can be restricted by the second cloth presser part 22. Therefore, sewing in which stitch balancing thread tension is stabilized can be achieved.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a presser foot for a sewing machine. [Background technology]

[0002] BACKGROUND ART Conventionally, in sewing machines for performing embroidery stitching or free motion stitching, a presser foot for a sewing machine is known in which a presser foot portion moves up and down in accordance with the up and down movement of the needle bar of the sewing machine (see, for example, Patent Document 1). The presser foot of this sewing machine is provided with an operating arm, and the needle clamp part of the needle bar comes into contact with the operating arm from below, pushing up the operating arm, so that the presser foot moves up and down in conjunction with the up and down movement of the needle bar. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-161431 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of a fabric presser foot that moves up and down in accordance with the up and down movement of the needle bar, as in Patent Document 1, the fabric presser part does not press down on the fabric from the time the needle holder part of the needle bar pushes up the fabric presser foot until the thread take-up has finished pulling up the upper thread, so there is a problem in that the fabric is lifted up by the upper thread pulled up by the sewing needle or the thread take-up, causing it to flutter, and the thread tension can become unstable.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide a sewing machine presser foot that enables sewing with stable thread tension. [Means for solving the problem]

[0006] In order to solve the above problems, the invention described in claim 1 is as follows: In a sewing machine having a needle plate and a needle bar up-and-down movement mechanism for moving a needle bar holding a sewing needle up and down, a presser foot of the sewing machine is attached to a presser bar provided near the needle bar via a presser foot support member, a first presser foot and a second presser foot supported by the presser foot support member; the first presser foot includes a first presser portion supported so as to be movable up and down in conjunction with the up and down movement of the needle bar; The second presser foot is characterized by having a second presser portion supported so as to be movable up and down, and an adjustment portion for adjusting the height position of the second presser portion relative to the needle plate.

[0007] The invention described in claim 2 is the sewing machine presser foot described in claim 1, The second presser foot is characterized in that the second presser foot portion is adjusted by the adjustment portion to a height at which it does not come into contact with the fabric placed on the needle plate.

[0008] The invention described in claim 3 is the sewing machine presser foot described in claim 2, The first presser section is characterized by being movable up and down between a height at which it is in contact with the needle plate at a position lower than the second presser section, and a height at which it is in contact with the needle plate at a position higher than the second presser section.

[0009] The invention described in claim 4 is the cloth presser foot of the sewing machine described in any one of claims 1 to 3, the first presser foot includes a spring member that biases the first presser portion toward the needle plate, and a contact arm that contacts the needle bar when the needle bar rises and transmits the upward movement to the first presser portion, The second presser foot is characterized by including a spring member that biases the second presser foot portion toward the needle plate.

[0010] The invention described in claim 5 is the sewing machine presser foot described in claim 4, The presser foot support member has a first through hole and a second through hole extending vertically therethrough, the first presser foot includes a first shaft portion inserted into the first through-hole, The first shaft portion has the contact arm portion at its upper end and the first presser portion at its lower end, the second presser foot includes a second shaft portion inserted into the second through-hole, The second shaft portion is characterized in that the adjustment portion is provided on the upper end side and the first presser portion is provided on the lower end side.

[0011] The invention described in claim 6 is the sewing machine presser foot described in claim 5, a first guide shaft that is parallel to the first shaft portion is provided in the first presser portion; A second guide shaft is provided in the second presser portion in parallel with the second shaft portion, The presser foot support member is formed with a first guide hole and a second guide hole that penetrate in the vertical direction, The first guide shaft is inserted through the first guide hole, and the second guide shaft is inserted through the second guide hole. [Effects of the Invention]

[0012] According to the present invention, a sewing machine presser foot that enables sewing with stable thread tension is provided. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view of a sewing machine to which a presser foot of the sewing machine according to an embodiment of the present invention is attached. [Figure 2] FIG. 2 is a perspective view showing a presser foot of the sewing machine attached to the sewing machine. [Figure 3] FIG. 2 is a front view showing the presser foot of the sewing machine attached to the sewing machine. [Figure 4] 1A is a perspective view showing a presser foot of a sewing machine according to an embodiment of the present invention, and FIG. 1B is a perspective view showing a part of the presser foot in a see-through manner. [Figure 5] 1A is a side view showing a presser foot of a sewing machine according to an embodiment of the present invention, and FIG. 1B is a side view showing a part of the presser foot in a perspective view. [Figure 6] 2 is a side view showing a part of the cloth presser foot of the sewing machine of the present embodiment in perspective; FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail. A sewing machine presser foot is attached to the sewing machine and functions to hold down the material being sewn during sewing.

[0015] The sewing machine presser foot 100 of this embodiment is used by being attached to the presser bar 4 of the sewing machine M, for example, as shown in FIGS. This sewing machine M is equipped with a needle plate 1, a needle bar 3 which has a needle holder 3a for holding a sewing needle 2 and moves up and down, a presser bar 4 provided near the needle bar 3, and the like. Needle holder 3 a of needle bar 3 has a screw-type knob that is loosened or tightened when attaching sewing needle 2 to the lower end of needle bar 3 , and protrudes approximately perpendicular to needle bar 3 . In addition, if a predetermined presser foot is already installed on the presser bar 4 of the sewing machine M, the presser foot 100 of the sewing machine of this embodiment will be attached to the presser bar 4 in place of that presser foot.

[0016] The sewing machine M also includes a needle bar up-down movement mechanism that moves the needle bar 3 holding the sewing needle 2 up and down, a shuttle mechanism that captures the upper thread passed through the sewing needle 2 and entangles it with the bobbin thread, and a take-up mechanism that pulls up the upper thread to form a knot, all of which are stored in the sewing machine frame. The sewing machine frame consists of a sewing machine bed section located below the sewing machine body, a standing body section standing upright from one end of the sewing machine bed section, and a sewing machine arm section extending from the standing body section in the same direction as the sewing machine bed section. The needle plate 1 is provided in the bed of the sewing machine, and the needle bar 3 and the presser bar 4 are provided in the arm of the sewing machine. The configuration and operation of each mechanism of this sewing machine M are the same as those of conventionally known mechanisms, and therefore will not be described in detail here. The sewing machine M is a sewing machine capable of performing so-called free motion sewing, in which the operator manually moves the fabric as the sewing object and sews while positioning the fabric relative to the needle drop position.

[0017] The presser foot 100 of the sewing machine of this embodiment includes a first presser foot 10, a second presser foot 20, and a presser foot support member 30 that supports the first presser foot 10 and the second presser foot 20, as shown in, for example, Figures 2, 4(a)(b), and 5(a)(b).

[0018] The presser foot support member 30 has an attachment portion 31 for attaching the presser foot 100 of the sewing machine to the presser bar 4, and a support body 32 for supporting the first presser foot 10 and the second presser foot 20.

[0019] The mounting portion 31 is provided with a notched groove portion 31a. With the presser foot 4 attached to the inside of this mounting portion 31, the fixing screw 30a is threaded into the fixing hole (not shown) of the presser foot 4 through the groove portion 31a, and the mounting portion 31 is sandwiched between the fixing screw 30a and the presser foot bar 4, thereby fixing the presser foot support member 30 to the presser foot bar 4, and the presser foot 100 of the sewing machine can be attached to the presser foot bar 4. Furthermore, the structure and mounting method of the mounting portion 31 are the same as those of conventionally known ones, and the presser foot 100 of the sewing machine of this embodiment ensures compatibility with conventional presser feet.

[0020] A pair of through holes, a first through hole 32a and a second through hole 32b, which penetrate in the vertical direction, are formed in the support body 32. A shaft of a cloth presser foot, which will be described later, is inserted into these through holes. A pair of guide holes, a first guide hole 32c and a second guide hole 32d, which penetrate vertically, are formed in the support body 32. A guide shaft of a cloth presser foot, which will be described later, is inserted into these guide holes. These four holes (first through hole 32a, second through hole 32b, first guide hole 32c, second guide hole 32d) are formed parallel to one another.

[0021] The first presser foot 10 has a first shaft portion 11 inserted through the first through-hole 32a of the presser foot support member 30, a first presser portion 12 provided at the lower end side of the first shaft portion 11 and positioned above the needle plate 1, and a contact arm portion 13 provided at the upper end side of the first shaft portion 11 and with which the needle holding portion 3a comes into contact and is lifted when the lowered needle bar 3 rises. Further, a first guide shaft 14 is provided in the first presser foot portion 12 so as to stand parallel to the first shaft portion 11, and this first guide shaft 14 is inserted into a first guide hole 32c of the presser foot support member 30.

[0022] The first presser foot 12 has a bent tip end that is positioned approximately parallel to the needle plate 1, and the tip end is provided with a needle hole 12a through which the sewing needle 2 is loosely inserted. The tip of the first presser foot 12 is a presser foot that presses down the fabric placed on the needle plate 1.

[0023] The first presser foot 10 has a coil spring 11a, which is a spring member that urges the first presser foot 12 toward the needle plate 1, and the first presser foot 12 is elastically supported so that it can move up and down. The coil spring 11a is inserted into the first shaft portion 11 and arranged between the first cloth pressing portion 12 and the support portion main body 32, with the lower end of the coil spring 11a abutting against the first cloth pressing portion 12 and the upper end abutting against the support portion main body 32.

[0024] The contact arm 13 is fixed to the upper end of the first shaft 11 so that a part of the contact arm 13 protrudes to the side surface of the support body 32. Needle holder 3a, which rises together with needle bar 3, comes into contact with contact arm 13, and is pushed up together with needle holder 3a. In other words, when needle bar 3 rises, needle holder 3a comes into contact with contact arm 13, and the upward movement is transmitted to first presser foot 12. When the contact arm 13 is pushed up by the needle holder 3a, the first presser foot 12 rises together with the first shaft 11. At this time, the coil spring 11a contracts between the first presser foot 12 and the support body 32. Furthermore, when needle bar 3 (needle holder 3a) descends, first shaft 11 and first presser foot 12 also descend integrally with contact arm 13 due to the biasing force of coil spring 11a as it expands. In this way, the first presser foot 10 is moved up and down in conjunction with the up and down movement of the needle bar 3, so that the height of the first presser foot portion 12 is adjusted up and down. In particular, since the first shaft portion 11 and the first guide shaft 14 of the first cloth presser 10 are inserted into the first through hole 32a and the first guide hole 32c of the support portion main body 32, respectively, the posture of the first cloth presser portion 12 is less likely to be disturbed, and the up and down movement of the first cloth presser portion 12 is stable.

[0025] The second presser foot 20 has a second shaft portion 21 inserted into the second through-hole 32b of the presser foot support member 30, a second presser portion 22 provided on the lower end side of the second shaft portion 21 and positioned above the needle plate 1, and an adjustment portion 23 provided on the upper end side of the second shaft portion 21 for adjusting the position of the second shaft portion 21 in the vertical direction. Further, the second presser foot 22 has a second guide shaft 24 extending parallel to the second shaft 21, and the second guide shaft 24 is inserted into a second guide hole 32d of the presser foot support member 30.

[0026] The second presser foot 22 is bent so that its tip is disposed substantially parallel to the needle plate 1 . The tip of the second presser portion 22 is provided with a notch 22a through which the tip of the first presser portion 12 passes up and down. Moreover, on both sides of the notch 22a at the tip of the second presser foot 22, there are provided curved portions 22b, which are the edges of the tip that curve upward.

[0027] The second presser foot 20 has a coil spring 21a, which is a spring member that urges the second presser foot 22 toward the needle plate 1, and the second presser foot 22 is elastically supported so as to be movable up and down. The coil spring 21a is inserted into the second shaft portion 21 and arranged between the second cloth pressing portion 22 and the support portion main body 32, with the lower end of the coil spring 21a abutting against the second cloth pressing portion 22 and the upper end abutting against the support portion main body 32.

[0028] The adjustment portion 23 is, for example, a female-threaded member that is screwed into a male-threaded portion formed on the upper end side of the second shaft portion 21, as shown in FIG. When the adjustment part 23 is turned clockwise so as to tighten it toward the support part main body 32, the second shaft part 21 is threaded relatively upward, and the second cloth pressing part 22 rises so as to move away from the needle plate 1. When the adjustment part 23 is turned counterclockwise, the second shaft part 21 is threaded relatively downward, and the second cloth pressing part 22 descends so as to approach the needle plate 1. The second presser foot 22 can be set at a height according to the position of the second shaft 21 adjusted by the adjustment unit 23. In particular, since the second shaft portion 21 and the second guide shaft 24 of the second cloth presser 20 are inserted into the second through hole 32b and the second guide hole 32d of the support portion main body 32, respectively, the posture of the second cloth presser portion 22 is less likely to be disturbed, and the vertical movement of the second cloth presser portion 22 is stabilized.

[0029] Next, the function of the presser foot 100 of the sewing machine of this embodiment will be described.

[0030] When the sewing machine presser foot 100 is attached to the presser bar 4 of the sewing machine M and the needle holder 3a of the needle bar 3 is not in contact with the contact arm 13 of the first presser foot 10, the tip of the first presser part 12 of the first presser foot 10 is located lower than the tip of the second presser part 22 of the second presser foot 20 and abuts against the needle plate 1. The first cloth presser foot 10 has a coil spring 11a that biases the first cloth presser portion 12 toward the needle plate 1, and the first cloth presser portion 12 is elastically supported so that it can move up and down, so that the tip portion of the first cloth presser portion 12 abuts against the needle plate 1 in a manner that it butts against the needle plate 1. The tip of the first presser foot 12 that contacts the needle plate 1 presses down on the fabric placed on the needle plate 1. On the other hand, the height of the second presser foot 22 of the second presser foot 20 is adjusted by the adjusting part 23 so that the tip of the second presser foot 22 is located at a position away from the needle plate 1 . The tip of the second presser foot 22, which is located away from the needle plate 1, is positioned at a height that does not contact the fabric placed on the needle plate 1. In this way, the needle clamping portion 3a of the needle bar 3 is not in contact with the contact arm portion 13 of the first cloth presser foot 10, and at the time when the needle bar 3 descends and the sewing needle 2 pierces the fabric, the fabric placed on the needle plate 1 is pressed down by the tip portion of the first cloth presser foot 12.

[0031] Furthermore, when the needle bar 3 is raised and the needle clamping portion 3a of the needle bar 3 presses up the contact arm portion 13 of the first cloth presser foot 10, the first cloth presser portion 12 of the first cloth presser foot 10 rises and the tip portion of the first cloth presser portion 12 is positioned higher than the tip portion of the second cloth presser portion 22 (see FIG. 5(a) ; the first cloth presser portion 12 is shown by a chain line). While the needle clamping portion 3a of the needle bar 3 is pushing up the contact arm portion 13 of the first cloth presser foot 10 in this manner, the tip portion of the first cloth presser foot 12 does not press down on the fabric placed on the needle plate 1. On the other hand, the tip portion of the second cloth pressing portion 22 of the second cloth pressing foot 20 is slightly separated from the needle plate 1 but is positioned relatively close to the fabric on the needle plate 1. Therefore, while the tip portion of the first cloth pressing portion 12 is positioned above the tip portion of the second cloth pressing portion 22, the tip portion of the second cloth pressing portion 22 can prevent the fabric from being lifted upward due to friction of the upper thread pulled up by the thread take-up lever.

[0032] In other words, when sewing with a sewing machine M equipped with the sewing machine presser foot 100 of this embodiment, at the time when the needle bar 3 descends and the sewing needle 2 pierces the fabric, the fabric placed on the needle plate 1 can be pressed down by the tip of the first presser foot 12, and while the needle bar 3 rises and the needle holder 3a of the needle bar 3 presses up the first presser foot 10, the tip of the second presser foot 22 can prevent the fabric from being lifted by the upper thread. When the needle bar 3 is raised and the sewing needle 2 is removed from the fabric, the fabric placed on the needle plate 1 is not pressed down by the first fabric pressing section 12 or the second fabric pressing section 22, so the fabric on the needle plate 1 can be moved smoothly, allowing for suitable free motion sewing.

[0033] The tip of the second cloth pressing part 22, which is located away from the needle plate 1, is at a fixed height above the needle plate 1. Therefore, if there is a thick step in the fabric, the tip of the second cloth pressing part 22 may come into contact with the step. However, the second cloth pressing part 20 has a coil spring 21a that urges the second cloth pressing part 22 toward the needle plate 1, and the second cloth pressing part 22 is elastically supported so that it can move up and down. Therefore, when the tip of the second cloth pressing part 22 comes into contact with the step in the fabric, the second cloth pressing part 22 can move upward to retract. In addition, the tip portion of the second cloth pressing portion 22 is provided with a curved portion 22b, where the edge of the tip portion is curved upward, so that when the tip portion of the second cloth pressing portion 22 comes into contact with a stepped portion of the fabric, the second cloth pressing portion 22 can suitably retreat so as to climb over the stepped portion.

[0034] As described above, the cloth presser foot 100 of the sewing machine of this embodiment has two types of cloth presser sections: the first cloth presser section 12 that moves up and down in conjunction with the up and down movement of the needle bar 3, and the second cloth presser section 22 that is installed at a fixed height above the needle plate 1.This means that the thread tension is not disturbed from the time the sewing needle 2 comes out of the fabric until the thread take-up has finished pulling up the upper thread, allowing for efficient free motion sewing.

[0035] The shape of the mounting portion 31 of the presser foot 100 of the sewing machine of this embodiment is the same as that of the mounting portion of a conventional presser foot. Furthermore, the presser foot 100 has the first presser foot 10 and the second presser foot 20 integrally configured via the support body 32, so that the two types of presser foot parts can be easily attached to a conventional sewing machine while maintaining compatibility with the presser foot of the conventional sewing machine.

[0036] In the above embodiment, the needle holder 3a for holding the sewing needle 2 contacts and pushes up the contact arm 13 of the first presser foot 10, thereby raising the first presser foot 12. However, a separate member that contacts the contact arm 13 may be provided on the needle bar 3 to raise the first presser foot 12.

[0037] In the above embodiment, an example has been given of the case where the sewing machine presser foot 100 is attached to a sewing machine M that performs free motion sewing, in which the fabric is positioned relative to the needle drop position while sewing, but the present invention can also be applied to a free motion sewing machine in which the sewing machine moves relative to the fabric held on a predetermined loading surface.

[0038] In addition, in the above embodiment, the sewing machine presser foot 100 is attached to a sewing machine M capable of performing free motion sewing and used, but the present invention is not limited to this, and the sewing machine presser foot 100 may also be attached to a sewing machine that performs embroidery sewing and used.

[0039] Furthermore, it goes without saying that other specific detailed structures and the like can be modified as appropriate. [Explanation of symbols]

[0040] 1 Throat plate 2 sewing needles 3 needle bar 3a Needle holder 4 Fabric presser bar 10 First presser foot 11 First shaft 11a Coil spring (spring member) 12 First presser foot 12a needle hole 13 Contact arm 14 First guide shaft 20 Second presser foot 21 Second shaft 21a Coil spring (spring member) 22 Second presser foot 22a Notch 22b Warped part 23 Adjustment section 24 Second guide shaft 30 Work clamp support member 30a fixing screw 31 Mounting part 31a Groove 32 Support body 32a 1st through hole 32b 2nd through hole 32c First guide hole 32d Second guide hole 100 Sewing machine presser foot M sewing machine

Claims

1. In a sewing machine having a needle plate and a needle bar up-and-down movement mechanism for moving a needle bar holding a sewing needle up and down, a presser foot of the sewing machine is attached to a presser bar provided near the needle bar via a presser foot support member, a first presser foot and a second presser foot supported by the presser foot support member; the first presser foot includes a first presser portion supported so as to be movable up and down in conjunction with the up and down movement of the needle bar; The second presser foot of a sewing machine is characterized in that it comprises a second presser portion supported so as to be movable up and down, and an adjustment portion for adjusting the height position of the second presser portion relative to the needle plate.

2. 2. The sewing machine presser foot according to claim 1, wherein the second presser portion of the second presser foot is adjusted by the adjustment portion to a height such that it does not come into contact with the fabric placed on the needle plate.

3. 3. The sewing machine presser foot according to claim 2, wherein the first presser foot moves up and down between a height at which it is in contact with the needle plate at a position lower than the second presser foot and a height at which it is in contact with the needle plate at a position higher than the second presser foot.

4. the first presser foot includes a spring member that biases the first presser portion toward the needle plate, and a contact arm that contacts the needle bar when the needle bar rises and transmits the upward movement to the first presser portion, 4. The sewing machine presser foot according to claim 1, wherein the second presser foot includes a spring member that biases the second presser foot toward the needle plate.

5. The presser foot support member has a first through hole and a second through hole extending therethrough in the vertical direction, the first presser foot includes a first shaft portion inserted into the first through-hole, The first shaft portion has the contact arm portion at an upper end thereof and the first presser portion at a lower end thereof, the second presser foot includes a second shaft portion inserted into the second through-hole, 5. The presser foot for a sewing machine according to claim 4, wherein the second shaft portion is provided with the adjustment portion at an upper end thereof and the first presser portion at a lower end thereof.

6. a first guide shaft that is parallel to the first shaft portion and that is provided upright on the first presser portion; a second guide shaft that is parallel to the second shaft portion and that is provided upright on the second presser portion; The presser foot support member is formed with a first guide hole and a second guide hole that penetrate in the vertical direction, 6. The presser foot for a sewing machine according to claim 5, wherein the first guide shaft is inserted through the first guide hole, and the second guide shaft is inserted through the second guide hole.

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