Sewing machine

Abstract

To improve operability of a feed lever in a sewing machine which adjusts a feed amount of an object to be sewn with an actuator.SOLUTION: A sewing machine includes: a feed adjustment mechanism 50 for changing and adjusting a feed amount of an object to be sewn by an actuator 57; a setting input part 95 for setting the feed amount; and a control device 90 for controlling the operation amount of the actuator of the feed adjustment mechanism according to the set value of the feed amount from the setting input part. The sewing machine also includes: a feed lever 70 for changing and adjusting the feed amount by a rotation operation from an initial position P0; a first return spring 74 for returning the feed lever to the initial position; and a detection part 73 for detecting the operation amount from the initial position of the feed lever. In the case where the operation amount from the initial position of the feed lever detected by the detection part is within a first operation amount Q1, the control device does not vary the operation amount of the actuator, and in the case where it exceeds the first operation amount, the control device varies the operation amount of the actuator according to the operation amount.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a sewing machine capable of adjusting the feeding amount of a workpiece to be sewn by an actuator.

Background Art

[0002] Conventional sewing machines that sandwich and feed a workpiece to be sewn with a presser foot and feed dogs can adjust the sewing pitch (feeding amount per stitch) of the workpiece to be sewn by an actuator such as a motor, and can feed the workpiece to be sewn at an arbitrary sewing pitch set from an operation panel (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, during sewing, there is a demand to temporarily change the sewing pitch according to the situation. For example, as shown in FIG. 9, when the target position E at the end of sewing approaches, if sewing is performed at the current sewing pitch, it is expected that the final stitch will exceed the target position E. In this case, the operator of the sewing machine changes the set value so that the sewing pitch becomes smaller only for the final stitch, and makes adjustments so that sewing is completed at the target position E as shown in FIG. 10. In addition, there are also demands such as performing backstitching at the start or end of sewing, and performing so-called condenser sewing in which sewing is performed at a very small sewing pitch at the end of sewing. In order to easily perform such temporary adjustments of the sewing pitch, conventional sewing machines have been provided with a feed lever for temporarily adjusting the sewing pitch and the feed direction by manual operation.

[0005] This feed lever is mounted on a sewing machine that adjusts the sewing pitch with a manual adjustment dial, which is older than a sewing machine (hereinafter referred to as a motor-adjustable sewing machine) that adjusts the sewing pitch with a motor. Due to its convenience, it is desired to mount the feed lever on a motor-adjustable sewing machine as well. In the case of a mechanically adjustable sewing machine, it can be incorporated so that the input torque of the feed lever is transmitted to the feed adjustment mechanism. However, in the case of a motor-adjustable sewing machine, since a motor is connected to the feed adjustment mechanism, if the input torque of the feed lever is input as it is, it will interfere with the motor. Therefore, it is difficult to directly incorporate the feed lever into the feed adjustment mechanism.

[0006] Therefore, in order to mount a feed lever on a motor-adjustable sewing machine, it is necessary to detect the amount of rotational operation by the feed lever with a sensor and control the motor so that the sewing pitch of the workpiece to be sewn is changed and adjusted according to the detected amount of rotational operation.

[0007] FIG. 11 is a front view showing the operating state of the feed lever. The feed lever is at the initial position P0 when not operated, as shown by the two-dot chain line in the upper figure, and is pushed downward from the initial position P0 to adjust the sewing pitch. In the case of a feed lever incorporated in a mechanically adjustable sewing machine, play is provided between the members that transmit torque from the feed lever. The period from the initial position P0 shown by the two-dot chain line in the upper figure to the first position P1 shown by the two-dot chain line in the lower figure is the free-running period due to the play. And the actual input section from the first position P1 to the second position P2 shown by the solid line is where the members that transmit torque from the feed lever come into contact and input torque to the feed adjustment mechanism, enabling the sewing pitch to be changed and adjusted. Note that the feed lever can be operated with a light force during the free-running period. However, in the actual input section, since the members of the feed adjustment mechanism are moved by manual force, it is necessary to operate the feed lever with more force than in the free-running period.

[0008] On the other hand, when a feed lever is mounted on a motor-adjustable sewing machine, there is no mechanical play, so there is no free play section of the feed lever, and when the feed lever is pushed down from the initial position P0, the variation in the sewing pitch occurs immediately. When fine operations such as adjustment of the sewing pitch are required, since the free play due to play like that of the feed lever of a conventional mechanically adjustable sewing machine has a predictive effect before the variation in the sewing pitch occurs, it may be easy for the operator to perform the operation and it may be possible to perform the adjustment work well. In particular, when trying to change the sewing pitch operation at a good timing, the effect becomes more prominent. Also, the feed lever of a mechanically adjustable sewing machine has a repulsive force for inputting the feed lever that switches between the free play section and the actual input section. Since it is possible to grasp by touch that the feed lever enters the actual input section, it was possible to perform the adjustment work even better.

[0009] An object of the present invention is to improve the operability of a feed lever in a sewing machine capable of adjusting the feed amount of a workpiece to be sewn by an actuator.

Means for Solving the Problems

[0010] In the sewing machine of the present invention, a feed adjustment mechanism for changing and adjusting the feed amount of the workpiece to be sewn by an actuator, a setting input unit for setting the feed amount of the workpiece to be sewn, a control device for controlling the operation amount of the actuator of the feed adjustment mechanism according to the set value of the feed amount of the workpiece to be sewn from the setting input unit, in a sewing machine comprising a feed lever for changing and adjusting the feed amount of the workpiece to be sewn by a rotation operation from the initial position, a first return spring for returning the feed lever to the initial position, and a detection unit for detecting the input operation amount of the feed lever from the initial position, the control device When the input operation amount from the initial position of the feed lever detected by the detection unit is within the first operation amount, the operation amount of the actuator is not changed. When the input operation amount from the initial position of the feed lever detected by the detection unit exceeds the first operation amount, the operation amount of the actuator is changed according to the input operation amount.

Effect of the Invention

[0011] With the above configuration, the present invention can improve the operability of the feed lever.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0013] [Schematic Configuration of Embodiment] Hereinafter, the sewing machine 100 provided with the feed adjustment mechanism which is an embodiment of the present invention will be described in detail. FIG. 1 is a perspective view showing the whole sewing machine 100, and FIG. 2 is a perspective view showing the main configuration inside the bed portion of the sewing machine 100.

[0014] As shown in FIGS. 1 and 2, the sewing machine 100 includes a needle vertical movement mechanism (not shown) that moves the needle bar 19 holding the sewing needle 18 up and down by the rotation of the upper shaft, a sewing machine motor 16 (see FIG. 7) that is a driving source for the rotation of the upper shaft, a bobbin 12 that winds the upper thread around the lower thread, a feed mechanism 30 that feeds the workpiece to be sewn on the needle plate 11 in synchronization with the vertical movement of the sewing needle, a belt mechanism 20 that transmits the rotational force from the upper shaft to the vertical feed shaft 33 of the feed mechanism 30, a sewing machine frame 10 that supports each of the above components, and a control device 90 (see FIG. 7) that controls each of the above components. The sewing machine 100 is a so-called straight-stitch sewing machine and includes components such as a balance mechanism, thread tensioner, and presser that are provided in a general straight-stitch sewing machine. However, since these are well-known, the description thereof is omitted.

[0015] The sewing machine frame 10 includes a bed portion 13 located at the lower part of the whole sewing machine, a vertical cylinder portion 14 erected upward at one end in the longitudinal direction of the bed portion 13, and an arm portion 15 (not shown) extending from the upper end portion of the vertical cylinder portion 14 in the same direction as the bed portion 13. In the following description, the horizontal direction parallel to the longitudinal direction of the bed portion 13 is defined as the Y-axis direction, the horizontal direction perpendicular to the Y-axis direction is defined as the X-axis direction, and the direction perpendicular to the X-axis and Y-axis directions is defined as the Z-axis direction. The X-axis direction coincides with the feeding direction of the workpiece to be sewn.

[0016] [Needle Vertical Movement Mechanism and Belt Mechanism] The needle vertical movement mechanism is disposed inside the arm portion 15, and includes an upper shaft that is rotationally driven by a sewing machine motor 16 and disposed along the Y-axis direction, a needle bar that holds the sewing needle at its lower end, and a crank mechanism that converts the rotational force of the upper shaft into a reciprocating driving force of vertical movement and transmits it to the needle bar (both are not shown in the figure). The upper shaft is connected to the needle bar 19 via a crank mechanism at one end in the Y-axis direction, and the other end in the Y-axis direction is connected to a hand-operated pulley 23 outside the sewing machine frame 10. In the following description, the side of the needle bar 19 in the direction along the upper shaft (Y-axis direction) is referred to as the "left side", and the side of the pulley 23 is referred to as the "right side". The belt mechanism 20 includes a driving pulley (not shown) fixedly installed on the upper shaft, a driven pulley 21 fixedly installed on the vertical feed shaft 33 of the feed mechanism 30, and a timing belt 22 wound around the driving pulley and the driven pulley 21. And by the belt mechanism 20, the vertical feed shaft 33 rotates at the same speed as the upper shaft for one full rotation. Note that instead of the belt mechanism 20, a gear transmission mechanism consisting of a vertical shaft along the Z-axis direction and bevel gears may be used to transmit the rotational force from the upper shaft to the vertical feed shaft 33.

[0017] [Feed Mechanism] As shown in FIG. 2, the feed mechanism 30 includes feed teeth 31 that protrude from and retract into the opening of the needle plate 11 to feed the workpiece to be sewn in a predetermined direction, a feed base 32 that holds the feed teeth 31, a horizontal feed mechanism 40 that obtains power from the sewing machine motor 16 and transmits a reciprocating motion in the X-axis direction (horizontal direction) to the feed base 32, and a vertical feed mechanism 60 that imparts a reciprocating motion in the vertical direction to the feed base 32.

[0018] [Horizontal Feed Mechanism] The horizontal feed mechanism 40 includes a feed adjustment mechanism 50 that adjusts the stroke of the reciprocating motion in the X-axis direction with respect to the feed base 32, a connecting rod 41 that extracts a reciprocating motion along the X-axis direction from the vertical feed shaft 33, a horizontal feed shaft 42 that is given a reciprocating rotation via the feed adjustment mechanism 50 from the connecting rod 41, and a horizontal feed arm 43 that converts the reciprocating rotation driving force of the horizontal feed shaft 42 into a reciprocating driving force in the feed direction (X-axis direction) and transmits it to the feed base 32.

[0019] The connecting rod 41 rotatably holds an eccentric cam 44 whose one end is fixedly mounted on the vertical feed shaft 33, and the other end is connected to the feed adjustment mechanism 50. Such a connecting rod 41 is arranged such that its longitudinal direction generally follows the X-axis direction. When the vertical feed shaft 33 is driven for a full rotation, the other end of the connecting rod 41 reciprocates along its longitudinal direction with a stroke that is twice the eccentricity of the eccentric cam 44. The reciprocating motion of such a connecting rod 41 is transmitted as a reciprocating rotational force to the horizontal feed shaft 42 via the feed adjustment mechanism 50.

[0020] [Feed adjustment mechanism] FIG. 3 is a perspective view of the feed adjustment mechanism 50. As shown in FIGS. 2 and 3, the feed adjustment mechanism 50 includes a swing arm 51 that is fixedly mounted on the horizontal feed shaft 42 and extends radially outward about the horizontal feed shaft 42, a pair of first link bodies 53 that connect the other end of the connecting rod 41 and the swing arm 51, a pair of second link bodies 54 that guide the reciprocating motion direction of the other end of the connecting rod 41 in any direction along the X-Z plane, a feed adjustment body 55 that determines the guiding direction by the second link bodies 54, a support shaft 52 that rotates integrally with the feed adjustment body 55, an input arm 56 that is fixedly mounted on the support shaft 52 and extends radially outward about the support shaft 52, a feed adjustment motor 57 as an actuator that rotates the feed adjustment body 55 to adjust the reciprocating motion amount in the X-axis direction (horizontal direction) transmitted from the vertical feed shaft 33 to the feed table 32, an output arm 58 fixedly attached to the output shaft of the feed adjustment motor 57, and a transmission link 59 that connects the input arm 56 and the output arm 58. Note that the positions of the horizontal feed shaft 42 and the vertical feed shaft 33 may be arranged by swapping them.

[0021] One end of the first link body 53 is connected to the other end of the connecting rod 41, the other end is connected to the swing end of the swing arm 51, and both of these ends are connected so as to be rotatable about the Y-axis. The second link body 54 has one end connected to the other end of the connecting rod 41 together with one end of the first link body 53, and the other end connected to the feed adjusting body 55. Both ends of the second link body 54 are connected so as to be rotatable about the Y-axis.

[0022] The feed adjusting body 55 has a support shaft 52 fixedly connected along the Y-axis direction, and the support shaft 52 and the feed adjusting body 55 are supported so as to be rotatable about the Y-axis within the sewing machine frame. With respect to the connection positions of the pair of second link bodies 54 on the feed adjusting body 55, the support shaft 52 is eccentric by a distance equal to the axial distance between the rotation axes of both ends of the second link body 54 and is connected to the feed adjusting body 55.

[0023] In the feed adjusting mechanism 50, when the feed adjusting body 55 is rotated so that the longitudinal directions of the first link body 53 and the second link body 54 coincide, that is, the link bodies 53, 54 are exactly overlapped when viewed from the Y-axis direction, the reciprocating motion at the other end of the connecting rod 41 is not transmitted to the swing arm 51. That is, in this state, the first link body 53 rotates about the other end side connected to the swing arm 51 as the rotation center, and the one end side connected to the connecting rod 41 reciprocally rotates, and no rotation motion is transmitted to the swing arm 51 side. Therefore, since the reciprocating rotation motion is not transmitted to the horizontal feed shaft 42 either, the reciprocating stroke of the feed table 32 in the X-axis direction becomes 0, that is, the sewing pitch becomes 0. In this way, the rotation angle of the feed adjusting body 55 in which the link bodies 53, 54 overlap is defined as the "neutral angle of the feed adjusting body 55".

[0024] When the feed adjusting body 55 is rotated from the neutral angle to one side, a reciprocating swing motion is imparted to the swing arm 51 side according to the amount of the rotation angle, and thereby the sewing pitch in the forward feed direction can be increased. Also, when the feed adjustment body 55 is rotated in the reverse direction from the neutral angle, a reciprocating swinging motion can also be imparted to the swing arm 51 side according to the amount of the rotation angle. In this case, however, the phase is inverted and transmitted, whereby the sewing pitch in the reverse feed direction can be increased.

[0025] The feed adjustment motor 57 is disposed at one end side in the Y-axis direction within the bed portion with its output shaft oriented in the Y-axis direction. One end of the aforementioned output arm 58 is fixedly attached to the output shaft of the feed adjustment motor 57 with its longitudinal direction generally oriented in the X-axis direction. Therefore, when the feed adjustment motor 57 is driven, the other end of the output arm 58 rotates up and down. The transmission link 59 is connected to the other end of the output arm 58 so as to be rotatable about the Y-axis with its longitudinal direction generally along the Z-axis direction. Therefore, when the feed adjustment motor 57 is driven, the transmission link 59 moves up and down as a whole. The input arm 56 is fixedly attached to the support shaft 52 and extends generally along the X-axis direction from the support shaft 52, and the extending end thereof is connected to the upper end of the transmission link 59 so as to be rotatable about the Y-axis. Thus, when the feed adjustment motor 57 is driven, the support shaft 52 and the feed adjustment body 55 can be rotated via the output arm 58, the transmission link 59, and the input arm 56.

[0026] The horizontal feed shaft 42 is rotatably supported within the bed portion along the Y-axis direction, and is disposed on the downstream side (leftward in FIG. 1) in the feeding direction of the workpiece to be sewn with respect to the vertical feed shaft 33. A reciprocating rotational force is applied to one end on the upright portion side of the horizontal feed shaft 42 from the vertical feed shaft 33 via the aforementioned feed adjustment mechanism 50, and a reciprocating motion along the X-axis direction is transmitted from the other end of the horizontal feed shaft 42 to the feed table 32 via the horizontal feed arm 43.

[0027] The base end portion of the horizontal feed arm 43 is fixedly connected to the end portion of the horizontal feed shaft 42 on the needle plate 11 side, and the swinging end portion thereof is connected to the feed table 32 so as to be rotatable about the Y-axis in a state generally directed upward. Therefore, the horizontal feed arm 43 can reciprocate the feed table 32 along the X-axis direction by driving the sewing machine motor 16. Further, the stroke of the reciprocating motion of the feed table 32 along the X-axis direction can be arbitrarily adjusted by controlling the feed adjustment motor 57 of the feed adjustment mechanism 50.

[0028] [Vertical feed mechanism] As shown in FIG. 1, the vertical feed mechanism 60 includes a vertical feed shaft 33 that performs the above-described full rotation, a circular eccentric cam 61 fixedly provided at an end of the vertical feed shaft 33 on the needle plate 11 side, and a connecting rod 62 that rotatably holds the eccentric cam 61 at one end.

[0029] One end of the connecting rod 62 has the eccentric cam 61 as described above, and the other end is connected to one end of the feed table 32 in the X-axis direction so as to be rotatable about the Y-axis. Further, the other end of the connecting rod 62 extends upward. Therefore, when a full rotation is imparted to the vertical feed shaft 33, the connecting rod 62 reciprocates along its vertical direction with a stroke that is twice the eccentricity of the eccentric cam 61, and a reciprocating vertical motion can be imparted to the feed table 32.

[0030] [Feed table] The feed table 32 is disposed below the needle plate 11. One end in the feeding direction (X-axis direction) of the workpiece to be sewn is connected to the connecting rod 62, and the other end is connected to the horizontal feed arm 43. Further, feed teeth 31 are fixedly provided on the upper part of the intermediate position in the longitudinal direction of the feed table 32. Thereby, a reciprocating driving force in the vertical direction is imparted to one end of the feed table 32, and a reciprocating driving force in the feeding direction is imparted to the other end with the same period. By synthesizing these reciprocating driving forces, a circular motion is performed along a locus of an ellipse in the X-Z plane. Along with this feed table 32, the feed teeth 31 also perform a circular motion of an ellipse, and when moving in the upper region of the locus of the circular motion of the ellipse, the tip of the feed teeth 31 protrudes upward from the opening of the needle plate 11, enabling the workpiece to be sewn to be fed.

[0031] [Feed Lever] When a target value of the stitch pitch as the feed amount of the workpiece to be sewn is set from the setting input unit 95 described later, the control device 90 controls the shaft angle of the output shaft of the feed adjustment motor 57 so as to be the target value of the stitch pitch. Therefore, the sewing machine 100 can feed the workpiece to be sewn at the target value of the stitch pitch. On the other hand, regardless of the target value of the stitch pitch from the setting input unit 95, when a manual rotation operation is applied to the feed lever 70, the stitch pitch can be adjusted to increase or decrease.

[0032] As shown in FIG. 1, the feed lever 70 is provided on the surface of one side in the X-axis direction (the upstream side in the feed direction of the workpiece to be sewn, hereinafter referred to as the "front side") of the vertical body portion 14 of the sewing machine frame 10. The surface of the vertical body portion 14 where the feed lever 70 is provided is a surface facing the operator who performs sewing on the sewing machine 100.

[0033] FIGS. 4 to 6 are side views of the periphery of the feed lever 70 as viewed from the right side. Around the feed lever 70, there are provided a support shaft 71 that rotatably supports the feed lever 70, a bracket 72 that is rotatably supported by the support shaft 71 separately from the feed lever 70, a lever detection unit 73 composed of a sensor that detects the input operation amount of the feed lever 70, a first return spring 74 that returns the feed lever 70 to the initial position P0 (see FIG. 4), and a second return spring 75 that applies an elastic force to the feed lever 70 toward the initial position P0 when the input operation amount from the initial position P0 of the feed lever 70 exceeds a first operation amount Q1 (see FIG. 5) described later.

[0034] The support shaft 71 is composed of, for example, a stud bolt and is fastened and fixed to the outer wall of the vertical body portion 14 in a state along the Y-axis direction. The feed lever 70 has an input portion 702 that extends forward from a central portion 701 through which a support shaft 71 is inserted, with the extended end bent toward the left and extending along the Y-axis direction with a certain length, a detected portion 703 that extends from the central portion 701 toward the non-operator side (downstream side in the feeding direction of the workpiece to be sewn, hereinafter referred to as the "rear side"), and a pressure-receiving portion 704 that abuts against the bracket 72 with the first operation amount Q1 described above.

[0035] The position shown in FIG. 4 is the initial position P0 of the feed lever 70, and a stopper (not shown) is provided so that the feed lever 70 cannot rotate in the clockwise direction in FIG. 4 from the initial position P0. That is, the feed lever 70 has a structure that can only be operated in the direction of pushing downward from the initial position P0. The first return spring 74 is a tension spring made of a coil spring, and imparts an upward tension to the feed lever 70 that can pull the input portion 702 back to the initial position P0.

[0036] The detected portion 703 is a portion where position detection is performed on the lever detection portion 73 in order to detect the operation amount of the feed lever 70. The detected portion 703 extends obliquely upward from the central portion 701 toward the rear side, and the extended end thereof is bent downward. The lever detection portion 73 detects the height of the lower end portion of the downward extension portion of the detected portion 703. For example, the lever detection portion 73 has a light source and a light-receiving element of detection light with a specific wavelength, such as infrared rays, arranged to face each other so as to sandwich the lower end portion of the detected portion 703 from both sides in the Y-axis direction. The light-receiving element has innumerable light-receiving portions arranged in a matrix, and by specifying the light-receiving portion with the lowest position among the light-receiving portions where the light-receiving amount of the detection light is reduced due to the shielding of the detected portion 703, the height of the lower end portion of the detected portion 703 can be detected. Since there is an integral correlation between the height of the lower end portion of the detected portion 703 and the input operation amount (rotation angle) from the initial position P0 of the feed lever 70, table data recording these correlations is prepared, and the control device 90 can specify the input operation amount from the initial position P0 of the feed lever 70 by referring to this. Note that the height of the lower end of the detected detected part 703 itself may be regarded as the input operation amount from the initial position of the feed lever 70, and processing and control associated with the input operation of the feed lever 70 may be performed.

[0037] Note that the lever detection unit 73 is not limited to the light source and the light receiving element, and any sensor capable of detecting the input operation amount from the initial position P0 of the feed lever 70 can be used. For example, a sensor capable of detecting the rotation amount such as an encoder, a rotary potentiometer, or a resolver may be provided in parallel with the feed lever 70, or a sensor for detecting the position of the lower end of the detected part 703 by magnetism may be provided in the vicinity of the detected part 703.

[0038] The pressure receiving part 704 extends downward from the central part 701 and in a direction inclined somewhat toward the front side. As described above, a bracket 72 that is rotatable about the support shaft 71 is arranged on the left side of the feed lever 70. A round bar-shaped protrusion 721 protruding toward the right along the Y-axis direction is provided at the lower part of the bracket 72. The bracket 72 is maintained in a constant orientation around the support shaft 71 by a second return spring 75 made of a torsion coil spring.

[0039] Note that the support shaft 71 is inserted into the coil part of the second return spring 75 and is rotatably supported. One end of the second return spring 75 is bent in a hook shape and inserted into a locking hole 722 provided in the bracket 72, and the other end is fixed by a stopper 141 provided on the vertical body part 14 so as not to rotate around the support shaft 71.

[0040] When the input part 702 of the feed lever 70 is pushed downward from the initial position P0 and rotated, as shown in FIG. 5, the pressure receiving part 704 abuts against the outer periphery of the protrusion 721 of the bracket 72. The input operation amount (rotation angle amount) from the initial position P0 of the feed lever 70 at the time of this abutment is defined as the first operation amount Q1. In contrast, the bracket 72 is held by the second return spring 75. Therefore, as shown in FIG. 6, when the feed lever 70 further rotates beyond the first operation amount Q1, in addition to the return force toward the initial position P0 by the first return spring 74, the pressure receiving portion 704 newly receives the return force toward the initial position P0 by the second return spring 75. That is, when the operator applies a rotational operation to the feed lever 70 that exceeds the first operation amount Q1, the operator can feel a clear increase in the return force when exceeding the first operation amount Q1.

[0041] When the feed lever 70 rotates from the position in FIG. 5 to the position in FIG. 6, on the way, the lower end portion of the detected portion 703 comes out upward from the upper end portion of the detection range of the lever detection portion 73. At this time, it is detected that the lower end portion of the detected portion 703 at the moment of coming out of the detection range is located at the upper limit value of the detection range of the lever detection portion 73. The input operation amount from the initial position P0 of the feed lever 70 at this time is defined as the third operation amount (the second operation amount will be described separately later). When the control device 90 detects the third operation amount as the input operation amount from the initial position P0 of the feed lever 70, and then when the lower end portion of the detected portion 703 comes out of the upper end portion of the detection range of the lever detection portion 73 and is no longer detected, it is regarded that the input of the third operation amount is maintained, and the processing and control associated with the input operation of the feed lever 70 are performed. That is, while the input operation exceeding the third operation amount is being performed from the feed lever 70, the control device 90 recognizes that the input of the detectable third operation amount is continuously being performed.

[0042] [Sewing machine control system] The control system of the sewing machine 100 is shown in the block diagram of FIG. 7. As shown in FIG. 7, the control device 90 of the sewing machine 100 includes a ROM (Read Only Memory) 92 in which a program for controlling the operation of each component is stored, a RAM (Random Access Memory) 93 serving as a work area for arithmetic processing, a rewritable non-volatile data memory 94 as storage means for storing various setting data, etc., and a CPU 91 (Central Processing Unit) for executing the program in the ROM 92. And the sewing machine motor 16 and the feed adjustment motor 57 are connected to this control device 90 via the respective motor drive circuits 16a, 57a. In addition, an encoder 161 for detecting the rotational speed of the sewing machine motor 16 is provided together therewith, and this encoder 161 is also connected to the control device 90 via the motor drive circuit 16a. Further, a lever detection unit 73 for detecting the input operation amount of the above-described feed lever 70 is connected to the control device 90 via an interface 73a.

[0043] Furthermore, a setting input unit 95 for inputting the execution and setting of various operation controls for the sewing machine 100 is connected to the control device 90 via an interface 95a. The setting input unit 95 is composed of, for example, a liquid crystal display (LCD: Liquid Crystal Display) with a touch panel and functions as a display unit and an input unit. The display unit displays various setting screens, the operating state of the sewing machine, etc. according to the display control signal input from the CPU 91. The input unit is composed of a touch sensor for detecting a touch operation applied to the display surface of the display unit, and can receive various inputs in cooperation with the input screen displayed on the display unit. For example, the setting input unit 95 can perform setting of the sewing pitch, setting of the first to third operation amounts Q1 to Q3 of the feed lever 70 described later, etc.

[0044] [Settings of various operation amounts] Here, the setting of the first to third operation amounts Q1 to Q3 of the feed lever 70 will be described. As described above, the first operation amount Q1 of the feed lever 70 is the input operation amount (rotation angle amount) from the initial position P0 when the feed lever 70 is rotated and the pressure receiving portion 704 abuts against the protrusion 721 of the bracket 72. The first operation amount Q1 can be obtained from the design values of the feed lever 70 and its surroundings, but individual differences may occur from the design values due to machining errors or assembly errors of parts. Therefore, when actually operating the feed lever 70, the output of the lever detection unit 73 when the pressure receiving portion 704 first abuts against the protrusion 721 of the bracket 72 or the rotation angle from the initial position P0 of the feed lever 70 obtained from the output can be set as the first operation amount Q1.

[0045] When the CPU 91 of the control device 90 detects an operation reaching the first operation amount Q1 for the feed lever 70 by the lever detection unit 73, it executes control of the feed adjustment motor 57 so as to increase or decrease the set value of the stitch pitch according to the input operation amount exceeding the first operation amount Q1.

[0046] Specifically, as shown in FIG. 6, when the detection value of the lever detection unit 73 exceeds the first operation amount Q1, the CPU 91 executes control of the feed adjustment motor 57 so as to gradually decrease the set value of the stitch pitch from the initial set value (for example, the stitch pitch set by the setting input unit 95) according to the increase in the operation amount (rotation in the reverse direction of the feed adjustment body 55 described above).

[0047] Furthermore, when the detection value of the lever detection unit 73 reaches a second operation amount Q2 larger than the first operation amount Q1, the CPU 91 executes control of the feed adjustment motor 57 so as to set the stitch pitch to 0 (set the feed adjustment body 55 to the neutral angle). That is, the CPU 91 gradually decreases the set value of the stitch pitch from the initial set value to 0 at a certain rate during the process of operating the feed lever 70 from the first operation amount Q1 to the second operation amount Q2.

[0048] When the detection value of the lever detection unit 73 exceeds the second operation amount Q2, the CPU 91 switches the set value of the sewing pitch from 0 to reverse feed in response to the increase in the operation amount, and controls the feed adjustment motor 57 so as to gradually increase the sewing pitch of the reverse feed (rotation in the reverse direction after the neutral angle of the feed adjustment body 55 described above).

[0049] Furthermore, when the detection value of the lever detection unit 73 reaches the third operation amount Q3 that is larger than the second operation amount Q2, the CPU 91 controls the feed adjustment motor 57 so that the sewing pitch becomes the maximum value of the preset sewing pitch of the reverse feed. That is, the CPU 91 gradually increases the set value of the sewing pitch at a rate that becomes the maximum value of the sewing pitch of the reverse feed from 0 to the reverse feed in the process of operating the feed lever 70 until reaching the third operation amount Q3 from the second operation amount Q2. Note that, as described above, the third operation amount Q3 is the operation amount immediately before the lower end of the detected portion 703 of the feed lever 70 exits the detection range of the lever detection unit 73. Therefore, when the lower end of the detected portion 703 exits the detection range of the lever detection unit 73 and is not detected, the CPU 91 maintains the maximum value of the sewing pitch of the reverse feed again until the lower end of the detected portion 703 is detected.

[0050] Note that the maximum value of the sewing pitch of the reverse feed may also be settable from the setting input unit 95. Further, the CPU 91 may be configured to automatically recognize the maximum value of the sewing pitch of the reverse feed as the sewing pitch of the reverse feed having the same magnitude as the set value of the sewing pitch of the forward feed set from the setting input unit 95. Also, the first to third operation amounts Q1 to Q3 can also be set to arbitrary operation amounts from the setting input unit 95. However, they are restricted so that Q1 < Q2 < Q3.

[0051] [Technical Effects of Embodiment of Invention] When the input operation amount from the initial position P0 of the feed lever 70 detected by the lever detection unit 73 is within the first operation amount Q1, the CPU 91 of the control device 90 of the sewing machine 100 does not change the operation amount of the feed adjustment motor 57. When the input operation amount from the initial position P0 of the feed lever 70 detected by the lever detection unit 73 exceeds the first operation amount Q1, control is performed to change the operation amount of the feed adjustment motor 57 according to the input operation amount. Therefore, the feed lever 70 is pushed in from the initial position P0, which is the standby position when not operated. Until the first operation amount Q1 is reached, it becomes an idle running section where the sewing pitch maintains the set value, and the same effect as mechanical play can be obtained. A predictive effect before the variation of the sewing pitch occurs can be obtained by this idle running section, and for the operator, it becomes possible to perform the adjustment work well. In particular, when trying to change the sewing pitch at a good timing, it becomes easier to take the timing to change the feed pitch, and it becomes possible to improve the operability. Also, for an operator accustomed to using the feed lever of a mechanically adjustable sewing machine, an operation feeling similar to that of the feed lever of a mechanically adjustable sewing machine can be obtained, so it becomes possible to perform good operation.

[0052] The sewing machine 100 also includes a second return spring 75 that applies an elastic force toward the initial position P0 side to the feed lever 70 together with the first return spring 74 when the input operation amount from the initial position P0 of the feed lever 70 exceeds the first operation amount Q1. Therefore, when the feed lever 70 exceeds the first operation amount Q1, the operator can feel a sudden increase in the repulsive force from the feed lever 70, and it becomes possible to recognize the start of the actual input section where the variation of the sewing pitch begins from the change in the operation feeling.

[0053] In addition, when the detection value of the input operation amount from the initial position P0 of the feed lever 70 by the lever detection unit 73 exceeds the first operation amount Q1, the CPU 91 of the control device 90 controls the feed adjustment motor 57 so as to reduce the feed amount of the workpiece to be sewn as the input operation amount increases. Therefore, it becomes possible to perform control suitable for the request to reduce the stitch pitch at any timing of sewing.

[0054] In addition, when the detection value of the input operation amount from the initial position P0 of the feed lever 70 by the lever detection unit 73 reaches the second operation amount Q2 which is larger than the first operation amount Q1, the feed amount of the workpiece to be sewn is reduced to 0. When the second operation amount Q2 is exceeded, the feed adjustment motor 57 is controlled so that the feed amount of the workpiece to be sewn increases in reverse feed as the rotation angle amount increases. Therefore, it becomes possible to perform control suitable for the request to minimize the stitch pitch at any timing of sewing or to perform reverse feed.

[0055] In addition, when the detection value of the input operation amount from the initial position P0 of the feed lever 70 by the lever detection unit 73 becomes equal to or greater than the third operation amount Q3 which is larger than the second operation amount Q2, the feed adjustment motor 57 is controlled so as to maintain the default maximum value of the reverse feed of the feed amount of the workpiece to be sewn. Therefore, when it is desired to perform reverse feed at the maximum stitch pitch at any timing of sewing, it is only necessary to push the feed lever 70 in as far as possible, and there is no need to adjust the pushing amount of the feed lever so as to obtain the target stitch pitch, and it becomes possible to easily switch the stitch pitch.

[0056] In addition, since the first operation amount Q1 can be arbitrarily set by the input from the setting input unit 95, it is possible to set the free run section of the feed lever 70 to an appropriate width that each operator feels. In addition, by making it possible to arbitrarily set the first operation amount Q1, it becomes possible to more accurately adjust the position where the return force by the second return spring 75 of the feed lever 70 starts to be generated and the position where the change adjustment of the stitch pitch by the feed adjustment motor 57 starts to coincide.

[0057] In addition, since the second operation amount Q2 can be arbitrarily set by the input from the setting input unit 95, it is possible to set the position where the sewing pitch is set to 0 and the position where the feed lever 70 switches to reverse feed at appropriate positions that each operator feels.

[0058] In addition, since the third operation amount Q3 can be arbitrarily set by the input from the setting input unit 95, it is possible to set the position where the sewing pitch switches to the maximum sewing pitch in reverse feed at appropriate positions that each operator feels at the feed lever 70.

[0059] [Another example of the peripheral structure of the feed lever] Another example of the peripheral structure of the feed lever 70 will be described. FIG. 8 is a side view of another example of the peripheral structure of the feed lever 70 as viewed from the right side. In the configuration of FIGS. 4 to 6 described above, the configuration in which the restoring force of the second return spring 75 is applied to the feed lever 70 via the bracket 72 is illustrated. However, when the operation amount of the feed lever 70 exceeds the first operation amount Q1, any other configuration may be used as long as the restoring force clearly fluctuates.

[0060] In the example of FIG. 8, the bracket 72 disposed on the left side of the feed lever 70 is omitted, and a configuration is shown in which the pressure receiving portion 704 of the feed lever 70 directly presses the second return spring 75. In this case, in the example of FIG. 4, one end portion that was connected to the bracket 72 in the second return spring 75 is inserted into the locking hole 142 provided in the standing cylinder portion 14, and the second return spring 75 is locked so as not to rotate around the support shaft 71. On the other hand, the other end portion of the second return spring 75 is disposed so as to be able to contact the pressure receiving portion 704, and is set to contact the pressure receiving portion 704 when an operation is applied to the feed lever 70 from the initial position P0 until the first operation amount Q1 is reached.

[0061] Incidentally, when the operation amount of the feed lever 70 exceeds the first operation amount Q1, the other end of the second return spring 75 rotates around the support shaft 71 together with the pressure receiving portion 704. Therefore, the stopper 141 having a structure that restricts both sides in the circumferential direction centered on the support shaft 71 shown in the example of FIG. 4 is not used. The stopper 143 at the other end of the second return spring 75 is arranged to abut against the pressure receiving portion 704 at the other end of the second return spring 75 when the operation amount of the feed lever 70 is the first operation amount Q1 on the side surface of the vertical cylinder portion 14, and is configured to abut against the other end of the second return spring 75 from the upstream side in the operation direction of the feed lever 70.

[0062] Thus, even in the case of the configuration of FIG. 8, it functions in the same manner as in the case of the configuration of FIG. 4. Note that, for the feed lever 70 in FIG. 8, illustration of the detected portion 703 and the lever detection portion 73 is omitted.

[0063] [Another Example of Processing of Feed Lever by Control Device] Referring to FIG. 6, another example of the processing of the feed lever 70 by the control device 90 will be described. In the above-described processing examples described with reference to FIGS. 4 to 6, when the operation amount from the initial position P0 of the feed lever 70 exceeds the first operation amount Q1, thereafter, the control of the feed adjustment motor 57 is performed such that the sewing pitch varies in the process of gradually decreasing the sewing pitch, reaching a sewing pitch of 0, and gradually increasing the reverse sewing pitch. However, the processing of the feed lever 70 is not limited to this, and the following processing may be performed. That is, when the operation amount from the initial position P0 of the feed lever 70 becomes equal to or greater than the fourth operation amount Q4 which is greater than the first operation amount Q1, the CPU 91 of the control device 90 may control the feed adjustment motor 57 so that the sewing pitch of the workpiece to be sewn maintains a predetermined target value. In this case, it is not necessary to set the second operation amount Q2 and the third operation amount Q3.

[0064] The fourth operation amount may be greater than the first operation amount Q1 and equal to or less than the third operation amount Q3 described above. When the detected operation amount is between the first operation amount Q1 and the fourth operation amount Q4, the sewing pitch of the workpiece to be sewn may or may not vary. When the fourth operation amount Q4 is reached, the feed adjustment motor 57 is controlled so that the sewing pitch becomes a predetermined target value. Also, when the operation amount exceeds the fourth operation amount Q4, the predetermined target value is maintained.

[0065] This example of the process is suitable for sewing with two types of sewing pitches, such as when sewing is performed at the standard sewing pitch set by the setting input unit 95 during normal sewing and when it is desired to change to another predetermined sewing pitch in a specific case. In this case, sewing is performed at the standard sewing pitch, and it is not possible to respond to situations where the sewing pitch is increased or decreased during sewing. However, if the sizes of the two types of sewing pitches required are known in advance, when switching the sewing pitch, the feed lever 70 may be pushed in as far as possible, eliminating the need for an operation to find an appropriate position while pushing in the feed lever 70, and enabling the operation to be performed simply and quickly.

[0066] Regarding the above-mentioned first operation amount Q1, fourth operation amount Q4, and the predetermined target value of the sewing pitch, it is preferably possible to arbitrarily set them from the setting input unit 95. However, it is restricted so that Q1 < Q4.

[0067] [Others] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. For example, in the embodiments, components integrally formed by a single member may be replaced with components divided into a plurality of members and connected or fixed to each other. Also, components configured by connecting a plurality of members may be replaced with components integrally formed by a single member. In addition, the details shown in the embodiments can be appropriately changed without departing from the spirit of the invention.

[0068] For example, by setting the reciprocating operation amount by the horizontal feeding mechanism of the feeding mechanism to be constant and making the reciprocating operation amount by the vertical feeding mechanism changeable by controlling a motor as an actuator, it is also possible to control the feeding amount of the workpiece to be sewn for each stitch. And also in the case of a sewing machine equipped with such a feeding mechanism, it is possible to apply the configuration of the above-described feeding lever 70 and the operation control for the operation to the above-described feeding lever 70.

Explanation of Signs

[0069] 10 Sewing machine frame 11 Needle plate 12 Bobbin 13 Bed part 14 Upright cylinder part 15 Arm part 16 Sewing machine motor 18 Sewing needle 19 Needle bar 20 Belt mechanism 30 Feeding mechanism 31 Feeding teeth 40 Horizontal feeding mechanism 50 Feeding adjustment mechanism 55 Feeding adjustment body 57 Feeding adjustment motor (actuator) 60 Vertical feeding mechanism 70 Feeding lever 71 Support shaft 72 Bracket 73 Lever detection part (detection part) 74 First return spring 75 Second return spring 90 Control device 91 CPU 95 Setting input part 100 Sewing machine 701 Central part 702 Input part 703 Detected part 704 Pressure receiving part P0 Initial position Q1 First operation amount Q2 Second operation amount Q3 Third operation amount Q4 Fourth operation amount

Claims

1. A feed adjustment mechanism for changing and adjusting the feed amount of a workpiece by an actuator, A setting input unit for setting the feed amount of the workpiece, A control device for controlling the operation amount of the actuator of the feed adjustment mechanism according to the set value of the feed amount of the workpiece from the setting input unit, In a sewing machine provided with, A feed lever for changing and adjusting the feed amount of the workpiece by a rotation operation from an initial position, A first return spring for returning the feed lever to the initial position, And a detection unit for detecting the input operation amount of the feed lever from the initial position, The control device, When the input operation amount of the feed lever detected by the detection unit from the initial position is within a first operation amount, the operation amount of the actuator is not changed, When the input operation amount of the feed lever detected by the detection unit from the initial position exceeds the first operation amount, the operation amount of the actuator is changed according to the input operation amount. A sewing machine characterized by that.

2. When the input operation amount of the feed lever from the initial position exceeds the first operation amount, a second return spring for applying an elastic force to the feed lever toward the initial position together with the first return spring is provided. The sewing machine according to claim 1, characterized in that.

3. When the detection value of the input operation amount of the feed lever from the initial position by the detection unit exceeds the first operation amount, the control device reduces the feed amount of the workpiece as the input operation amount increases. The sewing machine according to claim 1 or claim 2, characterized in that the actuator is controlled.

4. When the detection value of the input operation amount of the feed lever from the initial position by the detection unit reaches a second operation amount larger than the first operation amount, the control device reduces the feed amount of the workpiece to 0, and When exceeding the second operation amount, the actuator is controlled so that the feed amount of the workpiece increases in reverse feed as the input operation amount increases. The sewing machine according to claim 3, characterized in that.

5. When the detection value of the input operation amount of the feed lever from the initial position by the detection unit becomes equal to or greater than a third operation amount larger than the second operation amount, the control device sets the feed amount of the workpiece to a reverse feed. The sewing machine according to claim 4, characterized in that the actuator is controlled so as to maintain a predetermined maximum value.

6. The sewing machine according to claim 3, wherein the first operation amount can be arbitrarily set by an input from the setting input unit.

7. The sewing machine according to claim 4, wherein the second operation amount can be arbitrarily set by an input from the setting input unit.

8. The sewing machine according to claim 5, wherein the third operation amount can be arbitrarily set by an input from the setting input unit.

9. When the detection value of the input operation amount from the initial position of the feed lever by the detection unit is equal to or greater than a fourth operation amount that is greater than the first operation amount, the control device controls the actuator so as to maintain the feed amount of the workpiece to be sewn at a predetermined target value. The sewing machine according to claim 1 or claim 2.

10. The sewing machine according to claim 9, wherein the fourth operation amount can be arbitrarily set by an input from the setting input unit.

11. The sewing machine according to claim 9, wherein the predetermined target value can be arbitrarily set by an input from the setting input unit.

Images