JP2015073742A - Direct drive cloth feed mechanism for sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a direct drive cloth feed mechanism for a sewing machine.SOLUTION: A direct drive cloth feed mechanism for a sewing machine includes a cloth feed structure 1, a vertical drive structure 2 and a direction adjustment structure 3. The cloth feed structure 1 includes a swing shaft rod 11 and a cloth feed dog 12. The vertical drive structure 2 includes an eccentric rod 21 connected to the cloth feed dog 12 and an eccentric cam 22 mounted on the eccentric rod 21. The direction adjustment structure 3 includes a step motor 31 and a shaft 321 which is driven by the step motor 31 to rotate and to be switched between a first position A1 and a second position A2. When the shaft 321 is directly driven by the step motor 31 to be switched to the first position A1, the cloth feed dog 12 performs a forward cloth feed stroke. When the shaft 321 is directly driven by the step motor 31 to be switched to the second position A2, the cloth feed dog 12 performs a backward cloth feed stroke.

Description

  The present invention relates to a cloth feed mechanism for a sewing machine, and more particularly to a direct drive cloth feed mechanism for a sewing machine.

  In the conventional sewing machine, it is necessary to perform forward sewing or backward sewing processing work depending on the necessity for sewing. This is the so-called “straight stitching and reverse stitching” work. Many sewing machines change the direction by associating a control structure with a single power source to achieve normal and reverse stitches. In the conventional reverse stitch transmission mechanism, the lever is moved by hand, the transmission parts are interlocked, and the rotation of the transmission shaft is used to interlock the movement of the cloth feed dog. Furthermore, the purpose of performing the sewing operation by reversing the cloth and returning the position by interlocking the jagged surface on the cloth feed dog and retreating the cloth is achieved. However, such an operation is very time consuming and needs to be held down by hand, which places a burden on the operator. As a result, the working efficiency is greatly reduced and the economic efficiency is low.

  In view of the above-described drawbacks, a structure has been developed that drives a reverse stitch transmission mechanism by causing an electromagnet to correspond to a connecting rod. This structure can achieve the effect of automating reverse stitching by controlling the connecting rod with an electromagnet. However, the conventional electromagnet is connected to a plurality of connecting rods and driven, and further, the transmission parts are controlled by the connecting rods.Thus, the cloth feed dog performs the control method of positive and reverse stitching, but this structure is complicated. In addition, the connecting rod connected between the electromagnet and the power transmission component is easy to loosen, or power transmission is likely to be inaccurate due to poor assembly. In addition, in this type of structure using the indirect drive system of the connecting rod and the electromagnet, the rotation angle of the interlocking component cannot be accurately controlled, and further, the movement of the cloth feed dog cannot be accurately controlled. The present invention has been made in view of the above-described drawbacks of the conventional cloth feed mechanism of a sewing machine.

  The problem to be solved by the present invention is to provide a direct drive cloth feed mechanism for a sewing machine that can solve the problem of insufficient transmission accuracy existing in the conventional structure.

In order to solve the above problems, the present invention provides the following direct drive cloth feed mechanism for a sewing machine.
The direct drive cloth feed mechanism of the sewing machine has a cloth feed structure, a vertical drive structure, and a direction adjustment structure.
The cloth feed structure includes a swing shaft rod, a cloth feed tooth that is movably installed on the swing shaft rod, and that receives the interlock of the swing shaft rod and performs horizontal reciprocating movement.
The vertical drive structure is connected to the cloth feed dog, is driven by a drive motor, and is installed on the eccentric rod that causes the cloth feed dog to perform vertical reciprocating movement, and the eccentric rod is interlocked. Equipped with an eccentric cam that receives and rotates,
The direction adjustment structure includes a step motor, an adjustment unit that receives the drive of the step motor,
The adjustment unit is movably connected to the step motor, and rotates by receiving the drive of the step motor, a shaft that switches between a first position and a second position, a track unit installed in the shaft, A slide block to be installed on the swing shaft rod, connected to the eccentric cam movably, one end is provided with an interlocking rod connected to the slide block,
The interlocking rod receives the interlocking of the eccentric cam, and when the shaft switches between the first position and the second position, performs the first swing stroke and the second swing stroke, interlocks the slide block, Reciprocating slide movement at
The cloth feed teeth perform a forward cloth feed stroke when the interlocking rod performs a first swing stroke, and perform a backward advance cloth feed stroke when the interlocking rod performs a second swing stroke.
The eccentric rod passes through the eccentric cam and is rotated by a drive motor, a connecting portion that is movably connected to the cloth feed dog, and is installed eccentrically at one end of the main rod. A sub-bar is provided that is connected, receives the interlocking of the main bar, and moves the cloth feed dog vertically and reciprocally.

The direct drive cloth feed mechanism of the sewing machine of the present invention has the following effects.
The direct drive cloth feed mechanism of the sewing machine of the present invention directly interlocks the shaft of the adjusting unit through a step motor, whereby the shaft rotates and is switched from the first position to the second position, and the traveling trajectory of the interlocking rod Thus, the first swing stroke and the second swing stroke are performed.
The interlocking rod changes the position where the cloth feed dog performs horizontal reciprocation due to the difference in the traveling trajectory, and further adapts the driving force of vertical reciprocation provided by the eccentric rod to move the cloth feed dog forward and backward. Two kinds of cloth feeding processes can be performed.
Therefore, it differs from the conventional sewing machine cloth feed mechanism in which the shaft cannot be controlled unless a plurality of connecting rods are connected through an electromagnet.
In the present invention, the shaft can be directly driven by the step motor, and the rotation angle of the shaft 321 can be accurately controlled.
Thereby, the precision at the time of adjustment can be expanded and the quality of sewing by a sewing machine can be improved.

It is a schematic diagram of the assembly position of one Example of this invention. It is an external appearance schematic diagram of one Example of this invention. It is a structure decomposition | disassembly schematic diagram of one Example of this invention. It is an operation | movement schematic diagram of the forward cloth feed process of one Example of this invention. It is an operation | movement schematic diagram of the reverse cloth feed process of one Example of this invention.

  The best mode for carrying out the present invention will be described in detail below with reference to the drawings.

  As shown in FIGS. 1, 2, and 3 which are a schematic view of an assembly position, an external view schematic diagram, and a structural exploded schematic view of an embodiment of the present invention, the direct drive cloth feed mechanism of the sewing machine of the present invention is disposed in the sewing machine 100. . The direct drive cloth feed mechanism of the sewing machine includes a cloth feed structure 1, a vertical drive structure 2, and a direction adjustment structure 3. The cloth feed structure 1 includes a swing shaft 11 and a cloth feed tooth 12 that is movably installed on the swing shaft 11 and receives the interlocking of the swing shaft 11. The vertical drive structure 2 is connected to the cloth feed dog 12 and driven by a drive motor (not shown). The vertical drive structure 2 is installed on the eccentric rod 21, and the eccentric cam 22 that rotates in response to the interlock of the eccentric rod 21. Is provided. The drive motor is installed above the eccentric rod 21 and is transmitted through the belt to drive the rotation of the eccentric rod 21. The direction adjustment structure 3 includes a step motor 31 and an adjustment unit 32 that receives the drive of the step motor 31. The adjustment unit 32 rotates on the shaft 321 that is movably connected to the step motor 31 and driven by the step motor 31, and the shaft 321 that switches between the first position A1 and the second position A2, and the track unit that is installed in the shaft 321. 322, a slide block 324 installed in the track portion 322, the swing shaft rod 11, and the eccentric cam 22 are movably connected, and one end is connected to the slide block 324 and swings in response to the interlocking of the eccentric cam 22. An interlocking rod 323 that interlocks 324 and performs reciprocating sliding movement within the track portion 322 is provided. In the present invention, the shaft 321 is directly driven through the step motor 31. As a result, the shaft 321 rotates at a different angle, and the cloth feed structure 1 is interlocked to perform the forward or backward cloth feed stroke.

As shown in FIG. 4 which is an operation schematic diagram of the forward cloth feed process of one embodiment of the present invention, the eccentric rod 21 passes through the eccentric cam 22 and rotates by receiving the drive of the drive motor. A connecting portion 212 movably connected to the teeth 12 and a main rod 211 are installed eccentrically at one end, connected to the connecting portion 212, and provided with a sub-rod 213 that receives the interlocking of the main rod 211. The main bar 211 normally receives the drive of the drive motor and maintains the clockwise / counterclockwise rotation. The auxiliary bar 213 installed eccentrically rotates in response to the interlocking of the main bar 211, and interlocks the cloth feed dog 12 through the connecting part 212. As a result, a vertical driving force is provided to the cloth feed teeth 12, and thus the cloth feed teeth 12 reciprocate vertically. The vertical direction and the circular center line of the longitudinal section of the main rod 211 are coaxial. When the step motor 31 drives the shaft 321 and the shaft 321 is positioned at the first position A1, the track portion 322 has a certain inclination angle, and the eccentric cam 22 rotates in conjunction with the main rod 211, and at the same time, the interlocking rod. 323 is associated, the slide block 324 is pulled and moved, and a reciprocating slide movement is performed in the track portion 322. Thus, the first swing stroke is performed.
Since the interlocking rod 323 is movably connected to the swing shaft rod 11, when the interlocking rod 323 performs the first swing stroke, the swing shaft rod 11 receives the interlock of the interlocking rod 323 and performs a reciprocating swing. In this way, the cloth feed dog 12 is interlocked to perform horizontal reciprocation. Therefore, the cloth feed dog 12 reciprocates when the interlocking rod 323 performs the first swing stroke, performs horizontal reciprocation on one side of the center line, and forms a forward cloth feed stroke corresponding to the vertical reciprocation. .

As shown in FIG. 5 which is a schematic diagram of the operation of the reverse cloth feeding process of one embodiment of the present invention, the step motor 31 is further connected to a control unit (not shown). The control unit is a switch, a control interface, or a remote control device. A control signal is transmitted to the step motor 31 through the control unit. As a result, the step motor 31 directly drives the shaft of the adjustment unit 32 to rotate the angle to the second position A2.
Moreover, the control unit can have an automatic mode and a manual mode.
When in the automatic mode, the step motor 31 drives the rotation of the shaft 321 when predetermined conditions (sewing time, number of sewing needles, etc.) are satisfied. When in the manual mode, the user can decide when to drive the step motor 31 according to the sewing situation. When the shaft 321 rotates by the step motor 31 to the second position A2, the inclination angle of the track portion 322 also changes accordingly. Thus, the reciprocating slide angle of the slide block 324 is modified, and the interlocking rod 323 is interlocked to perform the second swing stroke.
When the swing method of the interlocking rod 323 changes from the first swing stroke to the second swing stroke, the swing shaft rod 11 changes the interlocking reception and swing angle of the interlocking rod 323. In this way, the position of the horizontal reciprocation performed by the cloth feed dog 12 is modified by interlocking the cloth feed dog 12. Further, when the interlocking rod 323 performs the second swing stroke, the cloth feed dog 12 reciprocates on the opposite side of the center line and performs horizontal reciprocation. At this time, the main rod 211 is driven by the drive motor and maintains rotation in the same direction. The eccentrically installed secondary bar 213 continues to rotate in response to the interlocking of the main bar 211, and interlocks the cloth feed dog 12 through the connecting portion 212. Accordingly, a vertical driving force is provided to the cloth feed teeth 12 to cause vertical reciprocation, and the vertical reciprocation is added to the horizontal reciprocation on the side opposite to the center line, thereby forming the reverse cloth feed stroke.

  In addition, the step motor 31 of the present invention adjusts the slide block 324 through adjustment of the rotation angle of the shaft 321 to accurately control the rotation angle of the shaft 321, and performs a reciprocating slide movement process in the track portion 322. Make it. The greater the rotation angle of the shaft 321, that is, the greater the inclination of the track portion 322, the shorter the stroke in which the slide block 324 reciprocates within the track portion 322. As a result, the speed at which the cloth feed dog 12 feeds the cloth increases, and if the sewing sewing speed is the same, the stitches of the sewing machine 100 (not shown) sewn on the cloth become smaller. On the contrary, as the rotation angle of the shaft 321 becomes smaller, the stroke in which the slide block 324 reciprocates in the track portion 322 becomes longer. In this way, the speed at which the cloth feed dog 12 feeds the cloth is slow, and if the sewing sewing speed is similar, the stitches that the sewing needle of the sewing machine 100 sews on the cloth become large. Thus, according to the present invention, the stitches of the sewing machine 100 can be controlled through the step motor 31. In the conventional sewing machine, it is necessary to switch the stitches through the dial. However, as described above, the present invention can simplify the method of using the sewing machine.

  The step motor 31 of the present invention can further drive the shaft 321 to rotate it to a third position A3 located between the first position A1 and the second position A2. Specifically, the third position A3 is the starting point. When the shaft 321 is positioned at the third position A3, the locus of the movement that the eccentric cam 22 performs in conjunction with the interlocking rod 323, and the slide block 324 slides in the track portion 322, and the interlocking rod 323 is interlocked. The movement trajectories to be performed cancel each other out. Thereby, the interlocking rod 323 does not interlock the rotation of the swing shaft rod 11. Thus, the cloth feed dog 12 is in a stationary state. The step motor 31 freely controls the shaft 321 and can switch at the first position A1, the second position A2, and the third position A3, and the cloth feed dog 12 can be moved forward, backward, and stationary. Can be controlled.

In the present invention, the shaft 321 of the adjustment unit 32 is directly linked through the step motor 31. As a result, the shaft 321 rotates and is switched from the first position A1 to the second position A2, and the traveling trajectory of the interlocking rod 323 can be changed, thus performing the first swing stroke and the second swing stroke. The interlocking rod 323 modifies the position where the cloth feed dog 12 reciprocates horizontally due to the difference in the traveling trajectory, and further corresponds to the driving force of the vertical reciprocation provided by the eccentric rod 21, Two kinds of cloth feeding strokes, forward and backward, can be performed.
Therefore, this is different from a conventional sewing machine cloth feed mechanism in which a shaft cannot be controlled unless a plurality of connecting rods are connected through an electromagnet. In the present invention, the shaft 321 can be directly driven by the step motor 31, and the rotation angle of the shaft 321 can be accurately controlled. Thereby, the accuracy at the time of adjustment is expanded, and the stitches of the sewing machine 100 are directly controlled through the step motor 31, so that the quality of sewing by the sewing machine can be improved.

100 Sewing machine 1 Cloth feed structure 11 Swing shaft bar 12 Cloth feed dog 2 Vertical drive structure 21 Eccentric rod 211 Main bar 212 Connecting part 213 Sub-bar 22 Eccentric cam 3 Directional adjustment structure 31 Step motor 32 Adjustment part 321 Shaft 322 Track part 323 Interlocking Bar 324 Slide block
A1 First position
A2 Second position
A3 Third position

Claims (2)

The direct drive cloth feed mechanism of the sewing machine has a cloth feed structure, a vertical drive structure, and a direction adjustment structure.
The cloth feed structure includes a swing feed bar that is installed in a movable manner on a swing shaft bar, the swing shaft bar, and that receives the interlock of the swing shaft bar and performs horizontal reciprocation.
The vertical drive structure is connected to the cloth feed dog, is installed on the eccentric rod that receives the drive of the drive motor and causes the cloth feed dog to perform vertical reciprocating movement, and the eccentric rod is interlocked. Equipped with an eccentric cam that receives and rotates,
The direction adjustment structure includes a step motor, an adjustment unit that receives driving of the step motor,
The adjustment unit is movably connected to the step motor, rotates by receiving the drive of the step motor, switches between a first position and a second position, a track unit installed in the shaft, The slide block installed on the swing shaft, the swing shaft rod, and the eccentric cam are movably connected, one end is provided with an interlocking rod connected to the slide block, the interlocking rod is interlocked with the eccentric cam, the shaft is When switching between the first position and the second position, the first swing stroke and the second swing stroke are performed, the slide block is interlocked, and the reciprocating slide movement is performed in the track portion.
The cloth feed dog performs a forward cloth feed stroke when the interlocking rod performs a first swing stroke, and performs a backward advance cloth feed stroke when the interlocking rod performs a second swing stroke. Direct drive cloth feed mechanism.   The eccentric rod passes through the eccentric cam and is rotated by a drive motor, a connecting portion that is movably connected to the cloth feed dog, and is installed eccentrically at one end of the main rod, and the connecting portion 2. The direct drive cloth feed mechanism for a sewing machine according to claim 1, further comprising a sub bar which is connected, receives the interlock of the main bar, and vertically reciprocates the cloth feed teeth.

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