JPH067569A - Needle rod drive releasing apparatus for multi-head type sewing machine - Google Patents

Abstract

PURPOSE:To avoid impact sounds associated with vertical action of a needle rod drive member by holding the needle rod drive member of a pause sewing head at a drive releasing position where the transmission of a driving force is cut off to a needle rod over the entire area of a vertical stroke. CONSTITUTION:This apparatus is provided with a cam face 28 formed flatly with respect to the vertical way of a needle rod drive member 24 and a drive releasing mechanism 40 which allows operation of rolling the needle drive member 24 being engaged with the cam face 28 to a drive releasing position where the transmission of driving is cut off to a needle rod 30 while being made ready to lock under this operating condition. The vertical length of the cam face 28 is so set to such dimensions that the engagement with the drive releasing mechanism 40 is held over the entire area of a vertical stroke of the needle drive member 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing operation using only some of a plurality of sewing heads.
The present invention relates to a needle bar drive releasing device of a multi-head sewing machine for holding a needle bar of a rest head in a stopped state.

[0002]

2. Description of the Related Art Conventionally, in a sewing machine of this type, as shown in FIG. 7, a needle bar drive member 90 is vertically moved along a base needle bar 20 which is arranged behind and parallel to the needle bar 30. By driving, the needle bar 30 is moved up and down in conjunction with this. That is, the engagement pin 34 of the needle bar holder 32 fixed to the needle bar 30 is engaged with the pair of upper and lower engagement protrusions 92 formed on the needle bar drive member 90, thereby driving the needle bar. Power can be transmitted from the member 90 to the needle bar 30. Then, in the sewing machine head to be stopped, the plunger 96 of the solenoid is projected on the ascending / descending locus of the cam surface 94 formed on the needle bar driving member 90. The relationship between the projecting plunger 96 and the cam surface 94 is such that the needle bar drive member 90 is moved to the engagement projection 92 and the engagement pin each time the needle bar drive member 90 rises toward the top dead center. It is set so as to rotate around the axis of the base needle bar 20 to a position where the engagement with 34 is released.
Therefore, as long as the plunger 96 of the solenoid projects, the needle bar 30 is held at the top dead center by the elastic force of the spring (not shown) regardless of the vertical movement of the needle bar drive member 90.

[0003]

In the configuration shown in FIG. 7, the needle bar drive member 9 of the sewing machine head at rest is used.
Each time 0 reciprocates in the vertical direction, the cam surface 94 collides with the plunger 96 of the solenoid, which causes vibration and noise. The technical problem of the present invention is to hold the needle bar driving member of the resting sewing machine head in the drive release position where the driving force transmission to the needle bar is cut off in the entire range of the vertical stroke thereof. It is to avoid the collision noise caused by the motion.

[0004]

In order to solve the above problems, the needle bar drive releasing device for a multi-head sewing machine according to the present invention is constructed as follows. That is, the needle bar drive member is moved up and down to move the needle bar up and down, and the needle bar drive member is rotated to its drive release position so that the drive force transmission from the needle bar drive member to the needle bar is interrupted. In a needle bar drive releasing device of a multi-head sewing machine having a structure, a cam surface formed flat with respect to the needle bar driving member in the up-down direction and the drive release of the needle bar driving member by engaging the cam surface. A drive releasing mechanism that is capable of rotating to a position and lockable in the operating state, and the vertical length of the cam surface is used to release the drive in the entire vertical stroke of the needle bar drive member. The size is set so that the engagement with the mechanism is maintained.

[0005]

According to this structure, by activating and locking the drive release mechanism, the drive release mechanism engages with the cam surface of the needle bar drive member to rotate the needle bar drive member to the drive release position. To move. The engagement between the cam surface and the drive release mechanism is maintained in the entire vertical stroke of the needle bar drive member, thereby avoiding a collision sound or the like associated with the vertical movement of the needle bar drive member in the sewing machine head during rest. It

[0006]

EXAMPLE An example of the present invention will be described below with reference to FIGS. FIG. 4 shows the inside of one sewing machine head in a front view, and FIGS. 5 and 6 show left side views of the sewing machine head. Sewing machine arm 12 shown in these figures
The rear part of the machine is attached to a sewing machine frame (not shown), and one base needle bar 20
Is provided. A drive base 22 and a needle bar drive member 24 are mounted on the shaft of the base needle bar 20 so as to move up and down while maintaining an integral relationship with each other. However, the needle bar drive member 24 is different from the drive base 22 in the base needle bar 20.
It is rotatable about its axis and is normally held in the rotating position shown in FIGS. 4 and 5 by the force of a spring (not shown).
A pair of upper and lower engaging protrusions 26 are formed on the front surface of the needle bar driving member 24, and an engaging pin 34 protruding from a needle bar holder 32 of a needle bar 30 is engaged between them. There is. A plurality of needle bars 30 are provided in a needle bar case (not shown) assembled to the front surface of the sewing machine arm 12 so as to be slidable in the left-right direction in FIG. Only the engagement pin 34 of one needle bar 30 selected by the slide control of the needle bar case engages between the engaging protrusions 26 of the needle bar drive member 24.

The sewing machine main shaft 14, which is arranged so as to penetrate the respective sewing machine arms 12 of each sewing machine head, is rotationally driven in one direction by one drive source. Then, on the axis of the sewing machine main shaft 14, the needle bar drive cam 16 is provided inside the sewing machine arm 12.
Also, the jump cam 17 is fixed. The rotation of the needle bar drive cam 16 is converted into a vertical reciprocating motion by the drive link mechanism 18 and transmitted to the drive base 22. Therefore, the drive base 22 and the needle bar drive member 24 are vertically driven based on the rotation of the sewing machine main shaft 14, and the vertical movement of the needle bar drive member 24 transmits the vertical motion to the needle bar 30. The rotation of the jump cam 17 serves as a drive source for giving a jump operation to a jump mechanism 70 described later.

Next, from the needle bar drive member 24 to the needle bar 30.
The drive release mechanism 40 for cutting off the transmission of the driving force to the drive unit will be described. As shown in FIGS. 4 to 6, a base plate 42 of the drive release mechanism 40 is attached to one side surface of the sewing machine arm 12. This base plate 4
A central boss portion 46 of a release lever 44 is rotatably supported inside the sewing machine arm 12 in FIG. The release lever 44 is urged in a direction to be received by a stopper 52 provided on the base plate 42 by a force of a torsion spring 54 attached to the outer periphery of the central boss portion 46. A pin 48 is connected to one end of the release lever 44. One end of this pin 48 projects toward the base plate 42 side, and the other end has a roller 50 rotatably provided. The other end of the release lever 44 is a tip boss 56. On the other hand, the needle bar driving member 24 has a cam surface 28 formed flat in the vertical direction. The roller 50 of the release lever 44 can contact (engage) with the cam surface 28, and the length of the cam surface 28 in the vertical direction is the same in the entire vertical stroke of the needle bar drive member 24. The size is set so that the contact with the roller 50 is maintained.

FIG. 1 is a perspective view of the drive release mechanism 40 together with a jump mechanism 70 which will be described later, and FIGS.
A side view of is shown. As is clear from these drawings, the release lever 4 is attached to the base plate 42.
An operation shaft 62 is supported at a position adjacent to the pin 48 of No. 4 so as to rotate about its axis and move in the axial direction within a slight range. An operating knob 60 is integrally attached to the operating shaft 62 outside the sewing machine arm 12, and an operating arm 64 is integrally formed at the end of the operating shaft 62 located inside the sewing machine arm 12. . Therefore, by rotating the operation knob 60, the operation arm 64 rotates around the axis of the operation shaft 62 and pushes the pin 48 of the release lever 44 to the right in FIGS. 1 to 3. . As a result, the release lever 44 is rotated around the axis of the central boss portion 46 against the elastic force of the torsion spring 54. This state is shown by, for example, a virtual line in FIG. 1, and at this time, the operation knob 6
The lock pin 66 of 0 engages with the lock hole 68 of the base plate 42 by the force of a spring (not shown) (see the state of the phantom line in FIG. 4).

Next, the jump mechanism 70 will be described. A shaft 73 is supported by the tip boss 56 of the release lever 44 so as to rotate around its axis, and one end of the shaft 73 is used for jumping. The base end of the first lever 72 and the base end of the second jump lever 78 are integrally connected to the other end. A cam follower 74 is provided at the tip of the first jump lever 72, and the cam follower 74 is held in contact with the outer circumference of the jump cam 17 by the force of the torsion spring 76 acting on the first lever 72. ing. Further, the solenoid 8 is provided on the base plate 42 coaxially with the central boss portion 46, which is the rotation axis of the release lever 44.
0 is attached. When the solenoid 80 is energized, the end of the plunger 84 projects from the end surface of the central boss 46 in the state shown in FIG. The tip of the second jump lever 78 is positioned so as to interfere with the end of the protruding plunger 84. As the member that rotatably supports the central boss portion 46 of the release lever 44, specifically, the stator 82 of the solenoid 80 assembled to the base plate 42 is used.

With respect to the sewing machine head which is suspended in the above structure, the operation knob 60 of the drive releasing mechanism 40 is rotated to a position where the lock pin engages with the lock hole 68. As a result, as described above, the operating arm 64 rotates, for example, to the state of FIG. 3 and pushes the pin 48 of the release lever 44, and the release lever 44 is held at the rotation position of FIG. As a result, the cam surface 28 of the needle bar drive member 24 is pushed by the roller 50 of the release lever 44, and the needle bar drive member 24 rotates about the axis of the base needle bar 20 to cause the engagement protrusion. The piece 26 is held in the drive release position where it is disengaged from the engagement pin 34 of the needle bar 30. That is, in this state, the transmission of the driving force from the needle bar drive member 24 to the needle bar 30 is cut off, and the sewing machine head is in a rest state. The roller 50 and the cam surface 28 are held in contact with (engaged with) each other in the entire vertical stroke of the needle bar drive member 24, so that a collision sound due to the vertical movement of the needle bar drive member 24 is generated. Avoided.

In addition to the suspension of the sewing machine head, there is a jump control for interrupting the transmission of the driving force from the needle bar drive member 24 to the needle bar 30 only when a jump signal is input during embroidery sewing or the like. To explain this jump control, the first jump lever 72 and the second jump lever 78 in the jump mechanism 70 repeat the reciprocating rotation with the shaft 73 as a rotation fulcrum as the jump cam 17 rotates. ing. When the jump signal is input in this state, the solenoid 80 is energized by this signal. As a result, as described above, the end portion of the plunger 84 projects from the end surface of the central boss portion 46 of the release lever 44. In this state, the tip portion of the second lever 78 interferes with the end portion of the plunger 84, and the first lever 72 and the second lever 78 move the release lever 4
4 and the central boss portion 46 are rotated around the axis. Therefore, the release lever 44 is reciprocally rotated by the rotation of the jump cam 17, and the needle bar drive member 2 is rotated.
4 is rotated to the drive release position as shown in FIG. 6 when it approaches the top dead center. As a result, jump control in embroidery sewing or the like is realized.

[0013]

As described above, according to the present invention, the needle bar drive member of the resting sewing machine head can be held in the drive release position where the drive force transmission to the needle bar is cut off in the entire vertical stroke thereof.
As a result, collision noise and the like that accompany the vertical movement of the needle bar drive member are avoided, and vibration and noise caused by this are prevented.

[Brief description of drawings]

FIG. 1 is a perspective view of a needle bar drive releasing device.

FIG. 2 is a side view of a needle bar drive releasing device.

FIG. 3 is a side view showing a drive release state of the needle bar drive release device.

FIG. 4 is a front view showing the inside of one sewing machine head.

FIG. 5 is a left side view of the sewing machine head.

FIG. 6 is a left side view of the sewing machine head during a jump.

FIG. 7 is an explanatory diagram showing an outline of a conventional needle bar drive releasing device.

[Explanation of symbols]

 24 needle bar drive member 30 needle bar 40 drive release mechanism

Claims (1)

[Claims] 1. The needle bar drive member is moved up and down to move the needle bar up and down, and the needle bar drive member is rotated to its drive release position to interrupt the drive force transmission from the needle bar drive member to the needle bar. In a needle bar drive releasing device of a multi-head sewing machine configured to lean, a cam surface formed flat with respect to the needle bar drive member in the vertical direction, and a needle bar drive member engaged with the cam surface. A drive releasing mechanism configured to be rotatable to the drive releasing position and lockable in the operating state, wherein the vertical length of the cam surface is the entire vertical stroke of the needle bar drive member. 2. The needle bar drive releasing device for a multi-head sewing machine, wherein the dimension is set so that the engagement with the drive releasing mechanism is maintained.