JPS5850988A - Upward sending mechanism of sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an upper feed mechanism of a sewing machine.

Conventionally, as shown in Fig. 1, oval sewing machines and the like have been known to have an upper feed mechanism that feeds the cloth through four movements in cooperation with a lower feed dog (II not shown) to improve the feeding force of the cloth. There is.

This upper feed mechanism has a presser foot at the tip as shown in Figure 1.
a presser foot arm 2 having a presser foot arm 2, and a bottle 8. An upper feed arm 5 that is swingably supported by the bin 4 and has an upper feed tooth 5A at its tip; a bin 6 provided with an upper feed 1Ii5AK;
a support body 7 that fits with the upper feed dog 5A and provides four movements to the upper feed dog 5A;
It is composed of a spring S that presses the support body 7 downward and applies a constant pressing force to the upper feed dog 5A.

In addition, the top feed dog 5A prevents the bottle 6 from coming out of the support 7 and moving together with the presser foot 12 as the presser foot arm 2 rotates about the axis NASA. It has the advantage of making work easier.

However, since the support body 7, the upper feed arm 5, and the hook 6 are used for fitting connection, when the sewing machine is driven, the loads of both the support body 7 and the upper feed arm 5 act on the sewing ring S.
In particular, when the sewing machine is rotated at high speed, the inertia force due to the above-mentioned load increases and the five upper feed teeth jump, making it impossible to obtain an appropriate feed force.

The object of the present invention is to provide an upper feed mechanism for a sewing machine that can eliminate such drawbacks. An embodiment of the present invention will be described below with reference to the drawings. , In FIG. 2, reference numeral 11 denotes a cloth presser arm, the rear base of which is rotatably connected to the support portion 12 & of the presser arm support 1z by a pin 1B having a vertical axis, and the presser arm support 12 is integrally A shaft portion 12b having a horizontal axis formed in the horizontal direction is rotatably supported on a machine frame (not shown).

Reference numeral 15 denotes a presser foot provided at the tip of the presser arm 11, and this presser foot λ5 has two holes 15b and 15b formed in the forward direction 1 in the cloth feeding direction from the needle drop hole 15a.

Reference numeral 16 denotes an upper feed arm, whose rear forked portion 17 is loosely fitted into a collar 18 provided on the side end surface of the presser arm 11, and a collar provided with a play hole 19 formed in the front on the side end surface of the presser arm 11. It is loosely fitted to 20. For this reason, the upper feed arm 16 can swing around the collar 18 along the side of the presser arm 11.

21.29 is a washer for supporting the upper feed arm 16 on the presser arm 11.

28 is an upper feed dog provided at the tip of the upper feed arm 16, and the pair of feed teeth 28.28 are connected to both upper feed holes 1 of the presser foot 15.
5b and 15b.

Reference numeral 24 cooperates with a lower feed dog (not shown) that moves back and forth in and out of the throat plate (not shown), and feeds the cloth by interlocking with a driving shaft (not shown) above the throat plate. This rocking body 24 and the upper feed arm 16 are
They are connected by a vertically elongated hole 25 provided in the body 24 and a pin 26 provided in the upper feed arm 16 that fits into the elongated hole 25 so as to be able to move vertically.

Therefore, the upper feed arm 16 makes four movements by following the four movements of the rocking body 24, and the bottle 26 moves through the vertical hole z5 in response to the vertical movement acting on the upper feed dog 28.
27 acts on the upper surface of the upper feed arm 16. , is a pressing body that always has an acting force that presses the upper feed dog toward the throat plate, and brings the lower end roller 2'7a into contact with the upper surface of the upper feed arm 16, and also presses the upper part against the machine frame (not shown). The upper feed arm 1
6 is pressed downward.

Alternatively, the bin z6 may be provided in the swinging body 24, and the vertically elongated hole 25 may be bored in the upper feed arm 16.

Next, we will explain the details of this invention.

In FIG. 2, when the sewing machine is driven, the needle moves up and down as is well known, although not shown, and the lower feeder also makes four movements for feeding the fabric. The rocking body 24 is also linked to the sewing machine mechanism,
The vertically elongated hole z5 at the tip is in the opposite phase to the vertical movement phase of the lower feed dog, that is, when the lower feed dog rises, it descends and then moves in the cloth feeding direction, and when the lower feed 91m descends, it rises. 4 movements in the direction opposite to the cloth feeding direction.

The four movements of the vertically elongated hole 25 are transmitted to the upper feed arm 16 via the pin 86. The four movements of this vertically elongated hole 25 and the pressing body z
7, the upper feed arm 16 moves to the rocking body 24.
The two-pronged ml at the end in synchronization with the four movements of? is color 18
The lower surface of the upper feed dog 10 at the tip presses the cloth against the upper surface of the throat plate by rotating clockwise around the center. Then, when the vertical hole 25 moves in the cloth feeding direction, the fork 17 slides on the collar 18. Then feed the cloth using the upper feed dog 2B and the lower feed dog, and then feed the cloth through the vertical hole 2.
5 rises, the two prongs 17 resist the pressing force of the pressing body 27.
rotates counterclockwise around collar 18 and upward feed $2
8 rises from the cloth, and then when the vertical hole 25 moves in the opposite direction to the cloth feeding direction, the forked part 17 slides on the collar 18, and the upper feed #2B returns to its original position, and the upper feed #2B returns to its original position. The feed dog 28 performs four cloth feeding movements.

The upward and downward "negation" of the upward feed l1lt2B during the four movements is taken care of by the pressing body 27 and the vertically elongated hole 25, but since the pressing body 27 acts only on the upward feeding arm 16, The load acting on the pressing body 27 is lighter than that of the conventional one, and even at high speed rotation, the load applied to the pressing body 27 is reduced by 1 tj, +11 dollars.
This prevents the male from jumping against the tin ring S of the pressing body 27.

In addition, when changing the needle or threading the needle, place the needle in the raised position and operate the well-known pressure release lever to release the pressure body 27.
When the presser foot arm 11 is rotated to the left around the bin 1B after being raised from the upper feed arm 16, the upper feed dog 2B
The upper feed arm 16 with the upper feed arm 16 also rotates, thereby releasing the fit between the vertical hole 25 and the bottle 26, and the presser foot 15 and the upper feed dog 28 move to a position away from the sewing machine sewing part. Change the needle or thread the thread in this state.

After completing the work, move the presser foot arm 11 to the bin 18 in the opposite direction to the above.
Rotate centering around , fit the bottle 26 into the vertical hole 25, and operate the pressure release lever to release the pressing body 2? When the presser foot 15 and the upper feed dog 28 are lowered to the upper surface of the upper feed arm 16, the presser foot 15 and the upper feed dog 28 return to their original positions, and the cloth can be fed by the upper feed dog 28.

As described above, according to the present invention, since the pressing body acts only on the upper feeding arm equipped with the upper feeding dog, the load acting on the pressing body during high-speed operation can be reduced and the discharge volume can be reduced. Therefore, the upper feed dog works with the lower feed dog to feed the fabric at an appropriate pitch and feed force, which eliminates uneven stitching and fabric misalignment. .

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a conventional upper feed mechanism, and FIG. 2 is an exploded perspective view showing a practical example of the upper feed mechanism according to the present invention. 11... Presser arm 16... O upward deflection arm 24... Rocking body 27... Pressing body

Claims (1)

[Scope of Claims] A lower feed #IK that is linked to a driving shaft above the throat plate and moves back and forth in and out of the throat plate; a rocking body that moves four times so as to pinch and feed cloth in cooperation;・A presser foot arm with its base end rotatably supported on a vertical shaft provided in the machine frame so that the presser foot with a lower through hole faces or faces the sewing part, and the base end is attached to the presser foot arm. It is supported movably with oil in the direction of cloth feed, and the middle part is opposed to or separated from the seam part of the presser foot. 1. The upper feed arm is attached to or detached from the moving body and is supported on the oscillating body so as to be able to move up and down, and the upper feed arm supports the upper feed dog facing the upper and lower through holes of the presser foot at the tip, and the 1 upper feed arm is always attached to the throat plate. The upper feed mechanism of a sewing machine consists of a pressing body that has an elastic force that presses in a direction.