JPH0135729Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a feed dog lowering mechanism that works in conjunction with a presser foot that presses down cloth, and lowers the feed dog from above the throat plate when the presser foot is raised.

Prior Art In ordinary sewing machines other than needle-feed sewing machines, the feed dog is raised above the top surface of the throat plate when the needle bar is raised. Fourth
The figure is a perspective view of the feed dog mechanism of this normal sewing machine.
A vertical eccentric cam 2 is mounted on the upper shaft 1, and a vertical rod 3 of the vertical eccentric cam 2 is connected to a vertical rod pin 6 of a square piece 5 that slides in a groove 4' of an adjusting body 4. One end of the vertical feed link 7 is connected to the vertical rod pin 6, and the vertical feed link 7
The other end is connected to a vertical feed fork 10 connected to a vertical feed shaft 9 via a vertical feed arm 8 . The square separator 11 of this upper and lower feed fork 10 is connected to a feed dog 12. On the other hand, the feed base 13 of the feed dog 12
is connected to the horizontal feed shaft 14.

In the feed dog mechanism configured in this way, when the upper shaft rotates, the upper and lower eccentric cams 2 rotate, and the square sesame 5 is moved up and down in the groove 4' of the adjustment body 4 via the upper and lower rods 3. Accordingly, the vertical feed link 7,
Rotate the vertical feed arm 8 and the vertical feed fork 10,
This also moves the feed dog 12 up and down. At this time, the horizontal feed shaft 14 rotates to move the feed table 13 horizontally, thereby causing the feed dog 1
2 is moved horizontally, and the above vertical movement and this horizontal movement cause an elliptical movement, which causes the feed dog 1 to move horizontally.
You can send the cloth with 2. In addition, the upper and lower rods 3
When the needle is raised, the feed dog 12 is also raised above the throat plate, and at this time the needle bar (not shown) is raised.

Problems to be Solved by the Invention However, when the feed dog 12 is raised above the top surface of the throat plate, the work of loading and unloading the cloth is carried out, but this feed dog 12 is not fixed as shown in Fig. 2. Since it has a tooth shape, it gets caught on the feed dog 12 when putting in and taking out the cloth, making it difficult to put in and take out the cloth. In particular, when using thick or non-slip fabrics, they tend to get caught on the feed dog 12, making it even more difficult to take them in and out.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention has a vertical eccentric cam attached to the upper shaft, which is connected to the square separator of the adjustment body through the upper and lower rods, and the upper and lower eccentric cams are connected to the square separator from the square separator. In a feed drive mechanism that is connected to a feed dog via a feed link, a vertical feed arm, and a vertical feed fork, and converts rotation of the upper shaft into vertical movement of the feed dog, the adjustment body is provided with an adjustment body link, and the adjustment body is provided with an adjustment body link. When the body link is brought into contact with the cam and the presser foot lifting bar that is linked to lifting the presser foot is raised, the cam is rotated to push down the adjusting body link, and the adjusting body is rotated to raise the vertical feed link. , the vertical feed arm and the forked link are rotated to lower the feed dog.

Function According to the present invention, by raising the presser foot lifting push bar in conjunction with raising the presser foot, the adjusting body can be rotated, thereby lowering the feed dog, so that the needle bar is raised. Cloth can be taken in and out when the feed dog is below the throat plate, so the cloth does not get caught on the feed dog, making it easy to put in and take out even thick or non-slip fabrics.

Embodiment Fig. 1 is a side view of a part of the feed dog lowering mechanism according to an embodiment of the present invention, in which 1 is an upper shaft, 2 is an upper and lower eccentric cam, 3 is an upper and lower rod, and 4 is rotatable on the sewing machine body. 5 is a square sesame, 6 is a vertical rod pin, 7 is a vertical feed link, 8 is a vertical feed arm, 9
is a vertical feed shaft, and since the configuration thereof is the same as that of the conventional example shown in FIG. 2, a description thereof will be omitted. , is brought into contact with the contact portion 17a of the cam 17 that rotates around the fixing pin 16. The protruding portion 17b of the cam 17 is in contact with a push rod piece 19 of a presser foot lifter push rod 18, which has one end that is interlocked with a presser foot that presses down the cloth. This presser foot lifting push rod 18
The other end is connected to the oil pan 20 to facilitate sliding of the presser foot lifting push rod 18. Also, the adjustment body 4
An arm 21 is provided at an opposing portion of the adjustment body link 15, and a spring 22 is provided on this arm 21, and presses the adjustment body link 15 so as to always bring it into contact with the contact portion 17a of the cam 17.

In the feed dog lowering mechanism of this embodiment configured as described above, the upper and lower rods 3 are raised as shown in FIG. 2, and the square piece 5 is located above the groove 4' of the adjustment body 4 When the presser foot is raised and the presser foot lifting push bar 18 is raised as shown in FIG. , the cam 17 rotates, and the contact portion 1
7a to lower the adjustment body link 15, thereby rotating the adjustment body 4. When this adjusting body 4 rotates, the length of the upper and lower rods 3 does not change, so the square separator 5 that was located above the groove 4' of the adjusting body 4 is Adjustment body 4
lower to the center position. Therefore, the vertical feed link 7 is pushed in the direction of the vertical feed arm 8,
Therefore, the feed dog 12 is lowered.

In the above embodiment, the feed dog is lowered in conjunction with the lifting of the presser foot, but the adjustment body 5 is rotated when the edge of the fabric being sewn is detected by the fabric edge detector. The feed dog 12 may be lowered so that the amount of cloth feed can be adjusted by moving the feed dog.

Effects of the invention As is clear from the above explanation, the present invention is capable of lowering the adjusting body by raising the presser foot lifter bar in conjunction with lifting the presser foot, thereby lowering the feed dog. , when the needle bar and presser foot are raised, the feed dog is lowered below the throat plate, and the fabric can be taken in and out in such a state, so the fabric does not get caught in the feed dog and can be used for thick fabrics. This has the advantage that even non-slip cloth can be easily put in and taken out.

[Brief explanation of drawings]

Fig. 1 is a front view of a feed dog lowering mechanism according to an embodiment of the present invention, Figs. 2 and 3 are diagrams for explaining the principle of the feed dog lowering mechanism shown in Fig. 1, and Fig. 4 is a view of a conventional feed dog lowering mechanism. It is a schematic perspective view of a feed dog drive mechanism. 1...Upper shaft, 2...Vertical eccentric cam, 3...Upper and lower rod, 4...Adjusting body, 5...Square sesame, 6...Upper and lower rod pin, 7...Upper and lower feed link, 8...Upper and lower feed arm , 9... Vertical feed shaft, 15... Adjustment body link, 16... Fixed pin, 17... Cam, 17a
. . . Contact portion, 17b . . . Projection portion, 18 . . . Presser foot lifting push rod, 19 .

Claims (1)

[Scope of utility model registration request] A vertical eccentric cam is attached to the upper shaft, and is connected to the square separator of the adjustment body through the upper and lower rods, and from the square separator is connected to the feed dog via the vertical feed link, the vertical feed arm, and the vertical feed bifurcation, and the upper In the feed drive mechanism that converts rotation of the shaft into vertical movement of the feed dog, the adjustment body is provided with an adjustment body link, and the adjustment body link is brought into contact with a cam to raise a presser foot lifting push rod that is linked to the presser foot lifting. When the cam is rotated to push down the adjustment body link, the adjustment body is rotated to rotate the vertical feed link, the vertical feed arm, and the bifurcated link to lower the feed dog. Feed dog lowering mechanism featuring: