JPS5941806Y2 - Structure of sewing machine thread tension regulator - Google Patents

Description

[Detailed explanation of the idea] (Technical field) The present invention relates to the structure of a thread tension regulator for a sewing machine.

(Prior Art) In the conventional thread tension device, it was difficult to provide the scale portion of the adjustment dial and the member providing the indicator line for the scale portion in the same unit.

In addition, the mechanism for loosening the thread when the presser foot is raised is
Since the structure was such that a thread loosening pin, which was activated via a link mechanism by lifting the presser foot, was inserted into a small hole formed along the axial direction of the thread tension shaft, the processing costs for the small hole increased, and The disadvantage was that the configuration was complicated.

Furthermore, there is a drawback that setting the reference tension when assembling the thread tension device requires a relatively large number of man-hours.

(Purpose) The purpose of the present invention is to provide a member with an indication line for the scale part of the thread tension dial in close opposition to each other in the same unit of the thread tension device, thereby improving the ease of use. To make it easier to check the thread tension, to simplify the mechanism for loosening the thread when the presser foot is raised, and to make it easier to set the reference tension when assembling the thread tension device compared to conventional ones. That's true.

(composition) The present invention will be explained below with reference to examples.

Thread tension shaft 3 fixed to machine frame 1 of the sewing machine with screws 2, etc.
A pair of thread tension discs 4 and 5, an intermediate disc 6 located between these discs, and a plurality of protrusions 8a formed at one end are brought into contact with the thread tension disc 4 at the base end 3a of the thread tension disc 4. Machine frame 1
It is stopped from rotating via pin 7 and has an indicator line 8 on the outer periphery.
A plate holder 8 provided with b is fitted.

Reference numeral 1a denotes a projection formed on the machine frame 1 to prevent the upper thread from entering the right side of the thread tension disc 5 when the upper thread is threaded.

The inner diameter part 9c of the thread tension dial 9 corresponds to the boss part 8c of the tray receiver 8.
It is rotatably fitted into the housing, and its axial position is regulated by a removal preventing member 10.

The scale portion 9a of the thread tension dial 9 is closely opposed to the indicator line 8b in the assembled state.

Reference numeral 11 denotes an auxiliary spring disposed between the stepped portion 3b of the thread tension shaft 3 and the plate receiver 8.

The spring guide 12, which is an adjustment member, is fitted onto the thread tension shaft 3 and has a plurality of grooves 12b formed on the outer periphery of the flange portion 12a.
9 and a part 9 formed on the inner periphery of the thread tension dial 9.
b is engaged with the guide groove 12c, and the protrusion 14a of the adjustment nut 14 fitted into the threaded portion 3c of the thread tension shaft 3 and used to adjust the thread tension spring 13 is engaged with the guide groove 12c. The tip of a thread loosening lever 16 pivotally supported on a shaft 15 is engaged with the flange portion 12d.

Although not shown, the thread loosening lever 16 is connected to the presser foot lifter by a link mechanism.

(Operation) Next, the operation of the present invention configured as described above will be explained.

To set the reference tension when assembling the thread tension device, first press the spring guide 1 with your fingers against the biasing force of the thread tension spring 13.
2 to the left in FIG.
Disengage from the

Next, in this state, the adjusting nut 14 is inserted through the spring guide 12.
This can be easily carried out without using any tools by adjusting the rotation as appropriate, re-engaging the groove 12b and the key portion 9b at that position, comparing the tension with the reference tension, and repeating this operation.

To adjust the upper thread tension when using the sewing machine, when the thread tension dial 9 is rotated, the adjustment nut 14 is rotated through the key portion 9b, the groove 12b, and the guide groove 12C, and the thread tension spring 13 is attached. The force is adjusted, and the biasing force is transmitted to the thread tension discs 4 and 5 via the spring guide 12 and the disc holder 8, and the thread clamping pressure between the discs is adjusted.

In this case, since the scale portion 9a and the indicator line 8b are closely opposed to each other, it is easier to check the needle thread tension compared to the conventional example.

When the presser foot lifter is raised, the thread loosening lever 16 is rotated counterclockwise in FIG.
2 is moved to the left in FIG. 1, the spring guide and the plate receiver 8 come out of contact, and the thread clamping pressure between the thread tension plates 4 and 5 by the thread tension spring 13 is released.

(Effects) As described above, according to the present invention, by arranging the plate receivers with indicating lines for the scale part of the thread tension dial so as to be close to each other in the same unit of the thread tension regulator, it is possible to This has the effect of making it easier to check the needle thread tension, and since the thread loosening mechanism has a structure in which the thread loosening lever is engaged with the flange, it is no longer necessary to insert the thread loosening bottle into the thread tension shaft of the conventional example. This has the effect of requiring fewer machining steps and simplifying the configuration compared to the conventional method, and the reference tension can be set without the use of tools when assembling the thread tension device. This has the advantage of being easier to perform than.

[Brief explanation of drawings]

The drawings relate to an embodiment of the present invention, and FIG. 1 is a front view of the thread tension device, FIG. 2 is a longitudinal sectional view of the thread tension device, and FIG. 3 is an exploded perspective view of the main parts of the thread tension device. 1 is the machine frame, 3 is the thread tension shaft, 3c is the screw part, 4°5 is the thread tension disc, 6 is the middle disc, 8 is the disc holder, 8b is the indicator line, 8c is the boss part, 9 is the thread tension dial 9a 9b is a scale part, 9c is an inner diameter part, 12 is a spring guide which is an adjustment member, 1
2a and 12d are flange portions, 12b is a groove, 12C is a guide groove, 13 is a thread tension spring, 14 is an adjustment nut, and 16 is a thread loosening lever.

Claims (1)

[Scope of utility model registration request] A pair of thread tension discs, an intermediate disc located between the thread tension discs, and a thread tension spring that applies thread clamp holding pressure to the thread tension discs are fitted onto a thread tension shaft fixed to a machine frame. In the thread tension device equipped with a thread tension dial that continuously adjusts the pressure of the thread tension spring, the thread tension dial is fitted onto the thread tension shaft, one end of which is brought into contact with the thread tension disc, and is prevented from rotating with respect to the machine frame. is,
a plate holder 8 whose boss is fitted inside the thread tension dial and allows the thread tension dial to rotate; and one of a plurality of grooves formed on the outer periphery with one end abutting the boss of the iron blood receiver. is formed near the middle of the flange portion that engages with a part of the inner wall of the thread tension dial, and engages with a protrusion of an adjustment nut fitted into the threaded portion of the thread tension shaft, and rotates together with the thread tension dial. A structure of a thread tension regulator for a sewing machine, comprising an adjusting member 12 having a guide groove and a flange portion at the other end with which a thread loosening lever engages.