KR100546107B1 - Sewing machine with removable bearing bush - Google Patents

Abstract

The sewing machine comprising a bearing bush 8 detachably fixed to the housing bore hole 9 for supporting components such as the sewing presser 6 and the needle bar 4 is provided with the long axis A of the housing bore hole 9. ) Two bore holes (10, 10 ') parallel to the housing bore hole (9), the transverse bore holes (11, 11') and the cross bore holes in contact with the bore holes (10, 10 ') Cylinder pins 13, 13 ′ inserted into respective boreholes 10, 10 ′ tightened in the circumferential direction of the bearing bush 8 by tightening devices 12, 12 ′ inserted into the 11, 11 ′. Characterized in having a.

Sewing machine, borehole, transverse borehole, cylinder pin, bearing bush.

Description

Sewing machine with removable bearing bushes {Nahmaschine mit losbar befestigter Lagerbuchse}

1 is a front view of a sewing machine according to the present invention,

2 is a cross-sectional view taken along the line II-II of FIG.

3 is a view similar to that of FIG. 2, illustrating a state in which a bearing bush and a cylinder pin are not mounted;

4 is a partial longitudinal section of the bearing bush,

5 is a view showing a cylinder pin,

FIG. 6 is a view illustrating a state observed in the arrow VI direction of FIG. 1.

The present invention relates to a sewing machine including a bearing bush detachably fixed to a housing bore hole for supporting a part (sewing press bar, needle bar).

Sewing machines of this type have already been known, for example, from DE-PS 10 90 942 (US Pat. No. 2,921,545). The bearing bush is secured to a housing bore hole installed in the machine arm via a removable screw anchor. In addition, the front of the machine arm is provided with a screw hole that proceeds transverse to the housing bore hole and terminates in the housing bore hole, and a fixing screw is inserted into the screw hole.

In order to accurately align the bearing bush in the housing bore hole, a specific fitting, i.e., a precise manufacturing tolerance, must be premised, which increases the manufacturing cost. If the fittings are too narrow, assembly or disassembly is difficult because the parts move only by corresponding forces.

Tighten the tightening screws to prevent the bearing bush from moving when the sewing presser moves up and down during machine operation. To ensure sufficient maneuverability in emergencies, the bearing bush is made of a weak material, for example bronze. However, if the tightening screw is tightened too tightly, the bearing end is damaged due to the screw end presses the bearing bush, which may cause difficulty in detaching the bearing bush from the sewing machine during repair. Another disadvantage is that it can be deformed by the force applied to the bearing bush itself (reverse force exerted in the opposite direction to that by the screw), which can weaken the bearing force.

In order to prevent such damage of the bearing bush, a method of adhering the bearing bush to the housing bore hole has been attempted. The disadvantage of this method is that it is very difficult to treat the bonding site to ensure safe bonding. Another disadvantage associated with this bonding method is the difficulty of replacing the sewing presser or the bearing bush. The adhesive can only be removed when a large force is applied. If too much force is applied to the end of the bearing bush protruding from the machine arm, the bearing bush or the sewing presser may be damaged.

As mentioned above, attempts have been made to design the sewing machine so that the bearing bush is not removed from the machine housing as much as possible due to problems associated with securing the bearing bush to the sewing machine housing. However, this acts as a disadvantage in designing the sewing presser accommodated in the bearing bush since the assembly and separation of the sewing presser received in the bearing bush should be made only at the upper end of the bearing bush. Therefore, other parts of the machine housing must be disassembled to access the bearing bush.

In order to solve the above problems, the sewing machine according to the present invention can simply detach the bearing bush, no other special fittings are required between the bush and the housing bore hole, and are not damaged when fixing the bearing bush. do.

The sewing machine according to the present invention is characterized by two bore holes parallel to the long axis of the housing bore hole and in contact with the housing bore hole, a transverse bore hole in contact with the bore hole and a tightening device inserted into the transverse bore hole. It has a cylinder pin inserted into each bore hole tightened in the circumferential direction.

Due to this structure, the bearing bush or the housing bore hole accommodated therein can be manufactured with free tolerance, and the parts can be easily accessed without using other unnecessary force during assembly or disassembly. Therefore, assembly or disassembly is quick and simple. In addition, since the cylinder pin is pressed to the bearing bush through line contact, the risk of deformation is significantly reduced, unlike in the case of point contact.                         

When the cylinder pin is pressed against the bearing bush, the cylinder pin is first pushed to the opposite side of the housing bore hole and here it is moved to the support surface via line contact. Thus, the bearing bush is supported by three lines distributed around it, which allows the bearing bush not only to be securely and firmly fixed but also to be accurately aligned.

Another advantage of the present invention is that it can be based on a bearing bush that can be assembled or disassembled simply and quickly in the design of the bearing bush and the sewing presser accommodated therein.

Another advantage of the present invention is that the thread is formed at least partially in the cross bore hole so that the screw can be used as a tightening device.

In addition, when the cylinder pin is inserted into the bore hole in the state having a clearance, the tightening device is released and then separated together with the bearing bush, there is no risk of deformation due to excessive force during separation.

The sewing machine according to the invention has a housing which is spaced from the stander 2 and protrudes from the table 1, the arm 3, the table 1 and the stander 2. The arm 3 has a needle bar 4 to which the needle 5 is fixed at the lower end, and a sewing material press bar 6 including a carrier plate 7 fixed at the lower end to be vibrated. It is fixed to be possible. The sewing presser 6 operates in a removable bearing bush 8 installed in the housing bore hole 9.

Two bore holes 10, 10 'are installed in the base of the arm 3 parallel to the longitudinal axis A of the bearing bush 8, and the center point of the bore holes 10, 10' is the bore. The holes 10 and 10 'are adjacent to the center point of the bore hole 9 such that they are in contact with the bore hole 9 (see Fig. 3). On the right side of the bore holes 10, 10 ′ two transverse bore holes 11, 11 ′ are provided, which end in the bore holes 10, 10 ′. Inner cross threads are formed in at least a portion of the transverse bore holes 11 and 11 'to tighten the screws 12 and 12'. The bore holes 10, 10 'are inserted with (commercially) cylinder pins 13, 13'.

When the screws 12 and 12 'are tightened, the bearing bush 8 inserted into the housing bore hole 9 is pressed against the side wall of the housing bore hole 9 via the cylinder pins 13 and 13' ( 2). At this time, the cylinder pins 13 and 13 'come into contact with the bearing bush 8 along one line. In the housing bore hole 9 the bearing bush 8 is supported along one line on the opposite side of the cylinder pins 13, 13 ′. Thus, the bearing bush 8 is fixed by three lines in the circumferential direction.

There is a clearance between the bearing bush 8 and the housing bore hole 9. The present invention allows the outer diameter of the bearing bush 8 and the housing bore hole 9 to be manufactured with relatively large manufacturing tolerances, respectively, to reduce manufacturing costs. The cylinder pins 13 and 13 'are fixed to the corresponding bore holes 10 and 10' in a state having a clearance. When the screws 12 and 12 'are loosened, the cylinder pins 13 and 13' and the bearing bush 8 can be separated from the housing. Therefore, the bearing bush 8 and the sewing material pressing stand 6 can be replaced in a short time.

As described above, the sewing machine according to the present invention can manufacture a bearing bush or a housing bore hole accommodated therein at a free tolerance, and can easily access the parts without using other unnecessary force during assembly or disassembly. The assembly or disassembly is quick and simple, and since the cylinder pin is pressed to the bearing bush through line contact, the risk of deformation is significantly reduced, unlike in the case of point contact.

Claims (4)

In a sewing machine comprising a bearing bush (8) detachably fixed to a housing bore hole (9) for supporting components such as a sewing presser (6) and a needle bar (4), Two bore holes 10, 10 ′ parallel to the long axis A of the housing bore hole 9 and in contact with the housing bore hole 9, Transverse bore holes 11, 11 ′ in contact with the bore holes 10, 10 ′ and A cylinder pin inserted into each bore hole 10, 10 'which is tightened in the circumferential direction of the bearing bush 8 by means of fastening devices 12, 12' inserted into the transverse bore holes 11, 11 '; 13, 13 ') sewing machine. 2. Sewing machine according to claim 1, characterized in that the thread is formed at least partially in the transverse borehole (11, 11 ') and a screw is used as the tightening device (12, 12'). 2. Sewing machine according to claim 1, characterized in that the cylinder pin (13, 13 ') is inserted in the borehole (10, 10') with a clearance. 2. Sewing machine according to claim 1, wherein there is a clearance between the bearing bush (8) and the housing bore hole (9).

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