JPS6115810Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vertical full-rotation hook for a lockstitch sewing machine.

Conventionally, in a vertical full-rotation hook, the rotation of the inner hook is restrained by an inner hook rotation preventing member fixed to the body of the sewing machine. At this time, when the looped needle thread passes through the contact point between the inner hook and the inner hook, the contact pressure is unstable, resulting in variations in the tension of the needle thread, and as a result, the thread This caused breakage and poor thread tightness.

Therefore, when the upper thread passes through the contact point,
Conventionally, an opener mechanism has been adopted in which the inner hook is slightly angularly displaced by a collision piece in the opposite direction to the rotating direction of the outer hook, thereby creating an instantaneous gap at the contact point. There is.

In such prior art, the inner hook is angularly displaced by a mask and a collision piece that allows the needle thread to pass smoothly through the interval formed between the contact points, so that the interval is obtained. It is impossible to avoid the sound of collision between the inner rotor and the inner rotor and the collision between the inner rotor and the inner rotor.

The purpose of this invention is to solve the above-mentioned technical problems, and to use an innovative structure to smoothly pass the upper thread between the inner hook and the inner hook rotation prevention member without force or noise. To provide a vertical full-rotation hook for a lockstitch sewing machine, which enables the sewing machine to rotate the lockstitch sewing machine.

To summarize, the present invention interposes an eccentric bearing cylinder between the lower shaft and the outer hook of the sewing machine, and by shifting the axis of rotation of the lower shaft and the outer hook, the contact between the outer hook and the outer hook is prevented. There is a full vertical rotary hook in which the inner hook is swung along a plane to allow the needle thread to separate without any tension.

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the section of FIG. An inner hook 2 is attached to the outer hook 1 while allowing rotation of the outer hook 1. The inner hook 2 is prevented from rotating when the outer hook 1 is rotated by an inner hook rotation prevention member 3 fixed to the body of the sewing machine. A bobbin case (not shown) containing a bobbin wound with a bobbin thread is housed within the inner hook 2.
A through hole 4 as a needle drop portion is formed on the outer periphery of the inner hook 2, and an engaging pawl 5 formed at the free end of the inner hook rotation prevention member 3 is engaged near the through hole 4. A recess 6 is formed.

A cylindrical shaft joint 7 is provided on the bottom of the outer hook 1 to protrude coaxially with the rotational axis of the outer hook 1. The shaft coupling 7 has a plurality of screw holes 11, 1 spaced at equal intervals in the circumferential direction.
2 and 13 are formed, and these screw holes 11 to 1
3 are individually screwed into screws 14, 15, and 16.
The screws 14 to 16 are located in the same plane perpendicular to the axis of rotation, and each tip thereof is arranged facing a screw receiving portion 17 of the bearing sleeve 8, which will be described later.

A rigid bearing sleeve 8 is mounted within the shaft joint 7 coaxially with the rotational axis. The bearing cylinder 8 is composed of a cylindrical screw receiving portion 17 and outward flanges 18 and 19 formed at both ends of the screw receiving portion 17 along the axis thereof, respectively. The center line 20 of the shaft hole 9 of the bearing sleeve 8 is offset from the axis 21 of the bearing sleeve 8 by a distance d, as shown in FIG. This center line 20 is the shaft joint 7
It coincides with the center of the circular outward facing flanges 18, 19 which fit snugly inside. The tip of a rotating shaft 10 of a sewing machine is fitted into this shaft hole 9. Thereafter, the screws 14 to 16 of the shaft coupling 7 are rotated to displace the tips of the screws 14 to 16 toward the screw receiving portion 17 of the bearing sleeve 8. Screw receiving part 17
As shown in FIGS. 4 and 5, the cross section perpendicular to the axis is formed into a thin ring shape, and the screw 1
It is deformed as shown by the imaginary line 22 by the tightening force of 4 to 16. By press-contacting the screw receiving portion 17 to the rotating shaft 10 in this manner, the bearing sleeve 8 can be integrally attached to the rotating shaft 10.

In this way, since the rotating shaft 10 is tightened by the screws 14 to 16 through the bearing sleeve 8, the rotating shaft 10 is depressed by the direct pressure contact of the tips of the screws 14 to 16. can't be hurt. Therefore, when attaching and removing the outer hook 1 to and from the rotating shaft 10, it is possible to prevent difficulty in positioning the outer hook 1 due to the recess of the rotating shaft 10.

Referring to FIG. 6, the operating state of the vertical rotary hook according to the present invention will be described below. The outer hook 1 is rotated by the action of the bearing sleeve 8 about an axis parallel to the axis of rotation of the rotating shaft 10 and offset by the eccentricity value d. This eccentric rotation of the outer hook 1 causes the inner hook 2 fitted in the outer hook 1 to swing. Specifically, the inner hook 2 sequentially moves downstream (upward in FIG. 6) and upstream (downward in FIG. 6) in the rotational running direction 27 of the outer hook 1.

At the time when the needle thread loop passes between the inner hook abutment surface 25 formed on the inner hook 2 and the rotation prevention abutment surface 26 formed on the inner hook rotation prevention member 3, the eccentric rotation of the outer hook 1 occurs. The inner pot 2 is moved to the upstream side by the movement. Such timing can be adjusted by changing the mounting state of the bearing sleeve 8. In other words, the bearing tube 8 is connected to the shaft coupling 7 of the outer hook 1.
When the bearing sleeve 8 is mounted on the shaft, the shaft hole 9 is positioned, for example, at position a shown in FIG. 7 by angularly displacing the bearing sleeve 8 about its axis. When the outer hook 1 is attached to the rotating shaft 10 in this attached state, the time point at which the needle thread passes through can be made to coincide with the time point at which the inner hook 2 moves toward the upstream side.

After passing through the needle thread loop, the inner hook 2 is returned to the downstream side, and the inner hook contact surface 25 and the detent contact surface 26 come into contact with each other.

By changing the mounting state of the bearing tube 8 in this way, it is possible to adjust the timing between the passage of the needle thread and the swinging of the inner hook 2.

The eccentricity value d of the bearing sleeve 8 is arbitrarily selected depending on the width of the swinging range of the inner hook 2.

As another embodiment of the present invention, as shown in FIG. 8, a driver groove 30 may be formed on the outward flange 19 of the bushing 8 along one diameter line. This facilitates angular displacement of the bearing sleeve 8 attached to the shaft coupling 7 about the axis.

The present invention can be used not only for vertical full-rotation hooks but also for horizontal full-rotation hooks.

As described above, according to the present invention, due to the function of the eccentric bearing cylinder, when the needle thread loop passes between the inner hook abutment surface and the detent abutment surface, the inner hook is moved from the outer hook to the outer hook. Since it is arranged to move upstream in the rotational running direction, the needle thread loop can be passed smoothly without generating noise. Furthermore, simply by angularly displacing the bearing cylinder around the axis, it is possible to adjust the timing between the passage of the needle thread and the time of movement of the inner hook upstream, thereby improving work efficiency.
Moreover, since the bearing sleeve is interposed between the outer hook and the rotating shaft, the rotating shaft is prevented from being damaged by the fixing screw of the outer hook. The receiving part 17 is thin, so the screw receiving part 17 is deformed by the tips of each of the screws 14 to 16 to be brought into pressure contact with the rotating shaft 10, and thus the outer hook 1 and the rotating shaft 10 are fixed. Can be done. This can prevent damage to the rotating shaft 10 caused by the screws 14 to 16 as described above.

The bearing cylinder 8 has outward flanges 18 and 19 formed at both ends of the axis of the screw receiving part 17, and these outward flanges 18 and 19 are circular so that they fit snugly into the shaft coupling 7. With the rotary shaft 10 fitted into the shaft hole 9 of the bearing sleeve 8, and without tightly screwing the screws 14 to 16, the outer hook 1 and the rotary shaft 10 are roughly positioned relative to each other. Therefore, positioning adjustment is easy. In this rough positioning state, screw 14
The outer hook 1 and the rotating shaft 10 can be fixed by lightly abutting the tips of the screws 14 to 16 against the outer peripheral surface of the screw receiving portion 17, and then tightening the screws 14 to 16 with the same torque. . In this way, positioning can be performed accurately and easily.

Screw holes 11, 12 into which screws 14 to 16 are screwed,
13 are formed at equal intervals in the circumferential direction of the shaft joint 7 and in the same plane perpendicular to the axis of rotation, so by setting the same torque of the screws 14 to 16, the shaft joint 7 The outer hook 1 and the rotary shaft 10 can be fixed using the screws 14 to 16 while the outer hook 1 and the rotary shaft 10 are still positioned relative to each other by the angular displacement of the bearing sleeve 8, thereby improving workability.

Furthermore, in the present invention, the bearing sleeve 8 has outward flanges 18 and 19 formed at both ends of the axis of the screw receiving portion 17, so that the tip portions of the screws 14 to 16 can be screw received. It is possible to reliably abut on the portion 17, and erroneous abutment on the rotating shaft 10 can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the present invention, Fig. 2 is an exploded perspective view of the section shown in Fig. 1, Fig. 3 is a plan view of the bearing sleeve 8, Fig. 4 is a side view thereof, and Fig. 5. 6 is a simplified plan view of an embodiment of the present invention, and FIG. 7 is a simplified view taken from the section line - in FIG. 6. The sectional view, FIG. 8, is a plan view of a bearing sleeve 8 based on another embodiment of the present invention. 1... Outer hook, 2... Inner hook, 3... Inner hook rotation prevention member, 8... Bearing tube, 10... Rotating shaft, 2
5... Inner hook contact surface, 26... Anti-rotation contact surface,
27... Outer hook rotation running direction.

Claims (1)

[Claims for Utility Model Registration] A cylindrical shaft joint 7 coaxial with the rotational axis of the inner rotor 1 is provided at the bottom of the outer rotor 1 and protrudes outward. A plurality of screw holes 11, 12, and 13 are formed in the same plane perpendicular to the axis of rotation, and a bearing sleeve 8 is fitted into the shaft coupling 7, and this bearing sleeve 8 is a thin cylindrical screw. It includes a receiving part 17 and circular outward flanges 18 and 19 that are formed at both ends of the axis of the screw receiving part 17 and fit snugly into the shaft coupling 7, and are located at the center of the shaft hole 9 of the bearing sleeve 8. The line 20 is eccentric to the axis 21 of the bearing sleeve 8, and the tip of the rotating shaft 10 of the sewing machine is fitted into this shaft hole 9, and screws 14 to 16 are screwed into the screw holes 11, 12, and 13, respectively. The tips of the screw receivers 17 are brought into contact with the outer circumferential surface of the screw receiver 17, and the screw receiver 17 is deformed and pressed against the rotating shaft 10. When passing between the inner hook contact surface and the detent contact surface that contacts the inner hook contact surface, the inner hook is moved upstream to facilitate the passage of the upper thread. A vertical full-rotation hook characterized by positioning.