JPS60182994A - Thread cutter 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] [Technical field] The present invention relates to a thread cutting device for a Nikkisen sewing machine.

[Prior Art] Conventionally, in this type of device, in order to adjust the position of the hook that cooperates with the two hooks in accordance with the adjustment of the distance between the two ridges, the hook base was moved against the bed of the sewing machine. A pair of left and right pots are installed so as to be movable along the lower shaft, and each of the hook bases supports a swing shaft parallel to the axis. The upper ends of these swing shafts catch and cut the upper and lower threads [17
Thread cutting blades for cutting are respectively installed movably between an operating position and a non-operating position, and swing arms are respectively installed at the lower ends. Either one of these swinging arms is connected to a single driving source, and between the two swinging arms, the other swinging arm is moved in synchronization with the movement of the one swinging arm being driven. A connecting rod is connected to drive the swinging arm of. Furthermore, this connecting rod has two connecting pieces each having one end rotatably connected to the swing arms and a female threaded portion formed at the other end, and a male threaded portion formed at both ends. consists of a round rod that is screwed into the six female threads of the two connecting pieces, and the length of the connecting rod can be adjusted by rotating the round rod.

In the above-mentioned thread trimming device, the user of the sewing machine
If the hook base is moved due to changing the needle spacing of the book,
As the hook base moves, the two sliding arms connected by the continuous M rod are rotated, and the thread cutting blade is also moved at the same time. Therefore, each time the distance between the two needles changes, the user must adjust the length of the connecting rod and the mounting position of the thread cutter blade, returning the thread cutter blade to its original inactive position. This adjustment work has the drawback of being troublesome and time-consuming.

[Purpose] The present invention was made in order to eliminate the drawbacks of the conventional J.
To provide a thread cutting device for a double nail sewing machine in which the inoperative position of a thread cutting blade does not change.

[Solution] Therefore, in the present invention, the coupling means provided between the thread cutting blade and the single drive device maintains the thread cutting blade in an inoperative position despite movement of the hook base. It is structured as follows.

[Embodiment] The details will be explained below with reference to the drawings showing an embodiment in which the present invention is embodied in a two-needle lockstitch needle feed sewing machine.

In the figure, bellows 1 to 1 of the sewing machine support a lower shaft 3 via bearings 2 and 2', and this upper shaft 3 is connected to and rotated by the upper shaft (not shown). The pot base 4°4' is J5 in Figure 2.
A pair of through holes 41.41' are provided at one end of each pair, and the bearings 2.2' are fitted therein. It is fixed to said bearing 2, 2' by means of a clamping member 6, 6' and a first screw 7, 7'. Also, the other end has a long hole 42.42'
are bored and fixed to the bed 1 by second screws 8.8' through the elongated holes 42, 42'. Therefore, the hook base 4.4' is connected to the head 1.
It is movable along the lower shaft 3 within. This hook base 4.4' supports a pair of hook shafts 91, 91', respectively, which are rotatable around a vertical axis.

As shown in FIG. 1, the lower shaft 3 includes a pair of drive spiral gears r10.1 formed in a line-symmetrical relationship.
0' and their driving spiral gear 10
, 10' are V grooves 40 and 40' formed in the lower shaft 3.
It can be rotated integrally with the lower shaft 3 by the action of screws 11° and 11' protruding therein.

As shown in FIG. 3, a hook 9' is provided at the upper end of the hook shaft 91' supported on the side hook base 4' in FIG. The outer hook 92' of the hook 9' is bobbin 3.
5 is housed in the inner hook 94', and the hook shaft 9
A tip 93' is fixed to the upper end of the needle 1' and captures the needle thread loop formed by the vertical movement of the needle 12'. At the lower end of the hook shaft 91 supported on the hook base 4 on the left in FIG. 2, there is an outer hook 92. A hook 9 having an inner hook 94 and a tip 93 is provided. Further, the pair of hook shafts 91,
Driven spiral gears 14 and 14' formed in a line-symmetrical relationship are respectively fixed to the lower end of the drive spiral gear 91'. They mesh together. Accordingly, the rotation of the lower shaft 3 causes the hooks 9,9' to rotate clockwise and counterclockwise in FIG. 2, respectively.・ Also, an opener 36°36' is installed near the pots 9 and 9'.
is installed.

Incidentally, the pair of left and right hook bases 4.4' are provided with swing wheels 15.1 extending parallel to the pair of hook shafts 91.91'.
5' are respectively supported, and their pivot axes 15.1
As shown in FIG. 2, a pair of thread cutting blades 16.16' formed in a line-symmetrical relationship are fixed to the upper end of the thread cutting blade 5' at the base end via a holder 17.17'. ing. Furthermore, swinging arms 18.18' are fixed to the lower ends of the swinging shafts 15, 15' by screws 19.19', and these swinging arms 18.18' are connected to the thread cutting blade 16. .16'.

Regulation bins 20 and 20' are fixed to the pair of left and right pot bases 4 and 4', respectively.
0.20' limits the swinging range of the swinging arm 18°18'. Furthermore, the coil spring 21.21' is
In FIG. 1, there is a relationship between the left hook base 4 and the left swing arm 18, and between the right hook base 4' and the right swing arm 18'. Normally, the left swing arm 18 is biased counterclockwise (J3), and the right swing arm 18' is biased clockwise.

In the above state, the position of the thread cutting blades 16 and 16' in J5 is set to the inoperative position.

Further, a first connecting plate 23 is pivotally supported at the base end of the left swinging arm 18 by a screw 22.
The connecting plate 23 has a parallel long-hole adjustment hole 24 extending in the longitudinal direction at its tip.

On the other hand, the right swing arm 18' has a base end attached with a screw 22.
' A second connecting plate 25 is pivotally supported by the second connecting plate 25, and the second connecting plate 25 has two third screws 2-6 inserted through the adjustment hole 24 of the first connecting plate 23 at its tip end.
．． The first connecting plate 23 is fixed by 26'.

Further, the right swing arm 18' is provided with a thread cutting cam 30 having a grooved cam 30', a cam engaging body 31 having rollers 31' that can be engaged with the iN cam 30', and a transmission rod 32. A known thread cutting drive source is connected thereto. This knob engaging body 31 is activated by a thread trimming solenoid (not shown) which is activated in response to a thread trimming signal, so that its roller 31'
is fitted with the grooved cam 30'.

By this thread cutting drive source, the right swinging arm 1B' is rotated counterclockwise in FIG. The blades 16,16' are moved into the operative position in which they catch the thread. In this working position the thread cutting blade 16.16'
catches the upper thread and lower thread, and as they move to the inoperative position, cuts the upper thread and lower thread in cooperation with a fixed blade (not shown). The needles 12, 12' are mounted on a copper rod so that their spacing can be adjusted.

Next, its effect will be explained.

In order to change the spacing between two parallel stitches, the user can
First, the spacing between the nails 12, 12' is adjusted, and the position of the hook base 4, 4' on which the hooks 9, 9' are supported is adjusted in accordance with the changed spacing. For this purpose, the user must remove the first screw 7.7', the second screw 8.8' and the third screw 26.2.
6' and screws 11, 11' to make the hook base 4.4' movable along the lower shaft 3.

Next, the user moves the pot bases 4, 4' according to the intervals &112, 12', but the swing arms 1B, 18'
During this period, the swinging arms 18 and 18' are always biased against the regulation bins 20 and 20' (=I), and the swinging arms 18 and 18' do not disengage from the regulation bins 20 and 20' due to this movement. By retightening the screws 7, 7', the second screws 8, 8', the third screw 26.26' and the screw 11.11', the thread cutter connected to the swinging arm 18.18' is removed. Blade 16.
The movement of the hook base 4.4' is completed without any change in the position of the hook 16'.

Incidentally, the present invention is not limited to the above-described embodiment, but can also be embodied in the apparatus shown in FIG. 5 as a further embodiment.

The thread cutting blades 16, 16' are fitted into recesses 45 extending in the cloth feeding direction on the upper surfaces of the hook bases 4, 4', and are slidably supported on the four parts 45. On the other hand, the abbreviated connecting body 50 is installed so as to be able to slide on a shaft 55" supported on the bed 1 so as to extend in the cloth feeding direction, and one end of the shaft 55" is provided with a driving device such as a solenoid. 7
A pin 58 that can be engaged with a long hole 57 formed at the tip of a rocking plate 56 that is rocked by the swing plate 56 is formed at the other end, and a bolt parallel to the moving direction of the pot base 4.4' is formed at the other end. Long hole 5
9 is bored, and the long hole 59 has an engaging pin 60.60 formed at the base end of the thread cutting blade 16.16'.
' is engaged. Here, the oscillating motion of the oscillating plate 56 is converted into a reciprocating movement of the connecting body 50 in the cloth feeding direction by the elongated hole 57, and the thread cutting blades 16, 16' move between the operating position and the non-operating position. Moving. The slot 59 also allows the thread cutting blade 16, 16' to remain in its inoperative position despite the movement of the shuttle base 4.degree. 4'.

[Effects] As described above, the present invention has the advantage that the inoperative position of the thread cutting blade is maintained regardless of the movement of the hook base, and readjustment of the thread cutting blade after the movement of the hook base is unnecessary.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the present invention as a lockstitch nail feed sewing machine, Fig. 2 is a back view thereof, Fig. 3 is a side view showing the hook base, and Fig. 4 is a front view showing an embodiment of the invention. 5 is a perspective view showing another embodiment. In the figure, 1 is the bed of the sewing machine, 4.4' is the hook base, and 9.9
' is the hook, 12.12' is the needle, 16.16' is the thread cutting blade, 18.18' is the swing arm, 20.20' is the regulation bottle, 2
1.21' is a coil spring, 23 is a first connecting plate, 25
is the second connecting plate, and 26.26' is the third screw. Special W [Applicant: Katsuji Kawashima, Chief Director, Brother Industries, Ltd.

Claims (1)

[Claims] 1. Two buttons installed along an axis perpendicular to the cloth feeding direction so that the interval between them can be adjusted, and the two buttons working together to create a J:ri seam. two hook bases, each having a hook to form a sewing machine, and two hook bases that are moved along the axis line with respect to the bed of the sewing machine as the interval between the two nails is adjusted.
Smells like a real needle sewing machine. Two thread cutting blades are installed movably between an inoperative position and an operating position on the two hook bases, and a single thread cutting blade is provided for driving the two thread cutting blades. a driving source; and a connecting means provided between the driving source of the instep and the two thread cutting blades to maintain the thread cutting blade in the inoperative position regardless of movement of the two hook bases; A thread cutting device for sewing machines.