JPS6214153Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for clamping thread ends in an embroidery sewing machine.

In conventional embroidery sewing machines, a single head is equipped with a plurality of needles, and threads of different colors are passed through the needle holes with their ends slightly protruding from the needle holes, and are held in standby as stop threads. Embroidery is efficiently performed using desired colored threads. However, it is assumed that the end of the thread of the required length has been let out from the needle hole and is in a stopped state.
Although the next embroidery is ready for immediate embroidery, the end of the thread often slips out of the needle hole during the next sewing process. To prevent this, the end of the thread that protrudes from the needle hole is made longer and wrapped around other objects. Therefore, the yarn end length is longer than necessary, which makes the thread uneconomical, and it is necessary to cut off the extra thread end with scissors after embroidery.

In view of this drawback, the present invention is designed to ensure that the end of the thread of a predetermined length that protrudes from the needle hole is securely held while waiting for the next embroidery.

The present invention will be explained below based on the illustrated embodiments.

In the figure, reference numeral 1 denotes a head body of an embroidery sewing machine, and a plurality of needle bars 3 are arranged and provided directly at the bottom of the head body 1 or on a needle bar mounting plate 2 provided at the bottom of the head body. The large number of needle bars 3 are arranged in a straight line in the illustrated embodiment, but they may also be arranged in a disk shape, and in FIG. Fig. 4 shows the arrangement arranged in a circular arc shape. A needle 4 is attached to the lower end of each needle bar 3 in a replaceable manner, and a pair of presser feet 5 are also provided, and any one of the needle bars can be selectively moved up and down. There is. In the case of a disk-shaped needle bar mounting plate, the needle bar mounting plate can be rotated to the right or left relative to the main body 1, and if the head main body is straight, the head main body can be slid laterally to select the desired needle bar. The needle bar is moved up and down to perform embroidery using the operating thread.

Further, a bracket 6 is vertically provided at the lower part of the head body or the lower part of the needle bar mounting plate in accordance with the shape of the plate, that is, in a straight line if the needle bar mounting plate is straight, or in an arc shape if the needle bar mounting plate is arcuate. A plurality of thread end clamping devices 7 are provided on this bracket 6, one facing each needle bar. The thread end clamping devices 7, 7, . . . are provided along the shape of the bottom piece of the needle bar mounting plate and in accordance with the needle bar spacing. This yarn end clamping device 7 has two spherical plates 7a, 7a made of metal or synthetic resin formed into convex lens-like spherical shapes so that their central bulges touch each other, and a bracket bottom piece 6a at the center. A spring 7c is provided so as to pass through the fixed shaft 7b and press the upper spherical plate 7a against the lower spherical plate with a pressing force suitable for holding the yarn end. This spring 7c is provided between the upper end of the shaft 7b and the upper spherical plate. Further, as a different embodiment of this yarn end clamping device 7, there is a fifth embodiment.
As shown in the figure, a receiving piece 6b is provided at the bottom of the bracket 6 approximately horizontally or slightly inclined, and a presser 8 is placed above the receiving piece 6b facing the receiving piece. It is also possible to adopt a structure in which the presser 8 is supported by a guide 9 provided at the support piece 6b and is pressed by a spring 8a with a desired pressing force against the receiving piece 6b.

Furthermore, embroidery thread may become fluffy with cotton thread, and as a result, the end of the thread may wrap around the outer periphery of the sewing machine needle, making it impossible to perform the desired embroidery. A yarn end clamping device as shown in FIG. 6 is suitable for such yarns that tend to cling to the needles. A hole or recess 6c is formed in the bottom piece 6a of the bracket 6, and a presser 10 is disposed above the hole or recess. A spring 12 is applied to one end of the upper piece 10a, whereby the lower part of the presser 10 is pressed against the bottom piece, and the protrusion 1 provided at the lower part of the presser
0b is fitted into the hole or recess 6c of the bottom piece, the thread end is held between the lower part of the presser and the bottom piece, and the thread is bent and held between the hole or recess and the protrusion, and the thread end is This device clamps the thread by forming a bend. In order to release the clamping of the thread, the upper part of the presser foot is pressed against the spring 12 when the thread end hooking tool, which will be described later, moves forward. Swing the tool to separate the lower part of the presser from the bottom piece,
The presser is released by pressing it with a solenoid, roller, or the like.

The opening and closing operations of the support end clamping device shown in FIGS. 3 and 5 are performed by inserting and removing a thread end hook 13 provided at the lower part of the main body at a position rearward from the needle bar. This thread end hooking device 13 is provided at the lower part of the head body 1 so that the lower part of the needle tip extends toward the needle bar side by a driving source such as an air cylinder, a cam, a wire, a solenoid link device, etc. . At this time, the tip of the thread end hook is inserted between two spaced open spherical plates or between the presser and the bottom piece and projects below the needle tip to the needle thread position, and the thread end is held in the hook shape at the tip. When the hook 13a is hooked and moved backward, the projecting range is determined so that when the hook 13 is moved backward, it will be located slightly behind the space between the two spherical plates or between the receiver and the presser, and when the hook 13 moves forward in the projecting direction. The upper spherical plate or presser is pushed up against the spring by the hook, and as a result, the spherical plate or the presser is automatically moved up and away from the lower spherical plate or receiver against the spring. The hooking tool 13 enters between the two separated parts, and when the end of the thread is hooked and the thread is moved back to its original position, the upper spherical plate presses against the lower spherical plate or the presser presses against the bottom piece again. Then, the end of the thread that has been hooked is held by the hook-like hook portion. The yarn end hooking device may be of a rotating type using a rotary solenoid or the like, so that the yarn end hooked on the hook portion can be held by a yarn end clamping device.

According to the present invention, the end of the stop thread threaded through the waiting needle is held close to the needle tip by a spherical plate or bottom piece pressed by a spring and a presser. Since each thread is held in a pinched state, the end of each stop thread does not unnecessarily slip out of the needle hole, and when the thread end hook is operated by a solenoid, air cylinder, cam, link mechanism, etc., the thread end clamping device opens and closes automatically, and when embroidery is performed with reliable clamping and appropriate clamping force, only the operating thread will naturally come out of the clamping device, and the other stopped threads will remain clamped. This allows for reliable embroidery.

[Brief explanation of drawings]

Figure 1 is a front view of the main parts, Figure 2 is a plan view, and Figure 3 is a front view of the main parts.
The figure is a perspective view, and FIGS. 4, 5, and 6 are views of different embodiments. 1...Main body, 2...Needle bar mounting plate, 3...Needle bar,
4... Needle, 5... Presser foot, 6... Bracket, 6
a... Bottom piece, 7... Yarn end clamping device, 7a... Spherical plate, 7b... Shaft, 7c... Spring, 8... Presser,
9... Guide, 10... Presser, 11... Shaft, 1
2... Spring, 13... Yarn end hook, 13a... Hook portion.

Claims (1)

[Scope of utility model registration request] A bracket is provided vertically below the head main body, which is equipped with a plurality of needles so as to be able to be used selectively, and further behind the needle bar, and a plurality of needles facing the bracket are connected at the bottom of the bracket. A thread end clamping device is disposed on the top of the bottom piece, facing each needle bar, and a thread end clamping device is provided on the top of the bottom piece, and the thread end clamping device is installed on the bottom piece of the bracket in a spring-pressed state to allow the thread end hook to pass when it moves forward, and to clamp the thread end that has passed through the needle hole, and at the position where the sewing machine embroidery is finished and the thread has been let out for the required length from the needle hole. A thread end clamping device for an embroidery sewing machine, comprising a thread end hook for clamping the cut thread end at a position rearward of the thread end clamping device.