The present invention relates to a sewing machines which include automatic needle threading and, more specifically, to apparatus for including in a sewing machine to provide automatic thread taking-up and threading.
Sewing machines including the capability to self-thread the needle thereof are known in the art and greatly appreciated by those using them as they are no longer required to manually insert the thread through the eye of the needle. Such a sewing machine is disclosed in Japan Published Unexamined Patent Application No. S63-89194 which is owned by the common assignee of this application. In that sewing machine, the operation of taking up the tread and threading it through the eye of the needle are simplified over manual threading. Specifically, the sewing machine semi-automatically threads the eye of the needle when an operating member provided at the front face of the sewing machine head is pressed. Since a thread taking-up member is connected to the operating member, the thread taking-up operation can be semi-automatically accomplished, too. In this semi-automated apparatus, however, the threading member, the thread taking-up member, and the operating member are interlocked using a complicated linkage mechanism and cam mechanism. The operator often has to quickly press the operating member with a rather strong force such that the linkage mechanism and the cam mechanism will operate smoothly. Unfortunately, sometimes only an experienced operator can do this successfully. In addition, the designing of the linkage mechanism and the cam mechanism and the adjusting of the interlocking of the various members is difficult and troublesome work.
Wherefore, it is an object of this invention to provide a needle-threading apparatus for a sewing machine with is fully automatic in design and operation.
It is another object of this invention to provide a needle-threading apparatus for a sewing machine which is simple in design.
It is still another object of this invention to provide a needle-threading apparatus for a sewing machine which is easy to operate and which does not require particular strength or skill on the part of an operator.
Other objects and benefits of the invention will become apparent from the detailed description which follows hereinafter when taken in conjunction with the drawing figures which accompany it.