US3572267A - Sequencing devices for ticket tacker sewing machines - Google Patents

Abstract

A SEWING MACHINE HAS BEEN PROVIDED WITH IMPROVED SEQUENCING MEANS FOR SEWING A MATERIAL SUCH AS A GARMENT TAG TO A FABRIC. THE SEWING MACHINE WHICH CONVENTIONALLY HAS MEANS FOR LIFTING A PRESSER FOOT FROM ITS NORMAL DOWN POSITION, MEANS FOR INITIATING A STITCHING CYCLE, MEANS FOR SEWING SAID PREDETERMINED NUMBER OF STITCHES AND MEANS FOR TERMINATING THE STITCHING CYCLE IS MODIFIED WITH A COMBINATION COMPRISING MEANS FOR HOLDING THE PRESSER FOOT IN AN AUTOMATICALLY DISENGAGED UP-POSITIONS, AND MEANS FOR INITIATING A STITCHING CYCLE AND WHICH LAST MEANS COMPRISE (A) MEANS FOR DEACTIVATING THE MEANS FOR HOLDING SAID PRESSER FOOT IN THE UP-POSITION, AND (B) MEANS FOR SEQUENTIALLY INTERLOCKING: A PRESSER FOOT ENGAGING MEANS, WITH THE STITCH SEWING MEANS, WITH THE STITCHING CYCLE TERMINATING MEANS. THE STITCHING CYCLE TERMINATING MEANS INCLUDE MEANS FOR REACTIVATING THE MEANS FOR HOLDING THE PRESSER FOOT IN THE UP-POSITION.

Description

March 23, 1971 A. G. BEAZLEY SEQUENCING DEVICES FOR TICKET TACKER SEWING MACHINES Filed April 1, 1969 Tia l g 28 32 /2 y 9 38 o) o E? I Q Q 37 O 43 Q71: I M 44 43 L f -.23|"' 32 i L J Bu c ==f 4' rlZOv 1 AC 34 E1 M4) WW1} ATTOR YS lzgsmon flubg y .Beuzley United States Patent Oflice US. Cl. 112-67 1 Claim ABSTRACT OF THE DISCLOSURE A sewing machine has been provided with improved sequencing means for sewing a material such as a garment tag to a fabric. The sewing machine which conventionally has means for lifting a presser foot from its normal down position, means for initiating a stitching cycle, means for sewing said predetermined number of stitches and means for terminating the stitching cycle is modified with a combination comprising means for holding the presser foot in an automatically disengaged up-position; and means for initiating a stitching cycle and which last means comprise (a) means for deactivating the means for holding said presser foot in the up-position; and (b) means for sequentially interlocking: a presser foot engaging means; with the stitch sewing means; with the stitching cycle terminating means. The stitching cycle terminating means include means for reactivating the means for holding the presser foot in the up-position.

This invention relates to a cyclically operated sewing machine; more particularly this invention pertains to a pattern cam operated sewing machine stitching a predetermined number of stitches such as at a corner of a tag and wherein the pattern cam controlled operation is modified to eliminate operator fatigue and errors causing machine malfunction.

PRIOR ART Automatic tacking machines are widely known and used in the industry to affix to a garment various identification tags, labels, markings and the like. The sewing machines employed for this purpose are single-thread chain stitch machines having a mechanism for moving the material with the tag from each stitch position to the next in a predetermined pattern and regulating the number of stitches in each discrete stitch pattern. These machines are of the cylinder-bed construction and have a pattern cam disk or wheel mounted on the side of the arm at the hollow standard of the machine. A drive shaft journaled in the standard is provided. On this shaft at the balance wheel end of it, a stop motion device coupled to a clutch is generally employed. The pattern cam is mounted on a short, transverse shaft (to the mainshaft) driven from the main or drive shaft by a worm and a Worm Wheel. Besides the pattern forming cam groove, the pattern cam has other cam surfaces with cam follower mechanisms. These follower mechanisms through various levers and linkages activate mechanisms provided for stopping the machine, nipping the thread below the throat plate, or severing the thread, etc. A representative machine of this type is a Singer 114-31 sewing machine or a sewing machine illustrated in US. Pat. 2,938,477.

In sewing a tag to a garment, each discrete stitch grouping is carried out in an identical sequence. For example, a garment tag is placed on a fabric to which the tag is to be atfixed. The operator raises a presser foot with a left foot pedal activated mechanical device thus overcoming a spring associated with the presser foot which holds the presser foot in its normal down position. Thereafter, the operator lifts the left foot which releases the presser foot and then momentarily depresses another foot pedal with 3,572,267 Patented Mar. 23, 1971 the right foot releasing the pedal as soon as the machine starts to sew. Once the machine is started, it is provided with mechanical clutch latching means which do not release until the end of the stitching cycle. When the machine stops the operator depresses the left foot pedal which lifts the presser foot and removes the workpiece and places it under the needle at another corner of the tag to repeat the sequence.

Although other machines operated at higher speeds are known, in general, these cam controlled sewing machins run at about 1500 rpm. and will have as a representative number 14 stitches for each discrete stitch group which is about .6 second per sewing cycle for each stitch grouping. As can be envisioned, the operator must be well coordinated and very skilled at rapid and precisely timed foot operation and able to time each activation without overlapping the same with another, possibly, destructive operation. Moreover, the continuous operation of a sewing machine with these mechanical controls tires an operator both physically and mentally leading to degradation in quality and output and increasing the statistical incidence of accidents.

DISCLOSE-D SEWING MACHINE It has now been found that if the cyclical sewing machine is provided with a new combination of properly sequenced, interrelated, and interdependent means for carrying out the cyclical operation in place of the prior art means calling for a different interrelationship and interdependence of same and different means, then unobvious results in lessening operator fatigue, improving production, lessening machine wear etc. are observed because of the elimination of steps and improved sequencing achieved with the novel combination. In the accompanying drawings which illustrate a preferred form of this invention:

FIG. 1 is a front perspective view of the sewing machine having this invention applied thereto; and

FIG. 2 represents an electro-pneumatic circuit interrelated with mechanical means which activate the sewing machine in accordance with the invention herein.

In reference to the figures and wherein the same elements are designated by the same numbers, FIG. 1 illustrates the so-called cylinder-bed sewing machine having a frame which includes a free ended work supporting bed 11 which admits tubular articles such as pants. The bed 11 is formed to extend from hollow vertical standard 12 formed with a bracket arm 13 which overlies the bed.

Further, in reference to FIG. 1, the cylinder bed has on the top, work-support surface a feed plate 21, a throat plate 22, and a presser foot 23 or as it is sometimes called an upper jaw of a work clamp, the lower jaw being the feed plate 21. At the end of the bed and adjacent the standard, a forward projecting lever interconnects with other levers (not shown), in the conventional manner, the feed plate 21 and the pattern cam 25 to define via the cam follower mechanism the movement of the feed plate 21 and thus the tag and fabric when appropriately clamped. This movement is necessary to define the stitch pattern.

Overlaying the feed plate levers is the presser foot lever 26 with a projecting finger 27. This finger is in turn engaged by the presser foot lifting bar 28 having a second pin 29 engaging the finger 27. In order to bias the presser foot toward and away from the workpiece, the presser foot is spring held in the clamped position by a spring 30 which is interconnected with the presser foot lever at a pivot (or fulcrum) point 31 with the feed plate lever. The presser foot is lifted or biased via a presser foot bar lifting lever 32. Lever 33 forms part of a cam follower mechanism (which is not shown) and it operates a lower thread nipper (not shown).

A thread breaker bar 34 is interconnected with a conventional thread breaker or cutting mechanism under the throat plate (not shown). The thread breaker bar is activated by a conventional cam follower mechanism (not shown) interconnected with a cam surface on the pattern cam disk 25.

The pattern cam disk 25 is interconnected through a short shaft 36 and a worm gear on the shaft to a worm on the main shaft 37 which is journaled in the frame. The main drive shaft may be provided with a stop motion device either through an appropriately designed device mounted on the shaft capable of stopping the machine by means of the motor driving the shaft with the needle bar and needle in the tip-position or a stop motion device operated from the pattern cam disk 25 by a cam follower mechanism and interconnected to the drive shaft at the balance wheel 38 end thereof. As the stop motion devices are well known in the art, these devices have not been shown.

OPERATION OF THE DISCLOSED SEWING MACHINE Whereas in the prior art devices the cyclical operation starts with the presser foot resting in a clamped relationship on the feed plate, according to the present invention, upon activation of a master switch, the presser foot is lifted by a solenoid valve admitting fluid under pressure to a fluid work device e.g. a pneumatic cylinder 39. Explaining the novel sequencing means used therewith and in reference to FIG. 2, when the sewing machine is in the stop position, i.e. at the beginning of cycle, (or as further explained herein when provided with a training device), all switches and relay 40 are in the position shown in FIG. 2. Upon depressing the foot switch 41, which is a two contact switch, the presser foot solenoid valve 42 is de-energized, the presser foot 23 goes down because it is spring actuated. The presser foot lever 32 in turn activates a microswitch 43 designated as such in FIG. 2 and also identified in FIG. 1 with the same numeral. The employment of a microswitch 43 is a sequencing safeguard which has been found to be useful for preventing the clutch from being actuated unless the presser foot is down. The A section of the foot switch energizes the clutch cylinder solenoid valve 44 which in turn operates a fluid work device, e.g. an air cylinder 45 identified in FIG. 1. This work device mechanically latches by conventional means the sewing machine in a stitching or sewing cycle. The relay 40 is energized by B section of the foot switch and it is latchingly held by its own holding contacts through the ground or return line of thread breaker bar microswitch designated as 46 in FIG. 2. The circuit for switch 46 has also been identified in FIG. 2: and the switch is identified with the same numeral in FIG. 1. This latching action prevents the presser foot solenoid valve from being energized when the operator releases the foot switch before the machine has finished its sewing cycle governed by the pattern cam thereafter. Before the machine finishes its complete cycle forming the discrete stitch grouping, but after it has finished its 14 stitch cycle, the needle and bobbin threads are automatically trimmed by the thread trimmer (not shown) which is activated by the thread breaker bar 34. As previously explained, the thread breaker bar is activated by a cam follower mechanism from the pattern cam disk. The thread breaker bar 34 makes a lateral oscillation during the thread trimming operation. Consequently, this mechanical feature has been used to trigger the switch 46 by means of pin 35 on the bar. The momentary back and forth movement of the bar de-energizes the relay 40 which in turn causes the presser foot to lift and end the cycle, i.e. allows the next discrete stitch group to be formed immediately.

An additional aspect of this invention is an aid in training new operators. This aspect of the invention is illustrated in FIG. 2 wherein the foot switch 41 has been provided with a two stage, interruptible switch. The dotted portion of the diagram illustrates this feature which operates as follows. A foot switch is provided with a first stage, i.e. the dotted-section and a second stage consisting of A and B. If the operator presses down for a partial foot switch travel, only the first stage switch is actuated.

This stage controls lowering and lifting of the presser foot independently of the other means to initiate and control the sequencing of the stitching operation. To check workpiece positioning, an unskilled operator can lower the presser foot before starting sewing. If the operator wishes to lift the presser foot, it allows the spring operated foot pedal to return and energize presser foot solenoid valve 42. However, if the operator is satisfied that the workpiece is properly positioned, pressing down harder starts the machine through the engagement of A and B parts of the switch.

After a short training period, the operator no longer needs to make use of this feature and presses hard enough to actuate only the A and B parts of the switch with the first stage being eliminated, or if it is desired by retaining the first stage and pressing down to actuate both first and second switches in one motion.

What is claimed is:

1. A control system for a sewing machine comprising a first solenoid for controlling a presser foot, said solenoid being normally energized when in a first position for maintaining said presser foot in an open position;

actuation means connected to a thread cutting mechanism;

a second solenoid for initiating and maintaining a stitching cycle which includes operation of the thread cutting mechanism near the end of the cycle;

a two position latching relay for energizing said first solenoid when in said first position;

a manually operated switch for operating said relay to latch it in a second position thereby de-energizing said first solenoid and closing the presser foot, and for energizing said second solenoid whereby initiating and maintaining the stitching cycle;

a first electrical switching means connected in series between said manually operated switch and said second solenoid, said first switch means being operated by said presser foot for providing a closed circuit between said manually operated switch and said second solenoid when said presser foot is in the down position; and

a second electrical switching means connected to said latching relay for returning said latching relay to its first position, said second switching means, being activated by said actuation means upon operation of the thread cutting mechanism at the end of the sewing cycle.

References Cited UNITED STATES PATENTS 2,764,112 9/1956 Happe 112-67 2,928,362 3/1960 Benink et a1. 112-67 3,157,261 11/1964 Bono ll267X 3,245,369 4/1966 Myska 112-67 3,298,341 1/1967 BOnis l12219 H. HAMPTON HUNTER, Primary Examiner

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