Title of Invention

"MULTIPORPOSE ZIG ZAG STICHING MACHINE"

Abstract

A raultipurpose machine is a zig zag stitching machine. Zig zag movement is achieved with a needle bar holder. Needle bar holder moves with the aid of a cam having §0° acending and 90° decending contour. In one complete revolution of handwheel the needle penetrates the cloth two times. A knob is provided on the NVZPC shaft to vary the zig zag width. Stitch length is controlled by the adjustable knob connected with feed regulator. The zig zag movement starts from the centre position of the needle and traverses equal distance on either side from the centre point, as show in Figure A.

Full Text

The present invention relates to a multipurpose Zig Zag stitching machine. In the past Zig Zag stitching machines have employed a radial grooved bracket consisting of numerous parts positioned within a N.V. Bracket slide. A disc is provided within the N.V bracket slide. A block is guided between the two walls of the grooved bracket. This block moves in a linear direction while the machine is in operation. The linear motion is transferred to the needle bar holder. This mechanism is being employed in the 298 type of stitching machines of the Applicants. The stitching machines of the prior art for effecting the Zig Zag movement involved a number of components was heavy and very complicated besides being expensive. Due to the irregular shape of the disc, the motion of the sewing machine was not smooth and lighter. Therefore there was need for a simpler but improved, cost effective and efficient machine for effecting Zig Zag stitching and also ensuring smoother and lighter motion. It is an objective of the present invention to achieve Zig Zag movement of the needle by different and improved mechanism. It is a further objective of the invention to design a cam and arrange it with adjacent components in a manner that it gives simple harmonic motion which helps the machine to run smoother and lighter. A Zig Zag machine has one main driving shaft usually called as arm shaft. The arm shaft on rotation provides motion through separate mechanisms required for stitching operation. There are three mechanisms involved in stitching, the Needle Bar mechanism, the Feed dog mechanism, and the the Zig Zag mechanism. The needle bar mechanism and the feed dog mechanism are conventional as found on any Zig Zag machine and in straight stitch machines respectively. SUMMARY OF THE INVENTION The invention provides an improved Zig Zag mechanism for a stitching machine achieved through a set of gear and lever mechanism. A helical gear fixed on the arm shaft transmits motion to the NV gear with inbuilt cam. The cam actuates a lever which in turn sets into motion the Zig Zag bracket and a slide block. The slide block pushed needle bar holder through a rigid link bar. Thus the circular motion through the helical gear of the arm shaft is converted into oscillatory motion of needle bar. The width of the Zig Zag movement is varied by adjusting the initial position of the slide block. The initial position is preset with the help of needle vibration zero position shaft fitted with a knob. This knob is accessible to the operator for presetting of the Zig Zag width. In accordance with the present invention there is provided a multi purpose Zig Zag stitching machine comprising an arm shaft rotating in circular motion, an oscillating rock shaft being connected to the said arm shaft, said oscillating rock shaft having means for connecting it to a shuttle body and a feed dog to enable the feed dog to move up and down, a feed fork having a forked end associated with the said arm shaft by means allowing it to rotate, means for up and down movement of the feed fork, means located in the feed fork providing linear motion to the feed dog, said arm shaft being associated with needle bar crank means having located therein needle bar which moves up and down, said needle bar having clamped thereon a stitching needle, a rigid bracket affixed to the main body of the machine comprising a helical gear affixed to the arm shaft, said helical gear transferring the motion to another gear with an inbuilt cam, the said cam being in contact with a lever which is associated with a Zig Zag bracket and a slide block setting them into motion, said slide block having means for moving to and fro the needle bar thereby making it to oscillate the needle in a Zig Zag manner. Accordingly: the present invention relates to a multi purpose Zig Zag stitching machine comprising an arm shaft (1) rotating in circular motion, an oscillating rock shaft (3) connected to the said arm shaft, said oscillating rock shaft (3) having means for connecting it to a shuttle body (11) and a feed dog (26) enabling the feed dog to move in up and down direction, a feed fork (20) having a forked end associated with the said arm shaft (1) enabling it to rotate, means provided with said feeding for providing up and down movement of the feed fork (20) , means located in the feed fork (20) providing linear motion to the feed dog, said arm shaft (1) associated with needle bar (30) crank, enabling the needle bar move up and down, said needle bar having clamped thereon a stitching needle, a rigid bracket affixed to the main body of the machine having a helical gear (60) affixed to the arm shaft (1) , transferring the motion to another gear having a cam, the said cam being in contact with a lever (44) associated with a Zig Zag bracket and a slide block setting them into motion, said slide block having means for moving to and fro the needle bar thereby making it to oscillate the needle in a Zig Zag manner. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS: Fig. 1 is a perspective view of multipurpose Zig Zag machine. Fig. 2 is an isometric view of the drive system to the shuttle driver. Fig. 3 is an isometric view of the drive system to the feed dog. Fig. 4 is an isometric view of the drive system to the needle bar. Fig. 5. 6 and 7 illustrate the Zig Zag system. PREFERRED EMBODIMENTS OF THE INVENTION The invention and the working of the machine will now be described with reference to the accompanying drawings. Figure 2 illustrates the machine wherein the main shaft on (arm shaft) (1) is rotating in circular motion. A CC rod (2) is fitted on the arm shaft and it gives oscillating motion to the oscillating rock shaft (3) having two projected wings and one cam. The oscillating rock shaft (3) further transmits motion to oscillating shaft (7) and feed lifting rock shaft (6) . The oscillating shaft in turn gives motion to the shuttle driver (10) and shuttle body (11) through a set of segment and bevel gears (9) . The feed lifting rock shaft (6) controls the up and down motion of feed dog. The amount of up and down motion is fixed and cannot be increased or decreased. Similarly the angle of oscillating of shuttle drive is also fixed. Figure 2 of the accompanying drawings illustrates feed fork (20) having a fork at upper end which is guided through a feed cam (27). The fork end oscillates due to rotation of the cam. Below the fork, a block (22) has been fitted, and guided in the adjustable bracket (21) called the feed regulator. The inclination of feed regulator determines the up and down motion of feed fork (20) . Lower end of the form is joined with feed rock shaft (24) through a crank (23). Feed rock shaft (24) oscillates due to up and down motion to' feed fork (20) .Oscillating motion further gives linear motion to feed dog (26) via hinged member feed bar (25) . The amount of linear motion and direction of feed can be controlled by feed regulator (21) . Adjustment can be done between reverse feed to zero and to forward feed maximum upto (24) stitches per inch of cloth. As illustrated above in figures 2 and 3 the feed dog (26) works under two motion that is linear motion and up and down motion thereby enabling the cloth to move forward. The motion of arm shaft is also transmitted to needle bars through needle bar crank (30). This is illustrated in figure 4. The needle bar crank (30) is further connected to thread takeup crank. The thread takeup crank (35) gives motion to two members, one is thread takeup lever (36) and other is needle bar connecting link (31). Needle bar connecting link is further fitted to the needle bar thorough universal joint. It gives motion to the needle bar which moves up and down. A stitching needle is clamped with the needle bar. The Zig Zag mechanism has been explicitly illustrated in figures 5 to 7. The Zig Zag mechanism is fixed on a rigid bracket (40) which is further fixed on the main body of machine. A cam (62) combined with gear (41) revolve around the pivot pin (42) by means of an arm shaft helical gear (60) fixed on the arm shaft (1) . The cam is eccentric in shape and transfers the motion to the cam follower lever (44) which actuates the Zig Zag bracket through adjustable screw (43) . The Zig Zag bracket (57) pushes the needle bar (52) through slide block (46) and needle vibration connector (56) . One end of spring (53) is fixed with needle bar Holder pin (55) and the other end is fixed with main body with the screw (61) . Needle bar holder (52) vibrates to and fro with the pull and push action of spring & cam respectively. Needle Vibrator Zero Position Controller lever is also hinged on the screw fitted in main bracket (40) . The middle pin of Needle Vibrator Zero Position Controller lever (47) is guided in the fork of Needle Vibrator Zero Position Controller shaft (51) . The side pin of the lever (47) is guided in the slide block (46) . The Needle Vibrator Zero Position Controller shaft (51) is guided in the main body and secured with friction washer (49) and locking nut (48) . A knob (50) is fixed with shaft (51) . As the knob (50) rotates clockwise, the fork of the lever (51) also move in the same direction. As a result, slide block comes downward and away from the fulcrum point of Zig Zag bracket resulting in greater stitch width. When the knob rotates anti-clockwise the slide block goes up and stitch width decreases. But when the slide block crosses the fulcrum of Zig Zag bracket, the adjustable screw (43) breaks contact with Zig Zag bracket. Therefore needle bar holder does not vibrate and stitch is absolutely straight. To control the maximum width stitch, an adjustable stopper (58) is provided on the bracket slide. WE CLAIM;- 1. A multi purpose Zig Zag stitching machine comprising an arm shaft (1) rotating in circular motion, an oscillating rock shaft (3) connected to the said arm shaft, said oscillating rock shaft (3) having means for connecting it to a shuttle body (11) and a feed dog (26) enabling the feed dog to move in up and down direction, a feed fork (20) having a forked end associated with the said arm shaft (1) enabling it to rotate, means provided with said feeding for providing up and down movement of the feed fork (20), means located in the feed fork (20) providing linear motion to the feed dog, said arm shaft (1) associated with needle bar (30) crank, enabling the needle bar move up and down, said needle bar having clamped thereon a stitching needle, a rigid bracket affixed to the main body of the machine having a helical gear (60) affixed to the arm shaft (1), transferring the motion to another gear having a cam, the said cam being in contact with a lever (44) associated with a Zig Zag bracket and a slide block setting them into motion, said slide block having means for moving to and fro the needle bar thereby making it to oscillate the needle in a Zig Zag manner. 2. A machine as claimed in claim 1 wherein the means for connecting the said oscillating rock shaft (3) to the said shuttle body comprises an oscillating shaft (7) and a shuttle driver receiving the motion from the oscillating shaft. 3. A machine as claimed in claim 2 wherein a set of segments and bevel gears (9) are provided between the said oscillating shaft and the shuttle driver. 4. A machine as claimed in claim 1 wherein the means for connecting the oscillating rock shaft (3) to the feed dog (26) comprises a feed lifting rock shaft (6) controlling the up and down movement of the feed dog (26). 5. A machine as claimed in claim 1 wherein the means for oscillating the feed fork (20) is provided with a feed cam (27) rotating in conforming the motion of the arm shaft (1) . 6. A machine as claimed in claim 5 wherein the feed fork (20) is provided with a block positioned (22) in an adjustable bracket (21) , the inclination of the latter causing the up and down movement of the feed fork (20). 7. A machine as claimed in claim 1 wherein the said means for causing the linear motion of the feed dog (26) is a feed rock shaft (24) positioned at the lower end of the said fork and connected to the feed fork (20) by means of a feed crank (23) , causing the up and down movement of the feed fork (20) , oscillating the feed rock shaft and in turn causing linear motion of the feed dog (26) . 8. A machine as claimed in claim 1 wherein the said needle bar (50) connecting link is fitted to the needle bar. 9. A machine as claimed in claim 1 wherein the said cam is inbuilt with the gear and is eccentrically shaped and revolves around a pivot pin (42) by means of the said helical gear (60). 10. A machine as claimed in claim 1 wherein the said lever is a cam follower lever associated with the rotating cam, said lever on contacting the said zig zag bracket actuating it. 11. A machine as claimed in claim 10, wherein a adjustable screw moves the Zig Zag bracket. 12. A machine as claimed in claim 12 wherein the zig zag bracket is provided with an adjustable stopper inverted inwards to control maximum width stitch. 13. A machine as claimed in claim 1 wherein there is provided a needle vibration zero position controller hinged in the said main bracket and having means for moving the said slide block. 14. A machine as claimed in claim 16 wherein said needle vibration zero position controller is provided with a lever and a forked shaft, the said lever having a side pin and a middle pin, the middle pin of the said lever being guided in the fork of the shaft, the side pin of the lever being guided in the said slide block. 15. A multi propose Zig Zag stitching machine substantially as herein described with reference to the accompanying drawings.

Documents:

1283-del-1994-abstract.pdf

1283-del-1994-claims.pdf

1283-del-1994-correspondence-others.pdf

1283-del-1994-correspondence-po.pdf

1283-del-1994-description (complete).pdf

1283-del-1994-description (provisional).pdf

1283-del-1994-drawings.pdf

1283-del-1994-form-1.pdf

1283-del-1994-form-2.pdf

1283-del-1994-form-4.pdf

1283-del-1994-form-5.pdf

1283-del-1994-form-6.pdf

1283-del-1994-form-9.pdf

1283-del-1994-gpa.pdf

abstract.jpg