GB2173440A - Constant speed filament feed in a zipper forming machine - Google Patents

Abstract

An automatic constant rate rotary filament feeding device for a zipper forming machine comprising a stationary mandrel (40) mounted at the center of a rotary table (20), a pair of double pitch filament setting screws (43) and a constant rate rotary feeder (311, 312) mounted on the table (20) so that it rotates around the mandrel (40) with the rotary table, and also rotates about its own axis at a speed proportional to the rotational speed of the rotary table, in a fixed ratio, effected by gears (41, 32), whereby monofilament (51) is fed from bobbin (50) and wound around the mandrel, through the guidance of helical raising upward surface (40) of the mandrel, onto the forming core member (42) to form a helical-shaped filament coil, whose coils are set and formed at high speed by a pair of double pitch setting screws (43) and a surrounding forming mold. Therefore, the pitch of zipper teeth can be accurately made and the productivity can thus be greatly promoted. <IMAGE>

Description

SPECIFICATION Automatic constant rate rotary feeding device for zipper forming machine The present invention relates to a rotary feeding device for zipper forming machine, and more particularly to an automatical constant rate rotary feeding device for zipper forming machine wherein a rotary feeding device is mounted on a rotary table of a zipper forming machine and can be rotated with the rotary table and self-revolving in proportion to the rotation speed of rotary table, and mono-filament is wound and fed by the device and through the guidance of a forming mandrel and screws, whereby it is wound into a helixshaped filament coil, then the filament coil is formed into a continuous zipper coil by a pair of double pitch setting screws of the invention, and its incorporated forming mould at high speed.In this way, the pitch of zipper teeth can be made very accurate, zipper teeth very uniform and possesses proper zipper elasticity.

As well-known in the art, the accuracy of zipper forming pitch of a zipper forming machine depends upon if mono-filament feeding process from filament bobbin to a forming cores member is at a constant rate, that is to say, a constant material feeding rate can produce a zipper coil with accurate pitch. Because mono-filament and bobbin are both rotating during the operation of a zipper forming machine, thus, accuracy of the center axis of the bobbin, the quantity and winding condition of mono-filament wound on the bobbin, and the stability of bobbin mounted on rotary mechanism, are influential factors of the feeding stability of a zipper forming machine.

In conventional zipper forming machine, such as shown in Fig. 6, the bobbin 31 of monofilament, which rotates with the rotary table 32, is placed at a location on periphery of the rotary table 32 with larger diameter in a forming machine. Mono-filament drawing out from bobbin 31 is wound around a forming core member 36 on a up and down reciprocated moving push rod 35 and becomes into helixshaped filament coil. A pair of single pitch setting screws and a forming mould 33 is mounted at upper position of the core member 36, then are used to form a filament coil into a continuous zipper coil meanwhile to feed the zipper coil upward around forming core member and to set the zipper coil into a proper configuration as desired.The defects of conventional zipper forming machine comes from that the bobbin is placed at a eccentric location, under this unbalanced condition when rotary table is rotated, centrifugal force from bobbin 31 will create vibration, therefore, a counter weight 34 must be placed at a proper location of the rotary table to balance out the deficiency. But during zipper forming processing, mono-filament on bobbin will be gradually consumed out, therefore, original balance condition is thence destroyed and certain extend vibration will comes on the rotaty table again.

This vibration not only decreases production rate of zipper forming machine but also causes forming pitch of zipper becoming inaccurate and troublesome reworking of sewing machine. Furthermore, because monofilament, which draws out from the bobbin to form zipper coil, is influenced by rotational centrifugal force, gradual filament length reduction of filament wound on the bobbin, variation of tightness of the bobbin installed on rotary table, inaccuracy of the bobbin center, and uniformity of filament wound on the bobbin, therefore, the tension of filament drawing out from the bobbin changes with the combination of the above mentioned factors, and this in turn causes inaccurate pitch of zipper teeth, thread and needle breaking or difficulty in zipper coil sewing operation etc defects.That is the reason why the production speed of a conventional zipper forming machine can not be promoted.

In addition, zipper coil, which is wound on forming core member, is continuously pushed upward by a pair of setting screws, when screws are forming and pushing the helical zipper coil upwardly, rotary friction will be generated between the setting screw and the forming mould which encompasses the setting screws, if the rotation speed of screws in the forming mould becomes too high, then the setting screws and the forming mould will be worn out quickly. Therefore, this is another reason why the production speed of the conventional zipper forming machine can not be promoted.

Furthermore, the upward feeding motion of mono-filament zipper coil is achieved by the small amount up and down movement of push rod 35, i,e, if mono-filament winds on push rod 35 six hundred times per minute, then push rod must move up and down six hundred times per minute to make both to be matched, therefore, the vibration of rotary table will become comparatively large, and loud noise will thence be generated too in addition to the frequency of up and down motion for driving push rod will be comparatively increased, these are infuential factors of the stability of rotary table, if the speed of a conventional zipper forming machine is further increased, serious wear-out of components will be produced. This is another reason why the rotational speed of the conventional zipper forming machine can not be promoted.

Although the rotational speed of rotary table of the conventional zipper forming machine can be increased to 5,000 rpm or over when bearings are provided on its rotating portion, but there are still comparatively large nonbearing surface to surface rotational friction (with respect to relative area) existed between the zipper setting screws and the forming mould, when the rotational speed of rotary table exceeds 2,500 rpm, even the setting screws and the forming mould are made of worn resisting hard steel, they still can not last longer under this condition, thus the rotational speed of the conventional zipper forming machine can not be promoted as it is the technological bottle neck to be brokenthrough.

The principal object of the invention is to overcome the existing defects of the conventional zipper forming machine and to make a technological break-through of the bottle neck of the conventional zipper forming machine, and to provide a high speed automatic constant rate rotary feeding device, by which, mono-filament for zipper forming is wound around a rotary feeder on rotary table, and unilized the rotational force of the rotary feeder to draw out mono-filament and feeds mono-filament to forming mandrel of zipper forming machine at constant feeding rate.According to the present invention, during operation, the feeding rate of mono-filament is not affected by centrifugal force which is generated by the rotation of mono-filament bobbin to draw out mono-filament, nor the centering accuracy of the bobbin, neither the remaining quantity of mono-filament which is wound on the bobbin, thus, all above mentioned defects relevant to feeding mono-filament are completely eliminated and a controlled automatic constant rate material feeding feature is built in, consequently, the pitch of formed zipper coil or zipper teeth becomes very accurate and uniform respectively as well as zipper possesses very good elasticity, therefore, good quality zipper can be produced, forming speed of zipper forming machine can be greately increased, and productivity can be promoted as a consequence.

Another object of the invention is to provide a mono-filament automatic constant rate of feeding device wherein the rotational speed of the rotary material feeder of the invention can automatically adjust material feeding rate in accordance with the rotationed speed of the rotary table, which maintains the tension of mono-filament to a proper uniform level, therefore no matter what ratational speed of the zipper forming machine is utilized, fast revolving or slow revolving, a uniform zipper pitch and an excellent zipper elasticity can be maintained.

A further object of the invention is to provide a mono-filament automatic constant rate feeding device in combination with a stationary forming mandrel means having a helical oblique raising surfaces at the top for zipper forming machine which eliminates the conventional cams, connecting rod, and moving fixing seats and their driving power as they are required to make conventional push rod up and down movement, which not only simplifies the structure of zipper forming machine, reduces parts wear-out and troublesome, but also greately lowers its noise down to a minimum level, contributes a large extent to its operation stability, and makes the operating speed of zipper forming machine to be greately increased becoming possible.

Still a further object of the invention is to provide a mono-filament automatic constant rate feeding device in combination with a double pitch setting screws and a stationary mandrel means for zipper forming machine wherein due to the mutual contributions of double pitch setting screws, mandrel means, and constant material feeder, the rotational speed of zipper forming machine in accordance with the invention can be readily increased to 3,600 rpm, meanwhile the forming speed of setting screws can be reduced from 2,000 rpm to 1,800 rpm, however, the productivity of the zipper forming machine is promoted 1.8 times higher than before; that is to say, the production rate of the invention is promoted from 200 yards to 360 yards per hour.

An additional object of the invention is to provide a mono-filament automatic constant rate feeding device in combination with a double pitch setting screws and a stationary forming mandrel means for zipper forming machine by which, the pitch of zipper is very accurate, and zipper teeth is uniform and even, consequently, the post reworking of zipper teeth sewing becomes very convenient without thread and sewing needle being broken, which in turn makes productivity of post reworking to be greately promoted, and wastes reduce to lest extent, thence, the preworking and post-reworking cost can be greately reduced.

Other objects and advantages of the invention will become apparent during the following description of the accompanying drawings, wherein: Figure 1 is a partially cross-sectional view of an embodiment of the invention which is mounted on a zipper forming machine; Figure 2 is a partially cross-sectional view of the invention; Figure 3 is a perspective view of Fig. 2; Figure 4 is an enlarged side view of a double pitch screw of the invention; Figure 5A is a front view of a stationary forming mandrel of the invention; Figure 5B is a left side view of Fig. 5A; Figure 5C is a right side view of Fig. 5A; Figure 6 is a front view of a rotary table of a conventional zipper forming machine.

As shown in Fig. 1, the mono-filament automatic constant rate feeding device of the invention comprises a rotary material feeder 30 mounted on rotary table 20 of the rotary filament winding mechanism of the zipper forming machine 10, which rotates with rotary table 20, a stationary forming mandrel 40 provided at center of the table 20, which has a helical oblique raising surface at the top, and a pair of setting screws with double pitch threads. Rotary feeder 30 as shown in Figs. 2 to 3 includes a driven gear 32 which engages with a gear portion 41 provided at center part of said mandrel 40, a gear shaft 31 which is fixed on the center of the gear 32, and a Ushaped bracket 35 which is fixed on the rotary table for supporting gear shaft 31.

As shown in Fig. 2, at the upper part of gear shaft 31, there are an oblique conical surface 3.11, a slipless feeding axis 312, and a stop ring 314. The upper part of the gear shaft 31 is supported on the U-shaped bracket 35 by a bearing 34, the lower part 313 of the gear shaft 31 is inserted into a bearing 331 which is fixed in a bearing seat 33 of rotary table. Because the gear 32 is engaged with the center part gear portion 41 of the stationary mandrel 40 (without revolving), therefore, when the rotary feeder 30 is rotated with the rotary table, gear 32 will be revolving around the stationary forming mandrel 40, which causes the rotary material feeding axis to be ratated as a consequence.

As shown in Fig. 1, a bobbin 50 is located under the rotary table 20 and rotates with a rotary stand 55 which is synchronously rotating with the rotary table 20. Mono-filament coming out from the bobbin 50, should first pass through tension adjuster 551 on rotary stand 55, then pass through guide hole 201 and tension adjuster 21 on the rotary table 20, then wind on the oblique conical surface 311 and guide to slipless axis 312, from slipless axis 312 mono-filament is thence fractionally wound out and through the guidance of helical oblique raising surface at the top of the stationary mandrel 40, the mono-filament is fed to the periphery of forming core member 42 to be wound into helical-shaped zipper coil, then a pair of double pitch screws 43-43 (see Fig. 2 and 4) are used to form and set the helical coil into continuous zipper coil and feeds it upwardly along the forming core member 42 and screws 43-43.

The oblique helical raising surface of forming mandrel 40 of the invention will be explained by reference to Fig. 5A to 5C. from these figures it can be seen the forming mandrel 40 of the present invention consists of a front and a rear half conical bodies 40A and 40B, but the height of tip part of front conical body 40A is higher than that of rear half conical body 40B, also the slope of the right side 401 of the front half conical body 40A is steeper than that of the left side 402, and the slope of the right side 403 of the rear half conical body 40B is steeper than that of the left side 404 too, because of these differences, a helical oblique raising surface 400 is formed on tip part of the forming mandrel 40 (see Fig. 5A and 5B). When mono-filament is wound on this surface, through the inertia action of mono-filament and the raising action of helical oblique raising surface, the mono-filament wound coil will naturally from stationary forming mandrel raise to tip part thereof and then to the periphery of forming core member 42, in this way, the later filament coil pushes the former filament coil upward through the cooperation of the core member 42 and the pair of screws 43-43, the formed zipper coil will thus be pushed out continuously as predetermined.

During operation, the rotary table 20 is driven by a driven shaft 11 and the rotary feeder 30 revolves with the rotary table 20, because driven gear 32 is engaged with the middle gear portion 41 of stationary forming mandrel 40, it revoles at a fixed ratio with the rotational speed of the rotary table 20, which is turn causes the rotary feeder 30 to draw out mono-filament 51 from bobbin 50, then through the helical oblique raising surface 400 of stationary forming mandrel 40 feeds it around the periphery of forming core member 42 at a constant rate for winding up into helical coil, thereafter, the helical coil is speedly formed into continuous zipper coil and pushed up along forming core member 42 by a pair of double pitch setting screws 43-43 and forming mold 431.

According to the present invention, the mono-filament material feeding comes from the rotary feeder 30 of the mono-filament automatic constant rate feeding device which is driven by the rotary table 20, and the mono-filament is drawn out from the bobbin 50 at a revolving speed which is proportional to the speed of rotation of rotary table 20 at a fixed ratio, then, constant rate material feeding and helical oblique raising surface 400 of stationary forming mandrel 40 techniques are used for mono-filament feeding, and finally, the double pitch threads structure of setting screws 43-43 and forming mold 431 are used to setting and forming helical mono-filament coil into a desired zipper coil.Therefore, under automatic constant rate material feeding condition, mono-filament is fed at a pre-determined proper tension, it is not affected by centrifugal force which is generated by the roration of filament bobbin when mono-filament is drawing out, nor is affected by centering of filament bobbin axis and the remaining quality of mono-filament wound on filament bobbin, thus said mono-filament feeding and rotary feeding of filament bobbin defects are completely eliminated and material feeding now is controlled and fed at a constant rate, thus accurate pitch of zipper coil, uniform zipper teeth configuration, and good zipper elasticity are secured.Because push rod is replaced with a stationary forming mandrel and simple pitch screws is replace with a pair of double pitch setting screws, the forming speed is greatly increased, thus the productivity can be greatly promoted by increasing the operating speed of the zipper forming machine. Further more, because the revolving speed of rotary feeder of automatic constant rate feeding device is proportional to the rotation speed of rotary table 20 at a fixed ratio, thus no matter at what speed the rotary table 20 is rotating, it will not affect the automatic constant material feeding function, hence accurate pitch, uniform zipper teeth, and proper elasticity of zipper coil can be maintained as desired, especially the post-reworking of zipper teeth sewing can be easily done without thread and needle broken, thence productivity is greatly promoted, the waste is lowered to the least, production cost is greatly reduced.

For example, if simple pitch setting screws is used in the automatic constant rate feeding and forming device of the invention, and if the operating speed of the zipper forming machine is 2,000 rpm, then the speed of forming screws is 2,000 rpm too, at this condition, the production rate of the said zipper forming machine is 200 yards per hour. When compared with the conventional production rate of 60-70 yard per hour, the productivity of the former is promoted 3 times. If the single pitch setting screws are replaced with double pitch setting screws of this invention, the operating speed of the zipper forming machine can be easily increased to 3,600 rpm, and the speed of double pitch setting screw is decreased to 1,800 rpm, and the production rate is promoted to 360 yards per hour.Under this condition, not only the wear-out of the setting screws and forming mold can be reduced, life time of zipper forming machine can be extended, but productivity can be further promoted 1.8 time, therefore the invention has big contributions for the promotion of quality of zipper and the reduction of cost to a large extend.

From the foregoing descriptions and the embodiment mentioned of the invention, it is apparently that the technical bottle neck of the conventional zipper forming machine is broken through by the present invention.

The material feeding axis of the above said automatic constant rate feeding device is revolved by a gear 32 which is driven by rotary table 20 and engaged with gear portion 41 of forming mandrel 40, in this way automatic constant rate material feeding purpose is served by the revolving action of material feeding axis.

As mentioned above, the present invention utilizes the simplest device to make a big break-through on both operating speed and forming zipper coil pitch of a zipper forming machine, which making zipper forming machine can be operated at high speed in order to promote productivity and to secure good quality of zipper produced.

While a prefered embodiment has been described, variations there to will occur to those skilled in the art within the scope of the present invention concepts which are defined by the following claims.

Claims (10)

1. An automatic constant rate rotary feeding device for zipper forming machine comprising: a frame body; a rotary table rotatably mounted on said frame body; a mandrel means mounted at the center portion of said rotary table to support the rotation of said table; a bobbin loaded with mono-filament rotatably and moveably mounted on a stand under said table and synchronously rotated with said table; a forming core member firmedly mounted at top center of said mandrel means; a pair of setting screws provided at two sides of said core member;; a forming mold means encompassing said pair of setting screws and supported by said frame body, characterized in that an automatic constant rate feeding means is mounted on said table and rotating around said mandrel means and rotating with said table and capable of self-revolving with a constant rate in proportion to the rotational speed of said table whereby when said mono-filament is drawn from said bobbin and fed around said mandrel means and then further wound upward onto said forming core member by the aid of the top portion of said mandrel and said setting screws, then a continuous helical shaped filament coil are sequentially formed and come out from the top of said mold means.

2. A device as claimed in claim 1, characterized in that a gear portion is provided at the middle of said mandrel means and said feeding means comprises a supporting bracket means mounted on said rotary table, a gear shaft having a feeding axis at the top portion which is rotatably mounted in said supporting bracket means, a gear fixed on said gear shaft and positioned in engagement with said gear portion of said mandrel means so that during operation the rotation of said table will enable said feeding means to rotate around said mandrel means.

3. A device as claimed in claim 1, characterized in that said mandrel means stays stationary at the center of said rotary table to support the rotation of said rotary table.

4. A device as claimed in claim 1, characterized in that said mandrel means further comprises a helical oblique raising surface at the top portion which is consisted of a front half conical body and a rear half conical body.

5. A device as claimed in claim 4, characterized in that the height of tip part of front conical body of said mandrel means is higher than that of the rear half one and the configuration of two half bodies are not symmetrical with each other.

6. A device as claimed in claim 4, characterized in that the slope on right sides of said front and rear half conical bodies are greater than that on the left sides of the same.

7. A device as claimed in claim 1, characterized in that said feeding means further comprises a tension adjusting means installed on said rotary table at a position opposite to said feeding means.

8. A device as claimed in claim 1, characterized in that said feeding axis of the feeding means further comprises an oblique conical guiding surface and a slipless axis are provided at one end thereof on which mono-filament is wound.

9. A device as claimed in claim 8, characterized in that mono-filament wound on said feeding axis is at least one turn.

10. An automatic constant rate rotary feeding device substantially as hereinbefore described with reference to the accompanying drawings.