AU753136B2 - Device for forming ventilation holes on a plastic film of a shrinking film packaging machine - Google Patents

Description

TITLE: DEVICE FOR FORMING VENTILATION HOLES ON A PLASTIC FILM OF A SHRINKING FILM PACKAGING

MACHINE

BACKGROUND OF THE INVENTION 5 1. Field of the Invention This invention is related to a device for forming ventilation holes on a plastic film of a shrinking film packaging machine.

#oo• 2. Description of the Prior Art Those skilled in the art are familiar with the techniques for packaging different products inside wraps of plastic film. The conventional packaging .:oo.i system of such a type consists in forming envelope containing the product to S.be packaged and a heat source and means for hot air circulation are provided to shrink the envelope. It is necessary to form ventilation holes of the plastic film for the passage of hot air when the film is shrunk in order to ensure the shrinking of the film and so it has been proposed to use a device for forming ventilation holes on the plastic film to achieve this purpose. Such a conventional device for forming ventilation holes on a plastic film of a shrinking film packaging machine includes an axle, a plurality of cylinders mounted on the axle, and a row of needles arranged on each of the cylinders.

However, the conventional device suffers from the following drawbacks: 1. It is necessary to adjust the position of the cylinders in order to enable the needles to form ventilation holes evenly on a plastic film thereby wasting a lot of time for the adjustment.

2. The cylinders must be separately fitted on the axle and then fixedly mounted by bolts thus causing much inconvenience in operation and making it very difficult for maintenance.

:oooi 3. As the cylinders are fixedly mounted on the axle by bolts so that once the bolts are loose, the cylinders will be rotated with the plastic film hence breaking the plastic film.

10 Therefore, it is object of the present invention to provide an .:oo.i S:"i improvement in the structure of a device for forming ventilation holes on a plastic film of a shrinking film packaging machine which can obviate "i and mitigate the above-mentioned drawbacks.

SUMMARY OF THE INVENTION This invention is related to a device for forming ventilation holes on a plastic film of a shrinking film packaging machine.

It is the primary object of the present invention to provide a device for 5 forming ventilation holes on a plastic film of a shrinking film packaging machine which will form a plurality of ventilation holes on a film at ooooo predetermined positions when the axle is rotated, thereby enabling air to be forced rapidly out of the package when the film is shrunk at sealing.

It is another object of the present invention to provide a device for 10 forming ventilation holes on a plastic film ofa shrinking film packaging ooooo machine wherein the position of the needles is determined by the holes of the seat thereby keeping the distance between the needles and therefore eliminating the adjustment of the needles.

It is another object of the present invention to provide a device for forming ventilation holes on a plastic film of a shrinking film packaging machine wherein the seats can be rapidly inserted into the axle and removed from the axle thereby facilitating the assembly and maintenance.

It is a further object of the present invention to provide a device for forming ventilation holes on a plastic film of a shrinking film packaging machine which can still form ventilation holes on a plastic film even if the fixing bolt is loose.

According to a preferred embodiment of the present invention, a device for forming ventilation holes on a plastic film of a shrinking film packaging machine includes a tubular axle having outer surface formed with a plurality 5 of longitudinal dovetail grooves, a plurality of seats having a trapezoid cross section configured to fit into the longitudinal grooves of the tubular axle and .:oooi having two vertical holes, a threaded hole between the two vertical holes, and two horizontal threaded holes at two ends thereof, each of the horizontal threaded holes being in communication with a respective one of the vertical 10 holes, a plurality of needles each having a pointed upper end and inserted into .oo..i a respective one of the vertical hole of the seat, with the pointed upper end protruded out of a respective one of the vertical holes, a first bolt engaged with the threaded hole, and two second bolts engaged with the two horizontal holes to bear against the needles to secure the needles in the seat, whereby the position of the needles is determined by the holes and the seats are inserted into the grooves of the axle so that the needles 24 will form a plurality of ventilation holes on a film at predetermined positions when the axle is rotated, thereby enabling air to be forced rapidly out of the package when the film is shrunk at sealing.

The foregoing objects and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying 5 drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts. Many other advantages and .oooo: features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying S.sheets of drawings in which a preferred structural embodiment incorporating 10 the principles of the present invention is shown by way of illustrative example.

oo.o.i o.ooooo0 o i 6 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a shrinking film machine on which a mounted a device for forming ventilation holes on a plastic film according to the present invention; FIG. IA is an enlarged perspective view of a portion of FIG. 1; FIG. 2 is an exploded view of the seat; FIG. 3 is an exploded view of the axle; and FIG. 3A is a sectional view of the axle.

*o* ooo *ooo*o* DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings. Specific language will be used to describe same. It will, 5 nevertheless, be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated o:oo* device, and such further applications of the principles of the invention as illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates.

10 With reference to the drawings and in particular to FIGS. 1 and 1 A, the ooooo present invention is mounted on a packaging machine 5 and generally comprises an axle 1, a plurality of seats 2 and a plurality of needles 24. The axle 1 is a tubular member formed with a plurality of longitudinal dovetail grooves 11 on the surface thereof. The seat 2 is of a trapezoid cross section configured to fit into the longitudinal dovetail groove 11 and has two vertical holes 26, a threaded hole 20 between the two vertical holes 26, and two horizontal threaded holes 25 at two ends thereof(see FIG. Each of the horizontal threaded holes 25 is in communication with a respective one of the vertical holes 26. The needle 24 has a pointed tip at the upper end.

The needle 24 is inserted into a respective vertical hole 26 of the seat 2, with its pointed tip at the upper end protruded out of the hole 26. A bolt 23 is turned into a respective threaded hole 25 of the seat 2 so as to bear against the needle 24 thereby keeping the needle 24 in a fixed position (see FIG. 3A).

Then, the seats 2 are inserted into respective grooves 11 of the axle 1 (see FIG.

5 Finally, a bolt 21 is turned into the threaded hole 20 of the seat 2 for moving the seat 2 to go upwardly against two opposite sides of the dovetail 11 ooooo thereby firmly securing the seat 2 in a fixed position.

As the position of the needles 24 is determined by the holes 26 and the seats 2 are inserted into the grooves 11 of the axle 1, the needles 24 will form a 10 plurality of ventilation holes 41 on a film 4 at predetermined positions when o:..oi the axle 1 is rotated, thereby enabling air to be forced rapidly out of the package when the film is shrunk at sealing.

"It should be noted, however, that the dovetail groove 11 and the seat 2 may be replaced with a rectangular groove and a rectangular block for facilitating the manufacture thereof and the rectangular block is directly fixed on the rectangular groove by a bolt.

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without i 5 departing in any way from the spirit of the present invention.

Claims (3)

1. A device for forming ventilation holes on a plastic film of a shrinking film packaging machine comprising: a tubular axle having outer surface formed with a plurality of 5 longitudinal dovetail grooves; S. a plurality of seats having a trapezoid cross section configured to fit into said longitudinal grooves of said tubular axle and having two vertical holes, a threaded hole between said two vertical holes, and two horizontal threaded holes at two ends thereof, each of said horizontal threaded holes being in communication with a respective one of said vertical holes; a plurality of needles each having a pointed upper end and inserted into a respective one of said vertical hole of said seat, with said pointed upper end protruded out of a respective one of said vertical holes; a first bolt engaged with said threaded hole; and two second bolts engaged with said two horizontal holes to bear against said needles to secure said needles in said seat.

2. The device for forming ventilation holes on a plastic film of a shrinking film packaging machine as claimed in claim 1, wherein said dovetail grooves and said seats are respectively replaced with a rectangular groove and a rectangular block for facilitating manufacture thereof and said rectangular block is directly fixed on said rectangular groove by a bolt. Dated 14 November, 2000 Chao Yi Chiu :"ee Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON 0 0 00.0* *0O

060. 0:04