WO2004007294A1

WO2004007294A1 - Electronic band ejecting tensioner of automatic packing machine

Info

Publication number: WO2004007294A1
Application number: PCT/KR2002/001838
Authority: WO
Inventors: Jun-Ho An; Ho-Soon Ha; Jae-Moon Kim; Gi-Won Song; Sang-Sik Choi
Original assignee: Dong Seo Inc.
Priority date: 2002-07-15
Filing date: 2002-09-28
Publication date: 2004-01-22
Also published as: KR200292370Y1

Abstract

Disclosed is an electronic band ejecting tensioner of an automatic packing machine which prevents a band from being damaged or cut when there is no object to be packed, thereby solving inconvenience of removing the band and minimizing failure rate. In the automatic packing machine 1, a cadmium sulfide cell 6 automatically detects whether there exists an object to be packed, a solenoid 7 operates in response to a sensing signal of the cadmium sulfide cell 6, and a tension jaw 14 mounted on a tension arm 3 clamps or unclamps a band 16. Accordingly, the present invention has advantages of certainly preventing wrong operation by detecting the existence of the object in advance, minimizing failure rate and manufacturing costs by simplifying the structure of the apparatus, and solving inconvenience of manually removing the band 16 by automatically ejecting the band 16 from the inside of the automatic packing machine.

Description

ELECTRONIC BAND EJECTING TENSIONER OF AUTOMATIC

PACKING MACHINE

Technical Field

The present invention relates to an electronic band ejecting tensioner of an automatic packing machine, and more particularly, to an electronic band ejecting tensioner of an automatic packing machine which prevents a band from being damaged or cut when a packing process is performed with no object to be packed, thereby solving inconvenience of removing the band and minimizing failure rate.

Background Art

In general, when an object needs to be packed, an operator uses an automatic packing machine in such a manner that he or she manually adjusts tension and then lets the automatic packing machine packing the object by means of a band. If the packing process using the band is performed in a state where there is no object to be packed due to his or her mistake, the band packs the front surface of a slide table, such that when there is tension, the band is damaged or cut. The operator should creep under the slide table and remove the band with his or her hands to operate the automatic packing machine again.

The band's wrong operation causes a mechanical failure in the automatic packing machine. Therefore, if there is no object to be packed on the slide table, there is an urgent need to detect whether there is an object to be packed and prevent tension from being applied.

There have been suggested many types of band ejecting tensioners. Conventionally, if the packing process using band is performed with no object to be packed, a detecting lever installed at the lower portion of the slide table detects whether there is no object to be packed in such a manner as to activate a contact point of a micro switch while being angularly moved according to tension of the band, and then such a driving source as a motor or a solenoid in the tensioners operates to unclamp the band from the tensioners.

The conventional electronic band ejecting tensioners, however, have drawbacks in that their structures are complicated, thereby increasing manufacturing costs, mechanical mechanisms are complicated, and failure rate in the portion of the sensing lever is high. Thus, there are demands for developing apparatuses capable of solving the drawbacks.

Disclosure of Invention

Accordingly, the present invention is directed to an electronic band ejecting tensioner of an automatic packing machine that substantially obviates one or more problems due to limitations and disadvantages of the related art.

An object of the present invention is to provide an electronic band ejecting tensioner of an automatic packing machine which prevents a band from being damaged or cut due to tension when there is no object to be packed, thereby minimizing failure rate in the apparatus. Another object of the present invention is to provide an electronic band ejecting tensioner of an automatic packing machine which can detect whether there is placed an object to be packed in advance in an exacter manner to unclamp a band from the tensioner and also can eject the band to the outside by means of an ejector lever to prevent the band from being damaged or cut. Still another object of the present invention is to provide an electronic band ejecting tensioner of an automatic packing machine whose structure is so simple that it can be mounted at a low cost and can minimize failure rate.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Brief Description of the Drawings

The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating the entire structure of an automatic packing machine according to the present invention;

FIG. 2 is a schematic plan view illustrating the state in which an electronic band ejecting tensioner is installed according to the present invention; FIG. 3 is a front view especially illustrating a tension arm in the electronic band ejecting tensioner according to the present invention;

FIG. 4 is a side view especially illustrating the tension arm in the electronic band ejecting tensioner according to the present invention;

FIGs. 5a and 5b are enlarged front views illustrating the state in which a tension lever and a tension jaw operate according to the present invention;

FIGs. 6 to 8 are cross-sectional views illustrating the state in which an ejector lever operates according to the present invention; and

FIG. 9 is a plane view illustrating the state in which the ejector lever operates according to the present invention.

Best Mode for Carrying Out the Invention

The present invention will now be described in detail in connection with preferred embodiments with reference to the accompanying drawings. For reference, like reference characters designate corresponding parts throughout several views.

FIG. 1 is a perspective view illustrating the entire structure of an automatic packing machine 1 according to the present invention. FIG. 2 is a schematic plan view illustrating the state in which an electronic band ejecting tensioner 2 is installed according to the present invention. FIG. 3 and FIG. 4 are a front view and a side view, respectively, illustrating a tension arm 3 in the electronic band ejecting tensioner 2 according to the present invention.

Referring to FIGs. 1 through 4, a cadmium sulfide cell 6 is mounted on one side of a slide table 5, which is installed on the upper surface of a sealing head unit 4 in an automatic packing machine 1, so as to detect whether there exists an object to be packed on the upper surface of the slide table 5. A solenoid 7 is installed on one side of the automatic packing machine so as to operate in response to a sensing signal of the cadmium sulfide cell 6. The cadmium sulfide cell 6, called 'Cds Cell', is a photoconductive cell using Cds which is a compound of cadmium and sulfide.

A wire 9 is, at one end thereof, fixedly connected to an operation rod 8 of the solenoid 7, and at the other end thereof, connected to a tension lever 12 which is elastically mounted by means of a torsion spring 11 on a tension jaw shaft 10 at the upper portion of a tension arm 3.

A tension jaw 14 on which a hook 13 is formed is also fixedly mounted on the tension jaw shaft 10 such that if the operation rod 8 of the solenoid 7 is pulled and the hook 13 is pushed by the tension lever 12, the tension jaw 14 clamps a band 16 which passes through a band guiding slot 15, whereas if the tension lever 12 is pushed by the operation rod 8 of the solenoid 7, the tension lever 12 and the tension jaw 14 are angularly moved due to elasticity of a torsion spring 11, one end of which is elastically installed at the hook 13, so as to unclamp the band 16. The wire 9 connecting the operation rod 8 of the solenoid 7 and the tension lever 12 is embedded into a flexible tube 17 so as to operate there.

Meantime, an ejector lever 19 is mounted on one side of the slide table 5 so as to be angularly moved using a pin 18 as a rotating axis, and a spring 20 is elastically installed at the rear end of the ejector lever 19.

Reference numeral 21 designates a lower cutter; 22 a feed roller; 23 a control frame; 24 a slide cover; and 25 an object to be packed.

In the electronic band ejecting tensioner 2 of the automatic packing machine 1, depending on whether or not the object to be packed is placed on the upper surface of the slide table 5, a tensional force of the band 16 is produced so that the band is fastened, or a tensional force of the band 16 is canceled so that the band 16 is released. The operation of the electronic band ejecting tensioner 2 will be described below in further detail.

When there exists the object 25 to be packed on the upper surface of the slide table 5, the cadmium sulfide cell 6 detects the existence of the object to be packed and applies a sensing signal to the solenoid 7. The operation rod 8 is pulled and the tension lever 12 which is formed on the tension arm 3 and connected to the operation rod 8 by means of the wire 9, overcomes elasticity of the torsion spring 11 and pushes the hook 13 while being angularly moved clockwise on the tension jaw shaft 10 as shown in FIG. 5b. At this time, the tension jaw 14 connected to the hook 13 is also angularly moved clockwise so as to clamp the band 16 which passes through the band guiding slot 15. While the band is clamped, the tension arm 3 is angularly moved at the same time, so that the object 16 is packed by means of the band 16 with tension. Thereafter, a heater mounted at the upper surface of the sealing head unit 4 operates to fasten the ends of the band 16 through a thermal bonding method, thereby completely packing the object 25. If an operator operates a switch for packing the object 25 by his or her mistake although there is no object to be packed on the upper surface of the slide table 5, the cadmium sulfide cell 6 doesn't perform its sensing operation and accordingly the sensing signal is not applied to the solenoid 7. Consequently, the band 16 passing through the band guiding slot 15 is undamped by the tension jaw 14 as depicted in FIG. 5a. Therefore, even though the tension arm 3 is angularly moved, the tensional force of the band 16 is not produced. As a result, the band 16 is prevented from being damaged or cut on the slide table 5, a possibility of mechanical failure caused when the band 16 is inserted into the inside of the automatic packing machine is removed, and inconvenience of manually removing the band 16 is solved.

On the other hand, the ejector lever 19, as shown in FIGs. 7 to 9, functions to automatically eject the band 16. When there exists the object to be packed on the upper surface of the slide table 5 as shown in FIG. 6, the band 16 is not in contact with the ejector lever 19. However, when there is no object to be packed on the upper surface of the slide table 5 as shown in FIG. 7, the band 16 is ejected in such a manner as follows.

As shown in the general automatic packing machine, when the feed roller 22 pulls the band 16, the band 16 pulls the ejector lever 19 rightward and thereafter the lower cutter 21 cuts the band 16. The cut band 16 is bonded by using the heater. The bonded band 16 becomes a substantially elliptical loop in shape when being seen from the front side. While the front surface of the ejector lever 19 is moved leftward by the spring 20 which elastically supports the rear side of the ejector lever 19, the ejector lever 19 pushes the elliptical loop-shaped band 16. When the slide table 5 is backwardly moved, the band 16 collides with the slide cover 24 which is fixedly mounted on the upper surface of the control frame 23, namely the slide table 5, whereby the loop-shaped band 16 is upwardly ejected.

Industrial Applicability

As described above, in the electronic band ejecting tensioner 2 of the automatic packing machine 1, the cadmium sulfide cell 6 automatically detects whether or not there exists the object to be packed, the solenoid 7 operates in response to the sensing signal of the cadmium sulfide cell 6, and thus the tension jaw 14 mounted on the tension arm 3 clamps or unclamps the band 16. Accordingly, the electronic band ejecting tensioner 2 has an advantage that wrong operation can be certainly prevented by detecting the existence of the object to be packed in advance. The electronic band ejecting tensioner 2 has another advantage that failure rate is minimized and manufacturing costs are reduced by simplifying and stabilizing the structure of the apparatus. The electronic band ejecting tensioner 2 has yet another advantage that inconvenience of manually removing the band 16 is solved by automatically ejecting the band 16 from the inside of the automatic packing machine.

While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

Claims

What Is Claimed Is:

1. An electronic band ejecting tensioner of an automatic packing machine for automatically removing tension applied to a band(16) and ejecting the band(16) when no object to be packed is placed on the upper surface of a slide table(5), the electronic band ejecting tensioner comprising: a cadmium sulfide cell(6) mounted on one side of the slide table(5), which is installed on the upper surface of a sealing head unit(4), and adapted to detect whether there exists an object to be packed; a solenoid(7) installed on one side of the automatic packing machine and adapted to operate in response to a sensing signal of the cadmium sulfide cell(6), the solenoid(7) having an operation rod(8) one end of which is connected to a wire(9) connected to a tension lever(12) which is elastically mounted by means of a torsion spring(l l) on a tension jaw shaft(lθ) at the upper portion of a tension arm(3); a tension jaw( 14), having a hook(13), fixedly mounted on the tension jaw shaft(lθ) and adapted to optionally clamp the band(16), which passes through a band guiding slot(15), while cooperating with the tension lever(12); and an ejector lever(19) elastically mounted by means of a spring(20) on one side of the slide table(5) in such a manner as to be angularly moved using a pin(18) as a rotating axis, and adapted to eject the band(16).