JPH046012A - Multi-step stretching device for stretch packaging machine - Google Patents

Abstract

PURPOSE:To obtain a stretching device by which high magnification stretching is available using general purpose films, and for which stretching magnification can be easily set in many steps by feeding a stretch film from idly rotating rolls having same diameters for guiding and drawing which are located between respective rolls excepting a first roll, through a dancer roll, to an object to be packaged. CONSTITUTION:Drive gears 11b-15b having same diameters which are axially attached to the rotary shafts of respective rolls 11-15 are driven while being engaged in order. At the same time, a first guide idly rotating roll 16 to draw a film from a second roll, a second guide idly rotating roll 17 to draw the film from a third roll, a third guide idly rotating roll 18 provided between a fourth roll and fifth roll, let out idly rotating rolls 19, 20 and dancer rolls 21, 22 are provided respectively with the same diameter or optional diameters. When a film F is let out from a film roll 4 through the idly rotating rolls 16, 19 from the first roll 11, non-stretch packaging is performed, and when the film F is let out in the same manner through the second roll 12, the doubly stretched film is wound around an object to be packaged. Therefore, not only respective connecting gears but idly rotating rolls also can have the same diameter, and types of parts can be reduced, and the device can be produced with a low price.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that can set the stretching ratio of a film in multiple stages in a film stretch packaging machine.

(Prior art) There are two methods for wrapping a stretched film around the packaged items loaded on a pallet:
A method is known in which a film that has been stretched to a predetermined magnification is wound without tension, but in any of these methods, the conventional stretching means is based on the mutual rotation ratio of two stretching rollers as shown in Figure 1. The paper is stretched using the difference in the number of concave roller rotations.

Therefore, a special film such as a multilayer film of low density polyethylene is required.

(Objective) The present invention provides a stretching device that is capable of high-stretching stretching using a commonly used film, and that can easily set the stretching ratio in multiple stages.

(Structure) The apparatus of the present invention includes a first roll driven via a transmission on a support base that can be raised and lowered relative to the packaged object on a turntable, and a second roll having a diameter twice that of the first roll. 2 rolls, a third roll having a diameter three times the diameter of the first roll, a fourth roll having a diameter four times the diameter of the first roll, and a diameter five times the diameter of the first roll. Fifth
The rolls are arranged vertically, and transmission gears of the same diameter that are mounted on the rotating shaft of each roll are meshed and driven in order with the rolls, and are located between each roll except the first roll. The drawer guide is configured such that idler rolls of the same diameter for guiding the drawer are vertically disposed, and the stretched film from each of the idler rolls is supplied to the article to be packaged via a dancer roll.

The above apparatus will be explained with reference to the embodiment shown in the figure.

(Example) 1 is a column, 2 is an elevating carriage, 3 is an arm, 4 is a film roll, 5 is a support stand, 6 is a motor, and 7 is a transmission.

11 is the first roll (diameter D = 20cm), 12 is the second roll (D = 40cm), 13 is the third roll (D
= 60cm), 14 is the fourth roll (D = 80cm
),, 15 is the fifth roll (D=1m).

16 is a first guide idle roll that pulls out the film from the second roll, and 17 is a second guide roll that pulls out the film from the third roll.
A guide idler roll, 18 is a third guide idler roll provided between the fourth roll and the fifth roll, 19.20 is a feeding idler roll, and 21.22 is a dancer roll. Have any diameter.

The rotating shafts 11a, 12a, 13a, 14a, 15a of each roll from the first roll 11 to the fifth roll 15 pass through the support base 5, and a transmission gear 11b having the same diameter is provided at the lower end.
, 12b, 13b, 14b and 15b, and the gears are meshed and connected in series in the above order.

Therefore, the rotating shafts that are transmission-driven from the continuously variable transmission 7 via the belt 9 and pulley 10 are all rotated at the same number of rotations, but the circumferential speed of each shaft increases in proportion to the diameter.

Reference numerals 30 and 31 are frames that hold the ends of each rotating shaft.

(Function) When the film F from the film roll 4 is fed out from the first roll 11 via the idler rolls 16 and 19, non-stretch packaging is performed.

When similarly fed out via the second roll 12, the stretched film stretched twice is wound around the packaged object.

Further, the material that has passed through the third roll 17 is stretched 3 times, and the material that has passed through the fifth roll is stretched 5 times.

(Effects) In the present invention, each stretching roll is connected in series and driven, so the film is stretched under a strong tensile force due to the action of the hemiwheel of each roll, and the film is gradually stretched between each roll. Since it is stretched, it can be stretched to a desired magnification without breaking without using a special dedicated film.

Furthermore, in order to obtain a desired stretching ratio, unlike the conventional apparatus, a rotation ratio setting mechanism is not required, which simplifies the structure.

In addition, in the present invention, although the diameters of the stretching rolls are different, the diameters of not only the connecting gears but also the idler rolls may be the same, which has the advantage of requiring fewer types of parts and producing an apparatus at a low cost.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an example of a conventional apparatus, FIG. 2 is a plan view of essential parts of the present invention, and FIG. 3 is a partial side view showing a drive system for each stretching roll. Explanation of drawing symbols 11 to 15 are respective stretching rolls, llb to 15b are respective transmission gears, and 16 to 21 are idle rolls, respectively, patent applicant
Representative of Tsukasa Kasei Kogyo Co., Ltd.
Hiroshi Nakamura Diagram Diagram

Claims (1)

[Claims] A first roll that is driven via a transmission to a support base that can be raised and lowered relative to the packaged object on a turntable, a second roll that has twice the diameter of the first roll, and a second roll that has a diameter twice that of the first roll; a third roll having a diameter three times that of the first roll; a fourth roll having a diameter four times that of the first roll;
A fifth roll having a diameter five times that of the roll is disposed perpendicularly, and transmission gears having the same diameter and attached to the rotating shaft of each roll are meshed with each roll in order and driven, Drawer guiding idler rolls having the same diameter are vertically disposed between each roll except for the first roll, and the stretched film from each of the idler rolls passes through a dancer roll to the packaged item. Multi-stage stretching device in supplied stretch wrapping machine.