JPS6037281Y2 - stretch wrapping equipment - Google Patents

Description

[Detailed description of the invention] The present invention is a stretch wrapping device, in particular, a pair of left and right clamps is used to feed and stretch a stretch film to a predetermined position above an elevator, and the elevator lifts the object to be wrapped, pushing it up against the film and wrapping it. The present invention relates to improvements during the body wrapping process in a stretch wrapping device.

In conventional equipment, in the process of pushing up the packaged item using an elevator, etc., and wrapping it in a film, both the left and right clamps are fixed in place, which means that the tension of the film is kept constant when the packaged item is pushed up. It is a structure.

However, with the above-mentioned conventional structure, hard objects such as apples, pears, or boxed products can be wrapped well, but if the objects are soft, such as pine mushrooms and mushrooms, the tension of the film will cause the objects to be wrapped. There is a problem that the product value is reduced by being crushed.

The purpose of this invention is to prevent the product from being crushed or damaged during packaging by adjusting the film tension depending on the item to be packaged, and to eliminate sagging of the film to improve the appearance of the packaged product. and is characterized by providing means for moving both clamps toward the center of the film by a predetermined amount depending on the object to be packaged, during the elevator ascending process, from the time when the object to be packaged and the film come into contact with each other to the upper limit position of the elevator. shall be.

An embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 is an elevator, 2 and 2' are a pair of left and right opposing clamps, 3 and 3' are folding plates, and 4 is a packaged product 5. A conveyor 6 for transporting the film onto the elevator 1 is a stretch film which is led out from a film roll 6' and is inserted and held in the clamp 2' via a tight roller 7 and rollers 8 and 8'.

The above-mentioned product 5 is shown to be packaged on a tray 5'.

The clamps 2, 2' are slidably supported by a guide member such as a guide rod, and are movably installed horizontally above the elevator 1 at a predetermined distance.

The left and right clamps 2, 2' are set to be at symmetrical positions with respect to the uplifting center line a of the product 5 (the figure shows a case where the center line coincides with the center line of the elevator 1).

Each of the clamps 2, 2' is constructed by assembling upper and lower pieces so that they can be opened and closed by a solenoid or the like, and when the clamps are closed, the stretch film 6 is clamped, and when the clamps are opened, the film 6 is released.

Each clamp 2, 2' has a zigzag shape in which each opposing line is alternately arranged with concave portions and convex portions, and both clamps 2 and 2'
, 2' are fitted into each other, and when the clamps 2 and 2' are brought close to each other, both the top and bottom of the clamp 2 are fitted at the position where the protrusion of the clamp 2 is fitted into the recess of the clamp 2'. The film 6 is held between the protrusions.

Each of the clamps 2, 2' has a drive shaft 10, 10 which rotates with an electric drive source 9, 9' such as a pulse motor, respectively.
' are connected, and each clamp 2, 2 is made movable by rotation of the drive shaft 10, 10'.

It is also possible to use other electrical or mechanical drive devices such as a chino or a gear mechanism in place of the drive shafts 10 and 10' connected to the drive sources 9 and 9'.

The clamps 2 and 2' hold the starting end of the film 6 between the right clamp 2', and the left clamp 2 moves toward the clamp 2' by activation of the drive source 9, opening the upper and lower parts. When the clamp 2' opens after clamping the starting end of the film 6 in the vicinity of the clamp 2', the clamp 2 performs a reciprocating motion to return to its original position, thereby feeding the film 6 and causing the clamp 2 to return. At the end of the movement, the clamp 2 is moved to close and the film 6 is stretched over the elevator 1 (FIGS. 1 and 2).

The film 6 is fed out using the clamp 2 described above.
This is not limited to the reciprocating motion of the clamps 2 and 2', but any method may be used, such as mutual reciprocating motion of the clamps 2 and 2'.

Next, the elevator 1 starts to move up and the product 5 is pushed up.
move in the direction of the thrust center line a while holding the film 6 between them.

That is, the elevator 1 starts to ascend and the product 5 collides with the film 6 (Fig. 3), or the elevator 1 moves to the upper limit position after the time set by the timer has elapsed after ascending (Fig. 4).
Both clamps 2, 2' are made to move during the process of reaching .

The clamps 2, 2' are moved by driving the drive sources 9, 9', and the movement conditions such as movement timing, movement amount, and movement speed are determined by, for example, a central processing unit (optional).
A microcomputer control method may be adopted in which a plurality of types of data corresponding to the product 5 are stored in u), and appropriate values from the data are selected by input operations and outputted to the drive sources 9 and 9'.

The data corresponding to the above product 5 is the condition for determining the film tension according to the hardness or softness of the product 5, the height of the product 5, or the dimensions of the tray 5' relative to the film length. If it is soft like
Set the amount of movement larger than for hard objects such as apples and pears.

The amount of movement of the clamps 2, 2' includes a case where the movement amount is zero, that is, the movement is not caused by the product 5.

It is preferable that the movement conditions of the left and right clamps 2, 2' be the same, so that the film tension can be maintained uniformly on the left and right sides.

As a result, the product 5 is pushed up by the elevator 1, and the film 6 is wrapped in tension along the top and left and right sides of the product 5.
When the elevator 1 reaches the upper limit position, the folding plates 3, 3
By the folding operation of ', both left and right sides of the film 6 are tensed and folded into the bottom of the product 5, wrapping the product 5 in a wrapper shape (
Figures 5 and 6).

After that, the product 5 is packaged by folding and polymerizing the film edges protruding from the front and back along the bottom of the product.
(not shown).

Note that 11 in the figure is a cutter.

As described above, the present invention provides a means for moving both clamps toward the center of the film during the elevator ascent process, from the time when the object to be packaged hits the film to the upper limit position of the elevator. Since the clamp is moved by an appropriate amount depending on the shape, the tension of the film that is generated when the packaged object collides with the elevator and ascends is adjusted by the movement of the clamp.

Therefore, it is possible to prevent excessive or insufficient tension from being applied to the packaged item and stretch wrap it with the appropriate tension depending on the packaged item, and when packaging soft items such as pine mushrooms. However, it is possible to eliminate the problem of damage such as crushing of the packaged item, and also to eliminate sagging of the film, thereby improving the packaging finish and improving the appearance.

Therefore, the intended purpose can be achieved.

[Brief Description of the Drawings] Fig. 1 is a front view of the device of the present invention, Fig. 2 is a front view illustrating its film feeding operation, Figs. 5 to 6 are front views illustrating the folding operation. In the figure, 1 is an elevator, 2°2' is a clamp, 5 is packaging, 6 is a stretch film, 9°9' is a drive source, and 10°10' is a drive shaft.

Claims (1)

[Scope of utility model registration request] In a stretch packaging device, a stretch film is drawn out and stretched at a predetermined position above an elevator by a pair of left and right clamps, and the object to be packaged is raised by the elevator and pushed up and wrapped on the film. A stretch packaging device comprising means for moving both clamps toward the center of the film by a predetermined amount depending on the object to be packaged, from the time when the clamps collide with the film to the upper limit position of the elevator.