JPH069923Y2 - Stretch wrapping machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a stretch wrapping machine, and more particularly, to an improvement of a stretch wrapping machine with a device for holding an object to be wrapped.

[Conventional technology]

During the stretch wrapping, a device for pressing a packaged object placed on a rotating rotary table to press the upper surface of the packaged object to stabilize the packaged object has a lifting arm 8 as shown in FIG.
And a flanged shaft 21 that is rotatably attached to the tip of the lifting arm and a holding plate 7 fixed to the shaft. In the early stretch wrapping machine, the holding plate 7 was directly screwed to the shaft 21 by the screw 22 as shown in FIG. 6, but when the upper surface of the article to be wrapped 5 is not flat as shown in the figure, Only the highest part can be pressed, and the function as a device for pressing the object to be packaged cannot be fully exerted.

For this reason, in recent years, improvements have been attempted as shown in FIG.
That is, the device shown in FIG. 7 has a holding plate 7 and a shaft 2
The steel ball 24 is sandwiched between the two and the pressing plate 7 and the shaft 21 are screwed with the screw 22 via the spring 23 so that the pressing plate 7 can be tilted to some extent. In another stretch wrapping machine, the press plate 7 can be tilted by connecting the shaft and the press plate via a spherical bearing.

[Problems to be solved by the invention]

By the way, in the stretch wrapping machine, by design, the center of the rotary shaft of the rotary table 2 and the center of the rotary shaft of the holding plate 7 of the object-to-be-packaged holding device 6, that is, the center of the shaft 21 should be exactly aligned. Actually, the holding plate 7 is the turntable 2
Since it is provided at a distance of 1 meter or more from the upper side and is supported by a vertically movable lifting arm 8, the center of the rotary shaft of the rotary table 2 and the center of the shaft 21 can be accurately aligned. Is difficult, usually 2
The reality is that it is eccentric in the range of 3 millimeters.
Therefore, the center of the pressing plate 7 is 2 to 3 on the upper surface of the article to be packaged 5.
Circular movement with a radius of millimeter, holding plate 7 and shaft 2
If the wear of the screws 22 and the like that connect with 1 is made severe, or if the upper surface of the object to be packaged is stretch-wrapped with a film or paperboard, the position of the film or paperboard will shift during the packaging process. Often occurred.

The present invention has been made to solve these drawbacks.
The purpose is that when the holding plate is placed on the top surface of the packaged object,
A device for pressing an object to be wrapped which is tiltable along the upper surface and is rotatable with the object to be wrapped around the axis of rotation of the table even if the center of the holding plate and the axis of rotation of the table are slightly deviated. It is to provide a stretch wrapping machine equipped with.

[Means for solving problems]

In the stretch wrapping machine of the present invention which achieves the above-mentioned object, a rotary table 2 on which an article 5 to be packaged is placed, a pressing plate 7 for pressing the upper surface of the object to be packaged on the rotary table, and a lifting arm for supporting the pressing plate. Mainly comprises a device 6 for holding the object to be packaged 6, and a film unwinding mechanism 4 for vertically arranging the film winding device 3 for packaging vertically on the rotary table and holding the film film rewinding device. In the stretch wrapping machine, the pressing plate 7 and the elevating arm 8 are slidable on the inner periphery of the collar 13a and the bottom thereof, with the tubular body 13 with the collar 13a and the collar 14a engaging with the collar 13a. The presser plate 7 contacts the upper surface of the object to be packaged 5, and is connected to the inner periphery of the flange 13a of the tubular body 13 while being connected with the engaging element 12 formed of the weight-like body 14 which is movably fitted. The pressing plate 7 is covered with the taper portion of 14 By detecting that the elevating arm 8 has descended to a position at which a sufficient distance t is formed so as to be tiltable along the upper surface of the article 5 and rotatable about the rotation axis of the packaged object, It is characterized in that a detection device 9 for stopping the lifting arm is provided.

[Action]

In the stretch wrapping machine of the present invention, due to the structure described above,
When the holding plate 7 presses the upper surface of the article to be packaged 5, there is a space t between the inner surface of the flange 13a of the tubular body 13 and the tapered portion of the weight body 14, and the holding plate 7 moves up and down during the packaging process. Arm 8
Is released from the support of the package 5 and is tiltably placed along the upper surface of the package 5 and rotates with the package 5 even if the center of the holding plate 7 and the rotation axis of the rotary table 2 are slightly deviated. The table 2 is rotated about the axis of rotation, so that the center of the holding plate 7 makes a circular motion with a small radius on the upper surface of the object to be packaged 5, and the fixing screw on the holding plate and / or the lifting arm is severely worn. The effect that it is possible to avoid displacing the film or the paperboard covered on the upper surface of the article to be packaged is achieved.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.

FIG. 1 shows an embodiment of the present invention (hereinafter referred to as the first embodiment).
2 is a side view of the stretch wrapping machine of FIG. 2, and FIG. 2 is a partial cross-sectional view of the holding plate attachment portion of the object holding device of the stretch wrapping machine of FIG. The upper surface is not pressed, and Fig. 2b shows the pressed state.

In the figure, symbol 1 is a base frame, 2 is a rotary table, 3
Is a film winding mechanism, 4 is a film unwinding mechanism, 5 is an object to be packaged, 6 is a device for holding an object to be packaged, 7 is a holding plate, 8 is an elevating arm, 9 is a proximity switch as a detection device, and 10 is an elevating arm winding device. An upper device, 11 is a limit switch for limiting the upward movement of the film unwinding mechanism, 12 is an engaging element constituted by the following 13 and 14, 13 is a tubular body, 13a is a flange of a tubular body, 14 is a weighted body, Reference numeral 14a is a cone-shaped collar, and 15 is a detection rod.

In the first embodiment, as shown in FIG. 2A, the holding plate 7 and the elevating arm 8 of the device 6 for holding the object to be packaged have the collar 13a.
A cylindrical body 13 with a collar and a collar 14a that engages with the collar 13a, and is connected by an engagement element 12 that includes a weight-shaped body 14 slidably fitted to the inner periphery of the collar 13a and the bottom thereof. Has been done. That is, the tubular body 13 of the engaging element 12 is pressed by the pressing plate 7.
Further, the weight bodies 14 are screwed to the elevating arms 8. Further, a proximity switch 9 is attached to the tip of the elevating arm 8 as a detection device for detecting the state in which the holding plate 7 presses the upper surface of the packaged object 5, and the pressing plate 7 further presses the upper surface of the packaged object. At this time, a detection rod 15 for operating the proximity switch 9 is provided. That is, the lower end of the detection rod 15 is in contact with the upper surface of the pressing plate 7, and the upper end of the detection rod 15 is slidably mounted so as to penetrate the weight body 14 and reach the vicinity of the proximity switch 9.

In the stretch wrapping machine of the first embodiment, the article to be packaged 5
After placing the table on the rotary table 2, the device 6 for pressing the object to be packed 6
The elevating arm 8 starts to descend. As shown in FIG. 2b, the pressing plate 7 stops descending when it comes into contact with the upper surface of the article to be packaged 5, but the elevating arm 8 continues to descend. At this time, since the lower end of the detection rod 15 is in contact with the upper surface of the pressing plate 7, the lowering is stopped, and accordingly, the upper end of the detection rod 15 approaches the gradually lowering proximity switch 9 together with the elevating arm 8, and the proximity switch is detected. When the area is reached, the proximity switch 9 is operated to stop the lowering of the elevating arm 8. At this time, there is a distance between the tapered portion of the weight body and the inner circumference of the collar 13a of the tubular body 13 by the distance t shown in FIG. 2b. In this way, the pressing plate 7 is released from being supported by the elevating arm 8 and placed on the upper surface of the article to be packaged 5 along the upper surface. If the upper surface of the article to be packaged is inclined, the holding plate 7 is also inclined and placed along the upper surface. When the pressing plate 7 is placed on the upper surface of the article 5 to be packaged, it is not only tiltable but also horizontally movable within a distance t shown in FIG. During the rotation of 2, the object to be packaged 5 can freely rotate around the rotation axis of the rotary table 2. The stretch wrapping process itself is the same as that of the known stretch wrapping machine, and therefore the description thereof is omitted. After the packaging process is completed, that is, after the rotary table 2 is stopped at a predetermined position, when the object-to-be-packaged pressing device 6 starts to rise, the weight-shaped body 14 of the engaging element 12 also rises, and the collar 14a has a tubular body. It engages with the collar 13 a of 13. During this time,
The upper end of the detection rod 15 also leaves the detection area of the proximity switch 9. Then, the holding plate 7 is lifted up by the engagement element 12 and separated from the upper surface of the article to be packaged 5.

FIG. 3 shows another embodiment of the present invention (hereinafter referred to as the second embodiment).
FIG. 6 is a partial cross-sectional view of the holding plate mounting portion of the stretch wrapping machine of FIG. The symbols in the figures have the same meanings as in FIGS. 1 and 2.

In the second embodiment, the weight body 14 of the engaging element 12 is screwed to the pressing plate 7, and the tubular body 13 is screwed to the elevating arm 8. Further, the proximity switch 9 as a detection device is fixed to the upper surface of the weight body 14 and is not provided with a detection rod, and when the up-and-down arm 8 approaches, it detects and operates. Since the operation itself of the package pressing device 6 is the same as that of the first embodiment, the detailed description is omitted.

FIG. 4 is a partial perspective view of a holding plate attaching portion of a device for holding an object to be packed of a stretch wrapping machine according to a third embodiment of the present invention, and symbols in the drawing have the same meanings as in FIGS. Have.
In the third embodiment, the holding plate 7 has a quadrangular shape, and the weight body 14 of the engaging element 12 has a circular cross section at its top and a quadrangular cross section at its bottom. In addition, the tubular body 13
The inner circumference of the collar 13a is also quadrangular so as to be slidably fitted with the bottom portion of the weight body 14.

Generally, when the object to be packaged 5 is a collection of small items, the pressing plate 7 is formed into a quadrangle so that the corners of the object to be packaged can be pressed. However, since the pressing plate 7 is rotatable, when the packaging process is completed, Even if the rotary table 2 is accurately stopped at the position before the start of rotation, the rectangular holding plate 7 may slip slightly from the upper surface of the article to be packaged 5 during rotation, for example. In the third embodiment, the bottom of the weight body 14 has a quadrangular cross section, and the inner periphery of the flange 13a of the tubular body 13 is also quadrangular so that the bottom of the weight body 14 can be slidably fitted. When the packaging process is completed and the lifting arm 8 is lifted to lift the holding plate 7,
The bottom portion of the weight body 14 and the inner circumference of the collar 13a of the tubular body 13 are fitted to each other, and at this time, some displacement of the position of the holding plate 7 is automatically corrected. Since the other points are the same as those in the first embodiment, detailed description will be omitted.

Instead of the proximity switch 9 as the detection device,
For example, a limit switch or a beam switch having an appropriate function may be used. Further, the present invention is applicable not only to the spiral type stretch wrapping machine but also to the full web type stretch wrapping machine, and also a semi-automatic machine for automatically moving the wrapping material. In addition, mounting the packaging film on the wrapping material. It is also applicable to a fully automatic machine that automates a series of processes such as cutting the film and fixing the cut end.

[Effect of device]

In the stretch wrapping machine of the present invention, the holding plate 7 and the elevating arm 8 of the device 6 for holding objects to be wrapped have the tubular body 13 with the collar 13a and the collar 14a engaging with the collar 13a. The inner periphery of 13a and the bottom thereof are connected by an engagement element 12 made of a weight body 14 which is slidably fitted. When the holding plate 7 pushes the upper surface of the article to be packaged 5, the tubular body 13 There is a distance t between the inner surface of the collar 13a and the tapered portion of the weight body 14, and the holding plate 7 is released from the support by the elevating arm 8 during the packaging process, and is inclined along the upper surface of the article 5 to be packaged. Even if the center of the holding plate 7 and the rotary shaft of the rotary table 2 are slightly deviated from each other, they are rotated together with the object to be packaged 5 about the rotary shaft of the rotary table 2 and accordingly the press plate 7 is rotated.
The center of the circle moves circularly with a small radius on the top surface of the object to be packaged 5,
It is possible to avoid severe wear of the fixing screws on the holding plate and / or the lifting arm, and to displace the film or the paperboard covered on the upper surface of the package, and the practical effect is great.

[Brief description of drawings]

FIG. 1 is a side view of a stretch wrapping machine according to a first embodiment of the present invention, and FIG. 2 is a partial cross-sectional view of a holding plate attachment portion of a package holding device of the stretch wrapping machine of FIG. FIG. A shows a state where the pressing plate does not press the upper surface of the packaged object, and FIG. 2b shows a state where the pressing plate presses it. FIG. 3 is a partial cross-sectional view of the holding plate mounting portion of the stretch wrapping machine according to the second embodiment of the present invention, showing a state in which the holding plate does not press the upper surface of the package. FIG. 4 is a partial perspective view of a holding plate mounting portion of a stretch wrapping machine according to a third embodiment of the present invention. FIG. 5 is a side view of a conventional stretch wrapping machine, and FIG. 6 is a partial cross-sectional view of a holding plate mounting portion of the stretch wrapping machine of FIG.
FIG. 7 is a partial sectional view of a holding plate mounting portion of a conventional stretch wrapping machine different from FIGS. 5 and 6. Symbols in the figure 1 ... Base frame, 2 ... Rotary table, 3 ... Film winding, 4 ... Film unwinding mechanism,
5 ... Packaged object, 6 ... Packaged object pressing device, 7 ... Holding plate, 8 ... Elevating arm, 9 ... Proximity switch as a detection device for limiting the lowering of the elevating arm 8; Arm hoisting device, 11 ... Limit switch for limiting the ascending of the film unwinding mechanism, 12 ... Engagement member, 13 ... Cylindrical body, 13a ... Cylindrical collar, 14 ... Weight body, 14a
...... Cylinder-shaped collar, 15 ...... Detection rod, 21 ...... Shaft,
22 ... screw, 23 ... spring, 24 ... steel ball, 2
5: A limit switch that limits the lowering of the lifting arm.

Claims (1)

[Scope of utility model registration request] 1. A rotary table 2 on which an article to be packaged 5 is placed,
Holding plate 7 for pressing the upper surface of the packaged object on the rotary table
Further, the object-to-be-packaged pressing device 6 including the elevating arm 8 for supporting the pressing plate and the film winding device 3 for packaging are vertically aligned with respect to the rotary table, and the film film winding device is held so that the film film winding can be rewound. In the stretch wrapping machine mainly including the film unwinding mechanism 4, a holding plate 7 and a lifting arm 8 are provided.
And a cylindrical body 13 with a collar 13a, and a collar 14a engaging with the collar 13a, and a weight-shaped body 14 slidably fitted at the inner periphery of the collar 13a and the bottom thereof. Child 12
And the pressing plate 7 comes into contact with the upper surface of the article 5 to be packaged, and the pressing plate 7 is packaged between the inner circumference of the collar 13a of the tubular body 13 and the tapered portion of the weight body 14. Detecting that the elevating arm 8 has descended to a position at which a sufficient distance t is formed so that it can be tilted along the upper surface of the article 5 and rotatable about the rotation axis of the packaged object, A stretch wrapping machine comprising a detection device 9 for stopping an arm.