JPS6112564A - Detecting method of film residual quantity - Google Patents

Abstract

PURPOSE:To detect a film residual quantity so accurately as well as to aim at improvements in operatability and productivity, by letting a radial, metallic timing plate installed on a bobbin shaft measure a speed of rotation with measurement of a pulse signal produced in time of acting on a proximity sensor. CONSTITUTION:A timing plate 16 detecting a speed of rotation of a bobbin 15 aims at the improvement of accuracy in a way of installing more than siz pieces of a metallic vane 16a in a radial manner. And, in proportion as a film 14 used as being rewound at a constant speed, a winding diameter of a residual film becomes small by degrees, while a speed of rotation in the timing plate 16 making a driving shaft 11 in common with the bobbin 15 gradually increases as well. Here, a relationship between the speed of rotation of the timing plate 16 and a residual film winding quantity is grasped in advance, and when reaching to the specified speed, the speed is detected, selecting it to a device having an unconsumed bobbin being set up separately. Therefore, a lowering of operatability and productivity based on an error in the film residual quantity is solvable.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the use of a thin ribbon-like film wound around a bobbin, which is unwound at a predetermined speed. This article relates to a method for measuring the amount of film remaining.

[Background of the invention]

In general, when manufacturing metal cans, especially adhesive cans in which the side seams of the can body are joined using a thin film-like adhesive tape with a width of about fu, a film-like adhesive tape wound around a bobbin is used. It is used to rewind at a constant speed. When the adhesive tape is consumed and the remaining amount reaches a set value, the system automatically switches to another unconsumed bobbin winding film to continuously supply the film.

[Conventional technology]

Conventionally, as a means of detecting the remaining amount of film, a transmission beam sensor (1) is used to detect when the thickness of the wound film layer (2) has decreased to a predetermined value, as shown in Figure i-3. When the film layer (2) falls below a predetermined value, other unconsumed bobbin windings are automatically switched to film to continuously supply film.

With such means, if the film wound around the bobbin is unevenly wound, the thickness of the film layer will vary depending on the position of the width of the bobbin, and the film itself will be thin, resulting in problems with accuracy. Furthermore, if the film is easily transmissive to light, the measurement error will be large, and the bobbin may be switched to another bobbin with a large amount of film remaining, or conversely, the film may be consumed before the switching operation is performed. However, there was a serious problem in that the film could not be continuously sent to the post-process, and the production of adhesive cans was interrupted, resulting in a decrease in workability and productivity.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and it solves the problems of the prior art by simple and rational means, and eliminates the error in the remaining amount of film and the complete cost of film. It aims to improve workability and productivity by providing a method for detecting amounts.

[Means for Solving the Problems] In order to solve the above-mentioned problems of the prior art, the present invention unwinds and consumes a thin transparent film wound around a bobbin of a predetermined diameter at a constant speed. In this case, the rotational speed of the bobbin is determined by a pulse generated when the metal blades of a timing plate, which is attached coaxially with the bobbin and is provided with at least six gear-shaped metal blades radially, act on a proximity sensor. The present invention is characterized in that the rotational speed is measured by measuring the signal, the amount of film consumed on the bobbin is measured based on this value, and the remaining amount of film is detected.

〔Example〕

Figures 1 and 12 show the apparatus used to carry out the method of the present invention, Figure 17 is a partially cutaway front view, and Figure 12 is a front view of a timing plate having gear-like metal vanes. >Explaining the schematic structure of the device with regard to Figure 1:
αυ is a rotating shaft mounted on bearing a3 installed on the machine frame α,
A bobbin αυ, which is made by winding multiple layers of a transparent film αυ about an inch in width in the form of a spool, is replaceably fixed to the rotating shaft aυ.

A timing plate α0 having six or more gear-shaped metal blades (ltα) radially provided on the outer periphery is fixed to one end of the rotating shaft (11), and a timing plate α0 is fixed to the machine frame α2. A proximity sensor OIS is provided with a slit (1?+) through which a metal blade (iag) of the IG passes.A metal blade (/) through which the proximity sensor α smoke passes is provided.
The pulse signal emitted by 4α) is quantified by a numerical conversion mechanism (not shown), and the rotational speed is thereby measured.

As the film α is rewound at a constant speed and used, the winding diameter of the remaining film gradually becomes smaller. The rotational speed of the timing plate αe, which shares the same rotational axis (11) as the bobbin 09, also gradually increases. Understand the relationship between the rotation speed of the timing plate (16) and the amount of remaining film wrapped in advance, and when the rotation speed reaches a predetermined value, detect that speed and remove the unused bobbin installed separately. This is to switch to a device that has.

The timing plate 0e for detecting the rotational speed of the bobbin α→ has metal blades (16α) arranged radially around it, and the number of metal blades (1t, α) is 6 or more pieces. It has been experimentally determined that if there are fewer than six pieces, it would be difficult to accurately detect the rotational speed using a combination of a timing plate and a proximity sensor, so the number is specified as six pieces or more.

Further, as the proximity sensor, conventionally known beam sensors, magnetic sensors, electrostatic sensors, proximity switches, etc. can be used.

〔effect〕

As described above, according to the present invention, there are problems with the prior art, specifically, uneven winding of the film wound around the bobbin, transparency of the film, and furthermore, the amount of remaining film due to the setting error of the detector. It has excellent features such as excessive amount of film, all the film is consumed before the switching operation, interruption of post-processes, and resulting reduction in workability and productivity, etc., and the detection method is simple. has.

[Brief explanation of the drawing]

Figure 7 is a partially cutaway front view showing an embodiment of an apparatus for carrying out the method of the present invention, Figure 2 is a front view of a timing plate, and Figure 3 is an explanatory diagram of a prior art device. Ql)...rotating axis, θ...machine frame, α...bearing,
04)...Film, a9...Bobbin, θ0...
Timing plate, (μα)...metal blade, αD・
...Slit, α ... Proximity sensor.

Claims (1)

[Claims] (a) When a thin transparent film wound around a bobbin of a predetermined diameter is rewound and consumed at a constant speed, (b) The rotational speed of the bobbin is adjusted to be coaxial with the bobbin. The rotational speed is measured by measuring the pulse signal generated when the metal blades of the timing plate, which is attached to the top and has at least six pieces of gear-shaped metal blades arranged radially, act on the proximity sensor, and this value is measured. A method for detecting a remaining amount of film, characterized by measuring the amount of film consumed in a bobbin and detecting the remaining amount of film.