JP2000268817A - Electrode sheet cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode sheet cutting device assuring a proper manufacture and quality control and capable of performing cutting-off of an electrode sheet with a good yield. SOLUTION: This electrode sheet cutting device is composed of an automatic feeding mechanism 1 to pay off intermittently an electrode sheet wound in a hoop shape and feed automatically at a constant speed, a sensing part 2 to sense existence of flaw on the sheet being fed, a cutting mechanism 3 installed adjacent to the sensing part 2 in its downstream and to cut off the sheet into the specified dimension, and an unacceptable piece discharging mechanism 4 which is installed downstream of the cutting mechanism 3, works in response to the motion of cutting-off, changes over the automatic feeding mechanism 1 intermittently (1d), and discharges cut pieces judged as including flaw etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode sheet cutting apparatus, and more particularly, to an electrode sheet cutting apparatus having a mechanism for selectively discharging cut separation pieces including defective portions by automatic fixed size cut separation. It relates to a cutting device.

[0002]

2. Description of the Related Art In recent years, with the promotion of cordless, high-performance, and compact and lightweight electronic devices such as portable telephones and portable notebook personal computers (PCs), the main power supply of these electronic devices has been increased. There is a demand for higher performance batteries. As a main power source for these electronic devices, nickel-metal hydride secondary batteries or lithium secondary batteries capable of achieving higher performance and higher capacity have been put into practical use.

[0003] The nickel-hydrogen secondary battery and the like are generally wound or laminated by interposing a separator carrying an electrolytic solution (electrolyte) between a band-shaped (sheet-shaped) positive electrode and a negative electrode, and winding or laminating the electrode. A group (power generation element portion) is formed, and this electrode group is liquid-tightly sealed in a battery outer container. Here, an electrode group (electrode element portion) of the secondary battery, for example, an electrode group of a nickel-metal hydride secondary battery generally includes a positive electrode active material layer containing a nickel compound in a belt-shaped (sheet-shaped) current collector. The provided one is configured as a positive electrode sheet, and the one provided with a negative electrode active material layer including a hydrogen storage alloy having a CaCu ₅ type crystal structure on a belt-shaped current collector is also configured as a negative electrode sheet.

[0004] Examples of the sheet-like current collector include a sheet-like metal foil such as aluminum, copper, nickel, titanium, and stainless steel, or a sheet-like wire mesh or sheet-like porous thin plate such as expanded metal. Can be The form of these sheet-like current collectors is
It is a non-porous sheet, a perforated sheet, a net-like (net-like) sheet, etc., and its thickness is about 20 to 50 μm.

The above-mentioned electrode sheet is prepared by preparing an electrode active material corresponding to a sheet-like current collector into a paste or gel and applying the paste or gel electrode active material to the surface of the current collector. , Dried, and further subjected to processing such as pressure bonding, and then cut and separated into desired dimensions. here,
The filling amount of the electrode active material in the electrode sheet (the amount of the electrode active material to be supported) and the homogeneity are determined by the electrode group composed of these electrode sheets, or, in other words, by increasing the capacity or improving the volume efficiency of the battery. Depends.

Therefore, in the electrode sheet formed in a long strip shape, holes penetrating in the thickness direction at substantially constant intervals are formed, and the state of the inner wall surface of the formed holes is observed and evaluated. For example, quality control of electrode sheets is performed. Further, the cutting and separation of the electrode sheet is usually performed intermittently unwinding the electrode sheet wound in a hoop shape at a constant speed and without automatic feeding. The electrode sheet ends are attached and connected with cellophane tape to make them longer.

[0007]

The cutting and separating pieces including the hole formation for the quality control of the electrode sheet and the sticking connection between the electrode sheet edges from the viewpoint of continuous workability cannot be used for the construction of the electrode group. That is, when the cut and separated piece includes at least one of the perforated hole and the sticking connection part, it is necessary to classify it as a defective product that can be used in the configuration of the electrode group as a defective product.

In the conventional cutting / separating method using automatic feeding, the position of a detecting unit for detecting the presence / absence of a defect (good / defective) is arbitrary (not specified) with respect to the cutting mechanism.
The detection unit detects the presence of a defect, and upon detecting the defect (defective), the timer of the defective product discharging unit is operated, and the defective product is discharged from the automatic feeding mechanism. In this method, when the detecting unit detects a defective product regardless of whether the automatic feed mechanism is driven or stopped, the timer of the defective product discharging unit operates in response to the detection. Depending on the timing, two cut pieces may be ejected from the automatic feed mechanism as defective.

That is, due to a slight change in the installation position of the detection unit or a slight displacement of the installation position of the detection unit, the timing of the timer operation is shifted, and both defective (defective) and non-defective products are discharged. Things also happen.
Such a risk of malfunction not only impairs the manufacturing control of the electrode sheet, but also causes a reduction in the yield of the electrode sheet and an increase in the cost of the electrode sheet.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a cutting apparatus capable of performing appropriate production and quality control and cutting and separating an electrode sheet with a high yield.

[0011]

According to a first aspect of the present invention, there is provided an automatic feeding mechanism for intermittently unwinding and automatically feeding an electrode sheet wound in a hoop shape at a constant speed, and the automatically fed electrode sheet. A detecting unit that detects the presence or absence of a defect, a cutting mechanism that is arranged adjacent to the downstream side of the detecting unit and cuts and separates the electrode sheet to a predetermined size, and a cutting and separating operation that is arranged downstream of the cutting mechanism. And a defective product discharging mechanism for intermittently switching the automatic feed mechanism and discharging the cut and separated pieces determined to be defective.

According to the first aspect of the present invention, the electrode sheet cutting device includes, for example, an automatic feeding mechanism including a plurality of sets of endless belts arranged in a line in a certain direction;
A configuration having a cutting mechanism and a defective product discharging mechanism disposed between the endless belts is adopted. The cutting mechanism is, for example, a punching die that performs an intermittent punching operation. Further, a detection unit which is disposed adjacent to and upstream of the cutting mechanism and detects the presence or absence of a defect (perforation hole, connection portion, etc.) in the automatically fed electrode sheet is, for example, a light reflection type or a light transmission type. When a defect is detected, the information (output signal) is input to the defective product discharge unit, the switching unit is opened, and the defect is discharged from the feed mechanism.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to FIG.

FIG. 1 is a block diagram showing a schematic configuration of an electrode sheet cutting apparatus according to an embodiment. In FIG. 1, 1
Is an automatic feed mechanism that intermittently unwinds and automatically feeds the electrode sheet wound in a hoop shape at a constant speed, 2 is a detection unit that detects the presence or absence of a defect in the automatically fed electrode sheet,
Reference numeral 3 denotes a cutting mechanism which is disposed adjacent to the downstream side of the detection unit 2 and cuts and separates the electrode sheet into a predetermined size. Reference numeral 4 denotes a cutting mechanism which is disposed downstream of the cutting mechanism 3 and responds to the operation of cutting and separating. This is a defective product discharging mechanism for selectively switching the automatic feeding mechanism and discharging the cut and separated pieces determined to be defective.

Here, the automatic feeding mechanism 1 comprises a first endless belt 1a which unwinds the electrode sheet and transfers it to the cutting mechanism 3 for cutting and separating the electrode sheet into a fixed size;
The cut and separated pieces cut and separated by the cutting mechanism are transferred,
A second endless belt 1b to be automatically fed, a third endless belt 1c to which cut and separated pieces are transferred and automatically fed from the second endless belt 1b, and a second endless belt 1b and a third endless belt Switching section 1d inserted between endless belt 1c and opening and closing between both belts 1b and 1c
It is composed of The switching unit 1d of the automatic feed mechanism 1 functions as a defective product discharging mechanism 4.

The detecting unit 2 for detecting the presence or absence of a defect in the electrode sheet automatically fed by the first endless type belt 1a adjacent to the upstream of the cutting mechanism 3 is, for example, a light reflection type.
Alternatively, it is a light transmission type detection element. Then, a defect area of the automatically fed electrode sheet, that is, a part including a perforated hole or a connection part is detected. If a defect is detected, the information (output signal) is output as a defective product. The switching unit 1d is opened by inputting to the unit 4, and the defective electrode sheet fragments are discharged from the automatic feeding mechanism 1.

Further, the cutting mechanism (for example, a punching die) 3 employs a configuration in which a pair of cutting blades 3a and 3b are arranged substantially parallel and opposed to each other in order to cut and separate the electrode sheet into a required size (length). The facing distance is generally set to such an extent that the required (predetermined) dimension of the electrode sheet is added to the diameter of the perforated hole.

Next, the operation of the electrode sheet cutting device will be described.

When an electrode sheet which is automatically and intermittently fed at a constant speed through the first endless belt 1a passes through the detecting section 2, the detecting section 2 detects the presence or absence of a defect in the electrode sheet. Subsequent to this detection, the sheet is transferred to a punching die (cutting mechanism) 3 and is cut to a predetermined size by intermittent driving of the punching die 3, and the cut and separated pieces are transferred to the second endless belt 1b. It is loaded and sent automatically.

In this process, the detecting unit 2 detects the presence of a defect, and cuts and separates the defect including the defective portion, and adjusts (at timing) the automatic feeding speed of the cut and separated piece by the second endless belt 1b. 2nd and 3rd endless belts
When the switching unit 1d inserted between 1b and 1c is opened, only the cut and separated pieces detected as having the defect are selectively discharged from the automatic feeding mechanism 1.

In other words, in the case of a cut and separated piece that has been detected as having no defect, the switching unit 1d always inserted between the second and third endless belts 1b and 1c is closed.
The sheet is transferred to the third endless type belt 1c and is supplied and stored in a non-illustrated good tray or the like.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention. For example, the automatic feed mechanism may be a transport system other than the endless belt,
The detecting unit and the cutting mechanism can be replaced with other effective means.

[0023]

According to the first aspect of the present invention, of the electrode sheets cut to a fixed size, only the electrode sheet cut pieces including defective portions such as perforated holes and connection tapes can be reliably and easily automated. Are selectively separated. That is, since highly reliable defective products can be selected and eliminated with good productivity and low cost, not only the yield of the electrode sheet can be improved, but also a large contribution can be made to the configuration of a highly reliable battery.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an electrode sheet cutting device according to an embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Automatic feed mechanism 1a ... 1st endless type belt 1b ... 2nd endless type belt 1c ... 3rd endless type belt 1d ... Switching part 2 ... Detection part 3 ... Cutting mechanism 3a, 3b Cutting blade 4 Defective product discharge mechanism

Claims (1)

[Claims] An automatic feeding mechanism for unwinding an electrode sheet wound in a hoop shape and automatically feeding the electrode sheet intermittently at a constant speed; a detecting unit for detecting the presence or absence of a defect in the automatically fed electrode sheet; A cutting mechanism arranged adjacent to the downstream side of the detection unit to cut and separate the electrode sheet into a predetermined size; and an automatic feed mechanism intermittently arranged downstream of the cutting mechanism and responsive to the cutting and separating operation. An electrode sheet cutting device, comprising: a defective product discharging mechanism for discharging the cut and separated pieces determined to be defective by switching between them.