JP2595270Y2 - Β-ray gravimeter for paper machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a beta-ray gravimeter for a paper machine which can be installed in a paper machine and detect whether or not a piece of stock caused by a paper break exists between the upper and lower heads. It is.

[0002]

2. Description of the Related Art Generally, various measuring devices for measuring, controlling, or monitoring the basis weight, moisture, thickness, ash, color, etc. of a stock sheet are installed downstream of a dryer part of a paper machine. Have been. In such various measuring instruments,
As a measuring instrument for continuously measuring the grammage of a stock sheet during papermaking, a β-ray gravimeter using a radioisotope such as krypton 85 or promesium 147 as a radiation source is frequently used.

The beta-ray gravimeter generally comprises an upper head and a lower head, and beta rays emitted from one of the heads travel between the upper and lower heads while a stock sheet passes through between the upper and lower heads. Since the absorbed amount changes in accordance with the basis weight of the stock material being fed, the device detects the basis weight of the running stock material from the change, but the gap between the upper and lower heads is β Although it depends on the manufacturer of the line gravimeter, for example, 4 mm from the viewpoint of preventing leakage of β-rays to the outside
It is usually very narrow, ~ 11.5 mm.

[0004] As a result, if the paper breaks in the paper machine during use of the β-ray grammage meter, the head of the β-ray gravimeter retreats to the origin position which is off the running stock sheet. In this case, the broken sheet end often passes between the upper and lower heads while the head is being retracted, and the broken sheet end is caught in the gap between the upper and lower heads when passing through the head because tension is not applied to the broken sheet end. Often clog between the upper and lower heads. After such a paper breakage occurs, if the paper is re-passed and the β-ray grammage meter is operated in a state in which the paper material pieces are clogged between the upper and lower heads, the paper jams between the upper and lower heads when the head enters the paper material sheet end. In some cases, the paper material pieces that come in contact with the running paper material sheet may cause the paper material sheet that has passed through the paper to break again, and even if the paper material does not break, the paper material pieces that are jammed between the upper and lower heads It touches the running stock sheet and damages the stock sheet. Further, in recent years, the β-ray gravimeter is often juxtaposed with each sensor of the measuring device for measuring moisture, thickness, ash, color, etc., but there is a piece of stock between the upper and lower heads. Paper passing again with
The operation of the linear gravimeter would cause erroneous measurement of each of these sensors.

In order to solve the above-mentioned problems, conventionally, when a paper break occurs in a paper machine and the head of the β-ray gravimeter is retracted to an origin position which is off the stock sheet on which the head is running, The operator checks whether or not the gap between the upper and lower heads is clogged with a piece of stock. This operation is very troublesome for the following reasons. 1) A radioisotope is used for the gravimetric sensor of the head of the beta-ray gravimeter, and a certain area where the head source shutter is open is specified as a control area according to the Radiation Prevention Control Regulation. The work is complicated because the assigned worker must work while observing the observable items. 2) In the state where the head of the beta-ray gravimeter is retracted to the origin position deviated from the running stock sheet, the source shutter of the head is closed, but there is a risk of beta-ray leakage, It is desirable to avoid work near this as much as possible. 3) Since the origin position where the head of the β-ray gravimeter retreats is on the drive side opposite to the operation side and the opposite side of the stock sheet, the operator moves from the operation side to the drive side every time a paper break occurs. When the paper is exhausted, the user is busy with other work associated with the paper exhaustion, which makes it difficult to perform quick inspection work. 4) The origin position where the head of the β-ray gravimeter retreats is
Usually, it is not a place where workers work in the vicinity, so the working environment is poor in terms of lighting and the like, and since the gap between the upper and lower heads of the β-ray grammage meter is narrow as described above, The task of checking whether a gap is clogged with stock is challenging.

As described above, there are various obstacles in checking whether or not a piece of stock is clogged in the gap between the upper and lower heads of the beta-ray grammage meter. If a piece of stock is clogged between the upper and lower heads when operating the beta-ray gravimeter, the piece of stock will come into contact with the running stock sheet and cause the paper sheet to break again at the angled stock sheet. Even if the paper does not run out, the clogged paper pieces between the upper and lower heads may contact the running paper sheet and damage the paper sheet. The operation of checking whether or not a piece of stock is clogged in the gap is a task that must be performed every time a paper break occurs, which is a heavy burden on the operator.

[0007]

[Problem to be Solved by the Invention] In the present invention, the work of checking whether or not a piece of stock is clogged in the gap between the upper and lower heads of the β-ray gravimeter, which has been a heavy burden on the operator, has a paper breakage. Rather than performing it every time, a β-ray gravimeter for paper machine that allows the operator to detect that a piece of stock is clogged in the gap between the upper and lower heads of the β-ray gravimeter on the operation side of the paper machine. Another object of the present invention is to make it difficult for paper material pieces to be clogged in a gap between the upper and lower heads of the β-ray gravimeter for a paper machine.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, generally, the size of stock pieces clogged in the gap between the upper and lower heads of the β-ray gravimeter is relatively large. Since there is no completely flat state between the upper and lower heads, there is a β-ray gravimeter between the origin position where the head of the β-ray gravimeter retreats and the edge position of the running stock sheet. The light-emitting source and the light-receiving element are installed facing each other so as to sandwich the portion where the head passes and the height thereof is located between the upper and lower heads of the β-ray gravimeter, If the light emitted from the light-emitting source is not received by the light-receiving element when the head retreats to the origin position, an alarm device that notifies that the paper pieces are clogged in the gap between the upper and lower heads of the β-ray grammage meter By connecting the light receiving element to the By investigation can be detected that the waiting is for a paper machine β Sentsubo meter according to the present invention was completed. Further, an air ejection nozzle is installed in parallel with at least one of the installation positions of the light emitting source and the light receiving element.
If air of about kg / cm ² is ejected between the upper and lower heads of the β-ray gravimeter that retreats to the origin position, it is a piece of paper clogged in the gap between the upper and lower heads of the β-ray gravimeter. It has also been found that a piece of stock in a state of being placed can be blown off and removed from between the upper and lower heads of the beta-ray grammage meter.

Hereinafter, a β for a paper machine according to the present invention will be described with reference to the drawings.
The linear gravimeter will be described in detail. FIG. 1 is a perspective view schematically showing a β-ray basis weight meter for a paper machine according to the present invention, and FIG. 2 is a positional relationship between an upper and lower head, a light emitting source, and a light receiving element in the β-ray basis weight meter for a paper machine according to the present invention. FIG. 3 is a side view showing the positional relationship between the upper and lower heads and the air ejection nozzle in the β-ray gravimeter for a paper machine according to the present invention, and FIG. 4 is a β-ray for the paper machine according to the present invention. FIG. 3 is an explanatory plan view showing a positional relationship among a light emitting source, a light receiving element, and an air ejection nozzle in the gravimeter.

In the drawings, reference numeral 1 denotes a moving mechanism for moving the upper head 2 and the lower head 3 of the β-ray grammage meter in a direction orthogonal to the flow direction of the paper sheet S made by the paper machine. A known reel frame provided with upper and lower heads 2,
3 are simultaneously moved at the same speed. Reference numerals 4 and 5 denote the upper and lower heads 2 and 3 of the β-ray gravimeter between the origin position where the upper and lower heads 2 and 3 of the β-ray gravimeter retract and the edge position of the running stock sheet S. Between the parts and the height is β
A light-emitting source and a light-receiving element that are installed facing each other so as to be located between the upper and lower heads 2 and 3 of the linear grammage;
If the light emitted from the light emitting source 4 is not received by the light receiving element 5, an alarm device (not shown) for notifying that the space between the upper and lower heads 2 and 3 of the β-ray grammage is clogged with the paper material pieces. ) Is connected to the light receiving element 5.

Reference numeral 6 designates a space between the upper and lower heads 2 and 3 of the β-ray gravimeter which is installed in parallel with at least one of the light emitting source 4 and the light receiving element 5 and retracts to the origin position. An air ejection nozzle to be ejected. The air pressure ejected from the air ejection nozzle 6 is 2 to 3
About kg / cm ² is sufficient. The position of the air ejection nozzle 6 is closer to the edge position of the running stock sheet S than the position of the light emitting source 4 and the light receiving element 5. 3 is blown off by the air jetted from the air jet nozzle 6, and then the light emitting source 4 and the light receiving element 5 are used to fill the gap between the upper and lower heads 2 and 3 of the β-ray grammage meter. Since it is detected whether or not the stock is clogged, the detection accuracy is preferably improved.

[0012]

In the process of measuring the basis weight of the stock sheet S being produced by the paper machine using the β-ray basis weight meter for the paper machine according to the present invention having the above structure, paper breakage occurs in the paper machine. Then, the upper and lower heads of the β-ray grammage meter 2,
Reference numeral 3 simultaneously retreats to the origin position deviated from the stock sheet S running on the reel frame 1 at the same speed. In this case, particularly when the sheet trailing end passes through between the heads while the upper and lower heads 2 and 3 are retreating, the gap between the upper and lower heads 2 and 3 is caught, and a phenomenon that the paper material pieces are jammed easily occurs. The distance between the origin position where the upper and lower heads 2 and 3 of the gravimeter retreat and the edge position of the running stock sheet S is β.
The light-emitting source 4 and the light-receiving element 5 are opposed to each other so as to sandwich a portion through which the upper and lower heads 2 and 3 of the linear grammage pass, and to be positioned between the upper and lower heads 2 and 3 of the β-ray gravimeter. Is installed, so that when a stock piece is clogged between the upper and lower heads 2, 3, the stock sheet S on which the upper and lower heads 2, 3 are running
It is detected that the light emitted from the light emitting source 4 has not been received by the light receiving element 5 while being retracted to a more deviated origin position, and a stock is clogged between the upper and lower heads 2 and 3. Is automatically detected and transmitted to the alarm device. As a result, the operator is automatically in the operating position and can determine whether or not a piece of stock is clogged between the upper and lower heads 2 and 3 of the β-ray grammage meter. This eliminates the need to move to the drive side to check whether a piece of stock is clogged between the upper and lower heads 2 and 3 of the gravimeter.

[0013] An air jet is provided adjacent to at least one of the light-emitting source 4 and the light-receiving element 5 for jetting air between the upper and lower heads 2 and 3 of the β-ray gravimeter retracted to the origin position. When the nozzle 6 is further provided, when a paper break occurs in the paper machine, the stock material that has been slightly caught in the gap between the upper and lower heads 2 and 3 can be blown off by the ejected air. It is possible to further reduce the occurrence of the phenomenon that the stock is clogged between the upper and lower heads 2 and 3 of the meter.

In this case, when the air ejection nozzle 6 is provided adjacent to the edge position side of the stock sheet S running from the installation position of the light emitting source 4 and / or the light receiving element 5,
By the time the upper and lower heads 2 and 3 of the β-ray gravimeter retracted to the origin position reach the installation position between the light emitting source 4 and the light receiving element 5, a piece of stock that has been slightly caught in the gap between the upper and lower heads 2 and 3 Since it has been blown off, the phenomenon that the material pieces have clogged between the upper and lower heads 2 and 3 of the β-ray gravimeter has occurred and the clogged material pieces cannot be easily removed. It can be detected.

[0015]

As described above, the beta-ray gravimeter for a paper machine according to the present invention is applied to a running paper sheet that has been re-passed after a piece of paper is jammed between the upper and lower heads of the beta-ray grammage. In order to prevent the occurrence of paper breakage or damage, the operator needs to check the gap between the upper and lower heads for paper fragments every time a paper break occurs. This effect is greatly reduced because the work burden of the operator is significantly reduced, and when an air ejection nozzle is further installed, the lightly caught pieces of stock are blown off in the gap between the upper and lower heads, The benefits that contribute to the papermaking sector are huge.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically illustrating a β-ray gravimeter for a paper machine according to the present invention.

FIG. 2 is a side view showing the positional relationship between the upper and lower heads, the light emitting source, and the light receiving element in the β-ray gravimeter for a paper machine according to the present invention.

FIG. 3 is a side view showing the positional relationship between the upper and lower heads and the air ejection nozzle in the β-ray gravimeter for a paper machine according to the present invention.

FIG. 4 is an explanatory plan view showing a positional relationship among a light emitting source, a light receiving element, and an air ejection nozzle in the β-ray basis weight meter for a paper machine according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reel frame 2 Upper head of beta-ray grammage meter 3 Lower head of beta-ray grammage meter 4 Light emitting source 5 Light receiving element 6 Air ejection nozzle S Paper material sheet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) D21F 7/06 G01B 11/00 G01B 15/02 G01G 17/02 G01V 8/12

Claims (3)

(57) [Scope of request for utility model registration] An upper / lower head of a beta-ray grammage is located between an origin position where an upper / lower head (2, 3) of a beta-ray gravimeter retreats and an edge position of a running stock sheet (S). The upper and lower heads of the beta-ray gravimeter sandwich the part where (2, 3) passes and whose height is
Light-emitting sources facing each other so as to be located between (2, 3)
(4) and the light receiving element (5) are installed, and the light emitting source is used when the upper and lower heads (2, 3) of the β-ray gravimeter retreat to the origin position.
When the light projected from (4) is not received by the light receiving element (5), an alarm device for notifying that the paper material is clogged in the gap between the upper and lower heads (2, 3) of the β-ray grammage meter. Light receiving element
(5) A β-ray gravimeter for a paper machine, which is connected. 2. A β-ray gravimeter, which is provided in parallel with at least one of a light-emitting source (4) and a light-receiving element (5) and retracted to an origin position, between upper and lower heads (2, 3). An air jet nozzle (6) for jetting air is provided.
2. A β-ray gravimeter for a paper machine according to the item 1. 3. An air jet nozzle (6) is provided adjacent to an edge position side of a stock sheet (S) running from a position where a light emitting source (4) and / or a light receiving element (5) is installed. 3. The β-ray gravimeter for a paper machine according to 2.