JPH04320961A - Device for measuring physical property of paper - Google Patents

Abstract

PURPOSE:To enable physical properties such as a gas transmission rate and a surface smoothness of a paper to be measured easily without any troublesome operations. CONSTITUTION:An air discharge hole 20a of a lower pressure-welded body 20 is matched to a specified position of an upper pressure-welded body 19 by operating a switching motor. When a paper 14 is sandwiched by the upper pressured-welded body 19 and the lower pressure-welded body 20, an inner cylinder 18 pushes an internal air downward by a press force of 567 + or - 1.0g. This air passes throuqh the paper 14 and is discharged to the outside from the air discharge hole 20a. When air is discharged by 100cc. a light-emitting sensor 18a moves to a position facing a lower light-reception sensor 22 from a position facing an upper light-reception sensor 21. Time required for this move is measured. A value which is obtained by expressing it in sec is a gas transmission rate of the paper 14.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a paper property measuring device, and more specifically, the present invention relates to a device for measuring paper physical properties, and more particularly, to measuring the air permeability and surface smoothness of various papers used in office equipment such as electrophotographic copying machines and facsimiles, and other fields. The present invention relates to an improvement of a paper property measuring device for measuring the physical properties of paper.

0002

[Background Art] Conventionally, a paper property measuring device for measuring physical properties such as air permeability and surface smoothness of paper has an outer cylinder that extends vertically and the ability to freely slide up and down within this outer cylinder. An inner cylinder for air discharge, an upper press-contact member installed below the outer cylinder that allows the air in the inner cylinder to pass downward, and a physical property measurement paper provided below the upper press-contact member. A device equipped with a lower press-contacting body that can be held in between is known.

[0003] Such a paper property measuring device is used in the following manner. For example, when measuring the air permeability of paper, if the paper is sandwiched between an upper presser and a lower pressurizer,
The inner cylinder pushes the internal air downward with a constant pressure. This air passes through the paper from the upper press-contact body to the lower press-contact body, and is pushed out from the through hole provided in the lower press-contact body. Then, use a stopwatch to measure the time until 100 cc of air is pushed out. The value expressed in seconds is the air permeability of the paper.

0004

[Problems to be Solved by the Invention] However, in the paper physical property measuring device as described above, scales are attached to the inner cylinder and the outer cylinder, and a certain amount of air (for example, 100 cc) is discharged while observing these scales. A barometer was attached to measure the time it took for a certain amount of air to reach atmospheric pressure after a certain amount of air was exhausted. In this way, the operator must check the discharge of a certain amount of air using a scale or barometer.
The problem was that it was bothersome.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a paper physical property measuring device that can easily measure the physical properties of paper without complicated operations.

[0006]

[Means for Solving the Problems and Their Effects] The present invention comprises an outer cylinder extending vertically, an inner cylinder for air discharge that can freely slide up and down within the outer cylinder, and a lower part of the outer cylinder. an upper press-contact member that is installed in the inner cylinder and allows the air in the inner cylinder to pass downward; and a lower press-contact member that is provided below the upper press-contact member and can hold the physical property measurement paper between the upper press-contact member and the upper press-contact member. Prepare,
Furthermore, a light emitting sensor is provided on the upper part of the outer surface of the peripheral wall of the inner cylinder and emits light outward in a substantially horizontal direction, a protruding wall is provided in the outer cylinder in an upwardly protruding manner, and a luminescent sensor is provided on the projecting wall in a substantially horizontally inward direction and in a predetermined vertical direction. This paper property measuring device includes an upper light receiving sensor and a lower light receiving sensor that are spaced apart and receive light from a light emitting sensor.

That is, the paper physical property measuring device of the present invention includes a specific light emitting sensor provided on the outer surface of the peripheral wall of the inner cylinder.
This light emitting sensor emits light approximately horizontally outward,
Furthermore, a protruding wall is provided in the outer cylinder in an upwardly protruding manner, and an upper light receiving sensor and a lower light receiving sensor are provided on the projecting wall toward the inner side substantially horizontally and at a predetermined interval vertically, so that the light from the light emitting sensor is disposed. It is characterized in that the light is received by an upper light receiving sensor and a lower light receiving sensor.

The distance between the upper light receiving sensor and the lower light receiving sensor is such that when the inner cylinder pushes the internal air downward with a certain pressing force, a certain amount of air passes through the inside of the upper pressing body to the outside of the device. It is set equal to the distance that the inner cylinder moves before being pushed out. Then, the time from when the light emitted from the light emitting sensor is received by the upper light receiving sensor until it is received again by the lower light receiving sensor is measured.

This paper physical property measuring device measures physical properties such as air permeability and surface smoothness of various types of paper. Here, the air permeability of paper is a measure of the porous structure of the paper, and is expressed as the time required for a given volume of air to pass through a given area of the paper. The surface smoothness of paper is a measure of the smoothness of the surface of the paper. Along one surface of the paper sandwiched between a pair of pressing bodies, one volume of air flows outside through the gap between the pressing bodies and the paper. It is expressed as the time required for the leak to occur.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Note that this invention is not limited to the following examples.

In FIG. 1, an electrophotographic copying machine C incorporating a paper property measuring member 15 as a paper property measuring device includes a photosensitive drum 5, a developing unit 4 disposed near the photosensitive drum 5, and a developing unit 4 disposed near the photosensitive drum 5. , a transfer/separation unit 8 disposed near the photosensitive drum 5, and a heat roller 12 and a pressure roller 13 disposed downstream of the photosensitive drum 5 in the paper conveyance path.

Reference numeral 1 denotes a paper feed cassette in which a large number of copy sheets 14 of a predetermined size are stored. 2 is paper cassette 1
This is the primary paper feed roller located above the paper. Reference numerals 3 and 3 denote a pair of upper and lower secondary paper feed rollers (registration rollers) arranged downstream of the primary paper feed roller 2 in the paper conveyance path. 6 is an optical unit, 7 is a main charger, and 9 is a cleaning unit. 10 and 10 are a heat roller 12 and a pressure roller 13
These are a pair of upper and lower paper ejection rollers arranged on the downstream side of the paper transport path. 11 is a document table cover.

The paper air permeability measuring member 15 is provided between the primary paper feed roller 2 and the secondary paper feed rollers 3. As shown in FIGS. 2 to 4, this paper property measuring member 15 includes an outer cylinder 17 filled with a specified amount of light spindle oil 16, and an inner cylinder (piston) that can freely slide up and down inside the outer cylinder 17. ) 18, an upper press member 19 made of rubber and attached under the outer cylinder 17, and a lower press member 20 made of rubber that presses against the upper press member 19 via the paper 14.

The upper press member 19 is ring-shaped. As shown in FIG. 2, the lower pressing member 20 has a disk shape, and is provided with an inverted T-shaped air exhaust hole 20a that opens upward and in the left and right directions. This air exhaust hole 20a is
This is the point where the air permeability in step 4 is measured. In addition, the lower pressure contact body 2
On the upper surface of the sheet 14, a smoothness measuring section 20b, which is a part for measuring the surface smoothness of the paper 14, is provided avoiding the air exhaust hole 20a. The lower pressing member 20 is rotated around a vertical axis by a switching motor 23 provided near the lower pressing member 20 by meshing gears. As a result, either the air exhaust hole 20a or the smoothness measuring section 20b is aligned with a predetermined location on the upper press member 19.

A light emitting sensor 18a is mounted on the upper part of the peripheral wall of the inner cylinder 18.
is provided. Further, a protruding wall 17a that protrudes upward from the upper end of the outer cylinder 17 and is provided integrally with the outer cylinder 17 includes:
The upper light receiving sensor 21 faces the light emitting sensor 18a.
and a lower light receiving sensor 22 are attached. The distance between the upper light receiving sensor 21 and the lower light receiving sensor 22 is the distance required for the inner cylinder 18 to push out 100 cc of air inside when the inner cylinder 18 is pushed downward with a pressing force of 567±1.0 g. It is set to be equal to the moving distance of the inner cylinder 18.

Next, how to use this paper property measuring member 15 will be explained with reference to FIGS. 2 to 4. First, the switching motor 23 is operated to align the air exhaust hole 20a of the lower press-fitting body 20 with a predetermined location of the upper press-fitting body 19. Next, when the paper 14 is sandwiched between the upper pressing member 19 and the lower pressing member 20, the inner cylinder 18 pushes the internal air downward with a constant pressing force of 567±1.0 g. This air passes through the paper 14 from the upper pressing body 19 to the lower pressing body 20 as indicated by the arrow in FIG.

When 100cc of air is exhausted, the inner cylinder 18
The light emitting sensor 18a moves from a position facing the upper light receiving sensor 21 to a position facing the lower light receiving sensor 22. Measure the time required for this movement. The value expressed in seconds is the air permeability of the paper 14.

After measuring the air permeability of the paper 14, the switching motor 23 is operated to align the smoothness measuring portion 20b of the lower pressure contact member 20 with a predetermined location on the upper pressure contact member 19. Next, when the paper 14 is sandwiched between the upper pressing member 19 and the lower pressing member 20, the inner cylinder 18 pushes the internal air downward with a constant pressing force of 567±1.0 g. This air advances to the lower side of the upper pressure member 19 as indicated by the arrow in FIG. 4, and escapes to the outside through the gap between the upper pressure member 19 and the paper 14 along the upper surface of the paper 14.

When 100 cc of air escapes, the light emitting sensor 18a of the inner cylinder 18 moves from the position facing the upper light receiving sensor 21 to the position facing the lower light receiving sensor 22. Measure the time required for this movement. The value expressed in seconds is the surface smoothness of the paper 14.

This electrophotographic copying machine C determines whether the air permeability and surface smoothness of the paper 14 measured by the paper physical property measuring member 15 are larger or smaller than predetermined values, respectively.
The fixing temperature, that is, the heating temperature of the heat roller 12 can be controlled. That is, this electrophotographic copying machine C
is equipped with a fixing control means for setting the heating temperature of the heat roller 12 to an optimum value based on the measurement results obtained by the paper property measuring member 15.

That is, the measured air permeability of the paper 14 is 2.
If the air permeability is less than 3 seconds, the heating temperature of the heat roller 12 is controlled to 185°C, and if the air permeability is 23 seconds or more, the heating temperature of the heat roller 12 is controlled to 200°C. Also, paper 1
If the surface smoothness of No. 4 is less than 27 seconds, the heating temperature of the heat roller 12 is controlled to 200°C, and if the surface smoothness is 27 seconds or more, the heating temperature of the heat roller 12 is controlled to 185°C. These temperature controls are performed by inputting numerical values into the ROM in advance.

Here, the heating temperature of the heat roller 12 is set to 185
℃ or 200℃, if the temperature of the heat roller 12 is 200℃, regardless of the air permeability of the paper 14, and if the temperature of the heat roller 12 is 185℃, the air permeability of the paper 14 is 23 seconds. This is because in the following cases, the toner fixation rate A becomes the desired 90% or more. Also, if the temperature of the heat roller 12 is 200°C, the surface smoothness of the paper 14 is 20 seconds or more, and if the temperature of the heat roller 12 is 185°C, the surface smoothness of the paper 14 is 27 seconds or more. Second, in both cases, the toner fixation rate B becomes the desired 95% or higher.

[0023] Here, the toner fixation rate A is determined by a specific peeling test, and represents the degree of adhesion between the paper 14 and the toner layer on its surface, and determines whether or not the fixation of the image area is uniform. This is a guideline. The toner fixation rate B is determined by a specific friction test, and represents the degree of binding force between the molten toners on the surface of the paper 14, and is used to determine whether the image area is well fixed. It is a measure of how much the object to be rubbed gets dirty due to friction.

It has been empirically found that when the toner fixation rate A is 90% or more, toner does not peel off when the paper 14 on which an image is formed is folded. In addition, if the toner fixation rate B is 95% or more, when writing on the paper 14 on which an image is formed, arm stains (a phenomenon in which the part of the arm or clothing that touches the paper from the elbow to the wrist is stained with toner) ) has been found empirically to not occur.

In this electrophotographic copying machine C, the heating temperature of the heat roller 12 is set to 9 depending on whether the air permeability and surface smoothness of the copy paper 14 are larger or smaller than predetermined values.
Temperature that can ensure toner fixation rate A of 0% or more and toner fixation rate B of 95% or more, that is, 200 ° C. or 185 ° C.
Can be set to either °C. Therefore, toner fixability is good on any of the various types of copy paper 14, and a clear fixed image without offset can be obtained. In particular, it is possible to prevent the risk of toner peeling off when the copied paper 14 is folded, and it is also possible to prevent the risk of staining the arm when writing on the paper 14.

The paper property measuring member 15 is also provided with a light emitting sensor 18a, and an upper light receiving sensor 21 and a lower light receiving sensor 22 facing the light emitting sensor 18a. As described above, the distance between the upper light receiving sensor 21 and the lower light receiving sensor 22 is constant (567±
When pushed downward with a pressing force of 1.0 g), the inner cylinder 18
is set equal to the moving distance of the inner cylinder 18 required to push out a certain amount (100 cc) of air inside the inner cylinder 18. Therefore, this paper property measuring member 15 eliminates the trouble of having to operate while checking the discharge of a certain amount of air with a scale or barometer, and easily measures the air permeability and surface smoothness of the paper 14. It becomes possible to measure.

[0027]

Effects of the Invention Since the paper physical property measuring device of the present invention is constructed as described above, it eliminates the trouble of having to operate while checking the discharge of a certain amount of air with a scale or barometer, and It becomes possible to easily measure physical properties such as air permeability and surface smoothness.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of an image forming apparatus incorporating a paper physical property measuring member, which is an embodiment of the present invention.

FIG. 2 is an enlarged configuration explanatory diagram illustrating the paper physical property measuring member and its control method in FIG. 1;

FIG. 3 is an explanatory diagram of the configuration when measuring the air permeability of paper using the paper physical property measuring member in FIG. 2;

FIG. 4 is an explanatory diagram of the configuration when measuring the surface smoothness of paper using the paper physical property measuring member in FIG. 2;

[Explanation of symbols]

1 Paper feed cassette 2 Primary paper feed roller 3 Secondary paper feed roller 4 Developing unit 5 Photosensitive drum 6 Optical unit 7 Main charger 8 Transfer/separation unit 9
Cleaning unit 10 Paper ejection roller 11 Document platen cover 12 Heat roller 13 Pressure roller 14 Copy paper (image forming paper) 15
Paper property measuring member (paper property measuring device)
16 Light spindle oil 17 Outer cylinder (cylinder) 18
Inner cylinder (piston) 18a Luminescence sensor 19 Upper pressure contact body 20 Lower pressure contact body 20a Air discharge hole 20b Smoothness measuring section 21 Upper light receiving sensor 22 Lower light receiving sensor

Claims (1)

[Claims] Claim 1: An outer cylinder extending vertically, an inner cylinder for discharging air that can freely slide up and down within the outer cylinder, and an air exhaust cylinder provided under the outer cylinder to discharge air in the inner cylinder downward. The upper pressure contact body is provided with an upper pressure contact body for passing through, and a lower pressure contact body provided below the upper pressure contact body and capable of sandwiching a physical property measurement paper between the upper pressure contact body, and an upper part of the outer surface of the peripheral wall of the inner cylinder. a luminescent sensor that emits light approximately horizontally outward; a protruding wall provided on the outer cylinder in an upwardly protruding manner; A paper property measuring device comprising an upper light-receiving sensor and a lower light-receiving sensor that receive light.