阅读说明：本技术 测定装置、图像形成装置以及测定方法 (Measuring device, image forming apparatus, and measuring method ) 是由 东由美子 小片智史 吉村和俊 浅野齐 关裕正 石川明正 于 2020-02-06 设计创作，主要内容包括：本发明抑制在通过多个辊对来搬送片材的搬送路径上检测片材的物性值时的对片材的损伤以及搬送卡纸的产生。在具备在利用多个辊对搬送片材的搬送路径上检测片材的物性值的物性值检测部、以及构成为能够在与片材的面正交的方向上移动,并将片材推压到物性值检测部的推压部件的测定装置中,执行：停止片材的搬送,并使用推压部件将片材推压到物性值检测部,来检测片材的物性值的第一处理；在片材的物性值检测后,解除推压部件的推压使片材与物性值检测部分离,并开始片材的搬送的第二处理；以及基于反复实施第一处理和第二处理而检测出的片材的面内的多处的物性值,来确定片材的物性值的物性值确定处理。(The invention provides a sheet conveyance device which can prevent damage to a sheet and occurrence of conveyance jam when detecting a physical property value of the sheet on a conveyance path for conveying the sheet by a plurality of roller pairs. In a measuring apparatus including a physical property value detecting section for detecting a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs, and a pressing member configured to be movable in a direction orthogonal to a surface of the sheet and to press the sheet against the physical property value detecting section, the measuring apparatus executes: a first process of stopping conveyance of the sheet and pressing the sheet against the physical property value detection unit using the pressing member to detect the physical property value of the sheet; a second process of releasing the pressing of the pressing member to separate the sheet from the physical property value detecting portion and starting the conveyance of the sheet after the physical property value of the sheet is detected; and a physical property value specifying process for specifying a physical property value of the sheet based on physical property values at a plurality of points in the surface of the sheet detected by repeating the first process and the second process.)

1. A measurement device is provided with: a physical property value detection unit that detects a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs; and a pressing member configured to be movable in a direction orthogonal to a surface of the sheet and to press the sheet against the physical property value detection unit,

the measurement device is characterized by comprising:

a first control unit configured to control a first process of detecting a physical property value of the sheet by stopping conveyance of the sheet and pressing the sheet against the physical property value detecting unit by the pressing member;

a second control unit configured to control a second process of separating the sheet from the physical property value detection unit by releasing the pressing of the pressing member after detecting the physical property value of the sheet, and starting the conveyance of the sheet; and

and a physical property value specifying unit that specifies a physical property value of the sheet based on physical property values at a plurality of locations in the surface of the sheet detected by repeating the first process and the second process.

2. The assay device according to claim 1,

comprises an opposed plate opposed to the pressing member with the sheet interposed therebetween,

the first control unit detects the physical property value of the sheet by sandwiching the sheet between the pressing member and the opposed plate and pressing the opposed plate against the physical property value detecting unit.

3. The assay device according to claim 1 or 2,

the plurality of roller pairs include a first roller pair on an upstream side of the conveyance path and a second roller pair on a downstream side of the physical property value detection unit,

the first control unit detects a physical property value of the sheet in a state where the sheet is held by one of the first roller pair or the second roller pair.

4. The assay device according to claim 3,

one of the first roller pair or the second roller pair is configured to be capable of adjusting an interval between the rollers,

the first control unit detects a physical property value of the sheet while increasing a gap between the rollers of the one roller pair and holding the sheet by the other roller pair.

5. The measurement device according to any one of claims 1 to 4,

a sheet front end detecting section for detecting a front end of the sheet on the conveying path,

when the sheet front end detection unit detects the front end of the sheet, the first control unit performs a first physical property value detection.

6. An image forming apparatus for forming an image on the sheet,

the image forming apparatus is characterized in that,

the measuring apparatus according to any one of claims 1 to 5,

the image forming conditions for the sheet are set based on the physical property values of the sheet determined by the measuring device.

7. The image forming apparatus according to claim 6,

the measuring device is disposed in the conveyance path between a paper feeding section and an alignment section of the image forming apparatus.

8. A measurement method in a measurement device, the measurement device comprising: a physical property value detection unit that detects a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs; and a pressing member configured to be movable in a direction orthogonal to a surface of the sheet and to press the sheet against the physical property value detection unit,

the measurement method is characterized in that the measurement method executes:

a first process of stopping conveyance of the sheet and detecting a physical property value of the sheet by pressing the sheet against the physical property value detecting section using the pressing member;

a second process of releasing the pressing of the pressing member to separate the sheet from the physical property value detection unit and starting the conveyance of the sheet after the physical property value of the sheet is detected; and

and a physical property value specifying process of specifying a physical property value of the sheet based on physical property values at a plurality of points in the surface of the sheet detected by repeating the first process and the second process.

9. The method of measuring according to claim 8,

the measuring device is provided with an opposed plate opposed to the pressing member with the sheet interposed therebetween,

in the first process, the sheet is sandwiched between the pressing member and the opposing plate, and the opposing plate is pressed against the physical property value detection unit, thereby detecting the physical property value of the sheet.

10. The method of measuring according to claim 8 or 9,

the plurality of roller pairs include a first roller pair on an upstream side of the conveyance path and a second roller pair on a downstream side of the physical property value detection unit,

in the first process, a physical property value of the sheet is detected in a state where the sheet is held by one of the first roller pair or the second roller pair.

11. The method of measuring according to claim 10,

one of the first roller pair or the second roller pair is configured to be capable of adjusting an interval between the rollers,

in the first process, the physical property value of the sheet is detected while the distance between the rollers of the one roller pair is increased and the sheet is held by the other roller pair.

12. The method of measuring according to any one of claims 8 to 11,

the image forming apparatus includes a sheet front end detecting section that detects a front end of the sheet on the conveyance path,

in the first process, when the sheet leading end detection unit detects the leading end of the sheet, the first physical property value detection is performed.

Technical Field

The present invention relates to a measuring apparatus, an image forming apparatus, and a measuring method, and more particularly to a measuring apparatus for detecting a physical property value of a sheet, an image forming apparatus including the measuring apparatus, and a measuring method for detecting a physical property value of a sheet.

Background

There is known a measuring apparatus including a function of detecting a physical property value of a sheet by providing a detecting portion for detecting the physical property value of the sheet on a conveyance path for conveying a recording medium such as the sheet by a plurality of roller pairs (opposing rollers) to determine a type, a basis weight, and the like of the sheet conveyed by the roller pairs. By providing the above-described measuring device in an image forming apparatus such as an MFP (Multi-functional peripherals), and setting the image forming conditions based on the type, basis weight, and the like of the discriminated sheet, it is possible to form an image corresponding to the sheet.

In the conveyance of a sheet by a roller pair, the sheet is conveyed by being transferred from an upstream roller pair arranged on a conveyance path to a downstream roller pair. In order to improve the accuracy of detecting the physical property value of the sheet, it is necessary to make the positional relationship between the detecting portion and the sheet constant and perform detection under the same condition every time.

As for a device including such a detection unit, for example, patent document 1 below discloses a device including: a paper front end detection mechanism for detecting the paper front end of the manuscript taken out from the paper feeding tray and conveyed on the manuscript conveying path; and a paper thickness detection mechanism for detecting the paper thickness of the original conveyed on the original conveying path through the paper front end detection mechanism, wherein in the original overlapped conveying detection device for judging the overlapped conveying of the original during the original conveying based on the information of the paper front end of the original detected by the paper front end detection mechanism and the paper thickness of the original detected by the paper thickness detection mechanism, a structure of an original pressing member for pressing the original conveyed on the original conveying path is arranged before the original measuring position performed by the paper thickness detection mechanism.

Patent document 2 discloses a technique of including: a sheet discriminating device having an information detecting means for detecting information on a sheet by causing a light emitting means to emit light and receiving the light applied to the sheet by a light receiving means, and a discriminating means for discriminating the sheet based on the information on the sheet detected by the information detecting means, the sheet discriminating device comprising: a displacement member that starts displacement from an initial position at which the sheet is not sandwiched between the displacement member and an opposing member by sandwiching the sheet moving in the apparatus between the displacement member and the opposing member; and a displacement amount detection means for detecting a displacement amount of the displacement member, wherein the information detection means is configured as a sheet thickness detection means for detecting a thickness of the sheet based on a detection result of the displacement amount detection means.

Patent document 1: japanese laid-open patent publication No. 7-172631

Patent document 2: japanese patent laid-open publication No. 2015-205775

When a sheet is conveyed while being pressed against a detection portion on a conveyance path where the sheet is conveyed by a roller pair, particularly, since the sheet is weak in rigidity, the posture of the sheet conveyed from the roller pair cannot be maintained (the leading end portion of the sheet hangs down due to its own weight), and therefore, if an obstacle exists on the conveyance path, there is a problem that the sheet is caught by the obstacle and torn, or a conveyance jam such as a jam occurs, and productivity is lowered.

Disclosure of Invention

The present invention has been made in view of the above problems, and a main object of the present invention is to provide a measurement device, an image forming apparatus, and a measurement method that can suppress damage to a sheet and occurrence of conveyance jam when detecting a physical property value of the sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs.

One aspect of the present invention is a measuring apparatus including a physical property value detecting unit that detects a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs, and a pressing member that is configured to be movable in a direction orthogonal to a surface of the sheet and presses the sheet against the physical property value detecting unit, the measuring apparatus including: a first control unit configured to control a first process in which the conveyance of the sheet is stopped and the sheet is pressed against the physical property value detection unit by the pressing member to detect the physical property value of the sheet; a second control unit configured to control a second process in which, after the physical property value of the sheet is detected, the pressing member is released from pressing to separate the sheet from the physical property value detection unit, and the conveyance of the sheet is started; and a physical property value specifying unit that specifies a physical property value of the sheet based on physical property values at a plurality of locations in the surface of the sheet detected by repeating the first process and the second process.

One aspect of the present invention is a measurement method in a measurement device including a physical property value detection unit that detects a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs, and a pressing member that is configured to be movable in a direction orthogonal to a surface of the sheet and presses the sheet against the physical property value detection unit, the measurement method including: a first process of stopping conveyance of the sheet and pressing the sheet against the physical property value detection unit using the pressing member to detect the physical property value of the sheet; a second process of releasing the pressing of the pressing member to separate the sheet from the physical property value detecting section and starting the conveyance of the sheet after the physical property value of the sheet is detected; and a physical property value specifying process for specifying a physical property value of the sheet based on physical property values at a plurality of points in the surface of the sheet detected by repeating the first process and the second process.

According to the measurement device, the image forming apparatus, and the measurement method of the present invention, when the physical property value of the sheet is detected on the conveyance path through which the sheet is conveyed by the plurality of roller pairs, damage to the sheet and occurrence of a jam can be suppressed.

The reason is that: in a measuring apparatus including a physical property value detecting section for detecting a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs, and a pressing member configured to be movable in a direction orthogonal to a surface of the sheet and to press the sheet against the physical property value detecting section, the measuring apparatus executes: a first process of stopping conveyance of the sheet and pressing the sheet against the physical property value detection unit using the pressing member to detect the physical property value of the sheet; a second process of releasing the pressing of the pressing member to separate the sheet from the physical property value detecting portion and starting the conveyance of the sheet after the physical property value of the sheet is detected; and a physical property value specifying process for specifying a physical property value of the sheet based on physical property values at a plurality of points in the surface of the sheet detected by repeating the first process and the second process.

Drawings

Fig. 1 is a schematic diagram showing a configuration of an image forming apparatus including a measuring apparatus according to an embodiment of the present invention.

Fig. 2 is a block diagram showing a configuration of an image forming apparatus including a measuring apparatus according to an embodiment of the present invention.

Fig. 3 is a schematic diagram showing the structure of a measuring apparatus according to an embodiment of the present invention.

FIG. 4 is a schematic view showing another configuration of a measuring apparatus according to an embodiment of the present invention.

Fig. 5 is a schematic diagram showing the operation of the measuring apparatus according to the embodiment of the present invention, and shows a case where both ends of a sheet are bound.

Fig. 6 is a schematic diagram showing the operation of the measuring apparatus according to the embodiment of the present invention, and shows a case where both ends of the sheet are not bound.

Fig. 7 is a schematic diagram showing the operation of the measuring apparatus according to the embodiment of the present invention, and shows a structure in which one end of the sheet is released.

Fig. 8 is a flowchart showing the operation of the measuring apparatus according to the embodiment of the present invention.

Fig. 9 is a perspective view and a side sectional view showing an example of the structure of a conventional measuring apparatus.

Fig. 10 is a schematic diagram illustrating a problem in the conventional measurement device.

Detailed Description

As described in the background art, there is known a measuring apparatus having a function of detecting a physical property value of a sheet by a detecting section provided on a conveyance path for conveying the sheet by a plurality of roller pairs, and discriminating a type, a basis weight, and the like of the sheet. By providing the image forming apparatus with the measurement device, the image forming conditions are set based on the type, basis weight, and the like of the sheet thus determined, and an image corresponding to the sheet can be formed. Here, in order to improve the accuracy of detecting the physical property value of the sheet, it is necessary to make the positional relationship between the detecting portion and the sheet constant, and to perform detection under the same condition every time.

As a method for solving this problem, for example, as in patent document 1, a method is conceivable in which a regulating member is provided on a conveyance path to regulate the leading end of a sheet and detect the leading end, but in this method, the sheet swings in a range from the regulating member to a detection position, and the distance between a detection portion and the sheet changes, thereby lowering the detection accuracy.

On the other hand, in the case of a measuring device in which a sheet is manually inserted as in patent document 2, as shown in fig. 9, an operator can grasp the leading end portion (hatched portion with oblique lines in the drawing) of the sheet 110 and insert it into the measuring device 120. Therefore, the distance between the detection portion 121 and the sheet 110 can be kept constant, and a decrease in detection accuracy can be suppressed. In this method, even when the sheet 110 is pressed against the detection portion 121 and inserted, the sheet 110 is less likely to be damaged.

However, as shown in fig. 10, when the sheet 110 is conveyed by the plurality of roller pairs 123, the sheet 110 is particularly weak in rigidity, and the posture of the sheet 110 conveyed from the roller pairs 123 cannot be maintained (the leading end portion of the sheet 110 hangs down due to its own weight). Therefore, if there is an obstacle such as the pressing mechanism 122 that presses the sheet 110 against the detection portion 121 on the conveyance path, the leading end of the sheet 110, which is weak in rigidity, may be torn by the obstacle, or a conveyance jam such as a jam may occur, which may result in a problem of reduced productivity.

Therefore, in one embodiment of the present invention, a measurement device including a physical property value detection unit configured to detect a physical property value of a sheet on a conveyance path through which the sheet is conveyed by a plurality of roller pairs, and a pressing member configured to be movable in a direction orthogonal to a surface of the sheet and to press the sheet against the physical property value detection unit, executes: a first process of stopping conveyance of the sheet and pressing the sheet against the physical property value detection unit using the pressing member to detect the physical property value of the sheet; a second process of releasing the pressing of the pressing member to separate the sheet from the physical property value detecting portion and starting the conveyance of the sheet after the physical property value of the sheet is detected; and a physical property value specifying process for specifying a physical property value of the sheet based on physical property values at a plurality of points in the surface of the sheet detected by repeating the first process and the second process.

Specifically, in a measurement device including a pressing member that presses a sheet against a detection portion, when the conveyed sheet reaches the detection portion, conveyance of the sheet is temporarily stopped, and the sheet is pressed against the detection portion using the pressing member (when an opposing plate opposing the pressing member is provided, the sheet is sandwiched between the pressing member and the opposing plate, and the opposing plate is pressed against the detection portion), thereby detecting a physical property value. After the physical property value is detected, the pressing of the pressing member is released, the sheet is separated from the detection unit (or the opposed plate), the conveyance of the sheet is stopped again after a predetermined distance is carried out, the physical property value is detected, and the physical property value of the sheet is determined based on a plurality of physical property values by performing the process a plurality of times.

Here, when the sheet is pressed against the detection portion by the pressing member, if the sheet is held by the roller pairs on both the upstream side and the downstream side of the detection portion and both ends of the sheet are bound, damage such as sheet breakage or indentation may be generated in the pressing. Therefore, the sheet is pressed against the detection portion in a state where any one of the upstream and downstream sides of the sheet is not held by the roller pair in the detection portion.

Therefore, for example, when one of the upstream and downstream roller pairs is separable (the distance between the rollers can be adjusted), when the physical property value is detected, one of the upstream and downstream roller pairs is separated, and thus any one of the upstream and downstream of the sheet is not held by the roller pair in the detection portion (only one side is held). Alternatively, when the sheet leading end detecting portion for detecting the leading end of the sheet is disposed, the physical property value can be detected in a state where the leading end of the sheet does not reach the roller pair or the trailing end is separated from the roller pair by adjusting the disposition of the sheet leading end detecting portion, the detection interval of the physical property value, and the like.

By performing such control, it is possible to suppress damage to the sheet and occurrence of conveyance jam at the time of detection of the physical property value.