JP3105754B2 - Paper thickness detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet thickness detecting apparatus capable of easily detecting an abnormality when a sheet is double-fed.

[0002]

2. Description of the Related Art Conventionally, a technique disclosed in Japanese Patent Application Laid-Open No. 2-152842 is known as a technique for detecting the thickness of a sheet. The sheet thickness detecting device disclosed in this publication is provided on a movable lever that is swingable about a fixed shaft, and conveys the sheet while sandwiching the sheet with a rotating roller driven by a drive motor. An idler roller, a resistive film provided on the movable lever, which senses light emitted from the light emitting device and outputs a light amount of the light as a resistance value, and a resistance value detected by the resistance film. And a CPU that calculates the amount of swing of the idler roller about the fixed axis, based on the amount of swing of the idler roller about the fixed axis. The thickness of the sheet sandwiched between the rolling roller and the rotating roller is detected, thereby detecting an abnormality such as double feeding of the sheet and affixing a tape to the sheet. It has become so.

[0003]

By the way, in the sheet thickness detecting device described in the above publication, the double feeding of the sheet is performed based on the swing of the idle roller about the fixed shaft. ,
Abnormalities such as tape affixing on paper sheets are detected.For thin paper sheets, the swing amount about the fixed shaft of the idler roller is extremely small. Even if the sheet is transported by the double feed, it is not possible to reliably detect the abnormality of the double feed, and there has been a problem that the accuracy of the abnormality detection is poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and the accuracy of abnormality detection that can reliably detect abnormalities such as when double-fed thin paper sheets are fed is improved. An object of the present invention is to provide a high sheet thickness detecting device.

[0005]

In order to achieve the above object, according to a first aspect of the present invention, a paper sheet is provided so as to be displaceable in a direction approaching and away from a fixed roller, and a paper sheet is interposed between the fixed roller and the fixed roller. A movable roller to be sandwiched, a beam light irradiating unit for irradiating the beam light, a beam light bending unit having a lens that bends the optical axis of the beam light emitted from the beam light irradiating unit according to the displacement amount of the movable roller, The light receiving means is fixed to the apparatus main body, receives the light beam passing through the lens of the light beam bending means, and outputs a detection signal indicating a light receiving position of the light beam, and is indicated by the detection signal from the light receiving means. Thickness detecting means for detecting a displacement amount of the movable roller based on a light receiving position of the light beam and detecting a thickness of a sheet sandwiched between the fixed roller and the movable roller. Characterized by .

In the second invention, the beam bending means shown in the first invention is fixed to the main body of the apparatus, and is operatively associated with the beam irradiating means for irradiating the lens with the beam light and the movable roller. A lens fixed to the interlocking rod, transmitting the light beam emitted from the light beam irradiation means, and bending the optical axis of the light beam in accordance with the transmission position of the light beam. I do.

In a third aspect, the beam light bending means shown in the first aspect is fixed to an interlocking rod interlocking with a movable roller to irradiate the lens with a light beam, and an apparatus main body. A lens that is fixed to the portion, transmits the light beam emitted from the light beam irradiation means, and bends the optical axis of the light beam according to the transmission position of the light beam. .

A fourth aspect of the present invention is characterized in that a concave lens is used as a lens of the light beam bending means according to the first to third aspects.

According to a fifth aspect of the present invention, the beam bending means shown in the first to fourth aspects is fixed to the main body of the apparatus, and the beam bending means for irradiating the reflecting mirror means with the light beam; A reflecting mirror means fixed to an interlocking rod interlocking with the roller and reflecting the light beam emitted from the light beam irradiation means; and a beam light fixed to the interlocking rod together with the reflecting mirror means and reflected by the reflecting mirror means And a lens that bends the optical axis of the light beam in accordance with the transmission position.

A sixth invention is characterized in that a prism is used as the reflecting mirror means according to the fifth invention.

[0011]

In the sheet thickness detecting device according to the first aspect,
A beam bending unit having a lens that bends the optical axis of the beam irradiated from the beam irradiating unit in accordance with the displacement of the movable roller is provided, and the beam passing through the beam bending unit is received by the light receiving unit. Thereafter, the thickness detecting means detects the displacement amount of the movable roller based on the light receiving position of the light beam indicated by the detection signal from the light receiving means, and the paper held between the fixed roller and the movable roller. Detect leaf thickness. That is, in the present invention, the light beam bent in accordance with the displacement amount of the movable roller is received by the light receiving means located at a position distant from the movable roller without directly detecting the displacement amount of the movable roller as in the related art. However, since the detection is performed by doubling the displacement amount of the movable roller, a minute displacement of the movable roller can also be detected. In this case, the abnormality can be reliably detected.

In the sheet thickness detecting apparatus according to the second aspect of the invention, the lens is irradiated with beam light from the beam light irradiating means fixed to the apparatus main body, and then fixed to the interlocking rod. Since the lens transmits the light beam and bends the optical axis of the light beam in accordance with the transmission position of the light beam, the displacement of the lens in accordance with the displacement of the movable roller causes the beam in the lens to be bent. The light transmission position is changed, so that the beam light can be bent accurately in accordance with the displacement amount of the movable roller.

In the sheet thickness detecting device according to a third aspect of the present invention, the light beam is emitted from the light beam irradiating means fixed to an interlocking rod interlocking with a movable roller toward a lens fixed to the apparatus main body. After irradiating the light beam, the lens bends the optical axis of the light beam according to the transmission position of the light beam. The transmission position of the light beam in the lens is changed, so that the light beam can be bent accurately according to the amount of displacement of the movable roller, as in the second invention.

In the sheet thickness detecting apparatus according to the fourth aspect of the present invention, the beam light can be bent by using a concave lens as the beam light bending means, whereby the light receiving means bends the light beam. Direction. Further, since the light beam enters from the rear focal direction of the concave lens, the light beam is bent outward. In other words, the light beam transmitted through the concave lens is immediately amplified in the amount of displacement and irradiated, so that the light receiving means and the concave lens can be arranged at a short distance.

In the sheet thickness detecting apparatus according to a fifth aspect of the present invention, the light beam irradiating means fixed to the apparatus main body irradiates the reflecting mirror means with light beam and then fixed to the interlocking rod. The reflected mirror means reflects the beam light emitted from the beam light irradiating means, and further, a lens fixed to the interlocking rod together with the reflecting mirror means, according to the transmission position of the light beam, Since the optical axis is bent, the transmission position of the light beam in the lens is changed by the displacement of the reflecting mirror means in accordance with the displacement of the movable roller, whereby the movable roller is moved similarly to the second and third inventions. It is possible to accurately bend the light beam according to the displacement amount of the light beam.

In the paper sheet thickness detecting apparatus according to the sixth invention, a prism is used as the reflecting mirror means.
With this prism, the light beam can be bent in an arbitrarily set direction, and thus the light receiving means can be arranged at an arbitrary position.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1 to FIG. 3, a reference numeral 1 denotes a paper sheet transport path on which the paper sheet S is transported,
A fixed roller 2 and a movable roller 3 that sandwich the sheet S are disposed below and above the sheet transport path 1.
The fixed roller 2 includes a spindle 2 fixed to the apparatus main body 100.
It is supported rotatably about A. The movable roller 3 is rotatably supported around a support shaft 4 by a roller support member (not shown), and is supported so as to be displaceable in a direction approaching and separating from the fixed roller 2 (arrow ab direction). Further, the support shaft 4 is provided with an interlocking rod 5 which is displaced in the directions of arrows ab in conjunction with the movable roller 3.

On the other hand, at the upper end of the interlocking rod 5,
A concave lens 6 having a lens axis 51 having a positional relationship orthogonal to the displacement direction (the direction of the arrow ab) is fixed to the concave lens 6, and the light beam emitted from the light source 7 fixed to the apparatus main body 100 is fixed to the concave lens 6. 50 are illuminated. The apparatus main body 100 located on the opposite side of the light source 7 across the concave lens 6 detects the light receiving position of the light beam 50 passing through the concave lens 6 and outputs a detection signal indicating the light receiving position of the light beam 50. A light receiving element 8 is disposed. The light receiving element 8 is constituted by, for example, a CCD array or the like including a large number of detecting elements.

The positions of the light source 7, the concave lens 6, and the light receiving element 8 are set so as to have the following relationship. That is, the concave lens 6 and the light source 7
The light source 7 is positioned in the back focal direction of the paper and normal paper S (one regular paper free of foreign matter such as tape: expressed as normal paper) is fixed by a fixed roller. When passing between the movable roller 3 and the movable roller 3, the optical axis of the emitted light beam 50 coincides with the lens axis 51 of the concave lens 6,
Further, when the normal paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3, the light receiving element 8 is arranged such that the optical axis of the light beam 50 that has passed through the concave lens 6 is at the center (hereinafter, this position is referred to as , The light receiving position m1) (see FIG. 2).

Then, such a light source 7, a concave lens 6,
When nothing is sandwiched between the fixed roller 2 and the movable roller 3 due to the arrangement of the light receiving element 8, the optical axis of the emitted light beam 50 is located above the lens axis 51 of the concave lens 6, Thus, the vicinity of the upper end of the light receiving element 8 becomes a light receiving position of the light beam 50 (indicated by reference numeral m0 in FIG. 1). When a sheet S thicker than a normal sheet is sandwiched between the fixed roller 2 and the movable roller 3, as shown in FIG. Is positioned below the lens axis 51 of the light receiving element 8 so that the vicinity of the lower end of the light receiving element 8 is located at the light receiving position of the light beam 50 (FIG.
Is indicated by a symbol m2).

Next, a control circuit of the sheet thickness detecting device will be described with reference to FIG. This control circuit has a CP
U10, ROM 11 connected to CPU 10, RA
M12, a light source 7, a light receiving element 8, and a discrimination circuit 13.
0 and the program of the discriminating circuit 13 together with the light receiving element 8
Of displacement of light receiving position of light beam 50 detected by
Reference displacement amount M0 (described later) to be compared with (described later)
Is stored in advance.

Based on a detection signal indicating the light receiving position of the light beam 50 output from the light receiving element 8, the discriminating circuit 13 changes from a state in which there is no object between the fixed roller 2 and the movable roller 3 (see FIG. 1). In the case where a sandwiched object is sandwiched between the fixed roller 2 and the movable roller 3 (see FIGS. 2 and 3),
Light receiving position m1 of light beam 50 detected by light receiving element 8
Calculating a displacement amount M indicating how much the m2 is displaced from the light receiving position m0, and calculating the displacement amount M when the normal paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3; It is determined whether or not the sandwiched object is a normal paper sheet S based on whether or not the displacement amount matches the displacement amount M0 (indicated by the difference between the light receiving position m0 and the light receiving position m1). That is, the discriminating circuit 13 calculates the displacement M of the light beam 50 based on the detection signal indicating the light receiving position of the light beam 50 output from the light receiving element 8, and stores the displacement M and the stored value in the ROM 11. Is compared with the reference displacement amount M0, and when the displacement amount M and the reference displacement amount M0 match, the paper sheet S sandwiched between the fixed roller 2 and the movable roller 3 is determined to be normal. If the displacement M and the reference displacement M0 do not match, the sheet S sandwiched between the fixed roller 2 and the movable roller 3 is determined to be abnormal. RAM
Numeral 12 stores the number of sheets S determined to be normal by the discriminating circuit 13. All the predetermined sheets S are
When the sheet passes through the fixed roller 2 and the movable roller 3, this number is output as a count value of the regular sheets S.

Next, the operation of the sheet thickness detecting apparatus will be described. First, as shown in FIGS. 2 to 3, when a sheet S is conveyed along the sheet conveying path 1 and the sheet S is sandwiched between the fixed roller 2 and the movable roller 3. The movable roller 3 is pushed up in the direction of arrow b, and accordingly, the concave lens 6 at the upper end of the movable roller 3 is pushed up in the direction of arrow b. Then, the sheet S is sandwiched between the fixed roller 2 and the movable roller 3 as described above, and the concave lens 6 is moved in the direction of the arrow b.
When pushed up in the direction, the determination circuit 13 detects how the light receiving position of the light beam 50 has been displaced based on the detection signal indicating the light receiving position of the light beam 50 detected by the light receiving element 8, Based on the displacement amount M, the sheet S
Is determined.

That is, the paper sheet S is a normal paper sheet, and the optical axis of the light beam 50 from the light source 7 is
(See FIG. 2)
The discriminating circuit 13 discriminates the sheet S from being normal because the displacement M indicated by the difference between the light receiving position m1 and the light receiving position m0 detected by the light receiving element 8 matches the reference displacement M0. . On the other hand, if the paper sheet S is not a normal paper sheet and the optical axis of the light beam 50 from the light source 7 does not coincide with the lens axis 51 of the concave lens 7 (see FIG. 3), Light receiving position m detected by light receiving element 8
Since the displacement amount M indicated by the difference between 2 and the light receiving position m0 does not match the reference displacement amount M0, the sheet S is determined to be abnormal (double feed, foreign matter attached, etc.). I do.

In the first embodiment, the displacement M of the light receiving position (the light receiving position m0 and the light receiving position m0) when the object to be clamped is sandwiched from the state where there is no sheet S between the fixed roller 2 and the movable roller 3. It is determined whether or not the sheet S is normal based on the difference between the light receiving position m1 / m2). However, the present invention is not limited to this, and the normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3. In this case, the light receiving position m1 of the light beam 50 is set to the reference position "m
1 ", and whether the sheet S is normal or not may be determined based on how much the sheet S is displaced from the reference position. That is, when the sheet S is held between the fixed roller 2 and the movable roller 3, and the light receiving position of the light beam 50 at the light receiving element 8 is m1 at this time, the light receiving position m1 and the reference position "m1" Displacement amount M indicating the difference from
Becomes "0", the discrimination circuit 13 determines that the paper sheet S is normal, and the paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3. When the light receiving position of the light beam 50 in the light receiving element 8 is not m1 (for example, the light receiving position is m2), the displacement M indicating the difference between the light receiving position m1 and the reference position "m1" is "0". Therefore, the discrimination circuit 13 may determine that the sheet S is abnormal (that is, the reference displacement M0 is set to "0" at this time).

As described above in detail, in the sheet thickness detecting apparatus shown in this embodiment, the movable roller 3
Is not directly detected, and the light beam 50 bent in accordance with the displacement amount of the movable roller 3 is received by the light receiving element 8 located at a position distant from the movable roller 3. Is detected by doubling the amount of displacement of the movable roller 3, it is also possible to detect a minute displacement of the movable roller 3. For example, an abnormality when the thin paper S is double-fed is detected. Can also be reliably detected. Further, in this embodiment, after the light source 7 fixed to the apparatus main body 100 irradiates the light beam 50 toward the concave lens 6 linked to the movable roller 3, the concave lens 6 fixed to the link rod 5 is irradiated.
Is configured to transmit the light beam 50 and to bend the optical axis of the light beam 50 in accordance with the transmission position of the light beam 50. Therefore, the arrow a of the concave lens 6 corresponding to the displacement of the movable roller 3 Due to the displacement in the −b direction, the transmission position of the light beam 50 in the concave lens 6 changes, whereby the light beam 50 can be bent accurately in accordance with the amount of displacement of the movable roller 3. Anomaly detection can be performed with high accuracy.

In the first embodiment, the light source 7 constitutes the "beam light irradiating means" described in the claims, and the concave lens 6 and the light source 7 constitute the "beam light bending means" in the claims. Is done. Also, the light receiving element 8
This constitutes a “light receiving means” described in the claims, and the determination circuit 13 constitutes a “thickness detecting means” described in the claims.

In the first embodiment, the concave lens 6 is used as a lens constituting the beam bending means.
5 (corresponding to FIG. 2), FIG.
As shown in FIG. 3 (corresponding to FIG. 3), a convex lens 17 may be used. And when the convex lens 17 is used,
Since the refraction direction of the light beam 50 is opposite to that of the concave lens 6, the paper sheet S is placed between the fixed roller 2 and the movable roller 3.
Light receiving position m0 of the light receiving element 8 when is not clamped
Is near the lower end of the light receiving element 8 (see a light beam 50 indicated by a dashed line in FIG. 5), while a sheet S thicker than a normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3. In this case, the light receiving position m2 of the light receiving element 8 is near the upper end of the light receiving element 8 as shown in FIG. 6 (the light receiving position m1 of a normal sheet S remains unchanged: see FIG. (See the light beam 50 shown by the solid line). When the convex lens 17 is used, the light receiving element 8 is arranged at a position separated from the focal length of the convex lens 17 by more than twice.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, the same reference numerals are given to portions having the same configuration as in the first embodiment, and duplicate description will be omitted. The second embodiment is different from the first embodiment in the light source 15 and the concave lens 16 which constitute the beam bending means. That is, the light source 15 of the present embodiment is provided at the upper end of the interlocking rod 5 and emits a beam from the light source 15 in a direction orthogonal to the displacement direction of the movable roller 3 (the direction of the arrow ab). Light 50 is emitted. The concave lens 16 is fixed to the device main body 100 so as to be located between the light receiving element 8 and the concave lens 16 and emits the light beam 50 emitted from the light source 15 to the light source 1.
5 is bent in accordance with the movement in the directions of the arrows ab.

The light source 15, the concave lens 16, and the light receiving element 8 have the following relationship. These light sources 15
The concave lens 16 has a light beam 15 emitted when the light source 15 is positioned in the back focal direction of the concave lens 16 and a normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3. Is the lens axis 5 of the concave lens 16
7, the light receiving element 8 detects the light beam that has passed through the concave lens 16 when the normal paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3 as shown in FIG. 5
The position is set such that the optical axis 0 illuminates the center (light receiving position m1).

The light source 15 and the concave lens 1
6. If nothing is sandwiched between the fixed roller 2 and the movable roller 3 due to the arrangement of the light receiving element 8, the optical axis of the emitted light beam 50 (indicated by a one-dot chain line in FIG. 7)
The light receiving element 8 is located below the lens axis 51 of the concave lens 16, so that the vicinity of the lower end of the light receiving element 8 is a light receiving position of the light beam 50 (indicated by reference symbol m 0). When a sheet S thicker than the normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3, the optical axis of the emitted light beam 50 is changed to a concave lens as shown in FIG. The light receiving element 8 is located above the sixteen lens axes 51, so that the vicinity of the upper end of the light receiving element 8 becomes the light receiving position of the light beam 50 (indicated by reference numeral m 2 in FIG. 1).

On the other hand, in the discrimination circuit 13, the sheet S is a normal sheet, and the optical axis of the light beam 50 from the light source 16 is
When the lens axis 51 of the concave lens 16 is coincident (FIG. 7)
), The displacement M indicated by the difference between the light receiving position m1 and the light receiving position m0 on the light receiving element 8 is determined to be equal to the reference displacement M0, and the sheet S is determined to be normal. On the other hand, if the sheet S is not a normal sheet S and the optical axis of the light beam 50 from the light source 15 does not coincide with the lens axis 51 of the concave lens 16 (see FIG. 8), The displacement S indicated by the difference between the light receiving position m2 and the light receiving position m0 is determined to be inconsistent with the reference displacement M0. And so on). Note that the data processing of the discriminating circuit 13 is as follows.
This is the same as the first embodiment.

As described in detail above, the sheet thickness detecting apparatus shown in the second embodiment does not directly detect the displacement of the movable roller 3 as in the related art, but instead responds to the displacement of the movable roller 3. The light beam 50 that is bent is received by the light receiving element 8 located at a position distant from the movable roller 3, and the amount of displacement of the movable roller 3 is detected by doubling the light beam. 3 can also be detected, and for example, it is also possible to reliably detect an abnormality when a thin sheet is double-fed. The light source 15 fixed to the interlocking rod 5 linked to the movable roller 3 irradiates a light beam 50 toward the concave lens 16 fixed to the apparatus main body 100, and then the concave lens 16
Is configured to bend the optical axis of the light beam 50 in accordance with the transmission position of the light beam 50, so that the displacement of the optical axis of the light beam 50 in accordance with the displacement of the movable roller 3 causes the light beam in the concave lens 16 to be bent. This allows the beam light to be bent accurately in accordance with the amount of displacement of the movable roller 3 as in the first embodiment, making it possible to perform double feed detection with high accuracy. Become.

In the second embodiment, the concave lens 6 is used as the lens constituting the beam bending means.
9 (corresponding to FIG. 7), FIG.
As shown in FIG. 8 (corresponding to FIG. 8), a convex lens 18 may be used. And when the convex lens 18 is used,
Since the refraction direction of the light beam 50 is opposite to that of the concave lens 6, the paper sheet S is placed between the fixed roller 2 and the movable roller 3.
Light receiving position m0 of the light receiving element 8 when is not clamped
Is near the upper end of the light receiving element 8, while the light receiving position m2 of the light receiving element 8 when the sheet S thicker than the normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3.
Is near the lower end of the light-receiving element 8 (the light-receiving position m1 in the case of a normal sheet S does not change). Also, the convex lens 18
Is used, the light receiving element 8 is disposed at a position more than twice the focal length of the convex lens 18.

Next, a third embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. In the following description, the first
The same reference numerals are given to portions having the same configuration as that of the embodiment, and redundant description will be omitted. The third embodiment is different from the first embodiment in that a triangular prism 20 for reflecting a light beam 50 is added as a light beam bending means, and a concave lens 21 is provided instead of the concave lens 6; 8 is arranged on the light source 7 side. The triangular prism 20 has a base end rotatable around a support shaft 22 provided in the apparatus main body 100 and a distal end fixed to a movable arm 23 connected to the interlocking rod 5. The light beam 50 emitted from the light source 7 is incident on the triangular prism 20. And the incident light is
The light beam is transmitted / reflected through the triangular prism 20 and emitted to the light receiving element 8 on the incident side of the light beam 50. The movable arm 23 is rotatable about the support shaft 22 in one direction, and the other upper part is interlocked with the triangular prism 20 and the lower part is interlocked with the interlocking rod 5. With such a configuration, the bill S
The movable roller 3 is displaced in accordance with the thickness of the movable arm 3, and the movable arm 23 linked thereto is displaced about the support shaft 22.
Thus, the triangular prism 20 and the concave lens 21 provided at the tip of the movable arm 23 are displaced. Thereby, the incident position of the light beam 50 on the triangular prism 20 changes. In addition, the concave lens 21 bends the light beam 50 in response to a change in the emission position of the light beam 50 transmitted / reflected by the triangular prism 20, and
It is possible to change the direction of the emission position 1 of the light beam 50 irradiated on the light receiving element 8 disposed on the same side as that of the light receiving element 8, and thus change the light receiving position of the light receiving element 8.

That is, such a triangular prism 20,
Depending on the arrangement of the concave lens 21, these triangular prisms 2
0, the concave lens 21 can be rotationally displaced about the support shaft 22 in accordance with the displacement amount of the movable roller 3, that is, in accordance with the thickness of the paper sheet S. It is possible to change the incident angle and the incident position of 50, and the exit angle and the exit position from the triangular prism 20, respectively. As a result, it is possible to change the light receiving position of the light beam 50 irradiated to the light receiving element 8 through the concave lens 21. It becomes possible.

The light source 7, the triangular prism 20,
The concave lens 21 and the light receiving element 8 have the following relationship.
That is, the light source 7, the triangular prism 20, the concave lens 21
Is arranged such that the optical axis of the emitted light beam 50 coincides with the lens axis 51 of the concave lens 21 when the normal paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3 ( The light beam 50 shown by a solid line in FIG. 11)
When the normal paper sheet S is sandwiched between the fixed roller 2 and the movable roller 3 as shown in FIG. It is arranged to irradiate the lower end (light receiving position m1) of the element 8.

By the arrangement of the light source 7, the triangular prism 20, the concave lens 21, and the light receiving element 8, a sheet S thicker than the normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3. In this case, as shown in FIG.
The optical axis of the emitted light beam 50 is located above the lens axis 51 of the concave lens 21, whereby the light receiving position of the light beam 50 near the upper end of the light receiving element 8 (m 2 in FIG. 1)
).

On the other hand, in the ROM 11, the light receiving position m1 of the light beam 50 when the normal sheet S is sandwiched between the fixed roller 2 and the movable roller 3 is stored in the reference light receiving position "m1".
In the discriminating circuit 13, the displacement M indicating the displacement of the light receiving position from the reference light receiving position "m1" and the reference displacement M0 set in the ROM 11 are stored.
(= Set to “0”), it is determined whether or not the sheet S is normal. Specifically, a sheet S is sandwiched between the fixed roller 2 and the movable roller 3,
At this time, if the light receiving position of the light beam 50 in the light receiving element 8 is m1, the light receiving position m1 and the reference light receiving position "m
Since the displacement amount M indicating the difference from "1" becomes "0" and coincides with the reference displacement amount M0, the discrimination circuit 13 determines that the sheet S is normal (see FIG. 11). Further, a sheet S is sandwiched between the fixed roller 2 and the movable roller 3, and at this time, the light receiving position of the light beam 50 on the light receiving element 8 is m
If it is not 1, the displacement amount M indicating the difference between the light receiving position m1 and the reference light receiving position "m1" does not become "0". Therefore, the discrimination circuit 13 determines that the sheet S is abnormal. It is determined (see FIG. 12).

As described in detail above, in the sheet thickness detecting apparatus shown in the third embodiment, similarly to the first and second embodiments, the beam bent in accordance with the displacement of the movable roller 3 is used. The light 50 is received by the light receiving element 8 located at a position distant from the movable roller 3, thereby detecting the amount of displacement of the movable roller 3 by doubling it. Can also be detected, and for example, it is also possible to reliably detect an abnormality in the case where a thin sheet is double-fed. Also, after irradiating the light beam 50 from the light source 7 fixed to the apparatus main body 100 to the triangular prism 20 fixed to the interlocking rod 5 linked to the movable roller 3, the triangular prism 20 is irradiated from the light source 7. The concave lens 21 fixed to the interlocking rod 5 together with the triangular prism 20 reflects the light beam 50
Is bent in accordance with the transmission position of the light beam 50, the transmission position of the light beam 50 in the concave lens 21 is changed by the displacement of the triangular prism 20 in accordance with the displacement of the movable roller 3, and Thus, similarly to the first and second embodiments, the light beam 50 can be bent accurately according to the displacement amount of the movable roller 3, and the double feed detection can be performed with high accuracy. The use of such a triangular prism 20 makes it possible to set the light beam 50 to be reflected in an arbitrary direction, thereby allowing the arrangement of the concave lens 51 and the light receiving element 8 to have a degree of freedom. 51, light receiving element 8
It is possible to easily cope with the case where there is a restriction in the installation space.

Incidentally, the triangular prism 20 of the third embodiment is used.
This constitutes the "reflecting mirror means" described in the claims. Further, in the third embodiment, the triangular prism 20 is used as the reflecting mirror means.
The light beam 50 may be guided to the concave lens 21 by fixing one or a plurality of reflecting mirrors to the tip of the movable arm 23.

In the third embodiment, the triangular prism 20 and the movable roller 3 change in accordance with a change in the distance between the fixed roller 2 and the movable roller 3.
The concave lens 21 is displaced together to bend the optical axis of the light beam 50 emitted from the light source 7. At this time, the concave lens 21 is located on the incident light side of the triangular prism 20 or on the exit light side. If any one or two of the triangular prism 20, the light source 7, and the concave lens 6 are changed in accordance with the change in the distance between the fixed roller 2 and the movable roller 3, the light beam emitted from the light source 7 can be obtained. It is possible to bend the optical axis of the triangular prism 20 and move the optical axis of the triangular prism 2 and the concave lens 6.
The number may be only 0, or may be the triangular prism 20 and the light source 7, and the selection is arbitrary.

[0043]

As is clear from the above description, in the sheet thickness detecting apparatus according to the first invention, the optical axis of the light beam emitted from the light beam irradiating means is changed according to the displacement of the movable roller. A beam light bending means having a lens to be bent, the light beam passing through the beam light bending means being received by the light receiving means, and the beam light indicated by the detection signal from the light receiving means being received by the thickness detecting means. The amount of displacement of the movable roller is detected based on the light receiving position, and the thickness of the sheet sandwiched between the fixed roller and the movable roller is detected. That is, in the present invention, the light beam bent in accordance with the displacement amount of the movable roller is received by the light receiving means located at a position distant from the movable roller without directly detecting the displacement amount of the movable roller as in the related art. However, since the detection is performed by doubling the displacement amount of the movable roller, a minute displacement of the movable roller can also be detected.
It is also possible to reliably detect an abnormality when a thin sheet is double-fed.

In the sheet thickness detecting apparatus according to the second aspect of the present invention, the beam light irradiating means fixed to the apparatus main body irradiates the lens fixed to the interlocking rod with the beam light, and then the lens. Transmits the light beam and bends the optical axis of the light beam according to the transmission position of the light beam, so that the displacement of the lens according to the movement of the movable roller causes the transmission of the light beam through the lens. The position is changed, whereby the beam light can be bent accurately in accordance with the displacement of the movable roller, and the double feed detection according to the first invention can be performed with high accuracy.

In the sheet thickness detecting apparatus according to the third aspect of the present invention, the light beam irradiating means fixed to the interlocking rod interlocking with the movable roller directs the light beam toward the lens fixed to the apparatus body. After irradiating the light beam, this lens bends the optical axis of the light beam according to the transmission position of the light beam. The transmission position of the light beam in the lens is changed, whereby the light beam can be bent accurately in accordance with the displacement amount of the movable roller as in the second invention, and the double feed detection is performed with high accuracy It becomes possible.

In the sheet thickness detecting apparatus according to the fourth aspect of the present invention, the light beam can be bent in a specific direction by using a concave lens as the lens of the light beam bending means. Can be arranged at a specific position in the direction in which the light beam bends.

In the paper sheet thickness detecting apparatus according to the fifth invention, after the light beam irradiating means fixed to the apparatus main body irradiates the reflecting means fixed to the interlocking rod with the light beam, The reflecting mirror means reflects the light beam emitted from the light beam irradiating means, and further, a lens fixed to the interlocking rod together with the reflecting mirror means, the optical axis of the light beam according to the transmission position of the light beam. Are bent, the displacement of the reflecting mirror means in accordance with the movement of the movable roller changes the light beam transmission position in the lens, thereby displacing the movable roller in the same manner as in the second and third inventions. The light beam can be bent accurately according to the amount, and the double feed detection can be performed with high accuracy. Also,
By using such a reflecting mirror means, it is possible to set the light beam to be reflected in an arbitrary direction, thereby allowing a degree of freedom in the arrangement of the lens and the light receiving means. It is possible to easily cope with the case where the space is limited.
In the sheet thickness detecting device according to the sixth aspect of the present invention, since a prism is used as the reflecting mirror means, the light beam can be bent in an arbitrarily set direction by this prism. The means can be arranged at any position.

[Brief description of the drawings]

FIG. 1 shows a state in which there is no object in the first embodiment.

FIG. 2 is a front view showing the first embodiment, and shows a state in which normal paper sheets are sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 3 is a front view showing the first embodiment, and shows a state in which a double-feed sheet is sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 4 is a control block diagram of the first embodiment.

FIG. 5 is a front view showing a modification of the first embodiment, showing a state in which normal paper sheets are sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 6 is a front view showing a modified example of the first embodiment, and shows a state in which a double-feed sheet is sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 7 is a front view showing the second embodiment, and shows a state in which normal paper sheets are sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 8 is a front view showing the second embodiment, and shows a state in which a double-feed sheet is sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 9 is a front view showing a modification of the second embodiment, showing a state in which normal paper sheets are sandwiched between a fixed roller 2 and a movable roller 3.

FIG. 10 is a front view showing a modification of the second embodiment,
2 shows a state in which double-feed paper sheets are sandwiched between the fixed roller 2 and the movable roller 3.

FIG. 11 is a front view showing the third embodiment, and shows a state in which normal paper sheets are sandwiched between a fixed roller 2 and a movable roller 3;

FIG. 12 is a front view showing the third embodiment, and shows a state in which a double-feed sheet is sandwiched between a fixed roller 2 and a movable roller 3;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 paper sheet conveyance path 2 fixed roller 3 movable roller 5 interlocking rod 6 concave lens (beam light bending means) 7 light source (beam light irradiation means / beam light bending means) 8 light receiving element (light receiving means) 10 CPU 11 ROM 12 RAM 13 Discrimination circuit (thickness detection means) 15 Light source (beam light irradiation means / beam light bending means) 16 Concave lens (beam light bending means) 17 Convex lens (beam light bending means) 18 Convex lens (beam light bending means) 20 Triangular prism (reflection) Mirror means / beam light bending means) 21 Concave lens (beam light bending means) 50 Beam light 51 Lens axis 100 Device body S Paper

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-247895 (JP, A) JP-A-60-14397 (JP, A) JP-A-1-264872 (JP, A) JP-A-55-1979 48140 (JP, A) JP-A-6-180213 (JP, A) JP-A-57-60269 (JP, U) JP-T-63-501817 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G07D 7/00

Claims (6)

(57) [Claims] 1. A movable roller which is provided so as to be displaceable in a direction approaching and separating from a fixed roller, and sandwiches paper sheets with the fixed roller; a beam light irradiation means for irradiating a beam light; A beam bending unit having a lens that bends the optical axis of the beam emitted from the beam irradiating unit in accordance with the displacement of the movable roller; and a lens fixed to the apparatus body and passing through the lens of the beam bending unit. A light receiving unit that receives the light beam and outputs a detection signal indicating a light receiving position of the light beam; and detects a displacement amount of the movable roller based on the light receiving position of the light beam indicated by the detection signal from the light receiving unit. And a thickness detecting means for detecting the thickness of the sheet sandwiched between the fixed roller and the movable roller. 2. The light beam bending means is fixed to the apparatus main body and irradiates a light beam to a lens. The beam light irradiating means is fixed to a lens linked to the movable roller. The lens according to claim 1, further comprising: a lens that transmits the light beam emitted from the light irradiation means and that bends an optical axis of the light beam according to a transmission position of the light beam. Paper thickness detector. 3. The light beam bending means is fixed to an interlocking rod interlocking with a movable roller to irradiate a light beam to a lens. A lens that transmits the light beam emitted from the means and that bends the optical axis of the light beam according to the transmission position of the light beam;
2. The sheet thickness detecting device according to claim 1, wherein the sheet thickness detecting device comprises: 4. The method according to claim 1, wherein a concave lens is used as a lens of said beam light bending means.
The sheet thickness detecting device according to any one of the preceding claims. 5. The light beam bending means is fixed to the apparatus main body, and is fixed to a beam light irradiating means for irradiating the reflecting mirror means with a light beam; and an interlocking rod interlocked with the movable roller, A reflecting mirror means for reflecting the beam light emitted from the light beam irradiating means, and fixed to an interlocking rod together with the reflecting mirror means to transmit the light beam reflected by the reflecting mirror means, and in accordance with the transmission position thereof. A lens that bends the optical axis of the beam light,
The sheet thickness detecting device according to any one of claims 1 to 4, comprising: 6. A sheet thickness detecting apparatus according to claim 5, wherein a prism is used as said reflecting mirror means.