Medium conveying device and image reading apparatus

Abstract

The invention provides a medium conveying device and an image reading device, and the subject of the invention is that the distance from a transmission surface of ultrasonic waves to a protection part is very important from the perspective of multiple reflections of the ultrasonic waves, so that the distance is expected to be properly managed. The medium conveying device includes a first roller pair and an ultrasonic detection unit located downstream of the first roller pair. The ultrasonic detection unit is provided with: a transmission sensor chip that emits ultrasonic waves along a first axis; a reception sensor chip that is disposed at a position on the first axis and that receives the ultrasonic waves; a transmission substrate on which the transmission sensor chip is provided; and a reception substrate on which the reception sensor chip is provided. A first protective member positioned between the transmission sensor chip and the medium; a second protective member positioned between the reception sensor chip and the medium; a transmission substrate holder that holds the transmission substrate and the first protective member; and a reception substrate holder that holds the reception substrate and the second protective member.

Description

Technical Field

[0001] The present invention relates to a medium conveying device for conveying a medium, and an image reading device including the medium conveying device. Background Art

[0002] Conventionally, a technique for detecting overlapped feeding of a medium using an ultrasonic sensor as disclosed in Patent Document 1 has been used.

[0003] The ultrasonic device described in Patent Document 1 is provided with a protective member covering the ultrasonic element in order to suppress the accumulation of foreign matter such as paper dust on the ultrasonic transmission and reception surface.

[0004] As described in Patent Document 1 Figure 6 As shown, the distance from the ultrasonic transmission surface to the protective member is very important from the viewpoint of multiple reflections of ultrasonic waves, and it is desirable to appropriately manage the distance.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-25242 Summary of the invention

[0006] The medium conveying device of the present invention for solving the above-mentioned problems is characterized in that it comprises: a first roller pair that conveys the medium in a conveying direction; an ultrasonic detection unit that is arranged downstream of the first roller pair in the conveying direction, and in the medium conveying device, the ultrasonic detection unit comprises: a transmitting sensor chip that emits ultrasonic waves along a first axis toward a first surface of the medium being conveyed; a receiving sensor chip that is arranged at a position on the first axis with the medium between the transmitting sensor chip and receives the ultrasonic waves; a transmitting substrate on which the transmitting sensor chip is provided; a receiving substrate on which the receiving sensor chip is provided; a first protective component that is a protective component arranged on the first axis and is located between the transmitting sensor chip and the medium; a second protective component that is a protective component arranged on the first axis and is located between the receiving sensor chip and the medium; a transmitting substrate bracket that holds the transmitting substrate and the first protective component; and a receiving substrate bracket that holds the receiving substrate and the second protective component.

[0007] Furthermore, the image reading device of the present invention is characterized by comprising: the medium conveying device; and a reading section which is located downstream of the second roller pair in the conveying direction and reads the image of the medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a stereoscopic view of the scanner as viewed from the front.

[0009] Figure 2 This is a diagram of the document transport path of the scanner as viewed from the width direction.

[0010] Figure 3 is a block diagram showing a control system of a scanner.

[0011] Figure 4 This is a perspective view showing a state in which the second unit is opened relative to the first unit.

[0012] Figure 5 This is the floor plan of the first unit.

[0013] Figure 6 This is a perspective view of a state where the cover to be mounted on the first unit is mounted.

[0014] Figure 7 This is a perspective view showing a state in which the cover mounted on the first unit is removed.

[0015] Figure 8 This is a perspective view of the first unit as viewed from the back side.

[0016] Fig. 9 It is a perspective view showing the fixed state of the sending substrate holder.

[0017] Fig.10 This is the floor plan of the second unit.

[0018] Fig.11 It is a perspective view showing the fixed state of the receiving substrate holder.

[0019] Fig.12 It is a perspective view showing the positional relationship among the first roller pair, the second roller pair, the third roller pair, and the ultrasonic detection unit.

[0020] Fig.13 This is a three-dimensional diagram of the ultrasonic detection unit.

[0021] Fig.14 This is a three-dimensional diagram of the ultrasonic detection unit.

[0022] Fig.15 A perspective view of the transmitting substrate.

[0023] Fig.16 A side view of the transmitting substrate.

[0024] Fig.17 A perspective view of the transmitting substrate support.

[0025] Fig.18 A perspective view of the transmitting substrate support.

[0026] Fig.19 A perspective view of the protective components.

[0027] Fig. 20 This is an enlarged plan view of the protective components.

[0028] Fig.21 It is a cross-sectional view showing the structure of the transmitting sensor chip.

[0029] Fig. 22 It is a cross-sectional view showing the structure of the ultrasonic detection unit.

[0030] Fig.23 It is a figure which shows the positional relationship between the ultrasonic detection part and the 1st roller pair.

[0031] Fig.24 It is a diagram showing the positional relationship between the ultrasonic detection unit and the second roller pair or the third roller pair.

[0032] Fig.25 It is a figure which shows the structure of a 2nd roller pair.

[0033] Fig.26 It is a cross-sectional perspective view showing the structure of the first reading unit.

[0034] Fig. 27 FIG. 2 is a diagram showing the positional relationship between the sensor substrate of the first reading unit, the transmitting sensor chip, and the transmitting substrate.

[0035] Fig.28 FIG. 2 is a diagram showing the positional relationship between the second reading unit, the receiving sensor chip, and the receiving substrate.

[0036] Fig.29 The figure shows the occupied areas of the first roller pair, the second roller pair, the transport motor, the transmission sensor chip, the transmission substrate, the reception sensor chip, and the reception substrate. DETAILED DESCRIPTION

[0037] Hereinafter, the present invention will be schematically described.

[0038] The medium conveying device involved in the first embodiment is characterized in that it comprises: a first roller pair that conveys the medium in a conveying direction; an ultrasonic detection unit that is arranged downstream of the first roller pair in the conveying direction, and in the medium conveying device, the ultrasonic detection unit comprises: a transmitting sensor chip that emits ultrasonic waves along a first axis toward a first surface of the conveyed medium; a receiving sensor chip that is arranged at a position on the first axis and separated from the transmitting sensor chip by the medium and receives ultrasonic waves; a transmitting substrate on which the transmitting sensor chip is provided; a receiving substrate on which the receiving sensor chip is provided; a first protective component that is a protective component arranged on the first axis and is located between the transmitting sensor chip and the medium; a second protective component that is a protective component arranged on the first axis and is located between the receiving sensor chip and the medium; a transmitting substrate bracket that holds the transmitting substrate and the first protective component; and a receiving substrate bracket that holds the receiving substrate and the second protective component.

[0039] According to this aspect, since the transmission substrate and the first protective member are provided on the transmission substrate holder, it is possible to suppress the variation in the distance between the transmission sensor chip and the first protective member. As a result, it is possible to appropriately suppress multiple reflections of ultrasonic waves between the transmission substrate and the first protective member.

[0040] Furthermore, since the receiving substrate and the second protective component are disposed on the receiving substrate holder, it is possible to suppress the deviation of the distance between the receiving sensor chip and the second protective component. As a result, it is possible to appropriately suppress multiple reflections of ultrasonic waves between the receiving sensor chip and the second protective component.

[0041] The second method is a method subordinate to the first method, and is characterized in that the sending substrate holder has a first opening, the first opening allows ultrasonic waves to pass through on the first axis, the first protective component is arranged in a manner to cover the first opening on the surface of the sending substrate holder, the receiving substrate holder has a second opening, the second opening allows ultrasonic waves to pass through on the first axis, and the second protective component is arranged in a manner to cover the second opening on the surface of the receiving substrate holder.

[0042] If foreign matter remains attached to the first protective member or the second protective member, the intensity of the ultrasonic wave received by the receiving sensor chip may be reduced, resulting in a possibility of erroneous detection. Therefore, in this case, the first protective member or the second protective member needs to be replaced or cleaned.

[0043] According to this method, since the transmitting substrate holder has a first opening that allows ultrasonic waves to pass through on the first axis, and the first protective component is arranged on the surface of the transmitting substrate holder to cover the first opening, replacement and maintenance of the first protective component are easier.

[0044] In addition, since the receiving substrate holder has a second opening that allows ultrasonic waves to pass through the first axis, and the second protective component is arranged on the surface of the receiving substrate holder to cover the second opening, replacement and maintenance of the second protective component are easier.

[0045] The third method is a method subordinate to the first method, and is characterized in that the transmitting sensor chip and the receiving sensor chip are inclined at a first angle relative to the surface of the medium passing between the transmitting sensor chip and the receiving sensor chip, the first protective component and the second protective component are inclined at a second angle relative to the surface of the medium passing between the transmitting sensor chip and the receiving sensor chip, the first angle is different from the second angle, and the second angle is gentler than the first angle.

[0046] When the first protective component and the second protective component are parallel to the surface of the medium passing between the sending sensor chip and the receiving sensor chip, paper dust and the like are easily attached to the first protective component and the second protective component. However, since the first protective component and the second protective component are inclined at a second angle relative to the surface of the medium passing between the sending sensor chip and the receiving sensor chip, the attachment of foreign matter such as paper dust and the like to the first protective component and the second protective component can be suppressed.

[0047] In addition, since the transmitting sensor chip and the receiving sensor chip are inclined at a first angle relative to the surface of the medium passing between the transmitting sensor chip and the receiving sensor chip, multiple reflections of ultrasonic waves between the transmitting sensor chip and the medium or between the receiving sensor chip and the medium can be suppressed.

[0048] Furthermore, since the first angle and the second angle are different, multiple reflections of ultrasonic waves between the transmitting sensor chip and the first protective member can be suppressed, and multiple reflections of ultrasonic waves between the receiving sensor chip and the second protective member can be suppressed.

[0049] In addition, this aspect is not limited to being subordinate to the above-mentioned first aspect, and may be subordinate to the above-mentioned second aspect.

[0050] The fourth method is a method subordinate to the first method, and is characterized in that it comprises: a second roller pair, which is arranged downstream of the first roller pair in the conveying direction; a sending side path forming component, which is a component that forms the medium conveying path between the first roller pair and the second roller pair and fixes the sending substrate holder, the first roller pair includes a separation roller, the separation roller is in contact with the first surface of the medium, and a detachable cover is provided on the sending side path forming component, when the cover is installed, the sending substrate holder will be covered by the cover, when the cover is removed, the separation roller can be replaced, and the sending substrate holder will be visible.

[0051] According to this aspect, when the cover is removed, the separation roller can be replaced and the sending substrate holder is exposed, so that the sending substrate holder can be easily accessed. As a result, for example, replacement and maintenance of the first protective member are facilitated.

[0052] In addition, this aspect is not limited to being subordinate to the above-mentioned first aspect, and may be subordinate to the above-mentioned second or third aspect.

[0053] The fifth method is a method subordinate to the first method, and is characterized in that the sending substrate bracket has a fixing portion, the fixing portion fixes the first protective component, the sending substrate is fixed on the inner side of the fixing portion, and the fixing portion has a wall portion, which is a wall portion opposite to the side of the fixed sending substrate and covers at least a portion of the sending substrate.

[0054] According to this method, since the sending substrate bracket has a fixing portion, the fixing portion fixes the first protective component, the sending substrate is fixed on the inner side of the fixing portion, and the fixing portion has a wall portion, which is a wall portion opposite to the side of the fixed sending substrate and covers at least a portion of the sending substrate. Therefore, when foreign matter attempts to bypass the side of the fixing portion to reach the sending substrate, the foreign matter can be blocked by the wall portion.

[0055] In addition, this aspect is not limited to being subordinate to the above-mentioned first aspect, and may be subordinate to any one of the above-mentioned second to fourth aspects.

[0056] A sixth aspect is an aspect dependent on the first aspect, and is characterized in that the first protection member and the second protection member are mesh-shaped members.

[0057] According to this aspect, since the first protective member and the second protective member are mesh-shaped members, ultrasonic waves can be allowed to pass through the first protective member and the second protective member in a good manner.

[0058] In addition, this aspect is not limited to being subordinate to the above-mentioned first aspect, and may be subordinate to any one of the above-mentioned second to fifth aspects.

[0059] A seventh aspect is an aspect dependent upon the sixth aspect, and is characterized in that the opening width of the grid-like member is 30 μm or less.

[0060] According to this embodiment, since the opening width of the grid-shaped member is 30 μm or less, when the device is cleaned with a cleaning agent, it is possible to suppress the cleaning agent from passing through the first protective member and adhering to the transmitting sensor chip, or the cleaning agent from passing through the second protective member and adhering to the receiving sensor chip. As a result, it is possible to suppress the undesirable situation that the intensity of the ultrasonic wave received by the receiving sensor chip is reduced and causes erroneous detection.

[0061] The eighth method is a method subordinate to the first method, and is characterized in that a first enclosing component is provided on the sending substrate, the first enclosing component is a component that encloses the sending sensor chip, and is a plate-shaped component provided along the sending substrate, and a second enclosing component is provided on the receiving substrate, the second enclosing component is a component that encloses the receiving sensor chip, and is a plate-shaped component provided along the receiving substrate.

[0062] According to this method, since a first enclosing component is provided on the sending substrate, the first enclosing component is a component that encloses the sending sensor chip and is a plate-shaped component provided along the sending substrate, and a second enclosing component is provided on the receiving substrate, the second enclosing component is a component that encloses the receiving sensor chip and is a plate-shaped component provided along the receiving substrate, the sending sensor chip or the receiving sensor chip can be protected from external forces.

[0063] In addition, this aspect is not limited to being subordinate to the above-mentioned first aspect, and may be subordinate to any one of the above-mentioned second to seventh aspects.

[0064] An image reading device according to a ninth aspect includes: the medium conveying device according to any one of the first to eighth aspects; and a reading unit that is located downstream of the first roller pair in the conveying direction and reads an image on the medium.

[0065] According to this aspect, in the image reading device, the operational effects of any one of the first to eighth aspects described above can be obtained.

[0066] Hereinafter, the present invention will be described in detail.

[0067] Hereinafter, as an example of an image reading device, a scanner 1 is cited as an example that can read at least one of a first surface S1 and a second surface S2 opposite to a document P as an example of a medium. The scanner 1 is a so-called sheet-feed type scanner that reads the document P while moving it relative to a first reading unit 32 and a second reading unit 33 described later.

[0068] In this specification, it is assumed that the document P includes not only a sheet-shaped document but also a card-shaped document and a booklet-shaped document.

[0069] The scanner 1 can be understood as a medium transport device 100 from the viewpoint of transporting a document P, which is an example of a medium. In this case, the scanner 1 is configured to include the medium transport device 100 and a first reading unit 32 and a second reading unit 33 described later.

[0070] In the XYZ coordinate system shown in the drawings, the X-axis direction is the device width direction and also the document width direction, the Y-axis direction is the device depth direction, and the Z-axis direction is the direction along the vertical direction.

[0071] In this embodiment, the +Y direction is set to the direction from the back of the device to the front, and the -Y direction is set to the direction from the front of the device to the back. In addition, when observing from the front of the device, the left direction is set to the +X direction, and the right direction is set to the -X direction.

[0072] In addition, hereinafter, the direction in which the document P is conveyed may be referred to as “downstream”, and the direction opposite to this direction may be referred to as “upstream”.

[0073] Scanner Overview

[0074] exist Figure 1 In the embodiment, the scanner 1 includes a device body 2 and a body support portion 6 that supports the device body 2. The body support portion 6 is placed on a placement surface GS of the device. As an example, the placement surface GS is a surface parallel to a horizontal plane.

[0075] The device main body 2 is configured to include a first unit 3 , a second unit 4 , and a third unit 5 .

[0076] The second unit 4 and the third unit 5 are rotatable relative to the first unit 3 about a rotation axis (not shown) parallel to the X-axis direction. The second unit 4 and the third unit 5 are integrally rotatable relative to the first unit 3 about the rotation axis. Figure 1 The symbol 8a in the figure indicates a lock release portion. The user can release the lock of the second unit 4 and the third unit 5 relative to the first unit 3 by sliding the lock release portion 8a in the -X direction. In addition, by rotating the second unit 4 and the third unit 5 relative to the first unit 3, a part of the document conveying path can be exposed (see Figure 4 ). In particular, by opening the second unit 4 relative to the first unit 3, the upstream feeding path R0, the downstream feeding path R1, and the reading and conveying path R2 described later can be made visible.

[0077] In addition, the third unit 5 can rotate relative to the first unit 3 and the second unit 4 about a rotation axis parallel to the X-axis direction (not shown). By rotating the third unit 5 relative to the second unit 4, the reading conveying path R2 described later can be turned to the downstream U-turn discharge path R3 (see Figure 2 That is, a U-turn discharge path R3 is formed between the third unit 5 and the second unit 4.

[0078] The third unit 5 is held relative to the second unit 4 by an engaging structure (not shown), and the user applies an external force to the third unit 5 to release the holding of the third unit 5 relative to the second unit 4, thereby enabling the third unit 5 to be opened.

[0079] The device body 2 can be rotated relative to the body support portion 6 about the body rotation axis 6c (see Figure 2 ) is rotated as the center. In the present embodiment, the device body 2 can maintain two postures by rotating. Figure 2 The posture of the device body 2 shown is one of the two postures, and is a normal reading posture. In addition, the device body 2 can be rotated from the normal reading posture so that the reading conveying path R2 is nearly horizontal, thereby obtaining a booklet reading posture (not shown).

[0080] exist Figure 1 In the embodiment, an operation unit 7 composed of a plurality of operation buttons is provided on the front of the device. In the present embodiment, the plurality of operation buttons are composed of operation buttons 7a, 7b, and 7c, and user operations are accepted through these buttons.

[0081] Scanner document feeding path

[0082] Next, refer to Figure 2Next, the document transport path in the scanner 1 will be described. Figure 2 In FIG. 1 , a thick dotted line indicates a conveyance path along which the document P is conveyed.

[0083] Reference numeral R0 denotes a conveying path upstream of the first roller pair 13 , and this conveying path is hereinafter referred to as an upstream feeding path R0 .

[0084] Symbol R1 is a conveying path between the first roller pair 13 and the second roller pair 16 , and hereinafter, this conveying path is referred to as a downstream feeding path R1 .

[0085] Reference numeral R2 denotes a conveyance path between the second roller pair 16 and the third roller pair 20, and this conveyance path is hereinafter referred to as a reading conveyance path R2. The reading conveyance path R2 is a conveyance path facing a first reading unit 32 and a second reading unit 33 described later.

[0086] The first unit 3 constitutes the lower side of the upstream feeding path R0 , the downstream feeding path R1 , and the reading conveying path R2 , and the second unit 4 constitutes the upper side of the upstream feeding path R0 , the downstream feeding path R1 , and the reading conveying path R2 .

[0087] In addition, symbol R3 is a conveying path which is reversed upward from the third roller pair 20 , and this conveying path is hereinafter referred to as a U-turn discharge path R3 . The U-turn discharge path R3 is formed between the second unit 4 and the third unit 5 .

[0088] The normal reading posture of the device body 2 ( Figure 2 ) is a posture in which the reading conveying path R2 is connected to the U-turn discharge path R3 through the baffle 35. In addition, in the booklet reading posture (not shown) of the device body 2, the baffle 35 is in the posture shown by the double-dashed line, and the reading conveying path R2 is not connected to the U-turn discharge path R3, and the original P is discharged from the reading conveying path R2 in an oblique downward direction including a +Y direction component and a -Z direction component.

[0089] The normal reading posture is suitable for reading a thin sheet of original document P, that is, a relatively low-rigidity original document P that is easily bent. The booklet reading posture is suitable for reading a relatively high-rigidity original document P such as a plastic card or booklet that is not easily bent.

[0090] The document conveying path is further described below. The document P being fed is supported in an inclined posture by the document support portion 11 and the document support member 9. When a plurality of documents P are supported on the document support portion 11, the document P located at the top is fed downstream by the feed roller 14. The document support portion 11 is formed on the upper opening and closing portion 10. The upper opening and closing portion 10 can rotate around a rotation axis (not shown) as the center, and the feed port is opened and closed by the rotation.

[0091] The document support 9 can be placed in a state accommodated in the upper opening and closing portion 10 or in a state extended from the upper opening and closing portion 10 . Figure 1 Indicates the state where the upper opening and closing portion 10 is closed. Figure 2 The upper opening and closing section 10 is opened and the document support member 9 is unfolded. The upper opening and closing section 10 and the document support member 9 constitute the first unit 3.

[0092] The scanner 1 adopts a so-called center feed method, and the center position of the document P in the X-axis direction, that is, the width direction, is consistent regardless of the size of the document P.

[0093] The feed roller 14 and the separation roller 15 constitute a first roller pair 13 .

[0094] The feed roller 14 is provided in the second unit 4. The feed roller 14 is driven by a conveying motor 47 (refer to Figure 3 ) obtains power and rotates. A separation roller 15 is provided at a position opposite to the feed roller 14 in the first unit 3. The separation roller 15 is connected to a torque limiter 15b (see Figure 6 ) and a rotational torque is applied to suppress the double feeding of the original P.

[0095] In addition, although in the present embodiment, the feeding roller 14 is provided at the upper side relative to the original P placed on the original support portion 11, and the feeding is performed from the top original P, it may also be provided at the lower side relative to the original P placed on the original support portion 11, and the feeding is performed from the bottom original P.

[0096] The ultrasonic detection unit 50 is provided on the downstream feeding path R1 downstream of the first roller pair 13. The ultrasonic detection unit 50 is configured to include a transmitting unit 50A and a receiving unit 50B which are arranged to face each other across the downstream feeding path R1. Figure 3 ) The double feeding of the original P can be detected by the signal transmitted from the receiving unit 50B.

[0097] In addition, Figure 2In the figure, the position, size, and shape of the transmitting unit 50A and the receiving unit 50B are conceptually represented, and the details thereof will be used later. Figure 4 The following drawings will be described again.

[0098] In addition, although in the present embodiment, the sending unit 50A is configured at the lower side of the downstream feeding path R1 and the receiving unit 50B is configured at the upper side of the downstream feeding path R1, it is not limited to this, and the receiving unit 50B may be configured at the lower side of the downstream feeding path R1 and the sending unit 50A may be configured at the upper side of the downstream feeding path R1.

[0099] A second roller pair 16 is provided downstream of the feed roller 14 and the separation roller 15. The second roller pair 16 is composed of a second lower roller 17 provided in the first unit 3 and a second upper roller 18 provided in the second unit 4. The second upper roller 18 is provided so as to be able to advance and retreat relative to the second lower roller 17, and is pressed toward the second lower roller 17 by a pressing member (not shown), such as a coil spring. Thus, the second upper roller 18 advances and retreats relative to the second lower roller 17 according to the thickness of the document P being conveyed.

[0100] The second lower roller 17 and the second upper roller 18 are driven together by the conveying motor 47 (see Figure 3 ) obtains power and rotates.

[0101] When the second unit 4 is closed relative to the first unit 3, the second lower roller 17 is in contact with the second upper roller 18. When the second unit 4 is opened relative to the first unit 3, the second upper roller 18 is separated from the second lower roller 17.

[0102] A first reading section 32 and a second reading section 33 are disposed opposite to each other at a downstream of the second roller pair 16. The first reading section 32 is provided in the first unit 3, and the second reading section 33 is provided in the second unit 4.

[0103] The first reading section 32 reads the first surface S1, which is the lower surface of the document P supported on the document support section 11, and the second reading section 33 reads the second surface S2, which is the upper surface of the document P supported on the document support section 11. The second reading section 33 is provided so as to be able to advance and retreat relative to the first reading section 32, and is pressed toward the first reading section 32 by a pressing spring 34, which is an example of a pressing member. Thus, the second reading section 33 advances and retreats relative to the first reading section 32 according to the thickness of the document P being fed.

[0104] In the present embodiment, the first reading section 32 and the second reading section 33 are configured by a contact image sensor module (CISM).

[0105] A third roller pair 20 is provided downstream of the first reading section 32 and the second reading section 33. The third roller pair 20 is composed of a third lower roller 21 provided in the first unit 3 and a third upper roller 22 provided in the second unit 4. The third upper roller 22 is provided so as to be able to advance and retreat relative to the third lower roller 21, and is pressed toward the third lower roller 21 by a pressing member (not shown), such as a coil spring.

[0106] The third lower roller 21 and the third upper roller 22 are driven together by the conveying motor 47 (see Figure 3 ) obtains power and rotates.

[0107] When the second unit 4 is closed relative to the first unit 3, the third lower roller 21 is in contact with the third upper roller 22. When the second unit 4 is opened relative to the first unit 3, the third upper roller 22 is separated from the third lower roller 21.

[0108] A flapper 35 is provided downstream of the third roller pair 20. The flapper 35 switches the document conveyance path as described above by rotating.

[0109] In addition, in the present embodiment, the baffle 35 is configured to rotate in conjunction with the posture switching of the device body 2. As a structure for rotating the baffle 35 in conjunction with the posture switching of the device body 2, in the present embodiment, a structure is set to rotate mechanically in conjunction with the posture of the device body 2 through a linkage mechanism not shown, such as a cam mechanism. However, the baffle 35 may also be a structure that rotates through a solenoid not shown. In this case, the control unit 80 (refer to Figure 3 ) The solenoid is driven based on the detection information of the posture detection sensor (not shown) to rotate the baffle 35.

[0110] On the U-turn discharge path R3, a fourth roller pair 24 and a fifth roller pair 28 are provided.

[0111] The fourth roller pair 24 is composed of a fourth driving roller 25 provided in the third unit 5 and a fourth driven roller 26 provided in the second unit 4. The fourth driven roller 26 is provided so as to be able to move forward and backward relative to the fourth driving roller 25, and is pressed toward the fourth driving roller 25 by a pressing member (not shown), such as a coil spring. Thus, the fourth driven roller 26 moves forward and backward relative to the fourth driving roller 25 according to the thickness of the document P being conveyed. The fourth driving roller 25 is driven by a conveying motor 47 (see Figure 3 ) is driven. The fourth driven roller 26 is a roller that performs driven rotation.

[0112] The fifth roller pair 28 is composed of a fifth driving roller 29 provided in the third unit 5 and a fifth driven roller 30 provided in the second unit 4. The fifth driven roller 30 is provided so as to be able to move forward and backward relative to the fifth driving roller 29, and is pressed toward the fifth driving roller 29 by a pressing member (not shown), such as a coil spring. Thus, the fifth driven roller 30 moves forward and backward relative to the fifth driving roller 29 according to the thickness of the document P being transported. The fifth driving roller 29 is driven by a transport motor 47 (see Figure 3 ) is driven. The fifth driven roller 30 is a roller that performs driven rotation.

[0113] When the third unit 5 is closed relative to the second unit 4, the fourth driving roller 25 contacts the fourth driven roller 26, and the fifth driving roller 29 contacts the fifth driven roller 30. When the third unit 5 is opened relative to the second unit 4, the fourth driving roller 25 separates from the fourth driven roller 26, and the fifth driving roller 29 separates from the fifth driven roller 30.

[0114] The document P discharged from the U-turn discharge path R3 is discharged obliquely upward including a −Y direction component by the fifth roller pair 28 , and is supported in an inclined posture by the upper surface 4 a of the second unit 4 .

[0115] In addition, Figure 2 , the direction indicated by the arrow mark Da1 represents the normal direction of the first surface S1 and the second surface S2 opposite to the original P at the original clamping position of the first roller pair 13. In addition, since the first surface S1 and the second surface S2 opposite to the original P are parallel in most cases, they are collectively referred to as the original surface S in the following text without distinguishing between them.

[0116] In addition, an arrow mark Da2 indicates the direction of a normal line with respect to the document surface S of the document P passing between the transmission unit 50A and the reception unit 50B of the ultrasonic detection unit 50 .

[0117] Furthermore, an arrow mark Da3 indicates the normal direction with respect to the document surface S at the document gripping position of the second roller pair 16 .

[0118] In addition, an arrow mark Da4 indicates the normal direction with respect to the document surface S of the document P passing between the first reading section 32 and the second reading section 33 .

[0119] Furthermore, an arrow mark Da5 indicates the normal direction with respect to the document surface S at the document gripping position of the third roller pair 20 .

[0120] In this embodiment, since the differences among the normal directions Da1, Da2, Da3, Da4, and Da5 are relatively subtle, as an example, the difference between the maximum angle and the minimum angle is within 5°, in the following text, the normal direction is referred to as the normal direction Da without distinguishing between the normal directions.

[0121] In addition, Figure 2 In FIG. 1 , the direction indicated by the arrow mark Fp is a direction perpendicular to the normal direction Da, and indicates the direction in which the document P is conveyed. Hereinafter, this direction is referred to as a conveyance direction Fp.

[0122] In addition, Figure 4 In the following drawings, the X-Fp-Da coordinate system is used depending on the situation.

[0123] Scanner control system

[0124] Next, refer to Figure 3 Next, the control system of the scanner 1 will be described.

[0125] The control unit 80 includes a calculation unit 81 formed of a CPU (Central Processing Unit) or the like, and a storage unit 85 formed of a nonvolatile memory or a volatile memory.

[0126] The control unit 80 is connected to the first reading unit 32, the second reading unit 33, the conveying motor 47, and the ultrasonic detection unit 50, and controls these components. The conveying motor 47 is a driving source for the feed roller 14, the second lower roller 17, the second upper roller 18, the third lower roller 21, the third upper roller 22, the fourth drive roller 25, and the fifth drive roller 29.

[0127] The control unit 80 is connected to the interface unit 86 to receive various data and signals input from an external device 87 such as a personal computer or output the read data read by the scanner 1 to the external device 87 .

[0128] Various data and various programs for controlling the scanner 1 are recorded in the storage unit 85 .

[0129] The calculation unit 81 reads and executes various programs stored in the storage unit 85 , thereby functioning as a conveyance control unit 82 , a reading control unit 83 , a double-feed determination unit 84 , and the like.

[0130] The conveyance control unit 82 controls the conveyance motor 47 to rotate the plurality of rollers described above, thereby performing feeding, conveyance, and discharge of the document P.

[0131] The reading control unit 83 controls the first reading unit 32 and the second reading unit 33 during the conveyance of the document P, thereby causing these reading units to read the image of the document P.

[0132] The duplicate feed determination unit 84 is a state detection unit that detects the state of the document P, and in the present embodiment, determines duplicate feed of the document P based on a reception signal input from a reception circuit 59 (described later).

[0133] Specifically, when the voltage value of the reception signal is smaller than a predetermined threshold, it is determined that the document P is double-fed. When the double-feed determination unit 84 determines that double-feeding has occurred, the transport control unit 82 stops transporting the document P.

[0134] Basic structure of ultrasonic detection unit

[0135] Next, the basic structure of the ultrasonic detection unit 50 will be described.

[0136] exist Fig. 22 In the embodiment, the ultrasonic detection unit 50 is configured to include a pair of ultrasonic elements. One of the pair of ultrasonic elements is a transmitting sensor chip 53, which transmits ultrasonic waves. The other of the pair of ultrasonic elements is a receiving sensor chip 56, which receives ultrasonic waves.

[0137] The transmission sensor chip 53 and the reception sensor chip 56 are arranged to face each other on a sensor center axis Lx, which is an example of a first axis, and to sandwich the document P conveyed on the downstream feeding path R1 .

[0138] In the ultrasonic detection unit 50, ultrasonic waves are emitted from the transmitting sensor chip 53 toward the first surface S1 of the fed document P. The ultrasonic waves emitted from the transmitting sensor chip 53 are input to the document P, and the ultrasonic waves transmitted through the document P are received by the receiving sensor chip 56. When the ultrasonic waves are received by the receiving sensor chip 56, a reception signal corresponding to the sound pressure of the received ultrasonic waves is output, and duplicate feeding of the document P is determined based on the signal strength of the reception signal.

[0139] The sensor center axis Lx is an axis passing through the center of the transmitting sensor chip 53 and the center of the receiving sensor chip 56, and is the transmission and reception direction of the ultrasonic wave. The sensor center axis Lx is orthogonal to the transmitting surface 53a which is the upper surface of the transmitting sensor chip 53 and the receiving surface 56a which is the upper surface of the receiving sensor chip 56.

[0140] Furthermore, the sensor central axis Lx is inclined with respect to the document surface S of the document P at an angle β.

[0141] Here, when the sensor center axis Lx is aligned with the normal direction of the document surface S, that is, when the angle β=90°, there is a possibility that the ultrasonic wave transmitted from the transmitting sensor chip 53 is multiply reflected between the document P and the transmitting sensor chip 53. In addition, there is a possibility that the ultrasonic wave that has passed through the document P is multiply reflected between the receiving sensor chip 56 and the document P. In this case, in addition to the ultrasonic wave that has passed through the document P from the transmitting sensor chip 53 and is received by the receiving sensor chip 56, the ultrasonic wave that has been multiply reflected between the document P and the transmitting sensor chip 53 and the ultrasonic wave that has been multiply reflected between the receiving sensor chip 56 and the document P are received by the receiving sensor chip 56, resulting in failure to perform accurate double-feed detection.

[0142] In contrast, by tilting the sensor center axis Lx relative to the normal line of the document surface S of the document P, reception of unnecessary ultrasonic components such as multiply reflected ultrasonic waves can be reduced, thereby enabling accurate double feed detection.

[0143] The angle β can be set to 60° to 80°, and is set to 70° in the present embodiment.

[0144] In addition, when the area of ​​the transmitting surface 53a of the transmitting sensor chip 53 is small, the beam diameter of the ultrasonic wave will become smaller. In this case, if the distance between the transmitting sensor chip 53 and the receiving sensor chip 56, that is, the distance along the sensor center axis Lx, is short, the sound pressure drop of the ultrasonic wave when the transmitting sensor chip 53 deviates from the sensor center axis Lx will increase due to the installation error. In the case where the area of ​​the receiving surface 56a of the receiving sensor chip 56 is small, the sound pressure drop when it deviates from the sensor center axis Lx will also increase. Therefore, although it is preferable to ensure the distance between the transmitting sensor chip 53 and the receiving sensor chip 56 to a certain extent, if the distance between the transmitting sensor chip 53 and the receiving sensor chip 56 is too long, this will also cause a sound pressure drop.

[0145] In this embodiment, in view of the above viewpoint, the distance between the transmitting sensor chip 53 and the receiving sensor chip 56 along the sensor central axis Lx, that is, the sensor pitch is set to a range of 15.0 mm to 30.0 mm, and is set to 24.9 mm as an example.

[0146] Sensor chip structure

[0147] The structure of the ultrasonic detection unit 50 will be further described.

[0148] like Figure 3 As shown, a transmission circuit 58 for controlling the transmission sensor chip 53 is provided on the transmission substrate 52 , and a reception circuit 59 for controlling the reception sensor chip 56 is provided on the reception substrate 55 .

[0149] Here, refer to Fig.21 , to illustrate the structure of the sending sensor chip 53.

[0150] The transmission sensor chip 53 is configured to include a base substrate 213 , an element substrate 210 , and a piezoelectric element 220 .

[0151] The element substrate 210 includes a substrate body 211 and a vibration plate 212 provided on one side of the substrate body 211. Here, in the following description, the substrate thickness direction of the element substrate 210 is referred to as the G direction. The G direction is the direction in which ultrasonic waves are transmitted and is parallel to the sensor center axis Lx.

[0152] The substrate body 211 is a substrate provided on the vibration plate 212 and is formed of a semiconductor substrate such as Si. The substrate body 211 is provided with an opening 211A penetrating the substrate body 211 along the G direction.

[0153] The vibration plate 212 is supported by the base substrate 213. The vibration plate 212 and the base substrate 213 are bonded and fixed. Between the base substrate 213 and the vibration plate 212, a space for arranging the piezoelectric element 220 is provided.

[0154] In addition, the vibration plate 212 only needs to be fixed in a state of being laminated on the base substrate 213 .

[0155] The vibration plate 212 is made of SiO2 or a laminate of SiO2 and ZrO2, and is provided on the -G side of the substrate main body 211. The vibration plate 212 blocks the -G side of the opening 211A. The portion of the vibration plate 212 that overlaps the opening 211A when viewed from the G direction constitutes the vibration portion 212A.

[0156] The piezoelectric element 220 is provided on the vibration plate 212 at a position overlapping with each vibration portion 212A when viewed from the G direction. The piezoelectric element 220 is configured by laminating a first electrode 221 , a piezoelectric film 222 , and a second electrode 223 in this order on the vibration plate 212 .

[0157] Here, one ultrasonic transducer Tr is formed by one vibration part 212A and the piezoelectric element 220 provided on the vibration part 212A. Although not shown in the figure, in the present embodiment, such ultrasonic transducers Tr are arranged in a two-dimensional array structure to form a transmitting sensor chip 53. The transmitting circuit 58 (see Figure 3 ) is electrically connected to each ultrasonic transducer Tr of the transmitting sensor chip 53, and generates a driving signal for driving each ultrasonic transducer Tr.

[0158] The transmitting sensor chip 53 applies a pulse wave voltage of a predetermined frequency between the first electrode 221 and the second electrode 223 of each ultrasonic transducer Tr, thereby causing the piezoelectric film 222 to expand and contract. As a result, the vibration part 212A vibrates at a frequency corresponding to the opening width of the opening part 211A, and ultrasonic waves are transmitted from the vibration part 212A toward the +G side along the sensor center axis Lx. In other words, the surface on the +G side of the element substrate 210 becomes the ultrasonic transmission surface 53a of the transmitting sensor chip 53.

[0159] In addition, the base substrate 213 of the transmission sensor chip 53 is adhered to the transmission substrate 52 via a resist using a non-conductive adhesive. In addition, at least one of a chip tilt prevention pad (not shown) for preventing the transmission sensor chip 53 from tilting relative to the transmission substrate 52, a positioning mark portion (not shown) for the transmission sensor chip 53 relative to the transmission substrate 52, and an adhesive leakage suppression portion (not shown) for preventing the non-conductive adhesive from overflowing is provided on the transmission substrate 52. The transmission sensor chip 53 is attached to the transmission substrate 52 using silver solder paste at a position different from the chip tilt prevention pad (not shown), and the chip tilt prevention pad (not shown) is not used for conduction.

[0160] In addition, although the structure of the receiving sensor chip 56 is omitted from the figure, the receiving sensor chip 56 has the same structure as the transmitting sensor chip 53 described above. In this case, the surface on the +G side of the element substrate 210 becomes the receiving surface 56a of the ultrasonic wave of the receiving sensor chip 56. When the ultrasonic wave reaches the ultrasonic transducer Tr, the vibration plate 212 vibrates according to the sound pressure of the ultrasonic wave. The vibrating piezoelectric film 222 of the vibration plate 212 is deformed, thereby generating a potential difference between the first electrode 221 and the second electrode 223. As a result, a reception signal corresponding to the sound pressure of the received ultrasonic wave is output from the first electrode 221 of the ultrasonic transducer Tr. In other words, the ultrasonic wave is detected.

[0161] The receiving circuit 59 ( Figure 3), a general circuit for processing a reception signal input by receiving ultrasonic waves can be used. For example, the reception circuit 59 can be composed of a bandpass filter, an amplifier, a sampling and holding circuit, a comparator, etc., which are not shown.

[0162] Structure of the transmitting sensor unit and the receiving sensor unit

[0163] Next, the configurations of the transmission unit 50A and the reception unit 50B will be described.

[0164] Figure 4 This shows a state where the second unit 4 is opened relative to the first unit 3. When the second unit 4 is opened relative to the first unit 3, the inside of the first unit 3 and the inside of the second unit 4 are revealed.

[0165] A transmission-side path forming member 36 is provided at the inner side of the first unit 3 , and when the second unit 4 is opened relative to the first unit 3 , the transmission-side path forming member 36 is revealed.

[0166] Furthermore, a receiving-side path forming member 39 is provided at the inner side of the second unit 4 , and when the second unit 4 is opened relative to the first unit 3 , the receiving-side path forming member 39 is revealed.

[0167] The sending-side path forming member 36 and the receiving-side path forming member 39 form a part of the upstream feeding path R0 , the downstream feeding path R1 , and the reading conveying path R2 .

[0168] like Figure 5 As shown in FIG. 1 , a cover 37 is provided on the transmission side path forming member 36. The cover 37 is provided to enable the image Figure 5 , Figure 6 The state of being installed as shown, and Figure 7 The cover 37 is provided so as to be detachable from the transmission-side path forming member 36 in a state of being removed as shown. The cover 37 is provided so as to be attachable to the transmission-side path forming member 36 by an engaging structure (not shown).

[0169] The cover 37 has a circular opening 37a, and is configured so that the sensor center axis Lx of the ultrasonic detection unit 50 passes through the vicinity of the center of the opening 37a. A part of a first protective member 70 described later appears inside the opening 37a.

[0170] A transmitting unit 50A is provided on the inner side of the cover 37. When the cover 37 is removed, Figure 7 The transmission unit 50A is shown as shown. Figure 6When the cover 37 is installed as shown, a portion of the transmission unit 50A will be visible, but when the cover 37 is opened, the transmission unit 50A will appear larger. Figure 6 In the illustrated mounted state of the cover 37 , a portion of a first wall portion 60 b of a transmission substrate holder 60 described later is visible.

[0171] A roller holding member 38 for holding the separation roller 15 is provided inside the cover 37 . When the cover 37 is removed, the roller holding member 38 can be removed, and the separation roller 15 can be replaced together with the roller holding member 38 .

[0172] In addition, Figure 6 In the figure, reference numeral 15 a denotes a rotation axis of the separation roller 15 , and reference numeral 15 b denotes a torque limiter for applying a separation torque to the separation roller 15 .

[0173] In addition, Figure 5 In the figure, symbol Ba1 is the distance between the rotation axis center of the separation roller 15 and the rotation axis center of the second lower roller 17, that is, the axis distance, and symbol Ba2 is the distance between the rotation axis center of the second lower roller 17 and the rotation axis center of the third lower roller 21, that is, the axis distance.

[0174] In the present embodiment, the inter-axial distance Ba1 is shorter than the inter-axial distance Ba2. In other words, the path length of the downstream feeding path R1 is shorter than the path length of the reading transport path R2.

[0175] In addition, in the present embodiment, the inter-axial distance Ba1 is 29.1 mm, and the inter-axial distance Ba2 is 34.0 mm.

[0176] Next, if Figure 8 As shown, a conveying motor 47 and a main substrate 48 are provided at the -Da direction side of the transmission side path forming member 36. The conveying motor 47 is provided at the end of the -X direction on the back side of the transmission side path forming member 36.

[0177] The main substrate 48 constitutes the above-mentioned control unit 80. Fig. 9 As shown, a transmission unit 50A is provided between the main substrate 48 and the transmission-side path forming member 36 .

[0178] Although the structure of the transmission unit 50A will be described in detail later, the transmission unit 50A uses a transmission substrate holder 60 as a base, and the transmission substrate holder 60 is fixed to the transmission-side path forming member 36 by screws 61 , 61 .

[0179] Next, if Fig.10As shown, a circular opening 39a is formed in the receiving side path forming member 39, and the sensor center axis Lx of the ultrasonic detection unit 50 passes through the vicinity of the center of the opening 39a. A part of the second protective member 73 described later appears inside the opening 39a.

[0180] In addition, Fig.10 In the figure, symbol Bb1 is the distance between the rotation axis center of the feed roller 14 and the rotation axis center of the second upper roller 18, that is, the axis distance, and symbol Bb2 is the distance between the rotation axis center of the second upper roller 18 and the rotation axis center of the third upper roller 22, that is, the axis distance.

[0181] In the present embodiment, the interaxial distance Bb1 is shorter than the interaxial distance Bb2. In other words, the path length of the downstream feeding path R1 is shorter than the path length of the reading transport path R2.

[0182] In addition, in the present embodiment, the center distance Bb1 is 30.0 mm, and the center distance Bb2 is 34.0 mm.

[0183] like Fig.11 As shown, at the +Da direction side of the receiving-side path forming member 39 , a receiving unit 50B is provided.

[0184] Although the structure of the receiving unit 50B will be described in detail later, the receiving unit 50B uses the receiving substrate holder 62 as a base, and fixes the fixed portion 62j, which is a part constituting the receiving substrate holder 62, to the receiving side path forming member 39 by the receiving side holder fixing screw 63. In addition, reference numeral 39b is a positioning portion provided on the receiving side path forming member 39, and the positioned portion 62k of the receiving substrate holder 62 is positioned relative to the receiving side path forming member 39 by fitting a hole portion 62e exposed on the positioned portion 62k of the receiving substrate holder 62 with the positioning portion 39b.

[0185] In the above manner, the receiving substrate holder 62 is positioned and fixed relative to the receiving-side path forming member 39 .

[0186] Next, refer to Fig.12 The structures of the transmission unit 50A and the reception unit 50B are further described in the following drawings.

[0187] like Fig.12As shown, the ultrasonic detection unit 50 is arranged in the space between the first roller pair 13 and the second roller pair 16. Along the conveying direction Fp, the separation roller 15 constituting the first roller pair 13, the transmission unit 50A, the second lower roller 17 constituting the second roller pair 16, and the third lower roller 21 constituting the third roller pair 20 are arranged in this order. In addition, along the conveying direction Fp, the feed roller 14 constituting the first roller pair 13, the reception unit 50B, the second upper roller 18 constituting the second roller pair 16, and the third upper roller 22 constituting the third roller pair 20 are arranged in this order.

[0188] like Fig.13 , Fig.14 As shown, the transmission unit 50A is configured such that a transmission substrate 52 and a first protective member 70 are provided on a transmission substrate holder 60 .

[0189] Similarly, the receiving unit 50B is configured such that the receiving substrate 55 and the second protective member 73 are provided on a receiving substrate holder 62 .

[0190] Sending substrate holder 60 also like Fig.17 , Fig.18 As shown in FIG. 1 , the screw fixing portions 60j and 60k are provided with screw holes 60e, respectively, and a reference Fig. 9 The screw 61 described above. A fixing portion 60a is formed between the screw fixing portion 60j and the screw fixing portion 60k so as to be located in the +Da direction compared to the screw fixing portions 60j and 60k. The fixing portion 60a is a portion for fixing the first protective member 70, and a first opening 60f is formed at the center of the fixing portion 60a (see Fig.17 , Fig.18 , Fig. 22 ), and the first opening 60f is formed in such a way that the sensor center axis Lx of the ultrasonic detection unit 50 passes through the vicinity of the center of the first opening 60f.

[0191] Protection member positioning portions 60c, 60c are formed on the surface of the fixing portion 60a. Fig.19 As shown, the first protection member 70 is held by the first holding member 71, and recesses 71a, 71a are formed on the first holding member 71. The first holding member 71, i.e., the first protection member 70 is positioned relative to the fixing portion 60a by fitting the recesses 71a, 71a with the protection member positioning portions 60c, 60c.

[0192] like Fig.18 As shown in FIG. 1 , a cylindrical protrusion 60m is formed on the inner side of the fixing portion 60a, and a screw hole 60g is formed on the protrusion 60m. Fig.14As shown, a substrate positioning portion 60d is formed at the inner side of the fixing portion 60a.

[0193] like Fig.15 As shown, an opening 52a and a recess 52b are formed on the transmission substrate 52. The opening 52a is engaged with the protrusion 60m of the transmission substrate holder 60, and the recess 52b is engaged with the substrate positioning portion 60d of the transmission substrate holder 60, thereby positioning the transmission substrate 52 relative to the transmission substrate holder 60. Fig.14 As shown, the transmission substrate fixing screw 54 and the screw hole 60g ( Fig.18 ) are engaged, thereby fixing the sending substrate 52 relative to the sending substrate bracket 60.

[0194] The transmission substrate holder 60 is arranged so that the transmission surface 53a of the transmission sensor chip 53 is opposite to the original surface S. Fig. 22 The transmitting substrate 52 is held so as to be inclined at the angle α1 as shown. Thus, the transmitting surface 53a of the transmitting sensor chip 53 and the receiving surface 56a of the receiving sensor chip 56 are parallel, and the sensor central axis Lx is inclined at the angle β relative to the document surface S.

[0195] In addition, if Fig.13 , Fig.14 , Fig.17 , Fig.18 As shown, a first wall portion 60b is formed upstream of the fixed portion 60a in the conveying direction Fp, and a second wall portion 60h is formed downstream of the fixed portion 60a in the conveying direction Fp.

[0196] The first wall portion 60b is located in the image Figure 6 As shown, the cover 37 is in a position visible from the outside in a closed state, thereby playing a function of protecting the transmission substrate 52 from foreign matter, liquid, etc.

[0197] Although not shown in the figure, when the first wall portion 60b is viewed from the upstream of the conveying direction Fp, the first wall portion 60b is located at a position overlapping with a part of the transmission substrate 52 and the entire transmission sensor chip 53. In other words, when the first wall portion 60b is viewed from the upstream of the conveying direction Fp, a part of the transmission substrate 52 and the entire transmission sensor chip 53 are located at a position covered by the first wall portion 60b.

[0198] Next, the receiving substrate holder 62 has a reference Fig.11The fixed portion 62j and the positioned portion 62k are described, and a fixing portion 62a is formed between the fixed portion 62j and the positioned portion 62k so as to be located in the -Da direction from the fixed portion 62j and the positioned portion 62k. The fixing portion 62a is a portion for fixing the second protective member 73, and a second opening 62f is formed at the center of the fixing portion 62a (see Fig. 22 ), and the second opening 62f is formed in such a way that the sensor center axis Lx of the ultrasonic detection unit 50 passes through the vicinity of the center of the second opening 62f.

[0199] like Fig.14 As shown in FIG. 1 , protective member positioning portions 62c, 62c are formed on the surface of the fixing portion 62a. The second protective member 73 is held by the second holding member 74, and recessed portions 74a, 74a are formed on the second holding member 74. By fitting the recessed portions 74a, 74a with the protective member positioning portions 62c, 62c, the second holding member 74, i.e., the second protective member 73, is positioned relative to the fixing portion 62a.

[0200] like Fig.13 As shown, a protruding substrate positioning portion 62d is formed on the inner side of the fixing portion 62a. A recess 55b is formed on the receiving substrate 55. The recess 55b is engaged with the substrate positioning portion 62d. In addition, although not shown in the figure, a protrusion and a screw hole similar to the protrusion 60m and the screw hole 60g of the sending substrate holder 60 are formed on the receiving substrate holder 62. In addition, a protrusion and a screw hole similar to the opening 52a of the sending substrate 52 are formed on the receiving substrate 55 (see Fig.15 ) is the same opening. And, by fitting the opening with the protrusion of the receiving substrate holder 62, and fitting the recess 55b of the receiving substrate 55 with the substrate positioning portion 62d of the receiving substrate holder 62, the receiving substrate 55 is positioned relative to the receiving substrate holder 62. And, as Fig.13 As shown, the receiving substrate 55 is fixed to the receiving substrate holder 62 by fitting the receiving substrate fixing screws 57 into the screw holes.

[0201] The receiving substrate holder 62 is arranged so that the receiving surface 56a of the receiving sensor chip 56 is opposite to the original surface S. Fig. 22 The receiving substrate 55 is held so as to be inclined at the angle α1 as shown. Thus, the receiving surface 56a of the receiving sensor chip 56 and the transmitting surface 53a of the transmitting sensor chip 53 are parallel, and the sensor central axis Lx is inclined at the angle β relative to the document surface S.

[0202] As described above, in this embodiment, the transmission substrate 52 is fixed to the transmission side path forming member 36 as a member forming the document conveying path via the transmission substrate holder 60, and the reception substrate 55 is fixed to the reception side path forming member 39 as a member forming the document conveying path via the reception substrate holder 62. As a result, the distance between the document P and the transmission sensor chip 53 and the distance between the document P and the reception sensor chip 56 are relatively stable, and the ultrasonic detection value is relatively stable.

[0203] Next, the structure of the transmission substrate 52 will be described.

[0204] like Figures 13 to 15 As shown, the transmission substrate 52 is a rectangular substrate having short sides E1 and long sides E2, and a recess 52b is formed on one of the short sides E1 as described above. The transmission substrate 52 is disposed so that the short side E1 is along the conveying direction Fp.

[0205] The transmission sensor chip 53 is fixed in a state of being mounted on the substrate surface 52 d of the transmission substrate 52 , and there is no member such as a pedestal between the transmission sensor chip 53 and the substrate surface 52 d except for an adhesive.

[0206] A connector 52c is provided on the opposite side of the transmission substrate 52 from the substrate surface 52d, and a transmission-side cable 76 (see FIG. 5 ) is connected to the connector 52c. Fig.13 , Fig.14 ).

[0207] Furthermore, a first surrounding member 65 is provided on the substrate surface 52d of the transmission substrate 52. In the present embodiment, the first surrounding member 65 is formed of a metal plate material and is fixed to the transmission substrate 52 by an adhesive.

[0208] The first surrounding member 65 has an opening 65a formed therein so that the sensor center axis Lx of the ultrasonic detection unit 50 passes through the vicinity of the center of the opening 65a. Fig.16 As shown, it is arranged along the substrate surface 52d.

[0209] The transmission substrate fixing screw 54 includes a head having a screwdriver fitting hole, a threaded portion having an external thread, and a top end portion of the external threaded head. The threaded portion is mounted on the mounting portion, specifically, the screw hole 60g (see FIG. 1 ) on the same side as the transmission sensor chip 53 with respect to the substrate surface 52d of the transmission substrate 52. Fig.18 , Fig. 22 ). In addition, the threaded portion may be mounted on a mounted portion, ie, a screw hole, on the opposite side of the transmitting sensor chip 53 with respect to the substrate surface 52d of the transmitting substrate 52.

[0210] When the transmission substrate 52 is fixed to the transmission substrate holder 60 , the tip 54 a of the transmission substrate fixing screw 54 is located closer to the −Da direction than the most +Da direction position 65 b of the first surrounding member 65 in the normal direction Da.

[0211] In addition, the direction along the sensor center axis Lx and from the transmitting unit 50A toward the receiving unit 50B is set as the +Lx direction, and the opposite direction is set as the -Lx direction. When the transmitting substrate 52 is fixed relative to the transmitting substrate bracket 60, the position of the top end portion 54a of the transmitting substrate fixing screw 54 is located closer to the +Lx direction than the first surrounding part 65.

[0212] Furthermore, the distance from the substrate surface 52 d of the transmission substrate 52 to the first surrounding member 65 is shorter than the length of the threaded portion of the transmission substrate fixing screw 54 .

[0213] exist Fig.16 In FIG. 5 , symbol t0 is the thickness including the transmission substrate 52 and the transmission sensor chip 53 , symbol t1 is the thickness of the transmission substrate 52 , and symbol t2 is the thickness of the transmission sensor chip 53 . The thickness t2 of the transmission sensor chip 53 is thinner than the thickness of the transmission substrate 52 .

[0214] As an example, the thickness of the transmission substrate 52 can be set to 0.8 to 1.2 mm, and can be set to 1.0 mm in particular. In addition, as an example, the thickness of the transmission sensor chip 53 can be set to 0.5 to 0.7 mm, and can be set to 0.578 mm in particular.

[0215] As an example, the distance from the substrate surface 52 d of the transmission substrate 52 to the first surrounding member 65 can be set to 1.2 to 1.6 mm, and can be set to 1.4 mm in particular.

[0216] In addition, by Fig.13 and Fig.14 It is clear that the receiving substrate 55 has the same structure as the transmitting substrate 52 , and the shape and size of the receiving substrate 55 are also the same as those of the transmitting substrate 52 .

[0217] That is, the receiving substrate 55 is a rectangular substrate having a short side E1 and a long side E2 , and is provided so that the short side E1 is along the conveying direction Fp.

[0218] The receiving substrate 55 is provided with a connector 55 c , and a receiving-side cable 77 is connected to the connector 55 c .

[0219] In addition, a second surrounding member 67 (see Fig. 22 ). The second surrounding member 67 is formed of a metal plate and is fixed to the receiving substrate 55 by an adhesive.

[0220] The second surrounding member 67 has an opening similar to the opening 65a of the first surrounding member 65, and the opening is formed so that the sensor central axis Lx of the ultrasonic detection unit 50 passes near the center of the opening. The second surrounding member 67 is provided along the substrate surface 55d.

[0221] In addition, the thicknesses of the receiving substrate 55 and the receiving sensor chip 56 are also the same as the thicknesses of the transmitting substrate 52 and the transmitting sensor chip 53 described above, respectively.

[0222] The receiving substrate fixing screw 57 includes a head having a screwdriver fitting hole, a threaded portion having an external thread, and a top end portion of the external threaded head. The threaded portion is mounted on the mounting portion, specifically, the screw hole 62g (see FIG. 6 ) on the same side as the receiving sensor chip 56 relative to the substrate surface 55d of the receiving substrate 55. Fig. 22 ). In addition, the threaded portion may be mounted on a mounted portion, ie, a screw hole, on the opposite side of the receiving sensor chip 56 with respect to the substrate surface 55d of the receiving substrate 55.

[0223] When the receiving substrate 55 is fixed to the receiving substrate holder 62, the tip 57a of the receiving substrate fixing screw 57 is located closer to the +Da direction than the position 67b of the second surrounding member 67 in the -Da direction in the normal direction Da.

[0224] When the receiving substrate 55 is fixed to the receiving substrate holder 62 , the tip 57 a of the receiving substrate fixing screw 57 is located closer to the second surrounding member 67 in the −Lx direction in the axial direction of the sensor central axis Lx.

[0225] Furthermore, the distance from the substrate surface 55 d of the receiving substrate 55 to the second surrounding member 67 is shorter than the length of the threaded portion of the receiving substrate fixing screw 57 .

[0226] As an example, the distance from the substrate surface 55 d of the receiving substrate 55 to the second surrounding member 67 can be set to 1.2 to 1.6 mm, and can be set to 1.4 mm in particular.

[0227] As described above, since a first enclosing component is provided on the sending substrate 52, the first enclosing component is a component that encloses the sending sensor chip 53, and is a plate-shaped component provided along the sending substrate 52, and a second enclosing component is provided on the receiving substrate 55, the second enclosing component is a component that encloses the receiving sensor chip 56, and is a plate-shaped component provided along the receiving substrate 55, the sending sensor chip 53 or the receiving sensor chip 56 can be protected from external forces.

[0228] Structure of the first protection member and the second protection member

[0229] Next, the first protection member 70 and the second protection member 73 will be described in detail.

[0230] In addition, in this embodiment, since the first protective component 70 and the second protective component 73 are made of the same material, the second retaining component 74 that retains the second protective component 73 is also made of the same material as the first retaining component 71 that retains the first protective component 70. Therefore, in the following, the first protective component 70 and the first retaining component 71 are described, and the description of the second protective component 73 and the second retaining component 74 is omitted.

[0231] In the present embodiment, the first protective member 70 is a filter configured in a mesh shape. Fig. 20 This is a diagram showing an enlarged portion of the first protective member 70 .

[0232] exist Fig. 20 In the embodiment, the first protective member 70 is a filter formed into a mesh shape by cross-arranging wires 70a. Fig. 20 2 shows an example in which the wires 70a are crossed at 90°, but the present invention is not limited thereto, and the wires 70a may be crossed at an angle other than 90°.

[0233] As the material of the wire material 70a, metal materials or alloy materials such as copper, iron, brass, and SUS, synthetic resins such as nylon and polyester, etc. can be used. In this embodiment, polyester is used as an example.

[0234] In addition, the wire diameter of the wire 70a is preferably set to be smaller than the wavelength of the ultrasonic wave. This can suppress the problem of diffuse reflection of the ultrasonic wave by the wire 70a of the first protective member 70.

[0235] In such a first protective member 70, an opening 70b is formed between a pair of adjacent wires 70a. The opening 70b corresponds to a hole portion through which ultrasonic waves pass. In order to suppress the attachment and accumulation of foreign matter such as paper dust to the transmitting surface 53a of the transmitting sensor chip 53 or the receiving surface 56a of the receiving sensor chip 56, it is preferred that the width of the opening 70b, that is, the opening width Wa, is set to 1 mm or less.

[0236] However, in the present embodiment, when the device is cleaned with a cleaning agent, in order to prevent the cleaning agent from passing through the opening 70 b , the opening width Wa is set to 30 μm or less, and is set to 22 μm as an example.

[0237] In addition, although Figures 12 to 14 , Fig.19 In order to easily understand that the first protective component 70 or the second protective component 73 is a grid-like component, the first protective component 70 or the second protective component 73 is represented as a grid-like component, but the crossing angle and opening width Wa of the wire 70a are just the crossing angle and opening width represented for the sake of ease of understanding.

[0238] As described above, since the first protective member 70 and the second protective member 73 are mesh-shaped members, ultrasonic waves can be well passed through the first protective member 70 and the second protective member 73 .

[0239] Since the opening width Wa of the grid-shaped member is 30 μm or less, it is possible to suppress the cleaning agent from passing through the first protective member 70 and adhering to the transmitting sensor chip 53 or the cleaning agent from passing through the second protective member 73 and adhering to the receiving sensor chip 56 when the device is cleaned with the cleaning agent. As a result, it is possible to suppress the inconvenience of the intensity of the ultrasonic wave received by the receiving sensor chip 56 being reduced, thereby causing erroneous detection.

[0240] like Fig.19 As shown, the first protective member 70 is held by a first holding member 71 having an opening 71b for exposing the first protective member 70. The first protective member 70 is held by the first holding member 71 by being sandwiched between two first holding members 71. A double-sided tape (not shown) is used between the first protective member 70 and the first holding member 71, thereby integrating the first protective member 70 and the first holding member 71.

[0241] In addition, the relationship between the second protection member 73 and the second holding member 74 is also the same as the relationship between the first protection member 70 and the first holding member 71 described above.

[0242] Next, the first protective member 70 is moved by the substrate holder 60 so as to be aligned with the original surface S. Fig. 22 Similarly, the second protective member 73 is held in a manner inclined at an angle α2 relative to the manuscript surface S by receiving the substrate holder 62. As a result, the angle between the first protective member 70 and the second protective member 73 becomes 0°, that is, the first protective member 70 and the second protective member 73 become parallel.

[0243] In the present embodiment, the angle α2 is set to be different from the angle α1. Specifically, the angle α2 is set to be smaller than the angle α1.

[0244] That is, if the angle α2 and the angle α1 are set to the same angle, that is, the transmitting surface 53a and the first protective member 70 are parallel, multiple reflections of the ultrasonic wave will be caused between the transmitting surface 53a and the first protective member 70, and there is a possibility that accurate double transmission detection cannot be performed. The same situation also occurs when the receiving surface 56a and the second protective member 73 are parallel.

[0245] However, since the angle α2 is set to be different from the angle α1 as described above, the above-mentioned multiple reflections can be suppressed and the double-feed detection can be appropriately performed.

[0246] In addition, in the present embodiment, as an example, the angle α1 is set to 20° and the angle α2 is set to 15°.

[0247] In addition, the distance between the transmission surface 53a and the first protective member 70 also becomes a major factor causing multiple reflections of ultrasonic waves. That is, if the distance between the transmission surface 53a and the first protective member 70 is short, multiple reflections of ultrasonic waves will be caused. In this embodiment, based on this viewpoint, the distance between the transmission surface 53a and the first protective member 70, that is, the distance along the sensor center axis Lx is set to 4.0 mm to 6.0 mm, and is set to 4.89 mm as an example.

[0248] Since the first protective member 70 and the transmission substrate 52 are held together by the transmission substrate holder 60 as described above, it is possible to suppress the variation in the distance between the transmission sensor chip 53 and the first protective member 70. As a result, it is possible to appropriately suppress the multiple reflections of the ultrasonic wave between the transmission sensor chip 53 and the first protective member 70.

[0249] Similarly, since the second protective member 73 and the receiving substrate 55 are held together by the receiving substrate holder 62, it is possible to suppress the variation in the distance between the receiving sensor chip 56 and the second protective member 73. As a result, multiple reflections of ultrasonic waves between the receiving sensor chip 56 and the second protective member 73 can be appropriately suppressed.

[0250] Furthermore, the transmission substrate holder 60 has a first opening 60 f through which ultrasonic waves pass on the sensor central axis Lx, and the first protection member 70 is provided on the surface of the transmission substrate holder 60 so as to cover the first opening 60 f.

[0251] Similarly, the receiving substrate holder 62 has a second opening 62 f through which ultrasonic waves pass on the sensor central axis Lx, and the second protective member 73 is provided on the surface of the receiving substrate holder 62 so as to cover the second opening 62 f.

[0252] Thereby, the following effects can be obtained.

[0253] If foreign matter remains attached to the first protective member 70 or the second protective member 73, the intensity of the ultrasonic wave received by the receiving sensor chip 56 may decrease, resulting in a possibility of erroneous detection. Therefore, in this case, the first protective member 70 or the second protective member 73 needs to be replaced or cleaned.

[0254] In the present embodiment, since the first protective member 70 is provided on the surface of the transmission substrate holder 60 so as to cover the first opening 60 f , replacement and maintenance of the first protective member 70 are easy.

[0255] In addition, similarly, since the second protective member 73 is provided on the surface of the receiving substrate holder 62 so as to cover the second opening 62 f , replacement and maintenance of the second protective member 73 are easy.

[0256] In addition, as referenced Fig. 22 As described above, the transmission sensor chip 53 and the reception sensor chip 56 are inclined at the angle α1 which is the first angle with respect to the surface of the document P passing between the transmission sensor chip 53 and the reception sensor chip 56 .

[0257] Furthermore, the first protective member 70 and the second protective member 73 are inclined at an angle α2 as a second angle with respect to the surface of the document P passing between the transmission sensor chip 53 and the reception sensor chip 56 .

[0258] Furthermore, the angle α1 is different from the angle α2, and the angle α2 is gentler than the angle α1.

[0259] Thereby, the following effects can be obtained.

[0260] When the first protective component 70 and the second protective component 73 are parallel to the surface of the original document P passing between the sending sensor chip 53 and the receiving sensor chip 56, paper dust and the like are easily attached to the first protective component 70 and the second protective component 73. However, since the first protective component 70 and the second protective component 73 are inclined at an angle α2 relative to the surface of the original document P passing between the sending sensor chip 53 and the receiving sensor chip 56, the attachment of foreign matter such as paper dust to the first protective component 70 and the second protective component 73 can be suppressed.

[0261] In addition, since the transmitting sensor chip 53 and the receiving sensor chip 56 are inclined at an angle α1 relative to the surface of the original document P passing between the transmitting sensor chip 53 and the receiving sensor chip 56, multiple reflections of ultrasonic waves between the transmitting sensor chip 53 and the original document P or between the receiving sensor chip 56 and the original document P can be suppressed.

[0262] Furthermore, since the angle α1 and the angle α2 are different, multiple reflections of ultrasonic waves between the transmitting sensor chip 53 and the first protective member 70 can be suppressed, and multiple reflections of ultrasonic waves between the receiving sensor chip 56 and the second protective member 73 can be suppressed.

[0263] In addition, as referenced Figures 5 to 7 As described above, the scanner 1 includes the transmission side path forming member 36, which is a member that forms the reading conveying path R2 as the document conveying path between the first roller pair 13 and the second roller pair 16, and fixes the transmission substrate holder 60. The transmission side path forming member 36 is provided with a detachable cover 37, and when the cover 37 is mounted, the transmission substrate holder 60 is covered by the cover 37, and when the cover 37 is removed, the separation roller 15 can be replaced, and the transmission substrate holder 60 is exposed. In particular, the first protective member 70 is exposed.

[0264] This makes it possible to easily access the transmission substrate holder 60. As a result, for example, replacement and maintenance of the first protective member 70 are facilitated.

[0265] In addition, the transmission substrate holder 60 has a fixing portion 60a, the fixing portion 60a fixes the first protection member 70, the transmission substrate 52 is fixed to the inner side of the fixing portion 60a, and the fixing portion 60a has a first wall portion 60b, which is a wall portion opposite to the side of the fixed transmission substrate 52 and covers at least a part of the transmission substrate 52. Therefore, when a foreign object tries to bypass the side of the fixing portion 60a to the transmission substrate 52, the foreign object can be blocked by the first wall portion 60b.

[0266] Relationship between the structure of the ultrasonic detection unit and other structures of the scanner

[0267] Next, the relative positional relationship between the configuration of the ultrasonic detection unit 50 and other configurations of the scanner 1 will be described.

[0268] First, refer to Fig.23 Next, the positional relationship between the ultrasonic detection unit 50 and the first roller pair 13 will be described. Fig.23 FIG. 2 shows the positional relationship between the ultrasonic detection unit 50 and the first roller pair 13 as viewed from the upstream in the conveying direction Fp. Fig.23 In FIG. 1 , the feed roller 14 and the separation roller 15 constituting the first roller pair 13 are indicated by two-dot chain lines.

[0269] As shown in the figure, at least a portion of the transmitting sensor chip 53 and at least a portion of the receiving sensor chip 56 are located inside the range Ua1 of the first roller pair 13 in the normal direction Da to the document surface S at the clamping position of the first roller pair 13. This can reduce the size of the device in the normal direction Da.

[0270] In addition, although in the present embodiment, all of the transmitting sensor chip 53 and all of the receiving sensor chip 56 are located inside the range Ua1 in the normal direction Da, a part of the transmitting sensor chip 53 and a part of the receiving sensor chip 56 may be located inside the range Ua1 in the normal direction Da. Alternatively, a part of the transmitting sensor chip 53 and all of the receiving sensor chip 56 may be located inside the range Ua1 in the normal direction Da. Alternatively, all of the transmitting sensor chip 53 and a part of the receiving sensor chip 56 may be located inside the range Ua1 in the normal direction Da.

[0271] In addition, reference numeral 14a denotes the rotation axis of the feed roller 14, and reference numeral 15a denotes the rotation axis of the separation roller 15. In the present embodiment, the distance between the axis centers of the rotation axis 14a and the rotation axis 15a, i.e., the interaxial distance dk1, is 16.6 mm, which is shorter than the distance between the transmitting sensor chip 53 and the receiving sensor chip 56, i.e., the sensor distance of 24.9 mm. Thus, the occupied area of ​​the first roller pair 13 in the direction along the interaxial distance dk1 can be reduced, and the size of the device can be suppressed.

[0272] In the present embodiment, the shaft diameter of the rotating shaft 14 a is 6.0 mm, and the shaft diameter of the rotating shaft 15 a is 3.0 to 6.0 mm, and as an example, 3.9 mm or 5.18 mm, both of which are larger than the thickness of the transmitting sensor chip 53 or the receiving sensor chip 56 , which is 0.578 mm.

[0273] Next, refer to Fig.24 The positional relationship between the ultrasonic detection unit 50 , the second roller pair 16 , and the third roller pair 20 will be described. Fig.24 The positional relationship among the ultrasonic detection unit 50 , the second roller pair 16 , and the third roller pair 20 as viewed from the upstream in the conveyance direction Fp is shown.

[0274] exist Fig.24 In the figure, the second lower roller 17 and the second upper roller 18 constituting the second roller pair 16 are indicated by double dotted lines. In addition, the contour of the third lower roller 21 constituting the third roller pair 20 overlaps with the second lower roller 17, and the contour of the third upper roller 22 constituting the third roller pair 20 overlaps with the second upper roller 18.

[0275] Although the details will be described later, the second upper roller 18 and the third upper roller 22 are provided so as to move forward and backward together with respect to the opposing rollers. Fig.24 The second upper roller 18 and the third upper roller 22 are shown in a state where they are in contact with the opposing roller.

[0276] As shown in the figure, at least a part of the transmitting sensor chip 53 and at least a part of the receiving sensor chip 56 are located inside the range Ua2 of the second roller pair 16 or the third roller pair 20 in the normal direction Da of the document surface S at the clamping position of the second roller pair 16 or the third roller pair 20. As a result, the size of the device in the normal direction Da of the document surface S at the clamping position of the second roller pair 16 or the third roller pair 20 can be suppressed.

[0277] In addition, although the entire transmitting sensor chip 53 and the entire receiving sensor chip 56 are located inside the range Ua2 in the normal direction Da in the present embodiment, a part of the transmitting sensor chip 53 and a part of the receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da. Alternatively, a part of the transmitting sensor chip 53 and the entire receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da. Alternatively, the entire transmitting sensor chip 53 and a part of the receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da.

[0278] The relationship between the dimensions of the rotation axes of the second lower roller 17 , the second upper roller 18 , the third lower roller 21 , and the third upper roller 22 and the dimensions of the transmitting sensor chip 53 and the receiving sensor chip 56 will be described again later.

[0279] In addition, in the present embodiment, a part of the transmitting substrate 52 and the entire receiving substrate 55 are located inside the range Ua1 in the normal direction Da. However, the entire transmitting substrate 52 and the entire receiving substrate 55 may be located inside the range Ua1 in the normal direction Da. Alternatively, a part of the transmitting substrate 52 and a part of the receiving substrate 55 may be located inside the range Ua1 in the normal direction Da. Alternatively, the entire transmitting substrate 52 and a part of the receiving substrate 55 may be located inside the range Ua1 in the normal direction Da.

[0280] In addition, the distance between the rotation axis center of the second lower roller 17 and the rotation axis center of the second upper roller 18, or the distance between the rotation axis center of the third lower roller 21 and the rotation axis center of the third upper roller 22, that is, the axis spacing dk2 is 15.4 mm, and this distance is shorter than the distance between the sending sensor chip 53 and the receiving sensor chip 56, that is, the sensor spacing of 24.9 mm.

[0281] As a result, the occupied area of ​​the second roller pair 16 or the third roller pair 20 in the direction along the axis distance dk2 can be reduced, and the size of the device can be suppressed.

[0282] Next, the sending substrate 52 and the receiving substrate 55 are inclined relative to the following direction, which is the normal direction Da relative to the original surface S passing between the sending sensor chip 53 and the receiving sensor chip 56, and the sending surface 53a of the sending sensor chip 53 is along the surface of the sending substrate 52, and the receiving surface 56a of the receiving sensor chip 56 is along the surface of the receiving substrate 55.

[0283] Furthermore, at least a portion of the transmitting substrate 52 and at least a portion of the receiving substrate 55 are located within the range of the second roller pair 16 or the third roller pair 20 in the normal direction Da of the document surface S at the clamping position of the second roller pair 16 or the third roller pair 20. Thus, the size of the device in the normal direction Da can be suppressed.

[0284] In addition, although the entire transmitting substrate 52 and a part of the receiving substrate 55 are located inside the range Ua2 in the normal direction Da in the present embodiment, a part of the transmitting substrate 52 and a part of the receiving substrate 55 may be located inside the range Ua2 in the normal direction Da. Alternatively, a part of the transmitting substrate 52 and the entire receiving substrate 55 may be located inside the range Ua2 in the normal direction Da. Alternatively, the entire transmitting substrate 52 and the entire receiving substrate 55 may be located inside the range Ua2 in the normal direction Da.

[0285] In addition, in the present embodiment, the entirety of the transmitting sensor chip 53 and the entirety of the receiving sensor chip 56 are located inside the range Ua2 in the normal direction Da. However, a portion of the transmitting sensor chip 53 and a portion of the receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da. Alternatively, a portion of the transmitting sensor chip 53 and the entirety of the receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da. Alternatively, the entirety of the transmitting sensor chip 53 and a portion of the receiving sensor chip 56 may be located inside the range Ua2 in the normal direction Da.

[0286] Next, refer to Fig.25 The structure of the second roller pair 16 will be further described.

[0287] In the present embodiment, two sets of second roller pairs 16 are provided along the X-axis direction, that is, the document width direction, and the two sets of second roller pairs 16 are provided at symmetrical positions across the center position CL of the document P in the document width direction.

[0288] Indicated at 17 a is a rotation axis of the second lower roller 17 .

[0289] Reference numeral 18a1 denotes a rotation shaft located between the two second upper rollers 18 , and reference numeral 18a2 denotes rotation shafts located on both sides of the two second upper rollers 18 . The shaft diameter of the rotation shaft 18a1 is smaller than that of the rotation shaft 18a2 .

[0290] The rotation shaft 18a2 located in the +X direction is connected to the first universal joint 31A. A second universal joint 31B is provided in the +X direction relative to the first universal joint 31A, and the first universal joint 31A and the second universal joint 31B are connected via the rotation shaft 18a3.

[0291] Since the second upper roller 18 advances and retreats relative to the second lower roller 17 and transmits power, the second upper roller 18 can be driven while advancing and retreating relative to the second lower roller 17 through the first universal joint 31A and the second universal joint 31B.

[0292] exist Fig.25 The middle lower figure shows the state where the second upper roller 18 is connected to the second lower roller 17. Fig.25 The figure in the upper middle part shows a state where the second upper roller 18 is separated to the maximum extent from the second lower roller 17. Symbol M1 indicates the range in which the second upper roller 18 moves.

[0293] As shown in the figure, in this embodiment, since the entire receiving sensor chip 56 and the entire receiving substrate 55 are located inside the range M1 in the normal direction Da, the device size in the normal direction Da can be suppressed.

[0294] In addition, although the entire receiving sensor chip 56 and the entire receiving substrate 55 are located inside the range M1 in the normal direction Da in the present embodiment, a part of the receiving sensor chip 56 and a part of the receiving substrate 55 may be located inside the range M1 in the normal direction Da. Alternatively, the entire receiving sensor chip 56 and a part of the receiving substrate 55 may be located inside the range M1 in the normal direction Da.

[0295] The relationship between the third roller pair 20 , the receiving sensor chip 56 , and the receiving substrate 55 is also the same as the relationship between the second roller pair 16 , the receiving sensor chip 56 , and the receiving substrate 55 described above.

[0296] In this embodiment, the shaft diameter of the rotating shaft 17a is 6.0 mm. The shaft diameters of the rotating shaft 18a1, 18a2, and 18a3 are 4.5 mm, and these are larger than the thickness of the transmitting sensor chip 53 or the receiving sensor chip 56.

[0297] In addition, as described above, the path length between the first roller pair 13 and the second roller pair 16, that is, the path length of the downstream feeding path R1, is shorter than the path length between the second roller pair 16 and the third roller pair 20, that is, the path length of the reading conveying path R2. As a result, the path length between the first roller pair 13 and the second roller pair 16 can be suppressed, and the size of the device can be suppressed.

[0298] In addition, in this embodiment, as shown in FIG. Figures 13 to 15 As described above, the transmitting substrate 52 and the receiving substrate 55 have long sides E2 and short sides E1 and are arranged such that the short sides E1 extend along the conveying direction Fp. This allows the first roller pair 13 and the second roller pair 16 to be close to each other in the conveying direction Fp, thereby contributing to miniaturization of the device.

[0299] Furthermore, the lengths of the short sides E1 of the transmission substrate 52 and the reception substrate 55 are shorter than the length of the glass plate 32 e in the conveyance direction Fp.

[0300] Here, refer to Fig.26 The structures of the first reading unit 32 and the second reading unit 33 will be described. The structures of the first reading unit 32 and the second reading unit 33 are basically the same, and the structure of the first reading unit 32 will be described below.

[0301] The first reading unit 32 includes a lower frame 32f and an upper frame 32g, and has a sensor substrate 32a on the lower frame 32f. A linear image sensor 32b is provided on the sensor substrate 32a as an example of a reading sensor, and the image sensor 32b receives reflected light arriving from the original P via the lens 32c. In addition, reference numeral 32d is a light source for irradiating the original P.

[0302] A glass plate 32e is provided on the upper housing 32g. The glass plate 32e not only allows light reflected by the document P to pass through the lens 32c, but also has a function of contacting the document P and guiding the document P downstream.

[0303] Moreover, as described above, the length of the short side E1 of the transmitting substrate 52 and the receiving substrate 55 is shorter than the length of the glass plate 32e in the conveying direction Fp. In addition, in the present embodiment, the length of the short side E1 of the transmitting substrate 52 and the receiving substrate 55 is 8.6 mm, the length of the long side E2 is 26.8 mm, and the length of the glass plate 32e in the conveying direction Fp is 12.6 mm.

[0304] As described above, the length of the short side E1 of the transmission substrate 52 and the reception substrate 55 in the conveyance direction Fp can be reduced. As a result, the first roller pair 13 and the second roller pair 16 can be brought closer in the conveyance direction Fp, which can further contribute to the miniaturization of the device.

[0305] In addition, in the present embodiment, the thickness of the glass plate 32 e is 1.1 mm, which is larger than the thickness of the transmission sensor chip 53 or the reception sensor chip 56 , which is 0.578 mm.

[0306] Next, Fig. 27 FIG. 2 shows the positional relationship between the transmission substrate 52 and the transmission sensor chip 53, the sensor substrate 32a, and the image sensor 32b when the transmission substrate 52 and the transmission sensor chip 53 are viewed from upstream in the conveying direction Fp. Fig. 27 In FIG. 1 , the sensor substrate 32 a and the image sensor 32 b are indicated by two-dot chain lines.

[0307] As shown in the figure, the transmitting sensor chip 53 is located on the +Da side, that is, on the second reading unit 33 side, compared with the image sensor 32b in the normal direction Da. As a result, the amount of the transmitting sensor chip 53 protruding from the first reading unit 32 to the -Da side, that is, the lower side in the normal direction Da can be suppressed, and the device size in the normal direction Da can be suppressed.

[0308] Next, Fig.28 FIG. 2 shows the positional relationship between the transmission substrate 52 and the transmission sensor chip 53 and the second reading unit 33 when the transmission substrate 52 and the transmission sensor chip 53 are viewed from upstream in the conveying direction Fp. Fig.28 In FIG. 1 , the outer shape of the second reading section 33 and the image sensor 32 b included in the second reading section 33 are indicated by a two-dot chain line.

[0309] The second reading section 33 moves forward and backward relative to the first reading section 32. Fig.28 The figure below shows the state in which the first reading unit 32 is separated to the greatest extent. Fig.28 The figure above shows the state where the second reading section 33 has entered the first reading section 32 to the greatest extent. The range indicated by symbol M2 indicates the area where the second reading section 33 is displaced.

[0310] As shown in the figure, at least a part of the receiving sensor chip 56 is located inside the range M2 in the normal direction Da. Thus, the device size in the normal direction Da can be suppressed.

[0311] Likewise, at least a portion of the receiving substrate 55 is located inside the range M2 in the normal direction Da. This makes it possible to suppress the size of the device in the normal direction Da.

[0312] In addition, although the entire receiving sensor chip 56 and the entire receiving substrate 55 are located inside the range M2 in the normal direction Da in the present embodiment, a portion of the receiving sensor chip 56 and a portion of the receiving substrate 55 may be located inside the range M2 in the normal direction Da. Alternatively, the entire receiving sensor chip 56 and a portion of the receiving substrate 55 may be located inside the range M2 in the normal direction Da.

[0313] Next, Fig.29 The occupied areas of the first roller pair 13 , the second roller pair 16 , the conveying motor 47 , the transmission sensor chip 53 , the transmission substrate 52 , the reception sensor chip 56 , and the reception substrate 55 are shown when viewed from the X-axis direction.

[0314] As shown in the figure, at least a part of the transmission substrate 52 and at least a part of the transmission sensor chip 53 are located in the occupied area of ​​the conveying motor 47. This can suppress the increase in size of the device.

[0315] In addition, although in the present embodiment, a portion of the transmitting substrate 52 and the entire transmitting sensor chip 53 are located within the occupied area of ​​the conveying motor 47, the entire transmitting substrate 52 and the entire transmitting sensor chip 53 may be located within the occupied area of ​​the conveying motor 47, or a portion of the transmitting substrate 52 and a portion of the transmitting sensor chip 53 may be located within the occupied area of ​​the conveying motor 47.

[0316] The present invention is not limited to the embodiments described above, but various modifications can be made within the scope of the invention described in the claims, and it is obvious that such modifications are also included in the scope of the present invention.

[0317] For example, although the medium conveying device 100 is applied to the scanner 1 as an example of an image reading device in the above embodiment, it is not limited to this and can also be applied to a recording device that records on a medium, and a post-processing device that performs post-processing such as stapling or punching on a medium.

[0318] Explanation of symbols

[0319] 1… scanner; 2… device body; 3… first unit; 4… second unit; 4a… upper surface; 5… third unit; 6… main body support portion; 6a… vertical wall portion; 6b… elastic deformation portion; 6c… main body rotation axis; 6e… first contact portion; 6f… second contact portion; 7… operation portion; 7a, 7b, 7c… operation buttons; 7d… display portion; 8a… lock release portion; 9… document support member; 10… upper opening and closing portion; 11… document support portion; 13… first roller pair; 14… feed roller; 15… separation roller; 15a… rotation axis; 15b… torque limiter; 16… second roller pair; 17… second lower roller; 18… second upper roller; 20… third roller pair; 21… third lower roller; 21a… rotation axis; 22… third upper roller ; 22a…rotating shaft; 24…fourth roller pair; 25…fourth driving roller; 26…fourth driven roller; 28…fifth roller pair; 29…fifth driving roller; 30…fifth driven roller; 31A…first universal joint; 31B…second universal joint; 32…first reading section; 32a…sensor substrate; 32b…image sensor; 32c…lens; 32d…light source; 32e…glass plate; 32f…lower frame; 32g…upper frame; 33…second reading section; 34…pressing spring; 35…baffle; 36…transmitting side path forming member; 37…cover; 37a…opening; 38…roller holding member; 39…receiving side path forming member; 39a…opening; 39b…positioning section; 47…transmission motor; 48…main Substrate; 50…ultrasonic detection unit; 50A…transmitting unit; 50B…receiving unit; 52…transmitting substrate; 52a…opening; 52b…recess; 52c…connector; 52d…substrate surface; 53…transmitting sensor chip; 53a…transmitting surface; 54…screw for fixing the transmitting substrate; 55…receiving substrate; 55c…connector; 56…receiving sensor chip; 56a…receiving surface; 57…screw for fixing the receiving substrate; 58…transmitting circuit; 59…receiving circuit; 60…transmitting substrate bracket; 60a…fixing portion; 60b…first wall; 60c…protection component positioning portion; 60d…substrate positioning portion; 60e…screw hole; 60f…first opening; 60g…screw hole; 60h…second wall; 60j…screw Wire fixing portion; 60k… screw fixing portion; 60m… protrusion; 61… fixing screw of transmission side bracket; 62… receiving substrate bracket; 62a… fixing portion; 62c… positioning portion of protection component; 62d… substrate positioning portion; 62e… hole portion; 62f… second opening; 62j… fixed portion; 62k… positioned portion; 63… fixing screw of receiving side bracket; 65… first surrounding component; 65a… opening; 67… second surrounding component; 70… first protection component; 70a… wire rod; 70b… opening; 71… first holding component; 71a… recessed portion; 71b… opening; 73… second protection component; 74… second holding component; 76… transmission side cable; 77… receiving side cable; 80… control unit; 81… computing unit;82…transport control unit; 83…reading control unit; 84…overfeeding judgment unit; 85…storage unit; 86…interface unit; 87…external device; 100…medium transport device; 210…element substrate; 211…substrate main body; 211A…opening; 211B…partition wall; 212…vibration plate; 212A…vibration unit; 213…base substrate; 220…piezoelectric element; 221…first electrode; 222…piezoelectric film; 223…second electrode; Tr…ultrasonic transducer; R0…upstream feeding path; R1…downstream feeding path; R2…reading transport path; R3…U-turn discharge path. ;

Claims

1. A medium conveying device, characterized in that: have: a first roller pair, which transports the medium in a transport direction; an ultrasonic detection unit arranged downstream of the first roller pair in the conveying direction, In the medium conveying device, the ultrasonic detection unit includes: A transmitting sensor chip, which emits ultrasonic waves along a first axis toward a first surface of a transported medium; a receiving sensor chip, which is arranged at a position on the first axis and separated from the transmitting sensor chip by a medium, and receives ultrasonic waves; a transmitting substrate, on which the transmitting sensor chip is provided; a receiving substrate, on which the receiving sensor chip is disposed; a first protection component, which is a protection component disposed on the first axis and located between the transmitting sensor chip and the medium; a second protection component, which is a protection component disposed on the first axis and located between the receiving sensor chip and the medium; a sending substrate support, which holds the sending substrate and the first protective component; The receiving substrate holder holds the receiving substrate and the second protective member.

2. The medium conveying device according to claim 1, characterized in that: The transmitting substrate support has a first opening, and the first opening allows ultrasonic waves to pass through on the first axis. The first protective member is provided on the surface of the transmission substrate holder so as to cover the first opening. The receiving substrate support has a second opening, and the second opening allows ultrasonic waves to pass through on the first axis. The second protective member is provided on the surface of the receiving substrate holder so as to cover the second opening.

3. The medium conveying device according to claim 1, characterized in that: The transmitting sensor chip and the receiving sensor chip are inclined at a first angle relative to a surface of a medium passing between the transmitting sensor chip and the receiving sensor chip. The first protection member and the second protection member are inclined at a second angle relative to a surface of a medium passing between the transmitting sensor chip and the receiving sensor chip. The first angle is different from the second angle, and the second angle is shallower than the first angle.

4. The medium conveying device according to claim 1, characterized in that: have: a second roller pair arranged downstream of the first roller pair in the conveying direction; a transmission side path forming member, which is a member that forms a medium conveying path between the first roller pair and the second roller pair and fixes the transmission substrate support, The first roller pair includes a separation roller, the separation roller is in contact with the first side of the medium, A detachable cover is provided on the transmission side path forming component. When the cover is installed, the sending substrate support will be covered by the cover. When the cover is removed, the separation roller can be replaced and the sending substrate support is exposed.

5. The medium conveying device according to claim 1, characterized in that: The transmission substrate support has a fixing portion, and the fixing portion fixes the first protection component. The transmitting substrate is fixed to the inner side of the fixing portion. The fixing portion includes a wall portion that is opposed to a side of the fixed transmission substrate and covers at least a portion of the transmission substrate.

6. The medium conveying device according to claim 1, characterized in that: The first protection component and the second protection component are grid-shaped components.

7. The medium conveying device according to claim 6, characterized in that: The opening width of the mesh-shaped member is 30 μm or less.

8. The medium conveying device according to claim 1, characterized in that: A first surrounding member is provided on the transmission substrate. The first surrounding member is a member that surrounds the transmission sensor chip and is a plate-shaped member provided along the transmission substrate. A second surrounding member is provided on the receiving substrate. The second surrounding member is a member that surrounds the receiving sensor chip and is a plate-shaped member provided along the receiving substrate.

9. An image reading device comprising: The medium conveying device according to any one of claims 1 to 8; A reading section is located downstream of the first roller pair in the conveying direction and reads an image of the medium.

Images