Patent Description:
A paper feeding device includes a paper feed tray. A paper bundle in which a plurality of sheets of paper are stacked can be placed on the paper feed tray. For example, a pickup roller may come into contact with an upper surface of the paper bundle placed on the paper feed tray. When the pickup roller rotates, the paper is fed out of the paper feed tray.

Meanwhile, in a paper feeding device, it is necessary to convey one sheet of paper at a time from a paper bundle placed on a paper feed tray. In the paper bundle placed on the paper feed tray, it is necessary to separate an uppermost sheet of paper (hereinafter referred to as an "uppermost sheet of paper") from the paper bundle to prevent paper from being sent out in a state in which a plurality of sheets are overlapping (multiple feeding), see for example <CIT> and <CIT> (each disclosing a sheet feeder comprising a paper feed tray, an air blowing device and an air flow regulation member).

To this end, there is provided a paper feeding device comprising: a paper feed tray on which a paper bundle in which a plurality of sheets of paper are stacked is able to be placed; a blower positioned next to the paper bundle placed on the paper feed tray and able to generate airflow; and a flow regulating member positioned above the paper bundle placed on the paper feed tray, the flow regulating member generating a negative pressure between the flow regulating member and an uppermost sheet of paper of the paper bundle with airflow from the blower.

According to the invention, the flow regulating member has an airfoil shape having a gap, to send airflow between the flow regulating member and the uppermost sheet of paper via the gap.

Preferably, the flow regulating member extends in a direction parallel to a conveying direction of the paper.

Preferably, the flow regulating member extends in a direction parallel to a longitudinal direction of the paper.

Preferably, a plurality of flow regulating members are disposed above the sheet bundle placed on the paper feed tray.

Preferably, the flow regulating members extends in a direction parallel to an upper surface of the uppermost sheet of paper; and a blocking member which blocks airflow from the blower is provided on each of opposite ends of the flow regulating member.

Preferably, a paper position detection unit which is able to detect a position of the uppermost sheet of paper is provided in the flow regulating member.

The paper feeding device may further comprise an air flow rate controller which controls an air flow rate of the blower on the basis of a detection result of the paper position detection unit.

The paper feeding device may further comprise an elevation angle varying mechanism which is able to change an elevation angle of the flow regulating member.

The paper feeding device may further comprise a paper position detection unit which is able to detect a position of the uppermost sheet of paper.

The paper feeding device may further comprise an elevation angle controller which controls the elevation angle varying mechanism on the basis of the detection result of the paper position detection unit.

The paper feeding device may further comprise a relative position varying mechanism which is able to change a relative position between the flow regulating member and the paper feed tray.

The paper feeding device may further comprise a relative position controller which controls the relative position varying mechanism on the basis of the detection result of the paper position detection unit.

Preferably, a heater which is able to heat the uppermost sheet of paper is provided in the flow regulating member.

The paper feeding device may further comprise a sensor which is able to detect at least one of a temperature and humidity of the uppermost sheet of paper.

The paper feeding device may further comprise a heating output controller which controls an output of the heater such that it is in accordance with an air flow rate of the blower on the basis of a detection result of the sensor.

Preferably, a static eliminator which is able to remove static electricity of the uppermost sheet of paper is provided in the flow regulating member.

The paper feeding device may further comprise a voltage output controller which controls an output of the static eliminator such that it is in accordance with an air flow rate of the blower on the basis of the detection result of the sensor.

A paper feeding device of an embodiment includes a paper feed tray, a blower, and a flow regulating member. A paper bundle in which a plurality of sheets of paper are stacked can be placed on the paper feed tray. The blower is positioned next to the paper bundle placed on the paper feed tray. The blower can generate an airflow. The flow regulating member is positioned above the paper bundle placed on the paper feed tray. The airflow from the blower causes the flow regulating member to generate a negative pressure between the flow regulating member and an uppermost sheet of paper of the paper bundle.

Hereinafter, a paper feeding device according to an embodiment will be described with reference to the drawings. In each of the drawings, the same components are designated by the same reference characters.

A paper feeding device will be described.

<FIG> is a perspective view showing a paper feeding device <NUM> of the embodiment. <FIG> is a perspective view showing a cross section of a main portion of the paper feeding device <NUM> of the embodiment. <FIG> is a block diagram showing a configuration of the paper feeding device <NUM> of the embodiment. <FIG> is a view including a cross section taken along line II-II of <FIG>.

As shown in <FIG>, the paper feeding device <NUM> includes a paper feed tray <NUM>, a pickup roller <NUM>, a blower <NUM>, a duct <NUM>, a flow regulating member <NUM>, a blocking member <NUM>, a frame <NUM>, a paper position detection unit <NUM>, a relative position varying mechanism <NUM>, a heater <NUM> (see <FIG>), a sensor <NUM> (see <FIG>), a static eliminator <NUM> (see <FIG>), and a system control unit <NUM> (see <FIG>). For example, the paper feeding device <NUM> is mounted in an image forming device such as a printer.

The paper feed tray <NUM> will be described.

As shown in <FIG>, a paper bundle <NUM> in which a plurality of sheets of paper are stacked can be placed on the paper feed tray <NUM>. The paper is a sheet shaped recording medium. The paper feed tray <NUM> supports the paper bundle <NUM> from below. The paper feed tray <NUM> has a rectangular plate shape corresponding to paper sizes. The paper feed tray <NUM> has a longitudinally-extending part in a paper conveying direction K1 (hereinafter referred to as a "paper conveying direction KI"). The paper feed tray <NUM> feeds unused paper to outside by the pickup roller <NUM>. The paper feed tray <NUM> is disposed in a box-shaped cassette <NUM> which opens upward. The cassette <NUM> can be taken out from the paper feeding device <NUM> in a direction of arrow J1.

The pickup roller <NUM> will be described.

As shown in <FIG>, the pickup roller <NUM> takes out paper from the cassette <NUM>. The pickup roller <NUM> is positioned on a downstream side in the paper conveying direction K1 of an upper portion of the paper bundle <NUM> placed on the paper feed tray <NUM>. The pickup roller <NUM> is in contact with an upper surface 21a of the paper bundle <NUM> placed on the paper feed tray <NUM>. The pickup roller <NUM> is connected to a drive mechanism <NUM> including a motor and the like. When the pickup roller <NUM> is rotated by an operation of the drive mechanism <NUM>, paper is fed out of the paper feed tray <NUM>.

As shown in <FIG>, the blower <NUM> is positioned next to the paper bundle <NUM> placed on the paper feed tray <NUM>. The blower <NUM> can generate airflow. In the embodiment, the blowers <NUM> are disposed next to the both sides of the paper bundle <NUM> placed on the paper feed tray <NUM> in a width direction of the paper (hereinafter referred to as a "paper width direction") perpendicular to the paper conveying direction K1 and parallel to the upper surface 21a of the paper. Each of the blowers <NUM> is positioned at a center in a longitudinal direction of the paper. The blowers <NUM> are fixed at fixed positions.

Hereinafter, one of the blowers <NUM> positioned on one side of the paper bundle <NUM> placed on the paper feed tray <NUM> is referred to as a "first blower 4A" and the other of the blowers <NUM> positioned on the other side of the paper bundle <NUM> placed on the paper feed tray <NUM> is referred to as a "second blower 4B. " Each of the blowers 4A and 4B is disposed so that a blower opening <NUM> (see <FIG>) faces the paper bundle <NUM>.

As shown in <FIG>, the duct <NUM> guides airflow generated by the blowers <NUM> from the side of the paper bundle <NUM> placed on the paper feed tray <NUM> toward the paper bundle <NUM>. In the embodiment, the ducts <NUM> are disposed next to the both sides of the paper bundle <NUM> placed on the paper feed tray <NUM> in the paper width direction.

Hereinafter, one of the ducts <NUM> positioned on one side of the paper bundle <NUM> placed on the paper feed tray <NUM> is referred to as a "first duct 5A" and the other of the ducts <NUM> positioned on the other side of the paper bundle <NUM> placed on the paper feed tray <NUM> is referred to as a "second duct 5B.

The first duct 5A guides the airflow generated by the first blower 4A from the one side toward the paper bundle <NUM>. The first duct 5A forms a flow path of the airflow reaching the paper side from the blower opening <NUM> of the first blower 4A.

The second duct 5B guides the airflow generated by the second blower 4B from the other side toward the paper bundle <NUM>. The second duct 5B forms a flow path of the airflow reaching the paper side from the blower opening <NUM> of the second blower 4B.

The flow regulating member <NUM> will be described.

As shown in <FIG>, the flow regulating member <NUM> is positioned above the paper bundle <NUM> placed on the paper feed tray <NUM>. The airflow from the blowers <NUM> causes the flow regulating member <NUM> to generate a negative pressure between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> of the paper bundle <NUM>. The flow regulating member <NUM> is fixed at a fixed position. A plurality of flow regulating members <NUM> are disposed above the paper bundle <NUM> placed on the paper feed tray <NUM>. The plurality of flow regulating members <NUM> are disposed on opposite sides in the paper width direction above the paper bundle <NUM>. The plurality of flow regulating members <NUM> are a first flow regulating member 6A and a second flow regulating member 6B.

The first flow regulating member 6A is positioned next to the first blower 4A. Airflow from the first blower 4A causes the first flow regulating member 6A to generate a negative pressure between the first flow regulating member 6A and the uppermost sheet of paper <NUM>.

The second flow regulating member 6B is positioned next to the second blower 4B. Airflow from the second blower 4B causes the second flow regulating member 6B to generate a negative pressure between the second flow regulating member 6B and the uppermost sheet of paper <NUM>.

Each of the flow regulating members <NUM> has an airfoil shape. For example, the flow regulating member <NUM> has a shape which is inverted upside down from a wing (main wing) of an airplane. The flow regulating member <NUM> not according to the claimed invention has a continuous airfoil shape without any gap. As shown in <FIG>, the flow regulating member <NUM> extends in a direction parallel to the paper conveying direction K1 (hereinafter also referred to as a "first direction V1"). The flow regulating member <NUM> extends in a direction parallel to the longitudinal direction of the paper. The flow regulating member <NUM> extends in a direction parallel to the upper surface 21a of the uppermost sheet of paper <NUM>. The flow regulating member <NUM> continuously extends in the first direction V1.

<FIG> is a view showing the flow regulating member <NUM> of the embodiment not according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to a cross-sectional view of the flow regulating member <NUM> not according to the claimed invention taken along line II-II of <FIG> when viewed from the first direction V1. In <FIG>, the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

In the following description, the first flow regulating member 6A not according to the claimed invention will be described.

The second flow regulating member 6B is the same as the first flow regulating member 6A, and thus a description thereof will be omitted.

As shown in <FIG>, the first flow regulating member 6A is disposed to be spaced apart from the uppermost sheet of paper <NUM> of the paper bundle <NUM>. A lower portion of the first flow regulating member 6A faces the upper surface 21a of the uppermost sheet of paper <NUM>. Hereinafter, a portion of the first flow regulating member 6A which is close to the first blower 4A is referred to as a "front side" and a portion of the first flow regulating member 6A which is close to the second blower 4B is referred to as a "rear side. " The first flow regulating member 6A is slightly curved to protrude downward with respect to a line connecting a front side end (a front edge) and a rear side end (a rear edge) (hereinafter referred to as a "chord line L1"). The first flow regulating member 6A bulges slightly above a chord line L1 at a front end portion.

An elevation angle A1 of the first flow regulating member 6A is positive. Here, the elevation angle A1 is a value representing an angle at which the first flow regulating member 6A is tilted with respect to a flow of airflow from the first blower 4A. The elevation angle A1 is an angle formed by the chord line L1 and a virtual line L2 passing through the upper surface 21a of the uppermost sheet of paper <NUM>. When the chord line L1 being parallel to the virtual line L2 is taken as a reference, when the front is tilted up, the elevation angle A1 is referred to as being positive. When the elevation angle A1 is positive, a negative pressure tends to be generated between the upper surface 21a of the uppermost sheet of paper <NUM> and the first flow regulating member 6A.

The blocking member <NUM> will be described.

As shown in <FIG>, the blocking members <NUM> are provided at opposite ends of the flow regulating member <NUM>. The blocking members <NUM> block the airflow from the blowers <NUM>. The blocking members <NUM> restrict a flow of airflow so that the airflow passes between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> in regions in which the flow regulating members <NUM> are installed. The blocking members <NUM> have a plate shape parallel to a virtual plane (a vertical plane) perpendicular to an extending direction of the flow regulating members <NUM>. A plurality of blocking members <NUM> are provided in each of the first flow regulating member 6A and the second flow regulating member 6B.

Hereinafter, the blocking member <NUM> provided at one end of the first flow regulating member 6A is referred to as a "first blocking member 7A," the blocking member <NUM> provided at the other end of the first flow regulating member 6A is referred to as a "second blocking member 7B," the blocking member <NUM> provided at one end of the second flow regulating member 6B is referred to as a "third blocking member 7C," and the blocking member <NUM> provided at the other end of the second flow regulating member 6B is referred to as a "fourth blocking member 7D.

As shown in <FIG>, the frame <NUM> is a member forming a framework of the paper feeding device <NUM>. The frame <NUM> supports each element of the paper feeding device <NUM>. The frame <NUM> includes a main body frame <NUM> and an upper frame <NUM>.

The main body frame <NUM> supports the upper frame <NUM> from below. A space <NUM> (see <FIG>) in which the cassette <NUM> is vertically movable is formed inside the main body frame <NUM>.

The upper frame <NUM> supports the blower <NUM>, the duct <NUM> and the flow regulating member <NUM>. The upper frame <NUM> includes a first beam 26a, a second beam 26b, a first connecting beam 26c, a second connecting beam 26d, and a connecting top plate 26e. A gap for discharging airflow from the blower <NUM> to the outside is provided between the upper frame <NUM> and the cassette <NUM>.

The first beam 26a is positioned next to the first blower 4A above the paper bundle <NUM> placed on the paper feed tray <NUM>. The first beam 26a extends in the first direction V1. As shown in <FIG>, the first beam 26a supports the first blower 4A and the first duct 5A via a first bracket <NUM>.

As shown in <FIG>, the second beam 26b is positioned next to the second blower 4B above the paper bundle <NUM> placed on the paper feed tray <NUM>. The second beam 26b extends in a direction parallel to the first beam 26a. The second beam 26b supports the second blower 4B and the second duct 5B via a second bracket <NUM>.

The first connecting beam 26c is positioned on an upstream side in the paper conveying direction K1 above the paper bundle <NUM> placed on the paper feed tray <NUM>. The first connecting beam 26c connects the first beam 26a and the second beam 26b on a position opposite to the pickup roller <NUM>. The first connecting beam 26c extends in a direction parallel to the paper width direction (hereinafter also referred to as a "second direction V2"). The first connecting beam 26c supports one end of the first flow regulating member 6A via the first blocking member 7A. The first connecting beam 26c supports one end of the second flow regulating member 6B via the third blocking member 7C.

The second connecting beam 26d is positioned on the downstream side in the paper conveying direction K1 above the paper bundle <NUM> placed on the paper feed tray <NUM>. The second connecting beam 26d connects the first beam 26a and the second beam 26b at a position next to the pickup roller <NUM>. The second connecting beam 26d extends in a direction parallel to the first connecting beam 26c.

The connecting top plate 26e is positioned on a downstream side in the paper conveying direction K1 above the paper bundle <NUM> placed on the paper feed tray <NUM>. The connecting top plate 26e connects the first beam 26a and the second beam 26b at a position next to the second connecting beam 26d. The connecting top plate 26e supports the other end of the first flow regulating member 6A via the second blocking member 7B. The connecting top plate 26e supports the other end of the second flow regulating member 6B via the fourth blocking member 7D.

The paper position detection unit <NUM> will be described.

As shown in <FIG>, the paper position detection unit <NUM> can detect a position of the uppermost sheet of paper <NUM>. A plurality of paper position detection units <NUM> are provided in each of the connecting top plate 26e and the flow regulating member <NUM>. Hereinafter, the paper position detection unit <NUM> provided on the connecting top plate 26e is referred to as a "top plate side paper position detector 9A," and the paper position detection unit <NUM> provided in the flow regulating member <NUM> is referred to as a "airfoil side paper position detector 9B" (See <FIG>).

The top plate side paper position detector 9A will be described.

As shown in <FIG>, the top plate side paper position detector 9A includes a shaft <NUM>, a contact claw <NUM>, and an infrared sensor <NUM>. For example, the top plate side paper position detector 9A is a contact type displacement sensor.

The shaft <NUM> extends in the second direction V2. Opposite ends of the shaft <NUM> are respectively connected to the first beam 26a and the second beam 26b. Further, the shaft <NUM> may function as a movable shaft when the pickup roller <NUM> moves vertically. In addition, a power transmission mechanism (not shown) such as a belt and a gear which transmits power for rotating the pickup roller <NUM> may be attached to the shaft <NUM>.

The contact claw <NUM> is rotatably attached to the shaft <NUM>. The contact claw <NUM> is constantly in contact with the upper surface 21a of the uppermost sheet of paper <NUM> due to a force-applying member (not shown). A vertical movement of the paper feed tray <NUM> on which the paper bundle <NUM> is placed causes the contact claw <NUM> to rotate around the shaft <NUM> and vertically move together with the upper surface 21a of the uppermost sheet of paper <NUM>.

The infrared sensor <NUM> detects a position of the contact claw <NUM>. The infrared sensor <NUM> detects the position of the uppermost sheet of paper <NUM> by detecting the position of the contact claw <NUM>.

A detection result of the top plate side paper position detector 9A is sent to the system control unit <NUM>.

The airfoil side paper position detector 9B will be described.

As shown in <FIG>, the airfoil side paper position detector 9B is embedded in the flow regulating member <NUM>. The airfoil side paper position detector 9B is provided in each of the first flow regulating member 6A and the second flow regulating member 6B. For example, the airfoil side paper position detector 9B is a non-contact displacement sensor such as a camera and an infrared sensor. The airfoil side paper position detector 9B detects the position of the uppermost sheet of paper <NUM> from a lower surface side of the flow regulating member <NUM>. A detection result of the airfoil side paper position detector 9B is sent to the system control unit <NUM>.

The relative position varying mechanism <NUM> will be described.

As shown in <FIG>, the relative position varying mechanism <NUM> can change the relative position between the flow regulating member <NUM> and the paper feed tray <NUM>. The relative position varying mechanism <NUM> is provided in the main body frame <NUM>. The relative position variable mechanism <NUM> can change the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM>. In the embodiment, the relative position varying mechanism <NUM> changes the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> by vertically moving the cassette <NUM> in a state in which the flow regulating member <NUM> is in a fixed position.

The relative position varying mechanism <NUM> includes a wire <NUM>, a tensioner pulley <NUM>, and an idler pulley <NUM>.

One end of the wire <NUM> is attached to the tensioner pulley <NUM>. The other end of the wire <NUM> is attached to a slider (not shown).

The tensioner pulley <NUM> is rotatable around an axis extending in the second direction V2.

The idler pulley <NUM> movably supports the wire <NUM>. The idler pulley <NUM> allows vertical movement of the wire <NUM>.

A slider (not shown) is attached to the cassette <NUM>. A guide groove <NUM> extending vertically is provided on a side surface of the main body frame <NUM>. The slider is slidably attached to the guide groove <NUM>.

For example, when the tensioner pulley <NUM> rotates in a direction of arrow M1, the slide moves upward along the guide groove <NUM> to lift the cassette <NUM>.

As shown in <FIG>, the heater <NUM> is provided in the flow regulating member <NUM>. The heater <NUM> is provided in each of the first flow regulating member 6A and the second flow regulating member 6B. The heater <NUM> can heat the uppermost sheet of paper <NUM>. For example, the heater <NUM> is a heater such as an infrared lamp heater and a halogen lamp heater. The heater <NUM> heats the uppermost sheet of paper <NUM> from the lower surface side of the flow regulating member <NUM>.

As shown in <FIG>, the sensor <NUM> is embedded in the flow regulating member <NUM>. The sensor <NUM> is provided in each of the first flow regulating member 6A and the second flow regulating member 6B. The sensor <NUM> can detect a temperature and humidity of the uppermost sheet of paper <NUM>. For example, the sensor <NUM> is a non-contact type temperature and humidity sensor. The sensor <NUM> detects the temperature and humidity of the uppermost sheet of paper <NUM> from the lower surface side of the flow regulating member <NUM>. A detection result of the sensor <NUM> is sent to the system control unit <NUM>.

The static eliminator <NUM> will be described.

As shown in <FIG>, the static eliminator <NUM> is embedded in the flow regulating member <NUM>. The static eliminator <NUM> is provided in each of the first flow regulating member 6A and the second flow regulating member 6B. The static eliminator <NUM> can remove static electricity of the uppermost sheet of paper <NUM>. For example, the static eliminator <NUM> is an ionizer. The static eliminator <NUM> applies a high voltage to a discharge needle to cause corona discharge for ionization. The static eliminator <NUM> ionizes air between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> to remove the static electricity of the uppermost sheet of paper <NUM>.

The system control unit <NUM> will be described.

As shown in <FIG>, the system control unit <NUM> generally controls each element of the paper feeding device <NUM>. The system control unit <NUM> includes an air flow rate controller <NUM>, a relative position controller <NUM>, a heating output controller <NUM>, and a voltage output controller <NUM>.

The air flow rate controller <NUM> will be described.

The air flow rate controller <NUM> controls an air flow rate of the blower <NUM> on the basis of a detection result of the paper position detection unit <NUM>. The air flow rate controller <NUM> controls an air flow rate of each of the first blower 4A and the second blower 4B on the basis of respective detection results of the top plate side paper position detector 9A and the airfoil side paper position detector 9B.

For example, when the position of the uppermost sheet of paper <NUM> is higher than a preset threshold value (hereinafter referred to as a "position threshold value"), the air flow rate controller <NUM> decreases the air flow rate of the blower <NUM> so that an air flow rate flowing between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> decreases. When the position of the uppermost sheet of paper <NUM> is lower than the preset position threshold value, the air flow rate controller <NUM> increases the air flow rate of the blower <NUM> so that the air flow rate flowing between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> increases.

The relative position controller <NUM> will be described.

The relative position controller <NUM> controls the relative position varying mechanism <NUM> on the basis of the detection result of the paper position detection unit <NUM>. The relative position controller <NUM> controls the relative position varying mechanism <NUM> on the basis of respective detection results of the top plate side paper position detector 9A and the airfoil side paper position detector 9B.

For example, when the position of the uppermost sheet of paper <NUM> is higher than the position threshold value, the relative position controller <NUM> controls the relative position varying mechanism <NUM> such that the cassette <NUM> (paper feed tray <NUM>) is lowered to a regular position. When the position of the uppermost sheet of paper <NUM> is lower than the position threshold value, the relative position controller <NUM> controls the relative position varying mechanism <NUM> such that the cassette <NUM> is raised to the regular position.

For example, the relative position controller may control the relative position varying mechanism <NUM> such that the cassette <NUM> is raised every time the number of sheets of paper decreases by a predetermined number of sheets (for example, <NUM> sheets).

The heating output controller <NUM> will be described.

A signal related to the air flow rate of the blower <NUM> is sent to the heating output controller <NUM>. The heating output controller <NUM> controls an output of the heater <NUM> such that it is in accordance with the air flow rate of the blower <NUM> on the basis of the detection result of the sensor <NUM>.

For example, when humidity of the uppermost sheet of paper <NUM> is higher than a preset threshold value (hereinafter referred to as a "humidity threshold value"), the heating output controller <NUM> increases the output of the heater <NUM> to heat the uppermost sheet of paper <NUM>. The heating output controller <NUM> decreases the output of the heater <NUM> when humidity of the uppermost sheet of paper <NUM> is lower than the humidity threshold value.

For example, when a temperature of the uppermost sheet of paper <NUM> is lower than a preset threshold value (hereinafter referred to as a "temperature threshold value"), the heating output controller <NUM> increases the output of the heater <NUM> to heat the uppermost sheet of paper <NUM>. The heating output controller <NUM> decreases the output of the heater <NUM> when the temperature of the uppermost sheet of paper <NUM> is higher than the temperature threshold value.

For example, when the air flow rate of the blower <NUM> is higher than a preset threshold value (hereinafter referred to as an "air flow rate threshold value"), the heating output controller <NUM> increases the output of the heater <NUM> to heat the uppermost sheet of paper <NUM>. The heating output controller <NUM> decreases the output of the heater <NUM> when the air flow rate of the blower <NUM> is lower than the air flow rate threshold value.

The voltage output controller <NUM> will be described.

A signal related to the air flow rate of the blower <NUM> is sent to the voltage output controller <NUM>. The voltage output controller <NUM> controls an output of the static eliminator <NUM> such that it is in accordance with the air flow rate of the blower <NUM> on the basis of the detection result of the sensor <NUM>.

For example, when humidity of the uppermost sheet of paper <NUM> is higher than the humidity threshold value, the voltage output controller <NUM> increases the output (voltage applied to the discharge needle) of the static eliminator <NUM> to improve ionization. When the humidity of the uppermost sheet of paper <NUM> is lower than the humidity threshold value, the voltage output controller <NUM> decreases the output of the static eliminator <NUM>.

For example, when a temperature of the uppermost sheet of paper <NUM> is lower than the temperature threshold value, the voltage output controller <NUM> increases the output of the static eliminator <NUM> to improve the ionization. When the temperature of the uppermost sheet of paper <NUM> is higher than the temperature threshold value, the voltage output controller <NUM> decreases the output of the static eliminator <NUM>.

For example, when the air flow rate of the blower <NUM> is higher than the air flow rate threshold value, the voltage output controller <NUM> increases the output of the static eliminator <NUM> to improve the ionization. When the air flow rate of the blower <NUM> is lower than the air flow rate threshold value, the voltage output controller <NUM> decreases the output of the static eliminator <NUM>.

An arrangement of the blower <NUM> and the duct <NUM> will be described.

<FIG> is a view showing an arrangement of the blower <NUM> and the duct <NUM> of the embodiment. <FIG> is a view showing an operation due to the arrangement of the blower <NUM> and the duct <NUM> of the embodiment. In the following description, an arrangement of the first blower 4A and the first duct 5A will be described. Since an arrangement of the second blower 4B and the second duct 5B is the same as the arrangement of the first blower 4A and the first duct 5A, a description thereof will be omitted.

As shown in <FIG>, the first blower 4A and the first duct 5A are disposed such that the blower opening <NUM> faces the upper portion of the paper bundle <NUM>. The first blower 4A and the first duct 5A are disposed next to the upper surface 21a of the uppermost sheet of paper <NUM> of the paper bundle <NUM> in the second direction V2. In <FIG>, reference character F1 shows a virtual plane including the upper surface 21a of the uppermost sheet of paper <NUM>. In a side view of <FIG>, a center of the blower opening <NUM> is disposed to overlap the virtual plane F1.

As shown in <FIG>, the position of the uppermost sheet of paper <NUM> may be lower than a reference position (an initial position) in some cases. For example, as the paper conveying speed (hereinafter referred to as a "processing speed") increases, the position of the uppermost sheet of paper <NUM> tends to be lower. Although the relative position varying mechanism <NUM> (see <FIG>) is provided, when raising the cassette <NUM> when the number of sheets of paper decreases by a predetermined number (for example, <NUM> sheets), the position of the uppermost sheet of paper <NUM> may be lower than the reference position while the number of sheets of paper has decreased by a predetermined number of sheets.

In a case in which a lower end of the blower opening <NUM> is assumed to be disposed to overlap the virtual plane F1, when the position of the uppermost sheet of paper <NUM> is lower than the reference position, there is a likelihood of the blower opening <NUM> being excessively separated from the upper surface 21a of the uppermost sheet of paper <NUM> in the vertical direction.

According to the embodiment, when the center of the blower opening <NUM> is disposed to overlap the virtual plane F1, even when the position of the uppermost sheet of paper <NUM> is lower than the reference position, the blower opening <NUM> remains close to the upper surface 21a of the uppermost sheet of paper <NUM> in the vertical direction (see <FIG>). Therefore, even when the position of the uppermost sheet of paper <NUM> varies, it is possible to efficiently cause airflow between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM>.

A pressure distribution between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> will be described.

<FIG> is a view showing a pressure distribution between the flow regulating member <NUM> not according to the claimed invention and the uppermost sheet of paper <NUM> of the embodiment. <FIG> is a view showing a pressure distribution when the uppermost sheet of paper <NUM> is at a first height H1. <FIG> is a view showing a pressure distribution when the uppermost sheet of paper <NUM> is at a second height H2. <FIG> is a view showing a pressure distribution when the uppermost sheet of paper <NUM> is at a third height H3. Here, the first height H1, the second height H2, and the third height H3 have a relationship of H1<H2<H3. When the flow regulating member <NUM> is at the fixed position, distances G1, G2, and G3 between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> have a relationship of G1>G2>G3.

As shown in <FIG>, a pressure of air between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> is lower than a pressure of a space above the flow regulating member <NUM>. Between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM>, a pressure of air facing a lower center of the flow regulating member <NUM> is the lowest. As the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> becomes smaller, the pressure of the air between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> decreases.

According to the embodiment, the paper feeding device <NUM> has the paper feed tray <NUM>, the blower <NUM>, and the flow regulating member <NUM>. The paper bundle <NUM> in which a plurality of sheets of paper are stacked can be placed on the paper feed tray <NUM>. The blower <NUM> is positioned next to the paper bundle <NUM> placed on the paper feed tray <NUM>. The blower <NUM> can generate airflow. The flow regulating member <NUM> is positioned above the paper bundle <NUM> placed on the paper feed tray <NUM>. The airflow from the blower <NUM> causes the flow regulating member <NUM> to generate a negative pressure between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> of the paper bundle <NUM>. With the above configurations, the following effects are achieved. Since the blower <NUM> is positioned next to the paper bundle <NUM> placed on the paper feed tray <NUM>, it is possible to send airflow between the plurality of sheets of stacked paper as compared with a case in which the blower <NUM> is positioned above the paper bundle <NUM> placed on the paper feed tray <NUM>. In addition, since the airflow from the blower <NUM> causes the flow regulating member <NUM> to generate a negative pressure between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> of the paper bundle <NUM>, the uppermost sheet of paper <NUM> can rise up. Therefore, it is possible to provide the paper feeding device <NUM> capable of separating the uppermost sheet of paper <NUM> from the paper bundle <NUM> placed on the paper feed tray <NUM>.

In addition, since it is possible to reduce an influence of friction and contact between sheets of paper, the paper sheets can be easily taken out one by one. In addition, since a complicated structure such as a shutter mechanism is not required, the paper feeding device <NUM> can be simplified. In addition, since a large-sized fan for generating a large air flow rate is not required, the size of the blower <NUM> can be reduced. In addition, noise reduction can be achieved by reducing the output of the blower <NUM> (a rotation speed of a motor of the blower <NUM>). In addition, the flow regulating member <NUM> can prevent the uppermost sheet of paper <NUM> from excessively rising upward.

Further, since the flow regulating member <NUM> has an airfoil shape, the following effects are achieved. It is easier to generate a high negative pressure (that is, a low pressure) between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> as compared with a case in which the flow regulating member <NUM> has a flat plate shape. Therefore, the uppermost sheet of paper <NUM> can be easily separated from the paper bundle <NUM> placed on the paper feed tray <NUM>.

In addition, since the flow regulating member <NUM> extends in a direction parallel to the paper conveying direction K1, the following effects are achieved. The flow regulating members <NUM> are easily disposed on opposite sides in the paper width direction as compared with a case in which the flow regulating member <NUM> extends in a direction perpendicular to the paper conveying direction K1. Therefore, an arrangement layout of the flow regulating member <NUM> can be improved.

In addition, since the flow regulating member <NUM> extends in a direction parallel to the longitudinal direction of the paper, the following effects are achieved. An inlet port of the airflow from the blower <NUM> can be wider between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> as compared with a case in which the flow regulating member <NUM> extends in a direction parallel to a lateral direction of the paper. Therefore, the uppermost sheet of paper <NUM> easily rises up in a wide range.

Also, since the plurality of flow regulating members <NUM> are disposed above the paper bundle <NUM> placed on the paper feed tray <NUM>, the following effects are achieved. The uppermost sheet of paper <NUM> easily rises up in a wide range as compared with a case in which only one flow regulating member <NUM> is disposed.

In addition, since the plurality of flow regulating members <NUM> are disposed on opposite sides in the paper width direction above the paper bundle <NUM>, the following effects are achieved. The uppermost sheet of paper <NUM> tends to uniformly rise up as a whole as compared with a case in which a plurality of flow regulating members <NUM> are disposed only on one side in the paper width direction.

Further, the flow regulating member <NUM> extends in a direction parallel to the upper surface 21a of the uppermost sheet of paper <NUM>. At opposite ends of the flow regulating member <NUM>, the blocking members <NUM> which block the airflow from the blower <NUM> are provided. With the above configuration, the following effects are achieved. Since the airflow from the blower <NUM> can be blocked by the blocking members <NUM>, it is possible to prevent the airflow from the blower <NUM> from being introduced into an unintended region. Therefore, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>.

In addition, since the airfoil side paper position detector 9B capable of detecting the position of the uppermost sheet of paper <NUM> is provided in the flow regulating member <NUM>, the following effects are achieved. The position of the uppermost sheet of paper <NUM> can be ascertained by the airfoil side paper position detector 9B. In addition, since there is no need to separately provide an independent member for installing the airfoil side paper position detector 9B, it is possible to reduce the number of parts and costs.

In addition, since the airfoil side paper position detector 9B is embedded in the flow regulating member <NUM>, the following effects are achieved. Flow regulating action of the airflow can be secured by the flow regulating member <NUM> as compared with a case in which the airfoil side paper position detector 9B is externally attached to the flow regulating member <NUM>.

Also, since the paper feeding device <NUM> includes the air flow rate controller <NUM> which controls the air flow rate of the blower <NUM> on the basis of the detection result of the paper position detection unit <NUM>, the following effects are achieved. Since the air flow rate of the blower <NUM> can be controlled according to the position of the uppermost sheet of paper <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>.

Incidentally, when the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> is smaller, a force of raising the uppermost sheet of paper <NUM> is improved. For example, from a viewpoint of noise reduction, it is preferable to decrease the air flow rate of the blower <NUM> in a state in which the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> is decreased. For example, from a viewpoint of stabilizing the airflow, it is preferable to increase the air flow rate of the blower <NUM> in a state in which the distance between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> is increased.

Further, since the paper feeding device <NUM> includes the relative position varying mechanism <NUM> capable of changing the relative position between the flow regulating member <NUM> and the paper feed tray <NUM>, the following effects are achieved. Since the distance between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> can be adjusted by the relative position varying mechanism <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>.

Further, the paper feeding device <NUM> includes the top plate side paper position detector 9A and the relative position controller <NUM>. The top plate side paper position detector 9A can detect the position of the uppermost sheet of paper <NUM>. The relative position controller <NUM> controls the relative position varying mechanism <NUM> on the basis of the detection result of the top plate side paper position detector 9A. With the above configuration, the following effects are achieved. The position of the uppermost sheet of paper <NUM> can be ascertained by the top plate side paper position detector 9A. In addition, since the distance between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> can be adjusted according to the position of the uppermost sheet of paper <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>.

Also, since the heater <NUM> capable of heating the uppermost sheet of paper <NUM> is provided in the flow regulating member <NUM>, the following effects are achieved. Since the uppermost sheet of paper <NUM> can be heated by the heater <NUM>, moisture contained in the uppermost sheet of paper <NUM> can be evaporated. Therefore, it is possible to prevent sticking of the plurality of sheets of paper due to the moisture of the uppermost sheet of paper <NUM>. In addition, since there is no need to separately provide an independent member for installing the heater <NUM>, it is possible to reduce the number of parts and costs.

In addition, since the heater <NUM> is embedded in the flow regulating member <NUM>, the following effects are achieved. Flow regulating action of the airflow can be secured by the flow regulating member <NUM> as compared with a case in which the heater <NUM> is externally attached to the flow regulating member <NUM>.

Further, the paper feeding device <NUM> includes the sensor <NUM> and the heating output controller <NUM>. The sensor <NUM> can detect a temperature and humidity of the uppermost sheet of paper <NUM>. On the basis of the detection result of the sensor <NUM>, the heating output controller <NUM> controls the output of the heater <NUM> such that it is in accordance with the air flow rate of the blower <NUM>. With the above configuration, the following effects are achieved. The temperature and humidity of the uppermost sheet of paper <NUM> can be ascertained by the sensor <NUM>. In addition, since the output of the heater <NUM> can be controlled to be in accordance with the air flow rate of the blower <NUM> corresponding to the temperature and humidity of the uppermost sheet of paper <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>. For example, when the air flow rate of the blower <NUM> is higher than the air flow rate threshold value, since the output of the heater <NUM> can be increased to heat the uppermost sheet of paper <NUM>, the temperature of the uppermost sheet of paper <NUM> being lowered due to the airflow of the blower <NUM> can be prevented.

In addition, since the sensor <NUM> is embedded in the flow regulating member <NUM>, the following effects are achieved. Flow regulating action of the airflow can be secured by the flow regulating member <NUM> as compared with a case in which the sensor <NUM> is externally attached to the flow regulating member <NUM>.

Also, since the static eliminator <NUM> capable of removing the static electricity of the uppermost sheet of paper <NUM> is provided in the flow regulating member <NUM>, the following effects are achieved. Since static electricity of the uppermost sheet of paper <NUM> can be removed by the static eliminator <NUM>, it is possible to prevent sticking of the plurality of sheets of paper due to the static electricity of the uppermost sheet of paper <NUM>. In addition, since there is no need to separately provide an independent member for installing the static eliminator <NUM>, it is possible to reduce the number of parts and costs.

In addition, since the static eliminator <NUM> is embedded in the flow regulating member <NUM>, the following effects are achieved. Flow regulating action of the airflow can be secured by the flow regulating member <NUM> as compared with a case in which the static eliminator <NUM> is externally attached to the flow regulating member <NUM>.

Further, since the paper feeding device <NUM> includes the voltage output controller <NUM> which controls the output of the static eliminator <NUM> such that it is in accordance with the air flow rate of the blower <NUM> on the basis of the detection result of the sensor <NUM>, the following effects are achieved. In addition, since the output of the static eliminator <NUM> can be controlled to be in accordance with the air flow rate of the blower <NUM> corresponding to the temperature and humidity of the uppermost sheet of paper <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>. For example, when the air flow rate of the blower <NUM> is higher than the air flow rate threshold value, since the output of the static eliminator <NUM> can be increased to improve the ionization, decrease in action of electrically charged air (static elimination effect) due to the airflow of the blower <NUM> can be minimized.

Modified examples of the embodiment will be described below.

A first modified example of the embodiment will be described.

In the embodiment, the case in which the flow regulating member <NUM> has an airfoil shape and bulges slightly above the chord line L1 at the front end portion has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing a flow regulating member <NUM> of the first modified example of the embodiment not according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to <FIG> in which a cross section of the flow regulating member <NUM> taken along line II-II of <FIG> is viewed from the first direction V1. In <FIG>, the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

As shown in <FIG>, the flow regulating member <NUM> has no bulging portion bulging slightly above the chord line L1 at the front end portion. An upper surface 106a of the flow regulating member <NUM> may be parallel to the chord line L1. The chord line L1 may be parallel to the virtual line L2.

According to the first modified example, since the upper surface 106a of the flow regulating member <NUM> is parallel to the chord line L1, the following effects are achieved. The shape of the flow regulating member <NUM> can be simplified as compared with a case in which the flow regulating member has a bulging portion.

A second modified example of the embodiment will be described.

In the embodiment, the case in which the flow regulating member <NUM> has the airfoil shape has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing a flow regulating member <NUM> of the second modified example of the embodiment not according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to <FIG> in which a cross section of the flow regulating member <NUM> taken along line II-II of <FIG> is viewed from the first direction V1. In <FIG>, the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

As shown in <FIG>, the flow regulating member <NUM> may have a flat plate shape. The elevation angle A1 of the flow regulating member <NUM> is positive.

According to the second modified example, since the flow regulating member <NUM> has a flat plate shape, the following effects are achieved. The shape of the flow regulating member <NUM> can be simplified as compared with a case in which the flow regulating member has an airfoil shape.

A third modified example of the embodiment will be described.

In the embodiment, the case not according to the claimed invention in which the flow regulating member <NUM> has a continuous airfoil shape without a gap has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing a flow regulating member <NUM> of the third modified example of the embodiment according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to <FIG> in which a cross section of the flow regulating member <NUM> taken along line II-II of <FIG> is viewed from the first direction V1. In <FIG>, illustrations of the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

As shown in <FIG>, the flow regulating member <NUM> has a segmented airfoil shape having a gap <NUM>.

The flow regulating member <NUM> includes a first flow regulating portion 306a, a second flow regulating portion 306b, and a coupling portion 306c.

The first flow regulating portion 306a is positioned on a front side of the flow regulating member <NUM>.

The second flow regulating portion 306b is positioned on a rear side of the flow regulating member <NUM>.

The coupling portion 306c couples the first flow regulating portion 306a and the second flow regulating portion 306b. The coupling portion 306c is positioned at an end portion in an extending direction of the flow regulating member <NUM>.

A gap <NUM> is provided between the first flow regulating portion 306a and the second flow regulating portion 306b. In the cross-sectional view of <FIG>, the gap <NUM> is curved to be positioned lower toward the rear side.

According to the third modified example, since the flow regulating member <NUM> has a segmented airfoil shape having the gap <NUM>, the following effects are achieved.

It is possible to send airflow between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> via the gap <NUM>. Therefore, the air flow rate flowing between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> can be increased as compared with a case in which a flow regulating member has a continuous airfoil shape without a gap.

A fourth modified example of the embodiment will be described.

In the embodiment, the case in which the flow regulating member <NUM> is fixed to the fixed position has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing the flow regulating member <NUM> of the fourth modified example of the embodiment not according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to <FIG> in which a cross section of the flow regulating member <NUM> taken along line II-II of <FIG> is viewed from the first direction V <NUM>. In <FIG>, the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

As shown in <FIG>, an elevation angle of the flow regulating member <NUM> may be changeable.

The paper feeding device of the present modified example further includes an elevation angle varying mechanism <NUM> and an elevation angle controller <NUM>.

The elevation angle varying mechanism <NUM> can change the elevation angle of the flow regulating member <NUM>. The elevation angle varying mechanism <NUM> is attached to the flow regulating member <NUM>. The elevation angle varying mechanism <NUM> rotates the flow regulating member <NUM> around a support shaft <NUM>. For example, the elevation angle varying mechanism <NUM> includes a motor capable of rotating forward and backward.

The elevation angle controller <NUM> controls the elevation angle varying mechanism <NUM> on the basis of the detection result of the top plate side paper position detector 9A. For example, the elevation angle controller <NUM> determines the mass of the uppermost sheet of paper <NUM> from a rising-up amount of the uppermost sheet of paper <NUM> or the like on the basis of the detection result of the top plate side paper position detector 9A.

For example, when the uppermost sheet of paper <NUM> is heavier than a preset threshold value (hereinafter referred to as a "mass threshold value"), the elevation angle controller <NUM> sets the elevation angle to be positive, and thereby facilitating generation of a negative pressure between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM>.

For example, when the uppermost sheet of paper <NUM> is lighter than the mass threshold value, the elevation angle controller <NUM> sets the elevation angle to be negative, thereby making it difficult for a negative pressure to be generated between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM>.

According to the fourth modified example, since the elevation angle varying mechanism <NUM> capable of changing the elevation angle of the flow regulating member <NUM> is provided, the following effect is achieved. It is possible to adjust a magnitude of the negative pressure generated between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> as compared with the case in which the flow regulating member <NUM> is fixed at the fixed position.

Also, since the paper feeding device includes the elevation angle controller <NUM> which controls the elevation angle varying mechanism <NUM> on the basis of the detection result of the top plate side paper position detector 9A, the following effects are achieved. Since the elevation angle can be changed according to the position of the uppermost sheet of paper <NUM>, the uppermost sheet of paper <NUM> can be stably separated from the paper bundle <NUM> placed on the paper feed tray <NUM>. For example, the mass of the uppermost sheet of paper <NUM> is determined from a rising-up amount of the uppermost sheet of paper <NUM> or the like, and when the uppermost sheet of paper <NUM> is heavier than the mass threshold value, the elevation angle can be set to plus. Therefore, a decrease in action of the flow regulating member <NUM> (rising-up effect) due to a weight of the uppermost sheet of paper <NUM> can be prevented.

Further, the elevation angle controller <NUM> is not limited to determining the mass of the uppermost sheet of paper <NUM> from the rising-up amount of the uppermost sheet of paper <NUM> and the like. For example, the elevation angle controller <NUM> may determine the mass of the uppermost sheet of paper <NUM> from an imaging result of a camera or the like which images the uppermost sheet of paper <NUM>.

A fifth modified example of the embodiment will be described.

<FIG> is a view showing the flow regulating member <NUM> of the fifth modified example of the embodiment not according to the claimed invention together with the paper bundle <NUM>. <FIG> corresponds to <FIG> in which a cross section of the flow regulating member <NUM> taken along line II-II of <FIG> is viewed from the first direction V1. In <FIG>, the paper feed tray <NUM>, the blower <NUM>, and the like are omitted.

As shown in <FIG>, the flow regulating member <NUM> may be swingable. A swing mechanism <NUM> capable of swinging the flow regulating member <NUM> is attached to the flow regulating member <NUM>. For example, the swing mechanism <NUM> is a slider crank mechanism.

According to the fifth modified example, since the swing mechanism <NUM> capable of swinging the flow regulating member <NUM> is provided, the following effect is achieved. It is possible to change a magnitude of the negative pressure generated between the upper surface 21a of the uppermost sheet of paper <NUM> and the flow regulating member <NUM> as compared with the case in which the flow regulating member <NUM> is fixed at the fixed position.

A sixth modified example of the embodiment will be described.

In the embodiment, the case in which a plurality of the flow regulating members <NUM> are disposed above the paper bundle <NUM> placed on the paper feed tray <NUM> has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing a flow regulating member <NUM> of the sixth modified example of the embodiment together with the paper bundle <NUM> and a blower <NUM>. In <FIG>, an illustration of the paper feed tray <NUM> or the like is omitted.

As shown in <FIG>, only one flow regulating member <NUM> may be disposed above the paper bundle <NUM>. The flow regulating member <NUM> is disposed on one side in the paper width direction above the paper bundle <NUM>.

According to the sixth modified example, since only one flow regulating member <NUM> is disposed above the paper bundle <NUM>, the following effect is achieved. It is possible to reduce the number of parts and costs as compared with the case in which a plurality of the flow regulating members <NUM> are disposed above the paper bundle <NUM>.

A seventh modified example of the embodiment will be described.

In the embodiment, the case in which the flow regulating member <NUM> continuously extends in the first direction V1 has been described, but the present embodiment is not limited thereto.

<FIG> is a view showing a flow regulating member <NUM> of the seventh modified example of the embodiment together with the paper bundle <NUM> and a blower <NUM>. In <FIG>, an illustration of the paper feed tray <NUM> or the like is omitted.

As shown in <FIG>, the flow regulating member <NUM> may be segmented and extend in the first direction V1.

The flow regulating member <NUM> includes a first flow regulating portion 706a, a second flow regulating portion 706b, and a coupling portion 706c.

The first flow regulating portion 706a is positioned on the upstream side in the paper conveying direction K1.

The second flow regulating portion 706b is positioned on the downstream side in the paper conveying direction K1.

The coupling portion 706c couples the first flow regulating portion 706a and the second flow regulating portion 706b. The coupling portion 706c is positioned between the first flow regulating portion 706a and the second flow regulating portion 706b.

Two blowers <NUM> are disposed next to the paper bundle <NUM> placed on the paper feed tray <NUM>. The two blowers <NUM> are respectively positioned next to the first flow regulating portion 706a and the second flow regulating portion 706b.

According to the seventh modified example, since the flow regulating member <NUM> is segmented and extends in the first direction V <NUM>, the following effect is achieved. It is possible to send airflow between the segmented flow regulating members <NUM> (the first flow regulating portion 706a and the second flow regulating portion 706b) and the uppermost sheet of paper <NUM>. For example, even when a paper size is larger than a preset threshold value (hereinafter referred to as a "size threshold value") (for example, A3 size or more), the uppermost sheet of paper <NUM> can be stably separated.

An eighth modified example of the embodiment will be described.

<FIG> is a perspective view showing a flow regulating member <NUM> of the eighth modified example of the embodiment not according to the claimed invention.

As shown in <FIG>, a plurality of protruding portions <NUM> protruding downward may be provided in the flow regulating member <NUM>.

In <FIG>, two protruding portions <NUM> are shown. The number of protruding portions <NUM> may be one, three or more.

The protruding portions <NUM> protrude from a lower surface of the flow regulating member <NUM> toward the uppermost sheet of paper <NUM>. Lower ends of the protruding portions <NUM> are separated from the upper surface 21a of the uppermost sheet of paper <NUM>. The two protruding portions <NUM> are disposed at an interval in the first direction V <NUM>. The protruding portions <NUM> extend in the second direction V2. The protruding portions <NUM> have a plate shape having a thickness in the first direction V1.

According to the eighth modified example, since the protruding portions <NUM> protruding downward are provided in the flow regulating member <NUM>, the following effect is achieved. The protruding portions <NUM> can restrain excessive rising-up of the uppermost sheet of paper <NUM>.

A ninth modified example of the embodiment will be described.

In the eighth modified example of the embodiment, the case in which the protruding portions <NUM> have a plate shape has been described, but the present embodiment is not limited thereto.

<FIG> is a perspective view showing a flow regulating member <NUM> of the ninth modified example of the embodiment not according to the claimed invention.

As shown in <FIG>, a protruding portion <NUM> may have a columnar shape extending from a lower surface of the flow regulating member <NUM> toward the uppermost sheet of paper <NUM>. A lower end of the protruding portion <NUM> is separated from the upper surface 21a of the uppermost sheet of paper <NUM>.

In <FIG>, one protruding portion <NUM> is shown. The number of protruding portions <NUM> may be two or more. For example, a plurality of protruding portions <NUM> may be disposed at intervals in the first direction V1 or the second direction V2.

According to the ninth modified example, since the protruding portion <NUM> protruding downward is provided in the flow regulating member <NUM>, the following effect is achieved. The protruding portion <NUM> can restrain excessive rising-up of the uppermost sheet of paper <NUM>.

Further, in the above-described embodiment, a case in which the paper feeding device is applied to an image forming device such as a printer has been described, but the present embodiment is not limited thereto. For example, the paper feeding device may be applied to financial instruments, postal sorting machines, printing machines, copying machines, facsimile machines, multi-function peripherals, and the like. Further, the multi-function peripherals may be for business use or office use and include various types of paper.

Further, in the above-described embodiment, the case in which the flow regulating member extends in the direction parallel to the paper conveying direction has been described, but the present embodiment is not limited thereto. For example, the flow regulating member may extend in a direction intersecting the paper conveying direction.

Further, in the above-described embodiment, the case in which the flow regulating member extends in a direction parallel to the longitudinal direction of the paper has been described, but the present embodiment is not limited to this. For example, the flow regulating member may extend in a direction intersecting the longitudinal direction of the paper.

Further, in the above-described embodiment, the case in which two flow regulating members are disposed above the paper bundle has been described, but the present embodiment is not limited thereto. For example, three or more flow regulating members may be disposed above the paper bundle.

Further, in the above-described embodiment, the case in which the blocking members which block airflow from the blower are provided at opposite ends of the flow regulating member has been described, but the present embodiment is not limited thereto. For example, no blocking member may be provided at opposite ends of the flow regulating member. For example, opposite ends of the flow regulating member may be directly supported by the frame.

Further, in the above-described embodiment, the case in which the flow regulating member is supported by the frame has been described, but the present embodiment is not limited thereto. For example, the flow regulating member may be supported by the cassette.

Further, in the above-described embodiment, the case in which the airfoil side paper position detector, the heater, the sensor, and the static eliminator are embedded in the flow regulating member has been described, but the present embodiment is not limited thereto. For example, at least one of the airfoil side paper position detector, the heater, the sensor, and the static eliminator may be externally attached to the flow regulating member. Alternatively, at least one of the airfoil side paper position detector, the heater, the sensor, and the static eliminator may be supported by a member other than the flow regulating member such as the frame and the cassette.

Further, in the above-described embodiment, the case in which the blower is fixed at the fixed position has been described, but the present embodiment is not limited thereto. For example, the blower may be movable in an extending direction of the flow regulating member. Since the blower is movable in the extending direction of the flow regulating member, even when the paper size is larger than the size threshold value, the uppermost sheet of paper can be stably separated.

Also, in the above-described embodiment, the case in which the relative position varying mechanism changes the distance between the upper surface of the uppermost sheet of paper and the flow regulating member by vertically moving the cassette in a state in which the flow regulating member is at the fixed position has been described, but the present embodiment is not limited thereto. For example, the relative position varying mechanism may change the position of the flow regulating member with respect to the uppermost sheet of paper by moving the flow regulating member in a virtual plane (in a vertical plane) perpendicular to the extending direction of the flow regulating member in a state in which the paper feed tray is at a regular position. Since the flow regulating member is moved, it is possible to prevent the flow regulating member from causing a becoming when taking out the cassette.

For example, the relative position controller may control the relative position varying mechanism on the basis of a processing speed. The faster the processing speed, the wider the distance between the upper surface of the uppermost sheet of paper and the flow regulating member. For example, the relative position controller may move the flow regulating member toward the upper surface of the uppermost sheet of paper by an amount corresponding to an increase in the distance between the upper surface of the uppermost sheet of paper and the flow regulating member.

Further, in the above-described embodiment, the case in which the sensor can detect a temperature and humidity of the uppermost sheet of paper has been described, but the present embodiment is not limited thereto. For example, the sensor may be able to detect only a temperature of the uppermost sheet of paper. Alternatively, the sensor may be able to detect only humidity of the uppermost sheet of paper. That is, the sensor may be capable of detecting at least one of the temperature and humidity of the uppermost sheet of paper.

Further, in the above-described embodiment, the case in which the system control unit controls each element of the blower, the elevation angle varying mechanism, the relative position varying mechanism, the heater, and the static eliminator has been described, but the present embodiment is not limited thereto. For example, at least one of the above elements may be manually operated.

According to at least one embodiment described above, it is possible to provide a paper feeding device <NUM> capable of separating the uppermost sheet of paper <NUM> from the paper bundle <NUM> placed on the paper feed tray <NUM> by including the paper feed tray <NUM> on which the paper bundle <NUM> in which a plurality of sheets of paper are stacked can be placed, the blower <NUM> positioned next to the paper bundle <NUM> placed on the paper feed tray <NUM> and capable of generating airflow, and the flow regulating member <NUM> positioned above the paper bundle <NUM> placed on the paper feed tray <NUM> and generating a negative pressure between the flow regulating member <NUM> and the uppermost sheet of paper <NUM> of the paper bundle <NUM> by the airflow from the blower <NUM>.

Claim 1:
A paper feeding device (<NUM>) comprising:
a paper feed tray (<NUM>) on which a paper bundle (<NUM>) in which a plurality of sheets of paper are stacked is able to be placed;
a blower (<NUM>) positioned next to the paper bundle (<NUM>) placed on the paper feed tray (<NUM>) and able to generate airflow; and
a flow regulating member (<NUM>) positioned above the paper bundle (<NUM>) placed on the paper feed tray (<NUM>), the flow regulating member (<NUM>) generating a negative pressure between the flow regulating member (<NUM>) and an uppermost sheet of paper of the paper bundle (<NUM>) with airflow from the blower (<NUM>),
characterized in that the flow regulating member (<NUM>) has a segmented airfoil shape having a gap (<NUM>), to send airflow between the flow regulating member and the uppermost sheet of paper (<NUM>) via the gap (<NUM>).