JP2019011150A - Air paper feeder, and paper-feeding tray elevating/lowering control method for air paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a position of a paper feed table based on a floating state including a succeeding paper in an air paper feed device with a simple configuration. SOLUTION: A paper feed table that can be raised and lowered, a blower mechanism that outputs air for floating the paper placed on the paper feed table, a sensor window arranged on the side surface side of the paper, and a sensor window. It includes a photoelectric sensor that emits light and detects the amount of reflected light, and controls the raising and lowering operation of the paper feed table based on the detection result of the photoelectric sensor when the paper condition detector fixedly attached and the blower mechanism are operating. An air paper feed device equipped with a paper feed control unit. [Selection diagram] Fig. 1

Description

  The present invention relates to an air sheet feeding device used in an image forming apparatus or the like and a sheet feeding table lifting control method in the air sheet feeding device.

  An image forming apparatus such as a printing apparatus or a copying apparatus includes a sheet feeding apparatus that feeds sheets one by one from a bundle of sheets loaded on a sheet feeding table to an image forming unit. 2. Description of the Related Art Conventionally, in a paper feeding device, a system in which a rotating paper feeding roller is brought into contact with the uppermost sheet, the uppermost sheet is separated from a bundle by a frictional force, and the sheet is fed out.

  In recent years, an air paper feeding method has been put into practical use in which the uppermost paper is lifted using air to separate the paper from the bundle and feed the paper. In the air feeding method, the uppermost sheet that has been floated by blowing air is sucked by a conveying belt having an air inlet for sucking air and conveyed toward an image forming mechanism.

  In such an air feeding system, for example, upper surface detection for detecting the position of the uppermost sheet is performed in order to raise the uppermost sheet to an appropriate height for feeding. Then, when the uppermost sheet position is too low, the sheet feeding table is raised, and when the uppermost sheet position is too high, sheet feeding table position control is performed to lower the sheet feeding table.

JP 2010-89955 A JP 2005-104723 A

  In recent years, image forming apparatuses have been increased in speed, and a paper feed speed has been increased. In order to be able to perform continuous paper feeding quickly, it is not enough to lift only the topmost sheet, it is effective to float several subsequent sheets and wait appropriately around the conveyor belt It is.

  When several subsequent sheets are lifted and are properly kept in the vicinity of the transport belt, it is not sufficient to detect the position of the topmost sheet before rising, and the paper including the subsequent sheets at the time of rising It is required to control the position of the paper feed table by grasping the floating state of the paper.

  For example, it is conceivable to grasp the floating state of the paper including the succeeding paper by capturing the paper at the time of floating from the side end direction and recognizing each paper by image analysis. It will cause an increase.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make it possible to perform a paper feed stand position control based on a floating state including a succeeding paper with a simple configuration in an air paper feeder.

  In order to solve the above problems, a sheet feeding device according to an aspect of the present invention includes a sheet feeding table that can be moved up and down, and a blower mechanism that outputs air for floating a sheet placed on the sheet feeding table, A paper state detection unit fixedly including a sensor window disposed on a side surface of the paper and a photoelectric sensor that emits light toward the sensor window and detects a reflected light amount, and an operation of the blower mechanism In some cases, a paper feed control unit that controls the raising and lowering operation of the paper feed base based on the detection result of the photoelectric sensor is provided.

  According to the present invention, in the air sheet feeding device, the sheet feeding table position control based on the floating state including the succeeding sheet can be performed with a simple configuration.

1 is a block diagram illustrating a configuration of an image forming apparatus to which an air sheet feeding device according to an embodiment is applied. FIG. 3 is a block diagram illustrating a configuration of a paper state detection unit. 6 is a flowchart for explaining a sheet feeding table lifting operation in the air sheet feeding device. It is a figure explaining the paper state seen from the sensor window at the time of ventilation stop, and a sensor value. It is a figure explaining the paper state and sensor value which were seen from the sensor window at the time of ventilation.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of an image forming apparatus 10 to which an air sheet feeding device 100 according to the present embodiment is applied. The air feeding device 100 feeds the paper by blowing air from the side surface direction to the upper part of the paper stack placed on the paper feed table and floating it.

  The image forming apparatus 10 can be applied to a printing apparatus, a copying apparatus, a facsimile apparatus, and the like. The image forming apparatus 10 includes an image forming unit 12 and forms an image on a sheet supplied from the air feeding device 100. The image forming method of the image forming unit 12 is arbitrary, and can be, for example, an ink jet method, an electrophotographic method, a stencil method, or the like.

  Further, the term “paper” supplied by the air paper feeder 100 is for convenience, and is not limited to paper, but is a concept that includes a sheet-like material capable of forming an image on a film or other surface.

  As shown in the figure, the air sheet feeder 100 includes a sheet feeding table 110, a sheet feeding table raising / lowering mechanism 120, a floating air blowing mechanism 130, a separation air blowing mechanism 140, a suction type conveying belt 150, a suction mechanism 152, a sheet feeding mechanism. A control unit 160 and a paper state detection unit 170 are provided.

  The paper feed table 110 places the paper 200 in a stacked state. Among the paper sheets 200 placed on the paper feed tray 110, the top several sheets are floated by air, and the uppermost paper sheet 200a is separated and adsorbed to the suction type conveyance belt 150. The sheet adsorbed by the suction type conveyance belt 150 is conveyed toward the image forming unit 12. A sheet 201 in the drawing schematically represents a state in which the sheet 201 is being conveyed by the suction type conveyance belt 150 toward the image forming unit 12.

  The paper feed table elevating mechanism 120 drives the paper feed table 110 to perform an elevating operation based on the control of the paper feed control unit 160. By the lifting / lowering operation of the sheet feed lifting mechanism 120, the position of the loaded paper 200 moves up and down. The system of the raising / lowering mechanism of the paper feed table raising / lowering mechanism 120 does not matter. For example, a motor-driven gear type, a hydraulic type, or the like can be used.

  The floating air blowing mechanism 130 is a mechanism that outputs air for floating the top several sheets of the paper 200 placed on the paper feed table 110. For this reason, an air outlet is provided on the side surface of the paper 200 above the paper feed tray 110.

  The separation air blowing mechanism 140 is a mechanism that outputs air for separating the uppermost sheet 200 a from the plurality of sheets 200 raised by the floating air blowing mechanism 130. For this reason, it has an air blower outlet narrower in the horizontal direction above the opening of the floating air blowing mechanism 130. Both the floating air blowing mechanism 130 and the separation air blowing mechanism 140 perform a blowing operation under the control of the paper feed control unit 160.

  The height direction of the uppermost sheet 200a when the blowing is stopped in order to reliably feed the sheets 200 one by one by blowing air from the floating air blowing mechanism 130 and the separation air blowing mechanism 140. There is an appropriate state between the position of the upper sheet and the floating state of the upper sheet during blowing. In the present embodiment, this appropriate state is realized by raising / lowering control of the paper feed tray 110.

  The suction type conveyance belt 150 is an endless belt in which a large number of holes for air suction are formed, and is driven to rotate by a roller. A suction mechanism 152 is disposed inside the suction type conveyance belt 150, and adsorbs the sheet 201 to the outside of the suction type conveyance belt 150 and conveys it toward the image forming unit 12. In other words, the uppermost sheet 200 a of the sheets 200 placed on the sheet feeding table 110 is sequentially sucked and conveyed by the suction type conveying belt 150.

  The paper feed control unit 160 can be composed of a computing device such as a microcomputer, and controls the paper feed operation in the air paper feed device 100. In the present embodiment, in particular, based on the detection result of the paper state detection unit 170, the paper feed table lifting mechanism is operated to control the position of the paper feed table 110.

  In controlling the position of the paper feed table 110, the paper feed control unit 160 evaluates the current position of the paper feed table 110, and two types of reference values for the sensor value C1 output by the paper status detection unit 170. X0 and X1 are set. The reference value X0 and the reference value X1 may be the same value or different values.

  The reference value X0 is a value for evaluating the position of the paper feed tray 110 when air is not being blown, and the reference value X1 is a value for evaluating the position of the paper feed tray 110 when air is being blown. The reference value X0 and the reference value X1 may be values having a width. Further, the reference value X0 and the reference value X1 may be different values depending on the paper type and the like.

  The paper state detection unit 170 detects the state of the paper placed on the paper feed tray 110 and is fixedly attached near the air outlet of the floating air blowing mechanism 130. FIG. 2 is a block diagram illustrating a configuration of the paper state detection unit 170.

  As shown in the figure, the paper state detection unit 170 includes a sensor window 174 and a photoelectric sensor 171. The sensor window 174 is arranged on the side surface side of the paper 200 placed on the paper feed table 110. The sensor window 174 has such a size that the floating state of several upper sheets 200 that are floating by the floating air blowing mechanism 130 can be observed. Further, the uppermost sheet 200a that is not lifted is placed at a position where the proper position is accommodated.

  The photoelectric sensor 171 includes a light emitting unit 172 and a light receiving unit 173. For example, a light emitting diode or the like can be used for the light emitting unit 172, and the light emitting unit 172 emits light toward the sensor window 174. The emitted light can be, for example, infrared light. Other light such as visible light may be used. The sensor window 174 is made of a material that transmits light output from the light emitting unit 172. It may be a cavity. On the other hand, the periphery of the sensor window 174 is made of a material that blocks light output from the light emitting unit 172.

  For example, a photodiode or the like can be used as the light receiving unit 173. The reflected light of the light output from the light emitting unit 172 is detected, converted into a physical quantity corresponding to the light amount, for example, a voltage value, and output as a sensor value C1. . That is, it operates as an illuminance sensor that detects the average amount of light in the sensor window 174.

  Here, it is assumed that the output voltage of the light receiving unit 173 increases as the amount of received light increases. Since the light received by the light receiving unit 173 is mainly reflected light from the paper 200 present in the sensor window 174 portion, the amount of light received increases as the amount and density of the paper 200 present in the sensor window 174 portion increases. The sensor value C1 output from the light receiving unit 173 increases.

  The photoelectric sensor 171 may be attached obliquely to the side surface of the sheet bundle or may be attached straight. Further, since the photoelectric sensor 171 does not contact the paper 200, the photoelectric sensor 171 does not affect the floating of the paper 200.

  Next, the sheet feeding table raising / lowering operation in the air sheet feeder 100 having the above configuration will be described with reference to the flowchart of FIG. This operation is executed under the control of the paper feed control unit 160 at the start of printing, for example.

  First, the paper feed control unit 160 activates the paper state detection unit 170 prior to the blowing operation by the floating air blowing mechanism 130 and the separation air blowing mechanism 140 (S101). That is, light is output from the light emitting unit 172 of the photoelectric sensor 171 and measurement is performed by the light receiving unit 173.

  Then, the sensor value C1 output from the photoelectric sensor 171 is acquired (S102), and the magnitude is compared with the reference value X0 (S103). As described above, the reference value X0 may be a value having a width.

  Here, the reference value X0 is an output value of the photoelectric sensor 171 when the uppermost sheet 200a that is not floating is in an appropriate position. The reference value X0 is predetermined theoretically and experimentally during design and development. The value may be adjusted for each individual.

  For example, if it is appropriate that the uppermost sheet 200a of the sheet 200 viewed from the sensor window 174 is in the position shown in FIG. 4A, the sensor value at that time is set as the reference value X0. In this case, as shown in FIG. 4B, if the position of the paper feed tray 110 is too low and the uppermost paper 200a is lower than the appropriate position, the amount of reflected light from the paper 200 becomes small. It becomes smaller than the reference value X0. On the other hand, as shown in FIG. 4C, if the position of the paper feed tray 110 is too high and the uppermost paper 200a is higher than the appropriate position, the amount of reflected light from the paper 200 increases, and therefore the sensor value C1 is the reference value. It becomes larger than the value X0.

  For this reason, when the sensor value C1 is smaller than the reference value X0, the paper feed controller 160 operates the paper feed platform elevating mechanism 120 to raise the paper feed platform 110 (S104). On the contrary, when the sensor value C1 is larger than the reference value X0, the paper feed table elevating mechanism 120 is operated to lower the paper feed table 110 (S105).

  The paper feed controller 160 repeats this process until the sensor value C1 becomes equal to the reference value X0 (including the case where the sensor value C1 falls within the reference value range X0). When the sensor value C1 becomes equal to the reference value X0, the lifting / lowering operation of the paper feed tray 110 is stopped (S106). As a result, the vertical position of the uppermost sheet 200a is optimized when the blowing is stopped.

  The paper feed control unit 160 starts the blowing operation by the floating air blowing mechanism 130 and the separation air blowing mechanism 140 when the vertical position of the uppermost sheet 200a is optimized when the blowing is stopped (S107). Then, paper feeding is started (S108). Specifically, the uppermost sheet 200 a that has been floated by the floating air blowing mechanism 130 and separated by the separation air blowing mechanism 140 is adsorbed by the suction-type conveyance belt 150 and conveyed to the image forming unit 12.

  The paper feed control unit 160 optimizes the state of the floating paper 200 during paper feeding. Therefore, the sensor value C1 output from the photoelectric sensor 171 is acquired (S109), and the magnitude is compared with the reference value X1 (S110). As described above, the reference value X1 may be a value having a width.

  Here, the reference value X1 is an output value of the photoelectric sensor 171 when the state of the floating sheet 200 is appropriate. The state of the flying sheet 200 is represented by the number of flying sheets, the sheet interval, the flying position, and the like. Similarly to the reference value X0, the reference value X1 is predetermined theoretically and experimentally during design and development. The value may be adjusted for each individual.

  For example, if the floating state of the sheet 200 viewed from the sensor window 174 is appropriate as shown in FIG. 5A, the sensor value at that time is set as the reference value X1. In this case, as shown in FIG. 5 (b), if the position of the paper feed tray 110 is too low, the paper density in the sensor window 174 becomes small and the amount of reflected light from the paper 200 becomes small. Is smaller than the reference value X1. On the other hand, as shown in FIG. 5C, if the position of the paper feed tray 110 is too high, the paper density in the sensor window 174 increases and the amount of reflected light from the paper 200 increases. , Larger than the reference value X1.

  For this reason, when the sensor value C1 is smaller than the reference value X1, the paper feed table elevating mechanism 120 is operated to raise the paper feed table 110 (S111). When the sensor value C1 is larger than the reference value X1, the paper feed table elevating mechanism 120 is operated to lower the paper feed table 110 (S112). When the sensor value C1 is equal to the reference value X1 (including the case where the sensor value C1 falls within the reference value range X1), the position of the paper feed table 110 is appropriate, and thus the paper feed platform lifting mechanism 120 is operated. First, the movement of the paper feed tray 110 is stopped (S113). As a result, the state of the floating sheet 200 can be properly maintained, and a sheet feeding operation that does not cause an empty feed or a double feed can be performed.

  The paper feed controller 160 repeats this process until the paper feed operation is completed (SS114). When the paper feeding operation is finished (S114: Yes), the air blowing operation by the floating air blowing mechanism 130 and the separation air blowing mechanism 140 is finished (S115).

  As described above, according to the air sheet feeder 100 of the present embodiment, the floating state of the sheet including the subsequent sheet is evaluated based on the sensor value C1 of the photoelectric sensor 171 and the elevation control of the sheet feeding table 110 is performed. Is doing.

  Since the sensor value C1 of the photoelectric sensor 171 indicates the amount of light input through the sensor window 174, it is not necessary to identify each sheet by a captured image or the like, and the floating state including the subsequent sheet is achieved with a simple configuration. Based on the paper feed table position control can be performed.

  The present invention is not limited to the above embodiment, and various modifications can be made. For example, a plurality of sensor windows and photoelectric sensors may be provided at different positions, and different sensor windows and photoelectric sensors may be used at the time of stopping the blowing and at the time of sending.

  Alternatively, the light emitting unit of the photoelectric sensor may be omitted, and reflected light from outside light or the like may be detected. In addition, during normal sheet feeding, the sheet feeding table 110 is not lowered, and therefore it may be determined whether the sheet feeding table 110 is raised or only the sheet feeding table 110 is stopped.

  A sheet feeding device according to a first aspect of the present invention includes a sheet feeding table that can be moved up and down, a blower mechanism that outputs air for floating a sheet placed on the sheet feeding table, and a side surface side of the sheet A sensor window that is fixedly attached to the sensor window, and a photoelectric sensor that detects the amount of reflected light and emits light toward the sensor window. And a paper feed control unit that controls the lifting and lowering operation of the paper feed table based on the detection result.

  In this aspect, the floating state of the paper including the subsequent paper is evaluated based on the detection result of the photoelectric sensor, and the raising / lowering control of the paper feed table is performed. Since the detection result of the photoelectric sensor indicates the amount of light input through the sensor window, it is not necessary to identify each sheet by a captured image or the like, and paper feeding based on the floating state including subsequent sheets with a simple configuration Stand position control can be performed.

  Here, the paper feed control unit can raise the paper feed table when the amount of light detected by the photoelectric sensor is smaller than the first reference value.

  When the amount of light detected by the photoelectric sensor is smaller than the first reference value, it indicates that the paper density in the sensor window is low. can do.

  The paper feed control unit can lower the paper feed table when the light amount detected by the photoelectric sensor is larger than the first reference value.

  When the amount of light detected by the photoelectric sensor is larger than the first reference value, it indicates that the paper density in the sensor window is high. can do.

  Further, the paper feed control unit can further control the raising / lowering operation of the paper feed table based on the detection result of the photoelectric sensor before the operation of the air blowing mechanism is started.

  Thereby, the uppermost sheet when the air blow is stopped can be set to an appropriate position.

  According to a second aspect of the present invention, there is provided a sheet feeding table lifting / lowering operation control method for an air sheet feeding apparatus that outputs a sheet feeding table that can be moved up and down, and air that floats a sheet placed on the sheet feeding table. A sheet state detection unit fixedly including a blower mechanism, a sensor window disposed on a side surface of the sheet, and a photoelectric sensor that emits light toward the sensor window and detects the amount of reflected light. A method of controlling the lifting / lowering operation of the sheet feeding table in the air sheet feeding device, wherein the lifting / lowering operation of the sheet feeding table is controlled based on the detection result of the photoelectric sensor when the blower mechanism is operated.

  In this aspect, the floating state of the paper including the subsequent paper is evaluated based on the detection result of the photoelectric sensor, and the raising / lowering control of the paper feed table is performed. Since the detection result of the photoelectric sensor indicates the amount of light input through the sensor window, it is not necessary to identify each sheet by a captured image or the like, and paper feeding based on the floating state including subsequent sheets with a simple configuration Stand position control can be performed.

DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus 12 ... Image forming part 100 ... Air paper feeder 110 ... Paper feed stand 120 ... Paper feed stand raising / lowering mechanism 130 ... Floating air blower mechanism 140 ... Separation air blower mechanism 150 ... Suction-type conveyance belt 152 ... Suction mechanism 160 ... paper feed control unit 170 ... paper state detection unit 171 ... photoelectric sensor 172 ... light emitting unit 173 ... light receiving unit 174 ... sensor window 200 ... paper

Claims (5)

A feed stand that can be raised and lowered;
A blower mechanism that outputs air for floating the paper placed on the paper feed table;
A paper state detection unit fixedly including a sensor window disposed on a side surface of the paper and a photoelectric sensor that emits light toward the sensor window and detects a reflected light amount;
A paper feed control unit that controls the raising and lowering operation of the paper feed table based on the detection result of the photoelectric sensor during the operation of the air blowing mechanism;
An air sheet feeding device comprising: The paper feed control unit
2. The air feeding device according to claim 1, wherein when the amount of light detected by the photoelectric sensor is smaller than a first reference value, the paper feeding base is raised. The paper feed control unit
The air feeding device according to claim 2, wherein when the light amount detected by the photoelectric sensor is larger than a first reference value, the paper feeding table is lowered. The paper feed control unit
The air according to any one of claims 1 to 3, further comprising: controlling the raising / lowering operation of the paper feed table based on a detection result of the photoelectric sensor before the operation of the blower mechanism is started. Paper feeder. A sheet feeding table that can be raised and lowered, a blower mechanism that outputs air for floating the sheet placed on the sheet feeding table, a sensor window disposed on a side surface of the sheet, and toward the sensor window A method for controlling the lifting operation of a sheet feeding base in an air sheet feeding device including a photoelectric sensor that emits light and detects a reflected light amount, and includes a sheet state detection unit that is fixedly mounted.
A method for controlling a lifting operation of a sheet feeding table in an air sheet feeding device, wherein the lifting / lowering operation of the sheet feeding table is controlled based on a detection result of the photoelectric sensor during the operation of the blower mechanism.