JP2021071653A - Image forming apparatus, control program, and air separation method - Google Patents

Abstract

To provide an image forming apparatus that can prevent reduction in separability of paper from a fixing member, while controlling glossiness of an image.SOLUTION: An image forming apparatus comprises: a fixing unit that, with a pressure member and a fixing member that is in contact with a toner image formed on a recording medium conveyed at a fixing nip formed through pressure contact of the pressure member, fixes the toner image to the recording medium at the fixing nip; a separation unit that separates the recording medium from the fixing member with blown-off air; and a control unit that causes a first member being one of the pressure member and the fixing member to function as a driving member that performs conveyance of the recording medium, and causes the other second member to function as an auxiliary driving member that performs a braking operation to increase an amount of micro-slip between the toner image and the fixing member at the fixing nip compared with that in a reference state, or an assisting operation to reduce the amount of micro-slip. The control unit changes at least any one of an air blowoff position and an air blowoff angle according to the operation that the second member is caused to perform.SELECTED DRAWING: Figure 5

Description

The present invention relates to an image forming apparatus, a control program, and an air separation method.

In the electrophotographic image forming apparatus, a toner image is formed on the paper, and the toner image on the paper is fixed by the fixing device provided in the image forming apparatus to form an image on the paper. The fixing device is, for example, a fixing nip formed by pressure-welding two fixing members such as a fixing roller to heat and pressurize the paper to convey the toner image to fix the toner image on the paper. ..

By the way, the toner of the toner image formed on the paper has adhesive strength by being heated when passing through the fixing nip. Therefore, the paper that has passed through the fixing nip may wrap around the surface of the fixing member that comes into contact with the toner image, causing jam. Therefore, there is known an air separation technique for separating paper from a fixing member by blowing air toward the paper discharging side of the fixing nip.

In this regard, the following patent documents disclose the following prior art. Air is blown to the separation point on the fixing belt, which changes according to the fixing pressure in the nip portion formed by pressing the pressure roller against the fixing roller via the fixing belt. In addition, the air blowing direction and the blowing position are controlled. As a result, even if the fixing pressure is changed according to the paper type or the like, air can be accurately blown to the separation point, and the paper can be accurately separated from the fixing belt.

Japanese Patent Application No. 2012-220773

On the other hand, in order to control the glossiness of the image on the paper, it is possible to control the drive of the fixing member so as to increase or decrease the amount of microslip between the toner image on the paper and the fixing member at the fixing nip. Toner. However, by controlling the drive of the fixing member, the shape of the fixing nip on the paper ejection side changes slightly. As a result, the air does not hit an appropriate spraying position to separate the paper from the fixing member, which may reduce the separability of the paper from the fixing member. The above prior art cannot address this issue.

The present invention has been made to solve such a problem. That is, it is an object of the present invention to provide an image forming apparatus capable of suppressing a decrease in the separability of paper from a fixing member while controlling the glossiness of an image.

The above object of the present invention is solved by the following means.

(1) An unfixed portion formed on the recording medium to be conveyed by a toner image forming portion for forming a toner image on a recording medium, a pressurizing member, and a fixing nip formed by being pressed against the pressurizing member. The fixing portion that fixes the toner image to the recording medium with the fixing nip by the fixing member that comes into contact with the toner image, and the recording medium on which the toner image is fixed by the blown air are fixed. By driving the separating portion separated from the member and the first member of either the pressurizing member or the fixing member at a predetermined constant speed, the recording medium can be made to function as a driving member for transporting the recording medium, and the other. The second member is either a braking operation that increases the amount of microslip between the toner image and the fixing member in the fixing nip from the reference state, or an assist operation that reduces the amount of microslip from the reference state. The control unit has a control unit that functions as an auxiliary drive member that performs one of the operations, and the control unit has the separation unit depending on whether the operation to be performed by the second member is the braking operation or the assist operation. An image forming apparatus that changes at least one of the air blowing position and the air blowing angle.

(2) The control unit controls the drive of the second member so that the drive torque of the first member increases from the reference state, thereby causing the second member to perform the braking operation, and the reference state. The image forming apparatus according to (1) above, wherein the second member is made to perform the assist operation by controlling the drive of the second member so that the drive torque of the first member is further reduced.

(3) The control unit controls the drive of the second member so as to reduce the surface speed of the second member with respect to the surface speed of the first member from the reference state, thereby causing the second member. By operating the braking operation and controlling the driving of the second member so as to increase the surface speed of the second member with respect to the surface speed of the first member from the reference state, the brake is applied to the second member. The image forming apparatus according to (1) above, which is operated.

(4) When the pressurizing member functions as the driving member, the fixing member functions as the auxiliary driving member, and the fixing member performs the braking operation, the control unit determines the position of the air blown out. The angle between the blowing angle of the air and the discharge direction of the recording medium from the fixing nip is made smaller than the reference state while making the discharge path of the recording medium from the fixing nip closer to the reference state. When the fixing member is made to perform the assist operation, the blowing position of the air is moved away from the reference state from the discharge path of the recording medium from the fixing nip, and the blowing angle of the air and the fixing are performed. The image forming apparatus according to any one of (1) to (3) above, wherein the angle formed by the discharge direction of the recording medium from the nip is larger than that of the reference state.

(5) When the pressurizing member functions as the driving member, the fixing member functions as the auxiliary driving member, and the fixing member performs the braking operation, the control unit determines the position of the air blown out. Without changing from the reference state, the angle formed by the blowing angle of the air and the paper ejection direction of the recording medium discharged from the fixing nip is made larger than the reference state, and the fixing member is subjected to the assist operation. The reference state is the angle between the blowout angle of the air and the paper ejection direction of the recording medium discharged from the fixing nip without changing the blowout position of the air from the reference state. The image forming apparatus according to any one of (1) to (3) above, which is made smaller.

(6) The control unit further controls the paper ejection side installation member arranged on the paper ejection side of the fixing nip, depending on whether the second member is to perform the braking operation or the assisting operation. The image forming apparatus according to any one of (1) to (5) above, which changes at least one of a position and an inclination angle.

(7) The control unit changes the air blowing position and the blowing angle based on the operation performed by the second member and the type of the recording medium, according to the above (1) to (6). The image forming apparatus according to any one.

(8) The control unit controls whether the second member is to perform the braking operation or the assisting operation in order to control the gloss of the image based on the toner image on the recording medium. The image forming apparatus according to any one of 1) to (7).

(9) The image forming apparatus according to any one of (1) to (8) above, wherein the fixing member is a belt.

(10) An unfixed portion formed on the recording medium to be conveyed by a toner image forming portion for forming a toner image on a recording medium, a pressurizing member, and a fixing nip formed by being pressed against the pressurizing member. The fixing portion that fixes the toner image to the recording medium with the fixing nip by the fixing member that comes into contact with the toner image, and the recording medium on which the toner image is fixed by the blown air are fixed. A control program for an image forming apparatus having a separation portion separated from a member, wherein the first member of either the pressurizing member or the fixing member is driven at a predetermined constant speed to drive the recording medium. The other second member is a braking operation that increases the amount of microslip between the toner image and the fixing member in the fixing nip from the reference state, or the amount of microslip. The procedure (a) for functioning as an auxiliary drive member that performs either one of the assist operations for reducing the amount from the reference state and the operation to be performed by the second member depend on whether the brake operation or the assist operation is performed. A control program for causing a computer to execute a process having a procedure (b) for changing at least one of the air blowing position and the air blowing angle of the separation unit.

(11) An unfixed portion formed on the recording medium to be conveyed by a toner image forming portion for forming a toner image on a recording medium, a pressurizing member, and a fixing nip formed by being pressed against the pressurizing member. The fixing portion that fixes the toner image to the recording medium with the fixing nip by the fixing member that comes into contact with the toner image, and the recording medium on which the toner image is fixed by the blown air are fixed. A method executed by an image forming apparatus having a separating portion separated from the members, wherein the first member of either the pressurizing member or the fixing member is driven at a predetermined constant speed. A braking operation in which the other second member functions as a driving member for transporting a recording medium and increases the amount of microslip between the toner image and the fixing member in the fixing nip from a reference state, or the micro Whether the step (a) of functioning as an auxiliary drive member that performs one of the assist operations of reducing the slip amount from the reference state and the operation of the second member are the brake operation or the assist operation. An air separation method comprising a step (b) of changing at least one of the air blowing position and the air blowing angle of the separating portion according to the above.

Of the fixing members, one member functions as a driving member for transporting paper, and the other member is a braking operation that increases or decreases the amount of microslip between the fixing member and the toner image from the reference state. It functions as an auxiliary drive member that performs either of the above. Then, at least one of the air blowing position and the blowing angle for separating the paper from the fixing member is changed depending on whether the other member is to perform the braking operation or the assisting operation. As a result, it is possible to suppress a decrease in the separability of the paper from the fixing member while controlling the glossiness of the image.

It is the schematic which shows the structure of the image forming apparatus. It is a block diagram which shows the structure of an image forming apparatus. It is a figure which shows the simplified structure of the fixing part. It is a figure which shows the simplified structure of the roller drive mechanism for rotating a fixing roller and a pressure roller. It is a figure which shows the simplified structure of the separation part. It is explanatory drawing which shows the inclination angle of the paper ejection guide which is changed according to whether the fixing roller is made to brake operation or assist operation. It is explanatory drawing which shows the position of the lower separation claw which is changed according to whether the fixing roller is made to brake operation or assist operation. It is a flowchart which shows the operation of an image forming apparatus. It is a figure which shows the simplified structure of the separation part. It is a figure which shows the simplified structure of the duct of a separation part. It is a figure which compares and shows the change of the shape of the paper discharge side of the fixing nip between the case where the fixing roller is made to brake and assist the operation, and the case where the pressurizing roller is made to perform the braking operation and the assist operation.

Hereinafter, the image forming apparatus according to the embodiment of the present invention will be described with reference to the drawings. In the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios. In the present specification, the angle formed by two directions or faces or the like means the smaller angle of the angles formed by the two directions or faces or the like.

(First Embodiment)
FIG. 1 is a schematic view showing the configuration of the image forming apparatus 100. FIG. 2 is a block diagram showing the configuration of the image forming apparatus 100.

The image forming apparatus 100 includes a control unit 110, a storage unit 120, a communication unit 130, an operation display unit 140, an image reading unit 150, an image control unit 160, and an image forming unit 170. These components are communicatively connected to each other by bus 180. The image forming apparatus 100 may be configured by an MFP (Multifunction Peripheral).

The control unit 110 includes a CPU (Central Processing Unit) and various memories, and controls each of the above units and performs various arithmetic processes according to a program. The details of the operation of the control unit 110 will be described later.

The storage unit 120 is composed of an SDD (Solid State Drive), an HDD (Hard Disk Drive), or the like, and stores various programs and various data.

The communication unit 130 is an interface for communicating between the image forming apparatus 100 and the external device. As the communication unit 130, a network interface based on standards such as Ethernet (registered trademark), SATA, and IEEE 1394 is used. Further, as the communication unit 130, various local connection interfaces such as a wireless communication interface such as Bluetooth (registered trademark) and IEEE802.11 are used.

The operation display unit 140 includes a touch panel, a numeric keypad, a start button, a stop button, and the like, and is used for displaying various information and inputting various instructions.

The image reading unit 150 includes a light source such as a fluorescent lamp and an image sensor such as a CCD (Charge Coupled Device) image sensor. The image reading unit 150 irradiates a document set at a predetermined reading position with light from a light source, photoelectrically converts the reflected light with an image sensor, and generates image data from the electric signal.

The image control unit 160 performs layout processing and rasterization processing of print data included in a print job or the like received by the communication unit 130 to generate image data in a bitmap format.

The print job is a general term for print commands to the image forming apparatus 100, and includes print data and print settings. The print data is data of a document to be printed, and the print data may include various data such as image data, vector data, and text data. Specifically, the print data may be PDL (Page Description Language) data, PDF (Portable Document Form) data, or TIFF (Tagged Image File Form) data. The print setting is a setting related to image formation on the paper 900, and includes, for example, various settings such as the number of pages, the number of copies to be printed, the paper type, the selection of color or monochrome, and the page allocation. The print settings may further include settings that increase or decrease gloss.

The image forming unit 170 includes an image forming unit 40, a fixing unit 50, a paper feeding unit 60, and a paper conveying unit 70.

The image forming unit 40 has image forming units 41Y, 41M, 41C, and 41K corresponding to toners of each color of Y (yellow), M (magenta), C (cyan), and K (black). Each image forming unit 41Y, 41M, 41C, 41K forms a toner image on the photoconductor drum through the processes of charging, exposure, and development based on the image data. The exposure is performed by scanning the photoconductor drum with a laser beam. The toner image formed on the photoconductor drum is sequentially superposed on the intermediate transfer belt 42 and transferred onto the paper 900 by the secondary transfer roller 43.

The fixing portion 50 includes a fixing roller 51a and a pressure roller 52, and when the fixing roller 51a and the pressure roller 52 are pressed against each other, a fixing nip N (FIG. 5) is provided between the fixing roller 51a and the pressure roller 52. 3) is formed. The fixing roller 51a constitutes a fixing member that comes into contact with the unfixed toner image T formed on the paper 900 at the fixing nip N. The pressurizing roller 52 constitutes a pressurizing member. In the fixing nip N, the fixing roller 51a and the pressure roller 52 arranged on the inner peripheral surface of the fixing belt 51b are pressed against each other via the fixing belt 51b by using the fixing belt 51b (see B in FIG. 3). As a result, it may be formed between the fixing belt 51b and the pressure roller 52. In this case, the fixing belt 51b constitutes the fixing member.

FIG. 3 is a diagram showing a simplified configuration of the fixing portion 50.

FIG. 3A is a configuration of a fixing portion 50 including a fixing roller 51a and a pressure roller 52. In this example, the toner image T is fixed to the paper by heating and pressurizing the toner image T with the fixing nip N formed by pressing the fixing roller 51a and the pressure roller 52 against each other. The fixing roller 51a is, for example, a core metal formed of a metal such as iron coated with an elastic layer. As the elastic layer, for example, heat-resistant silicone rubber can be used. The elastic layer may have a structure in which heat-resistant silicone rubber is coated with PTFE (polytetrafluoroethylene), which is a heat-resistant resin. The fixing roller 51a includes a heating source such as a halogen heater inside. The pressure roller 52 is, for example, a PI (polyimide) base material whose outer peripheral surface is coated with an elastic layer. As the elastic layer, for example, heat-resistant silicone rubber can be used. The elastic layer may have a structure in which heat-resistant silicone rubber is coated with a PFA (perfluoroalkoxy) tube as a surface release layer.

FIG. 3B is a configuration of a fixing portion 50 including a fixing roller 51a, a fixing belt 51b, and a pressure roller 52. In this example, the fixing roller 51a and the pressure roller 52 are pressed against each other via the fixing belt 51b to form a fixing nip N between the fixing belt 51b and the pressure roller 52. The fixing belt 51b may have a configuration in which the outer peripheral surface of the base material of PI is coated with heat-resistant silicone rubber as an elastic layer, and further coated with a tube of PFA which is a heat-resistant resin.

Hereinafter, for the sake of simplicity, the case where the fixing belt 51b is not used (the case of the configuration of A in FIG. 3) will be described as an example. Further, it is assumed that the surface of the paper 900 on which the toner image T is formed faces the fixing roller 51a side, so that the paper 900 is conveyed while the toner image T is in contact with the fixing roller 51a at the fixing nip N. To do.

FIG. 4 is a diagram showing a simplified configuration of a roller drive mechanism 55 for rotating the fixing roller 51a and the pressure roller 52.

The fixing roller 51a is connected to the first motor 515 as a drive source. Specifically, the gear 512 provided on the rotating shaft of the fixing roller 51a meshes with the intermediate gear 513, and the intermediate gear 513 meshes with the gear 514 provided on the rotating shaft of the first motor 515. As a result, the torque of the first motor 515 is transmitted to the fixing roller 51a.

The pressurizing roller 52 is connected to a second motor 525 as a drive source. Specifically, the gear 522 provided on the rotating shaft of the pressurizing roller 52 meshes with the intermediate gear 523, and the intermediate gear 523 meshes with the gear 524 provided on the rotating shaft of the second motor 525. As a result, the torque of the second motor 525 is transmitted to the pressurizing roller 52.

The rotation of the fixing roller 51a and the pressure roller 52 is controlled by the torque transmitted from the first motor 515 and the second motor 525, respectively.

According to the above-described configuration, the fixing unit 50 heats and pressurizes the paper 900 conveyed to the fixing nip N by the fixing nip N, and rotates the fixing roller 51a and the pressure roller 52 to rotate the toner on the paper 900. The image is melt-fixed (hereinafter, simply referred to as "fixing") on the surface of the paper 900.

As will be described later, the fixing roller 50 is set in a reference state in which gloss control is not performed to increase the gloss of the image formed on the paper 900, or in order to perform gloss control, based on the print settings of the print job. The toner image is fixed on the paper 900 in a state where the 51a is braked or assisted.

The fixing portion 50 includes a separating portion 53 that separates the paper 900 stuck to the fixing roller 51a due to the adhesive force of the toner image melted at the time of fixing by blowing air toward the downstream side of the fixing nip N.

FIG. 5 is a diagram showing a simplified configuration of the separation unit 53.

The separation unit 53 includes an air blowing mechanism 531. The separation unit 53 may further include, for example, an induction member 532 and a cam 533. The air blowing mechanism 531 includes a sirocco fan 531a, a duct 531b, and a protrusion 531c provided on the outer peripheral surface of the duct 531b. The air blown out from the sirocco fan 531a is guided through the inside of the duct 531b to a predetermined air blowing position (hereinafter, simply referred to as “blowing position”). As a result, air is blown out from the blowing position in a predetermined blowing direction (hereinafter, simply referred to as "blowing direction"). The blowing direction is a direction on a plane parallel to the discharge direction 73a of the paper 900 from the fixing nip N, and corresponds to the blowing angle of air.

The air blowing mechanism 531 moves along the rail by engaging the protrusion 531c with the rail having a constant curvature of the guiding member 532 fixed to the housing of the image forming apparatus 100. In the air blowing mechanism 531, the protrusion 531c receives a force in the vertical direction by a cam 533 that is rotated by a driving force of a motor (not shown) about the rotation shaft 532a, so that the protrusion 531c is placed in any of a plurality of predetermined positions. Move to. There are, for example, three predetermined positions, which are indicated by a solid line, a thick broken line, and a thin broken line in FIG. 5, respectively. By moving the air blowing mechanism 531 to each predetermined position, the blowing position and the blowing direction can be changed. The predetermined position is not limited to the above-mentioned three positions.

The roller drive mechanism 55 causes either one of the fixing roller 51a and the pressurizing roller 52 to function as a member (hereinafter, referred to as “driving member”) for transporting the paper 900. Specifically, the drive member is a member that drives the transfer of the paper 900 so that the transfer speed of the paper 900 at the fixing nip N matches the reference speed (so-called process speed) used by the image forming unit 170. For example, in the reference state, the fixing roller 51a as an auxiliary drive member driven by the first motor 515 rotates in accordance with the rotation of the pressurizing roller 52 as a drive member driven by the second motor 525. At this time, the pressure roller 52 functions as a driving member. When the fixing roller 51a is rotated in accordance with the rotation of the pressurizing roller 52, the first motor 515 that transmits torque to the fixing roller 51a may be turned off. In the reference state, the surface velocities of the fixing roller 51a and the pressure roller 52 are equalized. Therefore, in the reference state, torque may be transmitted to the fixing roller 51a by the first motor 515 to rotate at the same peripheral speed as the pressurizing roller 52 functioning as a driving member.

In the above, of the fixing roller 51a and the pressure roller 52, one roller (first roller) that causes the pressure roller 52 to function as a drive member, and the other roller (second roller) that causes the fixing roller 51a to function as an auxiliary drive member. Roller). However, as in the third embodiment described later, the first and second rollers may be reversed. That is, the first roller (driving member) may be the fixing roller 51, and the second roller (auxiliary driving member) may be the pressurizing roller 52. The auxiliary drive member is either a braking operation that increases the amount of microslip between the toner image T and the fixing roller 51a in the fixing nip N from the reference state, or an assisting operation that reduces the microslip amount from the reference state. It is a member capable of one operation. The microslip amount can be indirectly measured as, for example, the amount of movement of the auxiliary drive member with respect to the drive member per unit time in the fixing nip N. The amount of movement of the auxiliary drive member with respect to the drive member per unit time can be calculated, for example, based on the difference between the surface speed of the auxiliary drive member and the surface speed of the drive member.

Hereinafter, for the sake of simplicity, the pressurizing roller 52 will function as a driving member, and the fixing roller 51a will function as an auxiliary driving member.

By causing the fixing roller 51a to perform a braking operation or an assisting operation as an auxiliary driving member, the gloss of the image on the paper 900 can be controlled. For example, by causing the fixing roller 51a to brake, the gloss of the image on the paper 900 can be increased. Further, by causing the fixing roller 51a to perform an assist operation, the gloss of the image on the paper 900 can be reduced.

In FIG. 5, 51a (N) shows the shape of the fixing roller 51a in the reference state on the paper 900 discharge side of the fixing nip N. 51a (B) shows the shape of the fixing roller 51a on the paper 900 discharge side of the fixing nip N when the fixing roller 51a is braked. 51a (A) shows the shape of the fixing roller 51a on the paper 900 ejection side of the fixing nip N when the fixing roller 51a is assisted. By causing the fixing roller 51a to perform a braking operation or an assisting operation in this way, the shape of the fixing nip N on the paper 900 discharge side is slightly changed as compared with the reference state.

In FIG. 5, the position of the air blowing mechanism 531 shown by the solid line indicates the position of the air blowing mechanism 531 in the reference state. The position of the air blowing mechanism 531 shown by the thick broken line indicates the position of the air blowing mechanism 531 when the fixing roller 51a is made to brake. The position of the air blowing mechanism 531 shown by a thin broken line indicates the position of the air blowing mechanism 531 when the fixing roller 51a is made to perform an assist operation. By moving the air blowing mechanism 531 to such a position, the blowing position and the blowing direction are changed from the reference state depending on whether the fixing roller 51a is braked or assisted. That is, the air blowing position and the blowing angle of the air blowing mechanism 531 are changed from the reference state depending on whether the fixing roller 51a is braked or assisted. The blowing position and blowing direction of the fixing roller 51a during the braking operation and the assisting operation correspond to the above-mentioned change in the shape of the fixing nip N on the paper 900 ejection side, and the paper 900 can be separated from the fixing roller 51a. The best position and direction can be determined experimentally.

The blowout position and blowout direction changed from the reference state are changed according to the degree of braking operation (value of microslip amount) and the degree of assist operation (value of microslip amount) performed on the fixing roller 51a. May be good. That is, for example, even when the fixing roller 51a is made to perform the braking operation, the blowing position and the blowing direction may be changed depending on whether the degree of the braking operation is relatively large or relatively small.

When the fixing roller 51a is braked, the air blowing mechanism 531 is moved to the position of the air blowing mechanism 531 shown by the thick broken line in FIG. As a result, the ejection position approaches the discharge path 73 of the paper 900 from the fixing nip N closer than the reference state, and the angle formed by the ejection direction and the discharge direction 73a of the paper 900 from the fixing nip N is closer to the reference state. It becomes smaller. When the fixing roller 51a is assisted, the air blowing mechanism 531 is moved to the position of the air blowing mechanism 531 shown by a thin broken line in FIG. As a result, the blowout position is moved away from the reference state from the paper 900 discharge path 73 from the fixing nip N, and the angle formed by the blowout direction and the paper 900 discharge direction 73a from the fixing nip N is greater than the reference state. growing.

The paper 900 on which the toner image is fixed by the fixing portion 50 is discharged to the output tray 90 as printed matter.

The paper feed unit 60 has a plurality of paper feed trays 61 and 62, and feeds the paper 900 stored in the paper feed trays 61 and 62 one by one to the transport path on the downstream side.

The paper transport unit 70 has a plurality of transport rollers for transporting the paper 900, and transports the paper 900 between the image forming unit 40, the fixing unit 50, and the paper feeding unit 60. The plurality of transport rollers include a resist roller 71 for correcting the inclination of the paper 900 and a loop roller 72 for forming a predetermined amount of loops on the paper 900.

The paper transport unit 70 discharges the image-formed paper 900 to the output tray 90.

The operation of the control unit 110 will be described.

When fixing the toner image T on the paper 900 in the reference state based on the print settings included in the print job, the control unit 110 drives the fixing roller 51a to rotate the pressure roller 52. To control. When the control unit 110 controls the gloss by causing the fixing roller 51a to brake based on the print setting, the control unit 110 increases the amount of microslip between the toner image T and the fixing roller 51a in the fixing nip N from the reference state. Controls the roller drive mechanism 55. When the control unit 110 controls the gloss by causing the fixing roller 51a to perform an assist operation based on the print setting, the control unit 110 reduces the amount of microslip between the toner image T and the fixing roller 51a in the fixing nip N from the reference state. Controls the roller drive mechanism 55.

The control unit 110 can cause the fixing roller 51a to brake by controlling the driving of the fixing roller 51a so that the driving torque of the pressurizing roller 52 increases from the reference state by the roller driving mechanism 55. The control unit 110 can cause the fixing roller 51a to perform an assist operation by controlling the driving of the fixing roller 51a so that the driving torque of the pressurizing roller 52 is reduced from the reference state by the roller driving mechanism 55. For example, the driving torque of the pressurizing roller 52 in a state where the fixing roller 51a is driven to rotate by driving the pressurizing roller 52 in the reference state is set as the reference (1). Then, by controlling the drive of the fixing roller 51a so that the driving torque of the pressurizing roller 52 becomes 1.5 times the reference, the fixing roller 51a can be braked. Further, by controlling the drive of the fixing roller 51a so that the driving torque of the pressurizing roller 52 becomes 0.5 times the reference, the fixing roller 51a can be assisted.

On the other hand, the control unit 110 controls the roller drive mechanism 55 so as to reduce the surface speed of the fixing roller 51a with respect to the surface speed of the pressurizing roller 52 from the reference state, so that the fixing roller 51a may be braked. Good. The control unit 110 may cause the fixing roller 51a to perform an assist operation by controlling the roller drive mechanism 55 so as to increase the surface speed of the fixing roller 51a with respect to the surface speed of the pressure roller 52 from the reference state. For the surface layer velocity, for example, a ladder pattern is formed at the end of the surface of the fixing roller 51a, and the reflectance of the light emitted from the fixed light source toward the ladder pattern is measured by using an optical sensor adjacent to the light source. It can be detected by measuring the period in which the reflectance increases or decreases.

In the reference state, the control unit 110 sets the position of the air blowing mechanism 531 to the position shown by the solid line in FIG. When the fixing roller 51a is braked, the control unit 110 brings the blowing position closer to the transport path of the paper 900 from the fixing nip than the reference state, and the blowing direction and the discharging direction of the paper 900 from the fixing nip N are set. Make the angle to be smaller than the reference state. That is, when the fixing roller 51a is braked, the control unit 110 moves the position of the air blowing mechanism 531 to the position indicated by the thick broken line in FIG. When the fixing roller 51a is assisted, the control unit 110 moves the blowing position away from the reference state to the transport path of the paper 900 from the fixing nip, and the blowing direction and the discharging direction of the paper 900 from the fixing nip N are set. Make the angle to be made larger than the reference state. That is, when the fixing roller 51a is braked, the control unit 110 moves the position of the air blowing mechanism 531 to the position indicated by the thin broken line in FIG. As a result, depending on whether the fixing roller is braked or assisted, the paper 900 is directed to an appropriate spraying position around the discharge side end of the paper 900 of the fixing nip N to separate the paper 900 from the fixing roller 51a. The air can be blown at an appropriate angle.

The control unit 110 sets at least one of the position and the inclination angle of the paper discharge side installation member arranged on the paper discharge side of the fixing nip N, depending on whether the fixing roller 51a is braked or assisted. Let me change it.

FIG. 6 is an explanatory view showing an inclination angle of the paper ejection guide 74 that is changed depending on whether the fixing roller 51a is braked or assisted. FIG. 7 is an explanatory view showing the position of the lower separation claw 75 that is changed depending on whether the fixing roller 51a is braked or assisted. The paper ejection guide 74 and the lower separation claw 75 are included in the paper ejection side installation member. The paper discharge guide 74 and the lower separation claw 75 shown by the solid lines in FIGS. 6 and 7 indicate the paper discharge guide 74 and the lower separation claw 75 in the reference state, respectively. The paper ejection guide 74 and the lower separation claw 75 shown by the thick broken line indicate the paper ejection guide 74 and the lower separation claw 75 when the fixing roller 51a is braked, respectively. The paper ejection guide 74 and the lower separation claw 75 shown by a thin broken line indicate the paper ejection guide 74 and the lower separation claw 75 when the fixing roller 51a is assisted, respectively. The paper ejection guide 74 and the lower separation claw 75 may be used together.

As shown in FIG. 6, when the fixing roller 51a is braked, the inclination angle of the paper discharge guide 74 for guiding the transfer of the paper 900 discharged from the fixing nip N with respect to the horizontal plane is set. By lowering the position in the vertical direction of the downstream end of the paper ejection guide 74 with respect to the transport direction, the size is made larger than the reference state. When the fixing roller 51a is assisted, the tilt angle of the paper ejection guide 74 with respect to the horizontal plane is increased in the vertical direction of the downstream end of the paper ejection guide 74 with respect to the transport direction of the paper 900, so that the tilt angle is larger than the reference state. To do. When the fixing roller 51a is braked, the air blowing mechanism 531 is moved vertically downward as described above. On the other hand, when the fixing roller 51a is braked, the paper 900 is ejected slightly downward from the reference state. Therefore, the space for transporting the paper 900 discharged from the fixing nip N may be too small. Therefore, when the fixing roller 51a is braked, the tilt angle of the paper ejection guide 74 with respect to the horizontal plane is lowered in the vertical direction of the downstream end of the paper ejection guide 74 with respect to the transport direction of the paper 900, so that the reference state is obtained. Make it bigger. When the fixing roller 51a is to be assisted, the air blowing mechanism 531 is moved vertically upward. On the other hand, when the fixing roller 51a is made to perform an assist operation, the paper 900 is ejected slightly upward from the reference state. Therefore, the space for transporting the paper 900 discharged from the fixing nip N may become excessive. Therefore, when the fixing roller 51a is assisted, the tilt angle of the paper ejection guide 74 with respect to the horizontal plane is raised in the vertical direction of the downstream end of the paper ejection guide 74 with respect to the transport direction of the paper 900, so that the reference state is obtained. Make it bigger. In this way, the paper 900 discharged from the fixing nip N is conveyed by changing the inclination angle of the paper ejection guide 74 with respect to the horizontal plane according to whether the fixing roller 51a is braked or assisted. The space to be created can be made to an appropriate size. As a result, the function of the paper ejection guide 74 can be ensured, and the transportability of the paper 900 can be stabilized.

As shown in FIG. 7, when the fixing roller 51a is braked, the paper 900 discharged from the fixing nip N is prevented from being caught in the pressure roller 52 in the vertical direction of the lower separation claw 75. Lower the position from the reference state. As described above, when the fixing roller 51a is braked, the paper 900 is ejected slightly downward from the reference state. Therefore, the distance between the paper 900 discharged from the fixing nip N and the lower separation claw 75 may be too small. When the fixing roller 51a is to be assisted, the vertical position of the lower separation claw 75 is raised from the reference state. As described above, when the fixing roller 51a is assisted, the paper 900 is ejected slightly upward from the reference state. Therefore, the distance between the paper 900 discharged from the fixing nip N and the lower separation claw 75 may become excessive. By changing the position of the lower separation claw according to whether the fixing roller 51a is braked or assisted, the distance between the paper 900 discharged from the fixing nip N and the lower separating claw 75 is appropriate. Can be kept at intervals. As a result, the function of the lower separation claw 75 can be ensured, and the transportability of the paper 900 can be stabilized.

The control unit 110 can change the blowout position and the blowout direction (blowout angle) based on the operations such as the braking operation and the assist operation performed by the fixing roller 51a and the type of the paper 900 set in the print setting. For example, when the fixing roller 51a is to be braked or assisted in order to control the gloss, when the paper 900 is fixed on a paper 900 having a small basis weight, the separability of the paper 900 from the fixing roller 51a is relatively poor. The blowing position and blowing direction are changed according to each operation. On the other hand, even when the fixing roller 51a is braked or assisted in order to control the gloss, the paper 900 can be fixed to the paper 900 having a relatively good basis weight and having a relatively good separability from the fixing roller 51a. If so, the blowout position and blowout direction may not be changed.

The operation of the image forming apparatus 100 will be described.

FIG. 8 is a flowchart showing the operation of the image forming apparatus 100. This flowchart can be executed by the control unit 110 according to the program stored in the storage unit 120.

The control unit 110 determines whether or not the print job has been acquired (S101). The control unit 110 may determine that the print job has been acquired, for example, because the print job has been received by the communication unit 130.

The control unit 110 generates image data by rasterizing the print data of the print job, and forms the toner image T on the paper 900 based on the generated image data and print settings (S102).

The control unit 110 determines whether or not to perform gloss control in the fixing by the fixing unit 50 based on the print settings included in the print job (S103). The control unit 110 determines that the gloss control is performed when the print setting is set to increase the gloss or decrease the gloss.

When the control unit 110 determines that gloss control is not performed (S103: NO), the toner image T is fixed on the paper 900 in the reference state, and the default position corresponding to the reference state (shown by a solid line in FIG. 5). The paper 900 is separated from the fixing roller 51a by blowing air at a predetermined timing from the air blowing mechanism 531 arranged at the position) (S109).

When the control unit 110 determines that the gloss control is performed (S103: YES), the control unit 110 determines whether to increase the gloss based on the print setting (S104). The control unit 110 determines that the gloss is increased when the print setting is set to increase the gloss.

When the control unit 110 determines that the gloss is increased (S104: YES), the control unit 110 changes the arrangement of the air blowing mechanism 531 so that the blowing position and the blowing direction correspond to the case where the fixing roller 51a is braked. (S105). Then, the control unit 110 causes the fixing roller 51a to brake to fix the toner image T on the paper 900, and blows air from the air blowing mechanism 531 to fix the toner image T on the paper 900 after fixing. It is separated from the fixing roller 51a (S106).

When the control unit 110 determines that the gloss is not increased (S104: NO), the control unit 110 changes the arrangement of the air blowing mechanism 531 so that the blowing position and the blowing direction correspond to the case where the fixing roller 51a is assisted. (S107). Then, the control unit 110 causes the fixing roller 51a to perform an assist operation to fix the toner image T on the paper 900, and blows air from the air blowing mechanism 531 to blow out the paper 900 after the toner image T is fixed. It is separated from the fixing roller 51a (S108).

The control unit 110 ejects the paper 900 after the toner image T has been fixed (S110).

(Example)
The separability of the paper 900 by air blowing was measured when the blowing position and the blowing direction were changed corresponding to the case where the fixing roller 51a was braked and the case where the assisting operation was performed.

1. 1. Measurement conditions Fixing roller: outer diameter φ70, rubber thickness 20 mm
Pressurized roller: outer diameter φ70, rubber thickness 3 mm
Fixing belt: outer diameter φ120, substrate PI (70 μm thickness), rubber layer (220 μm thickness), surface layer PFA tube (30 μm thickness)
Fixing nip width: 23 mm
Paper transport speed: Approximately 460 mm / s
2. Measurement and Evaluation Method (1) A toner image T of a solid image of magenta: 100% and cyan: 100% is formed on the entire surface of the paper. Further, a toner image T of a solid image of magenta: 100% and cyan: 100% is formed on the paper by changing the margin width for each paper so as to have a band-shaped margin at the tip of the paper, and the margin width is stepped. To increase.

(2) Evaluate the separability of paper from the fixing belt by changing the blowing position and blowing direction correspondingly when the fixing belt is braked and when the fixing belt is operated to assist. did. When the tip of the duct 531b of the air blowing mechanism 531 shown in FIG. 5 is braked by the fixing belt, the blowing position and the blowing direction are 3 in the direction approaching the discharge path 73 from the default position corresponding to the reference state. Changed by rotating °. When the fixing belt is to be assisted, the blowing position and the blowing direction are changed by rotating the tip of the duct 531b by 3 ° from the default position corresponding to the reference state in the direction away from the discharge path 73. The paper separability was evaluated by measuring the minimum margin width at which the paper from the fixing belt was separated by air blowing from the paper on which the toner image T was formed in (1) above.

(3) As a comparative example, the above (1) and (2) were performed with the blowing position and the blowing direction left as they were in the reference state.

3. 3. Results (1) When the fixing belt was braked, the minimum margin width for separating the paper from the fixing belt was 3 mm in the comparative example, whereas it was 1 mm in the example.

(2) When the fixing belt was assisted, in the comparative example, the minimum margin width at which the paper was separated from the fixing belt was 4 mm, whereas in the example, it was 2 mm.

(3) From the above (1) and (2), it was demonstrated that high separability can be realized by the examples.

(Second Embodiment)
A second embodiment of the present invention will be described. The differences between the present embodiment and the first embodiment are as follows. In the first embodiment, the blowing position and the blowing direction are changed depending on whether the fixing roller is braked or assisted. on the other hand. In the present embodiment, the blowing direction is changed without changing the blowing position depending on whether the fixing roller is braked or assisted. That is, the blowing position is fixed and the angle formed by the blowing direction and the discharging direction 73a of the paper discharged from the fixing nip N is changed according to whether the fixing roller is braked or assisted. Since the present embodiment is the same as that of the first embodiment in other respects, redundant description will be omitted or simplified.

FIG. 9 is a diagram showing a simplified configuration of the separation unit 53. FIG. 10 is a diagram showing a simplified configuration of the duct 531b of the separation unit 53.

In FIG. 9, the thick alternate long and short dash line indicates the path of air blown from the air blowing mechanism 531 when the fixing roller 51a is braked. The thin alternate long and short dash line indicates the path of air blown from the air blowing mechanism 531 when the fixing roller 51a is assisted. The alternate long and short dash line with an intermediate thickness indicates the path of air blown from the air blowing mechanism 531 in the reference state. In this way, when the fixing roller 51a is braked, the angle formed by the blowing direction and the discharging direction 73a of the paper 900 discharged from the fixing nip N is set from the reference state without changing the blowing position from the reference state. Enlarge. Further, when the fixing roller 51a is to perform the assist operation, the angle formed by the blowing direction and the discharging direction 73a of the paper 900 discharged from the fixing nip N is made smaller than the reference state without changing the blowing position from the reference state. .. As a result, depending on whether the fixing roller is braked or assisted, the paper 900 is directed to an appropriate spraying position around the discharge side end of the paper 900 of the fixing nip N to separate the paper 900 from the fixing roller 51a. The air can be blown at an appropriate angle.

As shown in FIG. 10, the duct 531b of the separation unit 53 includes the ventilation angle control plate 531d. By changing the inclination angle of the blower angle control plate 531d, the blowout direction can be changed without changing the blowout position. That is, the angle formed by the blowing direction and the discharging direction 73a of the paper 900 discharged from the fixing nip N can be changed without changing the blowing position. For the inclination angle of the blower angle control plate 531d, for example, the side of the blower angle control plate 531d near the air blowing position of the duct 531b is fixed to the duct 531b, and the side far from the blowing position is cam (FIG. It can be changed by lifting it vertically upward using (not shown).

(Third Embodiment)
A third embodiment of the present invention will be described. The differences between the present embodiment and the first embodiment are as follows. In the first embodiment, the pressurizing roller 52 functions as a driving member, and the fixing roller 51a functions as an auxiliary driving member. On the other hand, in the present embodiment, the fixing roller 51a is made to function as an auxiliary driving member, and the pressurizing roller 52 is made to function as an auxiliary driving member. Since the present embodiment is the same as that of the first embodiment in other respects, redundant description will be omitted or simplified.

FIG. 11 compares the change in the shape of the fixing nip N on the paper 900 discharge side between the case where the fixing roller 51a is subjected to the braking operation and the assist operation and the case where the pressure roller 52 is subjected to the braking operation and the assist operation. It is a figure which shows. Similar to FIG. 5, 51a (N) shows the shape of the fixing roller 51a in the reference state on the paper 900 discharge side of the fixing nip N. 51a (B) shows the shape of the fixing roller 51a on the paper 900 discharge side of the fixing nip N when the fixing roller 51a is braked. 51a (A) shows the shape of the fixing roller 51a on the paper 900 ejection side of the fixing nip N when the fixing roller 51a is assisted.

FIG. 11A shows a change in the shape of the fixing nip N on the paper 900 discharge side when the fixing roller 51a is subjected to each of a braking operation and an assist operation as an auxiliary driving member. FIG. 11B shows a change in the shape of the fixing nip N on the paper 900 discharge side when the pressurizing roller 52 is subjected to each of a braking operation and an assisting operation as an auxiliary driving member.

Comparing A and B in FIG. 11, the paper 900 of the fixing nip N with respect to the reference state is obtained when the fixing roller 51a is braked and assisted and when the pressurizing roller 52 is braked and assisted. The change in shape on the discharge side is reversed.

Therefore, when the fixing roller 51a is braked and assisted, and when the pressurizing roller 52 is braked and assisted, the blowout position and blowout direction are set with respect to the blowout position and blowout direction in the reference state. Reverse the direction of change. That is, when the fixing roller 51a is braked and assisted, as described in the first embodiment, when the fixing roller 51a is braked, the blowing position is set to the transport path of the paper 900 from the fixing nip. In addition, the angle between the blowout direction and the discharge direction of the paper 900 from the fixing nip N is made smaller than the reference state. When the fixing roller 51a is to be assisted, the blowing position is set away from the reference state in the transport path of the paper 900 from the fixing nip, and the angle between the blowing direction and the discharge direction of the paper 900 from the fixing nip N is set. Make it larger than the standard state. On the other hand, when the pressure roller 52 is braked as in the present embodiment, the blowing position is moved away from the reference state from the transport path of the paper 900 from the fixing nip, and the blowing direction and the fixing nip N are used. The angle formed by the ejection direction of the paper 900 is made larger than the reference state. When the pressure roller 52 is to be assisted, the blowing position is brought closer to the transport path of the paper 900 from the fixing nip than the reference state, and the angle between the blowing direction and the discharging direction of the paper 900 from the fixing nip N is set. , Make it smaller than the standard state. As a result, regardless of which of the fixing roller 51a and the pressure roller 52 functions as the auxiliary drive member, the discharge side of the paper 900 of the fixing nip N depends on whether the brake operation or the assist operation is performed as the auxiliary drive member. Air can be blown to an appropriate blowing position around the edge at an appropriate blowing position and blowing angle.

The embodiment of the present invention has the following effects.

Of the fixing members, one first member functions as a driving member for transporting paper, and the other second member is a braking operation that increases the amount of microslip between the fixing member and the toner image from the reference state, or It functions as an auxiliary drive member that performs one of the assist operations to be reduced. Then, at least one of the air blowing position and the blowing angle for separating the paper from the fixing member is changed depending on whether the second member is to perform the braking operation or the assist operation. As a result, it is possible to suppress a decrease in the separability of the paper from the fixing member while controlling the glossiness of the image.

Further, by controlling the drive of the second member so that the drive torque of the first member increases from the reference state, the second member is made to brake. Then, by controlling the drive of the second member so that the drive torque of the first member is reduced from the reference state, the second member is made to perform an assist operation. As a result, the second member can easily function as an auxiliary drive member.

Further, by controlling the drive of the second member so as to reduce the surface speed of the second member with respect to the surface speed of the first member from the reference state, the second member is made to brake. Then, by controlling the drive of the second member so as to increase the surface speed of the second member with respect to the surface speed of the first member from the reference state, the second member is made to perform the braking operation. As a result, the second member can easily function as an auxiliary drive member.

Further, the pressurizing member functions as a driving member, and the fixing member functions as an auxiliary driving member. When the fixing member is braked, the air blowing position is brought closer to the discharge path of the recording medium from the fixing nip than the reference state, and the angle between the air blowing direction and the discharge direction of the recording medium from the fixing nip is formed. Is smaller than the reference state. When the fixing member is assisted, the air blowing position is moved away from the reference state from the recording medium discharge path from the fixing nip, and the air blowing direction and the recording medium discharge direction from the fixing nip are set. Make the angle to be made larger than the reference state. Thereby, the separability of the recording medium from the fixing member can be effectively improved.

Further, the pressurizing member functions as a driving member, and the fixing member functions as an auxiliary driving member. When the fixing member is braked, the angle between the air blowing direction and the paper ejection direction of the recording medium ejected from the fixing nip is made larger than the reference state without changing the air blowing position from the reference state. .. Then, when the fixing member is assisted, the angle formed by the air blowing direction and the paper ejection direction of the recording medium ejected from the fixing nip is set from the reference state without changing the air blowing position from the reference state. Make it smaller. As a result, the separability of the recording medium from the fixing member can be effectively improved, and the number of members can be reduced.

Further, at least one of the position and the inclination angle of the paper ejection side installation member arranged on the paper ejection side of the fixing nip is changed depending on whether the second member is to perform the braking operation or the assisting operation. .. As a result, the function of the paper ejection side installation member can be ensured, and the transportability of the recording medium can be stabilized.

Further, the air blowing position and the blowing angle are changed based on the operation performed by the second member and the type of the recording medium. As a result, it is possible to effectively improve the separability of the recording medium from the fixing member by determining whether to change the air blowing position and the blowing angle according to the quality of the separation of the recording medium, and it is unnecessary. Since changes in the air blowing position and blowing angle can be suppressed, a decrease in the productivity of printed matter can be suppressed.

Further, in order to control the gloss of the image based on the toner image T on the recording medium, it is controlled whether the second member is braked or assisted. As a result, the effect of causing the second member to perform the braking operation and the assisting operation can be used more effectively.

Further, the fixing member is made into a belt. As a result, when the fixing member is composed of a belt and one of the fixing member and the pressure member functions as an auxiliary drive member, the shape of the fixing nip on the discharge side of the recording medium changes with respect to the reference state. growing. This is because the slack of the belt is added in addition to the distortion of the roller. As a result, the effect of changing at least one of the air blowing position and the blowing angle for separating the recording medium from the fixing member is obtained depending on whether the second member is braked or assisted. Can be improved further.

The present invention is not limited to the embodiments described above.

For example, in the embodiment, paper has been described as an example of the storage medium, but the recording medium is not limited to paper, and may be a resin film or the like.

Further, in the embodiment, the air is blown out from the duct 531b, but the air may be blown out directly from the sirocco fan 531a in the blowing direction without providing the duct 531b.

Further, in the embodiment, a part or all of the processing executed by the program may be replaced with hardware such as a circuit and executed.

N fixing nip,
40 Imagery Department,
50 Fixing part,
51a fixing roller,
51b fixing belt,
51c heating roller,
53 Separation part,
531 air blowing mechanism,
531a Sirocco fan,
531b duct,
531c protrusion,
532 guidance member,
533 cam,
60 Paper feed section,
70 Paper transport section,
73 Discharge route,
73a Discharge direction,
74 Paper ejection guide,
75 Lower separation claw,
100 image forming device,
110 control unit,
120 storage,
130 communication department,
140 Operation display,
150 image reader,
160 image control unit,
170 Image forming part,
900 paper.

Claims (11)

A toner image forming unit that forms a toner image on a recording medium,
The toner image is formed by the pressurizing member and the fixing member that comes into contact with the unfixed toner image formed on the recording medium that is conveyed by the fixing nip formed by pressure contacting the pressurizing member. A fixing portion to be fixed to the recording medium with the fixing nip, and a fixing portion.
A separation unit that separates the recording medium on which the toner image is fixed from the fixing member by the blown air, and a separation unit.
By driving the first member of either the pressurizing member or the fixing member at a predetermined constant speed, the first member functions as a driving member for transporting the recording medium, and the other second member is fixed. Auxiliary drive that performs either a braking operation that increases the amount of microslip between the toner image and the fixing member in the nip from the reference state, or an assist operation that reduces the amount of microslip from the reference state. It has a control unit that functions as a member,
The control unit changes at least one of the air blowing position and the air blowing angle of the separating unit depending on whether the operation performed by the second member is the braking operation or the assisting operation. , Image forming device. By controlling the drive of the second member so that the drive torque of the first member increases from the reference state, the control unit causes the second member to perform the braking operation, and the second member operates from the reference state. The image forming apparatus according to claim 1, wherein the second member is made to perform the assist operation by controlling the drive of the second member so that the drive torque of the first member is reduced. The control unit controls the driving of the second member so as to reduce the surface speed of the second member with respect to the surface speed of the first member from the reference state, thereby causing the second member to perform the braking operation. By controlling the drive of the second member so as to increase the surface speed of the second member with respect to the surface speed of the first member from the reference state, the second member is made to perform the braking operation. , The image forming apparatus according to claim 1. The control unit
The pressurizing member is made to function as the driving member, and the fixing member is made to function as the auxiliary driving member.
When the fixing member is made to perform the braking operation, the blowing position of the air is brought closer to the discharge path of the recording medium from the fixing nip than the reference state, and the blowing angle of the air and the fixing nip When the angle formed by the discharge direction of the recording medium is made smaller than the reference state and the fixing member is made to perform the assist operation, the ejection position of the air is set to the discharge path of the recording medium from the fixing nip. Any one of claims 1 to 3, wherein the angle formed by the blowing angle of the air and the discharging direction of the recording medium from the fixing nip is made larger than the reference state. The image forming apparatus according to. The control unit
The pressurizing member is made to function as the driving member, and the fixing member is made to function as the auxiliary driving member.
When the fixing member is made to perform the braking operation, the blowing angle of the air and the discharging direction of the recording medium discharged from the fixing nip are obtained without changing the blowing position of the air from the reference state. When the angle formed by the paper is made larger than the reference state and the fixing member is made to perform the assist operation, the air is discharged from the fixing nip and the blowing angle of the air without changing the blowing position of the air from the reference state. The image forming apparatus according to any one of claims 1 to 3, wherein the angle formed by the paper ejection direction of the recording medium to be paper is made smaller than the reference state. The control unit further adjusts the position and inclination of the paper ejection side installation member arranged on the paper ejection side of the fixing nip, depending on whether the second member is to perform the braking operation or the assisting operation. The image forming apparatus according to any one of claims 1 to 5, wherein at least one of the angles is changed. The control unit changes the air blowing position and the blowing angle based on the operation performed by the second member and the type of the recording medium, according to any one of claims 1 to 6. Image forming device. The control unit controls whether to cause the second member to perform the braking operation or the assisting operation in order to control the gloss of the image based on the toner image on the recording medium, claims 1 to 7. The image forming apparatus according to any one of the above. The image forming apparatus according to any one of claims 1 to 8, wherein the fixing member is a belt. A toner image forming unit that forms a toner image on a recording medium,
The toner image is formed by the pressurizing member and the fixing member that comes into contact with the unfixed toner image formed on the recording medium that is conveyed by the fixing nip formed by pressure contacting the pressurizing member. A fixing portion to be fixed to the recording medium with the fixing nip, and a fixing portion.
A control program for an image forming apparatus having a separation unit that separates the recording medium on which the toner image is fixed from the fixing member by the blown air.
By driving the first member of either the pressurizing member or the fixing member at a predetermined constant speed, the first member functions as a driving member for transporting the recording medium, and the other second member is fixed. Auxiliary drive that performs either a braking operation that increases the amount of microslip between the toner image and the fixing member in the nip from the reference state, or an assist operation that reduces the amount of microslip from the reference state. Procedure (a) to function as a member and
The procedure (b) of changing at least one of the air blowing position and the air blowing angle of the separating portion depending on whether the operation performed by the second member is the braking operation or the assist operation. A control program for causing a computer to execute a process having. A toner image forming unit that forms a toner image on a recording medium,
The toner image is formed by the pressurizing member and the fixing member that comes into contact with the unfixed toner image formed on the recording medium that is conveyed by the fixing nip formed by pressure contacting the pressurizing member. A fixing portion to be fixed to the recording medium with the fixing nip, and a fixing portion.
A method executed by an image forming apparatus having a separation portion for separating the recording medium on which the toner image is fixed by the blown air from the fixing member.
By driving the first member of either the pressurizing member or the fixing member at a predetermined constant speed, the first member functions as a driving member for transporting the recording medium, and the other second member is fixed. Auxiliary drive that performs either a braking operation that increases the amount of microslip between the toner image and the fixing member in the nip from the reference state, or an assist operation that reduces the amount of microslip from the reference state. The stage (a) of functioning as a member and
The step (b) of changing at least one of the air blowing position and the air blowing angle of the separating portion depending on whether the operation performed by the second member is the braking operation or the assist operation. An air separation method having.

Images