JP5424035B2 - Fixing structure of rotational force generator and image forming apparatus - Google Patents

Description

  The present invention relates to a fixing structure of a rotational force generator and an image forming apparatus.

  In Patent Document 1, a drive system support frame made by integral molding using a resin material is attached to the outside of a side plate frame, and a gear is rotatably supported by the drive system support frame. A structure is described in which the tip is attached to a side plate frame and the movement of the gear in the thrust direction is restricted.

  Patent Document 2 describes a structure in which stepping motors individually connected to a plurality of photosensitive drums are fixed in series on a motor base, and the motor base is fixed to a frame via a cylindrical vibration-proof member. Has been.

  In Patent Document 3, in a structure in which a drive unit having a structure in which a heavy motor is cantilever-supported by a bracket is assembled to a main body frame, a through hole for mounting the motor on the main body frame is provided, and the motor is mounted around the through hole. A configuration with a time guide is described.

  Patent Document 4 discloses a structure in which a stepping motor for controlling the position of a magnetic head is fixed to a casing using a clamp that can be fixed at least at three points in an area that covers an angle range of about 180 degrees when viewed from the center of the stepping motor. Is described.

Japanese Patent Laid-Open No. 10-337929 Japanese Patent Laid-Open No. 11-30895 JP 2002-156877 A JP 2002-288950 A

Provided is a structure in which the fixed state of the rotational force generating means is stable .

The invention of claim 1 includes a rotary force generating device having projections including the rotation axis, a structure in which the protrusion is provided with a full recess fitted, fixed to the structure, before Kikai rolling by contacting the force generating equipment, presses the rotation preventing member for preventing rotation ago an axis of the protrusion of the Machinery rolling force generation equipment, a pre Machinery rolling force generator toward the structure pressing a member, prior Machinery rolling force generating equipment is by the protrusion state of fitted into the recess by the pressing member is fixed by being pressed against the structure, the pressing The member includes three convex portions that come into contact with the rotational force generator at three locations, and the rotational force generator includes a rotor shaft and an output shaft that is driven from the rotor shaft via a gear, The three convex portions are triangular with one side being a straight line connecting the rotor shaft and the output shaft. It is a fixed structure of the torque generating apparatus according to claim which is located at the apex of the.

According to a second aspect of the present invention, there is provided a rotational force generator including a protrusion including a rotation shaft, a structure including a recess into which the protrusion is fitted, and the rotational force generator fixed to the structure. An anti-rotation member that prevents rotation about the projection of the rotational force generating device as a shaft, and a pressing member that presses the rotational force generating device toward the structure, and the rotational force generator, by the protrusion state of fitted into the recess by the pressing member is fixed by being pressed against the structure, the pressing member is 3 before Kikai rolling force generating equipment comprises three protrusions that contact at a point, before Kikai rolling force generating equipment includes a rotor shaft, an output shaft driven through a gear from the rotor shaft, said three protrusions, the Rotor shaft, output shaft, center of gravity of the rotational force generator It is a fixed structure of the torque generating apparatus according to claim that the at least one point selected laid et located at the vertices of a triangle whose vertices.

According to a third aspect of the present invention, there is provided a rotational force generator having a protrusion including a rotating shaft, a structure having a recess into which the protrusion is fitted, and the rotational force generator fixed to the structure. An anti-rotation member that prevents rotation about the projection of the rotational force generating device as a shaft, and a pressing member that presses the rotational force generating device toward the structure, and the rotational force generator, by the protrusion state of fitted into the recess by the pressing member is fixed by being pressed against the structure, the pressing member is 3 before Kikai rolling force generating equipment comprises three protrusions that contact at a point, before Kikai rolling force generating equipment includes a rotor shaft, an output shaft driven through a gear from the rotor shaft, said three protrusions, the Three around the center of gravity of the output shaft or the motor It is a fixed structure of the torque generating apparatus according to claim which is located at each vertex form.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the pressing member is constituted by a member that performs electromagnetic shielding of the electronic board.

The invention according to claim 5 is the invention according to any one of claims 1 to 4 , wherein the rotation preventing member is constituted by a member that holds a gear that transmits the driving force of the motor. It is characterized by.

The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein a plurality of the rotational force generating devices are provided.

The invention according to claim 7 is a plurality of torque generators fixed to the housing by the fixing structure of the torque generator according to any one of claims 1 to 5 , and the torques of the plurality of torque generators. An image forming apparatus comprising: a plurality of image holders each having a cylindrical shape that is arranged for each of the generating devices and is rotated by a driving force from each of the plurality of rotating force generating devices.

According to the invention described in claim 1, the fixed state of the torque generating means as compared with the case of not using the invention described in claim 1 is stabilized.

According to the invention described in claim 2, the fixed state of the torque generating means as compared with the case of not using the invention described in claim 2 is stabilized.

According to the invention described in claim 3, the fixed state of the torque generating means as compared with the case of not using the invention described in claim 3 is stabilized.

According to the invention described in claim 4, noise leaking comparison from the motor to the electronic board in the case of not using the invention described in claim 4 is suppressed.

According to the invention of claim 5, the use efficiency of the components is increased as compared with the case of not using the invention described in claim 5.

According to invention of Claim 6, the fixing structure which does not fix each of several rotational force generation means separately is provided.

According to the invention described in claim 7, an image forming apparatus having the advantages of the invention described in any one of claims 1-5 is provided.

1 is a conceptual diagram of an image forming apparatus according to an embodiment. FIG. 2 is a perspective view showing a frame assembled to the image forming apparatus of FIG. 1. It is a perspective view which shows the state which assembled | attached the motor unit to the flame | frame of FIG. It is a perspective view of a motor unit. It is a perspective view of a motor unit. It is a perspective view which shows the shield sheet metal pressed against a flame | frame. It is a perspective view which shows the state which fixed the motor unit to the housing | casing. It is a perspective view which shows the state which fixed the motor unit to the housing | casing. It is a perspective view which shows the state which fixed the electronic substrate to the back surface of a shield sheet metal.

(Outline of image forming apparatus)
FIG. 1 shows an image forming apparatus 100 according to the embodiment. The image forming apparatus 100 includes a paper storage device 101. The paper storage device 101 stores a plurality of papers 102 for forming an image. The paper stored in the paper storage device 101 is transported toward the secondary transfer unit 106 through the transport path 105 by the functions of the transport roll mechanisms 103 and 104.

  In the secondary transfer unit 106, the toner image formed on the transfer belt 107 is secondarily transferred onto the paper. The sheet on which the toner image is transferred in the secondary transfer unit 106 is sent to the image fixing unit 108 where heat and pressure are applied. As a result, the toner image on the paper is fixed on the paper as an image. The sheet on which the image has been fixed is discharged from the discharge roll mechanism 109 to the sheet discharge surface 110.

  A toner image of each color of YMCK is primarily transferred from the primary transfer units 120, 130, 140 and 150 to the fixing belt 107. The primary transfer units 120, 130, 140, and 150 have the same structure except that the color of the toner image to be formed is different.

  For example, the primary transfer unit 120 includes a photosensitive drum 121 and a developing roll 122 that develops an electrostatic latent image formed on the photosensitive drum 121. An exposure device (not shown), a charging device (not shown), and a cleaning device (not shown) for forming an electrostatic latent image are arranged on the photosensitive drum 121 along the clockwise direction in the drawing. . An image (toner image) (for example, a Y color toner image) developed on the photosensitive drum 121 is primarily transferred onto the transfer belt 107.

  This primary transfer is also performed in the primary transfer units 130, 140, and 150, and toner images of basic colors of YMCK are superimposed. Thus, the primary transfer of the image onto the transfer belt 107 is performed.

  In this image forming operation, the photosensitive drum and the developing roll of each primary transfer unit rotate. This rotational driving force is performed by a motor unit that functions as a rotational force generator prepared for each primary transfer unit and a transmission gear device that transmits the driving force from the motor unit.

  That is, the driving force for driving the photosensitive drum 121 and the developing roll 122 of the primary transfer unit 120 is supplied from the motor unit 123. The motor unit 123 incorporates an outer rotor type (a type in which the outside rotates) and a gear mechanism. The driving force output from the motor unit 123 is transmitted to the transmission gear device 124, from which it is branched and transmitted to the photosensitive drum 121 and the developing roll 122.

  Similarly, a driving force is transmitted from the motor unit 133 to the photosensitive drum 131 and the developing roll 132 of the primary transfer unit 130 via the transmission gear device 134. A driving force is transmitted from the motor unit 143 to the photosensitive drum 141 and the developing roll 142 of the primary transfer unit 140 via the transmission gear device 144. A driving force is transmitted from the motor unit 153 to the photosensitive drum 151 and the developing roll 152 of the primary transfer unit 150 via the transmission gear device 154.

(Motor unit fixing structure)
Hereinafter, a structure for fixing the motor units 123, 133, 143, and 153 of FIG. 1 to the image forming apparatus 100 will be described. FIG. 2 shows a frame 201 to which four motor units are fixed. The frame 201 is a member to which four motor units are fixed, and has a structure in which a steel plate is press-formed. The frame 201 is screwed to the housing of the image forming apparatus 100 and integrated there. With this structure, the frame 201 functions as a part of the housing of the image forming apparatus 100. Further, the frame 201 is secured to the casing of the image forming apparatus 100 and is in a state where it can be used as an electrical ground (housing ground).

  FIG. 3 shows a state where the motor units 123, 133, 143 and 153 are temporarily fixed to the frame 201 shown in FIG. 2 (a state where the motor units 123, 133, 143 and 153 are not fixed by the fixing means).

  Hereinafter, the motor unit will be described. The four motor units 123, 133, 143 and 153 have the same structure. Here, the motor unit 123 will be described as a representative. The motor unit 123 is shown in FIGS. The motor unit 123 has a structure in which a motor and a gear mechanism are held between a pair of support plates 301 and 302.

  An outer rotor type motor 303 is held between the pair of support plates 301 and 302. The motor 303 includes a rotating rotor 304, and gear teeth (not shown) are formed on the outer periphery of the rotor 302. The rotor 304 has a structure in which the rotor shaft 304a is held by the support plates 301 and 302 in a rotatable state. The rotation of the rotor 304 is decelerated in the process of transmitting a plurality of gears, and is finally transmitted to the rotation shaft (output shaft) 306 of the gear 305. That is, when the motor 301 is operated, the rotor 304 rotates and the rotation is transmitted to the gear 305. This rotation is output from the output shaft 306. Reference numeral 308 denotes a spacer that holds the support plates 301 and 302 facing each other with a gap therebetween.

  As shown in FIG. 4, the support plate 301 is provided with a protrusion 307. The protrusion 307 has a disk shape (a donut shape) having a through-hole that holds the output shaft 306 in a rotatable state at the center. In FIG. 4, the output shaft 306 has a shape that is cut off at the same position as the end face of the protrusion 307, but actually extends and extends in the Y-axis direction.

  Hereinafter, a structure for fixing the motor unit 123 to the frame 201 will be described. As shown in FIG. 2, contact portions 202, 203, and 204 that are in contact with the motor unit 123 are provided on the frame 201 side. A rubber serving as a buffer material is attached to the tip portions of the contact portions 202, 203, and 204, and is configured to contact the motor unit 123 in a state having a buffer action. As the buffer material, various polymer materials, fibrous materials, disc springs, and the like can be used.

  Further, a positioning cylindrical portion 205 for positioning the motor unit 123 is provided at a portion of the frame 201 where the motor unit 123 is fixed. The positioning cylindrical portion 205 has a structure in which the protruding portion 307 of FIG. 4 can be fitted inside. 3 shows a state in which the protrusion 307 (see FIG. 4) of the motor unit 123 is fitted inside the positioning cylindrical portion 205 of FIG. 2, and the contact portions 202, 203, and 204 are brought into contact with the support plate 301. ing.

  In the state shown in FIG. 3, the hypotenuse 302 a of the support plate 302 (see FIGS. 2 and 3) of the motor unit 123 is in contact with the drive transmission gear holding metal plate 210. The drive transmission gear holding sheet metal 210 is a sheet metal screwed to the frame 201 and transmits the driving force from the motor unit 123 to the photosensitive drum 121 and the developing roll 122 of the primary transfer unit 120 (see FIG. 1). The transmission gear device 124 (details omitted) is held. Further, in this structure, the drive transmission gear holding metal plate 210 functions as a rotation preventing member that prevents the motor unit 123 from rotating about the Y axis when the hypotenuse 302a of the support plate 302 contacts.

  That is, in the state shown in FIG. 3, the motor unit 123 is in a state in which the protruding portion 307 (see FIG. 4) protruding from the support plate 301 is fitted in the positioning cylindrical portion 205 (see FIG. 2) of the frame 201. . In this state, the position of the motor unit 123 on the XZ plane (the plane of the frame 201) is determined. And the hypotenuse 302a (refer FIG. 4) contacts the drive transmission gear holding | maintenance metal plate 210, and it is set as the structure where the rotation of the motor unit 123 centering on the protrusion part 307 does not arise. Thus, the motor unit 123 is positioned on the frame 201 and cannot rotate. In other words, the motor unit 123 cannot move and rotate relative to the frame 201 in the XZ plane.

  The above structure is the same in the motor units 133, 143, and 153. In the state shown in FIG. 3, the motor units 123, 133, 143, and 153 are prevented from moving in the XZ plane with respect to the frame 201, but can be separated from the frame 201 in the Y-axis direction. It is supposed to be ready. That is, each motor unit is temporarily fixed to the frame 201.

  3, the output shafts from the motor units 133, 143, and 153 pass through the inside of four positioning cylindrical portions (one of which is denoted by reference numeral 205 in FIG. 2) provided on the frame 201. 2 and protrudes beyond the frame 201 in FIG. 3 (Y-axis positive direction side). A gear (not shown) is attached to the projecting output shaft of each motor unit, and meshes with a gear included in a gear mechanism held by a drive transmission gear holding metal plate (one of which is indicated by reference numeral 210). It is supposed to be in a state.

  FIG. 6 shows a shield metal plate 220 that is used when the motor units 123, 133, 143, and 153 are pressed against the frame 201 side. The shield metal plate 220 is made of a steel plate, and electrical continuity with the frame 201 is ensured. As will be described later, the shield metal plate 220 electromagnetically shields between the motor unit group and the electronic board.

  A pressing plate 221 is fixed to the surface of the shield metal plate 220 facing the frame 201 (see FIGS. 2 and 3). The pressing plate 221 is made of a steel plate, and electrical continuity is ensured between the shield sheet metal 220 and the frame 201. The pressing plate 221 is provided with regions 222, 223, 224, and 225 each having three protrusions. For example, the region 222 is provided with protrusions 231, 232, and 233. In the region 223, protrusions 241, 242, and 243 are provided. These protrusions are formed when the pressing plate 221 is formed by press molding, and are part of the pressing plate 221.

  Each of the three protrusions provided in the regions 222, 223, 224, and 225 has a positional relationship in which each vertex of the equilateral triangle is located.

  The shield metal plate 220 is pressed against the frame 201 of FIGS. 2 and 3 with the pressing plate 221 facing the frame 201 and is fixed to the frame 201 with screws. At this time, the three protrusions (reference numerals 231, 232, 233) in the region 222 of the pressing plate 221 come into contact with the support plate 302 (see FIG. 4) of the motor unit 123 in the state of FIG. Thus, the motor unit 123 is sandwiched between the frame 201 and the pressing plate 220, and the motor unit 123 is fixed to the frame 201.

  Similarly, the motor unit 133 is pressed toward the frame 201 by the three protrusions in the region 223 of the pressing plate 221, and is fixed to the frame 201 while being sandwiched between the frame 201 and the pressing plate 221. . Similarly, the motor unit 143 is pressed toward the frame 201 by the three protrusions in the region 224 of the pressing plate 221, and is fixed to the frame 201 while being sandwiched between the frame 201 and the pressing plate 221. . Similarly, the motor unit 153 is pressed toward the frame 201 by the three protrusions in the region 225 of the pressing plate 221, and is fixed to the frame 201 while being sandwiched between the frame 201 and the pressing plate 221. .

  A position where each of the three protrusions on the pressing plate 221 side contacts each motor unit will be described. FIG. 7 shows the positional relationship of the protrusions 231, 232 and 233 of the pressing plate 221 shown in FIG. 6 with respect to the motor unit 133.

  FIG. 8 is a cutaway view showing a state in which the motor unit 123 is fixed to the frame 201 by being sandwiched between the frame 201 and the pressing plate 221. FIG. 8 shows a semicircular ear 244 of the pressing plate 221 also shown in FIG. The ear 244 is provided with a protrusion 232 (see FIG. 6). As shown in FIGS. 7 and 8, the protrusion 232 contacts the position of the output shaft 306 of the motor unit 123 and pushes it there.

  According to this structure, the three protrusions 231, 232, and 233 disposed in the region 222 shown in FIG. 6 are disposed at the apex of the equilateral triangle, and the protrusion 232 at one of the apexes of the motor unit 123. The structure is such that the end portion of the output shaft 306 is pushed.

  The protrusion 233 is in contact with the position (rotor center) of the shaft (rotor shaft 304a in FIG. 4) of the rotor 304 of the motor provided in the motor unit 143. According to this structure, the motor at each vertex (three points) of a triangle having two vertexes, the position of the output shaft 306 and the position of the rotor center (rotor shaft 304a) of the motor unit 123 shown in FIGS. The unit 123 is pressed against the frame 201 side by the pressing plate 221. This triangle is most preferably an equilateral triangle in order to distribute the force evenly, but may be an isosceles triangle.

  In addition, the code | symbol 205 of FIG. 8 is the cylindrical part for positioning provided in the flame | frame 201 (refer FIG. 2). The output shaft of the motor unit 123 passes through the inside of the positioning cylindrical portion 205. Although not shown, the output shaft 306 (see FIG. 4) of the motor unit 123 that penetrates the inside of the positioning cylindrical portion 205 protrudes from the opening 205a provided in the frame 210 in the positive direction of the Y axis in the figure. Yes. A gear (not shown) is attached to the output shaft 306, and the driving force is transmitted to the transmission gear device 124 of FIG. 1 via the gear.

  In the state shown in FIG. 7, an electronic board is further attached. FIG. 9 shows a state in which the electronic board 250 is attached to the frame 201 with screws. A drive circuit (not shown) for driving the motor units 123, 133, 143, and 153 is mounted on the surface of the electronic substrate 250 that faces the shield metal plate 220.

(Superiority)
As described above, in the structure in which the motor units 123, 133, 143, and 153 are fixed to the frame 201 that is fixed to and integrated with the casing of the image forming apparatus 100, the frame 201 is assembled with each motor unit assembled. Each motor unit is pressed and fixed by a pressing plate that presses each motor. Each motor unit includes a protrusion (for example, reference numeral 307) that holds the output shaft, and the protrusion is fitted into a positioning recess (for example, inside the positioning cylinder 205) provided on the frame 201. , Positioned with respect to the frame 201.

  According to this configuration, the drive of the image forming apparatus 100 is divided for each of the four primary transfer units 120, 130, 140, and 150. In other words, a drive source is prepared independently for each of the four primary transfer units. For this reason, a gear train that is necessary when the drive source is shared by a plurality of primary transfer units is not necessary, and the space for that can be reduced, so that downsizing can be pursued. Moreover, since a complicated gear mechanism can be omitted, simplification and cost reduction can be achieved.

  The four motor units are in contact with the frame 201 at three points. For this reason, the stable contact state without backlash is ensured. Further, the contact of the motor unit with the frame 201 is a contact through a cushioning material. Therefore, transmission of vibration from the motor unit to the frame 201 during operation is suppressed, and a noise suppression effect and an image quality improvement effect are obtained.

  The four motor units are fixed in a state of being pressed against the frame 201 by the pressing plate 221. In this structure, each motor unit is not individually fixed to the frame 201, so that it is possible to reduce the parts and work required for fixing. For this reason, part cost can be reduced and assemblability can be improved.

  The pressing plate 221 presses the motor unit at three points, and one of the three points is the position of the output shaft of the motor unit, and the other point is the position of the rotor shaft of the motor. For this reason, the motor unit can be stably held, and displacement, rotation, and the like due to vibration can be effectively suppressed.

  A pressing plate 221 is in contact with the back surface of the motor unit, and a shield metal plate 220 is further positioned behind the pressing plate 221. The pressing plate 221 and the shield metal plate 220 are kept at the ground potential of the casing. For this reason, grounding of the motor unit is strengthened, and leakage noise from the motor unit can be suppressed. In addition, since the electromagnetic shield member is doubled between the motor unit and the circuit board 250, the propagation of noise from the motor unit to the electronic circuit on the circuit board 250 is suppressed. Further, since the pressing plate 221 and the shield metal plate 220 also function as a heat sink, the heat dissipation effect from the motor unit can be enhanced.

(Other examples of protrusion positions)
In the structure described above, one of the apexes of three projections (for example, reference numerals 231, 232, and 233) for restraining the motor unit provided on the pressing plate 221 is the position of the output shaft of the motor unit. It is shown. As a design for obtaining a stable fixed state of the motor unit, there can be mentioned a configuration in which the projections at the three points are the positions of the vertices of the equilateral triangle and the position of the center of gravity of the equilateral triangle is the position of the output shaft of the motor unit . In addition, a configuration in which the projections at the three points are used as the positions of the vertices of the equilateral triangle and the position of the center of gravity of the equilateral triangle is used as the position of the center of gravity of the motor unit can be cited. In these configurations, since the pressure balance applied to the motor unit in a fixed state with respect to the frame of the motor unit becomes uniform, a stable fixed state can be obtained.

(Other examples of frames)
The frame 201 may have a function of holding a gear shaft and a drive shaft. According to this configuration, since the frame 201 has a plurality of functions, the use efficiency of components constituting the image forming apparatus is increased, and the number of components can be reduced.

  The present invention can be used for a fixing structure of a rotational force generator and an image forming apparatus.

DESCRIPTION OF SYMBOLS 100 ... Image forming apparatus, 101 ... Paper storage apparatus, 102 ... Paper, 103 ... Conveyance roll mechanism, 104 ... Conveyance roll mechanism, 105 ... Conveyance path, 106 ... Secondary transfer part, 107 ... Transfer belt, 108 ... Image fixing part , 109 ... discharge roll mechanism, 120 ... primary transfer unit, 130 ... primary transfer unit, 140 ... primary transfer unit, 150 ... primary transfer unit, 121 ... photosensitive drum, 122 ... developing roll, 123 ... motor unit , 124 ... transmission gear device, 131 ... photosensitive drum, 132 ... developing roll, 133 ... motor unit, 134 ... transmission gear device, 141 ... photosensitive drum, 142 ... developing roll, 143 ... motor unit, 144 ... transmission gear device , 151 ... photosensitive drum, 152 ... developing roll, 153 ... motor unit, 154 ... transmission gear device, 2 DESCRIPTION OF SYMBOLS 1 ... Frame, 202 ... Contact part, 203 ... Contact part, 204 ... Contact part, 205 ... Cylindrical part for positioning, 210 ... Drive transmission gear holding sheet metal, 220 ... Shield sheet metal, 221 ... Pressing plate, 222 ... Three protrusions A region provided with two protrusions, 224 a region provided with three protrusions, 225 a region provided with three protrusions, 231 a protrusion, 232 a protrusion, 233 a protrusion, 241 a protrusion, 242 ... Projection, 243 ... Projection, 244 ... Ear part, 250 ... Circuit board, 306 ... Output shaft.

Claims (7)

A rotational force generating device having projections including the rotation axis,
A structure having a recess into which the protrusion fits;
Is fixed to the structure, before by contacting the Kikai rolling force generating equipment, a rotation prevention member for preventing rotation ago an axis of the protrusion of the Machinery rolling force generating equipment,
The pre Machinery rolling force generating device and a pressing member pressing towards the structure,
Before Machinery rolling force generating equipment is by the protrusion state of fitted into the recess by the pressing member is fixed by being pressed against said structure,
The pressing member includes three convex portions that come into contact with the rotational force generating device at three locations,
The rotational force generator includes a rotor shaft and an output shaft driven from the rotor shaft via a gear,
The three convex portions are located at the apex of a triangle having a straight line connecting the rotor shaft and the output shaft as one side . A rotational force generator having a protrusion including a rotation shaft;
A structure having a recess into which the protrusion fits;
An anti-rotation member that is fixed to the structure and prevents rotation about the protrusion of the rotational force generator by contacting the rotational force generator;
A pressing member that presses the rotational force generator toward the structure;
With
The rotational force generating device is fixed by being pressed against the structure by the pressing member in a state in which the protrusion is fitted in the recess.
The pressing member is provided with three protrusions that contact with three places before Kikai rolling force generating equipment,
Before Machinery rolling force generating equipment is provided with a rotor shaft, an output shaft driven through a gear from the rotor shaft,
The three convex portions are located at the apex of a triangle having at least one point selected from the position of the center of gravity of the rotor shaft, the output shaft, and the rotational force generating device. The fixed structure of the device. A rotational force generator having a protrusion including a rotation shaft;
A structure having a recess into which the protrusion fits;
An anti-rotation member that is fixed to the structure and prevents rotation about the protrusion of the rotational force generator by contacting the rotational force generator;
A pressing member that presses the rotational force generator toward the structure;
With
The rotational force generating device is fixed by being pressed against the structure by the pressing member in a state in which the protrusion is fitted in the recess.
The pressing member is provided with three protrusions that contact with three places before Kikai rolling force generating equipment,
Before Machinery rolling force generating equipment is provided with a rotor shaft, an output shaft driven through a gear from the rotor shaft,
The three convex portions are located at the apexes of a triangle centered on the output shaft or the center of gravity of the motor. The structure for fixing a rotational force generating device according to any one of claims 1 to 3 , wherein the pressing member is configured by a member that performs electromagnetic shielding of an electronic board. It said anti-rotation member fixing structure of the torque generating apparatus according to any one of claims 1 to 4, characterized in that it is constituted by a member for holding a gear for transmitting the driving force of the motor. The rotational structure of the rotational force generator according to any one of claims 1 to 5, wherein there are a plurality of the rotational force generators . A plurality of rotational force generators fixed to the housing by the rotational force generator fixing structure according to any one of claims 1 to 5 ,
An image forming apparatus comprising: a plurality of image holders each having a cylindrical shape that is arranged for each of the plurality of torque generators and is rotated by a driving force from each of the plurality of torque generators. .

Images