JP2009103840A - Driving force transmission apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a structure at a reduced cost in which engaging precision of gears is satisfactory and having no occurrence of oscillation nor rotational variation. <P>SOLUTION: The driving force transmission apparatus is provided with: a driving unit with a driving force generating means for generating driving force, a driving gear 22 which is rotated and driven by the driving force, and a driving shaft 23 for transmitting the driving force from the driving force generating means to the driving gear 22; and a following unit 3 with a following gear 31 driving rotation by engaging with the driving gear 22, a driven shaft 32 for retaining the following gear 31 and a rotating body fixed to the driven shaft 32. When central positions of the driving shaft 23 and the driven shaft 32 during the driving of the driving unit are point A and point B, an angle formed by a line segment AB with a horizontal surface is α and a pressure angle of the driving gear 22 is β, the central position of the driven shaft 32 when the driving unit is not driven exists on a line inclined in the opposite direction to the rotating direction of the driven shaft 32 by an angle α-β to a perpendicular line to the line segment AB. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a driving force transmission device and an image forming apparatus used for image formation such as a copying machine, a printer, and a FAX.

2. Description of the Related Art Conventionally, gears are employed as a driving force transmission means in various machines, and in particular, a large number of gears are used in image forming apparatuses such as copiers, printers, and fax machines. In recent years, OA equipment such as copying machines has been improved in image quality and speed, and accordingly, driving force transmission parts such as gears are required to have high durability and high accuracy. However, it has become necessary to rotate the gears at a higher speed as the speed of the image forming apparatus increases, and vibration and noise increase when the gears mesh with each other has become a problem. In addition, there is a demand for downsizing and a reduction in the number of drive motors installed in the image forming apparatus, and the number of gears used is increasing to satisfy the demand, which is also a cause of increased vibration and noise. It has become.
In addition, the image forming apparatus has a configuration in which a unitized developing device, transfer device, etc. are mounted on the product body in order to facilitate replacement of consumables and to prevent failure. The driving force generated by the motor needs to be transmitted to a driven unit such as a developing device or a transfer device, and a gear is used as the driving force transmitting component.

When the driving force is transmitted from the driving motor to each driven unit, the driven unit is inclined with respect to the product body, the gear shaft is misaligned, or the driven unit is in a predetermined position. If they are not aligned with each other, there will be a shift in the meshing of the gears, and it will not be possible to transmit the driving force sufficiently, and the rotation of the shaft will become unstable. There was a problem that led to the outbreak.
More specifically, when the rotation of the shaft becomes unstable and rotation fluctuation occurs, the interval between the developing roller and the photoconductor changes, and the density unevenness in the form of pitch according to the rotation cycle of the developing roller or photoconductor, that is, banding. Has occurred in the image. Further, when the vibration propagates to the driven unit, the vibration is generated in the lens, the mirror, etc., causing the beam position to fluctuate. This variation in beam position also causes banding. As described above, if the driving force cannot be accurately transmitted from the product body to the unit, high-quality image formation cannot be performed.

Incidentally, as a means for smoothly connecting gears, for example, Patent Document 1 is known. In Patent Document 1, when inserting a unit, the shaft core of the unit side gear is shifted outward with respect to the gear on the main body side, and the shaft core is brought closer to the shaft center of the gear on the main body side from the position overlapping in the tooth width direction. By doing so, the clearance between the shaft and the gear and the backlash between the front and rear gears are reduced, and rotational fluctuation and vibration are reduced.
In Patent Document 2, by providing a plurality of positioning means along the direction of the radial force acting on the gear tooth surface, the tooth surface is not affected by the radial force generated when the gear meshes. Position accuracy can be maintained, and vibration and rotation fluctuations can be prevented.
In patent document 3, it can rotate without receiving a thrust force by making a gear into a tooth-gear gear. The sliding contact between the unit and the gear is prevented.

JP 2002-304030 A JP 2000-147852 A Japanese Patent Laid-Open No. 8-160832

However, in the technique disclosed in Patent Document 1, since the detachable unit is guided at a position not parallel to the mounting position, there is a concern that the rotation shaft may be inclined. If the gears are engaged with the rotating shaft tilted, the occurrence of vibrations and rotation fluctuations cannot be suppressed. In addition, there is a concern that the rotating shaft may be inclined due to the radial force generated when the gear is engaged.
Further, in the technique disclosed in Patent Document 2, a load is applied to the positioning unit due to long-time use of the image forming apparatus, and there is a concern that the positioning unit may fall down or be chipped. Further, the radial force is generated in the direction inclined by the pressure angle from the tangential direction at the meshing position due to the influence of the pressure angle of the gear. For this reason, even if positioning is performed on the line of action in the radial direction, a force is actually applied in a direction shifted by the pressure angle, resulting in a reduction in gear meshing accuracy.
Further, in Patent Document 3, it is proposed to use a tooth-gear gear that cancels out the thrust force. However, the shape of the tooth-gear gear is complicated, so that it is difficult to perform the molding process and a sufficient number of gears are required. There is a problem that the shape accuracy cannot be ensured. Moreover, in order to ensure the shape accuracy of the gear, there is a problem in terms of cost, for example, it is necessary to use a special processing method or material.

  Therefore, the present invention has been made in view of the above-mentioned problems, and its object is to achieve inexpensively a structure in which the meshing accuracy of gears is good and vibration and rotation fluctuations are not generated. .

The features of the present invention, which is a means for solving the above problems, are listed below.
The driving force transmitting device of the present invention includes a driving force generating means for generating a driving force, a driving gear that is rotationally driven by the driving force, and a driving shaft that transmits the driving force from the driving force generating means to the driving gear. A drive unit comprising: a drive unit including: a drive gear that meshes with the drive gear and rotationally drives; a driven shaft that holds the driven gear; and a rotary unit that is fixed to the driven shaft. In the transmission device, the center positions of the drive shaft and the driven shaft during driving of the drive unit are point A and point B, respectively, α is the angle between the line segment AB and the horizontal plane, and β is the pressure angle of the drive gear. In this case, the center position of the driven shaft when the drive unit is not driven is located on a line inclined in the direction opposite to the rotation direction of the driven shaft by an angle α-β with respect to the perpendicular of the line segment AB.
The driving force transmission device of the present invention further includes a fixing member that fixes the driving shaft to the driving unit.
Moreover, the driving force transmission device according to the present invention is further characterized in that the fixing member is arranged along a direction inclined by an angle α-β with respect to a perpendicular line of the line segment AB.
Further, in the driving force transmission device of the present invention, the driving gear and the driven gear are helical gears, and an angular difference between the radial direction of the driven shaft when the driving unit is driven and the radial direction of the driven gear is determined. In the case of λ, the drive shaft is fixed at an angle λ with respect to the drive unit.
Further, in the driving force transmission device according to the present invention, the driven shaft is inserted into a long hole formed in the driving unit, and the long shaft is formed along a direction inclined by an angle α-β with respect to a perpendicular of the line segment AB. The drive unit is assembled so that the hole is disposed, and the center of the driven shaft coincides with the point B in a state where the driven shaft is restrained from moving at one end of the elongated hole when the drive unit is driven. Features.
An image forming apparatus according to the present invention includes any one of the driving force transmission devices described above.

  In the driving force transmission device as the means to solve the above, a gear meshing accuracy is good, and a structure capable of suppressing the occurrence of vibration and rotation fluctuation can be achieved at low cost.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.

FIG. 1 is a schematic diagram showing the configuration of the image forming apparatus of the present invention.
As shown in FIG. 1, an intermediate transfer body T that moves endlessly in the direction of the arrow is provided inside the image forming apparatus main body, and four image forming units L1Y, L1C, L1M and L1K are deployed. Y, C, M, and K along the numbers of the image forming units correspond to the colors of the toners to be handled. Y represents yellow, C represents cyan, M represents magenta, and K represents black. . R1Y, R1C, R1M, and R1K transfer rollers are provided inside the intermediate transfer member T so as to face the photosensitive member L2 that is provided in the image forming unit and rotates together with the intermediate transfer member T. Note that the photoreceptors L2Y to L2K, which are to be charged, are arranged at the same interval, and at least at the time of image formation, are in contact with a part of the stretched portion with the intermediate transfer member T.
In FIG. 1, during operation of the image forming apparatus, charging that is charging means is performed around a cylindrical photosensitive member L2 rotatably supported by a driving source (not shown) so as to rotate in the direction of an arrow according to an electrophotographic process. A transfer roller R1 is disposed via an image forming member such as an apparatus L3, a developing device L4, a cleaning member L5 which is a transparent electrode, and an exposure device L6 which is a light source, and an intermediate transfer member T.
The photoreceptor L2 is obtained by forming an organic photosensitive layer (OPC), which is a photoconductive substance, on an aluminum cylinder surface having a diameter of about 30 to 120 mm, for example. A photoreceptor L2 on which an amorphous silicon (a-Si) layer is formed can also be used. A belt-like photoreceptor L2 can also be employed.

The exposure device L6 scans the surface of each photoreceptor L2 that has been uniformly charged by the charging device L3 with light corresponding to the image data for each color, and forms an electrostatic latent image. The exposure apparatus uses a laser beam and a polygon mirror, and can adopt a laser scanning method using a beam light modulated in accordance with image data to be formed, or an LED (light emitting diode) array and an imaging element method as light emitting elements.
In addition to the roller charging method, a charging method that does not contact the photosensitive member L2 can be employed as the charging device L3.
The development in this embodiment is a development system that employs a two-component developer composed of toner and carrier. The electrostatic latent image for each color formed on the surface of each photosensitive member L2 by a laser beam with respect to the negatively charged photosensitive member L2 is a toner of a predetermined color having the same polarity (negative polarity) as the charged polarity of the photosensitive member L2. Development is performed and reversal development is performed to form a visible image. A detailed description of the configuration of the developing device L4 is omitted. An intermediate transfer member T that is supported by a plurality of rollers R6, R7, and R8 and runs in the direction of the arrow is provided above the photosensitive members L2Y, L2C, L2M, and L2K. This intermediate transfer member T is endless, and is stretched and arranged so that a part of each photosensitive member L2 after the developing process comes into contact. In addition, primary transfer rollers R1Y, R1C, R1M, and R1K are provided on the inner peripheral portion of the intermediate transfer member T so as to face the photoconductors L2Y, L2C, L2M, and L2K.
A cleaning device L9 is provided on the outer peripheral portion of the intermediate transfer member T at a position facing the roller R6. The cleaning device L9 wipes off unnecessary toner remaining on the surface of the intermediate transfer member T and foreign matters such as paper dust. Further, a secondary transfer roller R5 is provided on the outer periphery of the intermediate transfer member T in the vicinity of the support roller. By applying a bias to the secondary transfer roller R5 while passing a recording medium (hereinafter referred to as paper P) between the intermediate transfer body T and the secondary transfer roller R5, the toner image carried by the intermediate transfer body T becomes the paper P. Is transcribed. The polarity of the transfer current applied to the secondary transfer roller R5 is a positive polarity opposite to the polarity of the toner.

Below the image forming apparatus L, a paper feeding device L8 that accommodates paper is provided so that only one sheet is reliably sent to the registration roller R3 by the transport roller R2. Further, the sheet that has passed the secondary transfer roller R5 is conveyed to a fixing device L10 provided downstream in the conveyance direction of the recording medium.
As the fixing device L10 having a heating means, a type having a heater inside a roller, a belt fixing device for running a heated belt, a fixing device L10 adopting induction heating as a heating method, or the like can be adopted. The fixing device L10 is controlled by a control unit (not shown) so as to control fixing conditions based on full-color and monochrome images, single-sided or double-sided, and optimal fixing conditions according to the type of paper P. The fixed paper P is discharged and stacked on a paper discharge stack provided at the top of the image forming apparatus L by a paper discharge roller R4.
Each color toner cartridge L7Y, L7C, L7M, L7K containing unused toner is detachably accommodated in the space above the photoreceptor L2. Toner is supplied to each developing device L4 as required by toner conveying means such as a mono pump or air pump (not shown). The toner cartridge L7K for black toner that is highly consumed can be set to have a particularly large capacity.

An operation for forming a full-color image in the above configuration will be described.
In the present embodiment, the image carried on the intermediate transfer member T from the configuration of the image forming apparatus L is transferred to the paper P, and even when the data to be recorded becomes a plurality of pages when transferred, the pages on the paper discharge stack portion. The images are formed on the lower surface of the paper P so that
When the image forming apparatus 1 is operated, the photoreceptors L2Y, L2C, L2M, and L2K in the image forming unit L1 that is in contact with the intermediate transfer member T rotate. First, image formation by the image forming unit L1 is started. By the operation of the exposure device L6 driven by the laser and the polygon mirror, the light corresponding to the image data for yellow is irradiated onto the surface of the photoreceptor L2Y uniformly charged by the charging device L3 to form an electrostatic latent image. The electrostatic latent image is developed with yellow toner by the developing roller, becomes a visible image, and is electrostatically primary transferred onto the intermediate transfer body T that moves in synchronization with the photoreceptor L2Y by the transfer action of the primary transfer roller R1. Is done. Such latent image formation, development, and primary transfer operation are sequentially performed in a similar manner at the timings on the photosensitive members L2C, L2M, and L2K.
As a result, yellow, cyan, magenta, and black toner images are carried on the intermediate transfer member T as sequentially overlapping full-color toner images, and are moved in the direction of the arrow together with the intermediate transfer member T. At the same time, the paper P used for recording is fed out and transported from the paper cassette in the paper feeder L8 by the transport roller R2 for supplying the paper. The leading edge of the paper P takes the timing of the registration roller R3, and the registration roller R3 rotates to convey the paper P to the transfer area.

The full-color toner image on the intermediate transfer member T is transferred to the upper surface of the paper P that is conveyed in synchronization with the intermediate transfer member T by receiving a transfer action by the secondary transfer roller R5. The bias applied to the secondary transfer roller R5 has a positive polarity opposite to the toner charging polarity. It is also possible to apply a bias having the same polarity as the toner to the secondary transfer roller R5.
Thereafter, the surface of the intermediate transfer member T is cleaned by the cleaning device L9. The toner remaining on the surfaces of the photoreceptors L2Y, L2C, L2M, and L2K in the image forming unit L1 that has finished the primary transfer is a reverse polarity bias applied from the transparent electrode and light emitted from the light source through the transparent electrode. In response to this, the charge is injected and removed from the surface of each photoreceptor L2 by a recovery brush to which a bias having a polarity opposite to the injected charge is applied. The toner collected on the collection brush is discharged onto the photosensitive member L2 by applying a reverse bias to the collection to the brush at a fixed timing after the end of image formation, and is collected on the developing device L4 through the charging device L3. And reused. At this time, it is desirable that the charging device L3 is separated from the photoreceptor L2.
The paper P on which the toner image that has been superposed on the intermediate transfer member T is transferred is transferred to the fixing device L10. The toners of the respective colors superimposed on the paper P are subjected to the fixing action by the heat of the fixing device L10, and are melted and mixed to completely form a color image. In some cases, the control unit optimally controls the power used by the fixing device L10 in accordance with the image. Until the fixed toner is completely fixed on the paper, it is rubbed by a guide member or the like on the conveyance path, and an image may be lost or distorted. Thereafter, the paper is discharged onto the paper discharge stack portion by the paper discharge roller R4 with the image surface facing downward. In the paper discharge stack unit, the recorded matter of the subsequent pages is stacked so as to be sequentially stacked on top, so that the page order is aligned.

[First Embodiment]
FIG. 2 schematically shows a first embodiment of the driving force transmission device of the present invention.
As shown in FIG. 2, the driving force transmission device 1 includes a driving unit 2 and a driven unit 3. These units 2 and 3 are fixed to a product main body (not shown) by screwing or the like. The drive unit 2 transmits drive force generation means 21 such as an electric motor that generates drive force, a drive gear 22 that is rotationally driven by the drive force, and drive force from the drive force generation means 21 to the drive gear 22. And a drive shaft 23. In the first embodiment, a spur gear is used as the drive gear 22 and is fixed to the drive shaft 23. The driven unit 3 includes a driven gear 31 that meshes with the drive gear 22 and rotates, a driven shaft 32 that holds the driven gear 31, and a rotating body 33 that is fixed to the driven shaft 32.
Then, the driving force generated by the driving force generating means 21 is transmitted to the driving gear 22 via the driving shaft 23. Since the driven gear 31 meshes with the driving gear 22, the driving force is transmitted to the driven gear 31 and further transmitted to the rotating body 33 via the driven shaft 32.

The driving force transmission device 1 is applied to an image forming apparatus such as a copying machine, a printer, or a FAX. The rotating body 33 in this case serves as a developing roller. The driving force generating means 21 for generating the rotational driving force can set the rotation speed by an electric circuit (not shown) and can freely change the rotation speed.
The drive gear 22 and the driven gear 31 have a large number of teeth formed along the circumferential direction of the gear, and the number of teeth is arbitrarily determined for each gear. For example, the drive gear 22 can have 50 teeth and the driven gear 31 can have 100 teeth. In this case, when the drive gear 22 rotates twice, the driven gear 31 rotates once. In the first embodiment, the shape and size of the teeth of the drive gear 22 and the driven gear 31 are made equal in order to suitably mesh the gears.
FIG. 3 shows a state when the drive gear 22 and the driven gear 31 are engaged with each other. The drive gear 22 and the drive shaft 23 are concentric circles, and the driven gear 31 and the driven shaft 32 are also concentric circles. If it is not a concentric circle, a large load is applied to the shafts of both gears, resulting in rotational fluctuations. In FIG. 3, the center positions of the drive shaft 23 and the driven shaft 32 when the drive unit 2 is driven are point A and point B, respectively, and the angle between the line segment AB and the horizontal plane is α.

In order to receive the rotational driving force of the drive gear 22, the contact surface of the tooth of the driven gear 31 is ideally along the radial direction of the drive gear 22, but the shape of the gear teeth is as shown in FIG. The ideal driving force cannot be transmitted because of the pressure angle β. During actual rotation, as shown in FIG. 5, the driven gear 31 receives a force F in a direction inclined by an angle α-β with respect to the tangential direction of the circular gear. Further, the drive gear 22 receives a reaction force F ′.
Since force is applied to the drive gear 22 and the driven gear 31 in this way, force is also applied to the drive shaft 23 and the driven shaft 32. However, in this case, as shown in FIG. It is assumed that the force applied to 22 and 31 is applied to the shafts 23 and 32 as they are. Then, the position of the driven gear 31 at the time of rotational driving is deviated from the ideal position by the force F, so that the meshing state of the gear is shifted, it becomes difficult to transmit sufficient driving force, and factors such as vibration, noise, rotational fluctuation, etc. It becomes. In an image forming apparatus such as a copying machine, a printer, or a fax machine, the rotating body 33 corresponds to a developing roller, so that the shaft of the developing roller is inclined during rotation driving. As a result, the parallel relationship with the photosensitive member cannot be maintained, and a sufficient developing function cannot be exhibited, resulting in uneven density in the image.

  Therefore, in the present invention, when the drive unit 2 is driven, as shown in FIG. 7, the drive unit 2 is placed on a line inclined in the rotational direction of the driven shaft 32 by an angle α-β with respect to the perpendicular line AB. There is a center position of the driven shaft 32 when not driven. In this way, by moving the center position of the driven shaft 32 to the point C in advance, the center position of the driven shaft 32 moves to the optimum position, that is, the point B when the drive unit 2 is driven. , 31 can be meshed at an ideal position, the gear meshing accuracy is good, and driving force transmission can be achieved while suppressing vibration, noise, rotational fluctuation, and the like. Further, it is inexpensive because it is only necessary to change the position of the driven gear 31 in advance.

[Second Embodiment]
FIG. 8 schematically shows a second embodiment of the driving force transmission apparatus of the present invention.
The second embodiment is different from the first embodiment in that the drive shaft 23 of the drive unit 2 is fixed by a fixing member 24. As the fixing member 24, an L-shaped highly rigid member is used. For example, stainless steel or aluminum alloy can be used.
The long side surface of the L-shaped fixing member 24 is in contact with the end surface of the drive shaft 23 so that it does not deform even when a reaction force F ′ is applied to the drive shaft 23. Note that when the end surface of the drive shaft 23 is pressed, rotational driving is suppressed. Therefore, it is necessary to pay sufficient attention to the size of the fixing member 24 when it is assembled.
By adopting such a configuration, the deformation of the drive shaft 23 can be suppressed with a simple configuration, and vibration and rotational fluctuation can be suppressed.

[Third Embodiment]
FIG. 9 schematically shows a third embodiment of the driving force transmission apparatus of the present invention.
The third embodiment is different from the second embodiment in that the shape of the fixing member is different. In the second embodiment, the L-shaped fixing member 24 is used, but in the third embodiment, a rod-shaped fixing member 24A is attached so as to connect the bottom surface and the side surface of the drive unit 2 to form a truss structure. In addition, the inclination of the fixing member 24A is arranged along a direction inclined by an angle α-β with respect to the normal of the line segment AB.
With this arrangement, when the drive unit 2 is driven, the direction of the reaction force F ′ applied to the drive gear 22 and the longitudinal direction of the fixing member 24A are in the same direction, so that bending of the fixing member 24A can be suppressed. Thus, the shaft misalignment due to the influence of the reaction force F ′ can be reliably prevented. Note that various shapes such as square bars, round bars, and cylinders can be employed as the shape of the fixing member 24A.

[Fourth Embodiment]
FIG. 10 thru | or 13 is a figure for demonstrating 4th Embodiment of the driving force transmission apparatus of this invention.
The fourth embodiment differs from the first embodiment in that the shape of the gear is different. In the first embodiment, an example in which a spur gear is used as the drive gear 22 and the driven gear 31 has been described. However, a helical gear is used in the drive gear 22A and the driven gear 31A of the fourth embodiment. The helical gear has higher transmission efficiency than the spur gear, but since the teeth are arranged obliquely, a force along the thrust direction is generated, and the shaft and the gear may slide relative to each other.

FIG. 10 shows the direction of force generation when the helical gears are engaged. The helical tooth of the driven gear 31A has a twist angle of γ. Here, when the force applied to the tooth surface is Fa, a force of Fasinγ is applied to the gear in the thrust direction of the shaft by the twist angle γ. As shown in FIG. 11, a line segment AB connecting the point A that is the center position of the drive shaft 23 of the drive gear 22A and the point B that is the center position of the driven shaft 32 of the driven gear 31A is at an angle with respect to the horizontal plane. When it has an inclination of α, the meshing position of the driven gear 31A is below the driven shaft 32. FIG. 12 shows a state where the force Fasinγ in the axial thrust direction is applied to the driven gear 31A. The thrust force Fasinγ causes the driven gear 31A to be inclined at an angle λ with respect to the driven shaft 32, thereby preventing proper gear engagement. The inclination angle λ with respect to the driven shaft 32 is generated by a gap between the driven shaft 32 and the driven gear 31A.
Therefore, in the fourth embodiment, as shown in FIG. 13, the drive shaft 23 is fixed at an angle λ with respect to the drive unit 2.
With such a configuration, when the drive unit 2 is driven, the angular difference in the direction of teeth when the drive gear 22A and the driven gear 31A are engaged is eliminated, and vibration, noise, rotation fluctuation, and the like are suppressed.

[Fifth Embodiment]
FIG. 14 schematically shows a fifth embodiment of the driving force transmission apparatus of the present invention.
The fifth embodiment is different from the first embodiment in that a guide plate 25 is provided. The guide plate 25 is formed with a long hole 25a having a semicircular shape at both ends, and a driven shaft 32 is inserted into the long hole 25a.
The elongated hole 25a is movable between a point B that is the center position of the driven shaft 32 when the drive unit 2 is driven and a point C that is the center position of the driven shaft 32 when the drive unit 2 is not driven. Thus, the drive unit 2 is assembled so that the long hole 25a is arranged along the direction inclined by the angle α-β with respect to the perpendicular line of the line segment AB. Further, at the position of point B, the elongated hole 25a is formed so that the driven shaft 32 is restrained by one end of the elongated hole 25a.
The driven shaft 32 is constrained at one end of the long hole 25a so that the position of the driven shaft 32 does not deviate from a predetermined position by the force applied to the tooth surface of the driven gear 31 when the gear rotates. Can be reliably meshed at an ideal position, the gear meshing accuracy is good, and vibration, noise, rotation fluctuation, and the like are suppressed. Moreover, since the driven shaft 32 moves using the long hole 25a as a guide when the drive unit 2 is started, failure of the drive unit 2 can be prevented.

1 is a schematic diagram illustrating a configuration of an image forming apparatus of the present invention. It is the schematic which shows 1st Embodiment of the driving force transmission apparatus of this invention. It is the schematic which shows the state which the drive gear and the driven gear meshed | engaged. It is the schematic which shows the pressure angle of a drive gearwheel. It is the schematic which shows the force added to the gear at the time of meshing of a drive gear and a driven gear. It is the schematic which shows the force added to the shaft of the gear at the time of meshing with a drive gear and a driven gear. It is the schematic which shows the position of the drive shaft before and behind drive unit drive. It is the schematic which shows 2nd Embodiment of the driving force transmission apparatus of this invention. It is the schematic which shows 3rd Embodiment of the driving force transmission apparatus of this invention. It is a figure for demonstrating 4th Embodiment of the driving force transmission apparatus of this invention. It is a figure for demonstrating 4th Embodiment of the driving force transmission apparatus of this invention. It is a figure for demonstrating 4th Embodiment of the driving force transmission apparatus of this invention. It is the schematic which shows the principal part of 4th Embodiment of the driving force transmission apparatus of this invention. It is the schematic which shows the principal part of 5th Embodiment of the driving force transmission apparatus of this invention.

Explanation of symbols

L image forming apparatus L1 image forming unit L2 photoconductor L3 charging device L4 developing device L5 cleaning device L6 exposure device L7 toner cartridge L8 paper feeding device L9 cleaning device L10 fixing device P paper R1 transfer roller R2 transport roller R3 registration roller R4 paper discharge Roller R5 Secondary transfer roller R6 to R8 Roller 1 Driving force transmission device 2 Driving unit 21 Driving force generating means 22, 22A Driving gear 23 Driving shaft 24, 24A Fixing member 25 Guide plate 25a Slot 3 Driven unit 31, 31A Driven gear 32 Driven shaft 33 Rotating body

Claims (6)

A driving unit having driving force generating means for generating a driving force, a driving gear that is rotationally driven by the driving force, and a driving shaft that transmits the driving force from the driving force generating means to the driving gear;
A driven unit having a driven gear that meshes with the drive gear and is driven to rotate, a driven shaft that holds the driven gear, and a rotating body fixed to the driven shaft;
A driving force transmission device comprising:
When the drive shaft and the driven shaft are centered at points A and B, respectively, and the angle between the line segment AB and the horizontal plane is α and the pressure angle of the drive gear is β, The driving force transmitting device, wherein the center position of the driven shaft when the drive unit is not driven is on a line inclined in the rotation direction of the driven shaft by an angle α-β with respect to the perpendicular. The driving force transmission device according to claim 1,
A driving force transmission device comprising: a fixing member that fixes the driving shaft to the driving unit. The driving force transmission device according to claim 2,
The fixing member is disposed along a direction inclined by an angle α-β with respect to a perpendicular of the line segment AB. The driving force transmission device according to claim 1,
The drive gear and the driven gear are helical gears,
When the angular difference between the radial direction of the driven shaft and the radial direction of the driven gear when driving the drive unit is λ,
The drive force transmission device, wherein the drive shaft is fixed at an angle λ with respect to the drive unit. The driving force transmission device according to claim 1,
The drive unit is assembled so that the driven shaft is inserted into a long hole formed in the drive unit, and the long hole is disposed along a direction inclined by an angle α-β with respect to a perpendicular line of the line segment AB. ,
The driving force transmission device, wherein the center of the driven shaft coincides with the point B in a state where movement of the driven shaft is constrained at one end of the elongated hole when the drive unit is driven. An image forming apparatus comprising the driving force transmission device according to any one of claims 1 to 5.