JP4931469B2 - Driving device and image forming apparatus - Google Patents

Description

The present invention relates to a driving device and an image forming apparatus using the driving device.

  In an image forming apparatus such as a copying machine or a printer, it is necessary to mount each unit at a high density in response to a request for space saving or miniaturization. However, when high-density mounting is performed, it becomes difficult to properly heat each part by discharging heat generated by electronic components, frictional heat from the drive unit, or by appropriately circulating air. Therefore, as the size of the image forming apparatus is reduced, heat is accumulated in each unit, and the temperature rise increases, which may impair the reliability of the image forming apparatus.

  In particular, when the temperature rise of the gear in the drive unit increases, the distance between the shafts moves from the original position due to the linear expansion change of the gear, and the wear of the gear is promoted, or the efficiency of power interlocking is impaired. The reliability of the forming apparatus may be impaired.

  In order to verify such a defect, the inventor conducted the following experiment. This experiment is for grasping a change in drive transmission efficiency depending on load and temperature conditions in gear drive transmission. In the experiment, encoders were installed upstream and downstream in gear drive, and the follow-up of the amount of movement was evaluated. In the experiment, the gear temperature was set to 25 ° C. and 60 ° C., and no load was applied to the gear (load 0) and the state (load 6) applied to the gears on the driving side (upstream) and the driven side (downstream). This was done by measuring the amount of rotational movement. The result is shown in FIG.

  This experiment confirmed the following. When the load is light, the lower the temperature, the better the drive transmission efficiency. This is presumably because the resin gear expands when the temperature rises from room temperature and does not mesh at the correct meshing position. When the load is heavy, the drive transmission efficiency is almost the same regardless of temperature conditions. It was found that the load is more influential in this evaluation than the temperature condition. From the above, it was found that under the same load condition (when the load is light in this experiment), the drive transmission deteriorates due to the temperature rise, and this confirmed the effectiveness of cooling the gear.

  Patent Document 1 describes that an expansion member is provided in order to change the distance between gear shafts according to temperature. In Patent Document 1, the thermal expansion coefficient of the expansion member is such that the change in the tooth surface backlash based on the change caused by heat between the shafts is caused by the sliding of the gears in the axial direction based on the thermal expansion coefficient of the expansion member. The helical gear teeth effect is selected to be compensated for.

Japanese Patent Application Laid-Open No. H10-228561 describes an apparatus in which an input duct and an output duct are formed in a gear case, an air flow path is formed in the gear case, and the rotary sliding portion can be cooled.

  Japanese Patent Application Laid-Open No. H10-260260 describes a heat pipe that efficiently cools the inside of a housing in which a drive device is built.

  In Patent Document 4, in order to keep the distance between the shafts uniform, the distance between the shafts of the large-diameter and small-module resin gear and the motor gear meshing therewith is determined by a pitch circle circle that is substantially the same as the pitch circle diameter. The motor gear is configured to be pressed against the large-diameter and small-module resin gear with a spring to absorb the variation in the distance between the shafts due to the temperature change.

Special table 2003-503650 gazette JP-A-2005-090574 JP 2000-162841 A JP 2005-258316 A

  By the way, in the thing of the patent document 1 mentioned above, various members are added to a drive device, and a number of parts will increase or cost will be increased. Moreover, in the thing of patent document 2, since a gear and a shaft member are not actively cooled only by forming the air flow path in a gear case, a shaft member cannot be cooled efficiently. Moreover, the thing of patent document 3 provides a heat pipe in a housing | casing, and requires a special component and there exists a problem that cost increases. And the thing of patent document 4 does not cool a gear, and does not reach the fundamental solution of not raising the temperature of a gear.

  In view of the above-described conventional problems, an object of the present invention is to provide a drive device that can effectively prevent a temperature increase of a gear and a shaft member without increasing the number of components.

The invention of claim 1
A drive device comprising a shaft member and a gear rotatably disposed on the shaft member,
The rewritable form the shaft member integrally with the face plate member in the drive device,
The shaft member has a flow path through which gas can flow,
The flow path passes through the shaft member along the axis of the shaft member,
The outer diameter of the portion other than the contact portion with the gear of the shaft member is formed as a large diameter portion larger than the outer diameter of the contact portion,
The large diameter portion is tapered.
This is a drive device characterized by that.

The invention of claim 2
A drive device comprising a shaft member and a gear rotatably disposed on the shaft member,
While forming the shaft member integrally with the face plate member in the drive device,
The shaft member has a flow path through which gas can flow,
The flow path extends through the shaft member along the axis of the shaft member,
The outer diameter of the portion other than the contact portion with the gear of the shaft member is formed as a large diameter portion larger than the outer diameter of the contact portion,
In the large diameter portion, on the outside of the flow path along the axis, a plurality of communication paths that communicate the flow path with the outside are formed.
This is a drive device characterized by that.

According to a third aspect of the present invention, in the drive device according to the first or second aspect , the material of the shaft member is a metal .

According to a fourth aspect of the present invention, in the driving device according to the first or second aspect , the material of the shaft member is a synthetic resin.

According to a fifth aspect of the present invention, in the drive device according to any one of the first to fourth aspects, a standing portion of the shaft member on the face plate member is disposed in the vicinity of the device including a fan. .

According to a sixth aspect of the present invention, in the drive device according to any one of the first to fourth aspects, the tip end portion of the shaft member is disposed in the vicinity of a device including a fan .

According to a seventh aspect of the present invention, in the driving device according to any one of the first to sixth aspects, a portion where the shaft member is erected on the face plate member is disposed in the vicinity of the one device including the fan, and the fan The distal end portion of the shaft member is disposed in the vicinity of another device including

According to an eighth aspect of the present invention, there is provided an image forming apparatus comprising the driving apparatus according to any one of the first to sixth aspects .

According to the present invention, the inner area of the flow passage is increased by the large-diameter portion provided in the flow path passing through the shaft member, to improve the cooling of the by that the shaft member and the gear on the air flow through the flow passage, In addition, the surface area of the shaft member is increased to improve heat dissipation, and the airflow easily flows into the flow path of the shaft member, thereby suppressing the temperature rise of the gear and changing the meshing position of the gear in the driving device. This can improve the durability of the gear and the reliability of the drive device and thus the image forming apparatus equipped with this drive device.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  Embodiments of the drive device according to the present invention will be described below. The drive device according to this example is used for a drive unit of an image forming apparatus. FIG. 1 and FIG. 2 are perspective views showing the configuration of the driving apparatus according to the embodiment.

  The drive device 1 according to this example drives a drive gear 6 by a motor 3 fixed to a bracket 7 attached to a plate member 2, and rotates a driven gear 4 that meshes with the drive gear 6, as a unit. It is configured. In this example, the driven gear 4 is rotatably fitted to the shaft member 5 and meshes with another gear 8 to transmit power. In this example, the shaft member 5 is fixedly disposed on the bracket 2 without rotating when the driven gear 4 rotates.

  In the present invention, the gear is cooled by providing a flow path of the air flow in the shaft member of the drive device having such a configuration, the temperature rise of the gear is suppressed, the target meshing position is maintained, and the durability of the gear is maintained. And the reliability of the image forming apparatus can be improved. The configuration of the drive device 1 is the same in each embodiment described below, and the description of the overall configuration of the drive device 1 is omitted in the description of each embodiment.

Hereinafter, the configuration of the driving apparatus according to the embodiment will be described in detail. FIG. 3 is a cross-sectional view showing the configuration of the driving apparatus according to the first embodiment. In the driving apparatus 10 according to this example, the shaft member 12 is erected integrally with the plate member 11. Further, the driven gear 4 described above is held on the shaft member 12 so as to be rotatable. The plate member 11 and the shaft member 12 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 12 is formed with a flow path 13 penetrating along the axis of the shaft member 12, and the air flow a flows through the flow path 13. With this configuration, the shaft member 12 is cooled by the airflow a, and the heat of the driven gear 4 held in contact with the shaft member 12 is also conducted to the shaft member 12 and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIG. 4 is a front view showing the configuration of the driving apparatus according to the second embodiment. In the driving device 20 according to the present example, the shaft member 22 is formed integrally with the plate member 21 or is fixedly erected on the plate member 21. Further, the driven gear 4 described above is held on the shaft member 22 so as to be rotatable. The plate member 21 and the shaft member 22 can be formed of metal or synthetic resin, respectively.

  In this example, a groove-like flow path 23 along the axis is formed on the outer peripheral portion of the shaft member 22, and a groove-shaped annular flow path 24 is formed on the contact portion with the driven gear 4. Yes. In this example, the air flow b flows through the flow path 23 and the air flow c flows through the annular flow path 24. With this configuration, the shaft member 22 and the driven gear 4 are cooled by the air flow b and the air flow c, and the heat of the driven gear 4 is conducted to the shaft member 22 side and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the gear and the reliability of the image forming apparatus can be improved.

  FIG. 5 is a front view showing the configuration of the driving apparatus according to the third embodiment. In the driving device 30 according to the present example, the shaft member 32 is formed integrally with the plate member 31 or is fixedly erected on the plate member 31. The shaft member 32 holds the driven gear 4 described above in a rotatable manner. The plate member 31 and the shaft member 32 can be formed of metal or synthetic resin, respectively.

  In this example, a spiral groove-like flow path 33 along the outer periphery is formed on the outer peripheral portion of the shaft member 32. The flow path 33 is also provided at a contact portion with the driven gear 4. In this example, the air flow d is configured to flow through the flow path 33. With this configuration, the shaft member 32 and the driven gear 4 are cooled by the air flow d, and the heat of the driven gear 4 is conducted to the shaft member 32 side and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the gear and the reliability of the image forming apparatus can be improved.

  FIG. 6 is a cross-sectional view showing the configuration of the driving apparatus according to the fourth embodiment. In the driving device 40 according to the present example, the shaft member 42 is formed integrally with the plate member 41 or is fixedly erected on the plate member 41. Further, the driven gear 4 described above is held on the shaft member 42 so as to be rotatable. The plate member 41 and the shaft member 42 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 42 is formed with a flow path 43 penetrating along the axis of the shaft member 42, and the air flow e flows through the flow path 13. In this example, a communication hole 44 communicating with the flow path 43 and communicating with the contact portion of the driven gear 4 on the outer periphery of the shaft member is formed. With this configuration, the shaft member 42 is cooled by the air flow e, and the heat of the driven gear 4 held in contact with the shaft member 42 is also transferred to the shaft member 42 and cooled, and the heat of the driven gear 4 communicates. The driven gear 4 flows into the flow path 43 through the hole 44 and is cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIG. 7 is a cross-sectional view showing the configuration of the driving apparatus according to the fifth embodiment. In the driving device 50 according to this example, the shaft member 52 is formed integrally with the plate member 51 or is fixedly erected on the plate member 51. Further, the driven gear 4 described above is held on the shaft member 52 so as to be rotatable. The plate member 51 and the shaft member 52 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 52 is formed with a flow path 53 penetrating along the axis of the shaft member 52, and the air flow f flows through the flow path 53. Further, in this example, a communication hole 54 that communicates with the flow path 53 and communicates with a portion of the outer periphery of the shaft member that is attached to the plate member 51 from the driven gear 4 is formed. The air flow g is configured to circulate and hit the driven gear 4. With this configuration, the shaft member 52 is cooled by the air flow f, and the heat of the driven gear 4 held in contact with the shaft member 52 is also transferred to the shaft member 52 to be cooled. The airflow g from the communication hole 54 is hit and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIG. 8 is a front view showing the configuration of the driving apparatus according to the sixth embodiment. In the driving device 60 according to this example, the shaft member 62 is formed integrally with the plate member 61 or is erected and fixed to the plate member 61. Further, the driven gear 4 described above is held on the shaft member 62 so as to be rotatable. The plate member 61 and the shaft member 62 can be formed of metal or synthetic resin, respectively.

In this example, the shaft member 62 is formed with a plurality of groove-shaped annular flow paths 63 along the outer periphery on the plate member 61 side from the portion around which the driven gear 4 is attached. The annular channel 63 can be formed by cutting, knurling or the like. According to this example, the shaft member 62 flows in the annular flow path 63 and cools the shaft member 62, and the surface area of the shaft member 62 increases to be easily cooled, and is held in contact with the shaft member 62. The heat of the driven gear 4 is also conducted to the shaft member 62 and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved. In addition, this annular flow path 63 can be attached to the shaft member of Examples other than a present Example.

  FIG. 9 is a front view showing the configuration of the driving apparatus according to the sixth embodiment. In the driving device 70 according to this example, the shaft member 72 is formed integrally with the plate member 71 or is fixedly erected on the plate member 71. Further, the driven gear 4 described above is held on the shaft member 72 so as to be rotatable. The plate member 71 and the shaft member 72 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 72 is provided with a plurality of cooling fins 73 on the plate member 71 side around the periphery of the shaft member 72 where the driven gear 4 is attached. The fins 73 are preferably formed of a metal having good thermal conductivity, such as aluminum. According to this example, the heat of the shaft member 72 is radiated from the fins 73 and cooled, and the heat of the driven gear 4 held in contact with the shaft member 72 is also conducted to the shaft member 72 and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved. In addition, this fin 73 can be attached to the shaft member of Examples other than a present Example.

  FIG. 10 is a front view showing the configuration of the driving apparatus according to the eighth embodiment. In the driving device 80 according to this example, the shaft member 82 is formed integrally with the plate member 81 or is fixedly erected on the plate member 81. Further, the driven gear 4 described above is held on the shaft member 82 so as to be rotatable. The plate member 81 and the shaft member 82 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 82 is provided with a groove-like flow path 83 along the bus line on the outer periphery thereof on the plate member 81 side from the portion around which the driven gear 4 is attached. The channel 83 can be formed by cutting, knurling, or the like. According to this example, the shaft member 82 flows through the flow path 83 and the shaft member 82 is cooled. Further, the surface area of the shaft member 82 is increased in the flow path 83 and is easily cooled, and the heat of the driven gear 4 held in contact with the shaft member 82 is also conducted to the shaft member 82 and cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved. Moreover, when the flow path 83 is formed by knurling, the cost of manufacturing the shaft member 82 can be reduced. In addition, this flow path 83 can be attached to the shaft member of Examples other than a present Example.

  FIG. 11 is a cross-sectional view showing the configuration of the driving apparatus according to the ninth embodiment. In the driving device 90 according to this example, the shaft member 92 is formed integrally with the plate member 91 and is erected. Further, the driven gear 4 described above is held on the shaft member 92 so as to be rotatable. The plate member 91 and the shaft member 92 can be formed of metal or synthetic resin.

  In this example, the shaft member 92 is provided with a large-diameter portion 94 at the attachment portion with the plate member 91, and a channel 93 penetrating along the axis of the shaft member 92 is formed. The air flow h is configured to circulate. In this example, the diameter of the flow path on the side of the plate member 91 is also increased in accordance with the large diameter portion 94. For this reason, the internal area of the flow path 93 becomes large and the cooling property by the airflow h improves. In this example, by providing the large-diameter portion 94, the surface area of the shaft member 92 is increased to improve heat dissipation, and the area of the opening 95 through which the airflow enters the flow path 93 of the shaft member 92 is increased to increase the airflow. Makes it easier to flow in.

  With this configuration, the shaft member 92 is cooled by the airflow, the heat of the driven gear 4 held in contact with the shaft member 92 is also transferred to the shaft member 92 and cooled, and the driven gear 4 is cooled. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIG. 12 is a cross-sectional view showing the configuration of the driving apparatus according to the tenth embodiment. In the driving apparatus 100 according to the present example, the shaft member 102 is integrally formed with the plate member 101 and is erected. Further, the driven gear 4 described above is held on the shaft member 102 so as to be rotatable. The plate member 101 and the shaft member 102 can be formed of metal or synthetic resin.

  In this example, the shaft member 102 is provided with a tapered large-diameter portion 104 that expands toward the 101 side at the attachment portion with the plate member 101, and a flow path 103 that penetrates along the axis of the shaft member 102. The air flow i is formed to flow through the flow path 103. In this example, it is set as the taper shape which the shaft member 102 side of the flow path 103 expands. For this reason, the inner area of the flow path 103 becomes large and the cooling property by the airflow i improves. Further, in this example, by providing the large diameter portion 104, the surface area of the shaft member 102 is increased to improve heat dissipation, and the area of the opening 105 through which the airflow i enters the flow path 103 of the shaft member 102 is increased. This makes it easier for airflow to flow in.

  With this configuration, the shaft member 102 is cooled by the airflow i, the heat of the driven gear 4 held in contact with the shaft member 102 is also transmitted to the shaft member 102 and cooled, and the temperature increase of the driven gear 4 is suppressed. The meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIGS. 13A and 13B are diagrams showing the configuration of the driving apparatus according to the eleventh embodiment, in which FIG. 13A is a cross-sectional view, and FIG. 13B is an end view corresponding to the line BB in FIG. In the driving device 110 according to this example, the shaft member 112 is formed integrally with the plate member 111 and is erected. The shaft member 112 holds the driven gear 4 described above in a rotatable manner. The plate member 111 and the shaft member 112 can be formed of metal or synthetic resin.

  In this example, the shaft member 112 is provided with a large-diameter portion 114 at the attachment portion with the plate member 111, and a channel 113 penetrating along the axis of the shaft member 112 is formed. Has a through-hole portion 115 communicating with both sides of the plate member 111. In this example, in addition to the air flow j flowing in the flow path 113, the air flow k flows from the through hole 115 in the large diameter portion 114 so as to hit the driven gear 4. In this example, the surface area of the shaft member 112 is increased by the large-diameter portion 114 to improve heat dissipation, and the area of the opening 116 into which the airflow enters the flow path 113 of the shaft member 112 is increased to further increase the airflow j. It is easy to flow in.

  With this configuration, the shaft member 112 is cooled by the airflow j, and the driven gear 4 held in contact with the shaft member 92 is also cooled by conduction of heat to the shaft member 112. Cooled by the air flow k from the section 115. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.

  FIG. 14 is a cross-sectional view showing the configuration of the driving apparatus according to the twelfth embodiment. The drive device 120 according to this example is disposed between the device 131 and the device 133. The device 131 includes a fan 132, and the device 133 includes a fan 134. Both the fans 132 and 134 blow air from the device 131 toward the device 133. In this example, the shaft member 122 is erected integrally with the plate member 121 or fixed to the plate member 121. The shaft member 122 extends between the devices 131 and 133, and the driven gear 4 described above is rotatably held on the shaft member 112. The plate member 111 and the shaft member 112 can be formed of metal or synthetic resin, respectively.

  In this example, the shaft member 122 is formed with a flow path 123 penetrating along the axis of the shaft member 122. In this example, the air flow m by the both fans 132 and 134 flows through the flow path 123.

With this configuration, the shaft member 122 is cooled by the air flow m generated by both fans, and the driven gear 4 held in contact with the shaft member 122 is also cooled by conduction of heat to the shaft member 122. As a result, the temperature rise of the driven gear 4 can be suppressed, the meshing position of the driven gear 4 can be maintained, and the durability of the driven gear 4 and the reliability of the image forming apparatus can be improved.
In the above example, the case where the fan of the device is arranged on both sides of the driving device 120 is shown, but the fan may be arranged only on one side of the driving device 120. Further, instead of the driving device 120, the driving devices according to the first to eleventh embodiments can be arranged.

It is a perspective view which shows the structure of the drive device which concerns on an Example. It is a perspective view which shows the structure of the drive device shown in FIG. It is sectional drawing which shows the structure of the drive device which concerns on a 1st Example. It is a front view which shows the structure of the drive device which concerns on a 2nd Example. It is a front view which shows the structure of the drive device which concerns on a 3rd Example. It is sectional drawing which shows the structure of the drive device which concerns on a 4th Example. It is sectional drawing which shows the structure of the drive device which concerns on a 5th Example. It is a front view which shows the structure of the drive device which concerns on a 6th Example. It is sectional drawing which shows the structure of the drive device which concerns on a 7th Example. It is a front view which shows the structure of the drive device which concerns on an 8th Example. It is sectional drawing which shows the structure of the drive device which concerns on a 9th Example. It is sectional drawing which shows the structure of the drive device which concerns on a 10th Example. It is a figure which shows the structure of the drive device which concerns on an 11th Example, (a) is sectional drawing, (b) is an end elevation corresponding to the BB line in (a). It is sectional drawing which shows the structure of the drive device which concerns on a 12th Example. It is a graph which shows the change of the drive transmission efficiency by the conditions of the load and temperature in the gear drive transmission of a drive device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Drive device 2 ... Plate member 3 ... Motor 4 ... Driven gear 5 ... Shaft member 6 ... Drive gear 7 ... Bracket 8 ... Gear 10 ... Drive Device 11 ... plate member 12 ... shaft member 13 ... channel 20 ... drive device 21 ... plate member 22 ... shaft member 23 ... channel 24 ... annular channel 30 ... Driving device 31 ... Plate member 32 ... Shaft member 33 ... Channel 40 ... Driving device 41 ... Plate member 42 ... Shaft member 43 ... Channel 44 ..Communication hole 50 ... Drive device 51 ... Plate member 52 ... Shaft member 53 ... Flow path 54 ... Communication hole 60 ... Drive device 61 ... Plate member 62 ... Shaft member 63 ... annular flow path 70 ... drive device 71 ... plate member 72 ... shaft member 73 ... fin 80 ... drive device 81 ... plate member 82 ... Shaft member 83... Channel 90... Drive device 91... Plate member 92... Shaft member 93. 101 ... plate member 102 ... shaft member 103 ... channel 104 ... large diameter portion 105 ... opening 110 ... drive device 111 ... plate member 112 ... shaft member 113 ··· Channel 114 ··· Large diameter portion 115 ··· Through-hole portion 116 ··· Opening 120 ··· Drive device 121 ··· Plate member 122 ··· Shaft member 123 ··· Channel 131 ··· -Device 132 ... Fan 133 ... Device 134 ... Fan

Claims (8)

A drive device comprising a shaft member and a gear rotatably disposed on the shaft member,
The rewritable form the shaft member integrally with the face plate member in the drive device,
The shaft member has a flow path through which gas can flow,
The flow path passes through the shaft member along the axis of the shaft member,
The outer diameter of the portion other than the contact portion with the gear of the shaft member is formed as a large diameter portion larger than the outer diameter of the contact portion,
The large diameter portion is tapered.
A drive device characterized by that. A drive device comprising a shaft member and a gear rotatably disposed on the shaft member,
While forming the shaft member integrally with the face plate member in the drive device,
The shaft member has a flow path through which gas can flow,
The flow path extends through the shaft member along the axis of the shaft member,
The outer diameter of the portion other than the contact portion with the gear of the shaft member is formed as a large diameter portion larger than the outer diameter of the contact portion,
In the large diameter portion, on the outside of the flow path along the axis, a plurality of communication paths that communicate the flow path with the outside are formed.
A drive device characterized by that. Drive device according to claim 1 or 2, characterized in that the material of the shaft member and the metal. Drive device according to claim 1 or 2, characterized in that the material of the shaft member and a synthetic resin. The drive device according to any one of claims 1 to 4, wherein a standing portion of the shaft member on the face plate member is disposed in the vicinity of the device including a fan . Driving device according to any one of claims 1, characterized in that the front end portion of the shaft member in the vicinity of the device provided with a fan placed 4. A portion where the shaft member is erected on the face plate member is disposed in the vicinity of one device having a fan, and a tip portion of the shaft member is disposed in the vicinity of another device having a fan. The drive device according to any one of claims 1 to 6. An image forming apparatus characterized by comprising using a driving device according to any one of 請 Motomeko 1 to 6.