【特許請求の範囲】
【請求項１】 駆動歯車と、
前記駆動歯車に従動して噛み合う中間歯車と、
前記中間歯車に従動して噛み合う従動歯車と、
前記中間歯車の回転中心を中心とした円筒状のスリーブと、
前記従動歯車が回転可能に軸支され、前記従動歯車の回転軸と平行な軸を中心に回動可能に支持され、回動方向に直角な面で形成された、前記スリーブと当接可能な当接部位を有するレバー部材と、
を含む少なくとも３つ以上の歯車が噛み合って歯車列を構成している歯車伝達機構において、
歯車が駆動伝達状態で前記レバー部材の当接部位と前記スリーブとが当接することによって前記レバー部材の位置が決定され、前記駆動歯車の中心と前記中間歯車の中心を結ぶ直線と、前記従動歯車の中心と前記中間歯車の中心を結ぶ直線とのなす角度が前記中間歯車の１歯ピッチ角のほぼ整数倍となっていることを特徴とする歯車伝達機構。
【請求項２】 駆動歯車と、
前記駆動歯車に従動して噛み合う入力歯車とこの入力歯車と同一歯数の出力歯車とが同軸的に固定された中間歯車と、
前記中間歯車の出力歯車に従動して噛み合う従動歯車と、
前記中間歯車の回転中心を中心とした円筒状のスリーブと、
前記従動歯車が回転可能に軸支され、前記従動歯車の回転軸と平行な軸を中心に回動可能に支持され、回動方向に直角な面で形成された、前記スリーブと当接可能な当接部位を有するレバー部材と、を含む少なくとも３つ以上の歯車が噛み合って歯車列を構成している歯車伝達機構において、
歯車が駆動伝達状態で前記レバー部材の当接部位と前記スリーブとが当接することによって前記レバー部材の位置が決定され、前記駆動歯車の中心と前記中間歯車の中心を結ぶ直線と、前記従動歯車の中心と前記中間歯車の中心を結ぶ直線とのなす角度が、前記中間歯車の１歯ピッチ角のほぼ整数倍と前記中間歯車の入力歯車と出力歯車の歯のずれ角度との和にほぼ等しくなっていることを特徴とする歯車伝達機構。
【請求項３】 前記中間歯車の入力歯車と出力歯車が同一軸上に相対的な角度を固定された２つの歯車である、請求項２に記載の歯車伝達機構。
【請求項４】 記録媒体と、回転駆動される記録媒体搬送手段と、前記記録媒体上に画像を形成する画像形成手段を有する画像形成装置において、
前記記録媒体搬送手段の回転駆動伝達に請求項１又は２に記載の歯車伝達機構を用いたことを特徴とする画像形成装置。
[Claims]
1. The drive gear and
An intermediate gear that drives and meshes with the drive gear,
A driven gear that drives and meshes with the intermediate gear,
A cylindrical sleeve centered on the center of rotation of the intermediate gear and
The driven gear is rotatably supported by an axis, is rotatably supported around an axis parallel to the rotating axis of the driven gear, and can come into contact with the sleeve formed on a surface perpendicular to the rotation direction. A lever member having a contact part and
In a gear transmission mechanism in which at least three or more gears including the above are meshed to form a gear train.
The position of the lever member is determined by the contact portion of the lever member and the sleeve in the drive transmission state of the gear, the straight line connecting the center of the drive gear and the center of the intermediate gear, and the driven gear. A gear transmission mechanism characterized in that the angle formed by a straight line connecting the center of the intermediate gear and the center of the intermediate gear is approximately an integral multiple of the one-tooth pitch angle of the intermediate gear.
2. The drive gear and
An intermediate gear in which an input gear that is driven by the drive gear and meshes with the input gear and an output gear having the same number of teeth as the input gear are coaxially fixed.
A driven gear that drives and meshes with the output gear of the intermediate gear,
A cylindrical sleeve centered on the center of rotation of the intermediate gear and
The driven gear is rotatably supported by an axis, is rotatably supported around an axis parallel to the rotating axis of the driven gear, and can come into contact with the sleeve formed on a surface perpendicular to the rotation direction. In a gear transmission mechanism in which a lever member having a contact portion and at least three or more gears including the lever member mesh with each other to form a gear train.
The position of the lever member is determined by the contact portion of the lever member and the sleeve in the drive transmission state of the gear, the straight line connecting the center of the drive gear and the center of the intermediate gear, and the driven gear. The angle formed by the straight line connecting the center of the intermediate gear and the center of the intermediate gear is approximately equal to the sum of approximately an integral multiple of the one-tooth pitch angle of the intermediate gear and the misalignment angle of the input gear and the tooth of the output gear of the intermediate gear. A gear transmission mechanism characterized by being
3. The gear transmission mechanism according to claim 2, wherein the input gear and the output gear of the intermediate gear are two gears in which the relative angles are fixed on the same axis.
4. In an image forming apparatus having a recording medium, a rotation-driven recording medium conveying means, and an image forming means for forming an image on the recording medium.
An image forming apparatus according to claim 1 or 2 , wherein the gear transmission mechanism according to claim 1 or 2 is used for the rotational drive transmission of the recording medium conveying means.
【０００２】
【従来の技術】
駆動側の歯車とそれに従動する従動側の歯車の噛み合い部分では、駆動側の歯車の歯と従動側の歯の噛み合いが連続的に繰り返されており、同時に噛み合っている歯の対数や噛み合いの状態は歯車の回転の進行とともに周期的に変化している。一般に、刻々変化する同時に噛み合っている歯の数の時間平均をその歯車対の噛み合い率と呼び、噛み合い率の高い歯車対ほど角速度変動、振動、騒音等が少ないとされている。このような歯車対の集合である歯車伝達機構は画像形成装置の動力伝達機構をはじめとして多方面に利用されており、負荷変動による角速度変動、振動、騒音等を低減するさまざまな工夫がなされている。従来の歯車伝達装置の一例では、歯車又は駆動源によって回転駆動された駆動歯車と、回動可能に支持されたレバーに回転可能に軸支された従動歯車と、駆動歯車と従動歯車との間に配置された中間歯車とを備えている。そして、駆動歯車から中間歯車へ、中間歯車から従動歯車へと順次回転駆動が伝達される。中間歯車と従動歯車にはそれぞれ図示されていない歯車、カム、プーリ、ローラ等の機能部品が連結しており、中間歯車と従動歯車はそれらの機械的負荷に抗して回転する構成になっている。この機械的負荷は常に一定ではなく、部品の寸法ばらつきや取り付けばらつき、動作時の機械的な振動や外乱等の影響によって変動が生じ、この負荷変動が歯車の等速回転を乱し、角速度変動を発生させる原因となる。ここで、このような歯車伝達機構の特徴として、従動歯車やその他の歯車に比べて中間歯車の角速度の等速精度が最も要求されるという点であり、言い換えれば従動歯車の負荷変動の影響を中間歯車に伝播することなく、中間歯車を可能な限り駆動歯車の等速回転に忠実に従動回転させることが要求されているということである。
0002.
[Conventional technology]
In the meshing part of the drive side gear and the driven side gear that follows it, the teeth of the drive side gear and the meshing of the driven side teeth are continuously repeated, and at the same time, the logarithm of the meshing teeth and the state of meshing. Changes periodically as the rotation of the gear progresses. Generally, the time average of the number of teeth that are meshing at the same time, which changes every moment, is called the meshing ratio of the gear pair, and it is said that the gear pair having a higher meshing ratio has less angular velocity fluctuation, vibration, noise, and the like. The gear transmission mechanism, which is a set of such gear pairs, is used in various fields including the power transmission mechanism of the image forming device, and various measures have been taken to reduce angular velocity fluctuations, vibrations, noises, etc. due to load fluctuations. There is. In an example of a conventional gear transmission device, between a drive gear that is rotationally driven by a gear or a drive source, a driven gear that is rotatably supported by a lever that is rotatably supported, and between the drive gear and the driven gear. It is equipped with an intermediate gear arranged in. Then, from the drive gear to the intermediate gear, sequential rotation driving force is transmitted from the intermediate gear to the driven gear. Functional parts such as gears, cams, pulleys, and rollers (not shown) are connected to the intermediate gear and the driven gear , respectively, and the intermediate gear and the driven gear are configured to rotate against their mechanical load. There is. This mechanical load is not always constant, and fluctuates due to the effects of component dimensional variation, mounting variation, mechanical vibration during operation, disturbance, etc., and this load fluctuation disturbs the constant velocity rotation of the gear, resulting in angular velocity fluctuation. Causes the occurrence of. Here, a feature of such a gear transmission mechanism is that the constant velocity accuracy of the angular velocity of the intermediate gear is most required as compared with the driven gear and other gears, in other words, the influence of the load fluctuation of the driven gear. without propagating to the intermediate gear is that it is faithfully rotated by the uniform rotation of as long as the drive gear possible intermediate gear is required.
【０００４】
【課題を解決するための手段】
上記目的を達成するために本発明の歯車伝達機構では、駆動歯車と、前記駆動歯車に従動して噛み合う中間歯車と、前記中間歯車に従動して噛み合う従動歯車と、前記中間歯車の回転中心を中心とした円筒状のスリーブと、前記従動歯車が回転可能に軸支され、前記従動歯車の回転軸と平行な軸を中心に回動可能に支持され、回動方向に直角な面で形成された前記当接部材と当接可能な当接部位を有するレバー部材と、を含む少なくとも３つ以上の歯車が噛み合って歯車列を構成している歯車伝達機構において、歯車が駆動伝達状態で前記レバー部材の当接部位と前記スリーブとが当接することによって前記レバー部材の位置が決定され、前記駆動歯車の中心と前記中間歯車の中心を結ぶ直線と、前記従動歯車の中心と前記中間歯車の中心を結ぶ直線とのなす角度が前記中間歯車の１歯ピッチ角のほぼ整数倍となっていることを特徴とする。
0004
[Means for solving problems]
In order to achieve the above object, in the gear transmission mechanism of the present invention, the drive gear, the intermediate gear that is driven and meshed with the drive gear, the driven gear that is driven and meshed with the intermediate gear, and the rotation center of the intermediate gear are A cylindrical sleeve at the center and the driven gear are rotatably supported, supported rotatably around an axis parallel to the rotation axis of the driven gear, and formed on a surface perpendicular to the rotation direction. In a gear transmission mechanism in which at least three or more gears including a contact member and a lever member having a contact portion capable of contacting the contact member are meshed with each other to form a gear train, the lever is in a drive transmission state. The position of the lever member is determined by the contact portion of the member and the sleeve , the straight line connecting the center of the drive gear and the center of the intermediate gear, the center of the driven gear, and the center of the intermediate gear. The angle formed by the straight line connecting the two gears is approximately an integral multiple of the one-tooth pitch angle of the intermediate gear.
上記目的を達成するために本発明の歯車伝達機構では、駆動歯車と、前記駆動歯車に従動して噛み合う入力歯車とこの入力歯車と同一歯数の出力歯車とが同軸的に固定された中間歯車と、前記中間歯車の出力歯車に従動して噛み合う従動歯車と、前記中間歯車の回転中心を中心とした円筒状のスリーブと、前記従動歯車が回転可能に軸支され、前記従動歯車の回転軸と平行な軸を中心に回動可能に支持され、回動方向に直角な面で形成された、前記スリーブと当接可能な当接部位を有するレバー部材と、を含む少なくとも３つ以上の歯車が噛み合って歯車列を構成している歯車伝達機構において、歯車が駆動伝達状態で前記レバー部材の当接部位と前記スリーブとが当接することによって前記レバー部材の位置が決定され、前記駆動歯車の中心と前記中間歯車の中心を結ぶ直線と、前記従動歯車の中心と前記中間歯車の中心を結ぶ直線とのなす角度が、前記中間歯車の１歯ピッチ角のほぼ整数倍と前記中間歯車の入力歯車と出力歯車の歯のずれ角度との和にほぼ等しくなっていることを特徴とする。
In order to achieve the above object, in the gear transmission mechanism of the present invention, an intermediate gear in which a drive gear, an input gear that is driven and meshed with the drive gear, and an output gear having the same number of teeth as the input gear are coaxially fixed. The driven gear that meshes with the output gear of the intermediate gear, the cylindrical sleeve centered on the center of rotation of the intermediate gear, and the driven gear are rotatably supported by the rotating shaft of the driven gear. At least three or more gears including a lever member rotatably supported around an axis parallel to the sleeve and formed on a surface perpendicular to the direction of rotation and having a contact portion capable of contacting the sleeve. In the gear transmission mechanism that meshes with each other to form a gear train, the position of the lever member is determined by the contact portion of the lever member and the sleeve in contact with the gear in the drive transmission state, and the position of the lever member is determined. The angle formed by the straight line connecting the center and the center of the intermediate gear and the straight line connecting the center of the driven gear and the center of the intermediate gear is approximately an integral multiple of the one-tooth pitch angle of the intermediate gear and the input of the intermediate gear. It is characterized in that it is almost equal to the sum of the deviation angles of the gears and the teeth of the output gear.
【００２５】
【発明の効果】
以上説明したように、本発明によれば、少なくとも３つ以上の歯車が連続した歯車伝達機構において、最も精度の要求される歯車を中間歯車、その前後２つの歯車をそれぞれ駆動歯車、従動歯車としたとき、駆動歯車と中間歯車の噛み合い部の状態と、従動歯車と中間歯車の噛み合い部の状態を常に一致させるような構成をとることによって、従動歯車と中間歯車の噛み合い率が最も高く、従動歯車の負荷変動による外乱が中間歯車に最も伝播しやすい状態において、駆動歯車と中間歯車の噛み合い率も又同時に最も高い状態になる。このため、中間歯車が駆動歯車に最も強く拘束され等速回転が伝達しやすく、中間歯車は従動歯車の負荷変動による影響を受けにくくなり、中間歯車の角速度変動は可及的に低減される。したがって、最も精度の要求される歯車に対して可及的に精度を向上させる歯車伝達機構を実現できる。
0025
【Effect of the invention】
As described above , according to the present invention, in a gear transmission mechanism in which at least three or more gears are continuous, the gear requiring the highest accuracy is an intermediate gear, and the two front and rear gears are a drive gear and a driven gear, respectively. When this is done, the meshing ratio of the driven gear and the intermediate gear is the highest, and the driven gear is driven by a configuration in which the state of the meshing portion of the drive gear and the intermediate gear and the meshing portion of the driven gear and the intermediate gear are always matched. In the state where the disturbance due to the load fluctuation of the gear is most likely to propagate to the intermediate gear, the meshing ratio between the drive gear and the intermediate gear is also the highest at the same time. Therefore, the intermediate gear is most strongly restrained by the drive gear, and constant velocity rotation is easily transmitted, the intermediate gear is less affected by the load fluctuation of the driven gear, and the angular velocity fluctuation of the intermediate gear is reduced as much as possible. Therefore, it is possible to realize a gear transmission mechanism that improves the accuracy as much as possible for the gear that requires the highest accuracy.
【図面の簡単な説明】
【図１】
（ａ）は本発明の第一の実施例における歯車伝達機構の斜視図、（ｂ）は本発明の第一の実施例における歯車伝達機構の側面図
【図２】
（ａ），（ｂ），（ｃ）は、本発明の第一の実施例における歯車伝達機構の説明のための参考図
【図３】
本発明の第二の実施例における歯車伝達機構の側面図
【図４】
本発明の第三の実施例における歯車伝達機構の斜視図
【図５】
本発明の第四の実施例における画像形成装置の断面図
【図６】
本発明の第四の実施例における画像形成装置の部分拡大図
[Simple explanation of drawings]
FIG. 1
(A) is a perspective view of the gear transmission mechanism according to the first embodiment of the present invention, and (b) is a side view of the gear transmission mechanism according to the first embodiment of the present invention. FIG.
(A), (b), and (c) are reference views for explaining the gear transmission mechanism in the first embodiment of the present invention (FIG. 3).
FIG. 4 is a side view of a gear transmission mechanism according to a second embodiment of the present invention.
FIG. 5 is a perspective view of a gear transmission mechanism according to a third embodiment of the present invention.
FIG. 6 is a cross-sectional view of an image forming apparatus according to a fourth embodiment of the present invention.
Partially enlarged view of the image forming apparatus in the fourth embodiment of the present invention