Device for and method of coupling shafts, image formation apparatus, process cartridge, and belt unit

A shaft coupling device which couples a first shaft and a second shaft together, comprising:

• a grip unit to be attached to the first shaft and including a grip portion configured to grip the second shaft, the grip portion having an end with a plurality of grip portions forming notches of a length being parallel with an axial direction of the first shaft;
• and
• a grip force acting unit to be attached to the second shaft and configured to cause a grip force for gripping the second shaft to act on the grip portion by moving each of said grip portions in a radial direction towards the second shaft,
• wherein the grip portion and the first shaft are one piece.

A shaft coupling device which couples a first shaft and a second shaft together, comprising:

• a grip unit to be attached to the first shaft and including a grip portion configured to grip the second shaft, the grip portion having an end with a plurality of grip portions forming notches of a length being parallel with an axial direction of the first shaft;
• and
• a grip force acting unit to be attached to the second shaft and configured to cause a grip force for gripping the second shaft to act on the grip portion by moving each of said grip portions in a radial direction towards the second shaft,
• wherein the first shaft and the second shaft have end portions, the end portions being coupled to each other and respectively inserted into a shaft center holding portion configured to hold the first shaft and the second shaft coaxially to each other, and wherein the shaft center holding portion is positioned at a distance away from a tip of the end of the grip portion, the distance being greater than the length of the notches.

A shaft coupling device which couples a first shaft and a second shaft together, comprising:

• a grip unit to be attached to the first shaft and including a grip portion configured to grip the second shaft, the grip portion having an end with a plurality of grip portions forming notches of a length being parallel with an axial direction of the first shaft;
• and
• a grip force acting unit to be attached to the second shaft and configured to cause a grip force for gripping the second shaft to act on the grip portion by moving each of said grip portions in a radial direction towards the second shaft,
• wherein the grip force acting unit causes the grip force to act on the grip portion by abutting on the grip portion to move the grip portion in the radial direction when the grip force acting unit is moved toward the grip unit, and
• the grip force acting unit and the grip unit include screw portions, and the grip force acting unit moves toward the grip unit when the screw portions are screwed onto each other.

A shaft coupling device which couples a first shaft and a second shaft together, comprising:

• a grip unit to be attached to the first shaft and including a grip portion configured to grip the second shaft, the grip portion having an end with a plurality of grip portions forming notches of a length being parallel with an axial direction of the first shaft;
• and
• a grip force acting unit to be attached to the second shaft and configured to cause a grip force for gripping the second shaft to act on the grip portion by moving each of said grip portions in a radial direction towards the second shaft,
• wherein the grip force acting unit causes the grip force to act on the grip portion by abutting on the grip portion to move the grip portion in the radial direction when the grip force acting unit is moved toward the grip unit, and
• a contacting portion of the grip unit at which the grip unit contacts the grip force acting unit is tapered, and the grip force acting unit abuts on the contacting portion to move the grip portion in the radial direction when the grip force acting unit is moved toward the grip unit.

A shaft coupling device which couples a first shaft and a second shaft together, comprising:

• a grip unit to be attached to the first shaft and including a grip portion configured to grip the second shaft, the grip portion having an end with notches of a length being parallel with an axial direction of the first shaft;
• and
• a grip force acting unit to be attached to the second shaft and configured to cause a grip force for gripping the second shaft to act on the grip portion by moving the grip portion in a radial direction of the second shaft;
• wherein the grip force acting unit is a clamp member configured to fasten the grip portion from around substantially an entire outer periphery of the grip portion.

A shaft coupling device that couples a first shaft and a second shaft, comprising:

• a grip unit including a parallel surface parallel with a central axis of the first shaft and configured to grip the second shaft by abutting the parallel surface on the second shaft;
• and
• a grip force acting unit configured to cause a grip force for gripping the second shaft to act on the parallel surface,
• wherein the grip force acting unit moves along an outer peripheral surface of the grip unit in parallel with a central axis of the second shaft to change a pressure acting on the grip unit,
• the parallel surface of the grip unit is caused to abut on an outer peripheral surface of the second shaft by the pressure to grip the second shaft, and
• wherein the grip force acting unit and the grip unit can be screwably engaged with each other such that a tightening of the screwable engagement causes the plurality of the grip portions to move radially towards the second shaft.

A shaft coupling device that couples a first shaft and a second shaft, comprising:

• a grip unit including a parallel surface parallel with a central axis of the first shaft and configured to grip the second shaft by abutting the parallel surface on the second shaft;
• and
• a grip force acting unit configured to cause a grip force for gripping the second shaft to act on the parallel surface,
• wherein the grip force acting unit moves along an outer peripheral surface of the grip unit in parallel with a central axis of the second shaft to change a pressure acting on the grip unit,
• the parallel surface of the grip unit is caused to abut on an outer peripheral surface of the second shaft by the pressure to grip the second shaft,
• one of the first shaft and the second shaft is a rotating member supporting shaft configured to support a rotating member and another one of the first shaft and the second shaft is an output shaft of a motor configured to rotate the rotating member supporting shaft, and
• the grip force acting unit rotates around and moves in parallel with the central axis of the output shaft as the grip force acting unit is screwed onto the grip unit.

An image formation apparatus comprising:

• a rotating member supporting shaft configured to support a rotating member;
• an output shaft of a motor configured to rotate the rotating member supporting shaft;
• and
• a shaft coupling device
• configured to couple the rotating member supporting shaft and the output shaft, and includes
• a grip unit having a grip portion to be attached to one of the rotating member supporting shaft and the output shaft to grip a remaining shaft of the rotating member supporting shaft and the output shaft wherein the grip portion has an end with a plurality of split grip portions forming notches of a length being parallel with an axial direction of the output shaft, and
• a grip force acting unit to be attached to the remaining shaft to cause a grip force for gripping the remaining shaft to act on the grip portion by moving the grip portion in a radial direction of the remaining shaft wherein said grip force acting unit comprises a clamp member configured to fasten the grip portion from around substantially an entire outer periphery of the grip portion.

An image formation apparatus comprising:

• a rotating member supporting shaft configured to support a rotating member;
• an output shaft of a motor configured to rotate the rotating member supporting shaft;
• and
• a shaft coupling device
• configured to couple the rotating member supporting shaft and the output shaft, and
• includes
• a grip unit including a parallel surface parallel with a central axis of the output shaft and configured to grip the rotating member supporting shaft by abutting the parallel surface on the rotating member supporting shaft, and
• a grip force acting unit configured to cause a grip force gripping the rotating member supporting shaft to act on the parallel surface,
• wherein the grip force acting unit moves along an outer peripheral surface of the grip unit in parallel with a central axis of the output shaft to change a pressure acting on the grip unit, and
• the parallel surface of the grip unit is caused to abut on an outer peripheral surface of the rotating member supporting shaft by the pressure to grip the rotating member supporting shaft.