1. A developer supplier for supplying a developer to an image forming mechanism, comprising:
a developer container configured to contain the developer;
a conveyer configured to convey the developer from the developer container to the image forming mechanism;
a sensor disposed at a predefined position on an interior wall of the developer container and configured to detect the developer at the predefined position in the developer container;
an agitator configured to rotate and to agitate the developer, and including a paddle formed in a plate-like shape and including an opening through which a part of the developer slips and avoids being paddled by the paddle; and
a driver configured to drive the conveyer and the agitator at a variable speed.
2. An image forming apparatus, comprising:
an image forming mechanism configured to contain a developer and to form an image with the developer; and
a developer supplier configured to supply the developer to the image forming mechanism, and including
a developer container configured to contain the developer,
a conveyer configured to convey the developer from the developer container to the image forming mechanism,
a sensor disposed at a predefined position on an interior wall of the developer container and configured to detect the developer at the predefined position in the developer container,
an agitator configured to rotate to agitate the developer, and including a paddle formed with a plate-like shape and including an opening through which a part of the developer slips and avoids being paddled by the paddle, and
a driver configured to drive the conveyer and the agitator at a variable speed.
3. An image forming apparatus, comprising:
an image forming mechanism configured to contain a developer and to form an image with the developer; and
a developer supplier configured to supply the developer to the image forming mechanism, and including
a developer container configured to contain the developer,
a conveyer configured to convey the developer from the developer container to the image forming mechanism,
a sensor disposed at a predefined position on an interior wall of the developer container and configured to detect the developer at the predefined position in the developer container,
an agitator configured to rotate and to agitate the developer,
a driver configured to drive the conveyer and the agitator at a variable speed, and
an agitation adjuster configured to suppress an increase in flowability of the developer increased by agitation thereof by the agitator.
4. The image forming apparatus according to claim 3,
wherein the agitation adjuster includes a driving control mechanism configured to alternately drive and stop the driver in accordance with rotational speed of the agitator.
5. The image forming apparatus according to claim 3,
wherein the agitator includes a paddle formed in a plate-like shape, said paddle including an opening through which a part of the developer slips and avoids being paddled by the paddle.
6. The image forming apparatus according to claim 4,
wherein the driving control mechanism alternately drives and stops the driver at a specific duty ratio of not greater than about 75 percent, the specific duty ratio being of a time period of the drive to a total time period of the drive and the stop.
7. The image forming apparatus according to claim 2,
wherein the agitator includes a flexible material.
8. The image forming apparatus according to claim 7,
wherein the sensor includes a detecting surface and the agitator scrapes the detecting surface.
9. The image forming apparatus according to claim 8,
wherein the developer supplier further includes a first rotating shaft for supporting and rotating the agitator, and
wherein the agitator has a length greater than a distance from the first rotating shaft to the detecting surface of the sensor and a width greater than the detecting surface of the sensor.
10. The image forming apparatus according to claim 9,
wherein the agitator scrapes the detecting surface of the sensor upward.
11. The image forming apparatus according to claim 9,
wherein the first rotating shaft extends in a direction perpendicular to a direction in which the developer moves in the developer container.
12. The image forming apparatus according to claim 2,
wherein an accelerated agglomeration of the developer is not greater than about 15 percent.
13. The image forming apparatus according to claim 9,
wherein the developer supplier further includes a second rotating shaft for supporting and rotating the conveyer, and
wherein the conveyer is formed in a coil-like shape and rotates to convey the developer in a direction in which the second rotating shaft extends.
14. The image forming apparatus according to claim 2,
wherein the conveyer is disposed in a lower portion of the developer container and the developer is supplied from an upper portion of the developer container.
15. The image forming apparatus according to claim 13,
wherein the developer supplier further includes a first gear disposed on the first rotating shaft and a second gear disposed on the second rotating shaft and the first and second gears are engaged with each other to transmit a driving force, and
wherein the second rotating shaft is nonconcurrently disposed with respect to the first rotating shaft.
16. The image forming apparatus according to claim 15,
wherein the first and second gears have a common number of gear teeth.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An automatic tappet clearance adjusting apparatus for adjusting a clearance between a valve and an adjustment screw in an engine, in which the valve that is closed by a spring is opened by being pressed by an adjustment screw on a distal end of a rocker arm, comprising:
an adjustment unit for advancing and retracting said adjustment screw from a distal end of said rocker arm to adjust a projection of the adjustment screw;
a torque detector for detecting a torque to rotate said adjustment screw; and
a control mechanism for controlling said adjustment unit based on a torque value measured by said torque detector,
wherein said control mechanism successively detects said torque value applied to retract said adjustment screw to close said valve from a state in which said valve is open, and detects, as a reference point, a point of intersection of a first straight line, which corresponds to a time zone immediately before an inflection point at which a differential value of said torque value changes, with a second straight line which corresponds to a time zone immediately after the inflection point, and then retracts said adjustment screw by a set quantity based on said clearance from said reference point.
2. An automatic tappet clearance adjusting apparatus according to claim 1, wherein said control mechanism detects, as the reference point, a location in which a valve head of said valve first contacts a valve seat of said engine to begin reducing said torque value.
3. An automatic tappet clearance adjusting apparatus according to claim 1, wherein said control mechanism detects, as the reference point, a location in which after a valve head of said valve contacts a valve seat of said engine, said adjustment screw is spaced from an end of said valve to hold said torque value at a constant value.
4. An automatic tappet clearance adjusting apparatus according to claim 1, wherein said torque detector comprises:
a drive unit connected to a rotary drive source;
a driven unit coupled to a tool for rotating said adjustment screw, said driven unit being coaxial with said drive unit;
a drive force transmitting engagement unit for transmitting rotation in both directions of said drive unit to said driven unit; and
a load cell disposed in said drive force transmitting engagement unit, for detecting a force in one circumferential direction,
wherein said load cell is preloaded in said one circumferential direction by a resilient body.
5. An automatic tappet clearance adjusting apparatus according to claim 1, further comprising:
a rocker arm measuring unit for detecting a displacement of said rocker arm; and
a moving mechanism programmed for setting a position and direction of said adjustment unit,
wherein said moving mechanism sets the position and direction of said adjustment unit based on the displacement of the rocker arm measured by said rocker arm measuring unit, and brings said adjustment unit into engagement with said adjustment screw.
6. An automatic tappet clearance adjusting apparatus according to claim 1, wherein said adjustment unit is moved by a programmable multiaxis robot.
7. An automatic tappet clearance adjusting apparatus according to claim 1, wherein the tappet clearance adjusting apparatus is installed in a station on a production line.
8. An automatic tappet clearance adjusting method, for adjusting a clearance between a valve and an adjustment screw in an engine in which the valve that is closed by a spring is opened by being pressed by an adjustment screw on a distal end of a rocker arm comprising the step of employing:
an adjustment unit for advancing and retracting said adjustment screw from the distal end of said rocker arm in order to adjust the projection of the adjustment screw;
a torque detector for detecting a torque value to rotate said adjustment screw; and
a control mechanism for controlling said adjustment unit based on the torque value as measured by said torque detector,
wherein said control mechanism successively detects said torque value applied to retract said adjustment screw to close said valve from a state in which said valve is open, and detects, as a reference point, a point of intersection of a first straight line, which corresponds to a time zone immediately before an inflection point at which a differential value of said torque value changes, with a second straight line which corresponds to a time zone immediately after the inflection point, and then retracts said adjustment screw by a set quantity based on said clearance from said reference point.
9. An automatic tappet clearance adjusting method according to claim 8, wherein said control mechanism detects, as the reference point, a location at which a valve head of said valve first contacts a valve seat of said engine to begin reducing said torque value.
10. An automatic tappet clearance adjusting method according to claim 8, wherein said control mechanism detects, as the reference point, a location in which, after a valve head of said valve contacts a valve seat of said engine, said adjustment screw is spaced from an end of said valve in order to hold said torque value at a constant value.
11. An automatic tappet clearance adjusting method according to claim 8, wherein said torque detector comprises:
a drive unit connected to a rotary drive source;
a driven unit coupled to a tool) for rotating said adjustment screw, said driven unit being coaxial with said drive unit;
a drive force transmitting engagement unit for transmitting rotation in both directions of said drive unit to said driven unit; and
a load cell disposed in said drive force transmitting engagement unit, for detecting a force in one circumferential direction,
wherein said load cell is preloaded in said one circumferential direction by a resilient body.
12. An automatic tappet clearance adjusting method according to claim 8, further comprising the step of employing:
a rocker arm measuring unit for detecting a displacement of said rocker arm; and
a moving mechanism programmed for setting a position and direction of said adjustment unit,
wherein said moving mechanism sets the position and direction of said adjustment unit based on the displacement of the rocker arm measured by said rocker arm measuring unit, and brings said adjustment unit into engagement with said adjustment screw.
13. An automatic tappet clearance adjusting method according to claim 8, wherein said adjustment unit is moved by a programmable multiaxis robot.
14. An automatic tappet clearance adjusting method according to claim 8, wherein the tappet clearance adjusting method is carried out in a station on a production line.