Abstract: An ink jet recording apparatus includes a shaft for receiving rotational driving force; a clutch gear mounted on the shaft rotated by rotation of the shaft and movable in a longitudinal direction of the shaft; a transmission gear engageable with the clutch gear in accordance with movement and rotation of the clutch gear, wherein a predetermined mechanism is operated by rotation of the transmission gear by engagement with the clutch gear. The clutch gear includes a flange disposed at a position engageable with a portion of the transmission gear to prevent rotation of the transmission gear before the movement of the clutch gear for the engagement with the transmission gear; a starting tooth for engagement with a predetermined tooth of the transmission gear in accordance with the movement and the rotation; and a non-engagement portion faced to the transmission gear before the engagement of the starting teeth.

Abstract: A writing-pressure changing device for use in a recording device or the like in which when one end of a pen holder is caused to ascend by a device such as a plunger. In this device the pen holder is pivotally moved with respect to a pivot, so that a recording pen supported on the other end of the pen holder is caused to descend to be brought into contact with a recording surface to make a drawing. The writing pressure-changing device includes a first cylinder which has an inclined guide groove formed in a side wall thereof, and where the first cylinder is adapted to be mounted around the plunger; a second cylinder is slidably fitted in the first cylinder and has a switch lever formed on an outer peripheral surface of the second cylinder, the switch lever projects from the guide groove in the first cylinder, and the second cylinder is adapted to be mounted around the plunger. A spring is engaged with an inner side of an upper end of the second cylinder and carried by a lower end of the plunger.