Abstract: A balance shaft structure includes a balance shaft including a balance weight, a driven gear to rotate the balance shaft by being engaged with a drive gear, a scissors mechanism, whose position in an axial direction is regulated, including a scissors gear to reduce backlash between the drive gear and the driven gear and an axially urging member to urge the scissors gear toward the driven gear in the axial direction, a first regulating portion to regulate an axially inner position of the scissors mechanism, and a second regulating portion fixed to the balance shaft on a side close to the shaft end part of the balance shaft beyond the first regulating portion and configured to regulate an axially outer position of the scissors mechanism.

Abstract: A balance shaft structure includes a balance shaft including a balance weight, a driven gear to rotate the balance shaft by being engaged with a drive gear, a scissors mechanism, whose position in an axial direction is regulated, including a scissors gear to reduce backlash between the drive gear and the driven gear and an axially urging member to urge the scissors gear toward the driven gear in the axial direction, a first regulating portion to regulate an axially inner position of the scissors mechanism, and a second regulating portion fixed to the balance shaft on a side close to the shaft end part of the balance shaft beyond the first regulating portion and configured to regulate an axially outer position of the scissors mechanism.

Abstract: A molding sand preparation apparatus of the mixing-bowl type is suitable for preparing face sand or back sand without structural modification. The apparatus includes sand hoppers and resin and catalyst tanks as well as pumps, controls and the like for measuring proper amounts of sand, resin and catalyst and placing them into a mixing bowl equipped with rotatable agitating blades. The bowl includes flexible mixing blades, the position of which can be adjusted for changing the mixing efficiency of the apparatus.