Abstract: A vibrating device is incorporated in a packaging machine to vibrate packaging bags filled with articles. The vibrating device includes a tapping plate disposed below the bags, a servomotor having an output shaft, a selection unit selecting one of vibration patterns set according to sizes of the bags or types of the articles, an output unit delivering data of a rotation pattern of the output shaft, and a control unit controlling the output shaft according to the rotation pattern based on the delivered rotation data. When one vibration pattern is selected according to the size of the bag or the type of the articles, the control unit controls the output shaft according to the rotation pattern corresponding to the vibration pattern, so that the tapping plate connected via a link mechanism to the output shaft is vibrated up and down in the selected vibration pattern to vibrate the bag.

Abstract: A useful dry battery driven liquid pump for pumping liquid such as kerosene or the like into a tank for an oil heater or the like very conveniently includes a combination of a motor and a liquid pump disposed at the lower end part of a suction tube, a plurality of dry cells contained in a dry battery casing, a liquid surface level detector disposed at the lower end part of a delivery tube and a control circuit which controls operation of the liquid pump properly in response to an output from the liquid surface level detector. The liquid surface level detector includes a prism formed at the lower end of a cylindrical detector body, a light beam generating element and a light beam receiving element. The liquid pump is driven as long as the prism does not get wet with liquid and thus light is reflected from the inner optical surface of the prism toward the light beam receiving element.