Abstract: A chip removal method removes residue such as chips that have remained in and adhered to an interior of a bag-shaped machined hole in a work piece. After air is jetted out and blown against a bottom portion of the machined hole by using an air blow nozzle to change a flow of air that is circulating inside a nozzle into a spiral flow that moves in a direction towards the bottom portion of the machined hole, this spiral flow then blows upwards like a tornado from a vicinity of the bottom portion of the machined hole in a direction towards an aperture portion of the machined hole so that the residue inside the machined hole is uplifted by the spiral flow and removed.

Abstract: A chip removal method removes residue such as chips that have remained in and adhered to an interior of a bag-shaped machined hole in a work piece. After air is jetted out and blown against a bottom portion of the machined hole by using an air blow nozzle to change a flow of air that is circulating inside a nozzle into a spiral flow that moves in a direction towards the bottom portion of the machined hole, this spiral flow then blows upwards like a tornado from a vicinity of the bottom portion of the machined hole in a direction towards an aperture portion of the machined hole so that the residue inside the machined hole is uplifted by the spiral flow and removed.

Abstract: A vacuum cleaner includes an optical dust sensor for detecting a quantity of dust which sensor is provided at a predetermined position of a suction path for sucking air by a suction force of the vacuum cleaner, whereby an output signal is supplied to a display device so that a display corresponding to the quantity of the sucked dust, which signal is output from the optical dust sensor and is varied in a stageless manner corresponding to the quantity of the dust.

Abstract: A vacuum cleaner with an indicator for indicating when the dust bag for the vacuum cleaner is full. The indicator includes a turbine provided in a suction pipe, so that the turbine causes an amount of electric power to be generated that corresponds to the amount of negative pressure within the suction pipe. As the dust bag begins to fill, the negative pressure in the suction pipe decreases, and the amount of electric power caused by the turbine also decreases. When the amount of electric power caused by the turbine falls below a predetermined value, the indicator display indicates that the bag is full. If the indicator is employed with a dust sensor, the indicator display can be used to show the amount of detected dust until the bag is full and the operation of the sensor is stopped to allow the display to indicate that the bag is full.

Abstract: A vacuum cleaner includes a dust sensor of the light emitting and light receiving type, which sensor detects the quantity of dust which is sucked during a cleaning operation. The vacuum cleaner also includes a sensitivity correction section which compensates for lowering of the dust detection sensitivity due to soiling of the dust sensor, a limit detection section which detects a condition in which the compensation of dust detection sensitivity by the sensitivity correction section reaches a limit value, and an information section which informs the vacuum cleaner user of the condition in which correction of the dust detection sensitivity by the sensitivity correction section has reached its limit value.

Abstract: A vacuum cleaner comprises a dust sensor having a light emitting device and a light receiving device which devices are provided at predetermined positions of a suction nozzle or a suction pipe in a condition that both devices are opposite to one another in a direction which crosses a dust suction direction by a predetermined angle. A spacer member is positioned at a predetermined accurately position the suction nozzle or the suction pipe by an engagement of with respect to a second projection member and a second concave section, and each device is positioned accurately relative to the spacer member by an engagement of a first concave section and a first projection member.

Abstract: A vacuum cleaner includes an optical dust sensor for detecting a quantity of dust which sensor is provided at a predetermined position of a suction path for sucking air by a suction force of the vacuum cleaner, whereby an output signal is supplied to a display device so that a display corresponding to the quantity of the sucked dust, which signal is output from the optical dust sensor and is varied in a stageless manner corresponding to the quantity of the dust.

Abstract: A method of silver plating stainless steel vacuum bottle surfaces includes the steps of thermally treating the surfaces to be coated at a temperature of at least 200.degree. C. and then using an electroless plating technique to silver plate the thermally treated surfaces. The thermal treatment can be as low as 200.degree. C. if it occurs in an atmosphere of at least 5% hydrogen gas. If the thermal treatment occurs in a vacuum, however, the temperature must be at least 700.degree. C.