Patent ID: 6102179
Filing Date: 2000-08-15
Classification: F16D

Abstract:
An inhaler for the inhalation of a powdered medicament comprising:a housing having an air inlet and, spaced therefrom, an air outlet, said air inlet and said air outlet defining a flow path for air through said housing during inhalation;an elongate carrier, at least a portion of which is disposed within said housing between said air inlet and said air outlet, said elongate carrier bearing the powdered medicament; andan advancement means for advancing said elongate carrier to position an area of the elongate carrier in a predetermined position in said flow path for dispensing a portion of the medicament from the carrier during inhalation, the advancement means comprising a device for the transmission of one-way torque comprising:an outer annular member having a plurality of radially inwardly projecting teeth, each tooth comprising a driving surface and a cam surface,a shaft concentrically mounted with respect to the outer annular member, the shaft comprising a plurality of drive elements each having a driving surface and a cam surface, two of said drive elements being interconnected to form a slider extending substantially diametrically across the shaft, said drive elements being mounted on the shaft in a manner allowing radial movement relative to the shaft,whereby:rotation of the shaft or outer annular member in its driving direction causes engagement of a driving surface of at least one drive element with a driving surface of at least one tooth thereby resulting in joint rotation of the shaft and outer annular member, androtation of the shaft or outer annular member in its non-driving direction causes engagement of the cam surface of at least one drive element with the cam surface of at least one tooth resulting in additional relative movement, substantially radially, between said drive element and said tooth thereby preventing rotational movement being transmitted between said shaft and said outer annular member,said engagement of the driving surfaces and the cam surfaces not requiring the presence of spring biasing means.