means 11 4 will deform thus enabling the rigid support to oscillate and the cleaner 1 to advance across the surface to be cleaned the degree of oscillation of the rigid support 11 may be controlled by the degree of flexibility elasticity length thickness and shape of attached resilient biasing means 11 4 fig1 provides an example of a rigid support 11 mounted to the housing 5 of a cleaning device 1 and oriented at an inclination to the surface 2 to be cleaned by resilient biasing means 11 4 the support 11 includes an upper end 11 8 shaped for pivotal engagement with a pivot member 11 6 integrally formed with an adjacent support member 11 as stated in order to achieve forward movement in response to vibration the free end of each support must be capable of movement of up to a few millimeters the rigid i e supports which do not bend and straighten along their length spring loaded supports 11 like those illustrated in fig1 through 11 achieve this by being oriented at an inclination relative to the surface 2 to be cleaned and by attachment to the cleaning device i in a manner which will enable the supports 11 to oscillate about an axis generally lateral to a downward force 14 as disclosed below alternative support configurations can achieve the required movement of their free ends by other means fig1 a 12b 13 a 13 b.