foil contacts of the cassette when the number of the cleaning times reaches a predetermined number a cleaning time setting means works to cut off the power for the motor making the cleaning assembly rested on a lateral portion of the housing so as to prevent the dirts from remaining on the contacts of the cassette and ensure the cleaning effect application_number US 44454495 A description please refer to fig1 to 7 the automatic cleaning device 50 of the present invention includes a housing 51 two cleaning assemblies 52 65 a cleaning arm 53 a crank 54 and a motor 55 the housing 51 consists of an upper case 57 and a lower case 58 the upper case 57 includes two at least one cassette insertion sockets 56 69 formed on the surface of the upper case 57 whereby different kinds of tv game cassettes 91 92 93 94 95 as shown in fig1 18 19 20 21 can be inserted and located therein to form the states as shown in fig1 13 14 15 16 please refer to fig3 10 and 11 the lower case 58 has two at least one linear guide rails 61 107 formed inside the lower case 58 corresponding to the insertion sockets 56 69 respectively the cleaning assemblies 52 65 are slidably disposed on the guide rails 61 107 and extended into the insertion sockets 56 69 respectively the cleaning assemblies 52 65 can reciprocally move along the guide.