Floor cleaning apparatus

Abstract

Floor cleaning apparatus ( 1 ) comprising: a) a front portion ( 16 ) and a rear portion ( 17 ); the rear portion ( 17 ) comprising two lateral rear wheels ( 3 ); b) a chassis ( 2 ) and c) a cleaning unit ( 4 ) attached to the chassis ( 2 ), wherein the cleaning unit ( 4 ) comprises at least one rotatable brush ( 20 ) which is arranged in the front portion ( 16 ) of the cleaning apparatus ( 1 ) so as to be contactable with the floor ( 12 ) to be cleaned and a suction device ( 25 ) including a front suction unit ( 8 ) arranged in front of the at least one brush ( 20 ) and a rear suction unit ( 7 ) arranged rearward of the at least one brush ( 20 ), wherein the front suction unit ( 8 ) comprises a front suction channel ( 29 ) and a closing member ( 26 ) for closing the front suction channel ( 29 ).

1 . A floor cleaning apparatus comprising:
 a front portion;   a rear portion comprising two lateral rear wheels;   a chassis; and   a cleaning unit attached to the chassis; wherein the cleaning unit comprises:   at least one rotatable brush which is arranged in the front portion of the cleaning apparatus so as to be contactable with a floor to be cleaned; and   a suction device including a front suction unit arranged in front of the at least one brush and a rear suction unit arranged rearward of the at least one brush; and   wherein the front suction unit comprises a front suction channel and a closing member for closing the front suction channel.   
     
     
         2 . The floor cleaning apparatus according to  claim 1 , wherein the closing member closes the front suction channel when the floor cleaning apparatus is moved in a forward travel direction. 
     
     
         3 . The floor cleaning apparatus according to  claim 1 , wherein the closing member opens the front suction channel when the floor cleaning apparatus is moved in a backward travel direction. 
     
     
         4 . The floor cleaning apparatus according to  claim 1 , wherein the rear suction unit comprises a rear suction channel which remains open when the floor cleaning apparatus is moved in a forward and when the floor cleaning apparatus is moved in a backward travel direction. 
     
     
         5 . The floor cleaning apparatus according to  claim 1 , wherein the front suction channel comprises a suction opening which is open towards the floor to be cleaned over an entire length of the front suction unit, and wherein the closing member closes the suction opening of the front suction channel when the floor cleaning apparatus is moved in a forward travel direction and opens the suction opening when the floor cleaning apparatus is moved in a backward travel direction. 
     
     
         6 . The floor cleaning apparatus according to  claim 1 , wherein the front suction channel comprises a suction opening which is open towards the floor to be cleaned, and wherein the closing member comprises a lip with a front section, which frontally limits the suction opening along its entire length, and a rear section which rearwardly limits the suction opening along its entire length. 
     
     
         7 . The floor cleaning apparatus according to  claim 6 , wherein the closing member is actuated by frictional forces acting on the front section of the lip due to a sliding movement of the same on the floor to be cleaned when the floor cleaning apparatus is moved with the front portion of the floor cleaning apparatus ahead or with the rear portion of the floor cleaning apparatus ahead. 
     
     
         8 . The floor cleaning apparatus according to  claim 6 , wherein the lip is made of a resilient material. 
     
     
         9 . The floor cleaning apparatus according to  claim 6 , wherein the front section of the lip has a vertical height HF and the rear section of the lip has a vertical height HR, and wherein HF is larger than HR so that the front section is bendable across the suction opening. 
     
     
         10 . The floor cleaning apparatus according to  claim 6 , wherein the front section of the lip is bendable as far as a portion of the front section extends below the rear section. 
     
     
         11 . The floor cleaning apparatus according to  claim 1 , wherein the rear suction unit comprises a rear suction channel, and wherein both of the front suction channel and the rear suction channel are connected to a manifold so as to be in fluid connection with a single vacuum turbine. 
     
     
         12 . The floor cleaning apparatus according to  claim 1 , wherein the front suction unit and the rear suction unit extend transverse to forward and backward travel directions of the cleaning apparatus. 
     
     
         13 . The floor cleaning apparatus according to  claim 1 , wherein when measured orthogonal to a vertical middle plane of the cleaning apparatus the front suction unit and the rear suction unit each have a length which is equal to or larger than a dimension of the at least one brush measured orthogonal to the vertical middle plane. 
     
     
         14 . The floor cleaning apparatus according to  claim 1 , wherein the cleaning apparatus further comprises a brush housing, and wherein the rear suction unit is attached to the brush housing by a resilient connecting device allowing the rear suction unit to move laterally with respect to the chassis against an elastic resistance provided by the resilient connecting device. 
     
     
         15 . The floor cleaning apparatus according to  claim 14 , wherein the resilient connecting device comprises an elastic connector, which forms a pivot joint affixed to the brush housing by means of a fastener. 
     
     
         16 . The floor cleaning apparatus according to  claim 15 , wherein the pivot joint has an axis of rotation extending essentially vertically. 
     
     
         17 . The floor cleaning apparatus according to  claim 1 , wherein the rear suction unit comprises a curved suction bar. 
     
     
         18 . The floor cleaning apparatus according to  claim 14 , wherein the resilient connecting device comprises an elongated bracket having a first end affixed to the rear suction unit and a second end attached to the brush housing by means of an elastic connector. 
     
     
         19 . The floor cleaning apparatus according to  claim 18 , wherein the elongated bracket is biased in a position of rest by means of the elastic connector, and wherein when in the position of rest the elongated bracket extends along a forward or backward travel direction of the floor cleaning apparatus. 
     
     
         20 . The floor cleaning apparatus according to  claim 1 , wherein the at least one brush is rotatable about a rotational axis extending essentially vertically. 
     
     
         21 . The floor cleaning apparatus according to  claim 1 , wherein the floor cleaning apparatus further comprises a handlebar, which allows the floor cleaning apparatus to be moved on the floor to be cleaned. 
     
     
         22 . The floor cleaning apparatus according to  claim 1 , wherein the rear suction unit is arranged in front of the rear wheels. 
     
     
         23 . The floor cleaning apparatus according to  claim 1 , further comprising a first tank, which is attachable to the chassis and which is configured as a receptacle with its smallest dimension X extending vertically. 
     
     
         24 . The floor cleaning apparatus according to  claim 23 , further comprising a second tank, which is arranged in the rear portion of the floor cleaning apparatus and which is configured as a receptacle having a smallest dimension Z in the forward or rearward travel direction of the floor cleaning apparatus. 
     
     
         25 . The floor cleaning apparatus according to  claim 24 , further comprising an elongated member, which extends from a rear end of the chassis, and wherein the second tank is attachable to the elongated member. 
     
     
         26 . The floor cleaning apparatus according to  claim 25 , wherein one end of the elongated member is rotatably affixed to the chassis by means of a hinge. 
     
     
         27 . A method of cleaning a floor using the floor cleaning apparatus according to  claim 1 , the method comprising the steps of:
 moving the floor cleaning apparatus in a forward travel direction to close the front suction channel so as to apply an increased vacuum in the rear suction channel which remains open when the floor cleaning apparatus is moving in the forward travel direction; and/or   moving the floor cleaning apparatus in a backward travel direction to open the front suction channel so as to obtain a high combined suction volume flow through the open front suction channel and the open rear suction channel.