Surface treating machine with controlled delivery

Abstract

A surface treatment machine, comprising a frame configured to translate with respect to a surface to treat, a surface treatment element connected to said frame and configured to treat with liquid a surface, a reservoir connected to the frame to provide liquid to the surface treatment element through a delivery mouth; an adjustment element arranged to feed adjustably the liquid supplied from the reservoir to the delivery mouth. A sensor is configured to measure an operating parameter P of the machine, such as the level of residual liquid in the reservoir, or the flow-rate of the liquid from said reservoir towards the delivery mouth, or the speed of the machine. A control unit receives by the sensor a signal proportional to operating parameter P and for adjusting the adjustment element responsive to operating parameter P, in order to deliver the liquid according to a predetermined function f(P) of optimization of the flow-rate. It is possible then to maximize the range of the machine, and to optimize the working time of the operator.

1 . A surface treatment machine, comprising:
 a frame configured to translate with respect to a surface to treat,   a surface treatment element connected to said frame and configured to treat with liquid a surface with respect to which said frame advances,   a reservoir connected to said frame and arranged to provide liquid to said surface treatment element through a delivery mouth;   an adjustment element arranged to adjustably pulse-feed the liquid provided from said reservoir to said delivery mouth;   characterized in that it comprises furthermore:   a sensor configured to measure an operating parameter P of said machine, selected from the group consisting of: level of liquid P 1  residual in the reservoir, actual flow-rate P 2  of the liquid from said reservoir towards said delivery mouth simultaneously to the pulses, speed P 3  of said machine relatively to said surface, or a combination thereof;   a control unit arranged to receive from said sensor a signal proportional to said operating parameter P and configured to adjust said adjustment element responsive to said operating parameter P, in order to pulse-feed said liquid with a duty cycle t%, expressed as a ratio between the duration of a pulse of the pulse-feed step and the time between two consecutive pulses, determined according to a predetermined function t%=f(P) of optimization of the flow-rate, wherein said function f(P) is selected from the group consisting of:
   t%=f(P 1 )=K 1 *P 1   −1/2   (1)
 
   t%=f(P 2 )=K 2 *P 2   −1   (2)
 
   t%=f(P 3 )=K 3 *P 3   (3).
 
   
     
     
         2 . Surface treatment machine according to  claim 1 , wherein said operating parameter P is a measurement of the level of liquid present in said reservoir, and said sensor is a sensor of a value P 1  proportional to said level of liquid present in said reservoir and said function f(P) is a function f(P 1 ) of optimization of the flow-rate calculated on said value P 1 , said sensor selected from the group consisting of:
 a pressure sensor communicating with said reservoir and arranged to provide a signal of pressure owing to a liquid head starting from the liquid surface of said reservoir;   a force sensor which can be arranged to hold the weight of support elements of said reservoir;   a level sensor which is located in said reservoir, and configured to measure the distance of the liquid surface of the liquid from a bottom wall or from a top wall of said reservoir.   
     
     
         3 . Surface treatment machine according to  claim 2 , wherein said adjustment element is selected from the group consisting of:
 a piloted valve, wherein said control unit is configured to adjust an opening section in a pulse-feed way of said valve , with a predetermined duty cycle t%, by adjusting the time for opening said valve in an increasing way responsive to decrease of the level of liquid P 1  according to said function f(P 1 );   an adjustable pump, wherein said control unit is configured to cause the pump to pulse-feed the liquid, with a predetermined duty cycle t%, by adjusting a pulse-feed rate of said pump in an increasing way responsive to decrease of the level of liquid P 1  according to said function f(P 1 ).   
     
     
         4 . Surface treatment machine according to  claim 1 , wherein said operating parameter P is a measurement of the flow-rate P 2  of liquid that comes to said delivery mouth, and said sensor is a flow-rate sensor, which are located between said reservoir to said delivery mouth configured to provide a signal P 2  proportional to said flow-rate, said function f(P) being a function f(P 2 ) of optimization of the flow-rate calculated on said value P 2 , and said adjustment element is selected from the group consisting of:
 a piloted valve, configured to pulse-feed the liquid, with a predetermined duty cycle t%, wherein said control unit is configured to adjust said duty cycle t% according to said function f(P 2 );   an adjustable pump, configured to pulse-feed the liquid, with a predetermined duty cycle t%, wherein said control unit is configured to adjust a pulse-feed rate of said pump according to said function f(P 2 ).   
     
     
         5 . Surface treatment machine according to  claim 1 , wherein said operating parameter P is a measurement of the translation speed of said frame with respect to said surface to treat, wherein said sensor is a speed sensor configured to provide a value P 3  proportional to said speed and said function f(P) is a function f(P 3 ) of optimization of the flow-rate calculated on said value P 3 , said adjustment element selected from the group consisting of:
 a piloted valve, wherein said control unit is configured to pulse-feed the liquid, with a predetermined duty cycle t%, by adjusting the opening said valve with duty cycle t% increasing responsive to an increase of said speed according to said function f(P 3 );   an adjustable pump, wherein said control unit is configured to pulse-feed the liquid, with a predetermined duty cycle t%, wherein said control unit is configured to adjust a pulse-feed rate in an increasing way responsive to an increase of said speed according to said function f(P 3 ).   
     
     
         6 . Surface treatment machine according to  claim 5 , wherein said frame is configured to translate with respect to said surface to treat by means of wheels, and said sensor configured to provide a value P 3  proportional to a speed of said machine is an encoder arranged to measure the speed of one of said wheels. 
     
     
         7 . Surface treatment machine according to  claim 5 , wherein said frame is configured to translate with respect to said surface to treat operated by a motor, and said sensor configured to provide a value P 3  proportional to a speed of said machine is a sensor configured to measure the pulse-width modulation (PWM) of said motor. 
     
     
         8 . Surface treatment machine according to  claim 2 , wherein said operating parameter P is a combination of a measurement P 3  of the translation speed of said frame and of a measurement Pi of the level of liquid present in said reservoir or of a measurement P 2  of the flow-rate of liquid that comes to said delivery mouth, said function f(P) configured to maximize the range of the machine of said machine starting from settings of said machine given by the nature of said surface and/or by environmental conditions, said range of the machine being calculated as residual time or residual surface that can be treated by said machine before replenishment of liquid in said reservoir. 
     
     
         9 . Surface treatment machine according to  claim 1 , wherein said control unit is associated with a display unit of said operating parameter and of a value of range of the machine calculated on the basis of instant values of said function f(P), said range of the machine being calculated as residual time or residual surface that can be treated by said machine before replenishment of liquid in said reservoir. 
     
     
         10 . A method of treatment of surfaces, comprising the steps of:
 translating a surface treatment machine with respect to a surface to treat, said machine having a surface treatment element connected to a frame;   feeding, at said surface treatment element, a treatment liquid, so that said surface treatment element treats with said liquid said surface during said translating;   said treatment liquid being drawn from a reservoir connected to said frame, in order to provide said liquid to said surface treatment element through a delivery mouth;   adjusting said delivery of liquid provided from said reservoir to said delivery mouth;   characterized in that it comprises furthermore:   measuring by a sensor an operating parameter P of said machine, selected from the group consisting of: level P 1  of residual liquid in the reservoir, actual flow-rate P 2  of the liquid from said reservoir towards said delivery mouth, speed P 3  of said machine relatively to said surface, or a combination thereof;   wherein said adjusting is carried out on the basis of a signal proportional to said operating parameter P and of said adjustment element responsive to said operating parameter P, in order to pulse-feed said liquid with a duty cycle t%, expressed as a ratio between the duration of a pulse of the pulse-feed step and the time between two consecutive pulses, determined according to a predetermined function t%=f(P) of optimization of the flow-rate, wherein said function f(P) is selected from the group consisting of:
   t%=f(P 1 )=K 1 *P 1   −1/2   (1)
 
   t%=f(P 2 )=K 2 *P 2   −1   (2)
 
   t%=f(P 3 )=K 3 *P 3   (3).
 
   
     
     
         11 . Surface treatment machine according to  claim 2 , wherein the force sensor is a load cell. 
     
     
         12 . Surface treatment machine according to  claim 2 , wherein the level sensor is selected from the group consisting of: an optical sensor or ultrasonic pulse sensor or floating sensor. 
     
     
         13 . Surface treatment machine according to  claim 4 , wherein the flow-rate sensor is a flow meter or liter-counter.