Operating Apparatus

Abstract

The operating apparatus ( 500 ) suitable for operating first brakes of a front axle ( 501 ) and second brakes of a rear axle ( 502 ) of a vehicle comprises: first circuit means ( 503 ) and second circuit means ( 504 ) arranged to supply said first brakes and said second brakes with a pressurised fluid; first distributing means ( 505, 508 ) located between said first circuit means ( 503 ) and said second circuit means ( 504 ); supply means ( 23, 24 ) for said pressurised fluid; valve means ( 1 ) for sending said pressurised fluid to said first circuit means ( 503 ) and second circuit means ( 504 ), second distributing means ( 514, 515 ) being arranged between said first distributing means ( 505, 508 ) and said first brakes and second brakes arranged to deactivate said first distributing means ( 505, 508 ) in a malfunction condition of either said first circuit means ( 503 ) or second circuit means ( 504 ) and to connect said supply means ( 23, 24 ) with said first brakes or with said second brakes.

1 - 87 . (canceled) 
   
   
       88 . An operating apparatus ( 500 ) suitable for operating first brakes of a front axle ( 501 ) and second brakes of a rear axle ( 502 ) of a vehicle comprising: first circuit means ( 503 ) and second circuit means ( 504 ) arranged to supply said first brakes and said second brakes with pressurised fluid; first distributing means ( 505 ,  508 ) located between said first circuit means ( 503 ) and said second circuit means ( 504 ); supply means ( 23 ,  24 ) of said pressurised fluid; valve means ( 1 ) for sending said pressurised fluid to said first circuit means ( 503 ) and second circuit means ( 504 ), wherein said second distributing means ( 514 ,  515 ) are arranged between said first distributing means ( 505 ,  508 ) and said first brakes and second brakes arranged to deactivate said first distributing means ( 505 ,  508 ) in a malfunction condition of either said first circuit means ( 503 ) or second circuit means ( 504 ) and to connect said supply means ( 23 ,  24 ) with said first brakes or with said second brakes. 
   
   
       89 . The apparatus according to  claim 88 , wherein said second distributing means ( 514 ,  515 ) are arranged to keep said first distributing means ( 505 ,  508 ) active in a normal operating condition of said first circuit means ( 503 ) and second circuit means ( 504 ). 
   
   
       90 . The apparatus according to  claim 88 , wherein said second distributing means ( 514 ,  515 ) can be placed in at least two alternative operating positions ( 516 ,  517 ), in a first position ( 516 ) being arranged to connect said first distributing means ( 505 ,  508 ) and said first brakes and said first circuit means ( 503 ), second circuit means ( 504 ) and said second brakes, in a second position ( 517 ) being arranged to connect said first circuit means ( 503 ) and second circuit means ( 504 ) to said first brakes and said second brakes and to disconnect said first distributing means ( 505 ,  508 ) from said first brakes. 
   
   
       91 . The apparatus according to  claim 88 , wherein said valve means for sending comprise a hydraulic valve ( 1 ). 
   
   
       92 . The apparatus according to  claim 91 , wherein said hydraulic valve ( 1 ) comprises: body means ( 2 ) having first inlet means ( 21 ), second inlet means ( 22 ), first outlet means ( 25 ) and second outlet means ( 26 ); first distributing means and second distributing means ( 5 ) arranged to connect said first inlet means ( 21 ) to said first outlet means ( 25 ) and second inlet means ( 22 ) to said second outlet means ( 26 ) respectively, first thrust means ( 7 ) and second thrust means ( 8 ) arranged to operate said first distributing means ( 5 ) and second distributing means ( 6 ) respectively, between said first distributing means ( 5 ) and second distributing means ( 6 ) being provided a hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) so that said first distributing means ( 5 ) act on said second distributing means ( 6 ) and vice versa. 
   
   
       93 . A hydraulic valve, suitable for operating apparatus ( 500 ) of brakes of wheels on front axles and brakes of wheels on rear axles of a vehicle, comprising: body means ( 2 ) having first inlet means ( 21 ), second inlet means ( 22 ), first outlet means ( 25 ) and second outlet means ( 26 ); first distributing means and second distributing means ( 5 ) arranged to connect said first inlet means ( 21 ) to said first outlet means ( 25 ) and second inlet means ( 22 ) to said second outlet means ( 26 ) respectively, first thrust means ( 7 ) and second thrust means ( 8 ) arranged to operate said first distributing means ( 5 ) and second distributing means ( 6 ) respectively, wherein between said first distributing means ( 5 ) and second distributing means ( 6 ) a hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) is provided so that said first distributing means ( 5 ) act on said second distributing means ( 6 ) and vice versa. 
   
   
       94 . The valve according to  claim 93 , wherein between said first distributing means ( 5 ) and second distributing means ( 6 ) are interposed respective first opening/closing means and second opening/closing means ( 105 ;  106 ) for opening/closing said hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ). 
   
   
       95 . The valve according to  claim 94 , wherein said first opening/closing means and second opening/closing means ( 105 ;  106 ) for opening/closing said hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) are operated with said first thrust means ( 7 ) and second thrust means ( 8 ) respectively. 
   
   
       96 . The valve according to  claim 93 , wherein said first outlet means ( 25 ) and said second outlet means ( 26 ) are hydraulically separate. 
   
   
       97 . The valve according to  claim 93 , wherein said first outlet means ( 25 ) can be connected to a first hydraulic circuit for supplying first user means and said second outlet means ( 26 ) can be connected to a second hydraulic circuit for supplying second user means. 
   
   
       98 . The valve according to  claim 97 , wherein said first user means and second user means comprise a left-hand braking hydraulic circuit and a right-hand braking hydraulic circuit respectively of an operating machine. 
   
   
       99 . The valve according to  claim 93 , wherein said first inlet means ( 21 ) and second inlet means ( 22 ) can be connected to respective supply apparatus ( 23 ;  24 ) of pressurised fluid. 
   
   
       100 . The valve according to  claim 93 , wherein between said first outlet means ( 25 ) and second outlet means ( 26 ) are provided pressure compensation means ( 38 ;  39 ) of said pressurised fluid in said left-hand hydraulic circuit and right-hand hydraulic circuit. 
   
   
       101 . The valve according to  claim 93 , wherein said first distributing means comprise: a first sliding chamber ( 3 ) obtained in said body means ( 2 ); first slider means ( 205 ) fitted sliding into said first sliding chamber ( 3 ); first duct means ( 121 ,  125 ) arranged to connect said first sliding chamber ( 3 ) to said first inlet means ( 21 ) and said first outlet means ( 25 ), said first duct means comprising a first duct ( 121 ) arranged to connect said first sliding chamber ( 3 ) to said first inlet means ( 21 ); a third duct ( 125 ) arranged to connect said first sliding chamber ( 3 ) to said first outlet means ( 25 ), said first inlet means ( 21 ) and first outlet means ( 25 ) being controlled by said first slider means ( 205 ), said second distributing means ( 6 ) comprising: a second sliding chamber ( 4 ) obtained in said body means ( 2 ); second slider means ( 206 ) fitted sliding in said second sliding chamber ( 4 ); second duct means ( 122 ,  126 ) arranged to connect said second sliding chamber ( 4 ) to said second inlet means ( 22 ) and said second outlet means ( 26 ), said second duct means comprising: a second duct ( 122 ) arranged to connect said second sliding chamber ( 4 ) to said second inlet means ( 22 ); a fourth duct ( 126 ) arranged to connect said second sliding chamber ( 4 ) to said second outlet means ( 26 ), said second inlet means ( 22 ) and second outlet means ( 26 ) being controlled by said second slider means ( 206 ). 
   
   
       102 . The valve according to  claim 101 , wherein said first slider means ( 205 ) have a third perimeter groove ( 36 ) that can be aligned with said first duct ( 121 ) and/or third duct ( 125 ) and wherein said second slider means ( 206 ) have a fourth perimeter groove ( 37 ) that can be aligned with said second duct ( 122 ) and/or fourth duct ( 126 ). 
   
   
       103 . The valve according to  claim 101 , wherein said first sliding chamber ( 3 ) and second sliding chamber ( 4 ) are parallel and respectively comprise first sections ( 3 ′;  4 ′) having a first diameter and second sections ( 3 ″;  4 ″) having second diameters smaller than said first diameters, between said first diameters and said second diameters being defined ring-shaped connection shoulders ( 300 ). 
   
   
       104 . The valve according to  claim 103 , wherein between said first sections ( 3 ′;  4 ′) and said second sections ( 3 ″;  4 ″) discharge means ( 35 ,  135 ) are provided of said pressurised fluid. 
   
   
       105 . The valve according to  claim 101 , wherein said first sliding chamber ( 3 ) and second sliding chamber ( 4 ) have second concordant ending parts ( 203 ;  204 ) closed with cap means ( 9 ) and corresponding opposite open ending parts ( 103 ;  104 ) for the passage of concurrent ending parts ( 10 ;  11 ) of said first and second distributing means ( 5 ;  6 ), said second sections ( 3 ″;  4 ″) being turned towards said second concordant ending parts ( 203 ;  204 ) and said first sections ( 3 ′;  4 ′) being turned towards said first open ending parts ( 103 ;  104 ). 
   
   
       106 . The valve according to  claim 105 , wherein said first distributing means ( 5 ) and second distributing means ( 6 ) respectively comprise a further first and a further second thrust unit ( 7 ;  8 ) fitted sliding in said first sections ( 3 ′;  4 ′) with the interposition of sealing means ( 19 ) and a first and a second slider ( 105 ,  205 ;  106 ,  206 ) placed in axial extension of said first and second thrust unit ( 7 ,  8 ) towards said cap means ( 9 ). 
   
   
       107 . The valve according to  claim 106 , wherein said first and second thrust unit ( 7 ;  8 ) respectively comprise: first push rod elements ( 10 ) and second push rod elements ( 11 ) having corresponding ending parts ( 110 ;  111 ) which extend beyond said opposite first open ending parts ( 103 ;  104 ); elastic means ( 14 ,  15 ,  16 ;  14 ′, 15 ′,  16 ′) reactive to compression placed in between said first push rod element ( 10 ), second push rod element ( 11 ) and said ring-shaped shoulders ( 300 ). 
   
   
       108 . The valve according to  claim 107 , wherein said first push rod element ( 10 ) and second push rod element ( 11 ) comprise respective convex portions ( 110 ;  111 ) protruding towards the outside of said second open ending parts ( 103 ;  104 ) and opposite concave portions ( 210 ;  211 ) turned towards the inside of said first sections ( 3 ′;  4 ′), said convex portions ( 110 ;  111 ) being connectable to respective pedal means ( 12 ;  13 ) that can be operated from the outside. 
   
   
       109 . The valve according to  claim 108 , wherein said first slider means and second slider means comprise respective first segments ( 105 ;  106 ) turned towards said open ending parts ( 103 ;  104 ) and second segments ( 205 ;  206 ) fitted coaxially to said first segments ( 105 ;  106 ) turned towards said cap means ( 9 ) and sliding in said second sections ( 3 ″;  4 ″), said first segments ( 105 ;  106 ) of said first and second slider means respectively coinciding with said first and second means for opening/closing said hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ). 
   
   
       110 . The valve according to  claim 109 , wherein said first inlet means comprise a first connection duct ( 121 ) having an ending part leading to said second section ( 3 ″) and an opposite ending part; a first port ( 21 ) which extends from said opposite ending part of said first connection duct ( 121 ) and an opposite opening that can be connected to a supply apparatus ( 23 ) of pressurised fluid, said first outlet means comprising a third duct ( 125 ) having an ending part leading to said second section ( 3 ″) and an opposite ending part; a third port ( 25 ) which extends from said third duct ( 125 ) and an opposite opening that can be connected to a first hydraulic circuit, said second inlet means comprising a second connection duct ( 122 ) having an ending part leading to said second section ( 4 ″) and an opposite ending part; a second port ( 22 ) that extends from said opposite ending part of said second connection duct ( 122 ) and an opposite opening which can be connected to a supply apparatus ( 24 ) of pressurised fluid, said second outlet means comprising a fourth connection duct ( 126 ) having an ending part leading to said second section ( 4 ″) and an opposite ending part; a fourth port ( 26 ) that extends from said fourth connection duct ( 126 ) and an opposite opening which can be connected to a second hydraulic circuit. 
   
   
       111 . The valve according to  claim 109 , wherein said second section ( 3 ″) of said first sliding chamber ( 3 ) further comprises a fifth ring-shaped port ( 27 ) and a seventh ring-shaped port ( 29 ) obtained by said first segment ( 105 ) of said first slider means, said second section ( 4 ″) of said second sliding chamber ( 4 ) further comprising a sixth ring-shaped port ( 28 ) and a eighth ring-shaped port ( 30 ) obtained by said first segment ( 106 ) of said second slider means. 
   
   
       112 . The valve according to  claim 111 , wherein said first segments ( 105 ;  106 ) comprise a respective first ring-shaped groove ( 31 ) and a second ring-shaped groove ( 32 ) arranged to connect said fifth ring-shaped port ( 27 ) or seventh ring-shaped port ( 29 ) and said sixth ring-shaped port ( 28 ) or eighth ring-shaped port ( 30 ). 
   
   
       113 . The valve according to  claim 112 , wherein said second segments ( 205 ;  206 ) respectively comprise a third ring-shaped groove ( 36 ) and a fourth ring-shaped groove ( 37 ) arranged to connect said first duct ( 121 ) to said third duct ( 125 ) and said second duct ( 122 ) to said fourth duct ( 126 ). 
   
   
       114 . The valve according to  claim 113 , wherein said pressure compensation means comprise: a first independent duct ( 38 ) arranged to connect said fifth ring-shaped port ( 27 ) to said second section ( 4 ″) of said second sliding chamber ( 4 ) substantially by said fourth duct ( 126 ); a second independent duct ( 39 ) arranged to connect said sixth ring-shaped port ( 28 ) to said second section ( 3 ″) of said first sliding chamber ( 3 ), substantially by said third duct ( 125 ). 
   
   
       115 . The valve according to  claim 113 , wherein said discharge means comprise: at least one discharge element ( 135 ); a common connection channel ( 235 ) of said discharge element ( 135 ) to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ); first passage offtakes ( 335 ) leaving from said common central channel ( 235 ) connecting it to said first sections ( 3 ′;  4 ′) of said first and second sliding chamber ( 3 ;  4 ); corresponding discharge ducts ( 35 ) leaving from said common central channel ( 235 ) and which connect it to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ) and leading substantially by said first and second ring-shaped groove ( 31 ;  32 ); second offtakes ( 435 ) leaving from said common central channel ( 235 ) and connecting it to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ), leading respectively close to said third ring-shaped groove ( 36 ) and fourth ring-shaped groove ( 37 ). 
   
   
       116 . The valve according to  claim 109 , wherein between said first and second segments ( 105 ,  205 ;  106 ,  206 ) of said first slider means ( 5 ) and second slider means ( 6 ) first chambers ( 40 ;  41 ) with variable volume are defined. 
   
   
       117 . The valve according to  claim 109 , wherein in said first segments ( 105 ;  106 ) are obtained respective lengthwise passages ( 33 ;  34 ) arranged to connect said first ring-shaped groove ( 31 ) to said first chamber ( 40 ) defined between said first segment ( 105 ) and second segment ( 205 ) of said first slider means ( 5 ) and said second ring-shaped groove ( 32 ) to said first chamber ( 41 ) defined between said first segment ( 106 ) and second segment ( 206 ) of said second slider means ( 6 ). 
   
   
       118 . The valve according to  claim 109 , wherein between said cap means and facing ending parts of said second segments ( 205 ;  206 ) are respectively defined a third and a fourth chamber ( 42 ;  43 ) with variable volumes. 
   
   
       119 . The valve according to  claim 117 , wherein between said facing ending parts and said cap means ( 9 ) elastic means ( 46 ) reactive to compression are arranged, said facing ending parts of said second segments ( 205 ;  206 ) shaping further hollow seats ( 44 ;  45 ) arranged to house and contain said flexible means ( 46 ). 
   
   
       120 . The valve according to  claim 119 , wherein in said second segments ( 205 ;  206 ) are obtained respective third ducts ( 47 ;  48 ) having the ending parts leading to said further hollow seats ( 44 ;  45 ) and to said third perimeter groove ( 36 ) and fourth perimeter groove ( 37 ) respectively. 
   
   
       121 . A hydraulic valve suitable for operating brakes of wheels on front axles and brakes of wheels on rear axles of a vehicle, comprising: body means ( 2 ) having first inlet means ( 21 ), second inlet means ( 22 ), first outlet means ( 25 ) and second outlet means ( 26 ); first distributing means ( 5 ) and second distributing means ( 6 ) arranged to connect said first inlet means ( 21 ) to said first outlet means ( 25 ) and second inlet means ( 22 ) to said second outlet means ( 26 ) respectively, first thrust means ( 7 ) and second thrust means ( 8 ) arranged to operate said first distributing means ( 5 ) and second distributing means ( 6 ) respectively, wherein between said first distributing means ( 5 ) and second distributing means ( 6 ) a hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) is provided so that said first distributing means ( 5 ) act on said second distributing means ( 6 ) and vice versa, and wherein said third outlet means ( 145 ) are obtained in said body means ( 2 ) that can be connected to said second inlet means ( 22 ) and fourth outlet means ( 146 ) that can be connected to said first inlet means ( 21 ) in such a way as to selectively operate said brakes on the axles of front wheels. 
   
   
       122 . The valve according to  claim 121 , wherein between said first distributing means ( 5 ) and second distributing means ( 6 ) are interposed respective first and second slider means ( 105 ,  205 ;  106 ,  206 ) for opening/closing said hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) fitted sliding into a first sliding chamber ( 3 ) and into a second sliding chamber ( 4 ) respectively. 
   
   
       123 . The valve according to  claim 122 , wherein said first and second slider means ( 105 ,  205 ;  106 ,  206 ) are operated with said first thrust means ( 7 ) and second thrust means ( 8 ) respectively. 
   
   
       124 . The valve according to  claim 123 , wherein said first slider means and second slider means comprise respective first segments ( 105 ,  106 ) and second segments ( 205 ,  206 ) separate from one another. 
   
   
       125 . The valve according to  claim 124 , wherein between said first segments ( 105 ,  106 ) and second segments ( 205 ,  206 ) a respective first chamber ( 40 ) and a respective second chamber ( 41 ) both with variable volume are defined. 
   
   
       126 . The valve according to  claim 125  wherein said third outlet means ( 145 ) are connected to said first chamber ( 40 ) and said fourth outlet means ( 146 ) are connected to said second chamber ( 41 ). 
   
   
       127 . The valve according to  claim 126 , wherein said third outlet means ( 145 ) are connected to said first chamber ( 40 ) with a fifth duct ( 127 ) and said fourth outlet means ( 146 ) are connected to said second chamber ( 41 ) with a sixth duct ( 128 ). 
   
   
       128 . The valve according to  claim 121 , wherein said first outlet means ( 25 ) and said second outlet means ( 26 ) are hydraulically separate. 
   
   
       129 . The valve according to  claim 121 , wherein said first outlet means ( 25 ) can be connected to a first hydraulic circuit for supplying first user means and said second outlet means ( 26 ) can be connected to a second hydraulic circuit for supplying second user means. 
   
   
       130 . The valve according to  claim 129 , wherein said first user means and second user means respectively comprise a hydraulic circuit for braking a left-hand rear wheel of said vehicle and a hydraulic circuit for braking a right-hand rear wheel of said vehicle. 
   
   
       131 . The valve according to  claim 121 , wherein said first inlet means ( 21 ) and second inlet means ( 22 ) can be connected to respective supply apparatus ( 23 ;  24 ) of pressurised fluid. 
   
   
       132 . The valve according to  claim 121 , wherein between said first outlet means ( 25 ) and second outlet means ( 26 ) are provided pressure compensation means ( 38 ;  39 ) of said pressurised fluid in said hydraulic braking circuit of a left-hand rear wheel and hydraulic braking circuit of a right-hand rear wheel. 
   
   
       133 . The valve according to  claim 121 , wherein said first distributing means comprise: a first sliding chamber ( 3 ) obtained in said body means ( 2 ); first slider means ( 205 ) fitted sliding in said first sliding chamber ( 3 ); first duct means ( 121 ,  125 ) arranged to connect said first sliding chamber ( 3 ) to said first inlet means ( 21 ) and said first outlet means ( 25 ), said first duct means comprising a first duct ( 121 ) arranged to connect said first sliding chamber ( 3 ) to said first inlet means ( 21 ); a third duct ( 125 ) arranged to connect said first sliding chamber ( 3 ) to said first outlet means ( 25 ), said first inlet means ( 21 ) and said first outlet means ( 25 ) being controlled by said first slider means ( 205 ), said second distributing means ( 6 ) comprising: a second sliding chamber ( 4 ) obtained in said body means ( 2 ); second slider means ( 206 ) fitted sliding in said second sliding chamber ( 4 ); second duct means ( 122 ,  126 ) arranged to connect said second sliding chamber ( 4 ) to said second inlet means ( 22 ) and second outlet means ( 26 ), said second duct means comprising: a second duct ( 122 ) arranged to connect said second sliding chamber ( 4 ) to said second inlet means ( 22 ); a fourth duct ( 126 ) arranged to connect said second sliding chamber ( 4 ) to said second outlet means ( 26 ), said second inlet means ( 22 ) and said second outlet means ( 26 ) being controlled by said second slider means ( 206 ). 
   
   
       134 . The valve according to  claim 133 , wherein said second segments ( 205 ,  206 ) have respectively a third perimeter groove ( 36 ) that can be aligned with said first duct ( 121 ) and/or third duct ( 125 ) and a fourth perimeter groove ( 37 ) that can be aligned with said second duct ( 122 ) and/or fourth duct ( 126 ). 
   
   
       135 . The valve according to  claim 122 , wherein said first sliding chamber ( 3 ) and second sliding chamber ( 4 ) are parallel and respectively comprise first sections ( 3 ′;  4 ′) having a first diameter and second sections ( 3 ″;  4 ″) having second diameters smaller than said first diameter, between said first diameter and second diameter being defined ring-shaped connection shoulders ( 300 ). 
   
   
       136 . The valve according to  claim 135 , wherein between said first sections ( 3 ′;  4 ′) and said second sections ( 3 ″;  4 ″) are provided discharge means ( 35 ,  135 ) of said pressurised fluid. 
   
   
       137 . The valve according to  claim 122 , wherein said first sliding chamber ( 3 ) and second sliding chamber ( 4 ) have second concordant ending parts ( 203 ;  204 ) closed with cap means ( 9 ) and corresponding opposite open ending parts ( 103 ;  104 ) for the passage of concurrent ending parts ( 10 ;  11 ) of said first and second distributing means ( 5 ;  6 ), said second sections ( 3 ″;  4 ″) being turned towards said second concordant ending parts ( 203 ;  204 ) and said first sections ( 3 ′;  4 ′) being turned towards said first open ending parts ( 103 ;  104 ). 
   
   
       138 . The valve according to  claim 135 , wherein said first distributing means ( 5 ) and second distributing means ( 6 ) respectively comprise a further first and a further second thrust unit ( 7 ;  8 ) fitted sliding in said first sections ( 3 ′;  4 ′) and placed in axial extension of said first segments ( 105 ,  106 ) and second segments ( 205 ,  206 ) with the interposition of sealing means ( 19 ). 
   
   
       139 . The valve according to  claim 138 , wherein said first and second thrust unit ( 7 ;  8 ) comprise respectively: first push rod elements ( 10 ) and second push rod elements ( 11 ) having corresponding ending parts ( 110 ;  111 ) which extend beyond said opposite first open ending parts ( 103 ;  104 ); elastic means ( 14 ,  15 ,  16 ;  14 ′, 15 ′,  16 ′) reactive to compression placed in between said first push rod element ( 10 ), second push rod element ( 11 ) and said ring-shaped shoulders ( 300 ). 
   
   
       140 . The valve according to  claim 139 , wherein said first push rod element ( 10 ) and second push rod element ( 11 ) comprise respective convex portions ( 110 ;  111 ) protruding towards the outside of said second open ending parts ( 103 ;  104 ) and opposite concave portions ( 210 ;  211 ) facing towards the inside of said first sections ( 3 ′;  4 ′), said convex portions ( 110 ;  111 ) being connectable to respective pedal means ( 12 ;  13 ) that can be operated from the outside. 
   
   
       141 . The valve according to  claim 139 , wherein said first segments ( 105 ;  106 ) are turned towards said open ending parts ( 103 ;  104 ) and said second segments ( 205 ;  206 ) fitted coaxially to said first segments ( 105 ;  106 ) are turned towards said cap means ( 9 ), said first and second means for opening/closing said hydraulic connection ( 36 ,  39 ,  34 ,  41 ;  37 ,  38 ,  33 ,  40 ) comprising said first segments ( 105 ;  106 ). 
   
   
       142 . The valve according to  claim 121 , wherein said first inlet means comprise a first connection duct ( 121 ) having an ending part leading to said second section ( 3 ″) and an opposite ending part; a first port ( 21 ) that extends from said opposite ending part of said first connection duct ( 121 ) and an opposite opening which can be connected to a supply apparatus ( 23 ) of pressurised fluid, said first outlet means comprising a third duct ( 125 ) having an ending part leading to said second section ( 3 ″) and an opposite ending part; a third port ( 25 ) that extends from said third duct ( 125 ) and an opposite opening which can be connected to a first hydraulic circuit, said second inlet means comprising a second connection duct ( 122 ) having an ending part leading to said second section ( 4 ″) and an opposite ending part; a second port ( 22 ) that extends from said opposite ending part of said second connection duct ( 122 ) and an opposite opening which can be connected to a supply apparatus ( 24 ) of pressurised fluid, said second outlet means comprising a fourth connection duct ( 126 ) having an ending part leading to said second section ( 4 ″) and an opposite ending part; a fourth port ( 26 ) that extends from said fourth connection duct ( 126 ) and an opposite opening which can be connected to a second hydraulic circuit. 
   
   
       143 . The valve according to  claim 135 , wherein said second section ( 3 ″) also comprises a fifth ring-shaped port ( 27 ) and a seventh ring-shaped port ( 29 ) obtained by said first segment ( 105 ) and said second section ( 4 ″) also comprises a sixth ring-shaped port ( 28 ) and a eighth ring-shaped port ( 30 ) obtained by said first segment ( 106 ). 
   
   
       144 . The valve according to  claim 143 , wherein said first segments ( 105 ;  106 ) comprise a respective first ring-shaped groove ( 31 ) and a second ring-shaped groove ( 32 ) arranged to connect said fifth ring-shaped port ( 27 ) or seventh ring-shaped port ( 29 ) and said sixth ring-shaped port ( 28 ) or eighth ring-shaped port ( 30 ). 
   
   
       145 . The valve according to  claim 142 , wherein said second segments ( 205 ;  206 ) respectively comprise a third ring-shaped groove ( 36 ) and a fourth ring-shaped groove ( 37 ) arranged to connect said first duct ( 121 ) to said third duct ( 125 ) and said second duct ( 122 ) to said fourth duct ( 126 ). 
   
   
       146 . The valve according to  claim 143 , wherein said pressure compensation means comprise: a first independent duct ( 38 ) arranged to connect said fifth ring-shaped port ( 27 ) to said second section ( 4 ″) substantially by said fourth duct ( 126 ); a second independent duct ( 39 ) arranged to connect said sixth ring-shaped port ( 28 ) to said second section ( 3 ″) substantially by said third duct ( 125 ). 
   
   
       147 . The valve according to  claim 144 , wherein said discharge means comprise: at least one discharge element ( 135 ); a common connection channel ( 235 ) of said discharge element ( 135 ) to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ); first passage offtakes ( 335 ) leaving from said common central channel ( 235 ) connecting it to said first sections ( 3 ′;  4 ′) of said first and second sliding chamber ( 3 ;  4 ); corresponding discharge ducts ( 35 ) leaving from said common central channel ( 235 ) and which connect it to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ) and leading substantially by said first and second ring-shaped groove ( 31 ;  32 ); second offtakes ( 435 ) leaving from said common central channel ( 235 ) and connecting it to said second sections ( 3 ″;  4 ″) of said first and second sliding chamber ( 3 ;  4 ), leading respectively close to said third ring-shaped groove ( 36 ) and fourth ring-shaped groove ( 37 ). 
   
   
       148 . The valve according to  claim 144 , wherein in said first segments ( 105 ;  106 ) are obtained respective lengthwise passages ( 33 ;  34 ) arranged to connect said first ring-shaped groove ( 31 ) to said first chamber ( 40 ) defined between said first segment ( 105 ) and second segment ( 205 ) of said first slider means ( 5 ) and said second ring-shaped groove ( 32 ) to said first chamber ( 41 ) defined between said first segment ( 106 ) and second segment ( 206 ) of said second slider means ( 6 ). 
   
   
       149 . The valve according to  claim 137 , wherein between said cap means ( 9 ) and facing ending parts of said second segments ( 205 ;  206 ) are defined respective second chambers ( 42 ;  43 ) with variable volumes. 
   
   
       150 . The valve according to  claim 149 , wherein between said facing ending parts and said cap means ( 9 ) are placed in elastic means ( 46 ) reactive to compression, said facing ending parts of said second segments ( 205 ;  206 ) shaping further hollow seats ( 44 ;  45 ) arranged to house and contain said elastic means ( 46 ). 
   
   
       151 . The valve according to  claim 150 , wherein in said second segments ( 205 ;  206 ) are obtained respective third ducts ( 47 ;  48 ) having the ending parts leading to said further hollow seats ( 44 ;  45 ) and to said third perimeter groove ( 36 ) and fourth perimeter groove ( 37 ) respectively.