Hydraulic braking apparatus

Claim 2

Hydraulic braking apparatus comprising brake means; at least one brake cylinder member, and a piston member in said cylinder member forming in the same a releasing chamber and a braking chamber, one of said members being movable relative to the other member and connected with said brake means for operating the same between a normal release position and a braking position; a source of pressure fluid; first and second conduit means connecting said source with said releasing and braking chambers, respectively, said first and second conduit means including first and second variable throttling means, respectively; first and second pressure adjusting valve means in said first and second conduit means, respectively, having normal positions in which the pressure in said first conduit means and in said releasing chamber is higher than the pressure in said second conduit means and in said braking chamber so that said movable member holds said brake means in said normal released position, and having operative positions in which the pressure in said second conduit means and in said braking chamber is higher than the pressure in said first conduit means and in said releasing chamber so that said movable member moves said brake means to said braking position; and operator controlled brake actuating means connected with said first and second pressure adjusting valve means and having a normal position for holding said first and second pressure adjusting valve means in said normal positions, and an actuated position for moving said first and second pressure adjusting vaLve means to said operative positions so that said brake means is moved between said normal and braking positions by the pressure differential between said releasing and braking chambers, said brake actuating means operating said first and second variable throttling means to increase and reduce the flow cross-sections of said first and second conduit means when by operation of said valve means, the pressure in the respective conduit means is increased and reduced, respectively.

Claim 3

Hydraulic braking apparatus as claimed in claim 1 and wherein said brake actuating means are connected with said first and second variable throttling means for varying the flow cross section of the same simultaneously with the operation of said first and second pressure adjusting valve means so that in said normal position of said brake actuating means the flow cross section of said first throttling means is greater than the flow cross section of said second throttling means, and so that in said actuated position of said brake actuating means the flow cross section of said second throttling means is greater than the flow cross section of said first throttling means.

Claim 4

Hydraulic braking apparatus as claimed in claim 1 including spring means acting on said movable member to urge the same to move said brake means to said braking position; and wherein the combined spring pressure, and fluid pressure in said braking chamber is less than the fluid pressure in said releasing chamber when said brake actuating means is in said normal position.

Claim 5

Hydraulic braking apparatus as claimed in claim 3 wherein said spring means is located in said braking chamber abutting said cylinder member and piston member.

Claim 6

Hydraulic braking apparatus as claimed in claim 4 wherein said cylinder member is stationary and said piston member is movably mounted in said cylinder member and constitutes said movable member.

Claim 7

Hydraulic braking apparatus as claimed in claim 1 including spring means located in said braking chamber abutting said piston member and said cylinder member for urging said piston member to move said brake means to said braking position; wherein said piston member is said movable member and connected with said brake means; wherein the combined spring pressure and fluid pressure in said braking chamber is less than the fluid pressure in said releasing chamber when said brake actuating means is in said normal position; and wherein said brake actuating means include a brake pedal and a linkage connecting said brake pedal with said first and second pressure adjusting valve means and with said first and second variable throttling means.

Claim 8

Hydraulic braking apparatus as claimed in claim 1, wherein said brake means include a wheel having a cavity with a brake surface, and a brake disk cooperating with said brake surface in said braking position of said brake means and being located in said cavity; said brake disk being connected with said movable member.

Claim 9

Hydraulic braking apparatus comprising brake means; at least one braking cylinder member, and a piston member in said cylinder member forming in the same a releasing chamber and a braking chamber, one of said members being movable relative to the other member and connected with said brake means for operating the same between a normal released position and a braking position; spring means urging said brake means to move to said braking position; a source of pressure fluid including a motor pump connected with said first and second conduit means, and a manually operated pump connected with said releasing chamber for moving said movable member to move said brake means to said normal released position when said motor pump fails; check valve means for separating said manually operated pump from said motor pump; first and second conduit means connecting said source with said releasing and braking chambers, respectively, first and second pressure adjusting valve means in said first and second conduit means, respectively, havinG normal positions in which the pressure in said first conduit means and in said releasing chamber is higher than the pressure in said second conduit means and in said braking chamber so that said movable member holds said brake means in said normal released position, and having operative positions in which the pressure in said second conduit means and in said braking chamber is higher than the pressure in said first conduit means and in said releasing chamber so that said movable member moves said brake means to said braking position; and operator controlled brake actuating means connected with said first and second pressure adjusting valve means and having a normal position for holding said first and second pressure adjusting valve means in said normal positions, and an actuated position for moving said first and second pressure adjusting valve means to said operative positions so that said brake means is moved between said normal and braking positions by the pressure differential between said releasing and braking chambers.

Claim 10

Hydraulic braking apparatus comprising brake means; at least one braking cylinder member, and a piston member in said cylinder member forming in the same a releasing chamber and a braking chamber, one of said members being movable relative to the other member and connected with said brake means for operating the same between a normal released position and a braking position; spring means urging said brake means to move to said braking position; a source of pressure fluid including a motor pump connected with said first and second conduit means, and a manually operated pump connected with said releasing chamber for moving said movable member to move said brake means to said normal released position when said motor pump fails; check valve means for separating said manually operated pump from said motor pump; first and second conduit means connecting said source with said releasing and braking chambers, respectively, first and second pressure adjusting valve means in said first and second conduit means, respectively, havinG normal positions in which the pressure in said first conduit means and in said releasing chamber is higher than the pressure in said second conduit means and in said braking chamber so that said movable member holds said brake means in said normal released position, and having operative positions in which the pressure in said second conduit means and in said braking chamber is higher than the pressure in said first conduit means and in said releasing chamber so that said movable member moves said brake means to said braking position; and operator controlled brake actuating means connected with said first and second pressure adjusting valve means and having a normal position for holding said first and second pressure adjusting valve means in said normal positions, and an actuated position for moving said first and second pressure adjusting valve means to said operative positions so that said brake means is moved between said normal and braking positions by the pressure differential between said releasing and braking chambers.

Claim 11

Hydraulic braking apparatus comprising brake means; at least one brake cylinder member, and a piston member in said cylinder member forming in the same a releasing chamber and a braking chamber, one of said members being movable relative to the other member and connected with said brake means for operating the same between a normal released position and a braking position; a source of pressure fluid; first and second conduit means connecting said source with said releasing and braking chambers, respectively; first and second pressure adjusting valve means in said first and second conduit means, respectively, having normal positions in which the pressure in said first conduit means and in said releasing chamber is higher than the pressure in said second conduit means and in said braking chamber so that said movable member holds said brake means in said normal released position, and having operative positions in which the pressure in said second conduit means and in said braking chamber is higher than the pressure in said first conduit means and in said releasing chamber so that said movable member moves said brake means to said braking position, said first and second pressure adjusting valve means being first and second pressure limiting valves having first and second spring biased valve members, respectively, and first and second actuators for adjusting the spring tension and thereby the pressure limits of said first and second valve members, said first and second actuators being connected with said brake actuating means and operated by the same to vary the pressure maintained in said first and second pressure limiting valve means and in said first and second conduit means, respectively; and operator controlled brake actuating means connected with said first and second pressure adjusting valve means and having a normal position for holding said first and second pressure adjusting valve means in said normal positions, and an actuated position for moving said first and second pressure adjusting value means to said operative positions so that said brake means is moved between said normal and braking positions by the pressure differential between said releasing and braking chambers.

Claim 12

Hydraulic braking apparatus comprising brake means; at least one brake cylinder member, and a piston member in said cylinder member forming in the same a releasing chamber and a braking chamber, one of said members being movable relative to the other member and connected with said brake means for operating the same between a normal released position and a braking position; a source of pressure fluid; first and second conduit means connecting said source with said releasing and braking chambers, respectively; first and second pressure adjusting valve means in said first and second conduit means, respectively, having normal positions in which the pressure in said first conduit means and in said releasing chamber is higher than the pressure in said second conduit means and in said braking chamber so that said movable member holds said brake means in said normal released position, and having operative positions in which the pressure in said second conduit means and in said braking chamber is higher than the pressure in said first conduit means and in said releasing chamber so that said movable member moves said brake means to said braking position, said first and second pressure adjusting valve means being first and second pressure limiting valves having first and second spring biased valve members, respectively, and first and second actuators for adjusting the spring tension and thereby the pressure limits of said first and second valve members, said first and second actuators being connected with said brake actuating means and operated by the same to vary the pressure maintained in said first and second pressure limiting valve means and in said first and second conduit means, respectively; and operator controlled brake actuating means connected with said first and second pressure adjusting valve means and having a normal position for holding said first and second pressure adjusting valve means in said normal positions, and an actuated position for moving said first and second pressure adjusting value means to said operative positions so that said brake means is moved between said normal and braking positions by the pressure differential between said releasing and braking chambers.