Integrated flow divider circuit

Claim 2

An integrated flow divider circuit for dividing flow to a plurality of motors comprising, a flow divider valve having a chamber with a pair of outlets leading respectively to a pair of motors, a pair of inlet lines to said flow divider having branch lines leading to opposite ends of said chamber, a spool valve in said chamber responsive to pressure in said branch lines to position the spool valve relative to said outlets to balance the pressure in said branch lines, and a variable orifice in each of said inlet lines to establish a pressure differential and responsive to pressure changes upstream of said orifice to minimize the change in pressure differential in response to changes in flow.

Claim 3

An integrated flow divider circuit as defined in claim 1 including means for bypassing said flow divider valve to connect each of said motors directly to the inlet lines.

Claim 4

An integrated flow divider circuit as defined in claim 2 wherein said bypassing means included means to bypass said flow divider valve when flow through the motors is reversed.

Claim 5

An integrated flow divider circuit as defined in claim 3 wherein said bypass means comprises a check valve connected between an inlet line and an outlet line in parallel with one of said flow divider valves and spring-urged to a closed position, means for applying inlet pressure to said check valve to maintain it closed when the motors are operated in forward direction through the flow divider valve, and passages leading to the check valve to open the check valve when the motors are operating in reverse or when the motors are to operate independently.

Claim 6

An integrated flow divider circuit as defined in claim 1 wherein said variable orifice in each of said lines comprises a valve located in a bore terminating in a cross passage defining a metering shoulder with the cross passage connected to both of said inlet lines, spring means urging said valve into said bore against inlet pressure in the bore to set the pressure differential, inlet pressure urging the valve out of the bore to define a metering orifice between the valve and the shoulder, and a surface on said valve responsive to pressure in the cross passage resulting from motor reversal to move the valve into the bore and fully close the bore.

Claim 7

An integrated flow divider circuit for dividing fluid flow between three or more fluid motors including a first divider circuit with a flow divider valve having a chamber with a pair of outlets one of which supplies one or more motors with the other outlet connected to a second divider circuit, a pair of inlet lines to said flow divider valve chamber having branch lines leading to opposite ends of said chamber, a spool valve in said chamber responsive to pressure in said branch lines to position the spool valve relative to said outlets to balance the pressure in said branch lines, the other of said outlets branching into a pair of inlet passages for a second flow divider valve in the second divider circuit and having a pair of outlet passages for a pair of motors.

Claim 8

An integrated flow divider circuit for dividing fluid flow between three or more fluid motors including a first divider circuit with a flow divider valve having a chamber with a pair of outlets one of which supplies one or more motors with the other outlet connected to a second divider circuit, a pair of inlet lines to said flow divider valve chamber having branch lines leading to opposite ends of said chamber, a spool valve in said chamber responsive to pressure in said branch lines to position the spool valve relative to said outlets to balance the pressure in said branch lines, the other of said outlets branching into a pair of inlet passages for a second flow divider valve in the second divider circuit and having a pair of outlet passages for a pair of motors.

Claim 9

An integrated flow divider circuit as defined in claim 6 wherein the second flow divider valve is responsive to pressures in the outlet passages to balance the pressures in the inlet passages to the second flow divider valve.

Claim 10

An integrated flow divider circuit as defined in claIm 6 wherein each of said inlet lines and inlet passages has a variable orifice device responsive to change in flow to minimize the change in pressure differential in response to change in flow.

Claim 11

An integrated flow divider circuit as defined in claim 6 including a plurality of check valves, and means placing said check valves in circuit with said flow divider valves to bypass said flow divider valves on reverse operation of said motors, and means operable to open said check valves to bypass said flow divider valves when the motors are to operate independently.

Claim 12

A control circuit for a plurality of fluid motors having reversible fluid flow therethrough, a primary flow divider circuit having a flow divider valve with a chamber having a pair of inlet lines connected to a fluid pressure source, a pair of outlet passages from said chamber connected one to each of a pair of motors, a spool valve in said chamber with a pair of lands movable relative to said outlet passages to provide variable pressure drops, a pair of branch lines leading from said inlet lines to the ends of said chamber to position said spool to maintain equal pressures on both ends of said spool, and means for automatically bypassing said flow divider circuit when the fluid flow to the motors is reversed.

Claim 13

A control circuit for a plurality of fluid motors having reversible fluid flow therethrough, a primary flow divider circuit having a flow divider valve with a chamber having a pair of inlet lines connected to a fluid pressure source, a pair of outlet passages from said chamber connected one to each of a pair of motors, a spool valve in said chamber with a pair of lands movable relative to said outlet passages to provide variable pressure drops, a pair of branch lines leading from said inlet lines to the ends of said chamber to position said spool to maintain equal pressures on both ends of said spool, and means for automatically bypassing said flow divider circuit when the fluid flow to the motors is reversed.

Claim 14

A control circuit as defined in claim 10 including means to bypass said flow divider circuit when said motors are to be driven independently of each other

Claim 15

An integrated flow divider circuit for dividing fluid flow between three or more fluid motors including a first divider circuit with a flow divider valve having a chamber with a pair of outlets one of which supplies one or more motors with the other outlet connected to a second divider circuit, a pair of inlet lines to said flow divider valve chamber having branch lines leading to opposite ends of said chamber, a spool valve in said chamber responsive to pressure in said branch lines to position the spool valve relative to said outlets to balance the pressure in said branch lines, the other of said outlets branching into a pair of inlet passages for a second flow divider valve in the second divider circuit and having a pair of outlet passages for a second and third motor, and a variable orifice means in each of said inlet lines responsive to change in flow to minimize the change in pressure differential with the orifice in the inlet line supplying the other of said outlets having a size relative to the orifice in the other inlet line which is in direct ratio to the number of motors supplied by said one outlet.

Claim 16

An integrated flow divider circuit for dividing fluid flow between three or more fluid motors including a first divider circuit with a flow divider valve having a chamber with a pair of outlets one of which supplies one or more motors with the other outlet connected to a second divider circuit, a pair of inlet lines to said flow divider valve chamber having branch lines leading to opposite ends of said chamber, a spool valve in said chamber responsive to pressure in said branch lines to position the spool valve relative to said outlets to balance the pressure in said branch lines, the other of said outlets branching into a pair of inlet passages for a second flow divider valve in the second divider circuit and having a pair of outlet passages for a second and third motor, and a variable orifice means in each of said inlet lines responsive to change in flow to minimize the change in pressure differential with the orifice in the inlet line supplying the other of said outlets having a size relative to the orifice in the other inlet line which is in direct ratio to the number of motors supplied by said one outlet.

Claim 17

A circuit as defined in claim 12 wherein said variable orifice devices comprise a single valve in communication with both of said inlet lines.

Claim 18

An integrated flow divider circuit as defined in claim 15 wherein said variable orifice means in each of said inlet lines comprises a single valve member located in a bore terminating in a cross passage defining a metering shoulder with the cross passage connected to both of said inlet lines, said single valve member having an annular wall with an elongate slot facing the inlet line supplying a single motor and slot means in the wall having a different width than the elongate slot facing the other inlet line, spring means urging said valve into said bore against inlet pressure in the bore set the pressure differential, inlet pressure urging the valve out of the bore to define metering orifices between the single valve member slot and slot means and the shoulder, and a surface on said valve responsive to pressure in the cross passage resulting from motor reversal to move the valve into the bore and fully close the bore.