Method for the maintenance of the oil pressure in a circulation lubrication system for highly loaded journal bearings

Claim 2

Method of maintaining the oil pressure in a circulation lubrication system for friction bearings, particularly for the friction bearings in crushing machines in which said circulation lubrication system includes a motor-driven main oil pump and a motor-driven auxiliary oil pump provided with switches controlled by pressure responsive regulators arranged in the oil circulation system, said method comprising the steps of: putting the auxiliary oil pump in operation; putting the main oil pump in operation only after the operating auxiliary oil pump has produced in said oil circulation system a predetermined minimum pressure; subsequently taking said auxiliary oil pump out of operation when the main oil pump has raised the pressure in said oil circulation system to the desired operating pressure; and putting the auxiliary oil pump back into operation and taking the main oil pump out of operation in response to a pressure decrease in said oil circulation system to a predetermined minimum pressure.

Claim 3

Method according to claim 1, including the step of protecting said regulators by means of check valves arranged in the oil lines between said pressure regulators and a common oil supply line leading to said crushing machine and connecting said pressure regulators with the pressure sides of said oil pumps.

Claim 4

In a circulation lubrication system, a motor-driven processing machine, heavy duty friction bearings mounted in said motor-driven processing machine, a pressure line connected to said friction bearings, a main oil pump discharging into said pressure line leading to said friction bearings, another pressure line leading to said friction bearings, an auxiliary oil pump discharging into said other pressure line leading to said friction bearings, an electric motor for each one of said pumps to drive the same, a pressure responsive regulator arranged in each one of said pressure lines, electric circuit means controlled by said pressure responsive regulators of which one when the pressure produced by said auxiliary oil pump reaches a predetermined low value causes said motor-driven processing machine to start and operate, while in response to a somewhat higher minimum value of said oil pressure produced by said auxiliary oil pump said pressure responsive regulator causes the electric circuit of said motor connected with said main oil pump to be closed so that said main oil pump is operated to increase the oil pressure to the prescribed higher operating pressure, the other one of said pressure responsive regulators causing said circuit means to disconnect the motor during operation of said auxiliary oil pump to stop the latter when said main oil pump produces said prescrIbed higher operating pressure.

Claim 5

In a circulation lubrication system, a motor-driven processing machine, heavy duty friction bearings mounted in said motor-driven processing machine, a pressure line connected to said friction bearings, a main oil pump discharging into said pressure line leading to said friction bearings, another pressure line leading to said friction bearings, an auxiliary oil pump discharging into said other pressure line leading to said friction bearings, an electric motor for each one of said pumps to drive the same, a pressure responsive regulator arranged in each one of said pressure lines, electric circuit means controlled by said pressure responsive regulators of which one when the pressure produced by said auxiliary oil pump reaches a predetermined low value causes said motor-driven processing machine to start and operate, while in response to a somewhat higher minimum value of said oil pressure produced by said auxiliary oil pump said pressure responsive regulator causes the electric circuit of said motor connected with said main oil pump to be closed so that said main oil pump is operated to increase the oil pressure to the prescribed higher operating pressure, the other one of said pressure responsive regulators causing said circuit means to disconnect the motor during operation of said auxiliary oil pump to stop the latter when said main oil pump produces said prescrIbed higher operating pressure.

Claim 6

A lubricating system according to claim 3, comprising a common oil supply line connected to said friction bearings and check valves arranged in the oil lines between said pressure regulators and said common oil supply line leading to said processing machine, said pressure regulators connected with the pressure sides of said oil pumps, the pressure regulator connected with said main oil pump being adjusted in such a manner that upon decrease of the operating pressure to a predetermined minimum value the auxiliary oil pump is put into operation.

Claim 7

A lubricating system according to claim 3, comprising a common oil supply line connected to said friction bearings and check valves arranged in the oil lines between said pressure regulators and said common oil supply line leading to said processing machine, said pressure regulators connected with the pressure sides of said oil pumps, the pressure regulator connected with said auxiliary oil pump being adjusted to a pressure which lies below the minimum operating pressure of said auxiliary oil pump and which causes a disconnection of the processing machine.

Claim 8

A lubricating system according to claim 3, comprising a common oil supply line connected to said friction bearings and check valves arranged in the oil lines between said pressure regulators and said common oil supply line leading to said processing machine, said pressure regulators connected with the pressure sides of said oil pumps, the pressure regulator connected with said main oil pump being adjusted in such a manner that upon decrease of the operating pressure to a predetermined minimum value the auxiliary oil pump is put into operation, and a signal device connected to said main oil pump and operated in response to the decrease of pressure to said predetermined minimum value.

Claim 9

A lubricating system according to claim 3, including a signal means connected with said electric circuit means which is caused to be operated by said other pressure responsive means when the oil pressure produced by said main oil pump decreases to a value slightly above said somewhat higher minimum value, whereby at the same time said auxiliary oil pump is again caused to operate and said main oil pump is stopped.