GB1570009A - Lubricating systems - Google Patents

Description

(54) LUBRICATING SYSTEMS (71) We, DENCO FARVAL LI MITED, of P.O. Box 11, Holmer Road, Hereford, HR4 9SJ, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to lubricating systems.

In certain applications, it is desirable to dispense lubricant in controlled metered quantities, and for this purpose one known form of metering valve, described in Patent Specification No. 513,388, comprises a rotary valve element rotatable between two positions and at least one double-acting piston adapted to dispense a pre-determined quantity of lubricant from a pressurised source upon each rotation of the element between said positions. The metering valve is generally provided with a handle for rotating the element, and means for temporary or permanent connection to a pressurised lubricant source.

There is a requirement for a lubricating system where metered quantities of lubricant can be dispensed by such a metering valve automatically at regular intervals.

Such a requirement exists for example in the case of a rotary plug valve provided at the base of a coal hopper. Each time the valve is opened to allow coal to pass out of the hopper and subsequently closed, the sliding surfaces of the valve become contaminated with the coal. and to avoid seizing-up a regular periodic injection of metered quantities of lubricant is desirable during periods when the valve is open.

The present invention provides a lubrication system for dispensing metered quantities of lubricant at regular intervals comprising pumping means for supplying pressurised lubricant, a metering valve having a rotary valve element rotatable between two positions and at least one double acting piston adapted to dispense a metered quantity of lubricant supplied by said pumping means upon each rotation of the element between said positions, and drive means adapted to reciprocate said valve element between said positions at regular intervals.

Preferably, a pressure regulator is provided between the pumping means and the metering valve so that lubricant is supplied at a suitable pressure for operation of the valve. The metering valve thereby operates in a more satisfactory manner.

In the case of the plug valve mentioned above, the output of the metering valve can be connected to the plug valve and the drive means automatically controlled so that each time the plug valve is opened, metered quantities of lubricant are dispensed periodically until the plug valve is closed.

Preferably a number of metering valves, which may be arranged in units with a common valve element. are arranged to supply lubricant to different parts of the plug valve through passages in the plug valve element.

The drive means may take the form of an electric motor whose armature is arranged to reciprocate periodically through an appropriate angle as long as current is supplied and is connected to the valve element of the metering valve or valves.

Two units of metering valves may be arranged one on each side of the motor and connected to respective ends of the armature shaft.

The invention will now be more particularly described. by way of example only, with reference to the accompanying drawings, in which: Figure 1 is an overall diagrammatic view of a lubricating system according to the invention; Figure 2 is a diagrammatic sectional view showing a pressure regulator of the system; and Figures 3 and 4 are diagrammatic sectional views of a metering valve of the system.

Referring to Figure 1, pumping means, e.g. in the form of an air operated pump 1 controlled from a panel 2 and operating on a pressure stalling basis, supplies pressurized lubricant, e.g. grease, from a drum 3 to a line 4.

A pressure regulator 5 is provided in the line 4 to control the pressure of the lubricant. which may typically be supplied by the pump 1 at about 100 bars and be reduced by the regulator to 5 to 40 bars, this being a suitable pressure for metering valve units 6 which are supplied by the line 4.

Each unit 6 has a number, e.g. four, of double-acting pistons and a common rotary valve element connected to the armature shaft of an electric motor 7. The double acting pistons are arranged to dispense metered quantities of lubricant upon each 90" rotation of the valve elements between their two limiting positions, and the motor 7 is thus arranged to rotate back and forth through 9() so long as current is supplied.

Each unit 6 supplies eight lines 8 which are connected to passages in the valve element of a plug valve 9 of a coal hopper. and the motor 8 is supplied with current during periods when the plug valve 9 is open. so that lubricant is concomitantly supplied to the plug valve.

Referring to Figure 2, the pressure regulator 5 may be seen to comprise a housing 10 with a transverse passage 11 for lubricant from the line 4. A first bore 12 extends at right-angles to the passage 11 and houses a cylindrical valve element or pin 13 with an opening 14 which registers with the passage 11 to permit flow of lubricant therethrough.

A feed-back passage 15 leads from the passage 11 on the outlet side of the regulator to a cylinder or second bore 16 coaxial with the first bore and housing a piston 17. The piston is urged by the lubricant pressure in the passage 15 against the force of a compression spring 18 located in a third bore 19 disposed coaxially above the first bore 12. The force of the compression spring 18 may be adjusted by means of a screw-cap 20 to control the output pressure of the regulator. If the pressure exceeds the set value, the piston 17 is moved up against the spring 18 so that the opening 14 in the pin 13 comes out of register with the passage 11, and no further lubricant is allowed to pass. The output pressure thus drops and allows the piston to revert to its working position in which the opening 14 again registers with the passage 11.

The operation of the metering valve units 6 is shown in Figures 3 and 4. The units. sold under the trade name "Multival". and described in Patent Specification No.

513,388, comprise a number, e.g. four, of double acting pistons 21 in cylinders 22 in a common block 23. A common rotary cylindrical valve element 24 extends through the block 23 at right angles to the cylinders 22.

Lubricant is supplied to the unit through an inlet 25 leading to an annular groove (not shown) on the element 24 in communication with a longitudinal passage 26 in the element 24. In line with each piston 21, the passage 26 has a port which can be aligned with upper or lower inclined passages 27 and 28 respectively according to which of two angular positions differing by 90" the valve element assumes. the upper passage 27 leads to a space in the cylinder 22 above the piston 21. and the lower passage 28 to a space below the piston 21.

Also in line with each piston 21 is a diametral passage 29 in the valve element, disposed at 90" to the port in passage 26, and arranged to connect whichever passage 27 or 28 is not in line with the port to a respective outlet 30 or 31.

When the valve element 24 is rotated to the position shown in Figure 3, lubricant from inlet 25 and passage 26 flows through passage 27 to cylinder 22 and moves the piston 21 down. thus discharging a metered quantity of lubricant through passages 28 and 29 to outlet 31. Rotation of the element to its other position shown in Figure 4 allows lubricant to flow from inlet 25 and passage 26 through passage 28 and move the piston 21 back up. Thereby a further metered quantity of lubricant is discharged through passages 27 and 29 to outlet 30.

An indicator rod 32 is connected to each piston 21 and is visible through an opening in a valve cap 33 to provide visual checking of valve operation. The stroke of piston 21 and hence the quantity of lubricant dispensed is adjustable by means of a screw 34 in the valve cap 33.

WHAT WE CLAIM IS: 1. A lubrication system for dispensing metered quantities of lubricant at regular intervals. comprising pumping means for supplying pressurized lubricant, a metering valve having a rotary valve element rotatable between two positions, and at least one double-acting piston adapted to dispense a metered quantity of lubricant supplied by said pumping means upon each rotation of the element between said positions, and drive means adapted to reciprocate said valve element between said positions at regular intervals.

2. A lubrication system as claimed in claim 1. wherein a pressure regulator is provided between the pumping means and the metering valve for regulating the pressure of the lubricant supplied to the valve.

3. A lubrication system as claimed in claim 1 or claim 2, wherein a plurality of

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. and Figures 3 and 4 are diagrammatic sectional views of a metering valve of the system. Referring to Figure 1, pumping means, e.g. in the form of an air operated pump 1 controlled from a panel 2 and operating on a pressure stalling basis, supplies pressurized lubricant, e.g. grease, from a drum 3 to a line 4. A pressure regulator 5 is provided in the line 4 to control the pressure of the lubricant. which may typically be supplied by the pump 1 at about 100 bars and be reduced by the regulator to 5 to 40 bars, this being a suitable pressure for metering valve units 6 which are supplied by the line 4. Each unit 6 has a number, e.g. four, of double-acting pistons and a common rotary valve element connected to the armature shaft of an electric motor 7. The double acting pistons are arranged to dispense metered quantities of lubricant upon each 90" rotation of the valve elements between their two limiting positions, and the motor 7 is thus arranged to rotate back and forth through 9() so long as current is supplied. Each unit 6 supplies eight lines 8 which are connected to passages in the valve element of a plug valve 9 of a coal hopper. and the motor 8 is supplied with current during periods when the plug valve 9 is open. so that lubricant is concomitantly supplied to the plug valve. Referring to Figure 2, the pressure regulator 5 may be seen to comprise a housing 10 with a transverse passage 11 for lubricant from the line 4. A first bore 12 extends at right-angles to the passage 11 and houses a cylindrical valve element or pin 13 with an opening 14 which registers with the passage 11 to permit flow of lubricant therethrough. A feed-back passage 15 leads from the passage 11 on the outlet side of the regulator to a cylinder or second bore 16 coaxial with the first bore and housing a piston 17. The piston is urged by the lubricant pressure in the passage 15 against the force of a compression spring 18 located in a third bore 19 disposed coaxially above the first bore 12. The force of the compression spring 18 may be adjusted by means of a screw-cap 20 to control the output pressure of the regulator. If the pressure exceeds the set value, the piston 17 is moved up against the spring 18 so that the opening 14 in the pin 13 comes out of register with the passage 11, and no further lubricant is allowed to pass. The output pressure thus drops and allows the piston to revert to its working position in which the opening 14 again registers with the passage 11. The operation of the metering valve units 6 is shown in Figures 3 and 4. The units. sold under the trade name "Multival". and described in Patent Specification No. 513,388, comprise a number, e.g. four, of double acting pistons 21 in cylinders 22 in a common block 23. A common rotary cylindrical valve element 24 extends through the block 23 at right angles to the cylinders 22. Lubricant is supplied to the unit through an inlet 25 leading to an annular groove (not shown) on the element 24 in communication with a longitudinal passage 26 in the element 24. In line with each piston 21, the passage 26 has a port which can be aligned with upper or lower inclined passages 27 and 28 respectively according to which of two angular positions differing by 90" the valve element assumes. the upper passage 27 leads to a space in the cylinder 22 above the piston 21. and the lower passage 28 to a space below the piston 21. Also in line with each piston 21 is a diametral passage 29 in the valve element, disposed at 90" to the port in passage 26, and arranged to connect whichever passage 27 or 28 is not in line with the port to a respective outlet 30 or 31. When the valve element 24 is rotated to the position shown in Figure 3, lubricant from inlet 25 and passage 26 flows through passage 27 to cylinder 22 and moves the piston 21 down. thus discharging a metered quantity of lubricant through passages 28 and 29 to outlet 31. Rotation of the element to its other position shown in Figure 4 allows lubricant to flow from inlet 25 and passage 26 through passage 28 and move the piston 21 back up. Thereby a further metered quantity of lubricant is discharged through passages 27 and 29 to outlet 30. An indicator rod 32 is connected to each piston 21 and is visible through an opening in a valve cap 33 to provide visual checking of valve operation. The stroke of piston 21 and hence the quantity of lubricant dispensed is adjustable by means of a screw 34 in the valve cap 33. WHAT WE CLAIM IS:

1. A lubrication system for dispensing metered quantities of lubricant at regular intervals. comprising pumping means for supplying pressurized lubricant, a metering valve having a rotary valve element rotatable between two positions, and at least one double-acting piston adapted to dispense a metered quantity of lubricant supplied by said pumping means upon each rotation of the element between said positions, and drive means adapted to reciprocate said valve element between said positions at regular intervals.

2. A lubrication system as claimed in claim 1. wherein a pressure regulator is provided between the pumping means and the metering valve for regulating the pressure of the lubricant supplied to the valve.

3. A lubrication system as claimed in claim 1 or claim 2, wherein a plurality of

metering valves are arranged in units with a common valve element, the valves being arranged to supply lubricant to different locations.

4. A lubrication system as claimed in any preceding claim, wherein the drive means comprises an electric motor having an armature arranged to reciprocate periodically through an appropriate angle as long as current is supplied, the armature being connected to the valve element of the metering valve.

5. A lubrication system as claimed in claim 4, wherein two units of metering valves are arranged one on each side of the motor, the valve element of both units being connected to respective ends of the armature.

6. A lubrication system substantially as herein described with reference to the accompanying drawing.