Lubrication – Systems
Reexamination Certificate
1999-10-12
2001-03-20
Marmor, Charles A (Department: 3681)
Lubrication
Systems
C056S012300, C060S494000, C417S326000
Reexamination Certificate
active
06202790
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates, generally, to lubrication systems for mechanical devices and more particularly, to a lubrication method and system which permits pumping lubricant, at different speeds, to an attachment coupled to a work vehicle or to pump lubricant to a reservoir on the work vehicle.
BACKGROUND OF THE INVENTION
Work vehicles, such as tractors, combines, and cotton harvesters, typically include or are coupled to various rotatably driven mechanisms for performing various functions. Such attachments typically require lubrication to facilitate their operation by reducing friction and wear of the various parts and components of such attachments.
For instance, a cotton harvester is provided with a number of harvesting units mounted, typically, at the front end of the harvester. Each harvesting unit has a rotatable harvesting mechanism which has individual lubricant or lubricant fittings to supply lubricant to the various picker bars, spindles, cam followers and drive shafts extending through the harvester unit. A drive gear arrangement located in the top of the harvester unit transmits power from a drive shaft to the drum and spindles. Each of these components require lubrication to operate properly and efficiently. Modern cotton harvesters can have as many as eight (8) row harvesting units mounted on the cotton harvester with each requiring lubrication as described above.
Several systems have been developed to provide lubricant to such attachments as described in U.S. Pat. No. 4,769,978 (issued to Reichen, et al.) which discloses a system requiring a pump to move lubricant from a reservoir to cotton harvesting drums and a separate additional pump for filling the reservoir with lubricant as the lubricant is used. Another approach is disclosed in U.S. Pat. No. 5,099,955 (assigned to the assignee of the present invention) which uses a single pump to move lubricant from a reservoir on an attachment to the cotton harvesting drums and it uses the same pump to fill the reservoir on the attachment from a source of lubricant, with the flow at the same rate in both directions. Filling the lubricant reservoir at the same rate of flow at which the lubricant is used by the attachment takes more time than desired by the operator. Using an additional pump is expensive and troublesome since a separate power supply is needed to operate the second pump. This latter system utilizes a plurality of valves to affect the directional change of the lubricant flow. The two systems described require multiple valves or multiple pumps operating at the same flow rates to move the lubricant as needed.
Thus, there remains a need to provide a lubrication system that can utilize a single pump for moving lubricant from a source of lubricant to fill a reservoir and to use the same pump to move lubricant from the reservoir to an attachment using such lubricant. There is also a need for providing a variation in the flow rates when the system is in the lubrication using mode, i.e., slow verses the lubrication fill mode, i.e., fast. It would also be advantageous to affect such transition between a lubrication mode to a fill mode with a minimum of valves.
SUMMARY OF THE INVENTION
The present invention provides a lubrication system for a work vehicle having a lubricant reservoir and a lubricant using attachment that comprises a bi-directional pump operatively connected to a bi-directional hydraulic motor as a pump-motor set. The pump is in fluid communication with the reservoir, the lubricant using attachment and a lubricant fill connector. A pair of flow limiting devices, which devices can be a fixed rate or a multiple flow rate, are in fluid communication with the bi-directional hydraulic motor to selectively regulate the speed of the motor. A single three position/four-way control valve is in fluid communication with each flow limiting device and a source of hydraulic fluid. The source of hydraulic fluid typically is already located on the work vehicle to which the lubricant using attachment is coupled. The control valve has an off position which prevents lubricant from moving in the system and a first position which facilitates fluid communication with the bi-directional hydraulic motor through one flow limiting device for operation of the bi-directional pump in a lubricant using attachment mode. The rate of flow of such flow limiting device can be within the range of between 0.5 gallons and 1.5 gallons per minute with the preferred embodiment having a flow rate of about one gallon per minute. A second position of the control valve facilitates fluid communication with the bi-directional hydraulic motor through the other flow limiting device for operation of the bi-directional pump in a lubricant reservoir fill mode. This flow limiting device typically is set between a range of zero and seven gallons per minute with the preferred embodiment having a flow rate of about six gallons per minute. The present invention allows a single hydraulic pump to be used at a faster rate of operation in the fill mode than the rate of flow in the lubrication use mode. The flow limiting devices can be either a fixed flow rate device or a multiple flow rate device as selected by an operator of the work vehicle which utilizes the present invention. The various positions of the control valve can be actuated by a solenoid, a hydraulic cylinder, a pneumatic cylinder or a cable, all of which can be operated from the cab of the work vehicle.
The present invention also presents a method for pumping lubrication, at different speeds, in one of a use mode and a fill mode for a work vehicle having a lubricant reservoir and a lubricant using attachment comprising the steps of providing a bi-directional pump in fluid communication with the reservoir, the attachment and a lubricant fill connector, with the pump connected to a hydraulic motor. The method also includes providing a pair of flow limiting devices in fluid communication with the motor as well as a control valve, with the control valve also in fluid communication with a source of hydraulic fluid. By moving the control valve to a first position the motor moves the pump in a direction that corresponds to a use mode to provide lubricant from the reservoir to the attachment. Moving the control valve to a second position facilitates the motor moving the pump in a fill mode to provide lubricant from a lubricant supply through the lubricant fill connector to the lubricant reservoir thereby filling the lubricant reservoir. The operator of the work vehicle selects the flow rates of the flow limiting device such that the fill mode is faster than the use mode. The operator can also move the control valve to an off position when the pump is not needed to pump lubricant. The operator of the work vehicle can move the control valve by operating an actuator which is operatively connected to the control valve.
Other features and advantages of the present invention will become readily apparent from the following detailed description, appended drawings and accompanying claims.
REFERENCES:
patent: 2232428 (1941-02-01), Benedek
patent: 2961829 (1960-11-01), Weisenbach
patent: 3258022 (1966-06-01), Thompson
patent: 3300969 (1967-01-01), Barden
patent: 3901032 (1975-08-01), Steiger et al.
patent: 4531368 (1985-07-01), Killen
patent: 4769978 (1988-09-01), Reichen et al.
patent: 4840018 (1989-06-01), Deutsch
patent: 4972663 (1990-11-01), Richman et al.
patent: 5018343 (1991-05-01), Finke
patent: 5099955 (1992-03-01), Mangen et al.
patent: 5137117 (1992-08-01), Mangen et al.
patent: 5390762 (1995-02-01), Nelson
Case Corporation
Foley & Lardner
Marmor Charles A
Parekh Ankur
LandOfFree
Multiple speed lubrication system for a work vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multiple speed lubrication system for a work vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multiple speed lubrication system for a work vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498062