Patent Application
20180320337
The present disclosure relates generally to slewing systems. More specifically, the present disclosure relates to slewing assist systems for operation with heavy equipment for mining, excavating, and construction etc.
Machines, such as excavators and power shovels, may include a deck or other platform that rotates above continuous tracks, wheels, pontoons, etc. Extending from the deck, the machine may further include a boom for an articulated arm or crane designed to operate a bucket, a breaker, a hook, or any other such work tool. Accordingly, such machines typically include one or more actuators designed to move the tracks, rotate the deck, and operate the articulated arm and work tool.
By way of example, an excavator or power shovel may typically operate in work cycles which may include digging, lifting, swinging, dumping, and returning steps for operating a bucket to dig and load fragmented rock, earth, minerals, overburden, and the like for mining or construction purposes. The operation of rotating the deck of the machine is generally powered by a motor or other such means. Most of the time the motor or such means are designed oversized to make the machine capable of operating under heavy loads. Other requirements may include making an existing or older machine handle operations like dredging, or any other such operation requiring to rotate the deck under heavy load on the bucket. Thus, the machine operates with a motor that is oversized for majority of its power demand profile. The oversized motor affects initial purchasing cost, operating and repairing costs, and any probability of retrofitting the existing or older machines to handle dredging operations.
G.B. Patent No. 8,198,64A (hereinafter referred to as '864 reference) describes a slewing motor for jibbed machines like cranes, excavators, etc. The '864 reference includes a pinion secured to a slewing part of the machine and a circular rack secured to a stationary part. The motion is provided by controlling valves providing operating fluid. However, the '864 reference does not disclose details about any solution for reduction in motor size or retrofitting older machines for dredging like operations.
Therefore, an improved slewing system for the machine is required.
In an aspect of the present disclosure, a slewing assist system for a machine is provided. The machine includes an upper body structure supported on an undercarriage structure such that the upper body structure swings about the undercarriage structure. The slewing assist system includes a central rotation member coupled to the undercarriage structure. The central rotation member rotates with the undercarriage structure. A slip member is concentrically coupled to the central rotation member. The slip member is adapted to allow a rotational motion of the central rotation member relative to the slip member. At least one pin is coupled to the slip member. The at least one pin movable between a retracted position and an expanded position. The at least one pin engages the slip member with the central rotation member in the expanded position such that the central rotation member and the slip member rotate together. A lever arm is fixedly coupled to the slip member. A first end and a second end of an actuating element are coupled to the lever arm and the upper structure. The slewing assist system provides additional slewing assist to the upper body structure through the lever arm by engaging the slip member and the central rotation member through the at least one pin. The second end of the actuating element is extended to assist in a first rotational direction, and is retracted to assist in a second rotational direction.
In another aspect of the present disclosure, a slewing assist system for a machine is provided. The machine has an upper body structure supported on an undercarriage structure such that the upper body structure swings about the undercarriage structure. The slewing assist system includes a central rotation member coupled to the undercarriage structure such that the central rotation member rotates with the undercarriage structure. A slip member concentrically coupled to the central rotation member, and is adapted to allow a rotational motion of the central rotation member relative to the slip member. At least one pin movable between a retracted position and an expanded position is coupled to the slip member. The at least one pin engages the slip member with the central rotation member in the expanded position such that the central rotation member and the slip member rotate together. A lever arm is fixedly coupled to the slip member. An actuating element has a first end coupled to the lever arm and a second end coupled to the upper structure. A controller is communicably coupled to the slip member, the at least one pin, and the actuating element. The controller provides additional slewing assist to the upper body structure through the lever arm by engaging the slip member and the central rotation member through the at least one pin. The second end of the actuating element is extended to assist in a first rotational direction, and retracted to assist in a second rotational direction.
In yet another aspect of the present disclosure, a machine is provided. The machine includes an upper body structure supported on the undercarriage structure such that the upper body structure swings about the undercarriage structure. A slew gear assembly coupled to the upper body structure. A slew drive is coupled to the slew gear assembly. The slew drive drives the slew gear assembly to swing the upper body structure relative to the undercarriage structure. A slewing assist system is coupled to the undercarriage structure and the upper body structure. The slewing assist system includes a central rotation member coupled to the undercarriage structure such that the central rotation member rotates with the undercarriage structure. A slip member is concentrically coupled to the central rotation member and is adapted to allow a rotational motion of the central rotation member relative to the slip member. At least one pin coupled to the slip member and movable between a retracted position and an expanded position. The at least one pin engages the slip member with the central rotation member in the expanded position such that the central rotation member and the slip member rotate together. A lever arm is fixedly coupled to the slip member. A first end of an actuating element is coupled to the lever arm, and a second end of the actuating element is coupled to the upper structure. The slewing assist system provides additional slewing assist to the upper body structure through the lever arm by engaging the slip member and the central rotation member through the at least one pin. The second end of the actuating element is extended to assist in a first rotational direction, and retracted to assist in a second rotational direction.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to same or like parts.
The machine 100 includes an upper body structure 102 supported on an undercarriage structure 104. Although, the undercarriage structure 104 is illustrated as continuous tracks, it should be contemplated that the undercarriage structure 104 may be any other type of ground engaging element as well, for example, wheels etc. The upper body structure 102 swings about the undercarriage structure 104 defining a slewing movement. The upper body structure 102 includes an engine compartment 106 and an operator cabin 108. The machine 100 also includes a work tool 110 having a boom 112 operably coupled to an arm 114 for operating a bucket 116.
Further referring to
The slewing assist system 204 further includes a slip member 210 concentrically coupled to the central rotation member 206. The slip member 210 is adapted to allow a rotational motion of the central rotation member 206 relative to the slip member 210. In some embodiments, the slip member 210 may be a bearing-like element with proper lubrication to allow the rotational motion of the central rotation member 206. A pin 212 is coupled to the slip member 210. The pin 212 may be coupled to the slip member 210 by any suitable joining mechanism which may be suitable as per the need of the present disclosure.
As shown in
The pin 212 of the slewing assist system 204 is movable between an expanded position and a retracted position.
Now referring to
As depicted in the
The controller 600 may control the actuation of the first pin 500 and the second pin 502 between the retracted position and the expanded position. In some embodiments, the controller 600 may control the actuation of the first pin 500 and the second pin 502 between the retracted position and the expanded position based on at least one of a bucket load, an engine load, an operator command, and a rotational speed of the upper body structure 102. The controller 600 may further utilize any other such parameters as well to control the actuation of the first pin 500 and the second pin 502 based on application requirements. The present disclosure, in any manner, is not limited by the parameters being used by the controller 600 to control the motion of the first pin 500 and the second pin 502.
The present disclosure provides a slewing assist system 204 associated with the machine 100. In an embodiment, the machine 100 is switched on and is operating to excavate underwater or in other such conditions requiring the additional assist for the slewing movement. In some embodiments, the operator is operating the bucket 116 and giving the slewing movement to the upper body structure 102 by operating the slew drive 202. The slew drive 202 rotates the slew gear assembly 200, which in turn provides the slewing movement to the upper body structure 102. In some embodiments, the operator may operate the undercarriage structure 104 of the machine 100 as well.
The machine 100 may be provided the additional assist by using the slewing assist system 204. In some embodiments, the controller 600 may receive data about a bucket load from the bucket 116. In other embodiments, the controller 600 may receive data from the slew drive 202 about the resistance or load during the slewing movement of the machine 100. In some embodiments, the undercarriage structure 104 may provide data about the ground environment or material in which the machine 100 is operating by a traction sensor (not shown) mounted on the undercarriage structure 104, or any other suitable place on the machine 100. Data about the engine load or the rotational speed of the upper body structure 102 may be other relevant parameters for providing the additional assist.
The controller 600 may decide to provide the additional assist based on the above parameters, or after receiving an express command from the operator. In some embodiments, the controller 600 may actuate the first pin 500 and the second pin 502. In other embodiments, the controller 600 actuates the pin 212. The controller 600 then may actuate the actuating element 302 by providing the fluid in the first inlet 400 or the second inlet 402, based on the requirement of providing additional assist in a particular rotational direction (AA′ or BB′). The second end 306 may extend or retract based on the above actuation by the controller 600.
The slewing assist system 204 of the present disclosure provides additional assist only when required, and thus prevents the need for having the slew drive 202 designed for higher power than required by the present system design requirements of the machine 100, eliminating very high initial capital costs. Further, the overall size of the slew drive 202 may be much smaller in comparison due to the lower power requirements, providing better efficiency. The slewing assist drive 204 of the present disclosure may also be beneficial in cases where existing or older machines have to be used for dredging or other such operations. The slewing assist drive 204 may be retrofitted in the existing or older machines, making them useful for handling more tasks requiring heavy slewing movements.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
