Patent Application
20140175773
The present disclosure relates to a flow rectifier assembly and more particularly to a flow rectifier assembly including one or more valves.
Machines with two frame portions connected through a hitch assembly such as, for example, a wheel tractor-scraper, a tractor attached by hitch to a planter or other implement, and articulated trucks, are employed in various industries, such as agriculture, construction and mining. The wheel tractor scraper is often used to load, haul, eject and spread layers of earth, and typically includes a tractor portion coupled to a scraper portion by an articulated joint. The scraper portion has a rear frame section that supports a bowl for collecting and hauling material. During such operations, the scraper may transmit mechanical shocks to the tractor portion, including the operator station. These transmitted shocks may cause the operator discomfort.
Wheel tractor scrapers and other hitched or articulated machines may include a suspension system to dampen the transmission of shocks from the one portion of the machine to another portion of the machine through the hitch or articulation joint. Conventionally, the dampening portion of the suspension system includes a fixed orifice. Modern electronics now enable the use of variable orifices to improve the dampening characteristics of the suspension system. These valves may be used in conjunction with other valves which may be installed into a manifold. However, sometimes it may be difficult to install the manifold may in the suspension system because of the space constraints in the machine. Some manifolds may also constrict the flow in the suspension system.
U.S. Pat. No. 7,726,335 discloses a fuel system with a check valve work implement. The check valve work implement includes a valve body, a poppet valve having a valve stem and a valve head adjacent one end of the valve stem. The valve head have a truncated conical portion and a shoulder at the downstream end of the conical portion and integral with the valve head and the entire valve head have the conical portion.
In one aspect, the present disclosure provides a flow rectifier assembly including a manifold with a variable orifice disposed therein. Further, the flow rectifier assembly includes one or more valves disposed in the manifold and fluidly connected to the variable orifice to provide a uni-directional flow over the variable orifice. Each of the one or more valves includes a poppet. A fly-cut recess defined in the manifold includes a seat for resting the poppet.
In another aspect, the present disclosure provides a hydraulic suspension system including a hydraulic cylinder assembly. The hydraulic cylinder assembly includes a cylinder and a rod to define a head chamber and rod chamber. The head chamber is fluidly connected to the flow rectifier assembly. Further, one or more accumulators are adapted to selectively receive the pressurized hydraulic fluid from the hydraulic cylinder assembly via the flow rectifier assembly. The flow rectifier assembly including a manifold with a variable orifice disposed therein. Further, the flow rectifier assembly includes one or more valves disposed in the manifold and fluidly connected to the variable orifice to provide a uni-directional flow over the variable orifice. Each of the one or more valves includes a poppet. A fly-cut recess defined in the manifold includes a seat for resting the poppet.
In yet another aspect, the present disclosure provides a hitch assembly for a machine. The hitch assembly is configured to connect a first portion and a second portion of the machine. The hitch assembly includes an articulation hitch to pivotally couple the first portion and the second portion such that the hydraulic suspension system is dampingly connected to the first portion and the second portion. The hydraulic suspension system including a hydraulic cylinder assembly. The hydraulic cylinder assembly includes a cylinder and a rod to define a head chamber and rod chamber. The head chamber is fluidly connected to the flow rectifier assembly. Further, one or more accumulators are adapted to selectively receive the pressurized hydraulic fluid from the hydraulic cylinder assembly via the flow rectifier assembly. The flow rectifier assembly including a manifold with a variable orifice disposed therein. Further, the flow rectifier assembly includes one or more valves disposed in the manifold and fluidly connected to the variable orifice to provide a uni-directional flow over the variable orifice. Each of the one or more valves includes a poppet. A fly-cut recess defined in the manifold includes a seat for resting the poppet.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
The present disclosure related to a flow rectifier assembly in a hydraulic suspension system. The flow rectifier assembly having a variable orifice disposed in a manifold.
The present disclosure will now be described in detail with reference being made to accompanying drawings.
The front frame section 106 supports a power source 116 and a cooling system (not shown). The power source 116 is operatively connected through a transmission (not shown) to drive front wheels 118 located on opposite sides of the machine 100. The front frame section 106 may also support an operator station 120 for primary control of the machine 100 during operation. The rear frame section 110 supports a bowl 122 on rear wheels 124. The bowl 122 may also include a work implement 126, such as a conveyor 128. In other embodiments, the bowl 122 may include an auger, an elevator, and/or a spade, to facilitate penetration, loading, and/or unloading of material to be transported by the machine 100.
The power source 116 may be an internal combustion engine like a gasoline, diesel or natural gas engine, etc. The power source 116 may alternatively include a non-combustion source of power such as a fuel cell, a power storage device like a battery, an overhead conductor, or other similar devices. In an alternative embodiment, the machine 100 may include a hydraulic drive or an electric drive. For example, the power source 116 may be operatively connected to a pump, such as a variable or fixed displacement hydraulic pump to produce a pressurized fluid directed to one or more hydraulic motors associated with the front wheels 118. Alternatively, the power source 116 may be drivably connected to an alternator or generator configured to produce an electrical current used to power one or more electric motors for driving the front wheels 118 and/or the rear wheels 124. In addition to driving the front wheels 118, the power source 116 may be configured to supply power to the work implement 126 to penetrate and/or transfer material into or out of the bowl 122, or to perform other operations.
The hydraulic suspension system 200 may be a closed-loop hydraulic system including a hydraulic cylinder assembly 202, having an extendable rod 204, and disposed between and coupled to the first pivotable link 130. A body portion 206 of the hydraulic cylinder assembly 202 coupled with the second pivotable link 132. For example, the body 206 and the rod 204 attached to a tractor portion pivot 138 and a scraper portion pivot 140, respectively. However, it should be understood that the orientation of hydraulic cylinder assembly 202 may be inverted and/or switched as long as the first and the second pivotable links 130, 132 are configured to pivot between the tractor portion 104 and the scraper portion 108.
The body 206 of the hydraulic cylinder assembly may define a rod chamber 208 and a head chamber 210 provided with respective hydraulic lines 212, 214 to selectively receive a pressurized hydraulic fluid and cause retraction or extension of the rod 204. The extension and retraction of the rod 204 adjusts a relative height of the tractor portion 104 in relation to the scraper portion 108 on an uneven ground due to the pivoting of the first and second pivotable links 130, 132. The flow of the pressurized hydraulic fluid may be controlled by a leveling valve 216. The leveling valve 216 is configured to selectively receive the pressurized fluid from a fluid pump 218 that is powered by power source 116 or by some other power source and return the fluid to a holding tank 220 during the extension and retraction of the rod 204. The leveling valve 216 may also lock the rod 204 into a fully retracted position, a fully extended position, and/or at any position in between during operation of the machine 100.
Further, one or more accumulators 222 are fluidly coupled with the leveling valve 216 via an accumulator hydraulic line 224. The accumulator 222 may be a fluid tank having a free-floating piston, bladder, or other device that divides the accumulator 222 into different chambers. One chamber is for the pressurized fluid and one chamber is for a compressible gas (e.g., nitrogen). The accumulator 222 receives the pressurized fluid in a fluid chamber, which displaces the piston or bladder, thus compressing the gas in the gas chamber. Accordingly, the accumulator 222 provides compliance to the pressurized fluid.
According to an embodiment of the present disclosure, as will be explained in more detail below, the head chamber 210 is fluidly connected with a flow rectifier assembly 300 to influence a speed at of the rod 204 during the extension and retraction.
Further, in an embodiment, the flow rectifier assembly 300 may include two or more variable orifices 304 arranged in parallel to control the flow of the hydraulic fluid. The variable orifice 304 may be mechanically, hydraulically or electrically controlled by means of a controller (not shown). The controller may be pre-programmed to control the restriction of the variable orifice 304 by any means known in the art. These means may include mechanical, hydraulic, or electrical means. Further, the valves 302 of the may be check valves allowing the flow of the hydraulic fluid in one direction to guarantee the uni-directional flow of the hydraulic fluid through the variable orifice 304 during the flow of the hydraulic fluid from the accumulators 222 to the hydraulic cylinder assembly 202 and vice-versa.
In an embodiment, the manifold 310 may include intake ports 312 provided on opposite faces 314 (only one is shown) to connect with the hydraulic line 214 disposed between the head chamber 210 of the hydraulic cylinder assembly 202 and the leveling valve 216. Further, one or more shock valve ports 316 may be provided on a top face 318 of the manifold 310 wherein shock valves 320 having the variable orifice 304 may be secured using mechanical fasteners 322. In the illustrated embodiment, one of the shock valve ports 316 is closed using a port plug 324 and may be utilized to connect another shock valves 320 based on the requirement of the hydraulic system 200. Furthermore, valve ports 326 may be provided to accommodate the valves 302 on lateral faces 328 and a bottom face 330 of the manifold 310.
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The industrial applicability of a flow rectifier manifold with a fly-cut recess will be readily appreciated from the foregoing discussion. The flow rectifier manifold may be utilized in any off-highway machine with two frame portions connected through a hitch assembly such as, for example, a wheel tractor-scraper, a tractor attached by hitch to a planter or other implement, and articulated trucks, which are employed in various industries, such as agriculture, construction, earth moving operations like loading, hauling, and moving of material from one location to another location.
The machine 100 may be employed in push-pull operations, wherein the scraper portion 108 is either pulled or pushed by a second machine, for example, a track-type dozer or another wheel tractor-scraper, during the loading process. The machine 100 is often provided with push bars (not illustrated) to facilitate such operation. Some machines (e.g., twin-engine scrapers) may also be provided with an additional, rear mounted engine or other secondary propulsion power source system operatively connected to drive the scraper portion 108, making these machines better suited for handling adverse terrain and worksite conditions. Other alternatives provide a fluid operated drive assist system for the scraper portion 108 in the machine 100.
During operation of the machine 100, the work implement 126 is typically lowered to engage with the ground along a cutting edge that is driven forward by the machine 100, thus, scraping the earth and loading the bowl 122. The earth-moving work implement 126, such as the blade, elevator, conveyor, auger, or spade, associated with the bowl 122 facilitates penetration, loading, and/or unloading of the material to be transported.
During this process, some vibrations or shocks may be produced from the ground and the work implement 126 in the scraper portion 108. These shocks may be transferred from the scraper portion 108 to the tractor portion 104 in the machine 100. This may cause uncomfort to the operator in the operator station 120 disposed in the front frame section 106.
The articulation hitch 112 of the present disclosure may be configured as a cushion hitch to reduce the shock transfer from the scraper portion 108 and the ground to the tractor portion 104. The articulation hitch 112 may provide pivoting between the scraper portion 108 and the tractor portion 104 via the pivotable links 130, 132 to pivot and dampen-off the shocks. Thus, the articulation hitch 112 greatly reduces shock and vibration being transferred to an operator in the operator station 120 of the machine 100.
The hydraulic suspension system 200 may absorb the shocks through the hydraulic cylinder assembly 202 coupled between the tractor portion 104 and the scraper portion 108. The hydraulic suspension system 200 permits the rod 204 to retract and provide a flow of the hydraulic fluid from the hydraulic cylinder assembly 202 to the accumulator 222 via the flow rectifier assembly 300. The accumulator 222 may absorb and store energy as hydraulic energy due to the shocks. In the flow rectifier assembly 300, the hydraulic fluid may pass over the variable orifice 304 which may be regulated via a controller to create restriction in the flow of the hydraulic fluid to cause a controlled pressure drop and thus to reduce a bounce back in the hydraulic cylinder assembly 202 due to the flow of the hydraulic fluid. The valves 302 in the flow rectifier assembly 300 may selectively allow the hydraulic fluid to pass through by opening and closing.
For better regulation of the flow of the hydraulic fluid in the hydraulic circuit associated with hydraulic suspension system 200, the fly-cut recess 340 of the present disclosure may be provided in the manifold 310 for the seat 336 of the valve 302. The fly-cut recess 340 may allow and increase area for the flow with lesser restrictions to lower pressure drop about the valves 302 in the flow rectifier assembly 300. Further, lowering the unwanted pressure drop about the valves 302 may save some pressure energy of the hydraulic fluid in the hydraulic circuit and thus result in more efficient hydraulic suspension system 200 in the articulation hitch 112.
In addition to this, the fly-cut recess 340 defined in the seat 336 may allow for a shorter stroke length for the stem portion 332 of the valve 302 in the manifold 310. This allows for a more compact shape for the manifold 310 in the flow rectifier assembly 300. Further, this may provide possibilities for the manifold 310 of the present disclosure to be used in machines with space constraints for the flow rectifier assembly 300 to be utilized in the hydraulic suspension system 200.
Although the embodiments of this disclosure as described herein may be incorporated without departing from the scope of the following claims, it will be apparent to those skilled in the art that various modifications and variations can be made. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
