MOLDBOARD CONTROL DURING LOWERING OF MILLING DRUMS

Description

TECHNICAL FIELD

The present disclosure relates to milling machines having an enclosure assembly to enclose a milling drum. More particularly, the present disclosure relates to raising of a member of the enclosure assembly with a velocity equivalent to that of a lowering of the milling drum.

BACKGROUND

Milling machines, such as cold planers, generally include a milling assembly suspended below a frame of the machine. The milling assembly typically includes a milling enclosure and a milling drum. The milling enclosure surrounds the milling drum, while the milling drum is rotated and applied for milling an underlying surface. The milling enclosure may include various components, including side gates and a rear gate (commonly referred to as a moldboard and/or a scraper door). The moldboard may be adjustable via actuators, such as fluid actuators, and may be provided to confine and limit the spread of the milled materials within the milling enclosure and to also direct materials milled by the milling drum on to a conveyor.

During a milling operation, the milling drum of the milling assembly may be lowered (e.g., with the milling drum rotating) towards and/or into the underlying surface for milling said underlying surface. A lowering of the milling drum is commonly referred to as a plunging operation. In such situations, one or more components or members of the milling enclosure (e.g., the moldboard) may prevent the milling drum from reaching a target depth, e.g., if the moldboard were to interfere with any part of the enclosure assembly and/or with the underlying surface.

U.S. Patent No.: 10,612,196 relates to a milling machine which includes a frame, a ground engaging rotor assembly, a moldboard, and a hydraulic cylinder including a piston rod and a piston barrel. The ground engaging rotor assembly is at least partially enclosed by the moldboard. The moldboard is vertically movable via the hydraulic cylinder, and the hydraulic cylinder is coupled to the frame via a dual-trunnion assembly.

SUMMARY

In one aspect, the present disclosure discloses a milling machine. The milling machine includes a milling drum, an enclosure assembly, an actuator, and a controller. The milling drum is configured to be lowered into a surface to modify the surface. The enclosure assembly defines a volume to enclose the milling drum. Also, the enclosure assembly includes a member configured to be raised and lowered with respect to the surface. The actuator moves the member selectively between a lowered position and a raised position with respect to the surface. The controller is configured to determine a first velocity of the milling drum during a lowering of the milling drum into the surface. Further, the controller is also configured to issue an instruction to actuate the actuator such that the member is raised towards the raised position with a second velocity with respect to the surface during the lowering of the milling drum into the surface. A magnitude of the first velocity is equal to a magnitude of the second velocity.

In another aspect, the disclosure relates to a method for lowering a milling drum of a milling machine into a surface for performing a milling operation on the surface. The milling drum is enclosed by an enclosure assembly. The method includes determining, by a controller, a first velocity of the milling drum during the lowering of the milling drum into the surface. Further, the method includes issuing, by the controller, an instruction to actuate an actuator such that a member associated with the enclosure assembly is raised towards a raised position with a second velocity with respect to the surface during the lowering of the milling drum into the surface. A magnitude of the first velocity is equal to a magnitude of the second velocity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a milling machine having a milling system with an enclosure assembly having a milling drum, in accordance with an embodiment of the present disclosure;

FIG. 2 is a rear view of a member of the enclosure assembly configured to be raised and lowered with respect to a surface underlying the milling machine, in accordance with an embodiment of the present disclosure;

FIG. 3 is an exemplary hydraulic system illustrating valves according to a first embodiment that facilitates a raising of the member during a lowering of the milling drum;

FIG. 4 is another exemplary hydraulic system illustrating valves according to a second embodiment that facilitates a raising of the member during a lowering of the milling drum; and

FIG. 5 is a flowchart illustrating an exemplary method for lowering the milling drum into the underlying surface for performing a milling operation on the surface, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to specific embodiments or features, examples of which are illustrated in the accompanying drawings. Generally, corresponding reference numbers may be used throughout the drawings to refer to the same or corresponding parts, e.g., 1, 1`, 1``, 101 and 201, could refer to one or more comparable components used in the same or different depicted embodiments.

Referring to FIG. 1, a machine 100 is described. The machine 100 may include a milling machine 104, such as a roadway/pavement profiler, a roadway planer, a cold planer, and the like machines. The machine 100 may be used for performing operations to modify a surface 108. Modifying the surface 108 may mean one or more of milling, scarifying, removing, mixing, or reclaiming material from the surface 108. The surface 108 may underlie the machine 100 during operations, and, accordingly, may also be referred to as an underlying surface. As an example, the surface 108 may be a worn-out surface of a roadway, which may be formed from one or more of asphalt, bitumen, concrete, and/or other road surface materials, and said surface 108 may be milled to be removed for the laying of a new surface.

The machine 100 may include a machine frame 112, a milling system 116 supported on the machine frame 112, a conveyor 120, and traction devices 124 to support and propel the machine 100 over the surface 108. During milling operations, the surface 108 of the roadway may be milled by the milling system 116 as the machine 100 moves over the surface 108 (e.g., see direction, T). The milling operation may facilitate disintegration of the surface 108 of the roadway to form milled materials. Said milled materials may be transferred to the conveyor 120 and the conveyor 120 may in turn transfer the milled materials into a dump body of a transport vehicle (e.g., a dump truck) (not shown) that may move ahead of the machine, e.g., along direction, T.

The traction devices 124 may enable the machine 100 to move over the surface 108 such that a modified surface may be formed as the machine 100 progresses or moves along direction, T. The traction devices 124 may include endless tracks and/or wheels and/or a combination thereof. Exemplarily, the machine 100 may include four traction devices (e.g., one at each corner of the machine frame 112), although lesser or higher number of traction devices may be applied in some cases. The traction devices 124 may be adjustably supported to the machine frame 112, such that a distance (e.g., a height) of the machine frame 112 may be varied relative to the traction devices 124 (or to traction frames associated with the traction devices) (e.g., see traction frame 128) and thus to the surface 108 underlying the machine 100. In this regard, it may be noted that each of the traction devices 124 may be adjusted and varied independently of the other with respect to the machine frame 112. In so doing, it is possible for the machine frame 112 to stand or be stationed over uneven contours of the surface 108, but still acquire a desired orientation (e.g., a horizontal orientation) by having the traction devices 124 suitably adjusted and independently varied with respect to the machine frame 112.

Adjustment and variation of the traction devices 124 may be facilitated through traction actuators – only one traction actuator, i.e., traction actuator 132, is annotated in FIG. 1 and discussed. Discussions associated with the traction actuator 132 may be contemplated and suitably applied for all the traction actuators associated correspondingly with the traction devices 124 of the machine 100. The traction actuator 132 may be a hydraulic actuator. Said traction actuator 132 may include a cylinder-rod based arrangement. A rod of such an arrangement may selectively extend and retract relative to a cylinder of such an arrangement. Notably, an extension of the rod may cause the machine frame 112 to be raised relative to the traction devices 124 (and the surface 108), while a retraction of the rod may cause the machine frame 112 to be lowered relative to the traction devices 124 (and the surface 108). Fluid may be supplied and circulated with respect to the traction actuator 132 to power the traction actuator 132 through a suitable hydraulic circuit.

The milling system 116 may be configured to facilitate the milling operation of the machine 100. The milling system 116 may include a milling drum 140, which may be utilized to modify the surface 108. To this end, the milling drum 140 may include a drum portion and multiple cutter tools arranged over and around the drum portion (not shown). The milling drum 140 may be powered (e.g., by a belt drive mechanism and/or may be run by at least one of electrically and/or hydraulically) to rotate and be lowered to contact the surface 108. In so doing, the milling drum 140 may grind and scrape off a top of the surface 108 over which the machine 100 is moved, thus modifying the surface 108. During such operation (e.g., a milling operation), the top of the surface 108 of the roadway may disintegrate into rubble, dust, and debris, forming disintegrated particles or milled materials. A lowering of the milling drum 140 (when still rotating) into the surface 108 of the roadway is commonly referred to as a plunge operation associated with the machine 100 and the associated functionality achieved is commonly referred to as a plunge-cut.

Although aspects in the present disclosure have been discussed in relation to the milling drum 140 and its lowering into the surface 108 during a milling operation, aspects of the present disclosure may be suitably applied to various other implements and/or machines having implements that not necessarily include a milling drum. For example, aspects of the present disclosure may be applied to machines in which an implement of the machine 100 may be engaged with (and/or inserted into) a ground surface and a panel associated with such an implement need to be cleared away from interfering with the ground surface to allow the implement to plunge properly into the ground surface.

In some instances, a lowering of the milling drum 140 may be facilitated by adjusting one or more of the traction devices 124 with respect to the machine frame 112. For example, reducing the distance between the traction devices 124 and the machine frame 112 may cause the milling drum 140 to be lowered relative to (e.g., into/towards) the surface 108. Such lowering of the milling drum 140 may be attained by the retraction of the rod of the traction actuator 132 relative to or into the cylinder of the traction actuator 132. Also, such lowering of the milling drum 140 may be initiated by a command (e.g., a lowering command) issued by a grade control system of the machine 100 and/or by one or more operators of the machine 100. In one embodiments, such commands may be issued by said operators through an input device and/or an operator interface 136 (see FIGS. 3 and 4) that may be provided within an operator station 144 of the machine 100.

Conversely, a raising of the milling drum 140 may be initiated by another command (e.g., a raising command) issued by the grade control system of the machine 100 and/or by the operators (e.g., by using the input device and/or operator interface 136 provided within the operator station). Raising of the milling drum 140 relative to the traction devices 124 and the surface 108 underlying the machine 100 may be attained by the extension of the rod of the traction actuator 132 relative to or away from the cylinder of the traction actuator 132. In effect, the traction devices 124 may be moveable with respect to the machine frame 112 during the lowering or during the plunge-cut of the milling drum 140 into the surface 108, and, also, may be moveable during the raising of the milling drum 140 away from the surface 108.

In some embodiments, the machine 100 and/or the milling system 116 may include a traction device sensor 148 (see FIGS. 3 and 4) to detect the distance between the machine frame 112 and one or more of the traction devices 124 (e.g., traction device 124`). To this end, the traction device sensor 148 may be coupled to a portion of the machine frame 112, e.g., relatively close to the traction device 124` such that the traction device sensor 148 may gauge the distance between the machine frame 112 and the traction frame 128. Further, the traction device sensor 148 may correspondingly generate signals indicating the proximity of the machine frame 112 relative to the traction frame 128. To this end, the traction device sensor 148 may include one or more of a proximity sensor and/or an ultrasonic sensor. Other sensor types may be contemplated.

In some embodiments, the traction device sensor 148 may be coupled and/or positioned elsewhere, e.g., on the traction actuator 132, such as on one of the rod and the cylinder of the traction actuator 132 and which may be configured to detect a position of the other of the rod and the cylinder of the traction actuator 132. In some embodiments, sensors similar to the traction device sensor 148 may be provided corresponding to all traction devices 124 of the machine 100. A variety of other sensor positions may be contemplated for the traction device sensor 148 by those skilled in the art, and it may be noted that the position and/or type of the traction device sensor 148, as discussed in the present disclosure, is purely exemplary. Moreover, other methods and systems to detect the distance between the machine frame 112 and the traction devices 124 may contemplated, and it will be appreciated that using sensors, such as the traction device sensor 148, is simply one among the many methods of detecting the distance between the machine frame 112 and one or more of the traction devices 124.

Referring to FIGS. 1 and 2, the milling system 116 may also include an enclosure assembly 152. The enclosure assembly 152 may be supported on and/or be suspended under the machine frame 112 and may be adapted to enclose the milling drum 140 such that the disintegrated particles or the milled materials produced during the milling operation may be restrained and confined within a chamber or a volume 156 defined by the enclosure assembly 152 around the milling drum 140 to enclose the milling drum 140. The enclosure assembly 152 may define a roof or an elevated portion 168 (see FIG. 2) that may be coupled and supported to the machine frame 112 (e.g., to an underside of the machine frame 112). Further, the enclosure assembly 152 may include a number of components or members 160, for example, a scraper door (or a moldboard 164) and side gates 172 (see FIGS. 1 and 2). The enclosure assembly 152 may also include an anti-slab device (not shown), which may be positioned opposite to the moldboard 164.

The members 160, e.g., the moldboard 164, the side gates 172, and the anti-slab device, may be independently configured to be pushed out or be pulled up relative to the elevated portion 168 or the machine frame 112 to be raised and lowered with respect to the surface 108 – see lowering direction, LD, and a rising direction, RD, in FIG. 2. In so doing, each of the members 160 may be independently moved between a closed state and an open state with respect to the elevated portion 168 or the machine frame 112. For example, when one of the members 160, e.g., the moldboard 164, is pushed out with respect to the machine frame 112, the moldboard 164 may move to the closed state, while when the moldboard 164 is pulled up with respect to the machine frame 112, the moldboard 164 may move to the open state. In the open state of the moldboard 164, access may be gained (at least partially) to the volume 156 and to the milling drum 140 from an outside, while in the closed state of the moldboard 164, access may be blocked or closed (at least partially) to the volume 156 and to the milling drum 140 from the outside. Similar discussions may be contemplated for the members 160 other than the moldboard 164, as well. A configuration of the moldboard 164 illustrated in FIG. 2 may relate to a closed state of the moldboard 164.

In the closed state of all the members 160 (e.g., when the members 160 may be pushed out), the members 160 may together surround and enclose the milling drum 140 from all sides to define (e.g., fully define) the volume 156. In said closed state of the members 160, the members 160, enclosing the milling drum 140, may contain the disintegrated particles or the milled materials within the enclosure assembly 152, and so that the disintegrated particles or the milled materials, as milled by the milling drum 140, may be retained within the enclosure assembly 152 and inevitably be guided and directed to the conveyor 120. As an example, when the moldboard 164 is lowered (e.g., direction, LD), the moldboard 164 may close the enclosure assembly 152 and shield the volume 156 from an outside of the enclosure assembly 152, and when the moldboard 164 is raised, the moldboard 164 may open the enclosure assembly 152 and reveal the volume 156 and the milling drum 140 to the outside of the enclosure assembly 152.

Various aspects of the present disclosure are discussed with respect to the moldboard 164. Such discussions may be suitably applied to the remainder of the members 160 (i.e., the opposing side gates and the anti-slab device) as well. With regard to the moldboard 164, the milling system 116 may include a pair of actuators 176 (e.g., a first actuator 176` and a second actuator 176``) that may be actuated (e.g., synchronously) between a first state and a second state to correspondingly move the moldboard 164 between the closed state and the open state. A higher or a lower number of actuators 176 may be contemplated to move the moldboard 164 between the closed state and the open state. The forthcoming discussion may mainly include references to the first actuator 176` alone, and such discussions may be applicable to the second actuator 176``, as well. For ease, the first actuator 176` may be simply referred to as an actuator 176.

The actuator 176 may be a fluid actuator (e.g., a hydraulic actuator 180) that may be part of a hydraulic system 184 of the milling system 116 of the machine 100. The hydraulic system 184 may be configured to perform several operations, e.g., moving the moldboard 164 between the closed state and the open state. According to an aspect of the present disclosure, the hydraulic system 184 is applied to raise the moldboard 164 upwards and away from the surface 108, as the milling drum 140 may be lowered (see direction, LD, FIG. 2) towards and/or into the surface 108 during the plunge-cut. Such raising of the moldboard 164 prevents the moldboard 164 from binding and/or impinging against the surface 108 and/or any other machine part of the machine 100 as the milling drum 140 may be lowered towards the surface 108 during the plunge-cut. Moreover, such moldboard control does not prevent the milling drum 140 from plunging to its target cut depth, or, in other words, ensures that a travel of the milling drum 140 to the target depth is attained without any interference of the moldboard 164 with the surface 108 and/or with any other machine part.

Referring to FIGS. 3 and 4, and with continued reference to the actuator 176, the actuator 176 may include a cylinder-rod arrangement, and thus may include a cylinder 188 and a rod 192 extendable and retractable with respect to the cylinder. The rod 192 may include a piston 196 that may divide the cylinder 188 into a head end chamber 200 and a rod end chamber 204. When fluid is pumped into the head end chamber 200 of the actuator 176 (i.e., when the head end chamber 200 receives fluid pressure), the actuator 176 may be actuated such that the piston 196 may be pressurized to push and force the rod 192 to extend out of the cylinder 188 to move the actuator 176 to an extended position. When fluid is pumped into the rod end chamber 204 of the actuator 176 (i.e., when the rod end chamber 204 receives fluid pressure), the actuator 176 may be actuated such that the piston 196 may be pressurized to push and force the rod 192 to retract into the cylinder 188 to move the actuator 176 to a retracted position.

It may be noted that when the actuator 176 is moved to the extended position, the moldboard 164 is pushed out and is lowered with respect to the surface 108 to a lowered position, while when the actuator 176 is moved to the retracted position, the moldboard 164 is pulled up and is raised with respect to the surface 108 to a raised position. Because a state of the moldboard 164 illustrated in FIGS. 1 and 2 may correspond to the closed state, the position of the actuator 176 in said closed state may correspond to the extended position.

With regard to an assembly of the actuator 176 to the moldboard 164, to achieve the aforesaid operational relationship between the actuator 176 and the moldboard 164, the cylinder 188 may be coupled to the roof and/or to the elevated portion 168 of the enclosure assembly 152 (see FIG. 2), while the rod 192 may be coupled to the moldboard 164. In so doing, an extension of the rod 192 relative to the cylinder 188 (i.e., moving the actuator 176 to the extended position) may cause the moldboard 164 to be pushed out and be moved to the closed state, while a retraction of the rod 192 relative to the cylinder 188 (i.e., moving the actuator 176 to the retracted position) may cause the moldboard 164 to be pulled up and be moved to the open state. Effectively, the head end chamber 200 may receive fluid pressure to actuate the actuator 176 towards the extended position and move the moldboard 164 towards the closed state, and the rod end chamber 204 may receive fluid pressure to actuate the actuator 176 towards the retracted position and move the moldboard 164 towards the open state.

Although the above discussion, in an alternate scenario, it is possible that when the actuator 176 may move to the retracted position, the moldboard 164 may be moved to the closed state, and, conversely, when the actuator 176 may move to the extended position, the moldboard 164 may be moved to the open state. In such cases, an assembly between the actuator 176 and the moldboard 164 may vary and differ from what has been discussed above. Such an assembly may be contemplated by those of skill in the art and will not be discussed.

In one embodiment, the actuator 176 may include an actuation sensor 208. The actuation sensor 208 may generate signals indicating the proximity of the rod 192 relative to the cylinder 188. In other words, the actuation sensor 208 may facilitate detection of a position of the rod 192 relative to the cylinder 188. As with the traction device sensor 148, the actuation sensor 208 may also include one or more of a proximity sensor or an ultrasonic sensor, although other sensor types may be contemplated. The actuation sensor 208 may be coupled to a portion of the cylinder 188. In some embodiments, the actuation sensor 208 may be positioned elsewhere on the actuator 176. Alternatively, the actuation sensor 208 may be positioned on the rod 192 (e.g., on the piston 196 of the rod 192) to facilitate detection of the position of the cylinder 188 relative to the rod 192, enabling determination of a distance therebetween. As another example, the actuation sensor 208 may be positioned outside the actuator 176. A variety of such positions of the actuation sensor 208 may be contemplated by those skilled in the art, and it may be noted that the position, location, and/or type of the actuation sensor 208, as discussed in the present disclosure, is purely exemplary. Moreover, other methods and/or systems to detect the position of the rod relative to the cylinder may be contemplated, and it will be appreciated that a method of detecting the position of the rod 192 relative to the cylinder 188 by use of the actuation sensor 208 is simply one among the many methods of detecting the position of the rod 192 relative to the cylinder 188.

In some embodiments, the members 160 other than the moldboard 164 (e.g., one or more of the side gates 172) of the enclosure assembly 152 may also include actuators, e.g., see actuator 260 in FIGS. 1 and 2. The actuator 260 may be similar (e.g., in structure and arrangement) to the actuator 176 and may include a sensor (not shown) which may be similar to the actuation sensor 208. Such actuators may be used to selectively raise and lower said members 160 with respect to the surface 108. As with the actuation sensor 208, the sensor associated with the actuator 260 may facilitate a detection of a position of the rod of the actuator 260 relative to the cylinder of the actuator 260.

Referring to FIG. 3, the hydraulic system 184 may include a fluid reservoir, R, a fluid source, S, a set of valves (e.g., a first valve 212 and a second valve 216), and a set of fluid lines fluidly interconnected between each of the actuator 176, the fluid reservoir, R, the fluid source, S, and the set of valves (i.e., the first valve 212 and second valve 216) to form a hydraulic circuit 218 of the hydraulic system 184. The hydraulic system 184 may also include a controller 220 that may be applied to control the valves (i.e., the first valve 212 and the second valve 216), and such that variations in fluid pressure and supply may be suitably delivered to the actuator 176, e.g., the rod end chamber 204 of the actuator 176. Details and application related to the controller 220 will be discussed later in the present disclosure.

The fluid source, S, may include a fluid pump that pumps and facilitates a supply of fluid pressure to the actuator 176, e.g., to the head end chamber 200 and the rod end chamber 204 of the actuator 176, to selectively actuate the actuator 176 to the extended position and to the retracted position. A first fluid line 224 may fluidly extend from the fluid source, S, to the first valve 212; a second fluid line 228 may fluidly extend from the first valve 212 to the second valve 216; a third fluid line 232 may fluidly extend from the second valve 216 to the head end chamber 200 of the actuator 176; a fourth fluid line 236 may fluidly extend from the rod end chamber 204 of the actuator 176 to the second valve 216; a fifth fluid line 240 may fluidly extend from the second valve 216 to the fluid reservoir, R; and a sixth fluid line 244 may fluidly extend between the first valve 212 and the fifth fluid line 240, as shown.

The first valve 212 may be fluidly coupled between the fluid source, S, and the second valve 216. Although not limited, the first valve 212 may be a two-way, two-position valve to be varied or moved between two positions (or two locations, namely a first location and a second location). For example, in the first location of the first valve 212 (which is also the location as shown in FIG. 3), the first valve 212 may facilitate a coupling (e.g., fluid coupling) of the first fluid line 224 with the second fluid line 228. For example, in the second location, the first valve 212 may facilitate a coupling (e.g., fluid coupling) of the second fluid line 228 with the sixth fluid line 244. Moreover, in the first location of the first valve 212, the first valve 212 may facilitate fluid coupling of the fluid source, S, to the second valve 216 to facilitate supply of fluid from the fluid source, S, to the second valve 216. In the second location of the first valve 212, the first valve 212 may facilitate fluid coupling of the second valve 216 to the fluid reservoir, R, to facilitate drainage of fluid from the second valve 216 to the fluid reservoir, R.

The first valve 212 may include a proportional pressure control valve 212` that, for example, may be applied to regulate and set fluid pressure at a set value (or a predefined value). For example, the first valve 212, in the first location, may regulate fluid pressure delivered into the second fluid line 228 independent of an input pressure or a fluid pressure received through the first fluid line 224. This may be possible by way of varying a solenoid current that may be supplied to a solenoid associated with the first valve 212. In other words, the first valve 212 may supply fluid pressure at the set value (and/or the predefined value) according to a magnitude of power (e.g., current) received by the solenoid. In that manner, the fluid pressure may be delivered into the second fluid line 228 at the set value irrespective of the fluid pressure received as input through the first fluid line 224. By way of the proportional control, the first valve 212, in the first location, may be regulated to supply fluid pressure into the head end chamber 200 and the rod end chamber 204. An exemplary manner by which fluid is regulated is discussed later in the present disclosure.

The second valve 216 may be fluidly coupled between the actuator 176 and the first valve 212. Although not limited, the second valve 216 may be a three-way, three-position valve to be varied or moved between three positions (or three locations, namely a third location, a fourth location, and an intermediate location which may be defined in between the third location and the fourth location). The location of the second valve 216 shown in FIG. 3 is exemplarily the intermediate location. From FIGS. 3 and 4, the third location may be understood as a location of the second valve 216 when the second valve 216 moves relatively leftwards relative to the intermediate location. Similarly, the fourth location may be understood as a location of the second valve 216 when the second valve 216 moves relatively rightwards relative to the intermediate location.

For example, with the first valve 212 in the first location and the second valve in the third location, the second valve 216 may facilitate routing of flow of fluid received from the first valve 212 to the rod end chamber 204 of the actuator 176. For example, with the first valve 212 in the first location and the second valve 216 in the fourth location, the second valve 216 may facilitate routing of flow of fluid received from the first valve 212 to the head end chamber 200 of the actuator 176. For example, in the intermediate location of the second valve 216, the second valve 216 may facilitate a float functionality of the actuator 176 and/or the moldboard 164, e.g., in which the head end chamber 200 and the rod end chamber 204 may be fluidly coupled to each other through a channel 248 defined by or through the second valve 216.

Referring to FIG. 4, a hydraulic system 184` is discussed. The hydraulic system 184` may be similar to the hydraulic system 184 and may have similar connections and layout as has been discussed for the hydraulic system 184, but with the exception that the hydraulic system 184` may include a different first valve (i.e., the first valve 212 applied in the hydraulic system 184` may be referred to as a third valve 252 for ease of reference) instead of ‘first valve’. The third valve 252 may include a proportional flow control valve 252`. The hydraulic system 184` may be applied in the machine 100 (or in the milling system 116 of the machine 100) either alternatively to the hydraulic system 184 or combinedly with the hydraulic system 184. For ease of reference, similar reference numerals are used in both FIGS. 3 and 4, wherever possible. Also, discussions further below may include references to the first valve 212. Those discussions may be suitably applied to the third valve 252, as well. Wherever needed, references to the third valve 252 shall also be used.

The controller 220 may be communicatively coupled to the first valve 212 and the second valve 216. In so doing, the controller 220 may be able to suitably actuate and/or regulate the first valve 212 and the second valve 216 in their respective locations. Further the controller 220 may also be communicatively coupled to the traction device sensor 148 and the actuation sensor 208 to receive signals from each of the traction device sensor 148 and the actuation sensor 208. Moreover, the controller 220 may also be communicatively coupled to the operator interface 136 provided within the operator station 144 of the machine 100 to receive the commands (e.g., the lowering command and/or the raising command) from the operator interface 136.

As an example, in response to the receipt of the lowering command, the controller 220 may be configured to extract a set of instructions from a memory 256. Based on the set of instructions, the controller 220 may be configured to run the set of instructions to determine a velocity (e.g., a first velocity) of the milling drum 140 during the lowering of the milling drum 140 into the surface 108. Further, the controller 220 may be configured to issue an instruction to actuate the actuator 176 such that the members 160 and/or the moldboard 164 is raised towards the raised position with a second velocity with respect to the surface 108 during the lowering of the milling drum 140 into the surface 108. A magnitude of the first velocity may be equal to a magnitude of the second velocity. In some embodiments, the term ‘equal’ may mean that the magnitude of the second velocity may be within a permissible range with respect to the magnitude of the first velocity. In some embodiments, the term ‘equal’ may mean that the magnitude of the second velocity may be within a permissible range within which the magnitude of the first velocity is defined. An exemplary manner in which the first velocity may be determined shall be discussed later in the present disclosure.

In addition to the above, the controller 220, based on the running of the set of instructions, may also be configured to shift or switch the first valve 212 and the second valve 216 between multiple positions, e.g., the first valve 212 between its two corresponding locations; and the second valve 216 between its three corresponding locations. Further, the controller 220 may also determine a current, e.g., a first current, corresponding to the first velocity. In some embodiments (e.g., in a first embodiment), the controller 220 may cause the first current to be supplied to the first valve 212 in the first location of the first valve 212 such that the first valve 212 is regulated to supply fluid pressure into the rod end chamber 204 based on which the second velocity of the member 160 (e.g., moldboard 164) is attained. In some embodiments (e.g., in a second embodiment), and in the case the hydraulic system 184` (FIG. 4) is used, the controller 220 may determine a second current corresponding to the first velocity and may cause the second current to be supplied to the first valve 212 (or third valve 252) in the first location of the first valve 212 (or third valve 252) such that the first valve 212 (or third valve 252) is regulated to supply fluid flow into the rod end chamber 204 based on which the second velocity of the member 160 (e.g., the moldboard 164) is attained.

The controller 220 may correspond to one or more controllers which may be communicably coupled to the machine’s main control module (not shown), such as a safety module or a dynamics module, or the controller 220 may be configured as a stand-alone entity. Optionally, the controller 220 may be integral to or be one and the same as the machine’s main control module. In some embodiments, one or more controlling portions of the controller 220 may be within the machine 100, while the other controlling portions may be situated outside the machine 100, e.g., remotely to the machine 100. In some embodiments, the controller 220 may be positioned entirely outside the machine 100, e.g., remotely from the machine 100.

Further, the controller 220 may include a microprocessor-based device, or the controller may be envisioned as an application-specific integrated circuit, or other logic devices, which provide controller functionality, and such devices or systems being known to those with ordinary skill in the art. In some embodiments, the set of instructions may be provided in any computer readable media, for example, any non-transitory computer readable media, and that when executed by the controller 220 may result in one or more of the functions of the controller 220, as has been described herein.

In one example, it is possible for the controller 220 to include or be representative of one or more controllers or control systems having separate or integrally configured processing units to process a variety of data, such as input or commands or signals incoming from the input device or the operator interface 136. In some embodiments, a transmission of data between the operator interface 136 and the controller 220 and/or between the controller 220 and various other systems or devices may be facilitated wirelessly or through a standardized CAN bus protocol. Although not limited, the controller 220 may be optimally suited for accommodation within certain panels or portions, such as machine panels or portions, from where the controller 220 may remain accessible for ease of use, service, calibration, repairs, and replacements.

Processing units or any one or more processors associated with the controller, to convert or process various input, command, signals, etc., may include, but are not limited to, an X86 processor, a Reduced Instruction Set Computing (RISC) processor, an Application Specific Integrated Circuit (ASIC) processor, a Complex Instruction Set Computing (CISC) processor, an Advanced RISC Machine (ARM) processor, or any other processor now known or in the future developed.

Examples of the memory 256 may include a hard disk drive (HDD), and a secure digital (SD) card. Further, the memory 256 may include non-volatile/volatile memory units such as a random-access memory (RAM) / a read only memory (ROM), which may include associated input and output buses. The memory 256 may be configured to store various other instruction sets for various other functions of the machine 100, along with the set of instruction, described above. Although not limited, the memory 256 may be configured within and may form part of the controller 220, in some cases.

INDUSTRIAL APPLICABILITY

During a milling operation, an operator of the machine 100 may power the milling drum 140 such that the milling drum 140 may rotate. Thereafter, the operator may lower the milling drum 140 relative to the surface 108 so that the milling drum 140 (when still rotating) may contact the surface 108 and break it open such that portions of the surface 108 may disintegrate into rubble, dust, and debris, in turn forming disintegrated particles or milled materials. Thereafter, as the machine 100 may execute motion over the surface 108 (e.g., see direction, T), the milling drum 140 may continue to be powered and rotated (i.e., operated), such that the surface 108 may be milled along an expanse of the roadway.

As and when a lowering of the milling drum 140 may be needed, the operator may feed a corresponding input into the operator interface 136. Based on the operator's input, a command (e.g., a lowering command) to lower the milling drum 140 may be generated and a controller (which may be one and the same as the controller 220) may cause the rod of the traction actuator 132 to retract into the cylinder of the traction actuator 132 in order to reduce the distance between the machine frame 112 and the traction frame 128, inevitably causing the milling drum 140 to be lowered relative to the surface 108 to contact the surface 108. It may be noted that at a start of lowering of the milling drum 140, all members 160 (e.g., the moldboard 164) of the enclosure assembly 152 may be in the closed state as said members 160 may define and establish the volume 156 and/or a closed boundary within which the disintegrated particles or milled materials need to be contained during the milling operation.

In such instances, where the milling drum 140 may be lowered (see direction, LD, FIG. 2), the possibility for one or more components or members 160 of the enclosure assembly 152 (e.g., the moldboard 164) to catch and/or bind on and/or against certain portions of the surface 108 or other members of the enclosure assembly 152 may be relatively high. This is because, during milling operations, the actuator 176 may be in the extended position and the moldboard 164 may be in the closed state. If the actuator 176 were to remain in the extended position and the moldboard 164 were to remain in the closed state, the moldboard 164 may interfere with any part of the enclosure assembly 152 and/or with the surface 108 and thus prevent the milling drum 140 from reaching a target depth.

To ensure that such interference and/or binding is averted, a method for lowering the milling drum 140 is described. The method is described in conjunction with a flowchart 500 illustrated in FIG. 5. More particularly, at block 502 of the flowchart 500, as the milling drum 140 may be lowered, the controller 220 may determine the first velocity, i.e., the velocity with which the milling drum 140 is lowered towards and/or into the surface 108. To determine the first velocity, the controller 220 may source data from the traction device sensor 148 and may detect a distance between the machine frame 112 and traction frame 128 (or the traction device 124`) at various instances during the lowering process of the milling drum 140. In process of doing so, the controller 220 may also determine a rate of change of distance between the machine frame 112 and traction frame 128 (or the traction device 124`) and based on which the controller 220 infer said rate of change as the first velocity. In some embodiments, the controller 220 may be configured to source data from a sensor positioned within one or more of the other actuators that may may move during the lowering process, e.g., see actuator 260 associated with another member (e.g., one or more of the side gates 172) of the enclosure assembly 152.

Further, at block 504 of the flowchart 500, and during the lowering of the milling drum 140 into the surface 108, the controller 220 may issue the instruction to actuate the actuator 176 such that any of the members (e.g., the moldboard 164) associated with the enclosure assembly 152 may be raised towards a raised position or pulled upwards (see direction, RD, FIG. 2) with a second velocity with respect to the surface 108. The second velocity may be equal to the first velocity. In some embodiments, the magnitude of the second velocity may be within a permissible range with respect to the magnitude of the first velocity or may be within a permissible range within which the magnitude of the first velocity is defined.

In some embodiments, the controller 220 (or alternatively another controller or a control system of the machine 100) may shift or switch the first valve 212 to the first location (e.g., from the second location) in response to the instruction. Also, in some embodiments, the controller 220 (or alternatively another controller or a control system of the machine 100) may shift or switch the second valve 216 to the third location (e.g., from the fourth location or the intermediate location) in response to the instruction. An exemplary manner in which the controller 220 may enable the member 160 (e.g., the moldboard 164) to achieve the second velocity will now be discussed.

In the case of the hydraulic system 184 having the first valve 212 (or the proportional pressure control valve 212`) is applied, in response to the determination of the first velocity by the controller 220, the controller 220 may retrieve a map (e.g., from the memory 256) that may include several first velocities tallied correspondingly against several first currents. Such correspondence between the first velocities and the first currents may be calibrated and stored in the memory 256 separately. From the map, the controller 220 may compare the first velocity with a corresponding first current and may associate and obtain a first current that may correspond to the determined first velocity (e.g., as inferred from the aforementioned rate of change of distance between the machine frame 112 and the traction device 124) from the map.

In the case of the hydraulic system 184` having the third valve 252 (or the proportional flow control valve 252`), in response to the determination of the first velocity by the controller 220, the controller 220 may retrieve a different map, but which may be similar to the one noted above, (e.g., from the memory 256) that may include several first velocities tallied correspondingly against several second currents. Such correspondence between the first velocities and the second currents may be calibrated and stored in the memory 256 separately. From said different map, the controller 220 may compare the first velocity with a corresponding second current and may associate and obtain a second current that may correspond to the determined first velocity (as inferred from the aforementioned rate of change of distance between the machine frame 112 and the traction device 124) from said different map. Although not limited, the first current and the second current may differ in magnitude and one or more other parameters (e.g., a time for which it may be applied) in actual practice and/or application. Such differences may be contemplated by those of skill in the art.

It may be noted that the first current may include a current value that when supplied to the first valve 212 may regulate the first valve 212 such that fluid released from the first valve 212 and flowing through the second valve 216 (e.g., via the first fluid line 224, second fluid line 228, and the fourth fluid line 236) may enter into the rod end chamber 204 to pressurize and move the actuator 176 to the retracted state with the second velocity. With the first valve 212 in the first location and the second valve 216 in the third location, fluid from the head end chamber 200 may drain out and find its way into the reservoir, R (e.g., via the third fluid line 232 and the fifth fluid line 240).

In the case of the hydraulic system 184 of FIG. 3, or in the first embodiment, that uses the first valve 212 as the proportional pressure control valve 212`, a delivery of the first current to the first valve 212 may regulate the first valve 212 such that the first valve 212 may supply fluid pressure (e.g., a commensurate fluid pressure) into the rod end chamber 204 based on which the second velocity of the member 160 (e.g., moldboard 164) may be attained. The delivery of the first current to the first valve 212 may also set a pressure (e.g., fluid pressure) of the first valve 212 independent of the fluid pressure that may be received by the first valve 212 from the fluid source, S. Conversely, in the case of the hydraulic system 184` of FIG. 4, or in the second embodiment, that uses the third valve 252 as the proportional flow control valve 252`, a delivery of the second current to the third valve 252 may regulate the third valve 252 such that the third valve 252 may supply fluid flow (e.g., a commensurate fluid flow) into the rod end chamber 204 based on which the second velocity of the member 160 (e.g., moldboard 164) may be attained.

In both the first embodiment and/or the second embodiment, to cause the delivery of the first current and/or the second current correspondingly to the first valve 212 and/or the third valve 252, the controller 220 may control an electrical power source (e.g., a battery or the like device) (not shown) such that the first current and/or second current may be delivered from such an electrical power source to the first valve 212 and/or the third valve 252, respectively. Although not limited, in both the first embodiment and the second embodiment, a regulation of the first valve 212 and/or the third valve 252 may mean altering of a position of spools (not shown) that may be associated with the first valve 212 and/or the third valve 252.

In some embodiments, the controller 220 may cause current (i.e., the first current and/or the second current) to be supplied to the first valve 212 (and/or the third valve 252) to increase fluid influx into the rod end chamber 204 based on the first velocity such that the member 160, e.g., the moldboard 164, may be raised with the second velocity. When doing so, the controller 220 may also detect a stoppage of the lowering of the milling drum 140 into the surface 108. In response to such stoppage, for example, the controller 220 may arrest a supply of the current (e.g., the first current and/or the third current) to the first valve 212 (and/or the third valve 252). In so doing, the controller 220 may restrict fluid influx (e.g., further fluid influx) into the rod end chamber 204 so as to halt a movement of the actuator 176 and cause the movement of the member 160, e.g., the moldboard 164, to the raised position, to be paused and/or altogether stopped.

In some embodiments, the controller 220 may determine the magnitude of the second velocity by sourcing data from the actuation sensor 208 (e.g., similarly to how the magnitude of the first velocity is determined), and, in some cases, may also check of any variation between the magnitude of the second velocity and the magnitude of the first velocity. In case the variation between the magnitude of the second velocity and the magnitude of the first velocity is beyond a threshold magnitude, the controller 220 may also suitably alter the first current and/or the second current, as applicable, to ensure that the variation between the magnitude of the second velocity and the magnitude of the first velocity is reduced (e.g., as much as possible) during the lowering of the milling drum 140.

The first embodiment and the second embodiment, as suitably usable by the machine 100, provide for a raising of the member 160, e.g., the moldboard 164, at the about same time or in concomitance to the lowering of the machine frame 112 and/or the milling drum 140 into the surface 108. By way of moving the member 160 (e.g., the moldboard 164) to the raised position with the second velocity (which may be equal to or which may be within the permissible range so as to be as close to the first velocity as possible), the hydraulic system 184, 184` ensures that the member 160, e.g., the moldboard 164, does not interfere with either the surface 108 or any part of the machine 100, in turn adequately clearing the milling drum 140 to reach up to its target depth of cut during the lowering process or the lowering of the milling drum 140. In other words, since the second velocity may match or closely match (i.e., to be equal to or be within the permissible range of) the first velocity, the hydraulic system 184, 184` helps prevent the member 160, e.g., the moldboard 164, from binding with the surface 108 or with other members of the enclosure assembly 152 during the lowering process. Moreover, because the second velocity may match or closely match with the first velocity, the moldboard 164 also prevents the milled materials to escape from the volume 156 during the lowering of the milling drum 140.

Unless explicitly excluded, the use of the singular to describe a component, structure, or operation does not exclude the use of plural such components, structures, or operations or their equivalents. The use of the terms “a” and “an” and “the” and “at least one” or the term “one or more,” and similar referents in the context of describing the disclosure, especially in the context of the following claims, are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B” or one or more of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B; A, A and B; A, B and B), unless otherwise indicated herein or clearly contradicted by context. Similarly, as used herein, the word "or" refers to any possible permutation of a set of items. For example, the phrase "A, B, or C" refers to at least one of A, B, C, or any combination thereof, such as any of: A; B; C; A and B; A and C; B and C; A, B, and C; or multiple of any item such as A and A; B, B, and C; A, A, B, C, and C; etc.

It will be apparent to those skilled in the art that various modifications and variations can be made to the method or system of the present disclosure without departing from the scope of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the method or system disclosed herein. It is intended that the specification and examples be considered as examples only, with a true scope of the disclosure being indicated by the following claims and their equivalent.