CN115053074A

CN115053074A - Hydraulic power unit with submersible motor

Info

Publication number: CN115053074A
Application number: CN201980103539.0A
Authority: CN
Inventors: C·N·金; J·温切
Original assignee: Kti Hydraulics
Current assignee: Kti Hydraulics
Priority date: 2019-12-14
Filing date: 2019-12-14
Publication date: 2022-09-13
Also published as: WO2021118607A1; EP4065851A1; EP4065851A4

Abstract

A Hydraulic Power Unit (HPU) having a submersible motor is provided for moving hydraulic fluid between a first chamber and a second chamber of a hydraulic device. The HPU may include a tank for storing hydraulic fluid, wherein the tank contains: an electric machine submerged in the hydraulic fluid, the electric machine having an energized configuration and a de-energized configuration based on at least one command signal; and a pump submerged in the hydraulic fluid and connected to the motor, wherein the motor drives the pump to introduce and withdraw the hydraulic fluid into and out of the tank.

Description

Hydraulic power unit with submersible motor

Technical Field

The present invention relates generally to hydraulic technology and, more particularly, to a hydraulic power unit having a submersible motor.

Background

Hydraulics is a technique that involves the use of liquids (e.g., hydraulic fluids) in mechanical performance applications. At its core, hydraulic pressure may be generated, controlled, and transmitted power through the use of pressurized hydraulic fluid. Typically, hydraulic fluid is the medium in a hydraulic device and/or system that transmits power. Common hydraulic fluids may be based on mineral oil or water. In practice, hydraulic devices and/or systems may be a core of various technologies such as, but not limited to, hydraulic brakes, power steering systems, aircraft flight control systems, elevators, dump trucks, and various other machines.

Disclosure of Invention

The hydraulic power unit ("HPU") of the present invention has a submersible motor, also referred to as an "HPU", and various embodiments of the present invention include features, none of which is solely responsible for its desirable attributes. Without limiting the scope of the present embodiments, their more prominent features will now be discussed below. In particular, the HPU with submersible motor of the present invention will be discussed in the context of a hydraulic lift equipped truck bed (also referred to as a dump truck) or a dump truck trailer. However, the use of a dump truck/trailer is merely exemplary, and the present HPU with submersible motor may be used in a variety of hydraulic applications, according to various embodiments of the present invention, depending on the requirements of a particular hydraulic device and/or system. After considering this discussion, and particularly after reading the section entitled "detailed description of certain embodiments" one will understand how the features of this embodiment provide the advantages described herein.

One aspect of the present embodiments includes implementing that in current hydraulic power units other than the present embodiments, the hydraulic fluid can only be used to operate the attached hydraulic devices without utilizing various characteristics of the hydraulic fluid (e.g., thermal cooling, noise abatement, shielding, etc.). For example, in current hydraulic power units other than the present embodiment, the motor and/or pump may be exposed to harsh environments, causing degradation and/or damage due to the absence of a protective cover. In addition, the motor and/or pump may generate undesirable noise. In addition, the HPU takes up valuable space because the motor, pump and/or tank (also referred to as a "sump") are separate discrete components. The present embodiments address these issues by providing an HPU having a tank containing hydraulic fluid and configured to contain a motor and pump submerged in the hydraulic fluid therein. Thus, the present embodiment advantageously enables the electric machine to be submerged in the hydraulic fluid, thereby protecting the electric machine from moisture and foreign matter. Furthermore, the noise generated by the HPU can be significantly reduced, since the motor is submerged in the hydraulic fluid and enclosed in the tank. Furthermore, the HPU with submersible motor can operate at a more constant and lower temperature due to the heat transfer/cooling characteristics of the hydraulic fluid. Furthermore, because the motor and/or pump are contained within the tank, the size of the HPU may be significantly reduced (e.g., by 50% or more). The present embodiment provides these advantages and enhanced functionality, as described below.

In a first aspect, there is provided a Hydraulic Power Unit (HPU) for moving hydraulic fluid between a first chamber and a second chamber of a hydraulic device, the HPU comprising: a tank for storing hydraulic fluid, wherein the tank contains: an electric machine submerged in the hydraulic fluid, the electric machine having an energized and de-energized configuration based on at least one command signal; and a pump submerged in the hydraulic fluid and connected to the motor, wherein the motor drives the pump to introduce and withdraw the hydraulic fluid into and out of the tank.

In an embodiment of the first aspect, the HPU further comprises a manifold connected to the pump, wherein the manifold comprises: an A-port configured to be connected to a first chamber of a hydraulic device; a B port configured to be connected to a second chamber of a hydraulic device; a first solenoid valve connected to the tank, wherein the first solenoid valve is configured to transition between a plurality of positions based on at least one command signal; a second solenoid connected to the A port, wherein the second solenoid is configured to transition between a plurality of positions based on at least one command signal; and a first check valve having a closed end connected to the B port.

In another embodiment of the first aspect, the manifold is connected to the pump through a first opening in a first surface of the tank.

In another embodiment of the first aspect, in an initial state: the motor is in a power-off configuration; the second solenoid valve is in the first position, loading the control check valve, wherein the closed end of the control check valve is connected to the a port; and the first solenoid valve is in a first position, wherein the first position of the first solenoid valve connects the open end of the control check valve to the tank.

In another embodiment of the first aspect, hydraulic fluid entering the a-port from the first chamber is prevented from moving by the closing end of the control check valve, while hydraulic fluid entering the B-port from the second chamber is prevented from moving by the closing end of the first check valve.

In another embodiment of the first aspect, the at least one command signal is an up command signal, wherein: the second solenoid valve is in the first position, thereby charging the control check valve; the first solenoid valve is in a second position, wherein the second position of the first solenoid valve connects the pump to the open end of the control check valve; and the motor is in an energized configuration, powering the pump to direct hydraulic fluid from the tank to the a port.

In another embodiment of the first aspect, the hydraulic fluid exits the a-port into the first chamber of the hydraulic device, thereby placing the hydraulic device in the extended state.

In another embodiment of the first aspect, the hydraulic fluid is pushed out of the second chamber and is directed through: passing the closed end of the first check valve by overcoming the set point of the first check valve; and a first solenoid valve in a second position allowing hydraulic fluid to flow into the tank.

In another embodiment of the first aspect, the at least one command signal is a down command signal, wherein: the second solenoid valve is in a second position, thereby loading the one-way control connector; the first solenoid valve is in a first position, wherein the first position of the first solenoid valve connects the pump to the open end of the first check valve; and the motor is in an energized configuration, powering the pump to direct hydraulic fluid from the tank to the B port.

In another embodiment of the first aspect, the hydraulic fluid exits the B port into a second chamber of the hydraulic device, thereby placing the hydraulic device in the retracted state.

In another embodiment of the first aspect, the hydraulic fluid is pushed out of the first chamber and is directed through: a one-way control connector; and a first solenoid valve in a first position allowing hydraulic fluid to flow into the tank.

In another embodiment of the first aspect, the at least one command signal is received from an input device connected to the HPU.

In another embodiment of the first aspect, the input device is wirelessly connected to the HPU.

In another embodiment of the first aspect, the electric machine is a direct current machine.

In another embodiment of the first aspect, the motor is attached to an interior facing surface of the case.

In another embodiment of the first aspect, the motor is connected to the power source through at least one opening in the first surface of the housing.

In another embodiment of the first aspect, the motor is connected to the start solenoid valve through at least one opening in the first surface of the housing.

In another embodiment of the first aspect, the hydraulic fluid absorbs waste heat generated by the electric machine.

In another embodiment of the first aspect, the hydraulic fluid absorbs noise generated by the electric motor.

In another embodiment of the first aspect, the hydraulic device is a double acting hydraulic cylinder.

Drawings

Various embodiments of the HPU of the present application having a submersible motor will now be discussed in detail, with emphasis on advantageous features. These embodiments describe a novel and non-obvious HPU with a submersible motor shown in the drawings, which are for illustrative purposes only. These drawings include the following figures:

fig. 1 shows a dump truck utilizing a double acting hydraulic cylinder (which may also be referred to as a hydraulic cylinder or a cylinder) to lift a truck bed in accordance with an embodiment of the present invention.

Fig. 2A-2C illustrate hydraulic cylinders in various states relative to truck bed position according to an embodiment of the present invention.

Fig. 3A is a schematic diagram of an HPU having a submersible motor according to an embodiment of the present invention.

Fig. 3B is a schematic diagram illustrating a side view of a case of an HPU having a submersible motor according to an embodiment of the present invention.

Fig. 3C is a schematic top view of an HPU having a submersible motor according to an embodiment of the present invention.

Fig. 3D is a schematic diagram illustrating a rear view of an HPU with a submersible motor according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of an HPU with a submersible motor when the hydraulic cylinder is at rest (also referred to as a neutral or initial state) according to one embodiment of the present invention.

Fig. 5 is a schematic diagram of an HPU with a submersible motor when the hydraulic cylinder is lifting the truck bed, according to one embodiment of the present invention.

Fig. 6 is a schematic diagram of an HPU with a submersible motor when the hydraulic cylinder is lowering the truck bed, according to one embodiment of the present invention.

Detailed Description

The following detailed description describes the present embodiments with reference to the accompanying drawings. In the drawings, reference numerals denote elements of the present embodiment. These reference numerals are reproduced below in conjunction with a discussion of the features of the corresponding figures.

Turning now to the drawings, an HPU (also referred to as an "HPU") having a submersible motor according to an embodiment of the present invention is disclosed. In many embodiments, an HPU having a submersible motor may be connected to one or more hydraulic devices, such as, but not limited to, double acting hydraulic cylinders. In various embodiments, the HPU with submersible motor may be part of a larger hydraulic system. In many embodiments, an HPU having a submersible motor may include a tank for containing hydraulic fluid and configured to contain the motor and/or pump submerged in the hydraulic fluid. In many embodiments, the electric motor may power a pump for regulating the flow of fluid between various components in the hydraulic system, as described further below. In various embodiments, the HPU may also include a manifold having an a port and a B port to connect to a hydraulic device (e.g., a hydraulic cylinder), as described further below. In some embodiments, the HPU may also include a power source, such as, but not limited to, a battery, that provides power to the motor. In some embodiments, the HPU may be connected to an input device that provides at least one command signal to the HPU, as described further below. The hydraulic system utilizing a hydraulic cylinder according to embodiments of the present invention is discussed further below.

Dump truck with double-acting hydraulic cylinder

Various systems may use hydraulic cylinders to provide directional force using pressurized hydraulic fluid (also referred to as "fluid"). Typically, the hydraulic cylinder may comprise a cylinder barrel, wherein the piston is connected to a piston rod, which may move back and forth as the piston moves back and forth within the cylinder barrel. By connecting the piston rod to the outer structure, the force generated by the pressurized hydraulic fluid may be applied to the outer structure. In a double-acting hydraulic cylinder, the bore may include a first chamber (also referred to as a "blind end") and a second chamber (also referred to as a "rod end") separated by a piston, where the first chamber may have a first pressure level and the second chamber may have a second pressure level. As described further below, the first and second chambers may be connected by the HPU to a submersible motor configured to move hydraulic fluid between the first and second chambers.

Fig. 1 shows a dump truck utilizing hydraulic cylinders to lift the truck bed according to one embodiment of the present invention. The dump truck 100 may include a double acting hydraulic cylinder 102 for lifting a truck bed 104. The dump truck 100 may also include a frame 110 having a rod 112, the rod 112 being connected to one side (e.g., the blind end) of the hydraulic cylinder 102. Those of ordinary skill in the art will recognize that push-through and/or scissor cranes are two common methods of lifting truck beds (shown in FIG. 1 as a scissor crane). Further, the truck bed 104 may be connected to a frame 106, the frame 106 being attached to a lift arm having a first portion 114, a joint 116, and a second portion 118. In various embodiments, a piston rod may extend from a rod end of the hydraulic cylinder 102 and connect to the second portion 118 of the lift arm. In several embodiments, the lift arm may be configured to receive a force from the hydraulic cylinder 102 via a piston rod to raise or lower the truck bed 104, as described further below.

As described above, the double acting hydraulic cylinder may have two chambers (e.g., a first chamber and a second chamber) that may be connected to a submersible motor by an HPU for moving hydraulic fluid between the two chambers to raise and/or lower the truck bed 104. For example, the first chamber may have a first port (also referred to as a "bottom port") connected to a corresponding first port (also referred to as an "a port") of a manifold of the HPU for allowing hydraulic fluid to enter and exit the first chamber. Further, the second chamber may include a second port (also referred to as a "top port") connected to a corresponding second port (also referred to as a "B port") of the manifold of the HPU for allowing hydraulic fluid to enter and exit the second chamber.

Fig. 2A-2C illustrate double acting hydraulic cylinders in various states relative to truck bed positions in accordance with an embodiment of the present invention. Referring to fig. 2A, the truck bed 216 is in a horizontal state and the hydraulic cylinder 202 is in its initial state. In many embodiments, the hydraulic cylinder 202 may include a first chamber 204 and a second chamber 206 separated by a piston 208. The piston 208 may be connected to a piston rod 210, the piston rod 210 extending from the second chamber 206 to attach to a structural device, such as, but not limited to, a lift arm that may be connected to the truck bed 216 or directly to the truck bed 216. In addition, the first chamber 204 may have a first port connected to a first hydraulic line 212 (also referred to as a "first hose"), the first hydraulic line 212 being connected to an a port of an HPU having a submersible motor, as described further below. Similarly, the second chamber 206 may have a second port connected to a second hydraulic line 214 (also referred to as a "second hose"), the second hydraulic line 214 being connected to a B port of an HPU having a submersible motor, as described further below. In an initial state, the piston may be positioned such that the amount of hydraulic fluid in the first chamber 204 is less than the amount of hydraulic cylinder when operating. For illustrative purposes, the amount of hydraulic fluid in the first chamber 204 is shown to be relatively less than the amount of hydraulic fluid in the second chamber 206.

Referring to fig. 2B, hydraulic cylinder 202 may be used to lift (also may be referred to as "raise") truck bed 216. In such embodiments, hydraulic fluid may be transferred from second chamber 206 to first chamber 204 by an HPU (not shown), causing movement of piston 208, causing piston rod 210 to actuate (e.g., extend) and thus lift truck bed 216. During extension, the piston 208 may move such that the piston rod 210 extends out and away from the rod end of the hydraulic cylinder 202. In many embodiments, the raising process may be initiated by an operator providing input to the HPU through an input device. For example, as described further below, the operator may press an "up" button. The operator may stop the lift process by providing an input to the HPU, such as, but not limited to, releasing the up button. In such embodiments, the HPU may stop the movement of hydraulic fluid from the second chamber 206 to the first chamber 204, and thus the truck bed 216 may stop at a particular location.

Referring to fig. 2C, hydraulic cylinder 202 may be configured to lower truck bed 216. In such embodiments, hydraulic fluid may be transferred from the first chamber 204 to the second chamber 206 through an HPU (not shown), causing movement of the piston 208 such that the piston rod 210 retracts, thereby lowering the truck bed 216. During lowering, the piston 208 may move such that the piston rod 210 retracts toward the blind end of the hydraulic cylinder 202. In many embodiments, the lowering process may be initiated by an operator providing input to the HPU via an input device. For example, the operator may press a "down" button, as described further below. The operator may stop the lowering process by providing an input to the HPU, such as, but not limited to, releasing the down button. In such embodiments, the HPU may stop the movement of hydraulic fluid from the first chamber 204 to the second chamber 206, and thus the truck bed 216 may stop at a particular location.

Although a particular hydraulic system for a dump truck using double acting hydraulic cylinders is discussed above with respect to fig. 1-2C, various systems of various hydraulic devices may be used in accordance with embodiments of the present invention as may be appropriate for the requirements of a particular application. An HPU having a submersible motor according to embodiments of the present invention will be discussed further below.

HPU with submersible motor

An HPU having a submersible motor may include a tank for containing hydraulic fluid and configured to contain the motor submerged in the hydraulic fluid. In various embodiments, the submersible motor may be connected to a pump that is also submerged in the hydraulic fluid. In many embodiments, the motor may also be connected to a power source that provides power to the motor based on at least one command signal, as described further below. The submersible motor may drive a pump for regulating the flow of hydraulic fluid between various components in the hydraulic system. For example, a pump may be connected to a manifold having an a port and a B port to connect to a hydraulic device (e.g., a hydraulic cylinder). In many embodiments, the manifold may include a first solenoid valve and a second solenoid valve, each solenoid valve configured based on at least one command signal, as further described below.

Fig. 3A shows a perspective view of an HPU having a submersible motor according to an embodiment of the present invention. The HPU 300 may include a tank 302, the tank 302 configured to house a motor 308 for driving a pump 312, as further described below. In many embodiments, the motor 308 may be secured to an interior facing surface of the housing 302. In several embodiments, the motor 308 may be secured to the housing 302 using various securing devices 310 known to those of ordinary skill in the art. In various embodiments, the tank 302 may be made of various materials, such as, but not limited to, steel, cast aluminum, and/or any other suitable material known to one of ordinary skill in the art. In some embodiments, the case 302 may be manufactured by welding the various sides and components. In some embodiments, the housing 302 may be manufactured using a die casting process. In some embodiments, the case 302 may be manufactured using any combination of processes such as, but not limited to, welding and die casting. Further, the tank 302 may be constructed in various sizes depending on various factors such as, but not limited to, the size of the motor 308, the size of the pump 312, the particular hydraulic device used to connect to the HPU, the available space for a particular application, and the like. For example, the tank 302 may be constructed to contain 5 quarts, 10 quarts, 15 quarts, etc. of hydraulic fluid.

Referring to fig. 3A, the tank 302 may include a first opening, which may be covered by a cover 304, for filling the tank 302 with hydraulic fluid. In many embodiments, the cover 304 may also include a measuring wand 305 for measuring the amount of hydraulic fluid in the tank 302. The tank 302 may also include a second opening, which may be covered by a cover 306, for draining the hydraulic fluid 302 from the tank 302. In many embodiments, the cover 304 and the cover 306 may fit and/or mate with their respective openings in the case 302 in a manner known to those of ordinary skill in the art. For example, the

covers

304, 306 may open and close their respective openings using a threaded fitting or any other closure device and/or system known to one of ordinary skill. In some embodiments, the first opening may be located on a top surface of the tank 302 to take advantage of gravitational forces acting on the hydraulic fluid when filling the tank 302 with hydraulic fluid. In some embodiments, the second opening may be located on a side surface of the tank 302 and located closer to the bottom surface to take advantage of gravity acting on the hydraulic fluid when the hydraulic fluid is drained from the tank 302. Tank 302 may be filled with various levels of hydraulic fluid as long as motor 308 and/or pump 312 are submerged in water. For example, in some embodiments, the tank may be 80% filled with hydraulic fluid. In some embodiments, the amount of hydraulic fluid may depend on the hydraulic fluid capacity of the hydraulic device connected to the HPU. For example, when operating a 2 inch cylinder or a 5 inch cylinder, the tank 302 may be filled to different capacities.

With further reference to fig. 3A, HPU 300 may also include a manifold 320, manifold 320 connected to pump 312 by a connector 322, as described further below. In many embodiments, the connector 322 may be hollow, allowing hydraulic fluid to move between the tank 302 (via the pump 312) and the manifold 320, as described further below. Manifold 320 may include an a-port connected to a first chamber of a hydraulic cylinder and a B-port connected to a second chamber of the hydraulic cylinder, as described further below. In many embodiments, HPU 300 may also include an electrical box 314, which electrical box 314 is connected to motor 308 via

connectors

316, 318 to place motor 308 in various configurations (e.g., powered on or powered off configurations), as described further below. For example, in some embodiments, the electrical box 314 may house an activation solenoid and/or a battery. In some embodiments, the activation solenoid and/or the battery may be housed separately and outside 314 the electrical box. In some embodiments, the

connectors

316, 318 may include a material that repels hydraulic fluid to increase longevity. For example, the

connectors

316, 318 may be made using a nitrile rubber (i.e., Buna-N) material or the like.

Fig. 3B shows a side view schematic of the interior of the HPU case, according to one embodiment of the present invention. As described above, tank 302 may be configured to house submersible motor 308 connected to submersible pump 312. For example, the pump 312 may be coupled to the motor 308 via

nuts

332, 334. In some embodiments, the pump 312 may also be connected to the motor 308 by a coupling 330 that couples the motor 308 to a shaft of the pump 312. For example, the coupling 330 may be a hex coupling or the like. In addition, the pump 312 may be connected to the manifold 320 by a connector 322. In some embodiments, the connector 322 may include a set screw 338 to connect the connector 322 to the pump 312. In some embodiments, the mounting screws 338 may comprise copper and/or aluminum or any other material suitable for a hydraulic fluid environment. In some embodiments, the pump 312 may include an opening 336 for accessing the hydraulic fluid in the tank 302.

Referring to fig. 3B, the pump 312 may be a hydraulic gear pump and the motor 308 may be a Direct Current (DC) electric motor 308. In operation, the motor 308 may rotate the pump 312, and the pump 312 may take hydraulic fluid from the tank 302 via the opening 336 and push the hydraulic fluid out of the tank 302 for movement of the hydraulic fluid between the first and second chambers of the attached hydraulic cylinder via the manifold 320, as further described below.

Fig. 3C shows a schematic HPU top view according to an embodiment of the present invention. As described above, the HPU may include a manifold 320, and the manifold 320 may include an a-port 350, with the a-port 350 connected to a corresponding bottom port of the hydraulic cylinder by a first hose. Also, as described above, the manifold 320 may include a B-port 352, with the B-port 352 connected to a corresponding top port of the hydraulic cylinder by a second hose. In many embodiments, the HPU may receive at least one command signal from an input device connected to the electrical box 314 and/or the manifold 320. For example, the input device may include an up button and/or a down button. In many embodiments, the up button may provide an up command signal that configures the HPU to raise the truck bed, while the down button may provide a down command signal that configures the HPU to lower the truck bed. In some embodiments, the input device may be directly connected (e.g., by a wire) to the HPU and/or may be wirelessly connected using various wireless communication protocols known to those skilled in the art, such as, but not limited to, bluetooth or WiFi.

With further reference to fig. 3C, the manifold 320 may include a first pressure relief valve 356, and the first pressure relief valve 356 may be normally closed, but may be configured to open when the pressure on the first pressure relief valve 356 reaches a valve set point. For example, the first pressure relief valve 356 may be an adjustable barrel pressure relief valve that may have an adjustable valve setting from 1 pound per square inch ("PSI") to 5000 PSI. The manifold 320 may also include a first solenoid valve 354, which first solenoid valve 354 may be switched between two or more positions based on the cylinder function (e.g., raise or lower) desired by the operator. For example, the first solenoid valve 354 may be a cartridge 4-way 2-position solenoid valve (or in some cases, a cartridge 4-way 3-position solenoid valve) that may be in a first position when raising the truck bed and a second position when lowering the truck bed, as further described below. In some embodiments, the first solenoid valve 354 may be a separate component connected to the manifold 320, or may be an integral part of the manifold 320.

With further reference to FIG. 3C, the manifold 320 may also include additional hydraulic components, such as, but not limited to, a second pressure relief valve (not shown), which may be a barrel pressure relief valve adjustable over a range of 1PSI to 5000 PSI. In addition, the manifold 320 may also include a first check valve (not shown). In addition, the manifold 320 may also include a second solenoid valve (not shown) (also referred to as a "cartridge a & B port load receiving solenoid valve"), as described further below. In various embodiments, the second solenoid valve may include a first position that allows the truck bed to remain in a stationary position (e.g., an initial state), be lowered, and/or be raised, as described further below.

Fig. 3D shows a back view schematic of an HPU according to an embodiment of the present invention. The tank 302 may be configured with a top surface 381, the top surface 381 having a plurality of openings to the interior of the tank 302. For example, the top surface 381 may have a first opening for filling the tank 302 with hydraulic fluid. In many embodiments, the first opening may be covered by the cover 304, as described above. Additionally, as described above, the top surface 381 may also have one or more openings to connect the manifold 320 with the pump 312 located inside the tank 302. Additionally, as described above, the top surface 381 may also have one or more openings to connect the electrical box 314 with the motor 308 located inside the housing 302.

Although a particular HPU having a submersible motor is discussed above with respect to fig. 3A-D, various HPUs having submersible motors, including HPUs having various hydraulic components, may be used according to embodiments of the present invention, as desired for particular applications. Further, although particular hydraulic components are shown as part of or connected to other components, various hydraulic components may be part of or connected to other components as desired for a particular application in accordance with embodiments of the present invention. Further, although particular hydraulic components are shown in particular locations, various hydraulic components may be placed in different locations according to embodiments of the present invention as required by particular applications. The HPU with submersible motor in an initial state according to an embodiment of the invention will be discussed further below.

HPU with submersible motor in initial state

As described above, the HPU may include a motor, a pump, a tank, and various hydraulic components for moving hydraulic fluid between the first and second chambers of the double-acting hydraulic cylinder. In the initial state, the HPU typically does not provide power to the hydraulic cylinders, and the truck bed is stationary in a fully lowered position.

Fig. 4 shows a schematic view of an HPU with a submersible motor according to an embodiment of the present invention in an initial state. A schematic diagram 400 of an HPU with submersible motor is shown connected to hydraulic cylinder 202 with truck bed 216 in a fully lowered position. As described above, the tank 412 contains hydraulic fluid and is configured to contain the motor 416 and/or pump 414 submerged in the hydraulic fluid. As described herein, the motor 416 may be connected to a power source (not shown), and when the motor 416 is in the energized configuration, the motor 416 may drive the pump 414 to push hydraulic fluid from the tank 412 out of the a-port 418 and/or the B-port 420, thereby moving hydraulic fluid between the first and second chambers of the hydraulic cylinder 202

Referring to fig. 4, in an initial state, the motor 416 is in a de-energized configuration and the pump 414 is not activated. In various embodiments, the pump 414 may be connected to the first pressure relief valve 402. The pump 414 may also be connected to the first solenoid valve 404 having a first position 404A and a second position 404B, as described further below. In an initial state, the first solenoid valve 404 may be in a first position 404A connecting the pump 414 to the open end (i.e., the free-flow direction end) of the first check valve 408. In many embodiments, the closed end (i.e., the blocked flow direction end) of the first check valve 408 may be connected to the B-port 420, wherein the B-port 420 may be connected to the second chamber of the hydraulic cylinder 202 by a second hose. In some embodiments, the closed end of the first check valve 408 may also be connected to a third barrel pressure relief valve 410, the third barrel pressure relief valve 410 being connected to a tank 412.

With further reference to fig. 4, the first chamber of the hydraulic cylinder 202 may be connected to the a-port 418 by a first hose. In many embodiments, the A port 418 may be connected to the second solenoid 406, wherein the second solenoid 406 may have a first position and a second position. In various embodiments, the first position may include loading the control check valve 406A for the second solenoid 406, and the second position may include loading the one-way control connector 406B for the second solenoid 406. In an initial state, the second solenoid valve 406 may be in a first position, connecting the A port 418 to the closed end of the control check valve 406A. In this configuration, the hydraulic cylinder 202 remains stationary because hydraulic fluid in the first chamber is prevented from moving by the closed end of the control check valve 406A and hydraulic fluid in the second chamber is prevented from moving by the closed end of the first check valve 408 and the second relief valve 410.

Although a particular HPU with submersible motors in an initial state for a dump truck is discussed above with respect to fig. 4, an HPU with submersible motors may be used for various hydraulic systems according to embodiments of the present invention, as desired for a particular application. Further, although various components (e.g., tanks, pumps, valves) are discussed above with reference to FIG. 4, any of a variety of components may be utilized according to embodiments of the present invention, as desired for a particular application. For example, the various components discussed above with respect to FIG. 4 may be interchanged as appropriate to the requirements of a particular application, in accordance with embodiments of the present invention. Further, while specific valve settings are discussed above with reference to FIG. 4, various valve settings may be utilized according to embodiments of the present invention depending on the requirements of a particular application. The use of an HPU with a submersible motor to raise and lower a truck bed in accordance with embodiments of the present invention will be discussed further below.

Raising and lowering a truck bed using a HPU with submersible motor

An HPU with a submersible motor may be configured to activate a hydraulic cylinder to raise or lower the truck bed. For example, a submersible motor may drive a submersible pump to transfer hydraulic fluid between a first chamber and a second chamber of a hydraulic cylinder to raise or lower a truck bed. In many embodiments, the hydraulic cylinder may raise or lower the truck bed based on at least one command signal received from the input device. For example, an operator may use an input device to provide an up command signal to raise the truck bed. Further, the operator may use the input device to provide a lower command signal to lower the truck bed. As described further below, the at least one command signal may place the motor in a de-energized configuration or an energized configuration. Further, the at least one command signal may place the first solenoid in the first position or the second position. Likewise, the at least one command signal may place the second solenoid in the first position or the second position.

Fig. 5 shows a schematic diagram of an HPU with submersible motor for raising a truck bed in accordance with an embodiment of the present invention. In many embodiments, the raising of the truck bed may be initiated by the HPU receiving an up command signal, as described above. In various embodiments, the up command signal may place the first solenoid 404 in the second position 404B. Additionally, the up command signal may place the second solenoid valve 406 in the first position, thereby charging the control check valve 406A.

Referring to fig. 5, a schematic diagram 500 of the HPU is shown connected to the hydraulic cylinder 202 that raises the truck bed 216. In many embodiments, the submersible motor 416 may be energized and the pump 414 driven by rotating the pump 414 and directing fluid from the tank 412 to the first solenoid valve 404 in the second position 404B. For example, in response to a command signal (e.g., an up command signal), the first solenoid valve 404 may be energized and transitioned from the first position 404A to the second position 404B. In the second position 404B, the HPU may allow hydraulic fluid from the pump 414 to be directed to the open end of the control check valve 406A of the second solenoid 406 in its first position. The hydraulic fluid may then exit the a-port 418 through a first hose connecting the a-port 418 to the hydraulic cylinder 202. Thus, hydraulic fluid may enter through the blind end of the cylinder and exert a force on the piston to extend the piston rod, thereby raising the truck bed 216.

With further reference to fig. 5, hydraulic fluid in the second chamber of the hydraulic cylinder 202 may move to the tank 412. In many embodiments, hydraulic fluid from the second chamber may be pushed out of the hydraulic cylinder 202 through a second hose connected to the B-port 420. In such an embodiment, as described above, hydraulic fluid may be directed through the closed end of first check valve 408 by overcoming the valve setting of first check valve 408. The hydraulic fluid may then flow through the first solenoid valve 404 in the second position 404B, allowing the hydraulic fluid to return to the tank 412.

Fig. 6 shows a schematic diagram of an HPU with a submersible motor when the hydraulic cylinder is lowering the truck bed, in accordance with an embodiment of the present invention. In many embodiments, the lowering of the truck bed may be initiated by the HPU receiving a down command signal, as described above. In various embodiments, the down command signal may place the first solenoid valve 404 in the first position 404A. Additionally, the down command signal may place the second solenoid valve 406 in a second position, thereby loading the one-way control connector 406B.

Referring to fig. 6, a schematic 600 of the power plant is shown connected to the hydraulic cylinder 202 that lowers the truck bed 216. In many embodiments, the down command signal may place the motor 416 in an energized configuration, thereby driving the pump 414 and directing fluid from the tank 412 to the first solenoid valve 404 in the first position 404A. For example, in various embodiments, the down command signal may energize the first solenoid valve 404, transition the first solenoid valve 404 from the second position 404B to the first position 404A, and allow hydraulic fluid to flow from the pump 414 and be directed to the open end of the first check valve 408. The hydraulic fluid may then exit the B-port 420 through a second hose connecting the B-port 420 to a second chamber of the hydraulic cylinder 420. Thus, hydraulic fluid may enter through the rod end of the cylinder and exert a force on the piston to retract the piston rod, thereby lowering the truck bed 216.

With further reference to fig. 6, the hydraulic fluid in the first chamber may be pushed out and returned to the tank 412. For example, hydraulic fluid from the first chamber may be pushed out of the first chamber through a first hose connected to the a-port 418. In such an embodiment, the second solenoid valve 406 may be in a second position (i.e., loading the one-way control connector 406B) that allows hydraulic fluid to flow through the one-way control connector 406B, directing hydraulic fluid to the first solenoid valve 404 in its first position 404A. In various embodiments, the first position 404A of the first solenoid 404 directs hydraulic fluid back to the tank 412.

Although a particular HPU with a submersible motor for raising and lowering a truck bed is discussed above with respect to fig. 5-6, various HPUs with submersible motors may be used for various hydraulic systems according to particular application requirements, in accordance with embodiments of the present invention. Further, although various components (e.g., tanks, pumps, valves) are discussed above with reference to fig. 5-6, any of a variety of components may be utilized according to embodiments of the present invention, depending on the requirements of a particular application. For example, the various components discussed above with respect to fig. 5-6 may be interchanged as appropriate to the requirements of a particular application, in accordance with embodiments of the present invention. Further, while specific valve settings are discussed above with reference to fig. 5-6, a variety of valve settings suitable to the requirements of a particular application may be utilized in accordance with embodiments of the present invention.

While the above description contains many specificities of the invention, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one embodiment thereof. It is therefore to be understood that the invention may be practiced otherwise than as specifically described without departing from the scope and spirit of the present invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

1. A Hydraulic Power Unit (HPU) for moving hydraulic fluid between a first chamber and a second chamber of a hydraulic device, the HPU comprising:

a tank for storing hydraulic fluid, wherein the tank contains:

an electric machine submerged in the hydraulic fluid, the electric machine having an energized and de-energized configuration based on at least one command signal; and

a pump submerged in the hydraulic fluid and connected to the motor, wherein the motor drives the pump to direct the hydraulic fluid into and out of the tank.

2. The HPU of claim 1, further comprising a manifold connected to the pump, wherein the manifold comprises:

an A port configured to connect to the first chamber of the hydraulic device;

a B port configured to connect to the second chamber of the hydraulic device;

a first solenoid valve connected to the tank, wherein the first solenoid valve is configured to transition between a plurality of positions based on at least one command signal;

a second solenoid connected to the A port, wherein the second solenoid is configured to transition between a plurality of positions based on the at least one command signal;

and

a first check valve having a closed end connected to the B-port.

3. The HPU of claim 2, wherein the manifold is coupled to the pump through a first opening in a first surface of the tank.

4. The HPU of claim 2, wherein, in an initial state:

the motor is in a power-off configuration;

the second solenoid valve is in a first position, thereby loading the control check valve, wherein the closed end of the control check valve is connected to the A-port; and is

The first solenoid valve is in a first position, wherein the first position of the first solenoid valve connects the open end of the control check valve to the tank.

5. The HPU of claim 4, wherein the hydraulic fluid entering the A-port from the first chamber is prevented from moving by the closed end of the control check valve, and the hydraulic fluid entering the B-port from the second chamber is prevented from moving by the closed end of the first check valve.

6. The HPU of claim 2, wherein the at least one command signal is an up command signal, wherein:

the second solenoid valve is in a first position, thereby charging the control check valve;

the first solenoid valve is in a second position, wherein the second position of the first solenoid valve connects the pump to the open end of the control check valve; and is

The motor is in an energized configuration, powering the pump to direct the hydraulic fluid from the tank to the A port.

7. The HPU of claim 6, wherein the hydraulic fluid exits the A-port into the first chamber of the hydraulic device, thereby placing the hydraulic device in an extended state.

8. The HPU of claim 7, wherein the hydraulic fluid is urged out of the second chamber and is directed through:

passing through the closed end of the first check valve by overcoming a set point of the first check valve; and

the first solenoid valve in the second position, thereby allowing the hydraulic fluid to flow into the tank.

9. The HPU of claim 2, wherein the at least one command signal is a down command signal, wherein:

the second solenoid valve is in a second position, thereby loading the one-way control connector;

the first solenoid valve is in a first position, wherein the first position of the first solenoid valve connects the pump to the open end of the first check valve; and is

The motor is in an energized configuration, powering the pump to direct the hydraulic fluid from the tank to the B-port.

10. The power unit as recited in claim 9 wherein the hydraulic fluid exits the B port into the second chamber of the hydraulic device, thereby placing the hydraulic device in a retracted state.

11. The HPU of claim 10, wherein the hydraulic fluid is pushed out of the first chamber and directed through:

the one-way control connector; and

the first solenoid valve in the first position, thereby allowing the hydraulic fluid to flow into the tank.

12. The HPU of claim 2, wherein the at least one command signal is received from an input device connected to the HPU.

13. The HPU of claim 12, wherein the input device is wirelessly connected with the HPU.

14. The HPU of claim 1, wherein the motor is a direct current motor.

15. The HPU of claim 1, wherein the motor is attached to an interior facing surface of the case.

16. The HPU of claim 1, wherein the motor is connected to a power source through at least one opening in the first surface of the case.

17. The HPU of claim 16, wherein the motor is connected to an activation solenoid through the at least one opening in the first surface of the tank.

18. The HPU of claim 1, wherein the hydraulic fluid absorbs waste heat generated by the electric machine.

19. The HPU of claim 1, wherein the hydraulic fluid absorbs noise generated by the motor.

20. The HPU of claim 1, wherein the hydraulic device is a double-acting hydraulic cylinder.