Integrated assembly of electric motor, hydraulic pump and electronic drive device and associated cooling arrangement

Abstract

An exemplary assembly includes a main housing (108) having an interior chamber (110), an electric motor (102) disposed in the interior chamber of the main housing and having a motor rotor (114), a cooling inner ring (700) disposed in the interior chamber of the main housing surrounding the electric motor, the cooling inner ring (700) including one or more motor cooling fluid passages configured to receive cooling fluid from an external source of cooling fluid and to allow the cooling fluid to flow around the electric motor to cool the electric motor, a hydraulic pump (104) positioned within the main housing at least partially inside the motor rotor of the electric motor, and a housing (173) coupled to the main housing and including (i) an inverter board (202) disposed therein, and (ii) one or more inverter cooling fluid passages configured to allow cooling fluid from an external source to cool the inverter board.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 297,839, filed January 10, 2022, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] An electric motor may be used to drive a hydraulic pump. For example, an output shaft coupled to a rotor of the electric motor may be coupled to a shaft of the hydraulic pump such that rotation of the rotor can rotate a rotor of the hydraulic pump to provide fluid flow.

[0003] The electronic drive device, including the inverter and motor controller, is typically separate from the motor and connected to the wire windings of the stator of the electric motor via a cable. It may be desirable to have an assembly that integrates the hydraulic pump and electronic drive device with the electric motor. In this way, mechanical components, such as shafts, bearings, etc., can be shared between the hydraulic pump and the motor. It may also be desirable to properly support the electric motor and hydraulic pump components and keep them lubricated to extend the life of the assembly.

[0004] Typically, a hydraulic system may have a system controller that controls the actuators in addition to the controllers for the electric motor and hydraulic pump. Thus, multiple controllers may communicate with each other via cables and signals connecting the controllers. Thus, it may be desirable to configure the electronic drive device of the assembly to receive actuator sensor information related to the actuator driven by the hydraulic pump, so that the electronic drive device can control the electric motor and hydraulic pump to achieve the commanded movement of the actuator. In this way, the system controller can be integrated with the electric motor controller to form a single controller, avoiding having cables, buses or signals between each separate controller.

[0005] During operation, heat may be generated that may damage components of the assembly. It may be desirable to cool the components of the electric motor. Additionally, it may be desirable to cool the electronic drive devices (e.g., inverters) since they may generate a large amount of heat during operation.

[0006] It is with respect to these and other issues that the disclosure herein is presented for consideration. Summary of the Invention

[0007] The present disclosure describes embodiments of a system of integrated electric motor, hydraulic pump and electronic drive device assemblies and associated cooling arrangements.

[0008] In a first exemplary embodiment, the present disclosure describes an assembly including a main housing having an interior chamber, an electric motor disposed in the interior chamber of the main housing and having a motor rotor, a cooled inner ring disposed in the interior chamber of the main housing surrounding the electric motor, the cooled inner ring comprising one or more motor cooling fluid passages configured to receive cooling fluid from an external source of cooling fluid and to allow the cooling fluid to flow around the electric motor to cool the electric motor, a hydraulic pump positioned within the main housing at least partially inside the motor rotor of the electric motor, and a housing coupled to the main housing and comprising: (i) an inverter board disposed therein; and (ii) one or more inverter cooling fluid passages configured to allow cooling fluid from an external source to cool the inverter board.

[0009] In a second exemplary embodiment, the present disclosure describes a hydraulic system comprising an actuator having a first chamber and a second chamber, a valve assembly configured to control fluid flow to and from the first and second chambers of the actuator, and the assembly of the first exemplary embodiment.

[0010] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features will become apparent by reference to the drawings and the detailed description that follows.

[0011] The novel features believed characteristic of the illustrative examples are set forth in the appended claims. However, the illustrative examples, as well as the preferred modes of use, further objects and the description thereof, can best be understood by reference to the following detailed description of illustrative examples of the present disclosure, read in conjunction with the accompanying drawings. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view of an assembly according to an exemplary embodiment. [Diagram 2] 2 is a cross-sectional side view of the assembly of FIG. 1 in accordance with an exemplary embodiment. [Diagram 3] FIG. 2 is an exploded perspective view of the assembly of FIG. 1 according to another exemplary embodiment. [Figure 4A] FIG. 3 is a cross-sectional view of FIG. 2 according to an exemplary embodiment. [Figure 4B] FIG. 1 is a detailed cross-sectional view of a pump drive shaft supporting a motor rotor according to an exemplary embodiment. [Diagram 5] FIG. 2 is a perspective view of the assembly of FIG. 1 illustrating cooling fluid paths according to an exemplary embodiment. [Figure 6A] FIG. 2 is a partial perspective view of the assembly of FIG. 1 showing an inverter cover and a backplate according to an exemplary embodiment. [Figure 6B] FIG. 2 is a partial exploded perspective view of the assembly of FIG. 1 showing an inverter cover and a backplate according to an exemplary embodiment. [Figure 7A] 2 is a partial perspective view of the assembly of FIG. 1 showing a main housing and a cooling inner ring disposed within the main housing according to an exemplary embodiment. [Figure 7B] 2 is a partially exploded perspective view of the assembly of FIG. 1 showing a main housing and a cooling inner ring according to an exemplary embodiment. [Figure 8] FIG. 13 is a perspective view of another cooling inner ring according to an exemplary embodiment; [Figure 9] FIG. 13 is a perspective view of another cooling inner ring according to an exemplary embodiment; [Figure 10] FIG. 13 is a perspective view of another cooling inner ring according to an exemplary embodiment; [Figure 11] FIG. 2 illustrates a hydraulic system including the assembly of FIG. 1 operating in an open circuit configuration, according to an exemplary embodiment. [Figure 12] FIG. 2 illustrates a hydraulic system having the assembly of FIG. 1 operating in a closed circuit configuration according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present disclosure relates to integrating or combining a hydraulic pump and an electronic drive device (including, for example, a motor controller and inverter) with an electric motor to provide a compact configuration in which the assembly reduces cost by sharing components, saves space, and increases reliability. The assembly also includes a cooling arrangement in which an external source provides a cooling fluid for cooling the electronic drive device and the electric motor.

[0014] The electric motor rotor is suitably supported at two points, its exterior and interior, providing enhanced support while allowing the hydraulic pump components to be located at least partially inside the rotor. The hydraulic pump drive shaft is drivingly connected to the electric motor rotor through a splined connection which is maintained in a lubricated and sealed condition, thereby improving the life and performance of the assembly.

[0015] Fig. 1 illustrates a perspective view of assembly 100 according to an exemplary embodiment, Fig. 2 illustrates a cross-sectional side view of assembly 100 according to an exemplary embodiment, and Fig. 3 illustrates an exploded perspective view of assembly 100 according to an exemplary embodiment. Figs. 1 to 3 will be described together.

[0016] The assembly 100 comprises an electric motor 102, a hydraulic pump 104 and an electronic drive device 106 integrated together. The assembly 100 includes a main housing 108 having an interior chamber 110 in which the components of the electric motor 102 and the hydraulic pump 104 are disposed.

[0017] The electric motor 102 includes a stator 112 that is stationarily positioned within an interior chamber 110 of the main housing 108. The stator 112 is configured to generate a magnetic field. In particular, the stator 112 may include wire windings (not shown) wrapped around a body (e.g., a lamination stack) of the stator 112 such that a magnetic field is generated when an electric current is supplied through the wire windings.

[0018] The electric motor 102 further includes a motor rotor 114 positioned within the stator 112. The electric motor 102 may further include magnets 116 assembled to the motor rotor 114 within the annular space between the stator 112 and the motor rotor 114. In one example, the magnets 116 include two circumferential rows of magnets axially spaced apart from one another and arranged to surround the motor rotor 114, as shown in FIG.

[0019] The magnets 116 are configured to interact with the magnetic field generated by the stator 112 to rotate the motor rotor 114 and generate torque. In another exemplary embodiment, a different type of electric motor may be used that does not include permanent magnets.

[0020] The hydraulic pump 104 is mounted within the main housing 108 and at least partially mounted within the motor rotor 114 and stator 112 of the electric motor 102. The assembly 100 includes a pump port block 117 having an inlet port 118 and an outlet port 120. The pump port block 117 is coupled to the main housing 108 via a number of fasteners or bolts, such as bolts 121 (see FIGS. 1 and 3).

[0021] The hydraulic pump 104 may be configured, for example, as a vane pump. In particular, the hydraulic pump 104 includes a pump cover 124 and a vane cartridge 126. The vane cartridge 126 includes a pump housing 128, a pump rotor 130, vanes, such as vane 131 and vane 132, and a pump drive shaft 134.

[0022] The motor rotor 114 has a cylindrical portion 136 and a shaft portion 138. The shaft portion 138 is supported within an electronics housing 140 of the electronic drive device 106 via bearings 142 disposed around the outer surface of the shaft portion 138 of the motor rotor 114, allowing the motor rotor 114 to rotate relative to the main housing 108 and the electronics housing 140. Additionally, the pump drive shaft 134 provides additional support for the motor rotor 114.

[0023] Figure 4A illustrates a cross-sectional view of Figure 2 according to an exemplary embodiment, and Figure 4B illustrates a detailed cross-sectional view showing pump drive shaft 134 supporting motor rotor 114 according to an exemplary embodiment. In particular, Figure 4B is an enlarged view of the cross-sectional view of Figure 4A showing the interface between pump drive shaft 134 and main shaft portion 138 of motor rotor 114.

[0024] The pump drive shaft 134 is rotatably coupled to the motor rotor 114. Referring jointly to Figures 3 and 4B, the pump drive shaft 134 has splines 144 formed on an outer surface of the pump drive shaft 134 and configured to engage respective splines 146 formed on an inner surface of the main shaft portion 138 of the motor rotor 114. Thus, the motor rotor 114 is drivingly connected to the pump drive shaft 134 and configured to transmit rotational motion to the pump drive shaft 134 during operation of the assembly 100.

[0025] As mentioned above, the motor rotor 114, and in particular the main shaft portion 138 of the motor rotor 114, is supported on its outer surface via the bearing 142. Additionally, the pump drive shaft 134 has an upset 147 and a shoulder 148, as shown in FIG. 4B, which provide support for the inner surface of the main shaft portion 138 of the motor rotor 114. The motor rotor 114 is therefore supported at two areas or points, namely, at the outer surface of the motor rotor 114, an area supported by the bearing 142, and at the inner surface of the motor rotor 114, an area where the pump drive shaft 134 supports the motor rotor 114. With this arrangement, the pump drive shaft 134 provides an extended support for the motor rotor 114, preventing misalignment or twisting of the motor rotor 114 during operation.

[0026] During operation, as the motor rotor 114 rotates, the rotational motion of the motor rotor 114 is transferred to the pump drive shaft 134 by a splined engagement with the pump drive shaft 134. It may be desirable to maintain the splined engagement between the splines 146 and the splines 144 in a lubricated state. Such lubrication extends the life of the components of the assembly 100, such as the motor rotor 114 and the pump drive shaft 134. For example, grease may be used to lubricate the splined engagement between the splines 146 and the splines 144.

[0027] It may be desirable to maintain grease or any lubricating fluid in the area of ​​the splined engagement. Accordingly, assembly 100 includes a first seal 150 (e.g., an O-ring) disposed within a groove formed around the outer surface of pump drive shaft 134. Additionally, assembly 100 includes caps 152 inserted within shaft portion 138 of motor rotor 114, with caps 152 having second seals 154 (e.g., an O-ring) disposed within grooves formed around the outer surface of each of caps 152.

[0028] First seal 150 and second seal 154 are located on either side of splines 144, 146. Thus, any lubricant in the area of ​​spline engagement between splines 146 and 144 is sealed and remains between first seal 150 and second seal 154. This configuration may also prevent lubricant from leaking outside the area of ​​spline engagement.

[0029] 2-3, the assembly 100 further includes another bearing 156 disposed around an outer surface of the pump drive shaft 134 to provide support for the pump drive shaft 134. In particular, the bearing 156 is disposed between the outer surface of the pump drive shaft 134 and the inner surface of the pump cover 124 to allow the pump drive shaft 134 to rotate relative to the pump cover 124. The assembly further includes a shaft seal 158. The shaft seal 158 is also disposed between the outer surface of the pump drive shaft 134 and the inner surface of the pump cover 124 and is configured to prevent leakage of fluid from the hydraulic pump 104 into the electric motor 102.

[0030] 2, fluid received at inlet port 118 flows through a first supply passage 160 and a second supply passage 162. Fluid flows from first supply passage 160 to a pumping chamber 164. Fluid also flows from second supply passage 162 through an arched fluid passage 165 and an arched fluid passage 166 formed in vane cartridge 126, whereby fluid from first supply passage 160 meets at pumping chamber 164.

[0031] Having two supply passages instead of one advantageously increases the supply capacity to the hydraulic pump 104. Because more fluid is supplied to the hydraulic pump 104, the possibility of cavitation occurring is reduced or eliminated.

[0032] The pump rotor 130 is configured to be eccentrically supported within the pump housing 128, which may have a cycloidal inner surface. The pump rotor 130 is positioned adjacent to the inner wall of the pump housing 128, thereby forming a crescent shaped cavity therebetween. The vanes, e.g., vanes 131 and 132, fit within slots provided in the pump rotor 130.

[0033] As the pump drive shaft 134 rotates (as the motor rotor 114 rotates), the pump rotor 130 also rotates. As the pump rotor 130 rotates, centrifugal force, actuation pressure, push rods and / or springs urge the vanes 131, 132 radially outward toward the inner surface of the pump housing 128. Fluid is then forced or drawn from the pump chamber 164 through holes, such as hole 167 shown in FIG. 2, and into the pump housing 128. In particular, the fluid flows into pockets formed by the vanes 131, 132, the pump rotor 130 and the pump housing 128.

[0034] As the pump rotor 130 continues to rotate, the vanes 131, 132 force the fluid to the opposite side of the crescent cavity where it is forced through a discharge hole in the pump housing 128. The fluid is then forced to the outlet port 120 where it flows out of the assembly 100. The fluid is then delivered to an actuator that is fluidly connected to the assembly 100, as described below with respect to Figures 10-11.

[0035] A vane pump is used herein as an example for illustration purposes, of course other types of pumps may be used, for example gear pumps or piston pumps.

[0036] 3, electronics housing 140 is coupled to the main housing via bolts, such as bolt 168. Electronics housing 140 is further coupled to electronics housing cover 170 via a number of bolts, such as bolt 172. With this arrangement, electronics housing 140 and electronics housing cover 170 form an enclosure 173 within which the electronic boards and electronic components of electronic drive device 106 are disposed. Thus, electronic drive device 106 is integrated with electric motor 102 and hydraulic pump 104 in assembly 100.

[0037] The electronic drive device 106 may include one or more electronic boards, such as a controller board 200 and an inverter board 202, which are electrically connected to one another and axially offset as shown. The controller board 200 and the inverter board 202 may be configured as a printed circuit board (PCB). A PCB uses conductive tracks, pads, and other features etched from one or more layers of copper laminate to mechanically support and electrically connect electronic components (e.g., microprocessors, integrated chips, capacitors, resistors, etc.) on and / or between layers of a non-conductive substrate. The components are typically soldered onto the PCB, thereby electrically connecting them and mechanically securing them to the PCB.

[0038] The inverter board 202 may be separated from and coupled to the controller board 200 via standoffs, such as the standoffs 204 shown in FIG. 3. The inverter board 202 may include a number of bus bars that are electrically conductive and configured to receive direct current (DC) power and provide the power to components assembled to the inverter board 202.

[0039] As an example, DC power may be provided from a battery to the inverter board 202. With this configuration, the DC power is provided to a bus bar, which then transmits the power to other components of the inverter board 202.

[0040] The inverter board 202 may be configured as a power converter that converts DC power received by the inverter board 202 into three-phase alternating current (AC) power that may be provided to the wire windings of the stator 112 to drive the electric motor 102. For example, the inverter board 202 may include a semiconductor switching matrix mounted to the inverter board 202 and configured to be electrically connected to the positive DC terminal and the negative DC terminal. The inverter board 202 may further include a number of capacitors disposed in the axial space between the inverter board 202 and the controller board 200.

[0041] The semiconductor switching matrix may include any arrangement of semiconductor switching devices that supports conversion of DC to three phase power. For example, the semiconductor switching matrix may include three phases with bridge elements electrically connected to the input DC terminals and connected to the three phase AC output terminals.

[0042] In one example, the semiconductor switching matrix includes a plurality of transistors (e.g., insulated gate bipolar transistors or metal oxide semiconductor field effect transistors). These transistors can be switched between an enabled or "on" state and a disabled or "off" state, for example, via a pulse width modulated (PWM) signal provided by a microprocessor assembled to the controller board 200. The microprocessor may include one or more processors. The processor may include a general-purpose processor (e.g., an INTEL® single-core microprocessor or an INTEL® multi-core microprocessor) or a special-purpose processor (e.g., a digital signal processor, a graphics processor, or an application specific integrated circuit (ASIC) processor). The processor may be configured to execute computer readable program instructions (CRPI) to perform the operations described throughout this specification. The processor may be configured to perform hard-coded functions (e.g., via the CRPI) in addition to or in the alternative to software-coded functions.

[0043] When the transistors of the semiconductor switching matrix are enabled and disabled at specific times via PWM signals, an AC voltage waveform is generated at the AC output terminals. Thus, the voltage waveform at the AC output terminals is pulse width modulated and swings between a voltage potential DC+ and a voltage potential DC-. The AC voltage waveform is then provided to the wire windings of the stator 112 to drive the electric motor 102. The controller board 200 and the inverter board 202 may include a number of junctions to facilitate the transfer of signals and power between each other and to other components of the assembly 100 or to external components.

[0044] The electronic drive device 106 may include multiple sensors. For example, the electronic drive device 106 may include a temperature sensor configured to provide information indicative of the operating temperature of the electric motor 102 and / or the fluid temperature of the working fluid passing through the hydraulic pump 104. Another temperature sensor may be mounted on the inverter board 202 to indicate the temperature of the inverter board 202. The electronic drive device 106 may also include a Hall effect current sensor that provides information indicative of the current level in the windings of the stator 112.

[0045] The electronic drive device 106 may further include a pressure sensor indicative of the pressure level of the fluid inside the assembly 100. The electronic drive device 106 may also include a rotational position sensor configured to provide sensor information indicative of the angular position of the motor rotor 114 and the pump drive shaft 134. The rotational position sensor information may be used by the microprocessor controlling the electric motor 102 to control the speed and torque generated by the motor rotor 114 in a closed-loop feedback control arrangement.

[0046] For example, the controller board 200 may include a sensor chip or encoder 206 to be mounted near the shaft portion 138 of the motor rotor 114, as shown in FIG. 2. The encoder 206 may be configured to interact with a magnet 208 disposed within the cap 152. The encoder 206 is configured as an electromechanical device that converts the angular position or motion of the motor rotor 114 into an analog or digital output signal that is provided to a microprocessor that controls the electric motor 102. In an exemplary embodiment, to improve the accuracy of the sensor information provided by the encoder 206, the magnetic polarity of the magnet 208 is aligned or has the same orientation as the magnetic polarity of each of the magnets (i.e., magnets 116) of the electric motor 102.

[0047] 1-3, the electronic actuation device 106 may further include an electrical connector 210 configured as a hollow plastic component housing a number of conductor pins electrically connected to conductive tracks on the controller board 200. A connector socket (not shown) having female pins may be assembled to or inserted into the electrical connector 210 such that the conductor pins contact the female pins of the connector socket. Wires may be connected to the female pins to provide signals to and receive signals from the conductor pins of the electrical connector 210.

[0048] This configuration allows the electronic drive device 106 to receive various input and sensor signals via the electrical connector 210 and provide commands in response to the received information. For example, the electronic drive device 106 can receive command signals from a central controller or a machine input device (e.g., a joystick on a hydraulic machine such as a wheel loader, backhoe, or excavator) indicating a desired fluid pressure and fluid flow rate to be provided by the hydraulic pump 104. The electronic drive device 106 can then control the AC power provided to the stator 112 to generate a particular speed and torque at the pump drive shaft 134 to provide the desired fluid pressure level and flow rate. The electronic drive device 106 can also provide sensor signals (e.g., from the encoder 206) to another central controller via the electrical connector 210.

[0049] Thus, electronic drive device 106 can be used as a controller for assembly 100 and for the actuators controlled by assembly 100. In particular, electronic drive device 106 receives command inputs and sensor signals from sensors internal to assembly 100 and sensors associated with the actuators, and in response controls electric motor 102 and hydraulic pump 104 to achieve desired or commanded movement of the actuators.

[0050] During operation of the assembly 100, heat is generated by the electric motor 102 and distributed among several components inside the electric motor 102. For example, heat is generated inside the stator slot windings, stator end windings, stator laminations, rotor laminations, and rotor magnets or conductors due to losses. The distribution of the generated heat inside the components depends on the type of motor and the motor's operating conditions (torque / speed). The heat generated inside the electric motor 102 increases the internal temperature, making the coils of the electric motor 102 more susceptible to burning out. Therefore, it may be desirable to cool the electric motor 102 to prevent the temperature from exceeding a threshold safety temperature.

[0051] Additionally, during operation, as the inverter board 202 converts DC power to AC power, the inverter board 202 generates heat. This heat is added to the ambient temperature of the enclosure 173 formed by the electronics housing 140 and the electronics housing cover 170. The hotter the inverter board 202 and enclosure 173 are, the less AC power the inverter board 202 delivers. Therefore, it may be desirable to cool the enclosure 173 and the inverter board 202 as well. The assembly 100 is configured to receive a cooling fluid from an external source and deliver the cooling fluid to the enclosure 173 (e.g., the electronics housing cover 170) for cooling the inverter board 202 and to the main housing 108 for cooling the electric motor 102.

[0052] 5 illustrates a perspective view of assembly 100 showing cooling fluid paths according to an exemplary embodiment. Assembly 100 is configured to receive cooling fluid from an external source 500 of cooling fluid.

[0053] In one example, the external source 500 may be a pump that draws cooling fluid, such as water glycol, from a fluid reservoir and pushes the cooling fluid through the assembly 100. In another example, the external source 500 may be a separate hydraulic circuit included in a hydraulic system that includes the assembly 100 (e.g., see boost circuit 404 shown in FIG. 12 described below).

[0054] In another example, the external source 500 may be a hydraulic actuator (e.g., a hydraulic cylinder or a hydraulic motor) included in a hydraulic system, as described below with respect to Figure 11. In this example, a portion of the fluid discharged from the hydraulic actuator is pumped to the assembly 100 for cooling, while the remaining amount of fluid discharged from the hydraulic actuator flows to a fluid reservoir (e.g., a fluid tank).

[0055] Cooling fluid from an external source 500 is supplied via fluid line 502 (e.g., hose, tube, pipe, etc.) to a junction point 504. At this junction point 504, the cooling fluid is split or bifurcated such that a portion of the cooling fluid branches off to flow through fluid line 506 to motor cooling fluid inlet port 508 while another portion flows through flow control valve 510 to inverter cooling fluid inlet port 512.

[0056] The flow control valve 510 is configured to distribute the cooling fluid between the electric motor 102 and the electronic drive device 106. For example, a controller (e.g., a microprocessor of the controller board 200) may be configured to receive sensor information indicative of a temperature of the electric motor 102 and a temperature of the inverter board 202. Based on the sensor information, the controller determines whether to supply more cooling fluid to the electric motor 102 or the electronic drive device 106. Based on the determination, the controller provides a signal to the solenoid 514 to operate the flow control valve 510 to, for example, increase or decrease the fluid resistance in the path of the fluid supplied to the inverter cooling fluid inlet port 512. In this manner, the cooling fluid can be distributed between the electric motor 102 and the electronic drive device 106 based on the cooling demand.

[0057] In one example, the flow control valve 510 may be manually operated. In another example, the assembly 100 may not include the flow control valve 510.

[0058] Fluid supplied to inverter cooling fluid inlet port 512 circulates within enclosure 173 (e.g., through electronics housing cover 170), thereby absorbing heat generated by inverter board 202, and is then supplied to inverter cooling fluid outlet port 516, from which the cooling fluid is discharged into fluid line 518. Similarly, fluid supplied to motor cooling fluid inlet port 508 circulates around electric motor 102 (e.g., around main housing 108), thereby absorbing heat generated by electric motor 102, and is then supplied to motor cooling fluid outlet port 520, from which the cooling fluid is discharged into fluid line 522.

[0059] Fluid from fluid line 522 merges with fluid from fluid line 518 at junction 524, after which the fluid is provided to fluid line 526, which may be fluidly connected to a fluid reservoir. The fluid reservoir may be a fluid reservoir dedicated to cooling fluid or may be a fluid reservoir for the working fluid of the hydraulic system.

[0060] 5 may include multiple fittings, if desired. Additionally, while the fluid lines or paths for the cooling fluid and other components, such as flow control valve 510, are shown as being external to assembly 100, it is contemplated that at least some of the fluid paths or components may be incorporated within assembly 100.

[0061] Figure 6A illustrates a partial perspective view of assembly 100 showing electronics housing cover 170 and backplate 600 according to an exemplary embodiment, and Figure 6B illustrates a partial exploded perspective view of assembly 100 showing electronics housing cover 170 and backplate 600 according to an exemplary embodiment. Backplate 600 may be coupled to electronics housing cover 170 via a number of fasteners, such as fastener 601.

[0062] The enclosure 173 is configured to have one or more inverter cooling fluid passages for cooling the inverter board 202. For example, fluid provided from an external source 500 shown in FIG. 5 is provided to an inverter cooling fluid inlet port 512 (via a flow control valve 510), and the fluid is then provided to an inverter cooling fluid passage 602 formed in the electronics housing cover 170 and the backplate 600. For example, the fluid received at the inverter cooling fluid inlet port 512 may be provided to a first end 604 of the inverter cooling fluid passage 602 (e.g., an inlet opening in the backplate 600 is aligned with the first end 604). The cooling fluid then passes through the inverter cooling fluid passage 602 and then reaches a second end 606 of the inverter cooling fluid passage 602. The second end 606 may be aligned with an outlet opening in the backplate 600, which provides the fluid to an inverter cooling fluid outlet port 516.

[0063] As shown, the inverter cooling fluid passages 602 extend in a zigzag or loop pattern through the electronics housing cover 170, thus increasing the surface area for dissipating heat.

[0064] In one example, inverter cooling fluid passage 602 is formed only in electronics housing cover 170. In another example, a portion of inverter cooling fluid passage 602 is formed in electronics housing cover 170 and a corresponding portion of inverter cooling fluid passage 602 is formed in backplate 600. For example, as shown in FIG. 2, if inverter cooling fluid passage 602 comprises a cylindrical fluid path or conduit, half of the path may be formed in electronics housing cover 170 and a corresponding half of the path may be formed in backplate 600.

[0065] The electronics housing cover 170 may further include a seal groove 608 in which a seal (e.g., an O-ring) may be disposed. Such a seal is configured to seal the cooling fluid flowing through the inverter cooling fluid passage 602 to prevent leakage of the cooling fluid to an environment external to the assembly 100. That is, the fluid is contained at the interface between the electronics housing cover 170 and the backplate 600.

[0066] 6A-6B as being formed in electronics housing cover 170 and backplate 600, other configurations are possible. The cooling passages may be formed anywhere through enclosure 173 (i.e., in one or more of backplate 600, electronics housing cover 170, or electronics housing 140) to allow cooling fluid to circulate around inverter board 202 and absorb heat generated by inverter board 202.

[0067] 7A illustrates a partial perspective view of assembly 100 showing main housing 108 and cooled inner ring 700 disposed within main housing 108, according to an exemplary embodiment, and FIG. 7B illustrates a partial exploded perspective view of assembly 100 showing main housing 108 and cooled inner ring 700, according to an exemplary embodiment. Cooled inner ring 700 is retained within main housing 108 via a retaining pin, such as retaining pin 702. Retaining pin 702 is configured to extend into a hole fabricated in cooled inner ring 700 (see FIG. 2) to retain cooled inner ring 700 to main housing 108.

[0068] The cooling inner ring 700 is configured with one or more motor cooling fluid passages that provide a cooling path for cooling fluid received at the motor cooling fluid inlet port 508 of the main housing 108. In particular, as shown in FIG. 7B, the cooling inner ring 700 may have a plurality of arcuate protrusions or ridges, such as arcuate ridge 704, arcuate ridge 706, arcuate ridge 708, and arcuate ridge 710. The cooling inner ring 700 may also have another set of arcuate ridges opposite the arched ridges 704-710, forming a motor cooling fluid passage 712 therebetween, as shown in FIG.

[0069] Cooling fluid received through motor cooling fluid inlet port 508 is supplied to cooling inner ring 700 at an inlet end 714 of a motor cooling fluid passage 712. The cooling fluid then passes through a number of paths under pressure from the external source 500 that provided the cooling fluid. For example, the cooling fluid may pass through the motor cooling fluid passage 712 to an outlet end 716 of the motor cooling fluid passage 712.

[0070] Additionally, cooling fluid may pass through the outer surface of cooled inner ring 700, for example, through arcuate motor cooling fluid passages formed between arcuate ridges 704-710. Such arcuate motor cooling fluid passages provide parallel paths for cooling fluid to pass across the surfaces of arcuate ridges 704-710 while absorbing heat.

[0071] Under pressure from external source 500, cooling fluid passes through various paths or passages in cooling inner ring 700 to an outlet end 716 aligned with motor cooling fluid outlet port 520. The fluid then discharges from motor cooling fluid outlet port 520 and travels through fluid line 522 to merge with the cooling fluid that has passed through electronics housing cover 170, as described above with respect to FIG.

[0072] 7B shows the cooled inner ring 700 with parallel paths (e.g., arcuate passages between the arcuate ridges 704-710), the cooled inner ring 700 may be configured differently. For example, another cooled inner ring may have serial paths (e.g., a single spiral or zigzag motor cooling fluid passage). Another cooled inner ring may have protrusions of various shapes to increase the surface area for dissipating heat.

[0073] 8 illustrates a perspective view of another cooled inner ring 800 according to an exemplary embodiment. The cooled inner ring 800 has a spiral motor cooling fluid passage 802 formed as a looped recess around the outer surface of the cooled inner ring 800. The spiral motor cooling fluid passage 802 has an inlet end 804 aligned with the motor cooling fluid inlet port 508 to receive cooling fluid from the motor cooling fluid inlet port 508. The cooling fluid then circulates around the outer surface of the cooled inner ring 800, allowing the sides of the spiral motor cooling fluid passage 802 to increase the surface area for dissipating heat to the cooling fluid.

[0074] The fluid then reaches outlet end 806 which is aligned with motor cooling fluid outlet port 520. The fluid then exits motor cooling fluid outlet port 520 and travels through fluid line 522 to join the cooling fluid that has passed through electronics housing cover 170, as described above with respect to FIG.

[0075] 9 illustrates a perspective view of another cooled inner ring 900, according to an example embodiment. The cooled inner ring 900 has a number of protrusions 902 having a polygonal shape (e.g., a closed planar shape defined by straight sides, such as a square, pentagon, hexagon, etc.).

[0076] The protrusions 902 are longitudinally (i.e., along the longitudinal axis of the cooling inner ring 900) interposed between an inlet circular passage 904 and an outlet circular passage 906. The inlet circular passage 904 receives cooling fluid from the motor cooling fluid inlet port 508 which is discharged from the outlet circular passage 906 to the motor cooling fluid outlet port 520.

[0077] The configuration of the polygonal shaped protrusions 902 defines various cooling pathways between them. Fluid received at the motor cooling fluid inlet port 508 is fed into the inlet circular passage 904, where the cooling fluid is then spread across the various motor cooling fluid passages / paths defined between the protrusions 902. The multiple raised surfaces of each protrusion allow for increased surface area for heat dissipation and absorption by the cooling fluid.

[0078] Under pressure from external source 500, fluid is forced to diffuse through protrusions 902 and then to exit circular passage 906 aligned with motor cooling fluid exit port 520. The fluid then exits motor cooling fluid exit port 520 and travels through fluid line 522 to merge with the cooling fluid that has passed through electronics housing cover 170, as described above with respect to FIG.

[0079] 10 illustrates a perspective view of another cooled inner ring 1000 according to an exemplary embodiment. The cooled inner ring 1000 has a zigzag motor cooling fluid passage 1002 formed as a longitudinally extending recess that zigzags as it passes through the outer surface of the cooled inner ring 1000. The zigzag motor cooling fluid passage 1002 has an inlet end 1004 aligned with a motor cooling fluid inlet port for receiving cooling fluid therefrom.

[0080] Under pressure from an external source 500, the cooling fluid circulates and zigzags around the outer surface of the cooling inner ring 1000 as it passes through the zigzag motor cooling fluid passages 1002. The sides of the zigzag motor cooling fluid passages 1002 can increase the surface area for dissipating heat to the cooling fluid.

[0081] The fluid then reaches outlet end 1006 which is aligned with motor cooling fluid outlet port 520. The fluid then exits motor cooling fluid outlet port 520 and travels through fluid line 522 to join the cooling fluid that has passed through electronics housing cover 170, as described above with respect to FIG.

[0082] 2, the assembly 100 is shown with cooled inner ring 700. However, it will be appreciated that cooled inner rings 800, 900, 1000 may also be used.

[0083] Additionally, in another exemplary embodiment, the cooling passages may be formed inside the main housing 108. In this example, a cooling inner ring may not be used. Rather, the main housing 108 acts as a cooling jacket with cooling passages formed therethrough. Any other configuration that allows cooling fluid to circulate through the cooling fluid passages to surround the electric motor 102 and absorb heat generated by the electric motor 102 may be used.

[0084] 2, cooled inner ring 700 has outer annular grooves at both ends, such as annular groove 174 and annular groove 176. These annular grooves 174, 176 are configured to receive seals, such as O-rings (not shown), to seal the cooling fluid between main housing 108 and cooled inner ring 700.

[0085] Furthermore, the main housing 108 is assembled to the electronic device housing 140. The electronic device housing 140 has a cylindrical protrusion 178. The outer surface of the protrusion 178 is joined to the inner surface of the main housing 108. Another seal 180 disposed in an annular groove formed in the outer surface of the cylindrical protrusion 178 can further seal the cooling fluid from entering the interior chamber 110 in which the electric motor 102 is disposed.

[0086] As mentioned above, the external source of cooling fluid 500 may have a variety of configurations. The external source 500 may be a pump that draws cooling fluid, such as water glycol, from a fluid reservoir and pushes the cooling fluid through the assembly 100, or it may be another component or circuit of the hydraulic system in which the assembly 100 is used.

[0087] Fig. 11 illustrates a hydraulic system 300 including the assembly 100 operating in an open circuit configuration, according to an exemplary embodiment. In Fig. 11, the actuating fluid lines are shown as solid lines, while the command and sensor signals are shown as dashed lines. Also, not all signal lines are shown to reduce visual clutter in the drawing. A power source, such as a battery or generator, is configured to provide DC power to the assembly 100. To reduce visual clutter in the drawing, the power source is not shown.

[0088] The hydraulic system 300 also includes a fluid reservoir 302 capable of storing fluid at a low pressure, for example, between 0 and 70 pounds per square inch (psi). The inlet port 118 of the assembly 100 is fluidly connected to the fluid reservoir 302. Thus, the assembly 100 receives fluid from the fluid reservoir 302 through the inlet port 118 and then expels the fluid through the outlet port 120, as described above.

[0089] Hydraulic system 300 also includes a manifold or valve assembly 304. This valve assembly 304 may include fluid paths and a number of solenoid actuated valves (e.g., one or more directional control valves, flow control valves, load holding valves, etc.) that control the flow of fluid through such fluid paths.

[0090] In one example, the valve assembly 304 is coupled to the assembly 100. For example, the valve assembly 304 may be assembled to the pump port block 117. The valve assembly 304 may thus control the flow of fluid into the inlet port 118 and out of the outlet port 120.

[0091] The controller board 200 may include an electronic valve driver that controls the current and voltage signals provided to the solenoid coils of the solenoid actuated valves of the valve assembly 304 to control the actuation and state of operation of the solenoid valves. Thus, the electronic drive device 106 may be configured to control the state of operation of the solenoid actuated valves and the fluid flow through the valve assembly 304.

[0092] The valve assembly 304 is configured to direct fluid flow to and from an actuator 306. The actuator 306 includes a cylinder 308 and a piston 310 slidably received within the cylinder 308. The piston 310 includes a piston head 312 and a rod 314 that extends from the piston head 312 along a central longitudinal axis of the cylinder 308. The piston head 312 divides the interior space of the cylinder 308 into a first chamber 316 and a second chamber 318.

[0093] The electronic drive device 106 of the assembly 100 may receive input information, including sensor information, via signals from various sensors or input devices provided in the hydraulic system 300 and, in response, provide electrical signals to various components of the hydraulic system 300. For example, the electronic drive device 106 may receive actuator sensor information, i.e., the position x and velocity of the piston 310, from a position sensor and / or a velocity sensor connected to the piston 310.

number

[0094] As described above, the electronic drive device 106 may receive sensor information from sensors (e.g., encoder 206) of the assembly 100 indicative of the speed of the motor rotor 114, the pressure level of the fluid discharged from the hydraulic pump 104, the temperature of the cooling fluid, the temperature of the electric motor 102, the temperature of the inverter board 202, etc. The electronic drive device 106 may also receive inputs (e.g., from a machine joystick) indicative of a commanded or desired speed for the piston 310. The electronic drive device 106 can then provide signals to the electric motor 102 and valve assembly 304 of the assembly 100 to controllably move the piston 310 at the commanded desired speed.

[0095] For example, to eject the piston 310 (i.e., to move the piston 310 upward as viewed in FIG. 11 ), the electronic drive device 106 actuates the electric motor 102, which causes the hydraulic pump 104 to draw fluid from the fluid reservoir 302, through the inlet port 118, and then through the outlet port 120 to the valve assembly 304. The electronic drive device 106 also sends a command signal to one or more valves to operate the valve assembly 304 in a first state. As a result, pressurized fluid delivered from the assembly 100 through the outlet port 120 flows through the valve assembly 304 to the first chamber 316. As the piston 310 ejects, the fluid displaced from the second chamber 318 flows to the valve assembly 304, which directs the fluid to the fluid reservoir 302 via the return line 324. The electronic drive device 106 operates the electric motor 102 at a particular speed and torque to provide a particular flow rate at a particular pressure to the actuator 306 to move the piston 310 at a desired speed while controlling the pressure levels in the first chamber 316 and / or the second chamber 318.

[0096] To retract the piston 310, the electronic drive device 106 may send a command signal to one or more valves to operate the valve assembly 304 in a second state in which the valve assembly 304 directs fluid received from the outlet port 120 to the second chamber 318. As the piston 310 retracts, fluid in the first chamber 316 is forced out of the first chamber 316 and into the valve assembly 304, which directs the fluid through the return line 324 to the fluid reservoir 302.

[0097] With this configuration, whether the piston 310 is extended or retracted, the fluid discharged from the actuator 306 is supplied to the fluid reservoir 302 via the return line 324. At the same time, the fluid discharged from the actuator 306 is also used as a cooling fluid to reduce the temperature of the electric motor 102 and the inverter board 202.

[0098] In particular, fluid passing through return line 324 branches at junction 326 into cooling fluid line 328, which is fluidly connected to assembly 100 (e.g., via fluid line 502) as shown in FIG. 11 to supply cooling fluid to assembly 100. To provide cooling fluid at a particular desired pressure (e.g., 50 psi), hydraulic system 300 includes valve 330. Valve 330 is configured to allow a pressure level upstream of valve 330 (e.g., at junction 326) to be greater than the pressure level in fluid reservoir 302.

[0099] As an example, the valve 330 may be a relief valve that is pressure-set to a desired pressure level. In another example, the valve 330 may include an opening that restricts fluid flow through the opening, thus allowing the pressure level to be increased upstream. In another example, the valve 330 may include a spring-loaded check valve. Such a spring-loaded check valve may include a check element (ball or poppet) that is spring-loaded or biased to a closed position by a spring. When the pressure level upstream of the valve 330 reaches a preset pressure level that exceeds the force exerted by the spring on the check element, the valve 330 opens, allowing fluid to flow to the fluid reservoir 302. Thus, the fluid delivered through the cooling fluid line 328 has a preset pressure level set by the spring. The valve 330 may be a combination of the exemplary configurations described above, or any other valve configuration that allows the pressure level to be increased at the junction 326.

[0100] In another example, the valve 330 may be a proportional electronically actuated valve. In this example, a controller (e.g., controller board 200) may send a signal to an actuator (e.g., a solenoid) of the valve 330 to vary the pressure level upstream of the valve 330 based on cooling demand (e.g., to provide sufficient cooling for a particular situation). To reduce visual clutter in the drawings, the signal lines to the valve 330 are not shown.

[0101] The cooling fluid supplied to the assembly 100 via the cooling fluid line 328 then circulates through the main housing 108 (see Figures 7A-10) and the electronics housing cover 170 (see Figures 6A-6B) and then is supplied via fluid line 526 to the cooling fluid return line 332, which returns the cooling fluid to the fluid reservoir 302.

[0102] In one example, the electronic drive device 106 of the assembly 100 may receive sensor information indicative of the temperature of the electric motor 102 and the inverter board 202. In response, the electronic drive device 106 controls the solenoid 514 of the flow control valve 510 to distribute cooling fluid between the electric motor 102 (e.g., to the cooling inner rings 700, 800, 900, 1000) and the electronics housing cover 170, thereby maintaining the temperature of each of the electric motor 102 and the inverter board 202 below a safe operating temperature.

[0103] Hydraulic system 300 may be referred to as an open circuit or open loop system, in which assembly 100 draws fluid from a fluid reservoir 302 and then supplies the fluid to an actuator 306 through a valve assembly 304, where the fluid discharged from the actuator 306 returns to the fluid reservoir 302 through the valve assembly 304. Alternatively, assembly 100 may be used in a closed circuit configuration in which fluid is circulated in a loop between hydraulic pump 104 and actuator 306.

[0104] 12 illustrates a hydraulic system 400 having assembly 100 operating in a closed circuit configuration, according to an exemplary embodiment. Components of hydraulic system 400 that are similar to components of hydraulic system 300 are labeled with the same reference numbers.

[0105] In hydraulic system 400, hydraulic pump 104 of assembly 100 supplies fluid from outlet port 120 through valve assembly 402 to either first chamber 316 or second chamber 318, and fluid discharged from the other chamber of actuator 306 returns to inlet port 118 of assembly 100. Thus, fluid circulates between hydraulic pump 104 and actuator 306 of assembly 100.

[0106] Due to the configuration of the piston 310 with the rod 314 extending through the second chamber 318, the fluid flow rate of the fluid entering or being discharged from the first chamber 316 is greater than the fluid flow rate of the fluid entering or being discharged from the second chamber 318, respectively. The hydraulic system 400 includes an augmentation circuit 404 configured to increase the fluid flow rate or consume excess flow due to the difference between the fluid flow rate of the fluid supplied to or being discharged from the first chamber 316 and the fluid flow rate of the fluid supplied to or being discharged from the second chamber 318.

[0107] The augmentation circuit 404 may include, for example, a charge pump configured to draw fluid from the fluid reservoir 302 and provide an augmented fluid flow to an augmented flow line 406 fluidly connected to the valve assembly 402. The valve assembly 402 may include a valve that facilitates combining a make-up fluid flow from the augmented flow line 406 with fluid discharged from the second chamber 318 and thereafter providing the fluid to the inlet port 118 of the assembly 100 to increase the fluid flow rate into the inlet port 118 when the piston 310 is extended.

[0108] In another example, the augmentation circuit 404 may include an accumulator configured to store pressurized fluid and the fluid reservoir 302 may not be used. In another example, a hydraulic system may include multiple actuators and multiple assemblies similar to the assembly 100, and the augmentation circuit 404 may receive excess flow from another actuator and provide the excess flow as augmented flow to the actuator 306.

[0109] The augmentation circuit 404 may also be configured to receive excess fluid flowing through the augmentation flow line 406 and provide a path for such excess fluid to the fluid reservoir 302 (or another actuator in the system). In particular, when the piston 310 is retracted and the fluid expelled from the first chamber 316 exceeds the consumed fluid required by the second chamber 318, the excess flow is provided through the valve assembly 402 to the augmentation flow line 406 and then to the augmentation circuit 404, which directs the fluid flow to the fluid reservoir 302 (or another actuator in the system).

[0110] Additionally, in hydraulic system 400, augmentation circuit 404 may be further configured as an external source 500 that supplies cooling fluid to assembly 100. In particular, augmentation circuit 404 may supply cooling fluid through a cooling fluid line 408 that is fluidly connected to assembly 100 (e.g., fluid line 502).

[0111] In one example, the augmentation circuit 404 may be configured to supply pressurized fluid to the valve assembly 402 at a pressure level that is higher than a desired pressure level for the cooling fluid. For example, the augmentation circuit 404 may supply an augmented fluid flow at a pressure level of 400 psi, while the desired pressure level for the cooling fluid may be approximately 50 psi. In this case, the hydraulic system 400 may include a pressure reducing valve 410 configured to reduce the pressure level from 400 psi to 50 psi and supply the cooling fluid at the reduced pressure level downstream of the fluid line 502 that supplies the cooling fluid to the assembly 100.

[0112] The pressure reducing valve 410 is represented symbolically in FIG. 12 and is not meant to be limiting. A pilot operated pressure reducing valve may be used. Any valve or combination of components configured to reduce the pressure level of the fluid passing therethrough may be used.

[0113] The cooling fluid leaving pressure reducing valve 410 flows into fluid line 502 and then circulates through main housing 108 (see FIGS. 7A-10) and electronics housing cover 170 (see FIGS. 6A-6B). The cooling fluid is then fed through fluid line 526 to a cooling fluid return line that returns the cooling fluid to fluid reservoir 302. This cooling fluid return line is not shown in FIG. 12 to reduce visual clutter in the drawings. However, it will be appreciated that the cooling fluid discharged through fluid line 526 may be fed directly to fluid reservoir 302 or indirectly through valve assembly 402 and boost circuit 404.

[0114] As described above with respect to FIG. 11 , in an example, the electronic drive device 106 of the assembly 100 may receive sensor information indicative of the temperatures of the electric motor 102 and the inverter board 202 and, in response, may control the solenoid 514 of the flow control valve 510 to distribute cooling fluid between the electric motor 102 (e.g., to the cooling inner rings 700, 800, 900, 1000) and the electronics housing 170, thereby maintaining the temperatures of each of the electric motor 102 and the inverter board 202 below a safe operating temperature.

[0115] Numerous modifications may be made to the exemplary embodiment shown in FIGS. 1-10. For example, instead of coupling the main housing 108 to the electronic device housing 140 configured as a separate housing, both housings may be combined to form a single housing. As another example, a different type of pump may be used. Also, in another exemplary embodiment, a gearbox may be used to couple the motor rotor 114 to the pump drive shaft 134. Also, whereas the hydraulic pump 104 is partially located within the stator 112, in another exemplary embodiment, the pump may be located completely within the stator windings.

[0116] In the above detailed description, various features and operations of the disclosed system are explained with reference to the accompanying drawings. The exemplary embodiments described herein are not meant to be limiting. Certain aspects of the disclosed system may be arranged and combined in a wide variety of configurations, all of which are contemplated herein.

[0117] Moreover, unless the context suggests otherwise, features shown in each drawing may be used in combination with one another. Thus, the drawings should be considered generally as component aspects of one or more overall embodiments, and it should be understood that not all illustrated features are required for each embodiment.

[0118] Moreover, any recitation of elements, blocks, or steps in the specification or claims is for the purpose of clarity, and thus such recitation should not be construed as requiring or implying that these elements, blocks, or steps be adhered to in a particular arrangement or performed in a particular order.

[0119] Further, a device or system may be used or configured to perform the functions presented in the figures. In some cases, device and / or system components may be configured to perform the functions, whereby the components are in fact configured and organized (with hardware and / or software) to enable such performance. In other examples, device and / or system components may be adapted to perform a function, enable performance of a function, or be arranged such that they are suitable for performing a function, e.g., when operated in a particular manner.

[0120] The term "substantially" means that the recited characteristic, parameter or numerical value need not be achieved exactly, but rather deviations or variations including, for example, tolerances, measurement errors, measurement accuracy limits and other factors known to those skilled in the art may occur to an extent that does not interfere with the effect that the characteristic is intended to provide.

[0121] The arrangements described herein are for purposes of example only. Thus, one of ordinary skill in the art will recognize that other arrangements and other elements (e.g., machines, interfaces, operations, sequences and groupings of operations, etc.) may be used instead, and some elements may be omitted entirely, depending on the results desired. Furthermore, many of the described elements are functional entities that may be configured as separate or distributed components or in any suitable combination and location with other components.

[0122] Although various aspects and embodiments have been disclosed herein, other aspects and embodiments should be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes only and are not intended to be limiting, with the true scope being set forth in the following claims and the full scope of equivalents to which such claims are entitled. Additionally, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0123] Accordingly, embodiments of the present disclosure may relate to one of the exemplary embodiments (EEE) listed below.

[0124] EEE1 is an assembly comprising: a main housing having an interior chamber; an electric motor disposed in the interior chamber of the main housing and having a motor rotor; a cooled inner ring disposed in the interior chamber of the main housing surrounding the electric motor, the cooled inner ring comprising one or more motor cooling fluid passages configured to receive cooling fluid from an external source of cooling fluid and to allow the cooling fluid to flow around the electric motor to cool the electric motor; a hydraulic pump positioned within the main housing at least partially inside the motor rotor of the electric motor; and a housing coupled to the main housing and comprising: (i) an inverter board disposed therein; and (ii) one or more inverter cooling fluid passages configured to allow cooling fluid from the external source to cool the inverter board.

[0125] EEE2 is the assembly of EEE1, wherein the cooling inner ring includes a plurality of arcuate ridges defining one or more motor cooling fluid passages therebetween.

[0126] EEE3 is the assembly of EEE1 or EEE2, wherein the cooled inner ring includes a spiral or zigzag motor cooling fluid passage formed as a recess surrounding an outer surface of the cooled inner ring.

[0127] EEE4 is an assembly described in any one of EEE1 to 3, wherein the cooling inner ring has a plurality of protrusions, each of which has a polygonal shape, thereby forming one or more motor cooling fluid passages between the plurality of protrusions, thereby enabling cooling fluid to be diffused through the one or more motor cooling fluid passages.

[0128] EEE5 is the assembly of any one of EEE1 to EEE4, wherein the main housing comprises a motor cooling fluid inlet port configured to receive cooling fluid from an external source and supply cooling fluid to one or more motor cooling fluid passages of the cooling inner ring, and a motor cooling fluid outlet port configured to supply cooling fluid that has flowed through the one or more motor cooling fluid passages to a fluid reservoir.

[0129] EEE6 is an assembly described in any one of EEE1 to 5, wherein the housing comprises an electronic device housing coupled to the main housing and an electronic device housing cover coupled to the electronic device housing, whereby the housing is formed by the electronic device housing cover and the electronic device housing.

[0130] EEE7 is the assembly of EEE6, wherein the inverter board is assembled to the electronics housing cover, and one or more inverter cooling fluid passages are formed in the electronics housing cover.

[0131] EEE8 is the assembly of EEE7 further comprising a backplate coupled to the electronics housing cover, the backplate having (i) an inverter cooling fluid inlet port configured to receive cooling fluid from an external source and supply cooling fluid to one or more inverter cooling fluid passages formed in the electronics housing cover, and (ii) an inverter cooling fluid outlet port configured to receive cooling fluid that has flowed through the one or more inverter cooling fluid passages and supply cooling fluid to a fluid reservoir.

[0132] EEE9 is an assembly as described in EEE8, in which a portion of a given inverter cooling fluid passage of one or more inverter cooling fluid passages is formed in the electronic device housing cover and a corresponding another portion of the inverter cooling fluid passage is formed in the backplate.

[0133] EEE10 is the assembly of any one of EEE1-9, further comprising a flow control valve configured to distribute cooling fluid between the cooled inner ring and the housing.

[0134] EEE11 is a hydraulic system including an actuator having a first chamber and a second chamber; a valve assembly configured to control fluid flow to and from the first and second chambers of the actuator; and an assembly including a main housing having an internal chamber; an electric motor disposed in the internal chamber of the main housing, the electric motor having a motor rotor; and a cooling inner ring disposed in the internal chamber of the main housing surrounding the electric motor, the cooling inner ring including one or more motor cooling fluid passages configured to receive cooling fluid from an external source of cooling fluid and to flow the cooling fluid around the electric motor to enable cooling of the electric motor, the main housing including: (i) a motor cooling fluid inlet port configured to receive the cooling fluid and supply the cooling fluid to the one or more motor cooling fluid passages; and (ii) a motor cooling fluid outlet configured to discharge the cooling fluid that has flowed through the one or more motor cooling fluid passages. a hydraulic pump positioned at least partially within a motor rotor of an electric motor within the main housing, the hydraulic pump configured to receive fluid from the inlet port and provide a fluid flow to an outlet port fluidly connected to the valve assembly, thereby providing a fluid flow to an actuator through the valve assembly; and a housing coupled to the main housing, the housing comprising: (i) an inverter board disposed therein; (ii) one or more inverter cooling fluid passages configured to allow cooling fluid from an external source to cool the inverter board; (iii) an inverter cooling fluid inlet port configured to receive cooling fluid and provide the cooling fluid to the one or more inverter cooling fluid passages; and (iv) an inverter cooling fluid outlet port configured to discharge the cooling fluid that has flowed through the one or more inverter cooling fluid passages.

[0135] EEE12 is the hydraulic system described in EEE11, wherein the hydraulic system further comprises a fluid reservoir, the inlet port of the hydraulic pump is fluidly connected to the fluid reservoir, whereby the hydraulic pump draws fluid from the fluid reservoir, the valve assembly is fluidly connected to the fluid reservoir to supply fluid discharged from the actuator to the fluid reservoir, and a portion of the fluid discharged from the actuator is branched off and supplied to the motor cooling fluid inlet port and the inverter cooling fluid inlet port, thereby the actuator constitutes an external source of cooling fluid.

[0136] EEE13 is a hydraulic system as described in EEE12, wherein the hydraulic system further comprises a valve disposed in a fluid line fluidly connecting the actuator and a fluid reservoir, the valve being configured to increase a pressure level upstream of the valve, and a portion of the fluid supplied to the motor cooling fluid inlet port and the inverter cooling fluid inlet port is branched off at a branch point disposed upstream of the valve.

[0137] EEE14 is the hydraulic system of any one of EEE11 to 13, wherein the assembly is configured to (i) receive fluid discharged from the actuator through the valve assembly at the inlet port and (ii) supply fluid to the actuator through the valve assembly via the outlet port, the hydraulic system further comprising an augmentation circuit fluidly connected to the valve assembly, the augmentation circuit configured to supply an augmented fluid flow and receive an excess fluid flow due to a difference between a fluid flow rate of the fluid supplied to or discharged from the first chamber and a fluid flow rate of the fluid supplied to or discharged from the second chamber, the augmentation circuit being fluidly connected to the motor cooling fluid inlet port and the inverter cooling fluid inlet port, the augmentation circuit forming an external source of cooling fluid for supplying cooling fluid to the motor cooling fluid inlet port and the inverter cooling fluid inlet port.

[0138] EEE15 is the hydraulic system as described in EEE14, further comprising a pressure reducing valve configured to receive cooling fluid from the boost circuit and supply cooling fluid at a reduced pressure level to the motor cooling fluid inlet port and the inverter cooling fluid inlet port.

[0139] EEE16 is a hydraulic system according to any one of EEE11 to 15, wherein the housing comprises an electronics housing coupled to the main housing and an electronics housing cover coupled to the electronics housing, whereby the housing is formed by the electronics housing cover and the electronics housing.

[0140] EEE17 is the hydraulic system of EEE16, wherein the inverter board is assembled to the electronics housing cover and one or more inverter cooling fluid passages are formed in the electronics housing cover.

[0141] EEE18 is the hydraulic system of EEE17, wherein the assembly further includes a backplate coupled to the electronics housing cover, the backplate having an inverter cooling fluid inlet port and an inverter cooling fluid outlet port, a portion of a given inverter cooling fluid passage of the one or more inverter cooling fluid passages being formed in the electronics housing cover and a corresponding other portion of the inverter cooling fluid passage being formed in the backplate.

[0142] EEE19 is the hydraulic system of any one of EEE11 to 18, further comprising a flow control valve configured to distribute cooling fluid between the cooled inner ring and the housing.

[0143] EEE20 is the hydraulic system of any one of EEE11 to 19, wherein the cooled inner ring comprises a plurality of arched ridges having one or more motor cooling fluid passages formed therebetween, a spiral motor cooling fluid passage formed as a looped recess surrounding the outer surface of the cooled inner ring, a zigzag motor cooling fluid passage formed as a recess surrounding the outer surface of the cooled inner ring, or a plurality of protrusions, each of which has a polygonal shape, thereby forming one or more motor cooling fluid passages between the plurality of protrusions, thereby enabling cooling fluid to be diffused through the one or more motor cooling fluid passages.

Claims

1. An assembly comprising: a main housing having an inner chamber; an electric motor disposed within the inner chamber of the main housing and comprising a motor rotor; a cooling inner ring disposed within the inner chamber of the main housing so as to surround the electric motor, the cooling inner ring receiving cooling fluid from an external source of cooling fluid and configured to allow the cooling fluid to flow so as to surround the electric motor and cool the electric motor, the cooling inner ring comprising one or more motor cooling fluid passages; a hydraulic pump at least partially positioned within the motor rotor of the electric motor within the main housing; a housing coupled to the main housing and comprising (i) an inverter board disposed therein and (ii) one or more inverter cooling fluid passages configured to allow cooling fluid from the external source to cool the inverter board; wherein the housing comprises (i) an inverter cooling fluid inlet port configured to receive cooling fluid from the external source and supply the cooling fluid to the one or more inverter cooling fluid passages formed in the housing, and (ii) an inverter cooling fluid outlet port configured to receive the cooling fluid that has flowed through the one or more inverter cooling fluid passages and supply the cooling fluid to a fluid reservoir. The assembly.

2. The assembly of claim 1, wherein the cooling inner ring comprises a plurality of arched ridges, whereby the one or more motor cooling fluid passages are formed between the plurality of arched ridges.

3. The assembly of claim 1, wherein the cooling inner ring comprises a helical or zigzag motor cooling fluid passage formed as a recess surrounding the outer surface of the cooling inner ring.

4. The assembly of claim 1, wherein the cooling inner ring comprises a plurality of protrusions, each of the plurality of protrusions having a polygonal shape, whereby the one or more motor cooling fluid passages are formed between the plurality of protrusions, thereby allowing the cooling fluid to be diffused through the one or more motor cooling fluid passages.

5. The main housing comprises: a motor cooling fluid inlet port configured to receive cooling fluid from the external source and supply the cooling fluid to the one or more motor cooling fluid passages of the cooling inner ring; A motor cooling fluid outlet port configured to supply the cooling fluid flowing through the one or more motor cooling fluid passages to a fluid reservoir The assembly according to claim 1, comprising

6. The housing An electronic device housing coupled to the main housing, An electronic equipment housing cover coupled to the electronic device housing And thereby, the housing is formed by the electronic equipment housing cover and the electronic device housing The assembly according to claim 1.

7. The inverter board is assembled to the electronic equipment housing cover, and the one or more inverter cooling fluid passages are formed in the electronic equipment housing cover. The assembly according to claim 6.

8. A back plate coupled to the electronic equipment housing cover, further comprising a back plate comprising the inverter cooling fluid inlet port and the inverter cooling fluid outlet port. The assembly according to claim 7.

9. A part of a predetermined inverter cooling fluid passage among the one or more inverter cooling fluid passages is formed in the electronic equipment housing cover, and another corresponding part of the inverter cooling fluid passage is formed in the back plate. The assembly according to claim 8.

10. The assembly according to claim 1, further comprising a flow control valve configured to distribute the cooling fluid between the cooling inner ring and the housing.

11. A hydraulic system An actuator having a first chamber and a second chamber, A valve assembly configured to control the fluid flow to and from the first chamber and the second chamber of the actuator, An assembly A main housing having an inner chamber, An electric motor disposed in the inner chamber of the main housing and comprising a motor rotor A cooling inner ring disposed to surround the electric motor in the inner chamber of the main housing, comprising one or more motor cooling fluid passages configured to receive cooling fluid from an external source of cooling fluid and flow the cooling fluid to surround the electric motor to enable cooling of the electric motor, wherein the main housing comprises: (i) a motor cooling fluid inlet port configured to receive cooling fluid and supply the cooling fluid to the one or more motor cooling fluid passages; and (ii) a motor cooling fluid outlet port configured to discharge the cooling fluid that has flowed through the one or more motor cooling fluid passages. A hydraulic pump at least partially positioned inside the motor rotor of the electric motor within the main housing, configured to receive fluid from an inlet port and supply a fluid flow to an outlet port fluidly connected to the valve assembly, thereby supplying a fluid flow to the actuator via the valve assembly. A housing coupled to the main housing, comprising: (i) an inverter board disposed therein; (ii) one or more inverter cooling fluid passages configured to enable the cooling fluid from the external source to cool the inverter board; (iii) an inverter cooling fluid inlet port configured to receive cooling fluid and supply the cooling fluid to the one or more inverter cooling fluid passages; and (iv) an inverter cooling fluid outlet port configured to discharge the cooling fluid that has flowed through the one or more inverter cooling fluid passages. An assembly comprising a fluid reservoir and comprising wherein the inlet port of the hydraulic pump is fluidly connected to the fluid reservoir, whereby the hydraulic pump withdraws fluid from the fluid reservoir, and the valve assembly is fluidly connected to the fluid reservoir to supply the fluid discharged from the actuator to the fluid reservoir, and a portion of the fluid discharged from the actuator branches off and is supplied to the motor cooling fluid inlet port and the inverter cooling fluid inlet port, such that the actuator constitutes the external source of cooling fluid. A hydraulic system.

12. The hydraulic system according to claim 11, further comprising a valve disposed in a fluid line fluidly connecting the actuator and the fluid reservoir, the valve being configured to increase the pressure level upstream of the valve, and a portion of the fluid supplied to the motor cooling fluid inlet port and the inverter cooling fluid inlet port being branched at a branch point disposed upstream of the valve.

13. A hydraulic system, an actuator having a first chamber and a second chamber, a valve assembly configured to control fluid flow to and from the first chamber and the second chamber of the actuator, an assembly, a main housing having an inner chamber, an electric motor disposed in the inner chamber of the main housing and comprising a motor rotor, a cooling inner ring disposed in the inner chamber of the main housing so as to surround the electric motor, the cooling inner ring being configured to receive cooling fluid from an external source of cooling fluid and to allow the cooling fluid to flow so as to surround the electric motor and cool the electric motor, the main housing comprising (i) a motor cooling fluid inlet port configured to receive cooling fluid and supply the cooling fluid to the one or more motor cooling fluid passages, and (ii) a motor cooling fluid outlet port configured to discharge the cooling fluid that has flowed through the one or more motor cooling fluid passages, the cooling inner ring; a hydraulic pump at least partially positioned inside the motor rotor of the electric motor within the main housing, the hydraulic pump being configured to receive fluid from an inlet port and supply a fluid flow to an outlet port fluidly connected to the valve assembly, thereby supplying a fluid flow to the actuator via the valve assembly. a housing coupled to the main housing and comprising: (i) an inverter board disposed therein; (ii) one or more inverter cooling fluid passages configured to enable a cooling fluid from the external supply source to cool the inverter board; (iii) an inverter cooling fluid inlet port configured to receive the cooling fluid and supply the cooling fluid to the one or more inverter cooling fluid passages; and (iv) an inverter cooling fluid outlet port configured to discharge the cooling fluid that has flowed through the one or more inverter cooling fluid passages an assembly configured to: (i) receive the fluid discharged from the actuator at the inlet port through the valve assembly; and (ii) supply the fluid to the actuator through the valve assembly via the outlet port a boost circuit fluidly connected to the valve assembly comprising The boost circuit is configured to supply a boost fluid flow and receive a surplus fluid flow due to a difference between a fluid flow rate of the fluid supplied to or discharged from the first chamber and a fluid flow rate of the fluid supplied to or discharged from the second chamber. The boost circuit is fluidly connected to the motor cooling fluid inlet port and the inverter cooling fluid inlet port and serves as the external supply source of the cooling fluid to supply the cooling fluid to the motor cooling fluid inlet port and the inverter cooling fluid inlet port. A hydraulic system

14. The hydraulic system according to claim 13, further comprising a pressure reducing valve configured to receive the cooling fluid from the boost circuit and supply the cooling fluid to the motor cooling fluid inlet port and the inverter cooling fluid inlet port at a reduced pressure level

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