US20200173430A1

US20200173430A1 - Battery-powered pump

Info

Publication number: US20200173430A1
Application number: US16/608,137
Authority: US
Inventors: Nathan Adam Hughes; Rustin Jay Dring
Original assignee: Actuant Corp
Current assignee: Enerpac Tool Group Corp
Priority date: 2017-04-28
Filing date: 2018-04-30
Publication date: 2020-06-04
Also published as: WO2018201141A1

Abstract

A self-contained pump system for supplying pressurized fluid to a remote actuator includes a handle portion adapted to be grasped by a user. The pump system also includes a brushless DC motor and a battery that has a nominal voltage of at least 60 V. The battery is operable to supply power to the motor. A 3-stage pump assembly is driven by the motor and operable to discharge hydraulic fluid that has a pressure and a flow rate.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of prior-filed, co-pending U.S. Provisional Patent Application No. 62/491,566, filed Apr. 28, 2017, the entire contents of which are incorporated by reference.

FIELD

The present invention generally relates to hydraulic pumps and, more particularly, to battery-powered pumps.

SUMMARY

Conventional battery-powered hydraulic pumps are driven by a motor having a typical power output of 0.5 to 0.75 horsepower (hp) which, due to the resulting lower flow output of the pump, are not suitable to demanding, high rate applications. These pump motors are powered by a battery pack having a nominal voltage of 18 volts (V) to 40 V.
Conventional AC-powered pumps are driven by direct drive AC induction motors or, more commonly, series-wound universal motors with gear reductions and have a typical power output of 1.75 to 2 hp. These pump motor tend to be loud, inefficient, brushed-type motors that draw a lot of current on a single phase AC power source.
In one independent aspect, a self-contained pump system for supplying pressurized fluid to a remote actuator includes a handle portion adapted to be grasped by a user; a motor, such as a brushless DC (BLDC) motor; a battery having a nominal voltage of at least 60 V operable to supply power to the motor; and a 3-stage pump assembly driven by the motor and operable to discharge hydraulic fluid having a pressure and flow rate.
In another independent aspect, a pump includes a housing; a motor supported by the housing; a pump assembly supported by the housing and driven by the motor to discharge hydraulic fluid; and a carrying handle assembly having a handle portion balanced relative to a center of gravity of the pump. In some constructions, the carrying handle assembly may include a protective bar extending along a side and over a top of the motor.
In yet another independent aspect, a self-contained pump system for supplying pressurized fluid to a remote actuator includes a motor, such as a brushless DC (BLDC) motor; a battery having a nominal voltage of at least 60 V operable to supply power to the motor; a 3-stage pump assembly driven by the motor and operable to discharge hydraulic fluid having a pressure and flow rate; a controller operable to control operation of the motor; and a remote control device in communication with the controller, the remote control device including a user-actuated switch operable to cause a signal to be communicated to the controller to operate the motor and, thereby, the pump assembly.
In a further independent aspect, a method of pumping hydraulic fluid may be provided. The method may generally include supplying power from a battery having a nominal voltage of at least 60 V to a motor, such as a brushless DC (BLDC) motor; with the motor, driving a 3-stage pump assembly; and, with the pump assembly, discharging hydraulic fluid having a pressure and flow rate. In some embodiments, the method may include actuating a remote switch to cause a signal to be communicated to a controller to operate the motor and, thereby, the pump assembly.
Independent features and independent advantages may become apparent upon review of the detailed description, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a pump system.

FIG. 2 is an end view of the pump system shown in FIG. 1.

FIG. 3 is a side view of the pump system shown in FIG. 1.

FIG. 4 is a perspective view of the pump system of FIG. 1, including a user pendant.

FIG. 5 is a partially exploded view of the pump system of FIG. 4, illustrating a battery and a removable cover.

FIG. 6 is an exploded view of the pump system of FIG. 4.

FIG. 7 is a cross-sectional view of the pump system of FIG. 1.

FIG. 8 is a schematic diagram of a circuit of the pump of FIG. 1.

FIG. 9 is a graph of flow, current and sound (dB) performance versus pressure for the pump shown in FIG. 1, with a fully-charged battery.

DETAILED DESCRIPTION

Before any independent embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other independent embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
Use of “including” and “comprising” and variations thereof as used herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Use of “consisting of” and variations thereof as used herein is meant to encompass only the items listed thereafter and equivalents thereof.
Also, the functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is “configured” in a certain way is configured in at least that way but may also be configured in ways that are not listed.
Furthermore, some embodiments described herein may include one or more electronic processors configured to perform the described functionality by executing instructions stored in non-transitory, computer-readable medium. Similarly, embodiments described herein may be implemented as non-transitory, computer-readable medium storing instructions executable by one or more electronic processors to perform the described functionality. As used in the present application, “non-transitory computer-readable medium” comprises all computer-readable media but does not consist of a transitory, propagating signal. Accordingly, non-transitory computer-readable medium may include, for example, a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a ROM (Read Only Memory), a RAM (Random Access Memory), register memory, a processor cache, or any combination thereof.
Many of the modules and logical structures described are capable of being implemented in software executed by a microprocessor or a similar device or of being implemented in hardware using a variety of components including, for example, application specific integrated circuits (“ASICs”). Terms like “controller” and “module” may include or refer to both hardware and/or software. Capitalized terms conform to common practices and help correlate the description with the coding examples, equations, and/or drawings. However, no specific meaning is implied or should be inferred simply due to the use of capitalization. Thus, the claims should not be limited to the specific examples or terminology or to any specific hardware or software implementation or combination of software or hardware.
FIGS. 1-7 illustrate a battery-powered hydraulic pump 10. In the illustrated embodiment, the pump 10 is a self-contained system in that a power source and fluid source are provided onboard, instead of as external components. In addition, the self-contained pump system is portable, in that the system includes features such as a handle to permit a user to easily move or transport the pump for use in remote work locations. In the illustrated construction, the pump 10 includes a high-voltage (e.g., having a nominal voltage of 60 V or greater) DC power unit and a 3-stage hydraulic pump assembly.
The pump 10 generally includes a housing 14 operable to support the pump 10 on a surface S, a power unit 18 including a motor 22 and a battery 26, and a pump assembly 30. In the illustrated construction, the motor 22 (FIGS. 6 and 7) includes a direct drive brushless DC (BLDC) motor (e.g., 1 hp, 82 V max). The power unit 18 may provide a peak torque of about 4.8 Newton meters (N m; about 42.75 inch pounds) at about 2600 revolutions per minute (rpm), 25 Amps (A) and about 1340 watts (W); its maximum torque may be limited to not exceed 20 A continuous or 25 A max.
As shown in FIG. 6-8, the battery 26 includes a battery pack with a housing 28 supporting a number of battery cells 29 to provide the desired discharge output (e.g., nominal voltage, current capacity, power, etc.). In the illustrated construction, the battery 26 includes rechargeable battery cells having a Lithium-based chemistry and electrically connected to provide high voltage (e.g., a nominal voltage of about 72 V and a maximum voltage of about 82 V) and capacity (e.g., 5.0 Amp hours (Ah)). In other constructions (not shown), the battery cells may have a different chemistry and be arranged to provide a different discharge output. The battery 26 may be removable for charging or use with other battery-powered equipment. The power unit 18 (FIG. 1) may be configured to charge the battery 26 in place.
Returning to FIGS. 1-3, the power unit 18 includes a power unit housing 34 supporting the motor 22 and providing a battery support portion 78 to electrically and mechanically connect the battery 26. In the illustrated construction, the support portion 78 includes a receptacle 82 to removably receive the battery 26 and is closed by a cover 38. The support portion 78 also includes a latch 86 that locks the battery 26 in place while the battery is received within the receptacle 82. A user may engage the latch 86 to unlock the battery 26 and remove the battery 26 from the battery support portion 78. A user may remove the cover 38 from the power unit housing 34 to expose the receptacle (FIG. 5). Removing the cover 38 allows a user to access and remove the battery 26 from the power unit housing 34. The battery 26 can be replaced with a new battery 26 or recharged and then reinserted into the receptacle. In other embodiments, the cover 38 may be pivotally coupled to the power unit housing 34 so that the cover 38 cannot be completely removed from the power unit housing 34.
The power unit 18 is connected to an adapter flange 42 to connect to the pump 30. In the illustrated construction, the flange 42 is relatively long to accommodate the motor drive shaft (not shown). In other constructions (not shown), the flange 42 may be shortened, with a shorter motor drive shaft, or eliminated altogether.
The flange 42 is connected to a reservoir 46, and the reservoir 46 is connected to and provides a source of hydraulic fluid for the pump assembly 30. As mentioned above, the pump assembly 30 includes three stages and is rated for 10,000 pounds per square inch (psi; 700 bar). With three stages, the pump assembly 30 can use a smaller, lower horsepower motor, while providing the same flow performance as existing AC-powered pumps with a larger, higher horsepower motor. The pump assembly 30 thus may contribute to preserving/increasing battery life compared to a situation in which the existing AC-powered pump was simply converted to be battery-powered.
A valve assembly 50 is supported on the housing 14 and connected in the hydraulic circuit (not shown) of the pump 10. In the illustrated construction, the valve assembly 50 is a 4-way, 3-position valve operable between a first “advance” position, a second “retract” position and a neutral position. The advance position allows hydraulic fluid to leave the pump 10 and travel to a remote actuator or tool (e.g., a hydraulic jack, a power tool, etc.—not shown) via a conduit or tubing (not shown). The retract position allows hydraulic fluid to travel from the tool and return to the reservoir 46. The valve 50 is manually operated by a lever 52.
A carrying handle assembly 54 is connected to the housing 14. The assembly 54 includes a handle portion 58 positioned and configured to provide an ergonomic carrying position for the pump 10 (e.g., the center of gravity balanced at the carrying point and with a user's hand parallel to the body). The new carrying handle assembly 54 allows for single-handed carrying in a more ergonomic manner than conventional carrying methods of comparably-sized pumps.
The assembly 54 also includes a roll bar portion 62 constructed and arranged to protect components of the pump 10 (e.g., from impacts). The roll bar portion 62 extends over and around the power unit 18, while allowing unimpeded access to the battery compartment, pump controls, etc.
As shown in FIG. 8, the pump 10 includes a controller 66 operable to, among other things, configure and control operation of the pump 10 and/or of its components. The controller 66 includes a processing unit (e.g., a microprocessor, a microcontroller, or another suitable programmable device), non-transitory computer-readable media, and an input/output interface. The processing unit, the media, and the input/output interface are connected by one or more control and/or data buses. The computer-readable media stores program instructions and data. The processing unit is configured to retrieve instructions from the media and execute the instructions to perform the control processes and methods described herein.
The input/output interface transmits data from the controller 66 to external systems, networks, and/or devices and receives data from external systems, networks, and/or devices. The input/output interface stores data received from external sources to the media and/or provides the data to the processing unit.
A control device (see FIGS. 4 and 8; e.g., a user-held remote pendant 70) communicates with the controller 66 to provide user inputs to control operation of the pump 10. In the illustrated construction, the pendant 70 includes a switch 74, providing a simple interface for the user while facilitating maximum runtime of the battery 26. When the switch 74 is depressed, the controller 66 turns on and runs the motor 22 and operates the pump assembly 30 until the switch 74 is released. Depressing the switch 74 drives the pump assembly 30 to pump fluid in a direction set by the valve assembly 50 (i.e., advance or retract). The switch 74 does not control the position of the valve assembly 50.
As shown in FIG. 8, the motor 22, the battery 26 and the pendant 70 communicate with the controller 66. The controller 66 receives information from and transmits information to the components of the pump 10 and controls operation of the pump 10. As mentioned above, depressing the switch 74 causes a signal to be communicated from the pendant 70 to the controller 66 to operate the motor 22 and, thereby, the pump assembly 30. The controller 66 also receives information regarding the status/characteristics of the components (e.g., the voltage, temperature of the battery 26, the load on the motor 22, etc.) and, based on this information, controls operation of the pump 10.
The controller 66 may be programmed to achieve different speeds and target peak efficiency with algorithms for constant horsepower flow curves. Additional functions, such as, for example, pressure control with a sensor or based on instantaneous motor current and speed, may be added that utilize the “smart control” of the controller 66.
The illustrated pump 10 may be used in demanding applications requiring high flow rates. One such application is post-tensioning of a tendon (not shown) positioned in a concrete structure (not shown). In such applications, the pump 10 may be connected and supply pressurized hydraulic fluid to a cylinder assembly (not shown; e.g., single-acting or double-acting) operable to apply tension to the tendon.
FIG. 9 illustrates the performance of the pump 10 according to some embodiments. For example, performance variables include flow rate (in cubic inches per minute (CIM)), current (in amperes (A)), and sound (in decibels (dB)). Each of the performance variables are measured at different pressures which may correspond to different stages of the pump (i.e., a first stage from 0-1100 psi, a second stage from 1100-4000 psi, and a third stage from 4000-10000 psi). The flow rate has a generally shallow decreasing slope in the first, second, and third stages and a much steeper decreasing slope while transitioning between stages. In the illustrated embodiment, the pump 10 has a max flow rate of approximately 360 CIM in the first stage, 110 CIM in the second stage, and 35 CIM in the third stage. The current increases during the first, second, and third stages, and decreases during the transition between the stages. The sound level of the pump remains generally consistent through the three stages, slightly increasing from the first stage to the third stage. In the illustrated embodiment, the pump 10 outputs approximately 83 dB of sound around the first and second stages, and outputs approximately 87 dB of sound around the second and third stages.
In the illustrated construction, with a 1 hp, 82V max, BLDC motor and a 3 stage hydraulic pump assembly, the pump 10 delivers the performance of a larger 1.75 to 2 hp corded AC-powered pump without the limitations of AC corded power. The battery power allows for improved portability in remote applications without readily available AC line voltage and without requiring a generator.
The battery 26, with a 72 V nominal voltage (82 V max) and a 5.0 Ah capacity leads to a system with about 360 W-h of available energy (72 V*5.0 Ah). In comparison, a conventional battery-powered pump powered by a 28 V to 40 V battery may provide only about 129 to 200 W-h of available energy. Users in high demand applications may need increased energy and higher performance which can be provided by the pump 10.
The 3-stage pump assembly 30 delivers the same speed as traditional 2-stage AC-powered pumps. This allows for a smaller motor design, which yields more cycles per charge in the battery-powered pump 10. The direct drive BLDC motor 22 has higher efficiency than corded motors, which also leads to improved battery life and reduced heat generation.
Certain embodiments have been described in detail. Many modifications and variations to the embodiments described will be apparent to a person of ordinary skill in the art. Accordingly, the disclosure is not limited to the embodiments described.
One or more independent features and independent advantages may be set forth in the claims.

Claims

What is claimed is:

1. A self-contained pump system for supplying pressurized fluid to a remote actuator, the pump system comprising:

a handle portion adapted to be grasped by a user;

a brushless DC motor;

a battery having a nominal voltage of at least 60 V and operable to supply power to the motor; and

a 3-stage pump assembly driven by the motor and operable to discharge hydraulic fluid having a pressure and a flow rate.

2. The pump system of claim 1, further comprising,

a controller operable to control at least one of the motor and the pump assembly; and

a control device in communication with the controller, the control device operable to receive a user input.

3. The pump system of claim 1, wherein the handle portion is disposed above the pump assembly and balanced relative to a center of gravity of the pump.

4. The pump system of claim 1, further comprising a roll bar spaced apart from the pump assembly.

5. The pump system of claim 1, further comprising a housing including a cavity and a cover, the cover movable between a first position in which the cavity is accessible and a second position in which the cavity is covered.

6. The pump system of claim 1, wherein a sound output of the pump assembly is less than 100 dB.

7. The pump system of claim 1, further comprising a valve having a lever movable between a first position and a second position, the valve configured to direct fluid flow in a first direction when the lever is in the first position and configured to direct fluid flow in a second direction when the lever is in the second position.

8. The pump system of claim 1, further comprising a reservoir in fluid communication with the pump assembly.

9. The pump system of claim 1, wherein the battery has a nominal voltage of about 72 V.

10. A self-contained pump system for supplying pressurized fluid to a remote actuator, the pump system comprising:

a motor;

a battery having a nominal voltage of at least 60 V operable to supply power to the motor;

a pump assembly driven by the motor and operable to discharge hydraulic fluid having a pressure and flow rate;

a controller operable to control operation of the motor; and

a remote control device in communication with the controller, the remote control device including a user-actuated switch operable to cause a signal to be communicated to the controller to operate the motor and, thereby, the pump assembly.

11. The pump system of claim 10, further comprising a handle portion adapted to be grasped by a user, the handle portion balanced relative to a center of gravity of the pump assembly.

12. The pump system of claim 10, further comprising a housing including a cavity and a cover, the cover movable between a first position in which the cavity is accessible and a second position in which the cavity is covered.

13. The pump system of claim 10, further comprising a valve having a lever movable independently of the remote control device between a first position and a second position, the valve configured to direct fluid flow in a first direction when the lever is in the first position and configured to direct fluid flow in a second direction when the lever is in the second position.

14. The pump system of claim 10, further comprising a bar extending along a side and over a top of the motor.

15. The pump system of claim 10, wherein the motor is a brushless DC motor and the pump assembly is a 3-stage pump assembly.

16. The pump system of claim 10, further comprising a reservoir in fluid communication with the pump assembly.

17. The pump system of claim 10, wherein the battery has a nominal voltage of about 72 V.

18. A method of pumping hydraulic fluid, the method comprising:

supplying power from a battery having a nominal voltage of at least 60 V to a brushless DC motor;

with the motor, driving a 3-stage pump assembly; and

with the pump assembly, discharging hydraulic fluid having a pressure and flow rate.

19. The method of claim 18 further comprising, actuating a remote switch to cause a signal to be communicated to a controller to operate the motor and, thereby, the pump assembly.

20. The method of claim 18 further comprising, actuating a lever coupled to a valve of the pump assembly to one of a first position configured to direct fluid flow in a first direction and second position configured to direct fluid flow in a second direction.