Hydraulic tool with external rotor electric motor

Abstract

A hydraulic tool comprises an external rotor electric motor with a rotor and a stator, a hydraulic pump, and a gearbox coupled between the electric motor and the hydraulic pump. In one example, the stator is at least partially enclosed within the rotor. In another example, the electric motor drives the hydraulic pump via the gearbox to pressurize the hydraulic fluid within the hydraulic tool.

Description

Cross-reference to related registrations This application claims the benefit of the preliminary US patent application No. 63 / 487,852, filed on March 1, 2023, which is hereby incorporated by reference in its entirety. background Hydraulic power tools such as hydraulic pumps, presses, crimping pliers, cutting tools, lifting cylinders, nut splitters, etc., are frequently used for machining workpieces. Typically, in these tools, a hydraulic pump pressurizes hydraulic fluid by moving a hydraulic piston. In some cases, the pump is driven by an electric motor. However, typical electric motors increase the weight and overall dimensions of the tool, which may be undesirable for the end user. Summary Against this background, there is a desire for smaller and lighter hydraulic crimping pliers and cutting tools. Some embodiments of the disclosure provide a hydraulic tool comprising an electric motor with an external rotor, a stator, a hydraulic pump, and a gearbox coupled between the electric motor and the hydraulic pump. The electric motor drives the hydraulic pump via the external rotor to pressurize the hydraulic fluid within the hydraulic tool. The stator may be at least partially contained within the external rotor. In one example, the stator comprises a stator mount and a stator core held by the stator mount, the core defining a central bore. The rotor comprises a rotor shaft arranged within the central bore of the stator core. In another example, the rotor circumferentially surrounds the stator. The motor further comprises one or more sets of magnets arranged circumferentially around the rotor. In one example, the magnet sets each comprise a pair of magnets of the same polarity. In another example, the rotor is arranged circumferentially around the stator and radially outside the stator. The motor further includes one or more sets of magnets arranged circumferentially around the rotor, each set comprising a pair of magnets of the same polarity, such that the number of magnets inside the rotor is twice the number of magnet sets inside the rotor. In yet another example, the tool comprises a hydraulic pump, a gearbox positioned between the electric motor and the hydraulic pump, and a mounting bracket coupled to the electric motor. The mounting bracket includes a projection that defines a through-channel. A pin is inserted through the through-channel and a section of the gearbox to couple the electric motor to the gearbox. Brief description of the drawings The accompanying drawings, which are included in and form part of this description, represent embodiments of the disclosure and, together with the description, serve to explain the principles of the embodiments of the disclosure. Fig. 1 is a perspective view of an example of a hydraulic tool with an external rotor electric motor according to aspects of the present disclosure. Fig. 2 is a cross-sectional view of the hydraulic tool of Fig. 1. Fig. 3 is a side view of a drive train assembly of the hydraulic tool of Fig. 1. Fig. 4 is a perspective front view of an external rotor electric motor of the drive train assembly of Fig. 3. Fig. 5 is a perspective rear view of the external rotor electric motor of the drive train assembly of Fig. 4. Fig. 6 is a cross-sectional view of the external rotor electric motor of Fig. 4. Fig. 7 is an exploded view of the external rotor electric motor of Fig. 4 from the front.Figure 8 is a rear exploded view of the external rotor electric motor of Figure 4. Figure 9 is an exploded view of a stator assembly of the external rotor electric motor of Figure 4. Figure 10 is an exploded view of a rotor assembly of the external rotor electric motor of Figure 4. Figure 11 is an exploded view of another example of a drive train assembly of the hydraulic tool of Figure 1. Figure 12 is a perspective view of another example of a motor for use with the hydraulic tool of Figure 1. Figure 13 is an exploded view of another example of a drive train assembly of the hydraulic tool of Figure 1. Figure 14 is a perspective view of the drive train assembly of Figure 13. Figure 15 is a first perspective view of a rotor of the motor of Figure 12. Fig. 16 is a second perspective view of the runner of Fig. 15. Fig. 17 is a partial cross-sectional view of the runner of Fig. 15. Detailed description The following explanation is intended to enable a person skilled in the art to create and use embodiments of the disclosure. Various modifications of the embodiments shown are readily apparent to those skilled in the art, and the general principles and applications contained herein can be applied without deviating from the embodiments of the disclosure. Therefore, embodiments of the disclosure are not limited to those shown, but should be considered to the greatest extent possible in accordance with the principles and features disclosed herein. The following detailed description should be read with reference to the figures, in which identical elements in different figures are designated with the same reference numerals. The figures, which are not necessarily to scale, show selected embodiments and are not intended to limit the scope of the embodiments of the disclosure. Those skilled in the art will recognize that the examples presented here offer many useful alternatives and fall within the scope of the embodiments of the disclosure. Before any embodiments of the disclosure are explained in detail, it should be understood that the disclosure, in its application, is not limited to the design details and arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure may have other embodiments and be practiced or implemented in various ways. It should also be understood that the language and terminology used herein serve for descriptive purposes and should not be considered limiting. The use of "including," "comprising," or "having" and variations thereof is intended to encompass the elements listed thereafter and their equivalents, as well as additional elements.Unless otherwise specified or limited, the terms "mounted," "connected," "held," and "coupled," and their variations, are used broadly and include both direct and indirect mounting, connections, mounting brackets, and couplings. "Connected" and "coupled" are also not limited to physical or mechanical connections or couplings. As briefly described above, hydraulic tools can be used to process workpieces such as cables, rods, wires, pipes, reinforcing bars, or other components (e.g., crimping, cutting, lifting, pressing, pumping, etc.). A hydraulic tool might, for example, comprise a hydraulic cylinder and punch assembly, with the punch configured to extend and retract within the cylinder. The movement of the punch generates a corresponding movement in the jaws or other tools connected to the punch to perform a task (crimping, cutting, pressing, lifting, etc.). Hydraulic tools also typically include a hydraulic pump driven by an electric motor. In one embodiment, the motor is an external rotor electric motor. The hydraulic pump pressurizes hydraulic fluid in the hydraulic system to generate the movement of the punch. Some embodiments of the disclosure provide for an external rotor electric motor connected to the pump via a gearbox. In other examples, the external rotor electric motor can be directly connected to the pump (e.g., in a direct drive arrangement without a gearbox). The external rotor electric motor is capable of generating considerable torque to drive the pump, allowing greater force to be applied to the workpiece via the crimping / cutting device. Furthermore, the external rotor electric motor enables the manufacture of smaller and lighter tools, which is advantageous for the user. Embodiments of the disclosure can offer advantages over conventional internal rotor electric motors. Examples of improvements include increasing the torque generated by the motor or reducing the overall size and weight of the hydraulic tool. Figures 1 and 2 show an example of a hydraulic tool 10. In one example, the hydraulic tool 10 is a hydraulic crimping / cutting tool. The tool 10 comprises a head 12 connected to a body 13. In one example, as shown in Figure 2, the head 12 defines a substantially C-shaped opening 14 configured to receive a component, such as a wire, cable, rod, tube, or other component, to be crimped or cut by the tool 10. As shown in Figure 2, a removable die 15 is mounted on a hydraulic ram 16 within the opening 14. The die 15 can be removed or replaced depending on the desired function of the tool 10. For example, a crimping die can be used when crimping is desired, and a cutting die can be used when cutting is desired.The die 15 is actuated by the movement of the hydraulic ram 16. In one example, the hydraulic ram 16 is actuated by hydraulic force or pressure supplied via one or more hydraulic components 17 of the tool 10. In another example, a button 11 located on the body 13 of the tool 10 can be operated by the user to move the ram 16 forward or backward. The hydraulic components 17 of the tool 10 can include a hydraulic pump that pressurizes hydraulic fluid to actuate the ram 16. In one example, the hydraulic pump can be connected to an electric motor 18 via a gearbox 19. The gearbox 19 can be configured to modify the power of the electric motor 18 to increase the torque or speed generated by the electric motor 18. In another example, the hydraulic pump can be connected directly to the electric motor 18 without the gearbox 19 (e.g., via a direct-drive arrangement). In one example, the electric motor is a brushless external rotor electric motor. In another example, the motor 18 is powered by a removable battery pack coupled to the motor (e.g., in a cordless design).In another example, the tool 10 can include a power cable for electrically connecting the motor 18 to an alternating current (AC) source (e.g., in a corded version). Furthermore, it is evident that the external rotor electric motor can be used with a variety of hydraulic tools of different sizes, shapes, and functions. For example, the external rotor electric motor can be used with hydraulic pumps, hydraulic presses, hydraulic crimping pliers, hydraulic cutting tools, hydraulic lifting cylinders, hydraulic nut splitters, or any other known hydraulic tool. Figure 3 shows an example of a drive train assembly 21 for the hydraulic tool 10. The drive train assembly 21 can include the electric motor 18 and the gearbox 19. In one example, the drive train assembly 21 can include the electric motor 18, the gearbox 19, and an optional adapter plate 25. The adapter plate 25 can be used to connect the motor 18 to the gearbox 19. In other examples, the drive train assembly 21 can omit the adapter plate 25, and instead, the motor 18 can be mounted directly on the gearbox 19. As can be seen in Figure 3, the drive train assembly 21 can have an overall length 23. In one example, the length 23 of the drive train assembly 21 can be less than 90 mm. In another example, the length 23 of the drive train assembly 21 can be between 80 and 90 mm.In one example, the total length 23 of the drive train assembly 21, including the external rotor electric motor 18, is less than the length of the drive train assembly with an internal rotor electric motor. Referring to Figures 4-10, the motor 18 is a brushless DC motor (“BLDC”) with a stator 20 and a rotor 22, which is rotatable about an axis 24 relative to the stator 20 (see, for example, Figure 7). In other words, the rotor 22 rotates about the axis 24, while the stator 20 is fixed (i.e., stationary, non-rotatable) with respect to the axis 24 and the rotor 22. The BLDC electric motor 18 is an external rotor BLDC electric motor, with the rotor 22 generally surrounding the stator 20 circumferentially. Thus, the rotor 22 is an external rotor 22, and the stator 20 is an internal stator 20, which is at least partially contained within the external rotor 22 and generally circumferentially surrounded by it. As shown in Fig. 9, the stator 20 comprises a stator support 26, a stator core assembly 28 rigidly supported by the stator support 26, and a plurality of wires or stator windings defining a plurality of coils 32. In one example, the stator 20 comprises 12 slots (e.g., coils 32). In other examples, the stator 20 may comprise more or fewer slots (e.g., coils 32). The stator core assembly 28 comprises a stator core 34 formed from a stack of sheet metal laminations and an insulator 36 integrally formed with the core 34. The stator core 34 comprises a central core back 38 and a plurality of teeth 40 projecting outward from the core back 38. The coils 32 are arranged around (surrounding) the teeth 40 and insulated from the teeth 40 by the insulator 36. The core back 38 defines a core center bore 42 that extends longitudinally through the stator core assembly 28.The stator support 26 comprises an elongated stator support section 44 and a motor support section 46 at one end of the stator support section 44. The stator support section 44 is sufficiently tubular and supports the stator core assembly 28. More precisely, the core center bore 42 of the stator core 34 accommodates the stator support section 44. Thus, the stator core assembly 28 is rigidly mounted around the stator support section 44. In other words, the stator core assembly 28 is arranged circumferentially around the stator support section 44. In some examples, the stator core 34 can accommodate the stator support section 44 by an interference fit or interference fit. In other examples, the stator support section 44 can be fixed to the stator core 34 by a forming process. The stator support 26 further comprises a hollow mounting center bore 48 that extends longitudinally through the stator support 26, including through both the stator support section 44 and the motor support section 46. As shown in Fig. 10, the rotor 22 comprises a central rotor shaft 50, a rotor frame 52, a tubular rotor body 54, and a plurality of permanent magnets 56. The permanent magnets 56 can, for example, comprise magnets of different polarities. For example, the magnets can comprise one or more magnets of a first polarity 61 and one or more magnets of a second polarity 63. The magnets can be arranged alternately around the rotor 22. For example, the magnets 56 can alternate between magnets of a first polarity 61 and magnets of a second polarity 63. The rotor frame 52 can be annular and include a central section 57A configured to receive the rotor shaft 50. An outer circumferential section 57B of the rotor frame 52 can be fixed to the rotor body 54. The rotor frame 52 fixes the rotor body 54 to the rotor shaft 50 for joint rotation. In other words, the rotor frame 52 secures the rotor body 54 to the rotor shaft 50 to allow rotation of the rotor shaft 50 and to initiate a corresponding rotation of the rotor body 52. A plurality of radially and axially extending blades 57C extend between and connect the central section 57A and the outer circumferential section 57B. A plurality of airflow openings 57D are defined between each pair of adjacent blades 57C. The blades 57C act as fans, generating an airflow that passes through the airflow openings to cool the electric motor 18. In some examples, the rotor frame 52 may be made of metal or a metal alloy (e.g., zinc or steel). In other embodiments, the frame 52 may be formed from a resin material. The rotor body 54 can be tubular and have a radially inner surface 58 that defines a central cavity 60. The permanent magnets 56 can be rigidly mounted on the radially inner surface 58 of the rotor body 54. In one example, the motor 18 can be a ten-pole motor with ten permanent magnets 56. In other examples, the motor can contain more or fewer than ten permanent magnets. The number of magnets 56 can be distributed equally between magnets of the first polarity 61 and the second polarity 63. As shown in Fig. 6, the rotor body 54 is located radially outside the stator 20 and surrounds sections of the stator 20, including the stator core 28, the coils 32, and sections of the stator support 26. Sections of the stator 20, including all or substantially most of the stator core 28, are received in the central cavity 60 of the rotor body 54. The rotor shaft 50 is rotatably mounted relative to the stator 20 by one or more bearings, including a first bearing 62 and a second bearing 64. Thus, the rotor 22 (i.e., including the rotor shaft 50, the rotor frame 52, the rotor body 54, and the magnets 56) rotates relative to the stator 20. The rotor shaft 50 passes centrally through the stator 20, through both the core center bore 42 and the mounting center bore 48. In one example, the motor 18 can include a ring-shaped printed circuit board assembly (PCBA) 66 fixed to the insulator 36 of the stator 20 (see, for example, Fig. 9). The PCBA 66 can include at least one position sensor. For example, the PCBA can include a Hall-effect sensor for detecting the position of the permanent magnets 56 of the rotor 22. Additionally or alternatively, the PCBA 66 can include a variety of circuits (e.g., field-effect transistors (FETs)) that can be actuated to electrically commutate the motor 18. In some examples, the motor 18 may not include the PCBA 66 (e.g., in sensorless motor drive arrangements). The rotor shaft 50 has an output end 70 that projects beyond the motor support section 46 of the stator mount 26. The output end 70 can be rigidly coupled to an output element (e.g., a gear, a pump, etc.). For example, the output end 70 can be coupled to the hydraulic components 17 to pressurize hydraulic fluid used to actuate the ram 16. In other examples, the output end 70 can be coupled to the hydraulic components 17 via the gearbox 19. The output end 70 enables the transmission of the torque or motion generated by the motor 18 to other components of the tool 10. During operation, the coils 32 are energized (e.g., via the battery pack) to cause rotation of the rotor 22 relative to the stator 20.The alternating polarity within the coils, in conjunction with the alternating polarity of the magnets 56, maintains the rotation of the rotor 22 as long as the motor is powered (e.g., via the battery pack). The rotor shaft 50, the frame 52, and the rotor body 54 rotate together relative to the stationary stator 20 and the PCBA 66. The design of the external rotor electric motor allows for a greater number of poles (i.e., magnets) and a greater number of slots (i.e., coils) within the electric motor, enabling the motor to generate a higher overall torque. The first bearing 62 is received in a first bearing pocket 74 defined in the motor support section 46 of the stator bracket 26. An outer ring of the first bearing 62 is held by the motor support section 46 within the first bearing pocket 74, and an inner ring of the first bearing 62 supports the rotor shaft 50 in a rotatable manner. The inner ring of the first bearing 62 allows the rotor shaft 50 to rotate freely without transmitting the corresponding rotation to the stator bracket 26. The second bearing 64 is received in a second bearing pocket 76 defined in the stator core 34. The second bearing pocket 76 is defined at an axial end of the stator core 34 and is adjacent to the core's central bore 42. In one example, both the second bearing pocket 76 and the core's central bore 42 have circular cross-sections. In the illustrated embodiment, the second bearing pocket 76 has a larger diameter than the core's central bore and forms a shoulder or step 78. An outer ring of the second bearing 64 is held by the stator core 34 within the second bearing pocket 76. An inner ring of the second bearing 64 supports the rotor shaft 50 in a rotatable manner. The outer ring of the second bearing 64 rests against the step 78 and the rotor frame 52, so that the step 78 and the rotor frame 52 prevent axial movement of the second bearing 64.The inner ring of the second bearing 64 allows the free rotation of the rotor shaft 50 without transferring the corresponding rotation to the stator core 34. As shown in Fig. 9, the motor support section 46 comprises a pair of radially projecting tabs 80 arranged opposite each other around the axis 24, and a pair of corresponding screw bosses 82 formed within the tabs 80. The screw bosses 82 are configured to accept one or more fasteners (e.g., screws, nuts, bolts, or other fasteners) to secure the stator mount 26 to a motor mount configured to support the motor 18. As shown in Fig. 11, the motor 18 can also include a modular adapter plate 84, which is removably coupled to the motor support section 46 of the stator mount 26 (e.g., via one or more threaded fixings). The adapter plate 84 is further configured to be removably connected to a stationary component. The adapter plate 84 can, for example, be coupled to a gearbox 86. The adapter plate 84 comprises a base plate 87 and a pair of annular outer bayonet couplings 88 formed on the circumference of the base plate 87 and generally opposite each other with respect to the axis 24. The base plate 87 defines a central opening 90 that allows the rotor shaft 50 to pass through the base plate 87. The base plate 87 also defines a pair of mounting holes 92 that correspond to (e.g., are aligned with) the two screw bosses 82 formed on the stator support 26.The outer bayonet couplings 88 define slots 94 configured to receive a pair of outwardly projecting tabs 96 extending from the gearbox 86. In other words, the slots 94 of the bayonet couplings 88 receive the tabs 96 of the gearbox 86 to secure the adapter plate 84 to the gearbox 86 and couple the stator carrier 26 to the gearbox 86. Thus, the motor 18 can be secured to the gearbox 86 via the adapter plate 84 instead of being directly connected to the gearbox 86. Figures 12-14 show another example of a motor 1200 with a mounting bracket 1210 to enable a pin connection between the motor 1200 (e.g., via the mounting bracket 1210) and a gearbox 1305. It is understood that the use of the mounting bracket 1210 allows a direct connection between the motor 1200 and the gearbox 1305 without the need for an adapter plate, thereby reducing the overall size and weight of the tool. In one example, the mounting bracket 1210 can include a pair of opposing projections 1215 integrated into the mounting bracket 1210. Each projection 1215 can include a through-channel 1220 extending through the projections 1215. In another example, the mounting bracket 1210 can be partially inserted into the gearbox 1305 such that the through-channels 1220 of the projections 1215 align with the openings 1315 of one or more mounting tabs 1310 integrated into the gearbox 1305. To secure the motor 1200 to the gearbox 1305, one or more pins 1320 can be arranged through both the openings 1315 and the through-channels 1220. In one example, the pins 1320 can comprise an essentially tubular body with a first end 1325 whose size (e.g. diameter) is smaller than a second end 1330 of the pins 1320. In an exemplary application, the motor 1200, including the mounting bracket 1210, can be partially inserted into the gearbox 1305 and aligned so that the through-channels 1220 are aligned with the openings 1315 of the gearbox 1305. The first end 1325 of the pins 1320 can then be inserted into the openings 1315 and a force applied to the pins 1320 so that the body of the pins 1320 passes through the through-channels 1220 until the second end 1330 of the pins 1320 rests against the mounting tabs 1310 of the gearbox 1305. In other words: The size (e.g. the diameter) of the second end 1330 of the pins 1320 can be dimensioned such that the insertion of the second end 1330 of the pins 1320 into or through the openings 1315 or the passage channels 1220 is prevented. In another example, the motor 1200 can have a motor shaft 1225 with a patterned or toothed surface for further attachment to the gearbox 1305, thereby reducing the overall length of the motor 1200 and the gearbox 1305. In another example, the gearbox 1305 can have a drive gear that can mesh with or be pressed onto the corresponding motor shaft 1225 to connect the gearbox 1305 and the motor 1200. It is understood that meshing the motor shaft 1225 with the gearbox 1305 can reduce the need for additional connecting components, which can further reduce the overall length of the motor 1200 and the gearbox 1305. Figures 15-17 show another example of a runner 1500 that can be used with the tool 10 of Figure 1 (e.g., as an alternative configuration of the runner 22). As can be seen, the runner 1500 has a number of components that are identical to and function similarly to the previously shown and described examples. For the sake of brevity, these common features will not be described again in detail below. Rather, the previous discussion of generally named or numbered features also applies to example configurations of the runner 1500, unless otherwise stated. In one example, the runner 1500 comprises one or more sets of magnets arranged around its circumference. For instance, the runner 1500 may comprise one or more first sets of magnets 1502, each containing one or more magnets (e.g., a pair of magnets) of a first polarity, and one or more second sets of magnets 1505, each containing one or more magnets (e.g., a pair of magnets) of a second, different polarity. In another example, the magnets within a set of magnets (e.g., the first set of magnets 1502 or the second set of magnets 1505) may each be magnets of the same polarity. For instance, the first set of magnets 1502 may comprise a first magnet 1520 of a first polarity and a second magnet 1525 of the same polarity (e.g., the first polarity). Accordingly, the second set of magnets 1505 can provide a first magnet 1510 with a second polarity and a second magnet 1515 with the same polarity (e.g.the second polarity), which differs from the first polarity of the first set of magnets 1502. Furthermore, the magnets can be flat magnets, arc magnets, or a combination of flat and arc magnets. In a specific example, the motor 1200 can include the rotor 1500, so that the motor 1200 can be a ten-pole (10) motor with twenty (20) permanent magnets. In other words, the motor 1200 can include ten (10) magnet sets (e.g., five (5) first magnet sets 1502 and five (5) second magnet sets 1505), each containing a pair of permanent magnets (e.g., magnets 1510 / 1515 or magnets 1520 / 1525). In one example, the number of magnet sets and magnets can be distributed equally between the first and second polarities. As shown in Figures 16 and 17, the rotor 1500 can include a frame 1615, which may be in the form of a molded frame (e.g., overmolded from a polymer material). In one example, the frame 1615 may be shaped to include an integrated fan 1605 for cooling the motor 1200. In another example, the frame 1615 may include an integrated bearing retainer 1610 for holding the second bearing 64. In other words, the frame 1615 may be shaped as a single, unitary frame including the fan 1605 and the bearing retainer 1610. In one example, the frame 1615 can further include one or more magnet retaining ribs 1705. The retaining ribs 1705 can interact with a divider 1710 further molded into the frame 1615 to hold the magnets (e.g., magnets 1510, 1515, 1520, 1525) of the magnet sets (e.g., magnet sets 1502, 1505). For example, the retaining ribs 1705 and the divider 1710 define slots 1715 that circumferentially surround the runner 1500. In another example, the slots 1715 can receive and hold a magnet (e.g., a magnet 1510, 1515, 1520, 1525) between a retaining rib 1705 and a divider 1710. Furthermore, the space between the sets of retaining ribs 1705 can define the magnet sets (e.g., magnet sets 1502, 1505). In one example, the slots 1715 can be configured to receive and hold both arc and flat magnets via the retaining ribs 1705 and the divider 1710. In some implementations, devices or systems disclosed herein may be used, manufactured, or installed using methods that embody aspects of the disclosure. Accordingly, any description herein of specific features, capabilities, or uses of a device or system is intended to include, in principle, the disclosure of a method for using such devices for the intended purposes, a method for otherwise implementing such capabilities, a method for manufacturing relevant components of such a device or system (or the device or system as a whole), and a method for installing disclosed (or otherwise known) components to support such purposes or capabilities.Likewise, unless otherwise specified or limited, the discussion contained herein of a method for manufacturing or using a particular device or system, including the installation of the device or system, shall in principle include the disclosure of the features used and capabilities implemented by that device or system as embodiments of the disclosure. Unless otherwise restricted or defined, "or" herein denotes a non-exclusive list of components or operations that can exist in any combination, rather than an exclusive list of components that can exist only as alternatives to one another. For example, a list of "A, B, or C" denotes the following options: A; B; C; A and B; A and C; B and C; and A, B, and C. Accordingly, the term "or," as used here, is intended to indicate exclusive alternatives only when preceded by exclusive terms such as "either," "one of," "only one of," or "exactly one of." For example, a list of "one of A, B, or C" indicates the following options: A, but not B and C; B, but not A and C; and C, but not A and B.A list preceded by "one or more" (and variations thereof) and containing "or" to separate the listed items indicates options for any one or more, or all, of the listed items. For example, the expressions "one or more of A, B, or C" and "at least one of A, B, or C" indicate the following options: one or more A; one or more B; one or more C; one or more A and one or more B; one or more B and one or more C; one or more A and one or more C; and one or more of A, one or more of B, and one or more of C. Similarly, a list preceded by "a multitude of" (and variations thereof) and separating the listed items with "or" indicates options for multiple instances of some or all of the listed items.For example, the expressions “a plurality of A, B or C” and “two or more of A, B or C” indicate options of: A and B; B and C; A and C; and A, B and C. Unless otherwise defined or limited, directional references herein are used to simplify reference when discussing particular figures or examples. For instance, references to downward (or other) or upward (or other) positions may be used to discuss aspects of a particular example or figure, but do not necessarily require a similar orientation or geometry in all installations or configurations. Unless otherwise defined or restricted, "essentially parallel" herein means a direction that lies within ±12 degrees of a reference direction (e.g., within ±6 degrees). For a path that is not linear, the path may be considered essentially parallel to a reference direction if a straight line between the endpoints of the path is essentially parallel to the reference direction or to a mean derivative of the path within a common frame of reference, since the reference direction is essentially parallel to the reference direction. Unless otherwise limited or defined, "substantially perpendicular" herein means a direction that lies within ±12 degrees (e.g., within ±6 degrees) from the perpendicular to a reference direction. For a path that is not linear, the path may be considered to be substantially perpendicular to a reference direction if a straight line between the endpoints of the path is substantially perpendicular to the reference direction or to a mean derivative of the path within a common frame of reference, since the reference direction is substantially perpendicular to the reference direction. Unless otherwise restricted or defined, "one-piece" and derivatives thereof (e.g., "one-piece") herein describe elements manufactured as a single piece without fasteners, adhesives, or the like to join individual components. For example, an element that is stamped, cast, or otherwise formed as a single piece from a single sheet of metal or using a single die, without rivets, screws, or adhesives to hold separately formed parts together, is a one-piece (and one-piece formed) element. By contrast, an element consisting of multiple parts that are first formed separately and subsequently joined together is not a one-piece (or one-piece formed) element. As used herein in connection with cable connectors, unless otherwise restricted or defined, 'axial' and related terms refer to an axial direction of an elongated cable being inserted into (or passing completely through) the connector in question. For example, in the case of a cylindrical cable being received through the housing and insert of a cable connector, an axial direction is a direction along a centerline of the cable within the housing and insert. Unless otherwise restricted or defined, 'radial' accordingly means a direction perpendicular to the axial direction, and the terms 'inward' and 'outward' mean movement transverse to the axial direction, respectively toward and away from a reference centerline. Unless otherwise specified or limited, the terms "about" and "approximately," as used herein in relation to a reference value, refer to deviations from the reference value of ±25% or less, including the endpoints of the range. Likewise, the term "substantially the same" (and the like), as used herein in relation to a reference value, refers to deviations from the reference value of less than ±15% (inclusive). Where specified, "substantially" may, in particular, denote a deviation in a numerical direction relative to a reference value. For example, "substantially less" than a reference value (and the like) means a value that deviates from the reference value by 15% or more, and "substantially more" than a reference value (and the like) means a value that deviates from the reference value by 15% or more. Unless otherwise limited or specified, "substantially identical" herein refers to two or more components or systems that are manufactured or used according to the same process and specification, with any variations between the components or systems being within the permissible tolerances for that process and specification. For example, two components may be considered substantially identical if they are manufactured using the same standardized manufacturing steps, the same materials, and within the same permissible dimensional tolerances (e.g., as specified for a particular process or product). The foregoing description of the disclosed embodiments is intended to enable any person skilled in the art to create or utilize the disclosure. Due to the advantages of this disclosure, various modifications of these embodiments are readily apparent to those skilled in the art, and the principles defined herein can be applied to other embodiments without departing from the spirit or scope of the disclosure. Therefore, the disclosure is not to be limited to the embodiments shown here, but is intended to apply as broadly as possible in accordance with the principles and new features disclosed herein. QUOTES INCLUDED IN THE DESCRIPTION This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature US 63 / 487,852

[0001]

Claims

A hydraulic tool, comprising: an electric motor having an outer rotor and a stator, the stator being at least partially received within the outer rotor; a hydraulic pump; and a transmission coupled between the electric motor and the hydraulic pump; wherein the electric motor drives the hydraulic pump via the transmission to pressurize hydraulic fluid within the hydraulic tool.The hydraulic tool of claim 1, further comprising: a mounting bracket coupled to the electric motor, the mounting bracket having a protrusion defining a through passage; and a pin inserted through the through passage and a portion of the transmission to couple the electric motor to the transmission.The hydraulic tool of claim 2, wherein the transmission comprises a mounting tab defining an opening, and wherein when the mounting bracket passageway aligns with the mounting tab opening, the pin is inserted through the opening and the passageway to couple the electric motor to the transmission.The hydraulic tool of claim 3, wherein the pin has a first end having a first diameter and a second end having a second diameter that is greater than the first diameter.The hydraulic tool of claim 4, wherein the second diameter of the second end of the pin is greater than a first diameter of the aperture and a third diameter of the through channel such that the second end of the pin cannot pass through the aperture or through channel.The hydraulic tool of claim 1, wherein the outer rotor comprises a plurality of magnet sets circumferentially disposed about the outer rotor.The hydraulic tool of claim 6, wherein at least one of the plurality of magnet sets comprises a magnet pair of equal polarity.The hydraulic tool of claim 7, wherein a first number of magnets within the outer rotor is twice as high as a second number of magnet sets within the outer rotor.The hydraulic tool of claim 6, wherein the outer rotor comprises a frame having one or more retaining ribs and one or more dividers, and wherein the one or more retaining ribs and the one or more dividers together retain the magnets within the outer rotor.The hydraulic tool of claim 9, wherein the frame comprises an integral fan.The hydraulic tool of claim 9, wherein the frame is a one-piece molded body.The hydraulic tool of claim 1, wherein pressurized hydraulic fluid actuates a hydraulic ram to actuate a die mounted to an end of the hydraulic ram and positioned within an opening of the hydraulic tool.The hydraulic tool of claim 1, wherein the electric motor is a brushless DC motor.The hydraulic tool of claim 1, further comprising: an annular printed circuit board fixed to the stator, the annular printed circuit board including a position sensor for detecting a position of the external rotor.The hydraulic tool of claim 1, further comprising: an adapter plate to removably couple the electric motor to the transmission, the adapter plate disposed between the stator and the transmission.A hydraulic tool comprising: a hydraulic pump; an electric motor comprising: a stator having a stator mount and a stator core supported by the stator mount, wherein the stator core defines a central bore; an outer rotor having a rotor shaft disposed within the central bore of the stator core, and wherein the outer rotor circumferentially surrounds the stator; and one or more magnet sets circumferentially disposed around the outer rotor, wherein one or more magnet sets comprise a pair of magnets of equal polarity; and wherein the electric motor drives the hydraulic pump via the outer rotor to pressurize the hydraulic fluid within the hydraulic tool.The hydraulic tool of claim 16, wherein a first number of magnets within the outer rotor is twice as high as a second number of magnet sets within the outer rotor.The hydraulic tool of claim 16, wherein the outer rotor comprises a frame having one or more retaining ribs and one or more dividers, and wherein the one or more retaining ribs and the one or more dividers together retain the magnets within the outer rotor.The hydraulic tool of claim 18, wherein the external rotor including the rotor shaft and the frame rotates relative to the stator and a stationary printed circuit board fixed to the stator.The hydraulic tool of claim 16, wherein the hydraulic tool comprises a gear box mounted between the electric motor and the hydraulic pump on the outer rotor shaft.The hydraulic tool of claim 20, further comprising: a mounting bracket coupled to the electric motor, the mounting bracket having a protrusion defining a through passage; and a pin inserted through the through passage and a portion of the transmission to couple the electric motor to the transmission.The hydraulic tool of claim 21, wherein the transmission comprises a mounting tab defining an opening, and wherein when the mounting bracket passageway aligns with the mounting tab opening, the pin is inserted through the opening and the passageway to couple the electric motor to the transmission.The hydraulic tool of claim 22, wherein a second diameter of a second end of the pin is greater than a first diameter of the aperture and a third diameter of the through channel such that the second end of the pin cannot pass through the aperture or through channel.A hydraulic tool comprising: an electric motor comprising: a stator having a stator mount and a stator core supported by the stator mount, the stator core defining a central bore; an outer rotor having a rotor shaft disposed within the central bore of the stator core, and the outer rotor being disposed circumferentially around the stator and radially outward of the stator; and one or more magnet sets disposed circumferentially around the outer rotor, the one or more magnet sets comprising a pair of magnets of equal polarity, wherein a first number of magnets within the outer rotor is twice as high as a second number of magnet sets within the outer rotor; a hydraulic pump; a transmission between the electric motor and the hydraulic pump; a mounting bracket coupled to the electric motor, the mounting bracket having a protrusion defining a through passage; and a pin inserted through the through passage and a portion of the transmission to couple the electric motor to the transmission; wherein the electric motor drives the hydraulic pump via the transmission to pressurize hydraulic fluid within the hydraulic tool.The hydraulic tool of claim 24, further comprising: an annular printed circuit board fixed to the stator, the annular printed circuit board including a position sensor for detecting a position of the external rotor.The hydraulic tool of claim 24, wherein the electric motor and the transmission together form a powertrain assembly, and wherein the powertrain assembly has a length of less than 90 mm.

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