Electric pump

Abstract

To provide a technique for facilitating the use of an electric pump.SOLUTION: An electric pump includes: a motor unit; and a pump unit driven by the motor unit and capable of discharging water. The motor unit includes: a body housing having a battery holding part capable of holding a battery pack; and an electric motor stored in the body housing and driving the pump unit. The battery pack can be used for the electric pump and an apparatus other than the electric pump.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The technology disclosed in this specification relates to an electric pump.

Background Art

[0002] Patent Document 1 discloses an electric pump. The electric pump includes a motor unit and a pump unit driven by the motor unit and capable of discharging water. The motor unit includes a main body housing having a battery holding portion capable of holding a battery pack, and an electric motor housed in the main body housing and driving the pump unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above electric pump, a dedicated battery pack is used. Therefore, it is desired to make the electric pump easier to use. This specification provides a technology that can make the electric pump easier to use.

Means for Solving the Problems

[0005] This specification discloses an electric pump. The electric pump includes a motor unit and a pump unit driven by the motor unit and capable of discharging water. The motor unit includes a main body housing having a battery holding portion capable of holding a battery pack, and an electric motor housed in the main body housing and driving the pump unit. The battery pack can be used for the electric pump and devices other than the electric pump.

[0006] According to the above configuration, in the electric pump, a highly versatile battery pack is used. This makes the electric pump easier to use.

Brief Description of the Drawings

[0007]

Figure 1

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Figure 10

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Mode for Carrying Out the Invention

[0008] Regarding representative and non-limiting specific examples of the present invention, it will be described in detail below with reference to the drawings. This detailed description is simply intended to show those skilled in the art the details for implementing preferred examples of the present invention, and is not intended to limit the scope of the present invention. Also, the additional features and inventions disclosed can be used separately or together with other features and inventions in order to provide an improved electric pump, its manufacturing method, and its usage method.

[0009] Moreover, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, and are described only for the purpose of explaining representative specific examples of the present invention in particular. Furthermore, the various features of the following representative specific examples, as well as the various features described in the claims, do not have to be combined as described in the specific examples here or in the order listed when providing additional and useful embodiments of the present invention.

[0010] All features described in this specification and / or the claims are intended to be disclosed individually and independently of each other as limitations to the initial disclosure and the specific matters described in the claims, apart from the configurations of the features described in the embodiments and / or the claims. Further, all descriptions regarding numerical ranges and groups or collections are made with the intention of disclosing intermediate configurations as limitations to the initial disclosure and the specific matters described in the claims.

[0011] In one or more embodiments, the electric motor may be a brushless motor including a stator and a rotor. The motor unit may be housed in a main body housing and may further include a control unit for driving the electric motor and a fan that rotates integrally with the rotor. The fan may generate an air flow inside the main body housing to cool the control unit by rotating.

[0012] According to the above configuration, it is possible to suppress the control unit from overheating.

[0013] In one or more embodiments, the motor unit may be detachable from the pump unit.

[0014] According to the above configuration, the pump unit can be easily replaced when the pump unit fails.

[0015] In one or more embodiments, one end of the motor unit may be supported by the pump unit. The other end of the motor unit may be a free end.

[0016] According to the above configuration, compared with the configuration in which one end and the other end of the motor unit are supported by the pump unit, the configuration of the electric pump can be simplified.

[0017] In one or more embodiments, the electric pump may be disposed below the main body housing when the electric pump is placed on the placement surface, and may further include a contact portion that contacts the placement surface.

[0018] According to the above configuration, it is possible to suppress the main body housing from contacting the placement surface.

[0019] In one or more embodiments, when the electric pump is placed on the placement surface, the battery holding portion may be disposed above the electric motor.

[0020] According to the above configuration, when the placement surface is wet with water, it is possible to suppress water from contacting the battery holding portion.

[0021] In one or more embodiments, the electric motor may rotate around a central axis extending in the front-rear direction. In the left-right direction orthogonal to each of the front-rear direction and the up-down direction orthogonal to the placement surface, the length of the main body housing may be shorter than the length of the contact portion.

[0022] In a configuration where the length of the main body housing is longer than the length of the contact portion, the electric pump may fall when an external force is applied to the main body housing. According to the above configuration, it is possible to suppress the electric pump from falling when an external force is applied to the main body housing.

[0023] In one or more embodiments, in the left-right direction, the length of the main body housing may be shorter than the length of the pump unit.

[0024] In a configuration where the pump is driven by an engine, in the left-right direction, the length of the main body housing becomes longer than the length of the pump unit. As a result, the pump becomes larger. According to the above configuration, in the left-right direction, since the length of the main body housing is shorter than the length of the pump unit, it is possible to suppress the electric pump from becoming larger.

[0025] In one or more embodiments, the electric pump may further include a handle that is fixed to the pump unit and has a grip portion that is gripped by a user. The center of gravity of the electric pump may be farther from the pump unit than the grip portion.

[0026] According to the above configuration, when the user grips the grip portion and lifts the electric pump, it is possible to suppress the electric pump from tilting so that the pump unit faces downward.

[0027] In one or more embodiments, the motor unit may be housed in the main body housing and may further include a control unit that drives the electric motor. When looking at the electric pump in the vertical direction orthogonal to the mounting surface with the electric pump mounted on the mounting surface, the electric motor may at least partially overlap with the battery holding portion.

[0028] According to the above configuration, it is possible to suppress the electric pump from increasing in size in the front-rear direction as compared with a configuration in which the electric motor does not overlap with the battery holding portion when looking at the electric pump in the vertical direction.

[0029] In one or more embodiments, when looking at the electric pump in the vertical direction with the electric pump mounted on the mounting surface, the electric motor may at least partially overlap with the control unit.

[0030] According to the above configuration, it is possible to suppress the electric pump from increasing in size in the front-rear direction as compared with a configuration in which the electric motor does not overlap with the control unit when looking at the electric pump in the vertical direction.

[0031] In one or more embodiments, the electric motor may rotate around a central axis extending in the front-rear direction. With respect to the left-right direction orthogonal to each of the front-rear direction and the vertical direction, the center of the battery holding portion and the center of the electric motor may be arranged on a first plane.

[0032] According to the above configuration, with respect to the left - right direction, compared with a configuration where the center of the battery holding part and the center of the electric motor are not arranged on the first plane, it is possible to suppress the electric pump from becoming larger in the left - right direction.

[0033] In one or more embodiments, with respect to the left - right direction, the center of the control unit may be arranged on the first plane.

[0034] According to the above configuration, with respect to the left - right direction, compared with a configuration where the center of the control unit is not arranged on the first plane, it is possible to suppress the electric pump from becoming larger in the left - right direction.

[0035] In one or more embodiments, the pump unit may have a discharge port for discharging water. The main body housing may be provided with an upper wall on which the battery holding part is arranged and which is arranged below the discharge port when the electric pump is placed on the placement surface. The upper wall may be inclined with respect to the placement surface when the electric pump is placed on the placement surface.

[0036] According to the above configuration, even if a part of the water discharged from the discharge port contacts the upper wall, the water flows on the upper wall and falls onto the placement surface. Thereby, it is possible to suppress the water from remaining on the upper wall.

[0037] In one or more embodiments, the battery holding part may hold two battery packs.

[0038] According to the above configuration, it is possible to increase the driving time of the electric pump or increase the output of the electric pump.

[0039] (First Embodiment) As shown in FIG. 1, the electric pump 2 is an electrical device that pumps a liquid, for example, water. The electric pump 2 is provided with a battery pack BP. The electric pump 2 is driven by the power of the battery pack BP. The battery pack BP is provided with a rechargeable secondary battery, for example, a lithium-ion battery. The battery pack BP is a highly versatile battery pack. The battery pack BP can also be used for electrical devices other than the electric pump 2. As shown in FIG. 2, for example, the battery pack BP can also be used for a reinforcing bar bundling machine 3 that bundles a plurality of reinforcing bars R using a wire W. Further, the battery pack BP is not limited to, for example, the electric pump 2 and the reinforcing bar bundling machine 3, and can also be used for electric tools such as an impact driver and a hammer drill, and gardening products such as a lawn mower, a brush cutter, a blower, a hedge trimmer, a chainsaw, a transporter, a snow remover, and a tiller.

[0040] As shown in FIG. 1, the electric pump 2 includes a motor unit 4, a pump unit 6, a handle 8, a throttle lever 10, and a base 12. Hereinafter, when the electric pump 2 is placed on a placement surface P (see FIG. 5), the direction orthogonal to the placement surface P is referred to as the vertical direction, the direction orthogonal to the vertical direction is referred to as the front-rear direction, and the direction orthogonal to the vertical direction and the front-rear direction is referred to as the left-right direction.

[0041] As shown in FIG. 3, the motor unit 4 includes a main body housing 20. The main body housing 20 is made of a resin material. The main body housing 20 includes a right main body housing 22 and a left main body housing 24. The right main body housing 22 and the left main body housing 24 have a shape in which the main body housing 20 is half-divided by a plane including the front-rear direction and the vertical direction. A housing space 26 (see FIG. 5) is defined between the right main body housing 22 and the left main body housing 24.

[0042] The main body housing 20 includes a right wall 30, a left wall 32, a lower wall 34, a rear upper wall 36 (see FIG. 5), a front upper wall 38, a rear wall 40, a front vertical wall 42, and a front horizontal wall 44.

[0043] As shown in FIG. 4, the right wall 30 has a first exhaust port 46. The first exhaust port 46 communicates the accommodation space 26 (see FIG. 5) with the space outside the main body housing 20.

[0044] As shown in FIG. 3, the left wall 32 has a second exhaust port 48. The second exhaust port 48 communicates the accommodation space 26 (see FIG. 5) with the space outside the main body housing 20.

[0045] As shown in FIG. 5, the lower wall 34 is inclined with respect to the placement surface P. The lower wall 34 extends toward the upper rear. The inclination angle of the lower wall 34 with respect to the placement surface P is 5 degrees or more and 30 degrees or less. The rear upper wall 36 is inclined with respect to the placement surface P. The rear upper wall 36 extends toward the lower rear. The inclination angle of the rear upper wall 36 with respect to the placement surface P is, for example, 5 degrees or more and 45 degrees or less. The inclination angle of the rear upper wall 36 with respect to the placement surface P is larger than the inclination angle of the lower wall 34 with respect to the placement surface P.

[0046] The front upper wall 38 is substantially parallel to the placement surface P. As shown in FIG. 3, a main power switch 50 is arranged on the front upper wall 38. The main power switch 50 accepts the user's operation to switch the on state and off state of the electric pump 2.

[0047] The front vertical wall 42 extends upward from the front end of the lower wall 34. The front vertical wall 42 is substantially parallel to the rear wall 40. The front horizontal wall 44 extends forward from the upper end of the front vertical wall 42. The front horizontal wall 44 is substantially parallel to the placement surface P.

[0048] As shown in FIG. 3, the main body housing 20 includes a throttle cover 52 and an intake cover 54 (see FIG. 4). The throttle cover 52 is fixed to the left main body housing 24. The throttle cover 52 is disposed rearward of the second exhaust port 48. A throttle wire 56 passes through the throttle cover 52. The throttle wire 56 extends forward from the throttle cover 52. The throttle wire 56 is fixed to a throttle lever 10 (see FIG. 1). The motor unit 4 further includes a detector 57 disposed inside the throttle cover 52, and the detector 57 detects the amount of pull of the throttle wire 56. In FIG. 3, the detector 57 is indicated by a dashed line.

[0049] As shown in FIG. 4, the intake cover 54 is fixed to the right main body housing 22. The intake cover 54 is disposed rearward of the first exhaust port 46. The intake cover 54 has an intake port 58. The intake port 58 communicates the accommodation space 26 (see FIG. 5) with the space outside the main body housing 20.

[0050] The main body housing 20 includes a board accommodation portion 62, a motor accommodation portion 64, and a battery holding portion 66. The board accommodation portion 62 is located at the lower part of the main body housing 20. The motor accommodation portion 64 is disposed above the board accommodation portion 62. The battery holding portion 66 is disposed above the motor accommodation portion 64.

[0051] As shown in FIG. 6, the battery holding portion 66 is disposed on the rear upper wall 36. The battery holding portion 66 includes a right rail 68, a left rail 70, and a connecting wall 72. The right rail 68 and the left rail 70 are rails for holding the battery pack BP (see FIG. 3) in the battery holding portion 66. The right rail 68 and the left rail 70 are slidably engaged with the rail 74 (see FIG. 5) of the battery pack BP. The right rail 68 is disposed at the right end of the rear upper wall 36 and extends from the rear end to the front end of the rear upper wall 36. The left rail 70 is disposed at the left end of the rear upper wall 36 and extends from the rear end to the front end of the rear upper wall 36. The front ends of the right rail 68 and the left rail 70 are connected to the connecting wall 72. As shown in FIG. 3, the battery pack BP is attached to the battery holding portion 66 by sliding the battery pack BP forward and upward. Also, the battery pack BP is removed from the battery holding portion 66 by sliding the battery pack BP backward and downward.

[0052] As shown in FIG. 7, the motor unit 4 includes a control unit 76, a battery terminal 78, a motor housing 80, an electric motor 82, a fan 84, and an output unit 86. The control unit 76, the motor housing 80, the electric motor 82, the fan 84, and the output unit 86 are disposed in the accommodation space 26.

[0053] The control unit 76 is disposed in the substrate accommodation portion 62. The control unit 76 is electrically connected to the main power switch 50, the battery terminal 78, and the electric motor 82. The control unit 76 operates by the power supplied from the battery pack BP via the battery terminal 78. The control unit 76 drives the electric motor 82 by supplying the power supplied from the battery pack BP to the electric motor 82.

[0054] The control unit 76 includes a control board 90 having a microcomputer and a plurality of switching elements, and a metal case 92. The switching elements are, for example, IGBTs or MOSFETs. The switching elements are switched between an on state and an off state by being controlled by the microcomputer. By switching the on state and the off state of the switching elements, the electric motor 82 is controlled. The control board 90 is housed in the case 92. The control board 90 and the case 92 are arranged along the lower wall 34. The case 92 is provided with heat dissipation fins 94 extending downward. In the front-rear direction, the battery holding portion 66 is arranged between the front end and the rear end of the control unit 76. The front end of the control unit 76 corresponds to the front end of the case 92, and the rear end of the control unit 76 corresponds to the rear end of the case 92. When looking at the electric pump 2 downward, the control unit 76 at least partially overlaps with the battery holding portion 66. As shown in FIG. 8, the length L1 in the left-right direction of the control unit 76 is shorter than the length L2 in the left-right direction of the battery holding portion 66 and the length L3 in the left-right direction of the main body housing 20, respectively. The length L1 is the length between the right end and the left end of the control unit 76. The right end of the control unit 76 corresponds to the right end of the case 92, and the left end of the control unit 76 corresponds to the left end of the case 92. Also, the length L2 is shorter than the length L3. The center 76a in the left-right direction of the control unit 76 and the center 66a in the left-right direction of the battery holding portion 66 are arranged on the first plane 96. The center 76a is the center between the right end and the left end of the case 92. The center 66a is the center between the right end and the left end of the battery holding portion 66. The first plane 96 is orthogonal to the placement surface P and is a plane including the front-rear direction and the up-down direction. Also, the first plane 96 is arranged at the boundary between the right main body housing 22 and the left main body housing 24. Also, the center of gravity G1 of the electric pump 2 is arranged on the first plane 96.

[0055] As shown in FIG. 7, the battery terminal 78 is disposed on the rear upper wall 36. The battery terminal 78 is exposed to the space outside the main body housing 20. The battery terminal 78 is electrically connected to a terminal (not shown) of the battery pack BP when the battery pack BP is held by the battery holding portion 66. In the front-rear direction, the battery terminal 78 is disposed between the front end and the rear end of the control unit 76. When looking at the electric pump 2 downward, the battery terminal 78 at least partially overlaps with the control unit 76. As shown in FIG. 8, the length L4 in the left-right direction of the battery terminal 78 is shorter than the length L1 in the left-right direction of the control unit 76. The center 78a in the left-right direction of the battery terminal 78 is disposed on the first plane 96. The center 78a corresponds to the center between the right end and the left end of the battery terminal 78.

[0056] As shown in FIG. 7, the motor housing 80 is disposed in the motor accommodating portion 64. The motor housing 80 has a plurality of motor air inlets 98 (see FIG. 8) at the rear end. In the up-down direction, the motor housing 80 is disposed between the battery holding portion 66 and the control unit 76. When looking at the electric pump 2 downward, the motor housing 80 at least partially overlaps with each of the battery holding portion 66, the control unit 76, and the battery terminal 78.

[0057] The electric motor 82 is accommodated in the motor housing 80. The electric motor 82 is supported by the main body housing 20 via the motor housing 80. The electric motor 82 is, for example, a DC motor. The electric motor 82 is, for example, an inner rotor type brushless motor. In a modified example, the electric motor 82 may be an outer rotor type brushless motor or a brushed motor. The maximum output value of the electric motor 82 may be 0.5 kW or more and 2.0 kW or less, for example, 0.5 kW or more and 1.5 kW or less, for example, 0.5 kW or more and 1.2 kW or less, for example, 0.5 kW or more and 1.0 kW or less.

[0058] In the vertical direction, the electric motor 82 is disposed below the battery holding portion 66 and above the control unit 76. When looking at the electric pump 2 downward, the electric motor 82 at least partially overlaps with each of the battery holding portion 66, the control unit 76, and the battery terminal 78. As shown in FIG. 8, the length L5 (i.e., the diameter) of the electric motor 82 in the left-right direction is shorter than the length L2 of the battery holding portion 66 in the left-right direction and longer than the length L4 of the battery terminal 78 in the left-right direction. The length L5 is substantially the same as the length L1. The center 82a of the electric motor 82 in the left-right direction is disposed on the first plane 96. The center 82a is the center between the right end and the left end of the electric motor 82.

[0059] As shown in FIG. 7, the electric motor 82 includes a stator 100 and a rotor 102. The diameter of the stator 100 corresponds to the diameter of the electric motor 82. Also, each of the right end and the left end of the stator 100 corresponds to each of the right end and the left end of the electric motor 82. The stator 100 includes a stator core 104 and a plurality of coils 106. Each coil 106 is wound around the stator core 104. The rotor 102 penetrates the stator 100 in the front-rear direction. The rotor 102 includes a rotor body 110 having a plurality of permanent magnets 108. The motor unit 4 further includes a shaft 112, and the shaft 112 penetrates the rotor body 110 in the front-rear direction. The shaft 112 extends in the front-rear direction. The rear end of the shaft 112 is rotatably supported by the motor housing 80 via a bearing 114. The front end of the shaft 112 is rotatably supported by the output unit 86 via a bearing 116. When the microcomputer of the control unit 76 selectively switches the switching element between the on state and the off state, the power of the battery pack BP is supplied to each coil 106. Due to the magnetic field generated in each coil 106, the rotor body 110 rotates around the central axis AX extending in the front-rear direction. Thereby, the shaft 112 rotates around the central axis AX.

[0060] The fan 84 is fixed to the shaft 112 outside the motor housing 80. The fan 84 is a centrifugal fan. In a modified example, the fan 84 may be an axial fan. The fan 84 rotates around the central axis AX integrally with the shaft 112.

[0061] When the fan 84 rotates, as shown in FIG. 8, an air flow is generated in the accommodation space 26. First, the air passes through the intake port 58 and flows into the accommodation space 26 from the space outside the main body housing 20. In the drawings, the air flow is indicated by an arrow line indicated by the reference symbol F. The inflowing air flows downward along the flow straightening plate 54a of the intake cover 54, and then flows in a clockwise direction around the control unit 76 looking forward to the electric pump 2. When the air touches the heat dissipation fins 94, the case 92 is cooled. Thereby, the control board 90 is cooled. As shown in FIG. 7, thereafter, the air passes between the control unit 76 and the battery terminal 78 and flows toward the plurality of motor intake ports 98. Thereby, the control unit 76 and the battery terminal 78 are cooled.

[0062] The air passes through the motor intake port 98 and flows into the inside of the motor housing 80. The inflowing air flows forward in the motor housing 80. Thereby, the electric motor 82 is cooled. When the air flows to the fan 84, it is sent in a direction away from the central axis AX by the fan 84. Thereafter, the air passes through the first exhaust port 46 (see FIG. 4) and the second exhaust port 48 (see FIG. 3) and is discharged to the space outside the main body housing 20.

[0063] As shown in FIG. 9, the output unit 86 is disposed at the front of the motor housing portion 64. The output unit 86 penetrates the front end of the main body housing 20. The output unit 86 is fixed to the front end of the main body housing 20. The output unit 86 is fixed to the front end of the motor housing 80.

[0064] The output unit 86 includes a mount base 120, a support member 122, and a spindle 124.

[0065] The mount base 120 includes a cylindrical portion 126 and a partition portion 128. The inner surface of the cylindrical portion 126 has a substantially circular cross-sectional shape. As shown in FIG. 3, the cylindrical portion 126 has a plurality of (four in this embodiment) screw holes 130. The screw holes 130 are arranged on the front surface of the cylindrical portion 126. The front surface of the cylindrical portion 126 corresponds to the front surface of the motor unit 4.

[0066] As shown in FIG. 9, the partition portion 128 has a substantially disc shape. The partition portion 128 is arranged inside the cylindrical portion 126. The partition portion 128 is connected to the inner surface of the cylindrical portion 126. The partition portion 128 divides the internal space of the cylindrical portion 126 into a front space 132 and a rear space 134. The shaft 112 passes through the partition portion 128. The partition portion 128 rotatably supports the shaft 112 via a bearing 116. The fan 84 is arranged in the rear space 134.

[0067] The support member 122 is arranged in the front space 132. The support member 122 is fixed to the front surface of the partition portion 128.

[0068] The spindle 124 extends in the front-rear direction. The spindle 124 passes through the support member 122 in the front-rear direction. The spindle 124 is rotatably supported by the support member 122 via a bearing 136. The rear end of the spindle 124 is fitted to the front end of the shaft 112. The spindle 124 rotates around the central axis AX integrally with the shaft 112.

[0069] As shown in FIG. 5, the pump unit 6 is fixed to the front end of the motor unit 4 by screwing a screw (not shown) into a plurality of screw holes 130 (see FIG. 3) of the mount base 120. The pump unit 6 is detachable from the motor unit 4. The pump unit 6 supports the front end (i.e., the fixed end) of the motor unit 4 and does not support the rear end (i.e., the free end) of the motor unit 4. That is, the pump unit 6 supports the motor unit 4 with a cantilever structure.

[0070] As shown in FIG. 10, the length L6 of the pump unit 6 in the left-right direction is longer than the length L3 of the main body housing 20 in the left-right direction. In the left-right direction, the main body housing 20 is disposed between the left end and the right end of the pump unit 6.

[0071] As shown in FIG. 11, the pump unit 6 includes a rear pump housing 140, a front pump housing 142, an inner housing 144, and an impeller 146.

[0072] The rear pump housing 140 has a flat plate shape along the vertical and left-right directions. The rear surface of the rear pump housing 140 abuts against the front end of the mount base 120 (i.e., the front end of the motor unit 4). The rear pump housing 140 has a through hole 148. A spindle 124 passes through the through hole 148. A seal body 149 is disposed between the spindle 124 and the rear pump housing 140. The seal body 149 suppresses the passage of liquid between the spindle 124 and the rear pump housing 140. The spindle 124 is rotatably supported by the rear pump housing 140 via the seal body 149.

[0073] The front pump housing 142 is disposed on the front side of the rear pump housing 140. The front pump housing 142 includes a housing portion 150, a suction portion 152, and a discharge portion 154.

[0074] The housing portion 150 is fixed to the rear pump housing 140 by a screw 156 (see FIG. 1). A seal ring 157 is disposed between the housing portion 150 and the rear pump housing 140. As shown in FIG. 1, the housing portion 150 has a drain port 158. The drain port 158 communicates the inside and the outside of the housing portion 150. Usually, the drain port 158 is closed by a cap 159.

[0075] The suction part 152 extends forward from the front end of the housing part 150. The suction part 152 is arranged above the drain port 158. The suction part 152 is attached to a water supply device (not shown). As shown in FIG. 11, the suction part 152 has a suction passage 160 extending in the front-rear direction. In FIGS. 5 and 11, the drain port 158 and the cap 159 are not shown. The suction passage 160 communicates with the internal space of the housing part 150. Hereinafter, the front end of the suction passage 160 may be referred to as a suction port 162. The suction passage 160 is arranged above the spindle 124. As shown in FIG. 5, the suction passage 160 is arranged below each of the battery holding part 66 and the battery terminal 78. The suction passage 160 is arranged above the control unit 76.

[0076] As shown in FIG. 1, the discharge part 154 extends upward from the upper end of the housing part 150 and then bends and extends leftward. As shown in FIG. 11, the discharge part 154 has a discharge passage 164. The discharge passage 164 communicates with the internal space of the housing part 150. The discharge passage 164 extends upward and then bends and extends leftward. Hereinafter, the left end of the discharge passage 164 may be referred to as a discharge port 166. In FIGS. 5 and 11, the position of the discharge port 166 is shown by a dashed line. The discharge port 166 is arranged above the suction port 162. As shown in FIG. 5, the discharge port 166 is arranged above each of the battery holding part 66 and the battery terminal 78.

[0077] As shown in FIG. 11, the discharge part 154 has a water injection port 168. The water injection port 168 communicates the discharge passage 164 with the external space of the pump unit 6. Normally, the water injection port 168 is closed by a cap 170.

[0078] The inner housing 144 has a volute chamber 174 inside. The volute chamber 174 extends in a spiral shape around the central axis AX. When the inner housing 144 is accommodated in the accommodating portion 150, an intake space 176 and a discharge space 178 are formed between the inner housing 144 and the accommodating portion 150. The intake space 176 and the discharge space 178 do not communicate directly. The volute chamber 174 communicates with the intake passage 160 via the intake space 176. The volute chamber 174 communicates with the discharge passage 164 via the discharge space 178.

[0079] The impeller 146 is disposed in the volute chamber 174. The impeller 146 is fitted to the front end of the spindle 124. As shown in FIG. 5, the impeller 146 is disposed below each of the battery holding portion 66 and the battery terminal 78. The impeller 146 is disposed above the control unit 76. The diameter of the impeller 146 is larger than the diameter of the electric motor 82.

[0080] When operating the electric pump 2, first, as shown in FIG. 5, after removing the cap 170, water is poured into the inside of the pump unit 6 from the water injection port 168. Thereby, the inside of the pump unit 6 is filled with water. Next, the electric motor 82 is operated. Thereby, the impeller 146 rotates integrally with the shaft 112 and the spindle 124 around the central axis AX. As shown in FIG. 11, when the impeller 146 rotates, water supplied from a water supply device (not shown) flows into the intake passage 160 from the intake port 162. The flowing-in water flows into the volute chamber 174 after passing through the intake passage 160 and the intake space 176 in sequence. Next, the water is sent in a direction away from the central axis AX by the impeller 146 and flows in the volute chamber 174. Finally, the water is discharged from the discharge port 166 after passing through the discharge space 178 and the discharge passage 164 in sequence. Next, when the operation of the electric motor 82 (see FIG. 5) is stopped, the rotation of the impeller 146 stops. Thereby, the discharge of water from the discharge port 166 stops. Finally, as shown in FIG. 1, the cap 159 is removed from the pump unit 6. Thereby, the water is discharged from the drain port 158 to the outside of the pump unit 6.

[0081] The handle 8 has a substantially U-shaped configuration. The handle 8 includes a right connection portion 182, a left connection portion 184, and a grip portion 186.

[0082] One end of the right connection portion 182 and one end of the left connection portion 184 are fixed to the rear pump housing 140. The right connection portion 182 and the left connection portion 184 extend rearward and upward from the rear pump housing 140.

[0083] The grip portion 186 is gripped by the user. The grip portion 186 is connected to the other end of the right connection portion 182 and the other end of the left connection portion 184. The grip portion 186 extends in the left-right direction. As shown in FIG. 5, the grip portion 186 is disposed above each of the discharge portion 154, the battery pack BP, the battery holder 66, and the battery terminal 78. In the front-rear direction, the grip portion 186 is disposed at a position farthest from the rear pump housing 140. In the front-rear direction, the grip portion 186 is disposed rearward of the rear pump housing 140. In the front-rear direction, the grip portion 186 is disposed forward of the center of gravity G1 of the control unit 76, the battery terminal 78, the electric motor 82, and the electric pump 2. In the front-rear direction, the center of gravity G1 of the electric pump 2 is farther from the rear pump housing 140 than the grip portion 186. As shown in FIG. 10, in the left-right direction, the center 186a of the grip portion 186 is disposed on the first plane 96. The center 186a is the center between the right end and the left end of the grip portion 186.

[0084] The throttle lever 10 is attached to the right connection portion 182. The throttle lever 10 is operated by the user. When the throttle lever 10 is operated, the throttle wire 56 (see FIG. 3) is pulled. The control unit 76 (see FIG. 5) drives the electric motor 82 (see FIG. 5) based on the amount of pull of the throttle wire 56 detected by the detector 57 (see FIG. 3). As the operation amount of the throttle lever 10 increases (i.e., as the amount of pull of the throttle wire 56 increases), the rotational speed of the electric motor 82 (i.e., the rotational speed of the shaft 112) gradually increases from zero.

[0085] As shown in FIG. 5, the base 12 is fixed to the lower end of the rear pump housing 140. The base 12 has a flat plate shape along the front-rear direction and the left-right direction. The base 12 is disposed below the main body housing 20. When the electric pump 2 is placed on the placement surface P, only the base 12 contacts the placement surface P. In the front-rear direction, the front end of the base 12 is disposed in front of the main body housing 20 and the rear pump housing 140. The rear end of the base 12 is disposed behind the main body housing 20 and the battery pack BP. As shown in FIG. 10, the length L7 of the base 12 in the left-right direction is longer than the lengths L3 of the main body housing 20 and L6 of the pump unit 6 in the left-right direction, respectively. In the left-right direction, the main body housing 20 and the pump unit 6 are disposed between the left end and the right end of the base 12. When looking at the electric pump 2 downward, the entire main body housing 20 overlaps with the base 12.

[0086] (Effect) The electric pump 2 of the present embodiment includes a motor unit 4 and a pump unit 6 that is driven by the motor unit 4 and can discharge water. The motor unit 4 includes a main body housing 20 having a battery holding portion 66 capable of holding the battery pack BP, and an electric motor 82 that is housed in the main body housing 20 and drives the pump unit 6. The battery pack BP can be used for the electric pump 2 and a reinforcing bar tying machine 3 (an example of equipment) other than the electric pump 2.

[0087] According to the above configuration, in the electric pump 2, a highly versatile battery pack BP is used. Thereby, the electric pump 2 can be made easier to use.

[0088] Further, the electric motor 82 is a brushless motor including a stator 100 and a rotor 102. The motor unit 4 is housed in the main body housing 20, and further includes a control unit 76 that drives the electric motor 82, and a fan 84 that rotates integrally with the rotor 102. By rotating, the fan 84 generates an air flow inside the main body housing 20 that cools the control unit 76.

[0089] According to the above configuration, it is possible to prevent the control unit 76 from overheating.

[0090] Also, the motor unit 4 is detachable from the pump unit 6.

[0091] According to the above configuration, when the pump unit 6 fails, the pump unit 6 can be easily replaced.

[0092] One end of the motor unit 4 is supported by the pump unit 6. The other end of the motor unit 4 is a free end.

[0093] According to the above configuration, compared with a configuration in which one end and the other end of the motor unit 4 are supported by the pump unit 6, the configuration of the electric pump 2 can be simplified.

[0094] Also, the electric pump 2 is disposed below the main body housing 20 when the electric pump 2 is placed on the placement surface P, and further includes a base 12 (an example of a contact portion) that contacts the placement surface P.

[0095] According to the above configuration, it is possible to prevent the main body housing 20 from contacting the placement surface P.

[0096] Also, when the electric pump 2 is placed on the placement surface P, the battery holding portion 66 is disposed above the electric motor 82.

[0097] According to the above configuration, when the placement surface P is wet with water, it is possible to suppress water from coming into contact with the battery holding portion 66.

[0098] Further, the electric motor 82 rotates around a central axis AX extending in the front-rear direction. With respect to the left-right direction orthogonal to each of the front-rear direction and the up-down direction orthogonal to the placement surface P, the length L3 of the main body housing 20 is shorter than the length L7 of the base 12.

[0099] In a configuration where the length L3 of the main body housing 20 is longer than the length L7 of the base 12, the electric pump 2 may fall over when an external force is applied to the main body housing 20. According to the above configuration, it is possible to suppress the electric pump 2 from falling over when an external force is applied to the main body housing 20.

[0100] Also, with respect to the left-right direction, the length L3 of the main body housing 20 is shorter than the length L6 of the pump unit 6.

[0101] In a configuration where the pump is driven by an engine, with respect to the left-right direction, the length L3 of the main body housing 20 becomes longer than the length L6 of the pump unit 6. As a result, the pump becomes larger in size. According to the above configuration, since the length L3 of the main body housing 20 is shorter than the length L6 of the pump unit 6 with respect to the left-right direction, it is possible to suppress the electric pump 2 from becoming larger in size.

[0102] Further, the electric pump 2 is fixed to the pump unit 6 and further includes a handle 8 having a gripping portion 186 that is gripped by the user. The center of gravity G1 of the electric pump 2 is farther from the pump unit 6 than the gripping portion 186.

[0103] According to the above configuration, when the user grips the gripping portion 186 and lifts the electric pump 2, it is possible to suppress the electric pump 2 from tilting so that the pump unit 6 faces downward.

[0104] Further, the motor unit 4 is housed in the main body housing 20 and further includes a control unit 76 that drives the electric motor 82. When looking at the electric pump 2 in the vertical direction perpendicular to the mounting surface P with the electric pump 2 mounted on the mounting surface P, the electric motor 82 at least partially overlaps with the battery holding portion 66.

[0105] According to the above configuration, it is possible to suppress the electric pump 2 from becoming larger in the front-rear direction as compared with a configuration in which the electric motor 82 does not overlap with the battery holding portion 66 when looking at the electric pump 2 in the vertical direction.

[0106] Also, when looking at the electric pump 2 in the vertical direction with the electric pump 2 mounted on the mounting surface P, the electric motor 82 at least partially overlaps with the control unit 76.

[0107] According to the above configuration, it is possible to suppress the electric pump 2 from becoming larger in the front-rear direction as compared with a configuration in which the electric motor 82 does not overlap with the control unit 76 when looking at the electric pump 2 in the vertical direction.

[0108] Also, the electric motor 82 rotates around a central axis AX extending in the front-rear direction. With respect to the left-right direction orthogonal to each of the front-rear direction and the vertical direction, the center 66a of the battery holding portion 66 and the center 82a of the electric motor 82 are arranged on the first plane 96.

[0109] According to the above configuration, it is possible to suppress the electric pump 2 from becoming larger in the left-right direction as compared with a configuration in which the center 66a of the battery holding portion 66 and the center 82a of the electric motor 82 are not arranged on the first plane 96 with respect to the left-right direction.

[0110] Also, with respect to the left-right direction, the center 76a of the control unit 76 is arranged on the first plane 96.

[0111] According to the above configuration, in the left - right direction, compared with a configuration where the center 76a of the control unit 76 is not arranged on the first plane 96, it is possible to suppress the enlargement of the electric pump 2 in the left - right direction.

[0112] Further, the pump unit 6 has a discharge port 166 for discharging water. The main body housing 20 is provided with a battery holding portion 66, and includes a rear upper wall 36 (an example of an upper wall) that is arranged below the discharge port 166 when the electric pump 2 is placed on the placement surface P. The rear upper wall 36 is inclined with respect to the placement surface P when the electric pump 2 is placed on the placement surface P.

[0113] According to the above configuration, even if a part of the water discharged from the discharge port 166 comes into contact with the rear upper wall 36, the water flows on the rear upper wall 36 and falls onto the placement surface P. Thereby, it is possible to suppress the water from remaining on the rear upper wall 36.

[0114] (Second Embodiment) In the second embodiment, only the differences from the first embodiment will be described. As shown in FIG. 12, the control unit 76 is arranged on the rear side of the electric motor 82. The control unit 76 is arranged along a plane including the vertical direction and the horizontal direction. When looking at the electric pump 2 in the forward direction, the control unit 76 at least partially overlaps with each of the electric motor 82 and the impeller 146. By sliding the battery pack BP parallel to the placement surface P on the battery holding portion 66, the battery pack BP is attached to and detached from the battery holding portion 66. The mounting direction of the battery pack BP to the battery holding portion 66 may be the forward direction, the left direction, or the right direction.

[0115] (Third Embodiment) In the third embodiment, only the differences from the first embodiment will be described. As shown in FIG. 13, the battery holding portion 66 is disposed on the rear side of the electric motor 82. The battery holding portion 66 is disposed along a plane including the vertical direction and the horizontal direction. When viewing the electric pump 2 in the forward direction, the battery holding portion 66 at least partially overlaps with each of the electric motor 82 and the impeller 146. The mounting direction of the battery pack BP to the battery holding portion 66 may be downward, leftward, or rightward.

[0116] (Fourth Embodiment) In the fourth embodiment, only the differences from the first embodiment will be described. As shown in FIG. 14, the substrate accommodating portion 62 is disposed above the motor accommodating portion 64. The substrate accommodating portion 62 extends rearward beyond the rear end of the motor accommodating portion 64.

[0117] The battery holding portion 66 is disposed on the rear side of the electric motor 82. The battery holding portion 66 is disposed in the motor accommodating portion 64. The battery holding portion 66 is disposed along a plane including the vertical direction and the horizontal direction. When viewing the electric pump 2 in the forward direction, the battery holding portion 66 at least partially overlaps with each of the electric motor 82 and the impeller 146. The control unit 76 is disposed above each of the electric motor 82 and the battery holding portion 66. The mounting direction of the battery pack BP to the battery holding portion 66 may be leftward or rightward.

[0118] (Fifth Embodiment) In the fifth embodiment, only the differences from the fourth embodiment will be described. As shown in FIG. 15, the battery holding portion 66 is disposed at the lower rear of the substrate housing portion 62. The battery holding portion 66 is above the electric motor 82 and below the control unit 76. The battery holding portion 66 is disposed along a plane including the front-rear direction and the left-right direction. In the front-rear direction, the battery holding portion 66 is disposed behind the center of the control unit 76 in the front-rear direction. When looking at the electric pump 2 downward, the battery holding portion 66 at least partially overlaps with the control unit 76. The mounting direction of the battery pack BP to the battery holding portion 66 may be the front direction, the left direction, or the right direction.

[0119] (Sixth Embodiment) In the sixth embodiment, only the differences from the first embodiment will be described. As shown in FIG. 16, the control unit 76 is disposed behind the electric motor 82. The control unit 76 is disposed along a plane including the vertical direction and the left-right direction. The battery holding portion 66 is disposed behind the control unit 76. The battery holding portion 66 is disposed along a plane including the vertical direction and the left-right direction. When looking at the electric pump 2 forward, the battery holding portion 66 at least partially overlaps with each of the control unit 76, the electric motor 82, and the impeller 146. The mounting direction of the battery pack BP to the battery holding portion 66 may be the downward direction, the left direction, or the right direction.

[0120] (Seventh Embodiment) In the seventh embodiment, only the differences from the first embodiment will be described. As shown in FIG. 17, the control unit 76 is disposed behind the electric motor 82. The control unit 76 is disposed along a plane including the vertical direction and the left-right direction.

[0121] The electric pump 2 includes two battery packs BP. Hereinafter, one battery pack BP is referred to as the first battery pack BP1, and the other battery pack BP is referred to as the second battery pack BP2.

[0122] The battery holding part 66 includes a first battery holding part 200 and a second battery holding part 202. The first battery holding part 200 holds the first battery pack BP1. The first battery pack BP1 is detachable from the first battery holding part 200. The mounting direction of the first battery pack BP1 to the first battery holding part 200 may be the forward direction, the rearward direction, or the leftward direction. The second battery holding part 202 holds the second battery pack BP2. The second battery pack BP2 is detachable from the second battery holding part 202. The mounting direction of the second battery pack BP2 to the second battery holding part 202 may be the forward direction, the rearward direction, or the rightward direction.

[0123] The first battery holding part 200 and the second battery holding part 202 are arranged on the rear upper wall 36 of the main body housing 20. The first battery holding part 200 and the second battery holding part 202 are arranged along a plane including the front-rear direction and the left-right direction. The first battery holding part 200 and the second battery holding part 202 are arranged side by side in the left-right direction. When looking at the electric pump 2 downward, the center 66a between the right end of the first battery holding part 200 and the left end of the second battery holding part 202 is arranged on the central axis AX. The center 66a between the right end of the first battery holding part 200 and the left end of the second battery holding part 202 corresponds to the left-right center 66a of the battery holding part 66. The first battery holding part 200 and the second battery holding part 202 are arranged above the electric motor 82 and the control unit 76 respectively. When looking at the electric pump 2 downward, the first battery holding part 200 and the second battery holding part 202 at least partially overlap with the electric motor 82 and the control unit 76 respectively.

[0124] (Effect) In this embodiment, the battery holding part 66 holds two battery packs BP.

[0125] According to the above configuration, the driving time of the electric pump 2 can be extended or the output of the electric pump 2 can be increased.

[0126] (Eighth Embodiment) In the eighth embodiment, only the differences from the seventh embodiment will be described. As shown in FIG. 18, the control unit 76 is disposed below the electric motor 82. The control unit 76 is disposed along a plane including the front-rear direction and the left-right direction.

[0127] The first battery holding portion 200 and the second battery holding portion 202 are disposed on the rear wall 40. The first battery holding portion 200 and the second battery holding portion 202 are disposed along a plane including the vertical direction and the left-right direction. The first battery holding portion 200 and the second battery holding portion 202 are disposed behind the electric motor 82. When looking at the electric pump 2 in the forward direction, the first battery holding portion 200 and the second battery holding portion 202 at least partially overlap with the electric motor 82 and the impeller 146, respectively. The mounting direction of the first battery pack BP1 to the first battery holding portion 200 may be downward or leftward. The mounting direction of the second battery pack BP2 to the second battery holding portion 202 may be downward or rightward.

[0128] (Ninth Embodiment) In the ninth embodiment, only the differences from the seventh embodiment will be described. As shown in FIG. 19, the control unit 76 is disposed along a plane including the front-rear direction and the left-right direction. The control unit 76 is disposed below each of the electric motor 82, the first battery holding portion 200, and the second battery holding portion 202. When looking at the electric pump 2 in the downward direction, the control unit 76 at least partially overlaps with each of the electric motor 82, the first battery holding portion 200, and the second battery holding portion 202.

[0129] (Tenth Embodiment) In the tenth embodiment, only the differences from the seventh embodiment will be described. As shown in FIG. 20, the control unit 76 is disposed along a plane including the front-rear direction and the left-right direction. The control unit 76 is disposed below each of the electric motor 82, the first battery holding portion 200, and the second battery holding portion 202.

[0130] The first battery holding part 200 and the second battery holding part 202 are arranged above the electric motor 82. The first battery holding part 200 and the second battery holding part 202 are arranged side by side in the front-rear direction. The mounting direction of the first battery pack BP1 to the first battery holding part 200 may be the left direction or the right direction. The mounting direction of the second battery pack BP2 to the second battery holding part 202 may be the left direction or the right direction.

[0131] (Example 11) In the eleventh embodiment, only the differences from the seventh embodiment will be described. As shown in FIG. 21, the control unit 76 is arranged below the electric motor 82. The control unit 76 is arranged along a plane including the front-rear direction and the left-right direction.

[0132] The main body housing 20 includes a protruding part 210 that protrudes upward from the upper rear part of the motor housing part 64. The first battery holding part 200 is arranged at the rear end of the protruding part 210. The first battery holding part 200 is arranged along a plane including the vertical direction and the left-right direction. The mounting direction of the first battery pack BP1 to the first battery holding part 200 may be the left direction or the right direction.

[0133] The second battery holding part 202 is arranged at the rear end of the motor housing part 64. The second battery holding part 202 is arranged below the first battery holding part 200. The second battery holding part 202 is arranged at the rear side of the electric motor 82. The second battery holding part 202 is arranged along a plane including the vertical direction and the left-right direction. The mounting direction of the second battery pack BP2 to the second battery holding part 202 may be the left direction or the right direction.

[0134] (Example 12) In the twelfth embodiment, only the differences from the seventh embodiment will be described. As shown in FIG. 22, the front upper wall 38 of the main body housing 20 extends from the front end toward the upper rear side. The rear upper wall 36 of the main body housing 20 extends from the front end toward the lower rear side.

[0135] The first battery holding part 200 and the second battery holding part 202 are arranged on the rear upper wall 36. The first battery holding part 200 is arranged above the electric motor 82. The mounting direction of the first battery pack BP1 to the first battery holding part 200 may be the left direction or the right direction. The second battery holding part 202 is arranged behind the first battery holding part 200. The second battery holding part 202 is arranged above the control unit 76. The mounting direction of the second battery pack BP2 to the second battery holding part 202 may be the left direction or the right direction.

[0136] The control unit 76 is arranged below the electric motor 82. The control unit 76 is arranged along a plane including the front-rear direction and the left-right direction.

[0137] (Example 13) In the 13th embodiment, only the differences from the 7th embodiment will be described. As shown in FIG. 23, the control unit 76 is arranged behind the electric motor 82. The control unit 76 is arranged along a plane including the up-down direction and the left-right direction. The first battery holding part 200 and the second battery holding part 202 are arranged behind the control unit 76. The first battery holding part 200 and the second battery holding part 202 are arranged along a plane including the up-down direction and the left-right direction. The mounting direction of the first battery pack BP1 to the first battery holding part 200 may be the downward direction or the left direction. The mounting direction of the second battery pack BP2 to the second battery holding part 202 may be the downward direction or the right direction.

[0138] (Example 14) In the 14th embodiment, only the differences from the 7th embodiment will be described. As shown in FIG. 24, the control unit 76 is arranged below the electric motor 82. The control unit 76 is arranged along a plane including the front-rear direction and the left-right direction.

[0139] The main body housing 20 has a first recess 220 that is recessed leftward from the right wall 30 and a second recess 222 that is recessed rightward from the left wall 32. The first battery holding portion 200 and the second battery holding portion 202 are disposed between the first recess 220 and the second recess 222. The first battery holding portion 200 and the second battery holding portion 202 are disposed along a plane including the vertical direction and the front-rear direction. The first battery pack BP1 is held by the first battery holding portion 200 within the first recess 220. The mounting direction of the first battery pack BP1 to the first battery holding portion 200 is downward. The second battery pack BP2 is held by the second battery holding portion 202 within the second recess 222. The mounting direction of the second battery pack BP2 to the second battery holding portion 202 is downward.

[0140] (Example 15) In the 15th embodiment, only the differences from the 7th embodiment will be described. As shown in FIG. 25, the control unit 76 is disposed below the electric motor 82. The control unit 76 is disposed along a plane including the front-rear direction and the left-right direction.

[0141] The first battery holding portion 200 is disposed on the rear upper wall 36. The first battery holding portion 200 is disposed above the electric motor 82 and the control unit 76. The first battery holding portion 200 is disposed along a plane including the front-rear direction and the left-right direction. The mounting direction of the first battery pack BP1 to the first battery holding portion 200 may be forward, leftward, or rightward.

[0142] The second battery holding portion 202 is disposed on the rear wall 40. The second battery holding portion 202 is disposed behind the electric motor 82. The second battery holding portion 202 is disposed along a plane including the vertical direction and the left-right direction. The mounting direction of the second battery pack BP2 to the second battery holding portion 202 may be downward, leftward, or rightward.

[0143] (Example 16) In the 16th embodiment, only the differences from the 7th embodiment will be described. As shown in FIG. 26, the control unit 76 is disposed on the rear side of the electric motor 82. The control unit 76 is disposed along a plane including the vertical direction and the horizontal direction.

[0144] The first battery holding portion 200 and the second battery holding portion 202 are disposed on the rear side of the control unit 76. The main body housing 20 includes a protruding portion 230 that protrudes rearward from the rear end of the motor housing portion 64. The first battery holding portion 200 is disposed on the upper wall 232 of the protruding portion 230. The second battery holding portion 202 is disposed on the lower wall 234 of the protruding portion 230. The first battery holding portion 200 and the second battery holding portion 202 are disposed along a plane including the front-rear direction and the left-right direction. The mounting direction of the first battery pack BP1 to the first battery holding portion 200 may be the front direction, the left direction, or the right direction. The mounting direction of the second battery pack BP2 to the second battery holding portion 202 may be the downward direction, the left direction, or the right direction.

[0145] (Modification) The other end of the motor unit 4 according to an embodiment may be fixed to the base 12.

[0146] In the electric pump 2 according to an embodiment, at least one of the center 66a of the battery holding portion 66, the center 82a of the electric motor 82, the center 76a of the control unit 76, the center 186a of the gripping portion 186, and the center of gravity G1 of the electric pump 2 may not be disposed on the first plane 96.

[0147] In the motor unit 4 according to an embodiment, the throttle cover 52 may be fixed to the right main body housing 22. The intake cover 54 may be fixed to the left main body housing 24.

[0148] In the motor unit 4 according to an embodiment, the throttle wire 56 may extend rearward, upward, or downward from the throttle cover 52.

Explanation of Symbols

[0149] 2: Electric pump 3: Steel bar tying machine 4: Motor unit 6: Pump unit 8: Handle 12: Base 20: Main body housing 26: Accommodation space 36: Rear upper wall 62: Substrate accommodation part 64: Motor accommodation part 66: Battery holding part 66a: Center 76: Control unit 76a: Center 82: Electric motor 82a: Center 84: Fan 86: Output unit 96: First plane 100: Stator 102: Rotor 112: Shaft 124: Spindle 140: Rear pump housing 142: Front pump housing 146: Impeller 162: Suction port 166: Discharge port 174: Volute chamber 186: Gripping part 200: First battery holding part 202: Second battery holding part AX: Central axis BP: Battery pack G1: Center of gravity P: Placing surface

Claims

1. An electric pump, A motor unit; a pump unit driven by the motor unit and capable of discharging water, The motor unit includes: a main body housing including a battery holding portion capable of holding a battery pack; an electric motor housed in the main body housing and driving the pump unit; The battery pack can be used for the electric pump and for devices other than the electric pump.

2. the electric motor is a brushless motor having a stator and a rotor, The motor unit includes: a control unit accommodated in the main body housing and configured to drive the electric motor; A fan that rotates integrally with the rotor, The electric pump according to claim 1 , wherein the fan generates an airflow inside the main body housing by rotating to cool the control unit.

3. The electric pump according to claim 1 or 2, wherein the motor unit is detachable from the pump unit.

4. One end of the motor unit is supported by the pump unit, The electric pump according to claim 1 , wherein the other end of the motor unit is a free end.

5. The electric pump according to claim 1 , further comprising a contact portion that is disposed below the main body housing when the electric pump is placed on a mounting surface and that contacts the mounting surface.

6. The electric pump according to claim 5 , wherein the battery holding portion is disposed above the electric motor when the electric pump is placed on the placement surface.

7. The electric motor rotates about a central axis extending in a front-rear direction, 7. The electric pump according to claim 5, wherein a length of the main body housing in a left-right direction perpendicular to both the front-rear direction and the up-down direction perpendicular to the placement surface is shorter than a length of the contact portion.

8. The electric pump according to claim 7 , wherein the length of the main body housing in the left-right direction is shorter than the length of the pump unit.

9. a handle fixed to the pump unit and having a grip portion to be gripped by a user; The electric motor rotates about a central axis extending in a front-rear direction, The electric pump according to claim 1 , wherein a center of gravity of the electric pump is farther from the pump unit than the grip portion is from the pump unit in the front-rear direction.

10. The motor unit is accommodated in the main body housing and further includes a control unit that drives the electric motor, 10. The electric pump according to claim 1, wherein when the electric pump is placed on a support surface and the electric pump is viewed in an up-down direction perpendicular to the support surface, the electric motor at least partially overlaps with the battery holding portion.

11. The electric pump according to claim 10, wherein when the electric pump is viewed in the up-down direction in a state in which the electric pump is placed on the placement surface, the electric motor at least partially overlaps with the control unit.

12. The electric motor rotates about a central axis extending in a front-rear direction, The electric pump according to claim 10 or 11, wherein a center of the battery holding portion and a center of the electric motor are disposed on a first plane in a left-right direction perpendicular to the front-rear direction and the up-down direction.

13. The electric pump according to claim 12 , wherein a center of the control unit is disposed on the first plane in the left-right direction.

14. The pump unit has a discharge port for discharging the water, the main body housing includes an upper wall in which the battery holding portion is disposed, and which is disposed below the discharge port when the electric pump is placed on a mounting surface; The electric pump according to claim 1 , wherein the upper wall is inclined with respect to the mounting surface when the electric pump is placed on the mounting surface.

15. The electric pump according to claim 1 , wherein the battery holding portion holds two of the battery packs.

Images