Electrical machine

Abstract

The present application provides a 36V electric machine capable of installing both 18V / 36V switching type battery pack and 18V battery pack. In the case of connecting 18V / 36V battery pack to 36V electric machine, the first switch (41, 42) is set to be off, the second switch is set to be on to connect the battery pack in series (36V output), in the case of connecting 18V battery pack (250) to 36V electric machine (1), the first switch (41, 42) is set to be on, the second switch is set to be off to set 18V output, thereby, the 36V electric machine can install 18V battery pack. Furthermore, the voltage of the installed battery pack is determined by microcomputer (51), the motor (5) is set to be star connection through switch (70, 75) at 36V, and is set to be delta connection at 18V.

Description

Technical Field

[0001] This invention relates to an electric motor that can be connected to multiple battery packs. Background Technology

[0002] A known electric motor includes a battery pack with a variable output voltage and an electric motor body to which the battery pack can be connected (Patent Document 1). In the battery pack of Patent Document 1, two battery cells are provided, along with two sets of positive terminals and negative terminals respectively connected to the two battery cells. The electric motor body includes a positive input terminal connected to one of the positive terminals, a negative input terminal connected to the other negative terminal, and a connecting element (short bar) connecting the other positive terminal to one of the negative terminals. The configuration is such that when the battery pack is connected to the electric motor body, the two battery cells are connected in series via the connecting element.

[0003] Patent Document 2 discloses an electric motor that can be connected to a battery pack with a different rated voltage and whose output voltage cannot be changed, within an electric motor body having a predetermined rated voltage. Patent Document 2 is configured such that a set of positive and negative terminals of the battery pack can be connected to a set of positive and negative input terminals of the electric motor body. Patent Document 3 discloses an electric tool including a voltage switching unit that switches the voltage supplied from the battery pack to the electric tool according to the magnitude of the load applied to the electric tool. Furthermore, Patent Document 4 discloses an electric tool that can selectively connect to a battery pack that can change the output voltage to high and low voltage, and a battery pack that can only output high voltage. Furthermore, Patent Document 5 discloses that, within the electric motor body, the wiring method of the motor coil can be changed according to an alternating current (AC) adapter or a direct current (DC) adapter connected as a power source.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2018 / 230337

[0007] Patent Document 2: International Publication No. 2020 / 066905

[0008] Patent Document 3: Japanese Patent Application Publication No. 2012-66333

[0009] Patent Document 4: International Publication No. 2019 / 031272

[0010] Patent Document 5: Japanese Patent Application Publication No. 2019-047605 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] The low / high voltage battery pack disclosed in Patent Document 1 can be installed in both conventional 18V and 36V electric machine bodies, thus offering excellent ease of use. However, while conventional 18V battery packs have nearly compatible terminal shapes, they are physically incompatible with 36V electric machine bodies. However, if existing 18V battery packs, whose output voltage cannot be changed, can be configured for use in 36V electric machine bodies, the convenience of new 36V electric machines can be improved. Furthermore, if battery packs with various nominal voltages can be selectively connected to the electric machine body, the electric machine body can be driven with high output and high efficiency depending on the connected battery pack, thereby improving workability.

[0013] This invention was made in view of the aforementioned background, and its object is to provide an electric machine that expands the compatibility between the battery pack and the electric machine body, thereby improving convenience. Another object of this invention is to provide an electric machine that improves workability.

[0014] Technical means to solve the problem

[0015] Representative features of the invention disclosed in this application are described below. According to one feature of the invention, an electric machine is capable of selectively connecting a first battery pack and a second battery pack. The first battery pack is capable of selectively outputting a high voltage or a low voltage, and the second battery pack is capable of outputting only the low voltage. The configuration is such that, when the first battery pack is connected to the electric machine, a high voltage is supplied to the electric machine from the first battery pack, and when the second battery pack is connected to the electric machine, a low voltage is supplied to the electric machine from the second battery pack. Furthermore, the electric machine has a voltage switching unit that switches the voltage supplied from the battery packs to the electric machine. When the first battery pack is connected to the electric machine, the voltage switching unit switches the voltage supplied from the first battery pack to the electric machine to a high voltage. Moreover, when the second battery pack is connected to the electric machine, the voltage switching unit maintains the voltage supplied from the second battery pack to the electric machine at a low voltage.

[0016] According to another feature of the present invention, the voltage switching unit of the electric motor is configured such that multiple cells in the first battery pack are connected to each other via the voltage switching unit, while multiple cells in the second battery pack are not connected to each other via the voltage switching unit. Furthermore, the voltage switching unit has a first switch unit configured to connect the multiple cells in the first battery pack to each other; the first switch unit is turned on when the first battery pack is connected to the electric motor, and turned off when the second battery pack is connected to the electric motor. Moreover, the electric motor has a motor including multiple coils; when the first battery pack is connected to the electric motor, the multiple coils are connected to each other in a first connection configuration; when the second battery pack is connected to the electric motor, the multiple coils are connected to each other in a second connection configuration different from the first connection configuration. Thus, the first connection configuration is suitable for high-voltage driving, and the second connection configuration is suitable for low-voltage driving; and when the same voltage is applied to the motor, the second connection configuration makes it easier for a large current to flow when comparing the first and second connection configurations.

[0017] According to another feature of the present invention, the first battery pack includes: first and second battery cells, a first positive terminal connected to the positive electrode of the first battery cell, a first negative terminal connected to the negative electrode of the first battery cell, a second positive terminal connected to the positive electrode of the second battery cell, and a second negative terminal connected to the negative electrode of the second battery cell; the second battery pack includes: a third battery cell included in at least one battery cell, a third positive terminal connected to the positive electrode of the third battery cell, and a third negative terminal connected to the negative electrode of the third battery cell. The electric motor includes: a positive input terminal that can be connected to the first and third positive terminals; a negative input terminal that can be connected to the second and third negative terminals; a first connecting terminal that can be connected to the first negative terminal; a second connecting terminal that can be connected to the second positive terminal; a connecting portion that connects the first and second connecting terminals to each other; and a load portion connected to the positive and negative input terminals. When a first battery pack is connected to the electric motor, the first positive terminal is connected to the positive input terminal, the second negative terminal is connected to the negative input terminal, the first negative terminal is connected to the first connecting terminal, and the second positive terminal is connected to the second connecting terminal. With the first and second battery cells connected in series via the connecting portion, power is supplied to the load portion from the first battery pack. Furthermore, when a second battery pack is connected to the electric motor, the third positive terminal is connected to the positive input terminal, the third negative terminal is connected to the negative input terminal, and power is supplied to the load portion from the second battery pack. The electric motor includes a control unit connected to a first switch, configured to switch the first switch on and off according to the connected battery pack.

[0018] According to another feature of the present invention, the electric motor includes: a second switching unit disposed between a first negative terminal and a ground wire; and a third switching unit disposed between a second positive terminal and a positive power line. A control unit blocks the second and third switching units when a first battery pack is connected, and connects the second and third switching units when a second battery pack is connected. Thus, an electric motor is capable of selectively connecting the first and second battery packs, wherein the first battery pack can selectively output a high voltage or a low voltage, and the second battery pack can output only a low voltage. The electric motor has a motor comprising multiple coils, and is configured such that, when the first battery pack is connected to the electric motor, the multiple coils are connected to each other in a first connection configuration, and when the second battery pack is connected to the electric motor, the multiple coils are connected to each other in a second connection configuration different from the first connection configuration. The first connection configuration is a star connection of the multiple coils, and the second connection configuration is a delta connection of the multiple coils.

[0019] The effects of the invention

[0020] According to the present invention, an electric motor with improved convenience can be provided. Furthermore, an electric motor with improved workability can be provided. Moreover, since the high-voltage electric motor can be appropriately operated using a low-voltage battery pack, an electric motor with improved convenience for the operator and thus improved workability can be provided. Furthermore, by automatically switching the characteristics of the work load (motor) contained in the high-voltage electric motor to star or delta connection before operation according to the type of battery pack installed, high output and high efficiency can be achieved depending on the type of battery pack. Attached Figure Description

[0021] Figure 1 This is an overall diagram of an electric motor system according to an embodiment of the present invention.

[0022] Figure 2 yes Figure 1 A three-dimensional view of the electric motor 1.

[0023] Figure 3 Viewed from another angle (bottom side) Figure 1 A perspective view of the main body of the electric motor 1.

[0024] Figure 4 This is a diagram showing the shape of the connection terminals of the electric motor 1 and the connection terminals of the battery packs 200 and 250.

[0025] Figure 5 This is a circuit diagram of the electric machine 1 in this embodiment when a low / high voltage battery pack 200 is installed.

[0026] Figure 6This is a circuit diagram of the electric machine 1 in this embodiment when a low-voltage battery pack 250 is installed.

[0027] Figure 7 This is a flowchart illustrating the voltage switching process of the electric motor 1 in this embodiment.

[0028] Figure 8 This is a circuit diagram of the electric machine 1A in the second embodiment of this example when a low / high voltage battery pack 200 is installed.

[0029] Figure 9 This is a circuit diagram of the electric motor 1A in the second embodiment of this example, when a low-voltage battery pack 250 is installed.

[0030] Figure 10 This is a circuit diagram of the electric machine 1B in the third embodiment of this example when a low / high voltage battery pack 200A is installed.

[0031] Figure 11 (A) is Figure 10 The diagram shows a top view of the battery pack mounting section 10B of the electric machine 1B. Figure 11 (B) is a top view of the low / high voltage battery pack 200A.

[0032] Figure 12 This is a circuit diagram of the electric motor 1B in the third embodiment of this example, when a low-voltage battery pack 250 is installed.

[0033] Figure 13 This is a diagram illustrating an example of switching control characteristics of a motor. Figure 13 (A) is a graph showing the relationship between motor speed and motor torque when the electronic advance angle is changed. Figure 13 (B) is a graph showing the relationship between motor speed and motor torque when the conduction angle is changed.

[0034] Explanation of symbols

[0035] 1, 1A, 1B: Electric machinery

[0036] 2: Shell

[0037] 2a: Main body

[0038] 2b: Handle

[0039] 2c: Saw cover

[0040] 3: Base

[0041] 3a: Resected portion

[0042] 4: Motor cover

[0043] 5: Motor

[0044] 5a: Rotor

[0045] 5b: Stator

[0046] 6: Trigger switch

[0047] 8: Saw blade

[0048] 9: Protective shield

[0049] 10, 10B: Battery pack mounting section

[0050] 11, 12: Track Department

[0051] 11a, 12a: concave part

[0052] 15: Termination section

[0053] 23: Press the tablet

[0054] 24: T-terminal

[0055] 25: V terminal

[0056] 26: LS terminal

[0057] 28: LD terminal

[0058] 30: Divider

[0059] 31: Positive input terminal

[0060] 32: Second connection terminal

[0061] 33: Negative input terminal

[0062] 34: First connecting terminal

[0063] 35: Power line (positive power line)

[0064] 36: Power line (grounding wire)

[0065] 37: Shortest route

[0066] 41: First Switch

[0067] 42: Second switch

[0068] 43: Third Switch

[0069] 44: Detector

[0070] 45: Capacitor

[0071] 46: Shunt resistor

[0072] 48: Position detection element

[0073] 50: Computational Unit

[0074] 51: Microcomputer

[0075] 52: Control signal circuit

[0076] 53: Rotational position detection circuit

[0077] 54: Speed ​​Detection Circuit

[0078] 55: Action Pattern Detection Circuit

[0079] 56: Action Mode Switch

[0080] 57: Current detection circuit

[0081] 58: Battery Pack Type Detection Circuit

[0082] 59: Voltage detection circuit

[0083] 60: Control power supply circuit

[0084] 61: Switch operation detection circuit

[0085] 62: Connect and maintain signal

[0086] 65: Inverter Circuit

[0087] 70: Fourth Switch

[0088] 71-73: Switch

[0089] 75: The Fifth Switch

[0090] 76-78: Switch

[0091] 101: Electric Machines

[0092] 110: Battery Pack Installation Department

[0093] 151: Electric Machine

[0094] 160: Battery pack installation section

[0095] 200, 200A: Battery pack (low / high voltage battery pack, first battery pack)

[0096] 201: Shell

[0097] 202: Lower section noodles

[0098] 203: Step Difference Part

[0099] 204: Upper Noodles

[0100] 205: Slot Group

[0101] 207: Stop section

[0102] 208a, 208b: Track groove

[0103] 209a, 209b: Locking button

[0104] 210: First cell unit

[0105] 220: Second cell unit

[0106] 221~228: Slot

[0107] 231: The First Positive Extreme

[0108] 231a, 231b: Arm

[0109] 232: The Second Positive Extreme

[0110] 232a, 232b: Arm

[0111] 241: First Negative Extreme Particle

[0112] 241a, 241b: Arm

[0113] 242: Second Negative Extreme

[0114] 242a, 242b: Arm

[0115] 243: Third Switch

[0116] 243a: Movable component

[0117] 247: Shortest Route

[0118] 250: Battery pack (low-voltage battery pack, second battery pack)

[0119] 251: Casing

[0120] 252: Lower section noodles

[0121] 253: Step Difference Part

[0122] 254: Upper Noodles

[0123] 255: Slot Group

[0124] 258a: Track groove

[0125] 259a: Locking button

[0126] 260: Third cell unit

[0127] 270: Fourth cell unit

[0128] 281: The Third Positive Extreme

[0129] 281a, 281b: Arm

[0130] 291: The Third Negative Extreme

[0131] 291a, 291b: Arm

[0132] Q1~Q6: Switching elements

[0133] Vcc: Reference voltage Detailed Implementation

[0134] Example 1

[0135] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. Furthermore, in the following drawings, the same symbols are used to label the same parts, and repeated descriptions are omitted. Also, in this specification, the directions of front-back, left-right, and up-down are described as shown in the drawings.

[0136] Figure 1 This is an overall diagram of an electric machine system according to an embodiment of the present invention. The electric machine system includes multiple electric machine bodies (1, 101, 151) and multiple battery packs (200, 250). Each electric machine body (1, 101, 151) is a machine that operates by installing any one of the corresponding battery packs (200, 250), and is a wireless machine that does not require AC power. The electric machine bodies (1, 101, 151) are classified according to the rated voltage of the battery packs used. Here, in addition to the known electric machine 101 configured to accept a high voltage supply of 36V and the known electric machine 151 configured to accept a low voltage supply of 18V, it also includes the electric machine 1 of this embodiment, which can operate at both 36V and 18V. Furthermore, in this specification, the state with the battery packs (200, 250) installed is referred to as "electric machine," and the body side with the battery packs (200, 250) removed is referred to as "electric machine body."

[0137] In the electric machine 1 equipped with a brushless motor, in order to realize that the electric machine 1 can operate at either 18V or 36V, it is configured to allow the insertion (installation) of both a battery pack 200 capable of low-voltage and high-voltage (18V and 36V) output and a conventional 18V battery pack 250 into the battery pack mounting section 10. Furthermore, the battery pack 200 is configured to output an identification signal indicating its own battery type, thereby enabling the control unit of the electric machine 1 to identify whether the installed battery pack supports dual voltages or other low-voltage battery packs.

[0138] The known electric machine 151 is a machine that operates at a rated voltage of 18V and is operated by installing a battery pack 250 for a rated voltage of 18V. The known electric machine 101 is a machine that operates at a rated voltage of 36V and is operated by using a battery pack that can output a rated voltage of 36V (in the applicant's commercial products, it is a battery pack 200 that can switch between 18V and 36V output).

[0139] Figure 1 In the text, "1", "101", and "151" represent examples of circular saws operated by either battery pack 200 or 250. However, the type of electric machine body is arbitrary and not limited to circular saws. Various machines can be used, such as impact screwdrivers, impact wrenches, screwdriver drills, disk grinders, hammer drills, blowers, cleaning machines, cutting machines, band saws, multi-tools, wire saws, saber saws, chainsaws, planers, pinning machines, tuckers, nailing machines, televisions, radios, speakers, fans, incubators, lamps, pressure washers, lawnmowers, etc.

[0140] The battery pack 200, capable of outputting either low voltage (18V) or high voltage (36V), as indicated by the solid arrows and the ○ symbol, can be installed in conventional electric machines 101 and 151 for operation, but it can also be installed in the electric machine 1 of this embodiment for operation. On the other hand, the low-voltage (18V) battery pack 250 can be installed in conventional electric machines 151 for operation, but as indicated by the × symbol, it cannot be installed in the high-voltage electric machine 101 (i.e., it cannot operate). However, the electric machine 1 of this embodiment has a battery pack mounting section 10 formed in such a way that the battery pack 250 can be installed, and it is configured to operate even at a low voltage of 18V.

[0141] Electric machine 1 is configured to operate primarily at 36V, but can also operate with an 18V power supply when a low-voltage (18V) battery pack 250 is installed. To enable this dual-voltage operation, the wiring configuration of the built-in motor or the motor's rotation control method can be changed (details of these changes will be provided later). Figure 5 (To be discussed later).

[0142] The battery pack 200 is formed by housing multiple (here, ten) battery cells within a synthetic resin casing 201. A lower surface 202 and an upper surface 204 are formed from the front to the rear of the upper surface of the battery pack 200, with a step portion 203 formed between the lower surface 202 and the upper surface 204. A group of slots 205 is formed from the step portion 203 to the front portion of the upper surface 204, and the group of slots 205 has eight slot-shaped cutouts. The connection terminals of the termination portions of the electric motors 1, 101, and 151 are inserted into the slots of the group of slots 205. On the upper side of the battery pack 200, track grooves 208a and 208b are formed for mounting battery pack mounting portions 10, 110, and 160 to electric machines 1, 101, and 151. Behind the track grooves 208a and 208b, locking buttons 209a and 209b constituting a locking mechanism are arranged. This locking mechanism is used to maintain or release the mounting state with the main body of electric machines 1, 101, and 151. The fifth and sixth slots from the right in the slot group 205 are partially recessed from the upper surface downwards. These recessed portions serve as stop portions 207 to prevent incorrect battery installation.

[0143] Battery pack 250 is formed by housing multiple (here, ten) battery cells within a synthetic resin casing 251. Battery pack 200 is designed to be compatible with the upper shape of 18V battery pack 250 on a base, so the upper half of battery pack 250 is identical (compatible) to battery pack 200 except for the non-blocking portion 207. From the front to the rear of the upper surface of battery pack 250, a lower section 252 and an upper section 254 are formed, with a step portion 253 between them. Furthermore, from the step portion 253 to the front portion of the upper section 254, a group of slots 255 is formed, which has eight slot-shaped cutouts. On the left and right sides sandwiching the group of slots 255, track grooves 258a and 258b and locking buttons 259a and 259b are formed.

[0144] like Figure 1 As shown by the solid lines, the battery pack 200 can be installed on electric machines 1, 101, and 151, and can supply 36V or 18V DC power to electric machines 1, 101, and 151. On the other hand, the battery pack 250 can be installed not only on the corresponding electric machine 151, but also on the electric machine 1 in this embodiment, and can supply 18V DC power to electric machines 1 and 151. However, the battery pack 250 cannot be installed on the battery pack mounting section 110 of the electric machine 101 for 36V applications.

[0145] In the electric machine 101 operating at a single 36V voltage, a convex baffle (not shown) corresponding to the stop portion 207 of the battery pack 200 is formed in the battery pack mounting portion 110. The baffle is shaped to extend downward from the upper wall near the connection terminal. When the battery pack 200 is installed, the baffle is positioned within the stop portion 207, thereby fitting the battery pack 200 into the termination portion. Since a baffle has always been formed in the termination portion of the electric machine 101, if a battery pack 250 without a corresponding recess (stop portion 207) is to be installed into the electric machine 101, the convex baffle formed in the termination portion of the electric machine 101 would interfere with the step portion 253, thus physically preventing the battery pack 250 from being installed into the electric machine 101. On the other hand, in the electric machine 1 of this embodiment, as a 36V electric machine, the termination portion with the conventionally provided convex baffle is omitted (see later description for details). Figure 3 Thus, the battery pack 250 can be installed in the battery pack mounting section 10 of the electric motor 1.

[0146] Electric machine 1 is a 36V electric machine that operates essentially at 36V. Here, a 36V DC power supply is provided from a battery pack 200 that supports multiple voltages, including 18V and 36V. On the other hand, when a battery pack 250 is installed in the battery pack mounting section 10 of electric machine 1, the supply voltage is 18V, and therefore it will operate at a lower voltage of 18V.

[0147] Electric machine 101 operates with a 36V voltage. Here, a battery pack 200 supporting multiple voltages (18V / 36V) is installed, from which 36V DC is supplied. Electric machine 151 operates with an 18V battery pack. Here, a battery pack 200 supporting multiple voltages (18V / 36V) is installed, from which 18V DC is supplied. Furthermore, a battery pack 250 supporting a single 18V voltage is installed, from which 18V DC is supplied.

[0148] Figure 1 Although not shown in the diagram, battery packs 200 and 250 can be charged using an 18V external charger (not shown) after being removed from the motor machine body (1, 101, 151). The above... Figure 1 In the illustrated electric machine system, the combination of low voltage and high voltage includes 18V and 36V. Furthermore, the terms "low voltage" and "high voltage" as used in this specification refer to the higher voltage side of any two rated voltages being called "high voltage" and the lower voltage side being called "low voltage." Therefore, the combination of low voltage / high voltage is not limited to 18V / 36V, but can also be other voltage groups.

[0149] Figure 2 yes Figure 1A perspective view of an electric circular saw 1. The electric circular saw 1 is shown as an example of one that operates essentially at 36V, but can also operate at 18V. The electric circular saw 1 comprises a housing 2 and a base 3 that rotatably supports the saw blade 8. The housing 2 comprises a body 2a, a handle 2b, and a saw cover 2c, and houses a motor 5 (not shown in the figure) and a control board, which serve as the load. The housing 2 is manufactured, for example, by integral molding of synthetic resin. A battery mounting section 10 is formed at the rear of the housing 2 and below the handle 2b, in which a dual-voltage battery pack 200 capable of low / high voltage output is installed. The saw blade 8 is mounted on the rotating shaft of the motor (not shown). The saw blade 8 is in the shape of a circular plate and rotates on the right side of the body 2a. The base 3 is, for example, a plate-shaped component made of metal such as aluminum, and has a cutting section 3a extending in the front-back direction through the vertical direction. The lower part of the saw blade 8 protrudes below the base 3 through the cutting section 3a. A movable protective cover 9 is provided circumferentially on the underside of the base 3 and on the outer periphery of the saw blade 8.

[0150] When cutting materials such as wooden boards by installing the battery pack 200 into the battery pack mounting part 10 of the electric motor 1, the operator grips the handle part 2b with one hand, presses the base 3 against the upper surface of the material, and pulls the trigger switch 6, thereby rotating the motor (not shown). While the saw blade 8 is rotating, the operator moves forward while the lower surface of the base 3 slides against the upper surface of the material. When the portion of the saw blade 8 that is lower than the lower surface of the base 3 presses against the material, the protective cover 9 moves relative to the side opposite to the direction of rotation, thereby cutting the material by the saw blade 8.

[0151] Figure 3 This is a perspective view of the main body of the electric machine 1 from another angle (bottom), showing the shape of the battery pack mounting section 10. The base 3 is omitted here for ease of observation. On the left side of the main body 2a, a motor cover 4 is provided, covering the motor 5 which is coaxially arranged with the rotation axis of the saw blade 8. The battery pack mounting section 10 is formed on the rear side of the motor cover 4. Two parallel track sections 11 and 12 are formed in the battery pack mounting section 10, and an end connector 15 is arranged on the inner part of the track sections 11 and 12. No protrusion (not shown) is formed in the end connector 15 to obstruct the installation of the 18V battery pack 250, thus allowing the 18V battery pack 250 to be installed.

[0152] Track portions 11 and 12 protrude inward from the left and right sidewall portions of the space housing the termination portion 15 towards the left and right center lines of the termination portion 15, forming track-like portions that continue from the rear to the front. Track portions 11 and 12 are formed symmetrically with respect to the vertical plane passing through the left and right center lines of the termination portion 15, and their long sides are parallel. When the battery pack 200 is installed in the termination portion 15, track portion 11 guides the track groove 208a of the battery pack 200, and track portion 12 guides the track groove 208b of the battery pack 200, thereby installing the battery pack 200 in the battery pack mounting portion 10. In this state, the locking claws of the battery pack 200 (not shown, which are movable protrusions that protrude outward from the bottom of the grooves of the track grooves 208a and 208b) are engaged with the locking grooves (recesses 11a and 12a) formed on the front end side of the track portions 11 and 12 by the force applied by the locking mechanism (not shown), thereby fixing the battery pack 200 in a way that it will not be disassembled from the end portion 15.

[0153] The termination portion 15 has four power terminals (31-34), four signal terminals (24-26, 28), and a separator plate 30. The four power terminals (31-34) and the four signal terminals (24-26, 28) are securely fixed by being cast into a synthetic resin base portion of the termination portion 15. The positive input terminal 31 and the second connection terminal 32 are inserted into the same slot. Figure 1 The slots 222 and 34 are arranged vertically. Furthermore, the negative input terminal 33 and the first connection terminal 34 are inserted into the same slot. Figure 1 The slots 227 are arranged vertically. Next, using Figure 4 To illustrate the shapes of the four electrical terminals (31-34) and the corresponding connection terminals on the battery pack 200 and 250 sides.

[0154] Figure 4 (A) is a partial perspective view showing the shapes of the positive terminals (231 and 232), negative terminals (241 and 242), and connection terminals (31-34) of the electric motor 1 of the battery pack 200 in this embodiment. As the positive terminal (positive output terminal) of the battery pack 200, a first positive terminal 231 with its arm on the upper side and a second positive terminal 232 with its arm on the lower side are provided. The first positive terminal 231 and the second positive terminal 232 are located in the same slot. Figure 1The second slot 222 from the right in the slot group 205, each has its feet fixed to the circuit board (not shown) in a front-to-back direction. Similarly, a second negative terminal 242 with its arm on the upper side and a first negative terminal 241 with its arm on the lower side are provided. The first negative terminal 241 and the second negative terminal 242 are located in the same slot. Figure 1 The second slot 227 from the left of the slot group 205, each of its feet is fixed to the circuit board (not shown) in a manner arranged in the front-back direction.

[0155] The first positive terminal 231 and the second positive terminal 232 each have arm assemblies (arms 231a and 231b, arms 232a and 232b) extending forward. Here, the first positive terminal 231 and the second positive terminal 232 are formed such that the arms 231a, 231b and arms 232a, 232b are spaced apart vertically, and their mating portions are approximately the same in the front-rear direction. The positive terminal pair including these positive terminals 231 and 232 is disposed in a slot 222 (see reference 231a) of the battery pack 200. Figure 1 The negative terminal pair has the same shape as the positive terminal pair, including a second negative terminal 242 and a first negative terminal 241. These negative terminal pairs (242, 241) are configured in a slot 226 (see reference) accessible from the battery pack 200. Figure 1 The space that can be reached. Additionally... Figure 4 Although not shown in the diagram, a charging positive terminal pair (not shown) is arranged to the right of the discharge positive terminal pair (first positive terminal 231 and second positive terminal 232). The shape of the charging positive terminal pair is the same as that of the first positive terminal 231 and the second positive terminal 232. The first positive terminal 231 and the second negative terminal 242 are common metal parts formed by stamping a metal sheet. Furthermore, the second positive terminal 232 and the first negative terminal 241 are common metal parts formed by stamping a metal sheet.

[0156] Inside the battery pack 200, there are cell units (210, 220) formed by connecting five lithium-ion battery cells in series. The rated voltage of each lithium-ion battery cell is 3.6V. Therefore, the total voltage of the first cell unit 210 is 18V (nominal value), and the total voltage of the second cell unit 220 is 18V (nominal value). The positive terminal of the first cell unit 210 is connected to the first positive terminal 231, and the negative terminal is connected to the first negative terminal 241. Similarly, the positive terminal of the second cell unit 220 is connected to the second positive terminal 232, and the negative terminal is connected to the second negative terminal 242.

[0157] The connection terminals on the motor side of the battery pack 200 are respectively provided with a positive input terminal 31 and a negative input terminal 33, and a first connection terminal 34 and a second connection terminal 32. These connection terminals (31-34) are fixed by a base portion of synthetic resin cast into the termination portion 15, and are connected to the power line 35, grounding wire 36, and shorting wire 37 (all described later) by welding through the connection portion having through holes. Figure 5 , Figure 6 The first connection terminal 34 and the second connection terminal 32 are connected using the third switch (SW) 43 described later (see reference). Figure 5 This short circuit is used to form a series connection between the first cell unit 210 and the second cell unit 220.

[0158] Figure 4 (B) is a partial perspective view showing the shapes of the positive terminal 281 and negative terminal 291 of the battery pack 250 and the connection terminals (31-34) of the electric motor 1 in this embodiment. The connection terminals (31-34) of the electric motor 1 and... Figure 4 (A) has the same shape. The battery pack 250 is for 18V and contains two battery cell units (260, 270). When the battery pack 250 is for 18V, it may contain only one battery cell unit, that is, only five lithium-ion battery cells. However, here, the third battery cell unit 260, which has five lithium-ion battery cells connected in series, and the fourth battery cell unit 270 are connected in parallel. Their positive terminal output is connected to the third positive terminal 281, and their negative terminal output is connected to the third negative terminal 291 to achieve a large capacity.

[0159] The arms 281a and 281b of the third positive terminal 281 have a large width in the vertical direction. The arms 231a and 231b of the first positive terminal 231 and the arms 232a and 232b of the second positive terminal 232 of the battery pack 200 are connected vertically, eliminating any gaps. Similarly, the arms 291a and 291b of the third negative terminal 291 also have a large width in the vertical direction. The arms 242a and 242b of the second negative terminal 242 of the battery pack 200 and the arms 241a and 241b of the first negative terminal 241 are connected vertically, eliminating any gaps. Regarding the terminal shapes of these third positive terminals 281 and 291, in... Figure 4 In the engagement state (as in (B)) (where the battery pack 250 is installed in the motor 1), the positive input terminal 31 and the second connection terminal 32 of the motor 1 are short-circuited by being simultaneously connected to the third positive terminal 281. Similarly, the negative input terminal 33 and the first connection terminal 34 of the motor 1 are short-circuited by being simultaneously connected to the third negative terminal 291.

[0160] Figure 5 This is a circuit diagram of the electric machine 1 in this embodiment with the battery pack 200 installed. The electric machine 1 in this embodiment includes an arithmetic unit (control unit) 50 containing a microcomputer 51. Although not shown, the microcomputer 51 is configured to include a central processing unit (CPU) for outputting drive signals based on processing programs and data, a read-only memory (ROM) for storing program or control data equivalent to the flowchart described later, a random access memory (RAM) for temporarily storing data, and a timer, etc., to perform rotation control of the motor 5 or to monitor the voltage and current of the installed battery packs 200 or 250. Figure 5 In this embodiment, a rechargeable battery pack 200 capable of outputting low or high voltage is used as a power source. The battery pack 200 is mounted on the battery pack mounting section 10 of the electric motor 1 (see reference 1). Figure 3 ).like Figure 3 As shown, on the positive side of the battery pack mounting section 10, there is a positive input terminal 31 and a second connection terminal 32, and on the negative side, there is a negative input terminal 33 and a first connection terminal 34. The output of the positive input terminal 31 is transmitted to the inverter circuit 65 via a power line (positive power line) 35, and the output of the negative input terminal 33 is transmitted to the inverter circuit 65 via a power line (ground wire) 36. A shunt resistor 46 is provided in the path of the power line 36. Furthermore, a capacitor 45 is provided between the power lines 35 and 36. The capacitor 45 is provided for smoothing and noise reduction.

[0161] In battery pack 200, such as Figure 4 As shown, two sets of battery cell units (210, 220) are housed. The output wiring of the first battery cell unit 210 is connected to the first positive terminal 231 and the first negative terminal 241, and the output wiring of the second battery cell unit 220 is connected to the second positive terminal 232 and the second negative terminal 242. By mounting the battery pack 200 to the battery pack mounting section 10 of the electric motor 1, the first positive terminal 231 is engaged with the positive input terminal 31, and the second positive terminal 232 is engaged with the second connection terminal 32. A first switch 41 is provided between the second connection terminal 32 and the power line 35. Furthermore, a second switch 42 is provided between the first connection terminal 34 and the power line 36. A short circuit 37 connecting the second connection terminal 32 and the first connection terminal 34 is provided, and a third switch 43 is provided for connecting or blocking this circuit.

[0162] Four power terminals (31-34) and the first to third switches (41-43) constitute a voltage switching unit for switching the voltage from the battery pack 200. The first to third switches (41-43) are constructed using known semiconductor switching elements such as mechanical relays, metal-oxide-semiconductor-field-effect transistor (MOSFET) relays, or FETs. Their opening and closing can be independently controlled according to control signals (wiring not shown) from the microcomputer 51 of the arithmetic unit 50. When using mechanical relays as the first to third switches (41-43), a double-pole single-throw relay switch with an a-contact can be used. Near the battery pack 200, a detector 44 is provided for detecting the type of battery pack installed. The detector 44 can distinguish between low / high voltage switching battery pack 200 and single-voltage (low voltage) battery pack 250 using either mechanical mechanisms or electrical signals and optical recognition technology. One method for easily performing this identification is by detecting the signal levels at the signal terminals of battery packs 200 and 250. For example, detector 44 transmits the signal from the T terminal of battery pack 200, used for battery identification signal output, to battery pack type detection circuit 58. After battery packs 200 and 250 are installed, battery pack type detection circuit 58 immediately reads the signal from the T terminals of battery packs 200 and 250, thereby enabling microcomputer 51 to identify which of battery packs 200 and 250 is installed.

[0163] The output of the battery pack 200 is transmitted to the inverter circuit 65 via power lines 35 and 36. The inverter circuit 65 includes multiple (six in this case) semiconductor switching elements Q1 to Q6, which are controlled by the arithmetic unit 50 according to the gate signals H1 to H6 supplied from the control signal circuit 52. The switching elements Q1 to Q6 use field-effect transistors (FETs), but insulated-gate bipolar transistors (IGBTs) can also be used. The output of the inverter circuit 65 is connected to one end of the U-phase, V-phase, and W-phase coils of the motor 5.

[0164] The control power supply circuit 60 is a DC power supply circuit that provides a stable reference voltage Vcc (e.g., 5V or 3.3V) for the operation of the arithmetic unit 50. The control power supply circuit 60 is connected to the second connection terminal 32 and the negative input terminal 33, and also receives the status signal of the trigger switch 6. The structure is such that when the battery pack 200 (or 250) is installed, the control power supply circuit 60 is supplied with battery voltage (18V DC). With this battery voltage applied, when the lever of the trigger switch 6 is turned on, the control power supply circuit 60 begins to supply power to the arithmetic unit 50. By using the status signal of the trigger switch 6 to activate the control power supply circuit 60, the microcomputer 51 of the arithmetic unit 50 does not start only when the battery pack 200 (or 250) is installed, thus suppressing power consumption when the electric machine is not in use. Furthermore, when the trigger switch 6 is turned on, power supply begins from the control power circuit 60 to the arithmetic unit 50, thus activating the arithmetic unit 50, which includes the microcomputer 51, and enabling control of turning the first to fifth switches (41-43, 70, 75) on or off. Additionally, even when the trigger switch 6 is turned off, power supply to the arithmetic unit 50 is maintained for a fixed period of time (e.g., five minutes) via an on / off sustain signal 62 from the arithmetic unit 50.

[0165] The microcomputer 51 controls the control signal circuit 52, thereby switching the gate signals H1 to H6 to the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 on or off. The motor 5 is a known brushless motor of the so-called internal rotor type, comprising: a rotor 5a, which is formed by embedding a pair of magnets (permanent magnets) including N and S poles; and a stator 5b, disposed on the outer periphery of the rotor 5a. The stator 5b has six teeth (not shown) extending from the cylindrical portion on the outer periphery inwards, and synthetic resin insulators (not shown) are provided on both sides of the rotation axis direction of the six teeth.

[0166] The stator core (not shown) contains, for example, a laminated structure of steel plates to guide strong magnetic field lines. Six coil elements are formed by repeatedly winding enameled wire around the outer periphery of the two insulators and the teeth they clamp. These six coil elements are connected in series in pairs to form three coils: the U-phase, V-phase, and W-phase. One end of each of the three coils (U-phase, V-phase, and W-phase) is connected to inverter circuit 65 (V-phase shown in the diagram). V V U V W The other end is connected to the fifth switch 75.

[0167] The fifth switch 75 is a group of switching switches used to short-circuit or open the other end of the three coils of phases U, V, and W, and includes three switches 76-78. The fifth switch 75 is constructed using known semiconductor switching elements such as mechanical relays, MOS FET relays, or FETs. The switching of the connection state is based on control signals from the microcomputer 51 (its wiring is not shown). When using mechanical relays, a double-pole single-throw relay switch with contact a can be used. The three switches 76-78 are linked and switch to on or off uniformly. Figure 5 In the connection state (switches 76-78 are in the ON state, switches 71-73 are in the OFF state), the ends of the U phase, V phase, and W phase are connected to form a "star connection" with a midpoint.

[0168] The fourth switch 70 is a switching group consisting of three switches 71 to 73, used to form a "delta connection" of three coils including phases U, V, and W. Switch 71 is configured in the wiring that short-circuits the inverter circuit 65 side of phase U to the midpoint side of phase W. Similarly, switch 72 is configured in the wiring that short-circuits the inverter circuit 65 side of phase V to the midpoint side of phase U, and switch 73 is configured in the wiring that short-circuits the inverter circuit 65 side of phase W to the midpoint side of phase V. The fourth switch 70 is constructed using known semiconductor switching elements such as mechanical relays, MOS FET relays, or FETs, and the switching of the connection state is performed based on control signals from microcomputer 51 (the wiring of which is not shown). When using mechanical relays, a double-pole single-throw relay switch with a contact or a contact b can be used. The three switches 71 to 73 are linked and switch to on or off uniformly, as described later. Figure 6 When the connection is in the following state (with switches 71-73 in the ON state and switches 76-78 in the OFF state), it becomes a "delta connection".

[0169] Near the rotor 5a of the motor 5, three position detection elements 48 are provided. The position detection elements 48 are arranged at 60° rotational angles on the inverter circuit 65. The rotational position detection circuit 53 is a circuit that detects the relative positions of the armature windings U, V, and W of the rotor 5a and stator 5b based on the output signals of the three position detection elements 48. The speed detection circuit 54 is a circuit that detects the speed of the motor 5 based on the number of detection signals from the rotational position detection circuit 53 counted per unit time.

[0170] The fourth switch 70 and the fifth switch 75 are only provided in the electric motor 1 that supports 18V / 36V. Figure 1The 36V electric motor 101 and the 18V electric motor 151 shown do not have this feature. In electric motors 101 and 151, the three coils of phases U, V, and W are directly soldered or connected to the inverter circuit board (not shown) provided on motor 5, thereby setting either "delta connection" or "star connection". That is, in electric motors 101 and 151, it is not possible to switch between "delta connection" and "star connection".

[0171] As described above, in the electric motor 1 operating with dual voltage, a fourth switch 70 and a fifth switch 75 are provided. Therefore, when the low / high voltage battery pack 200 is installed, before the motor 5 is started, all switches 71 to 73 of the fourth switch 70 are set to open, and all switches 76 to 78 of the fifth switch 75 are set to close, thereby enabling a star connection. Similarly, as described later... Figure 6 As shown, when an 18V battery pack 250 is installed, before the motor 5 starts running, all switches 71-73 of the fourth switch 70 are set to ON, and all switches 76-78 of the fifth switch 75 are set to OFF, thus setting the connection to a delta configuration (described later). Figure 6 (State).

[0172] The current detection circuit 57 measures the current flowing through the motor 5 by measuring the voltage across the shunt resistor 46 and outputs this measurement to the arithmetic unit 50. The voltage detection circuit 59 detects the voltage between the second connection terminal 32 and the negative input terminal 33 and outputs this voltage to the arithmetic unit 50. The switch operation detection circuit 61 detects whether the lever of the trigger switch 6 is moved and outputs a signal corresponding to the amount of lever movement to the arithmetic unit 50. The microcomputer 51 of the arithmetic unit 50 sets the duty cycle of the applied voltage, i.e., the pulse width modulation (PWM) signal, to the motor 5 in response to the amount of movement of the lever of the trigger switch 6. The operation mode switch 56 is a switch used to set the rotational speed of the motor 5 in stages. The operation mode detection circuit 55 detects the setting status of the switch and outputs this information to the arithmetic unit 50.

[0173] In the electric machine 1 described above, when the battery pack 200 is installed in the battery pack mounting section 10, an 18V output from the second cell unit 220 is supplied to the control power circuit 60. Therefore, when the trigger switch 6 is initially set to be on, the control power circuit 60 generates a reference voltage Vcc and supplies it to the arithmetic unit 50. When the reference voltage Vcc is supplied by the control power circuit 60, the microcomputer 51 starts up, thus determining whether the installed battery pack is an 18V / 36V battery pack 200 or an 18V battery pack 250, and sets the corresponding on / off state of the first switch 41 to the third switch 43. Subsequently, the on / off state of the fourth switch 70 and the fifth switch 75 is set. Figure 5In the circuit diagram, an 18V / 36V battery pack 200 is installed. The first switch 41 and the second switch 42 are set to open, and the third switch 43 is set to close. In this wiring state, a rated DC 36V is supplied between the power line 35 and the ground line 36. On the other hand, in order to configure the motor 5 as a star connection, switches 71 to 73 of the fourth switch 70 are set to open, and switches 76 to 78 of the fifth switch 75 are set to the connected state (closed).

[0174] Figure 6 This is a circuit diagram showing the installation of a low-voltage battery pack 250 in the battery pack mounting section 10 of the electric motor 1 in this embodiment. The circuit of the electric motor 1 is... Figure 5 They are completely identical, except that the connection states of the first to third switches 43 differ from those of the fourth switch 70 and the fifth switch 75. The installed battery pack 250 is rated at 18V. Figure 4 The terminal shapes are as shown in (B) for the third positive terminal 281 and the third negative terminal 291. When a low-voltage battery pack 250 is installed in the battery pack mounting section 10 of the electric motor 1, a rated 18V DC is output from the battery pack 250 to the positive input terminal 31 and the negative input terminal 33. At this time, the microcomputer 51 keeps the first switch 41 and the second switch 42 in the ON state and sets the third switch 43 to the OFF state. Next, the microcomputer 51 sets the wiring state of the motor 5 to delta connection by switching the fourth switch 70 and the fifth switch 75. That is, the microcomputer 51 keeps each switch 71 to 73 of the fourth switch 70 in the ON state and keeps each switch 76 to 78 of the fifth switch 75 in the OFF state.

[0175] Typically, when driving a motor 5, which is typically driven at 36V via a star connection, with 18V, it is advantageous to switch to a delta connection instead of a star connection. This is because, with a delta connection, even at a lower voltage, it is easier to increase the current, thereby increasing the speed of the motor 5 when generating the same torque.

[0176] Figure 7 This is a flowchart illustrating the voltage switching process of the electric motor 1 in this embodiment. Figure 7The series of processes shown can be executed by the microcomputer 51 in software via a program pre-stored in the arithmetic unit 50. In the initial state, i.e., when neither battery pack 200 nor 250 is installed, power cannot be supplied to the arithmetic unit 50, and therefore the microcomputer remains off. In this state, the first switch 41 to the third switch 43 are all in the off state (not conducting), and the fourth switch 70 and the fifth switch 75 are also all in the off state (U phase, V phase, and W phase are not connected) (step 81). Next, it is determined which of the battery packs 200 and 250 is installed; if not, it remains on standby until installation (step 82). When installation is performed in step 82, the control power circuit 60 (refer to...) is... Figure 5 , Figure 6 When the microcomputer 51 of the arithmetic unit 50 is powered by the supply of voltage, the control power circuit 60 starts to output the operating voltage Vcc to the arithmetic unit 50 when the trigger switch 6 is initially turned (steps 83 and 84). Therefore, the subsequent process after step 85 becomes executable.

[0177] Next, battery packs 200 and 250 will send the identification signal to detector 44 (see reference). Figure 5 , Figure 6 The detector 44 detects the received identification signal and sends it to the arithmetic unit 50 (step 86). Next, the microcomputer 51 determines whether the installed battery pack is a 18V / 36V low / high voltage battery pack 200 or a 18V single voltage battery pack 250 based on the identification signal (step 87).

[0178] In step 87, if it is determined that the installed battery pack is 18V / 36V, the microcomputer 51 sets the third switch 43 to ON (connect), and connects the second connection terminal 32 and the first connection terminal 34 via the short circuit 37. On the other hand, the first switch 41 and the second switch 42 remain in the OFF state (step 88). Figure 5 As shown in the circuit diagram, a 36V DC output is placed between the positive input terminal 31 and the negative input terminal 33. Next, the microcomputer 51 sets the wiring of the motor 5 for 36V operation (step 89). Here, an example of setting for 36V operation is as follows: Figure 5 The wiring of the motor 5 coil is configured as a star connection, as shown. That is, all switches 71 to 73 of the fourth switch 70 are set to open, and all switches 76 to 78 of the fifth switch 75 are set to close. Once this wiring is completed, the microcomputer 51 starts the motor 5 and begins the operation of the electric machine (step 90).

[0179] In step 87, if it is determined that the installed battery pack 250 is 18V, the microcomputer 51 sets the third switch 43 to open (not connected), blocking the path of the short circuit 37, and keeps the first switch 41 and the second switch 42 in the on state (step 91). This state is... Figure 6 As shown in the circuit diagram, 18V DC is output between the positive input terminal 31 and the negative input terminal 33. Next, the microcomputer 51 sets the wiring of the motor 5 for 18V operation (step 92). Here, an example of setting for 18V operation is as follows: Figure 6 The wiring of the motor 5 coil is configured as a delta connection, as shown. That is, all switches 71 to 73 of the fourth switch 70 are set to ON, and all switches 76 to 78 of the fifth switch 75 are set to OFF. Once this wiring is completed, the microcomputer 51 starts the motor 5 and begins the operation of the electric machine (step 90).

[0180] Once the operation in step 90 is completed and the trigger switch 6 is restored, the motor 5 stops, but until the microcomputer 51 is turned off, it maintains the state of the first switch 41 to the third switch 43 set in step 88 or 91, and maintains the state of the fourth switch 70 and the fifth switch 75 set in step 89 or 92.

[0181] According to this embodiment, the arithmetic unit 50 of the electric machine 1 determines the type of the installed battery pack (whether it is a low / high voltage battery pack 200 or a single-voltage battery pack 250) and performs wiring settings for the input terminals (31, 33) and connection terminals (32, 34) adapted to the type of installed battery pack. Therefore, even in an electric machine with a 36V termination section, an 18V battery pack can be installed. Furthermore, the connection configuration of the motor 5's coil (star or delta connection) is switched according to the voltage of the installed battery pack 200 or 250. Therefore, even when a low-voltage battery pack 250 is installed, the electric machine 1 can be used without feeling out of place. Furthermore, for the user, the battery packs 200 and 250 can be used efficiently and freely, thus improving ease of use.

[0182] Furthermore, according to this embodiment, the motor 5, which includes multiple coils, is configured such that, when the first battery pack (250) is connected to the electric motor 1, the multiple coils are connected to each other in a first connection configuration (e.g., star connection), and when the second battery pack (200) is connected to the electric motor, the multiple coils are connected to each other in a second connection configuration (e.g., delta connection) different from the first connection configuration. Therefore, an efficient driving method can be selected based on the installed battery pack. Moreover, it can compensate for the situation where, without switching the connection configuration, only about half the speed of 36V can be achieved. Furthermore, even with 18V, the same speed and torque as with 36V can be ensured. The speed at the same torque can be increased.

[0183] Example 2

[0184] Next, use Figure 8 as well as Figure 9 The second embodiment of the invention of this application will be described below. Figure 8 This is a circuit diagram of the battery pack mounting section 10 of the electric machine 1A in the second embodiment of this invention, when a low / high voltage battery pack 200 is mounted. Figure 5 , Figure 6 The difference in the first embodiment shown is that the first switch 41 is omitted from the battery pack mounting section 10 of the electric machine 1A (see reference). Figure 5 ) and the second switch 42 (refer to) Figure 5 That is, in the first embodiment, the first switch 41 and the second switch 42 (refer to...) Figure 5 The first connection terminal 34 is not directly connected to the grounding wire 36 because part of it is not wired. Therefore, the second connection terminal 32 is not directly connected to the power line 35, and the first connection terminal 34 is not directly connected to the grounding wire 36. Except for the absence of the first switch 41 and the second switch 42 (see reference...). Figure 5 The other components are the same as in the first embodiment. The method for switching between star and delta connections for motor 5 is also controlled in the same way using the fourth switch 70 and the fifth switch 75. When a low / high voltage battery pack 200 is installed in the battery pack mounting section 10 of the electric motor 1A, the third switch 43 is turned on and the short circuit 37 is connected, thereby outputting 36V DC between the positive input terminal 31 and the negative input terminal 33. At this time, all switches 71 to 73 of the fourth switch 70 are turned off, and all switches 76 to 78 of the fifth switch 75 are turned on, so that motor 5 is connected in a star configuration.

[0185] Figure 9 This is a circuit diagram of the battery pack mounting section 10 of the electric motor 1A in the second embodiment of this invention when a low-voltage battery pack 250 is installed. When installing the low-voltage battery pack 250, the third positive terminal 281 and the third negative terminal 291 (both refer to...) Figure 4In the shape of (B), the positive input terminal 31 and the second connection terminal 32 are short-circuited, and the negative input terminal 33 and the first connection terminal 34 are short-circuited. Furthermore, if the microcomputer 51 determines, based on the output of the battery pack type detection circuit 58, that the installed battery pack 250 is 18V, it keeps the third switch 43 in the off state. Then, the microcomputer 51 sets all switches 71-73 of the fourth switch 70 to the on state and sets all switches 76-78 of the fifth switch 75 to the off state, so that the motor 5 is connected in a delta configuration.

[0186] The voltage switching process of the electric motor 1A in the second embodiment is the same as... Figure 7 The flowcharts shown are largely the same. The only difference is that the control of the first switch 41 and the second switch 42 is not required in steps 88 and 91. In the second embodiment, the first switch 41 and the second switch 42 can be omitted, thus reducing the number of switches disposed in the housing 2 of the electric machine 1A and suppressing the enlargement of the housing 2.

[0187] Example 3

[0188] Figure 10 This is a circuit diagram of the battery pack mounting section 10 of the electric machine 1B in the third embodiment of this invention, when a low / high voltage battery pack 200A is installed. The 18V / 36V battery pack 200A and... Figure 5 Similarly, the low / high voltage battery pack 200 shown also has a first positive terminal 231 with its arm on the upper side and a second positive terminal 232 with its arm on the lower side as the positive terminal of the battery pack 200A. Likewise, it has a second negative terminal 242 with its arm on the upper side and a first negative terminal 241 with its arm on the lower side. In the corresponding electric motor 1B, a positive input terminal 31, a negative input terminal 33, and a second connection terminal 32 are provided. However, the equivalent of... Figure 5 The terminal of the first connection terminal 34 shown.

[0189] In the third embodiment, a shorting line 247 is provided within the frame of the 18V / 36V battery pack 200A, and a third switch 243 is provided along the path of the shorting line 247. The third switch 243 is located from the housing 201 (see reference). Figure 2 The external surface of the switch allows the movable contact to move physically, controlling the connection or disconnection. Here, a pressing piece 23 (located on the side of the battery pack mounting section 10 of the electric machine 1B) is used. Figure 11 (To be described later) The movable piece 243a of the third switch 243 is oriented in the direction indicated by arrow 235. Figure 11(As described later) Applying force, the third switch 243 becomes closed. Furthermore, when battery pack 200A is installed, the microcomputer 51 can determine via detector 44 that battery pack 200A is a 36V output model. Therefore, all fourth switches 70 are set to open, and all fifth switches 75 are set to closed, thus configuring the motor 5's coils in a star connection. Next, using... Figure 11 The shapes of the pressing piece 23 and the third switch 243 of the battery pack mounting part 10 provided in the electric motor 1B will be explained.

[0190] Figure 11 (A) is Figure 10 The diagram shows a bottom view of the battery pack mounting section 10B of the electric machine 1B. In the battery pack mounting section 10B, [a series of components] are arranged at vertically spaced intervals. Figure 4 The positive input terminal 31 and the second connection terminal 32 (appear to overlap in the figure) are shown, and the negative input terminal 33 and the first connection terminal 34 (appear to overlap in the figure) are arranged vertically at a distance. Between the first connection terminal 34 and the second connection terminal 32, there are communication terminals 24 (T), 25 (V), and 26 (LS), and next to the first connection terminal 34, there is an LD terminal 28. Between the second connection terminal 32 and the T terminal 24, there is a pressing tab 23 for pressing the third switch 243. The pressing tab 23 is located at the position where... Figure 11 In slot 223 of (B), conventional 18V battery packs or conventional 18V / 36V battery packs do not have connection terminals, thus providing reserved space. Therefore, in the third embodiment, a pressing piece 23 made of a non-conductive material such as synthetic resin is provided in the reserved space, and when the battery pack 200 is installed in the battery pack mounting part 10B, the third switch 243 disposed in the corresponding slot 223 is pressed.

[0191] Figure 11 (B) is a schematic diagram of the upper surface of the low / high voltage battery pack 200A. The shape of the battery pack 200A differs from that of the low / high voltage battery pack 200 in that the third switch 243 is disposed within the slot 223. In the slot group 205 of the battery pack 200A, eight slots 221 to 228 are arranged from the right. Slot 222 is for the positive electrode, and its internal space contains… Figure 4 The first positive terminal 231 and the second positive terminal 232 are shown. The slot 227 is used for the negative terminal, and its internal space is configured with... Figure 4 The first negative terminal 241 and the second negative terminal 242 are shown. When installing the battery pack 200A... Figure 11When the battery pack mounting portion 10B shown in (A) is moved, the positive input terminal 31 and the second connection terminal 32 are inserted into the slot 222, and the first positive terminal 231 and the second positive terminal 232 are engaged. Furthermore, the negative input terminal 33 and the first connection terminal 34 are inserted into the slot 227, and the second negative terminal 242 is engaged with the first negative terminal 241. Additionally, communication terminals 24-26 and 28 are also inserted into slots 224-226 and 228, respectively, and engaged with the communication terminals on the battery pack 200A side.

[0192] The pressing piece 23 of the battery pack mounting portion 10B of the electric machine 1B is inserted into the slot 223, pressing the movable member 243a of the third switch 243 and moving it, thereby switching the third switch 243 from the off state to the on state. That is, the protrusion (pressing piece 23) of the battery pack mounting portion 10B of the electric machine 1B operates the third switch 243 located in the empty slot 223 on the battery pack 200A side, thus automatically operating the third switch 243. Therefore, when the dual-voltage battery pack 200A for 18V / 36V is installed, the third switch 243 is forcibly turned on, i.e., becomes... Figure 10 The connection state is shown in the circuit diagram. When the battery pack 200A is removed from the battery pack mounting part 10B of the electric motor 1B, the pressed pressing piece 23 leaves the third switch 243, so the movable piece (movable member 243a) of the third switch 243 returns to its original position (initial position) by the action of a spring (not shown), thereby making the third switch 243 open.

[0193] Figure 12 This is a circuit diagram of the electric motor 1B in the third embodiment of this invention when an 18V battery pack 250 is installed in the battery pack mounting section 10B. The external shape of the termination or track section of the 18V battery pack 250 is similar to... Figure 11 The appearance of the battery pack 200A shown in (B) is the same (compatible). Figure 4 The third positive terminal 281 shown in (B) is configured in an equivalent position. Figure 11 The position of slot 222 in (B), Figure 4 The third negative extremum 291 shown in (B) is configured in an equivalent position. Figure 11 The position of slot 227 of (B). On the other hand, no equivalent to the third switch 243 (see reference) is provided inside the 18V battery pack 250. Figure 10 The switch is equivalent to Figure 11The internal space of the slot 223 in (B) is empty. Therefore, even if the battery pack 250 is installed in the battery pack mounting part 10B of the electric machine 1B, as long as the non-conductive pressing piece 23 is inserted into the empty slot 223 as shown by arrow 235, the circuit structure on the battery pack 250 side does not need to be changed.

[0194] The battery pack 250 has a third positive terminal 281 and a third negative terminal 291. The third positive terminal 281 is engaged with the positive input terminal 31 and the second connection terminal 32, and the third negative terminal 291 is engaged with the negative input terminal 33. As a result, as... Figure 12 As shown, 18V DC is output between the power line 35 and the grounding line 36. Moreover, when the battery pack 250 is installed, the microcomputer 51 can determine by the detector 44 that the battery pack 250 is a model that can output 18V, so the fourth switch 70 is all turned on and the fifth switch 75 is all turned off, so that the coil of the motor 5 is connected in a delta configuration.

[0195] In the third embodiment, a short circuit 247 for connecting two battery cell units 210 and 220 in series is disposed inside the battery pack 200A. The battery pack mounting section 10B of the electric machine 1B is provided with an operating member (pressing piece 23) for operating the third switch 243 disposed inside the battery pack 200A. Therefore, by simply mounting the battery pack 200A onto the battery pack mounting section 10B of the electric machine 1B equipped with the pressing piece 23, the output of the battery pack 200A can be automatically switched to the high output side.

[0196] In the first to third embodiments described above, when a high-voltage (36V) battery pack is installed in the battery pack mounting sections 10 and 10B, the motor 5 is configured with a star connection, and when a low-voltage (18V) battery pack is installed, the motor 5 is configured with a delta connection. However, other methods may be considered for switching the control of the motor 5 between rotation control most suitable for high-voltage drive and rotation control most suitable for low-voltage drive.

[0197] Figure 13 This is a diagram illustrating an example of switching control characteristics of a motor. Figure 13Figure (A) shows the relationship between motor speed and motor torque when the electronic advance angle is changed. Here, the electronic advance angle will be explained. The moment when the signal output from the position detection element (Hall Integrated Circuit, IC) 48 to the arithmetic unit 50 (microcomputer 51) switches from on to off, or from off to on, the switching of the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 is called an electronic advance angle of 0 degrees. The moment when the rotation angle of the rotor 5a is 15 degrees ahead of this moment, the switching of the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 is called an electronic advance angle of 30 degrees (15 degrees × 2 (for a four-pole rotor)). In the figure, the vertical axis represents the speed of the motor 5 (unit: min). -1 The horizontal axis represents the torque generated by motor 5 (unit: N·m). Characteristic 93 describes the motor speed and torque characteristics when motor 5 is driven with 36V and an electronic advance angle of 30 degrees in an electric motor 1 supporting 18V / 36V. It exhibits the characteristic that the motor speed decreases linearly as the motor torque increases. When the same motor 5 is driven with 18V power, characteristic 94 (shown by the dashed line) is observed, resulting in a decrease in both motor speed and torque. Therefore, by switching the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 on and off before the rotor 5a's rotation angle reaches 30 degrees relative to the electronic advance angle of 0 degrees (electronic advance angle 30 × 2 (for a 4-pole rotor) = 60 degrees), even with 18V power, the electronic advance angle is changed from 30 degrees to 60 degrees. This allows for a significant increase in motor speed in the low torque region, as shown by characteristic 95. Thus, when the 18V battery pack 250 is installed on the electric motor 1, the rotational characteristics can be approached when operating at 36V by increasing the electronic advance angle.

[0198] Figure 13(B) is a graph showing the relationship between motor speed and motor torque when the conduction angle is changed. Here, the conduction angle is explained. Since the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 are switched on and off according to the position of rotor 5a (output of position detection element 48), the current flowing through each stator coil (U phase, V phase, W phase) also changes with the on / off state of energization or the direction of current flow (positive direction, negative direction). A 120-degree energization means that before rotor 5a rotates 60 degrees (60 degrees × 2 (in the case of a four-pole rotor) = 120 degrees in electronic angles), the on / off state of energization of each stator coil and the direction of current flow do not change when switching on and off. Characteristic 96 describes the characteristics of motor speed and motor torque when the motor 5 is driven at 36V and the conduction angle is 120 degrees in a 18V / 36V electric motor 1. The motor exhibits the characteristic that its speed decreases linearly as the motor torque increases. In motor 5 with this characteristic, when the same motor 5 is driven with 18V power, characteristic 97 (shown by the dashed line) occurs, resulting in a decrease in both motor speed and torque. Therefore, before the rotor 5a rotates 90 degrees (90 degrees × 2 (in the case of a four-pole rotor) = 180 degrees in electronic angle), the semiconductor switching elements Q1 to Q6 of the inverter circuit 65 are switched on and off in a manner that does not change the energization of each stator coil or the direction of current flow. Even with 18V power, the conduction angle is changed from 120 degrees to 180 degrees, thus significantly increasing the motor speed in the low-torque region, as shown by characteristic 98. In this way, when the 18V battery pack 250 is installed in the electric motor 1, by increasing the conduction angle, the rotational characteristics approaching those of 36V operation can be achieved.

[0199] The present invention has been described above based on the embodiments, but the present invention is not limited to the embodiments described, and various modifications can be made without departing from its spirit.

Claims

1. An electric motor comprising an electric motor body capable of selectively connecting a first battery pack and a second battery pack, the first battery pack being capable of selectively outputting a high voltage or a low voltage, and the second battery pack being capable of outputting only the low voltage, characterized in that... The electric motor body has a voltage switching unit that switches the voltage supplied to the electric motor body from the first battery pack and the second battery pack. The configuration is such that, when the first battery pack is connected to the electric motor body, the high voltage is supplied from the first battery pack to the electric motor body, and when the second battery pack is connected to the electric motor body, the low voltage is supplied from the second battery pack to the electric motor body. The voltage switching unit is configured to switch the voltage supplied from the first battery pack to the electric motor body to the high voltage when the first battery pack is connected to the electric motor body.

2. The electric motor according to claim 1, characterized in that, The voltage switching unit is configured to maintain the voltage supplied from the second battery pack to the electric motor body at the low voltage when the second battery pack is connected to the electric motor body.

3. The electric motor according to claim 2, characterized in that, The voltage switching unit is configured such that multiple cells in the first battery pack are connected to each other via the voltage switching unit, while multiple cells in the second battery pack are not connected to each other via the voltage switching unit.

4. The electric motor according to claim 3, characterized in that, The voltage switching unit has a first switching unit, which is configured to connect multiple cells contained in the first battery pack to each other. The first switch is set to be turned on when the first battery pack is connected to the electric motor body, and set to be turned off when the second battery pack is connected to the electric motor body.

5. The electric machine according to any one of claims 1 to 4, characterized in that, The electric motor body has a motor including multiple coils. When the first battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a first connection configuration. When the second battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a second connection configuration different from the first connection configuration.

6. The electric motor according to claim 5, characterized in that, The configuration is such that the first connection configuration is suitable for high-voltage driving, and the second connection configuration is suitable for low-voltage driving.

7. The electric motor according to claim 5, characterized in that, The configuration is such that, when the same voltage is applied to the motor, if the first connection configuration is compared with the second connection configuration, the second connection configuration makes it easier for a large current to flow.

8. The electric machine according to any one of claims 1 to 4, characterized in that, The first battery pack includes: a first battery cell unit and a second battery cell unit, a first positive terminal connected to the positive electrode of the first battery cell unit, a first negative terminal connected to the negative electrode of the first battery cell unit, a second positive terminal connected to the positive electrode of the second battery cell unit, and a second negative terminal connected to the negative electrode of the second battery cell unit. The second battery pack includes: a third battery cell contained in at least one battery cell, a third positive terminal connected to the positive electrode of the third battery cell, and a third negative terminal connected to the negative electrode of the third battery cell. The electric motor body includes: a positive input terminal that can be connected to the first positive terminal and the third positive terminal; a negative input terminal that can be connected to the second negative terminal and the third negative terminal; a first connecting terminal that can be connected to the first negative terminal; a second connecting terminal that can be connected to the second positive terminal; a connecting portion that connects the first connecting terminal and the second connecting terminal to each other; and a load portion that is connected to the positive input terminal and the negative input terminal. With the first battery pack connected to the motor body, the first positive terminal is connected to the positive input terminal, the second negative terminal is connected to the negative input terminal, the first negative terminal is connected to the first connection terminal, and the second positive terminal is connected to the second connection terminal. With the first and second battery cells connected in series via the connection portion, power is supplied to the load from the first battery pack. When the second battery pack is connected to the motor body, the third positive terminal is connected to the positive input terminal, and the third negative terminal is connected to the negative input terminal, so that power is supplied to the load from the second battery pack.

9. The electric motor according to claim 4, characterized in that... include: The control unit is connected to the first switch unit. The control unit is configured to switch the first switch unit on and off according to the connected battery pack.

10. The electric machine according to any one of claims 1 to 4, characterized in that... include: The second switch is located between the first negative terminal and the grounding wire; as well as The third switch is located between the second positive terminal and the positive power line. The control unit blocks the second and third switch units when the first battery pack is connected, and connects the second and third switch units when the second battery pack is connected.

11. The electric machine according to any one of claims 1 to 4, characterized in that... include: At least one of the first battery pack and the second battery pack.

12. An electric machine comprising an electric machine body capable of selectively connecting a first battery pack and a second battery pack, the first battery pack being capable of selectively outputting a high voltage or a low voltage, and the second battery pack being capable of outputting only the low voltage, characterized in that... A motor having multiple coils, and The configuration is such that, when the first battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a first connection configuration, and when the second battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a second connection configuration different from the first connection configuration.

13. An electric machine comprising an electric machine body, the electric machine body being selectively connectable to a first battery pack and a second battery pack different from the first battery pack, characterized in that, A motor having multiple coils, and The configuration is such that, when the first battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a first connection configuration, and when the second battery pack is connected to the electric motor body, the plurality of coils are connected to each other in a second connection configuration different from the first connection configuration.

14. The electric machine according to claim 12 or 13, characterized in that, The first connection configuration is a star connection of the plurality of coils, and the second connection configuration is a delta connection of the plurality of coils.

15. The electric motor according to claim 12 or 13, characterized in that... include: At least one of the first battery pack and the second battery pack.

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