Stator having a plurality of connections

Abstract

The invention relates to a stator for an electric motor, in particular as a drive for a power tool, comprising a laminated stator core having at least a first and a second pole tooth, each for receiving and holding at least one coil wire, and also at least a first and a second contact rail for electrically contacting one coil wire each. Each contact rail comprises at least a first and a second connection element, wherein the first connection element is positioned in a first plane and the second connection element is positioned in a second plane.

Description

[0001] Stator with multiple connections

[0002] The present invention relates to a stator for an electric motor, in particular as a drive for a machine tool, comprising a stator laminated core with at least one first and second pole tooth for respectively receiving and holding at least one coil wire and at least one first and second contact rail for electrically contacting a respective coil wire.

[0003] Furthermore, the present invention relates to an electric motor with a stator.

[0004] Furthermore, the present invention relates to a machine tool with a stator.

[0005] Electric motors, in particular as drives for machine tools, are known from the prior art, which essentially comprise a stator and a rotor rotatable relative to the stator in order to generate a torque.

[0006] Electric motors, such as brushless DC motors, are typically located inside a machine tool housing. The installation space inside a machine tool housing is often very limited, leaving little room for advantageous or desired positioning of the components (and especially the electric motor).

[0007] Furthermore, machine tools can be designed in a wide variety of configurations, such as hammer drills, chipping hammers, grinders, saws, lamps, or the like. The installation space inside these different machine tools can also vary greatly. An advantageous or desired positioning or arrangement of a standardized electric motor in all these different machine tool housings can lead to significant modifications or design adjustments either to the electric motor and / or to the corresponding machine tool housings.

[0008] It is therefore an object of the present invention to solve the problem described above.

[0009] The object is achieved by the subject matter of independent patent claims 1, 4 and 5. Further advantageous embodiments of the subject matter according to the invention are contained in the corresponding dependent patent claims. i The object is achieved in particular by a stator for an electric motor, in particular as a drive for a machine tool, comprising a stator laminated core with at least one first and second pole tooth for respectively receiving and holding at least one coil wire, as well as at least one first and second contact rail for electrically contacting each coil wire.

[0010] According to the invention, each contact rail contains at least a first and a second connection element, wherein the first connection element is positioned in a first plane and the second connection element is positioned in a second plane.

[0011] According to an advantageous embodiment, it may be possible for the first and second planes to be designed as two intersecting planes.

[0012] According to a further advantageous embodiment, it may be possible for the first and second planes to be arranged substantially orthogonally to one another.

[0013] According to a further advantageous embodiment, it may be possible for the first and / or second connection element to be designed for a material-locking, form-locking and / or force-locking connection to a power cable.

[0014] According to a further advantageous embodiment, it may be possible for the first and / or second connection element to be designed for welding, soldering, screwing and / or plugging onto a power cable.

[0015] According to a further advantageous embodiment, it may be possible for the first and / or second connection element to be designed as a socket.

[0016] Furthermore, the task is solved by an electric motor with a stator.

[0017] Furthermore, the task is solved by a machine tool with a stator.

[0018] Further advantages will become apparent from the following description of the figures. The figures illustrate various embodiments of the present invention.

[0019] The figures, the description, and the claims contain numerous features in combination. The skilled person will expediently consider the features individually and combine them into further meaningful combinations.

[0020] They show:

[0021] Figure 1 is a schematic side view of a machine tool according to the invention according to an exemplary embodiment;

[0022] Figure 2 is a front view of an electric motor with a stator and rotor;

[0023] Figure 3 is a perspective view of the stator according to an exemplary

[0024] embodiment;

[0025] Figure 4 is a perspective view of a contact rail with a first and second connection element according to an exemplary embodiment;

[0026] Figure 5 is a further perspective view of the stator with a number of power cables according to a first exemplary embodiment;

[0027] Figure 6 is a plan view of the stator with a number of power cables according to a second exemplary embodiment; and

[0028] Figure ? a further plan view of the stator with a number of power cables according to a third exemplary embodiment.

[0029] Examples of implementation:

[0030] Figure 1 shows a machine tool 1 according to an exemplary embodiment. The machine tool 1 is designed as a battery-powered drill.

[0031] According to an alternative embodiment, the machine tool can also be designed in the form of a saw, a grinder, a hammer drill or the like.

[0032] The machine tool 1 designed as a drilling machine essentially contains a housing 2, a handle s, a tool holder 4 and a power supply 5.

[0033] The housing 2 has a front end 2a, a rear end 2b, an upper end 2c and a lower end 2d.

[0034] The tool holder 4 is positioned at the front end 2a of the housing 2. The tool holder 4 serves to receive and hold a tool. The tool is not shown in the figures.

[0035] In the present embodiment, the tool can be designed in the form of a drill. A first end 3a of the handle 3 is positioned at the lower end 2d of the housing 2. An interface 6 is provided at the second end 3b of the handle 3.

[0036] As shown in Figure 1, the handle 3 has an activation switch 8 with which the machine tool 1 can be set to an activation state or a deactivation state.

[0037] The power supply 5 can be releasably attached to the interface 6. In the present embodiment, the power supply 5 is designed in the form of a rechargeable battery. The power supply 5 serves to supply the machine tool with electrical energy.

[0038] According to an alternative embodiment, the power supply 5 can also be configured as a cable for connecting the machine tool 1 to a mains power source (socket). The power supply 5 configured as a cable is not shown in the figures.

[0039] Inside the housing 2 there is essentially positioned an electric motor 9 as a drive, a transmission device 10, a drive shaft 11 and a control device 12.

[0040] The electric motor 9, the gear mechanism 10, the drive shaft 11, and the tool holder 4 are arranged relative to one another inside the housing 2 such that a torque generated in the electric motor 9 can be transmitted to the gear mechanism 10, the drive shaft 11, and ultimately to the tool holder 4 or to the tool. The control device 12 is connected to the activation switch 8, the battery interface 6, and the electric motor 9 via corresponding lines L.

[0041] The power supply 5, designed as a rechargeable battery, can be detachably connected to the machine tool 1 to supply the machine tool 1 with electrical energy. The rechargeable battery 5 essentially contains a battery housing 20, a number of energy storage cells 13, a battery interface 14, and a control device 15.

[0042] The energy storage cells 13 can also be referred to as battery cells and are arranged inside the battery housing 20.

[0043] The battery housing 20 essentially contains a cover element 20a, four side walls 20b and a base element 20c.

[0044] The battery interface 14 is arranged on the outside of the cover element 20a and serves for the electrical or electronic as well as mechanical connection of the battery 5 to the machine tool 1 or a charging device.

[0045] The charging device is used to charge the accumulator 5 with electrical energy and is not shown in the figures.

[0046] For electrical or electronic connection, the battery interface 14 has a positive contact, a negative contact, and a communication contact. The positive and negative contacts serve to create an electrical circuit when the battery 5 is connected to a machine tool 1 or a charging device. The communication contact serves to send and receive data and information in the form of electrical signals.

[0047] Alternatively or additionally, the accumulator 5 may also contain radio communication (e.g. Bluetooth) or wireless communication.

[0048] The energy storage cells 13 serve to absorb, store, and re-release electrical energy. The energy storage cells 13 are cylindrical in shape and based on lithium-ion technology. Each energy storage cell 13 contains a contact device at one end, which serves to transmit electrical energy. The individual contact devices are connected to the control device 15 of the accumulator 5 via corresponding lines.

[0049] Alternatively, the energy storage cells 13 may also be based on another suitable technology.

[0050] The cylindrical shape of the energy storage cells 13 is also optional, so any other suitable shape or geometry can be selected. In particular, it is also possible for the energy storage cells 13 to be designed as pouch cells. It is also possible for the accumulator 5 to contain both cylindrical energy storage cells 13 and pouch cells. In particular, it is possible for the accumulator 5 to contain only a single cylindrical energy storage cell 13 and a single pouch cell.

[0051] The control device 15 regulates and controls various functions of the accumulator 5. These functions include, among others, controlling the absorption and release of electrical energy into and from the energy storage cells 13. Furthermore, the control device 15 controls the amount of electrical energy to be absorbed or released by the energy storage cells 13.

[0052] The electric motor 9 is designed in the form of a brushless electric motor and essentially contains a stator 16 and a rotor 17, see Figure 2. The rotor 17 is positioned rotatably about a central axis R inside the stator 16.

[0053] Figures 3 to 7 show a stator 16 according to an exemplary embodiment. The stator 16 essentially contains a stator laminated core 22 with six radially inwardly directed pole teeth 19. The stator laminated core 22 essentially consists of a number of profiled sheets stacked one above the other.

[0054] Two pole teeth 19 are positioned opposite each other. According to an alternative embodiment, more or fewer than six pole teeth 19 can be provided. The pole teeth 19 serve to respectively accommodate a coil wire 21 to create a coil 24. The coils 24 are connected to the power supply 5 via the control device 12 in order to apply an electrical voltage to the coils 24. In other words, the coils 24 are energized. With the help of the coils 24, an alternating magnetic field is generated, which causes the rotor 17 to rotate about the central axis R.

[0055] The stator core 22 has a winding support 23 at a first end 22a, which is positioned in the direction of arrow A above or at the first end 22a of the stator core 22. The winding support 23 essentially serves to support the coil wire 21 around the pole teeth 19. As indicated in the figures, the free ends 21a of the coil wire 21 emerge from the winding support 23 at the first end 22a of the stator core 22.

[0056] Furthermore, a first, second, and third contact rail 25 are positioned in the direction of arrow A. The first, second, and third contact rails 25 are essentially identical in design. Figure 4 shows a contact rail 25 according to a first exemplary embodiment. The contact rail 25 essentially has an elongated, curved base body 26. The arc or radius of the curved base body 26 is selected such that the base body 26 can be placed against the circular arc of the stator laminated core 22. As can be seen in particular in Figure 3, the base body 26 of the contact rail 25 lies in a correspondingly curved recess 27 in the winding support 23 and follows the shape of the stator laminated core 22.

[0057] A first clamping element 28a is provided at a first end 26a of the base body 26. The first clamping element 28a serves to receive and hold a coil wire 21 of a coil 24. A first connection element 30 is provided at a second end 26b of the base body 26. The first connection element 30 is connected by a first end 30a to the second end 26b of the base body 26. A first end 32a of a connecting element 32 is fastened to a second end 30b of the first connection element 30. A first end 31a of a second connection element 31 is fastened to a second end 32b of the connecting element 32. According to a first exemplary embodiment, the connecting element 32 is designed as a web with a right angle (= 90°). Due to the design of the connecting element 32 with a right angle, the first connection element 30 is positioned in a first plane E1 and the second connection element 31 is positioned in a second plane E2.The first plane E1 and the second plane E1 are configured as two intersecting planes and are arranged substantially orthogonally to one another. As a result, the first and second connecting elements 30, 31 are arranged orthogonally to one another.

[0058] Alternatively, the first and second planes E1, E2 are arranged at a flat or acute angle to each other, ie at an angle to each other that is greater or less than 90°.

[0059] In addition, a second clamping element 28b is provided on the first connection element 30. As can be seen in Figure 3, the second clamping element 28b projects downward from the second connection element 28b in the opposite direction to the arrow A. Like the first clamping element 28a, the second clamping element 28b also serves to receive and hold a coil wire of a coil 24. The first clamping element 28a serves to receive and hold a first coil wire 21 of a first coil 24, and the second clamping element 28b in turn serves to receive and hold a second coil wire 21 of a second coil 24. The first and second coils 24 are arranged opposite one another, see Figure 7. As can be seen particularly clearly in Figure 4, the first and second clamping elements 28a, 28b are in the form of a bent sheet metal element, into which the end 21a of a winding wire 21 is inserted and clamped by bending the sheet metal element.

[0060] According to an alternative embodiment, the first and second clamping elements 28a, 28b can also be designed as straight sheets for welding an end 21a of a winding wire 21.

[0061] According to a first exemplary embodiment, the first and second connecting elements 30, 31 are each configured in the form of a through-hole with an internal thread 33. The internal thread 33 serves to releasably connect the contact rail 25 to a power cable 34a, 34b, 34c, see Figures 5 to 7. As shown in Figures 5 to 7, a screw 35 is screwed into each through-hole to releasably attach a power cable 34a, 34b, 34c to a contact rail 25.

[0062] The power cable 34a, 34b, 34c serves to supply the contact rail 25 and finally the coil 24 with electrical energy from the power supply 5.

[0063] According to an alternative embodiment, at least one connecting element 30, 31 can be designed such that a power cable 34a, 34b, 34c can be welded, soldered, or simply plugged into the contact rail 25. For a corresponding plug-in connection, the connecting element 30, 31 can be designed as a socket, and the end of a power cable 34a, 34b, 34c can be designed as a plug corresponding to the socket.

[0064] Figure 5 shows the stator 16, in which a first power cable 34a is connected to a second connection element 31 of a first contact rail 25, a second power cable 34b is connected to a second connection element 31 of a second contact rail 25, and a third power cable 34c is connected to a second connection element 33 of a third contact rail 25. The three power cables 34a, 34b, 34c are thus connected to the stator 16 in the radial direction, so that the power cables 34a, 34b, 34c run in the axial direction (= in direction A). The first connection elements 30 of the respective contact rails 25 are not occupied.

[0065] Figure 6 shows the stator 16, in which a first power cable 34a is connected to a second connection element 31 of a first contact rail 25, a second power cable 34b is connected to a second connection element 31 of a second contact rail 25, and a third power cable 34c is connected to a second connection element 31 of a third contact rail 25. The three power cables 34a, 34b, 34c are thus connected to the stator 16 in the radial direction, although the respective power cables 34a, 34b, 34c run in a tangential direction to the stator laminated core 22 for a first section. After the first section, the power cables 34a, 34b, 34c then run in the radial direction. The first connection elements 30 of the respective contact rails 25 are again unoccupied.

[0066] Figure 7 shows the stator 16, in which a first power cable 34a is connected to a first connection element 30 of a first contact rail 25, a second power cable 34b is connected to a first connection element 30 of a second contact rail 25, and a third power cable 34c is connected to a first connection element 30 of a third contact rail 25. The three power cables 34a, 34b, 34c are thus connected to the stator 16 in the axial direction, so that the respective power cables 34a, 34b, 34c run in a radial direction. The second connection elements 31 of the respective contact rails 25 are not occupied.

[0067] Reference symbol

[0068] 1 machine tool

[0069] 2 housings

[0070] 2a front end of the housing

[0071] 2b rear end of the housing

[0072] 2c upper end of the housing

[0073] 2d lower end of the housing

[0074] 3 Handle

[0075] 3a first end of the handle

[0076] 3b second end of the handle

[0077] 4 tool holder

[0078] 5 Energy supply

[0079] 6 Interface

[0080] 8 activation switches

[0081] 9 Electric motor

[0082] 10 Gear device

[0083] 11 Drive shaft

[0084] 12 Control device

[0085] 13 Energy storage cell

[0086] 14 Battery interface

[0087] 15 Control device

[0088] 16 Stator

[0089] 17 Rotor

[0090] 19 Pole tooth

[0091] 20 battery housings

[0092] 21 coil wire

[0093] 21a End of a coil wire

[0094] 22 Stator laminated core

[0095] 22a first end of the stator core

[0096] 23 Winding support 24 Coil

[0097] 25 contact rail

[0098] 26 Base body of the contact rail

[0099] 26a first end of the base body

[0100] 26b second end of the base body

[0101] 27 Recess on the changing support

[0102] 28a first clamping element

[0103] 28b second clamping element

[0104] 30 first connecting element

[0105] 30a first end of the first connecting element

[0106] 30b second end of the first connecting element

[0107] 31 second connecting element

[0108] 31a first end of the second connecting element

[0109] 31 b second end of the second connecting element

[0110] 32 connecting element

[0111] 32a first end of a connecting element

[0112] 32b second end of a connecting element

[0113] 33 internal thread

[0114] 34a first power cable

[0115] 34b second power cable

[0116] 34c third power cable

[0117] 35 screw

[0118] R central axis

[0119] E1 first level

[0120] E2 second level

Claims

Patent claims 1. Stator (16) for an electric motor (9), in particular as a drive for a machine tool (1), containing a stator laminated core (22) with at least one first and second pole tooth (19) for respectively receiving and holding at least one coil wire (21) and at least one first and second contact rail (25) for electrically contacting a respective coil wire (21), characterized in that each contact rail (25) contains at least one first and second connection element (30, 31), wherein the first connection element (30) is positioned in a first plane (E1) and the second connection element (31) is positioned in a second plane (E2).

2. Stator (16) according to claim 1, characterized in that the first and second planes (E1, E2) are designed as two intersecting planes.

3. Stator (16) according to claim 1 or 2, characterized in that the first and second planes (E1, E2) are arranged substantially orthogonally to one another.

4. Stator (16) according to at least one of claims 1 to 3, characterized in that the first and / or second connecting element (30, 31) is designed for a material-locking, form-locking and / or force-locking connection to a power cable (34a, 34b, 34c).

5. Stator (16) according to at least one of claims 1 to 4, characterized in that the first and / or second connecting element (30, 31) is designed for welding, soldering, screwing and / or plugging onto a power cable (34a, 34b, 34c).

6. Stator (16) according to at least one of claims 1 to 5, characterized in that the first and / or second connecting element (30, 31) is designed as a bushing.

7. Electric motor with a stator (16) according to at least one of claims 1 to 6.

8. Machine tool with a stator (16) according to at least one of claims 1 to 6.

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