Contactor comprising electric motor and commutator-brush system

Abstract

The invention relates to a contactor comprising an electric motor (2) comprising a stator (200) and a rotor (201) and a commutator-brush system (3), the commutator-brush system comprising: a commutator (300) assembled on the rotor, the commutator comprising at least one electrically conductive portion (302) and at least one non-electrically conductive portion (303); and a pair of brushes formed of two brushes (304), wherein the brushes each have a contact surface configured to frictionally contact the commutator. The side surface of the commutator (300) comprises a conductive portion (302) and a non-conductive portion (303) of the commutator, wherein the commutator is free to rotate about an axis of rotation (X). The commutator-brush system (3) is configured to move between an electrically conductive position, in which the commutator electrically connects the pair of brushes, and an interrupted position, in which the commutator electrically isolates the pair of brushes (304), the commutator-brush system transitions from the electrically conductive position to the interrupted position by rotation of the commutator (300) under the action of the motor, and transitioning from the interruption position to the conductive position.

Description

[0001] This invention relates to the field of contactors, and more particularly to contactors designed for operation in harsh vibration environments.

[0002] Electrical contactors are typically formed by levers or strips, allowing electrical contact or isolation through the limited rotational movement of the levers, depending on their position. Other types of electrical contact use the translational movement of two conductive parts. Other types of contact use a selector on a contact track against the rotation of a strip, such as the rotary contactor described in French patent application FR 2407562.

[0003] The drawback of these systems is the inherent sensitivity of contact elements (such as levers and strips) to shocks, vibrations, and accelerations, which can cause damage or translational or rotational motion that creates electrical contact.

[0004] One solution to this problem involves increasing the holding force of the contacts. However, this would require more power to switch the contacts, especially when the contactor must switch a large number of contacts.

[0005] The purpose of this invention is to provide a contactor that can operate in harsh vibration environments without requiring significant power to switch contacts.

[0006] Therefore, the present invention provides a contactor including a motor and a commutator-brush system. The motor is configured to be attached to a frame and includes a coaxial stator and a rotor. The rotor is configured to rotate freely about a rotation axis. The commutator-brush system includes: A commutator, assembled on the rotor of the electric motor, the commutator having a cylindrical shape and including at least one conductive portion and at least one non-conductive portion; and A pair of brushes formed by two brushes, wherein the brushes are configured to be attached to the frame, and each brush has a contact surface configured to frictionally contact the commutator.

[0007] According to the invention, the side surface of the commutator includes at least one conductive portion and at least one non-conductive portion of the commutator. The commutator is freely rotatable about the rotation axis. The commutator-brush system is configured to move between a conductive position and an interrupted position, in which the commutator electrically connects the pair of brushes, and in the interrupted position, the commutator electrically isolates the pair of brushes. When the commutator-brush system is in the conductive position, at least one conductive portion is in contact with the brushes, and no non-conductive portion extends between the two brushes; and when the commutator-brush system is in the interrupted position, the non-conductive portion is in contact with at least one of the brushes in the pair of brushes, or the non-conductive portion extends between the two brushes in the pair of brushes. The commutator rotates around the rotating shaft under the action of the motor, and the commutator-brush system changes from the conductive position to the interrupted position and from the interrupted position to the conductive position.

[0008] The resulting contactor has reduced sensitivity to any vibrations from its rotating configuration. In fact, the symmetrical structure of the motor, particularly the symmetrical structure of its rotor, and the mounting of the commutator on the rotor, allows for a balanced contactor. This balance prevents any shock or vibration from moving the commutator (especially its contacts formed by multiple pairs of brushes).

[0009] Furthermore, due to the low frictional torque of the brushes on the commutator, low electrical power is required to transition from the conducting position to the interrupted position and vice versa. This allows for the simultaneous control of several contacts with reduced power used to power the contactor.

[0010] The preferred features according to the invention, which are particularly useful for contactors, are described below.

[0011] When the commutator-brush system is in the conductive position, the same conductive portion contacts two of the two brushes in the pair of brushes, and when the commutator-brush system is in the interrupted position, at least one non-conductive portion contacts at least one of the two brushes in the pair of brushes.

[0012] The commutator includes at least two conductive portions, wherein a gap separates two adjacent conductive portions and forms the at least one non-conductive portion, wherein when the commutator-brush system is in the interrupted position, the adjacent conductive portions each contact one of the pair of brushes.

[0013] The conductive part is made of copper, and the non-conductive part is made of plastic material.

[0014] The rotor extends around the stator, wherein the commutator is mounted on a side surface of the rotor.

[0015] The stator extends around the rotor, wherein the motor includes a shaft, the rotor is mounted on the shaft, and the commutator is mounted on the shaft.

[0016] The electric motor is a finite-stroke magnet motor.

[0017] The contactor includes a stop member configured to be assembled on the frame, wherein the stop member includes an assembly element configured to engage with a mating assembly element formed in the rotor.

[0018] The contactor includes multiple pairs of brushes, each pair consisting of two brushes.

[0019] Other features and advantages of the invention will become clearer from the following description, with reference to the accompanying drawings, which are provided by way of non-limiting example: Figure 1 A perspective view and a top view of a contactor according to a first embodiment of the present invention are shown, wherein the contactor is in a connected configuration; Figure 2 This is a detailed view of the contactor's brush assembly; Figure 3 The perspective and top views of the contactor in the disconnected configuration are shown; Figure 4 The circuit of the contactor is schematically shown; Figure 5 This is a perspective view of a contactor according to a second embodiment of the present invention; and Figure 6 A contactor according to a third embodiment of the present invention is shown.

[0020] Figures 1 to 3 A contactor 1 according to an embodiment of the present invention is shown. Figure 4 The circuit of contactor 1 is schematically shown in the figure.

[0021] The contactor includes a motor 2 and a commutator-brush system 3.

[0022] The contactor also includes a frame (not shown in the figure).

[0023] The electric motor 2 forms the control part of the contactor.

[0024] The electric motor 2 includes a stator 200 and a rotor 201. The stator 200 forms an attachment portion of the electric motor 2, and the rotor 201 forms a rotating portion. The rotor 201 is configured to rotate about a rotation axis X. The stator 200 and the rotor 201 are coaxial.

[0025] exist Figures 1 to 3 In the illustrated embodiment, the rotor 201 extends around the stator 200. Figure 6 In the variant shown, the stator 200 can extend around the rotor 201.

[0026] The electric motor also includes an interface component 203. The interface component 203 is configured to be attached to the frame of the contactor 1. In this case, the interface component 203 is attached to one end 204 of the stator 200.

[0027] Motor 2 is, for example, a finite-stroke permanent magnet type. A finite-stroke motor consists of a single-winding coil. Supplying DC current to the winding in the positive direction allows the motor to rotate in a given direction of rotation. Supplying DC current to the winding in the negative direction allows the motor to rotate in the opposite direction.

[0028] Using a magnet motor is also advantageous because the motor is inherently balanced. The motor is especially balanced when the magnets are offset from each other in the same direction.

[0029] In one variant, the motor includes two coils in opposite phases. Supplying positive direct current to the first coil allows rotation, for example, in a first direction, and supplying positive direct current to the second winding allows the motor to rotate in a second direction opposite to the first direction.

[0030] In one embodiment, one or both coils of the motor are connected in series with a reverse polarity protection diode. This prevents any connection or command errors.

[0031] The brush-commutator system 3 forms the electrical contact portion of the contactor.

[0032] The commutator-brush system 3 includes a commutator 300 and a brush assembly 301.

[0033] The commutator 300 has a cylindrical shape. In particular, in this case, the commutator 300 has a ring shape.

[0034] The commutator 300 includes at least one conductive portion 302 and at least one non-conductive portion 303.

[0035] exist Figures 1 to 3 In the example shown, the commutator includes multiple conductive portions 302 and non-conductive portions 303. The commutator 300 includes alternating conductive portions 302 and non-conductive portions 303. In other words, any conductive portion 302 is circumferentially adjacent to a non-conductive portion 303. The conductive portions 302... Figures 1 to 3 and Figure 6 It is marked with a shading line.

[0036] In the example shown, and as in Figure 2 As clearly shown, the conductive portion 302 is inserted into the isolation support. The portion of the isolation support extending between the conductive portions 302 forms a non-conductive portion 303. Alternatively, the conductive portions 302 and the non-conductive portions 303 can be completely separated.

[0037] The conductive portion 302 and the non-conductive portion 303 form the periphery of the commutator 300. In other words, the surfaces of the conductive portion 302 and the non-conductive portion 303 form the side surfaces of the commutator 300.

[0038] In this configuration, the conductive portion 302 and the non-conductive portion 303 have the same shape. Alternatively, the conductive portion 302 and the non-conductive portion 303 can be strips. Alternatively, the conductive portion 302 and the non-conductive portion 303 can have rectangular shapes. In this configuration, the conductive portion 302 is narrower than the non-conductive portion 303.

[0039] Using the same conductive and non-conductive parts (e.g., strips) allows the commutator to be balanced.

[0040] In other embodiments, the conductive portion 302 and the non-conductive portion 303 may have different shapes and / or different sizes. For example, the conductive portion 302 and the non-conductive portion 303 may be rectangular strips with the same width.

[0041] The conductive part 302 can be made of any conductive material, such as a metal like copper.

[0042] The non-conductive portion 303 can be made of any insulating material, such as plastic.

[0043] The non-conductive portion 303 can also be formed by a gap separating the conductive portions. Air in the gap provides electrical isolation between the conductive portions 302. In one embodiment of the invention, the gap is formed by dividing the conductive strip into two, such as... Figure 5 As shown, and described below with reference to the figure. In another embodiment not shown, a gap may be used instead. Figures 1 to 3 In the embodiment shown, the non-conductive portion 303 extends.

[0044] The commutator 300 is mounted on the rotor 201 of the electric motor 2. The commutator 300 rotates freely about the rotation axis X. The commutator 300 is driven by the electric motor 2. Rotation of the rotor 201 in one direction causes the commutator 300 to rotate in the same direction.

[0045] In the example shown, rotor 201 forms the external armature of motor 2, and stator 200 forms the internal armature of motor 2. Commutator 300 is mounted on the side surface of rotor 201. In other words, commutator 300 is mounted around motor 2, thereby limiting the height of contactor 1, i.e., the dimension of contactor 1 in the direction of rotation axis X. The resulting contactor is compact.

[0046] In an embodiment where the stator 200 of the electric motor extends around the rotor 201, the commutator 300 can be mounted on the rotor 201 in another manner. The commutator 300 can be mounted on the output shaft 205 of the electric motor 2, such as... Figure 6 As shown.

[0047] The brush assembly 301 includes at least one pair of brushes 304 (in Figure 2(Clearly shown in the image).

[0048] Each pair of brushes 304 is connected to the input and output of contactor 1.

[0049] Each brush 304 includes a contact surface 305. The contact surface 305 of the brush 304 is configured as a friction commutator 300. A pair of brushes 304 forms the contacts of the contactor 1. The contactor 1 may include multiple pairs of brushes 304, thereby allowing switching of several lines using the same commutator 300. Figure 1 and Figure 2 The diagram shows eight pairs of brushes (i.e., sixteen brushes), but of course, brush assemblies can include different numbers of brushes. The number of brush pairs depends on the desired number of contacts.

[0050] Brushes 304 are made of carbon, for example.

[0051] The brush assembly 301 also includes at least one brush holder 306 and a support 307. In this case, the brush assembly 301 includes eight brush holders 306.

[0052] Each brush holder 306 accommodates a pair of brushes 304. The brush holder 306 includes two cages 308. Each cage 308 is configured to accommodate one of the brushes 304.

[0053] The brush holder 306 is mounted on the support 307. The support 307 has an annular shape. The support 307 extends around the commutator 300. The support 307 is orthogonal to the rotation axis X.

[0054] The support 307 includes, for example, a conductive plate made of steel.

[0055] In the example shown, the retainer 308 of the brush holder is arranged on either side of the support 307. Each pair of brushes 304 is positioned axially above the other relative to the commutator 300. Each pair of brushes 304 is arranged around the commutator 300.

[0056] Alternatively, the retainers 308 may be arranged circumferentially adjacent to each other. Each pair of brushes 304 is positioned adjacent to each other around the commutator 300. For example, the retainers 308 may be arranged on the same side of the support 307.

[0057] Each retainer 308 houses at least one spring (not shown). The spring is configured to push the brush 304 against the commutator 300. The spring permanently applies a force to the brush, which tends to push the brush against the commutator. This ensures good contact between the brush and the commutator.

[0058] Due to the spring, brush 304 is said to be preloaded. Even under impact, vibration, or acceleration, brush 304 remains in contact. Since commutator-brush systems are used in applications that operate by rotating at relatively high speeds (on the order of 50 m / s) over extended periods, the frictional torque of the brushes on the commutator will remain relatively low.

[0059] The brush assembly 301 is configured to be attached to the frame (not shown) of the contactor 1.

[0060] The contactor 1 also includes at least one stop element 4. The stop element 4 is configured to limit the rotation of the motor 2.

[0061] On one hand, the stop component 4 is assembled to the frame (not shown), and on the other hand, the stop component 4 is assembled to the rotor 201.

[0062] The stop component 4 includes an assembly element 401 configured to engage with a matching assembly element 202 formed in the rotor 201.

[0063] In the example shown, assembly element 401 is a finger. Matching assembly element 202 is a notch. The notch 202 is configured to receive the finger 401. The finger 401 is configured to move within the notch 202.

[0064] According to one variation, the assembly element can be a notch, and the mating assembly element can be a finger.

[0065] In this configuration, the stop member 4 includes a plate 402 that extends orthogonally from the assembly element 401. The plate 402 includes a hole 400. The hole 400 has a rectangular shape. The plate 402 allows the stop member 4 to be attached to the frame. The stop member is attached to the frame, for example, by means of a screw inserted into the hole 400. The rectangular shape of the hole 400 allows adjustment of the position of the stop member 4 relative to the frame. In this configuration, the contactor 1 includes the stop member 4. Alternatively, the contactor 1 may clearly include multiple stop members 4.

[0066] The rotor 201 may include a plurality of notches 202. One or more of the notches 202 may be configured to engage with one or more stop members 4. In one embodiment, the number of stop members 4 and the number of notches 202 may be the same. Each stop member 4 is then configured to engage with one of the notches 202. In another embodiment, the number of notches 202 may be greater than the number of stop members 4. One or more stop members are each configured to engage with one of the notches 202. The additional notches 202 (i.e., in addition to the number of stop members 4) allow any imbalance on the rotor to be minimized. If the imbalance is sufficiently reduced, the effects of shocks, vibrations, or accelerations on the rotor and commutator will produce negligible torques, most of which can be compensated by the torque used to hold the motor. Even in the event of shocks, vibrations, or accelerations, the commutator will not move.

[0067] The notch 202 can be made symmetrical with respect to the rotation axis X. The rotor 201 may include, for example, three notches 202, each positioned at 120° relative to each other.

[0068] exist Figure 1 and Figure 2 In the example shown, rotor 201 includes three notches 202, and contactor 1 includes a stop member 4.

[0069] When the motor has a finite stroke permanent magnet type, one or more stop components 4 are placed in a manner that limits the rotation of the finite stroke motor within the operating range of the contactor.

[0070] Figure 5 Another embodiment of the contactor 1 according to the present invention is shown. In this example, the commutator includes a continuous strip 302 and a separate strip 309. The continuous strip forms a conductive portion 302. The separate strip 309 includes two components 310. The two components 310 are made, for example, of the same material as the conductive portion 302. In other words, the components 310 are separate conductive portions.

[0071] Each separation strip 309 also includes a gap 311 between two components 310. The gap 311 forms an electrical isolation element. In other words, the gap 311 forms a non-conductive portion 303.

[0072] In another embodiment, the commutator may include a plurality of conductive portions separated from each other by gaps. Adjacent conductive portions may have different dimensions. Adjacent conductive portions may be, for example, strips of different widths. Brushes may be arranged circumferentially around the commutator.

[0073] The operation of the contactor is described below. This description is provided for a single contact and therefore for a pair of 304 brushes, but of course, it applies to a larger number of contacts.

[0074] The commutator-brush system 3 can move between a conductive position and an interrupted position. In the conductive position, the commutator 300 electrically connects a pair of brushes 304. Therefore, the contacts are closed. In the interrupted position, the commutator 300 electrically isolates the pair of brushes 304. Therefore, the contacts are open.

[0075] The commutator-brush system 3, under the action of the motor 2, changes from a conductive position to an interrupted position by rotating the commutator 300 around the rotation axis X, and vice versa. The commutator-brush system 3 can change from a conductive position to an interrupted position by rotating the commutator 300 in a first rotation direction, and from an interrupted position to a conductive position by rotating the commutator 300 in a second rotation direction opposite to the first rotation direction.

[0076] When the commutator 300 includes multiple pairs of brushes 304, the commutator-brush system 3 has several conductive positions and interrupted positions. More specifically, the commutator-brush system 3 has at least one conductive position and at least one interrupted position associated with each pair of brushes 304.

[0077] At the conductive location, a pair of brushes 304 rub against the conductive portion 302, such as... Figure 1 and Figure 2 As shown.

[0078] The interrupt location depends on the configuration of commutator 300. Figures 1 to 3 In the example shown, the commutator is in the interrupted position when the non-conductive portion 303 faces the pair of brushes 304. In other words, the commutator-brush system 3 is in the interrupted position when the non-conductive portion 303 is in contact with the pair of brushes 304. Figure 3 The diagram shows a commutator in an interrupted position.

[0079] In one embodiment, the commutator-brush system is in an interrupted position when each of the brushes in a pair of brushes contacts one of the conductive portions 302, wherein the conductive portions 302 are isolated from each other. The conductive portions 302 may be isolated from each other by the presence of an insulating material or a gap.

[0080] According to a variation, the commutator-brush system is in an interrupted position when the conductive part is in contact with one of the brushes in a pair and the non-conductive part is in contact with the other brush in the pair.

[0081] exist Figure 5 In the illustrated embodiment, the commutator-brush system is in a conductive position when two of the two brushes 304 in a pair are in contact with the complete strip 302. The commutator-brush system is in an interrupted position when each brush 304 is in contact with a portion 310 of the separated strip 309.

[0082] In embodiments where adjacent conductive portions have different widths separated from each other by gaps, the commutator-brush system is in a conductive position when both brushes in a pair are in contact with the same conductive portion. The commutator-brush system is in an interrupted position when each brush in a pair is in contact with a different conductive portion.

[0083] Contactor 1 is configured to operate in a connected and disconnected configuration. In the connected configuration, the commutator-brush system 3 is in a conductive position. Therefore, the contacts formed by the pair of brushes 304 and the commutator 300 are closed. In the disconnected configuration, the commutator-brush system 3 is in an open position. Therefore, the contacts formed by the pair of brushes 304 and the commutator 300 are open.

[0084] Under the action of the motor, the contactor 1 changes from the connected configuration to the disconnected configuration by the rotation of the commutator 300 around the rotating axis X, and vice versa.

[0085] The electric motor 2 forms the control section of the contactor 1. One or more windings form the control circuit of the contactor 1. The power supply of the electric motor allows the commutator to rotate in order to create open or closed contacts between the brushes 304.

[0086] When the contactor includes at least one stop member 4, the stop member 4 can be positioned to limit the rotation of the motor 2 and thus limit the rotation of the commutator-brush system 3 between the conductive position and the interrupted position.

[0087] When the motor 2 is a magnet motor, it can be configured to obtain torque for holding the magnet in position in one or more stop members 4. This allows the conductive or interrupted position to be maintained even when the motor 2 is not powered.

[0088] The contactor according to the invention is particularly suitable for use in environments with severe vibration, especially due to its balance. The contactor also requires low power to open or close one or more contacts.

Claims

1. A contactor comprising a motor (2) and a commutator-brush system (3), said motor (2) being configured to be attached to a frame and comprising a coaxial stator (200) and a rotor (201), said rotor (201) being configured to rotate freely about a rotation axis (X), said commutator-brush system (3) comprising: A commutator (300) assembled on the rotor (201) of the motor (2), the commutator (300) having a cylindrical shape and including at least one conductive portion (302) and at least one non-conductive portion (303); and A pair of brushes formed by two brushes (304), wherein the brushes (304) are configured to be attached to the frame, and each brush (304) has a contact surface (305) configured to frictionally contact the commutator (300). The contactor (1) is characterized in that the side surface of the commutator (300) includes at least one conductive portion (302) and at least one non-conductive portion (303) of the commutator (300), and the commutator (300) rotates freely about the rotation axis (X). The commutator-brush system (3) is configured to move between a conductive position and an interrupted position, wherein in the conductive position, the commutator (300) electrically connects the pair of brushes (304), and in the interrupted position, the commutator (300) electrically isolates the pair of brushes (304), wherein when the commutator-brush system (3) is in the conductive position, at least one conductive portion (302) contacts the brushes (304), and no non-conductive portion (303) extends between the two brushes (304), wherein when the commutator-brush system (3) is in the interrupted position, the non-conductive portion (303) contacts at least one of the brushes (304) in the pair of brushes, or the non-conductive portion (303) extends between the two brushes (304) in the pair of brushes. The commutator (300) rotates around the rotating axis (X) under the action of the motor (2), and the commutator-brush system (3) changes from the conductive position to the interrupted position and from the interrupted position to the conductive position.

2. The contactor according to claim 1, wherein, When the commutator-brush system (3) is in the conductive position, the same conductive portion (302) contacts the two brushes (304) of the pair of brushes, and when the commutator-brush system (3) is in the interrupted position, at least one non-conductive portion (303) contacts at least one brush (304) of the pair of brushes.

3. The contactor according to claim 1, wherein, The commutator (300) includes at least two conductive portions (302, 310), wherein a gap (311) separates two adjacent conductive portions (302, 310), the gap (311) forming the at least one non-conductive portion (303), and when the commutator-brush system (3) is in the interrupted position, the adjacent conductive portions (302, 310) each contact one of the brushes (304) in the pair of brushes.

4. The contactor according to claim 1 or claim 2, wherein, The at least one conductive portion (302) is made of copper, and the at least one non-conductive portion (303) is made of plastic material.

5. The contactor according to any one of claims 1 to 4, wherein, The rotor (201) extends around the stator (200), wherein the commutator (300) is mounted on a side surface of the rotor (201).

6. The contactor according to any one of claims 1 to 4, wherein, The stator (200) extends around the rotor (201), wherein the motor (2) includes a shaft (205), the rotor (201) is mounted on the shaft (205), and the commutator (300) is mounted on the shaft (205).

7. The contactor according to any one of claims 1 to 6, wherein, The motor (2) is a finite stroke magnet motor.

8. The contactor according to any one of claims 1 to 7, comprising a stop member (4) configured to be assembled on the frame, the stop member (4) comprising an assembly element (401) configured to engage with a mating assembly element (202) formed in the rotor (201).

9. The contactor according to any one of claims 1 to 8, comprising a plurality of pairs of brushes, each pair of brushes being formed by two brushes (304).

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