End face commutator direct drive starter

Abstract

The utility model relates to a direct -current motor structure field discloses an end face commutator direct drive starter, including front cover, back cover, permanent magnet stator, casing, drive gear and be located in the armature of stator. Armature contains armature shaft, armature core and end face commutator, and the surface of armature core is equipped with wire slot, and the end face commutator has a plurality of commutating sheet with axial bending terminal hook. Armature wire is single continuous wire, and reciprocatingly is wound in each wire slot and forms multi -turn coil, and its first end, end and a plurality of intermediate end are fixed on the terminal hook of different commutating sheet respectively. The structure combines end face commutator and single wire continuous winding, significantly shortens armature and whole machine axial dimension, reduces copper material consumption, simplifies winding, welding technology, reduces the dependence on special equipment, effectively inhibits electric spark, reduces carbon brush wear and tear simultaneously, improves structural stability, prolongs the service life, and is applicable to small -power direct -current direct drive starting system.

Description

Technical Field

[0001] This utility model relates to the field of DC motor structure and discloses a direct-drive starter with an end-face commutator. Background Technology

[0002] As a key component of an internal combustion engine, the starter motor's core function is to convert electrical energy from the battery into mechanical energy to drive the engine flywheel and complete ignition. The armature, as the energy conversion core of the starter motor, directly impacts the overall reliability and market competitiveness of the machine due to its performance and manufacturing cost. Currently, most mainstream low-power starters on the market employ a traditional radial commutator armature structure, coupled with complex components such as electromagnetic switches and one-way clutches to achieve engagement and disengagement with the engine flywheel.

[0003] However, during the development of this utility model, it was discovered that existing conventional starter solutions of this type have significant systemic defects. First, the radial commutator armature itself results in a long axial dimension. Combined with the need to incorporate the electromagnetic switch and one-way switch, this leads to a complex and bulky starter structure, making it difficult to meet the compact layout requirements of modern engine compartments. Second, this solution has significant drawbacks in manufacturing: not only does the armature winding and welding rely on specialized equipment, resulting in complex processes and high costs, but the assembly of the entire machine involves multiple precision components, further increasing manufacturing costs and failure rates, making it unsuitable for large-scale and low-cost production. Furthermore, in terms of performance, the radial commutator and carbon brushes are prone to generating large electrical sparks, which not only accelerates carbon brush wear but also affects the lifespan of the electromagnetic switch contacts, posing a challenge to the overall durability of the starter.

[0004] While some starter motor designs exist on the market that aim for localized optimization, such as simplifying armature connections or using different types of clutches, they generally struggle to achieve a good balance between overall cost, structural complexity, manufacturing processes, and long-term operational reliability. Most solutions, while simplifying one aspect, often introduce new problems in another, such as decreased connection reliability or insufficient transmission efficiency, making it difficult to meet the demanding operating requirements of starter motors under high torque and high-impact conditions.

[0005] In summary, existing technologies lack a starter system solution that simultaneously achieves a compact overall structure, low material and manufacturing costs, simple production processes, and a longer service life. Therefore, there is an urgent need for an innovative overall framework and core component solution to fundamentally overcome the systemic shortcomings of existing technologies and meet the market's increasingly demanding requirements for low-power DC starters in terms of cost, performance, and manufacturing processes. Utility Model Content

[0006] This utility model discloses a direct-drive starter with an end-face commutator, which can achieve a compact design of the overall starter structure and significantly reduce material and production costs. By adopting an end-face commutator armature and a direct-drive transmission structure, the axial dimension of the whole machine is effectively shortened, and the assembly and welding process is simplified. At the same time, it systematically solves the problems of complex structure, high copper consumption, reliance on specialized equipment for production process and large commutation electric sparks in traditional starters due to the use of radial commutators, electromagnetic switches and one-way clutches.

[0007] To achieve the above objectives, this utility model provides a direct-drive starter with an end-face commutator, including a front cover, a rear cover, a permanent magnet stator, a housing, and a drive gear. The permanent magnet stator is disposed inside the housing. The feature is that it also includes an armature disposed inside the permanent magnet stator. The armature has an armature shaft on which the armature core and the end face commutator are sequentially mounted. The armature core has several grooves arranged circumferentially on its circumferential surface; The end face commutator includes a base and a number of commutator segments fixed on the base and arranged circumferentially. Each commutator segment has a terminal hook formed by bending axially toward the armature shaft at its end. The armature also has a continuously wound armature wire that is repeatedly wound in multiple slots to form a multi-turn coil. The armature wire includes a start end, an end end, and multiple intermediate ends, which are respectively wound and fixed on different hooks.

[0008] Preferably, a brush holder assembly is fixedly mounted on the rear cover by connecting screws; The brush holder assembly includes a brush holder base plate, a positive carbon brush, a negative carbon brush, and a compression spring that provides pressure to the positive and negative carbon brushes, all mounted on the brush holder base plate. The brush holder base plate serves as the base of the brush holder assembly and is directly fixed to the rear cover using connecting screws.

[0009] Preferably, a drive gear is fixedly installed at the front end of the armature shaft; a retaining ring groove is also provided at the front end of the armature shaft, and a shaft retaining ring is fitted into the retaining ring groove.

[0010] Preferably, insulating end plates are tightly fastened to both ends of the armature core along its axial direction.

[0011] Preferably, the starting end, ending end, and intermediate connecting parts of the armature wire are fixed to the hook by soldering.

[0012] Preferably, the rear cover is also provided with a wiring stud, which passes through a pre-set stud hole on the rear cover and is fixed by a nut at the protruding part; an insulating block is sleeved between the wiring stud and the stud hole of the rear cover.

[0013] Preferably, the front cover is equipped with a needle roller bearing and a skeleton oil seal.

[0014] Preferably, a limiting gasket is also provided between the front end of the armature shaft and the front cover.

[0015] Preferably, each slot of the armature core has slot insulating paper attached to its inner wall, and slot wedges are also embedded in the slot.

[0016] Preferably, the slot wedge is made of an insulating rigid plate.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model include at least the following: This utility model achieves a significant reduction in the axial dimension of the starter and a substantial reduction in the number of parts by adopting a whole-machine design scheme that combines an end-face commutator armature with a permanent magnet direct drive structure. It solves the systemic problems of complex overall structure, large size, and high material cost caused by the use of radial commutators, electromagnetic switches, and one-way clutches in traditional starters. Meanwhile, by adopting an electrical connection method that involves winding and soldering the armature coil and commutator segment hooks, a direct-drive transmission structure between the armature shaft and the drive gear, and a modular integrated brush holder assembly design, the winding, welding, and overall assembly processes are greatly simplified. This reduces reliance on specialized equipment and complex tooling, effectively suppresses commutation sparks, and improves transmission reliability. This solution not only significantly improves production efficiency and cost advantages but also, thanks to its compact structure, fewer parts, and reliable operation, greatly extends the overall service life of the starter motor. It provides a simple, low-cost, process-friendly system solution suitable for mass production for low-power DC starters.

[0018] Other beneficial effects will be described in conjunction with the embodiments. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a structural diagram of the starter motor of this utility model; Figure 2 This is a front view of the rear cover assembly of this utility model; Figure 3 This is a left view of the rear cover assembly of this utility model; Figure 4 This is a structural diagram of the armature of this utility model; Figure 5 This is a partial structural diagram of the rear cover assembly of this utility model; Figure 6 This is a left view of the front cover of this utility model; Figure 7 This is a front view of the armature core of this utility model; Figure 8 This is a structural diagram of the wire groove of this utility model; Figure 9 This is a schematic diagram of the armature wire of this utility model; Figure 10 This is a front view of the end-face commutator of this utility model.

[0021] In the diagram: 1-Front cover, 2-Rear cover, 3-Permanent magnet stator, 4-Housing, 5-Drive gear, 6-Armature, 7-Armature shaft, 8-Armature core, 9-End face commutator, 10-Armature wire, 11-Brush holder base plate, 12-Positive carbon brush, 13-Negative carbon brush, 14-Compression spring, 15-Connecting screw, 16-Clip groove, 17-Shaft clip, 18-Connecting stud, 19-Nut, 20-Insulating block, 21-Needle roller bearing, 22-Skeleton oil seal, 23-Limiting washer, 24-Insulating end plate, 801-Wire groove, 802-Slot insulation paper, 803-Slot wedge, 901-Commutator segment, 9011-Connecting hook. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0024] Example 1 Please see Figures 1 to 10 The present invention provides a direct drive starter with an end face commutator, comprising: a front cover 1, a rear cover 2, a permanent magnet stator 3, a housing 4, a drive gear 5, and an armature 6.

[0025] The permanent magnet stator 3 is disposed inside the housing 4, and the armature 6 is disposed inside the permanent magnet stator 3. The armature 6 has an armature shaft 7, on which an armature core 8 and an end-face commutator 9 are sequentially mounted. To achieve a more secure fit and prevent relative rotation, the central through hole of the armature shaft 7 and the section that mates with the central through hole of the armature core 8 and the end-face commutator 9 are both machined with a knurled structure.

[0026] The armature core 8 has several grooves 801 arranged circumferentially on its circumferential surface. To ensure insulation, the inner wall of each groove 801 is lined with groove insulating paper 802, and a groove wedge 803 made of 3240 epoxy glass cloth is embedded in the groove to press the groove insulating paper 802 and the armature wire 10 together. Insulating end plates 24 are also provided at both ends of the armature core 8 to provide end insulation.

[0027] The end-face commutator 9 includes a base and multiple commutator segments 901 fixed thereon in a circumferentially distributed manner. Each commutator segment 901 has an axially bent hook 9011 at its end. The armature 6 also has a continuous copper wire with a diameter of 1 mm as the armature wire 10. The armature wire 10 is wound repeatedly in the multiple slots 801 of the armature core 8 according to the rule of "slot span 1-5, commutator segment 901 spacing 1-2", and is wound in two rounds in sequence, finally forming a 16-turn coil in each slot 801. During the winding process, the starting end, ending end, and multiple intermediate connecting parts of the armature wire 10 are guided to one side of the end-face commutator 9 and respectively wound and fixed to the hooks 9011 of different commutator segments 901. To ensure the firmness and reliability of the electrical connection, the winding of the armature wire 10 and the hooks 9011 is fixed by soldering.

[0028] The rear cover 2 is equipped with a brush holder assembly, which includes a brush holder base plate 11, a positive carbon brush 12 and a negative carbon brush 13 mounted thereon, and a compression spring 14 that provides pressure to the carbon brushes. The brush holder base plate 11 is directly fixed to the rear cover 2 by connecting screws 15, so that the positive carbon brush 12, the negative carbon brush 13, the brush holder base plate 11 and the rear cover 2 are integrated into a whole. The rear cover 2 is also provided with a terminal stud 18 for connecting an external power source. The terminal stud 18 passes through a pre-set stud hole on the rear cover 2 from the inside out and is fastened by a nut 19 at the protruding part. An insulating block 20 is sleeved between the terminal stud 18 and the stud hole to achieve electrical isolation.

[0029] The front cover 1 is equipped with a needle roller bearing 21 and a skeleton oil seal 22. The front end of the armature shaft 7 passes through the skeleton oil seal 22 and the needle roller bearing 21 in sequence. A limiting washer 23 is also sequentially fitted between the front end of the armature shaft 7 and the interior of the front cover 1. The front end of the armature shaft 7 is provided with a spur spline, and the drive gear 5 directly engages with this spur spline through its inner hole. A retaining ring groove 16 is also provided at the front end of the armature shaft 7, and a shaft retaining ring 17 is fitted into this retaining ring groove 16 and located at the rear end of the drive gear 5 to achieve axial positioning.

[0030] Finally, to improve the overall structural stability and insulation, each slot 801 of the armature core 8 and the coil end of the armature wire 10 are covered with an epoxy varnish layer formed by heating and curing. This epoxy varnish layer can effectively prevent the armature 6 from spinning out when it rotates at high speed and ensure that the coils are mutually insulated.

[0031] The starter assembly process in this embodiment is as follows: First, insert the wiring stud 18 onto the insulating block 20 and through the stud hole in the rear cover 2. Then, use the nut 19 to tighten the wiring stud 18 onto the rear cover 2. Next, place the brush holder base plate 11 into the rear cover 2. Tighten the two negative carbon brushes 13 to the base plate together with the connecting screws 15 onto the rear cover 2. Place the compression spring 14 into the brush holder box on the brush holder base plate 11. Then, install the positive carbon brush 12 and the negative carbon brush 13 into their respective brush holder boxes.

[0032] Next, insert the shaft of armature 6 into the oil-impregnated bearing hole on the rear cover 2. At this time, the end face commutator 9 of armature 6 should press tightly against the positive carbon brush 12 and the negative carbon brush 13. Then, insert the permanent magnet stator 3 into armature 6, so that the marking line on the permanent magnet stator 3 is aligned with the marking line on the rear cover 2.

[0033] Place the limiting shims 23 sequentially at the front end of the armature 6, and install the front cover 1, which has been assembled with the skeleton oil seal 22 and needle roller bearing 21, into the front end of the armature shaft 7, so that the marking line on the front cover 1 is aligned with the marking line at the front end of the permanent magnet stator 3. Then use the nut 19 and the long screw to fasten the front cover 1, the permanent magnet stator 3, and the rear cover 2 into one piece.

[0034] Finally, the drive gear 5 is fitted onto the front end of the armature shaft 7, so that the spur spline of the inner hole of the drive gear 5 engages with the spur spline of the front end of the armature shaft 7, and the shaft retainer 17 is installed into the retainer groove 16 at the front end of the armature shaft 7, thus completing the assembly of the entire starter motor.

[0035] The technical solution provided in this embodiment is as follows: When the starter motor is working, the terminal stud 18 connects to the battery to introduce a 12V power supply. The current is transmitted through the terminal stud 18 to the two positive carbon brushes 12, through the positive carbon brushes 12 to the end face commutator 9 of the armature 6, and then through the terminal hook 9011 to the 10 turns of the armature wire. Finally, it is transmitted through the negative carbon brush 13 to the rear cover 2 to ground, forming a circuit.

[0036] After being energized, the 10 turns of the armature wire are subjected to Ampere force in the magnetic field generated by the permanent magnet stator 3, generating a continuous electromagnetic torque based on the principle of electromagnetic induction, driving the entire armature 6 to rotate around its axis. The rotating armature 6 transmits the torque directly to the drive gear 5, which meshes with it, through the spur spline at the front end of its shaft. The drive gear 5 drives the engine flywheel, which meshes with it horizontally, to rotate, thereby completing the ignition and starting task.

[0037] During this process, due to the adoption of the end-face commutator 9 structure and the thinner wire diameter of the armature wire 10, the electrical spark at the contact surface between the commutator segment 901 and the carbon brush is significantly reduced. This not only reduces carbon brush wear but also effectively extends the overall service life of the starter. At the same time, the direct-drive transmission structure eliminates the need for traditional electromagnetic switches and one-way switches, making the overall structure simpler and more reliable, and significantly reducing manufacturing costs.

[0038] Example 2 Based on Embodiment 1, this embodiment further defines the specific winding path of the armature wire 10 to explain its implementation in detail. The 16 slots 801 on the armature core 8 are sequentially labeled a1 to a16, and the 16 hooks 9011 on the end face commutator 9 are sequentially labeled b1 to b16.

[0039] The specific winding path of the armature wire 10 is as follows: The starting end of the armature wire 10 is first fixed to the connector hook 9011b1, then it passes through the wire groove 801a5 in a counterclockwise direction and exits from the wire groove 801a1. It is wound back and forth 4 times between the wire groove 801a1 and a5 to form a coil unit. After completing this unit, the armature wire 10 is wrapped around and fixed to the next connector hook 9011b2. Then, starting from the connector hook 9011b2, it passes through the wire groove 801a6 in a counterclockwise direction and exits from the wire groove 801a2. It is wound 4 times between the wire groove 801a2 and a6. After that, the armature wire 10 is wrapped around and fixed to the connector hook 9011b3.

[0040] Following this pattern, the armature wire 10 always follows the rule of "starting from the current hook 9011, passing through the far end slot 801 with a spacing of 4 slots, exiting from the adjacent near end slot 801, winding 4 turns, and then fixing to the next sequential hook 9011". It passes through hook 9011b4 and slots 801a7 and a3, hook 9011b5 and slots 801a8 and a4, etc., until finally being fixed to hook 9011b16, and completing the winding between slots 801a16 and a4. In this way, using a continuous conductor, strictly following the rule of "slot span 1-5, commutator segment 901 distance 1-2", it is wound in sequence for two rounds, and finally forms a total of 16 turns of coil in each slot 801, and establishes a one-to-one and reliable electrical connection with all 16 hooks 9011.

[0041] The above winding path clearly defines the spatial positional relationship and electrical connection structure between the armature wire 10, the wire groove 801, and the connecting hook 9011, which is the key to realizing the compact structure and excellent performance of the armature 6 of this utility model.

[0042] Based on the specific structures and processes described in Embodiments 1 and 2, the beneficial effects brought about by this utility model are specifically realized: By replacing the traditional radial commutator with the end-face commutator 9 and integrating it with the armature shaft 7 at the same axial end, the axial length of the armature 6 is effectively shortened, making the overall structure of the starter more compact. This also directly reduces the amount of copper used in the commutator segments 901, lowering material costs. By using a single continuous armature wire 10 and strictly adhering to the rule of "slot span 1-5, commutator segment 901 spacing 1-2" for winding, manual winding of the coil is achieved, eliminating the need for specialized winding equipment and tooling. Furthermore, the connection method of winding the armature wire 10 and the commutator segment 901 hooks 9011 with soldering replaces the traditionally required specialized spot welding equipment, greatly simplifying the welding process. These two points combined significantly reduce the manufacturing cost of the armature 6 and the reliance on specialized equipment.

[0043] At the overall machine level, by adopting a permanent magnet stator 3 for excitation and a spur spline direct drive transmission structure at the front end of the armature shaft 7, complex components such as electromagnetic switches and one-way switches in traditional starters are eliminated. This not only significantly reduces the number of parts and simplifies the overall structure, but also optimizes the assembly process, significantly improving production efficiency and reducing the overall cost. Meanwhile, the modular integrated brush holder assembly design forms a single unit with the rear cover 2, further simplifying the assembly process and improving structural reliability.

[0044] Furthermore, due to the small diameter (1mm) of the armature wire 10, its operating resistance is relatively high, resulting in a smaller normal operating current. Combined with the tight contact between the commutator segment 901 and the carbon brush under the tension of the spring 14, this significantly reduces the electrical sparks generated during commutation, effectively reducing carbon brush wear and extending the overall service life of the starter. The knurled structure at the fit between the armature shaft 7, the armature core 8, and the end face commutator 9 enhances the reliability of the interference fit and prevents relative rotation. The combined application of slot insulating paper 802, slot wedge 803, insulating end plate 24, and the sealing epoxy coating ensures reliable insulation between the coil and the core, as well as between the coils themselves, effectively preventing wire slippage caused by centrifugal force during high-speed operation of the armature 6, thus improving the product's structural stability and operational reliability.

[0045] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0046] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0047] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.

Claims

1. A direct-drive starter with an end-face commutator, comprising a front cover (1), a rear cover (2), a permanent magnet stator (3), a housing (4), and a drive gear (5), wherein the permanent magnet stator (3) is disposed inside the housing (4), characterized in that: It also includes an armature (6) disposed inside the permanent magnet stator (3); The armature (6) has an armature shaft (7), on which an armature core (8) and an end face commutator (9) are installed in sequence. The armature core (8) has a plurality of grooves (801) arranged along its circumference on its circumferential surface. The end face commutator (9) includes a base and a plurality of commutator segments (901) fixed on the base and arranged circumferentially. Each commutator segment (901) has a terminal hook (9011) formed by axial bending of an armature shaft (7) at its end. The armature (6) is also provided with a continuously wound armature wire (10), which is wound back and forth in the wire groove (801) to form a multi-turn coil, and the armature wire (10) includes a start end, an end end and a plurality of intermediate ends, which are respectively wound and fixed on different wire hooks (9011).

2. The end-face commutator direct-drive starter according to claim 1, characterized in that: A brush holder assembly is fixedly mounted on the rear cover (2) by connecting screws (15); The brush holder assembly includes a brush holder base plate (11), a positive carbon brush (12), a negative carbon brush (13) mounted on the brush holder base plate (11), and a compression spring (14) that provides pressure to the positive carbon brush (12) and the negative carbon brush (13). The brush holder base plate (11) serves as the base of the brush holder assembly and is directly fixed to the rear cover (2) by the connecting screws (15).

3. The end-face commutator direct-drive starter according to claim 1, characterized in that: The front end of the armature shaft (7) is fixedly mounted with a drive gear (5); the front end of the armature shaft (7) is also provided with a retaining ring groove (16), and a shaft retaining ring (17) is fitted into the retaining ring groove (16).

4. The end-face commutator direct-drive starter according to claim 1, characterized in that: Insulating end plates (24) are respectively fastened to both ends of the armature core (8) along the axial direction.

5. The end-face commutator direct-drive starter according to claim 1, characterized in that: The starting end, ending end, and intermediate connecting parts of the armature wire (10) are fixed to the connection hook (9011) by soldering.

6. The end-face commutator direct-drive starter according to claim 2, characterized in that: The rear cover (2) is also provided with a wiring stud (18), which passes through a pre-set stud hole on the rear cover (2) and is fixed by a nut (19) at the protruding part; an insulating block (20) is sleeved between the wiring stud (18) and the stud hole of the rear cover (2).

7. The end-face commutator direct-drive starter according to claim 1, characterized in that: The front cover (1) is equipped with a needle roller bearing (21) and a skeleton oil seal (22).

8. The end-face commutator direct-drive starter according to claim 7, characterized in that: A limiting gasket (23) is also provided between the front end of the armature shaft (7) and the front cover (1).

9. The end-face commutator direct-drive starter according to claim 1, characterized in that: Each of the slots (801) of the armature core (8) is covered with slot insulating paper (802) on its inner wall, and a slot wedge (803) is also embedded in the slot (801).

10. The end-face commutator direct-drive starter according to claim 9, characterized in that: The slot wedge (803) is made of an insulating rigid plate.

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