Patent Application
20200095967
The present disclosure relates to electric motors for automotive vehicles, in particular starter motors for starting an internal combustion engine.
Vehicles equipped with internal combustion engines include an electric starter that is operable to start the engine. Electric starters may be electro-mechanical, in that they may include an electric motor that receives current from a battery to cause a mechanical output, e.g., rotating a gear to crank the engine. For various reasons, the starter motor may not crank the engine because the electric motor, the gear, or both may not rotate.
According to one embodiment, a starter motor assist mechanism is provided. The starter motor assist mechanism may include a housing, a solenoid, and a hammer. The housing may be attachable to a starter motor. The solenoid may be disposed within the housing, and the hammer may be connected to the solenoid. The solenoid may move the hammer from a retracted position to an extended position for striking the starter motor.
According to another embodiment, a vehicle starting system is provided. The vehicle starting system may include a starter motor that includes a casing defining a yoke that surrounds an armature. The starter motor may be configured to engage and start an engine. The vehicle starting system may also include a starter-assist device that may be mounted to the casing of the starter motor. The starter-assist device may include a housing, a solenoid that may be disposed within the housing, and a hammer that may be operatively connected to the solenoid. When the solenoid is powered, the hammer may move from a retracted position to an extended position to strike the yoke.
According to yet another embodiment, a starter-motor-assist system is provided. The starter-motor-assist system may include a starter motor, a first solenoid, a starter-assist mechanism, and a controller. The starter motor may be configured to rotate and start an engine. The starter motor may include a casing that surrounds an armature of the starter motor. The first solenoid may be mechanically connected to the starter motor and configured to close a set of contacts to provide power to the starter motor. The starter-assist mechanism may include a second solenoid and a hammer that may be operatively coupled to the second solenoid. The hammer may be moveable from a retracted position to an extended position to strike the casing. The controller may be configured to, responsive to the first solenoid closing the set of contacts and the starter motor not rotating, send a signal to provide power to the second solenoid so that the hammer strikes the casing to facilitate rotation of the starter motor.
Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
Internal combustion engines generally include an electric starter motor that includes a rotating gear used to rotate (crank) the internal-combustion engine to initiate the engine's operation under its own power. Generally, starter motors include an armature that rotates in response to an electric current provided through an adjacent electric field coil. The starter motor may include a solenoid that provides electric current to the field coil. The armature may be coupled to a shaft that includes a drive gear. The drive gear may engage one or more gears so that rotation of the drive gear causes rotation of a pinion gear. In some electric motors, one or more gears may translate or slide in a longitudinal direction so that the pinion gear engages the engine.
Under certain circumstances, the armature may not rotate, or the shaft may not translate (e.g., axial or linearly), thus causing a no-start condition. As one example, one or more brushes within the electric motor may stick, thus causing a stuck brush condition, and preventing rotation of the armature. A stuck brush may be due to carbon build up, oxidation, corrosion, or some combination thereof. As another example, corrosion of the starter housing or one or more internal components may cause an accumulation of rust or debris within the casing. This debris may prevent rotation of the electric motor, one or more of the gears, or translation of one or more of the shafts of the motor. Striking the housing of the starter motor with a tool, e.g., hammer, wrench, or other blunt instrument may dislodge the debris or dislodge a stuck brush. While this resolves the issue, the operator of the vehicle may be required to tow it to a vehicle service provider so that the condition is resolved, either by replacement of the starter motor or the method described above. Alternatively, the operator may be forced to exit the vehicle, locate the starter motor by crawling underneath the vehicle, and hit or strike the starter motor as described above. This disclosure attempts to provide an alternative solution to the above-mentioned problems.
Referring to
In one embodiment, the controller 18 may be configured to send a signal to power the starter-assist mechanism 104 in response to the ignition switch 20 being in the start position 24 and the presence of a no-start condition.
In another embodiment, a starter-assist button 26 may be provided. The starter-assist button 26 may be actuated so that power is provided and the starter-assist mechanism 104 is actuated.
As shown in
The starter-assist mechanism 104 may include a starter-assist solenoid 118 that is provided with terminals 120 that may be electrically connected (e.g., directly or indirectly) to the battery 14. A hammer 122 may be coupled to the starter-assist solenoid 118 so that it is moveable from a retracted position to an extended position, along the bi-directional arrow D (
The hammer 122 may strike or hit the starter casing with a predetermined force ranging between 50 N and 500 N. The predetermined force may depend on one of several factors, including but not limited to, the size, shape, thickness, and material type of the starter casing 106. For example, larger engines for trucks and the like require larger starter motors and in turn, larger casings, whereas starter motors for smaller passenger cars may include smaller starter motors and smaller starter casings. More force may be required for the larger starter motors than those starter motors for smaller vehicles. The predetermined force may be selected for the size and shape of the starter motor. Another determining factor of the predetermined force may be the expected amount of corrosion or deterioration of the starter casing and the internal components housed therein.
In addition to the force applied by the hammer, the frequency of the strikes made by the hammer 122 may be altered by the controller 18. Frequency refers to the number of movements occurring with a fixed period and may be described in hertz (Hz). The frequency of the strikes may range between a relatively low frequency, such as 1 Hz, to an ultrasonic frequency, such as 20,000 Hz. Increasing the frequency of the strikes may create one or more vibrations through starter motor 102, which may loosen or dislodge a stuck brush or debris more effectively than a lower frequency.
The starter casing 106 may be made of a stamping comprised of one or more materials (e.g., steel, aluminum, an alloy, or other suitable materials). Due to fuel efficiency and emissions concerns, the thickness of the starter casing may be kept to a minimum to conserve weight. To prevent damage to the casing 106, such as denting or fractures, the hammer 122 may include a dampening member 123 that acts as a barrier between the hammer and the starter casing 106. The dampening member 123 may be comprised of an elastomeric material, such as rubber or a polymeric material, that is adhered to the hammer 122. Alternatively, the dampening member 123 may be over-molded over the hammer 122.
A mounting bracket 124 may be attached to the starter-assist solenoid 118 and the starter casing 106. The mounting bracket 124 may have a medial portion 126 and attachment portions 128 that are spaced apart from the medial portion 126 so that the starter-assist solenoid is spaced apart from the starter casing 106 by a distance Hi. The attachment portions 128 of the mounting bracket 124 may define attachment apertures 130 through which a fastener may extend to engage the starter casing 106.
Referring specifically to
The electromagnetic force acting upon the plunger 142 causes the plunger 142 and the hammer 122 to move or translate from the retracted position to the extended position. In the retracted position, the hammer 122 may be adjacent to the bottom portion 136 of the housing 134. In the extended position, the hammer 122 contacts with starter casing 106. A return spring 148 may bias or return the hammer 122 from the extended position to the retracted position when the solenoid 118 is deactivated or when a force applied by the return spring 148 is greater than the force applied by the solenoid 118. The return spring 148 may be disposed between the bottom portion 136 of the housing 134 and a bottom portion 150 of the plunger 142, as shown. Alternatively, the return spring 148 may be positioned against a top portion 152 of the housing 134 and the other end may be engaged or attached to the plunger 142.
In one or more embodiments, the starter-assist mechanism 104 may be connected to or attached to the starter solenoid 103. Under certain circumstances, the starter solenoid 103 may not be electrically connected to the starter motor 102. For example, debris (e.g., ice or solid corrosion) may be disposed on the contacts of the starter solenoid 103, thus preventing a flow of current from the starter solenoid 103 to the starter motor 102. The starter-assist mechanism 104 may then be actuated so that the hammer 122 strikes the starter solenoid 103 to displace the debris from the contacts of the starter solenoid 103.
In another embodiment, straps 230 or clamps 232 may attach the mounting bracket 124 to the casing 106 of the starter motor 102, as shown in
Control logic or functions performed by the controller 18 may be represented by flow charts or similar diagrams, such as the flow chart 500 in
The controller 18 may include a microprocessor or central processing unit (CPU) in communication with various types of computer readable storage devices or media. Computer readable storage devices or media may include volatile and nonvolatile storage in read-only memory (ROM), random-access memory (RAM), and keep-alive memory (KAM), for example. KAM is a persistent or non-volatile memory that may be used to store various operating variables while the CPU is powered down. Computer-readable storage devices or media may be implemented using any of a number of known memory devices such as PROMs (programmable read-only memory), EPROMs (electrically PROM), EEPROMs (electrically erasable PROM), flash memory, or any other electric, magnetic, optical, or combination memory devices capable of storing data, some of which represent executable instructions, used by the controller in controlling the starter-assist mechanism 104 and starter motor 102.
Although not always explicitly illustrated, one of ordinary skill in the art will recognize that one or more of the illustrated steps or functions may be repeatedly performed depending upon the particular processing strategy being used. Similarly, the order of processing is not necessarily required to achieve the features and advantages described herein, but is provided for ease of illustration and description. The control logic may be implemented primarily in software executed by a microprocessor-controlled vehicle, engine, and/or powertrain controller, such as controller 18.
Of course, the control logic may be implemented in software, hardware, or a combination of software and hardware in one or more controllers depending upon the particular application. When implemented in software, the control logic may be provided in one or more computer-readable storage devices or media having stored data representing code or instructions executed by a computer to control the vehicle or its subsystems. The computer-readable storage devices or media may include one or more of several known physical devices that utilize electric, magnetic, and/or optical storage to keep executable instructions and associated calibration information, operating variables, and the like.
In operation 502, the ignition switch 20 is placed in the start position 24 so that electric current is provided from the battery 14 to the starter solenoid 103, as represented by operation 504. If the starter motor 102 actuates and cranks the engine 12, the process ends at operation 520. On the other hand, if the starter motor 102 does not actuate and a no-start condition occurs, the controller 18 may provide a signal to actuate the starter-assist mechanism 104, as represented by operation 510.
Alternatively, the controller may not be programmed to actuate the starter-assist mechanism 104, and an operator of the vehicle may actuate the starter-assist button 26, as represented by operation 508. Actuating the starter-assist button may send a signal to the controller 18 to actuate the starter-assist mechanism 104, as represented again by operation 510. In operation 510, the starter-assist mechanism is powered and translates the hammer 122 to strike the starter casing 106 one or more times at a predetermined force and at a predetermined frequency. The predetermined frequency refers to the number of times the hammer is moved from the retracted position to the extended position with respect to a predetermined period. The term predetermined period means a fixed set of time.
After operation 510, the controller 18 may branch to determine or detect whether a second no-start condition occurs, as represented by operation 512. If the engine starter motor actuates, the process ends at 520. If the starter motor has not actuated, the controller may branch to operation 514 to increase the force applied by the hammer 122 to the starter casing 106. In addition to or in lieu of increasing the force applied by the hammer, the controller may also increase number of hits, as represented by operation 516. Moreover, the frequency of the hits may be altered (e.g., increased or decreased) at operation 518.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, to the extent any embodiments are described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics, these embodiments are not outside the scope of the disclosure and can be desirable for particular applications.
