Valve timing controller

#This application is based on and claims priority under 35 U.S.C. § 119 to Japanese Patent Application 2020-072305, filed on Apr. 14, 2020, the entire content of which is incorporated herein by reference.

#This disclosure relates to a valve timing controller that controls a valve opening and closing timing of an internal combustion engine by a driving force of a brushless motor.

#In the related art, a valve timing controller capable of changing the opening and closing timing of an intake valve or an exhaust valve according to an operating condition of an internal combustion engine (hereinafter, also referred to as “engine”) has been used. The valve timing controller has a mechanism to change the opening and closing timing of the intake valve or the exhaust valve by changing the relative rotation phase (hereinafter, also simply referred to as “relative rotation phase”) of a driven-side rotation member with respect to the rotation of a driving-side rotation member due to the operation of the engine. In recent years, idling stop control for temporarily stopping the engine, for example, when stopping the vehicle by stepping a brake pedal during the normal operation has been put into practical use. In a case where the restart is quick, such as when the idling is stopped, the valve timing controller needs to keep the relative rotation phase at the most retarded angle in order to reduce the load on the engine and prepare for the restart. However, it is not easy to maintain the relative rotation phase at the most retarded angle due to an external force such as pressure in the cylinder acting on a camshaft when restarting the engine that has stopped idling. Therefore, it is considered to lock the motor when the engine is restarted. As a technique used to lock such a motor, for example, there is a technique described in JP 2007-228768A (Reference 1) of which a source is illustrated below.

#The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with the reference to the accompanying drawings, wherein:

#FIG. 1 is a sectional view of a valve timing controller;

#FIG. 2 is a view illustrating a configuration of a motor and an inverter;

#A valve timing controller according to the present disclosure is configured to suppress deterioration or damage of the element even in a case where the brushless motor is locked. Hereinafter, a valve timing controller 100 of this embodiment will be described.

#FIG. 1 is a sectional view of a valve timing controller 100, and FIG. 2 illustrates a configuration of a brushless motor (hereinafter, referred to as “motor”) M of the valve timing controller 100 and an inverter 40 for driving the motor M. As illustrated in FIGS. 1 and 2, the valve timing controller 100 includes a driving case (an example of a “driving-side rotation member”) 10, an internal rotor (an example of a “driven-side rotation member”) 20, a phase setting mechanism 30, the motor M, the inverter 40, a control portion 50, a command information acquisition section 60, a temperature detecting section 70, and a map storage section 80. In particular, the control portion 50, the command information acquisition section 60, and the map storage section 80 are constructed with hardware, software, or both the hardware and the software with a CPU as a core member in order to perform processing related to suppression of deterioration or damage of elements.

#The driving case 10 rotates synchronously with respect to a crankshaft 1 of an internal combustion engine E. The internal combustion engine E has an intake valve Va of which the opening and closing timing is controlled by the valve timing controller 100. The crankshaft 1 corresponds to an output shaft that outputs a rotational force from the internal combustion engine E. A drive pulley 11 is provided on the outer peripheral surface of the driving case 10, and a timing belt 6 is wound around an output pulley 1S of the crankshaft 1. Accordingly, the driving case 10 can rotate synchronously with respect to the crankshaft 1.