JP6017969B2 - Operating angle measuring device and operating angle measuring method for variable valve timing mechanism - Google Patents

Description

  The present invention relates to an operating angle measuring device and an operating angle measuring method for measuring an operating angle of a variable valve timing (VVT) mechanism.

  Patent Document 1 discloses a control position detection device for a variable valve operating device. In Patent Literature 1, a driven gear supported on one end of a control shaft and a drive gear supported on an end of a rotating shaft of an actuator are engaged with each other to form a reduction gear. When the rotation shaft of the actuator rotates, the rotation is decelerated and transmitted to the control shaft, and the rotation position of the control shaft changes within a predetermined rotation range limited by the stopper.

  When the control shaft is rotationally driven by the actuator via the gear, the rocking fulcrum of the rocker arm is changed, and the lift characteristic of the engine valve is changed. The detection device is provided with a gear sensor that detects the teeth of the driven gear in a non-contact manner. The control shaft rotation position (operating angle) is detected by measuring the number of gear teeth.

  Patent Document 2 discloses a gear backlash measuring device. The rotation detection gear is energized and meshed with the gear to be measured without backlash, and the idling amount or rotation angle delay of the measurement target is obtained from the output signal of the rotation sensor attached to the rotation shaft of the rotation detection gear. . The technique described in Patent Document 2 is not a technique for measuring the operating angle of the VVT mechanism.

JP 2001-82191 A Japanese Patent Application Laid-Open No. 08-2477842

  In Patent Document 1, the operating angle is detected by meshing the driven gear for detecting the operating angle with the control gear for VVT. As described above, in Patent Document 1, there is a problem that backlash is necessary to mesh the gears, and it is difficult to accurately measure the operating angle.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an operating angle measuring device and an operating angle measuring method capable of accurately measuring the operating angle of the variable valve timing mechanism. .

  An operating angle measuring apparatus according to a first aspect of the present invention measures a movable part having a protrusion fitted to a gear constituting a variable valve timing mechanism, and rotation of the movable part that rotates as the gear rotates. And measuring means for calculating the operating angle of the gear based on a measurement value obtained by the measuring means.

  In the operating angle measuring device according to the second aspect of the present invention, in the above operating angle measuring device, the measuring means transmits the rotation of the movable part, the first pulley, and the rotation of the first pulley is operated. And a second pulley that transmits the angle to the angle calculating means, and the speed increasing ratio of the first pulley to the second pulley is 1 or more.

  In the operating angle measuring method according to the third aspect of the present invention, the protrusion of the movable part is fitted to the gear constituting the variable valve timing mechanism, the rotation of the movable part accompanying the rotation of the gear is measured, and the movable part The operating angle of the gear is calculated based on the measured value of the rotation.

  The operating angle measuring method according to a fourth aspect of the present invention is the operating angle measuring method described above, wherein the rotation of the movable part is transmitted to the first pulley, and the rotation of the first pulley is increased by a speed increasing ratio of 1 or more. To the second pulley, and the measurement value is obtained based on the rotation of the second pulley.

  According to the present invention, it is possible to provide an operating angle measuring device and an operating angle measuring method capable of accurately measuring the operating angle of the variable valve timing mechanism.

It is a figure which shows the structure of the working angle measuring apparatus which concerns on embodiment. It is the figure which looked at the working angle measuring apparatus shown in FIG. 1 from the side. It is a figure for demonstrating the problem in the working angle measurement of a VVT mechanism. It is the perspective view which expanded the part shown with the dashed-dotted line of FIG. It is the figure which looked at FIG. 4 from the top.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description explains the embodiment of the present invention, and the present invention is not limited to the following embodiment. For clarity of explanation, the following description is omitted and simplified as appropriate. Moreover, those skilled in the art can easily change, add, and convert each element of the following embodiments within the scope of the present invention.

  First, with reference to FIGS. 3 to 5, problems in measuring the operating angle of a VVT (Variable Valve Timing) mechanism will be described. FIG. 3 is a diagram showing an example of an operating angle measuring device for the VVT mechanism. 4 is an enlarged perspective view of a portion indicated by a one-dot chain line in FIG. FIG. 5 is a top view of FIG.

  The VVT mechanism adjusts the operating angle of an intake valve and an exhaust valve of an automobile engine by twisting a camshaft with respect to a cam pulley, and changes the opening / closing timing of the valve according to the engine speed. The VVT mechanism includes a valve timing adjusting device, an OCV (Oil Control Valve), an oil pump, an ECU (Engine Control Unit), and the like.

  The rotor of the valve timing adjusting device is provided with a retard chamber and an advance chamber. When oil is introduced into the retarding chamber, the hydraulic pressure causes the camshaft to move in the opposite direction to the rotational direction, thereby delaying the valve opening timing. On the other hand, when the oil is guided to the advance chamber, the camshaft moves in the rotational direction, and the valve opening timing is advanced. The operating angle of the valve timing adjusting device is set according to the vehicle to be mounted.

  The operating angle measuring device measures the operating angle of the valve timing adjusting device. As shown in FIGS. 3 and 4, a valve timing adjusting device (hereinafter referred to as a workpiece) 10 to be measured includes a gear 11, a housing 12, a rotor 13, and a lock pin 14. As shown in FIG. 4, when the opening timing of the valve is delayed, the gear 11 and the housing 12 rotate to the retard side. When the opening timing of the valve is advanced, the gear 11 and the housing 12 rotate to the advance side.

  The workpiece 10 is placed on the fixed jig 31. The rotor 13 of the workpiece 10 is clamped by the robot arm 30 and fixed to the fixing jig 31. Air is supplied from the fixing jig 31 to the workpiece 10. The lock pin 14 rises when a certain pressure is applied by the air supplied from the fixing jig 31. When the lock pin 14 is completely removed, the gear 11 and the housing 12 can rotate with respect to the fixing jig 31.

  The rotating jig 32 is rotated by a motor or air drive. In the example shown in FIG. 3, the driving force from the motor 33 is transmitted to the rotary jig 32 via a transmission gear 34 composed of two meshed gears. That is, when the motor 33 is driven, the driving force is transmitted to the rotary jig 32 by the transmission gear 34, and the rotary jig 32 rotates.

  As shown in FIGS. 4 and 5, the rotary jig 32 has a configuration in which a plurality of lattices 35 are arranged on the circumference. It arrange | positions so that the grating | lattice 35 of the rotary jig 32 and the teeth of the gear 11 may mesh. Therefore, the gear 11 rotates as the rotary jig 32 rotates. An encoder 36 is connected to the rotary jig 32. The encoder 36 measures the operating angle from the rotational displacement of the rotary jig 32.

  At this time, there is a case where the lattice 35 is worn and rattle occurs at a portion where the lattice 35 and the gear 11 shown by a broken line ellipse in FIG. Since the operating angle is measured for all the valve timing adjusting devices, the wear of the portion of the rotary jig 32 that meshes with the gear 11 is particularly severe and there is a problem that the operating angle cannot be measured accurately.

  In addition, as shown in FIG. 5, there is a gap (backlash) intentionally provided in the movement direction for rotation between the teeth of the gear 11 and the lattice 35 of the rotary jig 32. For this reason, the operating angle may not be measured more accurately.

  Therefore, the present inventors have devised an operating angle measuring device having a configuration as shown in FIGS. FIG. 1 is a diagram illustrating a configuration of an operating angle measurement device 1 according to an embodiment. FIG. 2 is a side view of the operating angle measuring apparatus 1 shown in FIG. As shown in FIG. 1, the operating angle measuring device 1 measures the operating angle of the workpiece 10. As described above, the workpiece 10 is a valve timing adjusting device, and includes a gear 11, a housing 12, a rotor 13, a lock pin 14, and the like as shown in FIG.

  As shown in FIGS. 1 and 2, the operating angle measurement device 1 includes a movable portion 20, a pulley 23, a timing belt 24, a pulley 25, and a rotary encoder 26. The movable part 20 has a protrusion 21 and an actuator 22. The protrusion 21 is a member that fits into the gear 11 of the workpiece 10. The protrusion 21 is pressed against the gear 11 by the actuator 22.

  The movable part 20 swings with the rotation of the gear 11 of the workpiece 10. A pulley 23 is coupled to the movable portion 20. As shown in FIG. 2, one end of the movable portion 20 is fixed to the pulley 23, and the pulley 23 rotates with the rotation of the movable portion 20.

  The timing belt 24 is a toothed belt used for transmitting rotation between two parallel axes. In the present embodiment, the timing belt 24 transmits the rotation of the pulley 23 to the pulley 25. That is, in the present embodiment, the pulley 23, the timing belt 24, and the pulley 25 serve as measurement means. Note that the measuring means is not limited to this configuration. For example, a chain, a sprocket, or the like can be used as the measuring means.

  A rotary encoder 26 is coupled to the pulley 25. The rotary encoder 26 is an operation angle calculation unit that generates a pulse corresponding to the rotation angle of the rotation shaft as a pulse train, and calculates the rotation angle (operation angle) of the rotation shaft by counting the pulse train.

  As described above, the operating angle measuring device 1 according to the embodiment can measure the operating angle in a state where the protrusion 21 is pressed against the gear 11 and the backlash is eliminated. For this reason, as described with reference to FIGS. 3 to 5, it is possible to accurately measure the operating angle of the valve timing adjusting device regardless of the wear and backlash of the lattice.

  Further, the speed increasing ratio (rotation ratio) of the pulley 23 to the pulley 25 is preferably 1 or more. That is, the gear ratio between the pulley 23 and the pulley 25 is preferably 1 or more. For example, it is assumed that the speed increasing ratio between the pulley 23 and the pulley 25 is 2. That is, the ratio of the number of teeth of the pulley 23 and the number of teeth of the pulley 25 is 2: 1. That is, the pulley 25 rotates twice while the pulley 23 rotates once.

  Since the rotary encoder 26 outputs a pulse every time the rotating shaft rotates by a certain amount, the number of pulses to be output increases as the rotation angle of the pulley 25 increases. In the above example, the number of pulses output from the rotary encoder 26 is doubled. Thereby, it becomes possible to improve the resolution of the measurement of the operating angle.

  As described above, in this embodiment, since the operating angle is measured in a state where the gear 11 is directly clamped and the backlash is eliminated, the operation check of the finished product of the VVT mechanism, the check of defective products, etc. In the quality assurance process, it is possible to minimize the measurement error of the equipment and accurately measure the operating angle of the product. Further, since the operating angle is transmitted to the rotary encoder 26 by using the pulley 23 and the pulley 25 having a speed increasing ratio of 1 or more, the measurement resolution can be improved. As a result, as described with reference to FIGS. 3 to 5, it is possible to accurately measure the operating angle of the valve timing adjusting device regardless of grid wear or backlash.

  Note that the present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

1 Working angle measuring device 10 Workpiece (valve timing adjusting device)
DESCRIPTION OF SYMBOLS 11 Gear 12 Housing 13 Rotor 14 Lock pin 20 Movable part 21 Protrusion 22 Actuator 23 Pulley 24 Timing belt 25 Pulley 26 Rotary encoder 30 Robot arm 31 Fixing jig 32 Rotating jig 33 Motor 34 Transmission gear 35 Grid 36 Encoder

Claims (4)

Have a protrusion that fits into a gear constituting the variable valve timing mechanism, in a state in which the projection is fitted to the gear, and a movable portion that swings around the rotation axis of the gear with the rotation of the gear ,
Measuring means for measuring the oscillation of the front Symbol movable portion,
An operating angle calculating means for calculating an operating angle of the gear based on a measured value by the measuring means;
An operating angle measuring device comprising: The measuring means includes
A first pulley for transmitting the swing of the movable part;
A second pulley for transmitting the rotation of the first pulley to the operating angle calculating means;
Have
The operating angle measuring device according to claim 1, wherein a speed increasing ratio of the first pulley to the second pulley is 1 or more. The protrusion of the movable part is fitted to the gear constituting the variable valve timing mechanism, and the movable part is swung around the rotation axis of the gear as the gear rotates,
Measuring the oscillation of the movable portion,
Based on the measured value of the swing of the movable part, the operating angle of the gear is calculated.
Working angle measurement method. Transmitting the swing of the movable part to the first pulley;
Transmitting the rotation of the first pulley to a second pulley having a speed increasing ratio of 1 or more;
Obtaining the measured value based on rotation of the second pulley;
The operating angle measuring method according to claim 3.

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