JPH06137999A - Performance measuring device of valve timing control mechanism - Google Patents

Abstract

PURPOSE:To prevent generation of wear, etc., of component parts and at the same time to improve performance measurement working efficiency while reducing drive noise and miniaturizing a device. CONSTITUTION:The title device converts the relative rotation phase between a timing sprocket 22 and a cam shaft by the movement of a cylindrical gear 26 in axial direction. An inertia circular plate 41 is fixed to a gear part 29 of the timing sprocket 22 and at the same time a rotary actuator 42 for generating forward and backward torsion vibration is provided at a drive shaft 23, thus creating positive and negative rotary torque fluctuation in the cylindrical gear 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve timing control mechanism performance measuring apparatus for variably controlling the opening and closing timings of intake and exhaust valves in accordance with engine operating conditions.

[0002]

As is well known, internal combustion engines for automobiles are
Some have a valve timing control mechanism that variably controls the opening and closing timings of the intake valve and the exhaust valve. This valve timing control mechanism generally includes a timing sprocket driven by an engine, a cam shaft that opens an intake / exhaust valve against the spring force of a valve spring by the rotational force transmitted from the timing sprocket, and the cam. A tubular gear is provided between one end of the shaft and a tubular main body of the timing pulley facing the one end. The cylindrical gear moves in the axial direction of the camshaft through hydraulic pressure and spring force of a compression spring while the helical teeth have inner and outer teeth meshing with the inner teeth of the cylindrical body and the outer teeth of one end of the camshaft, respectively. By doing so, the relative rotational phase of the timing pulley and the cam shaft is converted. By this, intake,
The opening / closing timing of the exhaust valve is variably controlled according to the engine operating state.

By the way, in such a valve timing control mechanism, the performance of the axial gear movement response of the cylindrical gear is measured while considering the rotational torque fluctuation acting on the camshaft before it is assembled to the internal combustion engine. ing.

That is, as this conventional performance measuring apparatus,
For example, as shown in FIGS. 3 to 4, a DOHC type valve operating mechanism 3 of a so-called dummy multi-cylinder internal combustion engine 2 fixed on a base 1.
Install the valve timing control mechanism 4 in advance,
The crankshaft 2a of the internal combustion engine 2 is rotationally driven by the electric motor 6 via the transmission belt 5.

By the drive of the electric motor 6, the rotational force is transmitted from the crankshaft 2a to the camshaft 8 via the timing pulley 7, and the lift force of the cam 8a and the spring force of the valve spring 9 cause the valve lifter 13 to move.
While the intake valve 10 is opened and closed via the solenoid valve control mechanism 4, the valve timing control mechanism 4 operates the solenoid gear switching valve 11 to move the tubular gear to the O-position by the hydraulic pressure in the pressure chamber or the spring force of the compression spring.
By moving the camshaft axially in the N-OFF direction, the relative rotational phase of the timing pulley 7 and the camshaft 8 is converted.

Here, as shown in FIG. 5, the camshaft 8 has positive and negative (+,-) caused by the spring reaction force of the valve spring 9 when the intake valve 10 is opened and closed, that is, immediately before and after the cam 8a is lifted. ), The rotational torque fluctuation occurs, and this rotational torque fluctuation affects the axial mobility of the cylindrical gear.

Therefore, the control unit (not shown) includes the electromagnetic pickup type crank sensors 12 provided at one end of the camshaft 8 and the light transmitting slit disk 13 provided at the other end and the light emitting / receiving units 14 and 15. By inputting an output signal from a digital advance angle meter, etc., the axial movement response performance of the cylindrical gear is measured while considering the influence of positive and negative rotational torque fluctuations generated in the camshaft 8. Has become.

[0008]

However, in the above-mentioned conventional performance measuring apparatus, the normal valve operating mechanism 3 is incorporated in the engine 2 in order to generate the rotational torque fluctuation in the camshaft 8, and the engine 2 is operated. The electric motor 6 is rotationally driven. For this reason, a large driving noise of the electric motor 6 including the valve mechanism 3 is generated, and a device for ensuring safety during driving is required, which inevitably requires an increase in the size of the entire device. ing.

Further, wear and fatigue of the components due to rotation and operation during performance measurement cause the positive and negative rotational torque fluctuations of the camshaft 8 to become unstable, and the movement responsiveness of the cylindrical gears, etc. The performance cannot be measured with high accuracy.

Further, since the fluctuation of the rotation torque of the camshaft 8 changes depending on the number of cylinders and the number of rotations of the engine 2, the valve mechanism 3 and the engine 2 must be changed for each specification such as the change of the number of cylinders of the engine 2. However, the work becomes extremely complicated.

[0011]

The present invention has been devised in view of the actual situation of the above-mentioned conventional performance measuring device, and in particular, it controls the rotation of the rotating body and is provided at a position corresponding to the camshaft. It is characterized in that a rotary actuator for generating forward and reverse torsional vibrations is provided on the drive shaft.

[0012]

According to the present invention, the rotation torque fluctuation of the camshaft is not obtained from a normal valve mechanism, but the rotation is controlled by the drive shaft in which positive and negative torsional vibrations are generated by the rotary actuator and the inertia disk, for example. The positive and negative rotational torque fluctuations are given to the phase conversion means by the interaction with the rotating body.

As a result, positive and negative rotational torques are created without using an electric motor or valve mechanism as in the prior art, and the performance such as movement response of the phase conversion means can be measured in the same state as the actual machine.

[0014]

1 shows a first embodiment of a performance measuring apparatus for a valve timing control mechanism according to the present invention.

That is, the valve timing control mechanism 21 is
A drive corresponding to a camshaft having a timing sprocket 22, which is a rotating body to which a rotational driving force is transmitted by an engine through a timing chain, and a cam for opening and closing intake and exhaust valves by the rotational force transmitted from the timing sprocket 22. The shaft 23 and the drive shaft 23
A sleeve 25 fixed axially to the one end flange 23a via a fixing bolt 24, and a cylindrical gear 26 interposed between the sleeve 25 and the timing sprocket 22.

The timing sprocket 22 is provided with a front cover 28 at the front end opening of the cylindrical main body 27, and a gear portion 29 around which a timing chain is wound is integrally provided on the outer periphery of the rear end portion. Inner teeth are formed on the inner peripheral surface of the cylindrical main body 27.

The sleeve 25 has a flange 23 at the rear end.
A large-diameter flange portion 30 that is fitted to a and that rotatably supports the rear end side of the cylindrical main body 27 on the outer peripheral surface is provided integrally, and outer teeth are formed on the outer peripheral surface.

The cylindrical gear 26 is mainly composed of a front gear forming portion and a rear gear forming portion which are divided into two parts, and has helical gear-shaped inner and outer teeth which mesh with the inner and outer teeth on the inner and outer peripheral surfaces. 26a, 26b are formed, and the hydraulic pressure in the pressure chamber 31 on the front end side and the compression spring 32 on the rear end side are formed.
It moves in the axial direction of the drive shaft 23 by the relative pressure with. As a result, the timing sprocket 2
2 and the relative rotation phase of the drive shaft 23 are converted.

The hydraulic circuit 33 for supplying and discharging the hydraulic pressure to and from the pressure chamber 31 includes an oil passage 35 formed in a bearing block 34 corresponding to a cam bearing of a cylinder head, a bolt in the drive shaft 23 and the sleeve 25. An annular passage 36 formed between the insertion hole and the fixing bolt 24, one end of which communicates with the oil passage 35 and the other end of which communicates with the pressure chamber 31, and an oil passage 35.
Hydraulic unit 3 such as an oil pump provided at one end of the
7 and an electromagnetic switching valve 38 that switches the flow path of the oil passage 35.

Then, the performance measuring device has the gear part 29.
Is fixed via a bolt 39 and a retainer plate 40 to the inertial disk 41 that controls the rotation of the timing sprocket 22, that is, an inertial force is generated. Rotary actuator 42 for generating torsional vibration of the drive shaft 23
Detector 43 for detecting positive and negative rotational torque fluctuations of
And a dial displacement gauge (not shown) for detecting the angular displacement of the timing sprocket 22, and a control unit 44 for outputting a vibration control signal to the rotary actuator 42. The drive shaft 23 is provided with a coupling 45 for axial shake correction at a substantially intermediate position. Further, in the control unit 44, a built-in microcomputer outputs an arbitrary vibration control signal, for example, a vibration control signal of 100 HZ, to the rotary actuator 42 based on a feedback signal from the torque detector 43. At the same time, the angular displacement signal from the dial displacement gauge is measured on the time axis to calculate the axial movement time of the cylindrical gear 26.

Therefore, according to this embodiment, in order to measure the maximum moving time of the cylindrical gear 26 in the axial direction on one side (rightward in the figure), the control unit 44 previously outputs an arbitrary vibration control signal. Based on rotary actuator 4
2 applies forward and reverse torsional vibrations to the drive shaft 23. Therefore, a relatively large moment of inertia is generated in the inertial disk 41 due to such torsional vibration, and this moment of inertia acts on the cylindrical gear 26, and the large moment of inertia causes the valve gear to operate on the cylindrical gear 26. The same positive and negative rotational torque fluctuations occur as in the actual machine equipped with.

Here, an ON signal is output to the electromagnetic switching valve 38, and the cylindrical gear 26 receives the fluctuation of the rotational torque, and the compression spring 32 is supplied by the hydraulic pressure supplied to the pressure chamber 31 via the hydraulic circuit 33. Move to the right while compressing. This allows the timing sprocket 22
Is relatively rotated in one direction with respect to the drive shaft 23, and the control unit 44 calculates the moving time of the cylindrical gear 26 based on a signal from the dial displacement meter that detects the rotational angular displacement.

On the other hand, in order to measure the maximum moving time of the cylindrical gear 26 in the axial direction on the other side (left direction in the drawing), electromagnetic switching is performed while applying forward and reverse torsional vibrations to the drive shaft 23 as described above. An OFF signal is output to the valve 38 and the hydraulic pressure in the pressure chamber 31 is discharged to the outside via the hydraulic circuit 33. Therefore, the tubular gear 26 moves in the other maximum direction (leftward in the drawing) by the spring force of the compression spring 32 while being subjected to positive and negative rotational torque fluctuations. Therefore, the timing sprocket 22 relatively rotates in the other direction, and the control unit 44 calculates the return movement time of the tubular gear 26 based on a signal from the dial displacement gauge for the rotational angle displacement.

As described above, in this embodiment, the cylindrical gear 26
In addition, the inertial disk 41 and the rotary actuator 42 generate positive and negative rotational torque fluctuations similar to those of the valve mechanism through the drive shaft 23, and measure the movement time of the cylindrical gear 26, that is, the performance such as movement responsiveness. Therefore, compared to the case where the cam shaft is rotated using the conventional electric motor or valve operating mechanism, not only the drive noise is greatly reduced, but also safety is sufficiently secured, so that the stabilizer etc. It becomes unnecessary, and the overall size of the device can be reduced.

Further, it is possible to prevent wear and fatigue over time due to rotational sliding of each component, so that stable rotational torque fluctuations can always be obtained and highly accurate performance measurement can be performed.

Further, since the magnitude of the positive and negative rotational torque fluctuations can be arbitrarily set, it is not necessary to change the engine or the like each time, and the efficiency of the performance measuring operation can be improved.

FIG. 2 shows a second embodiment of the present invention, in which the gear portion 29 of the timing sprocket 22 is
It is fixed to the base B via an annular fixing member 47 and a bracket 46. The other structure is the same as that of the first embodiment.

Therefore, according to this embodiment, when the forward and reverse torsional vibrations are applied to the drive shaft 23 from the rotary actuator 42 by the vibration control signal from the control unit 44, the timing sprocket 22 is moved to the base B. Since it is fixed, positive and negative rotational torque fluctuations are directly generated in the cylindrical gear 26 by the torsional vibration of the drive shaft 23. Therefore, the tubular gear 26 moves in the left-right direction similarly to the above while receiving the positive and negative rotational torque fluctuations, and the movement time, that is, the movement responsiveness is calculated by the control unit 44.

Therefore, the same effects as those of the first embodiment can be obtained, and the cylindrical gear 26 is directly applied to the cylindrical gear 26 by the torsional vibration applied to the drive shaft 23 from the rotary actuator 42 without utilizing the inertial force. Since the rotational torque fluctuation is generated, it is possible to generate the rotational torque fluctuation with higher accuracy.

[0030]

As is apparent from the above description, according to the present invention, the rotary which controls the rotation of the rotating body and generates the forward and reverse torsional vibrations on the drive shaft provided at the position corresponding to the cam shaft. Since the actuator is provided to generate the positive and negative rotational torque fluctuations in the phase conversion means, the conventional valve operating mechanism, the electric motor for driving the valve operating mechanism, and the like are unnecessary. For this reason, driving noise can be greatly reduced, and a safety device is not required, so that the size of the entire device can be reduced.

Further, since the drive shaft is not rotated but only forward and reverse torsional vibrations are applied as described above, abrasion and fatigue with time due to rotational sliding of each component is prevented. As a result, stable rotational torque fluctuations can always be obtained, and highly accurate performance measurement of the valve timing control mechanism becomes possible.

Further, since the magnitude of the positive and negative rotational torque fluctuations can be arbitrarily set, it is not necessary to change the engine each time, and the performance measuring work efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a first embodiment according to the present invention.

FIG. 2 is a schematic view showing a second embodiment according to the present invention.

FIG. 3 is a schematic diagram showing a conventional performance measuring device.

FIG. 4 is a schematic view showing the conventional performance measuring apparatus.

5 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

 21 ... Valve timing control mechanism 22 ... Timing sprocket (rotating body) 23 ... Drive shaft 26 ... Cylindrical gear (phase conversion means) 41 ... Inertial disk 42 ... Rotary actuator

Claims (1)

[Claims] 1. A rotary body driven by an engine, a camshaft having a cam for opening and closing an intake / exhaust valve by a rotational force transmitted from the rotary body, and an intermediary between the rotary body and the camshaft. In a performance measuring device of a valve timing control mechanism, which is equipped with a phase conversion means for converting a relative rotational phase of the both, the rotation of the rotating body is controlled, and the performance measuring device is provided at a position corresponding to the cam shaft. A performance measuring device for a valve timing control mechanism, characterized in that a rotary actuator for generating forward and reverse torsional vibrations is provided on the driven shaft.