JP2011220681A - Valve timing inspection apparatus for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately inspect a discrepancy with no influence by an outside error factor.SOLUTION: A valve timing inspection apparatus 1 comprises: an intake valve 33; an exhaust valve 43; a common port 40 collecting at least a plurality of exhaust ports; an intake air measurement unit 4 and an exhaust air measurement unit 5 for measuring an intake air volume or an exhaust air volume; a crank angle sensor 61 for detecting a rotation angle of a crankshaft 25; an outside motor 6 for externally driving a crankshaft 25 by rotation; and a controller 7 for determining an opening timing and a closing timing of respective valves 33 and 43, when the crankshaft 25 is driven by the outside motor 6, based on relation between the air flow volumes measured by the intake air measurement unit 4 and the exhaust air measurement unit 5 and the crank angle detected by the crank angle sensor 61. The controller 7 determines a discrepancy between an opening timing and a closing timing of the respective valves 33 and 43 based on measured air flow volume characteristics.

Description

  The present invention relates to an engine valve timing inspection apparatus having a common port in which a plurality of exhaust ports are assembled, and more particularly to an engine valve timing inspection for inspecting the opening / closing timing of an exhaust valve based on the flow rate of fluid flowing in the exhaust port by external driving. Relates to the device.

  The valve system of the engine includes a camshaft having a cam having a predetermined profile, and an intake valve and an exhaust valve that are opened and closed by the cam as the camshaft rotates. Inspecting intake / exhaust valve opening / closing operation is an important aspect of various engine inspections because malfunctions of intake / exhaust valve opening / closing operations affect engine performance and cause impact noise when the valve is closed. It is considered as an item.

  The valve timing inspection apparatus described in Patent Document 1 includes an external drive unit that is connected to a crankshaft and rotationally drives the crankshaft, a rotational phase detection unit that detects the rotational phase of the crankshaft, and a pressure in an engine cylinder. Pressure detecting means for detecting, one-way flow forming means for allowing outflow of air from the inside of the cylinder to the outside and preventing inflow of air from the outside to the inside of the cylinder, and pressure in the cylinder from the decreasing tendency to the increasing tendency Timing detecting means for detecting the changing rotational phase as the opening timing of the exhaust valve. In this valve timing inspection device, when the external drive means drives the crankshaft, the rotational phase in which the pressure in the cylinder changes from decreasing to increasing based on the pressure detection information in the cylinder and the rotation phase detection information of the crankshaft. Is detected as the opening timing of the exhaust valve, so that the opening timing of the valve can be detected even in a swing arm engine that is being assembled.

To increase engine output performance, an increasing number of vehicles are equipped with turbochargers that use engine exhaust to improve intake charging efficiency. In a turbocharger-equipped vehicle, in order to collect exhaust and rotate the intake turbine with a large exhaust pressure, a common port is formed by collecting multiple exhaust ports for each cylinder, and the exhaust from the common port of each cylinder is collected by the exhaust manifold. is doing.

JP 2003-254102 A

  In the valve timing inspection device of Patent Document 1, since the rotational phase in which the pressure in the cylinder changes from a decreasing tendency to an increasing tendency is detected, it is possible to include external error factors such as air leakage in the cylinder and compression torque due to the piston. There is a possibility that accurate valve timing based on actual valve behavior cannot be detected.

  In addition, in this valve timing inspection device, since the opening timing of the exhaust valve is detected based on the pressure in the cylinder, in the case of an engine having a common port in which a plurality of exhaust ports are assembled, it depends on the behavior of valves other than the valve to be inspected In order to remove the influence on the pressure in the cylinder, it is necessary to provide a mechanism for forcibly stopping the lifting / lowering operation of valves other than the valve to be inspected, which may complicate the inspection equipment.

It is an object of the present invention to detect an accurate valve timing shift without being affected by an external error factor in an engine having a common port in which a plurality of exhaust ports are gathered, and to simplify an inspection facility. It is to provide a timing inspection device.

The engine valve timing inspection apparatus according to claim 1 is a combustion chamber, a crankshaft, a plurality of intake ports and intake valves communicated with the combustion chamber, and a plurality of exhaust ports and exhaust valves communicated with the combustion chamber. And an engine valve timing inspection apparatus having a common port in which at least a plurality of exhaust ports are aggregated, a measuring means for measuring an intake flow rate or an exhaust flow rate, and a crank angle detection means for detecting a rotation angle of the crankshaft. An external driving means for rotationally driving the crankshaft from the outside, and a flow rate measured by the measuring means and a crank angle detected by the crank angle detecting means when the external driving means drives the crankshaft. Valve timing to determine the opening and closing timing of each valve based on the relationship And a constant section, the valve timing determination means is characterized in determining the deviation of the opening and closing timings of the valves on the basis of the measured flow characteristics.

The valve timing inspection device includes a measuring unit that measures the intake flow rate or the exhaust flow rate, and the valve timing determination unit is based on the relationship between the flow rate measured by the measuring unit and the crank angle detected by the crank angle detection unit. Since the opening / closing timing of each valve is determined, the intake / exhaust flow rate actually flowing through the intake / exhaust port can be detected based on the opening / closing timing of each valve.

According to a second aspect of the present invention, in the first aspect of the invention, the valve timing determining means determines a deviation of the opening / closing timing of each valve based on a flow rate change rate of the flow rate characteristic or a crank angle at which the flow rate is maximum. It is characterized by that.

According to a third aspect of the present invention, in the second aspect of the invention, the plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing, and the valve timing determining means When the flow rate change rate is equal to or greater than a predetermined value, it is determined that the opening / closing timing of any one of the plurality of exhaust valves is delayed.

According to a fourth aspect of the present invention, in the second aspect of the invention, the plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing, and the valve timing determining means When the flow rate change rate is less than or equal to a predetermined value, it is determined that the opening / closing timing of any one of the plurality of exhaust valves is advanced.

According to a fifth aspect of the present invention, in the second aspect of the invention, the plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing, and the valve timing determination means When the crank angle with the maximum flow rate is greater than or equal to a predetermined value, it is determined that the opening / closing timing of any one of the plurality of exhaust valves is delayed.

According to a sixth aspect of the present invention, in the second aspect of the invention, the plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing, and the valve timing determining means When the crank angle with the maximum flow rate is equal to or less than a predetermined value, it is determined that the opening / closing timing of any one of the plurality of exhaust valves is advanced.

According to the invention of claim 1, since the intake / exhaust flow rate actually flowing through the intake / exhaust port is measured based on the opening / closing timing of each valve, the actual intake / exhaust flow rate flowing through the intake / exhaust port can be detected. The influence of external error factors other than the above can be minimized, and accurate valve timing can be detected. Further, in order to determine the opening / closing timing deviation of each valve based on the measured flow characteristics, even an engine having a common port in which a plurality of exhaust ports are gathered is used for exhaust valves other than the exhaust valve to be inspected. The inspection equipment can be simplified without the need for inspection equipment or the like for stopping the lifting operation.

According to the second aspect of the present invention, it is possible to determine the deviation in the opening / closing timings of the plurality of exhaust valves based on the flow rate change rate of the flow rate characteristics or the crank angle at which the flow rate has the maximum value.
According to the invention of claim 3, it is possible to detect a delay in the opening timing of at least one of the plurality of exhaust valves from the flow rate change rate of the flow characteristics.
According to the invention of claim 4, the progress of the opening timing of at least one of the plurality of exhaust valves can be detected from the flow rate change rate of the flow characteristics.

According to the invention of claim 5, it is possible to detect a delay in the opening timing of at least one of the plurality of exhaust valves from the crank angle at which the flow rate is maximum.
According to the invention of claim 6, it is possible to detect the progress of the opening timing of at least one of the plurality of exhaust valves from the crank angle at which the flow rate is maximum.

1 is a schematic view of an engine valve timing inspection apparatus according to Embodiment 1 of the present invention. It is a principal part enlarged view of an engine. It is the III-III sectional view taken on the line of FIG. It is a figure which shows a valve timing control mechanism. It is the VV sectional view taken on the line of FIG. FIG. 6 is a view corresponding to FIG. 5 when the valve timing is changed to the most advanced angle side. FIG. 6 is a view corresponding to FIG. 5 when the valve timing is changed to the most retarded angle side. It is explanatory drawing of the valve timing determination method. It is a step figure showing a processing procedure of valve timing inspection. It is a time chart of a valve timing inspection. It is a figure which shows the correlation with the valve lift amount of each valve | bulb detected by the measurement process, the crank angle, and the fluid flow rate. It is explanatory drawing of the shift | offset | difference determination of the opening / closing timing of an exhaust valve.

  Hereinafter, modes for carrying out the present invention will be described based on examples. In addition, the left-right direction in a figure is demonstrated as a left-right direction.

Hereinafter, Example 1 of the present invention will be described with reference to FIGS.
As shown in FIG. 1, in the valve timing inspection apparatus 1, the engine E in the previous stage (in the middle of assembly) where the intake manifold and exhaust manifold are assembled is the inspection target. The engine E is transported to an inspection station of the valve timing inspection device 1 by a transport device such as a conveyor (not shown) while being mounted on a pallet (not shown).

The configuration of the valve timing inspection apparatus 1 will be described.
As shown in FIG. 1, the valve timing inspection apparatus 1 includes an input device 2, an output device 3, an intake side measurement unit 4 (measurement unit), an exhaust side measurement unit 5 (measurement unit), and a crankshaft 25. An external motor 6 (external drive means) that rotationally drives, a control unit 7 (valve timing determination means), a crank angle sensor 61, an intake cam angle sensor 62, an exhaust cam angle sensor 63, and the like are provided. The input device 2 includes a keyboard and a mouse, and is configured to be able to input various information. The output device 3 includes a display device such as a display and a CRT, a printing device such as a printer, and the like, and is configured to output various information. The external motor 6 is an electric motor that forcibly rotates the crankshaft 25. The crank angle sensor 61, the intake cam angle sensor 62, and the exhaust cam angle sensor 63 are encoders that can detect the rotational phase of each shaft, and each pulse is rotated at a predetermined unit angle. It is configured to output a pulse.

Since the intake side measurement unit 4 and the exhaust side measurement unit 5 are configured by the same known differential pressure type flow rate sensor, the intake side measurement unit 4 will be described, and the description of the exhaust side measurement unit 5 will be omitted.
The intake side measurement unit 4 includes a cylindrical laminar flow portion 4a through which a fluid can flow and a differential pressure portion 4b that can detect a pressure drop of the fluid flowing through the laminar flow portion 4a.
The intake side measuring unit 4 detects the flow rate by utilizing the fact that when the fluid flows in the laminar flow part 4a in a laminar flow, the pressure loss and the flow rate in the laminar flow region have a proportional relationship (Hangen-Poiseuille's law). ing.
The differential pressure part 4b measures the pressure at the first position upstream of the laminar flow part 4a and the pressure at the second position separated from the first position in the downstream direction by a predetermined distance, and the difference between the first position and the second position. Detect pressure. The flow rate of the fluid introduced into the laminar flow part 4a can be calculated by the following equation (1) based on the detected differential pressure.
Q = K × ΔP (1)
Here, Q is the volume flow rate of the fluid, K is the flow coefficient, and ΔP is the differential pressure.

  The control unit 7 includes a ROM, a RAM, and a CPU, and stores a control program for controlling the valve timing inspection device 1 and data necessary for controlling the valve timing inspection device 1. When the external motor 6 drives the crankshaft 25, the control unit 7 is based on the relationship between the flow rate measured by the intake side measurement unit 4 and the exhaust side measurement unit 5 and the crank angle detected by the crank angle sensor 61. The opening / closing timing of the intake valve 33 and the exhaust valve 43 is determined. The control unit 7 receives detection signals from the crank angle sensor 61, the intake cam angle sensor 62, and the exhaust cam angle sensor 63. The crank angle sensor 61 detects the rotation speed and crank angle of the crankshaft 25, and the intake cam angle sensor 62 and the exhaust cam angle sensor 63 detect the rotation speeds of the intake camshaft 38 and the exhaust camshaft 48 and the intake camshaft 38. The rotational phase of the exhaust camshaft 48 is detected.

  Based on FIGS. 1 and 8, a method for determining the opening / closing timing of the intake valve 33 and the exhaust valve 43 will be described in detail. In the present embodiment, the crankshaft 25 is rotationally driven by the external motor 6, and the flow rate of the fluid flowing through the ports 31, 32, 40 is detected by the lifting and lowering operation of the piston 26. As shown in FIG. 8, when the crank angle is 0 deg, 360 deg, and 720 deg are TDC (top dead center) and the crank angle is 180 deg and 540 deg are BDC (bottom dead center), the crankshaft 25 of the external motor 6 With the rotation, the piston 26 moves up and down between TDC and BDC. In the figure, “EX” indicates a state in which the exhaust valve 43 is open, “IN” indicates a state in which the intake valve 33 is open, and the flow rate discharged from the combustion chamber 27 is added, The flow rate introduced into the combustion chamber 27 is indicated by minus.

When the piston 26 is in an expansion operation (0 to 180 deg), the intake valve 33 is in a closed state, and the exhaust valve 43 increases the valve lift and starts an opening operation. There is no flow rate of fluid flowing through the exhaust common port 40 before the exhaust valve 43 is opened, and fluid is introduced into the combustion chamber 27 by the piston 26 after the exhaust valve 43 is opened. Thus, the opening timing of the exhaust valve 43 is detected by detecting the introduction start timing of the exhaust side intake air. When the piston 26 is in a compression operation (180 to 360 deg), the intake valve 33 is in a closed state, and the exhaust valve 43 starts the closing operation by reducing the valve lift amount. Before the exhaust valve 43 is closed, fluid is discharged from the combustion chamber 27 to the exhaust common port 40 by the piston 26. After the exhaust valve 43 is closed, the flow rate of the fluid flowing through the exhaust common port 40 is not detected. Thereby, the closing timing of the exhaust valve 43 is detected by detecting the exhaust end timing of the exhaust side exhaust.

When the piston 26 is in expansion operation (360 to 540 deg), the exhaust valve 43 is in a closed state, and the intake valve 33 increases the valve lift amount and starts to open. There is no flow rate of fluid flowing through the intake ports 31 and 32 before the intake valve 33 is opened, and fluid is introduced into the combustion chamber 27 by the piston 26 after the intake valve 33 is opened. Thus, the opening timing of the intake valve 33 is detected by detecting the introduction start timing of the intake side intake air. When the piston 26 is in a compression operation (540 to 720 deg), the exhaust valve 43 is in a closed state, and the intake valve 33 starts the closing operation by reducing the valve lift amount. Before the intake valve 33 is closed, fluid is discharged from the combustion chamber 27 to the intake ports 31 and 32 by the piston 26. After the intake valve 33 is closed, the flow rate of fluid flowing through the intake ports 31 and 32 is not detected. Accordingly, the closing timing of the intake valve 33 is detected by detecting the exhaust end timing of the intake side exhaust.

Next, the engine E to be inspected will be described with reference to FIGS.
The engine E includes a cylinder block 21, a cylinder head 22 disposed on the cylinder block 21 via a gasket (not shown), and a pair of cam housings 23a and 23b disposed on the cylinder head 22. And so on. A cylinder 24 is formed in the cylinder block 21, and a piston 26 that can move up and down in accordance with the rotation of the crankshaft 25 is slidably fitted into the cylinder 24. A partially conical inclined wall surface is formed on the lower surface of the cylinder head 22, and the inclined wall surface forms a combustion chamber 27 in cooperation with the top surface of the piston 26 and the inner peripheral surface of the cylinder 24. A plug hole 28 for mounting a spark plug (not shown) is formed in the central portion of the inclined wall surface.

  On the right side of the cylinder bore of the cylinder head 22, two independent intake ports 31 and 32 that guide intake air to the cylinder 24 are provided. These intake ports 31 and 32 are formed such that one end opens to the right inclined wall surface of the combustion chamber 27 via an intake side valve seat (not shown) and the other end opens to the right wall of the cylinder head 22. ing. The intake ports 31 and 32 are provided side by side in the cylinder arrangement direction.

On the left side of the cylinder bore of the cylinder head 22, two independent exhaust ports 41 and 42 that guide exhaust gas outward from the cylinder 24 are provided. These exhaust ports 41, 42 are formed such that one end opens on the left inclined wall surface of the combustion chamber 27 via an exhaust side valve seat (not shown), and the other end opens on the left wall of the cylinder head 22. ing. The exhaust ports 41 and 42 are provided side by side in the cylinder arrangement direction, and are gathered into one exhaust common port 40 on the cylinder head left side wall side.

  The cylinder head 22 is provided with two intake valves 33 that open and close the intake side valve seats corresponding to the intake ports 31 and 32, respectively. These intake valves 33 are slidably fitted into the cylinder head 22 so as to be slidable, and are provided so as to be movable up and down. It is biased in the (valve closing direction). The upper ends of the intake valves 33 are provided in the middle of the intake camshaft 38 by the rotation of the intake camshaft 38 via a pair of swing arms 37 supported at one end by respective hydraulic lash adjusters 36. The two intake valves 33 are configured to open and close at the same predetermined timing by being driven downward (in the valve opening direction) against the urging force of the valve spring 35 in accordance with the profiles of the two intake cams 38a. . Since the two intake cams 38a have the same structure, the two intake valves 33 operate at the same valve timing.

  The cylinder head 22 is provided with two exhaust valves 43 corresponding to the exhaust ports 41 and 42, each of which opens and closes the exhaust side valve seat. These exhaust valves 43 are slidably inserted into the cylinder head 22 so as to be slidable, and are provided so as to move up and down. The exhaust valves 43 are moved upward by a biasing force of a valve spring 45 via a spring seat 44 at each valve shaft end. It is biased in the (valve closing direction). The upper ends of the exhaust valves 43 are provided in the middle of the exhaust camshaft 48 by the rotation of the exhaust camshaft 48 through a pair of swing arms 47 supported at one end by the respective hydraulic lash adjusters 46. The two exhaust valves 43 are configured to open and close at the same predetermined timing by being driven downward (in the valve opening direction) against the urging force of the valve spring 45 in accordance with the profile of the exhaust cam 48a. Since the two exhaust cams 48a have the same structure, the two exhaust valves 43 operate at the same valve timing.

Next, the valve timing control mechanism 50 will be described with reference to FIGS.
The valve timing control mechanism 50 is provided at one end of the intake camshaft 38, and includes a case 51, a vane 52, an electric motor 53, and the like. A similar valve timing control mechanism 50 can be provided at one end of the exhaust camshaft 48 to change the valve timing of the exhaust valve 43.

The case 51 is integrally configured from an annular sprocket portion 54 provided on the outer periphery of the case 51, and a cylindrical case body 55 that can accommodate a vane 52, a power transmission mechanism (not shown), and the like. Teeth (not shown) that can be engaged with the timing chain 29 are formed on the outer peripheral surface of the sprocket portion 54, and the sprocket portion 54 and the crankshaft 25 are connected by the timing chain 29. The timing chain 29 is mounted so as to span the sprocket portion (not shown) of the crankshaft 25, the sprocket portion (not shown) of the exhaust camshaft 48, and the sprocket portion 54. The driving force of the engine E is transmitted from the crankshaft 25 to the sprocket portion 54 via the timing chain 29, and the case 51 rotates by this driving force.

A through hole is formed in the central portion of the case main body 55, and the intake camshaft 38 is rotatably inserted in the through hole. Protruding portions 56 a and 56 b that protrude in the axial direction of the intake camshaft 38 are provided on the inner periphery of the case body 55. The projecting portion 56a is provided on the further advance side than the most advanced traveling position used for traveling control with respect to the intake camshaft 38, and the projecting portion 56b is the most travelable portion used for traveling control with respect to the intake camshaft 38. Since it is provided further on the retard side than the retard position, the rigidity of the case body 55 can be increased without hindering the change of the valve timing for travel control. It is possible to arrange two or more protrusions at equal intervals.

  The vane 52 is formed to be rotatable relative to the case 51, and is configured to be able to change a valve timing at which the intake valve 33 opens and closes. The vane 52 is fastened and fixed to one end portion of the intake camshaft 38 with a bolt or the like, and forms an extended portion extending in one direction of the intake camshaft 38. On the outer peripheral side of the vane 52, a protrusion 57 protruding in the radial direction is provided. Therefore, the protrusion 57 is regarded as being integral with the intake camshaft 38, and the protrusion 57 performs the same rotation operation as the intake camshaft 38.

The electric motor 53 includes an armature, a rotor, and the like, and includes a vane 52 and a side end portion of a case main body 55 that houses a power transmission mechanism (not shown) that transmits rotational power from the electric motor 53 to the vane 52. It is arranged to block. The power transmission mechanism holds the sun gear of the external gear, the ring gear of the internal gear arranged concentrically with the sun gear, and the pinion gear meshing with the sun gear and the ring gear so as to rotate and revolve. This is a known gear mechanism having a carrier as a rotating element. The electric motor 53 is controlled by a PCM (Powertrain Control Module) 30 (see FIG. 1). The current and voltage of the electric motor 53 are detected by an ammeter or a voltmeter and input to the PCM 30.

As shown in FIG. 5, when the valve timing control mechanism 50 is not operated, the electric motor 53 does not rotate, so that the protrusion 57 is held at a substantially intermediate position between the protrusions 56a and 56b, as indicated by arrows. The intermediate position is maintained and the counterclockwise rotation is performed similarly to the rotation of the timing chain 29. Therefore, the intake camshaft 38 does not rotate relative to the case body 55, and the intake valve 33 opens and closes at the most retarded angle or at any valve timing (position indefinite) between the advance angle and the retard angle. To do.

As shown in FIG. 6, when the valve timing control mechanism 50 is operated to the advance side, the electric motor 53 rotates the vane 52 counterclockwise, so the intake camshaft 38 rotates counterclockwise relative to the case body 55. As shown by the arrow, the advance side position is maintained, and the advance side position is maintained and the counterclockwise rotation is performed in the same manner as the timing chain 29 is rotated.

As shown in FIG. 7, when the valve timing control mechanism 50 is operated to the retard side, the electric motor 53 rotates the vane 52 to the right, so the intake camshaft 38 rotates to the right relative to the case body 55. As shown by the arrows, the retarded side position is maintained and the counterclockwise rotation is performed in the same manner as the timing chain 29.

In the present embodiment, the projecting portion 56a is formed at a further advance side position (the most advanced angle position for inspection) than the most advanced angle position for traveling used in actual vehicle traveling, and the most retarded angle for traveling used in actual vehicle traveling. The protrusion 56b is formed at a position more retarded than the position (the most retarded position for inspection), and the protrusion 56a or the protrusion 56b and the protrusion 57 are brought into contact with each other for inspection. The most advanced angle position for inspection and the most retarded position for inspection are not used in normal traveling control, but when learning the most advanced angle position for traveling, the valve timing control mechanism 50 is set to the most advanced angle position for inspection. Or it may be operated to the most retarded position for inspection.

Next, a processing procedure for valve timing inspection will be described with reference to FIGS. 1 and 9 to 12.
In the preparation step S1, the engine E is transported to the inspection position, and the drive shaft of the external motor 6 and the crankshaft 25 are coupled so as to be capable of synchronous rotation. The laminar flow portions 4 a of the two intake side measurement units 4 are mounted on the engine E so as to communicate with the intake ports 31 and 32 that open on the right side wall of the cylinder head 22. Thus, the fluid flow rate flowing through the intake ports 31 and 32 corresponds to the fluid flow rate flowing through the laminar flow portion 4a. The laminar flow part 5 a of the exhaust side measuring part 5 is mounted on the engine E so as to communicate with the exhaust common port 40 opened in the left side wall of the cylinder head 22. Thereby, the flow rate of the fluid flowing through the exhaust common port 40 corresponds to the flow rate of the fluid flowing through the laminar flow portion 5a.

In the cranking step S <b> 2, the control unit 7 outputs a cranking start signal to the external motor 6. The external motor 6 starts rotating the crankshaft 25 and increases the rotational speed to a predetermined target rotational speed, for example, 200 rpm, and then maintains this rotational speed.

In the most retarded angle control step S3, when the rotational speed of the external motor 6 increases to the target rotational speed (after 1 second of cranking start), the control unit 7 outputs the most retarded angle control signal to the PCM 30. The PCM 30 controls the electric motor 53 of the valve timing control mechanism 50 to fix the intake valve 33 to the most retarded angle side. The electric motor 53 is controlled with a predetermined duty to rotate the vane 52 rightward to the most retarded position for inspection which is further retarded than the most retarded position for traveling used in actual vehicle travel, and this most retarded angle for inspection. The position is controlled with a predetermined duty in order to keep the position fixed. As a result, the protrusion 57 of the vane 52 abuts against the protrusion 56 b of the case body 55, and this abutment state is maintained while the external motor 6 rotationally drives the crankshaft 25. As a result, the amount of electric power of the electric motor 53 required for the most retarded angle control and the amount of power that holds the intake valve 33 at the most retarded position for inspection can be suppressed. Further, since the protrusion 57 of the vane 52 is in contact with the protrusion 56 b of the case main body 55, the pulsation of the intake valve 33 due to the cogging torque of the electric motor 53 can be suppressed.

In the measurement step S4, when the protrusion 57 comes into contact with the protrusion 56b, for example, after 2 seconds from the start of cranking, the control unit 7 outputs a measurement start signal to the intake side measurement unit 4 and the exhaust side measurement unit 5. The time required for the protrusion 57 to contact the protrusion 56b is obtained in advance by experiments.
In the measurement step S4, the flow rate of the fluid flowing through the intake ports 31, 32 and the exhaust common port 40 is detected by the intake side measurement unit 4 and the exhaust side measurement unit 5. The fluid flow rates of the exhaust side intake, the exhaust side exhaust, the intake side intake, and the intake side exhaust detected by the intake side measurement unit 4 and the exhaust side measurement unit 5 are output to the control unit 7.

In the valve timing determination step S5, the control unit 7 correlates the crank angle and the fluid flow rate (flow rate characteristics) for each flow rate of the exhaust side intake, exhaust side exhaust, intake side intake, and intake side exhaust detected in the measurement step. ) Is detected (see FIG. 11), and the exhaust-side intake start timing, the exhaust-side exhaust end timing, the intake-side intake start timing, and the intake-side exhaust end timing are respectively detected. As a result, the opening / closing timing of the intake valve 33 and the opening / closing timing of the exhaust valve 43 are detected and compared with a preset target opening / closing timing.

As shown in FIG. 11, since the valve lift characteristic of the intake valve 33 and the valve lift characteristic of the exhaust valve 43 partially overlap each other, the flow rate of the fluid flowing through the exhaust common port 40 is temporarily taken into the intake (minus) state in the exhaust side exhaust. The phenomenon which shifts to the side occurs. Therefore, the closing timing of the exhaust valve 43 is determined in consideration of the intake / exhaust valves 33 and 43 valve lift characteristics.

  Further, in the valve timing determination step S5, the deviation of the opening / closing timing of the exhaust valve 43 is determined based on the flow rate characteristics of the exhaust side intake or the exhaust side exhaust. In the valve timing determination step S5, the flow rate change rate is detected from the detected flow rate characteristic of the exhaust side intake air.

The opening / closing timing deviation determination processing of the exhaust valve 43 based on the flow rate characteristics of the exhaust side intake will be described.
As shown in FIG. 12, when the opening / closing timings of the exhaust valve 43 of the exhaust port 41 and the exhaust valve 43 of the exhaust port 42 are the same, the flow rate characteristic of the fluid flow rate flowing through the exhaust common port 40 shows the exhaust side intake characteristic L1. The flow rate change rate of the exhaust-side intake characteristic L1, which is a determination criterion, is obtained in advance through experiments or the like as the reference flow rate change rate.

When the detected flow characteristic of the exhaust side intake gas is the exhaust side intake characteristic L2, when the flow rate change rate of the so-called exhaust side intake characteristic L2 is equal to or higher than the reference flow rate change rate, the opening timing of one of the exhaust valves 43 is delayed. It is determined that When the detected flow characteristic of the exhaust-side intake is the exhaust-side intake characteristic L3, and when the flow rate change rate of the so-called exhaust-side intake characteristic L3 is equal to or less than the reference flow rate change rate, the opening timing of one of the exhaust valves 43 advances. It is determined that Similarly, it is possible to determine the deviation of the closing timing of the exhaust valve 43 based on the flow rate characteristic of the exhaust side exhaust.

Further, instead of the determination based on the flow rate change rate, the deviation of the opening / closing timing of the exhaust valve 43 may be determined by detecting the crank angle at which the flow rate of the detected flow rate characteristic shows the maximum value (peak value). In this case, the crank angle at which the flow rate of the exhaust-side intake characteristic L1 serving as a criterion is the maximum value is obtained in advance through experiments or the like as the reference crank angle C1.

When the detected flow characteristic of the exhaust-side intake is the exhaust-side intake characteristic L2, when the crank angle C2 at which the flow rate of the so-called exhaust-side intake characteristic L2 shows the maximum value is equal to or greater than the crank angle C1, either one of the exhaust valves 43 It is determined that the opening timing is delayed. When the detected flow characteristic of the exhaust-side intake is the exhaust-side intake characteristic L3, when the crank angle C3 at which the flow rate of the so-called exhaust-side intake characteristic L3 shows the maximum value is equal to or less than the crank angle C1, either one of the exhaust valves 43 It is determined that the opening timing is advanced. Similarly, it is possible to determine the deviation of the closing timing of the exhaust valve 43 based on the flow rate characteristic of the exhaust side exhaust.

After the end of the valve timing determination step S5, the control unit 7 outputs a measurement end signal and a cranking end signal. The measurement by the intake side measurement unit 4 and the exhaust side measurement unit 5 is terminated by the measurement end signal, and the rotational drive of the external motor 6 is terminated by the cranking end signal. Further, the duty control for the electric motor 53 is canceled by the cranking end signal.
For the other cylinders 24, the above-described valve timing inspection is performed.

Next, the operation and effect of the valve timing inspection apparatus 1 will be described.
The valve timing inspection apparatus 1 includes a combustion chamber 27, a crankshaft 25, a plurality of intake ports 31 and 32 and an intake valve 33 communicated with the combustion chamber 27, and a plurality of exhaust ports 41 communicated with the combustion chamber 27. , 42 and the exhaust valve 43, and the valve timing inspection apparatus 1 for the engine E having at least a plurality of exhaust ports 41, 42, and an intake side measuring unit 4 for measuring the intake flow rate or the exhaust flow rate. The exhaust side measurement unit 5, the crank angle sensor 61 that detects the rotation angle of the crankshaft 25, the external motor 6 that rotationally drives the crankshaft 25 from the outside, and when the external motor 6 drives the crankshaft 25, the intake side The flow rate measured by the measurement unit 4 and the exhaust side measurement unit 5 and the clan detected by the crank angle sensor 61 And a control unit 7 for determining the opening / closing timing of the valves 33 and 43 based on the relationship with the angle. The control unit 7 determines a deviation in the opening / closing timing of the valves 33 and 43 based on the measured flow rate characteristics. ing.

  According to this valve timing inspection apparatus 1, the intake / exhaust ports 31, 32, 41, 42 are connected to detect the intake / exhaust flow rates actually flowing through the intake / exhaust ports 31, 32, 41, 42 based on the opening / closing timing of each valve. The actual intake / exhaust flow rate flowing can be detected, the influence of external error factors other than the behavior of the valves 33 and 43 can be minimized, and the accurate valve timing can be detected. Further, in order to determine a deviation in the opening / closing timing of the valves 33 and 43 based on the measured flow characteristics, even the engine E including the common port 40 in which the plurality of exhaust ports 41 and 42 are assembled is to be inspected. The inspection equipment can be simplified without requiring inspection equipment such as stopping the lifting operation of the exhaust valves 43 other than the exhaust valve 43.

The control unit 7 can determine the deviation of the opening / closing timing of each exhaust valve 43 based on the detected flow rate change rate of the flow rate characteristic or the crank angle at which the flow rate has the maximum value.
The plurality of intake valves 33 are set at the same opening / closing timing and the plurality of exhaust valves 43 are set at the same opening / closing timing. When the flow rate change rate of the flow characteristics is equal to or higher than the reference flow rate change rate, the control unit 7 43, the opening / closing timing of any one of the plurality of exhaust valves 43 can be detected based on the flow rate change rate of the flow characteristics. it can.

The plurality of intake valves 33 are set to the same opening / closing timing, the plurality of exhaust valves 43 are set to the same opening / closing timing, and the control unit 7 determines that the plurality of exhaust valves is set when the flow rate change rate of the flow characteristics is equal to or less than the reference flow rate change rate. 43, the opening / closing timing of any one of the plurality of exhaust valves 43 can be detected based on the flow rate change rate of the flow characteristics. it can.

The plurality of intake valves 33 are set at the same opening / closing timing, the plurality of exhaust valves 43 are set at the same opening / closing timing, and the control unit 7 is configured to perform a plurality of operations when the crank angle at which the flow rate of the flow characteristic is the maximum value is greater than or equal to the reference crank angle. In order to determine that the opening / closing timing of one of the exhaust valves 43 is delayed, the opening timing of at least one of the plurality of exhaust valves 43 is delayed due to the crank angle at which the flow rate is maximum. Can be detected.

The plurality of intake valves 33 are set at the same opening / closing timing, the plurality of exhaust valves 43 are set at the same opening / closing timing, and the control unit 7 is configured to perform a plurality of operations when the crank angle at which the flow rate of the flow characteristic is the maximum value is equal to or less than the reference crank angle. In order to determine that the opening / closing timing of any one of the exhaust valves 43 is advanced, the opening timing of at least one of the plurality of exhaust valves 43 is advanced according to the crank angle at which the flow rate is maximum. Can be detected.

Next, a modification in which the above embodiment is partially changed will be described.
1) In the above-described embodiment, an example in which a differential pressure type flow sensor is used as a measuring unit has been described. However, any sensor that can measure at least an intake flow rate or an exhaust flow rate flowing in each port may be used. Applicable.

2) In the above-described embodiment, the example in which the opening / closing timing of the exhaust valve is determined based on the change rate of the flow rate characteristic of the exhaust port or the crank angle at which the flow rate of the flow characteristic is the maximum value has been described. It is also possible to determine the opening / closing timing of the intake valve based on the crank angle at which the flow rate of the change rate or flow rate characteristic is the maximum value.

3) In the above embodiment, the example in which the electric valve timing control mechanism is provided only on the intake valve side has been described, but it is also possible to provide the electric valve timing control mechanism on both the intake valve side and the exhaust valve side. is there. An electric valve timing control mechanism may be provided only on the exhaust valve side.

4) In the above embodiment, the example of determining the opening / closing timing of both the intake valve and the exhaust valve has been described. However, it is also possible to detect the flow characteristic of only the exhaust valve and determine the opening / closing timing of only the exhaust valve. is there. When inspecting only the opening / closing timing of the exhaust valve, the intake port opening is closed and the flow rate of the fluid flowing through the exhaust port is measured.

5) In addition, those skilled in the art can implement the present invention in various forms with various modifications without departing from the spirit of the present invention, and the present invention includes such modifications. is there.

  The present invention provides a valve timing inspection device for an engine having a common port in which a plurality of exhaust ports are assembled. By checking the opening / closing timing of the exhaust valve based on the flow characteristics flowing through the common port by external driving, an external error factor is obtained. Therefore, it is possible to detect an accurate valve timing shift without being affected by the above, and to simplify the inspection equipment.

E Engine 1 Valve timing inspection device 4 Intake side measurement unit 5 Exhaust side measurement unit 6 External motor 7 Control unit 25 Crankshaft 26 Piston 27 Combustion chambers 31, 32 Intake port 33 Intake valve 38 Intake camshaft 40 Exhaust common port 41, 42 Exhaust port 43 Exhaust valve 61 Crank angle sensor

Claims (6)

A combustion chamber, a crankshaft, a plurality of intake ports and intake valves that communicate with the combustion chamber, a plurality of exhaust ports and exhaust valves that communicate with the combustion chamber, and a common port that includes at least a plurality of exhaust ports In an engine valve timing inspection device equipped with
A measuring means for measuring the intake flow rate or the exhaust flow rate;
Crank angle detection means for detecting the rotation angle of the crankshaft;
External drive means for rotationally driving the crankshaft from the outside;
Valve timing determination for determining the opening / closing timing of each valve based on the relationship between the flow rate measured by the measuring means and the crank angle detected by the crank angle detecting means when the external driving means drives the crankshaft. Means and
The valve timing judging device according to claim 1, wherein the valve timing judging means judges a deviation of the opening / closing timing of each valve based on the measured flow rate characteristic.   2. The engine valve according to claim 1, wherein the valve timing determination unit determines a difference in opening / closing timing of each valve based on a flow rate change rate of the flow rate characteristic or a crank angle at which the flow rate has a maximum value. Timing inspection device. The plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing,
The valve timing determination means determines that the opening / closing timing of any one of the plurality of exhaust valves is delayed when the flow rate change rate of the flow rate characteristic is equal to or greater than a predetermined value. The valve timing inspection device for an engine according to 1. The plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing,
The valve timing determination means determines that the opening / closing timing of any one of the plurality of exhaust valves is advanced when a flow rate change rate of the flow rate characteristic is a predetermined value or less. The valve timing inspection device for an engine according to 1. The plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing,
The valve timing determining means determines that the opening / closing timing of any one of the plurality of exhaust valves is delayed when the crank angle at which the flow rate of the flow rate characteristic has a maximum value is a predetermined value or more. The valve timing inspection device for an engine according to claim 2. The plurality of intake valves are set at the same opening / closing timing and the plurality of exhaust valves are set at the same opening / closing timing,
The valve timing determination means determines that the opening / closing timing of any one of the plurality of exhaust valves is advanced when the crank angle at which the flow rate of the flow rate characteristic has a maximum value is equal to or less than a predetermined value. The valve timing inspection device for an engine according to claim 2.