JPS59119007A - Suction air flow rate control device of internal- combustion engine - Google Patents

Abstract

PURPOSE:To enable to perform the output control of an engine without using throttle valve by a method wherein a timing control device, which is arranged between an camshaft for driving suction valves only and the power transmission device of a crankshaft, is operated with an accelerator pedal. CONSTITUTION:Slits 62 and 64, which intersect each other, are respectively provided on an inner sleeve 54 coupled to a camshaft 34 for driving suction valves only and on the outer sleeve 60 of a timing pulley 42, which transmits a driving force from a crankshaft side. Roller bearings 66 and 68, which are inserted in both the slits 62 and 64, are axially shifted in order to control suction valve timing. Since the shifting of the roller bearings 66 and 68 is so constituted as to be controlled with an accelerator pedal 84, the output control of an engine is performed without using throttle valve.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal combustion engine that does not have a throttle valve and controls the amount of intake air by changing the pulp timing.

Conventionally, the intake air amount of an internal combustion engine is controlled by a throttle valve, but in this case, when the throttle valve is not fully opened at partial load, pumping loss occurs, causing deterioration of fuel efficiency.

Therefore, various internal combustion engines have already been proposed in which the amount of intake air is controlled by controlling the pulp timing according to the load without providing a throttle valve. Utility patent application filed in 1983-1986 by this applicant as an internal combustion engine of this kind
In No. 395, the timing of the intake valve was advanced or retarded by twisting the intake valve camshaft, thereby controlling the amount of intake air.

It is an object of the present invention to provide such a twist-type device for the intake valve camshaft, which can operate reliably to control pulp timing despite its simple structure. In order to achieve this objective, the variable pulp timing mechanism of the present invention is composed of an inner sleeve on the camshaft side and an outer sleeve on the timing pulley side, and the inner sleeve and outer sleeve are mutually inclined. A roller bearing that fits into both of the slits is provided on a bearing support that is connected to an accelerator pedal and reciprocates in parallel with the camshaft direction.

The following will be explained with reference to the drawings. In FIG. 1, a piston 12 is provided in a cylinder block IO so as to be able to rise freely. The piston 12 is connected to a crankshaft 16 via a connecting rod 14. A cylinder head 18 is placed on the four cylinder tabs lO. cylinder head 1
An intake boat 20 and an exhaust port 22 are formed in the 8,
They are connected to a combustion chamber 30 via an intake valve 24 and an exhaust valve 26, respectively. The intake boat 20 has an exhaust port 2 in the intake pipe 31.
2 is connected to the exhaust pipe 32 as usual, but the intake pipe 31
Unlike usual, there is no throttle valve installed inside.

There is a cover 33 on the cylinder head 18. This engine is a DOHC type engine in which an intake valve and an exhaust valve are driven by separate camshafts, and includes an intake camshaft 34 and an exhaust camshaft 36 inside a cover 33. The cam 34' of the intake camshaft 34 acts on the intake pulp stem against the spring 38 to open the intake valve 24. Further, the cam 36' on the exhaust camshaft 36 acts on the exhaust valve nutem against the spring 40 to open and close the exhaust valve 26. Timing pulleys 42 and 44 are mounted on the intake camshaft 34 and the exhaust camshaft 36, respectively, and are connected to a timing pulley 48 on the crankshaft 16 via a timing belt 46.

The intake camshaft 34 is provided with a variable pulp timing device, indicated generally at 52. This variable pulp timing device 52 is constructed as shown in FIG. That is, the inner sleeve 54 is attached to one end of the intake camshaft 34 with a bolt 56.
Fixed by

The timing pulley 42 is connected to this inner sleeve 54.
mounted on top by bearings 58. An outer sleeve 60 and an inner sleeve 54 extend integrally from the hub of the timing pulley 42 . The inner sleeve and the outer sleeve have slits 62 and 64 close to each other. As shown in FIG. 3, one slit 62 is straight, while the other slit 64 is inclined, and the two slits intersect. Roller bearings 66 and 68- are located within the slits 62 and 64, respectively. The roller bearings 66 and 68 are mounted on the radial shaft 70' of a tubular bearing support 700. The cylindrical bearing support 70 moves inward of the inner sleeve 54 in a direction parallel to the camshaft.One end of the operating rod 78, which reciprocates left and right while being sealed by a case 74 and a seal 76, is supported by a bearing 80. It is connected to a support body 70. The other end of the front door 8 is connected to an accelerator pedal 84 by a link 82.
K-linked.

Detailing the operation of the present invention, the rotation of the crankshaft 16 is transmitted to the camshafts 34 and 36 via the timing pulley 48, the timing belt 46, and the timing pulleys 42 and 44. The exhaust camshaft 36 is directly rotated by a pulley 44, while for the intake camshaft 34, the timing pulley 42, ie the outer sleeve 60, is rotated by the slit 6.
4 and the shaft portion 70' through the bearing 68, and the shaft portion 70' rotates the inner sleeve 54, that is, the intake camshaft 34 through the bearing 66 and the slit 62. As a result, the valve is opened and closed at the crank angle at which the cam 34' or the pass 36' engages with the intake valve 24 or the exhaust valve 26.
Regarding 6, I of 7 (the lube timing is constant, but the intake valve 24 is variable) (the lube timing mechanism changes depending on how much the accelerator pedal 84 is depressed. In other words, the roller bearings 66 and 68 are aligned with the arrow A1 or the person, This is because a linear movement in the direction n or B2 causes rotational movement between the inner sleeve and the outer sleeve.

When the accelerator pedal 84 is under a light load with little depression, the operating rod 78 is located on the right side in FIG. In Fig. 3, B□ is rotated relative to the direction of force and becomes K. In this case, the pulp timing of the intake valve 24 is on the delayed side, which is schematically represented in FIG. Finish opening. That is, the piston 12 begins the suction stroke and the intake valve opens at an angle α, so that suction air %-#,-"lk1% is introduced into the combustion chamber 30 via the boat 20, but reaches the bottom dead center and begins the compression stroke. Even when moving to , β performs more than half of that stroke.

Since the intake valve 24 is open to an angle of
The air introduced into the intake bow) is pushed back to the 20 side.
As a result, the amount of intake air becomes small commensurate with the partial load.

When the accelerator pedal 84 is pressed under high load, the rod 78 is located on the left side in FIG. 2 (in the direction of arrow A2), which means that the inner sleeve 5
Rotate 4 in direction B.

The pulp timing of the intake valve in this case is schematically shown in FIG. 4(B) on the advance side. That is, it begins to open at an angle α before top dead center and β after bottom dead center.

It opens at an angle of . Since the intake valve 24 closes immediately after bottom dead center, less air is returned to the intake boat, and a large amount of air commensurate with high-load operation contributes to combustion.

As described above, in the present invention, the amount of intake air can be controlled by connecting the variable pulp timing mechanism to the accelerator pedal without providing a throttle valve, and as a result, there is no throttling loss and the fuel efficiency during partial load operation is reduced. It gets expensive. In addition, since the mechanism of the present invention switches the pulp timing by moving the roller bearings in the intersecting slits, backlash-free operation can be achieved with only a slight operating force, and reliable intake air volume control can be achieved. .

[Brief explanation of drawings]

FIG. 1 is a sectional view of the mechanism of the internal combustion engine of the present invention, FIG. 2 is a vertical sectional view of the variable pulp timing mechanism, and FIG.
Direction arrow view, Figure 4 is a pulp timing diagram of the intake valve at partial load and full load. - 16...Crankshaft 34...Intake valve camshaft ゛54...Inner sleeve 60;...Outer sleeve 62.64...Slit 66.68...Roller bearing 70...Bearing support 78... Operating rod 84... Accelerator pedal Patent applicant Toyota Motor Corporation Patent agent Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Kyosuke Donakayama Patent attorney Akiyuki Yamaguchi Figure 1 Figure 4 TDC DC DC DC

Claims (1)

[Claims] An internal combustion engine having a camshaft dedicated to an intake valve has a pair of relatively rotatable sleeves, one on the camshaft side and the other on the power transmission member side of a timing pulley connected to the crankshaft, the sleeves intersecting each other. An intake air amount control device for an internal combustion engine, in which a roller bearing positioned in the slit is mounted on a support that can be reciprocated in the direction of a camshaft, and the support is connected to an accelerator pedal.