JP2955342B2 - Valve timing adjustment device for internal combustion engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a valve timing adjusting device for an internal combustion engine.

[Conventional technology]

Conventionally, a valve timing adjusting device for an internal combustion engine has a hydraulic piston built into a timing pulley of a camshaft,
Helical splines are formed on the outer circumference of the camshaft and the inner circumference of the timing pulley, each helical spline is meshed with the helical spline formed on the inner and outer circumferences of the piston, and the piston is moved in the axial direction of the camshaft by hydraulic pressure. (See, for example, Japanese Utility Model Laid-Open No. 1-174502).

Further, in order to obtain the above-mentioned effect on a plurality of camshafts at once, it is advantageous to use the same method as the above for the timing pulley of the crankshaft.

[Problems to be solved by the invention]

However, since a pulley for driving the auxiliary machine is provided on the crankshaft, if the pulley of the valve timing adjustment device is arranged separately from the drive pulley for the auxiliary machine, both pulleys and the pulley in the axial direction of the crankshaft are arranged. There is a problem that a mechanism (valve timing adjustment mechanism) for changing the relative angular position of the camshaft and the timing pulley is arranged, and the size of the engine is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide an auxiliary device operating torque transmitter for transmitting a driving torque from a crankshaft to an auxiliary device, a camshaft operating torque transmitter for transmitting a driving torque to a camshaft, and a rotational phase of the crankshaft and the camshaft. An object of the present invention is to provide a valve timing adjustment device for an internal combustion engine that can reduce the size of an engine when a valve timing adjustment mechanism that changes an angle is arranged.

[Means for solving the problem]

The present invention relates to a torque transmitting body for operating an auxiliary device for transmitting a driving torque to an auxiliary device side with respect to an end portion of a crankshaft of an internal combustion engine, and for operating a camshaft for transmitting a driving torque to a camshaft side. In a valve timing adjusting device for an internal combustion engine, a torque transmitting body and a valve timing adjusting mechanism for changing a rotation phase of a crankshaft and a torque transmitting body for operating a camshaft are arranged. The valve timing adjusting mechanism is connected to and fixed to a shaft end, is formed in a cylindrical shape so as to radially expand from the crankshaft end and return to the engine main body along the axial direction of the crankshaft. It is housed radially inward of the operating torque transmitting body, and radially outward of the accessory operating torque transmitting body, on the accessory side. A first operating connecting portion for transmitting dynamic torque is formed, the camshaft operating torque transmitting body extends from the valve timing adjusting mechanism, and an engine-side opening end of the auxiliary machine operating torque transmitting body. An internal combustion engine in which a second operating connecting portion for transmitting drive torque to the camshaft side is formed in a portion of the camshaft operating torque transmitting body exposed to the engine side, the portion being exposed on the engine side. The gist of the present invention is a valve timing adjusting device.

According to the present invention, the valve timing adjustment mechanism is housed radially inside the accessory-operating torque transmitting body and transmits the driving torque to the accessory side radially outside of the accessory-operating torque transmitting body. A first working connection is formed.

As a result, in the case where the auxiliary equipment operating torque transmitting body, the camshaft operating torque transmitting body, and the valve timing adjusting mechanism are provided at the end of the crankshaft in the axial direction of the crankshaft, the arrangement of each member and mechanism is also provided. The total length does not increase, and the engine is downsized. Also, the valve timing adjustment mechanism is housed in an auxiliary device operating torque transmitter fixed to the crankshaft, and is protected by the auxiliary device operating torque transmitter. The reliability of the valve timing adjustment mechanism disposed on the crankshaft, which is disposed and is likely to collide with an obstacle, can be improved.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a crankshaft 1 is rotatably supported on a cylinder block of an engine as an internal combustion engine. At the left end of the crankshaft 1, a screw hole 2 extending in the axial direction is provided. This screw hole 2
Is connected to an oil passage 3 that is open on the outer peripheral surface of the left end portion of the crankshaft 1 so that hydraulic oil is supplied into the screw hole 2 through the oil passage 3.

At the left end of the crankshaft 1, a hollow shaft 4 as a cylindrical inner member is attached. The hollow shaft 4 has a cylindrical shape with both left and right end surfaces opened, and a helical spline S1 is formed on the outer peripheral surface. or,
The hollow shaft 4 is integrally formed with a partition wall 4a that partitions the inside of the hollow shaft 4 to the left and right. The right portion of the hollow shaft 4 is fitted to the left portion of the crankshaft 1 with its axes aligned with each other, and the two are locked by the key 5 so that they cannot rotate relative to each other. A bolt insertion hole 6 is formed through the center of the partition wall 4a corresponding to the screw hole 2 of the crankshaft 1.

At the left side of the hollow shaft 4, an accessory driving pulley structure 7 as an accessory operating torque transmitting body is attached. The accessory drive pulley structure 7 includes a cylindrical portion 7a, a pulley portion 7b having a larger diameter than the cylindrical portion 7a, and a connecting portion connecting the cylindrical portion 7a and the pulley portion 7b. 7c. The right side of the cylindrical portion 7a of the auxiliary drive pulley assembly 7 is fitted into the left side of the hollow shaft 4 with their axes aligned with each other.

An auxiliary equipment drive belt 9 is mounted on a pulley portion 7b of the auxiliary equipment drive pulley assembly 7, and the auxiliary equipment drive belt 9 causes rotation of the crankshaft 1 to auxiliary equipment (alternator, refrigerating cycle compressor, etc.). To be transmitted. Further, a bolt insertion hole 10 is formed in the cylindrical portion 7 a of the accessory drive pulley structure 7 so as to correspond to the bolt insertion hole 6 of the hollow shaft 4.

Then, with the hollow shaft 4 fitted on the crankshaft 1 and the cylindrical portion 7a of the accessory drive pulley assembly 7 fitted on the hollow shaft 4, both bolt insertion holes 6, 10 are inserted.
A bolt 11 as a fixing member is inserted into the crankshaft 1, and the bolt 11 is screwed into the screw hole 2 of the crankshaft 1. Accordingly, the hollow shaft 4 and the accessory drive pulley structure 7 are fixed to the crankshaft 1 by the bolts 11, and the hollow shaft 4 and the accessory drive pulley structure 7 can rotate integrally with the rotation of the crankshaft 1. . still,
The bolt 11 has an oil passage 12 penetrating in the axial direction.

On the other hand, on the outer periphery of the right end of the hollow shaft 4, a cylindrical outer member and a timing pulley structure 13 as a torque transmitting member for operating the camshaft are rotatably supported. The timing pulley assembly 13 includes a pulley portion 13a as a second operation connection portion having a cylindrical shape slightly larger in diameter than the hollow shaft 4, a cylindrical rotation transmitting portion 13b larger in diameter than the pulley portion 13a, And a flange 13c formed at the left end of the portion 13b. The timing pulley structure 13 is fitted around the outer periphery of the right end of the hollow shaft 4 at the pulley portion 13a.

A timing belt 14 is mounted on a pulley portion 13a of the timing pulley structure 13, and the rotation of the crankshaft 1 is transmitted to a camshaft (not shown) via the timing belt 14. . Further, a lid member 15 is attached to the flange portion 13c. The lid 15 includes a cylindrical portion 15a and a flange portion 15b formed at the right end of the cylindrical portion 15a. The flange portion 15b is fitted into the flange portion 13c of the timing pulley assembly 13 with their axes aligned with each other. And is fixed by bolts 16.
Note that a helical spline S2 is formed on the inner peripheral surface of the rotation transmitting portion 13b.

A cap 17 is fixed to the left end of the cylindrical portion 7a of the accessory drive pulley assembly 7 with bolts 18.
17 closes the cylindrical portion 7a. The cylindrical portion 7a has a plurality of communication holes 19 communicating the inside and the outside of the cylindrical portion 7a. For this reason, through the oil passages 3 and 12
Hydraulic oil supplied into 7a passes through communication hole 19, and cylindrical portion 7a
Can flow out. Further, an annular oil seal 2 is provided between the outer peripheral surface of the cylindrical portion 7a and the inner peripheral surface of the cylindrical portion 15a of the lid member 15.
0 is interposed.

A piston 21 as a moving body is disposed in a space surrounded by the timing pulley structure 13, the hollow shaft 4, the accessory drive pulley structure 7, the lid member 15, and the oil seal 20. The piston 21 has a substantially cylindrical shape with left and right ends opened, and helical splines S3 and S4 are formed on the inner and outer peripheral surfaces thereof. Then, these helical splines S3 and S4 correspond to the timing pulley structure 13
And the helical splines S1 and S2 of the hollow shaft 4 respectively.

The hydraulic pressure of the hydraulic oil supplied through the communication hole 19 is applied to the left end face of the piston 21, and the urging force of the spring 22 is applied to the right end face of the piston 21. When the piston 21 moves in the axial direction of the crankshaft 1 due to the balance between the hydraulic pressure and the urging force of the spring 22, the timing pulley structure 13 rotates relative to the hollow shaft 4 due to the helical spline torsion. It works. FIG. 1 shows a state where the piston 21 has moved to the rightmost side, and FIG. 2 shows a state where the piston 21 has moved to the leftmost side. Helical spline S1 is hollow shaft 4, timing pulley structure 13 with helical spline S2, piston 2 with helical splines S3, S4
1, and a hydraulic system that drives the piston 21 forms a valve timing adjustment mechanism.

Incidentally, a cylindrical signal rotor 23 is fixed to the accessory drive pulley structure 7 with bolts 24, and a cylindrical portion 23a of the signal rotor 23 is slightly spaced from the outer circumference of the rotation transmitting portion 13b of the timing pulley structure 13. It is arranged in. A plurality of radial teeth 23b are formed at the right end of the signal rotor 23, and the rotation of the rotor 23 is detected by detecting passage of the teeth 23b by an electromagnetic pickup coil or the like.

Next, a procedure for mounting the valve timing adjusting device thus configured will be described.

First, the hollow shaft 4 is fitted inside the pulley portion 13a of the timing pulley structure 13. The spring 22 and the piston 21 are fitted between the hollow shaft 4 and the rotation transmitting portion 13b (to mesh with the helical spline), and then the lid member 15 is fixed to the flange portion 13c with bolts 16. Subsequently, the cylindrical portion 7a of the accessory drive pulley assembly 7 after the oil seal 20 is attached is fitted into the hollow shaft 4. Then, the signal rotor 23 is fixed to the pulley portion 7b with bolts 24.

In the assembled state, the hollow shaft 4 is externally fitted to the crankshaft 1. Then, the bolt 11 penetrates through the bolt insertion hole 10 of the accessory drive pulley structure 7 and the bolt insertion hole 6 of the hollow shaft 4 and is screwed into the screw hole 2 of the crankshaft 1. After that, the cap 17 is fixed to the accessory driving pulley structure 7 with the bolt 18.

Thus, the valve timing adjusting device of the internal combustion engine is assembled to the crankshaft 1.

During operation of the engine, the valve timing adjusting device is configured to apply hydraulic pressure from a hydraulic circuit (not shown) to an oil passage.
It is applied to the hydraulic chamber R on the left side of the piston 21 via 3, 12
The hydraulic pressure causes the piston 21 to move rightward against the urging force of the spring 22. At this time, as shown in FIG. 1, the timing pulley structure 13 rotates relatively to the hollow shaft 4 due to the twist of the helical spline. As a result, the valve timing of the engine is adjusted, and the start and end times of intake or exhaust according to the operating state are adjusted.

Further, the signal rotor 23 fixed to the accessory drive pulley structure 7 rotates in synchronization with the crankshaft 1, and the rotation speed of the crankshaft 1 is detected by detecting the rotation of the signal rotor 23.

As described above, in this embodiment, the hollow shaft 4 (cylindrical inner member) is externally fitted to the end of the crankshaft 1 in a state where the axes thereof are aligned with each other, and the timing pulley constituting body 13 ( The cylindrical outer member) is rotatably supported, and the hollow shaft 4 and the timing pulley structure
A piston 21 (moving body) is arranged between the piston 13 and the cylindrical part 7a of the accessory drive pulley structure 7 (an accessory operating torque transmitting body) is fitted into the hollow shaft 4 in a state where their axes are aligned with each other. Then, the two members were fixed immovably in the axial direction and the radial direction (rotational direction) with respect to the crankshaft 1 by bolts 11 (fixing members) penetrating the hollow shaft 4 and the accessory driving pulley structure 7. As a result, the valve timing adjustment device can be attached to the crankshaft provided with the accessory drive pulley structure with high accuracy.

Further, the hollow shaft 4 is supported by the inner peripheral portion of the pulley portion 13a of the timing pulley structure 13, and the pulley portion 13a
Since the timing belt 14 is mounted on the outer peripheral portion, the tension of the timing belt 14 acts on the bearing support, and the piston 21 can move smoothly in the axial direction without the timing pulley structure 13 being inclined.

In addition, the auxiliary drive pulley structure 7 is used for the crankshaft 1
The crankshaft 1 receives all the tension of the accessory drive belt 9 and the tension is
Does not adversely affect the relative rotation of the.

Further, in the axial direction of the crankshaft 1, it includes an auxiliary device driving pulley component 7 (an auxiliary device operating torque transmitting member), a timing pulley component 13 (a camshaft operating torque transmitting member), a piston 21, and the like. Even when the valve timing adjusting mechanism is provided at the end of the crankshaft 1, the piston 21 and the like constituting the valve timing adjusting mechanism are arranged radially inside the auxiliary device driving pulley structure 7, so that each structure 7 , 13, The total value of the arrangement lengths of the mechanisms does not become long. Therefore, the size of the engine can be reduced.

Further, the valve timing adjusting mechanism including the piston 21 and the like is housed in the auxiliary device driving pulley structure 7 fixed to the crankshaft 1 and protected by the auxiliary device driving pulley structure 7. Therefore, the reliability of the valve timing adjustment mechanism generally disposed on the crankshaft 1 which is disposed on the lower part of the engine and is likely to collide with an obstacle can be improved.

Note that the present invention is not limited to the above embodiment. For example, in the above embodiment, the rotation of the crankshaft 1 is transmitted to the camshaft by the timing belt 14, but is transmitted by the chain sprocket. You may.

Also, as shown in FIG. 3, the bolt 18 is eliminated from the cap 17 and the bolt 18 for sealing the oil pressure in the hydraulic chamber R in FIG. 1, and the female thread portion 26 is formed on the cap 25 itself. At the same time, the auxiliary drive pulley
27 may be formed and the cap 25 may be tightened and fixed.

Further, as shown in FIG.
A bolt with cap 28 in which the cap 11 and the cap 17 are integrated may be assembled. In this case, the oil passage of the bolt with cap 28
The reference numeral 29 does not penetrate the left end of the bolt 28, but branches radially from the middle to communicate with the hydraulic chamber R. In FIG. 4, the outer diameter dimension can be further reduced by changing the connection method between the timing pulley assembly 13 and the cover member 15 to caulking rather than bolt fixing shown in FIG. The rubber damper 30 can be arranged on the accessory drive pulley structure 7 by the reduced outer diameter.

3 and 4, the upper half from the axis L1 shows a state where the piston 21 has moved to the rightmost side, and the lower half shows a state where the piston 21 has moved to the leftmost side.

〔The invention's effect〕

As described in detail above, according to the present invention, in the axial direction of the crankshaft, the auxiliary equipment operating torque transmitter, the camshaft operating torque transmitter, and the valve timing adjusting mechanism are provided at the end of the crankshaft. Also in this case, the total value of the arrangement length of each member and mechanism does not increase, and the engine can be downsized.

Further, the valve timing adjustment mechanism is housed in an auxiliary device operating torque transmitter fixed to the crankshaft and is protected by the auxiliary device operating torque transmitter.
Generally, the reliability of the valve timing adjustment mechanism disposed on the crankshaft, which is disposed below the engine and is likely to collide with an obstacle, can be improved.

[Brief description of the drawings]

1 is a sectional view of a valve timing adjusting device of an internal combustion engine according to an embodiment, FIG. 2 is a sectional view of the same valve timing adjusting device, FIG. 3 is a sectional view of another example of a valve timing adjusting device of an internal combustion engine, FIG. 4 is a sectional view of another alternative example of a valve timing adjusting device for an internal combustion engine. 1 is a crankshaft, 4 is a hollow shaft as a cylindrical inner member, 7 is an accessory driving pulley structure as an accessory connecting member, 11 is a bolt as a fixing member, and 13 is a timing pulley as a cylindrical outer member. Structure, 21 is a piston as a moving body.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takeno Gono 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-60-243308 (JP, A) JP-A-2-248608 (JP, A) JP-A-63-21309 (JP, A) JP-A-1-174502 (JP, U) Patent 141169 (JP, C2) (58) Fields investigated (Int. Cl. ⁶ , DB name) F01L 1/34 F01L 1/02

Claims (1)

(57) [Claims] 1. An accessory operating torque transmitting body for transmitting driving torque to an auxiliary machine side with respect to an end of a crankshaft of an internal combustion engine, and a camshaft operating for transmitting driving torque to a camshaft side. A valve timing adjusting device for an internal combustion engine, wherein the torque transmitting member for operating an auxiliary device is provided with a valve timing adjusting mechanism for changing a rotation phase between a crankshaft and a torque transmitting member for operating a camshaft. The valve timing adjustment mechanism is connected and fixed to the end of the crankshaft, is formed in a cylindrical shape so as to radially extend from the end of the crankshaft, and return to the engine body along the axial direction of the crankshaft. The auxiliary device-side torque transmitting body is accommodated inside the auxiliary device-operating torque transmitting unit in the radial direction, A first operating connecting portion for transmitting a driving torque is formed; the camshaft operating torque transmitting body extends from the valve timing adjusting mechanism; and an engine-side opening end of the auxiliary machine operating torque transmitting body. And a second operation connecting portion for transmitting driving torque to the camshaft side is formed at a portion of the camshaft operation torque transmitting body exposed to the engine side. A valve timing adjusting device for an internal combustion engine, characterized in that: