US20020000213A1

US20020000213A1 - Valve timing adjusting apparatus for internal combustion engine

Info

Publication number: US20020000213A1
Application number: US09/886,263
Authority: US
Inventors: Katsuyuki Fukuhara; Mutsuo Sekiya
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1999-10-22
Filing date: 2001-06-22
Publication date: 2002-01-03
Also published as: WO2001029377A1

Abstract

A valve timing adjusting apparatus comprises: a housing 31 integrally provided to a timing pulley driven by an engine crank shaft, a shoe hosing 33 which is connected to the housing 31 and having a plurality of shoes 33a protruded from the inner surface of housing, and a rotor 34 which is rotatably accommodated in the she housing 33, wherein a plurality of vanes protrudedly provided on the external surface of the rotor divide the space made by the plurality of shoes 33a into an angle-delay hydraulic cabin and an angle-advance hydraulic cabin, and the rotor 34 is coaxially connectable to the camshaft 2. The valve timing adjusting apparatus further comprises: a protruded portion 46 protruding in the axial direction of the housing 31 on either one of the abutting surfaces of the rotor 34 and the housing 31, and a recess 47 to be fitted to the protruded portion 46 is formed in the other of the rotor 34 and the housing 31.

Description

CROSS-REFERENCE TO THE RELATED APPLICATION

This Application is a continuation of International Application No. PCT/JP99/05864, whose international filing date is Oct. 22, 1999, the disclosures of which Application are incorporated by reference herein, and which International Application was not published in English.[0001]

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a valve timing adjusting apparatus, which variably controls the timing for opening and/or closing either an intake valve or an exhaust valve in accordance with the driving state of an internal combustion engine.

2. Description of the Related Art

There have been proposed various vane-type valve timing adjusting apparatuses for internal combustion engine so far, a case in point being the one disclosed in Japanese Patent Application Laid-Open No. 9-60507.

FIGS. 1 and 2 are illustrations showing a conventional vane-type valve timing adjusting apparatus for internal combustion engine, which is mounted onto a camshaft of an internal combustion engine (hereinafter may be referred to just as an “engine”), wherein FIG. 1 is a longitudinal sectional view of the valve-timing adjusting apparatus, and FIG. 2 is a sectional view observed along the line II-II of FIG. 1. In FIG. 1,

reference numeral

1 denotes a chain sprocket, which receives a rotational force transmitted from a crank shaft (not shown) functioning as a drive shaft of the engine by way of a chain (not shown), and rotates in synchronism with the crank shaft. The camshaft 2 functioning as a slave shaft receives the driven force transmitted from the chain sprocket 1, and opens and/or closes at least one of an intake valve (not shown) and an exhaust valve (not shown). The camshaft 2 is rotatable with respect to the chain sprocket 1 within a predetermined angle.

As shown in FIG. 1, the

chain sprocket

1 and a shoe housing 3 functioning as a housing member, and also a front plate 4 functioning as a covering member are coaxially fixed by a bolt 5. The inner surface of the boss la of the chain sprocket 1 is engaged with the end portion 2 a of the camshaft 2 in a relatively rotatable manner. The position of the shoe housing 3 and that of the front plate 4 in the rotational angular direction are predetermined by a knock pin 6, whereas the position of the chain sprocket 1 and that of the shoe housing 3 in the rotational angular direction are predetermined by another knock pin (not shown).

As shown in FIGS. 1 and 2, the

shoe housing

3 contains

trapezoidal shoes

3 a and 3 b facing to each other. The opposing faces of these

shoes

3 a and 3 b are formed respectively in a sectionally circular arc shape, and in two gaps made by these

shoes

3 a and 3 b in the circumferential direction thereof, there are formed fan shape spaces for respectively accommodating

vanes

7 a and 7 b (later explained) of a vane rotor 7. The vane rotor 7 is generally composed of the fan shape vanes 7 a and 7 b and also a support member 7 c for supporting these

vanes

7 a and 7 b, which support member being integrally fixed to the camshaft 2 by a bolt 8. The

vanes

7 a and 7 b are rotatably accommodated in the fan shape spaces formed in the circumferential direction of the

respective shoes

3 a and 3 b. The in-low section 7 d of the vane rotor 7 is coaxially engaged with the end portion 2 a of the camshaft 2, and the position of the vane rotor 7 and that of the camshaft 2 in the rotational angular direction thereof are predetermined by a knock pin (not shown). The cylindrical protruded portion 9 integrally fixed to the vane rotor 7 is fitted into the inner peripheral surface of the front plate 4 in a relatively rotatable manner. There are formed

small clearances

10 and 11 between the external peripheral surface of the vane rotor 7 and the inner peripheral surface of the show housing 3, wherein the vane rotor 7 and the shoe housing 3 are formed in a relatively rotatable manner. There are formed a retarding hydraulic chamber 12 between the shoe 3 a and the vane 7 a, and a retarding hydraulic chamber 13 formed between the shoe 3 b and the vane rotor 7 b, whereas there are formed an advancing hydraulic chamber 14 between the shoe 3 a and the vane 7 b, and also an advancing hydraulic chamber 15 between the shoe 3 b and the vane 7 a. Further, there are formed oil paths at the opposite axial end surfaces of the support member 7 c of the vane rotor 7, wherein at its abutting section against the cylindrical protruded portion 9, an oil path 16 is provided as a groove-shape path is formed, whereas at its abutting portion against the camshaft 2, an oil path 17 is provided as a groove-like path is formed, both shifted from each other along the respectively circumferential directions in the form of a letter “C”. The oil path 16 is connected to the retarding

hydraulic chambers

12 and 13 by way of

other oil paths

18 and 19, and is further connected to an oil chamber (not shown) by way of another oil path 20. The oil path 17 is connected to the advancing angle

hydraulic chambers

14 and 15 by way of

other oil paths

22 and 23. An oil path 24 is connected to an oil path 25 formed within the camshaft 2 at the abutting portion of the support member 7 c against the camshaft 2 in the axial direction, wherein the oil path 16 is connected to the oil path 24 at the abutting portion of the support member 7 c against the cylindrical protruded portion 9. The oil path 17 is connected to an oil path (not shown) formed within the camshaft 2 at the abutting portion of the support member 7 c against the camshaft 2.

By this construction above, the

camshaft

2 and the vane rotor 7 are formed such that they are coaxially and relatively rotatable with respect to all the chain sprocket 1, the shoe housing 3 and also the front plate 4. Specially, the vane rotor 7 maintains its coaxial position with the shoe housing 3 by suppressing the

shoes

3 a and 3 b towards the radially external direction of the vane rotor 7 by use of a chip seal 27 attached to the groove portion 7 d formed in the external peripheral wall of its support portion 7 c.

It is to be noted that when attaching the valve timing adjusting apparatus as constructed above to the engine main body, after the above-mentioned

vane rotor

7 is mounted to the shoe housing 3 and the front plate 4 in a coaxially and relatively rotatable manner, the thus formed component is transported to an engine body assembling factory as an engine component in many cases. At the time of this transport, external forces such as vibration and so on can be exerted to the components such as the above-mentioned vane rotor 7 and so on.

However, in the case where such an external force as the vibration during the transport is exerted against the urging force of the

chip seal

27 toward the radial direction of the above-mentioned vane rotor 7, the coaxial position of the vane rotor 7 with respect to the shoe housing 3 and so on is erroneously shifted, thereby to cause such a problem that the mountability of the vane rotor 7 onto the camshaft 2 becomes deteriorated.

The present invention has been proposed to solve the problems aforementioned, and it is an object of the present invention to provide a valve timing adjusting apparatus for internal combustion engine which is provided with a means for regulating the positional relation in the radial direction between the rotor and the housing, and also that between the rotor and the covering member.

SUMMARY OF THE INVENTION

The valve timing adjusting apparatus according to the present invention is constructed in such a manner that it comprises: a housing integrally formed with a rotational member that is driven by a crankshaft at an engine side, a shoe case, which is connected to the housing and having a plurality of shoes protruded from the inner surface of the shoe case, and a rotor which is rotatably accommodated in the shoe case, and is formed with a plurality of vanes protruding from its external peripheral surface, which vanes dividing each of the spaces between the plurality of adjacent shoes into a first hydraulic cabin and a second hydraulic cabin, wherein the rotor is coaxially connectable with a camshaft for driving a valve of an engine system to be opened and/or shut, wherein either one of the abutting surfaces between the rotor and the housing is formed with a protruded portion projecting in the axial direction of the housing, and the other of the abutting surfaces is formed with a recess to be fitted with the protruded portion. Due to this construction, the relative movements of the rotor and the housing in the radial directions can be regulated by the fitting of the protruded portion and the recess, and thus, since the relative movements of the case and the rotor in the radial direction can also be regulated, even if an external force is applied during the transport thereof, the coaxial position of the rotor with the case can be securely maintained, and thus the mountability thereof onto the camshaft of the engine main body can be greatly improved.

Further, according to the present invention, the protruded portion and the recess can be fitted in a slidable manner in the axial direction of either the rotor or the housing. Due to this construction, the fitting of the protruded portion with the recess can be greatly facilitated.

Further, according to the present invention, the protruded portion is a first annular projection coaxially formed with the rotor on a first boss section which is provided at either one of the axial opposite end portions of the rotor, and the recess is formed in a covering member covering one end of the axial opposite end portions and slidably fitted with the first annular projection, which recess being a first through hole coaxial with the covering member. Due to this construction, the relative movements of the covering member and the rotor in the radial direction are regulated by the fitting of the first through hole with the first annular protruded portion, and since the positional relation of the casing connected to the covering member and the rotor is regulated in the radial direction, even if an external force is applied thereto during the transport thereof, the coaxial position of the rotor with respect to the casing member can be maintained, and thus the mountability thereof onto the camshaft of the engine main body side can be greatly improved.

Still further, according to the present invention, the protruded portion further contains a second annular projection coaxially formed with the rotor on a second boss section which is provided at the other end of the axial opposite end portions, and the recess further contains a second through hole coaxially formed in the housing, and silidablly fitted with the second annular projection. Due to this construction, in addition to the regulation of the positional relation between the casing and the rotor, the movement of the rotor and the housing in the radial direction can also be regulated by fitting of the second annular protruded portion and the second through hole, so that even if an external force is applied thereto during the transport thereof, the coaxial position of the rotor with respect to the housing can be securely maintained, and thus the mountability thereof onto the camshaft of the engine main body side can be greatly improved.

Yet still further, the valve timing adjusting apparatus according to the present invention is constructed in such a manner that it comprises: housing integrally formed with a rotational member that is driven by a crankshaft at an engine side, a shoe case, which is connected to the housing and having a plurality of shoes protruded from the inner surface of the shoe case, and a rotor which is rotatably accommodated in the shoe case, and is formed with a plurality of vanes protruding from its external peripheral surface, which vanes dividing each of the spaces between the plurality of adjacent shoes into a first hydraulic cabin and a second hydraulic cabin, wherein the rotor is coaxially connectable with a camshaft for driving a valve of an engine system to be opened and/or shut, a covering member for covering either one of the opposite axial ends of the rotor, and a bias means, which is disposed at the opposite side of the rotor and the shoe case with respect to the covering member, and urges the rotor against the shoe case either in the advancing direction or the retarding direction, wherein either one of the abutting surfaces between the rotor and the housing is formed with a protruded portion projecting in the axial direction of the housing, and the other of the abutting surfaces is formed with a recess to be fitted with the protruded portion, wherein one part of the protruded portion is a fixed end of the bias means. Due to this construction, the relative movements of the rotor and the housing in the radial directions can be regulated by the fitting of the protruded portion and the recess, whereby even if an external force is applied thereto during the transport thereof, the coaxial position of the rotor with respect to the housing can be securely maintained, and thus the mountability thereof onto the camshaft of the engine main body side can be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view showing a conventional vane-type valve timing adjusting apparatus. [0018]
FIG. 2 is a sectional view observed along the line II-II of FIG. 1. [0019]
FIG. 3 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a first embodiment of the present invention. [0020]
FIG. 4 is a sectional view observed along the line IV-IV of FIG. 3. [0021]
FIG. 5 is a partly magnified sectional view showing the portions V[0022] 1 and V2 of FIG. 4.
FIG. 6 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a second embodiment of the present invention. [0023]
FIG. 7 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a third embodiment of the present invention.[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Several embodiments for carrying out best the present invention are now explained with reference to attached drawings, in order to explain the present invention to details. [0025]

First Embodiment

FIG. 3 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a first embodiment of the present invention. FIG. 4 is a sectional view observed along the line IV-IV of FIG. 3, and FIG. 5 is a partly magnified sectional view showing the portions V[0026] 1 and V2 of FIG. 4. Note that as to the components of a valve timing adjusting apparatus for internal combustion engine according to the first embodiment, the same or similar members as or to those in FIGS. 1 and 2 are put the same reference numerals for omitting a repetition of the same explanation.
In these figures, [0027] reference numeral 30 denotes a timing pulley as a rotating member that is driven in synchronism with the rotation of the engine by way of an endless belt (not shown), and numeral 31 denotes a housing of a substantially disk shape integrally formed with the timing pulley 30. The center portion of the housing 31 is formed with a through hole 32 so as to be fitted with the camshaft 2 inserted therethrough. There is provided a shoe housing 33 as a casing and the vane rotor 34 accommodated in this shoe housing 33 between the housing 31 and the front plate 4. The inner peripheral surface of the shoe housing 33 is formed with four shoes 33 a, 33 b, 33 c and 33 d, whereas the external peripheral surface of the vane rotor 34 is formed with four vanes 34 a, 34 b, 34 c and 34 d. In this configuration, the vane 34 is accommodated in the fan shape space between the shoes 33 a and 33 b, the vane 34 b is accommodated in the fan shape space between the shoes 33 b and 33 c, the vane 34 c is accommodated in the fan shape space between the shoes 33 c and 33 d, and the vane 34 d is accommodated in the fan shape space between the shoes 33 d and 33 a, wherein the respective vanes 34 a, 34 b, 34 c and 34 d divide each of the fan shape spaces into the retarding hydraulic chamber 35 as a first hydraulic chamber and the advancing hydraulic chamber 36 as a second hydraulic chamber. The mutually adjacent retarding hydraulic chambers 35 and the advancing hydraulic chambers 36 are hampered from being interconnected by the chip seal 37 provided to each of the end portions of the shoes 33 a, 33 b, 33 c and 33 d, and by the chip seal 38 provided to each of the end portions of the vanes 34 a, 34 b, 34 c and 34 d. It is to be noted that reference numeral 39 denotes a back spring that makes each of the chip seals 37 to be brought into contact with the external surface of the vane rotor 34, and a similar back spring (not shown) is provided also to each of the other chip seals 38.
In FIG. 4, numeral [0028] 40 denotes a plunger slidably disposed along the axial direction in the through hole 31 a of the housing 31, numeral 41 denotes a spring that is disposed in the through hole 31 a of the housing 31, urging the plunger 40 into the fitting hole 42 of the vane rotor 34, and numeral 43 denotes a plunger oil path for feeding oil into the fitting hole 42 of the vane rotor 34 and/or exhausting the used oil from the fitting hole 42. In the case where oil pressure is not supplied to this plunger oil path 43, the plunger 40 is fitted into the fitting hole 42 of the vane rotor 34 by the urging force of the spring 41, whereby the relative rotation of the vane rotor 34 and the housing 31 is suppressed. On the other hand, in the case where oil pressure is supplied to the plunger oil path 43, the thus supplied oil pressure pushes the plunger 40 rearward against the urging force of the spring 41, and the plunger 40 is separated from the fitting hole 42 of the vane rotor 34, whereby the suppression of relative rotation of the vane rotor 34 and the housing 1 is released.
Note that [0029] reference numeral 44 denotes a first oil path provided within the camshaft 2, and is connected to the retarding hydraulic chamber 35 for shifting the vane rotor 34 in the retarding direction, whereas reference numeral 45 denotes a second oil path provided also within the camshaft 2, and is connected to the advancing hydraulic chamber 36 for shifting the vane rotor 34 in the advancing direction.
In FIG. 5, numeral [0030] 46 denotes a protruded portion coaxially formed with the vane rotor 34 on the abutting surface at which the vane rotor 34 comes into contact with the housing 31, and projects along the axial direction of the vane rotor 34, whereas numeral 47 denotes a recess portion that is formed coaxially with the housing 31 at the abutting side of the through hole 32 of the housing 31 at which the housing 31 comes into contact with the bane rotor 34, and is fitted with the protruded portion 46. The inner surface 47 a of this recess 47 and the external surface 46 a of the protruded portion 46 are, when the housing 31 and the vane rotor 34 are to be fitted, slidably fitted in the axial direction of the vane rotor 34, and the vane rotor 34 and the housing 31 are relatively rotatable. Note that the front plate 4, the shoe housing 33 and the housing 31 are integrally fixed by a bolt 5.
Further, the center portion of the protruded [0031] portion 46 of the vane rotor 34 is formed with a fixing recess 48 for receiving and fixing the end portion 2 a of the camshaft 2, and an opening of this fixing recess 48 is formed with a slant portion 48 a for guiding the end portion 2 a of the camshaft 2 when inserting the camshaft 2 thereto.
Next, the method of mounting the above-explained valve-timing adjusting apparatus to the engine body is explained as below. [0032]
First, the [0033] vane rotor 34 is accommodated in the shoe housing 33, and the front plate 4 is attached to the end portion of these vane rotor 34 and shoe housing 33. Thereafter, when attaching the vane rotor 34 to the housing 31, the protruded portion 46 of the vane rotor 34 is fitted into the recess 47 of the housing 31 thereby to compose an engine part, and the thus composed engine part is transported to the assembling factory of the engine body. Note that the protruded portion 46 and the recess 47 are fitted in a slidable manner along the axial direction of the vane rotor 34, and further the vane rotor 34 and the housing 31 are made relatively rotatable, although the vane rotor 34 is delimited its movement in the radial direction by this fitting operation of the protruded portion 46 and the recess 47. Thus, even if an eternal force is exerted in the radial direction of the vane rotor 34 against the urging force of the chip seals 37 and 38 during the transport thereof, the displacement of the coaxial point of the vane rotor 34 with respect to the housing 31 can securely be prevented, so that the mountability of the vane rotor 34 onto the camshaft 2 can be greatly improved. Thereafter, at the engine body assembling factory, one end portion 2 a of the camshaft 2 is inserted into the through hole 32 of the housing 31. Here, the end portion 2 a of the camshaft 2 is inserted into the recess 48 of the vane rotor 34 coaxially mounted to the housing 31, wherein the end portion 2 a of the camshaft 2 is securely guided into the fixing recess 48 owing to the slant portion 48 a, and is fixed to the vane rotor 34 by a bolt 49 in a coaxial manner.
Next, the operation of the valve timing adjusting apparatus for internal combustion engine is now explained below. [0034]
First, in the case where the [0035] camshaft 2 is to be retarded in terms of timing with respect to the rotation angle of the timing pulley 30, oil is provided from an oil providing source (not shown) into the retarding hydraulic chambers 35 out of the two types of hydraulic chambers; namely the advancing hydraulic chambers 36 and the retarding hydraulic chambers 35, which are dividedly formed by the vanes 34 a, 34 b, 34 c and 34 d, and at the same time oil is exhausted from the advancing hydraulic chambers 36, whereby the camshaft is rotated, taking advantage of the difference of oil pressures at the respective sides of each of the vanes 34 a, 34 b, 34 c and 34 d. On this occasion, when the timing pulley 30 is rotated, the plunger 40 urged toward the camshaft 2 by the spring 41 is inserted into the fitting hole 42 of the vane rotor 34, and thus the relative rotation between the camshaft 2 which is firmly connected to the vane rotor 34 and the timing pulley 30 is suppressed.
As explained above, since it is intended according to this first embodiment that the coaxial position of the [0036] vane rotor 34 with respect to the housing 31 can be secured by fitting the protruded portion 46 provided to the vane rotor 34 in the axial direction into the recess 47 provided in the housing 31, the mountability of the vane rotor 34 onto the camshaft 2 can be greatly improved.
It should be noted that although in this embodiment the recess is formed at the [0037] housing 31 side and the protruded portion is provided at the vane rotor 34 side, the protruded portion can be provided at the housing 31 side, and the recess can be formed at the vane rotor 34 side, but on condition that the relative rotations of the housing 31 and the vane rotor 34 are not thereby delimited. Even in this case, the displacement of the coaxial point of the vane rotor 34 with respect to the housing 31 can securely be prevented, so that the mountability of the vane rotor 34 onto the camshaft 2 can be greatly improved.

Second Embodiment

FIG. 6 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a second embodiment of the present invention. Note that the same or similar members as or to those in FIGS. [0038] 3, at and 5 are put the same reference numerals for omitting a repetition of the same explanation.
The technical feature of this second embodiment resides in that the [0039] vane rotor 34 is fitted not only with the housing 31 in the valve-timing adjusting apparatus to be attached to the air intake side of an engine, just as the first embodiment, but also fitted with the front plate at That is, the protruded portion 46 of the vane rotor 34 is largely protruded much more than the case of the first embodiment so as to be a boss section (first boss), and threads through the recess 47 of the housing 31. The external peripheral surface 46 a of the vane rotor 34 and the inner peripheral surface 47 a of the recess 47 are fitted in an axially slidable manner, and the vane rotor 34 and the housing 31 are set in the relatively rotatable manner.
The center portion of the [0040] vane rotor 34 is formed with a cylindrical protruded portion 50 projecting in the axial direction as a boss section (second boss) at the opposite side of the protruded portion 46, and the center portion of the front plate at is formed with a through hole 51. The external peripheral surface 50 a of the protruded portion 50 and the inner peripheral surface 51 a of the through hole 51 are slidably fitted in the axial direction of the vane rotor 34, and the vane rotor 34 and the front plate at are formed in the relatively rotatable manner. Note that the front plate at, the shoe housing 33 and the housing 31 are integrally fixed by a bolt 5.
Due to the construction as explained above, in this second embodiment, not only the protruded [0041] portion 46 of the vane rotor 34 is fitted to the recess 47 of the housing 31, but the protruded portion 50 of the vane rotor 34 is also fitted into the through hole 51 of the front plate at, whereby the coaxial point of the vane rotor 34 with respect to the housing 31 and the front plate at can securely be maintained.

Third Embodiment

FIG. 7 is a longitudinal sectional view showing an important portion of the valve timing adjusting apparatus according to a third embodiment of the present invention. Note that the same or similar members as or to those of the valve timing adjusting apparatus according to the first and second embodiments as shown in FIGS. [0042] 3 to 6 are put the same reference numerals for omitting a repetition of the same explanation.
The technical feature of this third embodiment resides in that in the valve-timing adjusting apparatus to be attached to the air exhausting side of an engine, two boss sections of the [0043] vane rotor 34 are fitted both with the housing 31 and a later-explained unit cover. That is, the protruded portion 46 provided at one axial end surface of the vane rotor 34 is fitted into the recess 47 of the housing 31. Further, the other protruded portion 50 of the vane rotor 34 is fitted into the first and a second through holes 52 a and 53 a, which are formed in the center portion of a first plate 52 attached to both the shoe housing 33 and the other axial end surface of the vane rotor 34, and in the center portion of the second plate 53 attached to the surface of the first plate 52, respectively in the coaxial manner. These first and second plates 52 and 53 are fixed to the housing 31 and the vane rotor 34 by a fixing bolt 54. The outer periphery of the first plate 52 is bent to the direction opposite to the vane rotor 34 to make a bent portion 52 b, and this bent portion 52 holds the second plate 53 and the covering member 55, sandwiching the second plate 53 between the bent portion 52 and the covering member 55. The covering member 55 contains a third through hole 55 a for threading therein a bolt 56 used for coaxially fixing the vane rotor 34 and the camshaft 2, and also an accommodating section 55 b that encloses the third through hole 55 a therein, and also accommodates a spring as a bias means for urging the vanes 34 a, 34 b, 34 c and 34 d toward the retarding direction or advancing direction with respect to the shoe housing 33. The spring 57 is wound around the external peripheral portion of the protruded portion 50 of the vane rotor 34 fitted both with the first through hole 52 a of the first plate 52 and the second through hole 53 a of the second plate 53. The fixed end 57 a of the spring 57 is abutted against the notched portion 50 b of the protruded portion 50, whereas the top end portion 50 c of the protruded portion 50 is abutted against the inner peripheral brim of the third hole 55 a of the covering member 55. Note that the first plate 52, the second plate 53 and the covering member 55 configure together a unit cover 58. Further, In FIG. 7, reference numeral 59 denotes a holder for positioning the spring 41 that urges the plunger 40 for suppressing the relational movements of the shoe housing 33 and the vane rotor 34.
Since in this third embodiment of the present invention the protruded [0044] portion 46 of the vane rotor 34 is fitted into the recess of the housing 31, whereas the other protruded portion 50 of the vane rotor 34 is fitted into the first through hole 52 a of the first plate 52 and the second through hole 53 a of the second plate 53, there is such an effect that the coaxial position of the vane rotor 34 with respect to the housing 31 and to the unit cover 58 can be securely maintained.
Further, in this third embodiment, since it is arranged such that the fixed end [0045] 57 a of the spring 57 is abutted against the notched portion 50 b of the protruded portion 50 of the vane rotor 34, and the urging force of the spring 57 is applied directly to the vane rotor 34, there is such an effect that the components at the above two fitting portions are prevented from slipping off in the axial direction.
As explained heretofore, the valve timing adjusting apparatus according to the present invention is capable of maintaining the coaxial position of the rotor with respect to both the casing and the housing by delimiting the positional relation between the rotor and the housing, and that between the rotor and the covering member in the radial direction, whereby the mountability thereof onto the camshaft can be greatly improved. [0046]

Claims

What is claimed is:

1. A valve timing adjusting apparatus comprising:

a housing integrally formed with a rotational member that is driven by a crankshaft at an engine side,

a shoe case, which is connected to said housing and having a plurality of shoes protruded from the inner surface of said shoe case, and

a rotor which is rotatably accommodated in said shoe case, and is formed with a plurality of vanes protruding from its external peripheral surface, said vanes dividing each of the spaces between the plurality of adjacent shoes into a first hydraulic cabin and a second hydraulic cabin, wherein said rotor is coaxially connectable with a camshaft for driving a valve of an engine system to be opened and/or shut,

wherein either one of the abutting surfaces between said rotor and said housing is formed with a protruded portion projecting in the axial direction of the housing, and the other of said abutting surfaces is formed with a recess to be fitted with said protruded portion.

2. The valve timing adjusting apparatus according to claim 1 characterized in that said protruded portion and said recess can be fitted in a slidable manner in the axial direction of either said rotor or said housing.

3. The valve timing adjusting apparatus according to claim 1, wherein said protruded portion is a first annular projection coaxially formed with said rotor on a first boss section which is provided at either one of the axial opposite end portions of said rotor, and said recess is formed in a covering member covering one end of the axial opposite end portions and slidably fitted with said first annular projection, said recess being a first through hole coaxial with said covering member.

4. The valve timing adjusting apparatus according to claim 3, wherein said protruded portion further contains a second annular projection coaxially formed with said rotor on a second boss section which is provided at the other end of said axial opposite end portions, and said recess further contains a second through hole coaxially formed in said housing, and silidablly fitted with said second annular projection.

5. A valve timing adjusting apparatus comprising:

housing integrally formed with a rotational member that is driven by a crankshaft at an engine side,

a covering member for covering either one of the opposite axial ends of said rotor, and

a bias means, which is disposed at the opposite side of said rotor and said shoe case with respect to said covering member, and urges said rotor against said shoe case either in the advancing direction or the retarding direction,

wherein either one of the abutting surfaces between said rotor and said housing is formed with a protruded portion projecting in the axial direction of the housing, and the other of said abutting surfaces is formed with a recess to be fitted with said protruded portion, wherein one part of said protruded portion is a fixed end of said bias means.