Valve timing change device

Abstract

To share components of a valve timing change device and reduce the cost thereof.SOLUTION: Each of valve timing change devices M1, M2 for changing opening / closing timing for an intake valve or an exhaust valve to be driven by a camshaft includes a first rotor 20 or 120 rotatable around an axis line S of the camshaft, a second rotor 10 or 110, 30 rotatable in a predetermined angle range relative to the first rotor and adapted to be integrally rotated with the camshaft, and a rotation energizing spring 50 having one end 51 locked to the first rotor and the other end 52 locked to the second rotor to energize the second rotor to be rotated around the axis line relative to the first rotor, the second rotor 30 including a plurality of locking parts 34a, 34b for selectively locking the other end of the rotation energizing spring.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a variable valve timing device that changes the opening and closing timing (valve timing) of an intake valve or an exhaust valve of an internal combustion engine in accordance with an operating condition. [Background technology]

[0002] A known conventional valve timing change device includes a housing rotor that rotates synchronously with the crankshaft on the axis of the camshaft, a vane rotor that rotates integrally with the camshaft and can rotate relatively within a predetermined angular range with respect to the housing rotor, and a torsion coil spring that exerts a rotational biasing force around the axis of the camshaft, where one end of the torsion coil spring is engaged with a pin of the housing rotor and the other end is engaged with a fixing groove in the vane rotor, biasing the vane rotor to the advance side relative to the housing rotor (see, for example, Patent Document 1).

[0003] Another known valve timing change device includes a housing rotor that rotates synchronously with the crankshaft on the axis of the camshaft, a vane rotor that rotates integrally with the camshaft and can rotate relatively within a predetermined angular range with respect to the housing rotor, a washer that is positioned adjacent to the front face of the vane rotor and fixed to the camshaft with a bolt, a stopper pin that regulates the relative rotation of the washer and the vane rotor about the axis, and a spiral spring that exerts a rotational biasing force about the axis of the camshaft, wherein the spiral spring has an outer peripheral end that engages with a convex portion of the housing rotor and an inner peripheral end that engages with a locking groove in the washer, and biases the vane rotor in the advance direction relative to the housing rotor (see, for example, Patent Document 2).

[0004] In the above-mentioned valve timing change device, a dedicated torsion coil spring or spiral spring is set as the rotational biasing spring for each device, and dedicated locking portions are provided on the housing rotor and the vane rotor. In other words, the rotational biasing spring is set for each internal combustion engine specification in accordance with the rotational direction of the camshaft or the set load. Therefore, if the rotation direction of the camshaft differs or the set load of the rotational biasing spring differs depending on the specifications of the internal combustion engine, it is necessary to set multiple rotational biasing springs corresponding to each specification, and the increase in the number of parts leads to an increase in management labor and costs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-325758 A [Patent Document 2] Patent No. 6015604 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been achieved in consideration of the above-mentioned problems in the conventional technology, and has an object to provide a valve timing changing device which allows parts to be shared and reduces costs. [Means for solving the problem]

[0007] The valve timing change device of the present invention changes the opening and closing timing of an intake valve or an exhaust valve driven by a camshaft. valve A timing change device, comprising: a first rotor rotatable about an axis of a camshaft; The vane rotor is accommodated in the first rotor, and the annular spacer is joined to the vane rotor and positioned. A second rotor is rotatable relative to the first rotor within a predetermined angle range and rotates integrally with the camshaft. A second rotor is rotatably biased about an axis of the first rotor. times Equipped with a biasing spring, the first rotor includes a one-end locking portion that locks one end of the rotational biasing spring, and the annular spacer includes a first other-end locking portion that locks the other end of the rotational biasing spring to correspond to a first specification in which the rotational biasing spring exerts a rotational biasing force in one direction about the axis, a second other-end locking portion that locks the other end of the rotational biasing spring to correspond to a second specification in which the rotational biasing spring exerts a rotational biasing force in the other direction about the axis, a first positioning portion that is positioned about the axis with respect to the vane rotor to correspond to the first specification, and a second positioning portion that is positioned about the axis with respect to the vane rotor to correspond to the second specification, and the first other-end locking portion, the second other-end locking portion, the first positioning portion, and the second positioning portion are arranged so that the rotational biasing spring is assembled with a set load that exerts the same rotational biasing force in the first specification and the second specification. It is composed of:

[0012] In the above valve timing change device, the annular spacer may include a notch formed in the cylindrical portion, the notch defining a first other-end engaging portion at one side edge and a second other-end engaging portion at the other side edge.

[0013] In the above valve timing change device, a configuration may be adopted in which the housing rotor includes an opening that allows the annular spacer to protrude in the axial direction and an outer wall that defines the opening, and the rotational biasing spring is a spiral spring that is arranged along the outer wall and has one end engaged with a one-end engaging portion provided on the outer wall and the other end engaged with a first other-end engaging portion or a second other-end engaging portion of the annular spacer. Effect of the Invention

[0018] According to the variable valve timing device having the above-mentioned configuration, it is possible to achieve common use of parts, and therefore it is possible to achieve a reduction in the cost of the device. [Brief description of the drawings]

[0019] [Figure 1] 1 is an external perspective view showing a state in which a rotational biasing spring exerts a rotational biasing force in one direction (CW direction) in a valve timing changing device according to a first embodiment of the present invention. FIG. [Diagram 2] FIG. 2 is a front view of the variable valve timing device according to the first embodiment in a state where it is assembled in a first specification. [Diagram 3] FIG. 2 is an exploded perspective view of the variable valve timing device according to the first embodiment, which is assembled in a first specification, viewed obliquely from the front. [Figure 4] FIG. 2 is an exploded perspective view of the variable valve timing device according to the first embodiment, which is assembled in a first specification, viewed obliquely from the rear. [Diagram 5] 1 is a cross-sectional view of a variable valve timing device according to a first embodiment assembled in a first specification, taken along a plane passing through the axis of a camshaft. FIG. [Figure 6] 1 is a perspective view showing an annular spacer included in a valve timing changing device according to a first embodiment, as viewed obliquely from the front. FIG. [Figure 7] 1 is a perspective view showing an annular spacer included in a valve timing changing device according to a first embodiment, as viewed obliquely from the rear. FIG. [Figure 8]2 is a front view of an annular spacer included in the valve timing changing device according to the first embodiment. FIG. [Figure 9] FIG. 11 is a front view showing one end engaging portion of a housing rotor, a first other end engaging portion and a first positioning portion defined by a cutout portion of an annular spacer, and a rotation biasing spring in a valve timing change device according to the first embodiment assembled in accordance with a first specification. [Figure 10] 1 is a cross-sectional view showing a state in which a vane rotor is in a most retarded position in a valve timing variable device according to a first embodiment assembled in accordance with a first specification. FIG. [Figure 11] 2 is a cross-sectional view showing a state in which the vane rotor is in a most advanced position in the valve timing variable device according to the first embodiment assembled in accordance with a first specification. FIG. [Figure 12] 10 is an external perspective view showing a state in which the valve timing changing device according to the first embodiment of the present invention is assembled in a second specification in which the rotational biasing spring exerts a rotational biasing force in the other direction (CCW direction). FIG. [Figure 13] FIG. 4 is a front view of the variable valve timing device according to the first embodiment in a state where it is assembled in a second specification. [Figure 14] FIG. 2 is an exploded perspective view of the variable valve timing device according to the first embodiment, which is assembled in a second specification, viewed obliquely from the front. [Figure 15] FIG. 2 is an exploded perspective view of the variable valve timing device according to the first embodiment, which is assembled in a second specification, viewed obliquely from the rear. [Figure 16] FIG. 11 is a front view showing one end engaging portion of the housing rotor, the second other end engaging portion and second positioning portion defined by the cutout portion of the annular spacer, and a rotational biasing spring in the valve timing change device of the first embodiment assembled in the second specification. [Figure 17] FIG. 11 is a front view showing a valve timing change device according to a second embodiment of the present invention, illustrating the relationship between the rotational bias spring, one end locking portion of the housing rotor (front housing), and the first other end locking portion of the annular spacer when the rotational bias spring is assembled in a first specification in which the rotational bias spring exerts a rotational bias force in one direction (CW direction). [Figure 18] FIG. 11 is a front view showing a valve timing change device according to a second embodiment of the present invention, illustrating the relationship between the rotational bias spring, one end locking portion of the housing rotor, and the second other end locking portion of the annular spacer when the rotational bias spring is assembled in a second specification in which the rotational bias spring exerts a rotational bias force in the other direction (CCW direction). [Figure 19] FIG. 13 is a front view showing a valve timing change device according to a third embodiment of the present invention, illustrating the relationship between the rotational bias spring, the first one-end engaging portion of the housing rotor, and the other end engaging portion of the annular spacer when the rotational bias spring is assembled in a first specification in which the rotational bias spring exerts a rotational bias force in one direction (CW direction). [Figure 20] FIG. 11 is a front view showing a valve timing change device according to a third embodiment of the present invention, illustrating the relationship between the rotational bias spring, the second one-end engaging portion of the housing rotor, and the other-end engaging portion of the annular spacer when the rotational bias spring is assembled in the second specification in which the rotational bias spring exerts a rotational bias force in the other direction (CCW direction). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. As the valve timing change device according to the first embodiment of the present invention, a valve timing change device M1 corresponding to a first specification in which the camshaft 1 rotates in one direction (CW direction) and a valve timing change device M2 corresponding to a second specification in which the camshaft 1 rotates in the other direction (CCW direction) are shown.

[0021] The valve timing change device M1 of the first specification is mounted on the camshaft 1 of an internal combustion engine as shown in FIG. 1, and includes a vane rotor 10, a housing rotor 20, an annular spacer 30, a locking mechanism 40 that locks the vane rotor 10 to the housing rotor 20, and a rotational biasing spring 50 as shown in FIGS. 2 to 4.

[0022] Here, the housing rotor 20 corresponds to a first rotor that can rotate around the axis S of the camshaft 1, and the vane rotor 10 and the annular spacer 30 correspond to a second rotor that can rotate relatively within a predetermined angular range with respect to the first rotor and rotates integrally with the camshaft 1. In addition, the rotational bias spring 50 rotates the vane rotor 10 around the axis S relative to the housing rotor 20, and in the first specification shown in Figure 1, it is assembled so as to exert a rotational bias force in one direction (CW direction) around the axis S.

[0023] The camshaft 1 is rotatably supported about an axis S by bearings formed in the cylinder head of the internal combustion engine, and drives the intake valve or the exhaust valve to open and close by a cam action. As shown in Fig. 1, the camshaft 1 has a circular shaft portion 1a that rotatably supports a housing rotor 20, passages 1b and 1c for supplying and discharging hydraulic oil, a female screw hole 1d into which a bolt B is screwed, and a fitting hole 1e into which a positioning pin P1 is fitted.

[0024] With the vane rotor 10 and the annular spacer 30 fixed to the camshaft 1 using bolts B, the valve timing changing device M1 transmits the rotational driving force of the crankshaft to the camshaft 1 via the vane rotor 10 by linking the housing rotor 20 with the rotation of the crankshaft via an interlocking member such as a chain or gears. Also, by being connected to a hydraulic control system 2 that controls the flow of hydraulic oil, the valve timing changing device M1 fulfills the function of changing the valve timing in the internal combustion engine. As shown in FIG. 1, the hydraulic control system 2 is composed of a hydraulic control valve 2a that controls the flow of hydraulic oil discharged from the pump, a passage 2b that connects the hydraulic control valve 2a to the passage 1b, a passage 2c that connects the hydraulic control valve 2a to the passage 1c, and a control means (not shown) that controls the operation of the hydraulic control valve 2a. Here, in the valve timing varying device M1, the side where the bolt B is inserted is referred to as the "front side", and the side where the camshaft 1 is connected is referred to as the "rear side".

[0025] The vane rotor 10 is formed using an aluminum material or the like, and as shown in Figures 3 and 4, has a front surface 10a and a rear surface 10b, four vane portions 11, a cylindrical hub portion 12, a through hole 13, a recess 13a, a fitting hole 13b for fitting a positioning pin P2, a mounting hole 14 for attaching a locking mechanism 40, passages 15 and 16, a fitting recess 17 for fitting the camshaft 1, four seals 18 formed at the tip of the vane portion 11, and a positioning hole 19 for fitting the positioning pin P1 of the camshaft 1.

[0026] The four vane portions 11 are disposed at approximately equal intervals with respect to the hub portion 12. Each vane portion 11 is formed with an attachment hole 14 for attaching a lock mechanism 40 thereto. The through hole 13 passes through from the front surface 10a to the rear surface 10b with the axis S as its center so as to define a passage for hydraulic oil around the neck portion by passing the threaded portion and the neck portion of the bolt B without contacting the threaded portion and the neck portion. The recess 13a is formed in a cylindrical shape recessed from the front surface 10a in the direction of the axis S with the axis S as the center so that the annular spacer 30 can be joined by press-fitting. The fitting hole 13b is formed in the bottom surface of the recess 13a so as to extend in the direction of the axis S, so that the positioning pin P2 can be fitted therein.

[0027] As shown in Figures 4 and 5, the mounting hole 14 is opened on the rear surface 10b and is formed to fit the cylindrical holder 41 of the lock mechanism 40. The mounting hole 14 is also formed to communicate with passages 14a, 14b for adjusting pressure. The passage 14a is formed in a long groove 14a formed on the front surface 10a so as to communicate with the outside through the opening 21d. 1 Passage 14b opens to a side surface of one of vane portions 11, communicates with first hydraulic oil chamber C1, and supplies hydraulic oil within first hydraulic oil chamber C1 that acts in a direction to sink lock pin 42.

[0028] 3, 4 and 10, the passage 15 is formed by two groove-like passages 15a formed in the bottom surface of the fitting recess 17 and communicating with the passage 1c of the camshaft 1, and four passages 15b opening on the outer circumferential surface of the hub portion 12. The passage 15 supplies hydraulic oil to the first hydraulic oil chamber C1 and discharges hydraulic oil from the first hydraulic oil chamber C1 via a passage defined around the neck portion of the bolt B in the through hole 13. 3, 4 and 11, the passage 16 is formed by four passages 16a that open into the bottom surface of the fitting recess 17 and extend in the direction of the axis S so as to communicate with the passage 1b of the camshaft 1, and four passages 16b that open into the outer circumferential surface of the hub portion 12. The passages 16 supply hydraulic oil to the second hydraulic oil chamber C2 and discharge hydraulic oil from the second hydraulic oil chamber C2. The fitting recess 17 is formed on the rear surface 10b side of the vane rotor 10 as a cylindrical recess into which the front end portion of the shaft portion 1a of the camshaft 1 is fitted.

[0029] The vane rotor 10 is accommodated in the accommodation chamber C of the housing rotor 20 so as to be relatively rotatable within a predetermined angle range, i.e., within the range of angle Δθ between the most retarded position shown in FIG. 10 and the most advanced position shown in FIG. 11, and divides the accommodation chamber C into a first hydraulic oil chamber C1 and a second hydraulic oil chamber C2. The vane rotor 10 is fixed to the camshaft 1 by bolts B via annular spacer 30 and rotates integrally with the camshaft 1.

[0030] As shown in Figs. 3 to 5, the housing rotor 20 has a two-piece structure including a cylindrical front housing 21 with a bottom and a disk-shaped rear housing 22 joined to the front housing 21 by a screw b. The housing rotor 20 accommodates the vane rotor 10 so as to be relatively rotatable within a predetermined angular range (Δθ).

[0031] The front housing 21 is made of aluminum material and is formed into a cylindrical shape with a bottom that defines the accommodation chamber C. The front housing 21 includes a front wall 21a as an outer wall, a one end locking portion 21b provided on the front wall 21a, a cylindrical wall 21c, an opening 21d, four screw holes 21e into which screws b are screwed, and four shoe portions 21f.

[0032] The one-end locking portion 21b is a cylindrical pin with a flange that is fitted into a fitting hole formed in the front wall 21a in the area corresponding to one of the shoe portions 21f, and locks one end 51 of the rotational biasing spring 50. The one-end locking portion 21b serves both to lock the one end 51 in a first specification in which the rotational biasing spring 50 exerts a rotational biasing force in one direction (CW direction) about the axis S, and to lock the one end 51 in a second specification in which the rotational biasing spring 50 exerts a rotational biasing force in the other direction (CCW direction) about the axis S.

[0033] The opening 21d is formed in a circular shape centered on the axis S so that the annular spacer 30 can pass therethrough with a gap. The four shoe portions 21f protrude from the cylindrical wall toward the center (axis S) and are arranged at equal intervals in the circumferential direction.

[0034] The rear housing 22 is formed in a disk shape as a sintered body using an iron-based metal material, and is provided with a tooth row 22a, a mating inner circumferential surface 22b, four circular holes 22c for passing screws b, an inner wall surface 22d, a groove-like passage 22e, and a mating hole 22f.

[0035] The tooth row 22a is formed so as to mesh with an interlocking member that is interlocked with the rotation of the crankshaft. The fitting inner peripheral surface 22b is rotatably fitted to the shaft portion 1a of the camshaft 1. The inner wall surface 22d forms a plane perpendicular to the axis S, and is in slidable contact with the rear surface 10b of the vane rotor 10 in the direction of the axis S. The passage 22e is formed in the inner wall surface 22d in a groove shape and in communication with the passage 16 (passage 16b) in order to supply and discharge the hydraulic oil to and from the fitting hole 22f. The fitting hole 22f is formed in the inner wall surface 22d so that the lock pin 42 included in the lock mechanism 40 can be fitted therein.

[0036] The annular spacer 30 is formed as a sintered body of an iron-based material, and as shown in Figures 5 to 8, has a cylindrical portion 31 centered on the axis S, a bottom wall portion 32, a circular hole 33 for passing a bolt B, a notch 34 formed in the cylindrical portion 31, and a positioning portion 35 formed in the bottom wall portion 32.

[0037] The cylindrical portion 31 is passed through the opening 21d of the front housing 21 with a gap therebetween, and is press-fitted into the recess 13a of the vane rotor 10. The bottom wall portion 32 is joined to the bottom surface of the recess 13a of the vane rotor 10 and is formed so that the head of the bolt B comes into contact with it from the outside. The circular hole 33 is formed with an inner diameter dimension that allows the bolt B to be passed through.

[0038] The notch portion 34 is formed by cutting out a part of the cylindrical portion 31 in the direction of the axis S. The notch portion 34 defines a first other-end locking portion 34a at one side edge of the notch portion 34 in the circumferential direction and a second other-end locking portion 34b at the other side edge of the notch portion 34 in the circumferential direction as a plurality of locking portions that selectively lock the other end 52 of the rotation biasing spring 50. The first other end locking portion 34a is a first locking portion that locks the other end 52 in the first specification in which the rotation biasing spring 50 exerts a rotation biasing force in one direction about the axis S (CW direction). The second other end locking portion 34b is a second locking portion that locks the other end 52 in the second specification in which the rotation biasing spring 50 exerts a rotation biasing force in the other direction about the axis S (CCW direction). Here, the first other end locking portion 34a is used to lock the other end 52 of the rotation biasing spring 50 in the first specification.

[0039] The positioning portion 35 positions the annular spacer 30 relative to the vane rotor 10 around the axis S, and is formed as a slightly radially long hole into which the positioning pin P2 fitted in the vane rotor 10 is fitted. The positioning portion 35 includes a first positioning portion 35a and a second positioning portion 35b into which the positioning pin P2 is selectively fitted, at positions spaced a predetermined angle α apart about the axis S. The angle α is set in consideration of the angle Δθ and the width dimension of the cutout portion 34 (an included angle between one side edge and the other side edge of the cutout portion 34, with the axis S as the center). In the first specification in which the rotation biasing spring 50 exerts a rotation biasing force in one direction about the axis S (CW direction), the positioning pin P2 is fitted into the first positioning portion 35a. In the second specification in which the rotation biasing spring 50 exerts a rotation biasing force in the other direction about the axis S (CCW direction), the positioning pin P2 is fitted into the second positioning portion 35b. Here, the first positioning portion 35a is used for positioning the annular spacer 30 relative to the vane rotor 10 in the first specification.

[0040] As shown in FIG. 5, the lock mechanism 40 includes a cylindrical holder 41, a lock pin 42, and a coil spring 43. The cylindrical holder 41 is fitted into the mounting hole 14 of the vane rotor 10 so as to hold the lock pin 42 biased by the coil spring 43 so as to be capable of reciprocating motion. The lock pin 42 is freely movable back and forth in the direction of the axis S, and protrudes from the rear surface 10b of the vane rotor 10 due to the biasing force of the coil spring 43 to fit into a fitting hole 22f of the rear housing 22. The lock pin 42 is also configured to be embedded in the vane rotor 10 when it receives the hydraulic pressure of the hydraulic oil guided to the fitting hole 22f or the hydraulic pressure of the hydraulic oil guided through the passage 14b. The coil spring 43 exerts a biasing force in a direction that causes the lock pin 42 to protrude from the rear surface 10b of the vane rotor 10.

[0041] In the lock mechanism 40 configured as described above, when the oil pressure of the hydraulic oil supplied through passages 16 and 22e drops and the oil pressure of the hydraulic oil supplied through passage 14b drops, the lock pin 42 fits into the fitting hole 22f of the housing rotor 20 by the biasing force of the coil spring 43, and the vane rotor 10 is locked in the most retarded position relative to the housing rotor 20. On the other hand, when the hydraulic pressure of the hydraulic oil guided through the passages 16 and 22e becomes greater than the biasing force of the coil spring 43, the lock pin 42 retracts from the rear surface 10b of the vane rotor 10, unlocking the vane rotor 10. When the hydraulic pressure of the hydraulic oil supplied through the passage 14b becomes greater than the biasing force of the coil spring 43, the unlocked state is maintained.

[0042] The rotational biasing spring 50 is formed in advance into a spiral shape using a flat material such as spring steel, and is a spiral spring having one end 51 located at the outer circumferential end and the other end 52 at the inner circumferential end, as shown in Figures 1 to 4. In the first specification, the rotational biasing spring 50 is arranged along the front wall 21a, with one end 51 engaged with one end locking portion 21b provided on the front wall 21a serving as the outer wall, and the other end 52 engaged with the first other end locking portion 34a of the annular spacer 30. That is, the rotation biasing spring 50 is assembled with a set load that exerts a predetermined rotation biasing force that rotates the vane rotor 10 in one direction (CW direction) about the axis S, that is, in the advance angle direction, relative to the housing rotor 20.

[0043] In this way, by employing the rotational biasing spring 50 that biases in the advance angle direction, it is possible to prevent rattling of the vane rotor 10, reduce the hydraulic pressure required for advancing the angle, and improve responsiveness. Furthermore, by setting the set load of the rotation biasing spring 50 so that the difference between the operating torque and the load torque is approximately equal during the advance angle and the retard angle, controllability can be improved. In particular, since the rotation biasing spring 50 is a spiral spring, the dimension in the direction of the axis S is the thickness dimension of the wire diameter only, and therefore it is possible to achieve a reduction in thickness and size of the device in the direction of the axis S.

[0044] Next, a method of assembling the variable valve timing device M1 will be described. The vane rotor 10, the positioning pin P2, the four seals 18, the front housing 21, the rear housing 22, the annular spacer 30, the lock mechanism 40, the rotation biasing spring 50, and the four screws b are prepared in advance. First, the positioning pin P2 is fitted into the fitting hole 13b of the vane rotor 10 and fixed. Next, the cylindrical portion 31 is press-fitted into the recess 13a while the positioning pin P2 is fitted into the first positioning portion 35a, thereby fixing the annular spacer 30 to the vane rotor 10. Next, the lock mechanism 40 is attached to the attachment hole 14 of the vane rotor 10 .

[0045] Next, the vane rotor 10 is inserted into the accommodation chamber C of the front housing 21 so that the front end region of the annular spacer 30 protrudes from the opening 21d. Also, the four seals 18 are inserted into the seal grooves of the vane rotor 10. Next, the rear housing 22 is joined to the front housing 21 so as to face each other and cover the rear surface 10b of the vane rotor 10, the lock pin 42 is fitted into the fitting hole 22f, and the four screws b are passed through the circular holes 22c and screwed into the screw holes 21e, thereby joining the rear housing 22 to the front housing 21.

[0046] Next, the rotational biasing spring 50 is positioned along the front wall 21a of the housing rotor 20, one end 51 is engaged with the one end engaging portion 21b provided on the front wall 21a, and the other end 52 is engaged with the first other end engaging portion 34a of the annular spacer 30 protruding from the opening 21d. At this time, as shown in FIG. 9, the angle formed by one end 51 and the other end 52 of the rotation biasing spring 50 is θs, and the rotation biasing spring 50 is assembled with a set load that exerts a predetermined rotation biasing force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 10 and annular spacer 30) relative to the first rotor (housing rotor 20) in one direction (CW direction) about the axis S, that is, in the advance angle direction. This completes the assembly of the variable valve timing device M1. Note that the assembly procedure is not limited to the above, and other procedures may be used.

[0047] In this manner, the valve timing change device M1 can be easily assembled by the simple steps of inserting the vane rotor 10 and the annular spacer 30 into the cylindrical front housing 21 with a bottom, covering it with the rear housing 22, joining the front housing 21 and the rear housing 22 with screws b, and positioning and attaching the rotational biasing spring 50 from the outside of the housing rotor 20.

[0048] Next, the operation of the valve timing varying device M1 will be described with reference to FIGS. When the internal combustion engine is stopped, the hydraulic oil in the first hydraulic oil chamber C1 and the second hydraulic oil chamber C2 is discharged, and the vane rotor 10 is positioned at the most retarded angle position as shown in Fig. 10. In addition, the lock pin 42 of the lock mechanism 40 is fitted into the fitting hole 22f, and the vane rotor 10 is locked with respect to the housing rotor 20. As a result, when starting the internal combustion engine, flapping of the vane rotor 10 can be prevented, and the internal combustion engine can be started smoothly.

[0049] Next, when the internal combustion engine starts, hydraulic oil is supplied to the tip of the lock pin 42 through the passage 16 and the passage 22e, and the lock pin 42 is pressed and disengaged from the fitting hole 22f, thereby releasing the locked state. After the internal combustion engine starts, the hydraulic control valve 2a is appropriately switched, and phase control is performed so that the vane rotor 10 and the camshaft 1 are advanced or retarded or are held at a predetermined angle position.

[0050] For example, in the advance mode, the hydraulic oil in the first hydraulic oil chamber C1 is discharged through the passage 15 and the passage 2c, and the hydraulic oil is supplied to the second hydraulic oil chamber C2 through the passage 2b and the passage 16. Then, the vane rotor 10 rotates clockwise, i.e., toward the advance side, relative to the housing rotor 20, due to the hydraulic pressure of the hydraulic oil in the second hydraulic oil chamber C2, and can rotate to the most advance position shown in FIG.

[0051] On the other hand, in the case of the retard mode, the hydraulic oil in the second hydraulic oil chamber C2 is discharged through the passage 16 and the passage 2b, and the hydraulic oil is supplied to the first hydraulic oil chamber C1 through the passage 2c and the passage 15. Then, the vane rotor 10 rotates counterclockwise relative to the housing rotor 20, i.e., to the retard side, due to the hydraulic pressure of the hydraulic oil in the first hydraulic oil chamber C1. As shown in FIG. 10, when the vane rotor 10 moves to the most retarded position, the lock pin 42 faces the fitting hole 22f. However, since the hydraulic oil in the first hydraulic oil chamber C1 acts through the passage 14b in a direction to sink the lock pin 42, the lock pin 42 does not engage with the fitting hole 22f and the unlocked state is maintained.

[0052] In addition, in the case of a holding mode in which the vane rotor 10 is held at an intermediate position between the most advanced position and the most retarded position, the hydraulic control valve 2a is switched to supply hydraulic oil to the first hydraulic oil chamber C1 and the second hydraulic oil chamber C2, and the vane rotor 10 is held at a predetermined intermediate position by the hydraulic pressure of the hydraulic oil in the first hydraulic oil chamber C1 and the second hydraulic oil chamber C2. As described above, in the first specification, the first hydraulic oil chamber C1 functions as a retard chamber that generates oil pressure to rotate the vane rotor 10 to the retard side relative to the housing rotor 20, and the second hydraulic oil chamber C2 functions as an advance chamber that generates oil pressure to rotate the vane rotor 10 to the advance side relative to the housing rotor 20.

[0053] The valve timing change device M2 of the second specification is mounted on the camshaft 1 of an internal combustion engine as shown in FIG. 12, and includes a vane rotor 110, a housing rotor 120 consisting of a front housing 21 and a rear housing 122, an annular spacer 30, a locking mechanism 40 that locks the vane rotor 110 to the housing rotor 120, and a rotational biasing spring 50 as shown in FIGS. 13 to 15.

[0054] Incidentally, the valve timing changing device M2 is assembled with respect to the valve timing changing device M1 so that the rotation direction of the camshaft 1 changes from the CW direction to the CCW direction, and the rotation biasing spring 50 rotationally biases the vane rotor 110 in the other direction (CCW direction) relative to the housing rotor 120. Also, the most retarded position of the device M1 corresponds to the most advanced position of the device M2, and the most advanced position of the device M1 corresponds to the most advanced position of the device M2, and the angle by which the vane rotor 110 can rotate relative to the housing rotor 120 is the same angle Δθ. Here, the housing rotor 120 corresponds to a first rotor that can rotate around the axis S of the camshaft 1, and the vane rotor 110 and the annular spacer 30 correspond to a second rotor that can rotate relatively within a predetermined angular range (Δθ) with respect to the first rotor and rotates integrally with the camshaft 1.

[0055] The vane rotor 110 has the same configuration as the vane rotor 10 except that the passages 14b of the vane rotor 10 described above are changed to passages 114b. Therefore, the same components are denoted by the same reference numerals and description thereof will be omitted. The passage 114b opens to a side surface of one of the vane portions 11 and communicates with the second hydraulic oil chamber C2, and supplies hydraulic oil in the second hydraulic oil chamber C2 that acts in a direction to sink the lock pin .

[0056] The rear housing 122 of the housing rotor 120 has the same configuration as the rear housing 22 except that the passage 22e and mating hole 22f in the rear housing 22 of the housing rotor 20 are changed to passage 122e and mating hole 122f. Therefore, the same components are given the same symbols and their descriptions are omitted. The passage 122e is formed in the inner wall surface 22d in a groove shape and in communication with the passage 15 (passage 15b) in order to supply and discharge the hydraulic oil to and from the fitting hole 122f. The fitting hole 122f is formed in the inner wall surface 22d so that the lock pin 42 included in the lock mechanism 40 can be fitted therein.

[0057] Next, a method of assembling the variable valve timing device M2 will be described. The vane rotor 110, the positioning pin P2, the four seals 18, the front housing 21, the rear housing 122, the annular spacer 30, the lock mechanism 40, the rotation biasing spring 50, and the four screws b are prepared in advance. First, the positioning pin P2 is fitted into the fitting hole 13b of the vane rotor 110 and fixed. Subsequently, the cylindrical portion 31 is press-fitted into the recess 13a while the positioning pin P2 is fitted into the second positioning portion 35b, thereby fixing the annular spacer 30 to the vane rotor 10. Next, the lock mechanism 40 is attached to the attachment hole 14 of the vane rotor 10 .

[0058] Next, the vane rotor 110 is inserted into the accommodation chamber C of the front housing 21 so that the front end region of the annular spacer 30 protrudes from the opening 21d. In addition, the four seals 18 are inserted into the seal grooves of the vane rotor 110. Next, the rear housing 122 is joined to the front housing 21 so as to face each other and cover the rear surface 10b of the vane rotor 110, the lock pin 42 is fitted into the fitting hole 122f, and the four screws b are passed through the circular holes 22c and screwed into the screw holes 21e, thereby joining the rear housing 122 to the front housing 21.

[0059] Next, the rotational biasing spring 50 is placed along the front wall 21a of the housing rotor 20 in the opposite direction to the first specification, i.e., upside down, and one end 51 is engaged with the one-end locking portion 21b provided on the front wall 21a, and the other end 52 is engaged with the second other-end locking portion 34b of the annular spacer 30 protruding from the opening 21d. At this time, as shown in FIG. 16, the angle θs between one end 51 and the other end 52 of the rotational bias spring 50 is the same as the angle θs in the first specification, that is, the rotational bias spring 50 is assembled with a set load that exerts the same rotational bias force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 10 and annular spacer 30) relative to the first rotor (housing rotor 20) in the other direction (CCW direction) about the axis S, that is, in the advance angle direction. This completes the assembly of the variable valve timing device M2. Note that the assembly procedure is not limited to the above, and other procedures may be used.

[0060] In this manner, the valve timing change device M2 can be easily assembled by the simple steps of inserting the vane rotor 110 and the annular spacer 30 into the cylindrical front housing 21 with a bottom, covering it with the rear housing 122, joining the front housing 21 and the rear housing 122 with screws b, and positioning and attaching the rotational biasing spring 50 from the outside of the housing rotor 120.

[0061] In the variable valve timing device M2, the first hydraulic oil chamber C1 functions as an advance chamber, and the second hydraulic oil chamber C2 functions as a retard chamber, and the roles of the passage 15 and the passage 16 are interchanged. That is, the variable valve timing device M2 operates in the same manner as the previously described variable valve timing device M1, except that the passages 15 and 16 and the first hydraulic oil chamber C1 and the second hydraulic oil chamber C2 are interchanged for retard operation and advance operation, and therefore a description thereof will be omitted here.

[0062] As described above, in the valve timing change devices M1, M2 in which the rotational directions of the camshaft 1 are different, by providing the first other-end locking portion 34a and the second other-end locking portion 34b as multiple locking portions (first locking portion and second locking portion) that selectively lock the other end 52 of the rotational biasing spring 50 to the annular spacer 30 that constitutes the second rotor, it is possible to assemble the rotational biasing spring 50 of the same specifications to the devices M1, M2. In this way, the same rotational biasing spring 50 can be attached to the devices M1 and M2 of different specifications, so it is possible to share not only the rotational biasing spring 50 but also most other parts. Therefore, it is possible to share parts and reduce the cost of the device.

[0063] In particular, the annular spacer 30 has a first other end locking portion 34a and a second other end locking portion 34b as a plurality of selectively used locking portions, as well as a first positioning portion 35a and a second positioning portion 35b that are selectively used. Therefore, when the rotational biasing spring 50 is assembled so that the set load is the same in the first and second specifications, that is, so that the engagement angle θs between one end 51 and the other end 52 is the same, as shown in Figures 9 and 16, by selectively using the first positioning portion 35a or the second positioning portion 35b to cover the adjustment allowance, it is possible to provide multiple engagement portions (first engagement portion and second engagement portion) without increasing the width dimension of one cutout portion 34, that is, without reducing the mechanical strength, and a robust annular spacer 30 can be provided.

[0064] Figures 17 and 18 show a second embodiment of the present invention, which is the same as the first embodiment except that an annular spacer 130 is used instead of the annular spacer 30 of the first embodiment. The same symbols are used for the same configurations as in the first embodiment, and descriptions thereof will be omitted. In the second embodiment, the annular spacer 130 is formed as a sintered body of an iron-based material, and includes a cylindrical portion 31 centered on the axis S, a bottom wall portion 32, a circular hole 33 for passing a bolt B, a first other end locking portion 134a and a second other end locking portion 134b formed on the cylindrical portion 31, and a positioning portion 135 formed on the bottom wall portion 32.

[0065] The first other end locking portion 134a and the second other end locking portion 134b are formed by cutting out the cylindrical portion 31 in the direction of the axis S, and function as a plurality of locking portions that selectively lock the other end 52 of the rotation biasing spring 50. The first other end locking portion 134a is a first locking portion that locks the other end 52 in the first specification in which the rotation biasing spring 50 exerts a rotation biasing force in one direction about the axis S (CW direction). The second other end locking portion 134b is a second locking portion that locks the other end 52 in the second specification in which the rotation biasing spring 50 exerts a rotation biasing force in the other direction about the axis S (CCW direction). The positioning portion 135 positions the annular spacer 30 relative to the vane rotors 10, 110 around the axis S, and is formed as a slightly elongated hole that is radially long so that the positioning pin P2 fitted in the vane rotors 10, 110 can be fitted therein.

[0066] In the second embodiment, the annular spacer 130 is fixed to the vane rotors 10, 110 by fitting the positioning pin P2 into the positioning portion 135 and by press-fitting the cylindrical portion 31 into the recess 13a. In the first specification, as shown in FIG. 17, the rotational biasing spring 50 is arranged along the front wall 21a of the housing rotor 20, with one end 51 engaged with one end locking portion 21b provided on the front wall 21a, and the other end 52 engaged with a first other end locking portion 134a of the annular spacer 130 protruding from the opening 21d. At this time, the rotation biasing spring 50 is assembled with an angle θs between one end 51 and the other end 52, similar to the state shown in FIG. 9, and with a set load that exerts a predetermined rotation biasing force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 10 and annular spacer 130) relative to the first rotor (housing rotor 20) in one direction (CW direction) about the axis S, that is, in the advance angle direction.

[0067] On the other hand, in the second specification, as shown in FIG. 18, the rotational biasing spring 50 is arranged along the front wall 21a of the housing rotor 120 in an inverted orientation relative to the form shown in FIG. 17, with one end 51 engaged with one end locking portion 21b provided on the front wall 21a, and the other end 52 engaged with the second other end locking portion 134b of the annular spacer 130 protruding from the opening 21d. At this time, the rotation biasing spring 50 is assembled with an angle θs between one end 51 and the other end 52, similar to the state shown in FIG. 16, and with a set load that exerts a predetermined rotation biasing force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 110 and annular spacer 130) relative to the first rotor (housing rotor 120) in the other direction (CCW direction) about the axis S, that is, in the advance angle direction.

[0068] In the second embodiment, as described above, in valve timing change devices M1, M2 in which the rotational directions of the camshaft 1 are different, a first other-end locking portion 134a and a second other-end locking portion 134b are provided as a plurality of locking portions (first locking portion and second locking portion) that selectively lock the other end 52 of the rotational biasing spring 50 to the annular spacer 130 that constitutes the second rotor, so that a rotational biasing spring 50 of the same specifications can be assembled to the devices M1, M2. In this way, the same rotational biasing spring 50 can be attached to the devices M1 and M2 of different specifications, so it is possible to share not only the rotational biasing spring 50 but also most other parts. Therefore, it is possible to share parts and reduce the cost of the device.

[0069] Figures 19 and 20 show a third embodiment of the present invention, which is the same as the first embodiment except that housing rotors 220, 320 including an annular spacer 230 and a front housing 221 are adopted instead of the annular spacer 30 and front housing 21 of the first embodiment. The same reference symbols are used for the same configurations as in the first embodiment, and descriptions thereof will be omitted. In the third embodiment, the housing rotor 220 includes a front housing 221 and a rear housing 22, and is applied in a first specification. The housing rotor 320 includes a front housing 221 and a rear housing 122, and is applied in a second specification.

[0070] The front housing 221 is formed using an aluminum material in a cylindrical shape with a bottom that defines the storage chamber C, and is equipped with a front wall 21a as an outer wall, a first one-end locking portion 221a and a second one-end locking portion 221b formed integrally with the front wall 21a, a cylindrical wall 21c, an opening 21d, four screw holes 21e for screwing in screws b, and four shoe portions 21f.

[0071] The first end locking portion 221a and the second end locking portion 221b are each formed as a protrusion that protrudes from the front wall 21a in the direction of the axis S, and selectively lock one end 51 of the rotation biasing spring 50. The first one-end locking portion 221a is a first locking portion that locks the one end 51 in the first specification in which the rotation biasing spring 50 exerts a rotation biasing force in one direction about the axis S (CW direction). The second one-end locking portion 221b is a second locking portion that locks the one end 51 in the second specification in which the rotation biasing spring 50 exerts a rotation biasing force in the other direction about the axis S (CCW direction).

[0072] The annular spacer 230 is formed as a sintered body of an iron-based material, and includes a cylindrical portion 31 centered on the axis S, a bottom wall portion 32, a circular hole 33 for passing a bolt B, an other end locking portion 234 formed in the cylindrical portion 31, and a positioning portion 235 formed in the bottom wall portion 32. The other end locking portion 234 is formed by cutting out the cylindrical portion 31 in the direction of the axis S, and locks the other end 52 of the rotation biasing spring 50 . The other end locking portion 234 serves both to lock the other end 52 in a first specification in which the rotational biasing spring 50 exerts a rotational biasing force in one direction (CW direction) about the axis S, and to lock the other end 52 in a second specification in which the rotational biasing spring 50 exerts a rotational biasing force in the other direction (CCW direction) about the axis S. The positioning portion 235 positions the annular spacer 230 relative to the vane rotors 10, 110 around the axis S, and is formed as a slightly elongated hole that is radially long so that the positioning pin P2 fitted in the vane rotors 10, 110 can be fitted therein.

[0073] In the third embodiment, the annular spacer 230 is fixed to the vane rotors 10, 110 by fitting the positioning pin P2 into the positioning portion 235 and by press-fitting the cylindrical portion 31 into the recess 13a. In the first specification, as shown in FIG. 19, the rotational biasing spring 50 is arranged along the front wall 21a of the housing rotor 220, with one end 51 engaged with a first one-end locking portion 221a provided on the front wall 21a, and the other end 52 engaged with the other-end locking portion 234 of the annular spacer 230 protruding from the opening 21d. At this time, the rotation biasing spring 50 is assembled with an angle θs between one end 51 and the other end 52, similar to the state shown in FIG. 9, and with a set load that exerts a predetermined rotation biasing force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 10 and annular spacer 230) relative to the first rotor (housing rotor 220) in one direction (CW direction) about the axis S, that is, in the advance angle direction.

[0074] On the other hand, in the second specification, as shown in FIG. 20, the rotational biasing spring 50 is arranged along the front wall 21a of the housing rotor 320 in an inverted orientation relative to the form shown in FIG. 19, with one end 51 engaged with the second one-end engaging portion 221b provided on the front wall 21a, and the other end 52 engaged with the other-end engaging portion 234 of the annular spacer 230 protruding from the opening 21d. At this time, the rotation biasing spring 50 is assembled with an angle θs between one end 51 and the other end 52, similar to the state shown in FIG. 16, and with a set load that exerts a predetermined rotation biasing force. In this assembled state, the rotation biasing spring 50 rotationally biases the second rotor (vane rotor 110 and annular spacer 230) relative to the first rotor (housing rotor 320) in the other direction (CCW direction) about the axis S, that is, in the advance angle direction.

[0075] In the third embodiment, as described above, in valve timing change devices M1, M2 in which the rotational directions of the camshaft 1 are different, a first one-end locking portion 221a and a second one-end locking portion 221b are provided as a plurality of locking portions (first locking portion and second locking portion) that selectively lock one end 51 of the rotational biasing spring 50 to the housing rotors 220, 320 that constitute the first rotor, so that a rotational biasing spring 50 of the same specifications can be assembled to the devices M1, M2. In this way, the same rotational biasing spring 50 can be attached to the devices M1 and M2 of different specifications, so it is possible to share not only the rotational biasing spring 50 but also most other parts. Therefore, it is possible to share parts and reduce the cost of the device.

[0076] In the above embodiment, the rotation biasing spring 50 in the form of a spiral spring is shown as the rotation biasing spring, but the present invention is not limited to this, and a torsion coil spring may also be used as the rotation biasing spring. In the above embodiment, a form in which the rotational biasing spring 50 is engaged so as to generate the same set load is shown as a plurality of engaging portions that selectively engage one end or the other end of the rotational biasing spring provided on the first rotor or the second rotor, but this is not limited to this, and in a case in which the set load differs depending on the specifications of the internal combustion engine, two or more engaging portions that can engage the same rotational biasing spring by changing the engaging angle may be adopted as long as the changing of the engaging angle is functionally acceptable.

[0077] In the above embodiment, a configuration is adopted in which the second rotor includes a vane rotor 10, 110 and an annular spacer 30, 130, 230, and one end locking portion 21b is provided on the housing rotor 20, 120, and the first other end locking portion 34a, 134a and the second other end locking portion 34b, 134b are provided on the annular spacer 30, 130. However, this is not limited to this, and the present invention may also be adopted in a configuration in which the second rotor consists of only a vane rotor. In this case, the first rotor may be a housing rotor that defines the accommodating chamber, the second rotor may be a vane rotor that is accommodated in the accommodating chamber, the one end locking portion may be provided on the housing rotor, and the first other end locking portion and the second other end locking portion may be provided on the vane rotor. In addition, the first rotor may be a housing rotor that defines an accommodating chamber, the second rotor may be a vane rotor that is accommodated in the accommodating chamber, the first one-end locking portion and the second one-end locking portion may be provided on the housing rotor, and the other end locking portion may be provided on the vane rotor.

[0078] In the above embodiment, the housing rotor 20, 120, 220, 320 is shown as a two-piece structure consisting of a front housing and a rear housing, but the present invention is not limited to this. For example, the present invention may be adopted in a configuration including a three-piece structure consisting of a flat front housing, a cylindrical outer housing, and a flat rear housing, or a housing rotor of another shape.

[0079] In the above embodiment, the lock mechanism 40 includes the cylindrical holder 41, the lock pin 42, and the coil spring 43 and locks the vane rotor 10, 110 at the most retarded position, but the present invention is not limited to this. For example, other lock mechanisms may be used as long as they are capable of locking the vane rotor 10, 110 to the housing rotor 20, 120, 20, 320, and the lock position is not limited to the most retarded position, but may be the most advanced position or another position as necessary.

[0080] As described above, the valve timing changing device of the present invention can achieve the common use of parts and therefore the cost of the device can be reduced. Therefore, it is not only applicable to internal combustion engines mounted on automobiles, but is also useful in small internal combustion engines mounted on motorcycles, etc., and internal combustion engines mounted on other vehicles or ships, etc. [Explanation of symbols]

[0081] 1 Camshaft S axis CW unidirectional CCW Other direction M1 Valve timing change device for the first specification Valve timing change device for M2 2nd specification 10,110 Vane rotor (second rotor) 20,120 Housing rotor (first rotor) C Containment Room 21a Front wall (outer wall) 21b One end locking part 21c opening 30 Annular spacer (second rotor) 31 Cylindrical section 34 Notch 34a: First other end locking portion (first locking portion) 34b second other end locking portion (second locking portion) 35a First positioning part 35b Second positioning part 50 Rotational spring (spiral spring) 51 One end 52 Other end 130 Annular spacer (second rotor) 134a: First other end locking portion (first locking portion) 134b second other end locking portion (second locking portion) 220,320 Housing rotor (first rotor) 221a First one end locking part (first locking part) 222b Second one end locking part (second locking part) 230 Annular spacer (second rotor) 234 Other end locking part

Claims

1. A valve timing change device that changes the opening and closing timing of an intake valve or an exhaust valve driven by a camshaft, A first rotor rotatable about an axis of the camshaft; a second rotor including a vane rotor accommodated in the first rotor and a bottomed cylindrical annular spacer joined to the vane rotor and positioned thereon, the second rotor being rotatable within a predetermined angular range relative to the first rotor and rotating integrally with the camshaft; a rotation biasing spring that biases the second rotor relative to the first rotor about the axis; the first rotor includes a one-end locking portion that locks one end of the rotation biasing spring, the annular spacer includes a first other end locking portion that locks the other end of the rotational biasing spring to correspond to a first specification in which the rotational biasing spring exerts a rotational biasing force in one direction about the axis, a second other end locking portion that locks the other end of the rotational biasing spring to correspond to a second specification in which the rotational biasing spring exerts a rotational biasing force in the other direction about the axis, a first positioning portion that is positioned about the axis with respect to the vane rotor to correspond to the first specification, and a second positioning portion that is positioned about the axis with respect to the vane rotor to correspond to the second specification, the first other end locking portion, the second other end locking portion, the first positioning portion, and the second positioning portion are arranged so as to be assembled with a set load that causes the rotation biasing spring to exert the same rotation biasing force in the first specification and the second specification. A valve timing varying device.

2. the annular spacer includes a notch formed in a cylindrical portion, The notch portion defines the first other-end locking portion at one side edge and defines the second other-end locking portion at the other side edge.

2. The valve timing changing device according to claim 1.

3. The first rotor is a housing rotor defining a housing chamber for accommodating the vane rotor, the housing rotor includes an opening through which the annular spacer projects in the axial direction, and an outer wall defining the opening; the rotation biasing spring is a spiral spring disposed along the outer wall, one end of which is engaged with the one end engaging portion provided on the outer wall, and the other end of which is engaged with the first other end engaging portion or the second other end engaging portion of the annular spacer.

3. The valve timing changing device according to claim 1 or 2.

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