VALVE OPENING AND CLOSING TIMING CONTROL APPARATUS
20170234174 · 2017-08-17
Assignee
Inventors
Cpc classification
F01L2001/34426
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/34466
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/34463
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/356
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/34433
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/3443
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/3442
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/34473
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
A valve opening and closing timing control apparatus includes a driving-side rotating body, a driven-side rotating body fixed to a camshaft by a bolt, a fluid pressure chamber, an intermediate lock mechanism, a lock flow passage bringing the working fluid to the intermediate lock mechanism, and an electromagnetic valve including a spool which is arranged at an inner portion of the bolt, the lock flow passage including a first flow passage which is arranged between the spool and a supply flow passage in a radial direction and which is connected to the supply flow passage, the lock flow passage including a second flow passage which is provided at the inner portion of the bolt in a penetrating manner in the radial direction and which brings the working fluid to flow between the spool and the intermediate lock mechanism.
Claims
1. A valve opening and closing timing control apparatus comprising: a driving-side rotating body rotating synchronously with a crankshaft of an internal combustion engine; a driven-side rotating body arranged coaxially with an axis of the driving-side rotating body and rotating integrally with a camshaft for opening and closing valves of the internal combustion engine in a state being fixed to the camshaft by a bolt; a fluid pressure chamber defined between the driving-side rotating body and the driven-side rotating body; an intermediate lock mechanism selectively switchable between a locked state in which a relative rotational phase of the driven-side rotating body relative to the driving-side rotating body is locked at an intermediate lock phase between a most advanced angle phase and a most retarded angle phase and an unlocked state in which the locked state is released; a lock flow passage bringing a working fluid to the intermediate lock mechanism; and an electromagnetic valve including a spool which is arranged at an inner portion of the bolt and controlling supply and discharge of the working fluid relative to the fluid pressure chamber and the intermediate lock mechanism, the lock flow passage including a first flow passage which is arranged between the spool and a supply flow passage in a radial direction and which is connected to the supply flow passage, the supply flow passage bringing the working fluid supplied from a pump to flow along the axis direction at the inner portion of the bolt, the lock flow passage including a second flow passage which is provided at the inner portion of the bolt in a penetrating manner in the radial direction and which brings the working fluid to flow between the spool and the intermediate lock mechanism, at least a portion of the first flow passage and at least a portion of the second flow passage being positioned within a same plane orthogonal to the axis.
2. The valve opening and closing timing control apparatus according to claim 1, wherein the bolt is constituted by a first member screwed on the camshaft and a second member arranged along an outer surface of the first member, the supply flow passage is defined between the first member and the second member, the first flow passage is defined at the first member.
3. The valve opening and closing timing control apparatus according to claim 2, wherein the second member is press-fitted to the first member along the axis direction.
4. The valve opening and closing timing control apparatus according to claim 3, wherein at least an end portion of the second member at an opposite side from the camshaft in the axis direction is press-fitted to the first member, the first flow passage and the second flow passage are arranged at the opposite side from the camshaft in the axis direction relative to a flow passage which supplies and discharges the working fluid to and from the fluid pressure chamber.
5. The valve opening and closing timing control apparatus according to claim 4, wherein only a portion of the second member at the opposite side from the camshaft in the axis direction relative to the flow passage which supplies and discharges the working fluid to and from the fluid pressure chamber is fitted to the first member.
6. The valve opening and closing timing control apparatus according to claim 2, wherein a fixing member which blocks a movement of the second member relative to the first member in a circumferential direction is provided over the first member and the second member.
Description
BRIEF DESCRIPTION OF DRAWINGS
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MODE FOR CARRYING OUT THE INVENTION
[0037] Embodiments of a valve opening and closing timing control apparatus according to the present invention are explained with reference to the attached drawings. A first embodiment is explained as an embodiment where a valve opening and closing timing control apparatus 10 is employed at intake valves 103 of an internal combustion engine (which is hereinafter referred to as an “engine E”). The valve opening and closing timing control apparatus, however, is not limited to the following embodiments and may be variously modified within a scope of the invention.
Entire Construction
[0038] As illustrated in
[0039] An external threaded portion 5b is provided at an end portion of the bolt B at a side close to the camshaft 101. In a state where the housing 1 and the inner rotor 2 are assembled on each other, the bolt B is inserted to a center of the assembly of the housing 1 and the inner rotor 2 so that the external threaded portion 5b of the bolt B is screwed on an internal threaded portion 101a of the camshaft 101. As a result, the bolt B is fixed to the camshaft 101, and the inner rotor 2 and the camshaft 101 are also fixed to each other.
[0040] As illustrated in
[0041] As illustrated in
[0042] Because the second member 6 is press-fitted to the first member 5, the members 5 and 6 are firmly fixed to each other to inhibit a positioning error between the members 5 and 6 caused by the rotation of the inner rotor 2. In the present embodiment, the entire area of the inner surface of the second member 6 along the axis X direction is press-fitted to the first member 5. Alternatively, a portion of the inner surface of the second member 6 along the axis X direction may be press-fitted to the first member 5.
[0043] As illustrated in
[0044] A return spring 70 is provided between the housing 1 and the camshaft 101 for applying a biasing force in a rotation direction about the axis X. The return spring 70 applies the biasing force until a relative rotational phase of the inner rotor 2 relative to the housing 1 (which is hereinafter also simply referred to as a “relative rotational phase”) reaches a predetermined relative rotational phase at an advanced angle side from a state where the relative rotational phase is at a most retarded angle. The return spring 70 may be disposed between the housing 1 and the inner rotor 2.
[0045] In a case where the crankshaft C is driven to rotate, a rotation drive force of the crankshaft C is transmitted to the timing sprocket 15 via a power transmission member 102 so that the housing 1 is driven to rotate in a rotation direction S illustrated in
[0046] As illustrated in
[0047] Oil is supplied to or discharged from the advanced angle chambers 41 and the retarded angle chambers 42 or supply and discharge of the oil is interrupted so as to change the relative rotational phase to an advanced angle direction or to a retarded angle direction, or to maintain the relative rotational phase at an arbitral phase. The advanced angle direction corresponds to a direction in which a volume of the advanced angle chambers 41 increases as indicated by an arrow S1 in
[0048] As illustrated in
Intermediate Lock Mechanism
[0049] The valve opening and closing timing control apparatus 10 of the present embodiment includes the intermediate lock mechanisms 8 which lock the relative rotational phase at an intermediate lock phase L between the most advanced angle phase and the most retarded angle phase. The relative rotational phase is locked at the intermediate lock phase L under the condition that an oil pressure is not stable immediately after the engine start so that the stable rotation of the engine E may be realized.
[0050] As illustrated in
[0051] Each of the lock members 81 and 83 is constituted by a plate-formed member and is movably supported at the outer rotor 12 so as to come close to or separate from the inner rotor 2 in a state being positioned orthogonal to the axis X. Each of the lock members 81 and 83 may be configured to come close to or separate from the front plate 11 or the rear plate 13 in a state being positioned parallel to the axis X. In addition, the number of the intermediate lock mechanisms 8 is not limited to two and may be one or more than three.
[0052] Each of the recess portions 85 and 86 is formed in a manner that a shallow groove and a deep groove are connected to each other in the circumferential direction. As illustrated in
[0053] The lock flow passages 45 are connected to respective bottom surfaces of the deep grooves of the first recess portion 85 and the second recess portion 86. In a case where the oil is supplied to the recess portions 85 and 86 through the lock flow passages 45 in a case of the locked state, each of the lock members 81 and 83 receives a pressure of the oil. In a case where the oil pressure exceeds the biasing force of each of the springs 82 and 84, the lock members 81 and 83 separate from the recess portions 85 and 86, which results in an unlocked state.
[0054] The lock discharge flow passages 46 are also connected to the respective bottom surfaces of the deep grooves of the recess portions 85 and 86. The lock discharge flow passages 46 are not the flow passages for supplying the oil to the intermediate lock mechanisms 8 but are the flow passages for discharging the oil to the outside.
Electromagnetic Valve
[0055] As illustrated in
[0056] The spool 52 is housed at a housing void 5a which is provided at the inner portion of the bolt B and which serves as a circular bore in a cross-section. The spool 52 is slidable along the axis X direction within the housing void 5a. The spool 52 includes a main discharge flow passage 52b serving as a hole with a bottom in a circular cross-section and extending along the axis X direction.
[0057] In a case where the electromagnetic solenoid 54 is powered, a push pin 54a provided at the electromagnetic solenoid 54 presses an end portion 52a of the spool 52. As a result, the spool 52 slidably moves towards the camshaft 101 against a biasing force of the first spring 53a. The OCV 51 is configured to adjust a position of the spool 52 by changing an amount of power supply to the electromagnetic solenoid 54 from zero to maximum. The amount of power supply to the electromagnetic solenoid 54 is controlled by an ECU (electronic control unit) not illustrated.
[0058] The OCV 51 switches between supply, discharge and retention of the oil relative to the advanced angle chambers 41 and the retarded angle chambers 42 depending on the position of the spool 52 and switches between supply and discharge of the oil to the intermediate lock mechanisms 8.
Construction of Oil Passage
[0059] As illustrated in
[0060] As illustrated in
[0061] A first annular groove 52c for supplying the oil which flows through the supply flow passages 61 to the lock flow passages 45 and a second annular groove 52d for supplying the oil to the advanced angle flow passages 43 or the retarded angle flow passages 44 are provided at the spool 52. In addition, a first penetration passage 52e for discharging the oil that flows through the advanced angle flow passages 43 to the main discharge flow passage 52b and a second penetration passage 52f for discharging the oil that flows through the retarded angle flow passages 44 or the lock discharge flow passages 46 to the main discharge flow passage 52b are provided at the spool 52. Further, a third penetration passage 52g for discharging the oil that flows through the main discharge flow passage 52b to the outside of the valve opening and closing timing control apparatus 10 is provided at the spool 52.
[0062] Each of the advanced angle flow passages 43 connected to the advanced angle chamber 41 includes a first penetration passage 43a provided by penetrating through the first member 5 and the second member 6 of the bolt B in the radial direction and a second penetration passage 43b connected to the first penetration passage 43a and provided at the inner rotor 2. In the same manner, each of the retarded angle flow passages 44 connected to the retarded angle chamber 42 includes a first penetration passage 44a provided by penetrating through the first member 5 and the second member 6 of the bolt B in the radial direction and a second penetration passage 44b connected to the first penetration passage 44a and provided at the inner rotor 2. In each of the first penetration passages 43a and 44a, an annular groove is provided at a boundary portion relative to the inner rotor 2. The advanced angle flow passage 43 and the retarded angle flow passage 44 shares a common supply penetration passage 5f provided by penetrating through the first member 5 of the bolt B in the radial direction and connected to the supply flow passage 61.
[0063] Each of the lock flow passages 45 connected to the intermediate lock mechanism 8 is arranged between the supply flow passage 61 and the spool 52 in the radial direction. The lock flow passage 45 includes the first flow passage 5g connected to the supply flow passage 61. The first flow passage 5g is defined and provided at the first member 5 of the bolt B. In the present embodiment, the bolt B is constituted by two members so that the supply flow passages 61 or the first flow passages 5g, for example, are easily processed as compared to a case where the bolt B is constituted by a single member at which flow passages are formed. In addition, each of the lock flow passages 45 includes the second flow passage 45a provided by penetrating through the first member 5 and the second member 6 of the bolt B in the radial direction and a third flow passage 45b connected to the second flow passage 45a and provided at the inner rotor 2. That is, the first flow passage 5g serves as a path for bringing the oil which flows from the supply flow passage 61 to flow towards the spool 52 while the second flow passage 45a serves as a path for bringing the oil to flow between the spool 52 and the intermediate lock mechanism 8. In the second flow passage 45a, an annular groove is provided at a boundary portion relative to the inner rotor 2.
[0064] Each of the lock discharge flow passages 46 connected to the intermediate lock mechanism 8 is constituted by a first penetration passage 46a provided by penetrating through the first member 5 and the second member 6 of the bolt B in the radial direction and a second penetration passage 46b connected to the first penetration passage 46a and provided at the inner rotor 2. In the first penetration passage 46a, an annular groove is provided at a boundary portion relative to the inner rotor 2.
[0065] As illustrated in
[0066] The plural first flow passages 5g and the plural second flow passages 45a are provided for securing a flow area so that supply or discharge of the oil relative to the intermediate lock mechanisms 8 may be promptly performed. In addition, because the first flow passages 5g and the second flow passages 45a, each of the first flow passages 5g and each of the second flow passages 45a including different lengths from each other, are alternately arranged at even intervals within the same plane, a rotation balance of the inner rotor 2 may be stabilized.
Operation of OCV
[0067] An operation construction of the OCV 51 in a case where the position of the spool 52 changes between W1, W2, W3, W4 and W5 depending on the amount of power supply to the electromagnetic solenoid 54 is illustrated in
[0068] In a case where the electromagnetic solenoid 54 is powered, the spool 52 moves slightly rightward from the state of W1, as illustrated in
[0069] In a case where the electromagnetic solenoid 54 is further powered, the spool 52 moves slightly rightward from the state of W2, as illustrated in
[0070] In a case where the electromagnetic solenoid 54 is further powered as illustrated in
[0071] In a case where the electromagnetic solenoid 54 is further powered as illustrated in
[0072] In the present embodiment, as illustrated in
[0073] Different embodiments are explained below. The basic construction of each of the different embodiments is the same as the first embodiment and thus a different construction is only explained with reference to the attached drawings. For easy understanding of the drawings, the same names and reference numerals for components as the first embodiment are employed.
Second Embodiment
[0074] As illustrated in
[0075] In the phase retention mode where the supply and discharge of the oil relative to the advanced angle chambers 41 and the retarded angle chambers 42 are interrupted as illustrated in
Third Embodiment
[0076] As illustrated in
[0077] In the third embodiment, a position displacement between the first member 5 and the second member 6 which occurs in conjunction with the rotation of the inner rotor 2 may be inhibited by the pins 63. In addition, the position of the second member 6 relative to the first member 5 in the circumferential direction is determinable by matching positions of bores which are provided at the first member 5 and the second member 6 so that the pins 63 are inserted to be positioned within the respective bores. As a result, an easy assembly is achievable. Further, because the relative rotation between the first member 5 and the second member 6 is inhibited by the pins 63, the second member 6 may be mounted to the first member 5 by intermediate fitting or loose fitting. As compared to a case where the second member 6 is press-fitted to the first member 5, occurrence of a foreign substance along with the sliding contact between the members 5 and 6 may be inhibited.
Other Embodiments
[0078] (1) In the aforementioned embodiment, the bolt B is constituted by the two members, i.e., the first member 5 and the second member 6. Alternatively, the bolt B may be constituted by a single member or more than three members. When the first flow passage 5g of the first member 5 is formed in a state where the bolt B is constituted by the single member, a penetration bore is formed at the bolt B in the radial direction and thereafter a cover member is fitted to the penetration bore, for example, so that the first flow passage 5g serving as a blind passage may be obtained. [0079] (2) A thermal expansion rate of metal constituting the first member 5, for example, may be greater than a thermal expansion rate of metal constituting the second member 6, for example. In this case, the members 5 and 6 may be specified to dimensional configurations so that a foreign substance is unlikely to be generated upon press-fitting of the members 5 and 6. In addition, because the first member 5 is more expanded than the second member 6 with temperature increase caused by the operation of the engine E, fitting degree of the members 5 and 6 may improve. [0080] (3) In the aforementioned embodiments, as illustrated in
INDUSTRIAL APPLICABILITY
[0085] The present invention is applicable to a valve opening and closing timing control apparatus controlling a relative rotational phase of a driven-side rotating body relative to a driving-side rotating body which rotates synchronously with a crankshaft of an internal combustion engine.
EXPLANATION OF REFERENCE NUMERALS
[0086] 1 housing (driving-side rotating body) [0087] 2 inner rotor (driven-side rotating body) [0088] 4 fluid pressure chamber [0089] 45a second flow passage [0090] 5 first member [0091] 5g first flow passage [0092] 52 spool [0093] 6 second member [0094] 61 supply flow passage [0095] 63 pin (fixing member) [0096] 8 intermediate lock mechanism [0097] 10 valve opening and closing timing control apparatus [0098] 45 lock flow passage [0099] 51 OCV (electromagnetic valve) [0100] 101 camshaft [0101] B bolt [0102] C crankshaft [0103] E engine (internal combustion engine) [0104] L intermediate lock phase [0105] P pump [0106] X axis [0107] Y press-fitting direction