JP7180109B2 - Valve timing control device - Google Patents

Description

The present invention relates to a valve timing control device for controlling valve timing of an internal combustion engine.

The valve opening/closing timing control device disclosed in Patent Document 1, the source of which is given below, has a valve unit installed in the inner space of a cylindrical connecting bolt (4) that connects a driven rotating body (2) and a camshaft (3). (10) (see, for example, Figs. 1 and 3, etc. Reference numerals in parentheses in the background art refer to references. The same shall apply hereinafter). This valve unit (10) is provided with a stopper (12b) to prevent the spool (11) from slipping off in the axial direction.

Further, the valve unit (1) included in the camshaft adjusting device disclosed in Patent Document 2, the source of which is given below, is also formed in the internal space of a cylindrical screw (12) passing through the axis (for example, Fig. 1). 1st prize). This valve unit (1) is provided with a fixing ring (32) to prevent the sleeve (3), on which the spool (2) slides within the set range, from slipping out axially from the internal space of the screw (12). It has

U.S. Pat. No. 9,863,288 U.S. Patent Application Publication No. 2015/0300212

The stopper (12b) in Patent Document 1 is installed in a mounting groove that is recessed radially outward from the sliding surface on which the spool (11) slides. For this reason, the stopper (12b) may be installed at a position offset from the mounting groove in the axial direction, and the range of motion of the spool (11) may become inappropriate. In addition, the fixing ring (32) in US Patent Application Publication No. 2015/0300212 also has a sleeve (3) inserted into the inner space of the screw (12) and extends radially outward from the contact surface that contacts the inner space. It is adapted to be installed in a recessed mounting groove. For this reason, the sleeve (3) may also be installed with its position shifted from the mounting groove in the direction, and the installation position of the valve unit (1) may not be appropriate. If the mounting positions of the stopper (12b), the fixing ring (32), etc. are inspected in order to suppress the above-described mounting problems, the number of processes increases, leading to an increase in cost.

In view of the above, it is desired to provide a technique for appropriately installing a locking member that restricts the axial movement of the valve unit in the valve timing control device.

In view of the above, the characteristic configuration of the valve opening/closing timing control device is as follows: a drive-side rotor that rotates synchronously with a crankshaft of an internal combustion engine; a driven-side rotating body that rotates integrally with the camshaft; an advance chamber and a retarding chamber formed between the driving-side rotating body and the driven-side rotating body; A connection bolt that connects the driven-side rotating body to the camshaft and has an internal space formed coaxially with the rotation axis, and a valve unit that controls supply and discharge of fluid to the advance chamber and the retard chamber. wherein the valve unit includes a spool that is slidable in both directions along the rotation axis along the inner peripheral surface of the bolt that forms the internal space of the connecting bolt; a locking member that restricts movement in the axial direction along the rotation axis, and the spool is inserted into the internal space formed from the head side of the connecting bolt toward the camshaft. inserted and
The internal space includes a region with a first inner diameter formed on the head side, a region with a second inner diameter smaller than the first inner diameter, and an inner space smaller than the second inner diameter inside the bolt in which the spool slides. A third inner diameter area, which is the inner diameter of the peripheral surface, is formed in the area from the head side toward the camshaft in this order,
An engaging groove having a larger diameter than the first inner diameter and recessed radially outward is formed in the boundary between the region of the first inner diameter and the region of the second inner diameter so that the locking member is engaged therewith. Between the second inner diameter region and the third inner diameter region , the engagement groove is formed in the second inner diameter region such that the diameter decreases from the second inner diameter region toward the third inner diameter region. The entire region extending from the position adjacent to the third inner diameter region toward the region of the third inner diameter is inclined with respect to the rotation axis as a single tapered inner surface .

According to this configuration, since the second inner diameter is smaller than the first inner diameter, it is difficult for the engaging member to enter the second axial side of the engaging groove. That is, since the spool is inserted into the internal space from the first side in the axial direction toward the second side in the axial direction, the locking member is also inserted into the internal space from the first side in the axial direction toward the second side in the axial direction. be. The first inner diameter on the first side in the axial direction of the engaging groove is secured to have a diameter through which the locking member can pass. Since the second inner diameter on the second side in the axial direction of the engagement groove is smaller than the first inner diameter, the second inner diameter is on the second side in the axial direction of the engagement groove compared to the first side in the axial direction of the engagement groove. makes it difficult for the locking member to pass through. Therefore, the locking member can be properly engaged with the engagement groove. Thus, according to this configuration, it is possible to appropriately install the locking member that restricts the axial movement of the valve unit in the valve timing control device.

Here, it is preferable that the locking member is a snap ring whose radial length can be changed between a maximum diameter and a minimum diameter, and that the second inner diameter is smaller than the minimum diameter.

As described above, the spool is inserted into the internal space from the first axial side toward the second axial side, and the locking member is also inserted into the internal space from the first axial side toward the second axial side. be done. It is sufficient that the first inner diameter on the first side in the axial direction of the engagement groove has a diameter through which the locking member can pass. If the locking member is a snap ring, the first inner diameter should be such that the snap ring with the smallest diameter can pass through. Further, if the second inner diameter is smaller than the minimum diameter of the snap ring, even in a state where the snap ring can easily pass through, it cannot progress to the second side in the axial direction from the engagement groove. Therefore, the engaging member can be properly installed.

Further, the engagement groove includes a bottom portion along the inner peripheral surface of the bolt, a first wall portion rising radially inward from the bottom portion on the side of the area of the first inner diameter , and a wall portion extending from the bottom portion to the second inner diameter. a second wall portion rising radially inward on the side of the region , and the inner diameter of the internal space at the radially inner end portion of the second wall portion is the internal space in the region where the spool slides. is preferably larger than the inner diameter of the

As described above, the spool is inserted into the internal space from the first axial side toward the second axial side. In the internal space, the sliding surface on which the spool slides is required to have high liquid-tightness. In many cases, after forming the inner space, finishing treatment such as polishing is performed. The polishing device or the like is inserted into the internal space from the first side in the axial direction toward the second side in the axial direction, and processes the inner peripheral surface of the internal space that serves as a sliding surface. For this reason, it is preferable that the inner diameter of the internal space on the opening side located on the first side in the axial direction of the sliding surface is larger than the inner diameter of the sliding surface. The engagement groove may be provided continuously on the sliding surface, or may be provided apart from the sliding surface. When the engagement groove is provided away from the sliding surface and on the first side in the axial direction of the sliding surface, the inner diameter of the internal space at the radially inner end of the second wall portion is equal to the sliding surface in the internal space. If the diameter is larger than the inner diameter of the internal space, the diameter on the opening side of the internal space can be made large, which is preferable.

Further features and advantages of the valve timing control device will become clear from the following description of the embodiments described with reference to the drawings.

1 is an axial cross-sectional view of a valve timing control device; FIG. It is an axial cross-sectional view of a valve timing control device. FIG. 4 is an axial cross-sectional view of the valve unit; It is an exploded perspective view of a valve unit. FIG. 4 is a plan view of the snap ring in the maximum diameter state; FIG. 4 is a plan view of the snap ring in the minimum diameter state; FIG. 4 is a schematic enlarged view showing an example of the concept of the structure around the engagement groove; FIG. 10 is a schematic enlarged view showing another example of the concept of the structure around the engagement groove;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. A valve opening/closing timing control device 100 shown in FIG. By changing the relative rotation phase of the , the opening/closing timing of the intake valve in the vehicle internal combustion engine EN is controlled. As shown in FIGS. 1 and 2, in the valve opening/closing timing control device 100, when the relative rotational phase is displaced in the advance direction S1, the intake compression ratio is increased as the amount of displacement increases, and the relative rotational phase is retarded. The relationship between the crankshaft E1, which is the drive shaft of the internal combustion engine, and the intake camshaft 3 (valve opening/closing camshaft) is set so that the intake compression ratio is reduced as the amount of displacement increases when displacing in the direction S2. It is

Here, the intake camshaft 3 is exemplified as the valve opening/closing camshaft, and the valve opening/closing timing control device 100 controls the opening/closing timing of the intake valve. It may be an exhaust camshaft, and the valve opening/closing timing control device 100 may control the opening/closing timing of the exhaust valve.

As shown in FIGS. 1 to 3, the valve timing control device 100 has an outer rotor 1 made of, for example, an aluminum alloy, an inner rotor 2 made of, for example, an aluminum alloy and steel, and connecting bolts 4 made of steel. . The external rotor 1 is a drive-side rotating body that rotates synchronously with the crankshaft E1 of the internal combustion engine EN. The internal rotor 2 is arranged on the radially inner side R1 of the external rotor 1, supported coaxially with the rotational axis X of the external rotor 1, and integrally rotated with the intake camshaft 3. As shown in FIG. The internal rotor 2 is a driven rotating body that is driven to rotate as the external rotor 1 rotates. A connecting bolt 4 is inserted into the inner rotor 2 to fix the inner rotor 2 to the intake camshaft 3 . The connection bolt 4 is arranged coaxially with the rotation axis X and connects the internal rotor 2 to the intake camshaft 3 . An internal space 40 is formed in the connecting bolt 4 coaxially with the rotation axis X. As shown in FIG.

The internal rotor 2 has an aluminum alloy internal rotor body 2a and a cylindrical steel adapter 2b to which the rotation of the internal rotor body 2a is transmitted. The internal rotor body 2a and the adapter 2b, the adapter 2b and the intake camshaft 3 are fixed by keys fitted to their joint surfaces so as not to rotate relative to each other. The materials of the outer rotor 1 and the inner rotor main body 2a are not limited to aluminum alloys, and may be formed of various metal materials such as steel. Moreover, the material of the adapter 2b is not limited to steel, and various metal materials such as an aluminum alloy may be used.

In this embodiment, the internal rotor body 2a is arranged on the first axial side L1, the adapter 2b is arranged on the second axial side L2, and the intake camshaft 3 is arranged further on the second axial side L2 than the adapter 2b. are placed. The internal rotor main body 2a and the adapter 2b are fitted together in the direction of the rotation axis X (axial direction L) and supported so as to be relatively rotatable with respect to the external rotor 1. As shown in FIG. The connecting bolt 4 penetrates the adapter 2b from the side of the internal rotor main body 2a (axial first side L1), and rotates the internal rotor main body 2a, the adapter 2b, and the intake camshaft 3 with respect to the intake camshaft 3. It is tightened and fixed so as to be coaxial with the axis X.

The connecting bolt 4 has a fitting shaft portion 4a that fits coaxially with the rotation axis X inside the internal rotor body 2a, the adapter 2b, and the intake camshaft 3, and a female screw formed in a bolt hole of the intake camshaft 3. and a male threaded portion 4b that is screwed onto the portion 3a.

The intake camshaft 3 is a rotary shaft of a cam that controls the opening and closing of intake valves of the internal combustion engine EN, and rotates synchronously with the internal rotor main body 2a, the adapter 2b and the connecting bolt 4. The intake camshaft 3 is rotatably attached to the cylinder head of the internal combustion engine EN.

The external rotor 1 includes a front plate 1a provided on the side opposite to the side of the intake camshaft 3, an external rotor body 1b arranged radially outward R2 of the internal rotor body 2a, and a timing sprocket 5 integrally. The rear plate 1c is integrally connected with the provided rear plate 1c by a fastening bolt 1d. The timing sprocket 5 has a wide toothed portion 5a, and an endless rotating body E2 such as a toothed rubber belt interlocked with the crankshaft E1 is wound thereon. The timing sprocket 5 may be formed in a flat plate shape around which a metal chain is wound.

When the crankshaft E1 is rotationally driven, rotational power is transmitted to the timing sprocket 5 by the endless rotating body E2, and the external rotor 1 is rotationally driven in the rotational direction S shown in FIG. As the external rotor 1 is driven to rotate, the internal rotor 2 is driven to rotate in the rotational direction S to rotate the intake camshaft 3, and the cam provided on the intake camshaft 3 pushes down the intake valve of the engine to open it.

As shown in FIG. 2, the inner rotor body 2a is accommodated in the radially inner side R1 of the outer rotor 1, and a fluid pressure chamber 6 is defined between the outer rotor 1 and the inner rotor body 2a. The fluid pressure chamber 6 is formed on the outer rotor body 1b with a plurality of protrusions 1e protruding radially inward R1 at intervals in the circumferential direction C (rotational direction S). It is formed between the rotor main body 1b. The fluid pressure chamber 6 is partitioned into an advance chamber 6a and a retard chamber 6b in the circumferential direction C by a vane portion 2c formed on a portion of the outer peripheral surface of the internal rotor body 2a facing the fluid pressure chamber 6. .

Hydraulic pressure acts on the vane portion 2c by supplying or discharging oil as working fluid to the advance chamber 6a and the retard chamber 6b, or by interrupting the supply and discharge thereof. Oil is supplied to and discharged from the advance chamber 6a through an advance port 25b, an advance annular passage 22, and an advance passage 20 (see FIGS. 3, 4, etc.). Oil is supplied to and discharged from the retarded angle chamber 6 b via the retarded angle port 25 c , the annular retarded angle flow path 23 , and the retarded angle flow path 19 . In this manner, the relative rotational phase is displaced in the advancing direction or the retarding direction, or held at an arbitrary phase. The advancing direction is the direction in which the volume of the advancing chamber 6a increases as indicated by an arrow S1 in FIG. The retarded angle direction is the direction in which the volume of the retarded angle chamber 6b increases as indicated by arrow S2 in FIG. The relative rotational phase when the volume of the advance chamber 6a is maximized is the most advanced phase, and the relative rotational phase when the volume of the retarded chamber 6b is maximized is the most retarded phase.

Further, the valve opening/closing timing control device 100 includes a lock mechanism 9 for fixing the relative rotation phase at a predetermined lock phase, as shown in FIG. The lock mechanism 9 restrains the relative rotational movement of the internal rotor body 2a with respect to the external rotor 1, thereby setting the relative rotational phase of the internal rotor body 2a with respect to the external rotor 1 to a predetermined value between the most advanced phase and the most retarded phase. lock phase. The lock mechanism 9 engages the front plate 1a or the rear plate 1c with the lock member 9a, which moves forward and backward in the axial direction L by hydraulic pressure, to restrain the lock phase.

In this embodiment, a valve unit 10 as an electromagnetic control valve for controlling the supply and discharge of oil to the advance chamber 6a and the retard chamber 6b is arranged coaxially with the intake camshaft 3. As shown in FIG. The valve unit 10 switches oil supply/discharge to/from the fluid pressure chamber 6 so that the relative rotational phase of the internal rotor body 2a with respect to the external rotor 1 is changed between the most advanced phase and the most retarded phase. As shown in FIGS. 1, 3 and 4, the valve unit 10 includes a spool 11, a spool spring 12, an electromagnetic solenoid 13, a locking member 8, a check valve 27, an oil filter 26, a sleeve 41.

The spool 11 slides in both directions along the rotation axis X on the bolt inner peripheral surface 4p forming the internal space 40 of the connecting bolt 4 . A spool spring 12 biases the spool 11 as described below. The electromagnetic solenoid 13 drives the spool 11 against the biasing force of the spool spring 12 . The locking member 8 restricts the movement of the spool 11 in the axial direction L along the rotation axis X at the bolt inner peripheral surface 4p. In this embodiment, the locking member 8 restricts the movement of the spool 11 toward the first side L1 in the axial direction. The check valve 27 prevents reverse flow of oil from the first axial side L1 to the second axial side L2. The oil filter 26 filters impurities such as metal particles contained in the oil. The tubular sleeve 41 is arranged so as to contact the outer peripheral surface of the fitting shaft portion 4 a of the connecting bolt 4 .

The spool spring 12 is mounted between the spring bearing 15 and the spool 11 on the second axial side L2 of the internal space 40, and always biases the spool 11 toward the first axial side L1. When the electromagnetic solenoid 13 is energized, the push pin 13a provided on the electromagnetic solenoid 13 presses the spool 11, and the spool 11 slides against the biasing force of the spool spring 12 to the second side in the axial direction. The valve unit 10 adjusts the position of the spool 11 by adjusting the duty ratio of electric power supplied to the electromagnetic solenoid 13 by an ECU (Electronic Control Unit) (not shown).

As shown in FIG. 1 , oil is supplied to the valve unit 10 by an oil pump P through a supply flow path 21 . The supplied oil is filtered by the oil filter 26 and supplied to the spool 11 through the check valve 27 . The check valve 27 is closed when the supply pressure of the oil from the supply passage 21 is equal to or lower than the set pressure, and cuts off the supply of oil from the axial second side L2 to the axial first side L1. , to prevent reverse flow of oil from the first axial side L1 to the second axial side L2. The check valve 27 includes a ball valve body 27b, a holder 27c, and a spring 27d. The spring 27d constantly urges the ball valve body 27b against the valve seat 27a (see FIG. 3) provided in the holder 27c to block the flow path. When the supply pressure of the oil from the supply channel 21 exceeds the biasing force of the spring 27d, the channel is released and the oil is supplied to the spool 11.

By the way, when installing the valve unit 10 in the internal space 40 of the connecting bolt 4, in this embodiment, the spool 11 is located on the other side from the first axial side L1, which is the side of the head 4c of the connecting bolt 4. It is inserted into the internal space 40 toward the second axial side, which is the side of the fitting shaft portion 4a. After that, the locking member 8 is also inserted into the internal space 40 from the first axial side L1 toward the second axial side. The locking member 8 is engaged with an engaging groove 80 recessed radially outward R2 along the circumferential direction C on the bolt inner peripheral surface 4p, and the spool 11 is engaged on the first axial side L1 of the bolt inner peripheral surface 4p. Movement to the first side L1 in the axial direction is restricted. As shown in FIG. 3 , the internal space 40 has an inner diameter on the second axial side L2 of the engaging groove 80 compared to the first inner diameter φ1, which is the inner diameter on the first axial side L1 of the engaging groove 80. is smaller than the second inner diameter φ2.

A first inner diameter φ1 on the first side L1 in the axial direction of the engagement groove 80 has a diameter through which the locking member 8 can pass. Since the second inner diameter φ2 on the axial second side L2 of the engaging groove 80 is smaller than the first inner diameter φ1, the engaging groove 80 is smaller than the engaging groove 80 on the axial first side L1. Also, it is difficult for the locking member 8 to pass through the second side L2 in the axial direction. If the first inner diameter φ1 of the first axial side L1 and the second inner diameter φ2 of the second axial side L2 across the engaging groove 80 are the same, the locking member 8 is assembled. 8 may go beyond the engagement groove 80 and enter the axial second side L2. In order to prevent the engaging member 8 from exceeding the engaging groove 80 and entering the second side L2 in the axial direction, the insertion depth must be controlled when the engaging member 8 is assembled. It is necessary to increase inspection man-hours and devise assembly jigs. However, by setting the second inner diameter φ2 to be smaller than the first inner diameter φ1, the possibility of the locking member 8 exceeding the engaging groove 80 and entering the second side L2 in the axial direction is suppressed. The member 8 can be properly engaged with the engagement groove 80 . Preferably, the second inner diameter φ2 is a diameter through which the locking member 8 cannot pass.

In this way, by structurally preventing the locking member 8 from entering the axial direction second side L2 beyond the engaging groove 80, the locking member inserted into the internal space 40 from the axial direction first side L1 The locking member 8 can be attached by abutting the locking member 8 against the wall surface of the engaging groove 80 (the second wall portion 82 shown in FIGS. 7 and 8). In other words, the assembly process is facilitated, and a process for inspecting whether the locking member 8 has been properly attached is no longer necessary.

Also, the width of the engaging groove 80 in the axial direction L (the width of the bottom portion 83 shown in FIGS. 7 and 8) and the thickness of the locking member 8 (the width in the axial direction L when attached to the internal space 40) , the relative positions in the axial direction L between the engagement groove 80 and the locking member 8 differ for each valve unit 10 . Therefore, the flow rate of the oil in the valve unit 10 is also different for each valve unit 10 . However, as described above, by disposing the locking member 8 against the second wall portion 82, the oil flow rate of the valve unit 10 can be made uniform. Thereby, the flow rate performance of the valve unit 10 can be stabilized.

As shown in FIGS. 5 and 6, the locking member 8 is preferably a snap ring. The snap ring can vary in radial length between a maximum diameter and a minimum diameter. FIG. 5 shows the locking member 8 with a maximum diameter of φ81, and FIG. 6 shows the locking member 8 with a minimum diameter of φ82. The first inner diameter φ1 is preferably at least larger than the minimum diameter φ82, and the second inner diameter φ2 is preferably smaller than the minimum diameter φ82.

As described above, the spool 11 is inserted into the inner space 40 from the first axial side L1 toward the second axial side L2, and the locking member 8 is also inserted from the first axial side L1 toward the second axial side L2. is inserted into the internal space 40 toward the . The first inner diameter φ1 on the first side L1 in the axial direction from the engaging groove 80 should just have a diameter through which the locking member 8 can pass. When the locking member 8 is a snap ring, the first inner diameter φ1 should be a diameter that allows the snap ring with the minimum diameter φ82 to pass through. Further, if the second inner diameter φ2 is smaller than the minimum diameter φ82 of the snap ring, the locking member 8 is located on the second axial side of the engaging groove 80 even when the snap ring is most easily passed through. Cannot progress to L2. Therefore, the locking member 8 can be properly installed.

By the way, it is preferable that the sliding surface 4s, which is the area on which the spool 11 slides in the bolt inner peripheral surface 4p of the internal space 40, is in contact with the spool 11 with high liquid-tightness. Therefore, in many cases, after the internal space 40 is formed by primary processing (rough processing), the sliding surface 4s is subjected to finishing treatment such as polishing by secondary processing. In the finishing process, a polishing device or the like is inserted into the internal space 40 from the axial first side L1 toward the axial second side L2 to process the inner peripheral surface of the internal space 40 that will be the sliding surface 4s. For this reason, the internal space 40 preferably has a larger inner diameter on the opening side located on the first side L1 in the axial direction than the sliding surface 4s compared to the inner diameter of the sliding surface 4s. The engagement groove 80 can also be machined by adjusting the program or the like for the primary machining. Therefore, except for the initial cost, there is almost no increase in processing cost for forming the engagement groove 80 so that the second inner diameter φ2 is smaller than the first inner diameter φ1.

7 and 8 schematically show the concept of the structure around the engagement groove 80. FIG. As shown in FIG. 7, the engagement groove 80 may be provided continuously from the sliding surface 4s, but as shown in FIG. 80 may be provided. In the embodiment described above with reference to FIGS. 1 and 3, the area indicated by reference numeral L3 in FIG. 3 is the area (sliding area L3) in which the spool 11 slides. The inner diameter of the internal space 40 is inclined radially inward R1 so that the inner diameter decreases from the engagement groove 80 toward the axial second side L2. Therefore, the third inner diameter φ3, which is the inner diameter of the internal space 40 (the diameter of the sliding surface 4s) in the sliding area L3, is smaller than the second inner diameter φ2.

As shown in FIGS. 7 and 8, the engagement groove 80 includes a bottom portion 83 along the bolt inner peripheral surface 4p and a first wall portion 81 rising from the axial first side L1 of the bottom portion 83 to the radially inner side R1. , and a second wall portion 82 rising radially inward R1 from the second axial side L2 of the bottom portion 83 . The inner diameter (first inner diameter φ1) of the internal space 40 on the first side L1 in the axial direction from the first wall portion 81 is larger than the minimum diameter φ82 of the snap ring as described above. The inner diameter of the inner space 40 at the end of the radially inner side R1 of the first wall portion 81 is equal to the inner diameter of the engaging groove 80. It is preferably the smallest on the first side L1 in the axial direction and larger than the minimum diameter φ82 of the snap ring.

The inner diameter (second inner diameter φ2) of the internal space 40 at the end of the radially inner side R1 of the second wall portion 82 is preferably smaller than the first inner diameter φ1 and smaller than the minimum diameter φ82 of the snap ring. As shown in FIG. 7, when the engagement groove 80 is provided continuously from the sliding surface 4s, the inner diameter of the internal space 40 (second The inner diameter φ2) is equal to the third inner diameter φ3, which is the diameter of the sliding surface 4s. As shown in FIG. 8, when the engaging groove 80 is provided at a position away from the sliding surface 4s in the axial direction L, the inner space 40 at the end portion of the radially inner side R1 of the second wall portion 82 (second inner diameter φ2) is larger than the third inner diameter φ3, which is the diameter of the sliding surface 4s.

As described above, the finishing treatment for forming the sliding surface 4s requires a certain amount of man-hours, so it is preferable to perform the finishing treatment only on the necessary regions. Moreover, in the vicinity of the engagement groove 80, there is a possibility that the sliding surface 4s may be damaged by inserting the locking member 8 or the like. Therefore, it is preferable that the sliding surface 4s be formed apart from the engaging groove 80. As shown in FIG. In such a case, the inner diameter (second inner diameter φ2) of the internal space 40 at the end portion of the radially inner side R1 of the second wall portion 82 is the same as that of the internal space 40 in the sliding region L3 where the spool 11 slides. is preferably larger than the inner diameter of (third inner diameter φ3).

[Other embodiments]
Other embodiments will be described below. The configuration of each embodiment described below is not limited to being applied alone, and can be applied in combination with the configuration of other embodiments as long as there is no contradiction.

(1) In the above description, the spool 11 extends from the first axial side L1, which is the side of the head portion 4c of the connecting bolt 4, toward the second axial side, which is the side of the fitting shaft portion 4a, which is the other side. In the above description, the form of insertion into the internal space 40 has been exemplified. However, this does not prevent the spool 11 from being inserted into the internal space 40 from the fitting shaft portion 4 a side of the connecting bolt 4 toward the head portion 4 c side of the connecting bolt 4 . That is, the first axial side L1 may be either the side of the head 4c of the connecting bolt 4 or the side of the fitting shaft portion 4a, and the second axial side L2 may be the side of the head 4c. side or the side of the fitting shaft portion 4a.

(2) In the above description, the spool 11 is regulated by the locking member 8 on the inner peripheral surface 4p of the bolt. However, a sleeve is arranged in the internal space 40 of the connecting bolt 4, the spool 11 is arranged radially inside R1 of the sleeve, and the sleeve is locked by the locking member 8 on the bolt inner peripheral surface 4p. good too. In this case as well, the movement of the spool 11 in the axial direction L is indirectly restricted by the locking member 8 .

INDUSTRIAL APPLICABILITY The present invention can be used in a valve timing control device for controlling the valve timing of an internal combustion engine.

1: External rotor (drive-side rotating member)
1d: fastening bolt 2: internal rotor (driven side rotating member)
3: Intake camshaft (camshaft for valve opening and closing)
4: Connecting bolt 4a: Fitting shaft (shaft of connecting bolt)
4c: head 4p: bolt inner peripheral surface 4s: sliding surface 6a: advance chamber 6b: retard chamber 8: locking member 10: valve unit 11: spool 40: internal space 80: engagement groove 81: first Wall portion 82 : Second wall portion 83 : Bottom portion 100 : Valve timing control device C : Circumferential direction E1 : Crankshaft EN : Internal combustion engine L : Axial direction L1 : Axial direction first side L2 : Axial direction second side L3 : Sliding area (area where the spool slides)
R1: radially inner side R2: radially outer side S: rotation direction X: rotation axis φ1: first inner diameter φ2: second inner diameter φ3: third inner diameter (inner diameter of the internal space in the area where the spool slides)
φ81: Maximum diameter φ82: Minimum diameter

Claims (3)

a drive-side rotor that rotates synchronously with a crankshaft of an internal combustion engine;
a driven-side rotating body arranged coaxially with the rotation axis of the driving-side rotating body and rotating integrally with a camshaft for opening and closing the valve;
an advance chamber and a retard chamber formed between the drive-side rotor and the driven-side rotor;
a connecting bolt that is arranged coaxially with the rotation axis and connects the driven-side rotating body to the camshaft, and that has an internal space formed coaxially with the rotation axis;
a valve unit that controls supply and discharge of fluid to and from the advance chamber and the retard chamber;
The valve unit includes a spool that can slide in both directions along the rotation axis on the inner peripheral surface of the bolt that forms the internal space of the connecting bolt, and the rotation axis of the spool on the inner peripheral surface of the bolt. a locking member that restricts axial movement along the
The spool is inserted into the internal space formed from the head side of the connecting bolt toward the camshaft,
The internal space includes a region with a first inner diameter formed on the head side, a region with a second inner diameter smaller than the first inner diameter, and an inner space smaller than the second inner diameter inside the bolt in which the spool slides. A third inner diameter area, which is the inner diameter of the peripheral surface, is formed in the area from the head side toward the camshaft in this order,
An engaging groove having a larger diameter than the first inner diameter and recessed radially outward is formed in the boundary between the region of the first inner diameter and the region of the second inner diameter so that the locking member is engaged therewith. Between the second inner diameter region and the third inner diameter region , the engagement groove is formed in the second inner diameter region such that the diameter decreases from the second inner diameter region toward the third inner diameter region. A valve opening/closing timing control device in which the entire area extending from a position adjacent to the third inner diameter area toward the area of the third inner diameter is inclined with respect to the rotation axis as a single tapered inner surface . 2. The valve according to claim 1, wherein the locking member is a snap ring whose radial length is variable between a maximum diameter and a minimum diameter, and the second inner diameter is smaller than the minimum diameter. Open/close timing control device. The engagement groove includes a bottom portion along the inner peripheral surface of the bolt, a first wall portion rising radially inward from the bottom portion on the side of the region of the first inner diameter, and a region of the second inner diameter from the bottom portion. a second wall portion rising radially inward on the side;
3. The valve according to claim 1 or 2, wherein the internal space at the radially inner end of the second wall has a larger diameter than the internal space at the region where the spool slides. Open/close timing control device.

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