JP4905843B2 - Valve timing adjustment device - Google Patents

Abstract

A valve timing adjuster includes a housing and a vane rotor. A hub portion of the vane rotor includes an advance passage and a retard passage. One of a shoe of the housing and the hub portion includes an advance groove and a retard groove. The advance groove provides communication between an advance chamber and the advance passage at a full retard position. The retard groove provides communication between a retard chamber and the retard passage at a full advance position. The advance groove and the retard groove are spaced apart from each other along a longitudinal axis of the housing.

Description

  The present invention relates to a valve timing adjusting device for an internal combustion engine (hereinafter referred to as “engine”) that adjusts the opening / closing timing of at least one of an intake valve and an exhaust valve.

Conventionally, an intake valve and an exhaust gas are changed by changing the phase of a crankshaft as an engine drive shaft and a camshaft as a driven shaft that is rotationally driven by the driving force of the crankshaft to open and close the intake valve and the exhaust valve. A valve timing adjusting device that adjusts the opening / closing timing of at least one of the valves is known.
Generally, the valve timing adjusting device includes a housing that rotates together with a crankshaft, and a vane rotor that is housed in the housing and rotates together with the camshaft. The housing has a shoe extending radially inward from the cylindrical peripheral wall and slidingly contacting the outer wall of the vane rotor, and a plurality of pressure chambers partitioned by the shoe are formed between the inner wall of the housing and the outer wall of the vane rotor. The vane rotor has a plurality of vanes that divide the plurality of pressure chambers into an advance chamber and a retard chamber. The hydraulic pressure supplied to the advance chamber or the retard chamber acts on the pressure receiving surfaces of the plurality of vanes, so that the housing and the vane rotor rotate relative to each other to change the phases of the crankshaft and the camshaft.

By the way, the valve timing adjusting apparatus is required to expand the phase conversion angle in order to adapt to various operating conditions of the engine and improve the engine performance and the exhaust gas purification performance. Moreover, in order to improve the mounting property to an engine, size reduction of the physique is calculated | required.
In order to expand the phase conversion angle of the valve timing adjusting device, it is considered to reduce the number of pressure chambers and vanes and increase the volume of each remaining pressure chamber in the circumferential direction. However, if the number of vanes is reduced, the total area on which the vanes are subjected to hydraulic pressure is reduced, so that the torque acting on the housing and the vane rotor is reduced. If this torque is smaller than the reaction force of the camshaft, it becomes difficult to drive the housing and the vane rotor relative to each other. For this reason, there exists a possibility that the engine speed which can perform phase control of the valve timing adjusting device may be limited.
On the other hand, if the pressure receiving surface of the vane is increased in order to increase the torque acting on the housing and the vane rotor, there is a concern that the physique of the valve timing adjusting device may be increased.

  In Patent Document 1, in a valve timing adjustment device in which the hydraulic pressure for advance control is set higher than the hydraulic pressure for retard control, the advance passage and the retard chamber are supplied with hydraulic pressure at the most retarded position. The advance angle passage and the retard angle passage are formed so that the angle θ formed by the delay angle passage that supplies the pressure is larger than the angle φ formed by the advance angle passage and the retard angle passage at the most advanced angle position. Thereby, oil leakage between the advance chamber and the retard chamber when the advance control is performed from the most retarded position is suppressed.

Japanese Patent No. 3906482

However, in Patent Document 1, the advance passage is formed in a curved shape on the outer wall of the vane rotor, and the retard passage is formed on the inner wall of the rear plate. If the advance passage is formed in a curved shape and the advance passage and the retard passage are formed as separate members in this way, the configuration of each passage becomes complicated and the processing man-hour may increase.
The present invention has been made in view of the above problems, and its purpose is to suppress the leakage of the working fluid between the advance chamber and the retard chamber, thereby expanding the phase conversion angle and reducing the size of the physique. It is an object of the present invention to provide a valve timing adjusting device that can be realized.
Another object of the present invention is to provide a valve timing adjusting device that simplifies the configuration of a supply passage for supplying a working fluid to an advance chamber and a retard chamber and reduces the number of processing steps.

According to the first aspect of the present invention, a valve timing adjusting device includes a housing that rotates with one of a drive shaft and a driven shaft, and a vane rotor that is provided substantially coaxially with the housing and rotates with the other of the drive shaft and the driven shaft. Prepare. The housing includes a cylindrical peripheral wall, a shoe protruding radially inward from the peripheral wall, a front plate provided on one side in the axial direction of the peripheral wall, and a rear plate provided on the other side in the axial direction of the peripheral wall. The vane rotor has a substantially cylindrical boss that is slidably in contact with the inner slidable contact surface of the shoe, and a pressure chamber that protrudes radially outward from the boss and is formed on both sides of the shoe in the circumferential direction. The vane is partitioned into a chamber and is rotated relative to the housing by the pressure of the working fluid supplied to the advance chamber or the retard chamber.
When the vane rotor is at the most retarded position with respect to the housing, the boss portion has an advance passage where the opening is located on the advance chamber side of the sliding surface, and when the vane rotor is at the most advanced position with respect to the housing, There is a retard passage in which an opening is located on the retard chamber side of the sliding surface. The shoe has an advance groove that communicates the opening of the advance passage and the advance chamber when the vane rotor is at the most retarded position with respect to the housing, and a shoe when the vane rotor is at the most advanced position with respect to the housing. A retard groove that communicates the opening of the angular passage with the retard chamber; Of these advance and retard grooves, one groove is provided on the rear plate side of the sliding contact surface, and the other groove is provided on the front plate side of the sliding contact surface.

By providing both the advance passage and the retard passage in the vane rotor and consolidating the supply passages into one part, the configuration of the supply passages can be simplified and the number of processing steps can be reduced. Further, by providing these supply passages in the vane rotor without providing them in the rear plate, it is possible to prevent the working fluid from leaking from the supply passage to the advance chamber or the retard chamber through the gap between the vane rotor and the rear plate. be able to.
Furthermore, in the first aspect of the present invention, one of the advance groove and the retard groove is provided on the rear plate side of the sliding contact surface, and the other groove is provided on the front plate side of the sliding contact surface. As described above, the advance groove and the retard groove are diagonally formed on the sliding contact surface, and the distance between the advance groove and the retard groove is increased, so that the operation by the sliding contact surface and the outer wall of the boss portion is performed. Fluid sealing performance is improved. That is, leakage of the working fluid between the advance chamber formed on one side of the shoe in the circumferential direction and the retard chamber formed on the other side can be suppressed.
In addition, by providing the advance groove and the retard groove diagonally on the sliding contact surface, the advance groove and the retard groove can be brought closer to the circumferential direction, and the shoe can be formed smaller in the circumferential direction. . Accordingly, the phase conversion angle of the valve timing adjusting device can be expanded by forming the pressure chamber larger in the circumferential direction.
In addition, since the shoe can be formed small in the circumferential direction, the physique of the valve timing adjusting device can be reduced in size by forming the shoe small in the axial direction or the radial direction.
Further, the torque can be increased by increasing the number of vanes as much as the shoe is formed smaller in the circumferential direction.

  According to the second aspect of the present invention, the advance groove and the retard groove extend in the circumferential direction without extending the sliding contact surface in the axial direction. Accordingly, it is possible to cut the sliding contact surface in the circumferential direction by, for example, milling and the like to form the advance groove and the retard groove, thereby reducing the man-hours for the advance groove and the retard groove. it can.

  According to the invention described in claim 3, the shoe has an advance groove and a retard groove on its outer wall instead of the advance groove and the retard groove. Of these advance and retard grooves, one groove is provided on the rear plate side of the outer wall of the boss portion, and the other groove is provided on the front plate side of the outer wall of the boss portion. In this way, by providing the advance and retard grooves diagonally on the outer wall of the boss between the vanes, the sealing area between the sliding contact surface and the outer wall of the boss is expanded, and the sealing performance is improved. To do. Thus, the same effect as that of the first aspect can be achieved.

  According to the invention described in claim 4, the advance groove and the retard groove extend in the circumferential direction without extending the outer wall of the boss portion in the axial direction. As a result, the outer wall of the boss part can be cut in the circumferential direction by, for example, milling, etc., so that advance and retard grooves can be formed, so that the man-hours for advance and retard grooves can be reduced. Can do.

It is sectional drawing of the valve timing adjustment apparatus by 1st Embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is a schematic diagram of the driving force transmission system to which the valve timing adjusting device according to the first embodiment of the present invention is applied. It is a figure which shows only the surrounding wall and shoe of the valve timing adjustment apparatus by 1st Embodiment. It is a V direction arrow directional view of FIG. It is a principal part enlarged view of the surrounding wall and shoe of the valve timing adjustment apparatus by 2nd Embodiment of this invention. It is sectional drawing of the valve timing adjustment apparatus by 3rd Embodiment of this invention. It is the VIII-VIII sectional view taken on the line of FIG. It is a figure which shows only the vane rotor of the valve timing adjustment apparatus by 3rd Embodiment. FIG. 10 is a view in the direction of arrow X in FIG. 9. It is a principal part enlarged view of the vane rotor of the valve timing adjustment apparatus by 4th Embodiment of this invention. It is a principal part enlarged view of the surrounding wall and shoe of the valve timing adjustment apparatus of a comparative example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 to 5 show a valve timing adjusting device according to a first embodiment of the present invention.
In the driving force transmission system, as shown in FIG. 3, a gear 3 fixed to a crankshaft 2 as a driving shaft of the engine 1 and gears 6 and 11 fixed to camshafts 4 and 5 as driven shafts. The chain 7 is wound around and the driving force is transmitted from the crankshaft 2 to the camshafts 4 and 5. One camshaft 4 drives the intake valve 8 to open and close, and the other camshaft 5 drives the exhaust valve 9 to open and close. The valve timing adjusting device 10 of this embodiment is a hydraulic control type that uses hydraulic oil as a working fluid, and connects the gear 113 to the chain 7 and the vane rotor to the camshaft 4 to adjust the opening / closing timing of the intake valve 8.

As shown in FIGS. 1 and 2, the valve timing adjusting device 10 includes a housing 12, a vane rotor 20, and the like.
The housing 12 has a cylindrical peripheral wall 13, four shoes 14 to 17 projecting radially inward from the peripheral wall 13, a front plate 18, and a rear plate 11. A front plate 18 is provided on one side of the peripheral wall 13 in the axial direction, and a rear plate 11 is provided on the other side of the peripheral wall 13 in the axial direction.
The shoes 14 to 17 are formed in a substantially trapezoidal shape and are provided at substantially equal intervals in the circumferential direction of the peripheral wall 13. Four pressure chambers 50 are formed in the gap between the shoes adjacent in the circumferential direction.
The front plate 18 has an axial hole 181 through which the camshaft 4 is passed in the axial direction.
The rear plate 11 has a gear 113 on the radially outer side. The rear plate 11 has an axial hole 111 through which the camshaft 4 is passed in the axial direction. The front plate 18 and the rear plate 11 can rotate relative to the camshaft 4.

The vane rotor 20 is provided substantially coaxially with the housing 12 and is accommodated inside the housing 12. The vane rotor 20 includes a substantially cylindrical boss portion 21 and four vanes 24 to 27 protruding from the boss portion 21 in the radially outward direction.
The boss portion 21 has an axial hole 211 through which the camshaft 4 passes in the axial direction. The boss portion 21 and the camshaft 4 are fixed by press fitting, welding, bolts or the like. Thereby, the vane rotor 20 rotates with the camshaft 4.
The vanes 24 to 27 partition the pressure chambers 50 into retard chambers 51 to 54 and advance chambers 55 to 58, respectively.

  The outer diameter of the boss 21 is slightly smaller than the inner diameter of the shoes 14-17. For this reason, the slidable contact surfaces 41 to 44 on the inner diameter side of the shoes 14 to 17 and the outer wall on the outer diameter side of the boss portion 21 are slidably contacted. The sliding contact surfaces 41 to 44 of the shoes 14 to 17 and the outer wall of the boss portion 21 are formed on the other side of the retarding chambers 51 to 54 formed on one side in the circumferential direction of the shoes 14 to 17. The leakage of hydraulic fluid between the advance chambers 55 to 58 is suppressed.

  The outer diameters of the vanes 24 to 27 are formed slightly smaller than the inner diameter of the peripheral wall 13 of the housing 12. The seal member 28 is formed of, for example, resin and is fitted to the outer walls of the vanes 24 to 27 in the radially outward direction. The seal member 28 is pressed against the peripheral wall 13 by the elastic force of a leaf spring (not shown). The seal member 28 suppresses the leakage of hydraulic oil between the retard chambers 51 to 54 and the advance chambers 55 to 58 via the space between the radial outer walls of the vanes 24 to 27 and the peripheral wall 13.

  A stopper piston (not shown) is provided in the hole 29 provided in the vane 27. The stopper piston regulates relative rotation between the housing 12 and the vane rotor 20 by fitting into a fitting ring (not shown) provided on the rear plate. The description of the configuration of the stopper piston is omitted.

The valve timing adjusting device 10 of this embodiment rotates clockwise as viewed from the direction of arrow A shown in FIG. This rotation direction is defined as an advance direction.
The arrows representing the advance angle and retard angle shown in FIG. 1 represent the advance direction and the retard direction of the vane rotor 20 with respect to the housing 12.
The housing 12 and the vane rotor 20 are provided so as to be relatively rotatable. That is, when the hydraulic pressure supplied to each of the retard chambers 51 to 54 acts on the inner wall of the housing 12 and the outer wall of the vane rotor 20, the vane rotor 20 rotates relative to the housing 12 in the retard direction. On the other hand, when the hydraulic pressure supplied to each advance chamber 55 to 58 acts on the inner wall of the housing 12 and the outer wall of the vane rotor 20, the vane rotor 20 rotates relative to the housing 12 in the advance direction. FIG. 1 shows the phase conversion angle θ1 of the valve timing adjusting device 10 by such an operation.
FIG. 1 shows a state in which the vane rotor 20 is phase-controlled at the most advanced position with respect to the housing 12.

Next, the hydraulic pressure supply passage of the valve timing adjusting device 10 will be described.
The camshaft 4 and the boss portion 21 are formed with retard passages 31 to 34 and advance passages 35 to 38 extending in the radial direction. When the vane rotor 20 is phase-controlled at the most advanced position with respect to the housing 12, the retard passages 31 to 34 are respectively provided on the retard chambers 51 to 54 side of the sliding contact surfaces 41 to 44. The opening is located. On the other hand, when the vane rotor 20 is phase-controlled to the most retarded position with respect to the housing 12, the advance passages 35 to 38 are respectively connected to the advance chambers 55 to 58 of the sliding contact surfaces 41 to 44. It is formed so that openings of ~ 38 are located.

  The slidable contact surfaces 41 to 44 are formed with retarded grooves 61 to 64 and advanced grooves 65 to 68, respectively. The retard grooves 61 to 64 are formed so as to communicate the openings of the retard passages 31 to 34 and the retard chambers 51 to 54 when the phase of the vane rotor 20 is controlled to the most advanced position with respect to the housing 12. Has been. On the other hand, the advance grooves 65 to 68 communicate the openings of the advance passages 35 to 38 and the advance chambers 55 to 58 when the vane rotor 20 is phase-controlled at the most retarded position with respect to the housing 12. Is formed.

The retard groove and the advance groove and the sliding contact surface on which these are formed will be described in more detail with reference to FIGS. FIG. 4 shows only the peripheral wall 13 and the shoes 14 to 17 of the valve timing adjusting device 10. FIG. 5 is a view in the direction of the arrow V in FIG. That is, FIG. 5 shows the shoe 14 and the peripheral wall 13 in the vicinity thereof.
In FIG. 5, the position of the opening of the retard passage 31 when the vane rotor 20 is phase-controlled to the most advanced position with respect to the housing 12 and the phase of the vane rotor 20 to the most retarded position with respect to the housing 12 are illustrated. The position of the opening of the advance passage 35 when being controlled is indicated by a broken line.
The retard groove 61 is provided on one side of the sliding contact surface 41 in the axial direction, and the advance groove 65 is provided on the other side of the sliding contact surface 41 in the axial direction. Specifically, the retard groove 61 is open to the wall surface 181 of the shoe 14 on the front plate 18 side and the wall surface 145 of the shoe 14 on the retard chamber 51 side. On the other hand, the advance groove 65 opens to the wall surface 111 of the shoe 14 on the rear plate 11 side and the wall surface 146 of the shoe 14 on the advance chamber 55 side. Thus, the retard groove 61 and the advance groove 65 are diagonally provided on the sliding contact surface 41. For this reason, the diagonal distance L2 between the retard groove 61 and the advance groove 65 becomes longer. Further, by providing the retard groove 61 and the advance groove 65 diagonally on the sliding contact surface 41, the circumferential distance L 5 between the retard groove 61 and the advance groove 65, It is possible to shorten the circumferential distance L1. The retard groove 61 and the advance groove 65 may overlap with each other when viewed from the axial direction (the direction of arrow B in FIG. 5).
The distance L3 between the retard groove 61 and the advance chamber 55 side of the shoe 14, the distance L4 between the advance groove 65 and the retard chamber 51 side of the shoe 14, the circumferential distance L1 of the sliding contact surface 41, and the retard angle The diagonal distance L <b> 2 between the groove 61 and the advance groove 65 is formed at a distance that can ensure the sealing performance of the hydraulic oil by the sliding contact surface 41 and the outer wall of the boss portion 21. With this configuration, hydraulic oil leakage between the retard chamber 51 formed on one side of the shoe 14 in the circumferential direction and the advance chamber 55 formed on the other side is suppressed.

Next, the operation of the valve timing adjusting device 10 will be described.
<When starting the engine>
When the engine 1 is stopped, the stopper piston is fitted in the fitting ring. In the state immediately after starting the engine 1, the hydraulic oil is not sufficiently supplied from the hydraulic pump 90 to the retard chambers 51 to 54 and the advance chambers 55 to 58. For this reason, the stopper piston maintains a state of being fitted to the fitting ring, and the camshaft 4 is held at the most retarded position with respect to the crankshaft 2. As a result, the generation of hitting sound due to the collision between the housing 12 and the vane rotor 20 due to the torque fluctuation received by the camshaft 4 until the hydraulic oil is supplied to the pressure chambers 50 is prevented.

<After starting the engine>
When the hydraulic oil is supplied from the hydraulic pump 90 after the engine is started, the stopper piston comes out of the fitting ring, and the relative rotation of the vane rotor 20 with respect to the housing 12 is allowed. And the phase difference of the camshaft 4 with respect to the crankshaft 2 can be adjusted by controlling the hydraulic pressure of the retarding chambers 51-54 and the advance chambers 55-58.

<Advance angle operation>
When the valve timing adjusting device 10 is advanced, the electronic control device (hereinafter referred to as “ECU”) 91 controls the drive current supplied to the switching valve 92. The switching valve 92 connects the hydraulic pump 90 and the advance passage 93 and connects the retard passage 94 and the oil pan 95. The hydraulic oil discharged from the hydraulic pump 90 is supplied to the advance chambers 55 to 58 via the advance passages 93, 35 to 38 and the advance grooves 65 to 68. On the other hand, the hydraulic oil in the retard chambers 51 to 54 is discharged to the oil pan 95 through the retard grooves 61 to 64 and the retard passages 31 to 34 and 94. The hydraulic pressure in the advance chambers 55 to 58 acts on the housing 12 and the vanes 24 to 27 to generate torque that urges the vane rotor 20 in the advance direction. As a result, the vane rotor 20 rotates in the advance direction with respect to the housing 12.

<At retarded angle operation>
When the valve timing adjusting device 10 is retarded, the ECU 91 controls the drive current supplied to the switching valve 92. The switching valve 92 connects the hydraulic pump 90 and the retard passage 94, and connects the advance passage 93 and the oil pan 95. The hydraulic oil discharged from the hydraulic pump 90 is supplied to the retard chambers 51 to 54 via the retard passages 94, 31 to 34 and the retard grooves 61 to 64. On the other hand, the hydraulic oil in the advance chambers 55 to 58 is discharged to the oil pan 95 via the advance passages 35 to 38 and 93 and the advance grooves 65 to 68. The hydraulic pressure of the retard chambers 51 to 54 acts on the housing 12 and the vanes 24 to 27 to generate torque that urges the vane rotor 20 in the retard direction. Thereby, the vane rotor 20 rotates in the retard direction with respect to the housing 12.

<Intermediate holding operation>
When the vane rotor 20 reaches the target phase, the ECU 91 controls the duty ratio of the drive current supplied to the switching valve 92. The switching valve 92 cuts off the connection between the hydraulic pump 90 and the retard passage 94 and the advance passage 93, and the hydraulic oil is discharged from the retard chambers 51 to 54 and the advance chambers 55 to 58 to the oil pan 95. To regulate that. For this reason, the vane rotor 20 is held at the target phase.

<Operation when the engine is stopped>
When the engine stop is instructed during the operation of the valve timing adjusting device 10, the vane rotor 20 rotates in the retard direction with respect to the housing 12 by the same operation as that in the retard operation, and rotates at the most retarded position. Stop. In this state, the ECU 91 stops the operation of the hydraulic pump 90 and connects the retard passage 94 and the oil pan 95 by the switching valve 92. Thereby, the stopper piston is fitted to the fitting ring.

(Comparative example)
Here, FIG. 12 shows an enlarged view of the main part of the peripheral wall and the shoe of the valve timing adjusting device of the comparative example. Note that, in this comparative example and a plurality of embodiments described later, substantially the same configurations as those of the above-described first embodiment are denoted by the same reference numerals, and description thereof is omitted.
In the comparative example, the retard groove 611 and the advance groove 651 are extended in the axial direction of the sliding contact surface 411, and the retard groove 611 and the advance groove 651 are formed from the front plate 181 side to the rear plate 111 side. In FIG. 12, in order to clarify the positions of the retard groove 611 and the advance groove 651, hatched portions are shown in the portions.
In the comparative example, the distance L9 between the retard groove 611 and the advance groove 651 is formed to be a distance that can ensure sealing performance. For this reason, the distance L10 in the circumferential direction of the shoe 141 is longer than the distance L1 in the circumferential direction of the shoe 14 of the first embodiment.

(Effect of 1st Embodiment)
In the first embodiment, the retard grooves 61 to 64 and the advance grooves 65 to 68 are provided diagonally on the sliding contact surfaces 41 to 44. As described above, by providing the distance L2 between the retard grooves 61 to 64 and the advance grooves 65 to 68 far, the sealing performance of the hydraulic oil by the sliding contact surfaces 41 to 44 and the outer wall of the boss portion 21 is improved. Can do.
In the valve timing adjusting device 10 of the first embodiment, the retard groove 61 and the advance groove 65 are diagonally provided on the sliding contact surface 41, so that the sealing performance of the comparative example is substantially the same (the comparative example). L9 and L2, L3, and L4 of the first embodiment are substantially the same distance), the circumferential distance L5 between the retard groove 61 and the advance groove 65 is shortened, and the circumferential distance L1 of the shoe 14 is decreased. It becomes possible to form. Accordingly, the pressure chamber 50 can be formed larger in the circumferential direction, and the phase conversion angle θ1 can be increased.

Further, for example, if the distance L1 in the circumferential direction of the shoe 14 is formed short and the outer diameters of the housing 12 and the vane rotor 20 are formed small without changing the phase conversion angle θ1 of the first embodiment, the valve timing adjusting device The physique can be reduced in the radial direction.
Further, for example, the diagonal distance L2 between the retard groove 61 and the advance groove 65 of the first embodiment can be used to maintain the sealing performance of the hydraulic oil by the sliding contact surface 41 and the outer wall of the boss portion 21. If it is formed as small as possible, the size of the valve timing adjusting device can be reduced in the axial direction.

  Further, for example, without changing the phase conversion angle θ1 of the first embodiment and without reducing the physique, the valve timing can be adjusted by increasing the number of vanes by forming the shoe 14 smaller in the circumferential direction. The device can increase torque.

(Second Embodiment)
FIG. 6 shows only the shoe of the valve timing adjusting device according to the second embodiment of the present invention and the peripheral wall in the vicinity thereof. The second embodiment is a modification of the first embodiment.
In this embodiment, the retard groove 610 and the advance groove 650 extend in the circumferential direction without extending the sliding contact surface 41 in the axial direction. Specifically, the retard groove 610 does not open on the wall surface 181 of the shoe 14 on the front plate 18 side but opens on the wall surface 145 of the shoe 14 on the retard chamber 51 side. On the other hand, the advance groove 65 does not open on the wall surface 111 on the rear plate 11 side of the shoe 14 but opens on the wall surface 146 on the retard chamber 55 side of the shoe 14.
In the present embodiment, the retard groove 610 and the advance groove 650 are formed by cutting the sliding contact surface 41 in the circumferential direction by, for example, milling. By forming the retard groove 610 and the advance groove 650 in this way, the number of processing steps can be reduced.

(Third embodiment)
A valve timing adjusting device 103 according to a third embodiment of the present invention is shown in FIGS. In the present embodiment, the retard grooves 71 to 74 and the advance grooves 75 to 78 are formed on the outer wall of the boss portion 21.

9 shows only the vane rotor 20 of the valve timing adjusting device 103, and FIG. 10 shows an arrow view in the X direction shown in FIG. FIG. 10 shows the outer wall of the boss portion 21 between the two vanes 25 and 26 and the vicinity thereof.
In FIG. 10, the positions of both ends 431 and 432 of the sliding contact surface 43 of the shoe 16 when the vane rotor 20 is phase-controlled at the most advanced angle position with respect to the housing 12 are indicated by broken lines.

The retard groove 73 is provided in one of the axial directions of the outer wall of the boss portion 21, and the advance groove 77 is provided in the other of the outer walls of the boss portion 21 in the axial direction. Specifically, the retarding groove 73 opens to the wall surface 182 of the boss portion 21 on the front plate 18 side, and extends to the boundary line 250 between the boss portion 21 and one vane 25. The advance groove 77 opens on the wall surface 112 of the boss portion 21 on the rear plate 11 side and extends to the boundary line 260 between the boss portion 21 and the other vane 26. Thus, the retard groove 73 and the advance groove 77 are diagonally provided on the outer wall of the boss portion 21.
Here, if the retard groove and the advance groove are extended in the axial direction of the boss part, and the retard groove and the advance groove are formed from the front plate side to the rear plate side, the phase is controlled to the most advanced position. The distance in the circumferential direction between the end of the slidable contact surface of the shoe and the retard groove becomes closer. For this reason, the area of a sliding contact surface becomes small and a sealing performance falls. Compared with the circumferential distance between the end of the sliding surface of the shoe and the retarding groove in this case, the valve timing adjusting device 103 according to the third embodiment has the retarding groove 73 and the end of the sliding surface 43. The diagonal distance L7 from 432 can be increased. With this configuration, the area of the sliding contact surface 43 is increased, and the retard angle chamber 53 formed between one vane 25 and the shoe 16 and the advance angle formed between the other vane 26 and the shoe 16. The leakage of hydraulic oil between the chamber 57 can be suppressed.

  In the present embodiment, the slidable contact surfaces 41 to 44 and the boss portions are provided by diagonally providing the retard grooves 71 to 74 and the advance grooves 75 to 78 on the outer wall of the boss portion 21 between the vanes 14 to 17. The sealing performance by the outer wall 21 is improved. Further, the valve timing adjusting device 103 according to the present embodiment is configured so that the diagonal distance L7 between the retarding groove 73 and the end of the sliding contact surface 41 is equal to the retarding groove 61 and the advancement groove 65 according to the first embodiment described above. The distance L2 can be longer than the diagonal distance L2. For this reason, the valve timing adjusting device 103 of the present embodiment further improves the sealing performance between the sliding contact surfaces 41 to 44 and the outer wall of the boss portion 21, expands the phase conversion angle, and makes the physique smaller than the first embodiment. Can be

(Fourth embodiment)
FIG. 11 shows only the vane rotor of the valve timing adjusting apparatus according to the fourth embodiment of the present invention. The fourth embodiment is a modification of the third embodiment.
In this embodiment, the retard groove 730 and the advance groove 770 extend in the circumferential direction without extending the outer wall of the boss portion 21 in the axial direction. Specifically, the retard groove 730 does not open on the wall surface 182 of the boss portion 21 on the front plate 18 side, and extends to the vicinity of the boundary line 250 between the boss portion 21 and one vane 25. On the other hand, the advance groove 770 extends to the vicinity of the boundary line 260 between the boss portion 21 and the other vane 26 without opening in the wall surface 112 of the boss portion 21 on the rear plate 11 side.
In the present embodiment, the retard groove 730 and the advance groove 770 are formed by cutting the outer wall of the boss portion 21 in the circumferential direction by, for example, milling. By forming the retard groove 730 and the advance groove 770 in this way, the number of processing steps can be reduced.

(Other embodiments)
In the above embodiment, the valve timing adjusting device that controls the intake valve of the internal combustion engine has been described. On the other hand, you may apply this invention to the valve timing adjustment apparatus which controls the exhaust valve of an internal combustion engine.
In the said embodiment, the surrounding wall 13 and the shoes 14-17 of the housing 12, the front plate 18, and the rear plate 11 were comprised separately. On the other hand, in the present invention, the peripheral wall, the shoe, the front plate, and the rear plate may be integrally formed.
Further, in the above embodiment, the gear 113 is provided outside the diameter of the rear plate 11. In contrast, in the present invention, the gear may be provided outside the diameter of the peripheral wall or the front plate.
Thus, the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the invention.

  4: camshaft (driven shaft), 10, 103: valve timing adjusting device, 11: rear plate, 12: housing, 13: peripheral wall, 14-17: shoe, 18: front plate, 20: vane rotor, 21: boss part 24 to 27: vane, 35 to 38 advance passage, 31 to 34: retard passage, 41 to 44: sliding contact surface, 50: pressure chamber, 51 to 54: retard chamber, 55 to 58: advance chamber 61-64, 71-74, 610, 730: retard groove, 65-68, 75-78, 650, 770: advance groove

Claims (4)

By changing the phase of the drive shaft of the internal combustion engine and the driven shaft that is rotationally driven by the drive force of the drive shaft to open and close the intake valve and the exhaust valve, the opening / closing timing of at least one of the intake valve and the exhaust valve is adjusted. A valve timing adjusting device for adjusting,
A cylindrical peripheral wall, a shoe protruding radially inward from the peripheral wall, a front plate provided on one axial side of the peripheral wall, and a rear plate provided on the other axial side of the peripheral wall, the drive shaft or the A housing that rotates with one of the driven shafts;
A substantially cylindrical boss portion that is provided substantially coaxially with the housing and slidably contacts a slidable contact surface on the radially inner side of the shoe, and a pressure that protrudes radially outward from the boss portion and is formed on both sides in the circumferential direction of the shoe. A vane that partitions the chamber into an advance chamber and a retard chamber, and rotates with the other of the drive shaft or the driven shaft, and the pressure of the working fluid supplied to the advance chamber or the retard chamber A vane rotor that rotates relative to the housing,
When the vane rotor is at the most retarded position with respect to the housing, the boss portion has an advance passage in which an opening is located on the advance chamber side of the sliding contact surface, and the vane rotor is at the most with respect to the housing. A retard passage having an opening on the retard chamber side of the sliding contact surface when in the advance position;
When the vane rotor is at the most retarded position with respect to the housing, the shoe has an advance groove that communicates the opening of the advance passage and the advance chamber, and the vane rotor is most advanced with respect to the housing. A retard groove that communicates the opening of the retard passage and the retard chamber when in an angular position;
The valve is characterized in that one of the advance groove and the retard groove is provided on the rear plate side of the sliding contact surface, and the other groove is provided on the front plate side of the sliding contact surface. Timing adjustment device.   The valve timing adjusting device according to claim 1, wherein the advance groove and the retard groove extend in the circumferential direction without extending the sliding contact surface in the axial direction. Instead of the shoe having the advance groove and the retard groove, the boss part has the advance groove and the retard groove on the outer wall thereof,
One of the advance angle groove and the retard angle groove is provided on the rear plate side of the outer wall of the boss portion, and the other groove is provided on the front plate side of the outer wall of the boss portion. The valve timing adjusting device according to claim 1.   The valve timing adjusting device according to claim 3, wherein the advance groove and the retard groove extend in the circumferential direction without extending the outer wall of the boss portion in the axial direction.

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