JP2009150357A - Valve timing adjusting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly-responsive valve timing adjusting device. <P>SOLUTION: Open-to-air drain passages 82, 83 have fluid reservoir portions 82a, 83a for accumulating hydraulic fluid. A spool 130 forms a lead connection passage 220 connecting a lead output passage 75 and the lead fluid reservoir portion 82a in a lead position and a lag connection passage 240 connecting a lag output passage 79 and the lag fluid reservoir portion 83a in a lag position, and incorporates: a lead check valve 210 which opens when the lead output passage 75 side of the lead connection passage 220 becomes lower in pressure than the lead fluid reservoir portion 82 side in the lead position and closes when the lead output passage 75 side of the lead connection passage 220 becomes higher in pressure than the lead fluid reservoir portion 82 side; and a lag check valve 230 which opens when the lag output passage 79 side of the lag connection passage 240 becomes lower in pressure than the lag fluid reservoir portion 83a side in the lag position and closes when the lag output passage 79 side of the lag connection passage 240 becomes higher in pressure than the lag fluid reservoir portion 83a side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a valve timing adjusting device that adjusts the valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine.

  2. Description of the Related Art Conventionally, a fluid-driven valve timing adjusting device including a housing as a driving rotating body that rotates in conjunction with a crankshaft and a vane rotor as a driven rotating body that rotates in conjunction with a camshaft has been widely used. As a kind of such valve timing adjusting device, Patent Document 1 discloses that a camshaft is connected to a crankshaft by supplying a working fluid to an advance chamber or a retard chamber formed in a rotational direction between a housing and a vane rotor. An apparatus for adjusting the valve timing by driving to the advance side or the retard side is disclosed.

  Specifically, in the device disclosed in Patent Document 1, an input passage through which a working fluid is input from a pump as a fluid input source, an advance output passage and a retard angle for outputting the working fluid to an advance chamber and a retard chamber. A spool valve is disposed between the output passage and the advance drain passage and the retard drain passage through which the working fluid is discharged.

  When the valve timing is advanced by driving the camshaft toward the advance side with respect to the crankshaft, the spool passage of the spool valve connects the input passage to the advance output passage and the retard output passage. Connect the retarded drain passage. As a result, the output fluid from the input passage to the advance output passage is supplied to the advance chamber, and the internal fluid in the retard chamber is discharged from the retard output passage to the retard drain passage. Can be driven quickly.

On the other hand, when the valve timing is retarded by driving the camshaft to the retard side with respect to the crankshaft, the spool passage of the spool valve connects the input passage to the retard output passage and the advance output passage Is connected to the advance drain passage. As a result, the output fluid from the input passage to the retard output passage is supplied to the retard chamber, and the internal fluid in the advance chamber is discharged from the advance output passage to the advance drain passage. Thus, it is possible to drive quickly.
European Patent No. 1596041

  Now, as disclosed in Patent Document 1, in the valve timing adjusting device, a fluctuating torque that alternately biases the cam shaft to the advance side and the retard side with respect to the crankshaft acts. Therefore, for example, when the camshaft is driven to the advance side with respect to the crankshaft, a variable torque that biases the camshaft acts on the advance side, and the advance chamber that instantaneously expands the volume, There is a risk that the working fluid may not be supplied in time. If the supply of the working fluid is not in time, the internal pressure of the advance chamber becomes negative as shown in FIG. 10, so that air is sucked into the advance chamber through the device clearance. In this state, when the direction of action of the variable torque is reversed, the air sucked into the advance chamber is crushed by the working fluid or pushed out through the device clearance until the internal pressure of the advance chamber returns to atmospheric pressure. The vane rotor rotates the cam shaft relative to the retard side with respect to the crankshaft. Accordingly, although it is desired to advance the phase of the camshaft relative to the crankshaft, the phase returns to the retard side as shown in FIG. 10, so that the advancement responsiveness cannot be improved. Such a decrease in responsiveness also occurs when the camshaft is driven to the retard angle side with respect to the crankshaft. Therefore, it is desirable to deal with both the advance angle side drive and the retard angle side drive. ing.

  The present invention has been made in view of the problems of the prior art described above, and an object of the present invention is to provide a valve timing adjusting device with high responsiveness.

  The invention according to claim 1 is a valve timing adjusting device that adjusts the valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine, and that rotates in conjunction with the crankshaft. The cam and the camshaft rotate in conjunction with the camshaft to form an advance chamber and a retard chamber in the rotational direction between the drive rotor and the working fluid supplied to the advance chamber or retard chamber. A driven rotor that drives the shaft to the advance side or retard side with respect to the crankshaft, an input passage through which the working fluid is input from the fluid input source, and an advance output that outputs the working fluid to the advance chamber and the retard chamber A passage forming body that forms a passage and a retard output passage, an advance drain passage and a retard drain passage through which the working fluid is discharged, a reciprocating spool, and the camshaft on the advance side with respect to the crankshaft When driving, sp By moving the valve to the advance angle position, the input passage is connected to the advance output passage and the retard drain passage is connected to the retard output passage, and the camshaft is driven to the retard side with respect to the crankshaft. And a spool valve that connects the input passage to the retard output passage and connects the advance drain passage to the advance output passage by moving the spool to the retard position. In the apparatus, the advance drain passage and the retard drain passage that are opened to the atmosphere have an advance fluid reservoir portion and a retard fluid reservoir portion that accumulate the working fluid discharged to each, and the spool is an advance position of the spool. Between the advance output passage and the advance fluid reservoir, and between the retard output passage and the retard fluid reservoir under the state of movement to the retard position of the spool. Connecting retarded connection In the advanced angle connecting passage, the advanced angle output passage side of the advanced angle connecting passage is lower in pressure than the advanced angle fluid reservoir portion side, and the open angle advanced angle connecting passage is opened. An advance check valve that closes when the advance output passage side is higher than the advance fluid reservoir side, and the retard output passage side is delayed in the retard connection passage when the spool is moved to the retard position. Built-in retard check valve that opens when the pressure is lower than the angle fluid reservoir side and closes when the retard output passage side becomes higher than the retard fluid reservoir side in the retard connection passage It is characterized by doing.

  According to the first aspect of the present invention, when the camshaft is driven to the advance side with respect to the crankshaft, the input passage is connected to the advance output passage by moving the spool to the advance position. A retard drain passage is connected to the retard output passage. Therefore, the working fluid input to the input passage from the fluid input source is output from the advance output passage and supplied to the advance chamber, and the working fluid in the retard chamber passes through the retard output passage to the retard drain passage. Will be discharged.

  In such a state of movement of the spool to the advance position, the advance output passage and the advance fluid reservoir of the advance drain passage are connected by the advance connection passage. Here, the advance angle output passage is for outputting the working fluid to the advance angle chamber, and the advance angle fluid reservoir is for collecting the working fluid discharged to the advance drain passage in the atmosphere open state. It is. Therefore, in the state where the spool is moved to the advance position, if the volume of the advance chamber is increased by the action of the variable torque that urges the cam shaft toward the advance side with respect to the crankshaft, the internal pressure of the advance chamber becomes negative. In the advance connection passage, the advance output passage side has a negative pressure lower than that of the advance fluid reservoir portion at atmospheric pressure, thereby opening the advance check valve. As a result, the working fluid stored in the advance fluid reservoir is sucked into the advance chamber of negative pressure through the advance connection passage and the advance output passage, and therefore, through the device clearance to the advance chamber. The amount of air suction can be reduced. According to this, since the supply amount of the working fluid to the advance chamber with the increased volume is ensured, even if the direction of the variable torque that biases the camshaft to the advance side is reversed, the retard side with respect to the crankshaft Thus, the rotation of the driven rotating body that drives the camshaft can be suppressed.

  Further, in the state of movement of the spool to the advance angle position, when the advance chamber is compressed by the action of the variable torque that urges the cam shaft toward the retard angle side, the working fluid whose pressure has increased to the positive pressure side advances. It flows into the advance output passage from the corner chamber. At this time, in the advance connection passage that connects the advance output passage and the advance fluid reservoir, the advance output passage side that is positive pressure has a higher pressure than the advance fluid reservoir side of the atmospheric pressure, so that the advance proceeds. Angular check valve closes. Therefore, the fluid that flows into the advance output passage is discharged from the advance connection passage to the advance drain passage by the advance check valve. Accordingly, it is possible to prevent the working fluid in the advance chamber from flowing into the advance drain passage through the advance output passage and the advance connection passage.

  According to the above, when the valve timing is advanced by driving the camshaft to the advance side with respect to the crankshaft, a sufficient amount of working fluid is supplied to the advance chamber and the working fluid is supplied from the retard chamber. It is possible to improve the advance angle responsiveness by discharging.

  On the other hand, according to the first aspect of the present invention, when the camshaft is driven to the retard side with respect to the crankshaft, the spool is moved to the retard position, so that the input passage is connected to the retard output passage. An advance drain passage is connected to the advance output passage. Therefore, the working fluid input from the fluid input source to the input passage is output from the retard output passage and supplied to the retard chamber, and the working fluid in the advance chamber passes through the advance output passage to the advance drain passage. Will be discharged.

  In such a state that the spool is moved to the retard position, the retard output passage and the retard fluid reservoir of the retard drain passage are connected by the retard connection passage. Here, the retarded angle output passage is for outputting the working fluid to the retarded angle chamber, and the retarded angle fluid reservoir is for accumulating the working fluid discharged into the retarded drain passage in the atmosphere open state. It is. Therefore, in the state where the spool is moved to the retard angle position, if the retard chamber is expanded in volume by the action of the variable torque that urges the cam shaft toward the retard angle, the internal pressure of the retard chamber becomes negative. In the retarded connection passage, the retarded output passage side has a negative pressure lower than that of the retarded fluid reservoir portion at atmospheric pressure, thereby opening the retarded check valve. As a result, the working fluid accumulated in the retarded angle fluid reservoir is sucked into the retarded pressure chamber of the negative pressure through the retarded angle connecting passage and the retarded output passage, and therefore through the device clearance to the retarded angle chamber. The amount of air suction can be reduced. According to this, since the supply amount of the working fluid to the retarded chamber with the increased volume is ensured, even if the direction of the variable torque that biases the camshaft to the retarded side is reversed, the advanced side with respect to the crankshaft Thus, the rotation of the driven rotating body that drives the camshaft can be suppressed.

  Further, in the state of movement of the spool to the retarded position, when the retarded chamber is compressed by the action of the variable torque that biases the camshaft toward the advance side with respect to the crankshaft, the working fluid whose pressure has increased to the positive pressure side is retarded. It flows into the retarded angle output passage from the corner chamber. At this time, in the retarded connection passage connecting the retarded output passage and the retarded fluid reservoir, the retarded output passage side that is positive pressure has a higher pressure than the retarded fluid reservoir side of the atmospheric pressure, so that Angular check valve closes. Therefore, it is possible to restrict the inflow fluid to the retard output passage from being discharged from the retard connection passage to the retard drain passage by the retard check valve. Accordingly, it is possible to prevent the working fluid in the retard chamber from flowing into the retard drain passage through the retard output passage and the retard connection passage.

  According to the above, when the camshaft is driven to the retard side with respect to the crankshaft to retard the valve timing, the working fluid is supplied from the advance chamber while supplying a sufficient amount of working fluid to the retard chamber. It is possible to increase the retardation responsiveness by discharging.

  According to the second aspect of the present invention, the advance fluid reservoir and the retard fluid reservoir are opened upward in the passage forming body, and the advance drain passage and the retard drain passage are opened to the atmosphere in the opening. The As described above, according to the advance fluid reservoir and the retard fluid reservoir that open upward in the passage forming body, not only can the working fluid discharged to the corresponding drain passages be reliably stored, respectively. The opening can be easily opened to the atmosphere, and the pressure of the accumulated working fluid can be maintained at atmospheric pressure. Therefore, the functions of the advance angle check valve and the retard angle check valve can be exhibited properly in a timely manner, and both the advance angle responsiveness and the retard angle responsiveness can be enhanced.

  According to the third aspect of the present invention, the volume of the advance fluid reservoir is increased by the variable torque that urges the cam shaft toward the advance side when the cam shaft is driven toward the advance side relative to the crank shaft. The volume of the retarding fluid reservoir is set by the variable torque that urges the camshaft to the retard side when the camshaft is driven to the retard side with respect to the crankshaft. It is set to be equal to or larger than the volume expansion amount of the retarded angle chamber in which the volume expands.

  Here, in the state of movement of the spool to the retard position, the working fluid discharged to the advance drain passage can be filled into the advance fluid reservoir. Therefore, according to the third aspect of the present invention, the advance chamber is expanded in volume and the advance check valve is opened while the spool is moved to the advance position, so that the advance check valve is opened. Even if the filled working fluid is sucked into the advance chamber, the advance fluid reservoir having a volume larger than the volume expansion amount can be suppressed from being emptied. According to this, it is possible to avoid a situation in which the air that has flowed into the fluid reservoir portion is sucked into the advance chamber by emptying the advance fluid reservoir portion in the atmosphere open state, and to ensure high advance responsiveness. be able to.

  On the other hand, when the spool is in the advanced position, the working fluid discharged to the retarded drain passage can be filled into the retarded fluid reservoir. Therefore, according to the third aspect of the present invention, the retard chamber is expanded in volume and the retard check valve is opened while the spool is moved to the retard position. Even if the filled working fluid is sucked into the retard chamber, it is possible to prevent the retard fluid reservoir having a volume larger than the volume expansion amount from being emptied. According to this, it is possible to avoid a situation where air that has flowed into the fluid reservoir is sucked into the retard chamber due to emptying of the retarded fluid reservoir in the open state due to suction of the working fluid, and high retard Responsiveness can be ensured.

  According to the fourth aspect of the present invention, the valve is opened when the fluid input source side has a higher pressure than the spool valve side in the input passage, and the valve is closed when the spool valve side has a higher pressure than the fluid input source side in the input passage. An input check valve is provided.

  In such a fourth aspect of the invention, the compressed working fluid in the advance chamber is transferred to the input passage connected to the advance output passage via the spool valve while the spool is moved to the advance position. Even if it flows in, the input check valve closes when the spool valve side in the input passage becomes higher in pressure than the fluid input source side. According to this, since it is possible to restrict the working fluid from flowing out of the advance chamber and flowing back to the fluid input source side through the input passage, a sufficient amount of working fluid is supplied to the advance chamber and the advance angle response is achieved. Can be increased.

  On the other hand, when the spool is moved to the retard position, the compressed working fluid in the retard chamber flows into the input passage connected to the retard output passage via the spool valve. When the valve side is at a higher pressure than the fluid input source side, the input check valve is closed. According to this, since it is possible to restrict the working fluid from flowing out of the retarding chamber and flowing back to the fluid input source side through the input passage, a sufficient amount of working fluid is supplied to the retarding chamber to retard the retarding response. Can be increased.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example in which a valve timing adjusting device 1 according to an embodiment of the present invention is applied to an internal combustion engine of a vehicle. The valve timing adjusting device 1 is a fluid drive type that uses hydraulic oil as the “working fluid”, and adjusts the valve timing of the intake valve as the “valve”.

(Basic configuration)
Hereinafter, a basic configuration of the valve timing adjusting device 1 will be described. The valve timing adjusting device 1 is installed in a driving force transmission system that transmits a driving force of a crankshaft (not shown) of an internal combustion engine to a camshaft 2 of the internal combustion engine, and is driven by hydraulic oil. And a control unit 30 that controls the supply of hydraulic oil to 10.

(Drive part)
As shown in FIGS. 1 and 2, a housing 11 as a “drive rotator” in the drive unit 10 includes a shoe housing 12 and a sprocket 13.

  The shoe housing 12 includes a bottomed cylindrical tube portion 12a and a plurality of shoes 12b, 12c, and 12d as partition portions.

  Each of the shoes 12b to 12d protrudes radially inward from a portion that is substantially equidistant in the rotation direction in the cylindrical portion 12a. The protruding side end surfaces of the shoes 12b to 12d have an arcuate concave shape when viewed from the direction perpendicular to the plane of FIG. 2 and are in sliding contact with the outer peripheral wall surface of the boss portion 14a of the vane rotor 14. A storage chamber 50 is formed between the shoes 12b to 12d adjacent in the rotation direction.

  The sprocket 13 has an annular plate shape and is coaxially mounted on the opening side of the cylindrical portion 12a. The sprocket 13 is connected to the crankshaft via a timing chain (not shown). Thus, during operation of the internal combustion engine, the driving force is transmitted from the crankshaft to the sprocket 13, whereby the housing 11 rotates in the clockwise direction in FIG. 2 in conjunction with the crankshaft.

  The vane rotor 14 as a “driven rotor” is accommodated coaxially in the housing 11 and is in sliding contact with the housing 11 in the axial direction. The vane rotor 14 includes a cylindrical boss portion 14a and vanes 14b, 14c, and 14d.

  The boss portion 14 a is bolted coaxially with the cam shaft 2. As a result, the vane rotor 14 rotates in the clockwise direction of FIG. 2 in conjunction with the camshaft 2 and can rotate relative to the housing 11.

  Each of the vanes 14b to 14d protrudes radially outward from a portion that is substantially equidistant in the rotation direction in the boss portion 14a, and is accommodated in the corresponding accommodating chamber 50. The protruding side end surfaces of the vanes 14b to 14d are formed in an arcuate convex shape when viewed from the direction perpendicular to the plane of FIG. 2, and are in sliding contact with the inner peripheral wall surface of the cylindrical portion 12a.

  Each of the vanes 14b to 14d divides the corresponding accommodation chamber 50 into two in the rotation direction, thereby forming an advance angle chamber and a retard angle chamber between the housing 11 and the vane 14b to 14d. Specifically, an advance chamber 52 is formed between the shoe 12b and the vane 14b, an advance chamber 53 is formed between the shoe 12c and the vane 14c, and an advance chamber 54 is formed between the shoe 12d and the vane 14d. Further, a retard chamber 56 is formed between the shoe 12c and the vane 14b, a retard chamber 57 is formed between the shoe 12d and the vane 14c, and a retard chamber 58 is formed between the shoe 12b and the vane 14d.

  In the drive unit 10 configured as described above, the vane rotor 14 rotates relative to the housing 11 relative to the advance side by supplying hydraulic oil to the advance chambers 52 to 54 and discharging hydraulic oil from the retard chambers 56 to 58. Thus, the camshaft 2 is driven to the advance side with respect to the crankshaft. Therefore, in this case, the valve timing is advanced.

  On the other hand, the supply of hydraulic oil to the retard chambers 56 to 58 and the discharge of hydraulic fluid from the advance chambers 52 to 54 cause the vane rotor 14 to rotate relative to the housing 11 toward the retard side, thereby causing the camshaft 2 to move. Driven to the retard side with respect to the crankshaft. Therefore, in this case, the valve timing is retarded.

(Control part)
In the control unit 30 shown in FIGS. 1 and 2, the advance communication passages 72, 73, and 74 provided through the vane rotor 14 so as to open to the advance chambers 52, 53, and 54, respectively, Always communicate. The retard communication passages 76, 77, 78 provided through the vane rotor 14 so as to open to the retard chambers 56, 57, 58 are always in communication with the retard output passage 79.

  As shown in FIG. 1, the input passage 80 communicates with the discharge port of the pump 4 as a “fluid input source”, and the hydraulic oil pumped up from the oil pan 5 by the pump 4 is discharged. . Here, the pump 4 of this embodiment is a mechanical pump that is driven by a crankshaft. Therefore, during operation of the internal combustion engine, hydraulic oil is continuously input to the input passage 80. The drain passages 82 and 83 are provided so that the hydraulic oil can be returned to the oil pan 5.

  An input check valve 90 is provided in the input passage 80 connected to the spool valve 100 on the side opposite to the pump 4 so that the direction from the pump 4 toward the spool valve 100 is the valve opening direction and the reverse direction is the valve closing direction. It is arranged. As a result, the input check valve 90 is opened when the pump 4 side in the input passage 80 becomes higher in pressure than the spool valve 100 side (specifically, the input port 116 side described later), and the hydraulic oil to the valve 100 side is opened. Allow flow. On the other hand, the input check valve 90 is closed when the spool valve 100 side has a higher pressure than the pump 4 side in the input passage 80, and restricts the backflow of hydraulic oil from the valve 100 side.

  The spool valve 100 is an electromagnetic control valve that drives the spool in a reciprocating linear manner using the electromagnetic driving force generated by the solenoid 120. Here, the spool valve 100 communicates with the advance output port 112 communicating with the advance output passage 75, the retard output port 114 communicated with the retard output passage 79, and the input passage 80, and hydraulic oil is input from the pump 4. There are provided input ports 116 and drain ports 118 and 119 respectively communicating with the drain passages 82 and 83 for discharging hydraulic oil. The spool valve 100 switches the connection state of the input port 116 and the drain ports 118 and 119 with respect to the advance output port 112 and the retard output port 114 by spool movement in response to energization of the solenoid 120.

  The control circuit 180 is composed of, for example, a microcomputer and is electrically connected to the solenoid 120 of the spool valve 100. The control circuit 180 has a function of controlling the operation of the internal combustion engine together with a function of controlling energization to the solenoid 120.

  In the control unit 30 having such a configuration, the connection state of the ports 116, 118, and 119 with respect to the ports 112 and 114 is switched by controlling the energization of the solenoid 120 by the control circuit 180. As a result, when the input port 116 is connected to the advance angle output port 112, the input hydraulic oil from the pump 4 to the input passage 80 passes through the advance angle output passage 75 and the advance communication passages 72 to 74, and the advance chamber 52. To 54. At the same time, when the retard drain port 119 is connected to the retard output port 114, the hydraulic oil in the retard chambers 56 to 58 passes through the retard communication passages 76 to 78 and the retard output passage 79. It is discharged to 83 and returned from the passage 83 to the oil pan 5.

  On the other hand, when the input port 116 is connected to the retard output port 114, the input hydraulic oil from the pump 4 to the input passage 80 passes through the retard output passage 79 and the retard communication passages 76 to 78. To 58. At the same time, when the advance drain port 118 is connected to the advance output port 112, the hydraulic oil in the advance chambers 52 to 54 passes through the advance communication passages 72 to 74 and the advance output passage 75. It is discharged to 82 and returned from the passage 82 to the oil pan 5.

(Characteristic)
Hereinafter, features of the valve timing adjusting device 1 will be described in detail.

(Variable torque)
In the present embodiment, during operation of the internal combustion engine, fluctuating torque generated due to a spring reaction force or the like from the intake valve driven to open and close by the cam shaft 2 acts on the vane rotor 14 of the drive unit 10 through the cam shaft 2. Here, as shown in FIG. 3, the fluctuation torque is between a negative torque that urges the camshaft 2 toward the advance side with respect to the crankshaft and a positive torque that urges the camshaft 2 toward the retard side with respect to the crankshaft. In FIG. The fluctuating torque may be, for example, that the average torque becomes substantially zero when the peak torque T + of the positive torque becomes substantially equal to the peak torque T− of the negative torque, The average torque may be biased toward the positive torque side when the peak torque T + becomes larger than the peak torque T− of the negative torque.

(Passage formation structure)
In the following description, the vertical direction and horizontal direction of the valve timing adjusting device 1 on a horizontal plane are simply referred to as “vertical direction” and “horizontal direction”.

  As shown in FIGS. 1 and 4, the advance angle output passage 75 and the retard angle output passage 79 include a fixed joint 200 such as an engine head and a cam cover of the internal combustion engine, a bearing 201 that supports the cam shaft 2, and the cam shaft 2. Is provided. As shown in FIG. 4, the portion provided in the fixed joint 200 in the advance angle output passage 75 and the retard angle output passage 79 is a cylindrical hole-like accommodation hole penetrating the fixed joint 200 in the horizontal direction (left-right direction in the figure). 202 extends downward in the vertical direction.

  The input passage 80 passes through the fixed node 200 so that a part of the input passage 80 is located above the accommodation hole 202 in the vertical direction and the end opposite to the accommodation hole 202 can be input with hydraulic oil from the pump 4. Is provided.

  The advance drain passage 82 and the retard drain passage 83 extend from the accommodation hole 202 upward in the vertical direction, and the end of the opposite side of the accommodation hole 202 opens upward in the vertical direction. 200 is provided. As a result, the advance drain passage 82 and the retard drain passage 83 cause the hydraulic oil discharged from the advance drain port 118 and the retard drain port 119, respectively, to move upward and downward in the vertical direction of the fixed node 200 (illustrated). No) can return to the oil pan 5.

  In particular, the advance drain passage 82 of the present embodiment forms an advance fluid reservoir portion 82a for temporarily accumulating hydraulic oil discharged from the advance drain port 118 in the entire passage 82. Yes. As a result, the advance fluid reservoir 82a opens at the upper surface 204 of the fixed node 200 at the end opposite to the accommodation hole 202, and is open to the atmosphere through the opening. Here, when the camshaft 2 is driven to the advance side with respect to the crankshaft, the volume of the advance fluid reservoir 82a is caused by the action of a negative torque that biases the camshaft 2 to the advance side of the fluctuation torque. It is preferable to set it to be equal to or greater than the maximum value of the volume expansion amount of the advance chambers 52 to 54 for volume expansion.

  On the other hand, the retarded drain passage 83 of the present embodiment forms a retarded fluid reservoir 83a for temporarily accumulating hydraulic oil discharged from the retarded drain port 119 in the entire passage 83. Yes. As a result, the retarded fluid reservoir 83a opens to the upper surface 204 of the fixed node 200 at the end opposite to the accommodation hole 202, and is open to the atmosphere through the opening. Here, when the camshaft 2 is driven to the retard side with respect to the crankshaft, the volume of the retarded fluid reservoir 83a is caused by the action of a positive torque that biases the camshaft 2 to the retard side of the variable torque. It is preferably set to be equal to or greater than the maximum value of the volume expansion amount of the retardation chambers 56 to 58 whose volume is expanded.

  As described above, in the present embodiment, the fixed node 200, the bearing 201, and the cam shaft 2 jointly constitute a “passage forming body” that forms the passages 75, 79, 80, 82, and 83.

(Spool valve)
As shown in FIG. 4, the spool valve 100 of this embodiment includes a sleeve 110, a solenoid 120, a spool 130, a drive shaft 139, and a return spring 140.

  The sleeve 110 is formed in a cylindrical shape from metal. The sleeve 110 has an advance drain port 118, an advance output port 112, an input port 116, a retard output port 114, and a retard drain port 119 in the axial direction from the one end 110a side to the other end 110b side. In order. The sleeve 110 is housed and fixed coaxially in the housing hole 202 of the fixed node 200 with the solenoid 120 attached to the end 110 b on the side close to the retarded drain port 119.

  As a result, the advance drain port 118, the input port 116, and the retard drain port 119 each open toward the upper side in the vertical direction, and the advance fluid reservoir 82a of the advance drain passage 82 and the input passage 80 in the fixed node 200. The retarded angle fluid reservoir 83a of the retarded drain passage 83 communicates with the retarded angle fluid reservoir 83a. On the other hand, each of the advance angle output port 112 and the retard angle output port 114 opens downward in the vertical direction, and communicates with the advance angle output passage 75 and the retard angle output passage 79 in the fixed node 200.

  The spool 130 is formed in a skewer shape with metal and is accommodated coaxially in the sleeve 110. A drive shaft 139 that is electromagnetically driven by the solenoid 120 is coaxially connected to one end portion 130 a of the spool 130, so that the spool 130 can reciprocate in the axial direction together with the drive shaft 139. The spool 130 is provided with an advance support land 132, an advance switch land 134, a retard switch land 136, and a retard support land 138 in the reverse order in the axial direction from the one end portion 130a to the other end portion 130b. ing.

  The advance angle support land 132 is always slidably supported by the sleeve 110 on the end 110 a side of the advance angle drain port 118. The advance angle switching land 134 is slidably supported by the sleeve 110 on at least one of the advance angle drain port 118 side and the input port 116 side across the advance angle output port 112. Here, when the advance angle switching land 134 is supported only on the advance angle drain port 118 side of the advance angle output port 112 as shown in FIG. The connection is made through a gap between the land 134 and the retard switching land 136. Further, as shown in FIG. 5, when the advance angle switching land 134 is supported only on the input port 116 side of the advance angle output port 112, the advance drain port 118 is connected to the advance angle output port 112. 134 and the advance support land 132 are connected through a gap. Further, as shown in FIG. 6, when the advance angle switching land 134 is supported by both the advance drain port 118 side and the input port 116 side of the advance angle output port 112, the advance angle output port 112 is connected to another port. It will be blocked.

  As shown in FIG. 4, the retard support land 138 is always slidably supported by the sleeve 110 on the end 110 b side of the drain port 119. The retard switching land 136 is slidably supported by the sleeve 110 on at least one of the retard drain port 119 side and the input port 116 side across the retard output port 114. Here, as shown in FIG. 5, when the retard switching land 136 is supported only on the retard drain port 119 side of the retard output port 114, the input port 116 performs retard switching with respect to the retard output port 114. The connection is made through the gap between the land 136 and the advance angle switching land 134. As shown in FIG. 4, when the retard switching land 136 is supported only on the input port 116 side of the retard output port 114, the retard drain port 119 is connected to the retard output port 114. 136 and the retarded support land 138 are connected through a gap. Further, as shown in FIG. 6, when the retard switching land 136 is supported on both the retard drain port 119 side and the input port 116 side of the retard output port 114, the retard output port 114 is connected to another port. It will be blocked.

  The return spring 140 is made of a metal compression coil spring and is accommodated coaxially in the sleeve 110. The return spring 140 is interposed between the end 110 a of the sleeve 110 opposite to the solenoid 120 and the advance support land 132 of the spool 130. The return spring 140 generates a restoring force for urging the spool 130 toward the solenoid 120 in the axial direction by compression deformation. On the other hand, the solenoid 120 generates an electromagnetic driving force that urges the spool 130 toward the return spring 140 in the axial direction by energization. Therefore, in the spool valve 100, the spool 130 is driven in accordance with the balance between the restoring force generated by the return spring 140 and the electromagnetic driving force generated by the solenoid 120.

  In the present embodiment, the check valves 210 and 230 are incorporated in the connection passages 220 and 240 of the spool 130, respectively, as shown in FIGS.

  Specifically, as shown in FIG. 4, one end 221 of the advance connection passage 220 formed in the spool 130 has a plurality of outer peripheral surfaces of the spool 130 between the advance support lands 132 and the advance switching lands 134. It opens at a place. Further, the other end portion 222 of the advance angle connecting passage 220 opens at a plurality of locations on the outer peripheral surface of the spool 130 in the advance angle switching land 134. With the above configuration, the advance connection passage 220 always communicates with the advance drain port 118 through the gap between the lands 132 and 134, and always communicates with the advance output port 112 through the advance switching land 134. ing.

  The advance check valve 210 is disposed in the advance connection passage 220 such that the direction from the one end 221 to the other end 222 is the valve opening direction and the reverse direction is the valve closing direction. Here, the advance check valve 210 of this embodiment is formed by combining an advance valve seat 212, an advance valve member 214, and an advance elastic member 216.

  The advance valve seat 212 is formed by a conical surface that decreases in diameter toward the end 221 side of the inner peripheral wall surface of the advance connection passage 220. The advance valve member 214 made of metal has a ball shape and is disposed closer to the end 222 side than the advance valve seat 212 in the advance connection passage 220 and is separated from the advance valve seat 212 in the axial direction. It can be seated. The advance angle elastic member 216 is formed of a metal compression coil spring, and is interposed between the advance valve member 214 and the inner wall surface 224 of the passage 220 in the advance angle connection passage 220. Accordingly, the advance elastic member 216 generates a restoring force that urges the advance valve member 214 toward the advance valve seat 212 by compression deformation.

  In the advance check valve 210 having such a configuration, the end 222 side in communication with the advance output port 112 in the advance connection passage 220 has a lower pressure than the end 221 in communication with the advance drain port 118. As shown in FIG. 7, the advance valve member 214 moves to the end 222 side. As a result, the advance valve member 214 is opened away from the advance valve seat 212, so that the hydraulic oil flow from the end 221 side toward the end 222 side is allowed.

  On the other hand, in the advance check valve 210, the end 222 side in the advance connection passage 220 has a higher pressure than the end 221, so that the advance valve member 214 is moved to the end 221 as shown in FIG. Moving. As a result, the advance valve member 214 sits on the advance valve seat 212 and closes, so that the hydraulic oil flow from the end 222 side toward the end 221 side is restricted.

  As shown in FIG. 4, one end portion 241 of the retard connection passage 240 formed in the spool 130 opens at a plurality of locations on the outer peripheral surface of the spool 130 between the retard switching land 136 and the retard support land 138. is doing. Further, the other end portion 242 of the retard connection passage 240 opens at a plurality of locations on the outer peripheral surface of the spool 130 in the retard switching land 136. With the above configuration, the retard connection passage 240 always communicates with the retard drain port 119 through the gap between the lands 136 and 138, and communicates with the retard output port 114 at all times through the retard switching land 136. ing.

  The retard check valve 230 is disposed in the retard connection passage 240 such that the direction from the one end 241 to the other end 242 is the valve opening direction and the opposite direction is the valve closing direction. Here, the retard check valve 230 of the present embodiment has a configuration according to the advance check valve 210, that is, a configuration in which the retard valve seat 232, the retard valve member 234, and the retard elastic member 236 are combined. ing.

  However, in the retard check valve 230, the retard valve seat 232 is formed by a conical surface whose diameter decreases toward the end 241 side in the inner peripheral wall surface of the retard connection passage 240. The retard valve member 234 is disposed in the retard connection passage 240 closer to the end 222 than the retard valve seat 232, and can be separated from the retard valve seat 232 in the axial direction. The retard elastic member 236 is made of a metal compression coil spring, and is interposed between the retard valve member 234 and the inner wall surface 244 of the passage 240 in the retard connection passage 240. As a result, the retarded angle elastic member 236 generates a restoring force that urges the retarded valve member 234 toward the retarded valve seat 232 by compression deformation.

  In the retard check valve 230 configured as described above, the retard output port 114 and the end 242 connected to the retard output port 114 have a lower pressure than the retard drain port 119 and the end 241 connected to the retard connecting passage 240. As shown in FIG. 8, the retard valve member 234 moves to the end 242 side. As a result, the retard valve member 234 opens from the retard valve seat 232 so that the hydraulic oil flow from the end 241 side toward the end 242 side is allowed.

  On the other hand, in the retard check valve 230, the end 242 side in the retard connection passage 240 has a higher pressure than the end 241, so that the retard valve member 234 moves toward the end 241 as shown in FIG. 5. Moving. As a result, the retard valve member 234 sits on the retard valve seat 232 and closes, so that the hydraulic fluid flow from the end 242 side toward the end 241 side is restricted.

(Valve timing adjustment operation)
During operation of the internal combustion engine in which the pump 4 is driven in the present embodiment, the control circuit 180 calculates the actual phase and the target phase for the phase of the camshaft 2 with respect to the crankshaft (hereinafter referred to as “engine phase”), and the calculation thereof. The energization current to the solenoid 120 of the spool valve 100 is controlled according to the result. As a result, the spool 130 of the spool valve 100 moves, and the supply or discharge of the hydraulic oil corresponding to the moving position is realized with respect to the advance chambers 52 to 54 and the retard chambers 56 to 58. Adjusted. Hereinafter, the valve timing adjustment operation by the valve timing adjustment device 1 of the present embodiment will be described in detail.

(1) Advance Advancing Operation Hereinafter, an operation when the valve timing is advanced by changing the engine phase to the advance side of the camshaft 2 with respect to the crankshaft will be described.

When operating conditions are established which represents the accelerator-off state or a low and middle speed high-load operation state or the like in the internal combustion engine, the control circuit 180 controls the value larger than the predetermined reference value I _b the current supplied to the solenoid 120 . As a result, the spool 130 connects the input passage 80 connected to the input port 116 to the advance output passage 75 connected to the advance output port 112 and the retard output passage 79 connected to the retard output port 114. On the other hand, it moves to the advance position of FIGS. 4 and 7 so that the retard drain passage 83 connected to the retard drain port 119 is connected. Here, in the advance position, the advance connection passage 220 of the spool 130 passes through the end portions 222 and 221 through the advance output port 112 and the advance drain port 118, respectively, and the advance output passage 75 and the advance drain passage 82. The advance fluid reservoir 82a communicates with each other to connect the elements 75 and 82a.

  Therefore, when a negative torque of the varying torque acts on the vane rotor 14 from the camshaft 2, the input hydraulic oil from the pump 4 to the input passage 80 flows from the advance output passage 75 to the advance communication passages 72 to 74 shown in FIG. To the advance chambers 52 to 54 through the passages 72 to 74. When negative torque is applied, the hydraulic oil in the retard chambers 56-58 is discharged from the retard communication passages 76-78 to the retard drain passage 83 through the retard output passage 79 as shown in FIG. The retarded angle fluid reservoir 83a of the passage 83 is accumulated until it is filled.

  Further, when the internal pressure of the advance chambers 52 to 54 whose volume has been expanded due to the negative torque acts as a negative pressure, in the advance connection passage 220, from the advance fluid reservoir 82a side held at atmospheric pressure by opening to the atmosphere. Also, the negative pressure advance output passage 75 side becomes a low pressure. That is, since the end 222 side has a lower pressure than the end 221 side, the advance check valve 210 opens as shown in FIG. Therefore, as will be described later, the hydraulic oil stored in the advanced fluid reservoir 82a in the filled state at the retarded position of the spool 130 moves toward the advanced chambers 52 to 54 in the negative pressure state, as shown in FIG. It will be sucked through the passages 220, 75, 72-74. According to this, it is sucked into the advance chambers 52 to 54 through the device clearances on the passages 220, 75, 72 to 74 (for example, the device clearance at the interface between the bearing 201 and the cam shaft 2 forming the advance output passage 75). The amount of air to be reduced is reduced. In particular, in the case of the advance fluid reservoir 82a whose volume is set to be equal to or larger than the maximum volume expansion amount of the advance chambers 52 to 54 due to negative torque, the filled hydraulic fluid is sucked into the advance chambers 52 to 54. Even if it does not become empty easily, the reduction effect of the air suction amount to the advance chambers 52 to 54 is improved. For this reason, the amount of hydraulic oil supplied to the advance chambers 52 to 54 whose volume has been increased can be ensured, so even if the variable torque is reversed from negative torque to positive torque, the cam is shifted to the retard side with respect to the crankshaft. The relative rotation of the vane rotor 14 that drives the shaft 2 can be suppressed.

  On the other hand, when the advance chambers 52 to 54 are compressed by the action of the positive torque of the variable torque, the hydraulic oil whose pressure has increased to the positive pressure side is advanced from the advance chambers 52 to 54 as shown in FIG. It flows into the output passage 75. As a result, in the advance angle connection passage 220 that connects the advance angle output passage 75 and the advance angle fluid reservoir 82a, the advance angle output passage 75 side that is a positive pressure is higher in pressure than the advance angle fluid reservoir portion 82a side of atmospheric pressure. It becomes. That is, since the end 222 side is at a higher pressure than the end 221, the advance check valve 210 is closed as shown in FIG. 4, and the oil flowing into the advance output passage 75 flows from the advance connection passage 220. It is not discharged to the advance fluid reservoir 82a. Further, in the input passage 80 connected to the advance angle output passage 75, the spool valve 100 side becomes higher in pressure than the pump 4 side, and the input check valve 90 in FIG. The oil flowing into the passage 75 is restricted from flowing back into the input passage 80. According to the above, it is possible to prevent the hydraulic oil in the advance chambers 52 to 54 from flowing out to the advance fluid reservoir 82a through the passages 72 to 75, 220.

  According to the above, the function of the advance check valve 210 is properly demonstrated in a timely manner, and a sufficient amount of hydraulic oil is supplied to the advance chambers 52 to 54, while the hydraulic oil is supplied from the retard chambers 56 to 58. Therefore, it is possible to achieve a high advance angle response.

(2) Delay Angle Operation Hereinafter, an operation when the engine phase is changed to the retard side of the camshaft 2 with respect to the crankshaft to retard the valve timing will be described.

When operating conditions are established which represents the normal operation state of the light load in the internal combustion engine, the control circuit 180 controls the value smaller than the reference value I _b the current supplied to the solenoid 120. As a result, the spool 130 connects the input passage 80 communicated with the input port 116 to the retard output passage 79 communicated with the retard output port 114 and the advance output passage 75 communicated with the advance output port 112. On the other hand, it moves to the retard position in FIGS. 5 and 8 so that the advance drain passage 82 connected to the advance drain port 118 is connected. Here, in the retard position, the retard connection passage 240 of the spool 130 passes through the end portions 242, 241 through the retard output port 114 and the retard drain port 119, respectively, and the retard output passage 79 and the retard drain passage 83. The retarding fluid reservoir 83a is connected to connect the elements 79 and 83a.

  Therefore, when a positive torque of the variable torque acts on the vane rotor 14 from the camshaft 2, the input hydraulic oil from the pump 4 to the input passage 80 flows from the retard output passage 79 to the retard communication passages 76 to 78 shown in FIG. Are supplied to the retarding chambers 56 to 58 from the passages 76 to 78. When positive torque is applied, the hydraulic oil in the advance chambers 52 to 54 is discharged from the advance communication passages 72 to 74 to the advance drain passage 82 through the advance output passage 75 as shown in FIG. The advance fluid reservoir 82a of the passage 82 is stored until it is filled.

  Further, when the internal pressure of the retarded angle chambers 56 to 58 whose volume has been expanded due to the action of the positive torque becomes negative, the retarded angle connecting passage 240 receives from the retarded angle fluid reservoir 83a side that is held at atmospheric pressure by opening to the atmosphere. Also, the negative pressure retarded output passage 79 side becomes a low pressure. That is, since the end 242 side is at a lower pressure than the end 241 side, the retarded check valve 230 is opened as shown in FIG. Therefore, as described above, the hydraulic oil stored in the retarded fluid reservoir 83a at the advanced position of the spool 130 in the filled state moves toward the retarded chambers 56 to 58 in the negative pressure state, as shown in FIG. It will be sucked through the passages 240, 79, 76-78. According to this, the device is sucked into the retard chambers 56 to 58 through the device clearances on the passages 240, 79, 76 to 78 (for example, the device clearance at the interface between the bearing 201 and the cam shaft 2 forming the retard output passage 79). The amount of air to be reduced is reduced. Here, in particular, in the case of the retarded fluid reservoir 83a whose volume is set to be equal to or greater than the maximum volume expansion amount of the retard chambers 56 to 58 due to the positive torque, the filled hydraulic fluid is sucked into the retard chambers 56 to 58. Even if it does not become empty easily, the reduction effect of the air suction amount to the retardation chambers 56 to 58 is improved. For this reason, the amount of hydraulic oil supplied to the retarded chambers 56 to 58 whose volume has been increased can be ensured, so even if the variable torque is reversed from positive torque to negative torque, the cam is advanced toward the advance side with respect to the crankshaft. The relative rotation of the vane rotor 14 that drives the shaft 2 can be suppressed.

  On the other hand, when the retard chambers 56 to 58 are compressed by the action of the negative torque of the variable torque, the hydraulic oil whose pressure has increased to the positive pressure side is retarded from the retard chambers 56 to 58 as shown in FIG. It flows into the output passage 79. As a result, in the retarded angle connecting passage 240 that connects between the retarded angle output passage 79 and the retarded fluid reservoir 83a, the retarded output passage 79 side that is positive pressure is higher in pressure than the retarded fluid reservoir 83a side of atmospheric pressure. It becomes. That is, since the end portion 242 side is at a higher pressure than the end portion 241 side, the retard check valve 230 is closed as shown in FIG. 5, and the oil flowing into the retard output passage 79 flows from the retard connection passage 240. It is not discharged to the retarded fluid reservoir 83a. Further, in the input passage 80 connected to the retard output passage 79, the spool valve 100 side becomes higher than the pump 4 side, and the input check valve 90 in FIG. The oil flowing into the passage 79 is restricted from flowing back into the input passage 80. According to the above, it is possible to prevent the hydraulic oil in the retard chambers 56 to 58 from flowing out to the retard fluid reservoir 83a through the passages 76 to 79, 240.

  According to the above, the function of the retard check valve 230 is properly performed in a timely manner, and a sufficient amount of hydraulic fluid is supplied to the retard chambers 56 to 58, while the hydraulic fluid is supplied from the advance chambers 52 to 54. As a result, it is possible to achieve high retardation response.

(3) Holding Operation Hereinafter, an operation in the case where the engine phase is held in a predetermined target phase region and the valve timing is substantially held will be described.

When operating conditions representative of the stable operating condition and the like, such as an accelerator of the holding state is established in the internal combustion engine, the control circuit 180 controls the current supplied to the solenoid 120 to the reference value I _b. As a result, the spool 130 moves to the holding position in FIG. 6 so as to block both the input port 116 and the drain ports 118 and 119 with respect to the advance output port 112 and the retard output port 114. Here, in the holding position, the connection passages 220 and 240 of the spool 130 communicate the respective end portions 222 and 242 with the corresponding output passages 75 and 79, and the respective end portions 221 and 241 correspond to the corresponding fluid reservoirs 82a. , 83a. That is, the output passages 75 and 79 and the fluid reservoirs 82a and 83a are connected by the connection passages 220 and 240.

  Therefore, the input hydraulic fluid from the pump 4 to the input passage 80 is passed to any of the advance chambers 52 to 54 and the retard chambers 56 to 58 by blocking the input port 116 with respect to the advance and retard output ports 112 and 114. It will not be supplied. As a result, the hydraulic oil is confined in the chambers 52 to 54 and 56 to 58, so that the relative rotation of the vane rotor 14 with respect to the housing 11 due to the action of the variable torque is suppressed. As a result, the negative pressure generated in each of the chambers 52 to 54 and 56 to 58 is reduced. Here, in the prior art, the compressive air is sucked from the device clearance (for example, the device clearance at the interface between the camshaft 2 and the bearing 201) by the generated negative pressure, so that the phase variation during holding increases with time. . On the other hand, according to the present embodiment, incompressible oil is sucked from the fluid reservoirs 82a and 83a by the generated negative pressure, so that phase fluctuation during holding is suppressed.

  According to the above, it is possible to realize substantial retention of the valve timing by suppressing the change of the engine phase.

  According to the embodiments described so far, the valve timing adjustment suitable for the internal combustion engine can be performed quickly and accurately.

(Other embodiments)
Although one embodiment of the present invention has been described above, the present invention is not construed as being limited to the embodiment described, and can be applied to various embodiments without departing from the scope of the invention. .

  Specifically, in the drive unit 10, for example, an elastic member such as an assist spring that biases the cam shaft 2 may be provided on the side opposite to the bias side of the average torque of the variable torque. As for the drive unit 10, the housing 11 may be rotated in conjunction with the camshaft 2 and the vane rotor 14 may be rotated in conjunction with the crankshaft.

  Further, with respect to the fixed node 200 as the “passage forming body”, the fluid reservoirs 82a and 83a of the drain passages 82 and 83 are accommodated as shown in the modified example of FIG. 9 (the figure is an example of the fluid reservoir 82a). It may be formed in a shape that extends in the horizontal direction from 202 and bends upward in the vertical direction. In this case, for example, as shown in FIG. 9, the fluid reservoirs 82 a and 83 a may be opened on the upper surface 204 at a position lower than the uppermost end in the vertical direction of the accommodation hole 202 in the fixed node 200. In these fluid reservoirs 82a and 83a, the hydraulic oil can be accumulated at atmospheric pressure.

  Furthermore, as for the spool valve 100, in addition to a configuration in which the spool 130 is driven by the solenoid 120, for example, a valve that drives the spool 130 by a piezo actuator or a hydraulic actuator may be adopted. Furthermore, regarding the spool valve 100, the output port 114 is connected to the advance chambers 52 to 54 via the output passage 75 and the communication passages 72 to 74, and the output port 112 is connected to the output passage 79 and the communication passages 76 to 78. The retard chambers 56 to 58 may communicate with each other. In this case, the positions in FIGS. 4 and 7 are retard positions for the retard operation, and the positions in FIGS. 5 and 8 are advance positions for the advance operation.

  In addition to the device that adjusts the valve timing of the intake valve, the present invention provides a device that adjusts the valve timing of the exhaust valve as a “valve”, and a device that adjusts the valve timing of both the intake valve and the exhaust valve. It can also be applied.

It is a block diagram which shows the valve timing adjustment apparatus by one Embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is a schematic diagram for demonstrating the fluctuation | variation torque which acts on the drive part of FIG. It is sectional drawing which shows typically the detailed structure and the operating state of the spool valve of FIG. It is sectional drawing which shows the operating state of the spool valve of FIG. 1 typically. It is sectional drawing which shows the operating state of the spool valve of FIG. 1 typically. It is sectional drawing which shows the operating state of the spool valve of FIG. 1 typically. It is sectional drawing which shows the operating state of the spool valve of FIG. 1 typically. It is sectional drawing for demonstrating the modification of one Embodiment of this invention. It is a characteristic view for demonstrating the problem of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve timing adjustment apparatus, 2 Cam shaft (passage formation body), 4 Pump (fluid input source), 5 Oil pan, 10 Drive part, 11 Housing (drive rotary body), 12 Shoe housing, 12a Tube part, 12b, 12c , 12d shoe, 13 sprocket, 14 vane rotor (driven rotor), 14a boss part, 14b, 14c, 14d vane, 30 control part, 50 accommodating chamber, 52, 53, 54 advance angle chamber, 56, 57, 58 retard angle Chamber, 72, 73, 74 advance communication passage, 76, 77, 78 retard communication passage, 79 retard output passage, 80 input passage, 82 advance drain passage, 82a advance fluid reservoir, 83 retard drain passage 83a retarding fluid reservoir, 90 input check valve, 100 spool valve, 110 sleeve, 112 advance output port, 114 retard output port 116, input port, 118 advance drain port, 119 retard angle drain port, 120 solenoid, 130 spool, 132 advance support land, 134 advance switch land, 136 retard switch land, 138 retard support land, 140 return Spring, 180 control circuit, 200 fixed node (passage forming body), 201 bearing (passage forming body), 202 receiving hole, 204 upper surface, 210 advance check valve, 212 advance valve seat, 214 advance valve member, 216 Advance angle elastic member, 220 Advance angle connection passage, 221, 222, 241, 242 End, 230 Delay angle check valve, 232 Delay angle valve seat, 234 Delay angle valve member, 236 Delay angle elastic member, 240 Delay angle connection aisle

Claims (4)

A valve timing adjusting device for adjusting a valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine,
A drive rotor that rotates in conjunction with the crankshaft;
By rotating in conjunction with the camshaft, forming an advance chamber and a retard chamber in the rotational direction with the drive rotor, and working fluid is supplied to the advance chamber or the retard chamber A driven rotator for driving the camshaft forward or retarded with respect to the crankshaft;
An input passage through which a working fluid is input from a fluid input source, an advance output passage and a retard output passage for outputting the working fluid to the advance chamber and the retard chamber, and an advance drain passage from which the working fluid is discharged And a passage forming body that forms a retarded drain passage,
When the camshaft is driven to the advance side relative to the crankshaft, the input passage is connected to the advance output passage by moving the spool to an advance position when the camshaft is driven to the advance side with respect to the crankshaft. In addition, when the retard drain passage is connected to the retard output passage and the camshaft is driven to the retard side with respect to the crankshaft, the spool is moved to the retard position, thereby the retard output A spool valve that connects the input passage to the passage and connects the advance drain passage to the advance output passage, and a valve timing adjusting device comprising:
The advance drain passage and the retard drain passage that are opened to the atmosphere have an advance fluid reservoir portion and a retard fluid reservoir portion that store the working fluid discharged to each,
The spool is
An advance connection passage that connects between the advance output passage and the advance fluid reservoir, under the state of movement of the spool to the advance position;
A retard connection passage that connects between the retard output passage and the retard fluid reservoir under the state of movement of the spool to the retard position;
And forming
Under the state of movement of the spool to the advance angle position, the advance angle output passage side in the advance angle connection passage becomes lower in pressure than the advance fluid reservoir side, and the valve is opened and the advance angle is increased in the advance connection passage. An advance check valve that closes when the angle output passage side becomes higher in pressure than the advance fluid reservoir side;
When the spool is moved to the retarded position, the retarded output passage side in the retarded connection passage is lower in pressure than the retarded fluid reservoir side, and the valve is opened and the retarded connection passage is in the retarded connection passage. A retarded check valve that closes when the angular output passage side becomes higher in pressure than the retarded fluid reservoir side;
A valve timing adjusting device characterized by incorporating a valve.   The advance fluid reservoir and the retard fluid reservoir are opened upward in the passage forming body, and the advance drain passage and the retard drain passage are opened to the atmosphere in the opening. The valve timing adjusting device according to claim 1. The volume of the advance fluid reservoir is such that when the cam shaft is driven to the advance side with respect to the crank shaft, the volume of the advance chamber is increased by a variable torque that urges the cam shaft to the advance side. Set to more than the volume expansion amount,
When the camshaft is driven to the retard side with respect to the crankshaft, the retarding fluid reservoir has a volume that is increased by a variable torque that biases the camshaft toward the retard side. The valve timing adjusting device according to claim 1, wherein the valve timing adjusting device is set to a volume expansion amount or more.   An input check valve that opens when the fluid input source side becomes higher than the spool valve side in the input passage and closes when the spool valve side becomes higher than the fluid input source side in the input passage. The valve timing adjusting device according to any one of claims 1 to 3, further comprising:

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