JP5842531B2 - Hydraulic control device - Google Patents

Description

  The present invention relates to a hydraulic control apparatus that controls the hydraulic pressure of oil boosted by a pump.

  Conventionally, devices driven by hydraulic pressure have been widely used. In such a device, a hydraulic control device that controls a hydraulic pressure for performing drive control is used. As such a hydraulic control device, there is one described in Patent Document 1 which is cited below.

  The vehicle oil supply device described in Patent Document 1 includes a pump that is driven by the rotation of an engine to discharge oil, a hydraulic actuator that is operated by the hydraulic pressure of oil discharged from the pump, and oil discharged from the pump. And an engine lubrication device that lubricates each member of the engine using the hydraulic pressure of the engine. This vehicle oil supply device restricts the oil flow rate from the pump to the engine lubrication device when the oil pressure is low, and gives priority to oil supply from the pump to the hydraulic actuator.

JP 2009-299573 A

  Here, considering the efficiency of the pump, it is desirable to satisfy the required hydraulic pressure from the hydraulic actuator with a low capacity pump. In such a case, it is possible to reduce the load on the pump by increasing the oil pressure discharged from the pump and then adjusting the oil pressure to the required oil pressure. However, in the technique described in Patent Document 1, although the pressure increase and pressure adjustment hydraulic pressure can be continuously changed, the flow area is changed only in one stage. If it is satisfied, the required oil pressure in the middle rotation range cannot be satisfied. For this reason, when there are multiple required hydraulic pressures of the hydraulic actuator in the low to middle and high engine speed ranges, the required hydraulic pressure of the hydraulic actuator is satisfied while sufficiently reducing the work of the pump. I can't let you.

  In view of the above problems, an object of the present invention is to provide a hydraulic control device capable of adjusting the hydraulic pressure as the engine speed changes.

The characteristic configuration of the hydraulic control device according to the present invention for achieving the above object is as follows:
A pump that is driven by the rotation of the engine to discharge oil;
A first predetermined portion to which oil discharged from the pump is supplied;
A first oil passage communicating the pump and the first predetermined portion;
A second oil passage provided in communication with the first oil passage and supplying oil to a second predetermined portion different from the first predetermined portion;
A flow that is provided in the second oil passage and increases the flow passage area of the second oil passage by increasing the oil pressure of the second oil passage, and decreases the flow passage area by reducing the oil pressure of the second oil passage. A road area adjustment unit,
The flow path area adjusting unit is
A supply unit to which the oil in the second oil passage is supplied;
A spool having a pressure receiving surface for receiving the oil pressure of the supply unit and a back surface on the back side of the pressure receiving surface , and reciprocating in a direction intersecting the second oil passage to adjust a flow area of the second oil passage; ,
Biasing means for biasing the spool from the back surface toward the pressure receiving surface;
The hydraulic pressure of the second oil passage is communicated with the supply section in an initial communication state until the hydraulic pressure of the second oil passage reaches a predetermined pressure, and the adjusted hydraulic pressure in which the hydraulic pressure of the oil discharged from the pump is adjusted is discharged from the flow path area adjusting section. A discharge section;
The spool is formed in the spool, which increases the flow passage area of the second oil passage in a stepwise manner from the initial communication state while the spool moves to one side in the reciprocating movement direction due to an increase in the oil pressure of the second oil passage. A plurality of communication passages,
It is in the point comprised with.

  Thus, by providing a plurality of communication passages in the spool, when the engine speed changes, the hydraulic pressure can be adjusted in a plurality of stages regardless of the engine speed. In the case of this configuration, when the spool moves and the flow passage area of the second oil passage increases as the engine speed increases, the degree of increase in the flow passage area is changed stepwise. Can do. For example, when the spool moves with respect to the second oil passage, the communication passage provided in the spool is gradually exposed to the second oil passage, and the flow passage area of the second oil passage gradually increases. In addition, within a predetermined time after the specific communication path of the spool is exposed to the second oil path, the exposed area of the communication path with respect to the second oil path does not change even though the spool moves, and as a result, the second oil path A state occurs in which the flow path area does not change. Thus, in the case of the apparatus of this configuration, the flow passage area of the second oil passage changes stepwise in the process of increasing the engine speed and increasing the pressure of the second oil passage. As a result, the pressure of oil supplied to each part of the engine can be changed stepwise. Therefore, since the necessary hydraulic pressure can be set as appropriate for the increase in the engine speed, the pump is not forced to perform unnecessary work, which can contribute to an improvement in fuel consumption.

  Further, it is preferable that the plurality of communication paths are a plurality of grooves formed on the outer peripheral surface of the spool.

  With such a configuration, the plurality of communication paths can be easily processed by cutting the outer periphery of the spool. Further, since the height and depth of the groove can be arbitrarily set, a spool having an intended flow path area can be easily obtained.

  Further, after the spool is maintained in a state in which the flow passage area of the second oil passage is constant during the movement of the spool, a new flow passage is formed through the plurality of communication passages or the top of the spool. It is preferred that it is configured to be formed.

  With such a configuration, for example, when both the first communication path and the second communication path are in the communication state from the initial communication state, the second communication with respect to the flow area of the first communication path in the initial communication state. Since the passage area of the passage is added, the passage area of the second oil passage is increased. For this reason, the hydraulic pressure gradient when both the first communication path and the second communication path are in the communication state can be remarkably gentle with respect to the hydraulic pressure gradient in the initial communication state. Further, for example, when only the second communication path communicates with the second communication path and the top of the spool, the top of the spool with respect to the flow area of the second communication path. Since the flow passage area of the flow passage through the second is added, the flow passage area of the second oil passage increases. For this reason, the hydraulic pressure gradient when both the first communication path and the second communication path are in a communication state is remarkably gentle with respect to the hydraulic pressure gradient in a state where the first communication path and the second communication path are circulated only through the second communication path. Can do. Therefore, since the hydraulic gradient can be changed in each state, the loss can be greatly reduced as compared with a conventional hydraulic control device that does not change the hydraulic gradient as appropriate.

It is a figure which shows typically the whole structure of a hydraulic control apparatus. It is a figure which shows typically operation | movement of a hydraulic pressure adjustment part. It is a figure which shows the communicating path which concerns on other embodiment. It is a figure which shows the spool which concerns on other embodiment. It is a figure which shows the communicating path which concerns on other embodiment.

  Hereinafter, embodiments of the present invention will be described in detail. The hydraulic control apparatus 100 according to the present invention has a function of generating a hydraulic pressure corresponding to the required hydraulic pressure from various apparatuses even when the rotational speed of a pump driven by a vehicle engine is changed. Hereinafter, it demonstrates using drawing.

1. Configuration of Hydraulic Control Device FIG. 1 is a block diagram schematically showing the configuration of the hydraulic control device 100. As shown in FIG. 1, the hydraulic control device 100 includes a pump 10, a first predetermined portion 11, a second predetermined portion 12, an oil control valve 15, a first oil passage 17, a second oil passage 18, and a flow passage area adjustment. Each functional unit of the unit 20 is configured.

  The pump 10 is driven by the rotation of an engine (not shown) to discharge oil. The rotation shaft of the pump 10 is connected and fixed to a crankshaft of an engine (not shown). Thereby, the pump 10 is mechanically driven by the rotational driving force of the crankshaft. The pump 10 sucks oil stored in the oil pan 1 and discharges the oil to the discharge oil passage 2. An oil filter 3 is disposed in the discharge oil passage 2 to filter small dust and sludge that has not been filtered by the oil strainer 4. The oil after filtering by the oil filter 3 is supplied to a first oil passage 17 to be described later.

  The first oil passage 17 communicates the pump 10 and the first predetermined portion 11. The first predetermined portion 11 is a portion to which oil discharged from the pump 10 is supplied. In the present embodiment, the first predetermined portion 11 corresponds to a valve opening / closing timing control device (VVT) 11A, a turbocharger 11B, and a piston jet 11C. Of course, some vehicles may not have the above three. Therefore, the first predetermined portion 11 may be at least one of a valve opening / closing timing control device (VVT) 11A, a turbocharger 11B, and a piston jet 11C.

  The oil control valve 15 is of an electromagnetic control type, and can control the supply, discharge, and supply / discharge shut-off of oil to the advance chamber communication passage and the retard chamber communication passage of the valve opening / closing timing control device 11A. The oil control valve 15 is configured as a spool type, and operates based on control of a power supply amount by an ECU (engine control unit) (not shown). That is, the oil control valve 15 supplies the oil to the advance oil passage 5A, discharges the oil from the retard oil passage 5B, discharges the oil from the advance oil passage 5A, supplies the oil to the retard oil passage 5B, and advances the angle. Control such as oil supply / discharge interruption to the oil passage 5A and the retarded oil passage 5B is possible. The control of the valve opening / closing timing control device 11A is well known and will not be described.

  The oil control valve 15 is set to be in a state where oil can be supplied to the advance oil passage 5A when power is supplied, and in a state where oil can be supplied to the retard oil passage 5B when power supply is stopped. The oil control valve 15 is for setting the opening degree by adjusting the duty ratio of the electric power supplied to the electromagnetic solenoid. Thereby, fine adjustment of the supply and discharge amount of oil is possible. In this way, by controlling the oil control valve 15, oil is supplied to, discharged from, or held in the advance and retard chambers of the valve opening / closing timing control device 11 </ b> A, and the oil of the oil is supplied to the vane. Pressure can be applied. This makes it possible to adjust the opening / closing timing of the engine valve.

  The first oil passage 17 branches to supply oil to the first predetermined portion other than the valve opening / closing timing control device 11A, that is, the turbocharger 11B and the piston jet 11C. The oil pressure discharged from the pump 10 is transmitted as it is to the turbocharger 11B and the piston jet 11C. In addition, it is also possible to provide things other than the valve opening / closing timing control device 11A, the turbocharger 11B, and the piston jet 11C as the first predetermined portion 11.

  The second oil passage 18 is provided in communication with the first oil passage 17 and supplies oil to the second predetermined portion 12 different from the first predetermined portion 11. In the present embodiment, the first predetermined portion 11 is the above-described valve opening / closing timing control device 11A, turbocharger 11B, and piston jet 11C. In the present embodiment, the second predetermined portion 12 corresponds to the main gallery 12. The second oil passage 18 is branched from the first oil passage 17.

  The second oil passage 18 is provided with a flow passage area adjusting unit 20. As will be described in detail later, the flow passage area adjusting unit 20 increases the flow passage area of the second oil passage 18 by increasing the hydraulic pressure of the second oil passage 18 and increases the flow passage area by reducing the hydraulic pressure of the second oil passage 18. Decrease. The flow passage area adjusting unit 20 is provided with the second oil passage 18 communicating therewith. The second oil passage 18 is also provided with a main gallery 12 that is driven by receiving the adjustment hydraulic pressure generated by the flow passage area adjustment unit 20. Therefore, the second oil passage 18 communicates the flow passage area adjusting unit 20 and the main gallery 12.

  The main gallery 12 indicates an entire sliding member such as a piston, a cylinder, a crankshaft bearing or the like (not shown). In addition, a device that is provided in a vehicle and driven by hydraulic pressure is also equivalent. The second oil passage 18 is provided with a hydraulic pressure sensor 13 that detects the hydraulic pressure. Based on the detection result of the hydraulic sensor 13, it is possible to clearly indicate to the vehicle occupant that the hydraulic pressure is low.

2. Next, the flow path area adjusting unit 20 will be described. The flow path area adjustment unit 20 includes a supply unit 21, a spool 22, an urging unit 23, a discharge unit 24, and a communication path 25. The supply unit 21 corresponds to a supply port to which oil in the second oil passage 18 is supplied. The oil in the second oil passage 18 is oil discharged from the pump 10 as described above. Accordingly, the supply unit 21 is provided in communication with the first oil passage 17 via the second oil passage 18.

The spool 22 is configured to include a pressure receiving surface 31 and a back surface 32. Here, the spool 22 according to the present embodiment is formed in a cylindrical shape, and only one end of the cylindrical axial direction is closed. The axially outer surface thus closed corresponds to the pressure receiving surface 31. A protruding portion 51 that protrudes outward in the axial direction is formed on the outer surface in the axial direction. As a result, the pressure receiving surface 31 is configured to have the top 41 of the housing 40 that houses the spool 22 and the predetermined gap 49.

  Here, although the details will be described later, the spool 22 is configured to be movable in the housing 40. Between the side portion 42 of the housing 40 and the case member 60 that accommodates the housing 40, a side flow passage 61 through which oil from the supply portion 21 flows to the gap 49 is provided. As a result, the pressure receiving surface 31 receives the hydraulic pressure from the supply unit 21, and the spool 22 reciprocates in the direction intersecting the second oil path 18 according to the hydraulic pressure to adjust the flow area of the second oil path 18. It becomes possible to do.

On the other hand, the back surface 32 is disposed on the back side of the pressure receiving surface 31. In other words, the axially inner surface of the opened portion corresponds to the back surface 32. Here, the urging means 23 is inserted and disposed at the other axial end of the cylindrical spool 22. As a result, the spool 22 is biased from the back surface 32 toward the pressure receiving surface 31. Therefore, when the hydraulic pressure is not supplied to the pressure receiving surface 31, the spool 22 moves to a position where the protruding portion 51 contacts the top portion 41. On the other hand, when the oil pressure is applied to the pressure receiving surface 31, the spool 22 moves against the urging force of the urging means 23. An air hole 45 is formed in the bottom portion 43 of the housing 40 so that the spool 22 can easily move along the side portion 44 of the housing 40.

  The discharge unit 24 discharges the adjusted hydraulic pressure in which the hydraulic pressure of the oil discharged from the pump 10 is adjusted from the flow path area adjusting unit 20. Although details will be described later, the flow path area adjusting unit 20 is configured to be switchable in a plurality of stages so that the oil pressure of the oil from the pump 10 can be adjusted. Here, as described above, when the hydraulic pressure is not supplied to the pressure receiving surface 31, the spool 22 is in a position where the protruding portion 51 contacts the top portion 41. Even in such a case, the flow channel area adjusting unit 20 according to the present embodiment is configured such that the supply unit 21 and the discharge unit 24 are in communication with each other. This state is referred to as an “initial communication state”. This initial communication state is maintained until the hydraulic pressure in the second oil passage 18 reaches a predetermined pressure.

  The communication path 25 is formed in the spool 22 and communicates the supply unit 21 and the discharge unit 24. A plurality of communication passages 25 are provided. In the present embodiment, the communication path 25 will be described as being the first communication path 25A and the second communication path 25B. The plurality of communication paths 25 correspond to a plurality of grooves formed on the outer peripheral surface of the spool 22.

  The communication path 25 changes the flow path area of the second oil path 18. This change is changed according to the hydraulic pressure of the supply unit 21. That is, the flow area of the second oil passage 18 is increased stepwise from the initial communication state while the spool 22 moves to one side in the reciprocating direction due to the increase in the oil pressure of the second oil passage 18. Here, as described above, the communication path 25 includes a plurality of first communication paths 25A and second communication paths 25B. The flow passage area of the second communication passage 25B is formed to have a flow passage area larger than the flow passage area of the first communication passage 25A. The first communication passage 25A forms an initial communication state. That is, the state in which the supply unit 21 and the discharge unit 24 communicate with each other via the first communication path 25A corresponds to the above-described initial communication state. On the other hand, a state in which the first communication path 25A is fully closed and the supply unit 21 and the discharge unit 24 communicate with each other through the second communication path 25B is referred to as a first communication state (I in the upper part of FIG. 2).

  Here, when the hydraulic pressure supplied to the pressure receiving surface 31 exceeds a predetermined value, the spool 22 is completely retracted so as to be accommodated in the bottom portion 43 of the housing 40 and the side portion 44 of the housing 40. In such a case, the supply unit 21 and the discharge unit 24 communicate with each other without passing through the communication path 25 provided in the spool 22. Such a state is referred to as a second communication state (II in the upper part of FIG. 2). For this reason, according to this flow-path area adjustment part 20, it becomes possible to change the flow-path area in an initial stage communication state in steps to a 1st communication state and a 2nd communication state.

3. Next, the change of the channel area by the channel area adjusting unit 20 will be described with reference to the drawings. FIG. 2 shows a schematic diagram of the operation of the flow channel area adjusting unit 20 and the hydraulic characteristics of the flow channel area adjusting unit 20. FIG. 2 (i) shows an initial state of the hydraulic control device 100. Accordingly, this corresponds to an initial communication state in which the supply unit 21 and the discharge unit 24 communicate with each other through the first communication path 25A. In this state, the oil from the supply unit 21 circulates as shown by the broken line.

  Here, in the upper part of FIG. 2, a hydraulic characteristic is shown in which the horizontal axis represents the rotation speed of the pump 10 and the vertical axis represents the hydraulic pressure of the second oil passage 18. In the state of FIG. 2 (i) described above, the hydraulic pressure in the second oil passage 18 increases according to the rotational speed of the pump 10. This state continues until the rotation speed of the pump 10 reaches T1, the hydraulic pressure of the supply unit 21 is supplied to the pressure receiving surface 31, and the second communication path 25B opens. This state is shown in FIG. 2 (ii). Here, after the spool 22 is maintained in a state in which the flow passage area of the second oil passage 18 is constant during the movement process of the spool 22, a new flow passage is formed through the second communication passage 25B. It is configured as follows. That is, the flow passage area of the second oil passage 18 is maintained at the flow passage area of the first communication passage 25A until the second communication passage 25B opens from the initial communication state. Therefore, a predetermined hydraulic pressure gradient is maintained from the initial communication state until the second communication passage 25B opens.

  When the rotation speed of the pump 10 further increases, the hydraulic pressure of the supply unit 21 increases, and the hydraulic pressure supplied to the pressure receiving surface 31 increases. As a result, a part of the second communication path 25B is in a communication state, but the first communication path 25A maintains the same flow area as the initial communication state immediately after a part of the second communication path 25B is in a communication state. Is configured to do. For this reason, the hydraulic pressure gradient when both the first communication path 25A and the second communication path 25B are in the communication state from the initial communication state can be made gentler than the hydraulic pressure gradient in the initial communication state. The hydraulic pressure gradient when a part of the second communication path 25B is in a communication state can be increased as the flow area of the second communication path 25B is smaller.

  Thereafter, when the oil pressure in the second oil passage 18 increases, as shown in FIG. 2 (iii), the second communication passage 25B is fully opened, and the first communication passage 25A is fully closed. The rotational speed of the pump 10 in this state is T2. The hydraulic pressure gradient immediately after the rotation speed reaches T2 increases as the flow path area formed by the second communication path 25B decreases. In this state, as shown in FIG. 2 (iv), the flow passage area of the second communication passage 25B starts to decrease, and the supply portion 21 and the discharge portion 24 can communicate with each other via the top portion of the spool 22. Continue until.

  Here, after the spool 22 is maintained in a state where the flow passage area of the second oil passage 18 is constant during the movement of the spool 22, a new flow passage is formed through the top of the spool 22. It is configured. That is, the flow area of the second oil passage 18 is further increased in the second communication passage 25B until the rotation speed of the pump 10 further increases and the supply portion 21 and the discharge portion 24 begin to communicate with each other via the top of the spool 22. Maintained in flow area. Therefore, it is possible to make the hydraulic pressure gradient after the new flow path is formed through the top of the spool 22 gentler than the hydraulic pressure gradient maintained in the flow area of the second communication path 25B. Become. At this time, the hydraulic pressure gradient is set by the balance of the flow path area formed by the top part of the spool 22 and the top part 41 of the housing 40 and the flow path area of the second communication path 25B. The inflection of the hydraulic pressure at this time becomes steeper as the flow path area constituted by the second communication path 25B is smaller, and the hydraulic pressure gradient at this time is smaller as the flow path area constituted by the second communication path 25B is smaller. growing.

  Thereafter, until the spool 22 is completely retracted to the bottom portion 43 of the housing 40 and the side portion 44 of the housing 40 (see FIG. 2 (v)), the hydraulic pressure increases with a predetermined hydraulic pressure gradient. When the spool 22 is completely retracted, the hydraulic pressure increases to the discharge capacity of the pump 10. As described above, according to the flow path area adjusting unit 20, even if the rotation speed of the pump 10 fluctuates, the hydraulic pressure is adjusted stepwise as in the first communication state I and the second communication state II shown in FIG. It is possible. Accordingly, oil can be appropriately supplied to the valve timing control device 11A, the turbocharger 11B, the piston jet 11C, and the main gallery 12.

  Thus, according to the hydraulic control apparatus 100, since the plurality of communication paths 25 (25a, 25b) are provided in the spool 22, even when the engine speed changes, the engine speed can be adjusted. Regardless, the hydraulic pressure can be adjusted in a plurality of stages. Therefore, the loss of the pump 10 can be reduced, and the fuel efficiency can be improved.

4). Other Embodiments In the above embodiment, the communication path 25 has been described as a plurality of grooves formed on the outer peripheral surface of the spool 22. However, the scope of application of the present invention is not limited to this. For example, as shown in FIG. 3, the communication passage 25 can be provided as a communication hole 25 that penetrates the spool 22 in the radial direction. A case, since provision of the communication hole 25 between the pressure receiving surface 31 and the back surface 32, the distance between the pressure receiving surface 31 and the back 32, it is preferable to increase as at least communicating hole 25 can be formed. Further, the communication hole 25 can obtain the same characteristics as those formed by the above-described grooves by making the opening area of the first communication hole 25A smaller than the opening area of the second communication hole 25B.

  Further, a recess 91 is formed along the axial direction on the outer peripheral surface of the spool 22 so that the communication hole 25 (opening portion of the communication hole 25) does not deviate from the position facing the supply unit 21 and the discharge unit 24. It is preferable that a convex portion (not shown) that fits into the concave portion is formed on the side portion 42 of 40. Thereby, it can prevent that the spool 22 rotates along an axial center. Even in such a case, the flow path area adjusting unit 20 can appropriately adjust the hydraulic pressure.

  In the above embodiment, the spool 22 is described as being formed with the first communication path 25A and the second communication path 25B. However, the scope of application of the present invention is not limited to this. For example, as shown in FIG. 4, it is also possible to form the three communication paths 25 of the first communication path 25A, the second communication path 25B, and the third communication path 25C in the spool 22. In such a case, the change of the flow path area of the supply unit 21 can be increased in a number of stages. Of course, it is naturally possible to further increase the number of communication passages 25 by four.

  In the above embodiment, the communication passage 25 has been described as changing the flow passage area of the supply unit 21. For example, as shown in FIGS. 5A and 5B, the flow path area is changed by changing the axial length a of the spool 22 of the communication path 25 and the depth b of the communication path 25. Can also be set.

  In the above-described embodiment, the first communication path 25A is configured to maintain the same flow area as that in the initial communication state immediately after a part of the second communication path 25B is in the communication state, and the second communication path 25A. It has been described that the passage 25B is configured to be fully closed when it is fully opened. However, the scope of application of the present invention is not limited to this. The first communication path 25A can be configured to have a smaller flow area than the initial communication state when a part of the second communication path 25B is in the communication state, or the second communication path 25B. It may be configured such that a part is in a communication state when is fully opened.

  The present invention can be used in a hydraulic control device that controls the hydraulic pressure of oil boosted by a pump.

10: Pump 11: First predetermined portion 11A: Valve opening / closing timing control device (VVT)
11B: Turbocharger 11C: Piston jet 12: Main gallery (second predetermined part)
17: 1st oil path 18: 2nd oil path 20: Flow path area adjustment part 21: Supply part 22: Spool 23: Energizing means 24: Discharge part 25: Communication path 25A: 1st communication path 25B: 2nd communication Passage 31: Pressure receiving surface 32: Back surface 100: Hydraulic control device

Claims (3)

A pump that is driven by the rotation of the engine to discharge oil;
A first predetermined portion to which oil discharged from the pump is supplied;
A first oil passage communicating the pump and the first predetermined portion;
A second oil passage provided in communication with the first oil passage and supplying oil to a second predetermined portion different from the first predetermined portion;
A flow that is provided in the second oil passage and increases the flow passage area of the second oil passage by increasing the oil pressure of the second oil passage, and decreases the flow passage area by reducing the oil pressure of the second oil passage. A road area adjustment unit,
The flow path area adjusting unit is
A supply unit to which the oil in the second oil passage is supplied;
A spool having a pressure receiving surface for receiving the oil pressure of the supply unit and a back surface on the back side of the pressure receiving surface , and reciprocating in a direction intersecting the second oil passage to adjust a flow area of the second oil passage; ,
Biasing means for biasing the spool from the back surface toward the pressure receiving surface;
The hydraulic pressure of the second oil passage is communicated with the supply section in an initial communication state until the hydraulic pressure of the second oil passage reaches a predetermined pressure, and the adjusted hydraulic pressure in which the hydraulic pressure of the oil discharged from the pump is adjusted is discharged from the flow path area adjusting section. A discharge section;
The spool is formed in the spool, which increases the flow passage area of the second oil passage in a stepwise manner from the initial communication state while the spool moves to one side in the reciprocating movement direction due to an increase in the oil pressure of the second oil passage. And a plurality of communication passages.   The hydraulic control device according to claim 1, wherein the plurality of communication passages are a plurality of grooves formed on an outer peripheral surface of the spool.   In the spool, a state in which the flow path area of the second oil passage is constant in the movement process of the spool is maintained, and then a new flow path is formed through the plurality of communication paths or the top of the spool. The hydraulic control apparatus according to claim 1, wherein the hydraulic control apparatus is configured to be configured as described above.

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