JP2016044806A - Hydraulic supply system changeover mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable hydraulic supply system changeover mechanism in which an effect of reducing driving power of the hydraulic supply system using a plurality of pump systems can be realized to a maximum state, showing less amount of rapid variation of hydraulic pressure at the time of changeover of the pump supply system and less energy loss of working oil at the time of pressure adjustment.SOLUTION: A high pressure branch line 3 and a low pressure branch line 4 branched from each of a high pressure line 1 and a low pressure line 2 are installed in parallel through arrangement of a spool valve 30 at their intermediate location. Then, a pilot pressure 1" determining a pressure in a high pressure circuit 200 is acted while one end of a valve body 31 of the spool valve 30 is being biased by a spring 33 and in turn a line hydraulic pressure 1' at the upstream side of the branch point C1 in the high pressure line 1 is acted on the other end of the valve body 31. Further, an opening edge of the second annular oil passage 31b of the valve body 31 communicating with the high pressure branch line 3 is provided with a recess 31e.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system switching mechanism of a hydraulic supply system, and more specifically, the effect of reducing the driving power of a hydraulic supply system using a plurality of pumps can be maximized and the hydraulic pressure at the time of switching the pump supply system can be drastically reduced. The present invention relates to a system switching mechanism of a highly reliable hydraulic pressure supply system with less energy loss of hydraulic oil during fluctuation and pressure regulation.

Conventionally, as a hydraulic pressure supply system for a hydraulic operating mechanism such as a CVT (belt continuously variable transmission) pulley mechanism, a CVT forward / reverse switching mechanism (forward clutch, reverse brake) or a torque converter lockup clutch mechanism, It has two hydraulic pumps, a first pump that is always connected to a pressure supply path (an oil path that supplies hydraulic oil to the pulley mechanism of the CVT) and a second pump that is provided with a switching valve that switches the supply destination downstream. During normal travel, the switching valve is used to switch the supply destination of the second pump to the main pressure supply oil passage, and the hydraulic oil is supplied to the main pressure supply oil passage by the first pump and the second pump. In this case, the supply destination of the second pump is switched to another system (lubricant supply oil passage) by the switching valve, and only the first pump becomes the original pressure supply oil passage. Hydraulic supply system configured to supply aggressive media (hydraulic control circuit) is known (e.g., FIG. 4 of the cited document 1).
The switching valve that switches the supply destination of the second pump includes a spool, a spring that biases the spool in one direction, and an oil chamber that receives a switching hydraulic pressure output from the switching solenoid valve. When the switching hydraulic pressure is not output, the spool is moved in one direction by the urging force of the spring, and the second pump communicates with the main pressure supply path, and hydraulic oil from the second pump is supplied to the main pressure supply path. When the switching hydraulic pressure is output from the switching solenoid valve, the spool is moved to the other side against the urging force of the spring, the second pump communicates with the lubrication supply oil passage, and the hydraulic oil of the second pump is lubricated. The fact that it is supplied to the supply oil passage is described ([0034] of cited document 1).

JP 2010-190371 A

FIG. 8 is a system diagram of a hydraulic pressure supply system described in the cited document 1 that has a high-pressure pump and a low-pressure pump (solenoid control) and switches the supply destination of the low-pressure pump from a high-pressure circuit to a low-pressure circuit by a boost valve (FIG. 8). FIG. 8A is a flow diagram of hydraulic oil (FIG. 8B). Flow diagram of the hydraulic fluid (FIG. 8 (b)) represented by the horizontal axis consumption rate Q _h of the high-voltage circuit, placed vertically drain flow rate Q _d of the high-pressure relief valve, showing a change in Q _d for Q _h.
For convenience of explanation, it is assumed that the hydraulic supply system is in a state of an operating point A where the total flow rate Q ₁ + Q ₂ of the high pressure pump and the low pressure pump is equal to the consumption flow rate Q _{h of the} high pressure circuit. That is, all of the maximum flow rate Q ₂ of the discharge flow rate of the low pressure pump is supplied to the high pressure circuit, and the flow rate of Q ₁ + Q ₂ is supplied to the high pressure circuit as a whole. “Drain flow rate Q _d ”) is zero. When flow consumption Q _h of the high-pressure circuit is reduced, the high pressure relief valve is opened, the hydraulic supply system shifts from the operating point A to operating point C while excessive operating oil (surplus oil) was discarded through the high pressure branch line ( that is, while reducing high flow rate _{Q h} gradually, drain flow _{Q d} gradually increases.). Then, the boost valve by the solenoid control when reaching the operating point C is opened, the discharge flow rate Q ₂ of the low-pressure pump is supplied to the low-voltage circuit through a low-pressure branch line decreases to result the drain flow rate Q _d is at once the operating point D (Operating point C → operating point D). Further flow consumption Q _h of the high-pressure circuit is reduced from the operating point D, the drain flow rate Q _d of the high-pressure relief valve is gradually increased, the discharge flow rate Q _1, the drain of the high-pressure relief valve of the high-pressure pump when Q _h reaches zero flow rate Q _d is equal operating point E (operating point D → operating point E). When flow consumption Q _h of the high-pressure circuit from the operating point E is gradually increased, the drain flow rate Q _d of the high-pressure relief valve gradually reaches the reduced operating point F (operating point E → operating point F). Reaches the operating point F booster valve by a solenoid control is closed, the discharge flow rate Q ₂ of the low-pressure pump is supplied to the high pressure line, as a result the drain flow rate Q _d is raised to stretch the operation point B (operating point F → operating point B). When flow consumption Q _h of the high pressure circuit increases from operating point B, the drain flow rate Q _d of the high-pressure relief valve decreases gradually and reaches the operation point A (operating point B → operating point A).

By the way, in order to regulate the high voltage circuit, it is necessary to always satisfy Q _d > 0. Ideally, if Q _h <Q ₁ , that is, the boost valve is opened at the operating point G, and conversely, if Q _h > Q ₁ , that is, if the boost valve is closed at the operating point H, then Pressure regulation is performed.
However, in practice, the discharge flow rate to Q ₁ high-pressure pump, and product variation or deterioration in durability of the pump, variations due to viscosity change due to temperature change and aged deterioration of the oil (hereinafter, referred to as "Q ₁ variation".) There is However, since it is necessary to always satisfy Q _d > 0, an actual opening / closing point of the boost valve is considered to be a region smaller than the flow rate Q _{1 of the} high-pressure pump, for example, operating point C and operating point F in consideration of Q ₁ variation. As a result, there is a problem that the frequency of using the low-pressure pump at a low pressure decreases.
In addition, since the booster valve is opened and closed by the solenoid valve in a short time, as shown in FIG. 8B, the flow rate changes suddenly at the operating point C → the operating point D or the operating point F → the operating point B. The accompanying hydraulic oil pressure fluctuation (switching shock) occurred, and as a result, the hydraulic pressure of the pump supply system (high pressure system and low pressure system) became unstable.
Further, the booster valve based on solenoid control has a problem in that it requires a separate drive circuit for energizing the solenoid and a control device for controlling the drive circuit, resulting in poor system reliability.
Therefore, the present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to maximize the driving power reduction effect of a hydraulic supply system using a plurality of systems of pumps. It is an object of the present invention to provide a highly reliable system for switching a hydraulic pressure supply system that is less susceptible to sudden fluctuations in hydraulic pressure during switching of the supply system and less energy loss of hydraulic oil during pressure regulation.

In the system switching mechanism of the hydraulic pressure supply system according to the present invention for achieving the above object, the first discharge port (10a, 10'a) that supplies hydraulic oil to the high-pressure circuit (200) including the hydraulic mechanism that drives the transmission. ), A high pressure line (1) connecting the first discharge port (10a, 10'a) and the high pressure circuit (200), and a low pressure having a lower hydraulic pressure than the high pressure circuit (200) or the high pressure circuit as necessary. A second discharge port (20a, 10'b) for supplying hydraulic oil to the circuit (300) and the high pressure line (7) extending from the second discharge port (20a, 10'b) via a one-way valve (7) 1), a low pressure line (2) connected to the high pressure line (1), a high pressure branch line (3) connected to the low pressure circuit (300) side, and a low pressure line (2) branched from the low pressure line (2). Connected to circuit (300) side That a low-pressure branch line (4), the hydraulic oil in the hydraulic pressure supply system for supplying said the high-voltage circuit (200) or said low-pressure circuit (300),
The high-pressure branch line (3) and the low-pressure branch line (4) are provided in parallel with a common spool valve (30), and the high-pressure circuit (31) is connected to the valve body (31) of the spool valve (30). 200) and a line hydraulic pressure (1 ′) fed back from the high pressure line (1) act on the pilot pressure (1 ″) in the valve body (31), respectively. Only the low pressure branch line (4) is first changed from the closed state to the open state by the balance of the force of the line hydraulic pressure (1 '), and then the high pressure branch line (3) is changed from the closed state to the open state. It is characterized by being.

  In the above configuration, when the flow rate of hydraulic oil supplied to the high pressure circuit (200) by the high pressure pump (10) and the low pressure pump (20) exceeds the consumption flow rate of the high pressure circuit (200), the line hydraulic pressure (1 ′) is The valve body (31) is moved by the balance between the line hydraulic pressure (1 ′) and the pilot pressure (1 ″) in the valve body (31), and is first discharged from the low-pressure pump (20). The low-pressure branch line (4) for discarding the hydraulic oil is opened, excess hydraulic oil is discarded through the low-pressure branch line (4), and pressure regulation for the high-pressure circuit (200) is performed. If pressure regulation for the high pressure circuit (200) is not completed simply by discarding excess hydraulic fluid through the line (4), the valve body (31) is further moved and the high pressure pump (10) The high-pressure branch line (3) for discarding discharged hydraulic oil is opened, excess hydraulic oil is discarded through the high-pressure branch line (3), and pressure regulation for the high-pressure circuit (200) is performed. Thus, even if there is a variation in pump performance or a change in the viscosity of hydraulic oil, the pressure of the low pressure pump (20) depends on the relationship between the consumption flow rate of the high pressure circuit (200) and the discharge flow rate of the high pressure pump (10). Since the oil supply destination is automatically and autonomously switched from the high pressure circuit (200) to the low pressure circuit (300), as described later, the hydraulic oil discharged from the low pressure pump (20) is used in the low pressure state (pump supply). As a result, the energy loss of hydraulic oil during pressure regulation is reduced appropriately, and the drive power reduction effect of the hydraulic supply system using multiple pumps is maximized. In addition, the switching of the supply system of each pump is performed gradually by the balance of the line hydraulic pressure (1 ′) and the pilot pressure (1 ″) in the valve body (31). The switching shock at the time of switching the supply system is reduced. Further, the switching solenoid and the drive circuit are not required, the structure is simplified, and the number of electrical devices is reduced, so that the reliability of the entire system is improved.

  A second feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that the first annular oil passage (31a) that communicates the low pressure branch line (4) with the outer peripheral surface of the valve body (31) and the high pressure. A second annular oil passage (31b) for communicating the branch line (3) is provided independently, and the upstream side of the low-pressure branch line (4) is connected to the body (32) of the spool valve (30). A low-pressure inlet port (32a_in) and a high-pressure inlet port (32b_in) to which the upstream side of the high-pressure branch line (4) is connected are provided independently, and the pilot pressure (1 ") in the valve body (31) and the Only the first annular oil passage (31a) and the low pressure inlet port (32a_in) are changed from the non-overlapping state to the overlapping state by the balance of the force of the line oil pressure (1 '), and then the second annular oil passage (31 b) and the high-pressure inlet port (32b_in) are configured to change from a non-overlapping state to an overlapping state.

  In the above configuration, when both the low pressure branch line (4) and the high pressure branch line (3) are in the closed state, the pilot pressure (1 ″) and the line hydraulic pressure (1 ′) in the valve body (31) As a result of the balance, the low-pressure branch line (4) is first changed from a closed state to an open state, and excess hydraulic oil is discarded through the low-pressure branch line (4), and then the high-pressure branch line (3) is changed from a closed state to an open state. The hydraulic oil is discarded through the high-pressure branch line (3) In this way, the low-pressure branch line (4) and the high-pressure branch line (3) are provided separately and separately, and are sequentially switched from the closed state to the open state. , Do not join directly.

  A third feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that a notch (31e) is provided at an opening edge of the first annular oil passage (31a) or the second annular oil passage (31b). It is being done.

  In the above configuration, the cutout (31e) gradually switches the high-pressure branch line (3) or the low-pressure branch line (4) from the closed state to the open state. It is gradually discarded through the high-pressure branch line (3) or the low-pressure branch line (4), and a rapid change in line oil pressure does not occur at each switching.

  A fourth feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that a notch (31e) is provided at an opening edge of the second annular oil passage (31b), and the valve body (31) Due to the balance between the pilot pressure (1 ″) and the line hydraulic pressure (1 ′), only the first annular oil passage (31a) and the low pressure inlet port (32a_in) are changed from the non-overlapping state to the overlapping state. The notch (31e) and the high-pressure inlet port (32b_in) of the second annular oil passage (31b) are configured to change from a non-overlapping state to an overlapping state.

  In the above configuration, since the notch (31e) gradually switches the high-pressure branch line (3), which is a high-pressure system, from the closed state to the open state gradually, excess hydraulic oil is removed from the high-pressure branch line. It is gradually discarded through (3), and a sudden change in line oil pressure does not occur at the time of switching.

  A fifth feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that the transmission is composed of a continuously variable transmission pulley mechanism, and each pressure regulating valve (DR_REG_V, DN_REG_V) that supplies hydraulic pressure to the pulley mechanism. The higher hydraulic pressure among the driven hydraulic pressures (DRC pressure, DNC pressure) is output from the high pressure circuit (200) as the pilot pressure (1 ″) and acts on the valve body (31). is there.

  In the above configuration, the state in which only the high pressure pump (10) is supplied to the high pressure circuit (200) according to the required flow rate of the high pressure circuit (200) related to the pulley mechanism, and the high pressure pump (10) and the low pressure pump (20) It is possible to suitably switch the state of supplying each discharge to the high voltage circuit (200).

  A sixth feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that the low-pressure circuit (300) comprises a supply destination satisfying the use thereof at a low pressure such as lubrication among the entire circuit system.

  In the above configuration, the gears and the like can be suitably lubricated by using the working oil discarded through the high-pressure branch line (3) and the low-pressure branch line (4).

  A seventh feature of the system switching mechanism of the hydraulic pressure supply system according to the present invention is that the high pressure branch line (3) and the low pressure branch line (4) have the first discharge port (10a) via a relief valve (8). The high pressure pump (10) and the low pressure pump (20) having the second discharge port (20a) are connected to the suction line side connected to the suction line side (6) or the reservoir (9).

  In the above configuration, part of the hydraulic oil discarded through the high-pressure branch line (3) and the low-pressure branch line (4) is supplied to the low-pressure circuit, and the rest is returned to the return line (6) or the reservoir (9). Are returned to the high-pressure pump (10) and the low-pressure pump (20) through the second cycle and reused.

  The eighth feature of the system switching mechanism of the hydraulic pressure supply system of the present invention is that a single pump having a plurality of independent discharge ports that do not communicate with each other (instead of the high pressure pump (10) and the low pressure pump (20)). 10 ′), one discharge port (10′a) is connected to the high pressure line (1), and the other discharge port (10′b) is connected to the low pressure line (2).

  In the above configuration, since the hydraulic oil is supplied to a plurality of systems by a single pump, the driving power for driving the pump is suitably reduced, the hydraulic oil supply system is simplified, and the weight of the entire system is reduced. The

According to the system switching mechanism (100) of the hydraulic pressure supply system of the present invention, when the discharge flow rate of the high pressure pump (10) is larger than the consumption flow rate of the high pressure circuit (200), the discharge destination of the low pressure pump (20) is set to the low pressure circuit (200). 300), and when the discharge flow rate of the high pressure pump (10) is smaller than the consumption flow rate of the high pressure circuit (200), the switching to the high pressure circuit (200) as the discharge destination of the low pressure pump (20) is automatically and autonomously performed. Made. That is, when the operation of the pump is started, the low-pressure branch line (4) of the low-pressure pump (20) and then the high-pressure branch line (3) of the high-pressure pump (10) are connected to the pilot pressure (1 ″) and the line oil pressure (1 By automatically and autonomously switching from the closed state to the open state according to the force balance of '), the supply destination of the low-pressure pump (20) can be controlled regardless of variations in pump performance or fluctuations in oil viscosity. ) To the low pressure circuit (300) or from the low pressure circuit (300) to the high pressure circuit (200) automatically, autonomously and gradually, so that the operation discharged from the low pressure pump (20) The operating area (of the low-pressure branch line (4)) where oil is used in a low pressure state is increased, and as a result, the pump drive power is suitably reduced, and the drive of the hydraulic supply system using a plurality of pumps The power reduction effect can be maximized.
Further, the switching of the hydraulic pressure supply system is gradually performed by the balance of the force of the line hydraulic pressure (1 ′) and the pilot pressure (1 ″) of the high pressure line (1) in the valve body (31). Switching shock during supply system switching is reduced.
Further, the switching solenoid and the drive circuit are not required, the structure is simplified, and the number of electrical devices is reduced, so that the reliability of the entire system is improved.

It is explanatory drawing which shows the system | strain switching mechanism of the hydraulic pressure supply system of this invention. It is explanatory drawing which shows the principal part of the high voltage circuit which concerns on this invention. It is explanatory drawing which shows the flow rate diagram (there is a notch) of the hydraulic pressure supply system which concerns on this invention. It is explanatory drawing which shows the flow rate diagram (there is no notch) of the hydraulic pressure supply system which concerns on this invention. It is explanatory drawing which shows the flow of the hydraulic fluid in each operating point of the hydraulic pressure supply system which concerns on this invention. It is explanatory drawing which shows the state of PH regulator valve | bulb in each operating point of the hydraulic pressure supply system which concerns on this invention. It is explanatory drawing which shows the other example of the system | strain switching mechanism of the hydraulic pressure supply system of this invention. It is explanatory drawing which shows the system | strain switching mechanism of the conventional hydraulic pressure supply system, and its flow rate diagram.

  Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings.

FIG. 1 is an explanatory view showing a system switching mechanism 100 of the hydraulic pressure supply system of the present invention. 1A is an overall system diagram, and FIG. 1B is a cross-sectional view of the main part of a PH regulator valve 30 according to the present invention.
The system switching mechanism 100 of the hydraulic pressure supply system includes a high pressure pump 10 that supplies hydraulic oil to the high pressure circuit 200, a high pressure line 1 that connects the high pressure pump 10 and the high pressure circuit 200, and a high pressure circuit 200 or a low pressure circuit 300 as necessary. A low-pressure pump 20 for supplying hydraulic oil to the high-pressure line, a low-pressure line 2 extending from the discharge port of the low-pressure pump 20 and connected to the high-pressure line 1 via the one-way valve 7, and branched from the high-pressure line 1 and connected to the low-pressure circuit 300 side. The high-pressure branch line 3 (A system), the low-pressure branch line 4 (B system) branched from the low-pressure line 2 and connected to the low-voltage circuit 300 side, and the high-pressure branch line 3 and the low-pressure branch line 4 are coupled to the low-voltage circuit 300. Part of the hydraulic oil discarded through the low-pressure merging line 5 to be connected, the high-pressure branch line 3 and the low-pressure branch line 4 is sucked into the high-pressure pump 10 and the low-pressure pump 20 A return line 6 that returns to the side, a one-way valve 7 that prevents hydraulic oil discharged from the high-pressure pump 10 from flowing into the low-pressure pump 20 side (low-pressure system), a system A, a system B, and a low-pressure merge line 5 Disconnect / connect the low pressure relief valve 8 communicating with the return line 6, the reservoir 9 storing hydraulic oil, and the A system or B system, and discard the hydraulic oil discharged from the high pressure pump 10 or the low pressure pump 20 as necessary. The PH regulator valve 30 to be operated, the line hydraulic pressure line C 1 -C 2 of the high pressure line 1 to act on the PH regulator valve 30, and the signal pressure for adjusting the hydraulic pressure of the high pressure circuit 200. Is provided with a pilot line 1 ″ (pilot hydraulic pressure) for operating the PH regulator valve 30. The system of the present invention. The operation of the switching mechanism 100 will be described later with reference to FIGS. 3-6. In addition, the pilot line 1 "(DRC pressure, DNC pressure) will be described later with reference to FIG. Further, as described above, the high-pressure branch line 3 and the low-pressure branch line 4 may be simply referred to as A system and B system, respectively, as appropriate. Hereinafter, each configuration will be described in more detail.

  The high-pressure pump 10 and the low-pressure pump 20 are positive displacement pumps that are rotationally driven by the engine E / G. The hydraulic oil stored in the reservoir 9 is sucked up, the high pressure pump 10 discharges the hydraulic oil from the first discharge port 10b to the high pressure line 1, and the low pressure pump 20 discharges the hydraulic oil from the second discharge port 20a to the first low pressure line 2.

  The PH regulator valve 30 is a pressure regulating valve including a valve body 31, a body 32, and a spring 33, as shown in FIG. The valve body 31 is subjected to the first annular oil passage 31 a communicating with the low pressure branch line 4, the second annular oil passage 31 b communicating with the high pressure branch line 3, and the above-described line hydraulic pressure flowing between C 1 and C 2 of the high pressure line 1. A pressure receiving surface 31c that performs the above operation and a hollow cylindrical portion 31d on which the pilot pressure acts are provided. Further, a low pressure inlet port 32a_in to which the upstream side of the low pressure branch line 4 is connected, a low pressure outlet port 32a_out to which the downstream side of the low pressure branch line 4 is connected, and an upstream side of the high pressure branch line 3 are connected to the outer peripheral surface of the body 32. A high pressure inlet port 32b_in, a high pressure outlet port 32b_out to which the downstream side of the high pressure branch line 3 is connected, a port 32c to which the line hydraulic pickup line 1 ′ is connected, and a port 32d to which the pilot line 1 ″ is connected. As will be described later, first, the first annular oil passage 31a and the low pressure inlet port 32a_in are switched from the non-overlapping state to the overlapping state, the A system is changed from the closed state to the open state, and then the second annular oil passage 31b and the high pressure The inlet port 32b_in is switched from the non-overlapping state to the overlapping state, and the B system is changed from the closed state to the open state.

PH against valve body 31 of the regulator valve 30, the elastic force, "the pilot pressure P ₁ to be subjected _to" pilot line _1, the 'line pressure P ₁ to be subjected _to' line pressure pickup line 1 action of the spring 33 Normally, however, the valve body 31 is stationary at a position where these three forces are balanced. However, for example, the flow rate of the high-pressure circuit 200 decreases, the line hydraulic pressure P _{1 ′} rises and the balance of these three forces breaks, and as a result, the first annular oil passage 31 a is opened and the low-pressure branch line 4 The hydraulic oil flows into the first annular oil passage 31a. In this case, the hydraulic oil flowing in from the low-pressure branch line 4 flows out from the low-pressure outlet port 32a_out and is provided downstream of the low-pressure branch line 4.

Subsequently, the balance between the line hydraulic pressure P _{1 ′} , the elastic force of the spring 33 and the force of the pilot pressure P _{1 ″} collapses. As a result, when the second annular oil passage 31b is opened, the hydraulic oil from the high-pressure branch line 3 is discharged. In this case, the hydraulic oil flowing in from the high pressure branch line 3 flows out of the high pressure outlet port 32b_out and is provided downstream of the high pressure branch line 3.

  The one-way valve 7 prevents the hydraulic oil from flowing from the high pressure line 1 to the low pressure line 2, but permits the hydraulic oil to flow from the first low pressure line 2 to the high pressure line 1. That is, the one-way valve 7 prevents the high pressure system hydraulic pressure from directly flowing into the low pressure system hydraulic pressure.

  When the hydraulic pressure of the low pressure circuit 300 exceeds a preset value, the low pressure relief valve 8 communicates the A system, the B system, the low pressure merging line 5 and the feedback line 6, and a part of the hydraulic oil is returned to the feedback line 6. Destroy. The discarded hydraulic oil is returned to the suction port side or the reservoir 9 of the high-pressure pump 10 and the low-pressure pump 20 and supplied again to the high-pressure line 1 or the first low-pressure line 2.

  The high-voltage circuit 200 is hydraulically applied to a hydraulic operating mechanism such as a CVT (belt continuously variable transmission) pulley mechanism, a CVT forward / reverse switching mechanism (forward clutch, reverse brake), or a torque converter lockup clutch mechanism. Is a hydraulic circuit for supplying

  The low-pressure circuit 300 is a supply destination satisfying the use at a low pressure such as lubrication in the entire circuit system, for example, a lubrication circuit, a heat exchanger, and an oil filter.

  FIG. 2 is an explanatory diagram showing a main part of the high-voltage circuit 200 according to the present invention. The description and illustration here are limited to the hydraulic circuit related to the drive pulley mechanism 200DR and the driven pulley mechanism 200DN related to the pilot line 1 ″, and other forward / reverse switching mechanisms and a lock-up mechanism of the torque converter. The description and illustration of the hydraulic circuit according to the above are omitted.

  The hydraulic oil discharged from the high-pressure pump 10 or the like and supplied to the high-pressure circuit 200 via the high-pressure line 1 flows through the PH line PH_L, and then the PH pulley line PH_PL that drives the drive pulley mechanism 200DR and the driven pulley mechanism 200DN, DR The pressure control valve DR_REG_V and the DN pressure control valve DN_REG_V, and the DR control valve DR_CTL_V and the DN control valve DN_CTL_V are branched into two systems, namely, a PH valve line PH_VL.

  First, the hydraulic oil branched to the PH valve line PH_VL flows through the CR line CR_L while being reduced to the CR pressure by the pressure reducing valve CR_V, and then branched into two systems, the CR drive line CR_DRL and the CR driven line CR_DNL, and the DR control valve The DRC pressure and the DNC pressure are respectively regulated by the DR_CTL_V and the DN control valve DN_CTL_V, and the DRC pressure and the DNC pressure are respectively supplied to the DR pressure regulating valve DR_REG_V and the DN pressure regulating valve DN_REG_V via the DRC line DRC_L and the DNC line DNC_L. One end of the spool of DR control valve DR_CTL_V and DN control valve DN_CTL_V is energized by DR solenoid valve DR_SOL_V and DN solenoid valve DN_SOL_V, respectively, and the DNC pressure and DRC pressure of hydraulic oil are controlled by the thrust (energization amount) of each solenoid. Is done.

  On the other hand, the hydraulic oil branched to the PH pulley line PH_PL is further branched into two systems, a drive pulley line PH_P_DRL and a driven pulley line PH_P_DNL, and adjusted to a DR pressure and a DN pressure by a DR pressure regulating valve DR_REG_V and a DN pressure regulating valve DN_REG_V, respectively. And supplied to the drive pulley mechanism 200DR and the driven pulley mechanism 200DN via the DR line DR_L and the DN line DN_L, respectively, and the drive pulley 200DR and Each side pressure of the driven pulley 200DN is increased or decreased to control the gear ratio.

  The DRC pressure and the DNC pressure that drive the DR pressure regulating valve DR_REG_V and the DN pressure regulating valve DN_REG_V are supplied to the PH shift valve PH_SHIFT_V adjacent to the PH regulator valve 30, and the DR shift pressure PH_SHIFT_V includes the DRC pressure and the DNC pressure. The higher hydraulic pressure is output to the pilot line 1 ″ as the PH pilot pressure and acts on one end of the valve body 31 of the PH regulator valve 30.

3 and 4 are explanatory views showing a flow diagram of a hydraulic pressure supply system according to the present invention, the flow consumption Q _h of the horizontal axis high-voltage circuit 200, the drain flow rate Q _d1 from the vertical axis A strains, A drain flow rate Q _d2 from the B system, a low pressure circuit supply flow rate, a high pressure pump discharge pressure, and a low pressure pump discharge pressure are shown. Q ₁ indicates the discharge flow rate of the high-pressure pump 10, and Q ₂ indicates the discharge flow rate of the low-pressure pump 20. FIG. 3 shows the case with the notch 31e, and FIG. 4 shows the case without the notch 31e.

At the operating point A ′ in FIG. 3B, the consumption flow rate Q _h of the high pressure circuit 200 is equal to the sum of the discharge flow rate Q ₁ of the high pressure pump 10 and the discharge flow rate Q ₂ of the low pressure pump 20. Since the discharge flow rates of the two pumps all flow into the high pressure circuit 200, the drain flow rate Q _d1 from the A system and the drain flow rate Q _d2 from the B system are both zero, and the supply flow rate to the low pressure circuit 300 is also zero. . At the operating point A ′, the A system (high pressure branch line 3) and the B system (low pressure branch line 4) are both closed, and the PH regulator valve 30 is in the state shown in FIG. That is, the low pressure inlet port 32a_in and the high pressure inlet port 32b_in are both closed by the valve body 31, and the first annular oil passage 31a and the low pressure inlet port 32a_in and the second annular oil passage 31b and the high pressure inlet port 32b_in are both non-overlapping. .

Returning to FIG. 3B, from the operating point A ′ to the operating point B ′, the drain flow rate Q _{d2 of the} hydraulic oil discarded from the B system increases from zero. That is, as shown in FIG. 6 (a), the valve body 31 moves to the right due to the line hydraulic pressure of the hydraulic pickup line 1 ′, and the low pressure inlet port 32a_in and the first annular flow path 31a overlap, resulting in the B system (low pressure). The branch line 4) is gradually opened, and as shown in FIG. 5 (b), a part of the hydraulic oil (drain flow rate Q _d2 ) discharged from the low pressure pump 20 flows to the low pressure circuit 300 through the B system. Note that the one-way valve 7 is still in an open state, and therefore, Q ₂ -Q _d2 excluding the drain flow rate Q _{d2 out} of the discharge flow rate Q ₂ of the low pressure pump 20 is supplied to the high pressure line 1, and as a whole the high pressure The circuit 200 is supplied with hydraulic fluid of Q ₁ + Q ₂ −Q _d2 = Q _h , and the low pressure circuit 300 is supplied with hydraulic fluid of Q _d2 . In particular, from the operating point A ′ to the operating point B ′, the pressure adjustment to the high-pressure circuit 200 and the supply of the operating oil to the low-pressure circuit 300 are performed only by the operating oil discarded from the B system (low-pressure pump 20).

Returning to FIG. 3B, the inclination angle of the drain flow rate _Qd2 changes from the operating point B ′ to the operating point C ′. As shown in FIG. 6 (b), when the valve body 31 further moves to the right and the B system is opened about half, the high pressure inlet port 32b_in and the notch 31e of the valve body 31 begin to overlap. This is because the A system (the high-pressure branch line 3) is in an open state. As shown in FIG. 5C, the drain flow rate Q _d1 > 0. In particular, as shown in FIG. 3A, due to the effect of the notch 31e, the rising angle of the drain flow rate Q _d1 when the system A is in an open state becomes dull, and as a result, the inclination angle of the drain flow rate Q _d2 is also reduced. As a result, sudden flow fluctuations (pressure fluctuations) are suppressed. Further, from the operating point B ′ to the operating point C ′, both the A system and the B system are in an open state, and therefore the high-pressure circuit 200 has a hydraulic oil of Q ₁ + Q ₂ −Q _d1 −Q _d2 = Q _h . Is supplied, and hydraulic fluid of Q _d1 + Q _d2 is supplied to the low pressure circuit.

In the operating point C ', the one-way valve 7 is closed, all flow Q ₂ to which is discharged from the low-pressure pump 20 is supplied to the B lineage (low pressure branch line 4). In this case, since the hydraulic oil discharged from the low pressure pump 20 is not supplied to the high pressure line 1, the flow rate of Q ₁ −Q _d1 = Q _h is supplied to the high pressure circuit 200 as a whole, and Q ₂ + Q is supplied to the low pressure circuit 300. _d1 hydraulic oil is supplied. Further, as shown in FIG. 3 (e), the discharge pressure of the low-pressure pump 20 starts to decrease at the operating point C ′.

Returning to FIG. 3 (b) again, from the operating point C ′ to the operating point D ′, the drain flow rate Q _d2 shows a constant value (Q ₂ ) for the B system, while shown in FIG. Thus, the drain flow rate Q _d1 of the A system is increased. That is, for the B system while all the flow Q ₂ to which is discharged from the low-pressure pump 20 is supplied to the low pressure circuit 300, the system A is proportional to the degree of overlap between the high pressure inlet port 32b_in a second annular channel 31b The drain flow rate Q _d1 is supplied to the low-pressure circuit 300, and the pressure regulation for the high-pressure circuit 200 is performed only by the A system. The PH regulator valve 30 is in the state shown in FIG. That is, the low pressure inlet port 32a_in is opened widely, and the discharge pressure of the low pressure pump 20 is obtained by adding the pressure difference between the low pressure inlet port 32a_in and the low pressure outlet port 32a_out to the opening pressure of the low pressure relief valve 8. The high pressure circuit 200 is supplied with hydraulic oil Q ₁ -Q _{d 1} , and the low pressure circuit 300 is supplied with hydraulic oil Q ₂ + Q _{d 1} . In this section, the low-pressure pump is used at a low pressure, so the driving power of the low-pressure pump is small.

Incidentally, if the required flow rate Q _h of the high-voltage circuit 200 exceeds the discharge flow rate of the high pressure pump 10, the reverse process, namely through the operating point D '→ operating point C' → operating point B '→ working point A', Each hydraulic pressure supply system of the high-pressure pump 10 and the low-pressure pump 20 is gradually and automatically and autonomously switched from the low-pressure circuit 300 to the high-pressure circuit 200, thereby maintaining the supply capability to the high-pressure circuit 200.

  Further, as shown in FIG. 4, when there is no notch 31e, the high-pressure circuit 200 is regulated by the A system particularly in an operating condition where the rotational speed of the pump drive shaft is small and the viscosity of the hydraulic oil is low. Between the position range of the valve body 31 and the position range of the valve body 31 in which the pressure of the high-pressure circuit 200 is regulated by the B system, a range in which pressure regulation is not performed by either system is generated. When passing through this range, the pressure of the high-pressure circuit 200 may change unintentionally. On the other hand, when there is no notch 31e, there is no area between the operating point B ′ and the operating point C ′ in FIG. Can be small.

FIG. 7 is an explanatory view showing another example of the system switching mechanism of the hydraulic pressure supply system of the present invention.
In the above-described system switching mechanism 100 of the hydraulic supply system, a high pressure pump (10) and a low pressure pump (20) are separately provided to the high pressure line 1 and the low pressure line 2, respectively. The low pressure pump (2) supplies hydraulic oil to the low pressure line 2 respectively. On the other hand, the system switching mechanism 100 ′ of this hydraulic pressure supply system is configured to supply hydraulic oil to the high pressure line 1 and the low pressure line 2 by a single pump, respectively. That is, a single pump 10 'includes a plurality of non-communicating discharge ports 10'a and 10'b, one discharge port 10'a going to the high pressure line 1 and the other discharge port 10'b being the low pressure line 2. Are connected to the high pressure line 1 or the low pressure line 2 independently of each other. As a result, the driving power for driving the pump is suitably reduced, the hydraulic oil supply system is simplified, and the weight of the entire system is reduced. In addition, the configuration other than the pump is the same as that of the system switching mechanism 100 of the hydraulic pressure supply system.

As described above, according to the system switching mechanisms 100 and 100 ′ of the hydraulic pressure supply system of the present invention, when the discharge flow rate of the high pressure pump 10 is larger than the consumption flow rate of the high pressure circuit 200, the discharge destination of the low pressure pump 20 is the low pressure circuit 300. When the discharge flow rate of the high pressure pump 10 is smaller than the consumption flow rate of the high pressure circuit 200, the switching of the discharge destination of the low pressure pump 20 to the high pressure circuit 200 is automatically and autonomously performed. That is, when the operation of the pump is started, the pressure of the high pressure circuit 200 is increased, and the balance between the line hydraulic pressure 1 ′ and the pilot pressure 1 ″ is superior to that of the line hydraulic pressure 1 ′. The valve body 31 moves to the right, and the low-pressure branch line 4 (B system) is opened to the state shown in Fig. 6 (a) On the other hand, if the discharge flow rate of the high-pressure pump 10 is smaller than the consumption flow rate of the high-pressure circuit 200, 6A, the high pressure branch line 3 (A system) is closed and the pressure of the high pressure circuit 200 is adjusted by changing the valve clearance of the low pressure branch line 4 (B system). The discharge pressure of the low pressure pump 20 is a pressure obtained by adding the valve opening pressure of the one-way valve 7 to the pressure of the high pressure circuit 200. When the discharge flow rate of the high pressure pump 10 is larger than the consumption flow rate of the high pressure circuit 200, the low pressure branch line. 4 (B system) valve clearance increased, The one-way valve 7 is closed.Next, the pressure of the high-pressure circuit 200 is increased by the discharge of the high-pressure pump 10, and the valve body 31 in FIG. The position of the moving valve body 31 is as shown in FIG. 6C, and the pressure of the high-pressure circuit 200 is adjusted by changing the valve clearance of the high-pressure branch line 3 (A system). At this time, since the discharge pressure of the low pressure pump 20 is the pressure of the low pressure circuit 300, the driving power of the low pressure pump 20 can be reduced. For this reason, the operating region in which the hydraulic oil discharged from the low pressure pump (20) is used in a low pressure state (in the low pressure branch line (4)) is increased. As a result, the pump driving power is suitably reduced, and a plurality of pumps are used. The driving power reduction effect of the hydraulic supply system that has been used can be maximized.
Further, the switching of the hydraulic pressure supply system is gradually performed by the balance of the force of the line hydraulic pressure 1 ′ and the pilot pressure 1 ″ from the high pressure line 1 applied to the valve body 31. Is reduced.
Further, the switching solenoid and the drive circuit are not required, the structure is simplified, and the number of electrical devices is reduced, so that the reliability of the entire system is improved.

DESCRIPTION OF SYMBOLS 1 High pressure line 2 Low pressure line 3 High pressure branch line 4 Low pressure branch line 5 Low pressure junction line 6 Return line 7 One-way valve 8 Low pressure relief valve 9 Reservoir 10 High pressure pump 20 Low pressure pump 30 PH regulator valve 31 Valve body 31a First annular oil passage 31b Second annular oil passage 31e Notch 32 Body 100, 100 ′ System switching mechanism 200 of hydraulic pressure supply system High pressure circuit 300 Low pressure circuit

Claims (8)

A first discharge port that supplies hydraulic oil to a high-pressure circuit including a hydraulic mechanism that drives the transmission, a high-pressure line that connects the first discharge port and the high-pressure circuit, and the high-pressure circuit or the high-pressure circuit as necessary. A second discharge port for supplying hydraulic oil to a low pressure circuit having a low hydraulic pressure; a low pressure line extending from the second discharge port and connected to the high pressure line via a one-way valve; and branching from the high pressure line to the low pressure circuit side A high pressure branch line connected to the low pressure line and a low pressure branch line connected to the low pressure circuit side and supplying hydraulic oil to the high pressure circuit or the low pressure circuit,
The high-pressure branch line and the low-pressure branch line are provided in parallel to a common spool valve, and a pilot pressure that determines the pressure of the high-pressure circuit with respect to the valve body of the spool valve and a line fed back from the high-pressure line Each of the hydraulic pressures acts, and due to the balance between the pilot pressure and the line hydraulic force in the valve body, only the low-pressure branch line is changed from the closed state to the open state, and then the high-pressure branch line is changed from the closed state to the open state. It is comprised so that it may become. The system | strain switching mechanism of the hydraulic supply system characterized by the above-mentioned.   A first annular oil passage that communicates with the low-pressure branch line and a second annular oil passage that communicates with the high-pressure branch line are separately provided on the outer peripheral surface of the valve body, and the body of the spool valve A low-pressure inlet port to which the upstream side of the low-pressure branch line is connected and a high-pressure inlet port to which the upstream side of the high-pressure branch line is connected are provided independently, and by the balance between the pilot pressure applied to the valve body and the line hydraulic force First, only the first annular oil passage and the low pressure inlet port are changed from the non-overlapping state to the overlapping state, and then the second annular oil passage and the high pressure inlet port are changed from the non-overlapping state to the overlapping state. The system switching mechanism of the hydraulic pressure supply system according to claim 1, wherein   The system switching mechanism of the hydraulic pressure supply system according to claim 2, wherein a notch is provided in an opening edge portion of the first annular oil passage or the second annular oil passage.   A notch is provided at the opening edge of the second annular oil passage, and only the first annular oil passage and the low-pressure inlet port are first brought about by the balance between the pilot pressure applied to the valve body and the line oil pressure. The non-overlapping state is changed to the overlapping state, and the notch and the high-pressure inlet port of the second annular oil passage are subsequently changed from the non-overlapping state to the overlapping state. System switching mechanism of the hydraulic supply system.   The transmission comprises a continuously variable transmission pulley mechanism, and the higher hydraulic pressure among the hydraulic pressures that drive the pressure regulating valves that supply hydraulic pressure to the pulley mechanism is output from the high pressure circuit as the pilot pressure. The system switching mechanism of the hydraulic pressure supply system according to claim 1, wherein the system switching mechanism acts on the valve body.   2. The system switching mechanism of a hydraulic pressure supply system according to claim 1, wherein the low-pressure circuit is a lubrication circuit, a heat exchanger, an oil filter, or the like, which is a supply destination that satisfies its use at a lower pressure than the high-pressure circuit. .   The high-pressure branch line and the low-pressure branch line are connected via a relief valve to a feedback line or a reservoir connected to each suction port side of the high-pressure pump having the first discharge port and the low-pressure pump having the second discharge port. The system switching mechanism of a hydraulic pressure supply system according to any one of claims 1 to 6, wherein   Instead of the high-pressure pump and the low-pressure pump, a single pump having a plurality of independent non-communicating discharge ports is used, one discharge port to the high-pressure line, and the other discharge port to the low-pressure line. The system switching mechanism of the hydraulic pressure supply system according to claim 7, wherein each is connected.

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