JP2017227271A - Oil pressure supply device and pressure regulating valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress pressure oscillation of oil pressure caused by the inertia moment of a second pump and thereby improve the follow-up performance and responsiveness of a feedback pressure to a pilot pressure, while supplying the oil pressure to hydraulic actuation equipment by connecting a first pump normally driven and the second pump driven as necessary in series and in parallel via a check valve.SOLUTION: Oil flowing in a fourth line 4 that is an opening/closing target by a regulator valve 30 is branched out in two directions from a main flow and is caused to act on a valve element 31 in a form of opposing to each other at a second circumferential protrusion 31d of the valve element 31 along the axial direction. The oil acting from a pilot side is caused to pass through an orifice oil passage 31f, that is formed inside the valve element 31 and communicates with an accumulator 80, and to act on the second circumferential protrusion 31d of the valve element 31. On the other hand, the oil acting from a feedback side is caused to directly act on the second circumferential protrusion 31d of the valve element 31.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hydraulic pressure supply device and a pressure regulating valve, and more specifically, hydraulically operates by connecting a first pump that is always driven and a second pump that is driven as necessary in series and in parallel via a check valve. The present invention relates to a hydraulic pressure supply device that supplies hydraulic oil of a predetermined pressure to a device and a pressure regulating valve used in the hydraulic pressure supply device.

  2. Description of the Related Art Conventionally, a mechanical hydraulic pump driven by an engine and an electric hydraulic pump driven by a motor are connected in parallel via a check valve to supply hydraulic oil having a predetermined pressure to hydraulic operating equipment. A hydraulic pressure supply device is known (see, for example, Patent Documents 1 and 2).

  In the hydraulic pressure supply device described in Patent Document 1, a pressure regulating valve is provided between the high pressure circuit and the low pressure circuit, and the oil discharge destination is either the high pressure circuit or the low pressure circuit at the discharge port of the mechanical hydraulic pump. A switching valve for selectively switching is provided on one side. Therefore, when the pressure in the high pressure circuit is higher than the set pressure, the oil related to the excess pressure exceeding the set pressure is supplied to the low pressure circuit via the pressure regulating valve, thereby maintaining the pressure in the high pressure circuit at the set pressure. On the other hand, when the pressure of the high-pressure circuit is lower than the set pressure, the switching valve switches the discharge destination of the first pump from the low-pressure circuit to the high-pressure circuit, and oil is supplied from the first pump to the high-pressure circuit. Is maintained at the set pressure. The switching control of the switching valve is performed while the controller takes in the measurement signal from the pressure sensor.

  On the other hand, in the hydraulic pressure supply device described in Patent Document 2, an abnormality is detected in the electric hydraulic pump while the oil is normally supplied to the high pressure circuit by the electric hydraulic pump, and the oil cannot be supplied to the high pressure circuit. In this case, the oil is supplied to the high-pressure circuit by a mechanical hydraulic pump.

  Further, unlike the above-described hydraulic pressure supply measure, a first pump that is always driven by an engine and a second pump that is driven by a motor are connected in series and in parallel via a check valve, so that a predetermined pressure is applied to the high-pressure circuit. 2. Description of the Related Art A hydraulic pressure supply device that supplies hydraulic fluid with pressure is known (for example, see Patent Document 3).

  In this hydraulic pressure supply device, the discharge port of the first pump is connected to the suction port of the second pump and the high pressure circuit, respectively, and the discharge port of the second pump is connected to the high pressure circuit and the regulator valve, respectively. Therefore, when the driving power of the second pump is small, the first pump supplies oil to both the high pressure circuit and the low pressure circuit. On the other hand, when the driving power of the second pump is large, the second pump sucks oil discharged from the first pump and supplies oil to the high-pressure circuit, while the first pump 10 supplies oil only to the low-pressure circuit. doing.

JP 2010-78087 A JP 2010-139028 A JP2015-200369A

  In the hydraulic pressure supply device described in Patent Document 1, when the required pressure of the high pressure circuit suddenly increases, the controller needs to increase the motor output. In this case, if the pressure is still insufficient even when the motor output is increased, the controller transmits a control signal to the actuator that drives the switching valve to switch the discharge destination of the mechanical hydraulic pump to the high pressure circuit. Thus, in order to supply the hydraulic pressure to the high-pressure circuit, it is necessary to interpose an electrical signal (a measurement signal related to the pressure sensor, a control signal related to the actuator, etc.). That is, there is a problem that it takes time while signals are transmitted, such as hydraulic pressure, electrical signal, and hydraulic pressure, and the required pressure cannot be supplied quickly.

  In addition, when the required flow rate of the high-pressure circuit increases abruptly, the electric hydraulic pump tends to maintain a constant rotation due to the moment of inertia, causing a problem that the pressure of the high-pressure circuit decreases.

  Since the hydraulic pressure supply device described in Patent Document 2 includes a pressure accumulator, it is considered that there is no problem that the pressure of the high pressure circuit decreases when the required flow rate of the high pressure circuit increases rapidly.

  However, when the required pressure of the high pressure circuit increases rapidly, it is necessary to fill the accumulator with energy in order to increase the pressure of the high pressure circuit. Therefore, similarly to Patent Document 1, the hydraulic pressure supply device according to Patent Document 2 has a problem that the required pressure cannot be supplied quickly.

  On the other hand, in the hydraulic pressure supply device described in Patent Document 3, it is not necessary to interpose an electric signal in order to increase the pressure of the high pressure circuit, and it is not necessary to fill the accumulator with energy. Therefore, there is no problem that the required pressure cannot be quickly supplied to the high-pressure circuit.

  FIG. 5 is an explanatory diagram showing a simplified configuration of the hydraulic pressure supply device described in Patent Document 3, and FIG. 6 is an explanatory diagram showing the operation of the hydraulic pressure supply device. Note that only the problem is briefly described here.

  As shown in FIG. 6, during the process of increasing the power of the second pump, from when the check valve is closed to when the regulator valve is out of the pressure regulation state (period from time T2 ′ to T3 ′), or In the process of lowering the power of the second pump, intense pressure vibration is generated in the high-pressure circuit during the period from the time when the regulator valve is adjusted to the time when the check valve is opened (period from time T4 ′ to T5 ′). In order to continuously operate in a region where there is hydraulic vibration, it is necessary to increase the indicated value by the solenoid higher than the actually required pressure so that the oil supply is not insufficient even if there is an amplitude of pressure fluctuation. When the pressure instruction value is increased, the pump torque increases, resulting in a problem that the pump power loss increases. At the same time, there is a problem that followability of the feedback pressure, which is a pressure adjustment target, with respect to the pilot pressure is deteriorated during the period.

  The cause of this hydraulic vibration is that the moment of inertia of the second pump (motor) acts in the direction of reducing the flow rate change, and therefore a time delay occurs when the pressure fluctuation of the discharge pressure of the first pump is transmitted to the high pressure circuit. is there.

  Therefore, the present invention has been made in view of the above-mentioned problems of the prior art, and the object thereof is to connect a first pump that is always driven and a second pump that is driven as necessary via a check valve. Connected in series and in parallel to supply hydraulic pressure (hydraulic oil) to hydraulically operated equipment, while suppressing hydraulic pressure vibration caused by the moment of inertia of the second pump, this makes it possible to follow and respond to the pilot pressure of the feedback pressure. An object of the present invention is to provide a hydraulic pressure supply device that improves the pressure.

  In order to achieve the above object, a hydraulic pressure supply device according to the present invention includes a first pump (10) that is always driven, a second pump (20) that is driven as necessary, and a first pump (10). While narrowing down the pressure adjustment line (4) that is an open / close target that communicates with the discharge port (P11), the pressure balance (PHMD) that is the pressure adjustment target and the pilot pressure (PCMD) that is the pressure instruction value A pressure regulating valve (30) that regulates the feedback pressure to a predetermined pressure, and the first pump (10) and the second pump (20) are connected in series and in parallel via at least one check valve (40). Is a hydraulic pressure supply device that supplies hydraulic pressure to a hydraulically-operated device, wherein the pressure regulating valve (30) includes a valve body (31) having an uneven surface formed on an outer peripheral surface, and a body on which the valve body slides. (32) and the valve body are attached. Configured by a spring (33) that splits oil flowing in the pressure adjusting line (4) in two directions from the main flow, and is opposed along the axial direction at the convex portion (31d) of the valve body (31). In addition, the oil on the pilot side acts so as to be delayed in time from the oil on the feedback side.

  In the above configuration, when the discharge pressure (P10) of the first pump (10) fluctuates from the steady state, the pressure fluctuation component is applied to the first pump (10) separately from the normal feedback pressure (PH) system. It acts directly on the valve body (31) via the pressure regulating line (4) that communicates. The pressure fluctuation component is composed of “a component that changes rapidly with time” and “a component that changes slowly with time”. Therefore, in this case, the pressure fluctuation component acting on the valve body (31) from the pilot side is a “component with a slow time change”. On the other hand, pressure fluctuation components acting on the valve body (31) from the opposite side (feedback side) are both “a component that changes quickly” and “a component that changes slowly”. Accordingly, in the valve body (31), “slowly changing components” cancel each other, and as a result, only “fastly changing components” are directly connected to the valve body (4) from the feedback side via the pressure adjusting line (4). 31).

  That is, in the above configuration, when the discharge pressure (P10) of the first pump (10) fluctuates, the “fluctuating component with high time” (high frequency component) of the pressure fluctuation component passes through the pressure adjustment line (4). It is fed back directly to the valve body (31) with almost no time delay. On the other hand, the “slowly changing component” (low-frequency component) is generated in the normal feedback pressure (PH) system via the second pump (20) while the check valve (40) is closed. It is fed back to the body (31). Thus, when the discharge pressure (P10) of the first pump (10) fluctuates, the pressure fluctuation component is an appropriate time difference for each time change (for each frequency) and the valve element (via a separate system). 31). As a result, the valve body (31) follows the hydraulic pressure fluctuation and stably adjusts the pressure. As a result, pressure vibration, for example, pressure vibration due to the moment of inertia of the second pump (20) does not occur. At the same time, the followability / responsiveness of the feedback pressure to the pilot pressure is improved.

  The second feature of the hydraulic pressure supply device according to the present invention is that the hydraulic pressure area (Φ1) on the feedback side and the hydraulic pressure area (Φ2) on the pilot side of the convex portion (31d) are equal to each other.

  In the above configuration, it is possible to cancel the “slow component of time change” out of the pressure fluctuation components, and to allow only the “component of fast change of time” to act on the valve body (31) directly from the feedback side with almost no time delay. It becomes.

  A third feature of the hydraulic pressure supply device according to the present invention is that, among the oil branched in two directions from the main flow, the pilot-side oil is formed inside the valve body (31), This is to act on the convex portion (31d) of the valve body (31) through the orifice oil passage (31f) whose diameter is partially reduced.

  In the above configuration, the oil acting from the pilot side can be delayed in time from the oil acting from the feedback side. That is, only the “slowly changing component” among the pressure fluctuation components can be selectively passed. As a result, the “slowly changing component” is canceled from the pilot side and the feedback side at the convex portion (31d) of the valve body (31), and only the “fast-changing component” is directly applied to the valve body (31). It is possible to feed back almost without time delay.

  A fourth feature of the hydraulic pressure supply device according to the present invention is that the orifice oil passage (31f) communicates with a pressure accumulator (80).

  In the above configuration, the pressure accumulator (80) can adjust the degree of the time delay of the “slowly changing component” passing through the orifice oil passage (31f). That is, it is possible to adjust the degree of time advance of the “component with fast time change” that is fed back to the valve body (31) via the pressure adjusting line (4) almost without any time delay.

  A fifth feature of the hydraulic pressure supply apparatus according to the present invention is that the hydraulic operating device is a belt type continuously variable transmission mechanism.

  With the above configuration, for example, the belt clamping pressure can be accurately adjusted to the pilot pressure (pressure indication value). As a result, it is possible to reduce excess hydraulic pressure for preventing belt slip. Thereby, pump drive power decreases. Further, the friction loss of the belt is reduced and the power loss due to the pump is also reduced. Therefore, it is possible to reduce the overall power loss.

  In order to achieve the above object, a pressure regulating valve according to the present invention is configured to throttle a pressure regulation line (4) to be opened and closed, while regulating a feedback pressure (PH) to be regulated and a pilot pressure (PCMD) to be a pressure indication value. ) To adjust the feedback pressure to a predetermined pressure, and the pressure adjustment valve (30) includes a valve body (31) having an uneven surface on the outer peripheral surface, The valve body is constituted by a body (32) on which the valve body slides and a spring (33) for biasing the valve body, and the oil flowing in the pressure adjusting line (4) is branched in two directions from the main flow. The convex portion (31d) of (31) is configured so as to face along the axial direction, and is configured such that the pilot-side oil acts with a time delay from the feedback-side oil.

  The above configuration can be suitably applied to the hydraulic pressure supply device.

  The second feature of the pressure regulating valve according to the present invention is that the feedback hydraulic pressure area (Φ1) and the pilot hydraulic pressure area (Φ2) of the convex portion (31d) are equal to each other.

  The above configuration can be preferably applied to the hydraulic pressure supply device having the second feature.

  A third feature of the pressure regulating valve according to the present invention is that, among the oil branched in two directions from the main flow, the pilot-side oil is formed inside the valve body (31), This is to act on the convex portion (31d) of the valve body (31) through the orifice oil passage (31f) whose diameter is partially reduced.

  The above configuration can be preferably applied to the hydraulic pressure supply device having the third feature.

  A fourth feature of the pressure regulating valve according to the present invention is that the orifice oil passage (31f) communicates with a pressure accumulator (80).

  The above configuration can be preferably applied to the hydraulic pressure supply device having the fourth feature.

  According to the hydraulic pressure supply device of the present invention, a first pump that is always driven and a second pump that is driven as necessary are connected in series and in parallel via a check valve, and hydraulic pressure (oil) is supplied to a hydraulically operated device. When the pressure is supplied, the pressure fluctuation component is appropriately fed back to the valve body with an appropriate time difference and through a separate system for each time change. As a result, the valve body follows the fluctuation of the hydraulic pressure and is stably regulated. As a result, pressure vibration, for example, pressure vibration due to the moment of inertia of the second pump does not occur. At the same time, the followability / responsiveness of the feedback pressure to the pilot pressure is improved.

  Therefore, when this hydraulic pressure supply device is applied to a belt-type continuously variable transmission, it is possible to reduce surplus hydraulic pressure for preventing belt slip. As a result, the pump drive power is reduced, and as a result, the overall power loss can be reduced.

It is explanatory drawing which simplified and showed the structure of the hydraulic circuit which concerns on this embodiment. It is principal part cross-sectional explanatory drawing which shows the regulator valve which concerns on this embodiment. It is explanatory drawing which shows the valve position of the regulator valve which concerns on this embodiment. It is a graph which shows operation | movement of this hydraulic circuit. It is explanatory drawing which simplified and showed the structure of the conventional hydraulic circuit. It is explanatory drawing which shows operation | movement of the conventional hydraulic circuit.

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

FIG. 1 is an explanatory diagram showing a simplified configuration of a hydraulic circuit 100 according to the present embodiment.
The hydraulic circuit 100 includes a check valve 40 for the first pump 10 and the second pump 20 with respect to a high-pressure circuit 200 that supplies hydraulic pressure to a pulley mechanism or the like (hydraulic operation device) of a belt type continuously variable transmission (CVT). The hydraulic circuit is connected in series and in parallel to supply hydraulic pressure (oil) stably. In particular, the pressure fluctuation of the hydraulic pressure generated due to the moment of inertia of the second pump 20 (motor M) is suitably suppressed, and the follow-up and response of the feedback pressure to the pilot pressure (pressure indication value) PCMD is improved. Let

  As the configuration of the hydraulic circuit 100, the first line 1 connecting the discharge port P21 of the second pump 20 and the high pressure circuit 200, the discharge port P11 of the first pump 10 and the first line 1 are connected to the check valve 40. The second line 2 connected via the first line 1, the third line 3 branched from the first line 1 and connected to the regulator valve 30, and the fourth branched from the second line 2 and connected to the low pressure circuit 300 via the regulator valve 30. A fifth line 5 that connects the line 4, the discharge port P11 of the first pump 10 and the suction port P22 of the second pump 20, a sixth line 6 that connects the regulator valve 30 and the linear solenoid valve 50, and a regulator A seventh line 7 for connecting the valve 30 and the pressure accumulator 80, an eighth line 8 for connecting the high pressure line 1 and the reducing valve 60, and a linear solenoid valve; A ninth line 9 that connects 0 and the reducing valve 60, a first pump 10 that is always driven by the rotational power of the engine E, a second pump 20 that is driven as required by the rotational power of the motor M, A regulator valve 30 for adjusting the pressure PH of the high-pressure circuit 200 to be equal to the pilot pressure (pressure instruction value PCMD), and a check valve 40 for preventing oil from flowing into the second line 2 from the first line 1 The linear solenoid valve 50 that supplies the pilot pressure to the regulator valve 30, the reducing valve 60 that supplies the original pressure to the linear solenoid valve 50, and the pressure PL of the low-pressure circuit 300 are adjusted to a predetermined pressure (spring load pressure). It comprises a PL regulator valve 70 and an accumulator 80 that absorbs pressure fluctuations of the line pressure. To have. P10 and P20 indicate the discharge pressure of the first pump 10 and the differential pressure of the second pump 20, respectively. Q10 and Q20 indicate the discharge flow rates of the first pump 10 and the second pump 20, respectively.

  For convenience of explanation, an internal system that branches from the fourth line 4 and acts on the valve body 31 from the feedback side and the pilot side is indicated by a bold line portion. Hereinafter, each configuration will be described in more detail.

  The first line 1 is a so-called high pressure line. The first line 1 and the second line 2 are connected at a point C1 in the drawing. Although details will be described later with reference to FIG. 4, oil is initially supplied to the high-pressure circuit 200 via the second line 2 only by the first pump 10. Thereafter, in addition to the first pump 10, the second pump 20 is newly driven, and oil is supplied by using the first pump 10 and the second pump 20 together. Thereafter, when the second pump discharge flow rate Q20 becomes equal to the consumption flow rate QH of the high-pressure circuit 200, the shutoff valve 40 is closed, and oil is supplied to the high-pressure circuit 200 only from the second pump 20.

  The third line 3 is a so-called feedback line. The regulator valve 30 takes in the pressure PH of the high-pressure circuit 200 to be regulated via the third line 3.

  The fourth line 4 is a so-called pressure regulation line (throttle target line) that is opened and closed by the regulator valve 30. When the pressure PH of the high-pressure circuit 200 is higher than the pilot pressure PCMD, the regulator valve 30 operates to regulate the pressure so that the third port P3 opening related to the fourth line 4 is expanded and the pressure PH of the high-pressure circuit 200 is lowered. On the other hand, when the pressure PH of the high pressure circuit 200 is lower than the pilot pressure PCMD, the pressure adjustment operation is performed so as to increase the pressure PH of the high pressure circuit 200 by narrowing the opening of the third port P3 related to the fourth line 4.

  The regulator valve 30 has five ports P1 to P5 on the outside, and has an internal oil passage that communicates the third port P3 and the fourth port P4. Although details will be described later with reference to FIG. 2, the third port P3 and the second port P2 are always in communication via the orifice oil passage 31f. Further, a pressure accumulator 80 is connected to the second port P2 via the seventh line 7. In addition, the first pump discharge pressure P10 is constantly acting on the valve body 31 from both the feedback side and the pilot side. As a result, among the pressure fluctuation components of the first pump discharge pressure P10, components with a slow time change are canceled out, and only the components with a fast time change are fed back directly to the valve body 31 with almost no time delay. That is, when the check valve 40 is in the closed state, the component that changes quickly in the pressure variation component of the first pump discharge pressure P10 is transmitted directly to the valve body 31 via the fourth line 4 with almost no time delay. The component having a slow time change is fed back to the valve body 31 via the fifth line 5, the second pump 20 and the third line 3.

  The check valve 40 is opened only when the first pump discharge pressure P10 is higher than the pressure PH of the high-pressure circuit 200. When the check valve 40 is open and the second pump 20 is in an inoperative state, oil discharged from the first pump 10 is supplied to the high-pressure circuit 200 via the second line 2 and the first line 1. The When the second pump 20 is in an operating state, the oil discharged from the first pump 10 is supplied to the suction port P22 of the second pump 20 via the fifth line 5 in addition to the high-pressure circuit 200.

  On the other hand, when the second pump 20 is driven and the second pump discharge flow rate Q20 becomes equal to the consumption flow rate QH of the high-pressure circuit 200, the check valve 40 is closed.

  In addition, you may provide the check valve which blocks | prevents the inflow of the oil from the high pressure circuit 200 or the 1st pump 10 between the 2nd pump discharge port P21 and the point C1.

  The linear solenoid valve 50 uses the outlet pressure of the reducing valve 60 as a source pressure, adjusts the pressure so as to be equal to the pressure command value (PCMD) by the linear solenoid, and outputs the output value to the regulator valve 30 as a pilot pressure.

  The reducing valve 60 takes the pressure PH of the high-pressure circuit 200 as a source pressure and takes the outlet pressure as a feedback pressure, and adjusts the outlet pressure to be equal to the spring load pressure by balancing the force between the feedback pressure and the spring load pressure. Press.

  The first pump 10 is a positive displacement pump, for example, an internal gear pump. When the first pump 10 is in the unload state, the first pump discharge pressure P10 is regulated by the PL regulator valve 70 so as to be equal to the pressure PL of the low pressure circuit 300.

  The second pump 20 has a linear relationship between the discharge flow rate Q20 and the drive voltage VMOT of the motor M. That is, when the drive voltage VMOT of the motor M is increased linearly, the second pump discharge flow rate Q20 increases linearly, and when the drive voltage VMOT of the motor M is decreased linearly, the second pump discharge flow rate Q20 is increased. Decreases linearly.

  The high-pressure circuit 200 is a hydraulic circuit that supplies hydraulic pressure to a hydraulic operating mechanism such as a CVT pulley mechanism and a CVT forward / reverse switching mechanism (forward clutch, reverse brake). It is composed of a plurality of valves such as a driven pulley regulator valve, a driven pulley linear solenoid, a drive pulley regulator valve, a drive pulley linear solenoid, and a clutch reducing valve, and a plurality of pipes for transferring oil.

  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 cross-sectional view of a main part showing the regulator valve 30 according to the present embodiment. For convenience of explanation, oil passages (third line 3, fourth line 4, seventh line 7, and eighth line 8) connected to each port are also illustrated.

  The regulator valve 30 includes a valve body 31, a body 32, and a spring 33. On the outer peripheral surface of the valve body 31, in order from the left side in the axial direction, a first circumferential convex portion 31a for separating the fourth port P4 and the fifth port P5 (in a non-communication state), a fourth port P4, A circumferential recess 31b that communicates with the 3 port P3, a step portion 31c for narrowing or closing the third port P3, and a second circumference for separating the second port P2 and the third port P3 (to bring them out of communication) A convex portion 31d and a cylindrical portion 31e for accommodating the spring 33 are formed. In addition, an orifice oil passage 31f that always communicates the third port P3 and the second port P2 is formed inside the valve body 31.

  The body 32 is connected to the first port P1 for introducing the pilot pressure (= pressure command value PCMD) via the eighth line 8 and the pressure accumulator 80 via the seventh line 7 in order from the right side in the axial direction. A second port P2 for discharging, a third port P3 for introducing oil discharged from the first pump 10 via the fourth line 4, and a discharge from the first pump 10 via the fourth line 4. A fourth port P4 for flowing the oil flowing through the low pressure circuit 300 and a fifth port P5 for introducing the pressure PH of the high pressure circuit 200 via the third line 3 are formed. Furthermore, a left end portion 32a against which the valve body 31 abuts and a right end portion 32b against which the spring 33 abuts are formed.

  The oil flowing into the third port P3 and flowing out from the fourth port P4 via the circumferential recess 31b (ie, the main flow), that is, the oil discharged from the first pump 10 and supplied to the low pressure circuit 300 (two directions) And partly acts directly on the feedback side of the second circumferential convex part 31d, and partly reflects through the orifice oil passage 31f and is reflected by the pressure accumulator 80 to the pilot side of the second circumferential convex part 31d. Works.

  In particular, the second circumferential convex portion 31d is set so that the outer diameter Φ1 and the outer diameter Φ2 are equal to each other. That is, the feedback hydraulic pressure area S1 and the pilot hydraulic pressure area S2 of the second circumferential convex portion 31d are set to be equal to each other.

  As a result, paying attention to the time change (frequency) of the oil pressure acting on the second circumferential convex portion 31d, the feedback side oil pressure is a mixture of oil pressure having a fast time change (high frequency) and oil pressure having a slow time change (low frequency). On the other hand, the pilot-side hydraulic pressure is a low-frequency hydraulic pressure that changes slowly over time. This is because time delay occurs in the process in which the oil passes through the orifice oil passage 31f and is reflected by the pressure accumulator 80. Therefore, when the hydraulic pressure branched from these mainstreams acts on the second circumferential convex portion 31d at the same time, the hydraulic pressure that changes slowly in time cancels out at the second circumferential convex portion 31d. As a result, among the pressure fluctuation components of the first pump discharge pressure P10, only the hydraulic pressure that changes quickly is fed back directly to the second circumferential convex portion 31d via the fourth line 4 with almost no time delay. .

  In other words, the hydraulic pressure that changes quickly is fed back directly from the first pump 10 to the valve body 31 via the fourth line 4 without any time delay. On the other hand, when the check valve 40 is in a closed state, the oil pressure that changes slowly is fed back to the valve body 31 via the fifth line 5, the second pump 20, and the third line 3. That is, the pressure fluctuation component of the first pump discharge pressure P10 is appropriately fed back to the valve body 31 through a separate system with an appropriate time difference every time change. As a result, the valve body 31 follows the pressure fluctuation and stably regulates the pressure. As a result, the pressure vibration of the high-pressure circuit 200 due to the moment of inertia of the main body of the second pump 20 and the motor M is suppressed. At the same time, the followability / responsiveness of the feedback pressure PH to the pilot pressure PCMD is improved.

  FIG. 3 is an explanatory diagram showing the valve position of the regulator valve 30 according to the present embodiment. Circles in the figure indicate pressure adjustment points.

  At the valve position A, the initial spring load pressure is higher than the pressure PH of the high-pressure circuit 200, and the valve body 31 is pushed by the spring 33 and abuts against the left end portion 32a. In this case, the third port P3 is in a closed state. The first pump 10 communicates with the pressure accumulator 80 via the orifice oil passage 31f. Therefore, the first pump discharge pressure P10 acts on the second circumferential convex portion 31d of the valve body 31 from the feedback side and the pilot side.

  The valve position B is a state immediately after the third port P3 is opened by the step portion 31c. When the pressure PH of the high-pressure circuit 200 exceeds the initial spring load pressure at the valve position A, the valve body 31 starts to move to the right in the axial direction. The third port P3 is opened by the movement of the valve body 31. By opening the third port P <b> 3, the oil discharged from the first pump 10 is drained to the low pressure circuit 300. As a result, the pressure PH of the high-pressure circuit 200 to be regulated is lowered, the valve body 31 moves to the left in the axial direction, and the valve body 31 is balanced at a position where the pressure PH and the pilot pressure PCMD are balanced.

  The valve position C is an explanatory view showing a valve position where the third port P3 is in an open state. When the feedback pressure PH and the pilot pressure are not balanced at the valve position B, the valve body 31 moves to the right in the axial direction to push the third port P3 opening wide.

  The valve position D is a state in which the pressure PH of the high-pressure circuit 200 exceeds the spring load pressure, and the valve body 31 is pushed by the pressure PH and abuts against the right end portion 32b. In this case, the pressure PH of the high-pressure circuit 200 exceeds the pressure regulation limit of the regulator valve 30. Accordingly, the third port P3 is fully opened. Since the first pump 10 and the low pressure circuit 300 are completely in communication with each other, the first pump discharge pressure P10 is adjusted to the low pressure PL by the PL regulator valve 70. The first pump 10 is in an unloaded state.

  When the pressure PH of the high-pressure circuit 200 falls to the pressure regulation range of the regulator valve 30, the valve body 31 starts to move to the left in the axial direction.

  As described above, as the feedback pressure (high-pressure circuit pressure) PH increases, the valve body 31 is balanced around the valve position B and the feedback pressure PH becomes equal to the pilot pressure PCMD while draining oil from the third port P3. Adjust the pressure as follows. Even when the regulator valve 30 drains oil from the third port P3, if the feedback pressure PH increases without being equal to the pilot pressure, the valve body 31 further moves to the right in the axial direction and moves to the third port P2. Push the opening further. If the pressure PH of the high pressure circuit 200 is not equal to the pilot pressure PCMD even when the amount of contraction of the spring 33 is maximized, the third port P3 is fully opened and the first pump 10 is unloaded. In this case, the oil discharged from the first pump discharge pressure P <b> 10 is discharged to the low pressure circuit 300 via the fourth line 4.

  FIG. 4 is a graph showing the operation of the hydraulic circuit 100. The horizontal axis of each graph shows a unified time axis. The vertical axis indicates the high-pressure circuit pressure PH and pressure indication value PCMD, the pump pressures P10 and P20 and the low-pressure circuit pressure PL, the second pump discharge flow rate Q20 and the check valve flow rate Q40, the high-pressure circuit consumption flow rate QH, and the regulator in order from the top. Each time series change of the valve position of the valve 30 is shown. The scale of each vertical axis is a relative value.

  As an operation condition (operation condition), as shown in FIG. 4A, in order to confirm the stability of the hydraulic circuit 100, the pressure command value (pilot pressure) PCMD is changed stepwise. Further, as shown in FIG. 4C, the consumption flow rate QH of the high voltage circuit is changed in a sine wave shape. Further, as partially shown in FIG. 4C, the drive voltage VMOT of the motor M that drives the second pump 20 is linearly raised and lowered. Although not shown, the first pump discharge flow rate Q10 is a constant value.

  As a result of the operation, as shown in FIG. 4A, it can be seen that the high pressure circuit pressure PH is almost equal to the pressure command value (pilot pressure) PCMD. That is, it can be seen that the regulator valve 30 responds quickly to changes in pilot pressure. It can also be seen that the high-pressure circuit pressure PH is stable.

  From time T3 to T4, the high-pressure circuit pressure PH does not follow the pressure command value (pilot pressure) PCMD. This is because the second pump differential pressure P20 increases (the driving power of the motor M increases) and the high-pressure circuit pressure PH exceeds the pressure regulation limit of the regulator valve 30. In this case, the regulator valve 30 is opened (valve position D), and the first pump 10 is unloaded. As a result, as shown in FIG. 4B, the first pump discharge pressure P10 is adjusted to the low pressure circuit pressure PL. The high pressure circuit pressure PH is equal to a value (= P20 + PL) obtained by adding the second pump discharge pressure P20 and the low pressure circuit pressure PL.

  Next, FIG. 4B will be described. From time T0 to T1, the second pump 20 is in an inoperative state. In this case, only the first pump 10 supplies oil to the high-pressure circuit 200. Therefore, the first pump discharge pressure P10 is almost equal (approximate) to the high-pressure circuit pressure PH.

  From time T1 to T2, the second pump 20 is in an operating state, but the second pump differential pressure P20 becomes zero. This is because the oil discharged from the first pump 10 is supplied to the high-pressure circuit via the second line 2, and the differential pressure across the check valve 40 (= second pump differential pressure P20) becomes zero. is there. As a result, the first pump discharge pressure P10 is almost equal (approximate) to the high-pressure circuit pressure PH.

  At time T2, the check valve 40 is closed. Thereby, the relationship of P10 + P20 = PH (= PCMD) is established among the high pressure circuit pressure PH, the first pump discharge pressure P10, and the second pump differential pressure P20. Therefore, when the second pump differential pressure P20 increases from zero from time T2 to T3, the first pump discharge pressure P10 decreases. Conversely, when the second pump differential pressure P20 decreases, the first pump discharge pressure P10 increases.

  In particular, when the consumption flow rate QH (FIG. 4C) of the high pressure circuit 200 increases rapidly, the second pump differential pressure P20 decreases, but the high pressure circuit pressure PH follows the pressure command value (pilot pressure) PCMD. I understand that

  Times T3 to T4 are as described above. Since the pump pressure from time T4 to T6 shows the reverse operation of the pump pressure from time T1 to time T3, description thereof is omitted.

  Next, FIG. 4C will be described. From time T0 to T1, the second pump 20 is in an inoperative state, and only the first pump 10 supplies the high-pressure circuit 200. Therefore, all the oil discharged from the first pump 10 is supplied to the high pressure circuit 200 via the check valve 40. Accordingly, the check valve flow rate Q40 is equal to the consumption flow rate QH of the high-pressure circuit 200.

  At time T1, the second pump 20 starts to be driven. Thereby, the relationship of Q40 + Q20 = QH is established among the consumption flow rate QH, the check valve flow rate Q40, and the second pump discharge flow rate Q20 of the high-pressure circuit 200. As a result, when the second pump discharge flow rate Q20 increases linearly from zero, the check valve flow rate Q40 decreases.

  At time T2, the check valve flow rate Q40 becomes zero (the check valve 40 is closed). Therefore, the relationship of Q40 = 0 and Q20 = QH is established from time T2 to time T5. At time T5, the check valve flow rate Q40 increases from zero (the check valve 40 is open), and the second pump discharge flow rate Q20 decreases linearly.

  FIG. 4D will be described. From time T0 to T3 and from time T4 to T6, the regulator valve 30 performs a pressure adjustment operation so that the high pressure circuit pressure PH becomes equal to the pressure command value (pilot pressure) PCMD in balance with respect to the valve position B. On the other hand, from time T3 to T4 when the second pump differential pressure P20 increases and the high-pressure circuit pressure PH exceeds the pressure regulation limit of the regulator valve 30, the regulator valve 30 balances around the valve position D, and the first Pump 10 is unloaded.

  To summarize the above description, from time T0 to T1, since the motor drive voltage VMOT is zero, the second pump differential pressure P20 and the second pump discharge flow rate Q20 are both zero. As the motor drive voltage VMOT increases, the second pump discharge flow rate Q20 first increases from zero. Since the check valve flow rate Q40 is obtained by subtracting the second pump discharge flow rate Q20 from the consumption flow rate QH of the high-pressure circuit 200, the check valve flow rate Q40 decreases as the second pump discharge flow rate Q20 increases.

  When the check valve flow rate Q40 becomes zero, the check valve 40 is closed, a pressure difference is generated in the second pump 20, and the second pump differential pressure P20 increases. At this time, the second pump discharge flow rate Q20 changes in accordance with the consumption flow rate QH of the high-pressure circuit 200. Since the sum of the first pump discharge pressure P10 and the second pump differential pressure P20 is the high pressure circuit pressure PH, when the second pump differential pressure P20 increases, the first pump discharge pressure P10 decreases and eventually becomes equal to the low pressure circuit pressure PL. Become.

  The first pump 10 is gradually unloaded by the discharge of the second pump 20 after the pressure difference is generated in the second pump 20 until the first pump discharge pressure P10 becomes equal to the low-pressure circuit pressure PL. When the motor drive voltage VMOT decreases, the second pump discharge flow rate Q20 returns to zero by an operation opposite to the increase.

  The regulator valve 30 is pressure-regulated near 1 (valve position B) and opened near 4 (valve position D). 4B, it can be seen that the first pump discharge pressure P10 is higher than the low-pressure circuit pressure PL during pressure adjustment, and the first pump discharge pressure P10 is equal to the low-pressure circuit pressure PL when open. In contrast to FIG. 4A, the high pressure circuit pressure PH and the pressure command pressure (pilot pressure) PCMD are substantially equal during pressure adjustment, and the high pressure circuit pressure PH exceeds the pressure command pressure (pilot pressure) PCMD when opened. I understand.

  As described above, according to the hydraulic circuit 100 of the present invention, the regulator valve 30 quickly responds to the pressure command value (pilot pressure) PCMD so as to adjust the high-pressure circuit pressure PH to be regulated to be equal to the pressure command value PCMD. Operates with pressure.

  Then, when the first pump discharge pressure P10 fluctuates, the component of the pressure fluctuation component whose hydraulic pressure changes quickly is fed back to the valve body 31 via the fourth line 4 almost without any time delay. The component having a slow time change is fed back to the valve body 31 via the fifth line 5, the second pump 20 and the third line 3. That is, the hydraulic pressure fluctuation of the first pump discharge pressure P10 is appropriately fed back to the valve body 31 via a separate system with an appropriate time difference every time change. As a result, the valve body 31 follows the fluctuation of the hydraulic pressure and is stably regulated. As a result, pressure vibration, for example, pressure vibration due to the moment of inertia of the second pump 20 does not occur.

  In addition, the feedback pressure PH that is a pressure adjustment target suitably follows the pressure command value (pilot pressure) PCMD. Therefore, when this hydraulic circuit 100 is applied to a belt-type continuously variable transmission, it is possible to reduce the excess hydraulic pressure for preventing belt slip. As a result, the pump drive power is reduced, and as a result, the overall power loss can be reduced.

1 1st line 2 2nd line 3 3rd line 4 4th line (pressure regulation line)
5 5th line 6 6th line 7 7th line 8 8th line 9 9th line 10 1st pump 20 2nd pump 30 Regulator valve (pressure regulating valve)
40 check valve 50 linear solenoid valve 60 reducing valve 70 PL regulator valve 80 accumulator 100 hydraulic circuit 200 high pressure circuit 300 low pressure circuit

Claims (9)

A first pump that is always driven;
A second pump driven as needed;
The feedback pressure is adjusted to a predetermined pressure by balancing the feedback pressure as the pressure adjustment target and the pilot pressure as the pressure indication value while narrowing the pressure adjustment line as the opening and closing target communicating with the discharge port of the first pump. A pressure regulating valve that presses,
A hydraulic pressure supply device in which the first pump and the second pump are connected in series and in parallel via at least one check valve to supply hydraulic pressure to a hydraulically operated device;
The pressure regulating valve is constituted by a valve body having an uneven surface formed on an outer peripheral surface, a body on which the valve body slides, and a spring that biases the valve body, and the oil flowing in the pressure adjusting line is removed from the mainstream. It is branched in two directions, and is configured such that the oil on the pilot side acts with a time delay from the oil on the feedback side, in a form facing the axial direction at the convex portion of the valve body. Hydraulic supply device.   2. The hydraulic pressure supply device according to claim 1, wherein a hydraulic pressure area on the feedback side and a hydraulic pressure area on the pilot side of the convex portion are equal to each other.   Of the oil branched in two directions from the main flow, the pilot-side oil is formed inside the valve body and passes through an orifice oil passage whose diameter is partially reduced in the cross section of the flow path. The hydraulic pressure supply device according to claim 1, wherein the hydraulic pressure supply device acts on the portion.   The hydraulic pressure supply device according to claim 3, wherein the orifice oil passage communicates with a pressure accumulator.   5. The hydraulic pressure supply device according to claim 1, wherein the hydraulic operating device is a belt type continuously variable transmission mechanism. A pressure regulating valve that regulates the feedback pressure to a predetermined pressure by balancing the force of the feedback pressure to be regulated and the pilot pressure that is the pressure indication value while narrowing the regulation line to be opened and closed,
The pressure regulating valve is constituted by a valve body having an uneven surface formed on an outer peripheral surface, a body on which the valve body slides, and a spring that biases the valve body, and the oil flowing in the pressure adjusting line is removed from the mainstream. It is branched in two directions, and is configured such that the oil on the pilot side acts with a time delay from the oil on the feedback side, in a form facing the axial direction at the convex portion of the valve body. And pressure regulating valve.   The pressure regulating valve according to claim 6, wherein the feedback hydraulic pressure area and the pilot hydraulic pressure area of the convex portion are equal to each other.   Of the oil branched in two directions from the main flow, the pilot-side oil is formed inside the valve body and passes through an orifice oil passage whose diameter is partially reduced in the cross section of the flow path. The pressure regulating valve according to claim 6 or 7, wherein the pressure regulating valve acts on the portion.   The pressure regulating valve according to claim 8, wherein the orifice oil passage communicates with a pressure accumulator.

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