JP2014214685A - Vehicular oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular oil pump capable of appropriately switching pump capacity according to necessary hydraulic pressure or oil amount.SOLUTION: An oil pump 10 includes a plurality of oil pump mechanisms 20 for sucking and discharging oil; a discharging system 30 in which the oil discharged from the oil pump mechanisms 20 flows; and a drive switching mechanism 50 capable of switching a drive state of the plurality of oil pump mechanisms on the basis of the amount or the hydraulic pressure of the oil drained by a relief valve 34 provided at an intermediate part of the discharging system 30. Under a condition that the hydraulic pressure or the amount of the oil flowing in the discharging system 30 is equal to or higher than a predetermined value, the drive switching mechanism 50 releases the drive of a part of the plurality of oil pump mechanisms 20.

Description

  The present invention relates to a vehicle oil pump used in a vehicle equipped with a transmission such as a continuously variable transmission (CVT) or an automatic transmission (AT).

  Conventionally, in a hydraulic automatic transmission, the original hydraulic pressure is generally secured by an oil pump as disclosed in Patent Documents 1 and 2 below, and the drive of the oil pump depends on the engine output. Yes. In order to improve the fuel consumption of vehicles, which has been a problem in recent years, it has been an object to reduce drive loss caused by a pump in a hydraulic automatic transmission.

JP-A-62-215162 JP-A-1-150250

  Here, various functions are required for the oil pump mounted on the vehicle. Specifically, during a shift transition, it is necessary to operate each clutch piston during a shift within a certain time, and it is necessary to secure a capacity that can cope with flow rate fluctuations. However, such a need for securing the capacity is not always required, and there is a case where the oil flow rate is not so required as in the case where the vehicle is traveling with the shift speed fixed.

  In order to deal with these problems, it is assumed that a regulator is provided to adjust the hydraulic pressure and the oil flow rate to the required amounts, and to return excess oil to the suction side of the oil pump. By adopting such a configuration, the oil discharged from the oil pump can be used as effectively as possible, but the work amount of the oil pump cannot be suppressed to the necessary minimum, and the amount including surplus There is a problem that it is necessary to discharge the oil once.

  Further, in the oil pump disclosed in Patent Document 1, when the oil amount increases more than necessary and the oil pressure increases, the relief valve opens and the oil pressure and oil amount can be adjusted, but the oil pump is driven. Therefore, there is a problem that the fuel consumption is deteriorated. Although the oil pump disclosed in Patent Document 2 has two oil pumps and is configured to be able to release the driving of one oil pump by the centrifugal force of rotation, it is controlled by the number of rotations. Therefore, there is a problem that the pump capacity cannot be adjusted to reflect the required hydraulic pressure or oil amount.

  Accordingly, an object of the present invention is to provide a vehicle oil pump capable of appropriately switching the pump capacity in accordance with the required hydraulic pressure or oil amount.

  The present invention provided to solve the above-described problems is provided with a plurality of oil pump mechanisms for sucking and discharging oil, a discharge system through which oil discharged from the oil pump mechanism flows, and provided in the middle of the discharge system And a drive switching mechanism capable of switching the drive state of the plurality of oil pump mechanisms based on the oil amount or oil pressure of the oil drained in the relief valve provided, and the oil pressure or oil amount of the oil flowing through the discharge system The vehicle oil pump is characterized in that a part of the plurality of oil pump mechanisms is released by the drive switching mechanism on the condition that is equal to or greater than a predetermined value.

  When the above-described configuration is adopted, in a situation where the amount of oil drained in the discharge system and the hydraulic pressure are high, that is, a situation where a high pump capacity (pumping capacity) is required, each oil pump mechanism is driven and the pump capacity is Can be secured. On the other hand, in a situation where the amount of oil drained from the discharge system and the hydraulic pressure are low, that is, a situation where the required pump capacity is not so high, the driving of some oil pump mechanisms is released. As a result, it is possible to suppress useless driving loss while ensuring the necessary minimum pump capacity, and thus contribute to improving the fuel consumption of the vehicle.

  Further, in the vehicle oil pump of the present invention, not the drive control of the pump using the centrifugal force accompanying the rotation as in the oil pump of Patent Document 2 described above, but the oil amount and hydraulic pressure of the oil drained in the discharge system In other words, the control is based on the oil pressure or the oil amount of the pumped oil. Therefore, according to the vehicle oil pump of the present invention, it is possible to perform efficient pump capacity control in consideration of the required hydraulic pressure or pumping oil amount.

  Furthermore, in the vehicle oil pump of the present invention, the drive switching mechanism can be operated based on the oil amount or oil pressure of the oil flowing through the discharge system through the relief valve. Therefore, in the vehicle oil pump of the present invention, an expensive electromagnetic valve or the like is unnecessary, and the manufacturing cost can be suppressed. Further, it is not necessary to perform special control as in the case where an electromagnetic valve is provided.

  In the vehicle oil pump of the present invention described above, the drive switching mechanism includes a hydraulic clutch that is operated by the hydraulic pressure of oil that passes through the relief valve, and the plurality of oil pump mechanisms are coaxially connected to the hydraulic clutch. It is possible to operate the other oil pump mechanism by the driving force transmitted from one oil pump mechanism by connecting adjacent oil pump mechanisms via the hydraulic clutch. The plurality of oil pump mechanisms are connected and operated on the condition that the oil pressure or the amount of oil drained from the discharge system is less than a predetermined value, and the oil is drained from the discharge system. As the oil pressure or oil feed amount increases, the oil pressure or oil feed amount increases as long as the oil pressure or oil amount exceeds a predetermined value. It is desirable that those decoupled from those of the end side among the plurality of the oil pump mechanism.

  In the vehicle oil pump of the present invention, a plurality of oil pump mechanisms are arranged coaxially. Therefore, the vehicle oil pump of the present invention can be a compact device.

  In the vehicle oil pump of the present invention, it is possible to individually set the hydraulic pressure of each hydraulic clutch. With this configuration, it is possible to perform more efficient operation control.

  Further, in the vehicle oil pump of the present invention, the number of oil pump mechanisms driven can be changed according to the oil pressure or the oil amount drained in the discharge system, or the oil pressure or the oil amount of the pumped oil when turned over. it can. Thereby, it becomes possible to contribute to the improvement of the fuel consumption of the vehicle.

  In the vehicle oil pump of the present invention described above, the plurality of oil pump mechanisms are connected so that oil can be discharged to the same discharge system, and the relief valve is provided in the discharge system. It is preferable that it is characterized by this.

  In the vehicle oil pump of the present invention, the amount of oil drained as a surplus in the relief valve can be determined by a relief valve provided in a single discharge system. Therefore, according to the present invention, the vehicle oil pump can be made even more compact and inexpensive.

  ADVANTAGE OF THE INVENTION According to this invention, the oil pump for vehicles which can switch a pump capacity | capacitance appropriately according to required hydraulic pressure or oil quantity can be provided.

It is the conceptual diagram which showed schematic structure of the oil pump which concerns on one Embodiment of this invention. It is a disassembled perspective view of the main pump mechanism and sub pump mechanism which comprise the oil pump of FIG.

  Hereinafter, a vehicle oil pump 10 according to an embodiment of the present invention (hereinafter also simply referred to as “oil pump 10”) will be described in detail with reference to the drawings. As shown in FIG. 1, the oil pump 10 is an automobile pump used in a transmission such as a belt-type continuously variable transmission or an automatic transmission. The oil pump 10 is connected to and driven by a pump drive shaft 12 that is rotated by power transmitted from an engine (not shown), and performs intake and discharge of oil.

  The oil pump 10 includes a plurality of oil pump mechanisms 20, a discharge system 30, and a drive switching mechanism 50. As shown in FIGS. 1 and 2, in the present embodiment, two oil pump mechanisms 20 (hereinafter also referred to as “main pump mechanism 20a” and “sub pump mechanism 20b” as necessary) are provided. The main pump mechanism 20a and the sub pump mechanism 20b have substantially the same configuration, and are arranged side by side on the same axis.

  The oil pump mechanism 20 is a so-called inscribed oil pump mechanism. Specifically, the oil pump mechanism 20 includes an outer gear-like outer gear 14 and an inner gear-like inner gear 16 formed so as to be rotatable while meshing with the outer gear 14. When the inner gear 16 rotates by receiving power, the space volume formed between the outer gear 14 and the inner gear 16 is increased or decreased, and the pump function can be exhibited.

  More specifically, the main pump mechanism 20a and the sub-pump mechanism 20b each have an outer gear-like outer gear 14a, 14b and an inner gear-like shape formed so as to be rotatable while meshing with the outer gear 14a, 14b. Inner gears 16a and 16b.

  The main pump mechanism 20a has a larger capacity than the sub pump mechanism 20b. That is, the oil pump 10 includes a plurality of pump mechanisms having different pump capacities. Specifically, the outer gear 14a and the inner gear 16a forming the main pump mechanism 20a have a larger diameter than the outer gear 14b and the inner gear 16b forming the sub pump mechanism 20b.

  The main pump mechanism 20a is driven by rotating the inner gear 16a using rotational power transmitted from the engine (not shown) side via a torque converter (not shown). Thereby, the oil sucked from the suction port 22a of the main pump mechanism 20a can be discharged from the discharge port 24a.

  The sub pump mechanism 20b can be switched between a connected state and a disconnected state with the main pump mechanism 20a by a hydraulic clutch 52 constituting a drive switching mechanism 50 described in detail later. The sub pump mechanism 20b can be driven in conjunction with the main pump 20a by being connected to the main pump mechanism 20a, and can be stopped by being in a disconnected state. By driving the sub pump mechanism 20b, the oil sucked from the suction port 22b can be discharged from the discharge port 24b.

  A check valve 26 is provided in the discharge port 24b of the sub pump mechanism 20b. Thus, when the sub pump mechanism 20b is in the disconnected state and only the main pump mechanism 20a is operating, the oil discharged from the main pump mechanism 20a side does not flow backward from the discharge port 24b.

  The discharge system 30 is a flow path system through which oil discharged from the main pump mechanism 20a and the sub pump mechanism 20b passes. The discharge system 30 includes a relief valve 34 for adjusting hydraulic pressure in the middle of an oil supply path 32 for supplying discharged oil toward the downstream side. Further, the discharge system 30 has an oil return path 36 for returning the oil drained in the relief valve 34 to the main pump mechanism 20a and the sub pump mechanism 20b side. The oil return path 36 is connected to the suction ports 22a and 22b of the main pump mechanism 20a and the sub pump mechanism 20b, and is also connected to a hydraulic clutch 52 of the drive switching mechanism 50 described in detail later.

  The drive switching mechanism 50 is a switching mechanism for switching the driving state (pump capacity) of the oil pump 10 by switching the main pump mechanism 20a and the sub pump mechanism 20b described above to a connected state or a disconnected state. The drive switching mechanism 50 includes a hydraulic clutch 52 that is operated by hydraulic pressure. The hydraulic clutch 52 is operable between the inner gears 16a and 16b constituting the main pump mechanism 20a and the sub pump mechanism 20b.

  A plurality of (for example, four) hydraulic clutches 52 are provided in the circumferential direction in the inner gear 16a on the main pump mechanism 20a side. The hydraulic clutch 52 includes a piston 54 and a spring 56 that biases the piston 54. The hydraulic clutch 52 is installed so that the piston 54 can advance and retract in the axial direction.

  More specifically, the oil return path 36 of the discharge system 30 described above is connected to the hydraulic clutch 52, and hydraulic pressure can be applied to the chamber opposite to the spring 56 via the piston 54. Yes. Therefore, when the hydraulic pressure acting on the piston 54 via the oil return path 36 is smaller than the urging force by the spring 56, the piston 54 protrudes. On the other hand, when the hydraulic pressure acting on the piston 54 via the oil return path 36 is greater than or equal to the urging force of the spring 56, the piston 54 is retracted.

  The hydraulic clutch 52 can switch the main pump mechanism 20a and the sub pump mechanism 20b between the connected state and the disconnected state by engaging and disengaging the piston 54 with the hole 28 provided on the inner gear 16b side. That is, the inner gears 16a and 16b can be integrally rotated (connected state) by projecting the piston 54 from the main pump mechanism 20a side toward the sub pump mechanism 20b side and inserting it into the hole 28. it can. Further, by retracting the piston 54 from the hole 28, the inner gear 16a can be rotated independently (disconnected state).

  Next, the operation of the oil pump 10 will be described. When the pump drive shaft 12 is rotated by the power transmitted from the engine (not shown) via the torque converter (not shown), the inner gear 16a on the main pump mechanism 20a side is rotated, and the main pump 20a is pumped. Demonstrate the function. Here, in the initial state, the piston 54 of the drive switching mechanism 50 protrudes and engages with the hole 28, and the main pump mechanism 20a and the sub pump mechanism 20b are in a connected state. Therefore, in conjunction with the rotation of the inner gear 16a on the main pump mechanism 20a side, the inner gear 16b on the sub pump mechanism 20b side also rotates, and the sub pump mechanism 20b also exhibits a pump function.

  As described above, the operation of the oil pump 10 is started, and the oil discharged to the oil supply path 32 is regulated by the relief valve 34 and supplied downstream. Here, when the oil pressure or the amount of oil drained to the oil return path 36 side in the relief valve 34 is less than a predetermined value, that is, the oil pressure acting on the hydraulic clutch 52 via the oil return path 36 reduces the biasing force of the spring 56. When it is lower, the main pump mechanism 20a and the sub pump mechanism 20b are connected and operated.

  On the other hand, when the oil pressure or amount of oil drained to the oil return path 36 side is greater than or equal to a predetermined value, that is, when the oil pressure acting on the hydraulic clutch 52 via the oil return path 36 is greater than or equal to the urging force of the spring 56. The piston 54 is detached from the hole 28 formed in the inner gear 16a on the sub pump mechanism 20b side. As a result, the connection between the main pump mechanism 20a and the sub pump mechanism 20b is released, and the driving of the sub pump mechanism 20b located on the end side is stopped. Thereby, the discharge capability as the oil pump 10 whole will be in the state suppressed.

  As described above, the oil pump 10 of this embodiment can drive each oil pump mechanism 20 and ensure the pump capacity in a situation where the amount of oil drained in the discharge system 30 and the oil pressure are high. . On the other hand, in a situation where the oil amount or hydraulic pressure of the oil drained from the discharge system 30 is low and the required pump capacity (discharge amount) is not so large, the drive of the sub pump mechanism 20b is released. Thereby, the required oil discharge amount can be ensured while suppressing the drive loss of the oil pump 10 and contributing to the improvement of the fuel consumption of the vehicle.

  The oil pump 10 controls the cooperative operation of the main pump mechanism 20a and the sub pump mechanism 20b based on the amount of oil drained in the discharge system 30 and the hydraulic pressure. Therefore, according to the oil pump 10, efficient pump capacity control can be performed in consideration of the required hydraulic pressure or pumping oil amount.

  Furthermore, in the oil pump 10, the drive switching mechanism 50 can be operated based on the oil amount and oil pressure of the oil flowing through the discharge system 30 through the relief valve 34, and an electromagnetic valve or the like is not required. Therefore, the oil pump 10 has a low manufacturing cost and does not require special control.

  As described above, in the oil pump 10, the main pump mechanism 20a and the sub pump mechanism 20b are arranged on the same axis. Therefore, the oil pump 10 has a compact device configuration, and can be suitably mounted even in a small vehicle such as a light vehicle or a compact car.

  As described above, in the oil pump 10, the main pump mechanism 20a and the sub pump mechanism 20b are connected to the same discharge system 30. Therefore, the amount of oil drained as a surplus in the relief valve 34 can be determined by the single relief valve 34 provided in the discharge system 30. Therefore, the oil pump 10 is compact and can be manufactured at low cost.

  In the present embodiment, an example in which the two pump mechanisms of the main pump mechanism 20a and the sub pump mechanism 20b are provided as the oil pump mechanism 20 is shown, but the present invention is not limited to this, and there are three It is good also as a structure which provided the above pump mechanism. When three or more pump mechanisms are provided, it is preferable that a hydraulic clutch 52 is provided between the pump mechanisms so that the hydraulic pressure of each hydraulic clutch 52 can be set individually, as described above. . Also, in the case of providing three or more pump mechanisms, it is preferable that the pump mechanisms are arranged on the same axis and are disconnected from the end-side pump mechanism as the amount of hydraulic pressure or oil pressure increases.

  The oil pump of the present invention can be suitably used in a vehicle equipped with a transmission such as a continuously variable transmission (CVT) or an automatic transmission (AT).

DESCRIPTION OF SYMBOLS 10 Oil pump 20 Oil pump mechanism 20a Main pump mechanism 20b Sub pump mechanism 30 Discharge system 34 Relief valve 50 Drive switching mechanism 52 Hydraulic clutch

Claims (3)

A plurality of oil pump mechanisms for sucking and discharging oil;
A discharge system through which oil discharged from the oil pump mechanism flows;
A drive switching mechanism capable of switching a drive state of the plurality of oil pump mechanisms based on an oil amount or oil pressure of oil drained in a relief valve provided in the middle of the discharge system;
The vehicle oil characterized in that a part of the plurality of oil pump mechanisms is released by the drive switching mechanism on condition that the oil pressure or the oil amount of the oil flowing through the discharge system is equal to or greater than a predetermined value. pump. The drive switching mechanism includes a hydraulic clutch that is operated by oil pressure of oil passing through the relief valve;
The plurality of oil pump mechanisms are coaxially arranged via the hydraulic clutch, and the drive transmitted from one oil pump mechanism by connecting adjacent oil pump mechanisms via the hydraulic clutch. The other oil pump mechanism can be operated by force,
Under the condition that the oil pressure or oil amount of oil drained from the discharge system is less than a predetermined value, the plurality of oil pump mechanisms are connected and operated,
On the condition that the oil pressure or oil amount of the oil drained from the discharge system is equal to or greater than a predetermined value, the connection is released from the terminal side of the plurality of oil pump mechanisms as the oil pressure or oil pressure amount increases. The oil pump for vehicles according to claim 1 characterized by things. The plurality of oil pump mechanisms are connected to be able to discharge oil to the same discharge system,
The vehicle oil pump according to claim 1 or 2, wherein the relief valve is provided in the discharge system.

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