JP2014025514A - Lubrication circuit of speed changer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubrication circuit of a speed changer, capable of preventing a lubricant from being supplied to a lubrication unnecessary part when a hydraulic pressure is low without increasing a variable resistance part.SOLUTION: A lubrication circuit 1 includes a base part oil passage 3 in which a lubricant supplied from a pump 21 through a pressure control valve 22 is allowed to flow, a first oil passage 4 communicated to the base part oil passage 3 to guide the lubricant to a first lubrication part 81, a branched passage 5 branched from the base part oil passage 3 in a height direction, and a second oil passage 6 communicated to an upper end part of the branched passage 5 to guide the lubricant to a second lubrication part 82. The height of the branched passage 5 is set to a height allowing the lubricant to be supplied to the first lubrication part 81 through the first oil passage 4 without supplying the lubricant to the second lubrication part 82 when an oil pressure of the lubricant supplied from the pressure control valve 22 is less than a predetermined pressure, and allowing the lubricant to be supplied also to the second lubrication part 82 through the branched passage 5 and the second oil passage 6 when the oil pressure of the lubricant supplied from the pressure control valve 22 is the predetermined pressure or more.

Description

  The present invention relates to a lubricating circuit that supplies lubricating oil to a portion of a transmission that requires cooling or lubrication.

  2. Description of the Related Art Conventionally, there has been known a lubrication circuit in which a part of lubricating oil used in a hydraulic circuit is supplied to a heat generating portion of a transmission or a portion requiring lubrication to perform cooling or lubrication (see, for example, Patent Document 1). In Patent Document 1, the lubricating oil regulated by the pressure regulating valve is further depressurized via an orifice, a choke or the like, and supplied to a portion requiring cooling or lubrication.

Japanese Patent No. 4899070

  In the conventional lubrication circuit of the transmission, even when the pressure of the lubricating oil is low, such as during idle neutral control, the lubricating oil is supplied to the portions that do not require lubrication. For this reason, the conventional lubrication circuit has a problem that a large amount of lubricating oil is supplied even to a portion that does not require lubrication in order to supply sufficient lubricating oil to a portion that requires lubrication.

  In order to solve this problem, it is conceivable to provide a variable resistance part such as an electromagnetic valve so that lubricating oil is not supplied to the part of the transmission that does not require lubrication when the hydraulic pressure is low. Manufacturing cost will increase.

  In view of the above, the present invention provides a lubrication circuit for a transmission that can prevent lubricating oil from being supplied to a portion that does not require lubrication when the hydraulic pressure is low, without adding a variable resistance unit such as a solenoid valve. The purpose is to provide.

  [1] In order to achieve the above object, a lubrication circuit for a transmission according to the present invention includes a base oil passage through which lubricating oil supplied from a hydraulic control unit flows, and a base oil passage that lubricates the first lubricating portion. A first oil passage that guides oil; a branch passage that branches from the base oil passage in a height direction; and a second oil passage that communicates with an upper end portion of the branch passage and guides the lubricating oil to a second lubricating portion. The height of the branch path is such that when the hydraulic pressure of the lubricating oil supplied from the hydraulic control unit is less than a predetermined pressure, the lubricating oil is supplied to the first lubricating unit via the first oil path, When no lubricating oil is supplied to the second lubricating portion and the hydraulic pressure of the lubricating oil supplied from the hydraulic pressure control portion is equal to or higher than a predetermined pressure, the second lubricating portion is provided via the branch passage and the second oil passage. Further, the height is set to a height at which the lubricating oil is supplied.

  According to the present invention, when the hydraulic pressure of the lubricating oil flowing through the base oil passage is less than a predetermined pressure, the first lubricating portion is lubricated, but the supply of the lubricating oil to the second lubricating portion is caused by the action of the branch passage. Be blocked. Therefore, by setting the first lubrication portion as a portion that requires lubrication and setting the second lubrication portion as a portion that does not require lubrication, in order to ensure the lubrication amount of an arbitrary portion of the transmission, at low pressure, It is possible to prevent a large amount of lubricating oil from being supplied to a lubricating portion that is not necessary. Thereby, useless energy consumption of the hydraulic control unit can be suppressed, and the fuel efficiency of the vehicle can be improved.

  [2] In the present invention, the hydraulic control unit includes a pump that is operated by a drive source of the vehicle, and the first lubrication unit is in a start state in which the vehicle shifts from a stop state to a start state. The second lubrication portion may be a portion that requires lubrication in a traveling state other than the starting state.

  According to the present invention, when the vehicle is in a stopped state, the hydraulic pressure is set to be less than a predetermined pressure by the hydraulic pressure control unit, so that the lubricating oil is supplied to the second lubricating unit that does not require lubrication in the stopped state. Can be blocked.

  [3] In the present invention, the transmission performs idle neutral control that weakens the engaging force of the starting clutch under a predetermined condition, and the first lubricating portion can include at least the starting clutch.

  According to the present invention, during the idle neutral control, the first lubrication part including the starting clutch is lubricated, but the second lubrication part that does not require lubrication is not lubricated. In addition, energy loss of a pump or the like due to the supply of useless lubricating oil can be prevented, and fuel consumption can be improved.

Explanatory drawing which shows typically embodiment of the lubrication circuit of the transmission of this invention. (A) is a graph which shows the relationship between the oil_pressure | hydraulic of the lubricating oil of this embodiment, and supply_amount | feed_rate. (B) is a graph which shows the relationship between the oil_pressure | hydraulic of lubricating oil and the supply amount in the lubrication circuit of the conventional transmission.

  An embodiment of a lubrication circuit for a transmission according to the present invention will be described with reference to the drawings. FIG. 1 schematically shows a part of a lubricating circuit 1 of a transmission according to the present embodiment. The lubricating circuit 1 includes a base oil passage 3 through which lubricating oil supplied from a hydraulic control unit including a pump 21 and a pressure regulating valve 22 flows, a first oil passage 4 communicating with the base oil passage 3, and a base oil. A branch path 5 that branches from the path 3 in the height direction, and a second oil path 6 and a third oil path 7 that communicate with the upper end of the branch path 5 are provided.

  The pump 21 is operated by a drive source such as an internal combustion engine of the vehicle and discharges lubricating oil to the base oil passage 3. The pressure regulating valve 22 is interposed in the base oil passage 3 and adjusts the hydraulic pressure of the lubricating oil discharged from the pump 21. The pump 21 may be an electric type.

  The pressure regulating valve 22 regulates the lubricating oil supplied from the pump 21 and supplies it to the base oil passage 3.

  The transmission according to the present embodiment improves fuel efficiency by reducing the engagement force of the starting clutch and bringing it closer to the neutral state under predetermined conditions (that is, when the shift range is the traveling range and the vehicle is stopped). Control, so-called idle neutral control is executed.

  Further, the transmission according to the present embodiment includes a start clutch that requires lubrication when the vehicle is stopped and the vehicle is in a start state in which the vehicle is shifted from a state in which idle neutral control is being executed. A first lubrication part 81 such as a clutch, a reverse clutch, a first-speed gear train, etc., a second lubrication part 82 such as a second-speed clutch or a gear train, and a third lubrication part such as a second-speed gear train or a clutch. 83.

  The second lubrication part 82 or the third lubrication part 83 may include a bearing that supports the input / output shaft and the like. When the transmission is a belt-type continuously variable transmission, a contact portion between the belt and the pulley may be included as the second lubrication portion 82 or the third lubrication portion 83. When the transmission is a toroidal continuously variable transmission, the second lubrication part 82 or the third lubrication part 83 may include a contact part between the power roller and the input / output disk.

  Lubricating oil is guided to the first lubricating portion 81 by the first oil passage 4. Lubricating oil is guided to the second lubricating portion 82 by the second oil passage 6. Lubricating oil is guided to the third lubricating portion 83 by the third oil passage 7. The second oil passage 6 is provided with an orifice 6 a for reducing the hydraulic pressure of the lubricating oil flowing through the second oil passage 6. The third oil passage 7 is provided with a choke 7a for reducing the hydraulic pressure of the lubricating oil flowing through the third oil passage 7. An orifice may be used instead of the choke 7a, and a choke may be used instead of the orifice 6a.

  When the hydraulic pressure of the lubricating oil supplied from the pump 21 and the pressure regulating valve 22 of the hydraulic pressure control unit is less than a predetermined pressure P (see FIG. 2A), the branch path 5 has a height that is the same as that of the first oil path 4. Thus, the lubricating oil is supplied to the first lubricating unit 81, the lubricating oil is not supplied to the second lubricating unit 82, and the hydraulic pressure of the lubricating oil supplied from the pump 21 and the pressure regulating valve 22 of the hydraulic control unit is a predetermined pressure. When P is greater than or equal to P (see FIG. 2A), the height is set such that the lubricating oil is supplied to the second lubricating portion 82 via the branch path 5 and the second oil path 6.

For example, if the branch path 5 is a cylinder having a diameter of 10 mm and a height of 50 mm, the specific gravity of the lubricating oil is 0.83 g / cm ^3, and the diameter of the hole communicating with the branch path 5 and the base oil path 3 is defined as 4 mm. The volume of the branch path 5 is 3.93 cm ³ . The maximum weight of the lubricating oil in the branch path 5 is 3.259 g, and the area of the hole where the branch path 5 and the base oil path 3 communicate with each other is 0.126 cm ² . The hydraulic pressure received in the hole through which the branch path 5 and the base oil path 3 communicate is 0.259 kgf / cm ² (25.4 Kpa). Therefore, in the case of this example, until the oil pressure of the lubricating oil flowing through the base oil passage 3 reaches 25.4 Kpa (predetermined pressure P in this case), the second lubricating portion 82 and the third lubricating portion 83 are lubricated. Will not be supplied.

  The first lubrication part 81 is a part that requires lubrication when the vehicle is in a start state in which the vehicle shifts from the stop state to the start state, and includes the start clutch (first speed clutch) as described above. The second lubrication part 82 and the third lubrication part 83 are parts that require lubrication in a running state other than the starting state.

  FIG. 2A is a graph showing a relationship between the hydraulic pressure of the lubricating oil and the supply amount of the lubricating oil according to the present embodiment. FIG. 2B is a graph showing the relationship between the oil pressure of the lubricating oil and the supply amount of the lubricating oil in the conventional lubricating circuit.

  The solid line in FIG. 2 indicates the supply amount of the lubricating oil flowing through the base oil passage 3 with respect to the hydraulic pressure (that is, the total of all the lubricating oils flowing through the first to third oil passages 4, 6, and 7). A dotted line in FIG. 2 indicates a supply amount of the lubricating oil supplied to the first lubricating portion 81 via the first oil passage 4 with respect to the hydraulic pressure. 2 indicates the supply amount of the lubricating oil supplied to the second lubricating portion 82 via the second oil passage 6 with respect to the hydraulic pressure. A two-dot chain line in FIG. 2 indicates a supply amount of the lubricating oil supplied to the third lubricating portion 83 via the third oil passage 7 with respect to the hydraulic pressure.

  According to the lubricating circuit 1 of the transmission of this embodiment, when the hydraulic pressure of the lubricating oil that is regulated by the pressure regulating valve 22 and flows through the base oil passage 3 is less than a predetermined pressure P (see FIG. 2A), The first lubricating part 81 is lubricated, but the supply of the lubricating oil to the second lubricating part 82 is blocked by the action of the branch path 5.

  Therefore, by setting the first lubrication part 81 to a part that requires lubrication and the second lubrication part 82 to a part that does not require lubrication, the idle neutral control is performed as in the conventional case shown in FIG. In addition, in order to ensure the supply amount C (see FIG. 2) of the lubricating oil necessary for the first lubricating portion 81, a large amount of lubricating oil is supplied to the second lubricating portion 82 and the third lubricating portion 83 that do not require lubrication. Can be prevented.

  Thereby, useless energy consumption can be suppressed and the fuel consumption of the vehicle can be improved. In addition, since the supply of the lubricating oil to the second lubrication unit 82 and the third lubrication unit 83 can be prevented without adding a variable resistance unit such as a solenoid valve, an increase in the cost of the lubrication circuit 1 can be suppressed.

  When the vehicle is in a stopped state, the oil pressure of the lubricating oil supplied to the base oil passage 3 is set to be less than a predetermined pressure P by the pump 21 and the pressure regulating valve 22 constituting the hydraulic pressure control unit, thereby stopping the vehicle. In this state, it is possible to prevent the lubricating oil from being supplied to the second lubricating portion 82 that does not require lubrication.

  Further, during the idle neutral control, the first lubrication part 81 including the starting clutch is lubricated, but the second lubrication part 82 that does not require lubrication is not lubricated. For this reason, the lubrication state of the transmission can be maintained appropriately, energy loss associated with the supply of useless lubricating oil can be prevented, and fuel consumption can be improved.

DESCRIPTION OF SYMBOLS 1 ... Lubrication circuit, 21 ... Pump, 22 ... Pressure regulating valve, 3 ... Base oil passage, 4 ... First oil passage, 5 ... Branch passage, 6 ... Second oil passage, 6a ... Orifice, 7 ... Third oil passage , 7a, choke, 81, first lubricating portion, 82, second lubricating portion, 83, third lubricating portion, P, predetermined pressure, and C, supply amount of lubricating oil necessary for the first lubricating portion.

Claims (3)

A base oil passage through which lubricating oil supplied from the hydraulic control unit flows;
A first oil passage that communicates with the base oil passage and guides the lubricating oil to the first lubricating portion;
A branch path that branches in a height direction from the base oil path;
A second oil path that communicates with the upper end of the branch path and guides the lubricating oil to the second lubrication section;
The height of the branch path is
When the hydraulic pressure of the lubricating oil supplied from the hydraulic control unit is less than a predetermined pressure, the lubricating oil is supplied to the first lubricating unit via the first oil passage, and the lubricating oil is supplied to the second lubricating unit. Not supplied,
When the hydraulic pressure of the lubricating oil supplied from the hydraulic control unit is equal to or higher than a predetermined pressure, the height is set such that the lubricating oil is also supplied to the second lubricating unit via the branch path and the second oil path. A lubricating circuit for a transmission. A transmission lubrication circuit according to claim 1,
The hydraulic control unit has a pump that is operated by a drive source of a vehicle,
The first lubrication portion is a portion where lubrication is required when the vehicle is in a start state where the vehicle starts from a stop state.
The lubrication circuit for a transmission, wherein the second lubrication portion is a portion that requires lubrication in a traveling state other than the starting state. A lubrication circuit for a transmission according to claim 2,
The transmission performs idle neutral control to weaken the engagement force of the starting clutch under predetermined conditions.
The transmission lubrication circuit, wherein the first lubrication part includes at least the starting clutch.

Images