JP2021001669A - sprocket - Google Patents

Abstract

To allow for efficient lubrication.SOLUTION: A sprocket 31 includes a tooth part 312 engaging with a chain 21. The tooth part 312 includes: a catch groove 312a receiving fed oil; and an oil groove 312b connected to the catch groove 312a. The catch groove 312a is formed deeper than the oil groove 312b in an oil-groove. The oil groove 312b reaches a contact surface 312c of the tooth part 312 to the chain 21 from the catch groove 312a.SELECTED DRAWING: Figure 5

Description

The present invention relates to sprockets.

Patent Document 1 discloses a transfer device provided with an oil injection nozzle for injecting lubricating oil between a sprocket and a chain.

Jikkenhei 4-5553

When oil is injected into the meshing start portion between the sprocket and the chain for forced lubrication, the oil is sprayed from the front of the meshing start portion. Therefore, there is a possibility that the lubrication efficiency may be lowered to some extent due to oil or the like that does not properly reach the meshing start portion. As a result, by supplying more oil than required, the work load of the oil pump may increase and energy efficiency may deteriorate.

The present invention has been made in view of such a problem, and an object of the present invention is to enable efficient lubrication.

A sprocket according to an aspect of the present invention is a sprocket having a tooth portion that meshes with a chain, and the tooth portion has a catch groove that receives supplied oil and an oil groove that connects to the catch groove. The catch groove is formed deeper in the axial direction than the oil groove. Further, the oil groove reaches the meshing surface of the tooth portion with the chain from the catch groove.

According to this aspect, the oil supplied to the catch groove reaches the meshing surface with the chain through the oil groove by centrifugal force. Therefore, the meshing portion between the chain and the sprocket is directly lubricated, so that the lubrication efficiency is improved and the amount of oil supplied can be reduced, so that efficient lubrication is possible.

It is a schematic block diagram of a hybrid vehicle. It is a front view of a sprocket. It is sectional drawing of a sprocket. It is a figure which shows the state in which the sprocket is assembled in the cross section. It is an enlarged view of the main part of the vertical cross section of a tooth part. It is an enlarged view of the main part of the cross section of a tooth part. It is a figure which shows the main part of the 1st modification in a vertical cross section. It is a figure which shows the main part of the 1st modification in the cross section. It is a figure which shows the main part of the 2nd modification in the vertical cross section. It is a figure which shows the main part of the 2nd modification in the cross section.

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

FIG. 1 is a schematic configuration diagram of a hybrid vehicle 100 (hereinafter, referred to as “vehicle 100”) according to an embodiment of the present invention. The vehicle 100 includes a low-voltage battery 1 as a first battery, a high-voltage battery 2 as a second battery, an engine 3 as a driving drive source, a motor generator 4 (hereinafter referred to as "MG4"), and an engine. The starter motor 5 (hereinafter referred to as "SM5") as the first rotary electric machine used for starting the engine 3 and the starter generator 6 (hereinafter referred to as "SM5") as the second rotary electric machine used for power generation, assisting and starting the engine 3. (Referred to as "SG6"), a DC-DC converter 7, an inverter 8, a mechanical oil pump 9 and an electric oil pump 10 as hydraulic sources, a torque converter 11 constituting a transmission, a forward / backward switching mechanism 12, and a forward / backward switching mechanism 12. It includes a stepless speed change mechanism 13 (hereinafter, referred to as “CVT 13”), a differential mechanism 14, a drive wheel 18, and a controller 20.

The low voltage battery 1 is a lead acid battery having an output voltage of DC12V. The low-voltage battery 1 is connected to the low-voltage circuit 16 together with electrical components 15 (automatic driving camera 15a and sensor 15b, navigation system 15c, audio 15d, air conditioner blower 15e, etc.) that operate at SM5 and 12V. The low voltage battery 1 may be a lithium ion battery having an output voltage of 12 V.

The high-voltage battery 2 is a DC48V lithium-ion battery having a higher output voltage than the low-voltage battery 1. The output voltage of the high voltage battery 2 may be lower or higher than this, for example, 30V or 100V. The high-voltage battery 2 is connected to the high-voltage circuit 17 together with the MG4, SG6, inverter 8, electric oil pump 10, and the like.

The low-voltage circuit 16 and the high-voltage circuit 17 are connected via a DC-DC converter 7. The DC-DC converter 7 has a boosting function that boosts 12V of the low voltage circuit 16 to 48V and outputs 48V to the high voltage circuit 17, and steps down 48V of the high voltage circuit 17 to 12V to supply 12V to the low voltage circuit 16. It has a step-down function to output. As a result, the DC-DC converter 7 can output a voltage of 12 V to the low voltage circuit 16 regardless of whether the engine 3 is running or stopped. When the remaining capacity of the high-voltage battery 2 is low, the 12V of the low-voltage circuit 16 can be boosted to 48V and output to the high-voltage circuit 17 to charge the high-voltage battery 2.

The engine 3 is an internal combustion engine that uses gasoline, light oil, or the like as fuel, and its rotational speed, torque, or the like is controlled based on a command from the controller 20.

The torque converter 11 is provided on the power transmission path between the engine 3 and the forward / backward switching mechanism 12, and transmits power via a fluid. Further, the torque converter 11 can improve the power transmission efficiency of the driving force from the engine 3 by engaging the lockup clutch 11a when the vehicle 100 is traveling at a predetermined lockup vehicle speed or higher.

The forward / backward switching mechanism 12 is provided on the power transmission path between the torque converter 11 and the CVT 13, and includes a planetary gear mechanism 12a, a forward clutch 12b, and a reverse brake 12c. When the forward clutch 12b is engaged and the reverse brake 12c is released, the rotation of the engine 3 input to the forward / backward switching mechanism 12 via the torque converter 11 is transferred from the forward / backward switching mechanism 12 to the CVT 13 while maintaining the rotation direction. It is output. On the contrary, when the forward clutch 12b is released and the reverse brake 12c is engaged, the rotation of the engine 3 input to the forward / backward switching mechanism 12 via the torque converter 11 is decelerated and the rotation direction is reversed to switch forward / backward. It is output from the mechanism 12 to the CVT 13. The flood control required by the forward / backward switching mechanism 12 is generated by a hydraulic circuit (not shown) using the flood pressure generated by the mechanical oil pump 9 or the electric oil pump 10 as the original pressure.

The CVT 13 is arranged on the power transmission path between the forward / backward switching mechanism 12 and the differential mechanism 14, and changes the gear ratio steplessly according to the vehicle speed, the accelerator opening degree which is the operation amount of the accelerator pedal, and the like. The CVT 13 includes a primary pulley 13a, a secondary pulley 13b, and a belt 13c wound around both pulleys. In the CVT 13, the gear ratio can be changed steplessly by changing the groove widths of the primary pulley 13a and the secondary pulley 13b by flood control and changing the contact radius between the pulleys 13a and 13b and the belt 13c. The flood pressure required by the CVT 13 is generated by a hydraulic circuit (not shown) using the flood pressure generated by the mechanical oil pump 9 or the electric oil pump 10 as the original pressure.

The MG4 is a synchronous rotary electric machine in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator. The MG4 is connected to the shaft of the primary pulley 13a via a chain 21 wound between the sprocket provided on the shaft of the MG4 and the sprocket provided on the shaft of the primary pulley 13a.

The MG 4 is branched and connected to the power transmission path connecting the engine 3 and the drive wheels 18 on the engine 3 side of the secondary pulley 13b. Further, the MG 4 is branched and connected to the power transmission path on the drive wheel 18 side of the forward / backward switching mechanism 12 including the clutch provided between the engine 3 and the primary pulley 13a of the power transmission path. Connecting the belt 13c to the shaft of the primary pulley 13a from the side opposite to the engine 3 with the belt 13c in between is included in the branch connection to the power transmission path.

The MG 4 is controlled by applying a three-phase alternating current generated by the inverter 8 based on a command from the controller 20. The MG 4 operates as an electric motor that is rotationally driven by receiving electric power supplied from the high-voltage battery 2. Further, the MG 4 functions as a generator that generates an electromotive force at both ends of the stator coil when the rotor receives rotational energy from the engine 3 and the drive wheels 18, and can charge the high voltage battery 2.

The sprocket provided on the shaft of the MG4 and the sprocket provided on the shaft of the primary pulley 13a are configured so that the latter has a large number of teeth (for example, the number of teeth = 1: 3), and the output rotation of the MG3 is decelerated. Is transmitted to the primary pulley 13a. As a result, the torque required for the MG4 is reduced, the MG4 is miniaturized, and the degree of freedom in arranging the MG4 is improved.

The SM5 is a DC motor, and is arranged so that the pinion gear 5a can be meshed with the outer peripheral gear 3b of the flywheel 3a of the engine 3. When the engine 3 is started from a cold state for the first time (hereinafter referred to as "first start"), power is supplied from the low voltage battery 1 to the SM5, the pinion gear 5a is meshed with the outer gear 3b, the flywheel 3a, and further. The crankshaft is rotated. Since the low-voltage battery 1 is a lead-acid battery, the SM5 is used when the engine 3 is started for the first time, so that power can be stably supplied from the low-voltage battery 1 to the SM5 even at extremely low temperatures. This is because the SM5 can generate the torque and output required to start the engine 3 for the first time.

The torque and output required to start the engine 3 are the largest at the first start, and are smaller at the start from the warm-up state, that is, at the restart than at the first start. This is because the temperature of the engine oil is low and the viscosity of the engine oil is high at the first start, whereas the temperature of the engine oil rises and the viscosity of the engine oil decreases after the first start.

The SG6 is a synchronous rotary electric machine, which is connected to the crankshaft of the engine 3 via a V-belt 22 and functions as a generator when receiving rotational energy from the engine 3. The electric power generated in this way is charged into the high voltage battery 2 through the inverter 8. Further, the SG 6 operates as an electric motor that is rotationally driven by receiving electric power supplied from the high-voltage battery 2, and assists the driving force of the engine 3. Further, the SG6 is used to rotationally drive the crankshaft of the engine 3 to restart the engine 3 when the engine 3 is restarted from the idling stop state.

The mechanical oil pump 9 is an oil pump that operates by transmitting the rotation of the engine 3 via the chain 23. The mechanical oil pump 9 sucks up the hydraulic oil stored in the oil pan and supplies the oil to the lockup clutch 11a, the forward / backward switching mechanism 12 and the CVT 13 via a hydraulic circuit (not shown).

The electric oil pump 10 is an oil pump operated by electric power supplied from the high voltage battery 2. The electric oil pump 10 operates when the engine 3 is stopped and the mechanical oil pump 9 cannot be driven by the engine 3, such as in EV mode or idle stop state, and is stored in the oil pan in the same manner as the mechanical oil pump 9. The oil is sucked up and supplied to the lockup clutch 11a, the forward / backward switching mechanism 12 and the CVT 13 via a hydraulic circuit (not shown). In particular, by securing the necessary flood pressure in the CVT 13, the slip of the belt 13c is suppressed.

The controller 20 is composed of one or a plurality of microcomputers including a central arithmetic unit (CPU), a read-only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). The controller 20 corresponds to the control unit, and by executing the program stored in the ROM or RAM by the CPU, the engine 3, the inverter 8 (MG4, SG6, the electric oil pump 10), the DC-DC converter 7, the SM5, The lockup clutch 11a, the forward / backward switching mechanism 12, the CVT 13, and the like are controlled in an integrated manner.

As the operation mode of the vehicle 100, the controller 20 drives the MG4 with the electric power supplied from the high-voltage battery 2 and travels by the driving force of the MG4 only, and the engine traveling mode of traveling by the driving force of the engine 3 only. And the HEV mode in which the vehicle travels according to the driving force of the engine 3 and the driving force of the MG 4.

In the EV mode, the vehicle 100 travels by driving only the MG4 with the electric power from the high-voltage battery 2 in a state where the forward clutch 12b and the reverse brake 12c are released (hereinafter, this state is referred to as "EV travel"). .. The EV mode is selected when the required output of the vehicle 100 is low and the remaining capacity of the high voltage battery 2 is sufficient.

In the engine running mode, the vehicle 100 runs by driving only the engine 3 with either the forward clutch 12b or the reverse brake 12c engaged. The engine running mode is selected when the required output of the vehicle 100 is relatively high.

In the HEV mode, the vehicle 100 runs by driving the engine 3 and the MG 4 with either the forward clutch 12b or the reverse brake 12c engaged. The HEV mode is selected when the required output of the vehicle 100 is high, specifically, when the required output of the vehicle 100 cannot be supplemented only by the output of the engine 3.

The controller 20 selects a driving mode based on the accelerator opening, the pedal effort of the brake pedal, and the vehicle speed in consideration of a driving mode selection map (not shown), and sets the engines 3 and MG 4 so that the selected driving mode is realized. Drive.

FIG. 2 is a front view of the sprocket 31. FIG. 3 is a cross-sectional view of the sprocket 31. FIG. 4 is a cross-sectional view showing a state in which the sprocket 31 is assembled.

The sprocket 31 constitutes a sprocket provided on the shaft of the primary pulley 13a, and has a disk portion 311 and a tooth portion 312 and a shaft portion 313. The disk portion 311 constitutes the main body portion of the sprocket 31. The disk portion 311 is provided with a tooth portion 312 and a shaft portion 313.

The tooth portion 312 is a ring-shaped portion on which sprocket teeth are formed, and is provided on the outer peripheral portion of the disk portion 311. The tooth portion 312 is provided so as to be offset in the axial direction from the disk portion 311. The tooth portion 312 is provided offset to the side where the shaft portion 313 is provided. The shaft portion 313 is provided so as to project from the central portion of the disk portion 311.

The sprocket 31 is assembled to the shaft of the primary pulley 13a, and the chain 21 is hung around the sprocket 31. The shaft of the primary pulley 13a is supported by a bearing 41, which is provided in the case 42. The case 42 is a case of CVT 13, and the case 42 is provided with a supply oil passage 43.

The supply oil passage 43 supplies oil to the inside of the tooth portion 312 in the radial direction. The supply oil passage 43 is provided so as to supply oil in the axial direction, and is provided so as to receive the oil supplied in the axial direction in the catch groove 312a described later. The tooth portion 312 is provided with a groove as described below.

FIG. 5 is an enlarged view of a main part of the vertical cross section of the tooth portion 312. FIG. 6 is an enlarged view of a main part of the cross section of the tooth portion 312. The tooth portion 312 is provided with a catch groove 312a and an oil groove 312b. The catch groove 312a receives the oil supplied from the axial direction by the supply oil passage 43. The catch groove 312a is provided in the radial inner portion of the tooth portion 312. The catch groove 312a has a groove shape that opens in the radial direction and one end side in the axial direction (the side opposite to the disk portion 311 side in the axial direction). The catch groove 312a is formed deeper in the axial direction than the oil groove 312b. The catch groove 312a is provided on the tooth portion 312 over the entire circumference.

The oil groove 312b is provided on one end side of the tooth portion 312 in the axial direction and is connected to the catch groove 312a. The oil groove 312b has a groove shape that is open on one end side in the axial direction. The oil groove 312b reaches the contact surface 312c of the meshing surface with the chain 21 (tooth surface of the tooth portion 312) from the catch groove 312a with the chain 21. The oil groove 312b extends radially outward from the catch groove 312a, further branches toward each of the two contact surfaces 312c on the forward rotation side and the reverse rotation side, and reaches these two contact surfaces 312c. The oil grooves 312b are provided in each of the plurality of teeth of the sprocket teeth.

Next, the main effects of the present embodiment will be described.

The sprocket 31 has a tooth portion 312 that meshes with the chain 21. The tooth portion 312 has a catch groove 312a that receives the supplied oil and an oil groove 312b that connects to the catch groove 312a. The catch groove 312a is formed deeper in the axial direction than the oil groove 312b. The oil groove 312b reaches the contact surface 312c of the tooth portion 312 with the chain 21 from the catch groove 312a.

According to such a configuration, the oil supplied to the catch groove 312a reaches the contact surface 312c with the chain 21 via the oil groove 312b by centrifugal force. Therefore, since the meshing portion between the chain 21 and the sprocket 31 is directly lubricated, the lubrication efficiency is improved and the amount of oil supplied can be reduced, so that efficient lubrication is possible. Further, according to such a configuration, the contact portion with the chain 21 can be directly lubricated, so that the lubrication efficiency is high (effect corresponding to claim 1).

The sprocket 31 has a disk portion 311 provided with a tooth portion 312. The tooth portion 312 is provided so as to be offset in the axial direction from the disk portion 311.

According to such a configuration, the catch groove 312a and the oil groove 312b can be appropriately provided. Further, even in the supply oil passage 43 provided in the case 43 for supplying oil in the axial direction, the oil can be appropriately supplied to the catch groove 312a, and it is not necessary to supply the oil by another member such as a tube. .. Therefore, according to such a configuration, a rational configuration can be obtained in order to enable efficient lubrication (effect corresponding to claim 2).

The oil groove 312b may be provided as described below.

7 and 8 are views showing a first modification. 9 and 10 are views showing a second modification. As shown in FIGS. 7 and 8, the oil groove 312b may be provided so as to reach the tooth tip surface 312d of the meshing surface with the chain 21 from the catch groove 312a. Further, as shown in FIGS. 9 and 10, the oil groove 312b may be provided so as to reach the tooth bottom surface 312e of the meshing surface with the chain 21 from the catch groove 312a.

Even in these cases, the lubrication efficiency can be improved by directly lubricating the meshing portion between the chain 21 and the sprocket 31. Therefore, the amount of oil supplied can be reduced, and efficient lubrication becomes possible (effect corresponding to claim 1).

Although the embodiments of the present invention have been described above, the above embodiments are only a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configurations of the above embodiments. Absent.

21: Chain 31: Sprocket 311: Disc portion 312: Tooth portion 312a: Catch groove 312b: Oil groove 312c: Contact surface (meshing surface)
312d: Tooth tip surface (meshing surface)
312e: Tooth bottom surface (meshing surface)

Claims (2)

A sprocket with teeth that mesh with the chain
The tooth portion has a catch groove for receiving the supplied oil and an oil groove connected to the catch groove.
The catch groove is formed deeper in the axial direction than the oil groove.
The oil groove reaches the meshing surface of the tooth portion with the chain from the catch groove.
A sprocket that features that. The sprocket according to claim 1.
It has a disk portion on which the tooth portion is provided, and has a disk portion.
The tooth portion is provided so as to be offset in the axial direction from the disk portion.
A sprocket that features that.

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