A kind of heat dissipating method of friction surface of wet clutch of automobile gear box
Technical field
The invention belongs to the automobile gearbox technical field, relate to the method for a kind of wet clutch heat radiation of rubbing surface when closed.
Background technique
Wet clutch is a kind of device that transmits and cut off moment of torsion that extensively adopts in the automobile gearbox, is made up of the steel driving disc of motor one side and the driven disc of output shaft of gear-box one side, and driven disc has friction lining face.In starting on the vehicle slope, keep on the slope and introduce under the working condition such as sliding that rubs in order to improve property of automatic shft; Cause excessive temperature rise because of the sliding heat that produces that rubs relatively between driving disc and the driven disc; To make friction material aging in advance again; Cold oil decomposes, and finally causes the inefficacy of cooling effect decline and clutch.Therefore, the cooling of clutch friction face is all most important to its performance and long durability.
The cooling of friction surface of wet clutch mainly is to flow through rubbing surface through gear box oil heat is taken away.Yet clutch was in closed state when maximum heat produced, and oil stream is difficult to pass through, and only can from the porous structure of friction material, permeate, and can't satisfy the heat exchange requirement.Therefore, generally all be designed with oil guide slot on the clutch driven plate friction material, make cold oil flow through friction surface smoothly, heat is taken away.The design quality of oil groove is very big to the cooling effect influence, the modal radial alignment shape (see figure 1) that is.Because wet clutch continues temperature between the rubbing surface under the sliding contact condition, to thermal equilibrium, its speed depends on the balance between the heat that cold oil is taken out of in fricative heat and the oil groove from the beginning contact friction.So above-mentioned common oil groove design, temperature gradient is along with oil groove radius (internal diameter is to external diameter) increases, so maximum temperature; Usually occur in the external diameter of rubbing surface; Limited the thermal capacity of clutch and the transmission of moment of torsion, influenced the clutch durability greatly, reliability and efficient.
Summary of the invention
The objective of the invention is: a kind of heat dissipating method of friction surface of wet clutch of automobile gear box is provided,, improves durability, reliability and the efficient of clutch to increase the clutch heat dissipation potential.
For achieving the above object; The technological scheme that adopts is: a kind of heat dissipating method of friction surface of wet clutch of automobile gear box; It is characterized in that: cold oil flows into through the oily outflow opening outflow of cooling oil groove to the driven disc internal diameter from the oily inflow entrance of driven disc external diameter, and cold oil rock and roll in said cooling oil groove flows and fully mixes heat radiation; Said cooling oil groove is for radially being composed in series the said radial direction that radially is meant driven disc by high right low, the left low right high indenting grid-like oil groove of arranging that replaces in a plurality of degree of depth left side.
Said grid-like oil groove be shaped as a kind of in square, rectangular, parallelogram, the trapezoidal and arbitrary quadrilateral, sideline, said grid-like oil groove flow direction both sides is straight line or curve.
The sideline that adjacent grid-like oil groove is vertical with the oil flow direction, the scope of being overlapping are 5%~95%.
High right low, the left low right height in a described grid-like oil groove degree of depth left side is that the center line that flows to cold oil is a benchmark, and is dark away from a side of center line, shallow near a side of center line.
Said cold oil flows into through the oily outflow opening outflow of cooling oil groove to internal diameter from the oily inflow entrance of external diameter, can follow any angle and path.
The invention has the beneficial effects as follows: in adjacent two short lines oil grooves connect the shear layer of oil stream in step downstream of reducing place, produce strong local turbulence, strengthened momentum and energy interchange in the oily stream, thereby improved heat transfer; The reverse slip of driving disc and driven disc causes the circulation vertical with the oil groove flow direction on the rubbing surface, and the oil of lower temperature is constantly rolled to the frictional interface place, has increased heat transfer temperature difference, thereby has improved heat transfer; The variation of high right low, the left low right high alternately arrangement in the left side of oil duct and the degree of depth makes oily stream rock and roll, has strengthened the pulsation of main flow, thereby has improved the mixing between the cold and hot oil, and then improved the durability of clutch, reliability and efficient.
Description of drawings
Following Figure of description and embodiment are described further the present invention.
Fig. 1 moves towards schematic representation for existing technology cooling tank structure;
Fig. 2 moves towards schematic representation for the present invention cools off tank structure;
Fig. 3 is A-A section (left side the is low right high) structural representation of Fig. 2;
Fig. 4 is B-B section (left side the is high right low) structural representation of Fig. 2.
Among the figure: the 1-friction material; 2-cools off oil groove; 3-oil inflow entrance: 4-oil outflow opening; The grid-like oil groove of 5-.
Embodiment
Fig. 1~cooling oil groove shown in Figure 4 is taken from a section in the Automatic Transmission's lock-up Clutch annular friction sheet.Fig. 1 moves towards schematic representation for existing technology cooling tank structure, and cooling oil groove 2 is a radial alignment shape, and maximum temperature usually occurs in the external diameter of rubbing surface, and radiating effect is bad.
Fig. 2~Fig. 4 shows schematic representation for the section shape that the present invention cools off tank structure trend and grid-like oil groove.Visible by figure; A kind of heat dissipating method of friction surface of wet clutch of automobile gear box; It is characterized in that: cold oil flows into through oily outflow opening 4 outflows of cooling oil groove 2 to the driven disc internal diameter from the oily inflow entrance 3 of driven disc external diameter, and cold oil rock and roll in said cooling oil groove 2 flows and fully mixes heat radiation; Said cooling oil groove 2 is for radially being composed in series the said radial direction that radially is meant driven disc by high right low, the left low right high indenting grid-like oil groove of arranging 5 that replaces in a plurality of left sides.
Said grid-like oil groove 5 be shaped as a kind of in square, rectangular, parallelogram, the trapezoidal and arbitrary quadrilateral, sideline, grid-like oil groove 5 oil flow direction both sides is straight line or curve.The sideline scope of being overlapping that adjacent grid-like oil groove 5 is vertical with the oil flow direction is 5%~95%.
High right low, the left low right height in described grid-like oil groove 5 degree of depth left side is that the center line that flows to cold oil is a benchmark, and is dark away from a side of center line, shallow near a side of center line.
Said cold oil flows into through oily outflow opening 4 outflows of cooling oil groove 2 to internal diameter from the oily inflow entrance 3 of external diameter, can follow any angle and path.Its angle (like α, β angle among Fig. 2) that flows to center line and driven disc circle edge can be to less than any value between 180 ° greater than 0 °.
Cooling oil groove " rock and roll+radially square shape " pattern comprises a plurality of oil groove friction fields increasing high Turbulent Kinetic and to increase the pulsation of the main flow between the radial groove, to realize flow equilibrium and to reduce cavity flow and because centrifugal force produces the emptying phenomenon; The reverse slip of driving disc and driven disc causes the circulation vertical with the oil groove flow direction on the rubbing surface; The oil of lower temperature is constantly rolled to the frictional interface place; Increased heat transfer temperature difference; Thereby improved heat transfer, more reasonably a frictional surface temperature distribution and an increase clutch heat dissipation potential are provided.
Cooling oil groove according to the invention is applicable to the wet clutch that has slippage on lock-up clutch, the main clutch in the automatic mechanical transmission, double clutch or other any rubbing surface in the automatic transmission.