CN218326198U - Low-friction crankshaft oil seal for commercial vehicle engine - Google Patents

Abstract

The utility model discloses a low friction crankshaft oil seal of a commercial vehicle engine, which relates to the technical field of automobile accessories, and comprises an outer oil seal assembly, an inner oil seal assembly and a PTFE gasket; the inner oil seal assembly comprises an inner oil seal framework and an inner oil seal rubber body; the outer oil seal assembly comprises an outer oil seal framework and an outer oil seal rubber body; the PTFE washer comprises a body, a first power lip and a second power lip, and the body is connected with the inclined section of the outer oil seal assembly; one end of the first power lip is connected with the body, and the other end of the first power lip abuts against the bottom surface of the first horizontal section of the inner oil seal assembly to form axial self-sealing; one end of the second power lip is connected with the body, and the other end of the second power lip abuts against the inner wall of the first vertical section of the inner oil seal assembly to form radial self-sealing.

Description

Low-friction crankshaft oil seal for commercial vehicle engine

Technical Field

The utility model relates to an auto-parts technical field, specifically a commercial car engine low friction bent axle oil blanket.

Background

Along with the development of new technologies, the stricter energy crisis and environmental protection in recent years, the rubber and plastic sealing element has stricter working conditions, higher requirements on sealing materials and structures are provided, the high and low temperature resistance range is wider, the low friction and self-lubricating performance and corrosion resistance are better, the starting torque is smaller, and the sealing performance is more reliable.

The special high-performance engineering elastomer FKM has become one of the main materials for meeting the application of a high-performance sealing element, and the sealing for a rotating shaft generally adopts a fluid dynamic rubber lip-shaped sealing ring structure, and a permanent radial force is provided by an oil seal spring.

Low friction, self-lubricating fluoroplastics (particularly PTFE) are key materials for achieving oil-free seals, as well as high vacuum seals, constant friction seals for fluid transmission systems, and hydraulic seal technologies, and PTFE has become widely and mature in application.

On a high-horsepower engine of a medium-heavy vehicle, an oil seal and a shaft are difficult to assemble and are easy to leak oil in the prior art; meanwhile, the surface roughness of the shaft cannot reach the proper surface roughness range Ra0.1.6-Ra0.4 mu m required by sealing due to the limitation of the processing technology, so that the rapid wear of the lip is aggravated, and the service life is shortened.

The high-horsepower engine is mounted on a medium-heavy vehicle, the high-horsepower engine is mostly operated in mines and rural road mines in the use environment, on one hand, the mechanical vibration is large, the oil film of the crankshaft oil seal is easily damaged to cause leakage, on the other hand, the muddy water and dust in the use environment are large, and after mud and sand enter the sealing surface, the lip of the oil seal is worn at early stage, so that the service life of the oil seal is shortened.

In addition, the eccentricity of the seat due to the misalignment of the shaft with the hole, due to machining and assembly errors; the radial run-out caused by bending, dislocation or unbalance of the rotating shaft, the fatigue damage caused by abrasion and incremental hardening of the elastomer can be gradually increased by the overlarge eccentricity of the shaft and the seat, the sealing performance is influenced, for example, the total run-out is more than 0.7mm, and the common rubber sealing ring cannot meet the use requirement.

When the oil seal works actually, for example, when the oil seal of a crankshaft and a distribution shaft of an automobile engine is started, engine oil flows to a contact surface between the oil seal and the shaft from an oil tank and fills the whole gap for 2-5s, so that the oil seal is started by dry friction, the starting friction force is extremely high, and the wear resistance of the oil seal is tested when the shaft is started and stopped for many times.

That is, when the surface of the shaft is rough to the service conditions required for sealing; when the assembly environment of customer can't reach the requirement, when using under the extremely environment of repugnant industry in mine, rural area, mechanical oscillation aggravation, muddy water, dust are more, under equal oil consumption, the more the effective work that the car made is the better, ordinary structure sealing washer will can't satisfy its operation requirement, also can't satisfy customer's long mileage, non-maintaining requirement. Therefore, it is a strong demand of oil seal factories in recent years to improve the mechanical efficiency of engines and reduce mechanical loss, and to improve the eccentricity resistance, vibration resistance and dust resistance of engine oil seals.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects in the prior art, the utility model aims to provide a low-friction crankshaft oil seal for a commercial vehicle engine, the friction torque between the oil seal and a rotating shaft can be reduced by 30-50%, the mechanical loss is reduced, the effective work output of the engine is increased, and the problem that the oil seal lip is excessively quickly abnormally abraded due to the fact that the shaft surface roughness can not meet the requirement can be solved; the problem that the oil film is damaged and the sealing is invalid due to the eccentricity of the shaft seat, overlarge jump and overlarge mechanical vibration is solved, the dustproof capacity of the oil seal is enhanced, the sealing performance of the oil seal is improved, and the service life of the oil seal is prolonged.

In order to achieve the above purpose, the utility model adopts the technical proposal that: a commercial vehicle engine low-friction crankshaft oil seal comprises an outer oil seal assembly, an inner oil seal assembly and a PTFE gasket; the inner oil seal assembly comprises an inner oil seal framework and an inner oil seal rubber body, wherein the inner oil seal framework comprises a first vertical section, a second vertical section and a first horizontal section which are sequentially connected; the inner oil seal rubber body is arranged on the outer wall of the second vertical section; the outer oil seal assembly comprises an outer oil seal framework and an outer oil seal rubber body, wherein the outer oil seal framework comprises a third vertical section, a fourth vertical section, a second horizontal section and an inclined section which are sequentially connected; the outer oil seal rubber body is arranged on the outer walls of the fourth vertical section, the second horizontal section and the inclined section; the PTFE gasket comprises a body, a first power lip and a second power lip, and the body is connected with the inclined section of the outer oil seal assembly; one end of the first power lip is connected with the body, and the other end of the first power lip abuts against the bottom surface of the first horizontal section of the inner oil seal assembly to form axial self-sealing; one end of the second power lip is connected with the body, and the other end of the second power lip abuts against the inner wall of the first vertical section of the inner oil seal assembly to form radial self-sealing.

The further improvement lies in that: the lower end of the first vertical section is bent inwards to form a first flanging, a first transition inclined plane is arranged at the joint of the upper end of the first vertical section and the lower end of the second vertical section, and a force returning part is arranged between the upper end of the second vertical section and the first horizontal section.

The further improvement lies in that: the inner oil seal rubber body is flush with the outer wall of the first vertical section.

The further improvement lies in that: the outer side wall of the inner oil seal rubber body is provided with a plurality of first convex rings.

The further improvement is that: a guide inclined plane is arranged on the outer side of the upper end of the third vertical section, and a second transition inclined plane is arranged at the joint of the lower end of the third vertical section and the upper end of the fourth vertical section; the lower extreme and the second horizontal segment of slope section are connected, and the upper end of slope section outwards buckles and forms the second turn-ups.

The further improvement lies in that: the part of the outer oil seal rubber body, which is positioned on the fourth vertical section, is flush with the outer wall of the third vertical section; the part of the outer oil seal rubber body, which is positioned at the second horizontal section, is flush with the bottom of the outer oil seal assembly.

The further improvement is that: and a plurality of second convex rings are arranged on the part of the outer oil seal rubber body positioned on the fourth vertical section.

The further improvement lies in that: one side of the body opposite to the outer oil seal assembly is provided with a connecting groove matched with the second flanging, and the top surface of the body is provided with a positioning groove.

The further improvement lies in that: the first power lip is a fluororubber power lip, and a plurality of first thread grooves with arc T-shaped structures are arranged on the first power lip.

The further improvement lies in that: the second power lip is a PTFE power lip, and a plurality of second thread grooves with circular arc R-shaped structures are arranged on the second power lip.

The beneficial effects of the utility model reside in that:

1. in the utility model, the friction torque between the oil seal and the rotating shaft can be reduced by 30-50%, the mechanical loss is reduced, the output of effective work of the engine is increased, and the problem of abnormal abrasion of the oil seal lip caused by the fact that the surface roughness of the shaft can not meet the requirement can be solved; the problem that the oil film is damaged and the sealing is invalid due to the fact that the shaft seat is eccentric, the bounce is overlarge and the mechanical vibration is overlarge is solved, the dustproof capacity of the oil seal is enhanced, the sealing performance of the oil seal is improved, and the service life of the oil seal is prolonged.

2. The utility model discloses after the oil blanket combination, the seal lip not with rotation axis direct contact, reduced the roughness requirement and the hardness requirement of rotation axis to customer department axle, saved customer's manufacturing cost.

3. The oil seal after the novel combination of the utility model has two sealing lips, namely a radial polytetrafluoroethylene power lip and an axial fluororubber power lip, when the dynamic jumping amount of the shaft is large or the mechanical vibration is large, the oil film of the radial PTFE lip is damaged, leakage occurs, the axial rubber power lip can return the leaked oil to the oil pump side, when axial float occurs, the oil film of the axial rubber power lip is damaged, leakage occurs, and the radial PTFE lip can return the leaked oil to the oil tank, thereby achieving the double-insurance effect;

4. in the oil seal newly combined by the utility model, the radial polytetrafluoroethylene power lip thread groove adopts a semicircular R-shaped structure, and the axial rubber power lip thread groove adopts a T-shaped structure with a circular arc, so that the contact area between the oil seal lip and the sealing surface is reduced, the friction torque is integrally reduced by 30-50%, the 'carbon deposit' phenomenon of the lip is reduced, the service life is prolonged, meanwhile, the mechanical loss is reduced, and the mechanical efficiency of the engine is increased;

5. the utility model discloses a to the PTFE power lip of air side upset to guarantee that outside dust, impurity etc. can't get into sealed face, make sealed face cleaner, thereby the effectual life who improves the oil blanket. Meanwhile, the PTFE power lip which is arranged at the middle end of the outer oil seal assembly and overturns towards the air side has the function of preventing external sand and mud, and a non-woven fabric or rubber dustproof opening is not required to be added.

6. The utility model discloses the oil blanket after the new combination has reduced because the oil blanket adorns partially or lip fish tail, the roll-over and leads to the risk of oil leak, has increased the oneself protect function of oil blanket in transportation and assembly.

7. The utility model discloses in, the internal diameter of oil blanket and oil blanket external diameter have all adopted half package structure, by expose skeleton (inside and outside oil blanket skeleton) and the sealed muscle structure of endocyst (inside and outside oil blanket rubber body) constitute and with rotation axis, oil blanket aperture interference fit to guarantee that the oil blanket installation accuracy is high, the heat dissipation is fast, not kick-back and airtight trafficability characteristic is good.

Drawings

FIG. 1 is a schematic structural view of a low-friction crankshaft oil seal of a commercial vehicle engine according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of an inner oil seal assembly, an outer oil seal assembly and a PTFE washer in an embodiment of the present invention;

FIG. 3 is a schematic structural view of an inner oil seal assembly according to an embodiment of the present invention;

FIG. 4 is a schematic structural view of an outer oil seal assembly according to an embodiment of the present invention;

FIG. 5 is a schematic structural view of a PTFE gasket according to an embodiment of the present invention;

FIG. 6 is an enlarged view of portion A of FIG. 5;

FIG. 7 is an enlarged view of portion B of FIG. 5;

fig. 8 is a schematic structural view of a production mold of an inner oil seal assembly in an embodiment of the present invention;

FIG. 9 is a semi-finished product of the inner oil seal assembly made in FIG. 8;

FIG. 10 is a schematic diagram of the mold for producing the outer oil seal assembly and the PTFE washer according to the embodiment of the present invention;

FIG. 11 is a semi-finished outer oil seal assembly and PTFE gasket made in FIG. 10;

fig. 12 is a schematic structural diagram of a tooling for assembling the inner oil seal assembly, the outer oil seal assembly and the PTFE washer according to an embodiment of the present invention.

Reference numerals:

1-an inner oil seal assembly; 11-inner oil seal framework; 111-a first vertical section; 112-a second vertical section; 113-a first horizontal segment; 114-a first cuff; 115-a first transition ramp; 116-a return force portion; 12-inner oil seal rubber body; 121-a first convex ring;

2-an outer oil seal assembly; 21-outer oil seal framework; 211-a third vertical section; 212-a fourth vertical section; 213-a second horizontal segment; 214-an inclined section; 215-a guide ramp; 216-a second transition ramp; 217-second flanging; 22-outer oil seal rubber body; 221-a second convex ring;

3-PTFE gasket; 31-a body; 311-a connecting groove; 312-a positioning groove; 32-first powered lip; 321-a first thread groove; 33-a second powered lip; 331-second thread groove.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout.

In the description of the present invention, it should be noted that, for the terms of orientation, such as "central", "transverse (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like, indicate that the orientation and positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, but not for indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the specific scope of the present invention.

Furthermore, if the terms "first" and "second" are used for descriptive purposes only, they are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. Thus, the definition of "a first" or "a second" feature may explicitly or implicitly include one or more of the features, and as used in the description of the invention, the definition of "a plurality" or "a plurality" means two or more unless otherwise explicitly specified.

In the present invention, unless otherwise expressly specified or limited, the terms "assembled", "connected", and "connected", if any, are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; or may be a mechanical connection; the two elements can be directly connected with each other or connected with each other through an intermediate medium, and the two elements can be communicated with each other. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

In the present application, unless otherwise specified or limited, "above" or "below" a first feature may include the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact with each other through another feature therebetween. Also, the first feature being "above," "below," and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply an elevation which indicates a level of the first feature being higher than an elevation of the second feature. The first feature being "above", "below" and "beneath" the second feature includes the first feature being directly below or obliquely below the second feature, or merely means that the first feature is at a lower level than the second feature.

The technical solution and the advantages of the present invention will be more clear and clear by further describing the embodiments of the present invention with reference to the drawings of the specification. The embodiments described below are exemplary and are intended to be illustrative of the present invention, but should not be construed as limiting the invention.

Referring to fig. 1 and fig. 2, an embodiment of the present invention provides a low friction crankshaft oil seal for a commercial vehicle engine, including an outer oil seal assembly 2 and an inner oil seal assembly 1, and further including a PTFE washer 3;

referring to fig. 3, the inner oil seal assembly 1 includes an inner oil seal framework 11 and an inner oil seal rubber body 12, where the inner oil seal framework 11 includes a first vertical section 111, a second vertical section 112, and a first horizontal section 113 that are connected in sequence; the inner oil-sealed rubber body 12 is arranged on the outer wall of the second vertical section 112; specifically, the lower end of the first vertical section 111 is bent inward to form a first flange 114, a first transition inclined plane 115 is disposed at a joint between the upper end of the first vertical section 111 and the lower end of the second vertical section 112, and a force returning part 116 is disposed between the upper end of the second vertical section 112 and the first horizontal section 113. The inner oil-seal rubber body 12 is flush with the outer wall of the first vertical section 111. The outer side wall of the inner oil seal rubber body 12 is provided with a plurality of first convex rings 121.

Referring to fig. 4, the outer oil seal assembly 2 includes an outer oil seal framework 21 and an outer oil seal rubber body 22, and the outer oil seal framework 21 includes a third vertical section 211, a fourth vertical section 212, a second horizontal section 213 and an inclined section 214 which are connected in sequence; the outer oil seal rubber body 22 is arranged on the outer walls of the fourth vertical section 212, the second horizontal section 213 and the inclined section 214; specifically, a guide inclined plane 215 is arranged on the outer side of the upper end of the third vertical section 211, and a second transition inclined plane 216 is arranged at the joint of the lower end of the third vertical section 211 and the upper end of the fourth vertical section 212; the lower end of the inclined section 214 is connected with the second horizontal section 213, and the upper end of the inclined section 214 is bent outwards to form a second flange 217. The part of the outer oil-seal rubber body 22 located in the fourth vertical section 212 is flush with the outer wall of the third vertical section 211; the portion of the outer oil seal rubber body 22 located at the second horizontal section 213 is flush with the bottom of the outer oil seal assembly 2. The part of the outer oil seal rubber body 22 located in the fourth vertical section 212 is provided with a plurality of second convex rings 221.

Referring to fig. 5, the PTFE washer 3 includes a body 31, a first dynamic lip 32, and a second dynamic lip 33, the body 31 being connected to the inclined section 214 of the outer oil seal assembly 2; one end of the first power lip 32 is connected with the body 31, and the other end of the first power lip 32 abuts against the bottom surface of the first horizontal section 113 of the inner oil seal assembly 1 to form axial self-sealing; one end of the second power lip 33 is connected to the body 31, and the other end of the second power lip 33 abuts against the inner wall of the first vertical section 111 of the inner oil seal assembly 1 to form radial self-sealing. Specifically, a connecting groove 311 adapted to the second flange 217 is disposed on a side of the body 31 opposite to the outer oil seal assembly 2, and a positioning groove 312 is disposed on a top surface of the body 31.

Referring to fig. 6, the first power lip 32 is a fluororubber power lip, and a plurality of first thread grooves 321 with arc T-shaped structures are disposed on the first power lip 32. Fluororubber power lip thread groove adopts semicircle type and T type combination to form, the area of contact of oil blanket lip and rotation axis has been reduced, behind T type contact surface radius angle R0.3mm, the actual contact surface is only 0.2 +/-0.05 mm, the pitch is 0.8 +/-0.2 mm, the thread depth is 0.35 +/-0.1 mm, the radial force of oil blanket lip has been reduced, compare with the oil blanket lip of taking the spring, the friction torque can reduce 40% -50%, the frictional heating reduces, the material ageing degree alleviates, lip "long carbon" phenomenon alleviates, life improves.

Referring to fig. 7, the second power lip 33 is a PTFE power lip, and a plurality of second thread grooves 331 with circular arc R-shaped structures are disposed on the second power lip 33. The PTFE power lip thread groove adopts an R-shaped structure with an arc; r is 0.14 +/-0.05 mm, the thread pitch is 0.5-0.6mm, the thread depth is 0.2 +/-0.06 mm, the thickness is 0.6 +/-0.1 mm, compared with the traditional polytetrafluoroethylene thread element with a T-shaped structure, the contact area between an oil seal lip and a rotating shaft is reduced, the thickness of the PTFE lip is reduced by 40%, the friction torque can be reduced by 30-50%, in addition, the thread pitch in the PTFE thread structure is changed from 0.8mm to 0.5mmm, the pumping stroke of an oil seal pump is doubled, and the sealing effect is better.

The manufacturing process of the utility model is as follows:

1. referring to fig. 8 and 9, the rubber body and the inner oil seal framework are firstly molded and vulcanized into a whole by a mold, and then the flash is cut off.

2. Referring to fig. 10 and 11, the outer oil seal assembly is obtained by integrally molding and vulcanizing the rubber body, the outer oil seal framework and the PTFE gasket by using a mold, and then performing secondary vulcanization, trimming and the like.

3. Referring to fig. 12, the outer oil seal assembly and the inner oil seal assembly are assembled together through a tool and flanged.

In the description of the specification, reference to the description of "one embodiment," "preferably," "an example," "a specific example" or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention, and schematic representations of the terms in this specification do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

With the above structure and principle in mind, those skilled in the art should understand that the present invention is not limited to the above embodiments, and all modifications and substitutions based on the present invention and adopting the known technology in the art are within the scope of the present invention, which should be limited by the claims.

Claims (10)

1. The utility model provides a commercial car engine low friction crankshaft oil blanket, includes outer oil blanket assembly (2) and interior oil blanket assembly (1), its characterized in that: also comprises a PTFE gasket (3);

the inner oil seal assembly (1) comprises an inner oil seal framework (11) and an inner oil seal rubber body (12), wherein the inner oil seal framework (11) comprises a first vertical section (111), a second vertical section (112) and a first horizontal section (113) which are sequentially connected; the inner oil seal rubber body (12) is arranged on the outer wall of the second vertical section (112);

the outer oil seal assembly (2) comprises an outer oil seal framework (21) and an outer oil seal rubber body (22), wherein the outer oil seal framework (21) comprises a third vertical section (211), a fourth vertical section (212), a second horizontal section (213) and an inclined section (214) which are sequentially connected; the outer oil seal rubber body (22) is arranged on the outer walls of the fourth vertical section (212), the second horizontal section (213) and the inclined section (214);

the PTFE gasket (3) comprises a body (31), a first power lip (32) and a second power lip (33), and the body (31) is connected with an inclined section (214) of the outer oil seal assembly (2); one end of the first power lip (32) is connected with the body (31), and the other end of the first power lip (32) abuts against the bottom surface of the first horizontal section (113) of the inner oil seal assembly (1) to form axial self-sealing; one end of the second power lip (33) is connected with the body (31), and the other end of the second power lip (33) abuts against the inner wall of the first vertical section (111) of the inner oil seal assembly (1) to form radial self-sealing.

2. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the lower end of the first vertical section (111) is bent inwards to form a first flanging (114), a first transition inclined plane (115) is arranged at the joint of the upper end of the first vertical section (111) and the lower end of the second vertical section (112), and a force returning part (116) is arranged between the upper end of the second vertical section (112) and the first horizontal section (113).

3. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the inner oil seal rubber body (12) is flush with the outer wall of the first vertical section (111).

4. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the outer side wall of the inner oil seal rubber body (12) is provided with a plurality of first convex rings (121).

5. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: a guide inclined plane (215) is arranged on the outer side of the upper end of the third vertical section (211), and a second transition inclined plane (216) is arranged at the joint of the lower end of the third vertical section (211) and the upper end of the fourth vertical section (212); the lower end of the inclined section (214) is connected with the second horizontal section (213), and the upper end of the inclined section (214) is bent outwards to form a second flanging (217).

6. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the part of the outer oil seal rubber body (22) positioned on the fourth vertical section (212) is flush with the outer wall of the third vertical section (211); the part of the outer oil seal rubber body (22) positioned at the second horizontal section (213) is flush with the bottom of the outer oil seal assembly (2).

7. The commercial vehicle engine low friction crankshaft oil seal of claim 1, characterized in that: and a plurality of second convex rings (221) are arranged at the part of the outer oil seal rubber body (22) positioned at the fourth vertical section (212).

8. The commercial vehicle engine low-friction crankshaft oil seal according to claim 5, characterized in that: one side that body (31) and outer oil blanket assembly (2) are relative is provided with spread groove (311) with second turn-ups (217) looks adaptation, and the top surface of body (31) is provided with constant head tank (312).

9. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the first power lip (32) is a fluororubber power lip, and a plurality of first thread grooves (321) with circular-arc T-shaped structures are formed in the first power lip (32).

10. The commercial vehicle engine low-friction crankshaft oil seal according to claim 1, characterized in that: the second power lip (33) is a PTFE power lip, and a plurality of second thread grooves (331) with circular arc R-shaped structures are arranged on the second power lip (33).

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