JP4748101B2 - Sliding structure and synchromesh transmission - Google Patents

Description

  The present invention relates to a sliding member, a sliding structure, and a synchromesh transmission in which a film is formed on the surface of a base material, and in particular, can reduce a friction coefficient regardless of a lubricant additive. The present invention relates to a sliding member, a sliding structure, and a synchromesh transmission.

  Conventionally, sliding members are used in various devices such as engines and transmissions in automobiles. There, various research and developments are underway to reduce the sliding resistance of the sliding member to reduce energy loss and to meet future fuel efficiency regulations for protecting the global environment.

  For example, in such research and development, in order to improve the wear resistance of the sliding member and obtain low friction characteristics, a technique for adding a solid lubricant to the lubricating oil interposed in the sliding surface of the sliding member And a technique for coating the sliding surface of the sliding member.

For example, as a technique for adding a solid lubricant to the lubricant, a technique for adding a solid lubricant such as polytetrafluoroethylene (PTFE) or molybdenum disulfide (MoS ₂ ) to the sliding surface of the sliding member can be cited. .

  In addition, as a technique for coating the sliding surface of the sliding member, as an example of a sliding member that frictionally slides, at least one friction sliding surface on which the synchronizer ring and the clutch gear frictionally slide is coated with silicon or silicon. A synchromesh type transmission in which a coating containing a compound as a main component is coated has been proposed (see Patent Document 1).

JP 2005-147337 A

By the way, the mechanism of reduction of the friction coefficient by solid lubricants such as polytetrafluoroethylene (PTFE) and molybdenum disulfide (MoS ₂ ) is due to interlayer slip caused by the layer structure of the solid lubricant, and the solid contact portion. The purpose is to reduce the shear resistance. However, such a technical area is already saturated, and it is not possible to dramatically reduce the friction coefficient compared with the current situation. Therefore, when the amount of solid lubricant added is increased in order to reduce the friction coefficient, the friction coefficient is reduced, but the wear resistance of the sliding member may be reduced.

  Furthermore, when a lubricant is supplied between the sliding members, it is desirable to reduce the shear force in the fluid layer (lubricant) in order to reduce the friction coefficient in the fluid lubrication region. In general, as a method of reducing the shear resistance in the fluid layer (lubricant), it is conceivable to use a base oil having a low traction coefficient such as polyalphaolefin (PAO), but such a base oil is used. However, it is difficult to hope for a breakthrough traction coefficient.

  Further, the synchromesh type transmission described in Patent Document 1 has a structure in which lubricating oil in a housing of the transmission is supplied to a sliding surface of a member in the housing by rotation of a gear. From such a structure, the same lubricating oil is simultaneously supplied to a plurality of sliding surfaces on which the synchronizer ring and the clutch gear are formed. However, when a lubricating oil containing an additive such as organic molybdenum or organic zinc is used as the lubricating oil, the friction coefficient between the clutch gear and the counter gear constituting the transmission is reduced by the additive. The torque loss of the transmission can be suppressed. However, when the lubricating oil is supplied to the friction sliding surfaces of the synchronizer ring and the clutch gear, the friction coefficient between these members also decreases, and the frictional force on the friction sliding surface is utilized. It becomes difficult to smoothly synchronize the synchronizer ring and the rotation of the clutch gear, and it is difficult to operate the transmission smoothly.

The present invention was made in view of such problems, and has as a first object, for example, polytetrafluoroethylene (PTFE), solid lubricants such as molybdenum disulfide (MoS ₂₎ An object of the present invention is to provide a sliding member and a sliding structure capable of obtaining a lower friction coefficient than that of a utilized sliding member. The second object is to ensure a predetermined friction characteristic without being influenced by the additive even when a lubricating oil containing an additive such as organic molybdenum and organic zinc is used. An object of the present invention is to provide a sliding member, a sliding structure, and a synchromesh type transmission.

  In order to solve the above-mentioned problems, the sliding member according to the present invention is a sliding member in which a film is formed on the surface of a substrate, and the film contains at least a titanium phosphate compound. It is said.

According to the sliding member of the present invention, the water present on the surface of the coating is decomposed by the non-catalytic action of the titanium phosphate compound to generate a hydroxyl group on the sliding surface of the sliding member on which the coating is formed. be able to. As a result, the sliding surface of the sliding member becomes a hydrophilic surface due to the hydroxyl group on the surface, and a water (H ₂ O) layer is formed on the sliding surface. Thus, when the sliding member is slid while supplying the lubricant (lubricant or grease) to the sliding surface (surface of the coating) of the sliding member according to the present invention, the sliding of the sliding member A boundary layer in which an oil layer and a water layer are mixed is formed on the moving surface. Such a boundary layer has a smaller shearing force than that of the lubricant (base oil) alone. Also, the sliding form including the boundary layer is different from the sliding form of the layered structure of the solid lubricant, and the boundary layer can reduce the shear resistance acting on the sliding member. As a result, the friction of the sliding member is less than that of the sliding member without the coating, or the sliding member using a solid lubricant (for example, a sliding member having a PTFE coating formed thereon). The coefficient can be further reduced.

  Furthermore, the sliding structure according to the present invention is a sliding structure having at least one of the sliding members and having a pair of sliding members that frictionally slide with each other. At least one of the sliding members includes a sliding surface that slides on a member different from the other sliding member of the pair of sliding members, and a surface that frictionally slides on the other sliding member. And a friction sliding surface on which a film is formed.

  According to the sliding structure according to the present invention, a film containing at least a titanium phosphate compound is formed on the surface where the pair of sliding members slide against each other without changing the surface roughness. The friction coefficient of the sliding surface sliding with respect to a member different from the sliding member and the friction coefficient of the friction sliding surface can be set to different values. As a result, a common lubricant can be supplied to the sliding members having the sliding surface and the friction sliding surface and requiring different friction characteristics. More specifically, when lubricating oil to which an additive having a high effect of reducing the friction coefficient is added is supplied to the sliding surface and the friction sliding surface, the sliding surface is subjected to friction due to adsorption of the additive. The coefficient can be reduced, and the friction sliding surface is less likely to be adsorbed by the friction sliding surface due to the formation of an aqueous layer of the titanium phosphate compound (or Even when the additive is adsorbed, the water in the water layer peels the additive from the friction sliding surface), so that the reduction of the friction coefficient due to the additive can be suppressed.

  Here, the “sliding surface” in the present invention refers to either one or both of the pair of sliding members other than the sliding surface (friction sliding surface) on which the pair of sliding members slide relative to each other. A sliding surface formed on the sliding surface that slides on a member different from the pair of sliding members. Further, the “friction sliding surface” referred to in the present invention is a sliding surface on which a pair of sliding members slide with each other by friction contact, and the sliding of the pair of sliding members using frictional force. It is a sliding surface for stopping.

  The sliding member according to the present invention more preferably includes hard particles such as aluminum oxide, silicon dioxide, aluminum nitride, or silicon nitride, or hard fibers such as carbon fiber and glass fiber in the coating. According to the present invention, the wear resistance of the coating can be improved by including the hard particles and the hard fibers in the coating.

Further, a lubricating oil containing particles such as polytetrafluoroethylene (PTFE), molybdenum disulfide (MoS ₂ ), graphite, and boron nitride may be interposed between the pair of sliding members. .

  More preferably, the sliding structure according to the present invention is configured such that a lubricant to which at least one of organic molybdenum or organic zinc is added can be supplied to the sliding surface and the friction sliding surface. According to the present invention, the lubricant to which at least one of organic molybdenum or organic zinc is added as an additive is present on the sliding surface and the friction sliding surface. The friction coefficient on the sliding surface can be reduced by adsorption of zinc, and the formation of the water layer by the titanium phosphate compound on the friction sliding surface suppresses the adsorption of organic molybdenum or organic zinc. It is possible to suppress further reduction of the friction coefficient on the moving surface.

  Examples of organic molybdenum include molybdenum-amine complexes, molybdenum-succinimide complexes, organic acid molybdenum salts, alcohol molybdenum salts, molybdenum dialkyldithiocarbamate (Mo-DTC), and molybdenum dithiophosphate (Mo-DTP). In a more preferred embodiment, the organomolybdenum compound according to the present invention is more preferably molybdenum dialkyldithiocarbamate (Mo-DTC) or molybdenum dithiophosphate (Mo-DTP).

  In particular, in consideration of versatility, cost, etc., the organomolybdenum compound contained in the lubricating oil is more preferably molybdenum dialkyldithiocarbamate (Mo-DTC), and the structure of the alkyl group in the molecule varies depending on the production method. For example, specific examples of molybdenum alkyldithiocarbamate include, for example, molybdenum dibutyldithiocarbamate, sulfurized dipentyldithiocarbamate, sulfurized dihexyldithiocarbamate, sulfurized diheptyldithiocarbamate, sulfide dioctyldithiocarbamate, dinonyldithiocarbamate. Molybdenum, molybdenum didecyl dithiocarbamate, sulfurized diundecyl dithiocarbamate, sulfurous molybdenum dododecyldithiocarbamate, molybdenum ditridecyldithiocarbamate, and the like. The organic zinc is an additive in which the molybdenum of the organic molybdenum described above is replaced with zinc, and at least the same types as those mentioned for the organic molybdenum can be mentioned.

  Further, the lubricant base oil is not particularly limited as long as it contains the additives as described above, and includes mineral oil and synthetic oil. In addition, such lubricating oils are antioxidants, antiwear agents, extreme pressure agents, friction modifiers, metal deactivators, detergents, rust preventives, foam extinguishers if the chemical reaction is not suppressed. Etc. can be added as appropriate. Note that the same effect can be obtained even when grease is obtained by further dispersing a thickener in a base oil containing organic molybdenum or organic zinc instead of the lubricating oil.

  The lubricant lubrication mechanism includes a circulation lubrication mechanism, a mist lubrication mechanism, or an oil bath lubrication mechanism using an oil bath. As long as lubricating oil can be supplied, there is no particular limitation.

  Further, the synchromesh transmission according to the present invention is a synchromesh transmission including the sliding structure, and the pair of sliding members includes a synchronizer ring and a frictional sliding on the synchronizer ring. It is a clutch gear.

  According to the present invention, at least one or both of the friction sliding surface on which the synchronizer ring and the clutch gear slide, that is, the ring inner peripheral surface of the synchronizer ring and the outer peripheral surface (gear cone surface) of the clutch gear are linked. Since a film containing a titanium acid compound is formed, the additive contained in the lubricant is difficult to adsorb on the friction sliding surface, and even when the additive is adsorbed, the additive is pulled from the friction sliding surface. It can be peeled off. As a result, it is possible to obtain a friction sliding surface that is hardly affected by the additive of the lubricant and suppresses a decrease in the friction coefficient.

  On the other hand, the synchronizer ring has a sliding surface that slides on a sleeve (a member different from the clutch gear) that moves together with the selector. Further, the clutch gear has the sleeve (a member different from the synchronizer ring) that moves together with the selector, and a sliding surface that slides with the counter gear. And since the said lubricating oil additive adsorb | sucks to these sliding surfaces, a friction coefficient is reduced.

  As described above, further reduction of the friction coefficient of the additive of the lubricant is suppressed on the friction sliding surface by the water layer resulting from the coating containing at least the titanium phosphate compound. On the other hand, the friction coefficient of the sliding surface is reduced by the additive of the lubricant. As a result, the synchronizer ring is smoothly synchronized with the rotation of the clutch gear even when the lubricating oil containing additives such as organic molybdenum and organic zinc is supplied to the friction sliding surface and the sliding surface. Further, the friction coefficient of these members can be reduced.

  According to the present invention, it is possible to obtain a lower coefficient of friction than a sliding member using a solid lubricant, and furthermore, it is possible to obtain a sliding surface that is hardly affected by the additive of the lubricating oil. Frictional properties can be ensured.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a sliding member according to an embodiment of the present invention and an embodiment of a synchromesh transmission including a sliding structure including the sliding member will be described with reference to the drawings.

  FIG. 1 is a schematic view of a sliding member according to the present embodiment, and FIG. 2 is a view showing a chemical structure of a coating film constituting the sliding member of FIG.

  As shown in FIG. 1, in the sliding member 10 according to the present invention, a coating 12 is formed on a base 11, and the base 11 is made of an iron-based material. As shown in FIG. 2, the coating 12 formed on the substrate 11 is made of a titanium phosphate compound, and the surface of the coating 12 is the sliding surface 13 of the sliding member 10. Moreover, the thickness of the film 12 is in the range of 0.5 to 5 μm. Such a coating 12 is formed by applying or spray-coating an inorganic non-photocatalytic coating agent containing the above-described composition, which is generally used for antibacterial and antifungal applications, on the surface of the substrate 11, and using an oven or the like. It can be obtained by firing for several tens of minutes under a temperature condition of about ° C. Moreover, the thickness of the said film can be adjusted with the application amount of a coating agent, and the spray amount.

  The material of the base material 11 of the sliding member 10 is an iron-based material. However, the iron-based material may be cast iron-based or steel-based. , A resin material, or a rubber material, which has a heat resistance higher than the firing temperature at the time of forming the coating, and at least a titanium phosphate compound depending on the use environment of the sliding member 10 There is no particular limitation as long as the adhesion of the coating film 12 containing can be ensured.

As shown in FIG. 1, the sliding member 10 thus configured has a sliding surface 13 on which a film containing at least a titanium phosphate compound is formed. Water is decomposed by the non-photocatalytic action of the titanium compound, and a hydroxyl group (—OH) is generated on the sliding surface 13. By the generation of the hydroxyl group, the sliding surface 13 becomes a hydrophilic surface, and a water (H ₂ O) layer is formed on the sliding surface 13. As a result, when a lubricant such as lubricating oil or grease is supplied to the sliding surface 13, a boundary layer composed of a water layer and an oil layer of the lubricant is formed. Since the boundary layer has a smaller shearing force due to the sliding of the sliding member 10 than in the case of using only the base oil, the friction coefficient of the sliding member can be further reduced.

  As described above, the sliding member 10 is effective for a sliding member that slides by supplying lubricating oil to the sliding surface. Examples of the sliding surface of the sliding member include a sliding surface between a cylinder and a piston, a sliding surface between a shaft and a slide bearing, a meshing surface between gears, and a sliding surface of a rolling bearing.

  As a preferred embodiment to which the sliding member 10 is applied, the following synchromesh transmission is shown below. FIG. 3 is a diagram schematically showing a main part of a synchromesh transmission including a synchronizer ring and a clutch gear as a pair of sliding members having the sliding member of FIG. FIG. 4 is a view for explaining a sliding structure including a synchronizer ring and a clutch gear constituting the synchromesh transmission of FIG. 3.

  As shown in FIG. 3, the synchromesh transmission 1 according to this embodiment outputs the power of an input shaft (not shown) from the engine to an output shaft (not shown) by changing the gear ratio. The transmission 1 is provided with a synchronizer ring 21 that frictionally slides and a clutch gear 22 as sliding members that operate when changing the gear ratio.

  Specifically, the synchronizer ring 21 has a cone-shaped inclined surface 21a formed on the inner peripheral surface of the ring, and teeth 21b for meshing with the sleeve 25 formed on the outer peripheral surface of the ring. On the other hand, the clutch gear 22 has a cone-shaped inclined surface (gear cone surface) 22a, a tooth 22b for meshing with the sleeve 25, and a gear 22c for meshing with a counter gear (not shown) for power transmission. Is formed.

  A film containing at least a titanium phosphate compound is formed on the inner inclined surface (ring inner peripheral surface) 21a of the synchronizer ring 21 and the gear cone surface 22a of the clutch gear 22, and these members will be described later. As described above, the operation of the selector 26 causes frictional sliding with each other.

  The “friction sliding surface” according to the present invention corresponds to the inclined surface 21 a of the synchronizer ring 21 and the gear cone surface 22 a of the clutch gear 22 in the present embodiment. Further, the “sliding surface” according to the present invention includes the sliding surface of the tooth 21b that slides with the sleeve 25 of the synchronizer ring 21 and the sliding surface of the tooth 22b that slides with the sleeve 25 of the clutch gear 22 in the present embodiment. This corresponds to the sliding surface of the gear 22c sliding with the sleeve 25 of the clutch gear 22 and the sliding surface (tooth surface) of the gear 22c sliding with the counter gear of the clutch gear 22. And the transmission 1 which concerns on this embodiment added the organic molybdenum or the organic zinc by rotation of the counter gear to these friction sliding surfaces and sliding surfaces similarly to the transmission of a general synchromesh system. The lubricating oil can be supplied.

  When shifting using such a transmission 1, the sleeve 25 connected to the selector 26 is moved in the axial direction of the shaft 27 so that the cone-shaped inclined surface 21a of the synchronizer ring 21 is moved to the clutch gear. The rotation of the synchronizer ring 21 and the clutch gear 22 is synchronized by frictional contact with the gear cone surface 22a of 22 and frictional force. Further, the sleeve 25 is further moved in the same direction so that the sleeve 25 comes into contact with the teeth 21 b of the synchronizer ring 21, thereby synchronizing the rotation of the sleeve 25 and the synchronizer ring 21. In this way, the synchronizer ring 21, the clutch gear 22, and the sleeve 25 are synchronized in rotation, so that the sleeve 25 meshes with the teeth 21b of the synchronizer ring 21 and the teeth 22b of the clutch gear 22, and engages with the gear 22c of the clutch gear 22. The power from the counter gear is transmitted.

  At this time, the organic molybdenum or organic zinc contained in the lubricating oil is adsorbed on the sliding surfaces of the synchronizer ring 21 and the clutch gear 22, and the sliding characteristics related to these sliding surfaces are improved. In particular, the coefficient of friction between the clutch gear 22 and the counter gear is reduced by adsorbing organic molybdenum or organic zinc to the tooth surface of the gear 22c that meshes with the counter gear with respect to the clutch gear 22 among the sliding surfaces. The As a result, torque loss from the engine in the transmission 1 can be reduced.

  On the other hand, a lubricant containing organic molybdenum or organic zinc is also supplied between the inclined sliding surface 21a of the synchronizer ring 21 and the friction sliding surface which is the gear cone surface 22a of the clutch gear 22, and between these friction sliding surfaces. Will intervene. However, since a coating film containing at least a titanium phosphate compound is formed on these friction sliding surfaces, a hydroxyl group is generated on the surface of the titanium phosphate compound. As a result, the surface of the coating film having become hydrophilic becomes a hydrophilic surface, and an aqueous layer is formed on the surface. This makes it difficult for organic molybdenum or organic zinc to be adsorbed on the frictional sliding surface, and even if they are adsorbed, the water layer peels off these additives, further reducing the friction coefficient on the frictional sliding surface. The As a result, the rotation of the synchronizer ring 21 and the clutch gear 22 can be smoothly synchronized.

Hereinafter, the present invention will be described by way of examples.
[Example 1]
(Sliding structure)
As a pair of sliding members, a disk test piece and a ring test piece are prepared in order to perform a ring-on-disk test described later, and the disk test piece, the ring test piece, and these test pieces are used as a sliding structure. A lubricating oil interposed between them was prepared.

<Disk specimen>
As shown in FIG. 5, as a base material for forming a film containing a titanium phosphate compound, a carbon steel material for mechanical structure (S45C: 30 mm × 30 mm × 5 mm) having a surface roughness of centerline average roughness Ra of 0.2 μm. JIS standard, quenching and tempering), and applying a stock solution of a commercially available inorganic non-photocatalytic coating agent (Eco Chimera CW-30, Techno Trade) for antibacterial, deodorant and antifungal applications on the surface of 30 mm x 30 mm The coated substrate was baked in an oven at 200 ° C. for 30 minutes, and the film containing a titanium phosphate compound was formed on the sliding surface of the disk specimen so that the film thickness was in the range of 0.5 to 5 μm. Formed.

<Ring specimen>
As shown in FIG. 5, a ring test piece made of material SAE4620 having an outer diameter of 25.6 mm, an inner diameter of 20 mm, a height of 16 mm, and a center line average roughness Ra of 0.25 μm was manufactured.

<Lubricating oil>
A lubricating oil in which only an antioxidant was added to the base oil (engine oil 150N) was prepared.

(Friction test)
As shown in FIG. 5, the peripheral speed of 0.3 m / sec was supplied while supplying the lubricating oil heated to 80 ° C. by bringing the 30 mm × 30 mm surface of the disk test piece into contact with the cylindrical end surface of the ring test piece. The surface pressure was changed from 5 MPa to 10 MPa, a running-in test was performed, and a friction test was performed for 60 minutes under a constant load of 10 MPa, and the change with time of the friction coefficient was evaluated. The result is shown in FIG.

[Comparative Example 1]
A disk test piece and a ring test piece were produced in the same manner as in Example 1, and a friction test was performed under the same conditions as in the example. The difference from the example is that a film containing a titanium phosphate compound was not formed on the surface of the disk test piece. The result is shown in FIG.

[Comparative Example 2]
A disk test piece and a ring test piece were produced in the same manner as in Example 1, and a friction test was performed under the same conditions as in the example. The difference from the examples is that a film of polytetrafluoroethylene (PTFE), which is a solid lubricant, is provided on the surface of the disk test piece instead of the film containing the titanium phosphate compound. The result is shown in FIG.

[Result 1]
The friction coefficient decreased in the order of Example 1, Comparative Example 2, and Comparative Example 1.

[Discussion 1]
Since the titanium phosphate compound coating is formed on the sliding surface of Example 1, H ₂ O is adsorbed on the sliding surface by the catalytic action of titanium phosphate, and the H ₂ O layer and the lubricant are lubricated. It is thought that a boundary layer in which the oil layer of oil was mixed was formed. As a result, the shearing force of the boundary layer was reduced during sliding, and the coating of Polytetrafluoroethylene (PTFE), which is the solid lubricant of Comparative Example 2, was not slid. It is considered that the friction coefficient is further reduced as compared with that formed on the moving surface.

[Example 2]
<A pair of sliding members>
As shown in FIG. 4, a synchronizer ring 21 and a clutch gear 22 of a transmission are prepared as a pair of sliding members, a cone-shaped inclined surface (inner peripheral surface) 21 a of the synchronizer ring 21, and a gear cone of the clutch gear 22. The surface 22a is coated with a stock solution of a commercially available inorganic non-photocatalytic coating agent (Eco Chimera CW-30, Techno Trade) for antibacterial, deodorant and antifungal applications, and the coated substrate is baked in an oven at 100 ° C. for 30 minutes A film containing a titanium phosphate compound was formed on these surfaces 21a and 22a so as to have a film thickness of 0.5 to 5 μm.

<Lubricating oil>
As lubricating oil supplied into the transmission, gear oil (API: GL-5, SAE: 75W-90), 1000 ppm of organic molybdenum (molybdenum alkyldithiocarbamate: Mo-DTC (manufactured by ADEKA, Sakuralubu 100: dihexyl dithiocarbamic acid) A lubricating oil to which (equivalent to molybdenum sulfide) was added was prepared.

<Friction test>
The synchronizer ring and the clutch gear are prepared, the lubricant is kept constant at 50 ° C., and the synchronizer ring is pressed against the clutch gear rotating at a constant speed of 1200 rpm with a pressing load of 700 N. the torque transmitted is measured 10 ^four times, to calculate the coefficient of dynamic friction from the measurement results. The result is shown in FIG.

<Torque loss ratio measurement test>
The synchronizer ring and clutch gear are mounted on a manual transmission (synchromesh type transmission) for a 5-speed FF vehicle, the input rotational speed of the transmission is 1000 rpm, and the temperature of the lubricating oil is constant at 50 ° C. Then, after running-in operation and pattern shifting, 5 speeds were continued for 5 hours, the loss torque of the transmission was measured, and the torque loss ratio was obtained. The torque loss ratio is a ratio calculated based on the loss torque measured when the titanium phosphate coating is not formed and organic molybdenum is not added to the lubricant. The result is shown in FIG.

[Comparative Example 3]
In the same manner as in Example 2, a synchronizer ring and a clutch gear were prepared. The difference from the second embodiment is that a film containing a titanium phosphate compound is formed on the cone-shaped inclined surface (inner peripheral surface) 21a of the synchronizer ring 21 and the gear cone surface 22a of the clutch gear 22 shown in FIG. This is a point where no organic molybdenum is added to the lubricating oil. In the same manner as in Example 2, a friction test and a torque loss ratio measurement test were performed. The results are shown in FIGS.

[Comparative Example 4]
In the same manner as in Example 2, a synchronizer ring and a clutch gear were prepared. The difference from the second embodiment is that a film containing a titanium phosphate compound is formed on the cone-shaped inclined surface (inner peripheral surface) 21a of the synchronizer ring 21 and the gear cone surface 22a of the clutch gear 22 shown in FIG. It is a point that has not been done. In addition, organic molybdenum is added to the lubricating oil. A friction test was performed in the same manner as in Example 2. The result is shown in FIG.

[Result 2]
As shown in FIG. 7, the friction coefficients of Example 2 and Comparative Example 3 are substantially the same, and are larger than those of Comparative Example 4. Further, as shown in FIG. 8, the torque loss ratio in Example 2 was smaller than that in Comparative Example 3.

[Discussion 2]
From the result 2, as in Comparative Example 4, when organic molybdenum is simply added to the lubricating oil, these additives adhere to the inclined surface (inner peripheral surface) of the synchronizer ring and the gear cone surface of the clutch gear, It is thought that the friction coefficient was lowered. As a result, when the synchronizer ring and the clutch gear whose surface is not processed are used and the lubricating oil to which organic molybdenum is added is used, there is a possibility that the synchronizer ring and the clutch gear may be out of synchronization when the transmission is shifted. it is conceivable that.

  On the other hand, the lubricant to which organic molybdenum is added is also interposed between the inclined surface of the synchronizer ring of Example 2 and the frictional contact surface which is the gear cone surface of the clutch gear. However, a coating containing a titanium phosphate compound is formed on these friction sliding surfaces, so that a hydroxyl group is generated on the surface of the titanium phosphate compound, and an aqueous layer is formed on the friction sliding surface. It is thought that it is done. As a result, organic molybdenum is difficult to adsorb on the friction sliding surface, and even if they are adsorbed, the water in the water layer peels off the organic molybdenum, so further reduction of the friction coefficient on the friction sliding surface is suppressed, and a comparative example It is considered that the friction coefficient was equivalent to 3. As a result, in the case of Example 2, it is considered that the synchronizer ring and the rotation of the clutch gear can be smoothly synchronized.

  Furthermore, since Example 2 added organic molybdenum to the lubricating oil unlike Comparative Example 3, for example, a lubricating oil in which organic molybdenum was added to the sliding surface of the transmission such as the meshing surface of the clutch gear and the counter gear. Is supplied. As a result, the meshing loss between the clutch gear and the counter gear is reduced, and compared to the third comparative example, the second embodiment can reduce the torque loss as a transmission unit.

  As mentioned above, although embodiment of this invention has been explained in full detail using drawing, a concrete structure is not limited to this embodiment, Even if there is a design change in the range which does not deviate from the gist of the present invention. These are included in the present invention.

  For example, in this embodiment, it can be used for a synchronizer ring and a clutch gear of a synchromesh transmission, but the sliding surface is required to have an effect of reducing the coefficient of friction by organic molybdenum or organic zinc, and the sliding It is suitable for a member constituting a synchromesh mechanism having a sliding surface (friction sliding contact surface) that requires a higher friction coefficient than the surface, and its application location is not particularly limited. Absent. For example, a member such as a one-way clutch can be used.

The schematic diagram of the sliding member which concerns on this embodiment. The figure which showed the chemical structure of the film which comprises the sliding member of FIG. FIG. 2 is a schematic view of a main part of a synchromesh transmission including a synchronizer ring and a clutch gear as a pair of sliding members having the sliding member of FIG. 1. The figure for demonstrating the sliding structure containing the synchronizer ring and clutch gear which comprise a pair of sliding member of the synchromesh type transmission of FIG. Schematic for demonstrating a friction characteristic test. The figure which showed the friction test result of Example 1 and Comparative Examples 1 and 2. FIG. The figure which showed the friction test result of Example 2 and Comparative Examples 3 and 4. FIG. The figure which showed the result of the loss torque ratio of Example 2 and Comparative Example 3. FIG.

Explanation of symbols

  1: Transmission, 10: Sliding member, 11: Base material, 12: Coating, 13: Sliding surface, 21: Synchronizer ring, 21a: Inclined surface, 21b: Teeth (meshing with sleeve), 22: Clutch gear, 22a: gear cone surface (inclined surface), 22b: tooth (meshing with sleeve), 22c: gear (meshing with counter gear), 25: sleeve, 26: selector, 27: shaft

Claims (2)

Mutually a sliding structure with a pair of sliding members in frictional sliding,
One slide member of the pair of slide members, the other sliding member different member and the sliding surfaces of the pair of sliding members, a sliding surface made of an iron-based material,
A friction sliding surface on which a film containing a titanium phosphate compound is formed on a surface that frictionally slides with the other sliding member ;
The sliding structure is configured so that a lubricant to which at least one of organic molybdenum or organic zinc is added can be supplied to the sliding surface and the friction sliding surface. . A synchromesh transmission having the sliding structure according to claim 1 ,
The pair of sliding members are a synchronizer ring and a clutch gear that frictionally slides on the synchronizer ring.

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