[0055] Hereinafter, an embodiment of the present invention will be described based on the drawings. Figures 1 to 6 show the first embodiment of the present invention. The ball bearing has: outer wheel A 1 , Inner wheel A 2 , In the outer wheel A 2 And inner wheel A 2 A plurality of balls B assembled in between, a retainer C holding the balls B. As shown in FIGS. 3 to 5, the retainer C is composed of two ring bodies 1 and 1, and each ring body 1 is formed into the same shape by synthetic resin molding. In addition, in outer wheel A 1 And inner wheel A 2 The annular space formed therebetween is shown in Fig. 1, and is sealed with a bearing gasket D and sealed with grease.
[0056] As shown in FIGS. 2 to 4, the ring body 1 has a plurality of hemispherical ball holding portions 2 and a plurality of plate-shaped joint portions 3, and the ball holding portions 2 and the joint portions 3 are alternately formed in the circumferential direction. The ball holding portion 2 is provided with a recess 4 that opens to one side surface of the ring body 1. The inner surface of the recess 4 constitutes a hemispherical surface along the outer circumference of the ball B.
[0057]The coupling part 3 is formed with an engaging hole 5 penetrating both sides and an engaging claw 6 inserted into the engaging hole 5 of the other ring body 1, and an engaging step is provided on the inner periphery of the engaging hole 5 7. On the other hand, a hook portion 8 capable of engaging with the engaging step portion 7 is formed at the tip portion of the engaging claw 6, and an end surface of the hook portion 8 in the retainer circumferential direction forms an inclined surface 9.
[0058] The engagement of the engagement hole 5 and the engagement claw 6 is to form a gap in the radial direction of the retainer between the engagement hole 5 and the engagement claw 6 at the initial stage of assembly of the retainer, and make the retainer diameter at the end of the retainer assembly. The direction gap is 0 or less. In order to achieve this kind of fitting, the width dimension E of the engaging claw 6 in the radial direction of the holder is set to be equal to or greater than the width dimension e of the engaging hole 5 in the radial direction of the holder. 1 (E≥e 1 ), and at the same time, tapered surfaces 10 with the tip of the engaging claw 6 as a small end surface are formed on both side surfaces in the radial direction of the holder at the front end of the engaging claw 6.
[0059] In addition, in order to facilitate the insertion of the engaging claw 6 into the engaging hole 5, the width dimension F of the engaging claw 6 in the circumferential direction of the holder is set to be less than or equal to the width dimension f of the engaging hole 5 in the circumferential direction of the holder. 1 (F≤f 1 ), and at the same time, a tapered surface 11 is formed at the front end of the end surface of the engaging claw 6 in the circumferential direction.
[0060] In the ring-shaped body 1 formed by the above-mentioned structure, if the two ring-shaped bodies 1, 1 are arranged in the axial direction so that the recesses 4 face each other, a plurality of ring-shaped bodies 1 are formed. The engaging claw 6 is opposed to the engaging hole 5 formed on the other ring body 1. Then, if the two ring bodies 1, 1 are moved in a direction approaching each other, the engagement claw 6 starts to enter the engagement hole 5, and the two ring bodies 1, 1 are relatively moved until their side faces overlap. At this time, the hook portion 8 of the engaging claw 6 engages with the engaging step portion 7, and the two ring bodies 1 and 1 are integrated into one body, thereby assembling the retainer C.
[0061] When assembling the ball bearing using the retainer C, the outer ring A 1 And inner wheel A 2 After inserting the same number of balls B as the recesses of the retainer C, insert the two ring bodies 1, 1 into the annular space formed between the two wheels from both sides in the axial direction of the two wheels to engage The claw 6 engages with the engaging hole 5. Grease is sealed in the annular space formed between the two wheels, and bearing seals are installed at the openings at both ends of the annular space.
[0062] When assembling the retainer C as described above, the width dimension E of the engaging claw 6 in the radial direction of the retainer is greater than or equal to the width dimension e of the engaging hole 5 in the radial direction of the retainer. 1 Therefore, in the engaged state of the engagement pawl 6 shown in FIG. 6, the clearance between the engagement pawl 6 and the engagement hole 5 in the retainer radial direction is set to be less than zero.
[0063] Therefore, even if an axial load is applied to the retainer C due to the lag or advance of the ball B when the bearing rotates, the engagement portion between the hook portion 8 of the engagement pawl 6 and the engagement step portion 7 of the engagement hole 5 will not Sliding occurs, and it is possible to control the temperature increase of the ball bearing caused by the heat generated in the engaging portion.
[0064] In addition, it is possible to prevent the occurrence of abrasion in the engagement portion of the engagement pawl 6, and it is possible to prevent the occurrence of a decrease in bearing life and noise caused by the biting of abrasion powder.
[0065] Furthermore, tapered surfaces 10 are provided on the front ends of both side surfaces of the engaging claw 6 in the radial direction of the retainer, so that the front end of the engaging claw 6 has a larger width E in the radial direction of the retainer than that of the engaging hole 5 in the radial direction of the retainer. The width dimension e 1 Because of the small size, the engagement claw 6 can be easily inserted into the engagement hole 5, and the holder C can be easily assembled.
[0066] Figures 7 and 8 show the second embodiment of the present invention. The cage shown in this embodiment is incorporated in the same ball bearing as the ball bearing shown in FIG. 1. The difference from the retainer C shown in FIGS. 1 to 6 is the fitting relationship between the engagement claw 6 and the engagement hole 5. Therefore, the same components as those of the retainer C shown in FIGS. 1 to 6 are assigned the same reference numerals, and their description is omitted.
[0067] In this second embodiment, the width dimension E of the engagement claw 6 in the radial direction of the holder is set to be greater than or equal to the width dimension e of the engagement hole 5 in the radial direction of the holder. 2 (E≥e 2 ), the two side surfaces of the engaging hole 5 on the entrance side of the engaging pawl 6 are extended to the entrance side, and the taper surface 12 whose opposing interval gradually increases.
[0068] In the second embodiment described above, in the initial stage of assembly of the retainer C that joins the two ring bodies 1, 1, because it is also possible to insert the tip of the engaging claw 6 into the engaging hole 5 with a certain allowance, Therefore, the holder C can be easily assembled.
[0069] In addition, in the state of assembling the retainer C in which the engaging claws 6 and the engaging holes 5 are engaged, the gap between the engaging claws 6 and the engaging holes 5 in the radial direction of the retainer can be set to 0 or less. It is possible to prevent the hook portion 8 of the engaging claw 6 from sliding along the engaging step portion 7 due to a radial load applied to the retainer C, and to prevent abrasion of the engaging claw 6 at the engaging portion.
[0070] Figures 9 to 11 show the third aspect of the present invention. The cage shown in this embodiment is incorporated in the same ball bearing as the ball bearing shown in FIG. 1. The only difference from the retainer C shown in FIGS. 1 to 6 is the configuration of the fitting portion of the engagement claw 6 and the engagement hole 5.
[0071] Therefore, the same components as those of the retainer C shown in FIGS. 1 to 6 are assigned the same reference numerals, and their description is omitted.
[0072] In the third embodiment, the width dimension E of the engaging claw 6 in the radial direction of the holder is set to be smaller than the width dimension e of the engaging hole 5 in the radial direction of the holder. 3 (E 3 ), and an engaging groove 13 extending in the insertion direction of the engaging claw 6 is provided on the back of the surface of the engaging claw 6 on which the hook 8 is formed, and on both sides of the front end of the engaging groove 13 Create a cone 14.
[0073] On the other hand, on the engaging hole 5, an engaging claw 6 is provided on the inner surface facing the engaging step portion 7 to fit into the engaging groove with a certain amount of interference when inserted into the engaging hole 5. 13 of the engaging protrusion 15, and tapered surfaces 16 are formed on both sides of the front end of the engaging protrusion 15.
[0074] As described above, when the engaging groove 13 is formed on the engaging claw 6 and the engaging protrusion 15 is provided on the inner surface of the engaging hole 5, the engaging claw 6 is inserted into the engaging hole 5 to insert the two ring bodies 1 In the assembled state of the coupled retainer C, the engaging protrusion 15 is fitted into the engaging groove 13. At this time, since the engagement of the engagement protrusion 15 and the engagement groove 13 is performed by interference fitting, the engagement of the engagement protrusion 15 and the engagement groove 13 can prevent engagement The hook portion 8 of the claw 6 slides along the engagement step portion 7 in the holder radial direction, and the abrasion of the engagement portion of the engagement claw 6 can be prevented.
[0075] In addition, by setting the width dimension E of the engaging claw 6 to be larger than the width dimension e of the engaging hole 5 3 Since it is small, the engaging claw 6 can be easily inserted into the engaging hole 5, and the holder C can be easily assembled.
[0076] Figures 12 to 14 show the fourth embodiment of the present invention. The retainer shown in this embodiment is incorporated in the same ball bearing as the ball bearing shown in FIG. 1, an engaging protrusion 15 is provided on the side surface of the engaging pawl 6, and an engaging groove is formed on the inner surface of the engaging hole 5. 13. Only the above point is different from the retainer C shown in Figs. 9-11. Therefore, the same components as those of the retainer C shown in FIGS. 9 to 11 are assigned the same reference numerals, and their description is omitted.
[0077] The retainer of the fourth embodiment described above can also achieve the same effect as the retainer shown in the third embodiment.
[0078] In addition, in the third embodiment and the fourth embodiment, the taper surfaces 14, 16 are provided on both sides of the entrance portion of the engaging groove 13 and the front end portion of the engaging protrusion 15, but it may be only in the engaging groove 13 A tapered surface is provided on one of the engaging protrusions 15.
[0079] The two ring bodies 1, 1 in the holders of the first to fourth embodiments described above are preferably made of polyamide 46 (hereinafter referred to as PA46) or polyamide 66 (hereinafter referred to as PA66) as a base material, and 10 ~40% by weight of fibrous reinforcing materials are made of composite materials. If the blending weight of the reinforcing material is 10% by weight or more, the strength of the retainer C can be ensured even in a high-temperature, high-speed rotation state. On the other hand, if the blending weight of the reinforcing material is 40% by weight or less, it is possible to suppress the decrease in the melt viscosity to improve the formability, and it is possible to prevent insufficient strength of the welded portion.
[0080] As the fibrous reinforcing material, for example, glass fiber, carbon fiber, aramid fiber, potassium titanate fiber, alumina fiber, silicon carbide fiber, aluminum fiber, boron fiber, etc. can be used, but glass fiber and carbon fiber are particularly preferred. , Aromatic polyamide fiber. These fibers can also be used in combination of two or more kinds.
[0081] In addition, the average fiber diameter of the fibrous reinforcing material is preferably from 1 to 20 μm, and the average fiber length is more preferably from 0.1 to 5 mm.
[0082] Furthermore, these fibers are preferably surface-treated with a silane-based, titanium-based or aluminum-based coupling agent to increase the affinity with the polycyanoaryl ether. This promotes the combination of the fiber and the polycyanoaryl ether, and improves the strength of the retainer C.
[0083] When glass fiber is used as a reinforcing material, it is particularly preferable to set the compounding amount to 20 to 30% by weight, and when carbon fiber is used, it is particularly preferable to set the compounding amount to 20 to 35% by weight.
[0084] In addition, when glass fiber is used as a reinforcing material, it is preferable to use a substance having an aspect ratio (ratio of average fiber length to average fiber diameter) of 10 or more.
[0085] If PA46 is used as the base material, compared with the case of using PA66 as the base material, a retainer with excellent heat resistance and durability can be obtained. However, when PA46 is used as the base material, it is preferable to use a rubber-like elastic Elastomer. This facilitates assembly of the cage C to the bearing. As the elastomer, ethylene propylene rubber is suitable, and its compounding amount is preferably 2 to 10% by weight, more preferably 2 to 6% by weight. If the compounding amount of ethylene propylene rubber is 2% by weight or more, good assemblability of the retainer C can be ensured. By setting the compounding amount of ethylene propylene rubber to 10% by weight or less, more preferably 6% by weight or less, Suppress the deterioration of heat resistance and moldability caused by blending ethylene propylene rubber.
[0086] The formation of the ring body 1 can be carried out as follows, for example.
[0087] The particles of PA46 or PA66 and the fibrous reinforcing material are mixed and stirred in a mixer, and then melted and mixed at 350-400°C, preferably 360-380°C with a two-screw extruder to granulate them. The obtained pellets are injection-molded under the conditions of a resin temperature of 350 to 390° C. and a metal mold temperature of 150 to 230° C. to form the ring body 1.
[0088] In addition, the PA46 or PA66 particles and fibrous reinforcing material can be mixed in a mixer and the mixture can be made into a cylindrical or cylindrical molded product with a press extruder or the like, and the resulting molded product can be cut Processed to form the ring body 1.
[0089] Furthermore, a thermal stabilizer, solid lubricant, lubricating oil, colorant, anti-static agent, mold release material, fluidity improving material, crystallization accelerator, etc. may be added to the composite material forming the ring body 1.
[0090]Similarly, the two ring bodies 1 and 1 constituting the retainer C of the first to fourth embodiments described above can also be made of polyphenylene sulfide (hereinafter referred to as PPS) as the base material, with 10-40% by weight A composite material made of fibrous reinforcing materials. If PPS is used as the base material, compared with the case of using PA as the base material, a retainer having excellent heat resistance, oil resistance, and chemical resistance can be obtained. In particular, if a linear PPS is used, the toughness of the retainer can be improved as compared with the case of using a cross-linked PPS, which is preferable. For the reinforcing material, if the blending amount is 10% by weight or more, the amount of PPS can be reduced and the cost of the retainer can be reduced. If the blending amount is 40% by weight or less, the deformation of the retainer can be ensured. It is capable of preventing damage to the engaging claw 6 during assembly.
[0091] When carbon fiber is used as a reinforcing material, it is particularly preferable to set the compounding amount to 20 to 35% by weight.
[0092] As for the glass fiber used as the reinforcing material, the average fiber diameter is preferably 5 to 20 μm, and the average fiber length is preferably 0.2 to 1 mm.
[0093] It is also possible to add 10 to 25% by weight of an inorganic filler to the composite material forming the ring body 1, thereby reducing the amount of PPS and reducing the cost of the retainer. If the addition amount is 10% by weight or more, the effect as a filler can be reliably obtained, and if the addition amount is 25% by weight or less, the cage can be easily molded. Examples of inorganic fillers include powders and granules of calcium carbonate with a thickness of 10 μm or less.
[0094] In addition, an organic reinforcing material, lubricant, plasticizer, flame retardant, etc. may be added to the composite material forming the ring body 1.
[0095] Similarly, the two ring bodies 1, 1 constituting the retainer C of the first to fourth embodiments described above can also be used for polyimide (hereinafter referred to as PI) or polyether ether ketone (hereinafter referred to as PEEK). ) As a base material, a composite material of 10-40% by weight of a fibrous reinforcing material is blended. If PI or PEEK is used as the base material, its heat resistance is superior compared to the case of using PA, and it can be used in a high temperature environment higher than 150°C. For reinforcing materials, if the blending amount is set to 10% by weight or more, the amount of PI or PEEKS can be reduced, and the cost of the retainer can be reduced. If the blending amount is set to 40% by weight or less, it can ensure The deformability of the retainer can prevent breakage of the engaging claw 6 during assembly.
[0096] When glass fiber is used as a reinforcing material, it is particularly preferable to set the compounding amount to 20 to 40% by weight, and more preferably to 20 to 35% by weight. In addition, when carbon fibers are used, it is particularly preferable to set the blending amount to 20 to 30% by weight.
