CN100462582C

CN100462582C - Rolling bearing having superthin wall

Info

Publication number: CN100462582C
Application number: CNB2003101182507A
Authority: CN
Inventors: 平松研吾
Original assignee: NTN Corp
Current assignee: NTN Corp
Priority date: 2003-12-08
Filing date: 2003-12-08
Publication date: 2009-02-18
Anticipated expiration: 2023-12-08
Also published as: CN1626841A

Abstract

The invention relates to a rolling bearing with ultrathin wall. It includes an internal ring, an external ring, several rolling components set between the tracking surfaces of internal ring and external ring and a retainer made of resin material. Said invention also provides the concrete structure and design requirement of the above-mentioned every component. Said invented rolling bearing with ultrathin wall has the function of preventing generation of abnormal sound.

Description

Rolling bearing with ultra-thin-wall

Technical field

The present invention relates to a kind of rolling bearing that is used on industrial robot, lathe, medical apparatus and the similar device with ultra-thin-wall, particularly, particularly relate to and a kind ofly be used to make the segmented resin retainer that is installed in the ultrathin wall rolling bearing to keep the device of stable performance, its objective is and to reduce the friction noise that when retainer and bearer ring are in contact with one another, is produced.

Background technique

See also shown in Figure 8ly, demonstrated the example of a CT scan device, this CT scan device is a kind of medical apparatus.In this CT scan device, the X ray that is produced by X-ray tube parts 50 acts on human body by a slit 52 that is used to make the equally distributed wedge filter 51 of transmitted intensity and to be used to limit intensity distriubtion.The X ray that sees through human body 53 is accepted by a prober 54, and in this prober 54, X ray is converted into an electrical signal, and then, this electrical signal is imported into again in the not shown computer.These X-ray tubes 50, wedge filter 51, slit 52 and prober 54 such parts are mounted on one and are roughly on the columnar rotating frame 57, and this rotating frame 57 is supported on the fixed frame 56 rotationally by a bearing 55, drives and make the parts around the human body 53 to rotate by the rotation of rotating frame 57.In this CT scan device, X-ray tube 50 that is oppositely arranged and prober 54 provide some projection data around the rotation of human body 53, these data have covered all angles in the inspection cross-section of human body 53, and can utilize the reproducing program by finishing in advance to obtain tomographic image by these data.

In this CT scan apparatus, the structural type that makes its size can hold human body 53 that is manufactured in interior week owing to fixed frame 56, therefore, one for diameter, bearing that its cross sectional area is minimum or so-called ultra-thin-wall bearing just are used as the bearing 55 between fixed frame 56 and rotating frame 57.

For the ultra-thin-wall rolling bearing in being commonly used in the CT scan apparatus, its retainer (or bearing cage) is formed from a resin.This retainer that is formed from a resin is that the structural type with a plurality of arcuate segments exists, and these arcuate segments link together in the form of a ring, and wherein adjacent segmentation is assembled together by the cooperation of projection and groove in its end.Each segmentation all is parts of making through injection moulding, and fiber reinforced polyamide resin (PA66) is often used as the raw material of these parts.This PA66 has bigger coefficient of linear expansion than Bearing Steel, and Bearing Steel is exactly to make the used a kind of material of raceway; And PA66 has following characteristic: its difference in size increases with variation of temperature, perhaps expands because of suction.Therefore, for large-scale bearing, the girth of retainer will change a lot.When all segmentations were linked together, the perimeter change of retainer can be eliminated the guiding clearance between retainer and the raceway; Therefore, this retainer just need be installed with a clearance G (notconnect state) (as shown in figure 10) in use on a position, rather than all segmentations are all linked together.

The prior art of this ultrathin wall rolling bearing, for example open in Japanese Patent Application 2000-329143,2001-304266 and 2002-81442.

Because these are made of resin and the segmentation of forming a retainer is the parts of making through injection moulding, like this, the anastomosis part between projection and groove fit part just may be owing to the error in the mold process produces loosening.Should loosening cooperation can between

adjacent segmentation

410 and 420, produce dislocation, as shown in Figure 9, there is shown the situation that right side part 420 radially misplaces inwards.

Seeing also shown in Figure 9ly, is the structure sectional view that the retainer of ultrathin wall rolling bearing appears at the inconsistent phenomenon in the assembly area of segmentation.The retainer 400 of this ultrathin wall rolling bearing generally is to use with a raceway guiding element; In Fig. 9, show the situation that adopts a kind of outer shroud guiding element.This retainer by raceway guiding radially be subjected to the raceway retainer guide surface (inside diameter surface of outer shroud or the external diameter surface of interior ring) guiding (to the heart) and be suitable between the external diameter surface (or inside diameter surface) of the retainer guide surface of raceway and retainer, leaving suitable radial clearance, thereby can prevent that retainer from rotating.When bearing rotates, the driving force that retainer passes through to receive from outer shroud 100, interior ring 200 or rolling member 300 with the difference of guidance system produces rotation, radially move in the scope of guiding clearance S in retainer simultaneously, this gap is to be represented by mark S in Fig. 9.Therefore, for the retainer of outer shroud guidance type, for example, when in segmentation 420, producing dislocation, as shown in Figure 9, rotation along with retainer 400, the end 421 of this segmentation 420 contacts with the periphery of interior ring 200, and in normal circumstances, this end 421 should not contact with the periphery of interior ring (being referred to as " contacting unusually " hereinafter), and this unusual contact is again a factor that produces abnormal sound sometimes, for example raps sound and chatter.

In addition, because the difference of bearing internal void and service condition is different, rolling member may occur moving in advance or delay-action problem.See also shown in Figure 10, if it is the same with prior art, retainer will reserved a clearance G (under the notconnect state) in use on a certain position, rather than all these segmentations are linked together, the action in advance or the delay voltage of rolling member all can make the unstable properties of retainer so, so just be easy to generate the sound of friction or the sound that raps, wherein Mo Ca sound produces when retainer and raceway are in contact with one another, and the sound that raps is to produce when the part of join domain is not knocked raceway being positioned at.Bearing is used for be used to needing at a high speed on the CT scan device or with bearing, on the similar device of noise free rotation the time, this grating just becomes a problem.

This shows that the rolling bearing of above-mentioned existing ultra-thin-wall type still has defective, and demands urgently further being improved.The problem that exists for the rolling bearing that solves the ultra-thin-wall type, relevant manufacturer there's no one who doesn't or isn't seeks solution painstakingly, but do not see always that for a long time suitable design finished by development, and common product does not have appropriate structure to address the above problem, and this obviously is the problem that the anxious desire of relevant dealer solves.

Because the defective that the rolling bearing of above-mentioned existing ultra-thin-wall type exists, the inventor is based on being engaged in this type of product specification manufacturing abundant for many years practical experience and professional knowledge thereof, actively studied innovation, in the hope of founding a kind of novel rolling bearing with ultra-thin-wall, can improve the rolling bearing of general existing ultra-thin-wall type, make it have more practicability.Through constantly research, design, and after studying sample and improvement repeatedly, create the present invention who has practical value finally.

Summary of the invention

The objective of the invention is to, overcome the defective of the rolling bearing existence of existing ultra-thin-wall type, and provide a kind of rolling bearing of new structure with ultra-thin-wall, technical problem to be solved is to make it can prevent or stop under the situation of using the ultra-thin-wall rolling bearing and produce abnormal sound, thereby be suitable for practicality more, and have the value on the industry.

The object of the invention to solve the technical problems realizes by the following technical solutions.A kind of rolling bearing according to the present invention's proposition with ultra-thin-wall, it comprises ring in, an outer shroud, rolling member and a retainer in a plurality of being arranged between the raceway face of ring and outer shroud, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of this rolling member and the ratio between the pitch diameter are not more than 0.03, and this rolling bearing with ultra-thin-wall is characterized in that: described retainer is to be made by a kind of resin material, and the coefficient of linear expansion of this resin material is 1 to 2 with the ratio of the coefficient of linear expansion of Bearing Steel.

A kind of rolling bearing with ultra-thin-wall, it comprises in one rolling member and a retainer between the raceway face of ring and outer shroud in ring, outer shroud, a plurality of being arranged on, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of this rolling member and the ratio between the pitch diameter are not more than 0.03, and this rolling bearing with ultra-thin-wall is characterized in that: described retainer is to be not more than 0.5% resin material by a kind of water absorption rate to make.

The object of the invention to solve the technical problems also can be applied to the following technical measures to achieve further.

The coefficient of linear expansion of aforesaid resin material is 1 to 2 with the ratio of the coefficient of linear expansion of Bearing Steel.

Aforesaid rolling bearing with ultra-thin-wall is provided with a slit in the stylolitic part between the adjacent recess of wherein said retainer.

Aforesaid rolling bearing with ultra-thin-wall alternately is provided with a plurality of ball restriction recesses and the unrestricted recess of a plurality of ball on the wherein said retainer, the inlet diameter of described ball restriction recess is the 90-98% of ball diameter.

Aforesaid rolling bearing with ultra-thin-wall, wherein said retainer are a kind of crown retainers of ball guidance type, and this retainer is used for keeping ball by spherical recess, and has step-like cross-sectional structure.

Aforesaid rolling bearing with ultra-thin-wall, wherein said retainer should satisfy following condition: 0.4DB＜H＜0.6DB and h＜0.8H, and wherein DB is the diameter of ball, and H is the cross-sectional height of retainer, and h is the spacing of retainer stylolitic part.

The object of the invention to solve the technical problems also adopts following technological scheme to realize.A kind of rolling bearing according to the present invention's proposition with ultra-thin-wall, it comprises ring in, an outer shroud, rolling member and a retainer in a plurality of being arranged between the raceway face of ring and outer shroud, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of this rolling member and the ratio between the pitch diameter are not more than 0.03, and this rolling bearing with ultra-thin-wall is characterized in that: described retainer constitutes by a plurality of arcuate segments are connected into ring, and each segmentation all is provided with a plurality of recesses that are used to deposit ball, described retainer is a kind of crown retainer of ball guidance type that is used for keeping by spherical recess ball, and has step-like cross-sectional structure.

The object of the invention to solve the technical problems can also be further achieved by the following technical measures.Aforesaid rolling bearing with ultra-thin-wall, wherein said retainer should satisfy following condition: 0.4DB＜H＜0.6DB and h＜0.8H, and wherein DB is the diameter of ball, and H is the cross-sectional height of retainer, and h is the spacing of retainer stylolitic part.

The present invention compared with prior art has tangible advantage and beneficial effect.By above technological scheme as can be known, in order to reach aforementioned goal of the invention, major technique of the present invention thes contents are as follows:

According to one embodiment of present invention, the present invention proposes a kind of rolling bearing with ultra-thin-wall, it comprises: ring in, an outer shroud, rolling member and a retainer in a plurality of being arranged between the raceway of ring and outer shroud, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of rolling member and the ratio between the pitch diameter are not more than 0.03, and retainer is made by the resin material that can satisfy following one or two condition: (a), make its coefficient of linear expansion and the ratio of the coefficient of linear expansion of Bearing Steel be not less than 1, and be not more than 2; (b), making its water absorption rate is 0-0.5%.

Adopt above-mentioned this structure will make these segmentations be difficult to expand or shrink, so just can form the integral type retainer of an annular.Therefore, the performance of retainer is just very stable, but also can prevent or suppress the generation of abnormal sound.But, before this, because with the material of PA66 as retainer, therefore need to provide the part under this notconnect state always, so just can use the integral type retainer of annular by the material (its coefficient of linear expansion is very little with the ratio of the coefficient of linear expansion of steel, and is difficult to suction) of selecting to be difficult to expansion.Even action or delay-action situation in advance take place rolling member, also can make the property retention of retainer stable by saving this not connected part and retainer being manufactured annular.So just reduced in these segmentations rap sound or grating.

On the stylolitic part between the adjacent recess at retainer, a slit can be set.This slit makes stylolitic part be easy to take place resiliently deformable more, and like this, it is just less to insert the required power (the plug-in mounting power of ball) of ball.For example, owing to be provided with a plurality of slits, therefore just can make the ball plug-in mounting power in each recess be not more than 3kgf.

On retainer, can be arranged alternately ball restriction recess and ball does not have the constraint recess, and the inlet diameter of ball restriction recess is about the 90-98% of ball diameter.The feature of this superposition and above-mentioned slit has improved the plug-in mounting of ball.

This retainer can be a kind of crown retainer of ball guidance type that is used for being kept by spherical recess ball, and can have step-like cross-sectional structure.Even the retainer of this ball guiding makes the performance of retainer also can keep stable in advance or under the delay-action situation at ball, so just can prevent or suppress the grating that when retainer contacts with raceway, is produced.

This retainer can be a kind of retainer that satisfies following condition: 0.4DB＜H＜0.6DB and h＜0.8H, and wherein DB is the diameter of ball, and H is the cross-sectional height of retainer, and h is the spacing of the stylolitic part of retainer.

According to another embodiment of the present invention, the present invention also proposes a kind of ball bearing with ultra-thin-wall, it comprises: ring in, an outer shroud, rolling element and a retainer in a plurality of being arranged between the raceway face of ring and outer shroud, this retainer constitutes by along the circumferential direction a plurality of segmentations being connected into annular, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling element, the diameter of rolling element is not more than 0.03 with the ratio of pitch diameter, this rolling bearing with ultra-thin-wall is characterised in that: retainer is by being joined together to form a plurality of arcuate segments along annular, and each segmentation all is provided with a plurality of recesses that are used to deposit ball, this retainer is the crown retainer of a ball guidance type, it is used for keeping these balls by spherical recess, and has step-like cross-sectional structure.

And this retainer can be a kind of retainer that satisfies following condition: 0.4DB＜H＜0.6DB and h＜0.8H, and wherein DB is the diameter of ball, and H is the cross-sectional height of retainer, and h is the spacing of the stylolitic part of retainer.

Via as can be known above-mentioned, the invention relates to a kind of rolling bearing with ultra-thin-wall, structural design for a kind of annular integral type, it is by providing a kind of retainer of being made by resin material to be achieved, and this resin material should satisfy: condition (a) makes its coefficient of linear expansion and the ratio of the coefficient of linear expansion of Bearing Steel be not more than 2; Perhaps condition (b) makes its water absorption rate be not more than 0-0.5%; Or satisfy above-mentioned two conditions simultaneously, so just can be stable by the property retention that is used in the segmented retainer on the ultrathin wall rolling bearing, and can prevent the generation of abnormal sound.

By technique scheme, therefore the present invention just can reduce grating or other the unusual sound that is produced owing to make the performance of retainer can keep stable when retainer contacts with raceway.

In sum, the rolling bearing with ultra-thin-wall of special construction of the present invention can prevent from or stop under the situation of using the ultra-thin-wall rolling bearing to produce abnormal sound, thereby be suitable for practicality more.It has above-mentioned many advantages and use value, and in like product, do not see have similar structural design to publish or use and really genus innovation, no matter it structurally or bigger improvement all arranged on the function, have large improvement technically, and produced handy and practical effect, and more existing ultra-thin-wall rolling bearing has the multinomial effect of enhancement, thus be suitable for practicality more, and have the extensive value of industry, really be a new and innovative, progressive, practical new design.

Above-mentioned explanation only is the general introduction of technical solution of the present invention, for can clearer understanding technological means of the present invention, and can be implemented according to the content of specification, below with preferred embodiment of the present invention and conjunction with figs. describe in detail as after.

Description of drawings

Fig. 1 is an embodiment's of the rolling bearing of the present invention with ultra-thin-wall a structure sectional view.

Fig. 2 is the structure front elevation of a retainer.

Fig. 3 is a mating area partial plan view between the segmentation.

Fig. 4 is the plane outspread drawing of a plurality of segmentations.

Fig. 5 a is the enlarged diagram that the segmentation of slit is not set.

Fig. 5 b is the enlarged diagram that is provided with the segmentation of slit.

Fig. 6 is the sectional view of rolling bearing another embodiment of the present invention with ultra-thin-wall bearing.

Fig. 7 a is the plane outspread drawing of segmentation shown in Figure 6.

Fig. 7 b is the sectional view of segmentation shown in Figure 6.

Fig. 8 is the structure sectional view of a CT scan apparatus.

Fig. 9 is the structure sectional view that the retainer of ultrathin wall rolling bearing appears at the inconsistent phenomenon in the assembly area of segmentation.

Figure 10 is the front elevation that has traditional sectional type retainer now.

Embodiment

Below in conjunction with accompanying drawing and preferred embodiment, to its embodiment of the rolling bearing with ultra-thin-wall, structure, feature and the effect thereof that foundation the present invention proposes, describe in detail as after.

Seeing also shown in Figure 1ly, is a kind of cross sectional representation that is used on the CT scan equipment and has the rolling bearing 55 of ultra-thin-wall.The rolling bearing with ultra-thin-wall 55 of preferred embodiment of the present invention, it comprises: the outer shroud of an annular 1, one are arranged on the interior ring 2 of interior all sides of outer shroud 1, a plurality of rolling element or ball 3 (in this case with one heart, ball 3 rollably is arranged between the raceway face 2a of the raceway face 1a of outer shroud 1 and interior ring 2), one be used to make these balls 3 on circumference, to keep uniformly-spaced retainer 4 and Sealing 5a, the 5b of location, sealing

part

5a and 5b are used for the opening that is arranged on the bearing opposite end is sealed.

In the accompanying drawings, rolling element is expressed as ball 3, but also can adopt roller.And, only show one in the drawings and be provided with the single rolling bearing that single rolling element is a ball 3, but the present invention is not limited thereto, also can adopt double-row roller bearing with two row's rolling elements.

This bearing is a kind of rolling bearing with ultra-thin-wall, and its pitch diameter PCD is about 500 millimeters to 1500 millimeters, and the diameter DB of ball 3 and the ratio φ between the pitch diameter PCD are not more than 0.03; For example, if ball diameter is 1/2 inch (12.7mm), and pitch diameter PCD is 1041.4mm, and the ratio φ between the two just is 0.012 so.

An end face of outer shroud 1 is provided with a plurality of attachment holes 8, and unshowned secure component for example bolt can be screwed in these attachment holes 8, so just outer shroud 1 can be fixed on the rotary frame 57 of CT scan equipment (as shown in Figure 8).On interior ring 2, also be provided with a plurality of attachment holes 9, the secure component (not shown) resemble the bolt can be screwed in these attachment holes 9, thereby interior ring 2 is fixed on the fixed frame 56, as shown in Figure 8.So just as can be seen: outer shroud 1 has constituted one can be with the rotary component of rotary frame 57 rotations, and interior ring 2 has then constituted a non-rotatable fixed component.Difference according to the structure of CT scan equipment, also can be according to opposite mode, outer shroud 1 is arranged to be used as the structural type of non-rotatable fixed side, and interior ring 2 is arranged to be used as the structural type of the rotary side that can rotate with rotary frame 57.

Seeing also shown in Figure 2ly, is the structure front elevation of a retainer.This retainer 4 is a kind of sectional type retainers as shown in the figure, and on this retainer, a plurality of arcuate segments link together with annular form along its circumference.Each segmentation 40 is all made by a kind of resin material is carried out injection molding.As shown in Figure 3 and Figure 4, being separately positioned on convex on the opposite end of each segmentation 40 or

concavity mating part

44a or 44b is mounted to and is arranged in the concavity or convex

mating part

44b or 44a on the segment end portion that is complementary, so that it is bonded with each other along circumference, thereby adjacent segmentation 40 is linked together, form an annular retainer 4.In addition, Fig. 3 and Fig. 4 also show an arcuate segments that is launched into straight line shape.

See also Fig. 3, shown in Figure 4, with the segmentation shown in the example forms 40, it comprises among the figure: the bottom 41 of an arc, and this curved bottom 41 obtains by on a plurality of circumferential positions an annular element being divided into a plurality of parts; A plurality of from the bottom 41 stylolitic parts that stretch out vertically 42; And be arranged on

recess

43a, 43b between the adjacent stylolitic part 42.Two kinds of

recess

43a, 43b are arranged: the first recess 43a, it has function that keeps ball 3 and the function that ball 3 is spacedly distributed; The second recess 43b, it only has the function that ball 3 is spacedly distributed.See also shown in Fig. 5 (a), the notch width HW of each first recess 43a is less than the diameter DB (as shown in Figure 1) of ball 3, deviates from towards notched side to prevent ball 3, thereby ball 3 is remained in the first recess 43a.The notch width of the second recess 43b is greater than the diameter of ball 3, so that ball 3 can move freely vertically.Like this, the second recess 43b does not just have the maintenance function identical with the first recess 43a, but only has the ball of making 3 function that is spacedly distributed.Each segmentation 40 all is provided with two to three kinds along staggered recess 43a of circumference and recess 43b.

The purpose that two kinds of recesses (promptly having ball keeps the first recess 43a of function and do not have the second recess 43b that ball keeps function) are set is: make these be used to keep the recess of ball to be staggered arrangement, so that install.Particularly, make that DB is the diameter of ball 3, HW is the inlet diameter of ball 3, and it is suitable having the such relation of HW=0.90DB-0.98DB so.For ball restriction recess, if interfere excessively, the insertion of ball is just very difficult so; On the contrary, if amount of interference is too small, ball will drop out owing to chock (chock) or analog so.Therefore, amount of interference is set to one and not only had been convenient to insert ball, but also can prevents the best amount of interference that ball drops.In addition, if HW is excessive, the axial clearance of ball in retainer will be excessive so, and the angle that produces vibration and sound from operating process considers that this point is very unfavorable; Therefore the best is set to HW=0.90-0.94DW.

The operation that ball 3 is installed in recess 43a and the 43b is by the opening on recess 43a and the 43b ball 3 pushing tows to be realized in recess.At this moment, ball 3 need be pushed in the first recess 43a, make stylolitic part 42 expansions at inlet side simultaneously, and for the second recess 43b, just need not so bother, therefore just help rolling member 3 is installed in the retainer 4.In addition, the shape of above-mentioned

recess

43a and 43b and structure be only for illustrating for example, therefore can be according to the difference of the factors such as service condition of bearing, and adopt multiple different dimple shapes (for example single dimple shapes) and multiple recess structure.

The above-mentioned first and

second recess

43a, 43b all has a recess gap between the surface of ball 3 and the internal surface of recess (concave surface) 47, and the existence in this recess gap makes retainer 4 radially to move in the rotary course of bearing.Retainer 4 can contact with the outer surface 2b of interior ring 2 by this motion, or contacts with the interior perimeter surface 1b of outer shroud 1, rotates (as shown in Figure 1) with regard to bootable retainer 4 like this.In the embodiment shown in fig. 1, show the retainer 4 of outer shroud guidance type with example, this structure is that the mode that the inner periphery 1b of outer periphery 45 and outer shroud 1 by making retainer 4 is in contact with one another guides retainer 4 rotations.In the parts of this outer shroud guidance type, bearing is designed to make the inner periphery 46 of retainer and the not contacted structural type of outer periphery 2b of interior ring 2.

See also shown in Figure 10ly, in prior art as shown in figure 10, by the large-size rolling bearing support that a plurality of arcuate segments constitute, a circumferential position is provided with not connected clearance G.The purpose that this clearance G is set is to adjust the girth of support, and the meeting of the girth of support is expanded owing to the variation of temperature and water absorption rate and shunk.Therefore, if make each segmentation that constitutes support, so just can adopt the annular integral structure of (not connected part) very close to each other with a kind of material that is difficult to expand or shrinks.

Like this, as shown in table 1 to the result of study of various resin materials.In this table 1, because the expansion of right side stylolitic part and contraction and the interference that produces with raceway is consistent with the result that the ultra-thin-wall bearing series product that utilizes NTN company to produce obtains.For example, if the pitch diameter of bearing is 1000 millimeters, the diameter of the guiding clearance between outer shroud and retainer is 1 millimeter, retainer is made by PA66 (nylon 66), and the hypothesis environment temperature changes to 60 ℃ from 20 ℃, and the water absorption rate of retainer changes under 3% the condition from 2%, so when the guiding clearance be-2.3 millimeters, and during the influence factor below considering, this support will interfere with raceway.

Influence of temperature variation=(4.5-1.25) * 10 ^-5* 100 * Δ T (60-20)=1.3 millimeter.

Influence=0.1% that support produces because of expansion when suction (this value is exactly the percentage of its dimensional changes when water absorption rate increases by 1%) * 1000=1 millimeter is (if this value is not more than 5 millimeters, ball just is under the steady-working state so, so just can not have noise problem).

Table 1

Result of study to resin material

Material	Coefficient of linear expansion (/ ℃) * 10 ^-5	The ratio of coefficient of linear expansion	Water absorption rate (%)	Owing to expand with shrink and interfere with raceway
Material	Coefficient of linear expansion (/ ℃) * 10 ^-5	The ratio of coefficient of linear expansion	Water absorption rate (%)	Owing to expand with shrink and interfere with raceway	Bearing Steel	1.25	1		-
PI (polyimide)	1.5	1.2	0.2	Do not have	Bearing Steel	1.25	1		-
PI (polyimide)	1.5	1.2	0.2	Do not have	PPS (polyphenylene sulfide)	2.2	1.76	(0.02 not suction)	Do not have
PA46 (nylon 46)	3.0	2.4	3.0	Have	PPS (polyphenylene sulfide)	2.2	1.76	(0.02 not suction)	Do not have
PA46 (nylon 46)	3.0	2.4	3.0	Have	PA66 (nylon 66)	3-6 mean value: 4.5	3.6	2.2	Have

From these results of study as can be seen: those materials that can be used as the material that is difficult to expand or shrinks satisfy following condition:

(a), the ratio of coefficient of linear expansion (resin/Bearing Steel) is not more than 2.

(b), water absorption rate is not more than 0.5%.

Because use resembles the such material of PPS (polyphenylene sulfide) and can improve rigidity (Young's modulus), ball therefore just may occur situation of difficult is installed; Therefore, preferably improve installability.For example, because the resiliently deformable that slit helps stylolitic part 2 is being set, therefore just can improve installation on the stylolitic part between the adjacent recess 2.Have been found that: the required power of plug-in mounting ball is not more than 3kgf in each recess.Table 2 shows the test result of ball plug-in mounting.

Table 2

The plug-in mounting test result of ball

To be illustrated Fig. 6 and embodiment shown in Figure 7 below.In addition, Fig. 6 a shows an existing traditional retainer, to be used for contrast.In the present embodiment, retainer 4 is used as the guiding element of ball 3, no matter ball 3 moves or hysteresis motion in advance like this, it is stable that the performance of retainer 4 can both keep, thereby can prevent to produce when retainer 4 and raceway 1 or 2 are in contact with one another grating.

See also Fig. 6, shown in Figure 7, as we know from the figure: in the present embodiment, adopted a kind of crown retainer that is provided with spherical recess 43c.This crown retainer is a kind of retainer that has the horn shape part, and the shape of this horn shape part allows itself and rolling element and retainer to combine, and can be by from a side it being pushed the assembly manipulation of finishing retainer in the bearing.In addition, it still is a kind of sectional type retainer.

In addition, compare with the existing traditional retainer shown in Fig. 6 a, in the embodiment shown in Fig. 6 b, the cross-sectional height H of retainer adopts maximum value, this maximum value makes it can be along axial plug-in mounting retainer 4, and the cross-sectional height h of retainer stylolitic part is decided by the quantity of material that is eliminated, and this quantity is with consistent at the jump of the relative retainer cross-sectional height H shown in jump 49 places.Because retainer 4 has a recess gap, therefore will in retainer 4, form a radial clearance by relative ball 3.The leading role of ball is by jump 49 is produced greater than the mode of radial clearance.Set the relation between numerical value H and the h for can satisfy following relation degree, just can form a kind of retainer of ball guiding.

0.4DB<H<0.6DB

h<0.8H

Adopt this crown retainer that has step shape cross-sectional structure and have a spherical recess just can form the ball leading role, even ball 3 shifts to an earlier date or hysteresis motion like this, the stable performance of retainer 4 is got off, and can solve because of retainer contacts with raceway 1 or 2 and produce the problem of grating.Therefore, in this embodiment, we believe: retainer 4 is not absolute integral structure for annular; It also can have not connected part G (as shown in figure 10).

In the superincumbent explanation, as shown in Figure 1, contacting and guided between the outer periphery 45 that the retainer 4 of an outer shroud guidance type is adapted to pass through retainer and the inner periphery 1b of outer shroud rotates; But the present invention is not limited thereto.In the present invention can be applicable to equally on the retainer of ring guidance type, contacting and guided between the inner periphery 46 that this retainer is adapted to pass through retainer and the outer periphery 2b of interior ring, thus retainer 4 is rotated; The present invention also can be applicable on the retainer of rolling element guidance type, and this retainer only is suitable for by being guided with contacting of rolling element 3, thereby rotates.

According to the present invention,, therefore just can reduce grating or other the unusual sound that when retainer contacts with raceway, is produced because the performance of retainer can keep stable.

The above, it only is preferred embodiment of the present invention, be not that the present invention is done any pro forma restriction, though the present invention discloses as above with preferred embodiment, yet be not in order to limit the present invention, any those skilled in the art, in not breaking away from the technical solution of the present invention scope, when the technology contents that can utilize above-mentioned announcement is made a little change or is modified to the equivalent embodiment of equivalent variations, in every case be the content that does not break away from technical solution of the present invention, according to technical spirit of the present invention to any simple modification that above embodiment did, equivalent variations and modification all still belong in the scope of technical solution of the present invention.

Claims

1. rolling bearing with ultra-thin-wall, it comprises in one rolling member and a retainer between the raceway face of ring and outer shroud in ring, outer shroud, a plurality of being arranged on, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of this rolling member and the ratio between the pitch diameter are not more than 0.03, and this rolling bearing with ultra-thin-wall is characterized in that:

Described retainer is to be made by a kind of resin material, and the coefficient of linear expansion of this resin material is 1 to 2 with the ratio of the coefficient of linear expansion of Bearing Steel.

2. rolling bearing with ultra-thin-wall, it comprises in one rolling member and a retainer between the raceway face of ring and outer shroud in ring, outer shroud, a plurality of being arranged on, this retainer forms by a plurality of segmentations are connected into annular along circumference, and each segmentation all is provided with a plurality of recesses that are used to deposit rolling member, the diameter of this rolling member and the ratio between the pitch diameter are not more than 0.03, and this rolling bearing with ultra-thin-wall is characterized in that:

Described retainer is to be not more than 0.5% resin material by a kind of water absorption rate to make.

3. the rolling bearing with ultra-thin-wall according to claim 2, the coefficient of linear expansion that it is characterized in that described resin material is 1 to 2 with the ratio of the coefficient of linear expansion of Bearing Steel.

4. according to claim 1,2 or 3 described rolling bearings, it is characterized in that being provided with a slit in the stylolitic part between the adjacent recess of wherein said retainer with ultra-thin-wall.

5. according to claim 1,2 or 3 described rolling bearings with ultra-thin-wall, it is characterized in that alternately being provided with on the wherein said retainer a plurality of ball restriction recesses and the unrestricted recess of a plurality of ball, the inlet diameter of described ball restriction recess is the 90-98% of ball diameter.

6. according to claim 1,2 or 3 described rolling bearings with ultra-thin-wall, it is characterized in that wherein said retainer is a kind of crown retainer of ball guidance type, this retainer is used for keeping ball by spherical recess, and has step-like cross-sectional structure.

7. the rolling bearing with ultra-thin-wall according to claim 6, it is characterized in that wherein said retainer satisfies following condition: 0.4DB＜H＜0.6DB and h＜0.8H, wherein DB is the diameter of ball, H is the maximum value of the cross-sectional height of retainer, and h is the cross-sectional height of retainer stylolitic part.