JPH0673444U

JPH0673444U - Rolling bearing

Info

Publication number: JPH0673444U
Application number: JP1525893U
Authority: JP
Inventors: 梅光小林
Original assignee: NTN Corp
Current assignee: NTN Corp
Priority date: 1993-03-30
Filing date: 1993-03-30
Publication date: 1994-10-18

Abstract

(57)【要約】【目的】転動体の保持器を外輪で案内する軸受の耐久
性を向上させる。【構成】転動体の保持器４を案内する外輪１の内周面
６に、独立した微小な凹形状のくぼみを無数にランダム
に形成し、表面の面粗さを、パラメータＳＫ値が軸方向
及び円周方向の何れもマイナスとなり、しかも微小くぼ
みの占める表面積比率が１０〜４０％となるようにし、
外輪１の内周面の油膜形成率を向上させ、外輪１と保持
器４の接触面の焼付き発生を防ぎ、長寿命化を図る。 (57) [Abstract] [Purpose] To improve the durability of the bearing that guides the cage of rolling elements by the outer ring. [Structure] An infinite number of independent minute concave recesses are randomly formed on the inner peripheral surface 6 of the outer ring 1 for guiding the cage 4 of the rolling element, and the surface roughness of the surface is determined by the parameter SK value in the axial direction. And the circumferential direction are both negative, and the surface area ratio occupied by the microscopic depressions is 10 to 40%.
The oil film formation rate on the inner peripheral surface of the outer ring 1 is improved, the occurrence of seizure on the contact surface between the outer ring 1 and the cage 4 is prevented, and the service life is extended.

Description

【考案の詳細な説明】[Detailed description of the device]

【０００１】[0001]

【産業上の利用分野】[Industrial applications]

この考案は、転動体の保持器を外輪の内周面で案内する形式のころがり軸受、更に詳しくは、外輪と保持器の接触間の潤滑性を良くして長寿命を示すころがり軸受に関する。 The present invention relates to a rolling bearing of a type in which a cage of rolling elements is guided by an inner peripheral surface of an outer ring, and more specifically, to a rolling bearing having a long life by improving lubricity between the contact between the outer ring and the cage.

【０００２】[0002]

【従来の技術】[Prior art]

図１のように、保持器を外輪で案内する形式のころがり軸受は、外輪１と内輪２の間に介在させた多数の転動体３を保持器４で一定の間隔に保持し、保持器４の外周面５が外輪１の内周面６に接近した構造になっている。 As shown in FIG. 1, in a rolling bearing of a type in which a cage is guided by an outer ring, a large number of rolling elements 3 interposed between an outer ring 1 and an inner ring 2 are held by a cage 4 at regular intervals, and The outer peripheral surface 5 is close to the inner peripheral surface 6 of the outer ring 1.

【０００３】上記のようなころがり軸受は、外輪１の内周面６と保持器４の外周面５があるところで接触して回転することになると共に、軸受を高速回転で使用する場合、内輪２の回転のとき、潤滑油は遠心力により外側に飛ばされ、外輪１の内周面６及び外輪溝７に当たり、保持器４の外周面との潤滑及び転動体３との潤滑として作用する。The rolling bearing as described above comes into contact with and rotates when the inner peripheral surface 6 of the outer ring 1 and the outer peripheral surface 5 of the cage 4 are present, and when the bearing is used at high speed, the inner ring 2 At the time of rotation, the lubricating oil is spattered outward by centrifugal force, hits the inner peripheral surface 6 of the outer ring 1 and the outer ring groove 7, and acts as lubrication with the outer peripheral surface of the cage 4 and lubrication with the rolling elements 3.

【０００４】ところで、従来のころがり軸受における外輪１の内周面６及び保持器４の外周面５は、それほど面粗さを小さくしていないと共に、加工方法によって、研削や旋削面は周方向に沿うようになっていた。By the way, in the conventional rolling bearing, the inner peripheral surface 6 of the outer ring 1 and the outer peripheral surface 5 of the retainer 4 are not so small in surface roughness, and the grinding or turning surface is circumferentially changed depending on the processing method. It was supposed to follow.

【０００５】[0005]

【考案が解決しようとする課題】[Problems to be solved by the device]

上記のような従来の面条件では、潤滑油が外輪１の内周面６に対して周方向に流れやすく、このため、保持器４との接触面に油膜を形成しにくく、外輪１及び保持器４の接触面に焼付きが起り、ころがり軸受の寿命を低下させるという問題がある。 Under the conventional surface conditions as described above, the lubricating oil is likely to flow in the circumferential direction with respect to the inner peripheral surface 6 of the outer ring 1, so that it is difficult to form an oil film on the contact surface with the cage 4, and the outer ring 1 and the holding surface There is a problem that seizure occurs on the contact surface of the container 4 and the life of the rolling bearing is shortened.

【０００６】そこでこの考案は、外輪の内周面に、油膜の形成に優れた表面状態を与え、外輪と保持器の潤滑を良くすることによって焼付の発生を防ぐことができるころがり軸受を提供することを課題としている。In view of this, the present invention provides a rolling bearing that can prevent seizure by providing the inner surface of the outer ring with a surface condition excellent in forming an oil film and improving the lubrication of the outer ring and the cage. The challenge is to provide.

【０００７】[0007]

【課題を解決するための手段】[Means for Solving the Problems]

上記のような課題を解決するため、この考案は、外輪の保持器案内面に、微小な凹形状のくぼみを無数にランダムに形成し、この面の面粗さを、面粗さのパラメータＳＫ値が軸方向及び円周方向の何れもマイナスとなるようにし、前記微小くぼみの占める表面積比率が１０〜４０％となるようにした構成を採用したものである。 In order to solve the above-mentioned problems, the present invention forms an infinite number of minute concave depressions on the cage guide surface of the outer ring at random, and determines the surface roughness of this surface as a parameter of the surface roughness. The SK value is set to be negative in both the axial direction and the circumferential direction, and the surface area ratio occupied by the minute recesses is set to 10 to 40%.

【０００８】[0008]

【作用】[Action]

外輪の保持器案内面に微小な凹形状のくぼみを無数にランダムに形成したので、くぼみが油溜りとなり、保持器案内面の油膜形成率が向上し、外輪と保持器の接触面の焼付発生を防止する。 Innumerable minute concave dents are randomly formed on the cage guide surface of the outer ring, so that the cavities become oil reservoirs and the rate of oil film formation on the cage guide surface improves, and seizure occurs on the contact surface between the outer ring and cage. Prevent.

【０００９】[0009]

【実施例】【Example】

以下、この考案の実施例を添付図面に基づいて説明する。 An embodiment of the present invention will be described below with reference to the accompanying drawings.

【００１０】ころがり軸受は図１で示したように、転動体３の保持器４を外輪１で案内する形式であり、この外輪１の保持器案内面である内周面６が、図２のように、微小な凹形状のくぼみ８を無数にランダムに形成した微小粗面になっている。As shown in FIG. 1, the rolling bearing is of a type in which the cage 4 of the rolling element 3 is guided by the outer ring 1, and the inner peripheral surface 6 which is the cage guide surface of the outer ring 1 is shown in FIG. As described above, a minute rough surface is formed by forming innumerable minute concave recesses 8 innumerably.

【００１１】この微小粗面は、面粗さを外表面の軸方向と円周方向のそれぞれを求めてパラメータＲＭＳで表示したとき、軸方向面粗さＲＭＳ（Ｌ）と円周方向面粗さＲＭＳ（Ｃ）の比ＲＭＳ（Ｌ）／ＲＭＳ（Ｃ）を平均値１．０以下にすると共に、表面粗さのパラメータＳＫ値が軸方向、円周方向の何れもマイナスで、平均値−１．５以下になり、更に上記微小粗面の微小なくぼみの平均面積は、等価円直径３ μｍφ以下を除いて整理したとき５０〜２５０μｍ²、くぼみの表面積比率は１０〜４０％、くぼみの最大面積は１５０００μｍ²である。The micro-rough surface has a surface roughness RMS (L) and a circumferential surface roughness RMS (L) when the surface roughness is obtained by calculating the axial direction and the circumferential direction of the outer surface and displaying them with the parameter RMS. The ratio RMS (L) / RMS (C) of the RM S (C) is set to an average value of 1.0 or less, and the surface roughness parameter SK value is negative in both the axial direction and the circumferential direction, and the average value. Value -1. The average area of the micro recesses of the micro rough surface is 50 to 250 μm ² when arranged excluding the equivalent circular diameter of 3 μmφ or less, the surface area ratio of the recesses is 10 to 40%, and the maximum recesses are The area is 15000 μm ² .

【００１２】上記のような表面の粗面条件を得るための表面加工処理は、特殊なバレル研磨によって、所望する仕上面を得ることができる。In the surface processing treatment for obtaining the above-mentioned rough surface condition, a desired finished surface can be obtained by special barrel polishing.

【００１３】前記パラメータＳＫ値とは、表面粗さの分布曲線の歪み度（ＳＫＥＷＮＥＳＳ）を指し、ガウス分布のような対称形分布はＳＫ値が０となるが、パラメータＳＫ値を円周方向、軸方向とも平均値−１．５以下とした設定値は、表面凹部の形状、分布が加工条件により油膜形成に有利な範囲である。The parameter SK value refers to the degree of distortion (SKEWNESS) of the distribution curve of the surface roughness, and a symmetric distribution such as a Gaussian distribution has an SK value of 0, but the parameter SK value is the circumferential direction. In the axial direction, the set value with the average value of −1.5 or less is a range in which the shape and distribution of the surface recesses are advantageous for forming an oil film depending on the processing conditions.

【００１４】上記した外輪１の内周面６は、油膜の形成能力に優れ、十分な油膜厚さを確保し、保持器４の接触部の金属接触を極力抑えることによって、外輪１と保持器４の接触による焼付発生を防止することになる。The inner peripheral surface 6 of the outer ring 1 described above is excellent in the ability to form an oil film, ensures a sufficient oil film thickness, and suppresses metal contact at the contact portion of the cage 4 as much as possible. The occurrence of seizure due to the contact of No. 4 will be prevented.

【００１５】図３は外輪１の内周面６に施した微小粗面加工の仕上面状況を示し、この微小粗面のくぼみの定量的測定を行なうには、外輪１の内周面を拡大し、その画像から市販されている画像解析システムにより定量化できる。FIG. 3 shows the state of the finished surface of the micro-roughening process applied to the inner peripheral surface 6 of the outer ring 1, and the inner peripheral surface of the outer ring 1 is enlarged in order to quantitatively measure the depressions of the micro-rough surface. However, the image can be quantified by a commercially available image analysis system.

【００１６】画像の白い部分は表面平坦部、微小なくぼみは黒い部分として解析する。例えば（株）ピアスのＬＡ−５２５画像解析システムを用いて解析すると、先ず原画の濃淡を強調フィルターで明確化し、その後非常に微細な黒い部分である等価円直径３μｍφ以下はノイズイレーサーで除去する。The white portion of the image is analyzed as a flat surface portion, and the minute depression is analyzed as a black portion. For example, when analyzed using the LA-525 image analysis system of Pierce Co., Ltd., first the density of the original image is clarified with an emphasis filter, and then the very fine black portion of the equivalent circle diameter of 3 μmφ or less is removed with a noise eraser. .

【００１７】ノイズイレーサーで除去した後に残された微小なくぼみの大きさ、分布、微小なくぼみの表面積比率を求め、外輪内周面を評価するものである。The size, distribution, and surface area ratio of the micro recesses left after the removal with the noise eraser are obtained, and the inner peripheral surface of the outer ring is evaluated.

【００１８】次に、外輪１の内周面６の油膜形成率の向上を確認するため、針状ころ軸受のころ転動体の表面に、微小なくぼみの面積比率、くぼみの平均面積、平均等価直径等の異なる状況を与え、ラジアル荷重による耐久寿命試験を行なった結果について説明する。Next, in order to confirm the improvement of the oil film formation rate on the inner peripheral surface 6 of the outer ring 1, on the surface of the roller rolling element of the needle roller bearing, the area ratio of the minute depressions, the average area of the depressions, and the average equivalent are formed. The results of the durability life test under radial load under different conditions such as diameter will be explained.

【００１９】寿命試験に用いたニードル軸受は、図４に示すように、外径Ｄｒ＝３８mm、内径ｄｒ＝２８mm、転動体３ａの直径Ｄ＝５mm、長さＬ＝１３mmで、１４本の転動体を用いた保持器４ａ付の軸受である。As shown in FIG. 4, the needle bearing used in the life test has an outer diameter Dr = 38 mm, an inner diameter dr = 28 mm, a diameter D = 5 mm of the rolling element 3a, and a length L = 13 mm. This is a bearing with a cage 4a using rolling elements.

【００２０】また、使用した試験装置は、図５に概略図で示したようなラジアル荷重試験機１１を使用し、回転軸１２の両側に試験軸受１３を取付け、回転と荷重を与えて試験を行なうものである。The test equipment used is a radial load tester 11 as shown in the schematic view of FIG. 5, test bearings 13 are attached to both sides of a rotary shaft 12, and rotation and load are applied to carry out the test. It is something to do.

【００２１】試験に用いたインナーレース（相手軸）の仕上は研削仕上のＲｍａｘ０．４〜４μｍである。アウターレース（外輪）は研削仕上Ｒｍａｘ１．６μｍで何れの場合も共通である。The finish of the inner race (opposite shaft) used in the test is Rmax 0.4 to 4 μm for the grinding finish. The outer race (outer ring) has a grinding finish Rmax of 1.6 μm and is common in all cases.

【００２２】また、試験条件は以下の通りである。The test conditions are as follows.

【００２３】軸受ラジアル荷重１４６５ｋｇｆ回転数３０５０ｒｐｍ潤滑剤タービン油図６（Ａ）は微小なくぼみの面積比率と耐久寿命の結果を、また図６（Ｂ）は微小なくぼみの平均面積と耐久寿命の結果を示している。Bearing radial load 1465 kgf Rotational speed 3050 rpm Lubricant Turbine oil FIG. 6A shows the result of the area ratio of the micro recesses and the durable life, and FIG. 6B shows the average area of the micro recesses and the durability life. The results are shown.

【００２４】図６（Ａ）と図６（Ｂ）の結果より、耐久寿命は面積比率で１０％以上、平均面積で３５μｍ²以上のものが、計算寿命に対する耐久寿命（Ｌ₁₀）の比率で４以上となり、耐久寿命に効果がある。From the results of FIG. 6 (A) and FIG. 6 (B), the durable life is 10% or more in area ratio and 35 μm ² or more in average area is the ratio of the durable life (L ₁₀ ) to the calculated life. 4 or more, which is effective for the durable life.

【００２５】上記の耐久寿命試験は針状ころ軸受の転動体表面に微小なくぼみを設けておこなったが、ころがり軸受における外輪の内周面に微小なくぼみを設けても、前記試験結果と同様の耐久性の向上効果が認められる。The above-mentioned durability life test was carried out by providing a minute recess on the surface of the rolling element of the needle roller bearing, but even if a minute recess is provided on the inner peripheral surface of the outer ring of the rolling bearing, A similar effect of improving durability is recognized.

【００２６】なお、微小なくぼみの面積比率が４０％以上、平均面積２５０μｍ²以上は、接触有効長さが減少し、長寿命の効果は減少する傾向にある。When the area ratio of the micro recesses is 40% or more and the average area is 250 μm ² or more, the effective contact length tends to decrease and the effect of long life tends to decrease.

【００２７】[0027]

【考案の効果】[Effect of device]

以上のように、この考案によると、外輪の保持器案内面をランダムな微小粗面に形成し、この微小なくぼみの占める表面積比率を１０〜４０％にしたので、保持器案内面の油膜形成に有利となり、外輪と保持器の接触部分に焼付きの発生がなく、ころがり軸受の長寿命化を図ることができる。 As described above, according to the present invention, the cage guide surface of the outer ring is formed into a random minute rough surface, and the surface area ratio occupied by the minute recesses is set to 10 to 40%. Therefore, the oil film on the cage guide surface is formed. This is advantageous for forming, the seizure does not occur in the contact portion between the outer ring and the cage, and the life of the rolling bearing can be extended.

【図面の簡単な説明】[Brief description of drawings]

【図１】ころがり軸受の縦断面図[Fig.1] Longitudinal section of rolling bearing

【図２】この考案のころがり軸受における外輪と保持器
の接触部を拡大した縦断面図FIG. 2 is an enlarged vertical sectional view of a contact portion between an outer ring and a cage in the rolling bearing of the present invention.

【図３】外輪の内周面の仕上面状況を示す概略図FIG. 3 is a schematic view showing a finished surface condition of an inner peripheral surface of an outer ring.

【図４】寿命試験に用いたニードル軸受の断面図FIG. 4 is a cross-sectional view of the needle bearing used in the life test.

【図５】試験装置の概略図FIG. 5 is a schematic diagram of a test apparatus.

【図６】（Ａ）と（Ｂ）は寿命試験の結果を示すグラフ6A and 6B are graphs showing the results of a life test.

【符号の説明】[Explanation of symbols]

１外輪２内輪３転動体４保持器６内周面８くぼみ 1 Outer ring 2 Inner ring 3 Rolling element 4 Cage 6 Inner peripheral surface 8 Cavity

Claims

【実用新案登録請求の範囲】[Scope of utility model registration request]

【請求項１】転動体の保持器を外輪で案内する形式の
ころがり軸受において、外輪の保持器案内面に、微小な
凹形状のくぼみを無数にランダムに形成し、この面の面
粗さを、面粗さのパラメータＳＫ値が軸方向及び円周方
向の何れもマイナスとなるようにし、前記微小くぼみの
占める表面積比率が１０〜４０％となるようにしたこと
を特徴とするころがり軸受。1. In a rolling bearing of the type in which a cage of rolling elements is guided by an outer ring, countless minute concave recesses are randomly formed on the cage guide surface of the outer ring, and the surface roughness of this surface is determined. The rolling bearing is characterized in that the surface roughness parameter SK value is set to be negative in both the axial direction and the circumferential direction, and the surface area ratio occupied by the minute recesses is 10 to 40%.