Structures of Needle Roller Cages for General Usage

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Shauna Young
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rollers. When combined with shafts and housin bores that are heat treated and accurately round as raceway surfaces, eedle Roller aes for General Usae are particularly useful in small spaces.

1 Structure and Features eedle Roller aes for General Usae are bearins which display excellent performance. eedle rollers with extremely small dimensional variations in diameter are incorporated and retained in their specially shaped caes with hih riidity and accuracy, which precisely uide the needle rollers. When combined with shafts and housin bores that are heat treated and accurately round as raceway surfaces, eedle Roller aes for General Usae are particularly useful in small spaces. In addition, since they are lihtweiht and have hih riidity as well as a lare lubricant holdin capacity, they can withstand severe operatin conditions such as hih speed rotation and shock loads, and they are used in a wide rane of applications. Structures of eedle Roller aes for General Usae ae eedle roller ae eedle roller 1 1

2 Types Accuracy Specifications of shaft and housin eedle Roller aes for General Usae are available in two types, with sinle row needle rollers and double row needle rollers. For applications such as crank shafts where these bearins are difficult to install, it is also possible to make split type bearins. If such bearins are required, please contact. For eedle Roller aes for Enine onnectin Rods ( and V ), see pae 4. Identification umber The identification number of eedle Roller aes for General Usae consists of a model code, dimensions and any supplemental codes. The arranement examples are shown below. The diameter tolerances of needle rollers of eedle Roller aes for General Usae are classified by classification symbols shown in Table 1. If a classification symbol is not indicated in an identification number, the classification symbol "" is applied. When two or more bearins are used in tandem arranement on the same shaft, it is necessary to select bearins of the same classification symbol to obtain an even load distribution. The tolerance of the cae width B c is Table 1 Diameter tolerances of needle rollers lassification symbol B unit: m Tolerance of mean value of needle roller diameter For the raceways, a surface hardness of 5 4HR and a surface rouhness 0.2 mr a or less are desirable. However, when the operatin conditions are not severe, a surface rouhness 0. mr a or less can be used. When the surface hardness is low, it is necessary to correct the by the hardness factor specified on pae. Operatin temperature rane For synthetic resin caes, "" is added at the end of the identification number. The operatin temperature rane for eedle Roller aes for General Usae is +1. However, the maximum allowable temperature for synthetic resin caes is +1, and when they are continuously operated, it is +0. Fi.1 Fi.2 Examples of identification number Example 1 Type of bearin ae width Model code Roller set bore diameter Roller set outside diameter Tolerance of mean value of roller (Refer to Table 1.) Dimensions Supplemental code B 4 B B B Fit Radial clearances of eedle Roller aes for General Usae are determined by the dimensional accuracy of the raceways and needle rollers. Table 2 shows the recoended fits for the operatin conditions. Table 2 Recoended fits of shaft to the housin bore diameter G Tolerance class of shaft Operatin conditions F w F w Mountin The dimensions related to mountin of eedle Roller aes for General Usae are shown in Fis. 1 and 2. When mountin eedle Roller aes for General Usae, they are axially positioned by usin, for example, ir-clips for shaft and housin bore (WR and AR on pae ) as shown in Fis., 4 and 5. For hih speed applications, a heat treated and round spacer is positioned between the cae and the cir-clip as shown in Fi. 5 so that the cae does not make direct contact with the cir-clip. In this case, the cir-clip is normally mounted on the nonrotatin side. Fi. shows a mountin example in the case of outer rin rotation, and Fis. 4 and 5 show examples in the case of inner rin rotation. Fi. Example 2 Model code Dimensions Supplemental code W 4 B4 When hih operatin accuracy is required. When shock loads and oscillatin motions are applied. For eneral use When the temperature is hih, or mountin errors are lare. j5 h5 h5 5 f Fi.4 Type of bearin Roller set bore diameter Remark When settin the required radial clearance accordin to the operatin conditions, the clearance can easily be obtained by selectin and matchin the tolerances of needle rollers, shaft and housin bore. When variation of the clearance does not create any problems, h and G are used for shaft and housin bore, respectively. Roller set outside diameter ae width 4 Fi.5 Tolerance of mean value of roller (Refer to Table 1.) 1 1=0.2kf=0.4lbs. 1=0.0inch 1

3 EEDLE ROLLER AGES FOR GEERAL USAGE ote( 1 ) Remark speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. For synthetic resin caes, "" is added at the end of the identification number. 2 1=0.2kf=0.4lbs. 1=0.0inch

4 EEDLE ROLLER AGES FOR GEERAL USAGE ote( 1 ) speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. 4 1=0.2kf=0.4lbs. 1=0.0inch 5

5 EEDLE ROLLER AGES FOR GEERAL USAGE W 0 0 W W 1. W W W ote( 1 ) speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. 1=0.2kf=0.4lbs. 1=0.0inch

6 EEDLE ROLLER AGES FOR GEERAL USAGE W W ote( 1 ) speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. 1=0.2kf=0.4lbs. 1=0.0inch

7 EEDLE ROLLER AGES FOR GEERAL USAGE 52 W W ote( 1 ) speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. 1 1=0.2kf=0.4lbs. 1=0.0inch 1

EEDLE ROLLER AGES FOR GEERAL USAGE 0 5 1 5 54 5.5.5 52 52.5 1 44.5 54.5.5.5 4 1 5 5 5 1 4 5 2 0 0 0 0 0 4 00 0 0 00 00 4 0 52 0 00 0 00 0 4 00 0 0 0 2 0 1 0 1 00 5 0 5 000 2 000 000 000 000 000 000 000 0 0 0 0 0 0 0 1.

8 EEDLE ROLLER AGES FOR GEERAL USAGE ote( 1 ) speed applies to oil lubrication. For rease lubrication, a maximum of % of this value is allowable. 2 1=0.2kf=0.4lbs. 1=0.0inch

eedle Roller aes for Bi End eedle Roller aes for Small End Structure and Features eedle Roller aes for Enine onnectin Rods are bearins for use in enine connectin rods.

marines, snow mobiles, hih-speed compressors, etc. and also in eneral-purpose enines.

9 eedle Roller aes for Bi End eedle Roller aes for Small End Structure and Features eedle Roller aes for Enine onnectin Rods are bearins for use in enine connectin rods. These bearins have superior performance proven in hih performance enines of racin motor cycles, and are widely used in small motor vehicles, motor cycles, outboard marines, snow mobiles, hih-speed compressors, etc. and also in eneral-purpose enines. Bearins for enine connectin rods are used under extremely severe and complex operatin conditions such as heavy shock loads, hih speeds, hih temperatures and strinent lubrication. eedle Roller aes for Enine onnectin Rods are lihtweiht, and have hih s and hih riidity as well as superior wear resistance to withstand these severe conditions. Structures of eedle Roller aes for Enine onnectin Rods ae eedle roller Types In eedle Roller aes for Enine onnectin Rods, the types shown in Table 1 are available. ae Table 1 Types Type For bi end For small end Model code V eedle roller 4 5

eedle Roller aes for Bi End These roller caes are subjected to acceleration and deceleration durin their rotatin and epicyclic motion due to crank shaft rotation.

For the purpose of usin them under severe conditions such as hih speed and strinent lubrication, bearins plated with non-ferrous metals are also available on request.

10 eedle Roller aes for Bi End These roller caes are subjected to acceleration and deceleration durin their rotatin and epicyclic motion due to crank shaft rotation. To withstand such conditions, they are made of a special alloy and are lihtweiht with hih riidity. They are uided on their outer periphery surface with superior lubricatin properties. For the purpose of usin them under severe conditions such as hih speed and strinent lubrication, bearins plated with non-ferrous metals are also available on request. Hih-load capacity and hih-riidity caes to be used for racin motor cycles (See the photo bellow.), split needle caes for solid (one-piece) type crank-shafts and other special specification caes of various types are also available. Please consult when required. Hih-load capacity and hih-riidity cae Z eedle Roller aes for Small End V These roller caes oscillates at hih speeds within a limited loadin zone under heavy shock loads. Thus, these caes are desined to be lihtweiht and have hih riidity with a well-balanced structure. In these caes, a number of needle rollers havin a small diameter are incorporated to reduce the rollin contact stress in the loadin zone. eedle Roller aes for Small End are classified into two types, the outer surface uide type and the inner surface uide type. This classification is shown in the table of dimensions. In the outer surface uide type, the cae is uided by the slidin contact between the inner surface of the connectin rod and the outer surface of the cae. In the inner surface uide type, the cae is uided by the slidin contact between the outer surface of the pin and the inner surface of the cae. Identification umber The identification number of eedle Roller aes for Enine onnectin Rods consists of a model code, dimensions and any supplemental codes as shown below. Examples of identification number Accuracy The diameter tolerances of needle rollers of eedle Roller aes for Enine onnectin Rods are classified as shown in Table 2. When the classification symbol is not indicated in the identification number, the classification symbol "B2" is applied. The tolerance of the cae width B c is But caes with marks in the B c column in the dimension tables are manufactured with the followin width tolerances Table 2 Tolerances of needle roller diameter lass Standard Model code Semi-standard Dimensions lassification symbol 1 B 2 B 4 B B B Supplemental code B2 Type of bearin Roller set bore diameter Roller set outside diameter Width of cae Tolerance of mean value of roller (See Table 2.) Tolerance of mean value of roller otes 1 The classification symbol is indicated at the end of the identification number. 2 Tolerances for circularity are based on JIS B 0-1 (Rollers for rollin bearins). learance unit: m Radial internal clearances are selected accordin to the type of enine and the operatin conditions ( speed, load, lubricatin conditions, etc.). If a bearin is used with an inadequate clearance, bearin troubles such as seizure, early flakin and noise increase may occur, leadin to an enine failure. Therefore, it is necessary to select the clearance carefully accordin to test results and experience. Recoended radial internal clearances are shown in Table. When operatin at hih speeds, it is recoended to select the upper limit of the clearance. Fit To obtain the recoended clearance shown in Table, it is eneral practice to match a connectin rod, crank pin or piston pin and needle roller cae of suitable tolerances for assembly. Precautions for Use When desinin a connectin rod, crank pin and piston pin, the followin precautions should be taken, because the raceways are subjected to loads under extremely severe conditions. 1 Material It is recoended to use carburizin steel because the raceways are subjected to fluctuatin loads with frequent and heavy shock loads. Generally, chromium molybdenum steel is used. ickel chromium molybdenum steel is also used. 2 Hardness The recoended surface hardness of the raceway is 00HV ( 4HR). While the effective hardenin depth differs dependin on the applications, the eneral value is Surface rouhness To minimize initial wear and to extend life, it is recoended that the surface rouhness of the crank pin and piston pin be 0.1 mr a or less, and the surface rouhness of the connectin rod lare end and small end bores be 0.2 mr a or less. 4 Accuracy ircularity and cylindricity of connectin rod, piston pin and crank pin are as shown in Table 4. 5 Parallelism and torsional accuracy of connectin rod bores L 0.02 and E 0.02 shown in Fi. 1 indicate the parallelism and torsional accuracy between the bi end and small end bores of the connectin rod, respectively. The tolerance rane is 0.04 or less per 0 in case of a eneral-purpose enine and 0.02 or less for a hih-speed enine such as a racin motorcycle enine. When these accuracy conditions are not satisfied, the axial forces on the needle roller cae and connectin rod will increase, directly leadin to a failure such as seizure. areful consideration is required. Table Recoended radial internal clearance unit: m Over Remark Incl. Bi end d p d p d p d p d p d p Small end d p is obtained usin the followin formula for roller pitch circle diameter in millimeters, and chanin the unit from millimeters to micrometers. Roller pitch circle = F w E w 2 Example for bi end Recoended clearance is; m Table 4 Accuracy of connectin rod, piston pin and crank pin unit: m Rane of Over Remark Incl. rank pin diameter d 1 Piston pin diameter d 2 Bi end bore D 1 Small end bore D 2 ircularity MAX. 1 2 ylindricity MAX. 2 4 ircularity ylindricity MAX. MAX. 2 4 Refer to Fi.1 for the dimension symbols. Fi =0.2kf=0.4lbs. 1=0.0inch

EEDLE ROLLER AGES FOR IE OETIG RODS eedle Roller aes for Bi End eedle Roller aes for Small End V 2.1 0 2.

00 0 1..2.5 54 1 0 0 00 00 1 00 000 0 0 0 0 V.5 V V V V V.5 2..5 4.5. 4.1 4..5.5 00 4 4 4 0 4 5 5 0 5 50 0 4 00 4 4 0 4 2 4 0 5 5.

00 ae uide type Outer surface uide Inner surface uide Inner surface uide Inner surface uide Outer

uide Inner surface uide Outer surface uide Inner surface uide Outer surface uide Inner surface uide

11 EEDLE ROLLER AGES FOR IE OETIG RODS eedle Roller aes for Bi End eedle Roller aes for Small End V V.5 V V V V V V V. V V.5 V V.5 V V V V.5 V ae uide type Outer surface uide Inner surface uide Inner surface uide Inner surface uide Outer surface uide Inner surface uide Outer surface uide Outer surface uide Outer surface uide Outer surface uide Inner surface uide Outer surface uide Inner surface uide Outer surface uide Inner surface uide Inner surface uide Inner surface uide 1=0.2kf=0.4lbs. 1=0.0inch

Structure and Features

Structure and Features eedle Roller aes for General Usae are bearins which display excellent performance. eedle rollers with extremely small dimensional variations in diameter are incorporated and retained