C-1 SLIDE GUIDE ROTARY BALL SPLINE BALL SPLINE TOPBALL PRODUCTS SLIDE BUSH SLIDE UNIT SLIDEROTARYBUSH STROKE BUSH SLIDE SHAFT SLIDE TABLE GONIO WAY

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1 ROARY C-

2 NB now offers a new standard in linear motion with OPBA. he OPBA slide bush is a high performance bushing with three times the load capacity, capable of providing up to 27 times normal travel life of a conventional slide bushing. OPBA is available in a variety of configurations to fit various service conditions. NB's self-aligning OPBA can be designed into many different applications such as factory automated equipment, machine tools, industrial machines, electrical equipment, optical and measuring instruments. In the early stages of NB's development of OPBA, careful thought and consideration was given to such factors as quality, cost, performance and interchangeability. he results of these efforts are reflected in the OPBA features. OPBA EAURES. Increased oad Capacity: NB's uniquely designed ground load plate provides circular arch contact to the ball element resulting in a greater dispersion of the load, enabling OPBA to provide three times the load capacity of conventional slide bushings. 4. loating Integral iper Seal: NB's unique floating seal design allows for selfalignment while maintaining equal and constant contact to the shaft. Seals do not add to the overall length of the bushing allowing for more compact designs. 2. onger ravel ife: Dispersed stress on the load plate provides OPBA up to 27 times the travel life of conventional slide bushings. 3. Self Aligning Capability: oad plates are thinner at the ends to provide a pivot point at the center of the plate. he center acts as a fulcrum to compensate for any slight misalignment between the shaft and the housing bore that might be caused by inaccurate machining, mounting errors or shaft deflection. igure C- Illustrating circular arch design and ground surface raceway 5. Clearance Adjustable: OPBA load plates are designed to "float" in the outer sleeve which allows for clearance between the ball elements and shaft to best suit application requirements. 6. Cost Effectiveness: OPBA's higher load capability and longer travel life enables the use of smaller components such as bushings, housings and shafts, reducing material cost and the overall cost of the system. onger travel life also extends replacement periods and reduce maintenance cost. igure C-2 Illustrating floating seal and self-aligning feature Circular arch design floating seal round surface raceway Self-aligning feature C-2

3 YPES ROARY OPBA closed type open type K K-OP KA etric series KA- P.C-8 P.C-8 -OP A Inch series A- P.C- P.C- closed type P.C-2 P.C-3 J P.C-8 J- P.C-9 OPBA unit adjustable type open type KE KE- P.C-2 P.C-2 P.C-4 P.C-5 adjustable-open type KD P.C-6 KD- P.C-7 C-3 D P.C-22 D- P.C-23

4 RAED IE he life of a slide bush can be easily calculated with the load rating of the bush, shaft hardness and applicable load. However, in many cases, slide bushing failure may be caused by improper design of peripherals, including the shaft and housing, inappropriate mounting or improper operation. Serious consideration of these peripheral factors, in addition to load rating, are highly recommended when designing a slide bush application. Basic Dynamic oad Rating and ife Expectancy: he basic dynamic load rating is the load which allows a rating life of 5km, without changing its magnitude and direction. he rating life can be obtained from the following equation. C 3 = 5 Equation () P : travel life (km) C : basic dynamic load rating (N) P : load (N) igure C-3: Slide Bush ife Km 5, 4, 3, 2,, 5, 4, 3, 2, 6,6, igure C-3 shows the relationship between rating life () and load ratio(c/p). In the practical use of a bushing, other factors that affect the life, such as shaft hardness and load condition should be considered. he equation for calculating bushing life considering these additional factors is: fh C fw P 3 = 5 Equation (2) rating life 2,, fh : hardness coefficient (See igure C-4) fw : load coefficient (See able C-) 4 ife time can be calculated by obtaining the travelling distance per unit of time as follows: 3 h= Equation (3) 2 s N distance coefficient =P/C 2 h : life time (hr) s : stroke length (m) N : stroke frequency per min. (cpm) : travel life (km) C-4

5 oad coefficient (fw): hen calculating the bush load, it is necessary to accurately obtain weight, inertial force based on speed, moment load and each transition as time passes. However, it is difficult to calculate those values accurately because reciprocating motion involves the repetition of starts and stops as well as vibration and inpact. A more practical approach is to obtain the load coefficient by taking the actual operating conditions into account. able C-: oad Coefficient OPERAIN CONDIIONS operation at low speed (5m/min. or less) without impulsive shock from outside operation at intermediate speed (6m/min.or less) without impulsive shock operation at high speed (over 6m/min.) with impulsive shock Hardness Coefficient (fh): he shaft must be hardened to over 58HRC when a slide bush is used. If not properly hardened, permissible load is lowered and the life of the bushing will be shortened. igure C-4: Hardness coefficient hardness coefficient (fh) fw raceway hardeness H RC C-5 Examples of Calculations: () ife expectancy when NB's OPBA K 25 is used under the following conditions: oad per bush: 668N Stroke length:.2m Rate of cycles/min: 35 Shaft hardness: 6HRC rom the basic dynamic load of K25 is 378N. hardness coefficient(fh) is., and the operating speed can be calculated as.4km/min. herefore, the load coefficient(fw) is considered as.. Using Equation () (Page C-4) = 5=9,6km 668 Using Equation (3) (Page C-4) 9,6 3 h = =,8hours (2) Selection of for the application Expected life: 5, hours Number of bushings in the carriage: 4 ross weight on the carriage: 668N Stroke length:.9km raveling speed:.3km/min. Shaft hardness: 6-64HRC he life expected in traveling distance is: =5,.3 6 =27,km(2.7 4 ) rom Equation (2) 3 27 fw C= P=2,4N 5 fh Note that: fh=., fw=.5, P=668/4=67N As a result, the OPBA that is able to handle this load is: K2. ROARY

6 Basic Static oad Rating: If a slide bush is loaded when it is in a stationary condition or working at a low speed, a permanent elastic deformation is formed on the rolling element. he deformation prevents smooth movement of the bushing. o eliminate this possibility, the basic static load rating must not be exceeded. Relation Between Ball Circuits and oad Rating: he load rating of a slide bush varies according to the loaded position on the circumference. he value in the dimensional table indicates the lowest load rating with the load placed on top of one ball circuit. If the slide bush is used with two ball circuits loaded uniformly, the value will be greater. able C-2 shows the load ratio for the number of ball circuits in each case. Clearance and it: An appropriate clearance between the slide bush and shaft is required in OPBA operation. Inadequate clearance may cause early failure and/or poor, rough movement. Proper clearance is determined by shaft diameter and housing bore. able C-3 and C-4 shows NB's recommended tolerances of the shaft and housing bore in order to maintain the appropriate clearance. able C-3: Recommended olerance for Shaft Dia. and Housing Bore able C-2: Optional oad Positions NUBER O ROS Co (OAD RAIN SPECIIED ON HE ABE) Comax (AXIU OAD RAIN) OAD RAIO Comax/Co Co Co,44,463,28 Co Comax Comax Comax able C-4: Recommended olerance for Shaft Dia. and Housing Bore part number K K2 K6 K2 K25 K3 K4 dr mm shaft dia. tol. (h6) m 3 / 6 housing bore D mm tol. (H7) m / dr shaft dia. tol. (g6) housing bore. D tol. (H7) C-6

7 Shaft and Housing: o optimize NB OPBA performance, high precision shafts and housings are required.. Shaft: Dimensional tolerance, surface finish and hardness greatly affect the traveling performance of the OPBA. he shaft must be manufactured to the following tolerances. A. A surface finish of.4ra or less. B. Hardness of 6 HRC or more. Hardness less than 6 HRC decreases the life considerably and reduces the permissible load. C. he correct tolerance of the shaft diameter is recommended on able C-3 and C-4 (Page C-6). igure C-5 Use of holding plates igure C-6 Adjustable type housing ROARY he NB Slide Shaft is an ideal component manufactured to these specifications. or details, please refer to Page -2 to Housing: here are a wide range of designs and manufacturing techniques for mounted housings. NB pre-engineered slide units are also available. or proper fit refer to able C-3 and C-4 (Page C-6). ounting: OPBA is designed to be press fitted into the housing bore. hen inserting bushing, however, don't apply excess force nor shock load which may cause permanent damage. Examples of ounting igure C-7 Use of external retaining rings igure C-8 Open type housing igures C-5 to C-8 illustrate mounting methods as examples. C-7

8 A YPE Block ype (Inch Series) part number structure example A 2 UU A type seal blank without seal UU seals on both sides 4-S E.2 B. C. h.2 self-aligning in all directions oil hole* part number A 4UU A 6UU A 8UU A UU A 2UU A 6UU A 2UU A 24UU A 32UU nom. shaft dia. /4 3/8 /2 5/8 3/4 -/4 -/2 2 h E major dimensions * Provided with push-in oil fitting for /4" to /2" s. Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-8

9 A- YPE Double-ide Block ype (Inch Series) ROARY part number structure example A type double-wide type A 2 UU 4-S E.2 seal blank without seal UU seals on both sides B. h.2 C. part number A 4UU A 6UU A 8UU A UU A 2UU A 6UU A 2UU A 24UU nom. shaft dia. /4 3/8 /2 5/8 3/4 -/4 -/2 h E major dimensions oil hole* * Provided with push-in oil fitting for /4" to /2" s. Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-9

10 J YPE Clearance Adjustable Block ype (Inch Series) part number structure example J 2 UU J type seal blank without seal UU seals on both sides E.2 4-S B. C. h.2 self-aligning in all directions oil hole* part number J 4UU J 6UU J 8UU J UU J 2UU J 6UU J 2UU J 24UU J 32UU nom. shaft dia. /4 3/8 /2 5/8 3/4 -/4 -/2 2 h E major dimensions * Provided with push-in oil fitting for /4" to /2". Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-2

11 J- YPE Clearance Adjustable Double-ide Block ype (Inch Series) ROARY part number structure example J type double-wide type J 2 UU E.2 4-S B. C. seal blank without seal UU seals on both sides h.2 part number J 4UU J 6UU J 8UU J UU J 2UU J 6UU J 2UU J 24UU nom. shaft dia. /4 3/8 /2 5/8 3/4 -/4 -/2 h E major dimensions oil hole* * Provided with push-in oil fitting for /4" to /2". Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-2

12 D YPE Open Block ype (Inch Series) part number structure example D 2 UU D type seal blank without seal UU seals on both sides E 4-S B..2 C..2 h self-aligning in all directions h 3 oil hole* part number D 8UU D UU D 2UU D 6UU D 2UU D 24UU D 32UU nom. shaft dia. /2 5/8 3/4 -/4 -/2 2 h E major dimensions * Provided with push-in oil fitting for /4" to /2" only. Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass h B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-22

13 D- YPE Double-ide Open Block ype (Inch Series) ROARY part number structure example D type double-wide type D 2 UU E 4-S B. h.2.2 seal blank without seal UU seals on both sides C. part number D 8UU D UU D 2UU D 6UU D 2UU D 24UU nom. shaft dia. /2 5/8 3/4 -/4 -/2 h E h 3 major dimensions oil hole* * Provided with push-in oil fitting for /4" to /2". Sizes from 5/8" to 2" offer a /4-28 tapped hole with a plug for adding a fitting if desired. basic load rating mounting dimensions dynamic static mass h B C S C Co lbs. lbs. lbs = 25.4mm lbs.454kg lbs 4.448N C-23