Ball Spline Types LT and LF

Transcription

1 Ball Spline Types and LF Ball Spline nut Snap ring Seal Retainer Spline shaft Fig. Construction of Ball Spline Type Construction and Features Ball Spline types and LF have four or six trains of loadbearing balls to hold two or three crests on the spline shaft from both sides, so that an appropriate preload is applied without trouble. The balls are held in place by the retainer, which is made of special synthetic resin and built into the interior of the spline nut. The retainer causes the balls to circulate in line and prevents them from falling off if the spline shaft is removed. B7

2 High loadcarrying capability The raceways are formed into circulararc grooves with a radius approximately the same as that of the ball, and are designed to permit angular contact. Types and LF therefore have a high loadcarrying capability in both the radial and torqueapplying directions. Zero angular backlash The preloaded angularcontact design, in which two trains of balls arranged opposite another hold a crest on the spline shaft at a contact angle of, reduces the angular backlash in the rotational direction to zero and increases rigidity. High rigidity A wide contact angle and an appropriate level of preload combine to provide high torque and moment rigidity. Simple assembly Balls do not fall off if the spline nut is removed from the spline shaft. As a result, assembly, maintenance, and checking are simple. (This does not apply to type or.) BII Types and Features Cylindrical Ball Spline Type Flanged Ball Spline Type LBF The spline nut is of a straight cylindrical shape. When it is necessary to apply a torque, insert a key into the keyway. Type is the most compact of all Ball Spline types. The spline nut can be attached to the housing via the flange, making assembly simple. It is most suitable where the housing may deform if a keyway is cut thereon, and where the housing width is limited. Knock pins that can be driven into the flange completely eliminate the angular backlash that occurs in fitting part. B7

3 Precision Solid Spline Shaft (standard type) Special Spline Shaft The raceways of the spline shaft are cut into the shaft to a high degree of precision. A spline nut is attached to the resulting spline shaft. A shaft with a greater diameter at its ends or midpoint can be produced upon request, by machining it to the required spline shape. Hollow Spline Shaft (Type K) Hollow Spline Shaft (Type N) (Thick wall) (Thin wall) This type is made hollow through cold drawing, to enable it to accommodate pipes and wires and vent air, or to reduce its weight. B7

4 Standard Ball Spline (standard offtheshelf item) BII Precisionground spline shafts of various standardized lengths ( through ) and a variety of spline nuts can be freely combined to your specifications, enabling quick delivery at a low price. For the standards, see page B. B7

5 See page B. SplineShaft Strength Clearance in the Rotational Direction The clearance of the Ball Spline in the rotational direction significantly affects the rigidity and precision of the spline nut. It is very important, therefore, to determine the appropriate clearance for the intended uses. As repeated swiveling and reciprocal linear motions cause heavy vibration and impact, preloading the system drastically improves its service life and accuracy. We will determine the optimum clearance for your operating conditions. Please contact us. Table presents the clearances in the rotational direction for Ball Spline types and LF. See page B. Clearance in the rotational direction CM CL Normal Accuracy Standards Operating conditions High rigidity is required; vibration and impact are heavy. Moment loads must be borne by a single spline nut. Overhang loads and moments are applied. Highly reproducible accuracy is required. Alternate loads are applied. Smooth movement should be achieved with only a low magnitude of force. Torque is continually applied in a given direction. Symbol Nominal shaft diameter Table Clearance in the Rotational Direction Normal Light preload No symbol CL ~ + ~ ~ + ~ ~ + ~ ~ + ~ ~ + ~ Unit: µm Medium preload CM 9 ~ ~ ~ ~ ~ Note: For normal clearance, do not append any symbol to a model number. For medium and light preloads, append CM or CL. (For modelnumber coding, see page B7.) B7

6 Housing InnerDiameter Tolerance See page B7. Spline Shaft Splineshaft crosssectional shape and outerdiameter tolerance For Ball Spline types and LF, spline shafts can be provided upon request. When requesting an estimate or placing an order, specify the splineshaft crosssectional shape. Hollowsplineshaft inner diameter For Ball Spline types and LF, the hollow spline shafts shown in Table are available as standard components. They are lightweight and can be used as a hydropneumatic passage. BII Table presents the splineshaft minor diameters and tolerances for the standard splineshaft outer diameters. Type K Type N or lower or higher Table SplineShaft CrossSectional Shape Unit : mm Nominal shaft diameter Minor diametr d Outer diameter D Outerdiameter tolerance Nominal shaft diameter Note: Table Standard HollowSplineShaft Dimensions Unit: mm Outer diameter D Hollow diameter d Type K Mass kg/m Hollow diameter d 9 Type N Mass kg/m The standard hollow spline shaft comes in two types, K and N. Specify the required type by appending K or N to the desired model number. Nominal shaft diameter dp Table Ball CentertoCenter Shaft Diameter Unit: mm B7

7 Length of incomplete spline portion in special splineshaft To obtain a splineshaft end or midpoint diameter greater than the minor diameter (d), an incomplete spline portion is required to provide a recess under the grinding wheel. Table shows the relationship between the incomplete spline length (S) and the flange diameter (D ). This, however, does not apply to spline shafts with an overall length of, mm or more. For spline shafts with an overall length greater than, mm, contact us. Grindingwheel radius Table Incomplete Spline Length: S Miniature type Flange diameter Nominal shaft diameter D Unit: mm Standard type Flange diameter Nominal D shaft diameter Unit: mm B7

8 Accessories Ball Spline type comes with one of the standard keys listed in Table. BII Table Standard Key for Unit: mm Model No. Width b Height h Length l Tolerance (p7) Tolerance (h9) Tolerance (h) R C B77

9 ModelNumber Coding The coding of Ball Spline model numbers is as specified below. UU CL + L P Special symbol No symbol: No special specifications K: Standard hollow spline shaft N: Standard hollow spline shaft F: Surface treatment provided (e.g., APC treatment) M: Special material used (e.g., SUSC) * If it is necessary to use more than one symbol, arrange them in alphabetical order. Accuracy symbol No symbol: Normal grade H: High grade P: Precision grade Splineshaft overall length (mm) Special symbol No symbol: No special specifications M: Special material used (e.g., SUSC for balls) F: Surface treatment provided (e.g., APC treatment) E: Cylinder reworked * If it is necessary to use more than one symbol, arrange them in alphabetical order. Rotationaldirection clearance symbol No symbol: Normal clearance CL: Light preload CM: Medium preload Seal symbol No symbol: No seal provided UU: Rubber seals provided on both sides U: Rubber seal provided on one side Classification symbol S: Standard Model number (splinenut shape) Number of spline nuts attached to a shaft (no symbol when this is ) B7

10 B79 BII

11 Standard Ball Spline Type (Standard offtheshelf item) Model No. S S S S S S S S S S S S S S S S S S S S Outer diameter D Tolerance Length Splinenut dimensions L Tolerance.. Keyway dimensions Oil b H t +. k r hole d d h Notes: The basic torque and load ratings are for singlespline nut use. Only the spline section is inductionhardened to a surface hardness of HRC through HRC. Both the rotationaldirection clearance and accuracy grade are normal. If a model with seals is required, please specify. B

12 BII S or lower Unit: mm Splineshaft dimensions Length Chamfer d R L(l C C ) kn Tolerance Basic torque rating C kn Basic load rating (radial) C T Nm C T. ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) 7( ) ( ) ( 7) ( ) () ( ) ( ) ( ) () 7( ) () 9( ) () ( ) 7() () *() () The spline nut accommodates a synthetic resin retainer. For modelnumber coding, see page B7. For lengths marked with a *, dimension l is mm. B

13 Standard Ball Spline Type LF (Standard offtheshelf item) d drill through d spotfacing depth h Model No. LF LF LF LF S S S S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S LF S Outer diameter D 7 Splinenut dimensions Flange Length dimensions L D H F PCD Mounting hole d r d h d Tolerance Tolerance Tolerance Oil hole d h7 Notes: The basic torque and load ratings are for singlespline nut use. Only the spline section is inductionhardened to a surface hardness of HRC through HRC. Both the rotationaldirection clearance and accuracy grade are normal. If a model with seals is required, please specify. The spline nut accommodates a retainer made of synthetic resin. B

14 BII LFS or lower Unit: mm Splineshaft dimensions Length Chamfer d l L (l ) C C Tolerance kn Basic torque rating C kn Basic load rating (radial) C T Nm C T Nm. ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) 7 ( ) ( ) ( 7) ( ) () ( ) ( ) ( ) () 7 ( ) () 9 ( ) () ( ) 7 () () * () () For modelnumber coding, see page B7 In singlesplinenut use, the flange is pointed toward the splineshaft terminal (to the left in the dimension drawing). For lengths marked with a *, dimension l is mm. B

15 Type or lower or higher Model No. Note) Note) Splinenut dimensions Keyway Outer diameter Length dimensions D L b t l r Tolerance H +. Tolerance Oil hole d Notes: The spline nut accommodates a retainer made of synthetic resin that generates low noise during operation. (There is no hightemperature model for type ). and do not have retainers, so do not remove the shaft from the spline nut, as doing so causes the balls to fall off. If a model with seals is required, please specify. For modelnumber coding, see page B7. B

16 BII Unit: mm Shaft diameter d h7 No. of trains of balls Basic load rating C kn C kn Basic torque rating C T Nm C T Nm Static permissible moment M A. ) Nm Mass Spline Spline ) M A. nut shaft Nm g kg/m Notes: ) M A. represents the permissible moment in the axial direction when a single spline nut is used, as shown below. ) M A. represents the permissible moment in the axial direction when two closely linked spline nuts are used, as shown below. (Due to insufficient stability of single spline nut in accuracy, we recommend the use of closely linked double spline nuts.) B

17 Type LF d drill through d spotfacing depth h d drill through d spotfacing depth h or lower or higher Model No. Splinenut dimensions Outer diameter Length Flange dimensions D L D H F C, r Tolerance Tolerance Tolerance Oil hole d Shaft diameter PCD d h7 LF LF LF LF LF LF LF LF LF LF ,.. Notes: The spline nut accommodates a retainer made of synthetic resin that generates low noise during operation. (There is no hightemperature model). If a model with seals is required, please specify. For modelnumber coding, see page B7. B

18 BII Unit: mm No. of trains of balls Mounting hole d d h Basic load rating C kn C kn Basic torque rating C T Nm C T Nm Static permissible moment M A. ) Nm Mass ) Spline Spline M A. nut shaft Nm g kg/m Notes: ) M A. represents the permissible moment in the axial direction when a single spline nut is used, as shown below. ) M A. represents the permissible moment in the axial direction when two closely linked spline nuts are used, as shown below. (Due to insufficient stability of single spline nut in accuracy, we recommend the use of closely linked double spline nuts.) B7

19 Recommended Type SplineShaft End Shape (for support) Unit : mm Model No. D Tolerance L M l S t. M. M. 7 M M. M. M. M M. M M M M 7. M M7. M M. M. M. M M B