HB 7808-2006 Curvic coupling
1 Scope
This standard specifies the tooth profile, dimension series, presentation and marking of curvic coupling.
This standard is applicable to the design of curvic coupling for aero-engine.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding any corrections), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For undated references, the latest edition of the normative document applies.
GB/T 17451-1998 Technical drawings - General principles of presentation - Views
3 Terms and definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
convex teeth
coupling machined with the grinding surface on the inside diameter of the grinding wheel, see Figure 1
3.3
nodal plane
datum plane for determining the position and geometric elements of the coupling
3.4
outside diameter
φA
maximum radial dimension on the nodal plane of curvic coupling
3.5
pitch diameter
average radial dimension on the nodal plane of curvic coupling
3.6
inside diameter
φB
minimum radial dimension on the nodal plane of curvic coupling
3.7
height of tooth head
S
distance from tooth head to nodal plane of the coupling
3.8
height of chamfer
T
height of chamfer of the coupling
3.9
height of tooth root
P
distance from nodal plane to tooth root of the coupling
3.10
height of tooth
distance from tooth head to tooth root of the coupling in a direction perpendicular to the nodal plane
3.11
tooth profile
normal tooth profile of the basic rack, which refers to the ideal coupling with infinite diameter without error
3.12
datum line
intersection of the nodal plane and the plane passing through the axis, used to determine the axial parameters
3.13
pressure angle
α
acute angle between the normal line and the datum line at any point on the tooth profile
3.14
tooth thickness
chordal tooth thickness at the pitch diameter (convex teeth) or outside diameter (concave teeth) on the nodal plane
3.15
tooth width
width of the curvic coupling in radial direction
3.16
tooth pitch
outside diameter distance between the corresponding tooth flanks of two adjacent couplings, measured within the nodal plane
3.17
dimension of superpose
distance between the nodal plane and the specified end face for a part having a coupling on one end; or distance between two nodal planes for a part having couplings on both ends
3.18
height of gable bottom
height of the gable bottom at the root of the coupling
3.19
radius of curve
radius of the grinding wheel on the nodal plane, as shown in Figure 3
Contents
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Tooth profile
5 Dimension series of curvic coupling
6 Presentation and marking of curvic coupling
