What Is a Spline?

The spline joint is composed of an inner spline and an outer spline. The inner and outer splines are multi-tooth parts, the splines on the inner cylindrical surface are inner splines, and the splines on the outer cylindrical surface are outer splines. Obviously, spline coupling is a development in number of flat couplings. The spline has a standard structure.

Flat key couplings are commonly used for coupling gears or couplings with shafts with an interference fit. Usually splined joints such joints are not

In mechanical drawing, the spline key tooth mapping is more complicated. In order to improve the efficiency of drawing, many countries have developed spline drawing standards, and ISO standards have also been developed internationally. The Chinese national standard for mechanical drawing stipulates that for rectangular splines, the external splines are drawn in a view parallel to the axis of the projection plane, the large diameter is drawn with a thick solid line, and the small diameter is drawn with a thin solid line, and a part or all of the tooth shape is drawn with a section ; In the sectional view of the internal spline in the projection plane parallel to the axis, the large and small diameters are drawn with thick solid lines, and some or all of the tooth shapes are drawn with a partial view (Figure 1 [Rectangular spline drawing]). The end of the spline's working length and the end of its tail length are drawn with thin solid lines. For the involute spline, the drawing method is basically the same as that of the rectangular spline, but the dot circle and the graduation line need to be drawn with a dotted line ^[1]

National standard

Spline's current national standards

1 GB / T4459.3-2000 mechanical drawing spline representation 2000-12-01 implemented instead of GB / T 4459.3-1984

2 GB / T1144-2001 Rectangular spline dimensions, tolerances and inspections implemented on 2002-06-01, replacing GB / T 1144-1987

3 GB / T9167-2003 spline shaft milling machine precision inspection 2004-06-01 implemented instead of GB / T 9167-1988

4 GB / T17855-1999 Spline bearing capacity calculation method 2000-03-01 implemented

5 GB / T5103-2004 General technical requirements for involute spline hobs implemented on 2004-08-01, replacing GB / T 5103-1985

6 GB / T5102-2004 Involute spline broach technical requirements implemented on 2004-08-01, replacing GB / T 5102-1985

7 GB / T10081-2005 Rectangular inner spline length series 2005-12-01 implemented instead of GB / T 10081-1988

8 GB / T10952-2005 Rectangular spline hob 2005-12-01 implemented instead of GB / T 10952-1989

9 GB / T10919-2006 Rectangular spline gauge implemented 2006-08-01, replacing GB / T 10919-1989

10 GB / T5106-2006 Cylindrical straight tooth involute spline gauge 2006-12-01 implemented instead of GB / T 5106-1985

11 GB / T1592.3-2008 Agricultural tractor rear PTO shaft type 1, 2 and 3 Part 3: PTO shaft size and spline size, PTO shaft location 2009-02-01 implementation, replace GB / T 1592 -2003

12 GB / T5104-2008 Basic types and dimensions of involute spline hobs

13 GB / T3478.5-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 5: Inspection 2009-05-01 Implementation, replacing GB / T 3478.5-1995

14 GB / T3478.1-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 1: General implementation 2009-05-01, replacing GB / T 3478.1-1995

15 GB / T3478.4-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 4: 45 ° pressure angle dimension table 2009-05-01 implementation, replacing GB / T 3478.4-1995

16 GB / T3478.3-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 3: Implementation of 37.5 ° pressure angle dimension table 2009-05-01, instead of GB / T 3478.3-1995

17 GB / T3478.6-2008 Cylindrical straight-tooth involute spline (Metric modulus tooth side fit) Part 6: 30 ° pressure angle M value and W value implemented 2009-05-01, replacing GB / T 3478.6- 1995

18 GB / T3478.9-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 9: Measuring rod 2009-05-01 implemented instead of GB / T 3478.9-1995

19 GB / T15758-2008 spline basic term 2009-05-01 implemented, instead of GB / T 15758-1995

20 GB / T3478.2-2008 Cylindrical straight tooth involute spline (metric module tooth side fit) Part 2: 30 ° pressure angle dimension table 2009-05-01 implemented, instead of GB / T 3478.2-1995

21 GB / T3478.7-2008 Cylindrical straight-tooth involute spline (Metric modulus tooth side fit) Part 7: 37.5 ° pressure angle M value and W value implemented 2009-05-01, replacing GB / T 3478.7- 1995

22 GB / T18842-2008 conical straight tooth involute spline 2009-05-01 implementation, instead of GB / T 18842-2002

23 GB / T3478.8-2008 Cylindrical straight tooth involute spline (Metric modulus tooth side fit) Part 8: 45 ° pressure angle M value and W value implemented 2009-05-01, replacing GB / T 3478.8- 1995

24 GB / T24650-2009 Technical requirements for tractor spline shaft 2010-05-01

25 GB / T24666-2009 Technical requirements for agricultural spline shaft 2010-04-01

26 GB / T25657.1-2010 CNC spline shaft milling machine Part 1: Precision inspection implementation 2011-07-01

27 GB / T25657.2-2010 CNC spline shaft milling machine Part 2: Technical requirements 2011-07-01 implementation

28 GB / T5106-2012 Cylindrical straight tooth involute spline gauge 2012 No. 41

^[2]