Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is developed in accordance with the rules given in GB/T 1.1-2020.
This standard replaces GB/T 10089-1988 Accuracy of cylindrical worm and wormwheel.
The following main changes have been made with respect to GB/T 10089-1988:
——The forward of this standard is added;
——The application scope of this standard is modified (see Clause 1; Clause 1 of Edition 1988);
——The references of GB/T 1800, GB/T 10086 and GB/T 10087 are deleted, and reference of GB/T 3374.2 is added (see Clause 2; Clause 2 of Edition 1988);
——The term definition and code of worm and wormwheel wheel tooth dimension parameter deviation are revised, in which helix deviation of one worm revolution, worm axial pitch cumulative deviation, wormwheel k pitches cumulative deviation, wormwheel radial comprehensive deviation, tooth thickness deviation, center distance deviation of worm gear pair, mid-plane offset of worm gear pair, shaft angle deviation of worm gear pair and backlash of worm gear pair are deleted, and the term definition and code of adjacent pitch deviation are added (see Clause 3; Clause 3 of Edition 1988)
——The clause of “Symbols” is added (see Clause 4);
——The requirements on the composition of accuracy system and so on are modified, and the provisions on tolerance groups are deleted (see Clause 5; Clause 4 of Edition 1988);
——The requirements on the gear blank are deleted (Clause 5 of Edition 1988);
——The calculation equation of allowable deviation is modified (see Clause 6; Annex A of Edition 1988);
——The clause of “Inspection rules” is added (see Clause 7);
——Parameter segment and values in the table for allowable deviation are modified (see Clause 8; Clause 6 of Edition 1988);
——The requirements of center distance deviation of worm gear pair, mid-plane offset of worm gear pair, shaft angle deviation of worm gear pair and backlash of worm gear pair are deleted (see Clauses 7 and 8 of Edition 1988);
——The requirements of other descriptions and drawing indications are deleted (see Clauses 9 and 10 of Edition 1988).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This standard was proposed by and is under the jurisdiction of National Technical Committee on Gears of Standardization Administration of China (SAT/TC 52).
The previous edition of this standard is as follows:
——GB/T 10089-1988.
Accuracy of cylindrical worm and wormwheel
1 Scope
This standard specifies the accuracy of cylindrical worm and wormwheel transmission mechanism.
It is applicable to cylindrical worm and wormwheel transmission mechanism with shaft angle of ∑=90°, maximum module m=40mm and maximum reference diameter d=2,500mm. Cylindrical worm and wormwheel transmission mechanism with the maximum reference diameter d > 2,500mm may be used with reference to this standard.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies
GB/T 3374.2 Vocabulary of gear terms - Part 2: Definitions related to wormwheel geometry
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 3374.2 and the following apply.
3.1 worm deviation
3.1.1
total profile deviation
Fα1
axial distance between two design profile traces that contain the actual profile traces within the value range Lα1 of the axial section (the working range of the profile), which is shown in Figure 1
Figure 1 Total profile deviation Fα1 in axial section of ZC worm
In the profile inspection diagram (see Figure 2), the total profile deviation Fα1 is the distance between two design profile traces (measured perpendicular to the design profile traces).
Note: In Figure 2, the design profile is irrelevant to the tooth surface shapes A, N, I, K and C of the worm and marked with a straight line, and the actual profile is included in the drawn range.
Figure 2 Profile inspection diagram within the value range of Lα1
3.1.2
profile form deviation
ffα1
distance between two auxiliary lines parallel to the average profile trace (measured perpendicular to the design profile trace, which is shown in Figure 2) within the value range Lα1 of axial section
Note: This standard does not give the allowable profile form deviation ffα1.
3.1.3
profile slope deviation
fHα1
distance between two auxiliary lines parallel to the design profile trace intersecting with the average profile trace within the value range Lα1 of the axial section (see Figure 2)
Note: This standard does not give the allowable profile slope deviation fHα1.
3.1.4
axial pitch deviation
fpx
difference between the actual pitch and the nominal pitch in the axial section of the worm
3.1.5
adjacent axial pitch deviation
fux
difference between two adjacent pitches in the axial section of the worm
3.1.6
radial run-out deviation
Fr1
maximum radial variation of the measuring head relative to the leading axis of the worm when the measuring head contacts with the tooth surface in the middle of the tooth depth on both sides in the tooth slot in any rotation range of the worm
Note: The radial run-out deviation is caused by the distance and cross angle between the leading axis of the worm determined by the axis of the cylindrical surface at the midpoint of the wormwheel teeth and the position of the worm bearing.
3.1.7
lead deviation
Fpz
difference between actual dimension and nominal dimension of worm lead
3.2 worm deviation
3.2.1
single pitch deviation
fp2
difference between the actual pitch and the nominal pitch on the wormwheel reference circle
When measured by relative method, nominal pitch refers to the average value of all actual pitches.
Note: When the actual pitch is greater than the average value, it is a positive deviation; otherwise, it is a negative one.
3.2.2
total cumulative pitch deviation
Fp2
maximum absolute value of the difference between the actual arc length and the nominal arc length between any two tooth surfaces on the same side on the wormwheel reference circle
3.2.3
adjacent pitch deviation
fu2
actual dimension difference between two adjacent pitches of the right or left tooth surface of wormwheel
3.2.4
total profile deviation
Fα2
distance between two design profile traces that contain the actual profile traces within the value range of the given section of the wheel teeth
3.2.5
radial run-out deviation
Fr2
maximum variation of the radial distance from the measuring head relative to the axis of the worm when the measuring head contacts with the tooth surface in the middle of the tooth depth on both sides in the tooth slot in any revolution range of the worm
Note: The radial run-out deviation is caused by the eccentricity of the wheel teeth, the nonuniformity of tooth slot width caused by the pitch deviation between the right and left tooth surfaces and the offset (eccentricity) of the wheel tooth axis relative to the leading axis.
3.3 engagement deviation
3.3.1
single-flank engagement deviation
F′i
fluctuation of actual and theoretical rotation position of wormwheel, wherein the theoretical rotation position is determined by the rotation of the worm and when the rotating direction is determined (left or right tooth surface engagement), the single-flank engagement deviation is equal to the sum of the maximum deviations from the initial position within one revolution of the wormwheel (see Figure 3)
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 Composition of accuracy system
6 Calculation equation of allowable deviation of worm and wormwheel with Class 5 accuracy
7 Inspection rules
8 Allowable deviation of dimension parameter of wheel tooth
Annex A (Normative) Requirements of worm gearing engagement pattern
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is developed in accordance with the rules given in GB/T 1.1-2020.
This standard replaces GB/T 10089-1988 Accuracy of cylindrical worm and wormwheel.
The following main changes have been made with respect to GB/T 10089-1988:
——The forward of this standard is added;
——The application scope of this standard is modified (see Clause 1; Clause 1 of Edition 1988);
——The references of GB/T 1800, GB/T 10086 and GB/T 10087 are deleted, and reference of GB/T 3374.2 is added (see Clause 2; Clause 2 of Edition 1988);
——The term definition and code of worm and wormwheel wheel tooth dimension parameter deviation are revised, in which helix deviation of one worm revolution, worm axial pitch cumulative deviation, wormwheel k pitches cumulative deviation, wormwheel radial comprehensive deviation, tooth thickness deviation, center distance deviation of worm gear pair, mid-plane offset of worm gear pair, shaft angle deviation of worm gear pair and backlash of worm gear pair are deleted, and the term definition and code of adjacent pitch deviation are added (see Clause 3; Clause 3 of Edition 1988)
——The clause of “Symbols” is added (see Clause 4);
——The requirements on the composition of accuracy system and so on are modified, and the provisions on tolerance groups are deleted (see Clause 5; Clause 4 of Edition 1988);
——The requirements on the gear blank are deleted (Clause 5 of Edition 1988);
——The calculation equation of allowable deviation is modified (see Clause 6; Annex A of Edition 1988);
——The clause of “Inspection rules” is added (see Clause 7);
——Parameter segment and values in the table for allowable deviation are modified (see Clause 8; Clause 6 of Edition 1988);
——The requirements of center distance deviation of worm gear pair, mid-plane offset of worm gear pair, shaft angle deviation of worm gear pair and backlash of worm gear pair are deleted (see Clauses 7 and 8 of Edition 1988);
——The requirements of other descriptions and drawing indications are deleted (see Clauses 9 and 10 of Edition 1988).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This standard was proposed by and is under the jurisdiction of National Technical Committee on Gears of Standardization Administration of China (SAT/TC 52).
The previous edition of this standard is as follows:
——GB/T 10089-1988.
Accuracy of cylindrical worm and wormwheel
1 Scope
This standard specifies the accuracy of cylindrical worm and wormwheel transmission mechanism.
It is applicable to cylindrical worm and wormwheel transmission mechanism with shaft angle of ∑=90°, maximum module m=40mm and maximum reference diameter d=2,500mm. Cylindrical worm and wormwheel transmission mechanism with the maximum reference diameter d > 2,500mm may be used with reference to this standard.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies
GB/T 3374.2 Vocabulary of gear terms - Part 2: Definitions related to wormwheel geometry
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 3374.2 and the following apply.
3.1 worm deviation
3.1.1
total profile deviation
Fα1
axial distance between two design profile traces that contain the actual profile traces within the value range Lα1 of the axial section (the working range of the profile), which is shown in Figure 1
Figure 1 Total profile deviation Fα1 in axial section of ZC worm
In the profile inspection diagram (see Figure 2), the total profile deviation Fα1 is the distance between two design profile traces (measured perpendicular to the design profile traces).
Note: In Figure 2, the design profile is irrelevant to the tooth surface shapes A, N, I, K and C of the worm and marked with a straight line, and the actual profile is included in the drawn range.
Figure 2 Profile inspection diagram within the value range of Lα1
3.1.2
profile form deviation
ffα1
distance between two auxiliary lines parallel to the average profile trace (measured perpendicular to the design profile trace, which is shown in Figure 2) within the value range Lα1 of axial section
Note: This standard does not give the allowable profile form deviation ffα1.
3.1.3
profile slope deviation
fHα1
distance between two auxiliary lines parallel to the design profile trace intersecting with the average profile trace within the value range Lα1 of the axial section (see Figure 2)
Note: This standard does not give the allowable profile slope deviation fHα1.
3.1.4
axial pitch deviation
fpx
difference between the actual pitch and the nominal pitch in the axial section of the worm
3.1.5
adjacent axial pitch deviation
fux
difference between two adjacent pitches in the axial section of the worm
3.1.6
radial run-out deviation
Fr1
maximum radial variation of the measuring head relative to the leading axis of the worm when the measuring head contacts with the tooth surface in the middle of the tooth depth on both sides in the tooth slot in any rotation range of the worm
Note: The radial run-out deviation is caused by the distance and cross angle between the leading axis of the worm determined by the axis of the cylindrical surface at the midpoint of the wormwheel teeth and the position of the worm bearing.
3.1.7
lead deviation
Fpz
difference between actual dimension and nominal dimension of worm lead
3.2 worm deviation
3.2.1
single pitch deviation
fp2
difference between the actual pitch and the nominal pitch on the wormwheel reference circle
When measured by relative method, nominal pitch refers to the average value of all actual pitches.
Note: When the actual pitch is greater than the average value, it is a positive deviation; otherwise, it is a negative one.
3.2.2
total cumulative pitch deviation
Fp2
maximum absolute value of the difference between the actual arc length and the nominal arc length between any two tooth surfaces on the same side on the wormwheel reference circle
3.2.3
adjacent pitch deviation
fu2
actual dimension difference between two adjacent pitches of the right or left tooth surface of wormwheel
3.2.4
total profile deviation
Fα2
distance between two design profile traces that contain the actual profile traces within the value range of the given section of the wheel teeth
3.2.5
radial run-out deviation
Fr2
maximum variation of the radial distance from the measuring head relative to the axis of the worm when the measuring head contacts with the tooth surface in the middle of the tooth depth on both sides in the tooth slot in any revolution range of the worm
Note: The radial run-out deviation is caused by the eccentricity of the wheel teeth, the nonuniformity of tooth slot width caused by the pitch deviation between the right and left tooth surfaces and the offset (eccentricity) of the wheel tooth axis relative to the leading axis.
3.3 engagement deviation
3.3.1
single-flank engagement deviation
F′i
fluctuation of actual and theoretical rotation position of wormwheel, wherein the theoretical rotation position is determined by the rotation of the worm and when the rotating direction is determined (left or right tooth surface engagement), the single-flank engagement deviation is equal to the sum of the maximum deviations from the initial position within one revolution of the wormwheel (see Figure 3)
Contents of GB/T 10089-2018
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 Composition of accuracy system
6 Calculation equation of allowable deviation of worm and wormwheel with Class 5 accuracy
7 Inspection rules
8 Allowable deviation of dimension parameter of wheel tooth
Annex A (Normative) Requirements of worm gearing engagement pattern
