RU2205364C1 - Method of measuring parameters of shaft keyway - Google Patents

Abstract

FIELD: measurement technology. SUBSTANCE: shaft 1 is located by its cylindrical surface in vee block 4 providing contact of sensitive contact tip 6 with said surface. Shaft 1 is turned to provide getting of sensitive contact tip 6 into keyway to be checked and its contact with bottom of keyway. Then reciprocating rotation is imparted to shaft 1 to provide perpendicularity of axis of reading unit 5 relative to bottom of keyway under checking and first reading is recorded which is depth of keyway. By turning and shifting rod 7 with feeler gauge, in turn touching of ball-shaped side surface 9 of feeler gauge with side surfaces 11 and 12 of keyway is provided and primary readings of indicator 10 are recorded. By turning and shifting rod 7, centering of ball-shaped side surface 9 in vee block 4 is provided, and initial reading of indicator 10 is recorded. Deviation from symmetry is determined by said primary and initial readings of indicator 10, and width of keyway under checking is determined with due account of diameter of ball-shaped side surface 9. Then shaft 1 is re-installed in vee block 4 with provision if contact of sensitive contact tip 6 with bottom of keyway in its end, and shaft 1 is again reciprocally rotated to provide perpendicularity of axis of reading unit 5 relative to bottom of keyway and second reading of unit 5 is recorded and deviation from parallelism of keyway bottom relative to axis of cylindrical surface is determined by difference in first and second readings of said unit. Rod 7 with feeler gauge is turned and shifted to provide touching of ball-shaped surface 9 of feeler gauge with side surface 11 of keyway under checking and secondary reading of indicator 10 is recorded. Size of skewness of keyway under checking is found by difference between secondary and primary readings of indicator 10 obtained at contact of ball-shaped side surface 9 with one and the same side surface of keyway. EFFECT: increased capability, improved accuracy of measurements. 2 dwg

Description

Technical field
The invention relates to measuring equipment and can be used in mechanical engineering, mainly for measuring the parameters of keyways on the shafts.

State of the art
A known method of measuring the parameters of the keyway, implemented in the device for monitoring the keyways and consisting in installing on the cylindrical surface of the shaft a housing made in the form of a prism, on which a slider is mounted with a fixed reading unit, the measuring tip of which is made with a flat base and side barrel-shaped surfaces, and the axis of said tip is parallel to the bisector plane of the prism, providing contact of the flat base surface of the measuring tip In order to contact the flat base surface of the measuring tip with the bottom of the test groove at its beginning, they report back and forth movements around the axis of the cylindrical surface of the shaft, achieving perpendicularity to the axis measuring tip to the bottom of the tested groove, record the first reading of the reading unit, which is the depth of the tested groove, move p a slider placed with the possibility of interacting with an indicator, the measuring rod of which is located perpendicular to the bisector plane of the prism, trying to touch the barrel-shaped surface of the measuring tip from one of the side surfaces of the test groove, while fixing the first primary indication of the indicator, reinstall the device on the shaft by 180 ^o , move the slider in the position that provides the ability to enter the measuring tip into the test groove, repeat the reciprocating movement of the device, upholstering perpendicularity of the axis of the probe to the bottom of the groove inspected, the slider is moved, achieving tangency barrel surface of the probe on the other side surface of the inspected groove, fixing the second primary indicator reading, determine the width of the groove inspected by the formula b = d _k + (a ₁ -a ₂ ), where b is the width of the tested groove; d _k is the largest diameter of the measuring tip; a ₁ , a ₂ - primary indicator readings; the deviation from symmetry is determined as the half-difference of the primary indicator readings, the device is removed from the shaft being tested, the slider is moved to a position that allows the measuring tip to be inserted into the tested groove, the device is mounted on the shaft, ensuring the measuring tip contacts the bottom of the tested groove at its end, and is repeated turning movements of the device, achieving the perpendicularity of the axis of the measuring tip to the bottom of the groove under test, fix the second reading of the reference unit, the deviation from the parallelism of the bottom of the test groove relative to the axis of the cylindrical surface is determined by the difference of the first and second readings of the said assembly, the slider is moved, achieving the touch of the side barrel-shaped surface of the measuring tip with the side surface of the test groove, fixing the secondary indicator reading, and the difference of the secondary and primary indicator readings, obtained by touching the measuring tip with the same side surface of the groove, determine the amount of skew of the tested for [the USSR Inventor's Certificate 1229558, IPC B 01 G 5/24, 1986 (an analogue)].

However, when measuring deviations from symmetry in this method, operations are performed associated with reinstalling the device on the shaft by 180 ^o , moving the slider to be able to enter the measuring tip into the test groove after such reinstalling the device and with repeated reciprocating movements of the device to orient it on the shaft, and before installing the device in the second position along the groove length, it is necessary to move the slider to be able to enter the measuring tip into the groove under test, which reduces the productivity method.

 The prototype is a method of measuring the parameters of the keyway of the shaft, which consists in installing the shaft with a cylindrical surface on a housing made in the form of a prism, providing contact of the measuring tip of the reading unit with the cylindrical surface of the shaft, setting the reading unit to zero, turning the shaft around the axis of the cylindrical surface, achieving contact of the measuring tip with the bottom of the groove under test at its beginning, the reciprocating motion of the shaft is reported, achieving perpendicularity measuring tip to the bottom of the test groove, record the first reading of the reading unit, which is the depth of the test groove, move the probe having side barrel-shaped surfaces and placed in a prism with the possibility of interaction with the measuring rod of the indicator fixed in the housing, achieving alternate contact of the side barrel-shaped surfaces of the mentioned probe with the lateral surfaces of the tested groove, while fixing the primary indications of the indicator, move the probe, achieving alternate contact e of lateral barrel-shaped surfaces with a measuring plane made on a prism in its bisector plane, fixing the initial indicator readings, moreover, by the difference of one primary and one initial indicator readings obtained, respectively, when touching the same lateral barrel-shaped surface of the probe with one of the side the surfaces of the test groove and the measuring plane, find the first range, by the difference of the other primary and other initial readings of the indicator, find the second range, by the floor The dimensions of the mentioned ranges are deviated from symmetry, and by their sum - the width of the tested groove, reinstall the shaft on the housing, ensuring the contact of the measuring tip with the bottom of the tested groove at its end, repeat the rotation of the shaft, achieving perpendicularity of the axis of the measuring tip to the bottom of the tested groove , fix the second reading of the reference node, determine the deviation from the parallelism of the bottom of the test groove relative to the axis of the cylindrical surface according to the difference of the first and second the testimony of the aforementioned assembly, the probe is moved, achieving contact of one of its lateral barrel-shaped surfaces with the side surface of the test groove, fixing the secondary indicator reading, and the value of the indicator shows the difference between the secondary and primary readings of the indicator obtained by touching the probe with the same side surface of the groove distortion of the tested groove [patent RU 2157508 C1, IPC G 01 B 5/24, 2000 (prototype)].

 However, when measuring deviations from the symmetry and the width of the keyway in the indicated method, it is necessary to find two initial positions of the probe achieved by moving the probe with alternate touches of its side barrel-shaped surfaces with a measuring plane made on a prism in its bisector plane, it is also necessary to fix two initial indications of the indicator, which reduces the performance of the method, and the error in finding the second initial position of the probe and fixing the second initial indicator reading below presses measurement accuracy.

Disclosure of Invention
The present invention was based on the task of developing such a method, which allows to increase its productivity and accuracy by reducing the number of operations. This is achieved by installing the shaft with a cylindrical surface on a housing made in the form of a prism, providing contact of the measuring tip of the reading unit with the cylindrical surface of the shaft, setting the reading unit to zero, turning the shaft around the axis of the cylindrical surface, achieving contact of the measuring tip with the bottom of the groove under test in at its beginning, the reciprocating motion of the shaft is reported, achieving the perpendicularity of the axis of the measuring tip to the bottom of the groove being tested, The first reading of the reading unit, which is the depth of the test groove, is moved, the probe moving with a spherical side surface and placed in the prism is able to interact with the measuring rod of the indicator fixed in the housing, achieving alternate contact of the ball-shaped side surface of the probe with the side surfaces of the test groove, fixing at primary indicators of the indicator move the probe, achieving centering of its spherical lateral surface in the prism, while fixing the initial m position of the probe is the initial indicator reading, and the first and second oscillation ranges are found respectively according to the difference between the initial reading and the corresponding primary indicator reading, the deviation from symmetry is found by the half-difference of the indicated ranges, and the width of the tested groove is determined by the sum of the ranges and the diameter of the spherical side surface of the probe, reinstall the shaft on the housing, providing the contact of the measuring tip with the bottom of the groove under test at its end, repeat the rotary motion Ala, achieving the perpendicularity of the axis of the measuring tip to the bottom of the test groove, fix the second reading of the reference node, determine the deviation from the parallelism of the bottom of the test groove relative to the axis of the cylindrical surface by the difference of the first and second readings of the said node, move the probe, achieving touch of its spherical side surface with the side surface of the tested groove, fixing the secondary indicator reading, and by the difference of the secondary and primary indicator readings obtained by touching u na with the same side surface of the groove is determined skew value verifiable groove.

 Thus, in the proposed method, in comparison with the prototype, the operation associated with finding the second initial position of the probe achieved in the prototype by moving the probe and touching its second side barrel-shaped surface with a measuring plane is excluded, and the operation of fixing the second initial indicator reading is accordingly excluded, which ensures increasing the productivity of the method as a whole, and when measuring deviations from symmetry and groove width, increasing accuracy.

Brief Description of the Drawings
Figure 1 presents the measurement scheme in this way, a General view; figure 2 - a view of figure 1.

The best embodiment of the invention
The method is implemented as follows.

The shaft 1 is based on its cylindrical surface on the working surfaces 2 and 3 of the prism 4. A reference unit 5 is fixed in this prism, the axis aa of which is aligned with the bisector plane bb of the mentioned prism. The reading unit 5 contains a measuring tip 6, which is capable of contacting either with the cylindrical surface of the shaft 1 or with the bottom of the groove under test. In the prism 4 there is a rod 7 with a probe 8 having a spherical side surface 9 with a diameter d _u and made with the possibility of basing the said surface 9 on the working surfaces 2 and 3 of the prism 4. An indicator 10 is mounted in the prism 4, which is arranged to interact with the rod 7. The longitudinal axis in-in the rod 7 is located perpendicular to the bisector plane bb prism 4.

When basing the shaft 1, the probe 6 is contacted with the cylindrical surface of the shaft and the reference unit 5 is set to zero. The shaft 1 is rotated around the axis of the cylindrical surface, achieving the approach of the measuring tip 6 into the test groove and its contact with the bottom of the groove at the beginning of the latter. Then the reciprocating motion of the shaft 1 is reported, achieving the perpendicularity of the axis aa of the reference unit 5 to the bottom of the tested groove, the first reading δ _{1 of the} reference unit 5, which is the depth of the tested groove, is fixed. Rotate the rod 7 around its longitudinal axis in-in and move it with the probe 8 along the mentioned axis, achieving successive contact of the spherical side surface 9 of the probe 8 with the side surfaces 11 and 12 of the test groove at points g ₁ and g _2, respectively, while fixing the primary readings Δ ₁ and Δ ₂ , indicator 10.

Turning and moving the rod 7, achieve simultaneous contact of the spherical side surface 9 of the probe 8 with the working surfaces 2 and 3 of the prism 4 at points g ₃ and g ₄ , fixing the initial reading Δ _{3 of the} indicator 10. The difference between the primary Δ ₁ and the original Δ _{3 of} the indicator 10 find the first swing W ₁ , i.e., W ₁ = Δ ₁ -Δ ₃ ; by the difference of the primary Δ ₂ and the initial Δ _{3 of the} readings of the indicator 10, the second range W _{2 is found} , i.e. W ₂ = Δ ₂ -Δ ₃ . By the half-difference of the mentioned ranges, a deviation from symmetry is found, i.e. Δ _sim = (W ₁ -W ₂ ) / 2, and by their sum and diameter d _{w the} spherical side surface 9 is the width of the tested groove b, i.e. b = W ₁ + W ₂ + d _u.

The shaft 1 is reinstalled in the prism 4, ensuring the contact of the measuring tip 6 with the bottom of the groove under test at its end, the reciprocating movements of the shaft 1 are repeated, achieving the axis of the reference unit 5 perpendicular to the bottom of the tested groove, the second reading δ _{2 of the} reference unit 5 is fixed, the deviation is determined from the parallelism of the bottom of the test groove relative to the axis of the cylindrical surface Δ _parallel to the difference of the first and second readings of the said node, i.e. Δ _parallel = δ ₁ -δ ₂ . Rotate the rod 7 around its longitudinal axis in-in and move it with the probe 8 along the mentioned axis, achieving contact of the spherical side surface 9 of the probe 8 with the side surface 11 of the test groove at point r ₅ , while fixing the secondary reading Δ _{4 of} indicator 10. the difference of the secondary Δ ₄ and primary Δ _{1 of the} readings of the indicator 10 obtained by touching the spherical side surface 9 of the probe 8 with the same side surface 11, determine the bias value of the tested groove Δ _bias , i.e. Δ _skew = Δ ₄ -Δ ₁ .

 Thus, when measuring deviations from the symmetry and width of the test groove, the operations of finding the second initial position of the probe and fixing the second initial indicator reading are excluded, which increases the productivity and accuracy of the method.

Industrial applicability
The method can be used at engineering enterprises with dimensional control of keyway grooves on shafts.

Claims (1)

 A method of measuring the parameters of the keyway of the shaft, namely, that the shaft is mounted on a cylindrical surface made in the form of a prism, providing contact of the measuring tip of the reading unit with the cylindrical surface of the shaft, the reading unit is set to zero, the shaft is rotated around the axis of the cylindrical surface, achieving contact measuring tip with the bottom of the groove to be checked at its beginning, the reciprocating motion of the shaft is reported, achieving axis perpendicularity the first tip to the bottom of the tested groove, the first reading of the reference unit is recorded, which is the depth of the tested groove, the probe is moved, having a side surface and placed in a prism with the possibility of interaction with the measuring rod of the indicator fixed in the housing, achieving alternate contact of the side surface of the probe with the side surfaces of the tested groove, while fixing the primary indications of the indicator, move the probe to its original position, while fixing the initial indication of the indicator, eating the first and second ranges of the indicator oscillations, finding the deviation from symmetry in the half-difference of the said ranges, determining the width of the tested groove, reinstalling the shaft on the housing, ensuring the contact of the measuring tip with the bottom of the groove being tested at its end, and repeating the rotation of the shaft, achieving perpendicularity to the measuring axis tip to the bottom of the tested groove, fix the second reading of the reference node, determine the deviation from the parallelism of the bottom of the tested groove relative to on the cylindrical surface, by the difference of the first and second readings of the said assembly, the probe is moved, achieving a touch of its side surface with the side surface of the test groove, fixing the secondary indicator reading, and by the difference of the secondary and primary readings of the indicator obtained by touching the probe with the same side the groove surface, determine the amount of skew of the tested groove, characterized in that when moving the probe, made with a spherical side surface, to the initial position, they achieve the center of the aforementioned surface in the prism, and the amplitude of the oscillations is found by the difference between the initial reading and the corresponding primary indication of the indicator, and the width of the tested groove is determined by the sum of the amplitude and diameter of the spherical side surface of the probe.

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