INVOLUTE GRINDING WHEEL DRESSER
United States Patent 3815569
An involute grinding wheel dresser comprising a base and an arm pivotally mounted on said base for movement about a pivotal axis. A slide is mounted on the arm by anti-friction means for movement transversely of the arm. A dressing tool is mounted on the slide and interengaging means are provided between the base and the slide and are operable to limit movement of the slide with respect to the arm, as the arm is swung about the pivotal axis, in a direction such that the tool moves radially outwardly as well as tangentially to define an involute curve.
US Patent References:
Apparatus for shaping the millstones for rectifying gear teeth
Voignier - October 1932 - 1880612
Device for dressing grinding wheels
Shotey - June 1933 - 1912410
Involute form dresser
Peters - July 1949 - 2476322
Grinding wheel dressing device
Alderman - May 1953 - 2637312
Apparatus for shaping the millstones for rectifying gear teeth
Voignier - October 1932 - 1880612
Device for dressing grinding wheels
Shotey - June 1933 - 1912410
Involute form dresser
Peters - July 1949 - 2476322
Grinding wheel dressing device
Alderman - May 1953 - 2637312
Application Number:
05/278290
Publication Date:
06/11/1974
Filing Date:
08/07/1972
View Patent Images:
Export Citation:
Primary Class:
International Classes:
B24B53/075; B24B53/06; B24B53/08
Field of Search:
125/11,11T
Primary Examiner:
Whitehead, Harold D.
Attorney, Agent or Firm:
Barnes, Kisselle, Raisch & Choate
Claims:
I claim
1. In an involute grinding wheel dresser, the combination comprising
2. The combination set forth in claim 1 wherein said guide member comprises a guide roller on one of said slide and said base rotatably mounted about an axis parallel to the axis of the slide.
3. The combination set forth in claim 2 wherein said surface is made of a relatively deformable material whereby said guide roller frictionally engages and rolls with respect to said surface.
4. The combination set forth in claim 3 wherein said surface is defined by a plate on said base.
5. The combination set forth in claim 1 wherein the axis of the roller and the point of the tool lie in a plane tangent to the base cylindrical diameter of the involute.
6. The combination set forth in claim 1 including anti-friction means between the slide and the arm.
7. The combination set forth in claim 1 wherein said base comprises an upright portion,
8. The combination set forth in claim 1 including means for angularly adjusting the relationship of said slide with respect to said arm.
9. The combination set forth in claim 1 wherein said arm supports a slideway for said slide,
10. In an involute grinding wheel dresser, the combination comprising
11. The combination set forth in claim 12 wherein said surface is made of relatively deformable material whereby said guide rollers frictionally engage and roll with respect to said surface.
12. The combination set forth in claim 12 wherein said base comprises an upright portion,
13. The combination set forth in claim 12 including means for angularly adjusting the relationship of said slide with respect to said arm.
14. The combination set forth in claim 10 including means for locking said arm with respect to said base.
15. The combination set forth in claim 10 including means for selectively restricting the direction in which the arm may be swung.
1. In an involute grinding wheel dresser, the combination comprising
2. The combination set forth in claim 1 wherein said guide member comprises a guide roller on one of said slide and said base rotatably mounted about an axis parallel to the axis of the slide.
3. The combination set forth in claim 2 wherein said surface is made of a relatively deformable material whereby said guide roller frictionally engages and rolls with respect to said surface.
4. The combination set forth in claim 3 wherein said surface is defined by a plate on said base.
5. The combination set forth in claim 1 wherein the axis of the roller and the point of the tool lie in a plane tangent to the base cylindrical diameter of the involute.
6. The combination set forth in claim 1 including anti-friction means between the slide and the arm.
7. The combination set forth in claim 1 wherein said base comprises an upright portion,
8. The combination set forth in claim 1 including means for angularly adjusting the relationship of said slide with respect to said arm.
9. The combination set forth in claim 1 wherein said arm supports a slideway for said slide,
10. In an involute grinding wheel dresser, the combination comprising
11. The combination set forth in claim 12 wherein said surface is made of relatively deformable material whereby said guide rollers frictionally engage and roll with respect to said surface.
12. The combination set forth in claim 12 wherein said base comprises an upright portion,
13. The combination set forth in claim 12 including means for angularly adjusting the relationship of said slide with respect to said arm.
14. The combination set forth in claim 10 including means for locking said arm with respect to said base.
15. The combination set forth in claim 10 including means for selectively restricting the direction in which the arm may be swung.
Description:
This invention relates to involute grinding wheel dressers.
BACKGROUND OF THE INVENTION
In the production of involute splines and gear teeth, one method that is commonly used is to utilize a grinding wheel which has the periphery thereof formed and dressed to the shape of the space between two adjacent involute teeth. In use, the grinding wheel wears and it is necessary to utilize a diamond tool mounted in an appropriate device to dress and redress the periphery of the grinding wheel.
Various devices have heretofore been suggested for dressing the grinding wheel and these function in various manners and have differing degrees of accuracy. Among the most common types are those that utilize cams or discs for the base diameter of each involute curve. Such devices have the disadvantage in that they often require various cams or discs or similar parts to be replaced for each size of tooth or wheel being dressed.
Among the objects of the invention are to provide an improved involute grinding wheel dresser which obviates the need for replaceable cams or discs; which can be utilized for variable spaced diameters from zero diameter to maximum base diameter of a particular dresser; wherein variable space adjustment between teeth is readily achieved; wherein all settings can be made with a set of standard gauge blocks; wherein both sides of a grinding wheel can be dressed without any change in settings; wherein once the device is oriented with the work, no further re-orientation is required if the sixe of the work changes; wherein the entire device is arranged so that it is not adversely affected by the environment in which it is used.
SUMMARY OF THE INVENTION
The involute grinding wheel dresser embodying the invention, the combination comprising a base, an arm pivotally mounted on said base for movement about a pivotal axis and a slide mounted on the arm by anti-friction means for movement transversely of the arm. A dressing tool is supported on the slide and interengaging means are provided between the base and the slide and are operable to limit movement of the slide with respect to the arm, as the arm is swung about the pivotal axis, in a direction such that the tool moves radially outwardly as well as tangentially to define an involute curve.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary side elevational view of an involute grinding wheel dresser embodying the invention.
FIG. 2 is a fragmentary diagram showing the manner in which the dresser functions to dress the grinding wheel.
FIG. 3 is an end view taken from the right of FIG. 1.
FIG. 4 is a fragmentary sectional view taken along the line 4--4 in FIG. 1.
FIG. 5 is a fragmentary end view taken from the left of FIG. 1.
FIG. 6 is a fragmentary sectional view taken along the line 6--6 in FIG. 1, showing the parts in a different operative position.
FIG. 7 is a sectional view taken along the line 7--7 in FIG. 1.
DESCRIPTION
The involute grinding wheel dresser embodying the invention utilizes mechanical parts to represent the fundamental components of an involute curve which are the radius of the base diameter, the tangent to the base diameter, and the movement of the tool or point from the point of tangency to a selected point which changes uniformly an amount equal to the length of the arc of the base circle about which the tangent is rotated.
Referring to FIG. 2 which shows a fragment of the grinding wheel G, the periphery is intended to be dressed in such a manner that a dressing tool moves from the base diameter B at a point of tangency T along an arc A to dress the wheel.
Referring to FIG. 1, the involute grinding wheel dresser embodying the invention comprises a base 10 including a base plate 11 adapted to be fixed to the bed of a machine or the like by bolts 12. The base 10 further includes spaced uprights 13, 14. An arm 15 is pivoted to the upright 13 by a pin 16 around a pivotal axis P. Arm 15 adjustably supports, as presently described, a slideway 17 on which a slide 18 is mounted by anti-friction means such as ball bearings 19 functioning in grooves in the slide 18 and slideway 17.
A support 20 is fixed to the slide 28 and comprises a first portion or leg 21 that has a surface 22 engaging surface 23 of upright 14, a base 24, and a second portion or leg 25 that extends downwardly along the opposite surface 26 of upright 14 (FIG. 1). A pair of hardened metal rollers 27 are rotatably mounted by needle bearings 28 on a shaft 29 in the lower portion of leg 25 (FIG. 4). The periphery of each guide roller is such that it engages a plate 30 on the side 26 of upright 14 (FIG. 1). The plate 30 is of predetermined hardness so that as the upright is pressed against the rollers 27 by the compressive force tending to spread the uprights 13, 14, the guide roller 27 tends to deform the surface of plate 30 providing high friction between the guide rollers 27 and the plate 30.
A tool holder support 31 is rotatably mounted on the lower end of the leg 21 and retained by plate 31a. The tool holder support 31 includes spring loaded detent balls 33 engaging indentations 34 for approximating any indexed position of the tool for dressing the two sides of the periphery of the grinding wheel. A lock pin 36 is adapted to engage one of two openings 37 to lock the tool holder in indexed position. Tool holder support 31 further includes a tool holder 35 slidably mounted and retained by bolt 32. Tool holder 35 supports the tool T with its point aligned with the axis of rotation of the tool holder support 31.
As shown in FIGS. 1 and 3, retractable pins 40 are provided for holding the arm 15 in upright position. When it is desired to utilize the dresser, as presently described, one or the other of the pins 40 is retracted to permit swinging movement of the arm 15.
The slideway 17 is adapted to be angularly adjusted for reasons presently described and, accordingly, the slideway 17 is fixed on a pin 41 which extends into and is rotatable with respect to a block 42 fixed to the arm 15 (FIG. 7). Screws 43 are threaded into the block 42 and engage pins 44 on the slideway 17 that extend into slots 45 in the block. The screws are threaded equally outwardly to provide equal angular positions of the slideway 17 about the center with respect to the block 42. Nuts 46 lock the screws in adjusted position. Screw 48 locks the slideway 17 on either side of center.
As a further safeguard to prevent movement when the dresser is being set up or is not in use, a lock pin 47 extends through the slide 18 into an opening in the slideway 17 (FIG. 1).
In use, the axis of rotation of the arm 15 is brought into alignment with the axis of the work piece (FIG. 1). The distance between this axis and the axis of the diamond tool T, which are in parallel planes, parallel to the plane of the base surface, is set to the radius of the base diameter of the involute. The method of setting this distance is indirectly controlled by the relationship between component parts of the dresser and is made by using measuring blocks between the base 11 and the block 42 on the arm 15.
The dresser is designed so that the axis of the diamond tool T intersects the axis of rotation of the slideway 17 through pin 41 and is parallel to the direction of travel of the slideway 17. The symmetry and the thickness of the grinding wheel may be controlled by positioning the point of the diamond tool T a predetermined distance from the axis of rotation of the slideway 17. The method of setting this distance is indirectly controlled by the relationship between components parts of the dresser and is made by using measuring blocks between the tool holder 35 and a pin in the tool holder support 31.
The dresser is then brought into position near the grinding wheel and the wheel is moved toward the diamond tool T. As the wheel is moved toward the dresser one pin 40 is retracted and arm 15 is swung to one side to dress one side of the wheel; when a sufficient amount of involute has been formed the pin is re-engaged, the grinding wheel is moved away and the diamond tool T is indexed to the other side of the wheel. Retracting the other pin 40 again the wheel is moved toward the dresser and the arm 15 is swung to the other side to dress the other side. The position of the wheel is controlled to be identical for the final dress on both sides of the wheel to provide the required symmetry.
The axis of the guide wheels 27 lies in a plane tangent to the base cylindrical diameter of the involute. The perpendicular diameter from this axis to the axis P of the rotation of the arm 15 corresponds to the radius of the base diameter. The plane containing the periphery of the guide wheels 27 is at right angles to the travel of the beam slide 18. As the arm 15 is moved about its pivot axis P the slide 18 is moved with respect to slideway 17 an amount equal to the arc of rotation of the radius of the base diameter. Since the radial distance from the pivot axis P of the arm 15 to the contact point of the guide wheels 27 (as viewed from the plane of rotation of the arm 15) is increasing, the slide 18 has to move in the direction which the guide wheels 27 may roll. The curve described by the guide wheels 27 is an involute of this diameter. The axis of the diamond tool T and the axis of the guide wheels 27 are parallel and in the same plane which is parallel to the pivot axis P of the arm 15. Therefore the point of the diamond tool T describes an involute curve of the same base diameter on the grinding wheel.
The usual angle of rotation of the slideway 17 is zero degrees. However, when the width of the tooth space to be ground is so large as to cause the diamond tool T to start dressing at an unacceptable distance from the base diameter, it becomes necessary to increase the angle of rotation by tilting the slideway 17 by adjusting screws 43 (FIG. 7) symmetrically about the center.
BACKGROUND OF THE INVENTION
In the production of involute splines and gear teeth, one method that is commonly used is to utilize a grinding wheel which has the periphery thereof formed and dressed to the shape of the space between two adjacent involute teeth. In use, the grinding wheel wears and it is necessary to utilize a diamond tool mounted in an appropriate device to dress and redress the periphery of the grinding wheel.
Various devices have heretofore been suggested for dressing the grinding wheel and these function in various manners and have differing degrees of accuracy. Among the most common types are those that utilize cams or discs for the base diameter of each involute curve. Such devices have the disadvantage in that they often require various cams or discs or similar parts to be replaced for each size of tooth or wheel being dressed.
Among the objects of the invention are to provide an improved involute grinding wheel dresser which obviates the need for replaceable cams or discs; which can be utilized for variable spaced diameters from zero diameter to maximum base diameter of a particular dresser; wherein variable space adjustment between teeth is readily achieved; wherein all settings can be made with a set of standard gauge blocks; wherein both sides of a grinding wheel can be dressed without any change in settings; wherein once the device is oriented with the work, no further re-orientation is required if the sixe of the work changes; wherein the entire device is arranged so that it is not adversely affected by the environment in which it is used.
SUMMARY OF THE INVENTION
The involute grinding wheel dresser embodying the invention, the combination comprising a base, an arm pivotally mounted on said base for movement about a pivotal axis and a slide mounted on the arm by anti-friction means for movement transversely of the arm. A dressing tool is supported on the slide and interengaging means are provided between the base and the slide and are operable to limit movement of the slide with respect to the arm, as the arm is swung about the pivotal axis, in a direction such that the tool moves radially outwardly as well as tangentially to define an involute curve.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary side elevational view of an involute grinding wheel dresser embodying the invention.
FIG. 2 is a fragmentary diagram showing the manner in which the dresser functions to dress the grinding wheel.
FIG. 3 is an end view taken from the right of FIG. 1.
FIG. 4 is a fragmentary sectional view taken along the line 4--4 in FIG. 1.
FIG. 5 is a fragmentary end view taken from the left of FIG. 1.
FIG. 6 is a fragmentary sectional view taken along the line 6--6 in FIG. 1, showing the parts in a different operative position.
FIG. 7 is a sectional view taken along the line 7--7 in FIG. 1.
DESCRIPTION
The involute grinding wheel dresser embodying the invention utilizes mechanical parts to represent the fundamental components of an involute curve which are the radius of the base diameter, the tangent to the base diameter, and the movement of the tool or point from the point of tangency to a selected point which changes uniformly an amount equal to the length of the arc of the base circle about which the tangent is rotated.
Referring to FIG. 2 which shows a fragment of the grinding wheel G, the periphery is intended to be dressed in such a manner that a dressing tool moves from the base diameter B at a point of tangency T along an arc A to dress the wheel.
Referring to FIG. 1, the involute grinding wheel dresser embodying the invention comprises a base 10 including a base plate 11 adapted to be fixed to the bed of a machine or the like by bolts 12. The base 10 further includes spaced uprights 13, 14. An arm 15 is pivoted to the upright 13 by a pin 16 around a pivotal axis P. Arm 15 adjustably supports, as presently described, a slideway 17 on which a slide 18 is mounted by anti-friction means such as ball bearings 19 functioning in grooves in the slide 18 and slideway 17.
A support 20 is fixed to the slide 28 and comprises a first portion or leg 21 that has a surface 22 engaging surface 23 of upright 14, a base 24, and a second portion or leg 25 that extends downwardly along the opposite surface 26 of upright 14 (FIG. 1). A pair of hardened metal rollers 27 are rotatably mounted by needle bearings 28 on a shaft 29 in the lower portion of leg 25 (FIG. 4). The periphery of each guide roller is such that it engages a plate 30 on the side 26 of upright 14 (FIG. 1). The plate 30 is of predetermined hardness so that as the upright is pressed against the rollers 27 by the compressive force tending to spread the uprights 13, 14, the guide roller 27 tends to deform the surface of plate 30 providing high friction between the guide rollers 27 and the plate 30.
A tool holder support 31 is rotatably mounted on the lower end of the leg 21 and retained by plate 31a. The tool holder support 31 includes spring loaded detent balls 33 engaging indentations 34 for approximating any indexed position of the tool for dressing the two sides of the periphery of the grinding wheel. A lock pin 36 is adapted to engage one of two openings 37 to lock the tool holder in indexed position. Tool holder support 31 further includes a tool holder 35 slidably mounted and retained by bolt 32. Tool holder 35 supports the tool T with its point aligned with the axis of rotation of the tool holder support 31.
As shown in FIGS. 1 and 3, retractable pins 40 are provided for holding the arm 15 in upright position. When it is desired to utilize the dresser, as presently described, one or the other of the pins 40 is retracted to permit swinging movement of the arm 15.
The slideway 17 is adapted to be angularly adjusted for reasons presently described and, accordingly, the slideway 17 is fixed on a pin 41 which extends into and is rotatable with respect to a block 42 fixed to the arm 15 (FIG. 7). Screws 43 are threaded into the block 42 and engage pins 44 on the slideway 17 that extend into slots 45 in the block. The screws are threaded equally outwardly to provide equal angular positions of the slideway 17 about the center with respect to the block 42. Nuts 46 lock the screws in adjusted position. Screw 48 locks the slideway 17 on either side of center.
As a further safeguard to prevent movement when the dresser is being set up or is not in use, a lock pin 47 extends through the slide 18 into an opening in the slideway 17 (FIG. 1).
In use, the axis of rotation of the arm 15 is brought into alignment with the axis of the work piece (FIG. 1). The distance between this axis and the axis of the diamond tool T, which are in parallel planes, parallel to the plane of the base surface, is set to the radius of the base diameter of the involute. The method of setting this distance is indirectly controlled by the relationship between component parts of the dresser and is made by using measuring blocks between the base 11 and the block 42 on the arm 15.
The dresser is designed so that the axis of the diamond tool T intersects the axis of rotation of the slideway 17 through pin 41 and is parallel to the direction of travel of the slideway 17. The symmetry and the thickness of the grinding wheel may be controlled by positioning the point of the diamond tool T a predetermined distance from the axis of rotation of the slideway 17. The method of setting this distance is indirectly controlled by the relationship between components parts of the dresser and is made by using measuring blocks between the tool holder 35 and a pin in the tool holder support 31.
The dresser is then brought into position near the grinding wheel and the wheel is moved toward the diamond tool T. As the wheel is moved toward the dresser one pin 40 is retracted and arm 15 is swung to one side to dress one side of the wheel; when a sufficient amount of involute has been formed the pin is re-engaged, the grinding wheel is moved away and the diamond tool T is indexed to the other side of the wheel. Retracting the other pin 40 again the wheel is moved toward the dresser and the arm 15 is swung to the other side to dress the other side. The position of the wheel is controlled to be identical for the final dress on both sides of the wheel to provide the required symmetry.
The axis of the guide wheels 27 lies in a plane tangent to the base cylindrical diameter of the involute. The perpendicular diameter from this axis to the axis P of the rotation of the arm 15 corresponds to the radius of the base diameter. The plane containing the periphery of the guide wheels 27 is at right angles to the travel of the beam slide 18. As the arm 15 is moved about its pivot axis P the slide 18 is moved with respect to slideway 17 an amount equal to the arc of rotation of the radius of the base diameter. Since the radial distance from the pivot axis P of the arm 15 to the contact point of the guide wheels 27 (as viewed from the plane of rotation of the arm 15) is increasing, the slide 18 has to move in the direction which the guide wheels 27 may roll. The curve described by the guide wheels 27 is an involute of this diameter. The axis of the diamond tool T and the axis of the guide wheels 27 are parallel and in the same plane which is parallel to the pivot axis P of the arm 15. Therefore the point of the diamond tool T describes an involute curve of the same base diameter on the grinding wheel.
The usual angle of rotation of the slideway 17 is zero degrees. However, when the width of the tooth space to be ground is so large as to cause the diamond tool T to start dressing at an unacceptable distance from the base diameter, it becomes necessary to increase the angle of rotation by tilting the slideway 17 by adjusting screws 43 (FIG. 7) symmetrically about the center.