CA1119019A - Boring tool with a radially adjustable boring bit - Google Patents
Boring tool with a radially adjustable boring bitInfo
- Publication number
- CA1119019A CA1119019A CA000350215A CA350215A CA1119019A CA 1119019 A CA1119019 A CA 1119019A CA 000350215 A CA000350215 A CA 000350215A CA 350215 A CA350215 A CA 350215A CA 1119019 A CA1119019 A CA 1119019A
- Authority
- CA
- Canada
- Prior art keywords
- boring
- spindle
- bracket
- tool
- bit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23B—TURNING; BORING
- B23B29/00—Holders for non-rotary cutting tools; Boring bars or boring heads; Accessories for tool holders
- B23B29/03—Boring heads
- B23B29/034—Boring heads with tools moving radially, e.g. for making chamfers or undercuttings
- B23B29/03432—Boring heads with tools moving radially, e.g. for making chamfers or undercuttings radially adjustable during manufacturing
- B23B29/03457—Boring heads with tools moving radially, e.g. for making chamfers or undercuttings radially adjustable during manufacturing by pivoting the tool carriers or by elastic deformation
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Drilling And Boring (AREA)
- Cutting Tools, Boring Holders, And Turrets (AREA)
- Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
- Knives (AREA)
- Earth Drilling (AREA)
- Processing Of Stones Or Stones Resemblance Materials (AREA)
- Dowels (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A boring tool with a radially adjustable boring bit. A boring bar, supporting the boring bit is connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of rotatable machine-tool spindle. The boring bar is connected at its end facing the machine-tool spindle rigidly to a bracket. The bracket rests on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit. A
guide hole is located at least partially inside the housing cylinder and centered in the latter. A second wedge face is formed on the adjusting body, opposite the wedge face and parallel to the latter. The bracket is guided between the two wedge faces with form-closed contact.
A boring tool with a radially adjustable boring bit. A boring bar, supporting the boring bit is connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of rotatable machine-tool spindle. The boring bar is connected at its end facing the machine-tool spindle rigidly to a bracket. The bracket rests on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit. A
guide hole is located at least partially inside the housing cylinder and centered in the latter. A second wedge face is formed on the adjusting body, opposite the wedge face and parallel to the latter. The bracket is guided between the two wedge faces with form-closed contact.
Description
~ ~.9~1:9 The invention concerns a boring tool with a radially adjustable boring bit.
One such known boring tool (DE-OS 2 040 020), which is intended in particular for precision boring, has radial adjustment of the boring bit by axial movement of a pushing rod mounted in the machine-tool spindle. The front end of the pushing rod forms an adjusting body with a slightly inclined wedge face. On this wedge face rests a bracket connected to a springy, suitably supported boring bar, which mounts the boring bit.
A radial adjustment outwardly of the boring bit may be necessary in order to keep constant the diameter of a bore machined with a particular bit. For instance after a machining operation the cutting edge of the boring bit may have undergone a certain amount of wear and during the next machining operation, the bore diameter would be smaller than the specified size.
A radial adjustment inwardly of the boring bit also can be used to remove the bit from a machined surface when withdrawing it after a machining operation. This avoids any marking by the bit on the surface during with-drawal.
Finally, radial adjustment within narrow limits can also be used to produce successive bores or bore sections with slightly differing diameters. For example successive a~
~f~
l~90i9 bore sections with the same rated diameter but different tolerances.
For a bit to be useful all parts of the bit must assume a position of maximum stability after they have been adjusted. Every axial position of the pushing rod must be co-ordinated, clearly defined and have high repetition accuracy for a given, radial adjustment of the boring bar.
In the case of the above known boring tool the bracket connected to the boring bar is supported only in one direction and only on one wedge face. In this connection the spring action of torsion rods mounted on the boring bar furnish the contact force on the wedge face. In order to avoid any settling during contact on the wedge face, i.e. to ensure that the adjustment of the boring bar changes as little as possible durlng the machining process, it is necessary that the initial stressing force with which the bracket is pressed against the wedge face be made as high as possible by a suitable selection of the torsion rods. This requires very accurate guidance, as far as possible without play, of the adjusting body in its guide bore.
In the case of the known boring tool there require-ments can only be attained with great difficulty, because the guiding bore is formed by the spindle bore itself. If this bore is to be produced with sufficiently high accuracy, and if the adjusting body is to be guided with sufficiently ~019 close fit and high accuracy, the known boring tool can be used only with machine-tool spindles specially designed for this purpose.
The purpose of the invention is to design a boring tool of the type outlined that can be used with conventional rather than specially designed machine-tool spindles and nevertheless permit a very accurate adjustment of the boring bit with high repetition accuracy.
Accordingly, the invention is a boring tool with a radially adjustable boring bit, comprising: a boring bar, supporting the boring bit, connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of a rotatable machine-tool spindle; the boring bar being connected at its end facing the machine-tool spindle rigidly to a bracket; the bracket resting on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit; a guide hole located at least partially inside the housing cylinder and centred in the latter; a second wedge face formed on the adjusting body, opposite the wedge face and parallel to the latter; and the bracket being guided between the two wedge faces with form-closed contact.
The form-closed, and therefore practically play-Ul9~19 free and deformation-free, support of the bracket connected to the boring bar acts along the direct path of the force flow on the housing cylinder without requiring any guidance in the spindle bore. Thus no demands are made regarding the accuracy of the existing spindle bore. Consequently the boring tool according to the invention can be used with different machine-tool spindles without reducing the accuracy of the machining.
It was found to be of particular advantage to form the guide bore on a guiding and centering sleeve which is centred inside the housing cylinder and which can protrude with a cylindrical shoulder into a spindle bore of the machine-tool spindle, where an additional, but no essential, centering can be made. Of importance is the centering of the housing cylinder in relation to the spindle flange, which can be made on a short centering cylinder usually present on machine-tool spindles of this type.
The invention is illustrated, by way of example, in the drawings in which:
Figure 1 is a boring tool in longitudinal section, mounted on a machine-tool spindle, Figure 2 is a view in direction of the arrow II-II
in Figure 1, in which the boring bar is omitted, and Figure 3 is a section along the line III-III in Figure 1.
~i~9019 A boring bar 1, which mounts a boring bit 2, is connected to a supporting ring 4. The ring 4 is connected to a housing cylinder 5 via two torsion rods 3 mounted transversely to the longitudinal axis of the boring bar 1.
The housing cylinder 5 is screwed to a flange ring 6 which, with the insertion of a flange 7, is screwed to a spindle flange 8 of a machine-tool spindle 9 having a spindle bore 10 .
The boring bar 1 is connected rigidly to a bracket 11 at its end facing the machine-tool spindle, whereby the boring bar 1 and/or bracket 11 can be screwed together with a plate 3' located between the two torsion rods 3 and whereby the plate 3' can form a single piece with the torsion rods 3 and supporting ring 4. For this purpose approximately semi~circular slots 12 can be milled in a disc-shaped blank.
Near its free end the bracket 11 carries on opposing sides two sliding bodies 13. These bodies 13 allows the bracket 11 to rest on a first wedge face 14 located on the same side as the drilling bit 2, and on a second wedge face 15 which faces the wedge face 14. Face 15 is parallel to face 14. The two wedge faces 14, 15 are formed on a forked adjusting body 16 and are inclined at a slight angle of approximately 1 to 2, relative to the longitudinal axis of the spindle.
11~9019 With its cylindrical outside face the adjusting body is guided in a guide bore 17 in a guiding and centering sleeve 18, which is centered in an internal bore 19 of the housing cylinder 5. The guiding and centering sleeve 18 is connected as one single piece to the flange 7 and a cylindrical shoulder 20. Shoulder 20 protrudes into the spindle bore 10 where it can also be centered if the spindle bore is machined with sufficient accuracy.
A fitting key 21 attached to the adjusting body 16 is guided in a keyway 22 of the cylindrical shoulder 20 and prevents any rotation of the adjusting body 16, relative to the guiding and centering sleeve 18.
A pushing rod 23 mounted in the spindle bore 10 is connected to the adjusting body 16. The bracket 11 is supported on the wedge faces 14 and 15 in a zone located outside the spindle bore 10 and largely inside the housing cylinder 5 and the sleeve 18 connected to it.
By an axial adjustment of the pushing rod 23 releasably attached to the adjusting body 16, the bracket 11 is shifted radially by the slightly inclined wedge faces 14 and 15 in such a way that the free end of the boring bar 1 which carries the boring bit 2 is displaced radially in the opposite direction. The torsion rods 3 provide the support for this movement.
- The boring tool, as a unit, can be unscrewed from ~1190~9 the spindle flange 8, whereby the adjusting body 16 is detached likewise from the pushing rod 23.
In the practical example shown in the drawing, the boring bar 1 is connected exchangably to the plate 3', which in turn is machined in one piece with the bracket 11.
One such known boring tool (DE-OS 2 040 020), which is intended in particular for precision boring, has radial adjustment of the boring bit by axial movement of a pushing rod mounted in the machine-tool spindle. The front end of the pushing rod forms an adjusting body with a slightly inclined wedge face. On this wedge face rests a bracket connected to a springy, suitably supported boring bar, which mounts the boring bit.
A radial adjustment outwardly of the boring bit may be necessary in order to keep constant the diameter of a bore machined with a particular bit. For instance after a machining operation the cutting edge of the boring bit may have undergone a certain amount of wear and during the next machining operation, the bore diameter would be smaller than the specified size.
A radial adjustment inwardly of the boring bit also can be used to remove the bit from a machined surface when withdrawing it after a machining operation. This avoids any marking by the bit on the surface during with-drawal.
Finally, radial adjustment within narrow limits can also be used to produce successive bores or bore sections with slightly differing diameters. For example successive a~
~f~
l~90i9 bore sections with the same rated diameter but different tolerances.
For a bit to be useful all parts of the bit must assume a position of maximum stability after they have been adjusted. Every axial position of the pushing rod must be co-ordinated, clearly defined and have high repetition accuracy for a given, radial adjustment of the boring bar.
In the case of the above known boring tool the bracket connected to the boring bar is supported only in one direction and only on one wedge face. In this connection the spring action of torsion rods mounted on the boring bar furnish the contact force on the wedge face. In order to avoid any settling during contact on the wedge face, i.e. to ensure that the adjustment of the boring bar changes as little as possible durlng the machining process, it is necessary that the initial stressing force with which the bracket is pressed against the wedge face be made as high as possible by a suitable selection of the torsion rods. This requires very accurate guidance, as far as possible without play, of the adjusting body in its guide bore.
In the case of the known boring tool there require-ments can only be attained with great difficulty, because the guiding bore is formed by the spindle bore itself. If this bore is to be produced with sufficiently high accuracy, and if the adjusting body is to be guided with sufficiently ~019 close fit and high accuracy, the known boring tool can be used only with machine-tool spindles specially designed for this purpose.
The purpose of the invention is to design a boring tool of the type outlined that can be used with conventional rather than specially designed machine-tool spindles and nevertheless permit a very accurate adjustment of the boring bit with high repetition accuracy.
Accordingly, the invention is a boring tool with a radially adjustable boring bit, comprising: a boring bar, supporting the boring bit, connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of a rotatable machine-tool spindle; the boring bar being connected at its end facing the machine-tool spindle rigidly to a bracket; the bracket resting on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit; a guide hole located at least partially inside the housing cylinder and centred in the latter; a second wedge face formed on the adjusting body, opposite the wedge face and parallel to the latter; and the bracket being guided between the two wedge faces with form-closed contact.
The form-closed, and therefore practically play-Ul9~19 free and deformation-free, support of the bracket connected to the boring bar acts along the direct path of the force flow on the housing cylinder without requiring any guidance in the spindle bore. Thus no demands are made regarding the accuracy of the existing spindle bore. Consequently the boring tool according to the invention can be used with different machine-tool spindles without reducing the accuracy of the machining.
It was found to be of particular advantage to form the guide bore on a guiding and centering sleeve which is centred inside the housing cylinder and which can protrude with a cylindrical shoulder into a spindle bore of the machine-tool spindle, where an additional, but no essential, centering can be made. Of importance is the centering of the housing cylinder in relation to the spindle flange, which can be made on a short centering cylinder usually present on machine-tool spindles of this type.
The invention is illustrated, by way of example, in the drawings in which:
Figure 1 is a boring tool in longitudinal section, mounted on a machine-tool spindle, Figure 2 is a view in direction of the arrow II-II
in Figure 1, in which the boring bar is omitted, and Figure 3 is a section along the line III-III in Figure 1.
~i~9019 A boring bar 1, which mounts a boring bit 2, is connected to a supporting ring 4. The ring 4 is connected to a housing cylinder 5 via two torsion rods 3 mounted transversely to the longitudinal axis of the boring bar 1.
The housing cylinder 5 is screwed to a flange ring 6 which, with the insertion of a flange 7, is screwed to a spindle flange 8 of a machine-tool spindle 9 having a spindle bore 10 .
The boring bar 1 is connected rigidly to a bracket 11 at its end facing the machine-tool spindle, whereby the boring bar 1 and/or bracket 11 can be screwed together with a plate 3' located between the two torsion rods 3 and whereby the plate 3' can form a single piece with the torsion rods 3 and supporting ring 4. For this purpose approximately semi~circular slots 12 can be milled in a disc-shaped blank.
Near its free end the bracket 11 carries on opposing sides two sliding bodies 13. These bodies 13 allows the bracket 11 to rest on a first wedge face 14 located on the same side as the drilling bit 2, and on a second wedge face 15 which faces the wedge face 14. Face 15 is parallel to face 14. The two wedge faces 14, 15 are formed on a forked adjusting body 16 and are inclined at a slight angle of approximately 1 to 2, relative to the longitudinal axis of the spindle.
11~9019 With its cylindrical outside face the adjusting body is guided in a guide bore 17 in a guiding and centering sleeve 18, which is centered in an internal bore 19 of the housing cylinder 5. The guiding and centering sleeve 18 is connected as one single piece to the flange 7 and a cylindrical shoulder 20. Shoulder 20 protrudes into the spindle bore 10 where it can also be centered if the spindle bore is machined with sufficient accuracy.
A fitting key 21 attached to the adjusting body 16 is guided in a keyway 22 of the cylindrical shoulder 20 and prevents any rotation of the adjusting body 16, relative to the guiding and centering sleeve 18.
A pushing rod 23 mounted in the spindle bore 10 is connected to the adjusting body 16. The bracket 11 is supported on the wedge faces 14 and 15 in a zone located outside the spindle bore 10 and largely inside the housing cylinder 5 and the sleeve 18 connected to it.
By an axial adjustment of the pushing rod 23 releasably attached to the adjusting body 16, the bracket 11 is shifted radially by the slightly inclined wedge faces 14 and 15 in such a way that the free end of the boring bar 1 which carries the boring bit 2 is displaced radially in the opposite direction. The torsion rods 3 provide the support for this movement.
- The boring tool, as a unit, can be unscrewed from ~1190~9 the spindle flange 8, whereby the adjusting body 16 is detached likewise from the pushing rod 23.
In the practical example shown in the drawing, the boring bar 1 is connected exchangably to the plate 3', which in turn is machined in one piece with the bracket 11.
Claims (7)
1. A boring tool with a radially adjustable boring bit, comprising:
a boring bar, supporting the boring bit, connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of rotatable machine-tool spindle;
the boring bar being connected at its end facing the machine-tool spindle rigidly to a bracket;
the bracket resting on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit;
a guide hole located at least partially inside the housing cylinder and centered in the latter;
a second wedge face formed on the adjusting body, opposite the wedge face and parallel to the latter; and the bracket being guided between the two wedge faces with form-closed contact.
a boring bar, supporting the boring bit, connected via torsion rods arranged transversely to its longitudinal axis to a supporting ring which can be mounted via a housing cylinder on a spindle flange of rotatable machine-tool spindle;
the boring bar being connected at its end facing the machine-tool spindle rigidly to a bracket;
the bracket resting on a slightly inclined wedge face of an adjusting body guided in a guide hole, movable axially by means of a pushing rod for a radial adjustment of the boring bit;
a guide hole located at least partially inside the housing cylinder and centered in the latter;
a second wedge face formed on the adjusting body, opposite the wedge face and parallel to the latter; and the bracket being guided between the two wedge faces with form-closed contact.
2. A boring tool according to claim 1, in which the guide hole is formed on a guiding and centering sleeve centered in the housing cylinder and projecting with a cylindrical shoulder into a spindle bore of the machine-tool spindle.
3. A boring tool according to claim 2, in which the guiding and centering sleeve is centered on the machine-tool spindle.
4. A boring tool according to claim 2 and 3 in which the guiding and centering sleeve has a flange which connects the housing cylinder and a flange linked to the latter to the spindle flange.
5. A boring tool according to claim 1, in which the adjusting body is guided non-rotatably longitudinally in the guiding hole.
6. A boring tool according to claim 1, in which the adjustint body is mounted detachably on the pushing rod.
7. A boring tool according to claim 1, in which the boring bar is mounted detachably on a plate connected to the torsion rods.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2915976A DE2915976C2 (en) | 1979-04-20 | 1979-04-20 | Drill head |
| DEP2915976.0 | 1979-04-20 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1119019A true CA1119019A (en) | 1982-03-02 |
Family
ID=6068795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000350215A Expired CA1119019A (en) | 1979-04-20 | 1980-04-18 | Boring tool with a radially adjustable boring bit |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0017967B1 (en) |
| JP (1) | JPH0112603B2 (en) |
| AT (1) | ATE1333T1 (en) |
| BR (1) | BR8008175A (en) |
| CA (1) | CA1119019A (en) |
| DE (2) | DE7911572U1 (en) |
| ES (1) | ES490660A0 (en) |
| MX (1) | MX149646A (en) |
| WO (1) | WO1980002243A1 (en) |
| ZA (1) | ZA802348B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4015509C1 (en) * | 1990-05-15 | 1991-07-11 | Bauer, Walter, Dr.-Ing., 7403 Ammerbuch, De | Tool holder for machine tool - has base with rotating inertia weight to drive it |
| DE19908905C2 (en) | 1999-03-02 | 2003-03-20 | Daimler Chrysler Ag | Fuel cell system with associated hydrogen production plant |
| CN104289743B (en) * | 2013-07-17 | 2018-05-25 | 株式会社神崎高级工机制作所 | Device for boring |
| WO2015181153A1 (en) * | 2014-05-26 | 2015-12-03 | Mauser-Werke Oberndorf Maschinenbau Gmbh | Fine-hole drill head system |
| CN111646094B (en) * | 2019-12-31 | 2021-06-11 | 安吉致通五金制品有限公司 | Full-automatic unloading material feeding unit manages in side |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE444336A (en) * | ||||
| US2816767A (en) * | 1953-08-10 | 1957-12-17 | New Britain Machine Co | Tool holder |
| US3296898A (en) * | 1965-03-15 | 1967-01-10 | Gen Motors Corp | Retractable boring bar |
| DE2040020A1 (en) * | 1970-08-12 | 1972-02-17 | Ludwigsburger Maschb Gmbh | Drilling unit, especially for performing fine drilling work |
-
1979
- 1979-04-20 DE DE19797911572U patent/DE7911572U1/en not_active Expired
- 1979-04-20 DE DE2915976A patent/DE2915976C2/en not_active Expired
-
1980
- 1980-04-16 WO PCT/DE1980/000050 patent/WO1980002243A1/en unknown
- 1980-04-16 AT AT80102030T patent/ATE1333T1/en not_active IP Right Cessation
- 1980-04-16 BR BR8008175A patent/BR8008175A/en unknown
- 1980-04-16 JP JP55500853A patent/JPH0112603B2/ja not_active Expired
- 1980-04-16 EP EP80102030A patent/EP0017967B1/en not_active Expired
- 1980-04-17 ES ES490660A patent/ES490660A0/en active Granted
- 1980-04-18 CA CA000350215A patent/CA1119019A/en not_active Expired
- 1980-04-18 ZA ZA00802348A patent/ZA802348B/en unknown
- 1980-04-21 MX MX182039A patent/MX149646A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| ZA802348B (en) | 1981-05-27 |
| JPS56500406A (en) | 1981-04-02 |
| MX149646A (en) | 1983-12-07 |
| EP0017967A1 (en) | 1980-10-29 |
| DE2915976A1 (en) | 1980-10-30 |
| WO1980002243A1 (en) | 1980-10-30 |
| ES8100772A1 (en) | 1980-12-01 |
| ES490660A0 (en) | 1980-12-01 |
| DE7911572U1 (en) | 1982-04-08 |
| ATE1333T1 (en) | 1982-07-15 |
| JPH0112603B2 (en) | 1989-03-01 |
| BR8008175A (en) | 1981-03-31 |
| EP0017967B1 (en) | 1982-07-14 |
| DE2915976C2 (en) | 1983-11-03 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |