US1187992A - Cylinder-reboring device. - Google Patents
Cylinder-reboring device. Download PDFInfo
- Publication number
- US1187992A US1187992A US3010515A US3010515A US1187992A US 1187992 A US1187992 A US 1187992A US 3010515 A US3010515 A US 3010515A US 3010515 A US3010515 A US 3010515A US 1187992 A US1187992 A US 1187992A
- Authority
- US
- United States
- Prior art keywords
- shaft
- cylinder
- nut
- screw
- tool
- 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 - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
- B23Q9/00—Arrangements for supporting or guiding portable metal-working machines or apparatus
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S408/00—Cutting by use of rotating axially moving tool
- Y10S408/709—Reboring piston receiving cylinder
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T408/00—Cutting by use of rotating axially moving tool
- Y10T408/55—Cutting by use of rotating axially moving tool with work-engaging structure other than Tool or tool-support
- Y10T408/561—Having tool-opposing, work-engaging surface
- Y10T408/5621—Connected to Tool through opening being enlarged by Tool
- Y10T408/5622—Plural, coaxially opposing, work-engaging means
Definitions
- This invention relates to devices for use in metal-working, and particularly totools and operating means therefor for truing out cylinders, such as engine cylinders, for
- Patent No. 1,097,318 which was issued 'to me on May 19, 1914, and the present invention relates. to improvements over the machine of that patent.
- One object in view is to provide means for properly centering the toolconstruction and combinations of parts as carrying means within the cylinder, together with an improved bearing constructionfor the tool-carrying shaft, and also afeed arrangementfor said shaft whereby thelatter may be quickly removed at'the end of each operation.
- FIG. 1 is a perspec .tive view' of the device
- Fig. 2 is a longi- 'tudinal sectional View of the same, illustrating the device in working relation to a .blocks inoperative position
- Fig. 3 is a sec I tion on the line "IIIIII of Fig. 2 (on a larger scale)
- Fig. 4 is a View in partial longitudinal section illustrating the device in worln'ng position in relation to a cylinder severally specified in .the appendedwhich is closed at one end
- Fig. 5 is a transverse section through the shaft and tool-holder as constructed for the boringwheel 18 or any other satisfactory means,-
- auxiliary bearing blocks 20., 20 are provided for alining said shaft axially with the bore of the cylinder 22 to be operated upon, as in the prior patent referred to.
- the bearing bracket members 8 and 10 are clamped in the proper position, asdetermined by said temporary bearings, by means of a pair of yoke rods 24, the transverse portion of each of which is adapted tobe seated in one of the grooves '26 of the member 10, the member 8 having similar grooves 26 for seatingthe 'tie bars 28 which are held in place by the clamp nuts 30 on the threaded ends of the rods 24.
- the said screw 38 projects within the slotted end of the shaft 2- and has its outer end clamped by a screw 40 inthe head of a yoke member 42,
- the tool 4 I "fits within an axial bore 46 of the holder 6, cylinder and with the auxiliary bearing.
- Fig. 4 is shown an arrangement adapting the device for use in connection with cylinders having one end closed so that it is possible to insert only one of the auxiliary bearing members 20 for centering the shaft 2.
- the bearing bracket members 8 and 10 must therefore be adjusted and clamped on the same end of the cylinder. This. is done by assembling the parts as shown, with the plate portions of the bracket members clamped directly together by the bolts 60 and their bearings 14 and 16 projecting in opposite directions and the bearing 14 extending within the base of the cylinder.
- the bracket member 10 is provided with dowel pins 62 adapted to be received in openings64 in the member 8 for axially alining the bearings 14 and 16, and bolts 66 serve to secure the member 10 to the cylinder.
- the parts are clamped together after the shaft 2 has been properly alined by means of one of the temporary or auxiliary bearing blocks 20 and the latter removed.
- the yoke 42 is omitted and the feed screw 38 is passed through the spark plug opening of the cylinder where the plug 68 is suitably recessed as shown to receive the nut 36 and provided with the bayonet slot 32 for engagement with the pin of the said nut.
- the other end of the' feed screw is secured to the tool block or holder which in this case is shown provided with a threaded mounting the tool in this manner the holder is provided with a threaded shank 70 extending at right angles to the axis of the tool and adapted to be threaded into the socket 72 formed in one end of the shaft 2.
- the shaft is rotated as usual to cut along the interior surface of the cylinder. It is may be done by simply removing the holder without unclamping the screws 58 and 50 7 while the shaft is being transferred from one cylinder to another and then refitting the holder to the shaft with the tool in the same relative position as before. It will also be observed that by use of the yoke arrangement for connecting the bracket members, a quick clamping construction is obtained which requires only the tightening of the nuts after the shaft has been centered; and also that 'the new feeding arrangement shown affords an improved bearing action because of both of the bearings for the shaft being left smooth.
- Fig. 4 The operation of the construction and arrangement illustrated. in Fig. 4 is sufliciently indicated in the foregoing, the centering operation being similar to that stated excepting that but one temporary bearing block is used, and the arrangement of the bearings is modified as shown to meet the requirements of the closed-end type of cylinder, the use of the rods 24 being, of course, unnecessary in this relation.
- the yoke 42' is also dispensed with in the cutting operation, due to the mounting of the feed screw through the spark-plug opening, and the mounting of the tool is slightly modified in order to enable the cutting to take place at the extreme inner end of the-shaft.
- a device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means including a nut having a detachable connection with one end of said shaft, said connection acting to hold said nut fixed against movement relatively to the shaft.
- a device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means comprising a cooperating screw and nut alined axially with said shaft, said nut and one end of said shaft being provided with a pin and openslot connection permitting detachment of the shaft from said nut.
- a device for re-boring cylinders comprising, in' combination, a. cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means comprising a screw and a split nut cooperating therewith, said nut having a detachable connection with one end of said shaft, acting to hold the nut and shaft fixed against relative movement.
- a device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, means adapted to be positioned in the cylinder bore for alining said shaft axially therein, and additional means for feedingsaid shaft through the cylinder as the shaft is rotated, said feeding means having one element thereof provided with a detachable connection with said shaft, acting during the feeding operation to hold said element and shaft fixed against relative movement.
- a device for r -boring cylinders comprising, in combination, a cutter-carrying shaft, means for alining said shaft axially in the cylinder, a feed screw, and a nut operable along said screw and detachably connected with one end of said shaft.
- a device for re-boring cylinders com prising, in combination, a. tubular cuttercarrying shaft, means for alining said shaft axially in the cylinder, a feed screw project ing into one end of the shaft andfixed against axial movement, and a'nut-operable along said screw and havinga detachable connection with said shaft.
- a device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, means for alining said shaft axlallyin shaft through the cylinder as the shaft is rotated, sai feeding means including a split nut provi 'ed with a detachable connection toone end of said shaft, adapted to hold said nut and shaft fixed against relative movement.
- a device for re-boring cylinders COIIL- prising in combination, a cutter-carrying shaft, a bearing for said shaft, means for alining said shaft and bearing members axially of the cylinder, a feed screw carried by said bearing and fixed against axial movement, and a nut operable along said screw andha'ving a detachable connection with said shaft.
- a device for re-boring cylinders comprising, in combination, a tool-carrying shaft, means for alining said shaft axially in the cylinder, a feed screw, and a split nut operable along said screw and having adetachable connection with said shaft, said shaft having a tubular portion adapted to receive said nut and hold the latter in cooperative engagement with said screw.
- a device for re-boring cylinders com-- prising in combination, a cutter carrying shaft, a pair of bearing brackets providing smooth bearings for said shaft, means for alining said shaft and bearings axially of the cylinder, 'and a pair of yoke members connecting opposite ends of the brackets for clamping said brackets, when alined, against opposite ends of the cylinder.
- a device for re-boring cylinders comprising, .in combination, a cutter-carrying shaft, a pair-of bearing brackets providing smooth bearings for said shaft, meansfor alining said shaft and bearingsaxially. of the cylinder, a yoke'member having its op- .the cylinder, and means for feeding said posite leg portions secured to opposite sides of one of said brackets, a feed screw carried by said yoke member and adapted to be presentedaxially of said shaft and bearings,
- Adevice forre-boring cylinders comprising, in combination, a cutter-carrying shaft, having'a bayonet slot atone end, and
- said feedingv means comprising a feed screwand a split nut operable along said screw, oneof the sections of said nut being provided with a pin adapted for detachable connection with the 'slot of saidshaft.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Drilling And Boring (AREA)
Description
- E. F. HEISER.
' CYLINDER REBORING DEVICE.
APPLICATION FILED MAY 24, 1915.
Lw'KQWn Patented June 20,1916.
% A TTOR/VEY EDGAR F. nnisnn, or KINGSTON, MISSOURI.
GYLINDER-REBORING DEVICE.
Specification of Letters Patent.
' Applicati n filed May 24, 1915. seria1no. 3o,1o5.
' anduseful Improvements in Cylinder-Reboring Devices, of which the following is a full. and exact specification.
This invention relates to devices for use in metal-working, and particularly totools and operating means therefor for truing out cylinders, such as engine cylinders, for
which it is desired .to provide eflicient portable means inmotor car shops for re-boring such cylinders accurately and at the same time as speedily as possible. A device of this character is shown in Patent No. 1,097,318 which was issued 'to me on May 19, 1914, and the present invention relates. to improvements over the machine of that patent.
One object in view, therefore, is to provide means for properly centering the toolconstruction and combinations of parts as carrying means within the cylinder, together with an improved bearing constructionfor the tool-carrying shaft, and also afeed arrangementfor said shaft whereby thelatter may be quickly removed at'the end of each operation. I
It is a still further object to provide a bearing and feed construction whereby the parts "may be assembled in proper axial alinement for operation on cylinders which are closed at one end.
With these and other objects in view, as
will appear in the course of the, description,-
the invention comprises various details of accompanying drawing which illustrates one embodiment of the invention which has been devised for carrying the same into practice, afterwhich those featuresiof hey improvements which are deemed to be novel will be claims.
In this drawing-Figure 1 is a perspec .tive view' of the device; Fig. 2 is a longi- 'tudinal sectional View of the same, illustrating the device in working relation to a .blocks inoperative position; Fig. 3 is a sec I tion on the line "IIIIII of Fig. 2 (on a larger scale); Fig. 4 is a View in partial longitudinal section illustrating the device in worln'ng position in relation to a cylinder severally specified in .the appendedwhich is closed at one end; and Fig. 5 is a transverse section through the shaft and tool-holder as constructed for the boringwheel 18 or any other satisfactory means,-
such as a power attachment, if desired, for imparting rotary movement to said shaft. Tapered auxiliary bearing blocks 20., 20, are provided for alining said shaft axially with the bore of the cylinder 22 to be operated upon, as in the prior patent referred to. When the shaft 2 and its bearings have been adjusted by means of these temporary bearings 20 in the manner explained in said patent, the bearing bracket members 8 and 10 are clamped in the proper position, asdetermined by said temporary bearings, by means of a pair of yoke rods 24, the transverse portion of each of which is adapted tobe seated in one of the grooves '26 of the member 10, the member 8 having similar grooves 26 for seatingthe 'tie bars 28 which are held in place by the clamp nuts 30 on the threaded ends of the rods 24.
- The feeding movement of the shaft is ob- 34* projecting from one section of a split Patented am so, rate.
the legs of which are held by suitable clamp screws 44 to member 10.
As willbe observed from Fig. 5, the tool 4 I "fits within an axial bore 46 of the holder 6, cylinder and with the auxiliary bearing.
and may be adjusted thereinby means of a screw 48 fitted in the opposite end of said 'bore and abutting the inner end or shank of opposite sidesof the bracket in operative position.
to fit a transverse bore 54 through the shaft 2, which is provided with a threaded opening 56 for a screw 58 for clamping the latter By means of this holder arrangement, the tool can be adjusted within the holder and the latter removed and reapplied to the shaft without disturbing the adjustment of the tool as first made.
In Fig. 4 is shown an arrangement adapting the device for use in connection with cylinders having one end closed so that it is possible to insert only one of the auxiliary bearing members 20 for centering the shaft 2. The bearing bracket members 8 and 10 must therefore be adjusted and clamped on the same end of the cylinder. This. is done by assembling the parts as shown, with the plate portions of the bracket members clamped directly together by the bolts 60 and their bearings 14 and 16 projecting in opposite directions and the bearing 14 extending within the base of the cylinder. The bracket member 10 is provided with dowel pins 62 adapted to be received in openings64 in the member 8 for axially alining the bearings 14 and 16, and bolts 66 serve to secure the member 10 to the cylinder. In this relation the parts are clamped together after the shaft 2 has been properly alined by means of one of the temporary or auxiliary bearing blocks 20 and the latter removed. In this use of the device, however, the yoke 42 is omitted and the feed screw 38 is passed through the spark plug opening of the cylinder where the plug 68 is suitably recessed as shown to receive the nut 36 and provided with the bayonet slot 32 for engagement with the pin of the said nut. The other end of the' feed screw is secured to the tool block or holder which in this case is shown provided with a threaded mounting the tool in this manner the holder is provided with a threaded shank 70 extending at right angles to the axis of the tool and adapted to be threaded into the socket 72 formed in one end of the shaft 2. By this means it will be clear that rotation of the shaft will' carry it and the tool along the feed screw in the direction of the closed end of the .cylinder.
From the foregoing the nature of the improvements and mode of operation of the same will be clearly understood. In the case of a cylinder open at both ends the shaft is centered by means of a pair of the blocks 20 inserted in the opposite ends of the cylinder, and the bearing members being thus properly positioned, are clamped by means of the yokes 24. The shaft can then be withdrawn sufliciently to remove the blocks 20, and the tool-holder and tool are then applied to the shaft, which is then placed in operative position to bring the tool within the cylinder and the nut 36 in proper engagement with the slotted end of the shaft. After adjusting the tool properly,
the shaft is rotated as usual to cut along the interior surface of the cylinder. It is may be done by simply removing the holder without unclamping the screws 58 and 50 7 while the shaft is being transferred from one cylinder to another and then refitting the holder to the shaft with the tool in the same relative position as before. It will also be observed that by use of the yoke arrangement for connecting the bracket members, a quick clamping construction is obtained which requires only the tightening of the nuts after the shaft has been centered; and also that 'the new feeding arrangement shown affords an improved bearing action because of both of the bearings for the shaft being left smooth.
The operation of the construction and arrangement illustrated. in Fig. 4 is sufliciently indicated in the foregoing, the centering operation being similar to that stated excepting that but one temporary bearing block is used, and the arrangement of the bearings is modified as shown to meet the requirements of the closed-end type of cylinder, the use of the rods 24 being, of course, unnecessary in this relation. The yoke 42' is also dispensed with in the cutting operation, due to the mounting of the feed screw through the spark-plug opening, and the mounting of the tool is slightly modified in order to enable the cutting to take place at the extreme inner end of the-shaft.
While the above represents what is now believed to be the preferred mode of practising the invention, the right is reserved to such formal changes and modifications as may fairly fall within the scope of the appended claims.
1 Claims.
1. A device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means including a nut having a detachable connection with one end of said shaft, said connection acting to hold said nut fixed against movement relatively to the shaft.
2-. A device for re-boring cylinders com-v prising, incombination, a cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means comprising a fixedly supported screw and a nut cooperating therewith, said nut having a detachable connection directly to one 'end of said shaft, said connection holding said nut and shaft fixed against relative movement.
3. A device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means comprising a cooperating screw and nut alined axially with said shaft, said nut and one end of said shaft being provided with a pin and openslot connection permitting detachment of the shaft from said nut. 1
4. A device for re-boring cylinders comprising, in' combination, a. cutter-carrying shaft, and means for feeding said shaft axially through the cylinder as the shaft is rotated, said feeding means comprising a screw and a split nut cooperating therewith, said nut having a detachable connection with one end of said shaft, acting to hold the nut and shaft fixed against relative movement.
A device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, means adapted to be positioned in the cylinder bore for alining said shaft axially therein, and additional means for feedingsaid shaft through the cylinder as the shaft is rotated, said feeding means having one element thereof provided with a detachable connection with said shaft, acting during the feeding operation to hold said element and shaft fixed against relative movement.
6. A device for r -boring cylinders comprising, in combination, a cutter-carrying shaft, means for alining said shaft axially in the cylinder, a feed screw, and a nut operable along said screw and detachably connected with one end of said shaft.
7. A device for re-boring cylinders com prising, in combination, a. tubular cuttercarrying shaft, means for alining said shaft axially in the cylinder, a feed screw project ing into one end of the shaft andfixed against axial movement, and a'nut-operable along said screw and havinga detachable connection with said shaft.
8. A device for re-boring cylinders comprising, in combination, a cutter-carrying shaft, means for alining said shaft axlallyin shaft through the cylinder as the shaft is rotated, sai feeding means including a split nut provi 'ed with a detachable connection toone end of said shaft, adapted to hold said nut and shaft fixed against relative movement.
9. A device for re-boring cylinders COIIL- prising, in combination, a cutter-carrying shaft, a bearing for said shaft, means for alining said shaft and bearing members axially of the cylinder, a feed screw carried by said bearing and fixed against axial movement, and a nut operable along said screw andha'ving a detachable connection with said shaft.
10. A device for re-boring cylinders comprising, in combination, a tool-carrying shaft, means for alining said shaft axially in the cylinder, a feed screw, and a split nut operable along said screw and having adetachable connection with said shaft, said shaft having a tubular portion adapted to receive said nut and hold the latter in cooperative engagement with said screw.
11. A device for re-boring cylinders com-- prising, in combination, a cutter carrying shaft, a pair of bearing brackets providing smooth bearings for said shaft, means for alining said shaft and bearings axially of the cylinder, 'and a pair of yoke members connecting opposite ends of the brackets for clamping said brackets, when alined, against opposite ends of the cylinder.
12. A device for re-boring cylinders comprising, .in combination, a cutter-carrying shaft, a pair-of bearing brackets providing smooth bearings for said shaft, meansfor alining said shaft and bearingsaxially. of the cylinder, a yoke'member having its op- .the cylinder, and means for feeding said posite leg portions secured to opposite sides of one of said brackets, a feed screw carried by said yoke member and adapted to be presentedaxially of said shaft and bearings,
and a nut operable along said screw and.
having a detachableengagement with the end of said shaft.
13. Adevice forre-boring cylinders comprising, in combination, a cutter-carrying shaft, having'a bayonet slot atone end, and
means for feeding said shaft axially through I the cylinder as the shaft rotates, said feedingv means comprising a feed screwand a split nut operable along said screw, oneof the sections of said nut being provided with a pin adapted for detachable connection with the 'slot of saidshaft.
i a EDGAR HEISER.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US3010515A US1187992A (en) | 1915-05-24 | 1915-05-24 | Cylinder-reboring device. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US3010515A US1187992A (en) | 1915-05-24 | 1915-05-24 | Cylinder-reboring device. |
Publications (1)
Publication Number | Publication Date |
---|---|
US1187992A true US1187992A (en) | 1916-06-20 |
Family
ID=3255950
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US3010515A Expired - Lifetime US1187992A (en) | 1915-05-24 | 1915-05-24 | Cylinder-reboring device. |
Country Status (1)
Country | Link |
---|---|
US (1) | US1187992A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4871285A (en) * | 1988-07-28 | 1989-10-03 | Moore John W | Cylinder boring apparatus and method |
US20160305397A1 (en) * | 2015-04-16 | 2016-10-20 | General Electric Company | Gearbox repair apparatus |
-
1915
- 1915-05-24 US US3010515A patent/US1187992A/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4871285A (en) * | 1988-07-28 | 1989-10-03 | Moore John W | Cylinder boring apparatus and method |
US20160305397A1 (en) * | 2015-04-16 | 2016-10-20 | General Electric Company | Gearbox repair apparatus |
US10107255B2 (en) * | 2015-04-16 | 2018-10-23 | General Electric Company | Gearbox repair apparatus |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2864268A (en) | Engine reconditioning equipment | |
US1187992A (en) | Cylinder-reboring device. | |
US2145091A (en) | Turning and slotting device for commutators, etc. | |
US2567856A (en) | Attachment for the spindle housings of drill presses | |
JP4315550B2 (en) | Work fixing device | |
US2360175A (en) | Chuck | |
US1771058A (en) | Work-locating pin for jigs | |
US2416402A (en) | Boring machine | |
US3174402A (en) | Loose jaw collet | |
US1823642A (en) | Armature commutator resurfacing or cutting machine | |
US1417278A (en) | Universal alignment bearing reamer and babbitting bar | |
US2015940A (en) | Apparatus for reboring engine bearings | |
US2441716A (en) | Micrometer setting device for boring machines | |
US3344690A (en) | Boring bar assembly | |
US1421073A (en) | Tool-adjusting micrometer | |
US1097318A (en) | Cylinder-reboring device. | |
US2672789A (en) | Cutter driver for machine tools | |
US1565709A (en) | Reaming machine | |
US1762670A (en) | Reamer for pipe threaders | |
US1630515A (en) | Reaming or boring tool | |
US1692460A (en) | Detachable bearing head for cutter shafts and the like | |
US1513899A (en) | Extensible headstock center for lathes | |
US914653A (en) | Reamer. | |
US1520382A (en) | Boring head | |
US1113067A (en) | Reamer. |