US1884584A - Portable tool - Google Patents
Portable tool Download PDFInfo
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- US1884584A US1884584A US472983A US47298330A US1884584A US 1884584 A US1884584 A US 1884584A US 472983 A US472983 A US 472983A US 47298330 A US47298330 A US 47298330A US 1884584 A US1884584 A US 1884584A
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- United States
- Prior art keywords
- spindle
- rotor
- passage
- chamber
- motor
- Prior art date
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B23/00—Portable grinding machines, e.g. hand-guided; Accessories therefor
- B24B23/02—Portable grinding machines, e.g. hand-guided; Accessories therefor with rotating grinding tools; Accessories therefor
- B24B23/026—Fluid driven
Definitions
- This invention relates to portable tools, and to pressure iuid operated motors of the character adapted to serve as the power unitvOther objects and advantages of the invention will subsequentlyappear.
- Fig. 1 is a central lon ltudinal section through'an illustrative em odiment of the invention.
- Fig. 2 is a fragmentary sectional view through the motor, the view being taken on planes corresponding to! the linev 2-2 of Fi 3.? Y
- Fig. 3 is a section on the line 3-3 of Fig. 2.
- Fig. 4 is a longitudinal fragmentary sectional view on the line 4-4 of Fig. -5 show-ing a modified form of construction.
- Fig. 5 isa transverse section through the modified arrangement.
- 1 indicates a pressure fluid operated portable tool of the grinder type in which the illustrative embodiment of my invention is incorporated.
- This portable tool 1 comprises a rear handle section 2,
- a suitable tool herein a grinding wheelv 5 is suitably 4mounted upon aspindle 6 which f is-/supported ina series of bearings 7, 8 and 9.
- the bearing 7 is arranged in t e forward end of the (handle 4, the bearing 8 to the rear of the handle 4, and the bearing 9 forwardly,
- the motor 3 comprises a cylinder block 11, a pair 'of inner heads 12 l and 13,'a forward outer head 14 formed integral withsthe handle. 4, and a rear outer" head and governor'h'ousing 1/5.l
- the parts of the motor so far described are rigidly held together by studs 17 andfnuts 18, the studs being threaded into the member and f passing through openings 19 in the front outer eadmember 14 so that the cylinder member 11 and the inner heads 12 and13are clamped 55 between the portions 14 and 15.
- a casin member 2O is seated upon shoulders'21'an 22 upon the members 14 and 15 and surrounds the cylinder 'member 11. This casingis secured, as by small screws 23, to the member 60 15.
- the handle 2 is secured to the outer rear head member 15 by screws 25. f
- the cy inder member 11 is cylindrically bored as at 27 and that the axis of the spin- 05 ⁇ die 6 is oifset from the axis of the cylindricalv bore 27.
- the space between the inner head members 12 and 13 is divided into two com ⁇ partments by an intermediate head member ,y 28 which vis held' in central position by the 70 set screws 29.
- the spindle 6 is'bored centrally at its rear' end, as indicated at 31, ⁇ and near the forward 'end of the bore 31 a radially extending passage 32 opens into an annular ⁇ groove 33 within the 90 partition member 28.
- a radial passage 34 extends to the periphery of the partition 28 and has laterally opening ports f35 which open into chambers 36 and 37 respectively located at opposite sides of the partition member 28.
- the ports 35 which are inlet ports, open into the chambers 36 and37, which constitute cylinders proper, a short distance, in the direction of rotation, ahead of the point in the wall of the bore'27 which is Vnearest to the 9 axis of the spindle 6.
- the spindle 16 carries suitably keyed there-l ⁇ to and one within each'of the chambers 36 and 37, cylindrial rotor elements 39 and 4D, these rotor elements being, coaxi'alwith ther-95 spindie and of apdiameter such that their Y, peripheriessubstantially'contact with the inner'wallofthebore 27 at the point in the latter nearest the axis of the spindle 6. .y
- Each of the rotor members 39 and 40 is provided 1 with a pair of radial slots 41.
- each rotor is arran ed in a common diametric' lane so that t ey open oppositely to each ct er through the periphery of the rctor.
- the slots in thetwo rotors are at right angles to each other.
- Within the slots 4l there are slidably mounted radially movable vanes 42, preferably of micarta bakelite, orY other suitable similar material, though it will be obvious that metallic vanes may be vused if desired.
- a series of exhaust ports 43 open radially outward and connect the cylinder bores with the space between the members 11 and 20. This space therefore serves as an exhaust chamber and through its connection through a series of fine holes 44 with the atmosphere, ermits a-nearly silent escape of the exhaust uid.
- a regulated supply ofmotivefluid is supplied to the motor under both manual and automaticcontrol.
- the handle 2 contains a throttle valve 46 provided with an operating lever 47. This throttle valve controls the flow' of motive fluid from an inlet supply connection 48 Vthrough a passage 49, past the throttle valve 46, through the space Within the valve seat 50',n and then through a passage 51 into a chamber, 52 formed within the member 15.
- the throttle valve is normally maintained closed by a spring 53.
- Lubricant ma be supplied to the incoming air from a c amber 54 within the handle 2 through a passage 55.
- a overnor mechanism which comprises a holow spindle 57 supported in the rear end of the drive spindle 6 and rotated by the latter y 4 through a pin andslot connection 58.
- hollow spindle 57 is closed at its rear end butV vlts internal passage 59 communicates through radially opening ports 60 with the interior of the chamber 52.
- the sliding sleeve 61 normally held in abutment with a shoulder 62 herein formed integral with the spindle 57 is movable to close and open the orts 60 land thereby control the entrance ol motive fluid into the bore 59 and its resultant passage to the motor.
- the shoulder 62 is rovided at dlametrically opposite points wlth pairs of Vears 64 between which pivot pins 65 su port pivoted weights 66 whose heavier-en 67 tend'to move out as th speed of the motor increases, thereby causing their shorter rear ends 68 tc move the sleeve 61 against the pressure of a spring 69 to close communication the port 60 between the chamber 52 and e bore 59.
- the spring tension may be adjusted by adjustably positioning a follower 70 which may be held in a Yplurality of positxonsby means of a cotter'. pin 71 Yinsertihle 1n a series of holes 72.
- a modified ⁇ form of construction is illustrated.
- This type of construction difl'ers from that shown in Figs. l to 3 only in the modified arrangement of passa s and ports for the admission of motive fl u1d to the cylinder chambers 36 and 37.
- this form instead of admitting the motive fuid laterally to the chambers 36 and 37 thro h inlet ports 35, provision is made for the a ission of the fluid inwardly at spaced points along. the peripher of the cylinder.
- the cy nder member 11 1s rovided with a longitudinally extending e ar ent -which 1s traversed by a lontudlnally extending passage 76 running om end to end of the cylinder block.
- This passage is connected through an opening 77 at its central portion with a radially extending assage 34 in the intermediate partition mem r 28 and a series of orts 78 open inwardly through the wall of t e cylinder member 11 at suitably spaced intervals to admit iiuid to the chambers 36 and 37.
- This form of the invention also is obviously inexpensive to manufacture and possesses substantially all of the operating advanta es of the embodiment first described. i
- partition within said cylinder member dividing theI interior of the Alatter into different rotor chambers, rotors insaidchambers, a spindle supporting said rotors, and fluid distribution means for said rotor chambers including a fluid supply passage extend ing through said spindle and said partition.
- a cylinder member In a rotary pressure fluid operated motor, a cylinder member, heads therefor, a partition within said cylinder member dividing they interior'of the latter into different rotor chambers, rotors in said chambers, a
- spindle supporting said rotors, fiuid distribut-ion means for said rotor chambers including a fluid supply passage extending through said-spindle and said partition, and ports opening-laterally through the walls of said partition adjacentv the periphery thereof.
- a cylinder member In 'a rotary pressure fiuid operated motor, a cylinder member, heads therefor, a partition within said cylinder member dividing'the interior of the latter into 'different rotor chambers, rotors in said chambers, a
- a cylinder member in a rotary pressure fluid operated motor, a cylinder member, members coopery ating therewith to form alrotor chamber, a Vrotor in said chamber, a shaft upon which motor, a cylinder member, and members cooperating with said cylinder member to form a rotor chamber, one of said members having ar radially extending passageformed therein and a lateral port openin into the bore of i the rotor chamber, a rotor-1n said chamber, a
- said rotor is mounted, said rotor shaft being hollow, passage means formed in the wall of said rotor chamber connecting the interior of said hollow shaft with 'said rotor chamber for admitting fluid to the latter, exhaust means for said rotor chamber, and means for admitting a governed supply of motive fluid to said hollow shaft including a governor' supported coaxially with the latter and controlling the admission of fluid thereto, said governor including a hollow spindle rotating with said shaft and having an internal chamber communicating with the bore of said shaft andports opening from the periphery of said spindle into said internal chamber and speed controlled means controlling said ports.
- fiuid supply connections including a passage in said shaft and a communicating, radially extending passage in one of said members whichy cooperate with the cylinder member to form a rotor chamber, and means for exhausting fiuid from said rotor chamber.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Hydraulic Motors (AREA)
Description
Oct. 25,1932. l R- E; CROSS 1,884,584
PORTABLE TOOL Filed Aug. 4, 1930 a 'digg- Q ig 45 6160 l k6 w x5 40 J xx i 760 M 7/ '13 fn ,Qdi y d f .e0 1; .e8 32.56 53% M1/,9.4.
65A@ imm.
Patented ct. 25, 1932 N UNITED STATES 'PATENT' OFFICE Bonner n. onoss, or cLABExoNT, Naw mrsnmn AssmNor. 'ro sULLIvAN MACHINERY COMPANY, A conroiwrroN or nassacnusmrs ricamata Toor.
Application led August 4, 1880. Serial lo. 472,983.
This invention relates to portable tools, and to pressure iuid operated motors of the character adapted to serve as the power unitvOther objects and advantages of the invention will subsequentlyappear.
In the accompanying drawing in which for purposes of illustration two forms of the A1nvention are shown,v p.
Fig. 1 is a central lon ltudinal section through'an illustrative em odiment of the invention.
Fig. 2 is a fragmentary sectional view through the motor, the view being taken on planes corresponding to! the linev 2-2 of Fi 3.? Y
Fig. 3 is a section on the line 3-3 of Fig. 2. Fig. 4 is a longitudinal fragmentary sectional view on the line 4-4 of Fig. -5 show-ing a modified form of construction.,
Fig. 5 isa transverse section through the modified arrangement.
Referring to the drawing, and particularly vto Figs. 1 to 3 thereof, 1 indicates a pressure fluid operated portable tool of the grinder type in which the illustrative embodiment of my invention is incorporated. This portable tool 1 comprises a rear handle section 2,
` 'a motor section 3, and a front handle portion l4. A suitable tool, herein a grinding wheelv 5, is suitably 4mounted upon aspindle 6 which f is-/supported ina series of bearings 7, 8 and 9. The bearing 7 is arranged in t e forward end of the (handle 4, the bearing 8 to the rear of the handle 4, and the bearing 9 forwardly,
of,` the handle2. VThe motor 3 comprises a cylinder block 11, a pair 'of inner heads 12 l and 13,'a forward outer head 14 formed integral withsthe handle. 4, and a rear outer" head and governor'h'ousing 1/5.l The parts of the motor so far described are rigidly held together by studs 17 andfnuts 18, the studs being threaded into the member and f passing through openings 19 in the front outer eadmember 14 so that the cylinder member 11 and the inner heads 12 and13are clamped 55 between the portions 14 and 15. A casin member 2O is seated upon shoulders'21'an 22 upon the members 14 and 15 and surrounds the cylinder 'member 11. This casingis secured, as by small screws 23, to the member 60 15. The handle 2 is secured to the outer rear head member 15 by screws 25. f
R'eferrin to Figs. 2 and 3 it will be noted thatthe cy inder member 11 is cylindrically bored as at 27 and that the axis of the spin- 05 `die 6 is oifset from the axis of the cylindricalv bore 27. The space between the inner head members 12 and 13 is divided into two com` partments by an intermediate head member ,y 28 which vis held' in central position by the 70 set screws 29. The space surrounding the exterior of the cylinder member 11 and the sleeve memberserves as an exhaust space, as hereinafter described, and it will be noted that the sleeve member 20 is arranged co- 75 axially with'the spindle 6.' The spindle 6 is'bored centrally at its rear' end, as indicated at 31,\and near the forward 'end of the bore 31 a radially extending passage 32 opens into an annular\ groove 33 within the 90 partition member 28. A radial passage 34 extends to the periphery of the partition 28 and has laterally opening ports f35 which open into chambers 36 and 37 respectively located at opposite sides of the partition member 28. The ports 35, which are inlet ports, open into the chambers 36 and37, which constitute cylinders proper, a short distance, in the direction of rotation, ahead of the point in the wall of the bore'27 which is Vnearest to the 9 axis of the spindle 6.A v
The spindle 16 carries suitably keyed there-l `to and one within each'of the chambers 36 and 37, cylindrial rotor elements 39 and 4D, these rotor elements being, coaxi'alwith ther-95 spindie and of apdiameter such that their Y, peripheriessubstantially'contact with the inner'wallofthebore 27 at the point in the latter nearest the axis of the spindle 6. .y Each of the rotor members 39 and 40 is provided 1 with a pair of radial slots 41. The slots in each rotor are arran ed in a common diametric' lane so that t ey open oppositely to each ct er through the periphery of the rctor. The slots in thetwo rotors are at right angles to each other. Within the slots 4l there are slidably mounted radially movable vanes 42, preferably of micarta bakelite, orY other suitable similar material, though it will be obvious that metallic vanes may be vused if desired. At the opposite side of the line of substantial contact between the rotors and the bore of the.Y cylinder member a series of exhaust ports 43 open radially outward and connect the cylinder bores with the space between the members 11 and 20. This space therefore serves as an exhaust chamber and through its connection through a series of fine holes 44 with the atmosphere, ermits a-nearly silent escape of the exhaust uid.
A regulated supply ofmotivefluid is supplied to the motor under both manual and automaticcontrol. The handle 2 contains a throttle valve 46 provided with an operating lever 47. This throttle valve controls the flow' of motive fluid from an inlet supply connection 48 Vthrough a passage 49, past the throttle valve 46, through the space Within the valve seat 50',n and then through a passage 51 into a chamber, 52 formed within the member 15. The throttle valve is normally maintained closed by a spring 53. Lubricant ma be supplied to the incoming air from a c amber 54 within the handle 2 through a passage 55. Y
Within the chamber 52 there is mounted a overnor mechanism which comprises a holow spindle 57 supported in the rear end of the drive spindle 6 and rotated by the latter y 4 through a pin andslot connection 58. The
hollow spindle 57 is closed at its rear end butV vlts internal passage 59 communicates through radially opening ports 60 with the interior of the chamber 52. The sliding sleeve 61 normally held in abutment with a shoulder 62 herein formed integral with the spindle 57 is movable to close and open the orts 60 land thereby control the entrance ol motive fluid into the bore 59 and its resultant passage to the motor. The shoulder 62 is rovided at dlametrically opposite points wlth pairs of Vears 64 between which pivot pins 65 su port pivoted weights 66 whose heavier-en 67 tend'to move out as th speed of the motor increases, thereby causing their shorter rear ends 68 tc move the sleeve 61 against the pressure of a spring 69 to close communication the port 60 between the chamber 52 and e bore 59. The spring tension may be adjusted by adjustably positioning a follower 70 which may be held in a Yplurality of positxonsby means of a cotter'. pin 71 Yinsertihle 1n a series of holes 72.
From the description thus far given, the mode of operation of this embodiment of the openV the throttle valve 46 and permit the air to flow Vfrom the supply connection 48 throu h passage 49 Vand passage 51 into the chamrer 52 from which it will next pass through ports 60, bore 59, bore 31, radial passage 32, groove 83, and radial passage 34 1 to the laterally opening inlet ports thus entering the cylinders proper 36, 37. Here the fluid will act upon the vanes 42, causing rotation of the rotors 39 and 40 and therefore of the spindle 6. When the'vanes-overrun the exhaust ports 43, exhaust takes place into the outer chamber in the sleeve 2O and the exhaust fluid finally escapes to the atmosphere throughrthe ports 44.
It will be evident that as the motor speeds up and approaches the desired maximum speed, the heavier ends 67 of the governor Weights 66 will swing outward with the result that the governor sleeve 61 will be moved gradually to close the ports 60, thereby preventing over-speeding of the motor.
From the foregoing description it will be clear that there is provided in the mechanism described, a pressure fluid operated motor having very s1mple fluid supply connections, one of adequate starting torque and very uniform running torque, that the airis economi icallv used, and that a minimum number of machine operations are necessary in the production `of the motor. It will also be clear that the governor is readily accessible by the removal of the rear handle 2 and the withdrawal of the governor spindle 57 from its connection with the spindle 6 of the motor. By reason of the arrangement of the fluid supply assages altogether in the spindles and in t. e partition plate 28, the construction of the cylinder of the motor is made exceedingly simple and inexpensive.
In Figs. v4 and 5 a modified `form of construction is illustrated. This type of construction difl'ers from that shown in Figs. l to 3 only in the modified arrangement of passa s and ports for the admission of motive fl u1d to the cylinder chambers 36 and 37. In this form, instead of admitting the motive fuid laterally to the chambers 36 and 37 thro h inlet ports 35, provision is made for the a ission of the fluid inwardly at spaced points along. the peripher of the cylinder. t will be noted that the cy nder member 11 1s rovided with a longitudinally extending e ar ent -which 1s traversed by a lontudlnally extending passage 76 running om end to end of the cylinder block. This passage is connected through an opening 77 at its central portion with a radially extending assage 34 in the intermediate partition mem r 28 and a series of orts 78 open inwardly through the wall of t e cylinder member 11 at suitably spaced intervals to admit iiuid to the chambers 36 and 37.
The mode of operation of this arrangement is substantially identical with that of the other species. It may be noted lthat in this `vcase the fluid flows through the bore 31, an-
. This form of the invention also is obviously inexpensive to manufacture and possesses substantially all of the operating advanta es of the embodiment first described. i
Vhile there are in this application specifically described two forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invcntion may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.
What I claim as new` and desire to secure by Letters Patent is:
, l. ,In a rotary pressure fiuid operated A motor, a cylinder member, heads therefor, a
partition within said cylinder member dividing theI interior of the Alatter into different rotor chambers, rotors insaidchambers, a spindle supporting said rotors, and fluid distribution means for said rotor chambers including a fluid supply passage extend ing through said spindle and said partition.
In a rotary pressure fluid operated motor, a cylinder member, heads therefor, a partition within said cylinder member dividing they interior'of the latter into different rotor chambers, rotors in said chambers, a
spindle supporting said rotors, fiuid distribut-ion means for said rotor chambers including a fluid supply passage extending through said-spindle and said partition, and ports opening-laterally through the walls of said partition adjacentv the periphery thereof.
In 'a rotary pressure fiuid operated motor, a cylinder member, heads therefor, a partition within said cylinder member dividing'the interior of the latter into 'different rotor chambers, rotors in said chambers, a
` spindle supporting said rotors, and fluid distribution means for said'rotor chambers including a fluid supply passage extending throughsaid spindle and said partition, and
` a longitudinally extending viassa'ge formed in said cylinder member and having orts opens ing inwardly into said rotorcham ers.
4. In a rotary pressure fluid operated said hollow shaft with said rotor chamber for admitting fluid to the latter, exhaust means for said rotor chamber, and means for admitting a governed supply of motive fiuid to said hollow shaft including a governor supported coaxially with the latter and controlling the admission of fluid thereto. y
6. In a rotary pressure fluid operated motor, a cylinder member, members coopery ating therewith to form alrotor chamber, a Vrotor in said chamber, a shaft upon which motor, a cylinder member, and members cooperating with said cylinder member to form a rotor chamber, one of said members having ar radially extending passageformed therein and a lateral port openin into the bore of i the rotor chamber, a rotor-1n said chamber, a
said rotor is mounted, said rotor shaft being hollow, passage means formed in the wall of said rotor chamber connecting the interior of said hollow shaft with 'said rotor chamber for admitting fluid to the latter, exhaust means for said rotor chamber, and means for admitting a governed supply of motive fluid to said hollow shaft including a governor' supported coaxially with the latter and controlling the admission of fluid thereto, said governor including a hollow spindle rotating with said shaft and having an internal chamber communicating with the bore of said shaft andports opening from the periphery of said spindle into said internal chamber and speed controlled means controlling said ports.
7. In a rotary pressure fluid operated motor, a cylinder member, and members cooperating with said cylinder member to form arotonchambe'r, 'a rotor in said chamber, a
supporting shaft therefor, fiuid supply connections including a passage in said shaft and a communicating, radially extending passage in one of said members whichy cooperate with the cylinder member to form a rotor chamber, and means for exhausting fiuid from said rotor chamber.
In testimony whereof I aflix my signature.
ROBERT E. CROSS.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US472983A US1884584A (en) | 1930-08-04 | 1930-08-04 | Portable tool |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US472983A US1884584A (en) | 1930-08-04 | 1930-08-04 | Portable tool |
Publications (1)
Publication Number | Publication Date |
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US1884584A true US1884584A (en) | 1932-10-25 |
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Application Number | Title | Priority Date | Filing Date |
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US472983A Expired - Lifetime US1884584A (en) | 1930-08-04 | 1930-08-04 | Portable tool |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2952249A (en) * | 1958-02-27 | 1960-09-13 | Master Power Corp | Pneumatic motor |
US3048150A (en) * | 1960-09-23 | 1962-08-07 | Herschal Products Inc | Pneumatically operated tool |
US3071115A (en) * | 1961-07-06 | 1963-01-01 | Thomas C Wilson Inc | Pneumatic motor with overspeed safety device |
-
1930
- 1930-08-04 US US472983A patent/US1884584A/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2952249A (en) * | 1958-02-27 | 1960-09-13 | Master Power Corp | Pneumatic motor |
US3048150A (en) * | 1960-09-23 | 1962-08-07 | Herschal Products Inc | Pneumatically operated tool |
US3071115A (en) * | 1961-07-06 | 1963-01-01 | Thomas C Wilson Inc | Pneumatic motor with overspeed safety device |
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