US3397749A - Tool support arrangement - Google Patents

Tool support arrangement Download PDF

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Publication number
US3397749A
US3397749A US624822A US62482267A US3397749A US 3397749 A US3397749 A US 3397749A US 624822 A US624822 A US 624822A US 62482267 A US62482267 A US 62482267A US 3397749 A US3397749 A US 3397749A
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Prior art keywords
tool
housing
rod
elongated
support
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US624822A
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Gerald M Haskins
Robert L Durham
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General Electric Co
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General Electric Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25HWORKSHOP EQUIPMENT, e.g. FOR MARKING-OUT WORK; STORAGE MEANS FOR WORKSHOPS
    • B25H1/00Work benches; Portable stands or supports for positioning portable tools or work to be operated on thereby
    • B25H1/0021Stands, supports or guiding devices for positioning portable tools or for securing them to the work
    • B25H1/0028Tool balancers

Definitions

  • Another object of the invention is to provide a tool support device of the above type which is adjustable to position the tool at the desired height and which has adjustable counterbalancing means for suitably suspending tools of varying weight.
  • the present invention in a preferred embodiment relates to a tool device and support arrangement therefor comprising a tool having a rotatable operating member and a gripping member for manually holding the tool during rotation of the operating member, means for driving the rotatable member relative to the gripping member, the torque thus applied to the operating member reacting in reverse direction on the gripping member, support means for suspending the tool comprising an elongated tubular member having a slot therein and an elongated rod member extending in telescoping relation into the tubular member and movable relative thereto between an extended and a retracted position and having a projection arranged in the slot in closely fitting slidable relation therewith for preventing rotation of the elongated members relative to each other, means yieldably urging the elongated tubular and rod members toward retracted position, the tool being connected at the lower end of the rod, and hanger means at the upper end of the tubular member for suspending the support means and the attached tool from a fixed support, whereby
  • FIGURE 1 is a view in elevation of the tool support device of the present invention
  • FIGURE 2 is an enlarged detail view, partly broken away, of the FIGURE 1 device
  • FIGURE 3 is a sectional view of a portion of the air tool device showing the driving mechanism in the interior thereof;
  • FIGURE 4 is a cross-sectional view taken along the line 44 of FIGURE 3.
  • FIGURE 5 is a perspective detail view, partly broken away, of the driving mechanism shown in FIGURES 3 and 4
  • an air driven tool 1 such as a screwdriver having a housing 2 from which a rotatable shaft 3 projects connected to a socket 4 for engaging and turning a screw 5.
  • socket 4 has a hexagonal form for engaging the hexagonal head of the screw, but as will be understood, the screw-driver may be of blade-type or Phillips-type for engaging screw heads of complementary form.
  • the driving force could be derived from means other than air pressure.
  • air under pressure is introduced into tool 1 by a conduit 6 connected to hollow joint 7, the latter being connected to tool housing 2 by means of an externally threaded pipe 8 (see FIGURE 2) on which housing 2 is threadably mounted and secured by lock nut 9.
  • the air supply is thus conducted into the interior of housing 2 (see FIGURE 3) wherein it is directed, through suitable conduit means 10, to air-driven motor 11.
  • the operation of the tool is controlled by spring-loaded valve 25 which closes and opens conduit 10 to passage of the air, the valve being operated by external handle 26.
  • Motor 11 rotatably drives motor shaft 12 connected at its lower end by suitable gear reduction means (not shown) to screw-driver shaft 3 for driving the latter in the direction indicated by the lowermost arrow in FIG- URE 1.
  • motor 11 comprises a sleeve 13 fixed to stationary housing 2 and having an cecentric bore 14 in which is mounted radially-slotted cylinder 15 for rotation about the longitudinal axis of housing 2.
  • Axial spindle 16 fixed to cylinder 15 passes through upper and lower bearings 17, 18 which are fixed relative to housing 2 and which retain spindle 16 on the axis of housing 2 in freely rotatable position by suitable anti friction means such as ball bearings (not shown).
  • Vanes 19 are slidably arranged in the radial slots of cylinder 15. In operation, the air supply enters the interior of motor 11 through an inlet 20 (see FIGURE 4) and strikes the exposed portion of the adjacent vane 19 so as to rotate cylinder 15 in the direction indicated by the arrow.
  • each vane 19 As will be seen, continued rotation of cylinder 15 results, due to centrifugal motion, in outward radial movement of each vane 19 into the space provided by eccentric bore 14 of sleeve 13, and the arrangement is such that as each vane passes inlet 20, its exposed portion receives the driving force of the air entering from the inlet.
  • Outlet opening 21 in sleeve 13 communicates with vent openings 22 in the wall of housing 2 for exhausting the air from the housing interior. As each vane 19 moves around with its edge in contact with sleeve 13, it is pushed back into its slot.
  • FIGURES l and 2 This arrangement comprises an elongated rod 30 connected at its lower end to conduit joint 7 by universal joint 31 which has mutually perpendicular pivot axes transverse to the longitudinal axis of rod 30, and an elongated hollow tube 32 in which rod 30 is slidable in telescoping relation and which has a slot 33 extending along its longitudinal axis.
  • Fixed to rod 30 near the upper end thereof is a laterally projecting pin 34 which is received in slot 33 for freely sliding along the same but which coacts therewith for preventing rotation of rod 30 relative to tube 32.
  • Rod 30 is thus movable into and out of tube 30, with the limit of its travel being determined by the abutment of pin 34 against tube 32 at opposite ends of slot 33.
  • Rod 30 is yieldably held in a retracted position within tube 32 by helical tension spring 35 connected at its lower end to rod 30 by means of collar 36 secured to rod 30 by set screw 37 or the like.
  • Collar 36 is selectively positionable at different locations along the length of rod 30, and by abutting the bottom end of tubular member 30 holds tool 1 at the desired height depending on the position of collar 36 on rod 30.
  • Spring 35 is connected at its upper end to tube 32 by chain 38 adjustably attached to hook 39 fixed to tube 32.
  • tube 32 is provided with a universal joint 40 similar to universal joint 31.
  • a suitable hanger means is connected to joint 40 for the purpose of suspending the entire apparatus from a fixed support such as a pipe 41.
  • a hook shaped hanger 42 is secured to joint 48 and is hung over fixed support 41 and held thereon by a suitable retaining pin 43. The arrangement is such that hanger 42 is securely held against rotation about the longitudinal axis of tube 32 relative to support 41.
  • a tool device and support arrangement therefor comprising, in combination, a tool comprising a rotatable operating member and a gripping member for manually holding the tool during rotation of said operating member, means for driving said rotatable member relative to said gripping member, the torque thus applied to said operating member reacting in reverse direction on said gripping member, support means for suspending said tool comprising an elongated tubular member having a slot therein and an elongated rod member extending in telescoping relation into said tubular member and movable relative thereto between an extended and a retracted position and having a projection arranged in said slot in closely fitting slidable relation therewith for preventing rotation of said elongated members relative to each other, means yieldably urging said elongated tubular and rod members toward retracted position, said tool being connected at the outer end of one of said elongated members, and means at the outer end of the other of said elongated members for suspending said support means and said tool from a fixed support, whereby said reverse torque is prevented
  • said yieldable means comprising an extensible tension spring.
  • adjustable connecting .eans connecting said extensible tension spring at one end to said one elongated member, said connecting means being adjustable to selected positions along the latter memher and engaging said other member in retracted position of said elongated members for holding said tool at predetermined height.
  • a device as defined in claim 3 elongated connecting means at the other end of said spring and co-acting catch means secured to said other elongated member for adjusting the tension of said spring.
  • said elongated connecting means comprising chain means readily attachable at different points along its length to said catch means for varying the etfective length thereof connecting said spring to said catch means.
  • a device as defined in claim 1 universal joint means turnable only about axes transverse the longitudinal axis of said support means, and connecting said support means at one end to said tool and at the oposite end to said suspending means.
  • said driving means comprising an air-driven motor for rotating said operating member
  • said gripping member comprising housing means enclosing said motor, and hollow conduit means connected between said tool and said one elongated member and communicating with the interior of said housing means for introducing air under pressure into said housing means for driving said motor.
  • said adjustable connecting means comprises a collar surrounding said elongated rod member.

Description

Aug. 20, 1968 G. M. HASKINS ET AL 3,397,749
TOOL SUPPORT ARRANGEMENT Filed March 21, 1967 5670/0 M 15 05/6772 /?0Aer? 1i. Far/2am b al Eff/75mg.
United States Patent 3,397,749 TOOL SUPPGRT ARRANGEMENT Gerald M. Haskins, Hendersonvilie, and Robert L. Durham, Flat Rock, N.C., assignors to General Electric Company, a corporation of New York Filed Mar. 21, 1967, Ser. No. 624,822 8 Claims. (Cl. 173163) ABSTRACT OF THE DISCLGSURE Support for suspending a rotatable air-driven tool such as a screw driver from a fixed support comprises telescoping support mmebers held against relative rotation and urged together by a spring adjustably connected to one member by a slidable collar and to the other member by an adjustable chain to enable positioning tools of various weights at the desired height while preventing turning of the tool housing when held during use.
It is an object of the invention to provide a tool support device which substantially absorbs the torque resulting from operation of the tool and therefore facilitates handling of the tool by the operator.
Another object of the invention is to provide a tool support device of the above type which is adjustable to position the tool at the desired height and which has adjustable counterbalancing means for suitably suspending tools of varying weight.
Other objects and advantages will become apparent from the following description and the appended claims.
With the above objects in view, the present invention in a preferred embodiment relates to a tool device and support arrangement therefor comprising a tool having a rotatable operating member and a gripping member for manually holding the tool during rotation of the operating member, means for driving the rotatable member relative to the gripping member, the torque thus applied to the operating member reacting in reverse direction on the gripping member, support means for suspending the tool comprising an elongated tubular member having a slot therein and an elongated rod member extending in telescoping relation into the tubular member and movable relative thereto between an extended and a retracted position and having a projection arranged in the slot in closely fitting slidable relation therewith for preventing rotation of the elongated members relative to each other, means yieldably urging the elongated tubular and rod members toward retracted position, the tool being connected at the lower end of the rod, and hanger means at the upper end of the tubular member for suspending the support means and the attached tool from a fixed support, whereby the reverse torque is prevented from turning the gripping member.
The invention will be better understood from the following description taken in conjunction with the accompanying drawing, in which:
FIGURE 1 is a view in elevation of the tool support device of the present invention;
FIGURE 2 is an enlarged detail view, partly broken away, of the FIGURE 1 device;
FIGURE 3 is a sectional view of a portion of the air tool device showing the driving mechanism in the interior thereof;
FIGURE 4 is a cross-sectional view taken along the line 44 of FIGURE 3; and
FIGURE 5 is a perspective detail view, partly broken away, of the driving mechanism shown in FIGURES 3 and 4 Referring now to the drawing, and particularly to FIG- URE 1, there is shown an air driven tool 1 such a screwdriver having a housing 2 from which a rotatable shaft 3 projects connected to a socket 4 for engaging and turning a screw 5. Typically, the interior of socket 4 has a hexagonal form for engaging the hexagonal head of the screw, but as will be understood, the screw-driver may be of blade-type or Phillips-type for engaging screw heads of complementary form. It will also be understood that other types of rotatable tools could be employed in connection with the invention, and that the driving force could be derived from means other than air pressure. In the illustrated embodiment, air under pressure is introduced into tool 1 by a conduit 6 connected to hollow joint 7, the latter being connected to tool housing 2 by means of an externally threaded pipe 8 (see FIGURE 2) on which housing 2 is threadably mounted and secured by lock nut 9. The air supply is thus conducted into the interior of housing 2 (see FIGURE 3) wherein it is directed, through suitable conduit means 10, to air-driven motor 11. The operation of the tool is controlled by spring-loaded valve 25 which closes and opens conduit 10 to passage of the air, the valve being operated by external handle 26. Motor 11 rotatably drives motor shaft 12 connected at its lower end by suitable gear reduction means (not shown) to screw-driver shaft 3 for driving the latter in the direction indicated by the lowermost arrow in FIG- URE 1. As seen in FIGURE 4, motor 11 comprises a sleeve 13 fixed to stationary housing 2 and having an cecentric bore 14 in which is mounted radially-slotted cylinder 15 for rotation about the longitudinal axis of housing 2. Axial spindle 16 fixed to cylinder 15 passes through upper and lower bearings 17, 18 which are fixed relative to housing 2 and which retain spindle 16 on the axis of housing 2 in freely rotatable position by suitable anti friction means such as ball bearings (not shown). Vanes 19 are slidably arranged in the radial slots of cylinder 15. In operation, the air supply enters the interior of motor 11 through an inlet 20 (see FIGURE 4) and strikes the exposed portion of the adjacent vane 19 so as to rotate cylinder 15 in the direction indicated by the arrow. As will be seen, continued rotation of cylinder 15 results, due to centrifugal motion, in outward radial movement of each vane 19 into the space provided by eccentric bore 14 of sleeve 13, and the arrangement is such that as each vane passes inlet 20, its exposed portion receives the driving force of the air entering from the inlet. Outlet opening 21 in sleeve 13 communicates with vent openings 22 in the wall of housing 2 for exhausting the air from the housing interior. As each vane 19 moves around with its edge in contact with sleeve 13, it is pushed back into its slot. As will be understood, the torque applied by pressure of the air supply against motor vanes 19 for turning the latter in the indicated direction will result in a reaction torque which is exerted against housing 2 tending to turn it in the opposite direction, as shown by the arrows encircling housing 2 in FIGURE 1. In the use of tool 1, the operator normally holds it by manually gripping tool housing 2. In known types of support arrangements for tools of this nature, such reacting torque has made it diflicult for the operator to firmly hold the tool, has led to undue fatigue in using the tool, and has even resulted in the tool twisting out of the operators hands during use.
In accordance with the invention, these difficulties are overcome by an improved supporting arrangement of which an embodiment is shown in FIGURES l and 2. This arrangement comprises an elongated rod 30 connected at its lower end to conduit joint 7 by universal joint 31 which has mutually perpendicular pivot axes transverse to the longitudinal axis of rod 30, and an elongated hollow tube 32 in which rod 30 is slidable in telescoping relation and which has a slot 33 extending along its longitudinal axis. Fixed to rod 30 near the upper end thereof is a laterally projecting pin 34 which is received in slot 33 for freely sliding along the same but which coacts therewith for preventing rotation of rod 30 relative to tube 32. Rod 30 is thus movable into and out of tube 30, with the limit of its travel being determined by the abutment of pin 34 against tube 32 at opposite ends of slot 33. Rod 30 is yieldably held in a retracted position within tube 32 by helical tension spring 35 connected at its lower end to rod 30 by means of collar 36 secured to rod 30 by set screw 37 or the like. Collar 36 is selectively positionable at different locations along the length of rod 30, and by abutting the bottom end of tubular member 30 holds tool 1 at the desired height depending on the position of collar 36 on rod 30. Spring 35 is connected at its upper end to tube 32 by chain 38 adjustably attached to hook 39 fixed to tube 32.
At its upper end, tube 32 is provided with a universal joint 40 similar to universal joint 31. A suitable hanger means is connected to joint 40 for the purpose of suspending the entire apparatus from a fixed support such as a pipe 41. In the illustrated embodiment, a hook shaped hanger 42 is secured to joint 48 and is hung over fixed support 41 and held thereon by a suitable retaining pin 43. The arrangement is such that hanger 42 is securely held against rotation about the longitudinal axis of tube 32 relative to support 41.
By virtue of the described arrangement, the reverse torque exerted by the operation of the tool on housing 2 which is gripped by the user is transmitted through rod 31' by pin 34 to tube 32, whence it is transmitted to fixed support 41 through hanger 42. As a result, tool housing 2 is prevented from turning in any appreciable degree and is readily held for long periods of operation without undue fatigue of the user. By suitable positioning the adjustable collar 36 as described above, tool 1 in its retracted position is adjusted to a height most convenient for the user. The tension of spring 35 is readily adjustable by means of chain 38 for the purpose of accommodating tools of different weights simply by increasing or decreasing the effective length of chain between hook 39 and the upper end of spring 35.
While the present invention has been described with reference to particular embodiments thereof, it will be understood that numerous modifications may be made by those skilled in the art without actually departing from the scope of the invention. Therefore, the appended claims are intended to cover all such equivalent variations as come within the true spirit and scope of t'lfi invention.
What we claim as new and desire to secure by Letters Patent of the United States is:
1. A tool device and support arrangement therefor comprising, in combination, a tool comprising a rotatable operating member and a gripping member for manually holding the tool during rotation of said operating member, means for driving said rotatable member relative to said gripping member, the torque thus applied to said operating member reacting in reverse direction on said gripping member, support means for suspending said tool comprising an elongated tubular member having a slot therein and an elongated rod member extending in telescoping relation into said tubular member and movable relative thereto between an extended and a retracted position and having a projection arranged in said slot in closely fitting slidable relation therewith for preventing rotation of said elongated members relative to each other, means yieldably urging said elongated tubular and rod members toward retracted position, said tool being connected at the outer end of one of said elongated members, and means at the outer end of the other of said elongated members for suspending said support means and said tool from a fixed support, whereby said reverse torque is prevented from turning said gripping member.
2. A device as defined in claim 1, said yieldable means comprising an extensible tension spring.
3. A device as defined in claim 2, adjustable connecting .eans connecting said extensible tension spring at one end to said one elongated member, said connecting means being adjustable to selected positions along the latter memher and engaging said other member in retracted position of said elongated members for holding said tool at predetermined height.
4. A device as defined in claim 3, elongated connecting means at the other end of said spring and co-acting catch means secured to said other elongated member for adjusting the tension of said spring.
5. A device as defined in claim 4, said elongated connecting means comprising chain means readily attachable at different points along its length to said catch means for varying the etfective length thereof connecting said spring to said catch means.
6. A device as defined in claim 1, universal joint means turnable only about axes transverse the longitudinal axis of said support means, and connecting said support means at one end to said tool and at the oposite end to said suspending means.
7. A device as defined in claim 1, said driving means comprising an air-driven motor for rotating said operating member, said gripping member comprising housing means enclosing said motor, and hollow conduit means connected between said tool and said one elongated member and communicating with the interior of said housing means for introducing air under pressure into said housing means for driving said motor.
8. A device as defined in claim 3, wherein said adjustable connecting means comprises a collar surrounding said elongated rod member.
References Cited UNITED STATES PATENTS 1,486,120 3/1924 Bayles 248325 X 2,746,720 5/1956 Cannon l73l63 X 3,134,340 5/1964 Olsen 248325 X NILE C. BYE/RS, JR., Primary Examiner.
US624822A 1967-03-21 1967-03-21 Tool support arrangement Expired - Lifetime US3397749A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4033532A (en) * 1974-11-22 1977-07-05 Atlas Copco Aktiebolag Power tool support
DE2830906A1 (en) * 1978-07-13 1980-01-31 Maschf Augsburg Nuernberg Ag SCREW DEVICE FOR SCREWING IN AND TIGHTENING SCREWS WITH HIGH TIGHTENING TORQUE
US4371222A (en) * 1980-09-08 1983-02-01 Gorkiewicz Mitchell F Retractable scissors tong mechanism
DE9402241U1 (en) * 1994-02-10 1995-06-14 Likratec Drucklufttechnik Gmbh Screwdriver guide with brake
US5791619A (en) * 1996-11-01 1998-08-11 Phd, Inc. Anti-torque reaction arm
DE29709122U1 (en) * 1997-05-23 1998-09-24 Upat Max Langensiepen Kg Device for screwing in fasteners
DE19902206A1 (en) * 1999-01-21 2000-08-03 Audi Ag Suspension device for tool consists of sprung pull , pull-wire, telescopic spacer element with rod and sleeve
US6105687A (en) * 1997-12-12 2000-08-22 Atlas Copco Tools Ab Portable power tool with a power supply line support device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1486120A (en) * 1923-04-28 1924-03-11 Ingersoll Rand Co Mounting for rock drills
US2746720A (en) * 1952-12-23 1956-05-22 Fred F Cannon Posthole digger
US3134340A (en) * 1962-09-17 1964-05-26 Eutech Corp Balancer assembly

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1486120A (en) * 1923-04-28 1924-03-11 Ingersoll Rand Co Mounting for rock drills
US2746720A (en) * 1952-12-23 1956-05-22 Fred F Cannon Posthole digger
US3134340A (en) * 1962-09-17 1964-05-26 Eutech Corp Balancer assembly

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4033532A (en) * 1974-11-22 1977-07-05 Atlas Copco Aktiebolag Power tool support
DE2830906A1 (en) * 1978-07-13 1980-01-31 Maschf Augsburg Nuernberg Ag SCREW DEVICE FOR SCREWING IN AND TIGHTENING SCREWS WITH HIGH TIGHTENING TORQUE
US4371222A (en) * 1980-09-08 1983-02-01 Gorkiewicz Mitchell F Retractable scissors tong mechanism
DE9402241U1 (en) * 1994-02-10 1995-06-14 Likratec Drucklufttechnik Gmbh Screwdriver guide with brake
US5791619A (en) * 1996-11-01 1998-08-11 Phd, Inc. Anti-torque reaction arm
DE29709122U1 (en) * 1997-05-23 1998-09-24 Upat Max Langensiepen Kg Device for screwing in fasteners
US6105687A (en) * 1997-12-12 2000-08-22 Atlas Copco Tools Ab Portable power tool with a power supply line support device
DE19902206A1 (en) * 1999-01-21 2000-08-03 Audi Ag Suspension device for tool consists of sprung pull , pull-wire, telescopic spacer element with rod and sleeve
DE19902206C2 (en) * 1999-01-21 2001-09-20 Audi Ag Hanging device for a tool

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