US3232011A - Expanding tool - Google Patents

Description

Feb. 1, 1966 w. J. PINEAU 3,232,011

EXPANDING TOOL Filed July 5, 1963 Q INVEN WILFRED J. PlNEAU 4 mm, MM? MW ATTORNEYS 3,232,011 EXPANDING TOOL Wilfred Jay Pinean, Dearborn, Mich. assignor to Calumet & Hecla, Inc., Allen Park, Mich, a corporation of Michigan 1 Filed July 5, 1963, Ser. No. 293,088 20 Claims. (Cl. 51-1373) The present invention relates to an expanding too-1, and more particularly to a pneumatically actuated expanding tool for grinding, polishing, and lapping tubing inside diameters or cylindrical bores.

It is an object of the present invention to provide an expandable tool employing abrasive cloth or paper which may be inserted into a tube or the like, and expanded to provide a controlled radial force or pressure on the inner surface of the tube while the tool is linearly advanced and retracted and/or rotated or oscillated back and forth about its longitudinal axis.

' More specifically, it is an object of the present invention to provide a tool as described in the preceding paragraph in which expansion. of the tool is accomplished pneumatically and in which means are provided for blowing air through the tool to cool the same and to exhaust particles of abrasive dust and the like from a tube in which the tool is employed;

. Still more specifically, it is an object of the present invention to provide a tool which includes -a radially expandable bladder, means for exposing an outer surface of the bladder at the periphery of the tool, means for supporting abrasive sheet material over the surface of the bladder, means for applying air under controlled pressure to the interior of the bl-adder to press the abrasive, material against theeinner surface of a tube or the like withacontrolled force. j

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawing,

United States Patent approximately 40 to 50 thousandth-s of an inch.

illustrating a preferred embodiment of the invention,

wherein:

FIGURE 1 is a broken longitudinal section through the tool. i

. FIGURE 2 is a section on the line 2-2, FIGURE 1.

FIGURE 3 is a side elevation with parts in section of the housing. 7

FIGURE 4 is a section on the line 44, FIGURE 3. The tool disclosed herein is intended to be used in grinding, polishing, lapping," or otherwise operating on the inner surface of a tube oran elongated cylinder and is designed particularly to permit accurate control of radial pressure irrespective of the length of the tube. As best seen in FIGURES 1 and 2, a portion of a tube in which the tool is illustrated in operating position is indicated at T and the tool indicated generally at 10 is carried at the end of a drive tube 12 which may of course be of any required length so that the tool may be employed to finish the interior surface of elongated tubes.

p The tool 10 comprises a housing 14, details of which are best seen in FIGURES 3 and 4. The housing 14 comprises an initially generally cylindrical central portion 16 one side ofwhich is cut away as indicated at 17 to leave a lateral opening extending substantially the full length of the central portion of the housing and having a, width substantially equal to the inside diameter of the housing. At opposite ends thehousing is provided with exteriorly threaded portions 18 and 19.

Received within the intermediate portion of the housing 14 is an expandable bladder 24 which may for example be a length of gum rubber tubing. The ends of the expandable bladder 24 are sealed and for this purpose there is provided an end cap 26 having a central plug 28 shaped to be received within an end of the tubular bladder 24. The end cap 26 includes an internally threaded flange 30 adapted to engage the threaded end 20 of the housing. At the other end of the housing there is provided a plug 32 shaped to be received within the other end of the tubular bladder 24 and having a passage 34 extending therethrough. The plug 32 includes a reduced neck portion 36 grooved to receive an O-ring 38.

a A drive cap 40 is provided having an internally threaded cylindrical flange 42 adapted to be threaded on the reduced threaded end portion 19 of the housing. The drive cap at its opposite end includes a threaded portion 44 adapted to be screwed to 'the internally threaded end portion of the drive tube 12. The exterior endof the drive tube 12 is unthreaded and provides a smooth interior cylindrical surface fitting closely with the exterior surface of the reduced end portion 46 of the drive cap 40. The reduced end portion 46 is grooved to receive the sealing O-ring 48.

Means are provided for employing the air used to expand the bladder 24 in cooling of the tool and in blowing abrasive particles and the like ahead of the tool. For this purpose the drive cap 40 is provided with a plurality of inclined air passages 50 which communicate with air chambers 52, the latter being connected by passages 54 with a longitudinal air passage 56 extending through the drive cap 40. The outer ends of the chambers 52 are threaded to receive jet adjustment screws 58. In practice, three air chambers 52 and passages *50are preferred, and in FIGURE 2 it may be considered that the lower chamber 52 is displaced from its actual position for clarity. In addition, the lowermost jet adjustment screw 58 as illustrated in FIGURE 2, is in closed position but in practice the plurality of jet adjustment screws will normally be set at the same adjustment. It will be apparent that the air under pressure passes through the inclinedv passages 50 and can move ahead of the tool 10 through passages 60 provided between the outer surface of the housing 14 and the inner surface of the abrasive sheet material 62.

The housing 14 is provided with an elongated slot 20 to receive an edge of an abrasive sheet as'will subsequently be described. In addition, at its outer surface 7 Theabrasive material may be of any suitable type but excellent results are obtained using a pressure sensitive abrasive cloth or screen including open meshes which assist in maintaining the cloth in clean, efiicient condition as a result of air cleaning.

From the foregoing description it will be apparent that air admitted through the drive tube 12 passes through passages 56 and 34 into the interior of the expandable bladder 24, thus forcing it radially outwardly through the cut way portion 17 of the housing 14, as best indicated in FIGURE 2. The abrasive sheet material has one edge received in the slot 20 and extends substantially completely around the intermediate portion of the housing 14. The pressure of the bladder 24 acts directly against the inner surface of the abrasive sheet material in 10 laterally so that pressure will also be applied to the Patented Feb. 1, 1966 inner surface of the sheet material 62 by the pad 21. Thus, operating pressure is applied to the sheet material over a very considerable area, approximately 180 degrees in angular extent as illustrated. Moreover, the above described action tends to balance the tool in the bore of the tube T.

In operation the tool may be rotated and reciprocated as required, these motions being imparted of course by appropriate mechanism connected to the drive tube 12. Overheating as a result of friction is prevented by the provision of cooling air passing through the passages 50 and this air also tends to maintain the abrasive sheet material in clean eflieient operating condition and also serves to blow abrasive particles, dust and the like out of the tube.

Since the force applied to the abrasive sheet material is controllable by the pressure existing within the bladder, this force is of course accurately controllable by available means such for example as an adjustable pressure regulating valve which is diagrammatically indicated at 64. Moreover, since air pressure is employed to control the operating pressure of the abrasive sheet material, and since this air pressure is admitted to the tool 10 through the drive tube 12, the tube 12 may be of any practical length without adversely alfeeting the accuracy of control of the operating pressures.

The drawing and the foregoing specification constitute a description of the improved pneumatically expanding tool in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

I claim:

1. A tool comprising a head, a closed chamber therein having a radially movable wall, means for supporting flexible sheet material in position overlying said wall, means for continuously supplying air under controlled pressure to said chamber, continuously open air passage means in said head providing a continuous flow of air through said head from said chamber to the exterior thereof, and means forming air passages from one end of said head to the other between said sheet material and the exterior surface of said head.

2. A tool as defined in claim 1 in which said passage means are inclined to provide a longitudinal component to the direction of discharge of air from said passage means.

3. A tool as defined in claim 1 in which said passage means are adjacent one end of said head and inclined radially outwardly and toward the opposite end of said head.

4. A tool for engaging the inner surface of a tube and adapted for connection to an elongated drive tube, said tool having an elongated generally cylindrical head having a central chamber therein open at one side thereof, a flexible closed bladded in said chamber having its interior in communication with the interior of said drive tube and adapted to have a lateral portion thereof move laterally outwardly through the side opening of said chamber, means for supporting a flexible abrasive sheet on said head overlying the lateral portion of said bladder, said bladder being effective to press the abrasive sheet material against the inner surface of the tube at a pressure determined by fluid pressure within the bladder and drive tube.

5. A tool as defined in claim 4 comprising means for adjustably controlling the fluid pressure within said drive tube.

6. A tool for engaging the inner surface of a tube and adapted for connection to an elongated drive tube, said tool having an elongated generally cylindrical head having a central chamber therein open at one side thereof, a flexible closed bladder in said chamber having its interior in communication with the interior of said drive tube and adapted to have a lateral portion thereof move laterally outwardly through the side opening of said chamber, a yieldable pad of extensive area on said head at the side opposite the open side thereof, means for sup: porting a flexible abrasive sheet on said head overlying the lateral portion of said bladder and said pad, said bladder being effective to press the abrasive sheet material against the inner surface of the tube at a pressure determined by fluid pressure within the bladder and drive tube- 7. A tool for engaging the inner surface of a tube and adapted for connection to an elongated drive tube, said tool having an elongated generally cylindrical head having a central chamber therein open at one side thereof, a flexible closed bladder in said chamber having its interior in communication with the interior of said drive tube and adapted to have a lateral portion thereof move laterally outwardly through the side opening of said chamber, means for supporting a flexible abrasive sheet on said head overlying the lateral portion of said bladder, said bladder being effective to press the abrasive sheet iaterial against the inner surface of the tube at a pressure determined by fluid pressure within the bladder and drive tube, and air passage means in said head opening at the side of said head.

8. A tool as defined in claim '7 in which said passage means are inclined to project air forwardly of said head in the tube in which the head is operating.

9. A tool comprising an elongated generally cylindrical head, having an interior chamber open at one side, a flexible bladder in said chamber having a portion displaceable radially outwardly through the open side of said chamber by interior pressure, a yieldable pad on said head at the side opposite its open side, means for supporting a flexible abrasive sheet over said pad and over the portion of said bladder in said open side, and air supply means for supplying said bladder with air under pressure.

it). A tool comprising an elongated generally cylindrical head, having an interior chamber open at one side, a flexible bladder in said chamber having a portion displaceable radially outwardly through the open side of said chamber by interior pressure, a yieldable pad on said head at the side opposite its open side, means for supporting a flexible abrasive sheet over said pad and over the portion of said bladder in said open side, and air supply means for supplying said bladder with air under pressure, said head having air passage means connected to said air supply means and opening at the side of said head.

11. A tool as defined in claim It) in which said air passage means are inclined forwardly.

12. A tool comprising an elongated generally cylindrical head, having an interior chamber open at one side, a flexible bladder in said chamber having a portion displace able radially outwardly through the open side of said chamber by interior pressure, a yieldable pad on said head at the side opposite its open side, means for supporting a flexible abrasive sheet over said pad and over the portion of said bladder in said open side, and air supply means for supplying said bladder with air under pressure, said air supply means comprising a drive tube connected to said head for mechanical actuation thereof in a tube.

13. A tool comprising an elongated tubular housing having threaded ends and having an elongated opening at one side thereof terminating short of the threaded ends, a flexible tubular bladder in said housing, a cap threaded to one end of said housing having a plug received within one end of said bladder, a tubular plug received within the other end of said bladder, said plugs and bladder defining an expansible chamber, a drive cap threaded to the other end of said housing, a drive tube connected to said drive cap, an air passage extending through said drive cap and communicating with said tubular plug to carry air under pressure from said drive tube to said chamber, said housing having means thereon for supporting an edge of a sheet of flexible abrasive material in position to overlie the opening in said housing.

14. A tool as defined in claim 13, said bladder being of resiliently yieldable material.

15. A tool as defined in claim 13, said drive cap having inclined air passage means extending from its air passage to its side surface.

16. A tool as defined in claim 13, a yieldab'le pad on the side of said housing opposite said opening, and a sheet of abrasive material extending over the portion of said bladder in said opening'and over said pad.

17. A tool as defined in claim 16, said pad being formed of sheet rubber permanently bonded to said housing.

18. A tool as defined in claim 16, the portion of said bladder in said opening extending beyond said opening and cooperating with said pad to position said housing in centered position in a tube spaced laterally inwardly from the inner surface of the portion of said abrasive sheet material in the zones intermediate said pad and opening to provide for air flow longitudinally over said housing and forwardly of said head. r 1

19. A tool comprising a generally cylindrical head having a chamber therein, a tubular drive shaft connected to one end of said head, means for continuously supplying air under controlled pressure to said chamber through said shaft, said chamberhaving at least one radially mov- I. SPENCER OVERHOLSER, LESTER and between said sheet material and said head from the said one end of said head to the other, and a. continuously open air pass-age at the said one end of said head and connected to said chamber at one end and inclined outwardly and toward the other end of said head.

20. A tool as defined in claim 19 in which said head has a compressible pad of limited circumferential extent on the exterior thereof at the side opposite said movable wall, said pad and said wall extending radially outwardly beyond intervening portions of said head to define longitudinal air channels closed at the outer sides thereof when the head is inserted into a tube to polish the interior thereof. 7

References Cited by the Examiner UNITED STATES PATENTS 2, 146,195 2/1939 Schultz 51-1841 2,490,472 12/1949 Raske 51-492 2,601,048 6/1952 Monger 51-192 FOREIGN PATENTS 457,503 1 1/ 1936 Great Britain.

ROBERT C. RIORDON, Primary Examiner.

M. SWINGLE, Examiners.

Claims (1)

1. A TOOL COMPRISING A HEAD, A CLOSED CHAMBER THEREIN HAVING A RADIALLY MOVABLE WALL, MEANS FOR SUPPORTING FLEXIBLE SHEET MATERIAL IN POSITION OVERLYING SAID WALL, MEANS FOR CONTINUOUSLY SUPPLYING AIR UNDER CONTROLLED PRESSURE TO SAID CHAMBER, CONTINUOUSLY OPEN AIR PASSAGE MEANS IN SAID HEAD PROVIDING A CONTINUOUS FLOW OF AIR

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