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US2417490A - Rivet bucking bar - Google Patents

Rivet bucking bar Download PDF

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Publication number
US2417490A
US2417490A US504142A US50414243A US2417490A US 2417490 A US2417490 A US 2417490A US 504142 A US504142 A US 504142A US 50414243 A US50414243 A US 50414243A US 2417490 A US2417490 A US 2417490A
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Prior art keywords
rivet
bar
head
ferrule
inertia
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Expired - Lifetime
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US504142A
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Hewes James Ellicott
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J15/00Riveting
    • B21J15/10Riveting machines
    • B21J15/36Rivet sets, i.e. tools for forming heads; Mandrels for expanding parts of hollow rivets

Definitions

  • This invention refers to riveting and more particularly to rivet bucking bars used in connection therewith. It has amongst its objects to provide a device of this nature that will be relatively easy to manipulate; that will be particularly suitable for soft riveting; that will do its work effectively; that will have an arrangement that will permit variation in the inertia weighting of the bar; that will have means for adjusting the amount of resiliency of the device, that will present an attractive appearance, and which can be used to pean over the rivet stem while the rivet hammer holds the head on the opposite side of the plates to be secured together by the finished rivet.
  • the conventional dolly bar is generally utilized for holding the head of a rivet while the hammer is striking the other end and forming it into tion is somewhat different from that of the dolly bar. It is especially'valuable for airplane riveting where the quarters are cramped and the rivets are hard to get to. It is provided with inertia weights or blocks that may be added or removed readily to vary the inertia of the device 'to suit the riveting to be done and make it easier for the user to hold. Also various resilient washers are arranged for to suit the size and length of the rivet and to control the size of the head developed by the bar.
  • the device is held to the rivet to be headed by a rubberlike ferrule that spreads as the head is formed therein and its inner diameter moves out of the wayso as to allow the rivet to fasten closely tothe plates it is used to hold together.
  • Figure 1 is a side view. of a bucking bar embodying this invention, with portions broken away to show internal construction;
  • Figure 2 is a'front end view of Figure 1;
  • Figure 3 is a longitudinal sectional view taken along the line 3+3 of Figure 1, and the parts separated to show method of assembly;
  • Figure 5 is a side view similar to Figure 1, but
  • a handle I is employed for the user to manipulate the device conveniently. It is preferably of pistol grip form provided with a recessed hole at 2 to receive the end portion 3 of the formin bar 4.
  • the forming bar is provided with an adjustable collar 5 as indicated, to press up against the rubber washers 6, which take up the shocks given the bar while in use.
  • a cap '1 screws on to the grip and covers the washers and supports the end 3 of bar 4.
  • the shank 8 of the bar 4 is made long enough to take as many inertia weights 9 as the maximum use of the device requires. These inertia weights are longitudinally and loosely slid on the bar over the end 3, by removing the handle and adjustable collar 5.
  • a collar l0 serves to hold the inertia weights together and is itself held to the bar by means of a set screw l l
  • An integral col ar I2 on the bar prevents the inertia weights from advancing beyond it towards the impact head portion I3 of the forming bar. The latter is long enough to be conveniently applied to the rivets to be operated on.
  • This portion is encompassed by resilient washers [4 adjacent to the collar l2, and by a hollow cylindrical shield 15; the front portion l6 of which is reduced to form an ex ternal surface and operating head H on which the recess 24 of a soft rubber ferrule I8 is slidably mounted, as shown in the drawings.
  • This ferrule is additiona ly held in place on the forming bar and shield by a coiled spring l9, which spirallyand flexibly screws on and attaches to the ferrule and fixed collar l2 and also forms a protective armor for the head of the tool.
  • ; rivet set 22; and head 23 of a pneumatic hammer is shown in Figure 3 to illustrate the use of the tool.
  • the ferrule I8 is placed over the stem of the inserted rivet in.
  • the inertia of the weights 9 resists the action. This flattens the rivet out as the sides of same come into contact with the internal surface 25 of the ferrule I8 and spreads same outwardly in a resilient manner and so controls the work that it forms the rivet end into an even cylindrical shape.
  • the jar on the forming bar passes through the forming bar after the inertia is overcome and is taken up by the rubber washers 6, so that the operator's hand can absorb it gradually.
  • the vibrations occurring in the plates and passing to the ferrule are also partial y taken up by the resilient washers I4.
  • the washers may be added to or removed to control the height of rivet head and prevent jarring of the machine excessively.
  • the bucking bar is held by the handle with one hand of the user, while the other hand grasps the body at the inertia weights and directs it to the rivet.
  • the curved and checkered form of the handle enable the tool to be held in the hand with the axis and direction of operation of the tool above, which permits the bucking bar to be manipulated thereby using the other hand for holding the inertia weights, as a kind of universal joint.
  • the hold on the tool enables the latter to control the riveting reaction and forming to be controlled effectively by the hands of the operator.
  • the tool is therefore easy on the operator to use, and affords proper contact with the rivet to give it the desired form and contact with the plates.
  • the tool is particularly suitable for riveting light flat materials together, as its operation coordinates with their vibration. This makes it especially suitable for aeroplane work where aluminum or other light thin metallic material is used.
  • a bucking bar comprising in combination, a forming bar, inertia weights or blocks mounted on said bar for adjustably weighting the forming bar, a rubberlike ferrule structurally connected with the said bar adapted for mounting over a rivet shank in a plate and acting as guide for the forming bar end portion to align therewith, said ferrule being compressed and reduced in height so as to allow the said operating head of the forming bar to impact the rivet and form a head thereon close to the plate and spread the ferrule to permit it, when the rivet is hammered on from the other side of the plate, means on the forming bar for adjusting the position of weights longitudinally thereon adjacent the middle of the bar and its axis so as to be in the direct line of the hammering and the number of weights or blocks in accordance with the amount of inertia to be 4 pact the rivet and form a, head thereon close to the plate and spread the ferrule to permit it, when the rivet is hammered on from the other side
  • a bucking bar comprising, a forming bar having one end portion carrying a collar thereon and the other end portion formed as an impact head with the intermediate portion arranged as a weight shank, a handle arranged to receive one end portion of the forming bar therein and holding same resiliently thereto, a washer slidable on the shank with a set screw for locking same in any position thereon, inertia weights or inertia blocks slidably mounted on the said bar, or blocks for placement on the shank adjacent the middle portion thereof longitudinally thereon about the thereof and to be held by the said washer, a fixed washer on the shank acting as a stop against the inertia weights or blocks and acting in conjunction with the first mentioned washer to hold the weights in between on the shank, resilient washers en the shank disposed against the fixed washer, a shield on the bar mountably pressing against the washers, a ferrule of rubber
  • a bucking bar comprising, a forming bar having one end portion carrying a collar thereon and the other end portion formed as an impact head with the intermediate portion arranged as a weight shank, a handle arranged to receive the end portion of the forming bar therein and holding same resiliently thereto, a washer slidable on the shank with a set screw for locking same in any position thereon, inertia weights for lacement on the shank adjacent the middle portion thereof longitudinally thereon about the axis thereof and to be held by the said washer, a fixed washer on the shank acting as a stop against the inertia weights and acting in conjunction with the first mentioned washer to hold the weights in between on the shank, resilient washers on the shank disposed against the fixed washer, a shield on the shaft against the washers, a ferrule of rubberlike material on the shield projecting in front thereof for placement on the rivet, and adapted for movement back towards the
  • the rivet can impact the rivet during operation of the hammer, a coiled spring for holding the ferrule in placeagainst the shield and aligned therewith, and a resilient member between the forming bar and handle for absorbing shocks from the forming bar when it impacts the rivet operated on by the hammer and form a head on the rivet against a plate to be riveted and on the opposite side thereof to that which the rivet hammer is used with the said bar.
  • a bucking bar of the class described comprising in combination, a forming bar havin an integral collar thereon adjacent its middle portion With an impact head portion extending from one side and a handle receiving portion on the other side, adjustable inertia weight means mounted on the said forming bar against the said collar and on the handle receiving portion so as to form a relatively large cylindrical body thereon for manual holding, a handle adjacent the end of the handle receiving portion, said handle bein of curved form disposed at right angle to the axis of the forming bar, a shield mounted and slidable on the said impact head portion, a spring element mounted on the integral collar and extending and surrounding over the said shield and beyond same, a ferrule for positioning over a rivet stem, of resilient material mounted on the end portion of the shield and also held by the spring element said ferrule having a passage therethrough for the impact head to pass through and resiliently allow the impact head to contact a rivet stem therein to spread the same into a head when the normal head of the rivet is struck by a riveting hammer

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Percussive Tools And Related Accessories (AREA)

Description

March 18, 1947 J. E. HEWES RIVET BUCKING BAR 2 Sheets-Sme t 2 Filed ,Sept. 28, 1943 Patented Mar. 18;, 1947 UNITED STATES PATENT OFFICE RIVET BUCKING BAR James Ellicott Hewes, Dundalk, Md. Application September 28, 1943, Serial No. 504,142
' (Cl. IS-53.5)
Claims.
This invention refers to riveting and more particularly to rivet bucking bars used in connection therewith. It has amongst its objects to provide a device of this nature that will be relatively easy to manipulate; that will be particularly suitable for soft riveting; that will do its work effectively; that will have an arrangement that will permit variation in the inertia weighting of the bar; that will have means for adjusting the amount of resiliency of the device, that will present an attractive appearance, and which can be used to pean over the rivet stem while the rivet hammer holds the head on the opposite side of the plates to be secured together by the finished rivet.
Other objects will become apparent as'the invention is more fully set forth.
The conventional dolly bar is generally utilized for holding the head of a rivet while the hammer is striking the other end and forming it into tion is somewhat different from that of the dolly bar. It is especially'valuable for airplane riveting where the quarters are cramped and the rivets are hard to get to. It is provided with inertia weights or blocks that may be added or removed readily to vary the inertia of the device 'to suit the riveting to be done and make it easier for the user to hold. Also various resilient washers are arranged for to suit the size and length of the rivet and to control the size of the head developed by the bar. The device is held to the rivet to be headed by a rubberlike ferrule that spreads as the head is formed therein and its inner diameter moves out of the wayso as to allow the rivet to fasten closely tothe plates it is used to hold together.
In the following description is outlined a form of this invention as an example of its structure, reference being made to the attached drawings in which:
Figure 1 is a side view. of a bucking bar embodying this invention, with portions broken away to show internal construction;
Figure 2 is a'front end view of Figure 1;
Figure 3 is a longitudinal sectional view taken along the line 3+3 of Figure 1, and the parts separated to show method of assembly;
another head. The weight of the bar is estab- Figure 4 is a view taken along the line 44 of Figure 3; and
Figure 5 is a side view similar to Figure 1, but
2 with parts of the rubber ferrule, shield and resilient washers broken away to show the positioning of the shank and rivet therein.
Similar reference characters refer to similar parts throughout the drawings.
In the drawings, a handle I, is employed for the user to manipulate the device conveniently. It is preferably of pistol grip form provided with a recessed hole at 2 to receive the end portion 3 of the formin bar 4. The forming bar is provided with an adjustable collar 5 as indicated, to press up against the rubber washers 6, which take up the shocks given the bar while in use. A cap '1 screws on to the grip and covers the washers and supports the end 3 of bar 4. The shank 8 of the bar 4 is made long enough to take as many inertia weights 9 as the maximum use of the device requires. These inertia weights are longitudinally and loosely slid on the bar over the end 3, by removing the handle and adjustable collar 5. A collar l0 serves to hold the inertia weights together and is itself held to the bar by means of a set screw l l An integral col ar I2 on the bar prevents the inertia weights from advancing beyond it towards the impact head portion I3 of the forming bar. The latter is long enough to be conveniently applied to the rivets to be operated on. This portion is encompassed by resilient washers [4 adjacent to the collar l2, and by a hollow cylindrical shield 15; the front portion l6 of which is reduced to form an ex ternal surface and operating head H on which the recess 24 of a soft rubber ferrule I8 is slidably mounted, as shown in the drawings. This ferrule is additiona ly held in place on the forming bar and shield by a coiled spring l9, which spirallyand flexibly screws on and attaches to the ferrule and fixed collar l2 and also forms a protective armor for the head of the tool. The phantom outline of the plates 20; rivet head 2|; rivet set 22; and head 23 of a pneumatic hammer is shown in Figure 3 to illustrate the use of the tool.
In the operation of the device, the ferrule I8 is placed over the stem of the inserted rivet in.
up by the inertia of the weights 9 resists the action. This flattens the rivet out as the sides of same come into contact with the internal surface 25 of the ferrule I8 and spreads same outwardly in a resilient manner and so controls the work that it forms the rivet end into an even cylindrical shape. The jar on the forming bar passes through the forming bar after the inertia is overcome and is taken up by the rubber washers 6, so that the operator's hand can absorb it gradually. The vibrations occurring in the plates and passing to the ferrule are also partial y taken up by the resilient washers I4. The washers may be added to or removed to control the height of rivet head and prevent jarring of the machine excessively. The bucking bar is held by the handle with one hand of the user, while the other hand grasps the body at the inertia weights and directs it to the rivet. The curved and checkered form of the handle enable the tool to be held in the hand with the axis and direction of operation of the tool above, which permits the bucking bar to be manipulated thereby using the other hand for holding the inertia weights, as a kind of universal joint. The hold on the tool enables the latter to control the riveting reaction and forming to be controlled effectively by the hands of the operator. The tool is therefore easy on the operator to use, and affords proper contact with the rivet to give it the desired form and contact with the plates. The tool is particularly suitable for riveting light flat materials together, as its operation coordinates with their vibration. This makes it especially suitable for aeroplane work where aluminum or other light thin metallic material is used.
. While but one general form of the invention is shown in the drawings and described in the specifications, it is not desired to limit this application for patent to this particular form or in any other way otherwise than limited by the scope thereof, as it is appreciated that other forms of construction could be made that would use the same principles and come within the scope of the appended claims.
Having thus described the invention, what is claimed is:
l. A bucking bar comprising in combination, a forming bar, inertia weights or blocks mounted on said bar for adjustably weighting the forming bar, a rubberlike ferrule structurally connected with the said bar adapted for mounting over a rivet shank in a plate and acting as guide for the forming bar end portion to align therewith, said ferrule being compressed and reduced in height so as to allow the said operating head of the forming bar to impact the rivet and form a head thereon close to the plate and spread the ferrule to permit it, when the rivet is hammered on from the other side of the plate, means on the forming bar for adjusting the position of weights longitudinally thereon adjacent the middle of the bar and its axis so as to be in the direct line of the hammering and the number of weights or blocks in accordance with the amount of inertia to be 4 pact the rivet and form a, head thereon close to the plate and spread the ferrule to permit it, when the rivet is hammered on from the other side of the plate, means on the forming bar for adjusting the position of weights longitudinally thereon adjacent the middle of the bar and its axis so as to be in the direct line of the hammering and the number of weights or blocks in accordance with the amount of inertia to be applied thereon, a pistol grip handle for the forming bar and resilient members in the handle for taking up vibration in the forming bar.
3. In combination with a rivet hammer ho1d ing a rivet head in a plate, a bucking bar comprising, a forming bar having one end portion carrying a collar thereon and the other end portion formed as an impact head with the intermediate portion arranged as a weight shank, a handle arranged to receive one end portion of the forming bar therein and holding same resiliently thereto, a washer slidable on the shank with a set screw for locking same in any position thereon, inertia weights or inertia blocks slidably mounted on the said bar, or blocks for placement on the shank adjacent the middle portion thereof longitudinally thereon about the thereof and to be held by the said washer, a fixed washer on the shank acting as a stop against the inertia weights or blocks and acting in conjunction with the first mentioned washer to hold the weights in between on the shank, resilient washers en the shank disposed against the fixed washer, a shield on the bar mountably pressing against the washers, a ferrule of rubberlike material on the shield projecting in front thereof for placement on the rivet and adapted for movement back towards the forming bar so same can impact the rivet during operation of the hammer and form a head on the rivet against a plate to be riveted and on the opposite side I thereof to that which the rivet hammer is used with the said bar.
4. In combination with a rivet hammer holding a rivet head in a plate, a bucking bar comprising, a forming bar having one end portion carrying a collar thereon and the other end portion formed as an impact head with the intermediate portion arranged as a weight shank, a handle arranged to receive the end portion of the forming bar therein and holding same resiliently thereto, a washer slidable on the shank with a set screw for locking same in any position thereon, inertia weights for lacement on the shank adjacent the middle portion thereof longitudinally thereon about the axis thereof and to be held by the said washer, a fixed washer on the shank acting as a stop against the inertia weights and acting in conjunction with the first mentioned washer to hold the weights in between on the shank, resilient washers on the shank disposed against the fixed washer, a shield on the shaft against the washers, a ferrule of rubberlike material on the shield projecting in front thereof for placement on the rivet, and adapted for movement back towards the forming bar so same. can impact the rivet during operation of the hammer, a coiled spring for holding the ferrule in placeagainst the shield and aligned therewith, and a resilient member between the forming bar and handle for absorbing shocks from the forming bar when it impacts the rivet operated on by the hammer and form a head on the rivet against a plate to be riveted and on the opposite side thereof to that which the rivet hammer is used with the said bar.
5. A bucking bar of the class described comprising in combination, a forming bar havin an integral collar thereon adjacent its middle portion With an impact head portion extending from one side and a handle receiving portion on the other side, adjustable inertia weight means mounted on the said forming bar against the said collar and on the handle receiving portion so as to form a relatively large cylindrical body thereon for manual holding, a handle adjacent the end of the handle receiving portion, said handle bein of curved form disposed at right angle to the axis of the forming bar, a shield mounted and slidable on the said impact head portion, a spring element mounted on the integral collar and extending and surrounding over the said shield and beyond same, a ferrule for positioning over a rivet stem, of resilient material mounted on the end portion of the shield and also held by the spring element said ferrule having a passage therethrough for the impact head to pass through and resiliently allow the impact head to contact a rivet stem therein to spread the same into a head when the normal head of the rivet is struck by a riveting hammer.
JAMES ELLICOTT HEWES.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS
US504142A 1943-09-28 1943-09-28 Rivet bucking bar Expired - Lifetime US2417490A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2671216A (en) * 1951-05-05 1954-03-09 Malcolm H Fox Nail holding device for pneumatic hammer tools
US2890455A (en) * 1957-04-11 1959-06-16 Skil Corp Nail driver
US3585838A (en) * 1968-03-28 1971-06-22 Joseph M Newlon Bucking bar
US5572900A (en) * 1994-08-01 1996-11-12 The Deutsch Company Reduced recoil bucking bar
US10071415B1 (en) * 2017-06-20 2018-09-11 Gulfstream Aerospace Corporation Ergonomic bucking bar
US10427277B2 (en) * 2011-04-05 2019-10-01 Ingersoll-Rand Company Impact wrench having dynamically tuned drive components and method thereof
US12151348B2 (en) 2012-05-31 2024-11-26 Black & Decker Inc. Power tool having latched pusher assembly
US12502756B2 (en) * 2016-10-17 2025-12-23 Black & Decker Inc. High inertia driver system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1100230A (en) * 1913-02-17 1914-06-16 Ulysses G Detwiler Riveting-tool.
US1276235A (en) * 1918-01-12 1918-08-20 Joseph D Loranger Dolly-bar.
US2230043A (en) * 1940-04-22 1941-01-28 Ready Machine Tool & Die Co In Punch stripper
US2301888A (en) * 1939-09-26 1942-11-10 Cleveland Pneumatic Tool Co Rivet set
US2333418A (en) * 1942-10-13 1943-11-02 Chicago Pneumatic Tool Co Dimpling apparatus
US2353559A (en) * 1942-04-03 1944-07-11 Jr James L Hajek Bucking tool

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1100230A (en) * 1913-02-17 1914-06-16 Ulysses G Detwiler Riveting-tool.
US1276235A (en) * 1918-01-12 1918-08-20 Joseph D Loranger Dolly-bar.
US2301888A (en) * 1939-09-26 1942-11-10 Cleveland Pneumatic Tool Co Rivet set
US2230043A (en) * 1940-04-22 1941-01-28 Ready Machine Tool & Die Co In Punch stripper
US2353559A (en) * 1942-04-03 1944-07-11 Jr James L Hajek Bucking tool
US2333418A (en) * 1942-10-13 1943-11-02 Chicago Pneumatic Tool Co Dimpling apparatus

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2671216A (en) * 1951-05-05 1954-03-09 Malcolm H Fox Nail holding device for pneumatic hammer tools
US2890455A (en) * 1957-04-11 1959-06-16 Skil Corp Nail driver
US3585838A (en) * 1968-03-28 1971-06-22 Joseph M Newlon Bucking bar
US5572900A (en) * 1994-08-01 1996-11-12 The Deutsch Company Reduced recoil bucking bar
US10427277B2 (en) * 2011-04-05 2019-10-01 Ingersoll-Rand Company Impact wrench having dynamically tuned drive components and method thereof
US12151348B2 (en) 2012-05-31 2024-11-26 Black & Decker Inc. Power tool having latched pusher assembly
US12208497B2 (en) 2012-05-31 2025-01-28 Black & Decker Inc. Power tool having latched pusher assembly
US12502756B2 (en) * 2016-10-17 2025-12-23 Black & Decker Inc. High inertia driver system
US10071415B1 (en) * 2017-06-20 2018-09-11 Gulfstream Aerospace Corporation Ergonomic bucking bar

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