US1416296A - Scaffold machine - Google Patents
Scaffold machine Download PDFInfo
- Publication number
- US1416296A US1416296A US444650A US44465021A US1416296A US 1416296 A US1416296 A US 1416296A US 444650 A US444650 A US 444650A US 44465021 A US44465021 A US 44465021A US 1416296 A US1416296 A US 1416296A
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- upright
- lever
- shoe
- grip
- machine
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G1/00—Scaffolds primarily resting on the ground
- E04G1/18—Scaffolds primarily resting on the ground adjustable in height
- E04G1/20—Scaffolds comprising upright members and provision for supporting cross-members or platforms at different positions therealong
Definitions
- This invention relates to scaffolding apparatus, and particularly to apparatus whereby, given suitable uprights spaced apart and from the front of a building or the like, the workers on the scaffold can from time to time raise or lower the platform ⁇ on which they work, on said uprights as supports without leaving the platform.
- cording to my invention there will be two climbing and supporting means or machines on the respective supports, the twomachines being practically alike and together supporting the planking or equivalent platform, the invention consisting inthe novel construction and arrangement of the parts of such a machine whereby the operations of raising and lowering ⁇ can be easily and readily accomplished, the elements of safety and re liability are assured, and the machine is simple and inexpensive.
- FIG. l in the accompanying' drawings shows a scaffold apparatus in front elevation embodying my invention
- Figure 2 is a side elevation
- ' Figure 3 is a vertical sectional view of one of the machines in place on its upright, the parts being in the positions Athey occupy at a time when the machine is undergoing lift- Hle;
- Figure 4 is a view similar to Figure 3, but showing the parts in the positionthey occupy when the machine gripsthe upright and is stationary;
- Figure 5 is a plan view of the machine, partly in section, omitting the means thereof for supporting the platform; y
- Figures 6 and 7- are sectional views on the lines 6-6 and 7-7, respectively, of Figures 3 and 4c; y
- Figure 8 is a side elevation, -partly in section, and on a larger scale than Figure 2;
- Figure l9 shows in plan a brace for the uprights.
- a ⁇ in Figure2 designates the front of a building, and o spaced uprights-which will rest on the gro-und and will preferably consist of woodenl lengths 2224s) and will further be progressively extended upward to any desired height by lapjointing or other# wise joining the ⁇ ends of said lengths, the uprights being secured tothe building at successive elevationsv by braces, such as c, shown in Figures l, 2 and 9; it will be understood that whenv in climbing with the use of my apparatus a machine is to-,pass a brace c above it, upon the machine having nearly reached said brace .another such brace vwill be firstV arranged immediately below the machine to permit the removal of the first brace.
- shoe structures are generally designated by the characters A and B;
- the shoe structure A consists of two vertical plates d; sleeves e spacing them attop and bottom; a long bar f extending through the plates and the upper sleeve; a bolt g having a nut g and penetrating the plates and the lower sleeve; sleeves it on the free or projecting ends of the bars f; nuts f on the ends of the bar; and braces z' connecting the bolt g and bar f (being penetrated by them), rthe nuts gand f being adapted to be screwed up to clamp the several parts mentioned tight and form a rigid structure; otherwise stated, each shoe A has opposite projecting brackets (formed by f, z., i), and on these the ends of the planking y' to form the platform (or rather two platforms, one inward and the other outward of the uprights 7)) is supported.
- the other shoe B is a plate 7c which preferably has each end sharpened so as to gripy the wood of the upright.
- the linking means in the present case includes two parallel pairs oflinks Z pivoted on bolts m in the plates d of.shoe A and the plate 7c of shoe B, being properly spaced by sleevesm. on the one vhand and the plate 7e on the other. It will be seen that the parts A, B, Z form a parallel lever sys- ⁇ tem where, as in the present case, there are two, upper and lower, linking means, which l, ,Y
- lever p which is substantially U-shaped in side elevation ( Figure 8) and has a long operating arm and a short power-arm, the latter being' pivoted at g to a linking means, here formed by two links 1, which is in turnconnected with a suitable pivot, as m, on shoe B, so that the lever system is capable of collapsing movement only iny such way that A can move relatively downwardy and B relatively upward: compare Figure 3, showing points o, Q and m alined7 so that the collapse can take place i only as just stated, with Figure 4;, showing lever p swung downward and the lever system collapsed and thus gripping the upright.
- lever p For holding lever p in the position shown in Figure a 1 provide it and shoe A with holes adapted to receive a vpin s, as an ordinary nail 5 .it will be observed that the members p 1 ⁇ - aford means for exerting collapsing pressure on the lever system so as to cause the shoes to grip the upright, the grip thus additionally obtained being maintained upon inserting the pin )s in lever p and shoe A.
- Shoe B is equipped with a pivoted dog t having a long outer arm and a short inner arm, the latter being pointed and reaching downward and adapted to bear againstthe upright and catch therein.
- Each machine includes a lifting means connected with its lever system and adapted to assume a shifting purchase on the upright.
- u is a lever that is fulcrumed in a block e and is connected with the shoe A by links w, the block being adapted to bear against a. face of the upright.
- Pivoted to the block one above the other are two shackles and y, each being substantially U-shaped in plan and straddling the upright.
- shackle a? When the lever is now to be depressed to effect the lifting, shackle a? is raised to bind' against the upright and prevent the blocktilting on its lower corner.
- the gripping means Sometimes in descending with the machine the gripping means may catch on an obstruction on the upright (as a nail left therein), so that power would have to be applied to the lever to overcome the obstruction and positively force down the gripping means (which, as will appear, is then rendered ineffective to grip) at this time shackle y is allowed to fall and so by purchase obtained on the upright keep the block from tilting on its upper right-hand corner.
- rlhe gripper formed by shoes A. and B is one which grips the upright under load but nieves freeiy upward on the upright when lifted. That is, once shoe BV obtains aneffective hold the pressure of the load on shoe A results in the shoes coacting to exert clamping pressure on the upright.
- the initial grip of B on the upright when A is free of the lifting force is rendered certain by the deg t", which bites or' catches in the upright however far B may perchance be spaced from the upright.
- the loperator can utilize the lifting means to controllably lower the gripper step by step, lever p being held up during each downward movement and at the end thereof pressed downward to cause the clamping of the upright until a fresh purchase can be taken on the upright by the lifter for the next downward movement; or dog t and said lever can simply be allowed to fall to cause the new purchase.
- a pair of slings a can be suspended from the projecting brackets of the two machines to support va cross-piece 2, the cross-pieces serving ⁇ to support material 3 used inthe building ⁇ construction.
- a scaffoldinachine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright7 a gripping member adapted to grip the opposite face of the upright, and linking means extending from one member across the upright iso to the other member and pivotally connecting said members.
- a scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the. upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and means to move one of said members toward and from the other.
- a scaffold machine adapted to be shifted vertically on a suitable upright including a gripping member adapted to grip one face of the upright, a load-carrying member adapted to bear against an opposite face of the upright at a point opposite the gripping member, and means, connecting said members, to move one toward andl from the other.
- a scaffold machine adapted to be shifted vertically on a suitable upright including a gripping member adapted to grip one face of the upright, a load-carrying member adapted to bear against an opposite face of the upright at a point opposite the gripping member, and a lever and a link pivoted one to one member and the other to the other and also pivotally connected together.
- a scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivot-ally connecting said members, and means to move one of said members toward and from the other including a lever pivoted to one member and operatively connected to the other.
- a scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and means, connecting said members, to limit the downward movementof the gripping memberl relatively to the other member.
- a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and a lifting means operatively connected with the load-carrying member and having vertically shiftable means to grip thevupright.
- a climbing scaffold apparatus the combination of a gripping means including a gripping member adapted to grip one face of the upright to be climbed and a loadcarrying member coupled with the gripping member for up and down movement relatively thereto and away from and also against an opposite face of the upright, and a lifting means including a lever operatively connected with the load-carrying member and a fulcrum-support for the lever shiftable on and adapted to grip the upright.
- a scaffold machine adapted to be shifted vertically on al suitable upright and including' a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means eX- tending from one member across the upright to the other member and pivotally connecting said members, and a lifting means adapted to be operatively connected with the upright and having lifting connection With the load-carrying member.
- a climbing apparatus the combination of a gripping means adapted to grip and thereby secure itself to the upright to be climbed on downward movement of said means but slidable upwardly free of said upright, and lifting means including a block to bear against a face of the upright, a shackle pivoted to the block and embracing and adapted to' bear' against the other face of the upright, a lever fulcrumed in the block and a link connect-ing the lever and liftino means.
- llfnln a scaold machine, the combination, with a gripping system including members to grip opposite faces of the uprights to be climbed and arranged opposite each other and a linking member pivotally connecting them, of means, connecting tvvo of said members, to move the first tWo members toward and from each other.
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- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Mechanical Engineering (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Movable Scaffolding (AREA)
Description
P. HOITSIVIA.
SCAFFOLD MACHINE.
APPLICATION FILED. FEB. 14| 192|.
Patented May 16, 1922.
3 SHEETS-#SHEET 1.'
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Fl HOITSIVIA.
SCAFFOLD MACHINE.
APPLlcAnoN men Fes. 14;1921.
Patented May 16, 1922..
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P. HOITSIVIA.
SCAFFOLD MACHINE.' APPLICATIQN FILED re.14.1921.
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Patented May 16, 1922.
3 SHEETS-SHEET 3.
4unir isa ermee.
PETER HOITSMA., 0F PATEK-SON, NEW JERSEY. i
SCAFFOLD MAGHIN E.
Application filed. February 14, 1921. Serial No. 444,650.
To all whom t 'may concern.'
Be it known that l, PETER HoITsMA, a citizen of the United States, residing at Paterson, in the county of Passaic and State of New Jersey, have invented certain new and useful Improvements in Scaffold Machines, of which the following is a specification.
This invention relates to scaffolding apparatus, and particularly to apparatus whereby, given suitable uprights spaced apart and from the front of a building or the like, the workers on the scaffold can from time to time raise or lower the platform `on which they work, on said uprights as supports without leaving the platform. ley
cording to my invention, there will be two climbing and supporting means or machines on the respective supports, the twomachines being practically alike and together supporting the planking or equivalent platform, the invention consisting inthe novel construction and arrangement of the parts of such a machine whereby the operations of raising and lowering` can be easily and readily accomplished, the elements of safety and re liability are assured, and the machine is simple and inexpensive.
Figure l in the accompanying' drawings shows a scaffold apparatus in front elevation embodying my invention;
Figure 2 is a side elevation;
'Figure 3 is a vertical sectional view of one of the machines in place on its upright, the parts being in the positions Athey occupy at a time when the machine is undergoing lift- Hle;
Figure 4 is a view similar to Figure 3, but showing the parts in the positionthey occupy when the machine gripsthe upright and is stationary;
Figure 5 is a plan view of the machine, partly in section, omitting the means thereof for supporting the platform; y
Figures 6 and 7- are sectional views on the lines 6-6 and 7-7, respectively, of Figures 3 and 4c; y
Figure 8 is a side elevation, -partly in section, and on a larger scale than Figure 2; and
Figure l9 shows in plan a brace for the uprights. n l
a` in Figure2 designates the front of a building, and o spaced uprights-which will rest on the gro-und and will preferably consist of woodenl lengths 2224s) and will further be progressively extended upward to any desired height by lapjointing or other# wise joining the` ends of said lengths, the uprights being secured tothe building at successive elevationsv by braces, such as c, shown in Figures l, 2 and 9; it will be understood that whenv in climbing with the use of my apparatus a machine is to-,pass a brace c above it, upon the machine having nearly reached said brace .another such brace vwill be firstV arranged immediately below the machine to permit the removal of the first brace.
'Two shoe structures, ladapted to bear against opposite sides of each upright o and pivotally connected by linking means, are provided, one being adapted to assume the downward pressureof the planking or other platform and the other to gri-p the upright, their coaction to insure the grip'being due to the linking means. These shoe structures are generally designated by the characters A and B; The shoe structure A consists of two vertical plates d; sleeves e spacing them attop and bottom; a long bar f extending through the plates and the upper sleeve; a bolt g having a nut g and penetrating the plates and the lower sleeve; sleeves it on the free or projecting ends of the bars f; nuts f on the ends of the bar; and braces z' connecting the bolt g and bar f (being penetrated by them), rthe nuts gand f being adapted to be screwed up to clamp the several parts mentioned tight and form a rigid structure; otherwise stated, each shoe A has opposite projecting brackets (formed by f, z., i), and on these the ends of the planking y' to form the platform (or rather two platforms, one inward and the other outward of the uprights 7)) is supported. The other shoe B is a plate 7c which preferably has each end sharpened so as to gripy the wood of the upright. The linking means in the present case includes two parallel pairs oflinks Z pivoted on bolts m in the plates d of.shoe A and the plate 7c of shoe B, being properly spaced by sleevesm. on the one vhand and the plate 7e on the other. It will be seen that the parts A, B, Z form a parallel lever sys-` tem where, as in the present case, there are two, upper and lower, linking means, which l, ,Y
is the preferred construction; and in this the preferred construction I find it best to allow collapsing movement of the lever system only in that way which involves movement of shoe A'downwardly or shoe B upwardly, and not in' the opposite direction (the reason for which will appear later)7 and to that end l fulcrum on a bolt o in shoe A a lever p which is substantially U-shaped in side elevation (Figure 8) and has a long operating arm and a short power-arm, the latter being' pivoted at g to a linking means, here formed by two links 1, which is in turnconnected with a suitable pivot, as m, on shoe B, so that the lever system is capable of collapsing movement only iny such way that A can move relatively downwardy and B relatively upward: compare Figure 3, showing points o, Q and m alined7 so that the collapse can take place i only as just stated, with Figure 4;, showing lever p swung downward and the lever system collapsed and thus gripping the upright. For holding lever p in the position shown in Figure a 1 provide it and shoe A with holes adapted to receive a vpin s, as an ordinary nail 5 .it will be observed that the members p 1^- aford means for exerting collapsing pressure on the lever system so as to cause the shoes to grip the upright, the grip thus additionally obtained being maintained upon inserting the pin )s in lever p and shoe A.
Shoe B is equipped with a pivoted dog t having a long outer arm and a short inner arm, the latter being pointed and reaching downward and adapted to bear againstthe upright and catch therein. p
Once the shoe B obtains a grip on the upright, as by its points catching in the same, the grip is perfected by the weight of the shoe A and the load it carries, the effect being to collapse the lever system and increase the pressure of B f (and consequently the hold which its points obtain) on the upright, as well as the frictional pressure of A thereon. The pressure thus obtained, if desired, for the sake of additional safety, can be increased as explained by forcing and locking down lever p.
Each machine includes a lifting means connected with its lever system and adapted to assume a shifting purchase on the upright. To this end u is a lever that is fulcrumed in a block e and is connected with the shoe A by links w, the block being adapted to bear against a. face of the upright. Pivoted to the block one above the other are two shackles and y, each being substantially U-shaped in plan and straddling the upright. When the operator elevates the handle or free end of the lever w the result is to shift the block n upwardly along the upright, link w acting as a fulcrum.; the shackles are at this time kept from binding on the upright by the operators free hand. When the lever is now to be depressed to effect the lifting, shackle a? is raised to bind' against the upright and prevent the blocktilting on its lower corner. Sometimes in descending with the machine the gripping means may catch on an obstruction on the upright (as a nail left therein), so that power would have to be applied to the lever to overcome the obstruction and positively force down the gripping means (which, as will appear, is then rendered ineffective to grip) at this time shackle y is allowed to fall and so by purchase obtained on the upright keep the block from tilting on its upper right-hand corner.
rlhe gripper formed by shoes A. and B is one which grips the upright under load but nieves freeiy upward on the upright when lifted. That is, once shoe BV obtains aneffective hold the pressure of the load on shoe A results in the shoes coacting to exert clamping pressure on the upright. The initial grip of B on the upright when A is free of the lifting force is rendered certain by the deg t", which bites or' catches in the upright however far B may perchance be spaced from the upright.
`W hen the lifting means comprising lever uand its adjuncts is operated (p being unlocked) each lifting movement thereof obviously results in openingy or releasing movement of the gripper or gripping means; the pivot 0 being outward of a vertical line through g, shoe A is shifted upwardly relatively to shoe B, lever 7) swinging to the position of Figure 3 and shoe B being prevented from movement downward past its position there shown by 1r-1Q VVhen the new position of the gripper has been attained the gripper assumes a fresh grip.
Bog t is not indispensable, but it insures certainty and also promptness of the gripping action once the weight of shoe A and its load is free to act. Y
lf the dog be held in inactive position and lever y? held up (Figure the gripper is ineffective to clamp the upright. For descending, therefore, the loperator can utilize the lifting means to controllably lower the gripper step by step, lever p being held up during each downward movement and at the end thereof pressed downward to cause the clamping of the upright until a fresh purchase can be taken on the upright by the lifter for the next downward movement; or dog t and said lever can simply be allowed to fall to cause the new purchase.
A pair of slings a can be suspended from the projecting brackets of the two machines to support va cross-piece 2, the cross-pieces serving` to support material 3 used inthe building` construction.
Having thus fully described my invention, what l claim is i y l. A scaffoldinachine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright7 a gripping member adapted to grip the opposite face of the upright, and linking means extending from one member across the upright iso to the other member and pivotally connecting said members.
2. A scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the. upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and means to move one of said members toward and from the other.
3. A scaffold machine adapted to be shifted vertically on a suitable upright including a gripping member adapted to grip one face of the upright, a load-carrying member adapted to bear against an opposite face of the upright at a point opposite the gripping member, and means, connecting said members, to move one toward andl from the other.
l. A scaffold machine adapted to be shifted vertically on a suitable upright including a gripping member adapted to grip one face of the upright, a load-carrying member adapted to bear against an opposite face of the upright at a point opposite the gripping member, and a lever and a link pivoted one to one member and the other to the other and also pivotally connected together.
5. A scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivot-ally connecting said members, and means to move one of said members toward and from the other including a lever pivoted to one member and operatively connected to the other.
6. A scaffold machine adapted to be shifted vertically on a suitable upright and including a load-carrying member adapted to bear against one face of the upright,a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and means, connecting said members, to limit the downward movementof the gripping memberl relatively to the other member.
ing a. load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means extending from one member across the upright to the other member and pivotally connecting said members, and a lifting means operatively connected with the load-carrying member and having vertically shiftable means to grip thevupright.
8. ln a climbing scaffold apparatus, the combination of a gripping means including a gripping member adapted to grip one face of the upright to be climbed and a loadcarrying member coupled with the gripping member for up and down movement relatively thereto and away from and also against an opposite face of the upright, and a lifting means including a lever operatively connected with the load-carrying member and a fulcrum-support for the lever shiftable on and adapted to grip the upright.
.9. A scaffold machine adapted to be shifted vertically on al suitable upright and including' a load-carrying member adapted to bear against one face of the upright, a gripping member adapted to grip the opposite face of the upright, linking means eX- tending from one member across the upright to the other member and pivotally connecting said members, and a lifting means adapted to be operatively connected with the upright and having lifting connection With the load-carrying member.
l0. ln a climbing apparatus, the combination of a gripping means adapted to grip and thereby secure itself to the upright to be climbed on downward movement of said means but slidable upwardly free of said upright, and lifting means including a block to bear against a face of the upright, a shackle pivoted to the block and embracing and adapted to' bear' against the other face of the upright, a lever fulcrumed in the block and a link connect-ing the lever and liftino means.
llfnln a scaold machine, the combination, with a gripping system including members to grip opposite faces of the uprights to be climbed and arranged opposite each other and a linking member pivotally connecting them, of means, connecting tvvo of said members, to move the first tWo members toward and from each other.
In testimony whereof l affix my signature.
PETER HOITSMA.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US444650A US1416296A (en) | 1921-02-14 | 1921-02-14 | Scaffold machine |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US444650A US1416296A (en) | 1921-02-14 | 1921-02-14 | Scaffold machine |
Publications (1)
Publication Number | Publication Date |
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US1416296A true US1416296A (en) | 1922-05-16 |
Family
ID=23765779
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US444650A Expired - Lifetime US1416296A (en) | 1921-02-14 | 1921-02-14 | Scaffold machine |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2424115A (en) * | 1944-12-14 | 1947-07-15 | Powell Archibald Douglas | Elevating support for scaffold platforms |
US2469716A (en) * | 1946-06-21 | 1949-05-10 | Santi Thomas G Di | Scaffold |
US2994475A (en) * | 1955-04-08 | 1961-08-01 | Ibm | Card feeding, sensing, and translating mechanism |
US3420334A (en) * | 1967-09-01 | 1969-01-07 | Albert K Talbot | Cantilever clamp for scaffold ledger |
US3970277A (en) * | 1974-10-15 | 1976-07-20 | Riblet Henry J | Scaffold bracket |
US6273381B1 (en) * | 1999-08-31 | 2001-08-14 | Redev Management Corporation | Load actuated lock |
US7152835B1 (en) * | 2000-01-05 | 2006-12-26 | Riblet Henry J | Bracket assembly lock |
-
1921
- 1921-02-14 US US444650A patent/US1416296A/en not_active Expired - Lifetime
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2424115A (en) * | 1944-12-14 | 1947-07-15 | Powell Archibald Douglas | Elevating support for scaffold platforms |
US2469716A (en) * | 1946-06-21 | 1949-05-10 | Santi Thomas G Di | Scaffold |
US2994475A (en) * | 1955-04-08 | 1961-08-01 | Ibm | Card feeding, sensing, and translating mechanism |
US3420334A (en) * | 1967-09-01 | 1969-01-07 | Albert K Talbot | Cantilever clamp for scaffold ledger |
US3970277A (en) * | 1974-10-15 | 1976-07-20 | Riblet Henry J | Scaffold bracket |
US4103856A (en) * | 1974-10-15 | 1978-08-01 | Henry Riblet | Adjustable scaffold bracket |
US6273381B1 (en) * | 1999-08-31 | 2001-08-14 | Redev Management Corporation | Load actuated lock |
US7152835B1 (en) * | 2000-01-05 | 2006-12-26 | Riblet Henry J | Bracket assembly lock |
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