US1203206A - Sheet-metal brake. - Google Patents

Sheet-metal brake. Download PDF

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US1203206A
US1203206A US4892715A US4892715A US1203206A US 1203206 A US1203206 A US 1203206A US 4892715 A US4892715 A US 4892715A US 4892715 A US4892715 A US 4892715A US 1203206 A US1203206 A US 1203206A
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clutch
sheet
handle
shaft
metal
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US4892715A
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Nic Krump
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C31/00Control devices, e.g. for regulating the pressing speed or temperature of metal; Measuring devices, e.g. for temperature of metal, combined with or specially adapted for use in connection with extrusion presses
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D3/00Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
    • B21D3/12Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by stretching with or without twisting

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  • Arrak/vzx Mm PETERS ca, PNOm-LHNCL. WASNINCIDH. n. L
  • This invention relates to devices for bending sheet metal and used by sheet metal workers, and known in the sheet metal art as brakes.
  • the object of this invention is to obtain a sheet metal brake which is adapted to bend sheets of metal of various thickness; to obtain a device in which sheets of metal will be held firmly and bent on a determined line; and to obtain a power driven device of the kind named wherein a sheet holding mechanism, while adapted to be applied to hold a sheet of metal rigidly in place, will not be broken bythe lack of skill or inatten tion of the person or persons operating the same.
  • a'further object is to obtain a holding mechanism in a brake of the character described which may be set, so that when a large number of sheets of metal of the same thickness are to be bent the said holding mechanism will be automatically disconnected from the motive power which is applied thereto to obtain a desired grasp or hold on the sheet of metal which is to be bent.
  • Figure 1 is a perspective of a brake provided with holding mechanism embodying this invention.
  • Fig. 2 is an end view of said brake, showing a mechanism embodying this invention thereon, witha portion of a worm driven wheel which forms an element of said mechanism removed, to xpose to view a cam and a cam shaft, which are also elements of the mechanism.
  • Fig. 3 is a vertical sectional View of a link, cam and worm wheel and a side elevation of the shafts thereof, said section being taken on line 3-3 of Fig. 2 and viewed in the direction indicated by the arrows.
  • Fig. 4 is a front View of said link.
  • Fig. 5 is an end elevation of a clutch sleeve forming an element of mechanism embodying the invention.
  • Fig. 6 is a side elevation of said clutch sleeve.
  • A, A represent standards forming the ends of the brake.
  • B is a table on which sheets of metal to be bent may be laid.
  • C is an apron which is turned on shaft D; and E (Fig. 1), is an angle-iron which is rigidly secured to the upper edge of the apron C, and by means of which a sheet of metal which is placed on table l3 and held rigidly thereto, by the mechanisms embodying this invention, is bent.
  • F is a movable body which is mounted to rock on shaft f in slot f forming the upper jaw of the clamp of the brake, andsaid upper jaw is provided at the forward and holding edge thereof with the holding or grasping plate G.
  • the sheet of metal to be bent is placed on table B and is brought out in front of the holding plate G and rigidly held by said plate G as apron C and angle iron E are turned on shafts D, and said angle iron E bends said sheet.
  • the mechanism by means of which the upper jaw F and holding or grasping plate G are moved, to raise said plate G from, and bring it to, a sheet or strip of metal which is to be held thereby and bent by apron C and angle iron E, embodies this invention.
  • Said mechanisms are positioned on standard A, at both ends thereof, and are duplicates (but may be rights and lefts) and each of said mechanisms comprises the following described parts.
  • H represents a shaft which is secured to standard A; it represents a spur shaft which is secured to the upper jaw F.
  • I I represents a link, J a cam and K a worm wheel.
  • L, L L represent shafts journaled in bearings M, and M M and M and M respectively.
  • L represents a driving shaft which is journaled in suitable bearing on standards A A, and N a beveled gear, which is rigidly secured to driving shaft L n represents a beveled gear intermeshing, with gear N.
  • Beveled gear a and gear a are connected or joined to turn in unison, and are mounted loosely on shaft L.
  • N and a represent gears which are rigidly secured on shaft L to turn therewith.
  • N is a gear wheel on shaft L and N is a gear wheel which is loosely mounted on shaft L.
  • Gears 719, N intermesh; and also gears W, N and N a is a worm wheel which is secured on keyed on shaft L to turn therewith while longitudinally movable thereon; said longitudinal movement being controlled by the handle Q which is pivoted to standard A at Q.
  • the clutch wheel P is provided with the groove 19, in which said handle Q fits and with the clutch teeth p and 10 R is a clutch wheel rigidly secured to the gear wheel a to turn therewith and r is a clutch wheel which is rigidly secured to the gear wheel N to turn therewith.
  • the handle Q is moved down to force the clutch P into gear with clutch R, and bring the holding bar G of the upper jaw F down into holding or grasping position on a sheet of metal on tableB; and said handle is moved up to force said clutch P into gear with clutch 7 to raise said holding bar G from said grasping position.
  • the clutches R and r turning in opposite directions, as hereinbefore described, enable me to move the grasping bar G down and up the required distance to operate it, by rocking said worm gear wheel K and cam J on their shaft. That is, they are not rotated or caused to turn a complete revolution.
  • the clutch teeth 79 on clutch P are forced into engagement with the teeth of clutch wheel R and when said handle is moved up from said illustrated position the clutch teeth p are moved into engagement with the teeth of clutch wheel 7*.
  • Sheets or strips of metal of different thicknesses are bent or folded on the brake illustrated, and to prevent breaking of the mechanism embodying this invention, (when said holder is pressing with determined force on the sheet or strip of metal thereunder), the engaging faces of the clutch teeth 32 and the teeth on clutch R are made of such shape that the same can not be held in engagement, by a person grasping the handle Q, after a predetermined pressure of bar G is obtained said handle being forced upward by said engaging faces.
  • the handle Q being forced up as aforesaid, the person holding it down and feeling the upward movement thereof, will not resist the same; on the contrary being thereby notified or warned, he will raise the handle Q.
  • Said additional means comprises screw threaded bolts S extending through an aperture provided therefor in handle Q, said bolt being attached loosely at its upper end to worm wheel K, as by pin T, and adjustable nuts u on said bolt S.
  • the position of said pin T (which is rotatable) relative to the cam J is indicated by the broken lines T in Fig. While the worm gear K is turning clockwise and bringing the link I and jaw F down, the pin T is being moved up and is carrying therewith bolt S, and the nuts u are adjusted on said bolt S so that the said upward movement of the bolt brings said nut into contact with the under side of said handle, (to raise it to its normal and neutral position, with said clutch P out of gear), when the grasping or holding bar G is in its desired downward position.
  • the mechanism which is positioned at the farther end of the brake illustrated in Fig. 1 is provided with members corresponding with the members illustrated in Figs. 1 and 2 and the description hereinbefore given applies to said duplicate or corresponding mechanism.
  • a power driven device to control the movement of the movable jaw of a brake, the combination of a driving and a driven shaft, clutches loosely mounted on said driven shaft, means on said driving shaft engaging with means on said driven shaft to turn said clutches in opposite directions, an additional clutch mounted on said driven shaft to turn therewith and longitudinally movable thereon, a handle adapted to move said additional clutch to alternately engage with said first named clutches, an eccentric, a link attached at one end to said movable jaw and mounted at the other end on said eccentric, and means connecting said driven shaft and said eccentric to communicate swinging movement to said eccentric by the rotation of said driven shaft in opposite directions.
  • a power driven device to controi the movement of the movable jaw of a brake, the combination of a driving and a driven shaft, clutches loosely mounted on said driven shaft, means on said driving shaft engaging with means on said driven shaft to turn said clutches in opposite directions, an additional clutch mounted on said driven shaft to turn therewith and longitudinally movable thereon, a handle adapted to move said additional clutch to alternately engage with said first named clutches, an eccentric, a link attached at one end to said movable jaw and mounted at the other end on said eccentric, and means cona rotatable shaft, mounted in journals on said standard, and a handle also mounted on said standard, a worm and a clutch mounted on said shaft to turn therewith, said clutch longitudinally movable, and arranged to move and to be moved by said handle, gear, wheels loosely mounted on said shaft and clutch wheels attached to said gear wheels, a driven shaft rotatably mounted on said standard, a gear wheel on said driven shaft arranged to rotate said loosely mounted gears and clutch
  • a brake In a brake, a standard, a movable jaw and an eccentric mounted on said standard, in combination with a link connected at one end to said movable j aw and at the other end arranged to engage with said eccentric, means comprising a clutch member movable from a neutral to operative positions to turn said eccentric in opposite directions, and a plurality of means to limit said turning, one of said limiting means comprising mechanism to automatically force said movable clutch member from an operative into a neutral position, and the other comprising engageable faces on said movable clutch member so disposed as to automatically disengage when more than a predetermined load is presented thereto.
  • a cam to control the movement of the movable jaw of a brake
  • a link pivotally attached at one end to said jaw and arranged to engage with said cam
  • means to turn said cam in opposite directions a handle provided with an aperture
  • a bolt extending through said aperture in said handle, a connection between the upper end of said bolt and said cam, and nuts adjustably mounted on said bolt and adapted to be forced on to said handle, to move said handle when said cam is moved into predetermined positions.

Description

N. KRUMP.
SHEET METAL BRAKE.
APP. L!CAT|0N FILED SEPT. a. 1915.
1 ,203,206 Patented Oct. 31, 1916.
2 SHEETS-SHEET 1.
Arrak/vzx Mm PETERS ca, PNOm-LHNCL. WASNINCIDH. n. L
N. KRUMP.
SHEET METAL BRAKE.
APPLICATION men SEPT. 3, 1915.
1,203,206. Patented Oct. 31,1916.
2 SHEETS-SHEET 2.
I5 Air/v5.55
/M/V)LU? J Xrrazmrr NIG KRUMP, OF CHICAGO, ILLINOIS.
SHEET-METAL BRAKE.
Specification of Letters Patent.
4 Patented Oct. 31, 1916.
Application filed September 3, 1915. Serial No. 48,927.
To all whom it may concern:
Be it known that I, N10 KRUMP, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sheet-Metal Brakes, of which the following is a specification.
This invention relates to devices for bending sheet metal and used by sheet metal workers, and known in the sheet metal art as brakes.
The object of this invention is to obtain a sheet metal brake which is adapted to bend sheets of metal of various thickness; to obtain a device in which sheets of metal will be held firmly and bent on a determined line; and to obtain a power driven device of the kind named wherein a sheet holding mechanism, while adapted to be applied to hold a sheet of metal rigidly in place, will not be broken bythe lack of skill or inatten tion of the person or persons operating the same. And a'further object is to obtain a holding mechanism in a brake of the character described which may be set, so that when a large number of sheets of metal of the same thickness are to be bent the said holding mechanism will be automatically disconnected from the motive power which is applied thereto to obtain a desired grasp or hold on the sheet of metal which is to be bent.
In bending the edge of a sheet or strip of metal of considerable length, say one exceeding nine or ten feet, I find it desirable to be able to independently control the holding mechanism at the ends of said sheet or strip, so that when the said sheet or strip is properly in place at one of its ends said end can be held, while the other end is moved a short distance to the proper position for said bend. In operating a device I find it desirable to provide means whereby what may be termed an automatically controlled grasp by said holding means, at one end of said sheet, may be applied thereto, said automatic grasp being such as to permit movement of the sheet of metal at the other end.
In the drawings referred to as forming a part of this specification, Figure 1, is a perspective of a brake provided with holding mechanism embodying this invention. Fig. 2 is an end view of said brake, showing a mechanism embodying this invention thereon, witha portion of a worm driven wheel which forms an element of said mechanism removed, to xpose to view a cam and a cam shaft, which are also elements of the mechanism. Fig. 3 is a vertical sectional View of a link, cam and worm wheel and a side elevation of the shafts thereof, said section being taken on line 3-3 of Fig. 2 and viewed in the direction indicated by the arrows. Fig. 4 is a front View of said link. Fig. 5 is an end elevation of a clutch sleeve forming an element of mechanism embodying the invention. And Fig. 6 is a side elevation of said clutch sleeve.
A reference character applied to designate a given part indicates said part throughout the several figures of the drawing wherever the same appears.
A, A represent standards forming the ends of the brake.
B, Fig. 2, is a table on which sheets of metal to be bent may be laid.
C is an apron which is turned on shaft D; and E (Fig. 1), is an angle-iron which is rigidly secured to the upper edge of the apron C, and by means of which a sheet of metal which is placed on table l3 and held rigidly thereto, by the mechanisms embodying this invention, is bent.
F is a movable body which is mounted to rock on shaft f in slot f forming the upper jaw of the clamp of the brake, andsaid upper jaw is provided at the forward and holding edge thereof with the holding or grasping plate G.
The sheet of metal to be bent is placed on table B and is brought out in front of the holding plate G and rigidly held by said plate G as apron C and angle iron E are turned on shafts D, and said angle iron E bends said sheet.
The mechanism by means of which the upper jaw F and holding or grasping plate G are moved, to raise said plate G from, and bring it to, a sheet or strip of metal which is to be held thereby and bent by apron C and angle iron E, embodies this invention. Said mechanisms are positioned on standard A, at both ends thereof, and are duplicates (but may be rights and lefts) and each of said mechanisms comprises the following described parts.
H represents a shaft which is secured to standard A; it represents a spur shaft which is secured to the upper jaw F.
I I represents a link, J a cam and K a worm wheel.
L, L L represent shafts journaled in bearings M, and M M and M and M respectively.
L represents a driving shaft which is journaled in suitable bearing on standards A A, and N a beveled gear, which is rigidly secured to driving shaft L n represents a beveled gear intermeshing, with gear N. Beveled gear a and gear a are connected or joined to turn in unison, and are mounted loosely on shaft L.
N and a represent gears which are rigidly secured on shaft L to turn therewith.
N is a gear wheel on shaft L and N is a gear wheel which is loosely mounted on shaft L. Gears 719, N intermesh; and also gears W, N and N a is a worm wheel which is secured on keyed on shaft L to turn therewith while longitudinally movable thereon; said longitudinal movement being controlled by the handle Q which is pivoted to standard A at Q. The clutch wheel P is provided with the groove 19, in which said handle Q fits and with the clutch teeth p and 10 R is a clutch wheel rigidly secured to the gear wheel a to turn therewith and r is a clutch wheel which is rigidly secured to the gear wheel N to turn therewith.
The handle Q is moved down to force the clutch P into gear with clutch R, and bring the holding bar G of the upper jaw F down into holding or grasping position on a sheet of metal on tableB; and said handle is moved up to force said clutch P into gear with clutch 7 to raise said holding bar G from said grasping position. The clutches R and r, turning in opposite directions, as hereinbefore described, enable me to move the grasping bar G down and up the required distance to operate it, by rocking said worm gear wheel K and cam J on their shaft. That is, they are not rotated or caused to turn a complete revolution. When the handle Q is moved down from the position illustrated in Fig. 2, the clutch teeth 79 on clutch P, are forced into engagement with the teeth of clutch wheel R and when said handle is moved up from said illustrated position the clutch teeth p are moved into engagement with the teeth of clutch wheel 7*. I
Sheets or strips of metal of different thicknesses are bent or folded on the brake illustrated, and to prevent breaking of the mechanism embodying this invention, (when said holder is pressing with determined force on the sheet or strip of metal thereunder), the engaging faces of the clutch teeth 32 and the teeth on clutch R are made of such shape that the same can not be held in engagement, by a person grasping the handle Q, after a predetermined pressure of bar G is obtained said handle being forced upward by said engaging faces. Of course, upon the handle Q being forced up as aforesaid, the person holding it down and feeling the upward movement thereof, will not resist the same; on the contrary being thereby notified or warned, he will raise the handle Q. However, if said engaging faces are at substantially an angle of about 45 degrees from a plane at right angles to shaft L the above named results are obtained, and breaking of the device is obviated. Grasping bar or plate G being down and the handle Q in its normal position (as illustrated in Fig. 2), to release and raise said grasping bar the handle Q is raised to engage clutch P with the teeth of clutch r, and to obtain quick release of said engagement 1 make the engaging faces of the teeth on said clutches at the same angle as those of clutch R and teeth 32 In addition to the above named means for automatically throwing the clutch wheel P out of engagement withclutch R, I provide additional automatic means for throwing said clutch out of engagement, on the downward movement of the upper jaw, when it has reached a desired downward position. Said additional means comprises screw threaded bolts S extending through an aperture provided therefor in handle Q, said bolt being attached loosely at its upper end to worm wheel K, as by pin T, and adjustable nuts u on said bolt S. The position of said pin T (which is rotatable) relative to the cam J is indicated by the broken lines T in Fig. While the worm gear K is turning clockwise and bringing the link I and jaw F down, the pin T is being moved up and is carrying therewith bolt S, and the nuts u are adjusted on said bolt S so that the said upward movement of the bolt brings said nut into contact with the under side of said handle, (to raise it to its normal and neutral position, with said clutch P out of gear), when the grasping or holding bar G is in its desired downward position.
It will be observed that when the handle Q is raised to bring the teeth 72 of clutch P into engagement with clutch wheel 9" the direction of revolution of worm n is reversed so that the worm gear wheel K turns in a direction contrary to the movement of the hands of a clock and thereby the bolt S is moved downward, and U are nuts on bolt S which are adjusted on saidbolt to come in contact with the upper face of handle Q and force said handle down thereby breaking the engagement of clutches P and R when cam J has raised said jaw F a predetermined distance.
The contact faces of the teeth of clutch hereinbefore stated, at an angle (about 4:5
degrees) to the face of a disk on the shaft L, constitute a sliding engagement; that is, as against sufiicient resistance the said contact faces will slide upon-each other and move the handle Q as said clutches move out of engagement; In addition to this, said faces being sliding faces it is necessary for the person controlling the position of clutch P to retain hold of handle Q, at all times, and when said clutches P and r are in engagement handle Q can be easily moved downward by the operator, as the contact faces of the teeth on clutch 1" do not grip or hold in the manner in which the same would grip or hold if said contact faces were in a plane radial to shaft L.
The mechanism which is positioned at the farther end of the brake illustrated in Fig. 1 is provided with members corresponding with the members illustrated in Figs. 1 and 2 and the description hereinbefore given applies to said duplicate or corresponding mechanism.
I claim 1. In a power driven device, to control the movement of the movable jaw of a brake, the combination of a driving and a driven shaft, clutches loosely mounted on said driven shaft, means on said driving shaft engaging with means on said driven shaft to turn said clutches in opposite directions, an additional clutch mounted on said driven shaft to turn therewith and longitudinally movable thereon, a handle adapted to move said additional clutch to alternately engage with said first named clutches, an eccentric, a link attached at one end to said movable jaw and mounted at the other end on said eccentric, and means connecting said driven shaft and said eccentric to communicate swinging movement to said eccentric by the rotation of said driven shaft in opposite directions.
2. In a power driven device, to controi the movement of the movable jaw of a brake, the combination of a driving and a driven shaft, clutches loosely mounted on said driven shaft, means on said driving shaft engaging with means on said driven shaft to turn said clutches in opposite directions, an additional clutch mounted on said driven shaft to turn therewith and longitudinally movable thereon, a handle adapted to move said additional clutch to alternately engage with said first named clutches, an eccentric, a link attached at one end to said movable jaw and mounted at the other end on said eccentric, and means cona rotatable shaft, mounted in journals on said standard, and a handle also mounted on said standard, a worm and a clutch mounted on said shaft to turn therewith, said clutch longitudinally movable, and arranged to move and to be moved by said handle, gear, wheels loosely mounted on said shaft and clutch wheels attached to said gear wheels, a driven shaft rotatably mounted on said standard, a gear wheel on said driven shaft arranged to rotate said loosely mounted gears and clutches in opposite directions by the rotation of said driving shaft, in combination with a worm wheel, an eccentric joined thereto, said worm wheel mounted on said standard with its teeth engaging with said worm, and a link attached at one end to said movable jaw and at the other end arranged to engage with said eccentric.
4-. In a brake, a standard, a movable jaw and an eccentric mounted on said standard, in combination with a link connected at one end to said movable j aw and at the other end arranged to engage with said eccentric, means comprising a clutch member movable from a neutral to operative positions to turn said eccentric in opposite directions, and a plurality of means to limit said turning, one of said limiting means comprising mechanism to automatically force said movable clutch member from an operative into a neutral position, and the other comprising engageable faces on said movable clutch member so disposed as to automatically disengage when more than a predetermined load is presented thereto.
5. In a power driven device to control the movement of the movable jaw of a brake, a cam, a link pivotally attached at one end to said jaw and arranged to engage with said cam, means to turn said cam in opposite directions, a handle provided with an aperture, a bolt extending through said aperture in said handle, a connection between the upper end of said bolt and said cam, and nuts adjustably mounted on said bolt and adapted to be forced on to said handle, to move said handle when said cam is moved into predetermined positions.
NIO KRUMP.
In the presence of II. C. DREIS,
CHARLES TURNER Brown.
Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.
US4892715A 1915-09-03 1915-09-03 Sheet-metal brake. Expired - Lifetime US1203206A (en)

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