US3106464A - Glass sheet bending apparatus - Google Patents
Glass sheet bending apparatus Download PDFInfo
- Publication number
- US3106464A US3106464A US793900A US79390059A US3106464A US 3106464 A US3106464 A US 3106464A US 793900 A US793900 A US 793900A US 79390059 A US79390059 A US 79390059A US 3106464 A US3106464 A US 3106464A
- Authority
- US
- United States
- Prior art keywords
- frame
- bending
- flexible
- sheet
- die
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000005452 bending Methods 0.000 title claims description 68
- 239000011521 glass Substances 0.000 title description 21
- 229920001169 thermoplastic Polymers 0.000 claims description 4
- 239000004416 thermosoftening plastic Substances 0.000 claims description 4
- 239000012530 fluid Substances 0.000 description 11
- 230000003014 reinforcing effect Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 230000000295 complement effect Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 239000002985 plastic film Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052729 chemical element Inorganic materials 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 235000015250 liver sausages Nutrition 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 230000000284 resting effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B23/00—Re-forming shaped glass
- C03B23/02—Re-forming glass sheets
- C03B23/023—Re-forming glass sheets by bending
- C03B23/03—Re-forming glass sheets by bending by press-bending between shaping moulds
- C03B23/031—Re-forming glass sheets by bending by press-bending between shaping moulds the glass sheets being in a vertical position
Definitions
- This invention relates to an apparatus for bending or curving plastic sheets, the apparatus being particularly adapted for the bending of sheets of glass presented thereto at the temperature necessary to their bending.
- the apparatus includes as essential elements thereof a rigid convex form or die and a flexible element, the sheet to be bent being interposed between the die and the element and being progressively bent as the die and element approach each other.
- the apparatus of the invention is particularly useful in the bending of safety glazings, such as Windshields for automobiles, which sometimes require bent glass sheets of shapes which existing bending apparatus cannot conveniently produce. This is especially true when the bent glass sheet includes parts which are curved cylindrioally and parts curved conically, and even parts having spherical curvatures.
- a flexible element made up of a frame formed of thin bands articulated at'their extremities.
- Such bands which are themselves flexible, may, by reason of such articulations, be displaced through small distances with respect to each other, thereby permitting the frame to yield as required to conform to the shape of the rigid convex die with which it cooperates.
- Such yieldability of the element allows it to adjust its shape as required by the die which may, for example, have different zones thereof having surfaces which are plane, cylindrical, conical, and various combinations thereof.
- the bands making up the element are reinforced by one or more additional bands.
- additional bands which may be in the nature of leaf springs, are permitted to slide in the directions of their lengths in stirrups which are preferably of such construction as to allow the bands to be held in fixed positions, as desired.
- the frame may be applied directly to the sheet to be bent but, particularly when the sheet is made of glass and is heated to an elevated temperature, the sheet-contacting members of the frame are preferably provided with a refractory covering which is deformable with the frame to the eventual shape to which the sheet'is to be bent.
- the frame may, in accordance with another illustrative embodiment, consist of a continuous flexible elastic member which is bent to form a closed frame, such continuous member being mounted on an articulated assembly having a shape corresponding to that of the sheet to be bent.
- the flexible frame is fixedly mounted at its middle on :a support and disposed opposite the die.
- Means are providedto move the die and frame relatively toward and away from each other so as to grip a sheet to be bent between them and progressively to bend the sheet asthe die and frame come together.
- the'extrernities of the frame are selectively formed and bent' by controllable means whereby to permit the frame to mate with the die.
- such frame-deforming means are fluid actuated pistons.
- the turning of such arms being controlled by fluid.
- FIG. 1 is a view in plan of a first embodiment of sheet bending apparatus in accordance with the invention
- FIG. 2 is a. view in elevation of the flexible bending taken along the line 2-2 of FIG. I;
- FIG. 3 is a fragmentary view in section of a portion of the sheet engaging frame member of the flexible ele ment
- FIG. 4 is a fragmentary view in elevation of a sheetengaging frame of the flexible element
- FIG. 5 is a view in vertical section through such flexible sheet engaging frame element, the section being taken along the line 5-5 of FIG. 1;
- FIG. 6 is :a view in plan of a second embodiment of sheet bending apparatus made in accordance with the invention.
- FIG. 7 is a view in elevation of the flexible element of the apparatus of FIG. 6, the element being shown in ex tended condition;
- FIG. 7a shows a detail in section of the flexible element
- FIG. 8 is a view elevation of a third embodiment of sheet bending apparatus in accordance with the invention.
- FIG. 9 is a view in plan of the apparatus of FIG. 8.
- FIG. 10 is a fragmentary view in plan on an enlarged scale of the portion of the apparatus of FIG. 9 at the end of one of the pivoted arms and of the end of the flexible frame member connected thereto.
- the flexible element 1 between which and a rigid convex die or bending form 2 a sheet of glass F is disposed to be bent, is made up of thin bands 4, 5, 6 and 7, made, for example, of sheet iron or steel.
- Form 2 a has a forward curved, glass-engaged surface and a rear, reinforcing web portion 50, as shown.
- Such bands are connected in a non-rigid manner at their extremities 3, 3', 3", and-3" as by rivets the heads of which only loosely engage the bands.
- the frame 1 is eventually provided with cross bands 8, 9, 10, and 11, extending between the opposed longer bordering bands 4 and 5 of the frame,
- the two longest bands 4 and 5 carry at the rear thereof at least one, and preferably a plurality of, additional bands 12 whichfunction as leaf springs.
- additional bands 12 slide to a limited extent in stirrup-like members 13 which are shown more Patented Oct. 8, 1963 I 3 threaded member 13a having an inwardly disposed head 13b, whereby the additional band 12 may be locked in a desired position or may be allowed to slide longitudinally with a desired degree of frictional restraint.
- reinforcing elements 14 and 14 which extend through stirrup-like members in the same manner as do bands 12.
- Such reinforcing bands 14 and 14' facilitate the bending of the ends of the sheet P which, in the embodiments shown, are to lie substantially in planes, designated 15 and 15, on the ends of die 2.
- the extremities of the frame are reinforced by auxiliary bands 16, 16, 17, and 17.
- Such latter auxiliary bands serve to support at such ends of the frame a continuous ribbon 18 of refractory material which contacts the sheet of glass during the course of the bending operation.
- FIGS. 4 and 5 show the ribbon 18 as being made up of a flexible band 19 and by a refractory facing 20.
- the band 19 is held between opposed jaws 21 and 21 of a sheet iron clip, such clip being riveted to the frame at 22 and 22.
- the frame is secured at each of its ends 23 and 24 by connecting means 25 and 26 t0 the ends of the piston rods of the respective prime movers shown as fluid operated motors 27 and 28.
- fluid operated motors have the ends of the casings or cylinders thereof pivotally mounted on a transverse frame member 29 which is rigidly secured to central supports 30 and 30a.
- the sheet of glass P which is to be bent is heated near to softening and is supported, by means not shown, in vertical position between the frame 1 and the die 2 with the two such members retracted from each other as shown in FIG. 1. Following this, the elements 1 and 2 are caused to approach each other.
- member 30 carrying the flexible bending frame is fixedly mounted, whereas die 2 is mounted for reciprocation toward and away from the flexible frame.
- the element 51 is a piston rod having a piston 70 connected thereto.
- the piston and piston rod are parts of a horizontally disposed double acting fluid motor having a cylinder designated 71. With the parts in the position shown in FIG. 1, piston 70 and rod 51 are advanced to the left carrying with it the glass sheet F and causing the sheet to contact the flexible ribbon 18.
- Such contact of the sheet of glass by the ribbon 18 first occurs in its central or median zone at support 30a, and also presses such central zone of the sheet against the die 2.
- the frame 1 and die 2 continue to approach each other, the sheet of glass F is progressively bent and applied to the die, the frame 1 yielding to allow it also to assume a form complementary to the die.
- FIGS. 6, 7, and 7 there is shown a second embodiment of sheet bending apparatus in accordance with the invention.
- the flexible frame is made up of a continuous flexible member 31 closed on itself which is bent to form an open frame generally of the shape of the sheet blank which is to be bent.
- Frame member 31 is secured in its central position 31a to an axial support 32.
- the member 31 is composed of a central helical spring 34 which is provided with a heat resistant sheath 33 which may be made, for example, of flexible refractory plastic material or of any other suitable material.
- Arms 35 and 36 are fastened on support 32. At the ends of the arms 35 and 36 there are pivotally connected links 37 and 38, the opposite ends of which are connected to vertical frame members 39 and 40.
- Pivotally supported on a transverse frame member aflixed to central support 32 are the cylinders of two prime movers shown as fluid operated motors 43 and 44.
- the piston rods 41 and 42, respectively, of such motors are pivotally connected to links 37 and 38 secured, respectively, to vertical frame members 39 and 40.
- the frame member 31 is held between the frame members 39 and 40 by means such as brackets 39a, 39b, 40a, and 40b.
- Frame member 31 is provided with retractors or braces 46, 47, 48 and 49 which are adjustable to vary the shape of the frame in accordance with contour of the sheet which is to be bent.
- the frame member 31 may be deformed so as to be applied effectively to the surface of the convex die 50.
- the piston rods 41 and 42 are fully retracted within their respective cylinders 43 and 44, so that the elastic frame 31, under the action of arms 37 and 38, lies substantially in the vertical plane of its median or central position 31a.
- the frame 31 has been first applied to the rigid convex die 50, with a sheet F to be bent between the frame 31 and the die 50, the frame and die first contact the central portion of sheet F. Thereafter the frame begins to bend the sheet around die in directions extending oppositely from the central vertical transverse plane thereof.
- FIGS. 8, 9, and 10 The third disclosed embodiment of the sheet bending apparatus of the invention is shown in FIGS. 8, 9, and 10.
- Such apparatus is particularly useful for bending sheets thereby into the so-called panoramic form.
- Such apparatus includes a support 51 which carries a rigid convex die 52, and a support 53 which is in alignment with and opposite the support 51.
- Support 53 carries a flexible "bending frame 55.
- Such frame is rigidly mounted at its center on the support 53 and at its ends is yieldably connected to the outer ends of two curved arms 54 and 54' which are pivotally mounted on vertical pivot pins secured to central support 53.
- the arms 54 or 54' are under the control of fluid operated motors 57 and 57', the rear ends of the casings or cylinders of which are pivotally supported on a transverse frame member 58 which is secured to support member 53.
- the outer ends of piston rods 56 of motors 57 and 57' are pivotally connected to the respective arms 54 and 54', intermediate the lengths thereof.
- the flexible frame 55 and the die 52 are caused to approach each other and to grip sheet 59 between the rigid central position of frame 55 at support 53 and the central portion of die 52.
- Continued approach of the frame and die toward each other causes the frame to be bent to conform to the gently curving portions of die 53 lying on opposite sides of the central zone thereof.
- the fluid actuated motors 57 and 57 are actuated to thrust the piston rods outwardly therefrom.
- an angularly disposed passage in a boss 60 Within which an elongated pin 61 is slida-bly mounted.
- Such pin carries at its lower end an articulated element 63, which is connected to the end of frame 55 by a bracket 64.
- a coil compression spring 65 is disposed between element 65- and the boss 60 on arm 54. Such coil spring maintains the frame 55 under tension at the beginning of the bending operation, and yields to compensate for the difference in length between the arc and the chord of the path of the end of the arm during bending.
- pins 66, 66' which extend through a flange on the respective one of the arms 54 and 54'.
- the inner ends of pins 66 engage the rear surface of frame 55 and thrust it strongly against glasssheet 59; such sheet in turn is thrust in the opposite direction by die 52.
- Pins 66 are preferably adjustable along their axes on the respective arms 54 and 54, as by having screw threaded engagement with the flange on the arm through which they pass.
- Apparatus for bending heated thermoplastic sheets such as glass and the like comprising a convex, rigid bending form and a flexible bending form each having a heat resistant sheet engaging face, said forms being mounted in opposing cooperating position to engage the opposite broad surfaces of a thermoplastic sheet and to bend said sheet between them, a central support for the flexible form, means to advance the forms toward each other, said flexible bending for-m having a flexible bending frame fixedly mounted in its central portion on said support, and means selectively to produce deformation of the ends of the flexible bending frame to permit them to conform to the curvature of the zones of the rigid bending form cooperating therewith as the bending operation progresses.
- Apparatus as defined in claim 2 comprising oppositely disposed arms pivotally mounted on said central support, the ends of the flexible bending frame being secured to the outer ends of said arms, and means for thrusting the arms to cause the outer ends thereof to move closer together andpartially to wrap the ends of the flexible bending frame around the opposite ends of the rigid bending form toward the end of the sheet-bending operation.
- Apparatus as defined in claim 3 comprising resilient means attaching the ends of the frame to the ends of the arms, said resilient means allowing the ends of the frame to yield relative to the arms as the bending operation progresses.
- Apparatus as defined in claim 5, comprising a plurality of adjustable abutment means mounted on the forward faces of the arms, said abutment means engaging the rear edge of the flexible frame when the frame lies partially wrapped about the rigid'convex bending form.
- Apparatus as defined in claim 10 comprising reinforcing leaf springs aligned with and lying alongside the backs of the flexible bands of the flexible bending frame and slidably connected thereto.
- Apparatus as defined in claim 11, comprising stirrup-like clips attached to the flexible bands, said reinforcing leaf springs being slidable in said clips.
- the flexible sheet-engaging frame is a continuous flexible sheetengaging member closed onitself and generally conforming to the outline of the sheet to be bent.
- Apparatus as defined in claim 14, comprising a flexible refractory sheet-engaging facing on the flexible bending frame.
- the continuous flexible sheet-engaging member comprises an elongated coil spring extending centrally therewithin and a heat resistant sheath disposed about said spring.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
- Joining Of Glass To Other Materials (AREA)
- Shaping Of Tube Ends By Bending Or Straightening (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR758493A FR1215559A (fr) | 1958-02-18 | 1958-02-18 | Dispositif de bombage de feuilles en matière thermoplastique, notamment en verre |
Publications (1)
Publication Number | Publication Date |
---|---|
US3106464A true US3106464A (en) | 1963-10-08 |
Family
ID=8705773
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US793900A Expired - Lifetime US3106464A (en) | 1958-02-18 | 1959-02-17 | Glass sheet bending apparatus |
Country Status (7)
Country | Link |
---|---|
US (1) | US3106464A (it) |
CH (1) | CH354208A (it) |
DE (1) | DE1109842B (it) |
ES (1) | ES247299A1 (it) |
FR (1) | FR1215559A (it) |
GB (1) | GB913154A (it) |
NL (1) | NL236203A (it) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4277276A (en) * | 1980-03-17 | 1981-07-07 | Ppg Industries, Inc. | Method and apparatus for shaping glass sheets using deformable vacuum mold |
US4297118A (en) * | 1980-03-18 | 1981-10-27 | Ppg Industries, Inc. | Controlling overheating of vacuum mold used to shape glass sheets |
US4349375A (en) * | 1980-03-18 | 1982-09-14 | Ppg Industries, Inc. | Deformable vacuum mold for shaping glass sheets |
US5695538A (en) * | 1994-07-15 | 1997-12-09 | Ppg Industries, Inc. | Flexible press and method of use |
US5849056A (en) * | 1995-12-11 | 1998-12-15 | Ppg Industries, Inc. | Electrically activated flexible press for shaping heat softenable sheet material |
CN110668683A (zh) * | 2018-07-03 | 2020-01-10 | 定西中庆玄和玻璃科技有限公司 | 一种用于玻璃弯曲钢化的弹性固定装置 |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL276398A (it) * | 1961-03-27 | |||
US4056379A (en) | 1977-01-03 | 1977-11-01 | Ppg Industries, Inc. | Forming V bends in glass sheets by press bending |
DE2741965C3 (de) * | 1977-09-17 | 1980-07-24 | Vereinigte Glaswerke Gmbh, 5100 Aachen | Verfahren und Vorrichtung zum Biegen von Glasscheiben |
US4289520A (en) * | 1979-12-17 | 1981-09-15 | Advanced Glass Systems Corporation | Method and apparatus for bending glass sheets |
US4361433A (en) * | 1981-03-24 | 1982-11-30 | Advanced Glass Systems Corp. | Method of bending a glass sheet |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US305707A (en) * | 1884-09-23 | Machine for forming springs | ||
US760959A (en) * | 1903-07-20 | 1904-05-24 | American Glass Bending Company Ltd | Apparatus for bending glass. |
US1906392A (en) * | 1930-11-03 | 1933-05-02 | Harry S Mcleod | Process of bending wood |
FR845786A (fr) * | 1938-05-06 | 1939-09-01 | Cie Reunies Glaces Et Verres | Dispositif conformateur de feuilles courbes de verre ou autres matières notamment en vue de la trempe, et installations en comportant appli cation |
US2297315A (en) * | 1941-03-28 | 1942-09-29 | Pittsburgh Plate Glass Co | Apparatus to produce bent glass |
US2350915A (en) * | 1942-04-13 | 1944-06-06 | Wurlitzer Co | Apparatus for forming panels |
US2382807A (en) * | 1942-09-21 | 1945-08-14 | Seeger Refrigerator Co | Method and apparatus for bending sheet material |
US2434379A (en) * | 1944-12-16 | 1948-01-13 | Glenn L Martin Co | Apparatus and method of stretch pressing metal sheets |
US2663974A (en) * | 1951-07-23 | 1953-12-29 | Motor Products Corp | Apparatus for bending glass sheets |
FR1112708A (fr) * | 1954-07-08 | 1956-03-19 | Saint Gobain | Procédé et dispositifs pour bomber les feuilles de verre |
CA541626A (en) * | 1957-05-28 | Pilkington Brothers Limited | Methods of and apparatus for bending sheets of glass |
-
0
- NL NL236203D patent/NL236203A/xx unknown
-
1958
- 1958-02-18 FR FR758493A patent/FR1215559A/fr not_active Expired
-
1959
- 1959-02-17 ES ES0247299A patent/ES247299A1/es not_active Expired
- 1959-02-17 DE DES61795A patent/DE1109842B/de active Pending
- 1959-02-17 CH CH354208D patent/CH354208A/fr unknown
- 1959-02-17 US US793900A patent/US3106464A/en not_active Expired - Lifetime
- 1959-02-18 GB GB5679/59A patent/GB913154A/en not_active Expired
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US305707A (en) * | 1884-09-23 | Machine for forming springs | ||
CA541626A (en) * | 1957-05-28 | Pilkington Brothers Limited | Methods of and apparatus for bending sheets of glass | |
US760959A (en) * | 1903-07-20 | 1904-05-24 | American Glass Bending Company Ltd | Apparatus for bending glass. |
US1906392A (en) * | 1930-11-03 | 1933-05-02 | Harry S Mcleod | Process of bending wood |
FR845786A (fr) * | 1938-05-06 | 1939-09-01 | Cie Reunies Glaces Et Verres | Dispositif conformateur de feuilles courbes de verre ou autres matières notamment en vue de la trempe, et installations en comportant appli cation |
US2297315A (en) * | 1941-03-28 | 1942-09-29 | Pittsburgh Plate Glass Co | Apparatus to produce bent glass |
US2350915A (en) * | 1942-04-13 | 1944-06-06 | Wurlitzer Co | Apparatus for forming panels |
US2382807A (en) * | 1942-09-21 | 1945-08-14 | Seeger Refrigerator Co | Method and apparatus for bending sheet material |
US2434379A (en) * | 1944-12-16 | 1948-01-13 | Glenn L Martin Co | Apparatus and method of stretch pressing metal sheets |
US2663974A (en) * | 1951-07-23 | 1953-12-29 | Motor Products Corp | Apparatus for bending glass sheets |
FR1112708A (fr) * | 1954-07-08 | 1956-03-19 | Saint Gobain | Procédé et dispositifs pour bomber les feuilles de verre |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4277276A (en) * | 1980-03-17 | 1981-07-07 | Ppg Industries, Inc. | Method and apparatus for shaping glass sheets using deformable vacuum mold |
US4297118A (en) * | 1980-03-18 | 1981-10-27 | Ppg Industries, Inc. | Controlling overheating of vacuum mold used to shape glass sheets |
US4349375A (en) * | 1980-03-18 | 1982-09-14 | Ppg Industries, Inc. | Deformable vacuum mold for shaping glass sheets |
US5695538A (en) * | 1994-07-15 | 1997-12-09 | Ppg Industries, Inc. | Flexible press and method of use |
US5849056A (en) * | 1995-12-11 | 1998-12-15 | Ppg Industries, Inc. | Electrically activated flexible press for shaping heat softenable sheet material |
CN110668683A (zh) * | 2018-07-03 | 2020-01-10 | 定西中庆玄和玻璃科技有限公司 | 一种用于玻璃弯曲钢化的弹性固定装置 |
Also Published As
Publication number | Publication date |
---|---|
FR1215559A (fr) | 1960-04-19 |
NL236203A (it) | |
ES247299A1 (es) | 1959-06-01 |
CH354208A (fr) | 1961-05-15 |
GB913154A (en) | 1962-12-19 |
DE1109842B (de) | 1961-06-29 |
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