EP0775538B1 - Pipe bending apparatus with hydraulic transmission - Google Patents
Pipe bending apparatus with hydraulic transmission Download PDFInfo
- Publication number
- EP0775538B1 EP0775538B1 EP96117812A EP96117812A EP0775538B1 EP 0775538 B1 EP0775538 B1 EP 0775538B1 EP 96117812 A EP96117812 A EP 96117812A EP 96117812 A EP96117812 A EP 96117812A EP 0775538 B1 EP0775538 B1 EP 0775538B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- chamber
- reservoir
- cylinder
- rod
- conduit
- 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
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D7/00—Bending rods, profiles, or tubes
- B21D7/06—Bending rods, profiles, or tubes in press brakes or between rams and anvils or abutments; Pliers with forming dies
- B21D7/063—Pliers with forming dies
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B7/00—Pliers; Other hand-held gripping tools with jaws on pivoted limbs; Details applicable generally to pivoted-limb hand tools
- B25B7/12—Pliers; Other hand-held gripping tools with jaws on pivoted limbs; Details applicable generally to pivoted-limb hand tools involving special transmission means between the handles and the jaws, e.g. toggle levers, gears
- B25B7/126—Pliers; Other hand-held gripping tools with jaws on pivoted limbs; Details applicable generally to pivoted-limb hand tools involving special transmission means between the handles and the jaws, e.g. toggle levers, gears with fluid drive
Definitions
- This invention relates to a pipe bending apparatus with hydraulic transmission, operable with one hand, in accordance with the precharacterising part of the main claim.
- Apparatus of this type have been known for some time (see for example Italian utility model 207711 (& EP-A-0 220 639) in the name of the present applicant). Although such apparatus provide acceptable operation they present certain drawbacks.
- the first of these is the fact that the deformable wall of the reservoir containing the fluid for the hydraulic circuit undergoes relatively large deformation, leading to its breakage or imperfect sealing, in this latter case air bubbles possibly entering the reservoir to cause maloperation of the hydraulic circuit. It has also been found experimentally that dirt tends to accumulate in the open front part of the cylinder with the passage of time, making the movement of the rod more difficult and possibly cause it to seize.
- An object of the present invention is to provide a pipe bending apparatus of hydraulic transmission type, operable with one hand, which obviates the aforesaid drawbacks and in particular reduces the deformation of the deformable wall of the reservoir for the hydraulic circuit fluid.
- a further object is to provide an apparatus in which the possibility of air bubbles entering the apparatus hydraulic circuit is limited.
- the reference numeral 1 indicates a die-carrying rod
- 2 indicates elastic means forming a return element, such as a spring
- 3 indicates the inner end of the rod 1, provided with a gasket 4 for its sealing and slidable within the cylinder 5.
- the reference numeral 6 indicates the outer part of the apparatus handgrip, indicated overall by 7, said part 6 consisting of a tubular element concentric to the cylinder 5 and having its two ends sealedly fixed to a cap 8 and to the apparatus body 9.
- the body 9 is advantageously formed integral with the remaining lower part, indicated overall by 10.
- the reference numeral 11 indicates a cavity provided in the lower part of the body 10, forming a reservoir for oil or another suitable incompressible fluid (oil distribution within the apparatus is represented by grey shading in the figures).
- the reference numeral 12 indicates a cup-shaped elastic membrane, for example of rubber, plastic or another suitable material, which is fixed in position and sealed by a cup-shaped closure plug 13 comprising a vent hole 34.
- a support for an element 15 carrying the counter-die 16 the element 15 being connected removably to the body 10 to allow rapid and easy replacement of the die-carrier assembly.
- the reference numeral 21 indicates an interspace between the cylinder 5 and the piece 6 to allow the oil to pass in either direction, depending on whether the apparatus rod 1 is advancing, or returning under the action of the spring 2, the work having been completed.
- a non-return valve 22, of ball type, enables the oil to pass from the reservoir 11 to the chamber 23.
- the valve 22 is connected to a dip tube 60 in the centre of the reservoir 11. In this manner, even if air bubbles were to appear in the reservoir, they would not enter the hydraulic circuit of the apparatus. In this respect, whatever the inclination of the apparatus, the air bubbles would collect along the reservoir walls but never at its centre, and hence cannot enter the circuit.
- a second non-return valve 24 enables oil to flow from the chamber 23 to the interspace 21.
- the interspace 21 is hydraulically connected to the chamber 23 and to the chamber 43 defined by the walls of the cylinder sleeve and the gasket on the rod 1, by way of passages 40 provided within the sleeve.
- the reference numeral 25 indicates a plunger free to slide axially within a cylindrical guide bush 26 which carries at that end facing the chamber 23 an annular gasket 27 sealing against the plunger 25.
- a counteracting spring 29 is engaged in a support seat 28 provided on the end of the plunger 25 and acts against a shoulder formed at the end of the chamber 23.
- the reference numeral 30 indicates a ball interposed between the end of the plunger 25 and the lever arm 31, said lever arm being pivoted on the pin 32.
- the cylinder 5 is sealed by an element 50 which engages the body 9.
- an element 50 which engages the body 9.
- three usual annular gaskets 51 are provided.
- the element 50 together with the cylinder 5 and the gasket 4 of the rod 1 define a second chamber 52 connected to the reservoir 11 via a conduit divided into two mutually perpendicular portions 53A and 53B.
- the chamber 52 is also connected to the outside via a third conduit 54 ( Figure 2).
- the conduit portion 53A extends beyond the perpendicular portion 53B by a conduit portion 56 connected to the chamber 24 and acting together with the portion 53A as a return tube between this latter chamber and the reservoir 11.
- the threaded shank 39 of an interception means in the form of a cock consisting of a manually operable external handwheel 38 acts on the ball 41 to close or open the passage 36.
- the apparatus is gripped by one hand, which embraces the handgrip 7 and the lever 31.
- the oil finds the cock closed, so that it is obliged to enter the interspace 21 and then the chamber 43, where it acts against the end 3 of the rod 1, causing it to advance an initial distance against the action of the spring 2.
- the apparatus is in this manner again ready for a new pumping cycle.
- Each pumping cycle results in advancement of the rod 1, on which there is mounted a die of adequate size for the pipe to be bent, the die gradually approaching the corresponding counter-dies 16 to progressively bend the interposed pipe.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Bending Of Plates, Rods, And Pipes (AREA)
- Fluid-Pressure Circuits (AREA)
- Supply Devices, Intensifiers, Converters, And Telemotors (AREA)
Abstract
Description
Claims (6)
- A pipe bending apparatus with hydraulic transmission, operable with one hand, of the type comprising a cylinder (5, 8, 50, 6) in which there is movable in both directions a die-carrying rod (1) comprising - fixed in correspondence with that (3) of its ends located within the cylinder - a seal element (4) defining together with a first portion of the walls of said cylinder a first incompressible fluid containing chamber (43) of volume variable in relation to the movements of said rod, said first chamber being connected, via a delivery conduit (21) and return conduits (36, 56) and at least one intermediate chamber (23), to a reservoir (11) containing the incompressible fluid, so as to form a closed circuit; said intermediate chamber (22, 23, 24) comprising a hydraulic pump (25, 31) operable by one hand, and unidirectional valve means (22, 24); said return conduit (56) comprising manually operable interception means; said reservoir (11) comprising an at least partly deformable sealing wall (12), said cylinder comprising elastic means (2) arranged to return the rod to its rest position when said interception means is open; characterised in that said seal element (4) defines together with a second portion of the walls of said cylinder (50, 5, 6, 8) a second incompressible fluid containing chamber (52), said first and second chambers being sealedly separated from each other and having a volume variable in relation to the movements of said rod (1), said second chamber (52) being connected to said reservoir (11) by at least one first further conduit (53A, 53B) and to the outside by a second further conduit (54) comprising a closure plug (55).
- An apparatus as claimed in claim 1, characterised in that the intermediate chamber (23) is connected to the reservoir (11) by a tube (60) dipping into said reservoir in correspondence with a central region thereof.
- An apparatus as claimed in claim 1, characterised in that the return conduit (56) of the first chamber and that (53A) of the second chamber (52) have a common portion.
- An apparatus as claimed in claim 1, characterised in that the deformable wall (12) is cup-shaped.
- An apparatus as claimed in claim 4, characterised by comprising a reservoir closure cover (13) arranged to fix and seal the deformable wall (12) to the lateral wall of the reservoir, said cover being cup-shaped.
- An apparatus as claimed in claim 1, characterised in that the cylinder (2) is sealed at both its ends by two different elements (8, 50), one of said elements having a through hole through which the die-carrying rod (1) can sealedly slide.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT1995MI000811U IT237303Y1 (en) | 1995-11-23 | 1995-11-23 | HYDRAULIC TRANSMISSION PIPE BENDING MACHINE |
ITMI950811U | 1995-11-23 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0775538A1 EP0775538A1 (en) | 1997-05-28 |
EP0775538B1 true EP0775538B1 (en) | 1998-08-12 |
Family
ID=11371405
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP96117812A Expired - Lifetime EP0775538B1 (en) | 1995-11-23 | 1996-11-07 | Pipe bending apparatus with hydraulic transmission |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0775538B1 (en) |
AT (1) | ATE169529T1 (en) |
DE (1) | DE69600518T2 (en) |
ES (1) | ES2120795T3 (en) |
IT (1) | IT237303Y1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT1295321B1 (en) * | 1997-10-13 | 1999-05-04 | Cbc Spa | HYDRAULIC TRANSMISSION PIPE CHOKE DEVICE |
DE29906511U1 (en) * | 1998-05-19 | 1999-08-12 | Geberit Technik AG, Jona, St.Gallen | Bending device with hydraulic drive |
IT201800010409A1 (en) * | 2018-11-16 | 2020-05-16 | Cml Int S P A | Machine for bending an elongated piece without creasing |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT207711Z2 (en) * | 1985-10-31 | 1988-02-08 | C B C Spa | HYDRAULIC TRANSMISSION PIPE BENDING UNIT OPERATED WITH ONE HAND |
-
1995
- 1995-11-23 IT IT1995MI000811U patent/IT237303Y1/en active IP Right Grant
-
1996
- 1996-11-07 ES ES96117812T patent/ES2120795T3/en not_active Expired - Lifetime
- 1996-11-07 DE DE69600518T patent/DE69600518T2/en not_active Expired - Lifetime
- 1996-11-07 EP EP96117812A patent/EP0775538B1/en not_active Expired - Lifetime
- 1996-11-07 AT AT96117812T patent/ATE169529T1/en active
Also Published As
Publication number | Publication date |
---|---|
ATE169529T1 (en) | 1998-08-15 |
ES2120795T3 (en) | 1998-11-01 |
EP0775538A1 (en) | 1997-05-28 |
DE69600518D1 (en) | 1998-09-17 |
ITMI950811V0 (en) | 1995-11-23 |
DE69600518T2 (en) | 1999-01-07 |
ITMI950811U1 (en) | 1997-05-23 |
IT237303Y1 (en) | 2000-09-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4597263A (en) | Pull type installation tool | |
EP0355780B1 (en) | Method for filling a hydro-pneumatic pressure amplifier with oil, and apparatus therefor | |
US4206603A (en) | Single hand operated tool | |
DE4121316A1 (en) | Washer jet for headlamp of motor vehicle - has extending mounting with integral non-return valve | |
EP0117243B1 (en) | Pneumatic hydraulic hand-held power unit | |
US4118969A (en) | Double action fastener installation tool for blind rivets and the like | |
EP0775538B1 (en) | Pipe bending apparatus with hydraulic transmission | |
US5265710A (en) | Hydraulic self-adjusting device for clutch control cables | |
DE2601836A1 (en) | VALVE ARRANGEMENT FOR A PNEUMATIC NAILER | |
US5445002A (en) | Fill and pressurization apparatus | |
DE2230418C3 (en) | Brake booster | |
DE69510418T2 (en) | HYDRAULIC ACTUATING SYSTEMS | |
US4543790A (en) | Master cylinder and brake booster assembly | |
DE2460529A1 (en) | MASTER CYLINDER FOR HYDRAULIC BRAKE SYSTEM | |
DE69105085T2 (en) | Rivet setting tool. | |
US4236549A (en) | Bleeder kit for bleeding a master cylinder | |
DE2944053C2 (en) | ||
KR950010069B1 (en) | A booster for a press machine | |
US4149381A (en) | Single hand operated tool | |
DE19717486A1 (en) | Pneumatic pressure amplifier for hydraulic installation | |
US20020112353A1 (en) | Hydraulic punch driver | |
DE60222209T2 (en) | Pneumatic control valve for brake control of a towed vehicle | |
DE523563C (en) | Braking device for motor vehicles | |
US5207061A (en) | Master cylinder with externally adjusted secondary compensation | |
DE2738177A1 (en) | FLUID OPERATED HYDRAULIC PUMP |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT CH DE ES FR GB IT LI |
|
17P | Request for examination filed |
Effective date: 19970513 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
17Q | First examination report despatched |
Effective date: 19971211 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT CH DE ES FR GB IT LI |
|
REF | Corresponds to: |
Ref document number: 169529 Country of ref document: AT Date of ref document: 19980815 Kind code of ref document: T |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: NV Representative=s name: R. A. EGLI & CO. PATENTANWAELTE |
|
REF | Corresponds to: |
Ref document number: 69600518 Country of ref document: DE Date of ref document: 19980917 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2120795 Country of ref document: ES Kind code of ref document: T3 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20150921 Year of fee payment: 20 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 20 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 20151127 Year of fee payment: 20 Ref country code: IT Payment date: 20151026 Year of fee payment: 20 Ref country code: DE Payment date: 20151103 Year of fee payment: 20 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 20151021 Year of fee payment: 20 Ref country code: FR Payment date: 20151117 Year of fee payment: 20 Ref country code: ES Payment date: 20151126 Year of fee payment: 20 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R071 Ref document number: 69600518 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: PE20 Expiry date: 20161106 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK07 Ref document number: 169529 Country of ref document: AT Kind code of ref document: T Effective date: 20161107 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20161106 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 20170224 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20161108 |