CA2705646A1 - Device and method for preventing a tool from breaking during fine blanking and/or forming a work piece - Google Patents

Device and method for preventing a tool from breaking during fine blanking and/or forming a work piece Download PDF

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Publication number
CA2705646A1
CA2705646A1 CA 2705646 CA2705646A CA2705646A1 CA 2705646 A1 CA2705646 A1 CA 2705646A1 CA 2705646 CA2705646 CA 2705646 CA 2705646 A CA2705646 A CA 2705646A CA 2705646 A1 CA2705646 A1 CA 2705646A1
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Canada
Prior art keywords
pressure
piston
shaped projection
touch
preloading
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Granted
Application number
CA 2705646
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French (fr)
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CA2705646C (en
Inventor
Markus Schaltegger
Alfio Cristofaro
Juerg Ochsenbein
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Feintool International Holding AG
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Feintool Intellectual Property AG
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Publication of CA2705646A1 publication Critical patent/CA2705646A1/en
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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B30PRESSES
    • B30BPRESSES IN GENERAL
    • B30B15/00Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/28Arrangements for preventing distortion of, or damage to, presses or parts thereof
    • B30B15/285Arrangements for preventing distortion of, or damage to, presses or parts thereof preventing a full press stroke if there is an obstruction in the working area
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23QDETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q17/00Arrangements for observing, indicating or measuring on machine tools
    • B23Q17/09Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool
    • B23Q17/0904Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool before or after machining
    • 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
    • B21D24/00Special deep-drawing arrangements in, or in connection with, presses
    • B21D24/10Devices controlling or operating blank holders independently, or in conjunction with dies
    • B21D24/14Devices controlling or operating blank holders independently, or in conjunction with dies pneumatically or hydraulically
    • 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
    • B21D28/00Shaping by press-cutting; Perforating
    • B21D28/24Perforating, i.e. punching holes
    • 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
    • B21D55/00Safety devices protecting the machine or the operator, specially adapted for apparatus or machines dealt with in this subclass
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23QDETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q17/00Arrangements for observing, indicating or measuring on machine tools
    • B23Q17/09Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B30PRESSES
    • B30BPRESSES IN GENERAL
    • B30B15/00Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16Control arrangements for fluid-driven presses
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00Cutting
    • Y10T83/869Means to drive or to guide tool
    • Y10T83/8696Means to change datum plane of tool or tool presser stroke

Abstract

The invention relates to a device and a method for preventing a tool consisting of an upper and an lower part from breaking during fine blanking and/or forming in a press.
The invention has the task to provide a solution for preventing a tool from breaking during fine blanking and/or forming a work piece, which is able to simplify the construction and to reduce the quantity of parts simultaneously reducing the costs, to absorb high tilting moments and to compensate the kinetic energy of the drive during a return stroke even before the press is switched off.
This task is solved by providing between V-shaped projection piston (9) and V-shaped projection pins (11) a touch piston (10), that with the V-shaped projection piston (9) on the one hand and with the V-shaped projection pins (11) and the V-shaped projection pressure plate (12) on the other hand develops an axially to each other movable arrangement, wherein the V-shaped projection piston (9) is allocated a pressure room (16) to which a preloading pressure (P1) of the hydraulic system can be admitted, between V-shaped projection piston (9) and touch piston (10) is allocated a pressure room (24) to which a touch piston pressure (P2) can be admitted and the touch piston (10) is allocated a further pressure room (31) to which can be admitted a differential pressure (P3), wherein the pressure rooms (16, 24, 31) each via one connection (17, 25, 32) in the V-shaped projection cover (15) and the pressure rooms (24, 31) respectively via separate positioned in the main cylinder (3) conduits (23, 29) are connected with the hydraulic system for admitting pressure to the V-shaped projection piston (9) and the touch piston (10) opposite to the effective direction of the preloading pressure (P1), and to provide a touch table (7) suspendedly hold against an applied to the main plate (6) fixing means (46) in a determined detection distance (TA) weight compensated by the main plate (6), to which detection distance (TA) is allocated a sensor (52) that in case of a change of the detection distance (TA) transmits a signal to the computer (57) to immediately stop the press to protect the upper part of the tool (50).

Description

--------------------------------------------------------------Device and method for preventing a tool from breaking during fine blanking and/or forming a work piece --------------------------------------------------------------Description [0001] The invention relates to a device for preventing a tool consisting of an upper and an lower part from breaking during fine blanking and/or forming in a press with a positioned above a ram carrying out a stroke movement fine blanking head, which comprises a main cylinder accommodating a V-shaped projection piston lying on the stroke axis and several with regard to the stroke axis coaxially arranged V-shaped projection pins, which are axially guided in a main plate covering the main cylinder and supported on a V-shaped projection pressure plate, wherein the main cylinder is hold in the head piece of the press and closed by a V-shaped projection cover and wherein the fine blanking head is connected with a hydraulic system for producing pressure acting on the tool parts via valves, which are triggered by a computer.
[0002] The invention further relates to a method for preventing a tool consisting of an upper and an lower part from breaking during fine blanking and/or forming in a press, wherein the guided in the main cylinder of the fine blanking head V-shaped projection and touch pistons for producing a V-shaped projection force and a stripping force are admitted to an adjustable pressure from a hydraulic system, wherein the single pressure values for the pistons are adjusted by valves triggered by a computer.
State of the art [0003] From the DE 24 19 390 C2 is known a device for the protection of a tool set of a hydraulic fine blanking press, the ram of which can be lifted by quick-elevating piston units and a working stroke pressure unit, wherein between the ram-driving element and a driven ram part exists a detectable gap, that can be maintained in case of the approach of a pressure means with low force and closes in case of higher pressure loads on the parts developing it, the state of which can be monitored by a sensor and a way switch until the ram has neared the tools to start the regular working stroke. The detectable gap is developed between the ram and the frontal surfaces of the piston rods of the quick-elevating pistons and pressure is admitted to the detectable gap by touch cylinders in the ram, when the touch pistons of them respectively rest against a part of the mentioned before frontal surfaces.
In this known protection device the detectable gap before the quick-elevating piston unit is allocated to the ram and positioned upstream to it. This protection device is always then actuated, when the detectable gap closes due to an elevated pressure load.
It has the disadvantage that punchings, parts or foreign bodies in the tool are not detected and thus damages at the tool can not be prevented.

[00024] Another known solution (DE 69 17 177 U) for a tool protection in presses for processing a blank discloses between a first tool moved by the working piston and a fixed to the frame tool two switches, which have to be actuated in a predetermined sequence, for interrupting the working stroke in case of an inverse actuating sequence. For attaching the first tool is provided an axially movable with regard to the working piston element, which during the working stroke is hold at a small distance before the working piston by elastic flexible means. A first adjustable to the nominal height of the blank to be processed limit stop switch is actuated by a limit stop, when the piston has moved a part of its working stroke predetermined by the adjustment of the first limit stop switch. A further limit stop switch is actuated by a further limit stop, when the element by the blank or a foreign body hitting the second tool is pushed back by the small distance onto the piston.
The element is realized as a lower tool mounting surface supporting on a cylinder together with the working piston enclosing a ring-shaped pressure chamber, which is connected to a pressure fluid pipe having a shutting element, that makes it possible to let as much compressed air into the ring chamber to hold the mounting surface during the working stroke practically floating before the piston.
This known solution has the disadvantage, that besides the hydraulic system a second separate system is necessary, that works with compressed air and thus causes a considerable effort regarding circuitry and construction. Besides that, after the detection of a foreign body there is no possibility to compensate the kinetic energy of the drive.

[0005] Other known solutions for detecting punchings or other foreign bodies in the tool use optical sensors or ultrasonic sensors.
Task [0006] At this state of the art the invention has the task to provide a solution for preventing a tool from breaking during fine blanking and/or forming, which is able to simplify the construction and to reduce the quantity of parts simultaneously reducing the costs, to absorb high tilting moments and to compensate the kinetic energy of the drive during a return stroke even before the press is switched off.
[0007] This task is solved by a device of the above mentioned kind with the characterizing elements of claim 1 and by a method with the characterizing elements of claim 14.

[00028] Advantageous aspects of the device and the method according to the invention can be learned from the subclaims.
[0009] The solution according to the invention proceeds from the finding to integrate the function of detecting punchings, parts or other foreign bodies into the active elements of the fine blanking head, that is to provide a touch piston between V-shaped projection piston and V-shaped projection pins, that with the V-shaped projection piston on the one hand and with the V-shaped projection pins and the V-shaped projection pressure plate on the other hand develops an axially to each other movable arrangement, wherein the V-shaped projection piston is allocated a pressure room to which a preloading pressure of the hydraulic system can be admitted, between V-shaped projection piston and touch piston is allocated a pressure room to which a touch piston pressure can be admitted and the touch piston is allocated a further pressure room to which can be admitted a differential pressure, wherein the pressure rooms each via one connection in the V-shaped projection cover and the pressure rooms respectively via separate positioned in the main cylinder conduits are connected with the hydraulic system for admitting pressure to the V-shaped projection piston and the touch piston opposite to the effective direction of the preloading pressure, and to provide a touch table suspendedly hold against an applied to 5 the main plate fixing means in a determined detection distance weight compensated by the main plate, to which is allocated a sensor that in case of a change of the detection distance transmits a signal to the computer to immediately stop the press to protect the upper part of the tool.
[0010] Of special importance is that the touch table, the main plate, the central support, the main cylinder and the adjusting nut non-positively and/or positively divert the pressing force into the head piece of the press depending on the motion of V-shaped projection piston, V-shaped projection pins and touch piston between upper and lower dead points.
[0011] According to an especially advantageous aspect of the device according to the invention the second pressure room allocated to the V-shaped projection piston is developed below a projecting in the direction of the stroke axis supporting shoulder at the wall of the main cylinder in the direction of the lower piston surface of the V-shaped projection piston.
At the same time the touch piston is allocated a pressure room developed below a provided at the touch piston shoulder and above a projecting in the direction of the stroke axis supporting shoulder at the wall of the main cylinder.

This design in a simple manner guarantees that in the opposite direction to the preloading pressure P1 applied to the V-shaped projection piston a touch piston pressure P2 can act on the V-shaped projection piston and a differential pressure P3 on the touch piston, what causes an axial shift of V-shaped projection piston, touch piston and V-shaped projection pins.
[0012] Further it is of advantage that the pressure room of the V-shaped projection piston via a connection in the V-shaped projection cover is connected to a pressure pipe of the hydraulic system, that via a proportional valve applies to the pressure room a preloading pressure for producing the V-shaped projection force or a stripping pressure for producing a stripping force or makes it motionless.

[0013] Moreover, it is preferred that the second pressure room of the V-shaped projection piston and at the same time the pressure room for the touch piston via a connection at the V-shaped projection cover and a directional control valve to connect the pressure in the second pressure room by a feeding pipe are connected with the pressure pipe of the hydraulic system.

[0014] According to a further aspect of the device according to the invention the conduits leading into the pressure rooms are axially arranged in the direction to the stroke axis in the wall of the main cylinder and open respectively bending into the respective pressure rooms.

[0015] Furthermore, for feeding different quantities of hydraulic fluid into the single pressure rooms it is provided, that the conduit for the V-shaped projection piston with regard to the conduit for the touch piston has a bigger diameter.

[0016] In an especially advantageous aspect of the device according to the invention the fixing means comprises a pressure spring and a straining screw, which are positioned in a recess of the main plate, wherein the straining screw penetrates the main plate and the pressure spring serves for compensating the weight of the touch table and the upper part of the tool.
[0017] A further advantageous aspect of the device according to the invention provides, that the sensor is adjustably positioned in a seat of the main plate, the measuring point of which is determined by an arranged in the touch table switch flag, what guarantees an exact adjustment of the detection distance to the gap distance.
The gap distance in case of an immediate stop of the press serves to advantageously compensate the kinetic energy even before the press has stopped.
[00181 Furthermore, it is preferred to provide, that the main plate is attached at a frontal side of the main cylinder facing the ram with screwing means.

[0019] In a further preferred aspect of the device according to the invention the touch table is torsion-proof and axially movable arranged to the main plate by axially parallel to the stroke axis guided in holes guiding pins.

[0020] An especially advantageous aspect of the device according to the invention consists in, that the V-shaped projection pins and the V-shaped projection pressure plate are positioned coaxially with regard to the stroke axis, wherein the pressure plate is fixed at the touch table by a retaining ring and a central support is integrated in the main plate.

[00211 Furthermore, the task of the invention is solved by the method that way, that the pressure force is diverted by means of a non-positive and/or positive connection by hydraulic locking and unlocking of a touch table, a main plate, a central support, a main cylinder and an adjusting nut into the head piece of the press and by axially shifting of V-shaped projection piston and touch piston in alignment with the stroke axis (HU) prior to feeding in the pressure force until the non-positive and/or positive connection between V-shaped projection pressure plate, V-shaped projection pins, touch piston and V-shaped projection piston is reached, wherein between touch piston and V-shaped projection pins with hydraulic means is adjusted a gap distance and between main plate and touch table with mechanical means is adjusted an adjusted to the gap distance weight compensated detection distance, the change of which is scanned by the V-shaped pressure plate and/or the touch table in case of an inverse sequence of the stroke and detected by a sensor transmitting a signal to the computer, what causes the immediate stop of the press.
The kinetic energy is compensated in the gap distance between touch table and V-shaped projection pins because the touch table can move in the direction of the V-shaped projection pins.

[0022] The method according to the invention is realized especially in the following preferred steps:

a Preloading of V-shaped projection piston and touch piston to a preloading pressure P1 to realize the non-positive connection between them b Permanently applying a different from the preloading pressure P1 differential pressure P3 to the touch piston for axially shifting the touch piston, c Maintaining a detection distance TA adjusted to a gap distance between touch piston and V-shaped projection pins by the applied to the touch piston differential pressure P3 and the acting against it preloading pressure P1 for realizing a non-positive connection between touch piston and V-shaped projection piston, wherein the preloading pressure P1, the touch piston pressure P2 and the differential pressure P3 are adjusted to the condition P1 >> P3 and P2 = 0, d Superseding the hydraulic fluid being under differential pressure P3 in the allocated to the touch piston pressure room by the applied to the upper pressure room preloading pressure P1, e Relieving the V-shaped projection piston by switching off the preloading pressure P1 in the upper dead point for reaching a motionless state of V-shaped projection piston and touch piston, f Stripping of V-shaped projection piston and touch piston by applying a stripping pressure P4 and a touch piston pressure P2 with a constant value to the pressure rooms of V-shaped projection piston and touch piston, g Shifting the V-shaped projection piston and the touch piston until a sensor triggers a signal, h Switching off the stripping pressure P4 for the V-shaped projection piston and the touch piston and applying the preloading pressure P1 to the upper pressure room of the V-shaped projection piston, i Repeating the step sequence a) to h) in case the sensor has not detected a depending on the ram stroke premature change of the detection distance TA.
[0023] A further preferred aspect of the method according to this invention provides, that the preloading pressure for the V-shaped projection piston is adjusted to a high pressure of more than 110 bar.

[0024] The method according to the invention further provides in a preferred aspect, that the touch piston pressure P2 and the stripping pressure P4 are adjusted to a low pressure below 110 bar, - the differential pressure P3 is adjusted to a low pressure below 110 bar or to zero.

[0025] Further advantages and details of the invention 10 accrue from the following description with reference to the attached drawings.

Embodiment [0026] In the following the invention will be explained in more detail on the example of one embodiment.

It is shown in:

[0027] Fig. 1 a perspective view of the press with the device according to the invention assembled in the head piece, [0028] Fig.2 a cross-section of the device according to the invention in the extended state, [0029] Fig.3. a cross-section of the device according to the invention in the retracted state, [0030] Fig. 4 a cross-section of the main plate and the touch table with illustration of the mechanical weight compensation and [0031] Fig. 5 a cut out cross-section of the main plate and the touch table illustrating the arrangement of the sensor and the position of gap distance and detection distance.
[0032] Fig. 1 shows a perspective view of a mechanically driven toggle-type fine blanking press. The supporting a table top ram 1 of this press carries out a lifting movement in the direction of the stroke axis HU and in the direction of the head piece 2 of the press. In the head piece 2 of the press is positioned the device according to the invention in alignment with the stroke axis HU.

[0033] Fig. 2 shows a cross-section of the device according to the invention. The device according to the invention as compact construction unit is assembled into the head piece 2 of the press and form-fit fixed there. The device according to the invention comprises a fine blanking head FSK, which essentially consists of a main cylinder 3, an adjusting nut 4, a fixed to the head piece 2 flange 5, a main plate 6 and a touch table 7. Main cylinder 3, adjusting nut 4, flange 5, main plate 6 and touch table 7 together develop a non-positive arrangement diverting the whole pressure force into the head piece 2 of the press. The non-positive connection is achieved by locking the motion threads BW1 and BW2 at the head of the main cylinder 3 and at the adjusting nut 4 by pressing the motion thread BW1 of the main cylinder 3 against the motion thread BW2 of the adjusting nut 4 into the direction of the upper dead point OT by means of a hydraulic pressure PV. The unlocking of the two motion threads BW1 and BW2 is carried out by switching off the hydraulic pressure PV.
The non-positive connection is illustrated by the gray colored area in Fig. 2.

The head piece 2 is connected to the frame 8 of the press by straining screws SB (see Fig. 1).

[0034] In the main cylinder 3 are accommodated a V-shaped projection piston 9 and a touch piston 10 in axial alignment to each other. The V-shaped projection pins 11 penetrate the main plate 6 and support on a V-shaped projection pressure plate 12, which is secured by a V-shaped projection retaining ring 13 fixed to the touch table 7.
The main cylinder 3 is pressure-tight closed at its head side by a V-shaped projection cover 15 and above the V-shaped projection piston 9 develops a pressure room 16, which via a connection 17 and an adjustable valve 18 by a feeding pipe 19 is connected to the pressure pipe 56 of the hydraulic system for producing a hydraulic preloading pressure P1 acting on the V-shaped projection piston 9 in the direction of the lower dead point UT.

[0035] The main cylinder 3 - as Fig. 3 shows - at is internal wall 20 has a first step-like projecting in the direction of the stroke axis HU shoulder 21 for supporting and limiting the stroke into the direction of the lower dead point UT of the V-shaped projection piston 9. Below this first shoulder 21 is positioned a second projecting in the direction of the stroke axis HU shoulder 22 bordering the pressure room 31 of the touch piston 10.
In the wall 20 of the main cylinder 3 is accommodated an axially extending conduit 23, which bending around about 45 in the direction of the stroke axis HU below the first shoulder 21 opens through the internal wall 20. Below the V-shaped projection piston 9 develops a pressure room 24 into which is fed the hydraulic fluid under a touch piston pressure P2.
The conduit 23 to this is connected with a connection 25 at the V-shaped projection cover 15, which is connected via a controllable valve 26 and a respective feeding pipe 27, which on its part is connected to the low-pressure pipe 56a of the hydraulic system.

Furthermore, in the wall 20 of the main cylinder 3 is provided an axially extending conduit 29, which bending around about 45 in the direction of the stroke axis HU opens from the internal wall 20 below the second developed at the internal wall 20 shoulder 22 and develops a pressure room 31 below a shoulder 30 of the touch piston 10. The conduit 29 at the V-shaped projection cover 15 is connected with a connection 32, which is connected via a controllable valve 33, via a feeding pipe 34 and reservoir 28 to the hydraulic system. To the pressure room 31 in the direction of the upper dead point OT is admitted hydraulic fluid under a differential pressure P3, so that the touch piston 9 tries to move in the direction of the upper dead point OT.
The pressures P2 and P3 act against the preloading pressure P1, wherein the pressure P3 causes the touch piston 10 to non-positively connect to the lower side 35 of the V-shaped projection piston 9.

[0036] Between the lower side 36 of the touch piston 10 and the frontal surface 37 of the V-shaped projection pins 11 is provided a determined gap distance SP, that can amount to for example 4 to 10 mm, preferably is 6 mm.
The gap distance SP forms a sufficiently long stopping distance needed in case of a immediate stop of the press to brake the kinetic energy or to retard it.

The V-shaped projection pins 11 non-positively and/or positively support on the V-shaped projection pressure plate 12, so that a hydraulic displacement can be realized in dependence on the touch stroke and the pressure P3 against the pressure P1. The total V-shaped projection force produced by the preloading pressure than is reduced by the force produced by the differential pressure P3.

[0037] The head piece 2 at its facing the stroke axis HU
internal wall 42 has a projecting in the direction of the stroke axis HU step-like upper shoulder 43, on which supports the adjusting nut 4 and is axially secured in the direction to the upper dead point OT. The adjusting nut 4 is axially hold in the direction to the lower dead point UT by the tube-like part 39 of the flange 5.
[0038] In the flange 5 are provide two positioned diametrically opposite holes 38, which are positioned in the tube-like part 39 parallel to the stroke axis HU.
These holes 38 serve for accommodating pin-like guiding pins 40 axially guiding the main plate 6 and serving as antitwist protection for the main plate 6 and the main cylinder 3.
[0039] As Fig. 4 shows in the main plate 6 is located a recess 45 for accommodating a fixing means 46 consisting of a pressure spring 47 and an adjusting screw 48. The fixing means 46 makes it possible to hold the touch table 7 and the upper part of the tool 50 compensated according to weight. In other words, the weights of the touch table 7 and the upper part of the tool 50 are compensated. At the lower side 49 of the touch table 7 are located standard fixing means for fixing the upper tool part 50, so that it is not necessary to describe them in detail.

[0040] Fig. 5 shows a cut out cross-section of the main plate 6 and the touch table 7. In the main plate 6 vertically to the stroke axis HU is provided a recess 51 in which is positioned a sensor 52 for detecting the detection distance TA. The measuring point MP of the sensor 52 ends in an arranged parallel to the stroke axis HU accessible from the lower side 53 of the main plate 6 recess 54 for the measuring point MP of the sensor 52.
Via the sensor 52 the distance to be detected TA is exactly adjusted.

[0041] Fig. 5 also illustrates the position of the gap distance SP between the lower side of the touch piston 10 and the frontal surface of the V-shaped projection pins 11 on the one hand and of the detection distance between the lower side 53 of the main plate 6 and the upper side of the touch table 7 on the other hand.

[0042] The hydraulic system - as shown in Fig 3 - consists of a pressure pipe 56, which by a not shown pressure source is loaded to a pressure of 250 bar. To this pressure pipe 56 is connected the feeding pipe 19 extending via the controllable 5 proportional valve 18 to the positioned above the V-shaped projection piston 9 pressure room 16. Via the proportional valve 18 is fed the hydraulic preloading pressure Pi acting in the direction to the lower dead point UT on the V-shaped projection piston 9 for producing the V-shaped projection 10 force. The preloading pressure P1 can be adjusted to a pressure between 20 and 250 bar.
From a low-pressure pipe 56a a feeding pipe 27 via the controllable directional control valve 26 extends into the pressure room 24 producing the stripping pressure P4 for the 15 touch piston 10. The touch piston pressure P2 is directly provided from the hydraulic system.

A further feeding pipe 34 extends from the low-pressure pipe 56a via a reservoir 28 into the pressure room 31 below the touch piston 10. The differential pressure P3 acts against the preloading pressure P1 and makes it possible to not-positively connect touch piston 10 and V-shaped projection piston 9, to hold them connected but also to disconnect the non-positive connection again by switching on the valve 33. In addition this way the pressure potential of the reservoir 28 can be emptied.

[0043] In the following the method according to the invention is described in more detail.
The preloading pressure P1 developing the V-shaped projection force is diverted by the non-positive and/or positive connection of touch piston 10, V-shaped protection piston 9 and V-shaped projection pins 11. Before the preloading pressure P1 is admitted until the non-positive connection of V-shaped projection piston 9 and touch piston 10 is reached the latter are moving in alignment with the stroke axis HU
because of the applied differential pressure P3. This results in a non-positive connection between the lower side of the touch piston 10 and the frontal surface of the V-shaped projection piston 9. Between the touch piston 10 and the V-shaped projection pins 11 is realized a fix gap distance SP, which for instance is 6 mm.
The touch table 7 is weight compensated suspendedly positioned at the main plate 6, wherein for its axial movement are provided four guiding pins 40 and for the weight compensation four mechanical fixing means 46.
A sensor 52 allocated to the detection distance TA detects a dependent on the ram stroke too early change of the detection distance TA and produces a signal fed into a computer 57 for processing the signals.
It is differentiated between two signal conditions. The proper form-fit connection between V-shaped projection pressure plate 12, V-shaped projection pin 11, touch piston 10 and V-shaped projection piston 9 causes a displacement against the preloading pressure P1, that is it is carried out a standard cancellation of the detection stroke, that is the touch table 7 and the V-shaped projection pressure plate 12 touch the main plate 6 without a change of the detection distance TA could be detected. The single process steps of the method according to the invention are carried out continuously.

In case the detection distance TA is changed for example by punchings or other foreign bodies the sensor 52 detects this change and transmits this information to the computer 57, where it is further processed. The change of the detection distance leads to a too early cancellation of the detection stroke, so that the computer 57 causes an immediate stop of the press. The kinetic energy during an immediate stop due to the sufficient high detection distance is braked or retarded by the drive.
[0044] In the process step a) the V-shaped projection piston 9 and the touch pistonl0 are preloaded to a high pressure P1.
[0045] The detection distance TA adjusted to the gap distance SP of touch piston 10 and V-shaped projection pins 11 in step b) is kept by the resulting differential pressure P3, whereby a non-positive connection between touch piston 10 and V-shaped projection piston 9 is realized.
The differential pressure P3 for example was adjusted to 65 bar.

[0046] The process step c) provides, that the being under differential pressure P3 touch piston 10, V-shaped projection pins 11, V-shaped projection pressure plate 12 and the being under preloading pressure P1 V-shaped projection piston 9 are displaced by the ram 1.' [0047] The V-shaped projection piston 9 then by switching off the preloading pressure P1 in the upper dead point OT is relieved in step d).

[0048] According to process step e) to the touch piston 10 is applied a differential pressure P3 of for example 65 bar, which makes it possible to realize or cancel the non-positive connection between touch piston 10 and V-shaped projection piston 9 due to an axial movement of the touch piston 10.
[0049] In step f) the V-shaped projection piston 9 and the touch piston 10 are stripped and a desired stripping pressure P4 of for example 70 bar is adjusted with the valve 18 in the belonging to the V-shaped projection piston 9 pressure room 16 with the differential pressure P3 being applied.
Simultaneously with the stripping pressure P4 is applied the touch piston pressure P2 of for example 65 bar.
[0050] The stripping pressure P4 then in step g) is switched off and the pressure P1 is applied to the upper pressure room 16 of the V-shaped projection piston 9, when via touch piston 10, V-shaped projection pins 11 and V-shaped projection pressure plate 12 was transmitted the signal for reaching the gap distance SP from the sensor 52.

[0051] The sequence of the steps a) to g) then is repeated.
[0052] When this closing movement is actuated by a too early change of the detection distance TA, is carried out a quick stop, that is an immediate stop of the press. A too early closing movement is always then actuated, when punchings, parts or other foreign parts are in the upper tool, because this leads to a too early change of the detection distance TA.
[0053] List of reference signs ram 1 head of the press 2 main cylinder 3 adjusting nut 4 flange 5 main plate 6 touch table 7 frame of the press 8 V-shaped projection piston 9 touch piston 10 V-shaped projection pins 11 V-shaped projection pressure plate 12 V-shaped projection retaining ring 13 central support 14 V-shaped projection cover 15 upper pressure room for 9 16 connection in 15 17 proportional valve 18 feeding pipe for 16 19 internal wall of 3 20 first projecting shoulder 21 second projecting shoulder 22 conduit for 24 23 lower pressure room of 9 24 connection for 24 in 15 25 controllable valve in 27 26 feeding pipe for 24 27 reservoir for 24 28 conduit 29 shoulder in touch piston 10 30 pressure room for touch piston 10 31 connection for 31 32 controllable valve for 34 33 feeding pipe for 31 34 lower side of the V-shaped projection piston 9 35 lower side of touch piston 10 36 frontal surface of V-shaped projection piston 9 37 holes 38 tube-like part of 5 39 guiding pins 40 frontal surface of 40 41 internal wall of 2 42 shoulder at 2 43 screwed connection 44 recess in main plate 6 45 fixing means 46 pressure spring 47 adjusting screw 48 lower side of touch table 49 upper part of tool 50 recess 51 sensor 52 lower side of the main plate 53 axial recess in 6 54 limit stops 55 high-pressure pipe of the hydraulic system 56 5 low-pressure pipe of the hydraulic system 56a computer 57 motion thread at main cylinder 3 BW1 motion thread at adjusting nut 4 BW2 fine blanking head FSK

10 stroke axis of 1 HU
measuring point of 52 MP
upper dead point OT
preloading pressure P1 touch piston pressure P2 15 differential pressure P3 stripping pressure P4 locking and unlocking pressure PV
gap distance SP
detection distance TA
20 lower dead point UT
To this belong 5 sheets with drawings

Claims (18)

1. Device for preventing a tool consisting of an upper and an lower part from breaking during fine blanking and/or forming in a press with a positioned above a ram (1) carrying out a stroke movement fine blanking head (FSK), which comprises a main cylinder (3) accommodating a V-shaped projection piston (9) lying on the stroke axis (HU) and several with regard to the stroke axis (HU) coaxially arranged V-shaped projection pins (11), which are axially guided in a main plate (6) covering the main cylinder(3) and supported on a V-shaped projection pressure plate (12), wherein the main cylinder (3) is hold in the head piece (2) of the press and pressure-tight closed by a V-shaped projection cover (15) and wherein the fine blanking head (FSK) is connected with a hydraulic system for producing pressure acting on the tool via valves (18, 26, 33), which are triggered by a computer (57), characterized in that between V-shaped projection piston (9) and V-shaped projection pins (11) is provided a touch piston (10), that with the V-shaped projection piston (9) on the one hand and with the V-shaped projection pins (11) and the V-shaped projection pressure plate (12) on the other hand develops an axially to each other movable arrangement, wherein the V-shaped projection piston (9) is allocated a pressure room (16) to which a preloading pressure (P1) of the hydraulic system can be admitted, between V-shaped projection piston (9) and touch piston (10) is allocated a pressure room (24) to which a touch piston pressure (P2) can be admitted and the touch piston (10) is allocated a further pressure room (31) to which can be admitted a differential pressure (P3), wherein the pressure rooms (16, 24, 31) each via one connection (17, 25, 32) in the V-shaped projection cover (15) and the pressure rooms (24, 31) respectively via separate positioned in the main cylinder (3) conduits (23, 29) are connected with the hydraulic system for admitting pressure to the V-shaped projection piston (9) and the touch piston (10) opposite to the effective direction of the preloading pressure (P1), and to provide a touch table (7) suspendedly hold against an applied to the main plate (6) fixing means (46) in a determined detection distance (TA) weight compensated by the main plate (6), to which detection distance (TA) is allocated a sensor (52) that in case of a change of the detection distance (TA) transmits a signal to the computer (57) to immediately stop the press to protect the upper part of the tool (50).
2. Device according to claim 1, characterized in that the pressure room (24) allocated to the V-shaped projection piston (9) is developed below a projecting in the direction of the stroke axis (HU) supporting shoulder (21) at the wall (20) of the main cylinder (3) in the direction of the lower piston surface (35) of the V-shaped projection piston (9).
3. Device according to claim 1, characterized in that the allocated to the touch piston (10) pressure room (31) is developed below a provided at the touch piston (10) shoulder (30) and above a projecting in the direction of the stroke axis (HU) supporting shoulder (22) at the wall (20) of the main cylinder (3).
4. Device according to claims 1 to 3, characterized in that the pressure room (16) for the V-shaped projection piston (9) via the connection (17) at the V-shaped projection cover (15) is connected to a feeding pipe (19) of a high-pressure pipe (56) of the hydraulic system, wherein via a proportional valve (18) positioned in the feeding line (19) to the pressure room (16) can be applied a preloading pressure (P1) for producing the V-shaped projection force or a pressure for producing a stripping pressure (P4) or it can be made motionless.
5. Device according to claims 1 to 3, characterized in that the pressure room (24) for the V-shaped projection piston (9) and the touch piston (10) via the connection (25) at the V-shaped projection cover (15) and a directional control valve (26) for admitting the touch piston pressure (P2) to the pressure room (24) is connected by a feeding pipe (27) with a low-pressure pipe (56a) of the hydraulic system.
6. Device according to claims 1 to 3, characterized in that the pressure room (31) for the touch piston (10) via the connection (32) at the V-shaped projection cover (15) and a directional control valve (33) for admitting the differential pressure (P3) to the pressure room (31) is connected by a feeding pipe (34) with the low-pressure pipe (56a) of the hydraulic system.
7. Device according to claims 1 to 3, characterized in that the leading to the pressure rooms (24, 31) conduits (23, 29) in the wall (20) of the main cylinder (3) are coaxially arranged in the direction to the stroke axis (HU) and open respectively bending into the pressure rooms (24, 31), so that to the V-shaped projection piston (9) and the touch piston (10) can be applied pressure against the effective direction of the preloading pressure (P1).
8. Device according to claims 1 to 3 and 5, characterized in that the conduit (23) for the V-shaped projection piston (9) and touch piston (10) with regard to the conduit (29) for the differential pressure (P3) at the lower side (22) of the touch piston has a bigger diameter.
9. Device according to claim 1, characterized in that the fixing means (46) comprises a pressure spring (47) with external thread arranged in a recess (45) of the main plate (6), wherein the fixing means (46) penetrates the main plate (6) and via the pressure spring (47) is adjustable a weight compensation of the touch table (7) and/or the upper part of the tool (50).
10. Device according to claim 1, characterized in that in a seat (51) of the main plate (6) is positioned the sensor (52), the measuring point (MP) of which is adjustable.
11. Device according to claim 1, characterized in that the main plate (6) is fixed by screwing means at a facing the ram frontal wall of the main cylinder (3).
12. Device according to claim 1, characterized in that the main plate (6) is torsion-proof and axially movable arranged by parallel to the stroke axis HU guided in holes (38) guiding pins (40).
13. Device according to claim 1, characterized in that in the main cylinder (3) the V-shaped projection pins (11) and the V-shaped projection pressure plate (12) are coaxially arranged with regard to the stroke axis (HU) and that in the main plate (6) is provided a central support (14) in alignment with the stroke axis (HU), wherein the pressure plate (12) is hold by a retaining ring (13) at the touch table (7).
14. Method for preventing a tool consisting of an upper and an lower part from breaking during fine blanking and/or forming in a press with a device according to claim 1, wherein the guided in the main cylinder of the fine blanking head V-shaped projection piston and touch piston for producing a V-shaped projection force and a stripping force are admitted to an adjustable pressure from a hydraulic system, wherein the single pressure values for the pistons are adjusted by valves triggered by a computer, characterized by diverting the pressure force by means of a non-positive and/or positive connection by hydraulic locking and unlocking of a touch table (7), a main plate (6), a central support (14), a main cylinder (3) and an adjusting nut (4) into the head piece (2) of the press and by axially shifting of V-shaped projection piston (9) and touch piston (10) in alignment with the stroke axis (HU) prior to feeding in the pressure force until the non-positive and/or positive connection between V-shaped projection pressure plate (12), V-shaped projection pins (11), touch piston (10) and V-shaped projection piston (9) is reached, wherein between touch piston and V-shaped projection pins with hydraulic means is adjusted a gap distance (SP) and between main plate and touch table with mechanical means is adjusted an adjusted to the gap distance (SP) weight compensated detection distance (TA), the change of which is scanned by the V-shaped pressure plate (12) and/or the touch table (7) and detected by a sensor (52) transmitting a signal to the computer (52) for causing the immediate stop of the press.
15. Method according to claim 14 characterized by the following steps:

a Preloading of V-shaped projection piston and touch piston to a preloading pressure (P12) to realize the non-positive connection between them b Permanently applying a different from the preloading pressure (P1) differential pressure (P3) to the touch piston for axially shifting the touch piston, c Maintaining a detection distance (TA) adjusted to a gap distance between touch piston and V-shaped projection pins by the applied to the touch piston differential pressure (P3) and the acting against it preloading pressure (P1) for realizing a non-positive connection between touch piston and V-shaped projection piston, wherein the preloading pressure (P1), the touch piston pressure (P2) and the differential pressure (P3) are adjusted to the condition P1 >> P3 and P2 = 0, d Superseding the hydraulic fluid being under differential pressure (P3) in the allocated to the touch piston pressure room by the applied to the upper pressure room preloading pressure (Pl), e Relieving the V-shaped projection piston by switching off the preloading pressure (P1) in the upper dead point for reaching a motionless state of V-shaped projection piston and touch piston, f Stripping of V-shaped projection piston and touch piston by applying a stripping pressure (P4) and a touch piston pressure (P2) with a constant value to the pressure rooms of V-shaped projection piston and touch piston, g Shifting the V-shaped projection piston and the touch piston until a sensor triggers a signal, h Switching off the stripping pressure (P4) for the V-shaped projection piston and the touch piston and applying the preloading pressure (P1) to the upper pressure room of the V-shaped projection piston, i Repeating the step sequence a) to h) in case the sensor has not detected a depending on the ram stroke premature change of the detection distance (TA).
16. Method according to claims 14 and 15, characterized in that the preloading pressure (P1) is adjusted to a high pressure of more than 110 bar.
17. Method according to claims 14 and 15, characterized in that the touch piston pressure (P2) and the stripping pressure (P4) are adjusted to a low pressure below 110 bar and the differential pressure (P3) is adjusted to a low pressure below 110 bar or to zero.
18. Method according to claims 14 and 15, characterized in that the touch piston pressure (P2) and the differential pressure (P3) can be switched on and switched off.
CA2705646A 2009-06-03 2010-05-27 Device and method for preventing a tool from breaking during fine blanking and/or forming a work piece Active CA2705646C (en)

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EP20090007353 EP2258496B1 (en) 2009-06-03 2009-06-03 Device and method for preventing a tool from breaking during fine cutting and/or reforming a work piece
EP09007353.7 2009-06-03

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EP (1) EP2258496B1 (en)
JP (1) JP5634134B2 (en)
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US11292047B2 (en) 2019-05-03 2022-04-05 Ford Global Technologies Mechanical die pressure monitoring system
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CN112378770A (en) * 2020-11-20 2021-02-19 三门县远景建筑材料有限公司 Compression testing machine with positioning structure for concrete building material
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Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH454577A (en) * 1966-03-08 1968-04-15 Osterwalder Ag punch
CH490963A (en) 1968-05-02 1970-05-31 Hydrel Ag Tool safety device on a press
JPS4937228B1 (en) * 1969-09-10 1974-10-07
GB1308641A (en) * 1970-01-27 1973-02-21 Shoreham Precision Tools Ltd Presses
JPS4889073U (en) * 1972-01-28 1973-10-26
DE2419390C2 (en) 1974-04-23 1983-09-29 SMG Süddeutsche Maschinenbau-Gesellschaft mbH, 6833 Waghäusel Tool break protection
US5285722A (en) * 1992-11-16 1994-02-15 The Minster Machine Company Press shutheight adjustment using hydraulic tie rod assemblies
US5349902A (en) * 1993-04-20 1994-09-27 The Minster Machine Company Press shutheight adjustment mechanism
US6267050B1 (en) * 1998-11-25 2001-07-31 The Minster Machine Company Quick access/adjustment piston
FR2811602B1 (en) 2000-07-13 2002-10-11 Montabert Ets HYDRAULIC PERCUSSION APPARATUS
KR100400385B1 (en) 2001-07-11 2003-10-08 주식회사 코막 Control valve for hidraulic breaker
KR100772735B1 (en) 2003-05-06 2007-11-01 이일재 Hydraulic percussion device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104752262A (en) * 2013-12-31 2015-07-01 北京北方微电子基地设备工艺研究中心有限责任公司 Cover plate detection device and detection method, reaction chamber and semiconductor processing equipment
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CN107716700A (en) * 2017-11-13 2018-02-23 东莞市兆丰精密仪器有限公司 A kind of fully automatic high-speed perforating press

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ATE542617T1 (en) 2012-02-15
JP2010280001A (en) 2010-12-16
KR20100130566A (en) 2010-12-13
JP5634134B2 (en) 2014-12-03
KR101691230B1 (en) 2016-12-29
CA2705646C (en) 2017-02-14
CN101954433A (en) 2011-01-26
US20100319553A1 (en) 2010-12-23
EP2258496A1 (en) 2010-12-08
EP2258496B1 (en) 2012-01-25

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